A remote shifting system for a marine propulsion unit that employs only forward, neutral and reverse sensing switches for the transmission. A control routine is established whereby when a shift is initiated, the transmission is first moved to its neutral position and then moved to the desired shift position if it is other than a neutral condition. A warning circuit is incorporated for providing a warning and/or protective action in the event a shift does not occur within a predetermined normal time period.

This invention relates to a remote shifting system for a marine propulsion unit and more particularly to an improved and simplified electronically controlled remote shift mechanism for a marine outboard drive.
As is well known, most marine propulsion units include a forward neutral reverse transmission which permits the watercraft to be operated in either forward or reverse drive mode or in a neutral condition. Frequently, it is desirable to provide a remote actuator for actuating the transmission, which is generally positioned with the outboard drive portion of the propulsion unit and frequently in its lower unit. One type of remote control mechanism which has been employed incorporates an electric follow-up system wherein the operator controls a remote shift lever which, in turn, transmits a position signal to a remote servo motor for actuating the transmission control to the selected position. Such systems normally employ a potentiometer on the transmission shift lever and on the shift control with a comparator circuit to determine discrepancies in the two positions so as to operate a motor to bring coincidence into the two positions. Although such arrangements are satisfactory, the use of two potentiometers can give rise to expense in the control mechanism.
In order to reduce the cost of the system, it would be desirable to employ only position responsive switches at the transmission control end. However, when only position responsive switches are employed it is impossible for the system to determine when the transmission control is in an intermediate position between its forward, neutral and reverse positions.
It is, therefore, a principal object of this invention to provide an improved remote shifting system for a marine propulsion unit which permits the use of position responsive switches in the control mechanism.
It is a further object of this invention to provide a control routine for a remote shifting system for a marine propulsion unit that permits the use of only position responsive switches in the transmission control.

Remote shifting system for marine propulsion unit


A varistor has a ceramic composition to exhibit nonlinear voltage-current characteristics, and at least two electrodes arranged to sandwich at least a portion of the ceramic composition. The ceramic composition contains a mixture phase in which a first phase containing zinc oxide as a major component, and a second phase comprised of an oxide of Ca and Si are mixed.

1. Field of the Invention
The present invention relates to a varistor.
2. Related Background Art
A known varistor is one having a ceramic composition to exhibit nonlinear voltage-current characteristics, and at least two electrodes arranged to sandwich at least a portion of the ceramic composition (e.g., cf. Japanese Patent Application Laid-open No. 2002-246207).


An assembly of a plurality of lens holders includes a housing formed with a cavity for slidably receiving the lens holders in alignment with each other. One lens holder is formed with a bore of a first diameter having internal threads at a smaller diameter portion thereof. The other lens holder is formed with a bore having internal threads of a diameter equal to that of the smaller diameter of the first lens holder. The outer face of the housing is formed with a bore in alignment with the bores of the two lens holders and has a diameter at least as large as that of the first diameter to permit an adjusting implement formed with external threads to be inserted via the aligned bores in the housing and the two lens holders to precisely adjust the two lens holders with respect to each other.

The present invention relates to assemblies of linearly arranged elements which are to be precisely adjusted with respect to each other. The invention is particularly useful in a lens assembly, and is therefore described below with respect to this application.
Many types of assemblies, and particularly lens assemblies, include a plurality of linearly-arranged elements which must be precisely positioned with respect to each other. The conventional way of accomplishing this is to provide a separate adjusting screw or the like for each element, but this usually requires the assembly to have a separate access location for each of the individual adjusting means. In some types of assemblies, particularly lens assemblies, this may not be possible or convenient.

Assembly of precisely adjustable linearly-arranged elements, particularly lenses


An optical fiber canister (40) comprises a tapered cylindrical bobbin (42) having a length of optical fiber (28) wound thereon to form a fiber pack (43). The optical fiber (28) is wound so as to pay out with a preselected circumferential payout direction component (45), as well as a longitudinal payout direction component. The canister (40) has an optical fiber payout opening (50) through which the optical fiber (28) is paid out. An air duct (60, 62, 90) from the exterior of the canister (40) to the interior of the canister (40) has an air outlet (70) within the interior of the canister (40) oriented to direct the air flow oppositely to the preselected circumferential payout direction (45). The optical fiber canister (40) may be mounted within a missile (20), and the air duct (90) desirably extends from the exterior of the missile (20) to the interior of the canister (40), to provide a velocity-dependent air flow that damps out the helical motion of the optical fiber (28) during payout, permitting the optical fiber (28) to be paid out smoothly even though the payout opening (50) is small.

This invention relates to optical fibers, and, more particularly, to a canister system for dispensing optical fibers linearly.
Optical fibers are strands of glass fiber processed so that light transmitted therethrough is subject to total internal reflection. A large fraction of the incident intensity of light directed into the optical fiber is received at the other end of the optical fiber, even though the optical fiber may be hundreds or thousands of meters long. Optical fibers have shown great promise in communications applications, because a high density of information may be carried along the optical fiber and because the quality of the signal is less subject to external interferences of various types than are electrical signals carried on metallic wires. Moreover, the glass fibers are light in weight and made from a highly plentiful substance, silicon dioxide.
Glass optical fibers are typically fabricated by preparing a preform of glasses of two different optical indices of refraction, one inside the other, and processing the preform to a fiber. The optical fiber is coated with a polymer layer termed a buffer to protect the glass from scratching or other damage. As an example of the dimensions, in a typical configuration the diameter of the glass optical fiber is about 125 micrometers, and the diameter of the optical fiber plus the polymer buffer is about 250 micrometers (approximately 0.010 inch).
For such very fine optical fibers, the handling of the optical fiber to avoid damage that might reduce its mechanical strength and/or light transmission properties becomes an important consideration. In one approach, the optical fibers are wound in a winding direction onto a cylindrical or tapered cylindrical bobbin (collectively termed herein a "tapered" bobbin even though the angle of the taper may be zero) with many turns adjacent to each other in a side-by-side fashion. After one layer is complete, another layer of optical fiber is laid on top of the first layer, and so on. A weak adhesive is typically applied to the layers of optical fiber, to hold them in place. The final assembly of the bobbin and the wound layers of optical fiber is termed a canister, and the mass of wound optical fiber is termed the fiber pack. When the optical fiber is later to be used, the fiber is paid out from the canister in a direction generally parallel to the axis of the cylinder.
As the optical fiber is paid out from the canister, it naturally follows a helical pattern because the optical fiber continuously unwinds from the bobbin. In some instances, the helical component to the payout of the optical fiber can be undesirable. For example, if the optical fiber is to be dispensed through a tube or opening in the canister wall of small diameter located a few centimeters from the bobbin, the helical motion can cause the optical fiber to rub against the entry of the tube, with possible damage to the optical fiber. In another example, the helical pattern can produce an increased radar signature, which is undesirable if the optical fiber is being dispensed from a missile in flight.
There is therefore a need for a technique to damp out the helical motion of the optical fiber as it is dispensed from the bobbin in a direction generally parallel to the axis of the bobbin. The approach must be compatible with other aspects of the storage and use of the optical fiber, such as long storage life in a variety of conditions. Also, the damping would desirably vary according to the rate of dispensing, so that more damping is available for increased dispensing rates. The present invention fulfills this need, and further provides related advantages.

Air damped linear optical fiber dispenser


The present invention includes vehicle seat having monitor movable from a storage state to a use state, in the storage state the monitor is positioned in a backboard of a seatback and the monitor faces the backboard, in the use state a display surface of the monitor is exposed outside of the backboard facing a rear of the vehicle, wherein the backboard is semitransparent.

1. Field of the Invention
The present invention relates to a vehicle seat assembled with a monitor that can be stored in a backboard.
2. Description of the Related Art
A vehicle has been proposed having a monitor by which pictures of DVD, TV programs or the like can be appreciated. To allow such pictures to be directly appreciated even from a rear seat, a vehicle seat has been proposed, which has a monitor on a back of a seat at the front of the vehicle such as a driver seat or passenger seat. In this case, an exposed condition of the monitor, in which the monitor is continuously projected from a seat, is not preferable in the light aesthetics, an outlook of the front from a rear seat, and safety. Thus, JP-A-2004-352239 shows a seat, in which a monitor is stored in a recess formed on a back of a seatback in a freely rising and setting manner. In that seat, when the monitor is not used, it is covered by an opaque cap, and the monitor is folded into the back of the seatback and stored therein. When the monitor is used, the cap is opened so that the monitor is projected in a rising manner. JP-A-9-142186 shows a technique for displaying an operation picture on a monitor operating each sitting positions in a seat.
In the vehicle seat of JP-A-2004-352239, pictures on the monitor cannot be seen unless the opaque cap is opened. In particular, even if not only pictures, but also time, temperature indication, a sitting position in a seat and the like are desired to be continuously displayed on the monitor, such information cannot be confirmed unless the cap is put to a horizontal position.
Thus, there is a need in the art for a vehicle seat in which displayed information on a monitor can be viewed not only in a condition where the monitor is exposed to the outside of a seatback, but also in a condition where the monitor is stored in the seatback.


A “candy bar” form factor wireless handset (200) having an internal antenna (222, 306) a bottom end of an main internal circuit board (208) and an auxiliary field shaping conductor (226, 502, 1102, 1304) at a top end of the main internal circuit board (208) behind the an earpiece speaker (104). The field shaping conductor (226, 502, 1102, 1304) is spaced from a ground plane 304) of the main circuit board (208) but is inductively and capacitively coupled to the ground plane (304). The field shaping conductor (226, 502, 1102, 1304) lowers the electric field intensity in front of the earpiece speaker and thereby reduces interference of the wireless handset (200) with hearing aids.

Wireless handsets (cellular telephones) can generate interference with hearing aids that leads to audible noise. The Federal Communication Commission (FCC) will soon require that at least some of the wireless handsets offered by each wireless service provider meet certain standards aimed at reducing interference with hearing aids. These Hearing Aid Compatibility (HAC) standards stipulate that the electric and magnetic field strength within at least six squares of a nine square measurement grid centered on the speaker of a qualifying handset and spaced from the handset by 1 centimeter be below predetermined limits. FIG. 1 depicts a "candy bar" form factor wireless handset 100 with the aforementioned nine square measurement grid 102.
It has been found that it is particularly difficult to make "candy bar" wireless handsets that meet the FCC HAC requirements. Most currently available "candy bar" wireless handsets use internal antennas that are located either the bottom or top end of the handsets internal printed circuit board. Examples of internal antennas include the Planar Inverted "F" (PIFA) antenna and the more advanced Folded Inverted Conformal Antenna (FICA). Generally, internal antennas of wireless handsets use the ground plane of the wireless handset's internal circuit board and/or other conductive parts of the handset as a counterpoise in at least some operating bands (e.g., operating bands in the 800 MHz to 900 MHz range). Consequently, high electric field regions occur both near the antenna and at the opposite end of the handset (at the remote end of the counterpoise.) Such high electric fields are problematic for meeting the FCC HAC requirements.
Thus, what is needed is way to control the pattern of electric fields near the earpiece speaker of wireless handsets so that interference with hearing aids will be reduced and the FCC HAC requirements will be met.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.

Wireless handset with improved hearing aid compatibility


An image display device has pixels each of which includes sub-pixels of four or more colors, and displays a high-definition image that has been subjected to sub-pixel-level filtering processing. The image display device includes a display panel in which color filters of sub-pixel colors including three principal colors of red, green, and blue as well as at least one color other than the three principal colors are arranged regularly; and an image processor that performs filtering processing with respect to an input image signal. The image processor includes: a principal color conversion section that generates sub-pixel signals corresponding to the sub-pixel colors, respectively, from the input image signals Rin, Bin, and Gin of the three principal colors; and a sub-pixel enhancement section that gives, to the sub-pixel signals, position information in accordance with an order of arrangement of the color filters of the sub-pixel colors in the display panel, and performs the filtering processing sub-pixel by sub-pixel.

Conventionally, image display devices having pixels each of which is composed of three sub-pixels for displaying three primary colors of red (R), green (G), and blue (B) so as to perform color display have been spread widely. Besides, it has been known widely that in an image display device, the following filtering processing of various types are carried out: contour enhancement processing performed by superposing high-frequency components extracted with use of a high-pass filter; and smoothing processing performed by removing high-frequency components with use of a low-pass filter. For example, by performing the contour enhancement processing, a sharp image with higher definition can be obtained. Alternatively, by performing the smoothing processing, noises are removed, whereby a smoother image can be obtained.
Still further, in order to achieve further higher definition, a technique for generating a display image by performing the following steps has been proposed: generating an image with sub-pixel-level fineness by interpolation, generating an enhanced image in which components belonging to a specific frequency band of the sub-pixel-level image are enhanced, and performing sub-pixel rendering processing (see, for example, JP2005-141209A).

Image display device and image display method


Aspects of the present disclosure describe systems, methods, and structures including integrated laser systems that employ external chirping structures that may advantageously include phase shifters and/or one or more filters. Further aspects of the present disclosure describe systems, methods, and structures including laser systems that employ external chirping structures that may advantageously include optical phased arrays.

As is known, laser systems and light generated therefrom have found widespread applicability in an innumerable number of contemporary application areas including medicine, communications, transportation, and navigation—among others. Of importance to these applications, the laser light oftentimes must be spectrally broadened and exhibit an altered output frequency as a function of time ("chirped"). Accordingly, systems, methods, and structures that facilitate the production and/or control of such chirped laser light would represent a welcome addition to the art.

Laser frequency chirping structures, methods, and applications


There is provided a method, apparatus and integrated circuit for measuring a signal, the apparatus comprising a plurality of sample stages arranged in series, each sample stage comprising a delay element, and a sample element, wherein an input of the sample element is coupled to an output of the delay element, and a strobe line for controlling a sample time of the sample elements, the strobe line comprising a plurality of strobe delay elements arranged in series, wherein an output of each strobe delay element is coupled to one or more sample elements.

Modern integrated circuits contain many high frequency, high accuracy analog elements such as phase lock loops, LVDS, DDR PHY/IO, etc. It can be difficult to accurately measure such signals during testing and characterization of new integrated circuits, or chips. This can make debugging of circuits difficult and requires the use of expensive test equipment, along with expenditure of significant resources and time.
In some cases test equipment operating externally to the integrated circuit requires complicated synchronization to enable reading of the signals to be tested within a very small measurement window. This is complicated the difficulty in allowing internal signals of the integrated circuit to be read externally to the chip, for example to allow triggering of a measurement based on a different signal. Thus, it is necessary to trigger measurements based on some external timing which may not be accurately synchronized to the event that it is desired to measure.
Furthermore, while the value of a signal at a specified point in time can be measured by the test equipment, it is not possible to measure a time when a switching event occurs. Rather, multiple measurements must be taken, and the data searched for the desired event. Due to the time delays and latencies involved with the use of external test equipment, this makes it difficult to determine an exact time the event occurs, particularly in a modern circuit which may be operating an GHz frequencies.
Due to the above difficulties, characterization and testing of integrated circuit designs can currently require many man months of time to be spent by specialist engineers, which is expensive and may still not result in a fully accurate characterization of the circuit being tested.

On-die signal measurement circuit and method


A multiple virtual machine system with a microprocessor for executing instructions and issuing memory reads and writes to a current partition of a plurality of partitions. The multiple virtual machine may contain a partition management unit for receiving the memory reads and writes from the microprocessor for the current partition. A current partition cache is selected by the partition management unit for the current partition to receive the current partition memory reads and writes from the partition management unit. The current partition cache resolves memory read hits and misses. A next partition cache is selected by the partition management unit when the next partition becomes active on the microprocessor to receive next partition memory reads and writes from the microprocessor. An external memory containing data organized in frame blocks and containing cache block addresses for the plurality of partitions provides data to the microprocessor when the current partition cache resolves the memory miss, and provides appropriate frame block data to the next partition cache to restore the next partition cache to a previous state.

This invention relates to computers, microprocessors, and more specifically to a multiple virtual machine system employing partitioning with an efficient cache memory design.
Microprocessors are widely used in many embedded processor applications. The many different embedded applications require varying degrees of performance and cost. For example low-cost low-power processors are required for portable applications with the central processing unit and other components forming a system-on-a-chip. Commercial processors are available for these applications. Low-cost commercial processors are used in consumer products such as appliances, entertainment systems, automobiles, etc.
Military and commercial avionics and communications systems require microprocessors for embedded applications with much higher performance and reliability. Microprocessors are required with a verifiable hardware design and with features such as built-in-test and monitoring capabilities for mission critical systems. To meet the requirements of these mission critical systems, commercial processors need to be investigated and custom microprocessors need to be developed. Approaches are needed that provide system-on-chip solutions, support high reliability, and provide for function partitioning and reconfiguration.
Currently one computer system is used for each unique function in avionics and communications equipment such as autopilots, flight management systems, and displays. The avionics computer systems offer only limited inter-functional dependencies in that they exchange sensor and control data. This computer system architecture provides strong functional isolation needed for critical avionics systems. Avionics systems typically must be certified to meet reliability standards established by regulatory agencies such as the Federal Aviation Administration. System certification involves verifying that all system components work properly together.
In order to reduce hardware costs involved with commercial and custom high performance microprocessors, it may be beneficial to provide one computer system to perform many distinct functions in avionics, communications, and other equipment. Having one computer system may substantially reduce certification costs in avionics systems. System functions are certified once, independently, and to the level appropriate to their criticality while a composition of functions retains individual certification.
Many different functions can be performed on one computer system by using virtual machines. A virtual machine is a platform-independent instruction set that allows a user a portable programming environment. Multiple virtual machines can run on a single physical processor through sharing or partitioning of the physical processor operation. The multiple virtual machines perform as if they were separate physical machines operating on one processor. A well-known virtual machine is the JAVA virtual machine.
With one computer system the avionics functions are no longer physically isolated. Interaction of functions must be considered without the physical isolation. Partitioning of functions provides the necessary isolation for safety critical avionics applications such that each function is guaranteed not to be affected by the operation of any other function.
Partitioning and multiple virtual machines are processing technologies that have applications to many areas including avionics and communications products. Partitioning and multiple virtual machines can provide direct cost advantages in software development. Multiple levels of certified software can co-exist on the same processor. Software can be certified once and re-used in multiple application environments. These advantages are possible with brick-walled partitioning provided with partition management and with deterministic execution. Efficient techniques to provide deterministic behavior with on-chip cache have not been developed. What is needed is an approach to provide deterministic execution that does not significantly increase the required cache size and is independent of the number of partitions or virtual machines.
A multiple virtual machine computer system comprising an efficient cache design is disclosed. In one embodiment of the invention the multiple virtual machine computer system comprises a microprocessor that executes instructions for one of a plurality of partitions operating on the multiple virtual machine. The microprocessor issues memory reads and writes for a current partition to a partition management unit. The partition management unit selects a current partition cache for the current partition to receive the current partition memory reads and writes from the partition management unit and to resolve memory read hits and memory misses. The partition management unit selects a next partition cache when the next partition becomes active to receive next partition memory reads and writes from the microprocessor. An external memory contains data organized in frame blocks and contains cache block addresses for the plurality of partitions. The external memory provides data to the microprocessor when the current partition cache resolves the memory misses. The external memory provides appropriate frame block data to the next partition cache when the current partition cache is active by cycle stealing or using spare cycles from the current partition to restore the next partition cache to a previous state. The next partition cache may also be restored to a previous state during a gap of time while switching from the current partition to the next partition. Two or three cache memories may be employed in the present invention. The cache memory storing and restoring and multiple virtual machine context switching may also be performed in software.
It is an object of the present invention to provide efficient support of high performance and deterministic behavior in multiple virtual machine microprocessor architectures.
It is an object of the present invention to provide an efficient cache design that is adaptable to cached microprocessor architectures.
It is a feature of the present invention to provide high-speed operation and deterministic behavior in a multiple virtual machine system with the addition of only two or three caches.
It is a feature of the present invention to be able to load caches using three different approaches.
It is an advantage of the present invention to be able to provide high-speed operation and deterministic behavior for multiple virtual machine applications in safety-critical avionics applications to reduce software certification costs.

Multiple virtual machine system with efficient cache memory design


A thermal shielding brick is useable for lining a combustion chamber wall. The thermal shielding brick has a hot side, which can be exposed to a hot medium a wall side located opposite the hot side, and a peripheral side that is joined to the hot side and to the wall side. A damping element is placed on the peripheral side and effectively prevents fragments from detaching from the thermal shielding brick if broken. A combustion chamber having an inner combustion chamber lining, includes the thermal shielding bricks. Further, a gas turbine, includes the combustion chamber.

Combustion spaces, such as, for example, a furnace, a hot-gas duct or a combustion chamber of a gas turbine, are known in which a hot medium is produced and/or directed. A thermally and/or thermomechanically highly loaded combustion space is provided with an appropriate lining in order to protect it from excessive thermal stressing. The lining of the combustion space is normally made of heat-resistant material and protects a wall of the combustion space from direct contact with the hot medium, for example a hot combustion gas, and from the associated high thermal loading. In addition, the combustion gases may have oxidative and/or corrosive constituents, which may have a lasting adverse effect on the combustion chamber wall if acted upon directly. There is therefore considerable interest in developing and improving the lining of a combustion space.
U.S. Pat. No. 4,840,131 discloses a fastening of ceramic lining elements to a wall of a furnace. In this case, a rail system which is fastened to the wall and has a plurality of ceramic rail elements is provided. The lining elements can be retained on the wall by the rail system. Further ceramic layers may be provided between a lining element and the wall of the furnace, inter alia a layer of loose, partly compressed ceramic fibers, this layer having at least the same thickness as the ceramic lining elements or a greater thickness. The lining elements in this case have a rectangular geometry with a planar surface. The lining elements are made of a heat-insulating refractory ceramic fiber material.
The application of a refractory lining to a wall of a furnace is likewise treated in U.S. Pat. No. 4,835,831. The refractory lining in this case is arranged in particular on a vertical wall. A layer consisting of glass fibers, ceramic fibers or mineral fibers is applied to the metallic wall of the furnace. This layer is fastened to the wall by metallic clamps or by adhesive. A wire mesh net having honeycomb meshes is applied to this layer. The mesh net likewise serves to protect the layer of ceramic fibers from falling down. By means of a suitable spraying process, a uniform closed surface of refractory material is applied to the layer fastened in this way. The method described largely avoids a situation in which refractory particles striking during the spraying are thrown back, as would be the case with direct spraying of the refractory particles onto the metallic wall.
Another type of lining of a thermally highly loaded combustion space is specified in EP 0 419 487 B1. The lining consists of thermal shielding elements which are mechanically retained on a metallic wall of the combustion space. The thermal shielding elements touch the metallic wall directly. In order to avoid excessive heating of the wall, e.g. as a result of direct heat transfer from the thermal shielding element or by ingress of hot medium into the gaps formed by the thermal shielding elements which adjoin one another, cooling air, the "sealing air", is admitted to the space formed by the wall of the combustion space and the thermal shielding element. The sealing air prevents the penetration of hot medium up to the wall and at the same time cools the wall and the thermal shielding element.
EP 0 724 116 A2 discloses a ceramic lining for walls of thermally highly stressed combustion spaces, for example of gas-turbine combustion chambers. The lining consists of wall elements made of high-temperature-resistant structural ceramic, e.g. silicon carbide (SiC) or silicon nitride (Si3N4). The wall elements are elastically fastened to a metallic supporting structure (wall) of the combustion chamber in a mechanical manner by means of a central fastening bolt. A thick thermal insulating layer is provided between the wall element and the wall of the combustion space, so that the wall element is at an appropriate distance from the wall of the combustion chamber. The insulating layer, which in relation to the wall element is about three times as thick, is made of refractory ceramic material which is prefabricated in bricks. The dimensions and the external shape of the wall elements can be adapted to the geometry of the space to be lined.
A wall segment for a combustion space and a combustion space of a gas turbine are described in WO 99/47874. Specified in this case is a wall segment for a combustion space, to which a hot fluid can be admitted, having a metallic supporting structure and a thermal protection element fastened to the metallic supporting structure. Inserted between the metallic supporting structure and the thermal shielding element is a deformable separating layer, which is intended to absorb and compensate for possible relative movements of the thermal shielding element and the supporting structure. Such relative movements may be caused, for example, in the combustion chamber of a gas turbine, in particular an annular combustion chamber, by different thermal expansion behavior of the materials used or by pulsations in the combustion chamber, which may arise during irregular combustion for producing the hot working medium or due to resonance effects. At the same time, the separating layer causes the relatively inelastic thermal protection element to rest in a more planar manner overall on the separating layer and the metallic supporting structure, since the thermal protection element penetrates at least partly into the separating elements. The separating layer is thus also able to compensate for production-related unevenness on the supporting structure and/or the thermal protection element, which unevenness may lead locally to an unfavorable concentrated introduction of force.

Thermal shielding brick for lining a combustion chamber wall, combustion chamber and a gas turbine


A nuclear reactor having a core catcher comprising a group of upright assemblies disposed side-by-side beneath the reactor core. The assemblies each comprise a stack of spaced sacrificial plates mounted on a graphite column which collectively support the core. The plates are profiled to form vertical elongate cavities in which molten core debris can collect and solidify by heat conduction to the plates. The heat capacity of the core catcher is enhanced by cooling coils in the columns and by melting of the sacrificial plates which improves the heat conductivity of the debris.

This invention relates to nuclear reactors which are fuelled with ceramic fuel, that is, nuclear fuel comprising one or more compounds such as an oxide or carbide of a fissile metal or metals (and of a fertile metal for breeding where applicable). The invention has particular reference to expedients known in the art as `core catchers`, which serve to catch and disperse the fuel constituting the reactor core as a safeguard against operation under extreme and emergency conditions such that a melt down of the fuel occurs. A typical example of fuel for which such a core catcher would be provided is mixed plutonium/uranium oxides such as is used in a gas cooled fast reactor.
The problems associated with the core catchers include dispersing the molten fuel debris to avoid criticality and in addition removing as much heat as possible from the dispersed melt, firstly, to avoid boiling of the fuel melt which would release fission products and plutonium aerosols, and secondly to bring about solidification of the molten debris to prevent its penetrating the reactor containing vessel. Ceramic nuclear fuels are notoriously poor heat conductors which exacerbates the problem. Therefore dispersion into as many small volumes as possible is desirable. Yet another problem resides in the avoidance of premature solidification of molten fuel in the upper region of the core catcher. If such a condition should occur upward radiation of heat from the melt could cuase serious damage to the remaining reactor components and thermal insulation therefore it is an object of the invention to provide a ceramic fuelled nuclear reactor having a core catcher which, in addition to dispersing a fuel melt into numerous small valumes, also reduces the tendency for premature solidification of fuel melt in the upper regions.


The subject disclosure is directed towards an object (e.g., an aspected vector, queue, map, stack and so forth) container having an exclusive interface, a shared-read-only interface and a shared-write (and read) interface to a common set of data. Use cases during runtime determine the appropriate interface to use. No locking is needed with methods of the exclusive interface or the read-only interface. The shared-write interface is configured to have only concurrency safe methods. Also described is blocking the use of other interfaces while one interface is in use, and the use of reference counter tracking to know when no concurrent readers and/or writers remain, to allow transitioning to use a different interface.

When data structures such as containers are intended to be used in a concurrent/multi-threaded environment, a performance/productivity problem arises. More particularly, to achieve thread-safety, many concurrent versions of objects, containers, and other data structures offer a non-restricted interface that has poor performance due to coarse synchronization. The current alternative, the mixed interface, offers a single interface with a mix of fine grain synchronized and unsynchronized methods with slightly better performance, but this corresponds to a productivity problem since the user is required to provide synchronization for many of the unsynchronized (unsafe) methods. Moreover, although this alternative has slightly better performance, it still provides reduced performance relative to the serial and read-only equivalents. The alternative also results in reduced developer productivity due to the difficulty of the user having to ensure and provide synchronization of the unsynchronized (unsafe) methods.
As a result, developers are forced to make a tradeoff between either the mixed interface with reduced productivity (and somewhat reduced performance) alternative, or significantly reduced performance in the exclusive, coarsely-synchronized alternative.

Aspected interfaces and methods for synchronized containers and other data structures


A float body for river fishing and trolling has a longitudinal fin projecting downwardly from the bottom of the float to cut through water being fished to locate the float in desired lateral locations relative to the riverbank or direction of trolling. A spring-loaded locking swivel arm is used to set the desired angle at which the fin cuts through the water. The line exit location is through the fin and approximately at the center of the float body rearwardly from the swivel arm for horizontal stability. The float includes line locking apparatus using ring members secured under spring pressure or by a threaded tightening nut.

Conventional fishing corks and floats are commonly used to keep afloat live bait and artificial lures while fishing in both moving and standing water. When using these devices in flowing streams or rivers, oftentimes it is necessary to fish from a bridge or a boat to effectively cover certain areas of the river. When used for trolling, conventional floats are pulled toward the wake of the boat where fish are easily spooked. Planer boards and outriggers are used to spread the lines away from the boat's wake. However, these set-ups are cumbersome and require substantial tackle and are generally limited to use with larger power boats.


An imaging optical lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element with refractive power has both an object-side surface and an image-side surface being aspheric. The fourth lens element with refractive power has both an object-side surface and an image-side surface being aspheric. The fifth lens element with refractive power has both an object-side surface and an image-side surface being aspheric. The sixth lens element with refractive power has both an object-side surface and an image-side surface being aspheric.

Technical Field
The present disclosure relates to an imaging optical lens assembly and an imaging apparatus. More particularly, the present disclosure relates to a compact imaging optical lens assembly and an imaging apparatus which is applicable to electronic devices.
Description of Related Art
In recent years, with the popularity of mobile terminals having camera functionalities, the demand of miniaturized optical systems has been increasing. The sensor of a conventional optical system is typically a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor. As the advanced semiconductor manufacturing technologies have allowed the pixel size of sensors to be reduced and compact optical systems have gradually evolved toward the field of higher megapixels, there is an increasing demand for compact optical systems featuring better image quality.
Conventional constructions of telephoto optical systems are mainly equipped with multiple spherical glass lens elements. The lens size of these systems becomes too large to carry, and the costs of manufacturing these systems become too high. Hence, the conventional optical systems cannot satisfy these photographic requirements of convenience and multi-functions.

Imaging optical lens assembly, imaging apparatus and electronic device


An electrical connector includes a housing, a conductive pin, a first seal, and a sealant. The housing has a bore and first and second ends exposed at different pressures when in use. The bore extends between the first and second ends. The conductive pin is arranged within the bore and configured to engage a first wire at the first end and a second wire at the second end. The first seal is arranged around the conductive pin and engaged between the conductive pin and the bore to provide seal therebetween. The sealant is provided to fill the bore between the first end and the first seal. The sealant may be an epoxy-based sealant.

Hydraulic control systems are used in many industrial and mobile applications, such as excavating equipment, hoists, lifting arms, and a number of similar devices. Such control systems typically include control valves in the form of a spool slidable within a bore, the position of the spool determining which of a pair of outlet ports is connected to relatively high pressure fluid and which is connected to a low pressure at any given time.
Often times, the hydraulic control systems contain electric devices arranged at different pressures. For example, some electric devices are arranged at atmospheric pressure, and other devices are arranged to be exposed to hydraulic fluid at a higher pressure than the atmospheric pressure. Typically, the electric devices arranged at different pressures are electrically connected through electrical connectors. Thus, such electrical connectors need to be reliably secured within the hydraulic control system and environmentally sealed between the different pressures.

High pressure sealed electrical connector


Provided is an actuator device including a piezoelectric element formed of a lower electrode, a piezoelectric layer, and an upper electrode, and displaceably provided on a substrate with a zirconium oxide layer interposed therebetween, the substrate having a silicon oxide layer formed by thermal oxidation on at least a surface, and an intermediate layer made of at least one material selected from the group consisting of titanium oxide, hafnium oxide, aluminum oxide, calcium oxide, and rare earth oxide, and provided between the silicon oxide layer and the zirconium oxide layer.

1. Technical Field
The present invention relates to an actuator device including a piezoelectric element formed of a lower electrode, a piezoelectric layer, and an upper electrode, and displaceably provided on a substrate with a zirconium oxide layer interposed therebetween, the substrate having a silicon oxide layer formed by thermal oxidation on at least a surface thereof, a method of manufacturing the same, and a liquid-jet head including the actuator device as a liquid-jet unit.
2. Related Art
As a piezoelectric element used in an actuator device, there is an element formed by sandwiching a piezoelectric layer made of a piezoelectric material exhibiting an electromechanical conversion function, for example, a crystallized dielectric material, between two electrodes of a lower electrode and an upper electrode. Such an actuator device is generally called a flexure-vibration-mode actuator device and is mounted on and used in a liquid-jet head, for example. Here, a typical example of the liquid-jet head includes an ink-jet recording head, for example, in which a part of a pressure generating chamber communicated with a nozzle orifice for ejecting ink droplets is formed of a vibration plate, and ink droplets are ejected from the nozzle orifice by displacing this vibration plate with a piezoelectric element so as to pressurize the ink in the pressure generating chamber. Meanwhile, as the actuator device to be mounted on the ink-jet recording head, for example, there is a device in which a piezoelectric material layer is formed over the entire surface of the vibration plate by a film-forming technique and this piezoelectric material layer is cut into shapes each corresponding to the pressure generating chamber by a lithography method to form piezoelectric elements provided independent from one another for the respective pressure generating chambers.
As such a piezoelectric element, there is an element formed of a lower electrode, a piezoelectric layer, and an upper electrode, and displaceably provided on a substrate with a zirconium oxide layer interposed therebetween, the substrate having a silicon oxide layer formed by thermal oxidation on a surface thereof (as disclosed in JP-A-2003-110158, JP-A-2005-166719, and JP-A-2005-295786, for example).
Formation of the silicon oxide layer on the surface of the substrate by thermal oxidation prevents pin holes and the like as compared to the case of forming the silicon oxide layer by use of a vapor deposition method such as a CVD method. Moreover, this leads to the formation of a layer formed on the silicon oxide layer which has no pin holes, the layer not being affected by the pin holes, thus eventually obtaining a desired actuator device. Meanwhile, in the liquid-jet head, passages such as the pressure generating chambers are formed by wet-etching the substrate. Here, a silicon oxide layer which has no pin holes is also needed in order to cause the silicon oxide layer to function as an etching stop layer at the time of the wet etching. Accordingly, the silicon oxide layer without pin holes has been obtained by forming the silicon oxide layer by thermal oxidation. Meanwhile, a component constituting the piezoelectric layer is diffused from the piezoelectric layer toward the silicon oxide layer at the time of baking at a high temperature a "precursor film" which is a state of the piezoelectric layer before crystallization. Here, the component diffused from the piezoelectric layer is prevented by the zirconium oxide layer.
However, when the zirconium oxide layer is formed on the silicon oxide layer formed by the above-described thermal oxidation, although there is no effect by the pin holes as very few pin holes exist on the silicon oxide layer, there has been a problem that the zirconium oxide layer having a uniform thickness cannot be formed because part of crystals constituting the zirconium oxide layer have grown abnormally due to a different reason from the effects by the pin holes, whose detailed cause of generation is unknown. As a result, there has been a problem that an actuator device having a desired displacement characteristic cannot be obtained since concave-convex portions formed on the zirconium oxide layer are transmitted to the lower electrode, the piezoelectric layer, and the upper electrode formed on the zirconium oxide layer, and thereby negatively affecting the state of film formation thereof.

Actuator device, method of manufacturing the same and liquid-jet head


A control device for an internal combustion engine performs feedback control so that the air-fuel ratio of the exhaust gas flowing into an exhaust purification catalyst becomes a target air-fuel ratio and switches the target air-fuel ratio to lean when an output air-fuel ratio of a downstream side air-fuel ratio sensor is judged rich and switches the target air-fuel ratio to rich when an output air-fuel ratio of the downstream side air-fuel ratio sensor is judged lean. The control device judges that the downstream side air-fuel ratio sensor has not become abnormal when the value of the excess/deficiency parameter from when switching the target air-fuel ratio to lean or rich to when the output air-fuel ratio of the downstream side air-fuel ratio sensor is judged rich or lean is larger than a predetermined limit value.

Known in the art is an exhaust purification system of an internal combustion engine provided with an exhaust purification catalyst arranged in an exhaust passage of the internal combustion engine and able to store oxygen and an air-fuel ratio sensor or oxygen sensor arranged at an upstream side and downstream side in this exhaust purification system in a direction of flow of exhaust (for example, PTLs 1 to 4). In such an exhaust purification system of an internal combustion engine, an air-fuel ratio detected by the upstream side air-fuel ratio sensor (below, referred to as an "output air-fuel ratio") is controlled to a target air-fuel ratio by feedback control of the amount of feed of fuel from a fuel injector.
Among these, in the exhaust purification system described in PTL 1, the output air-fuel ratio of the downstream side air-fuel ratio sensor is used as the basis for control of the target air-fuel ratio. Specifically, if the output air-fuel ratio of the downstream side air-fuel ratio sensor becomes a rich judged air-fuel ratio richer than the stoichiometric air-fuel ratio or becomes less, the target air-fuel ratio is switched to a lean air-fuel ratio leaner than the stoichiometric air-fuel ratio. In addition, if the output air-fuel ratio of the downstream side air-fuel ratio sensor becomes a lean judged air-fuel ratio leaner than the stoichiometric air-fuel ratio or becomes more, the target air-fuel ratio is switched to a rich air-fuel ratio richer than the stoichiometric air-fuel ratio. According to PTL 1, due to this, it is considered possible to suppress the outflow of unburned fuel or NOx etc. from the exhaust purification catalyst. In addition, by making the oxygen storage amount of the exhaust purification catalyst vary between a maximum storable oxygen amount (maximum amount of oxygen which the exhaust purification catalyst can store) and zero, the oxygen storage ability of the exhaust purification catalyst can be maintained high.

Control device for an exhaust purification system of an internal combustion engine


In a method for end processing a surface of a shaft-like workpiece, the following steps are performed in the following series, and the workpiece rotates about an axis of rotation:

The present invention relates to a method for end processing of a surface of a shaft-like workpiece.
The operating characteristics, in particular of camshafts, and the ability to distribute a lubricant on the surface of the camshaft depend critically on the surface structure. One measurement of the surface structure is roughness. In this connection, it is desirable that the surface, in particular one of the bearing points of the camshaft, have individual, deep grooves, whereby the region between the grooves is as "smooth" as possible. In order to characterize the roughness profile of a surface determined with known methods, it is known to transfer a roughness profile determined on a measuring length to an Abbott Curve, whereby in case of a S-shaped course of the Abbott Curve, parameters can be determined from the Abbott Curve, such as core roughness depth Rk, reduced peak height Rpk, and reduced valley depth Rvk. In the frame of this nomenclature, it already is possible that a relatively small reduced peak height Rpk is achieved with a relatively greatly reduced valley depth Rvk, which, in turn, lies in the range of the core roughness depth Rk. For achieving such a surface, it is known to machine the surface first with a relatively coarse tool and subsequently, to polish with a relatively fine-grained tool.
The problem associated with the known methods is that greatly enhanced reduced valley depth Rvk relative to the core roughness depth Rk by producing deeper grooves cannot be achieved in any reproducible manner.

Method for producing grooves on a camshaft

Abstract: a) finishing the surface with a first finishing tool,

Abstract: b) machining the surface with a scoring tool, whereby the scoring tool produces at least one groove running in a circumferential direction, whereby the at least one groove produces 3 to 12 profiled gorges on a reference segment which reference segment has a length that is predetermined by a measuring method for roughness determination and which is extending on the surface parallel to the axis of rotation, each of said profiled gorges having a depth and width, whereby the ratio of the depth and width of each profiled gorge is greater than 2 and a distance between adjacent profiled gorges is substantially the same,c) machining the surface with the first finishing tool or a second finishing tool.


Crash sensor arrangement for determining whether a crash involving the vehicle requires deployment of an occupant restraint device including a first electronic crash sensor mounted in the crush zone of the vehicle for measuring a reaction of the crush zone to a crash and outputting a signal representative of the measurements and a processor coupled to the first sensor for processing the signal to determine whether the restraint device should be deployed. The first sensor may include an accelerometer, a gyroscope or an elongate member arranged to sense the reaction of the crush zone over a substantial part of the front, side or rear of the vehicle. Optionally, a second electronic crash sensor is mounted outside the crush zone to measure a reaction of the vehicle other than crush of the crush zone. Both sensors input signals to the processor which is programmed to determine whether the restraint device should be deployed using an algorithm and data from the first and/or second sensors. The second sensor may be mounted in association with the passenger compartment.

Pattern recognition techniques, such as artificial neural networks are finding increased application in solving a variety of problems such as optical character recognition, face recognition, voice recognition, and military target identification. In the automotive industry in particular, pattern recognition techniques have now been applied to identify various objects within the passenger compartment of the vehicle, such as a rear facing child seat, as well as to identify threatening objects with respect to the vehicle, such as an approaching vehicle about to impact the side of the vehicle. See, for example, U.S. Pat. Nos. 5,829,782, 6,343,810 and RE 37,260 which are entirely incorporated herein by reference.
Pattern recognition techniques have also been applied to sense automobile crashes for the purpose of determining whether or not to deploy an airbag or other passive restraint, or to tighten the seatbelts, cutoff the fuel system, or unlock the doors after the crash (see, for example, U.S. Pat. No. 5,684,701 which is entirely incorporated herein by reference). In the past, pattern recognition techniques were not applied to forecast the severity of automobile crashes for the purpose of controlling the flow of gas into or out of an airbag to tailor the airbag inflation characteristics or to control seatbelt retractors, pretensioners or energy dissipaters to the crash severity. Furthermore, such techniques were also not to control the flow of gas into or out of an airbag to tailor the airbag inflation characteristics to the size, position or relative velocity of the occupant or other factors such as seatbelt usage, seat and seat back positions, headrest position, vehicle velocity, etc.
Electronic crash sensors currently used in sensing frontal impacts typically include accelerometers mounted in the passenger compartment that detect and measure the vehicle accelerations during the crash. The accelerometer produces an analog signal proportional to the acceleration experienced by the accelerometer and hence the vehicle on which it is mounted. An analog to digital converter (ADC) transforms this analog signal into a digital time series. Crash sensor designers study this digital acceleration data and derive therefrom computer algorithms which determine whether the acceleration data from a particular crash event warrants deployment of the airbag. This is usually a trial and error process wherein the engineer or crash sensor designer observes data from crashes where the airbag is desired and when it is not needed, and other events where the airbag is not needed. Finally, the engineer or crash sensor designer settles on the "rules" for controlling deployment of the airbag which are programmed into an algorithm which seem to satisfy the requirements of the crash library, i.e., the crash data accumulated from numerous crashes and other events. The resulting algorithm is not universal and most such engineers or crash sensor designers will answer in the negative when asked whether their algorithm will work for all vehicles. Such an algorithm also merely determines that the airbag should or should not be triggered. Heretofore, no attempt has been made to ascertain or forecast the eventual severity of the crash or, more specifically, the velocity change versus time of the passenger compartment during the crash from the acceleration data obtained from the accelerometer.
Several papers as listed below have been published pointing out some of the problems and limitations of electronic crash sensors that are mounted out of the crush zone of the vehicle, usually in a protected location in the passenger compartment of the vehicle. These sensors are frequently called single point crash sensors. Technical papers which discuss the limitations of current single point sensors along with discussions of the theory of crash sensing, which are relevant to this invention and which are incorporated entirely herein by reference, are listed below.
These papers demonstrate, among other things, that there is no known theory that allows an engineer to develop an algorithm for sensing crashes and selectively deploying the airbag except when the sensor is located in the crush zone of the vehicle. These papers show that, in general, there is insufficient information within the acceleration signal measured in the passenger compartment to sense all crashes. Another conclusion suggested by these technical papers is that if an algorithm can be found which works for one vehicle, it will also work for all vehicles since it is possible to create any crash pulse measured in one vehicle, in any vehicle. Note in particular SAE paper 920124 referenced below.
In spite of the problems associated with finding the optimum crash sensor algorithm, many vehicles on the road today have electronic single point crash sensors. Some of the problems associated with single point sensors have the result that an out-of-position occupant who is sufficiently close to the airbag at the time of deployment will be injured or killed by the deployment itself. Fortunately, systems are now being developed which monitor the location of occupants within the vehicle and can suppress deployment of the airbag if the occupant is more likely to be injured by the deployment than by the accident. These systems do not, however, currently provide the information necessary for the control of airbag systems, or the combination of seatbelt and airbag systems, which have the capability of varying the flow of gas into or out of the airbag and thus to tailor the airbag to the size and weight of the occupant (or possibly another morphological characteristic of the occupant), as well as to the position, velocity and seatbelt use of the occupant. More particularly, no such system existed, prior to the conception by the current assignee's employees, which uses pattern recognition techniques to match the airbag deployment or gas discharge from the airbag to the severity of the crash or the size, weight, position, velocity and seatbelt use of an occupant.
Since there is insufficient information in the acceleration data, as measured in the passenger compartment, to sense all crashes and since some of the failure modes of published single point sensor algorithms can be easily demonstrated using the techniques of crash and velocity scaling described in the above-referenced technical papers, and moreover since the process by which engineers develop algorithms is based on trial and error, pattern recognition techniques such as neural network should be able to be used to create an algorithm based on training the system on a large number of crash and non-crash events which, although not perfect, will be superior to all others. This in fact has proved to be true and is the subject the invention disclosed in U.S. Pat. No. 5,684,701 referenced above. That invention is based on the ability of neural networks to forecast, based on the first part of the crash pulse, that the crash will be of a severity which requires that an airbag be deployed.
As will be discussed in greater detail below, an improvement on that invention, which is the subject of the instant invention, carries this process further by using a neural network pattern recognition system to forecast the velocity change of the crash over time so that the inflation and/or deflation of the airbag, and the seatbelt, can be optimized. This invention further contemplates the addition of the pattern recognition occupant position and velocity determination means disclosed in U.S. Pat. Nos. 5,829,782, 6,343,810 and RE 37,260 also referenced above. Finally, the addition of the weight of the occupant is contemplated to provide a measure of the occupant's inertia or momentum as an input to the system. The combination of these systems in various forms can be called "smart airbags" or "smart restraints" which will be used as equivalents herein. In a preferred implementation, the crash severity is not explicitly forecasted but rather, the value of a control parameter used to control the flows of inflator gas into or out of the airbag is forecasted.
Smart airbags can take several forms which can be roughly categorized into four evolutionary stages, which will hereinafter be referred to as Phase 1 (2, 3 or 4) Smart Airbags, as follows:    1) Occupant sensors such as the disclosed in the U.S. patent applications cross-referenced above use various technologies to turn off the airbag where there is a rear facing child seat present or if either the driver or passenger is out-of-position to where he/she is more likely to be injured by the airbag than from the accident.    2) Occupant sensors will be used along with variable inflation or deflation rate airbags to adjust the inflation/deflation rate to match the occupant first as to his/her position and then to his/her morphology. The occupant sensors disclosed in the cross-referenced patent applications will also handle this with the possible addition of an occupant weighing system. One particular weight measuring system which makes use of strain gages mounted onto the seat supporting structure is disclosed in U.S. Pat. No. 5,748,473 and another that makes use of a fluid filled bladder is disclosed in U.S. Pat. No. 6,442,504 both of which are incorporated entirely herein by reference. At the end of this phase, little more can be done with occupant measurement or characterization systems.    3) The next improvement, and the subject of the instant invention, is to use a pattern recognition system such as neural networks as the basis of a crash sensor system not only to determine if the airbag should be deployed but also to predict the crash severity from the pattern of the initial portion of the crash pulse. Additionally, the crash pulse will continue to be monitored even after the decision has been made to deploy the airbag to see if the initial assumption of the crash type based on the pattern up to the deployment decision was correct. If the pattern changes indicating a different crash type, the flow rate to the airbag can be altered on the fly, i.e., substantially instantaneously. This crash sensor system can consist of a single electronic accelerometer based passenger compartment sensor, a multiple sensor system that also includes either electronic or mechanical crush zone mounted sensors and in the most sophisticated cases the passenger compartment sensor is replaced by an inertial measurement unit (IMU). Such an IMU can consist, of up to three accelerometers and up to three gyroscopes, usually based on MEMS technologies. It can also be coupled to the vehicle navigation system whereby the accuracy of the IMU can be enhanced through a technique such as a Kalman filter and a GPS or DGPS system.    4) Finally, anticipatory sensing using pattern recognition techniques such as neural networks will be used to identify the crash before it takes place and select the deployment characteristics of the airbag to match the anticipated crash with the occupant size and position. Such an anticipatory sensor is described in U.S. Pat. No. 6,343,810.
Any of these phases can be combined with various methods of controlling the pretensioning, retraction or energy dissipation characteristics of the seatbelt. Although the main focus of this invention is the control of the flows of gas into and out of the airbag, it is to be recognized that control of the seatbelt, or any other restraint, can also benefit from this invention and that the condition of the seatbelt can be valuable input information into the pattern recognition system.
When a crash commences, the vehicle starts decelerating and an accelerometer located in the passenger compartment, and/or one or more satellite or crush zone mounted accelerometers, begins sensing this deceleration and produces one or more electronic signals that vary over time in proportion to the magnitude of the deceleration. These signals contain information as to the type of the crash which can be used to identify the crash. A crash into a pole gives a different signal than a crash into a rigid barrier, for example, even during the early portion of the crash before the airbag triggering decision has been made. A neural network pattern recognition system can be trained to recognize and identify the crash type from the early signal from a passenger compartment mounted sensor, for example, and further to forecast ahead the velocity change versus time of the crash. Naturally, if the neural network also has information from satellite or crush zone mounted sensors, the accuracy of the forecast is significantly improved. Once this forecast is made, the severity and timing of the crash can be predicted. Thus, for a rigid barrier impact, an estimate of the eventual velocity change of the crash can be made and the amount of gas needed in the airbag to cushion an occupant as well as the time available to get that amount of gas into the airbag can be determined and used to control the airbag inflation.
Taking another example, that of a crash into a highway energy absorbing crash cushion. In this case, the neural-network-based sensor determines that this is a very slow crash and causes the airbag to inflate more slowly thereby reducing the incidence of collateral injuries such as broken arms and eye lacerations.
In both of these cases, the entire decision making process takes place before the airbag deployment is initiated. In another situation where a soft crash is preceded by a hard crash, such as might happen if a pole were in front of a barrier, the neutral network system would first identify the soft pole crash and begin slowly inflating the airbag. However, once the barrier impact began, the system would recognize that the crash type has changed and recalculate the amount and timing of the introduction of gas into the airbag and send appropriate commands to the inflation control system of the airbag to possibly vary the introduction of gas into the airbag. Again, if crush zone mounted sensors are present, the accuracy of the crash severity is greatly enhanced.
There are many ways of controlling the inflation of the airbag and several are now under development by the inflator companies. One way is to divide the airbag into different charges and to initiate these charges independently as a function of time to control the airbag inflation. An alternative is to always generate the maximum amount of gas but to control the amount going into the airbag, dumping the rest into the atmosphere. A third way is to put all of the gas into the airbag but control the outflow of the gas from the airbag through a variable vent valve. For the purposes herein, all controllable apparatus for varying the gas flow into or out of the airbag over time will be considered as a gas control module whether the decision is made at the time of initial airbag deployment, at one or more discrete times later or continuously during the crash event.
The use of pattern recognition techniques in crash sensors has another significant advantage in that it can share the same pattern recognition hardware and software with other systems in the vehicle. Pattern recognition techniques have proven to be effective in solving other problems related to airbag passive restraints. In particular, the identification of a rear-facing child seat located on the front passenger seat, so that the deployment of the airbag can be suppressed, has been demonstrated. Also, the use of pattern recognition techniques for the classification of vehicles about to impact the side of the subject vehicle for use in anticipatory side impact crash sensing shows great promise. Both of these pattern recognition systems, as well as others under development, can use the same computer system as the crash sensor and prediction system of this invention. Moreover, both of these systems will need to interact with, and should be part of, the diagnostic module used for frontal impacts. It would be desirable for cost and reliability considerations, therefore, for all such systems to use the same computer system or at least be located in the sane electronic module. This is particularly desirable since computers designed specially for solving pattern recognition problems, such as neural-computers, are now available and can be integrated into a custom application specific integrated circuit (ASIC).
In Society of Automotive Engineers (SAE) Paper No. 930650 entitled "A Complete Frontal Crash Sensor System, the authors conclude that airbag crash sensors mounted in the crush zone are necessary for the proper sensing of airbag-required frontal crashes. They also conclude that such sensors should sense crashes to all portions of the front of the vehicle and that sensors which sense the crush of the vehicle are preferred. The theory of crush sensing is presented in the above-referenced U.S. patents and patent applications and in reference 6 below.
The tape switch and rod-in-tube crush sensors described in the above-referenced U.S. patents and patent applications have performed successfully on various staged vehicle frontal crashes into barriers and poles. These sensors are generally not sufficient for sensing side impacts as discussed in reference 11 below, however, they can be successful when used in conjunction with a passenger compartment mounted electronic sensor or as a safing sensor. Similarly, they are also being considered when a deployable device, such as an airbag, is used for rear impacts. Newer elongate crush zone mounted sensors are being developed that continuously measure the relative displacement, velocity change or acceleration of a particular location in the crush zone and therefore can give much improved information about the locating of an impact and the characteristics of the crash such as its severity.
Three types of sensors have been widely used to sense and initiate deployment of an air bag passive restraint system. These sensors include an air damped ball-in-tube sensor such as disclosed in U.S. Pat. Nos. 3,974,350, 4,198,864, 4,284,863, 4,329,549 and 4,573,706 (all in the name of Breed), a spring mass sensor such as disclosed in U.S. Pat. Nos. 4,116,132 and 4,167,276 (both in the name of Bell) and a passenger compartment mounted electronic sensor such as is now part of several air bag systems. Each of these sensors has particular advantages and shortcomings that were discussed in detail in U.S. Pat. No. 4,995,639 referenced above.
The use of tape or ribbon switch technology as a crush switch was also disclosed in the '639 patent. Further research has shown that an improvement of this particular implementation of the invention has significant advantages over some of the other implementations since the switch can be easily made long and narrow and it can be made to respond to bending. In the first case, it can be designed to cover a significant distance across the vehicle that increases the probability that it will be struck by crushed material or bent as the crush zone propagates rearward in the vehicle during a crash. In the second case, it can be made small and located to sense the fact that one part of the vehicle has moved relative to some other part or that the structure on which the sensor is mounted has deformed.
Other crush zone mounted crash sensors including crush switch designs where the width and height dimensions are comparable, must either be large and thus heavy, expensive and difficult to mount, or there is a possibility that the randomly shaped crushed material which forms the boundary of the crush zone will bridge the sensor resulting in late triggering. This crushed material frequently contains holes, wrinkles or folds or portions that may even be displaced or torn out during the crash with the result that it is difficult to guarantee that a particular small area where the sensor is mounted will be struck early in the crash.
A significant improvement results, therefore, if the sensor can stretch across more of the vehicle or if it can determine that there has been relative motion or deformation of a portion of the vehicle on which the sensor is mounted. The improved sensors described herein are small in height and thickness but can extend to whatever length is necessary to achieve a high probability of a sensor triggering on time in a crash.
It has been found that conventional designs of tape or ribbon switches have the drawback that the force required to close the switch is very small compared with the forces which are normally present in automobile crashes. During routine maintenance of the vehicle, the normal tape switch may be damaged or otherwise made to close and remain closed, with the result that later, when the vehicle encounters a pot hole or other shock sufficient to cause the arming sensor to close, an inadvertent air bag deployment can result. Similarly, if the tape switch is mounted on the front of the radiator support, which is a preferred mounting locating for crush zone sensors, hail, heavy rain, stones or other debris from the road might impact the tape switch and cause a momentary closure or damage it. If this happens when the vehicle experiences a shock sufficient to cause the arming sensor to close, an inadvertent air bag deployment might also occur. The force typically required to close a tape switch is less than one pound whereas tens of thousands of pounds are required to stop a vehicle in a crash and local forces greatly in excess of 20 pounds are available to actuate a sensor during a crash.
The present invention seeks to eliminate these drawbacks through the use of a tape switch, rod-in-tube or coaxial cable design that requires either a large force to actuate or a bending of the device due to structural deformation as explained below.
In 1992, the assignee of the current invention published reverence 5 where the authors demonstrate that there is insufficient information in the non-crush zone of the vehicle to permit a decision to be made to deploy an airbag in time for many crashes. The crash sensors described herein and in the patents and patent applications referenced above, provide an apparatus and method for determining that the crush zone of the automobile has undergone a particular velocity change. This information can be used by itself to make the airbag deployment decision. As airbag systems become more sophisticated, however, the fact that the vehicle has undergone a velocity change in the crush zone can be used in conjunction with an electronic sensor mounted in the passenger compartment to not only determine that the airbag should be deployed but an assessment of the severity of the crash can be made. In this case, the front crush zone mounted sensor of the type disclosed herein can be used as an input to an electronic algorithm and thereby permit a deployment strategy based on the estimated severity of the accident. Although the sensors described herein are one preferred approach of providing this capability, the sensors disclosed in the above referenced patents would also be suitable. Alternately, in some cases, sensors of another design can fulfill this function. Such sensors might be based on the electromechanical technologies such as the ball-in-tube sensor described in U.S. Pat. No. 4,900,880 and now electronic sensors can be used as crush zone mounted sensors for this purpose as is the object of the instant invention.
Self-contained airbag systems contain all of the parts of the airbag system within a single package, in the case of mechanical implementations, and in the case of electrical or electronic systems, all parts except the primary source of electrical power and, in some cases, the diagnostic system. This includes the sensor, inflator and airbag. Potentially these systems have significant cost and reliability advantages over conventional systems where the sensor(s), diagnostic and backup power supply are mounted separate from the airbag module. In mechanical implementations in particular, all of the wiring, the diagnostic system and backup power supply are eliminated. In spite of these advantages, self-contained airbag systems have only achieved limited acceptance for frontal impacts and have so far not been considered for side impacts.
The "all-mechanical" self-contained systems were the first to appear on the market for frontal impacts but have not been widely adopted partially due to their sensitivity to accelerations in the vertical and lateral directions. These cross-axis accelerations have been shown to seriously degrade the performance of the most common all mechanical design that is disclosed in Thuen, U.S. Pat. No. 4,580,810. Both frontal and side impact crashes frequently have severe cross-axis accelerations.
Additionally, all-mechanical self contained airbag systems, such as disclosed in the Thuen patent, require that the sensor be placed inside of the inflator which increases the strength requirements of the inflator walls and thus increases the size and weight of the system. One solution to this problem appears in Breed, U.S. Pat. No. 4,711,466, but has not been implemented. This patent discloses a method of initiating an inflator through the use of a percussion primer in combination with a stab primer and the placement of the sensor outside of the inflator. One disadvantage of this system is that a hole must still be placed in the inflator wall to accommodate the percussion primer that has its own housing. This hole weakens the wall of the inflator and also provides a potential path for gas to escape.
Another disadvantage in the Thuen system that makes it unusable for side impacts, is that the arming system is sealed from the environment by an O-ring. This sealing method may perform satisfactorily when the module is mounted in the protected passenger compartment but it would not be satisfactory for side impact cases where the module would be mounted in the vehicle door where it can be subjected to water, salt, dirt, and other harsh environments.
Self-contained electrical systems have also not been widely used. When airbags are used for both the driver and the passenger, self-contained airbag systems require a separate sensor and diagnostic for each module. In contrast to mechanical systems the electronic sensor and diagnostic systems used by most vehicle manufacturers are expensive. This duplication and associated cost required for electrical systems eliminates some of the advantages of the self contained system.
Sensors located in the passenger compartment of a vehicle can catch most airbag-required crashes for frontal impacts, particularly if the occupants are wearing seatbelts. However, researchers now believe that there are a significant number of crashes that cannot be sensed in time in the passenger compartment and that this will require the addition of another sensor mounted in the crush zone (see, for example, reference 5 below). If true, this will eventually eliminate the use of self-contained airbag systems for frontal impacts.
Some of these problems do not apply to side impacts mainly because side impact sensors must trigger in a very few milliseconds when there is no significant signal at any point in the vehicle except where the car is crushing or at locations rigidly attached to this crush zone. Each airbag system must be mounted in the crush zone and generally will have its own sensor. Self contained airbag systems have heretofore not been used for occupant protection for side impacts which is largely due to the misconception that side impact sensing requires the use of elongated switches as is discussed in detail in U.S. Pat. No. 5,231,253, incorporated by reference herein. These elongated prior art side impact crush-sensing switches are not readily adaptable to the more compact self-contained designs. The realization that a moving mass sensor was the proper method for sensing side impacts has now led to the development of the side impact self contained airbag system of this invention. The theory of sensing side impacts is included in the '253 patent referenced above.
In electro-mechanical and electronic self-contained modules, the backup power supply and diagnostic system are frequently mounted apart from the airbag system. If a wire is severed during a crash but before the airbag deploys, the system may lose its power and fail to deploy. This is more likely to happen in a side impact where the wires must travel inside of the door. For this reason, mechanical self-contained systems have a significant reliability advantage over conventional electrical systems.
Finally, the space available for the mounting of airbag systems in the doors of vehicles is frequently severely limited making it desirable that the airbag module be as small as possible. Conventional gas generators use sodium azide as the gas generating propellant. This requires that the gas be cooled and extensively filtered to remove the sodium oxide, a toxic product of combustion. This is because the gas in exhausted into the passenger compartment where it can burn an occupant and is inhaled. If the gas is not permitted to enter the passenger compartment, the temperature of the gas can be higher and the products of combustion can contain toxic chemicals, such as carbon dioxide.
These and other problems associated with self-contained airbag systems and side impact sensors are solved by the invention disclosed herein.
Every automobile driver fears that his or her vehicle will breakdown at some unfortunate time, e.g., when he or she is traveling at night, during rush hour, or on a long trip away from home. To help alleviate that fear, certain luxury automobile manufacturers provide roadside service in the event of a breakdown. Nevertheless, unless the vehicle is equipped with OnStar or an equivalent service, the vehicle driver must still be able to get to a telephone to call for service. It is also a fact that many people purchase a new automobile out of fear of a breakdown with their current vehicle. This invention is also concerned with preventing breakdowns and with minimizing maintenance costs by predicting component failure that would lead to such a breakdown before it occurs.
When a vehicle component begins to fail, the repair cost is frequently minimal if the impending failure of the component is caught early, but increases as the repair is delayed. Sometimes if a component in need of repair is not caught in a timely manner, the component, and particularly the impending failure thereof, can cause other components of the vehicle to deteriorate. One example is where the water pump fails gradually until the vehicle overheats and blows a head gasket. It is desirable, therefore, to determine that a vehicle component is about to fail as early as possible so as to minimize the probability of a breakdown and the resulting repair costs.
There are various gages on an automobile which alert the driver to various vehicle problems. For example, if the oil pressure drops below some predetermined level, the driver is warned to stop his vehicle immediately. Similarly, if the coolant temperature exceeds some predetermined value, the driver is also warned to take immediate corrective action. In these cases, the warning often comes too late as most vehicle gages alert the driver after he or she can conveniently solve the problem. Thus, what is needed is a component failure warning system that alerts the driver to the impending failure of a component sufficiently in advance of the time when the problem gets to a catastrophic point.
Some astute drivers can sense changes in the performance of their vehicle and correctly diagnose that a problem with a component is about to occur. Other drivers can sense that their vehicle is performing differently but they don't know why or when a component will fail or how serious that failure will be, or possibly even what specific component is the cause of the difference in performance. The invention disclosed herein will, in most cases, solve this problem by predicting component failures in time to permit maintenance and thus prevent vehicle breakdowns.
Presently, automobile sensors in use are based on specific predetermined or set levels, such as the coolant temperature or oil pressure, whereby an increase above the set level or a decrease below the set level will activate the sensor, rather than being based on changes in this level over time. The rate at which coolant heats up, for example, can be an important clue that some component in the cooling system is about to fail. There are no systems currently on automobiles to monitor the numerous vehicle components over time and to compare component performance with normal performance. Nowhere in the vehicle is the vibration signal of a normally operating front wheel stored, for example, or for that matter, any normal signal from any other vehicle component. Additionally, there is no system currently existing on a vehicle to look for erratic behavior of a vehicle component and to warn the driver or the dealer that a component is misbehaving and is therefore likely to fail in the very near future.
Sometimes, when a component fails, a catastrophic accident results. In the Firestone tire case, for example, over 100 people were killed when a tire of a Ford Explorer blew out which caused the Ford Explorer to rollover. Similarly, other component failures can lead to loss of control of the vehicle and a subsequent accident. It is thus very important to accurately forecast that such an event will take place but furthermore, for those cases where the event takes place suddenly without warning, it is also important to diagnose the state of the entire vehicle, which in some cases can lead to automatic corrective action to prevent unstable vehicle motion or rollovers resulting in an accident. Finally, an accurate diagnostic system for the entire vehicle can determine much more accurately the severity of an automobile crash once it has begun by knowing where the accident is taking place on the vehicle (e.g., the part of or location on the vehicle which is being impacted by an object) and what is colliding with the vehicle based on a knowledge of the force deflection characteristics of the vehicle at that location. Therefore, in addition to a component diagnostic, the teachings of this invention also provide a diagnostic system for the entire vehicle prior to and during accidents. In particular, this invention is concerned with the simultaneous monitoring of multiple sensors on the vehicle so that the best possible determination of the state of the vehicle can be determined. Current crash sensors operate independently or at most one sensor may influence the threshold at which another sensor triggers a deployable restraint. In the teachings of this invention, two or more sensors, frequently accelerometers, are monitored simultaneously and the combination of the outputs of these multiple sensors are combined continuously in making the crash severity analysis.
For the purposes herein, the crush zone is defined as that part of the vehicle which crushes or deforms during a particular crash. This is a different definition from that used elsewhere and in particular in the above referenced technical papers. Also for the purposes herein, the terminology Crush Sensing Zone, or CSZ, will be used to designate that portion of the vehicle which is deformed or crushed during a crash at the sensor required trigger time. The sensor required trigger time is considered the latest time that a crash sensor can trigger for there to be sufficient time to deploy the airbag. This is determined by the airbag system designers and is a given parameter to the sensor designer for a particular crash. Naturally, there will be a different required sensor triggering time for each crash, however, it has been found, as reported in the above references, that the CSZ is remarkably constant for all crashes of the same type.
For example, the CSZ is nearly the same for all frontal barrier crashes regardless of the velocity of the crash. The same is true for 30 degree angle barrier crashes although the CSZ is different here than for frontal barrier crashes. Remarkably, and unexpectedly, it has also been found that when all frontal crashes at all different velocities are taken into account, the CSZ rearmost boundary becomes an approximate three dimensional surface lying mostly within the engine compartment of the vehicle, typically about ten to twelve inches behind the bumper at the center, and extending backward when crashes outside of the rails are considered. Finally, if a sensor is placed on this CSZ surface so that it is higher than the bumper level on the sides of the vehicle and lower in the vehicle center, as shown in FIG. 1 herein, it will do a remarkable job at discriminating between airbag required and non-deployment crashes and still trigger by the sensor required triggering time and before other sensors of comparable sensitivity. Naturally, this system is not perfect, however, it has been shown to do a better job than any other sensor system now in use.
It was this discovery which provided a basis for the subject matter described in U.S. Pat. No. 4,995,639 and then to the rod-in-tube sensor described in U.S. Pat. No. 5,441,301. During the process of implementing the rod-in-tube sensor, it was found that the same theory applies to rear impacts and that rod-in-tube sensors also have applicability to side impact sensing, although the theory is different.
In U.S. Pat. No. 5,694,320 (Breed), incorporated by reference herein, the theory of sensing rear impacts is presented and it is concluded that an anticipatory sensing system is preferred. This is because many people suffer whiplash injuries at rather low velocity impacts and if an inflatable restraint is used, the repair cost may be significant. To protect most people from whiplash injuries in rear impacts, therefore, a resetable system is preferred. The argument on the other side is that if the headrest is properly positioned, it will take care of all of the low velocity impacts and, therefore, an airbag can be used and reserved for the high velocity impacts where a crush sensing crash sensor would be used. The rod-in-tube sensor disclosed herein is, therefore, ideal for use with a deployable headrest mounted airbag for the same reasons that it is a good sensor for sensing frontal impacts. Since the rear of a vehicle typically has about one third of the stiffness of the vehicle front, electronic sensors will have even a tougher time discriminating between trigger and non-trigger cases for rear impacts. As disclosed in references 5 and 9 above, it is the soft crashes which are the most difficult for electronic sensors to sense in time.
Crush sensing crash sensors are not ideal for sensing side impacts alone, although the Volvo side impact system uses such a sensing system. This is because the sensing time is so short that there is virtually no crush (about two inches) at the time that the airbag must be deployed. Since there is very little signal out of the crush zone where electronic sensors are mounted, electronic sensors alone are not able to discriminate airbag required crashes from other crashes not requiring airbag deployment. The combination of the two sensors, on the other hand, can be used to provide a reliable determination. The crush sensor determines that there has been two inches of crush and the electronic sensor determines that the acceleration signal at that time is consistent with there being an airbag required crash. Thus, although they cannot be reliably used alone as a discriminating sensor for side impacts, the combined system does function properly. Recent advances now permit electronic crash sensors to be mounted in the side as well as the front and rear crush zones.
An alternate use of the crush sensor such as the rod-in-tube sensor in side impacts is as a safing sensor. In this role, it merely determines that a crash is in progress and the main discriminating function is handled by the velocity sensing sensors such as disclosed in U.S. Pat. No. 5,231,253 (assigned to the current assignee).
The rod-in-tube or coaxial cable crush velocity sensing crash sensors solve this side impact problem and thus applications include frontal, side and rear impacts, where in each case they enjoy significant advantages over all other crash sensing technologies.
The smart airbag problem is complex and difficult to solve by ordinary mathematical methods. Looking first at the influence of the crash pulse, the variation of crash pulses in the real world is vast and quite different from the typical crashes run by the automobile industry as reported in the below-referenced technical papers. It is one problem to predict that a crash is of a severity level to require the deployment of an airbag. It is quite a different problem to predict exactly what the velocity versus time function will be and then to adjust the airbag inflation/deflation control system to make sure that just the proper amount of gas is in the airbag at all times even without considering the influence of the occupant. To also simultaneously consider the influence of occupant size, weight, position and velocity renders this problem for all practical purposes unsolvable by conventional methods.
On the other hand, if a pattern recognition system such as a neural network is used and trained on a large variety of crash acceleration segments, as described in U.S. Pat. No. 5,684,701 referenced above, and a setting for the inflation/deflation control system is specified for each segment, then the problem can be solved. Furthermore, inputs from the occupant position and occupant weight sensors can also be included. The result will be a training set for the neural network involving many millions, and perhaps tens of millions, of data sets or vectors as every combination of occupancy characteristics and acceleration segment is considered. Fortunately, the occupancy data can be acquired independently and is currently being done for solving the out-of-position problem of Phase 1 smart airbags. The crash data is available in abundance and more can be created using the crash and velocity scaling techniques described in the above-referenced papers. The training using combinations of the two data sets, which must also take into account occupant motion which is not adequately represented in the occupancy data, can then be done by computer. Even the computer training process is significant to tax current PC capabilities and in some cases the use of a super-computer may be warranted.

Crash sensor arrangement for controlling deployment of an occupant restraint device

Automotive Technologies International, Inc.