Connection of a reference voltage to an inverter of an input buffer is controlled to protect the buffer from damage due to high voltage connected to the buffer so that the inverter is isolated from the reference voltage for application of the high voltage. A supply voltage may be connected to the inverter to ensure the output state of the buffer when the inverter is isolated from the reference voltage. In particular, an input buffer including an inverter having at least one p-channel and at least two n-channel transistors connected in series between a supply voltage and a reference voltage is protected from damage due to high voltage by floating the source and drain of n-channel transistors connected to receive input signals to be buffered. A control signal indicating a high voltage is connected to the buffer turns off the last n-channel transistor in the series chain of transistors and thereby removes the reference voltage from any remaining n-channel transistors in the chain. To ensure the state of the output of the buffer circuit while the n-channel transistors are thus isolated or floating, the drain of the first n-channel transistor in the series chain of transistors is clamped to the supply voltage. A p-channel transistor is connected between the drain of the first n-channel transistor in the chain and the supply voltage to provide the supply voltage clamp in response to the control signal.

The present invention relates in general to input buffers for semiconductor integrated circuits and, more particularly, to methods and apparatus for protecting input buffers from high voltages which are applied to integrated circuits for purposes such as testing and activating programmable interconnection elements. While the present invention can be utilized in a variety of fabrication techniques it will be described with reference to input buffers made using metal oxide silicon (MOS) fabrication techniques and, in particular, complementary MOS (CMOS) fabrication techniques for which it is particularly applicable and initially being applied.
Integrated circuits are tested to ensure that they are free of defects and that the circuits function properly and according to specifications. Testing includes "burn-in" where the circuits are subjected to extremes of operating temperatures and voltages to identify infant failures. Alternate testing can be performed on integrated circuits to test application specific features. Since alternate testing is normally performed by the manufacturer and is not intended to be used by purchasers of the integrated circuits, an electronic key is typically provided to enable the manufacturer to place the circuits into a test mode. A common key is a voltage which is a predetermined level above the maximum specified supply voltage for the circuits. Thus a high voltage key, sometimes referred to as a "supervoltage", may be applied to an input pin of an integrated circuit to place the circuit in a test mode. Once in the test mode, test vectors can be entered using other pins of the integrated circuit to perform required tests.
In some integrated circuits, defects can be corrected by means of one time programmable (OTP) permanent electrical connections which can be implemented with an antifuse. In dynamic random access memories (DRAMs), failing memory cells, rows or columns which are detected during testing can be remapped to functional redundant memory cells, rows or columns by selective permanent programming of antifuse elements. OTP connections are also used to permanently store data on integrated circuits such as programmable logic arrays (PALs), programmable logic devices and programmable read only memories (PROMs) and for other integrated circuit applications. An antifuse element is programmed by applying a programming voltage ranging from approximately 9 volts to approximately 13 volts which is above the maximum supply voltage for the integrated circuits.
In at least both these instances, testing using a supervoltage key and programming antifuses or similar devices, a high voltage is applied to an input pin of an integrated circuit. Portions of an integrated circuit which receive the supervoltage or the programming voltage are designed to withstand the high voltages at least for the time required to perform these operations. Unfortunately, these portions of the integrated circuits cannot be severed practically from input buffers of the integrated circuits which operate with normal signals levels and can be damaged by the high voltage applied for testing and programming. Even if the applied high voltage is less than the breakdown voltage of the devices making up the input buffer such that immediate damage is not done, the resulting voltage stress over time can result in permanent damage to the input buffer and failure of the integrated circuit.
Accordingly, there is a need for improved input buffers which are protected from damage due to high voltage inputs and methods of protecting input buffers.

High voltage protection for an integrated circuit input buffer


An image recording apparatus includes: a housing including a frame and a conveyance path; a recording device which records an image on a sheet conveyed along the conveyance path; a first roller located upstream of the recording device; a second roller opposed to the first roller; a guide member pivotable between a first position for partly defining the conveyance path and a second position where the conveyance path is open; a roller holder coupled to the guide member and supporting the second roller; an urging portion which urges the second roller toward the first roller; and an engaging portion supported by the roller holder and configured to, when the guide member is located at the first position, be engaged with the frame to position the roller holder to a third position where the second roller contacts the first roller by an urging force of the urging portion.

Technical Field
The present invention relates to an image recording apparatus configured to convey a sheet along a conveyance path and record an image on the sheet.
Description of the Related Art
There is known an image recording apparatus including a housing in which a conveyance path is defined, and an image is recorded on a sheet conveyed along the conveyance path. To perform maintenance and clear paper jam in the conveyance path, for example, the housing has an opening through which the conveyance path is accessible by a user. The opening can be opened and closed by a cover. Also, there is known a construction in which a nip of a conveying roller pair is released in conjunction with opening of the cover.


A row decoder for a nonvolatile memory having a low-voltage power supply that minimizes the load capacitance presented to a high voltage source without requiring additional circuitry. The row decoder accomplishes this by providing a local decoder having only one input requiring a boosted voltage higher than the power supply voltage. Further, predecoders are used to reduce the number of local decoders that receive the boosted voltage.

Nonvolatile semiconductor memory devices are well-known in the art. These devices include the erasable-programmable read-only memory (EPROM), the electrically-erasable-programmable read-only memory (EEPROM), and most recently, the flash memory. Flash memories are widely used for nonvolatile memory applications because they combine several of the most desirable characteristics of EPROMs and EEPROMs, including electrical erasability and erasability on a global or sector basis.
FIG. 1 is a block diagram of a flash memory 110. This block diagram is also representative of the architecture of other types of memories. The flash memory 110 includes a memory array 112, and address row decoder 114, a control circuit 116, an input/output (I/O) data circuit 118 and a column I/O circuitry 120. Memory 110 operates in response to external signals provided by a controlling device 122, such as a microprocessor.
The principle of operation of flash memories, such as memory 110, is well known and therefore is only briefly described herein. Controller 122 initiates a memory operation by asserting chip enables 101 and supplying address signals A.sub.0 -A.sub.N (corresponding to 2.sup.N+1 memory locations) designating the address of a memory location where the operation is to be performed. If the memory operation is a write or program operation, controller 122 supplies the data to be written to the addressed memory location via the bi-directional input/output lines I/O.sub.O -I/O.sub.K (corresponding to a K+1 bit wide memory word). If the memory operation is a read operation, the stored information from the addressed location is read out from the same bi-directional input/output lines I/O.sub.O -I/O.sub.K. Memory 110 also provides connections for external power supply (V.sub.cc) and ground (GND) signals.
The heart of memory 110 is memory array 112, which consists of flash memory cells, each capable of storing one bit of data, arranges in rows and columns. In the conventional manner, all of the cells in one row are energized for a memory operation (either a read or a program) by a word line WL uniquely associated with that row. A memory operation cannot be performed unless the word line associated with the target row of cells is activated.
The memory array 112 may be organized in sectors, each sector consisting of a plurality of rows of memory cells. During an erase operation, the memory cells in a selected sector are simultaneously erased.
At least a subset of the cells in a row (typically all of the cells that store data for one memory word) can be accessed simultaneously for a given memory operation via bit lines BL.sub.O -BL.sub.K. When the memory operation is a read, bit lines BL.sub.O -BL.sub.K are coupled to sense amplifiers in the column I/O 120 that "sense" the data stored in the corresponding cells of the row whose word line WL is enabled. When the memory operation is a program operation, the bit lines BL.sub.O -BL.sub.K carry the signals used to program the corresponding cells of the row associated with the enabled word line.
Control circuit 116 controls the other blocks of memory 110 when a chip enable signal 101 enables operation of the memory. Depending on the operation to be performed, the control circuit issues the appropriate control signals 117a and 117b to row decoder 114 and I/O data circuit 118, respectively.
Regardless of whether the memory operation is a read or program, row decoder 114 decodes the address signals A.sub.O -A.sub.N and activates the word line WL of the row that includes the memory word that is the target of the current memory operation. If the operation is a program, I/O data circuitry 118 buffers input data signals I/O.sub.O -I/O.sub.K and outputs the buffered data to column I/O 120 via bi-directional data bus 119. Column I/O 120 then latches the input signals in parallel onto the corresponding bit lines BL.sub.O -BL.sub.K. The signals on the bit lines BL.sub.O -BL.sub.K are used to program the cells composing the word whose word line was activated for the current operation by row decoder 114.
If the operation is a read, sense amplifiers in column I/O 120 sense the signals on the respective bit lines BL.sub.O -BL.sub.K, convert the sensed signals into binary (e.g., high or low) voltages that represent the programmed state of the addressed word and output the word's bit values to the I/O data circuit via bi-directional bus 119. The output data are buffered by I/O data circuit 118 and latched onto bi-directional data lines I/O.sub.O -I/O.sub.K for use by controller 122.
For proper operation of the memory cells in flash memory 110, row decoder 114 must provide the enabled word line WL with a voltage appropriate for the selected read, program or erase operation. For example, for conventional flash memory cells the enabled word line WL must typically reach a voltage of 4-5 volts (V) during a read operation to provide the memory cells with a sufficient read operation margin. The memory cells of some other types of nonvolatile memories, such as EPROMs, typically have similar word line voltage requirements.
Memory 110 may use a low-voltage power supply (V.sub.cc) of less than 4-5 V. Such low-voltage power supply memories, in which V.sub.cc may be as low as about 1.8 V, are increasing in popularity as battery-powered applications become more widespread. In these memories, a voltage higher than V.sub.cc is necessary to drive the word lines to the required 4-5 V.
One technique used to drive the word lines to the required higher-than-Vcc voltage couples a bootstrap circuit to one or more inputs of row decoder 114. The bootstrap circuit is a well-known circuit used to generate a signal having a peak voltage higher than V.sub.cc. The bootstrap circuit outputs a fixed amount of charge via a bootstrap capacitance C.sub.boot. The voltage produced at the output of the bootstrap circuit is highly dependent on the load presented by the row decoder, decoder load capacitance C.sub.D, to the bootstrap circuit. Decoder load capacitance C.sub.D primarily consists of the gate and parasitic capacitances of the transistors in row decoder 114 connected to the bootstrap circuit. If the decoder load capacitance C.sub.D is relatively large compared to the size of the bootstrap capacitance C.sub.boot, the bootstrap circuit may be unable to generate the voltage necessary to drive the word lines.
To compensate for a relatively large decoder load capacitance C.sub.D, the size of the bootstrap capacitance C.sub.boot may be increased. However, a large bootstrap capacitance is undesirable for several reasons. First, the large bootstrap capacitance increases the size of the bootstrap circuit. Second, it increases the amount of noise generated by the bootstrap circuit. Third, it increases the power consumed by the bootstrap circuit. Therefore, for a memory 110 having a low-voltage power supply, it is important for row decoder 114 to minimize the decoder load capacitance C.sub.D presented to the bootstrap circuit.
In view of the foregoing, it is an object of the present invention to provide a row decoder for a nonvolatile memory having a low-voltage power supply that minimizes the load capacitance presented to a high voltage source without requiring additional circuitry.

Row decoder for nonvolatile memory having a low-voltage power supply


A seal between an outer part and a circular cylindrical inner part, which is accommodated within the outer part at least in sections, includes a sealing ring having a groove portion and consisting of high-temperature-resistant thermoplastic plastics material. The outer part and the inner part are movable in a linear manner in relation to each other. A circumferential groove, into which the groove portion of the sealing ring is inserted at least in sections, is realized on an inner circumference of the outer part or on an outer circumference of the inner part. The sealing ring is in one part, and the groove is closed.

There are various approaches for seals of circular cylindrical sealing regions with sealing rings which are inserted into a circumferential groove of either a circular cylindrical inner part or of an outer part which is linearly movable in relation thereto.
In this case, closed and open grooves in which a sealing ring is accommodated in sections and in this way is fixed are known. The advantage of closed grooves is that expenditure on the production thereof is comparatively low and the disadvantage is that the sealing ring has to have a certain elasticity in order to be insertable into the groove. Sealing rings with less elasticity and higher temperature resistance can also be inserted into open grooves. A disadvantage of these types of seals is that expenditure on the production of the groove is higher as, once the sealing ring has been inserted, said groove has to be closed laterally by an additional part which is pushed on in the axial direction.
In addition, two-part sealing rings, which have a steel supporting ring into which a seal made of an elastomer is inserted, are also known for temperature-resistant seals. As a result of the low elasticity thereof, the supporting ring has to be inserted into an open groove which has to be closed laterally by a holding ring or locking ring.
In contrast, the object underlying the disclosure is to create a seal for parts which are moved in a linear manner, which provides a comparatively high temperature resistance with a low amount of expenditure on technical construction.
This object is achieved by a seal as described herein.


Several levels of a plurality (n) of design parameters of a product are inputted to means for designing trial products to output a trial product list based on a given orthogonal table (step 201). The products designed by the trial product designing are evaluated for a plurality (m) of evaluation items to afford evaluation data (step 203). A system range for each level is obtained from the evaluation data for the design parameter (step 204). The deducing means calculates an amount of information for each level from the system range and a design range for each level and adds the amounts of information for all of the evaluation items to find a total amount of information for each level (step 206). A characteristic curve for the design parameter is depicted based on the total amounts of information and a value of design parameter giving a minimum total amount of information is determined and employed as an optimum value of the design parameter (step 208). Optimum values of the other design parameters are similarly determined to afford optimum values for all of the design parameters (n). According to the method and system of the present invention, it is possible to efficiently an extremely easily determine optimum values of design parameters in a short period of time.

1. Field of the Invention
The present invention relates to a method for determining optimum values of design parameters, which makes it possible to determine optimum values of design parameters extremely easily and efficiently in a short time in product and system development.
2. Related Art
In product and system development in various industrial fields, a very important aspect of the development process is how to determine various kinds of design parameters such as materials, various dimensions including length, width, height, depth, thickness, diameter and pitch of products and components and parts constituting the products, and the relationships between components thereof including location, angle, distance and operation conditions. Therefore, a vast number of experiments are required to determine their optimum values, particularly, ina product required to meet several performance items, while it is also difficult to efficiently determine optimum values of a plurality of parameters even from the results of such experiments. Therefore, such determination must often rely on the experience and intuition of highly skilled persons.
On the other hand, methods have been suggested for obtaining optimum values by making a mathematical model containing given design parameters and required performance items (i.e., multivariate analysis). Practically, however, it is almost impossible to prepare such a mathematical model during development of products. In particular, when there are several required performance items and they should be determined systematically, preparation of such mathematical model itself requires a great number of experiments and, even if such a mathematical model can be prepared, it cannot always function well because of other factors including, for example, how relative importance is given to each required performance item, tradeoff among a plurality of the required performance items and the like.
A method utilizing the Taguchi method, which is used in the field of quality engineering, has also been known. However, this method can be used for only cases involving a single required performance item. Therefore, development of products by this method takes a lot of time and the result sometimes contradicts other items.
Therefore, an object of the present invention is to provide a method and system which make it possible to efficiently determine optimum values of design parameters using data from a small number of experiments. Another object of the present invention is to provide a method and system for easily determining the optimum values, which does not require experience of skilled artisans or the construction of a mathematical model for every design parameter.

Method of determining optimum product design parameters and system therefor


A method and apparatus for providing a stateless multiplatform instruction set architecture (ISA) for use in a computer system having a processor and memory storing a control program for implementing the invention. The system is used to statelessly execute instructions authored to correspond to a variety of different ISA""s on a unitary platform. The ISA of the invention uses a very long instruction word (VLIW) architecture with 64-bit instructions, of which several high-order bits are reserved for an ISA identifier tag. When the processor receives an instruction for execution, it inspects the instruction to determine from the ISA identifier tag to which original, native ISA the instruction corresponds. If the corresponding ISA is the native VLIW ISA for the processor, then the instruction is routed to the instruction dispatch unit of the processor, and thence to at least one functional unit for execution. If the corresponding ISA is not the native VLIW ISA, then the instruction is routed to one of a plurality of dynamic decode units (DDU""s), each DDU being controlled by a translation routine that translates the instructions from a non-native ISA to the native VLIW ISA. The translated instructions are then sent to the instruction dispatch unit, and on to the appropriate functional unit(s). Any instruction that includes unused bits, such as 64 bit instructions with free higher-order bits, can accommodate the ISA identifier tag by simply using the unused bits. Instructions that do not include unused bits, such as 32-bit instructions for non-VLIW architectures (e.g. the ISA""s for SPARC, PowerPC or x86), are appended with additional bits to bring the total to 64 bits, several of which are reserved for the ISA tag. The number of bits reserved for the ISA tag determines the number of non-native ISA""s that are recognized by the system; e.g., three bits allows for the native ISA plus seven non-native ISA""s to be recognized by the system. Incoming instructions corresponding to a non-native ISA for which no dynamic decode unit is available can be executed by conventional software emulation. Entire programs written for non-native ISA""s (using, e.g., 32-bit instructions) can be converted to the format for the native VLIW ISA by appending, at the instruction loading stage or in a separate process independent of execution, the additional bits necessary both to fill out the instruction word lengths and to include the ISA identifier tag bits.

This invention relates to a system, implemented in a computer processing unit, for executing instructions that comply with multiple, different instruction set architectures (ISA""s), and in particular to a processing unit that statelessly executes such instructions from different ISA""s.
A number of multiple-ISA platforms have been proposed which can accommodate different types of instructions by either binary translation or emulation. When binary translation is used, instructions that comply with a given instruction set architecture B (e.g. for x86 processors) can be executed on a second instruction set architecture A (e.g. in compliance with the ISA for SPARC/IEEE Standard 1754 processors) by first being binarily translated into instructions that ISA A understands. They are then executed just as if they were originally written for ISA A.
This approach entails considerable overhead, in that the entire program for ISA B must first be binarily translated before any of it can be run on the ISA-A processor. This not only involves a delay before the user can process the instructions, but ties up the processing of instructions, making the target processor unavailable until the binary translation is complete. Furthermore, the user may need only a small portion of the code being translated at a given time, making it highly inefficient to have to translate the entire code before accessing that portion.
In addition, binary translation involves the copying of the original instructions, which may or may not be allowable by the user""s license or by the law of the region where the user is executing the translation. Moreover, the translated instructions must be stored, so that the user is forced to save two copies of the code. If the translated copy is disposed of, then in order to use the code at a later time, it must again be translated to run on the ISA-A processor.
Another approach to executing code written for ISA B on a system using ISA A is emulation, which may be either software emulation or hardware emulation. Software emulation involves inputting instructions that the processor for ISA A would not normally recognize, converting them into equivalent ISA-A instructions, and executing the equivalent instructions in the A processor. This is done by setting the mode of the A processor to emulate ISA B, executing the ISA-B instructions, and then resetting the A processor back to mode A, i.e. for the native ISA.
The mode change is accomplished by a special program that instructs the processor (or the software emulation program) to interpret a succeeding block of data (until resetting of the mode) as ISA-B instructions, e.g. telling a SPARC processor that the forthcoming block of data actually comprises x86 instructions. The SPARC processor then interprets each data word, one by one, as an instruction. When the block of data has been so executed as instructions, the mode-setting program resets the processor mode to the its native (e.g. SPARC) mode.
While ISA-B instructions can successfully be executed this way, it is an inefficient and time-consuming approach, particularly for short sections of code where the overhead of mode changes becomes significant, and does not allow ISA-A and ISA-B instructions to be intermixed in a block of code; that is, the mode of the A processor must be reset every time code for a different ISA is encountered, which involves considerable cycle-time overhead. This is especially so when, during the execution of ISA-B code in processor A, an interrupt is received that requires the execution of a native ISA-A instruction. In this case, the ISA-A instruction must be trapped, interrupting the ISA-B code execution, and system checks whether it is in the correct mode; and since it is not, the mode must be reset to mode A. The trapped instruction is then executed, and the system then resets back to mode B to resume execution of the ISA-B code. This consumes an inordinate number of cycles.
Hardware emulation can run faster than software emulation, using one or more dynamic decode units (which may be an integral part of the native processor, or may be in an add-on module). Conventional hardware emulation, like software emulation, also uses a mode-setting program, so that the processor knows what type of ISA is to be emulated by a given set of instructions, and sends the instructions to the appropriate dynamic decode unit. Though there is a speed-up in execution, the overhead inefficiencies of mode resetting, trapping and interrupting are the same as for software emulation.
Another approach to accommodating multiple instruction set architectures involves incremental compilation, namely the compiling of portions of a program at a time. This has the advantage that an entire program needn""t be compiled when only a piece of it is needed, and in a given setting may save considerable compilation time. It has the distinct disadvantage that it does not efficiently handle self-modifying code, since whenever the code is modified it must be recompiled.
In a loop, where the same instructions are executed repeatedly, either software or hard: ware emulation leads to recompiling the same block of code many times over, since the emulation procedure interprets each command anew when it is encountered. Incremental compilation can lead to the same repetition of compiling, when code self-modification occurs. This repetition of compilation is extremely wasteful of processor cycles.
With the continued development of multiple instruction set architectures in the marketxe2x80x94such as the SPARC, x86 and PowerPC ISA""s and their respective operating systems (Solaris, DOS, MacOS)xe2x80x94it is becoming ever more important that users be capable of executing applications developed for these different instruction set architectures on a single hardware platform, in a manner that does not involve compilation of unneeded blocks of instructions, inefficient multiple compilation of instructions, or the overhead associated with mode setting. Particularly useful would be a system that not only efficiently accommodates multiple instruction set architectures, but can make use of the best of the many programs written for different ISA""s by allowing the intermixing of procedures with instructions from different instruction sets.
The present invention allows the execution of instructions designed for multiple, normally incompatible instruction set architectures in a single new unified architecture. Instructions for a given 32-bit architecture are coupled to an additional 32-bit word containing a predetermined block of bits constituting an ISA tag indicating the native ISA for the xe2x80x9cvisitingxe2x80x9d code, i.e. the 32-bit instruction set architecture for which the code was written. The entire 64-bit instruction stream is received by the xe2x80x9chomexe2x80x9d processor, which executes each instruction according to its ISA tag.
The home processor thus utilizes a 64-bit instruction set architecture, and in the foregoing manner can execute instructions from any 32-bit architecture, in real time without recompilation or software emulation. In addition to reducing overhead relative to previous methods, this allows for a programmer to freely make use of subroutines, software modules and objects from multiple ISA""s in a single application by simply tagging each imported block of code appropriately. The present invention is particularly suited to a VLIW (very long instruction word) architecture, by which a true stateless multi-ISA system is achieved.

Method and apparatus for multiplatform stateless instruction set architecture (ISA) using ISA tags on-the-fly instruction translation


Processes are disclosed for producing electronic interconnect devices, particularly semi-conductor wafers, with metal interconnect traces thereon wherein the surface of said device has improved planarity. Said planarity is achieved initially through the use of pulse reverse electrolytic plating techniques. Planarity is further enhanced by cathodically protecting the metal interconnect traces during the polishing operation. Cathodic protection is achieved by overtly applying a cathodic charge to said traces and/or by contacting said traces, during polishing, with a metal that is capable of sacrificial corrosion when in contact with the metal of the interconnect traces.

Copper interconnect devices are gaining rapid acceptance over aluminum interconnects, due to superior electrical conductivity of copper. Practicing what is known in the industry as damascene technology, one typically deals with interconnect trenches or vias that are filled with electroplated copper.
Ideally, copper electroplating would fill the trenches to be "level" with the patterned barrier layer underneath said copper "filling", or even more desirably, electroplated copper would fill said trenches only to the level of the surface of the dielectric. In actual industrial practice however, electroplated copper "overfills" and protrudes said trenches, resulting in a rough, "bumpy" surface topography, as opposed to one that is smooth or "planar". Thus, the pursuit of planarity has become a top priority in the fabrication of ULSI devices.
Chemical Mechanical Planarization (CMP) is currently the industry's premier choice to achieve planarization, as it serves to remove "excess", unwanted material that interferes with planarity.
CMP is perceived to be a complex process, involving both mechanical grinding or abrading, and also chemical etching/oxidation. The detailed, scientific mechanism of CMP is yet to be elucidated, especially as it relates to its chemical component. Hence, CMP still remains a very complex operation, relying principally on empirical, trial-and-error developments.
While great strides are being made to improve CMP processes (as reflected in the numerous patents which suggest approaches/solutions to given tasks), planarity problems associated with copper still remain perhaps the industry's greatest challenge, yet to be resolved satisfactorily.
The problem relating to planarity of copper conductors, is known in the trade as "dishing", which can be somewhat simplistically described as denoting the undesirable reduction of thickness of the metal line, causing an increase in electrical resistance and higher current density at a given voltage, than what the conductor has been designed for, resulting in functional deficiency of the interconnect device.
Even though the precise causes and mechanisms of dishing are poorly understood, as noted previously, there appears strong indication that dishing is caused both by mechanical gouging, scratching, overpolishing by the polishing media, as well as uncontrolled, indiscriminate chemical erosion of copper.
In embodying CMP processes and compositions, the prior art predominantly uses aqueous solutions or dispersions principally consisting of slurries of abrasive particles that comprise oxidizers, surfactants, viscosity modifiers, and the like. Abrasive particles are delivered to the wafer substrate via a porous polymer polishing pad, which polymer pad, embedded with the abrasive particles, is rotated against the wafer substrate to be planarized, where it removes unwanted, protruding matter. More recent developments disclose fixed abrasive pads that obviate the use of abrasive slurries, calling only for "cooling fluid" during CMP.
The inherent difficulty with above liquid systems, wherein water is essentially the principal, often sole, vehicle that carries the slurry to areas to be planarized, is that the distribution of abrasive particles in such aqueous, liquid media is non-uniform, resulting in uneven polishing, that aggravates dishing.
There is therefore a need in the industry for improved CMP compositions and methods that alleviate problems of planar non-uniformity, especially as they relate to dishing. There is also a need for an additional/alternate vehicle, other than aqueous suspensions that are prone to compositional non-uniformity, to deliver CMP ingredients/compositions to the wafer substrate.

Method and composition to minimize dishing


A liquid ejection head includes an electrical wiring substrate and a printing element substrate, wherein the position variation of the printing element substrate due to curing of a sealing agent is eliminated. Specifically, a gap between two support members is covered with the electrical wiring substrate so as to be able to prevent a sealing agent from flowing into the gap. As a result, even in the case where the size of the gap varies due to the variation in the dimensional accuracy and/or the variation in the assembly accuracy, the sealing agent will not enter this gap, and therefore the shape thereof can be made substantially uniform regardless of the positions. This results in a substantially uniform stress in curing and contracting of the sealing agent, and the variation in the mounting position of the printing element substrate can be suppressed.

1. Field of the Invention
The present invention relates to liquid ejection heads and liquid ejection apparatuses, and more specifically, relates to a parts arrangement in an electrical wiring substrate for supplying an electric signal to a printing element substrate for ejecting liquid, such as ink, in the liquid ejection head.
2. Description of the Related Art
In the liquid ejection head, an electrothermal conversion element is used as a printing element that generates energy for ejecting liquid. The electrical wiring substrate for supplying an electric signal to this electrothermal conversion element is provided corresponding to the printing element substrate having the electrothermal conversion elements arranged therein.
Japanese Patent No. 4757011 describes a long line-type liquid ejection head including a plurality of printing element substrates arranged on a support substrate. In this liquid ejection head, the plurality of printing element substrates is arranged in a staggered form along the direction of arranging their ejection ports. In the electrical wiring substrate used here, a single electrical wiring substrate has respective openings for incorporating the plurality of printing element substrates. Moreover, US Patent Laid-Open No. 2005/0162466 describes a liquid ejection head including a plurality of head modules mounted on a support member. In the individual head module, a printing element substrate is mounted on a flow path member and an individual electrical wiring substrate is provided around the printing element substrate.
However, the arrangements of the electrical wiring substrate described in Japanese Patent No. 4757011 and US Patent Laid-Open No. 2005/0162466 have a problem that particularly the position of the printing element substrate may deviate from a desired position due to a sealing member for sealing an electrical connecting portion between the electrical wiring substrate and the printing element substrate.
Specifically, in manufacturing the liquid ejection head, first, the printing element substrate and the electrical wiring substrate are bonded and fixed onto the support member, and these substrates are electrically connected to each other by using wires. Then, a sealing agent is applied to this connecting portion and the resulting portion is heated to cure the sealing agent. Furthermore, after curing the sealing agent, the liquid ejection head is taken out from a heating furnace and cooled. The electrical wiring substrate expands and contracts due to heating and cooling for curing the sealing agent in such a manufacturing process. That is, during heating, the sealing agent is cured in the state where the electrical wiring substrate extends, and the electrical wiring substrate will contract due to the subsequent cooling. In this process, the support member and the printing element substrate experience the stresses of extension and compression and thereby the position of the printing element substrate may vary. Such a liquid ejection head including the printing element substrate whose position has deviated might cause a problem, for example, that the printing image quality degrades.

Liquid ejection head in which positional relationships of elements are not affected by curing of bonding adhesive


A wellhead assembly comprises an outer housing having a central bore therethrough and an inner housing having a central bore therethrough secured in the central bore of the outer housing. The inner housing has a first end within the outer housing. A first inner casing having a central bore therethrough is secured at a first end in the outer housing and spaced from the first end of the inner housing. A port is provided through the outer housing in communication with the central bore therethrough, the port opening into the central bore of the outer housing between the first end of the inner housing and the first end of the first inner casing. A second inner casing is secured in the wellhead assembly at a first end, whereby the port opens into the central bore of the outer housing between the first end of the first inner housing and the first end of the second inner housing. An annulus is formed between the first and second inner casings. A flowpath for fluid injection into a well in which the wellhead assembly is installed comprises the port in the outer housing and the annulus between the first and second inner casings. A method for injecting fluid into the wellhead assembly and the well along the aforementioned flowpath is also provided. The wellhead assembly and method are particularly suitable for the injection of a slurry of drilling cuttings into the well and underground formations into which the well extends.

The present invention relates to a wellhead assembly for injecting a fluid, in particular a slurry of cuttings from a well drilling operation, into a well and a method for its use. The well is especially a subsea well. The method and apparatus of the present invention may be applied in, but are not limited to, the disposal of drilling muds and drilling cuttings prepared in the form of a liquid slurry.
The drilling of an oil or gas well, for example a subsea well, results in the formation of small fragments of rock and other matter, known as cuttings, from the various formations through which the well is drilled. The cuttings are removed from the well as they are formed by the drill bit by being entrained in a drilling mud pumped down the well and returned to the surface vessel or platform. The cuttings are typically recovered from the drilling mud by a separation process and the mud reused in the well operations. In the past, at offshore locations, it has been common practice to dispose of the cuttings separated from the drilling mud in this way by dumping them in the sea. This practice has proven acceptable in the past, as the drilling muds employed were water based in composition and, as such, cuttings separated from such water based slurries gave rise to minimal, if any, environmental impact when disposed of in the aforementioned manner. Additionally, many companies have changed their practice to use synthetic drilling mud that is environmentally friendly.
Recently, however, it has become favoured to employ oil based drilling muds, as such mud formulations offer a number of advantages. For example, oil based muds improve the stability of the well bore, improve the performance of the drill bit by providing better lubrication and removal of cuttings as they are formed, and reduce the torque generated in the drill string during use. For these reasons, oil based drilling muds have been finding increasing use. While offering advantages during the drilling operation, the oil based mud formulations present a problem with respect to disposal. Cutting separated from the oil based muds after recovery from the well are inevitably contaminated with the oil based formulation. Washing the cuttings has been attempted, but only removes the mud from the surface of the cuttings particles, leaving oil in the cracks and pores of the fragments. It is no longer possible to dispose of cuttings recovered from an offshore well using oil based drilling muds in the same manner as when water based muds are employed by simply pouring the cuttings into the sea, due to a damaging environmental impact. The corresponding environmental regulations now prohibit this method of disposal.
Accordingly, it has been the practice to dispose of the cuttings by injecting them into a well and into subsurface formations. To facilitate this, it has been the practice to grind the cuttings and suspend them in a suitable liquid to form a pumpable slurry, which may then be injected into a subsurface formation through an annulus between adjacent casings in the well. This has been common practice in environmentally sensitive areas, such as the north slope of Alaska, for many years.
U.S. Pat. No. 4,942,929 discloses a method for the disposal and reclamation of drilling wastes, in which construction grade gravel is separated from drilling cuttings produced during well drilling operations. The solids that are not so recovered are formed as a slurry with the remaining clays, silts and spent drilling fluid and conducted to a second well, remote from the well being drilled, into which the slurry is injected. Centrifugal pumps or mechanical agitators are used to disperse the fine solids in the slurry to assist in the injection process.
A drill cutting disposal method and system is disclosed in U.S. Pat. No. 5,129,469. In the method and system disclosed, drill cuttings produced during well drilling operations are brought to the surface and separated from the drilling mud, mixed with a suitable liquid, such as sea water and the mixture subjected to grinding to form a slurry. The slurry may then be pumped into a selected zone of the well for disposal.
U.S. Pat. No. 5,341,882 discloses a method for the disposal of well drilling cuttings, in which the cuttings are solidified by combining the cuttings with water and blast furnace slag. The resulting mixture is injected into the annulus between two wellbore casings, where it solidifies to form a cement.
U.S. Pat. No. 5,255,745 describes a method and apparatus for providing a remotely operable connection to establish access to an annulus within a wellhead assembly. The apparatus requires a port in the wellhead assembly. A valve is positioned to seal with the port by remote means using a ramp assembly supported on a guide base positioned around the wellhead.
U.S. Pat. No. 5,884,715 discloses a method and apparatus for injecting cuttings into a well while drilling operations are in progress. Two embodiments are discussed in the disclosure. The first method requires a predrilled well bore to be bored adjacent to and extending away from the well being drilled. The predrilled well bore is used as a depository for the drilling cuttings produced from the well being drilled. The second embodiment requires an injection tube to be installed within the well being drilled alongside the casings set into the well, through which access can be gained to subsurface formations into which the cuttings may be injected. A further embodiment employs an annulus between adjacent casings in the well in order to gain access to underground formations. It is noted that the embodiments disclosed in U.S. Pat. No. 5,884,715 relate to the injection of cuttings into a well having a wellhead accessible on land. While subsea operations are mentioned, little information is given regarding the injection of cuttings into subsea wells.
A subsea wellhead typically comprises a conductor pipe extending below the sea bed in the well, the upper portion of which extends from the well and forms a conductor housing. A high pressure housing is landed in the conductor housing, on which is typically mounted a blowout preventer (BOP) stack by means of a BOP guide funnel. Successively smaller casings are landed in the wellhead, suspended from casing hangers secured within the conductor pipe or the high pressure housing. A guide base is often employed, which comprises a structure extending around the wellhead and mounted to the conductor housing.
A subsea well injection system is disclosed in U.S. Pat. No. 5,085,277, for injecting unwanted slurries and other fluids arising from drilling or other downhole operations into a subsea well. The slurry or other fluid is injected through a drilling guide base positioned around the well on an underwater surface. The system employs a dedicated guide base, which comprises pipework on the guide base leading to a port in the conductor housing of the well, thus gaining access to the annulus between the conductor casing and the adjacent inner casing. A fail safe isolation valve is provided on the guide base and joined to the pipework. A coupling is provided to connect the isolation valve to a surface vessel or platform. The wellhead is modified to provide a port in the conductor housing, in order to gain access to an annulus between casings within the well. With a single port in the outermost housing of the well, fluids may be injected into the outermost annulus of the well. If access is required to an inner annulus, similar ports are required in the casings disposed radially outwards of the inner annulus to provide a flow path to the pipework extending from the guide base.
In U.S. Pat. No. 5,339,912, there is disclosed a cuttings disposal system in which an injection adapter is employed to allow a slurry of cuttings to be injected into a well. The well, designated an xe2x80x9cinjection wellxe2x80x9d, has an inner and an outer wellhead housing with at least one casing hanger and a respective inner casing installed in the inner wellhead housing. The casing hanger is formed with a port through it, connecting the bore of the well with the annulus between the inner casing and the outer casing of the well. When it is desired to inject cuttings into the well, an injection adapter is landed in the wellhead so as to extend into the bore of the well, allowing a central bore in the injection adapter to connect, through a port in the side of the injection adapter body, with the port in the casing hanger. The central bore in the injection adapter is connected by pipework to a pump at the surface, by means of which a slurry of cuttings may be injected through the injection adapter and into the annulus in the well. It is noted that, with the injection adapter landed in the well, access to the well for conducting other operations is denied, until the cuttings injection operation is ceased and the injection adapter removed.
In a paper entitled xe2x80x9cSubsea Cuttings Injection Guide Base Trialxe2x80x9d presented at the Offshore European Conference, Sep. 7 to 10, 1993, Ferguson et al. disclosed the results of field trials conducted to test a permanent guide base and wellhead assembly modified to allow cuttings injection. A modified permanent guide base was employed having a pipe connecting through the guide base to a port in an extension welded to the conductor housing of the wellhead. A similar extension was provided on the lower end of the high pressure housing, through which a port was formed to align with the port in the extension to the conductor housing and provide access to an inner annulus of the wellhead assembly. As with the system of U.S. Pat. No. 5,662,169, a dedicated guide base is required in this system in order to provide the possibility of cuttings injection, together with modifications to several of the wellhead components.
A similar cuttings injection system is disclosed by Saasen et al. in a paper entitled xe2x80x9cThe First Cuttings Injection Operation Worldwide in a Subsea Annulus: Equipment and Operational Experiencexe2x80x9d, presented at the SPE Annual Technical Conference and Exhibition, Sep. 27 to 30, 1998. Saasen et al. indicate that prior to 1998 cuttings re-injection had been restricted to fixed platforms. Saasen et al. state that annular re-injection into subsea wells, where drilling operations are in progress had not been feasible. Accordingly, Saasen et al. report on a new development to provide a system to achieve cuttings re-injection, while drilling operations are taking place. The system employs a modified guide base, required to be larger than conventional guide bases, through which access is gained to a port formed in the conductor housing. A similar port is provided in the high pressure housing, aligned with the port in the conductor housing, in order to access an annulus between the high pressure housing, and its associated casing, and a casing suspended from a casing hanger secured in the bore of the high pressure housing. Again, the system of Saasen et al. requires a modified, dedicated guide base to be provided in order to inject cuttings into an annulus within the wellhead assembly. Further, in the system of Saasen et al. seal cartridges are required to be provided within the conductor housing around the high pressure housing both above and below the ports in the conductor housing and high pressure housing, in order to avoid ingress of the cuttings slurry into the annulus between the conductor housing and the high pressure housing.
As can be seen from the above review of the prior art, wellhead assemblies have been proposed which employ a guide base having one or more ports which align axially, and in some cases circumferentially, with corresponding ports in the conductor housing, in order to gain access to an annulus within the well. Saasen et al. indicate that the only practical application of cuttings re-injection into a well while drilling operations are taking place requires a dedicated guide base, having ports which connect with ports in the wellhead housing. It would be advantageous if way could be found to dispense with the need to provide ports in the guide base, thus reducing the overall number of seals required, with a corresponding reduction in the possibility of a failure of the system resulting in a leak.
A cuttings injection wellhead system for use in subsea wells is disclosed in U.S. Pat. No. 5,662,169. The wellhead system employs a wellhead having a conductor casing, to which is mounted a conductor housing and around which a guide base is provided. A high pressure housing is landed in the conductor housing. The wellhead system comprises an extension to the conductor housing extending between the lower end of the conductor housing and the conductor casing. A port is formed in the conductor housing extension below the guide base, allowing access to the interior of the conductor housing. A similar extension is provided on the lower end of the high pressure housing, formed with a corresponding port aligned with the port in the conductor casing. An inner casing is suspended from a casing hanger disposed within the high pressure housing. The ports in the extensions to the conductor housing and high pressure housing provide access to the annulus around the inner casing, into which a slurry of drilling cuttings may be injected. The pipework necessary to connect with the port in the conductor housing extension depends from the guide base provided around the wellhead assembly.
The wellhead system of U.S. Pat. No. 5,662,169 does not employ ports in the guide base, in order to gain access to an annulus within the wellhead and the well. However, the assembly of U.S. Pat. No. 5,662,169 requires the use of a modified conductor housing and high pressure housing, both of which must be provided with extensions through which aligned ports must be bored. In addition, the system of U.S. Pat. No. 5,662,169 requires the use of a dedicated guide base with the necessary pipework and connections in order to allow cuttings injection to proceed.
It is noted that the prior art teaches, in general, that it is required to employ a dedicated guide base in order to effect cuttings injection into a subsea wellhead. However, as wells are being drilled in deeper and deeper water, it is becoming increasingly difficult to employ a guide base. In very deep water, it is very difficult, if not impossible, to support and properly orient a guide base on a wellhead assembly from the surface. Accordingly, there is a need in the art to provide a system for injecting cuttings and other fluids into a well, without being required to rely upon a guide base, whether of conventional design or dedicated to allow for fluid re-injection.
Further, it can be seen that the systems proposed in the prior art require significant modifications to the components of the wellhead assembly in order to provide access to the annulus of choice within the well. It would be advantageous to provide a system for fluid injection requiring only a minimum of modifications to conventional wellhead assembly components.
It would be of further advantage if the system for cuttings injection could be operated in a well while drilling and other well operations were proceeding at the same time.
According to a first aspect of the present invention there is provided a wellhead assembly comprising:
an outer housing having a central bore therethrough;
an inner housing having a central bore therethrough and secured in the central bore of the outer housing, the inner housing having a first end within the outer housing;
a first inner casing having a central bore therethrough, the first inner casing being secured at a first end in the outer housing and spaced from the first end of the inner housing;
a port through the outer housing in communication with the central bore therethrough, the port opening into the central bore of the outer housing between the first end of the inner housing and the first end of the first inner casing;
a second inner casing secured in the wellhead assembly at a first end, whereby the port opens into the central bore of the outer housing between the first end of the first inner housing and the first end of the second inner housing, an annulus being formed between the first and second inner casings;
whereby a flowpath for fluid injection into a well in which the wellhead assembly is installed comprises the port in the outer housing and the annulus between the first and second inner casings.
A wellhead assembly according to the present invention allows access to be gained to an annulus between casings within the wellhead assembly and the well, into which a fluid may be injected, with a minimum of seals being required and a minimum of modifications being needed to existing or conventional wellhead assembly components. Further, the wellhead assembly allows fluid to be injected into the wellhead assembly and the well, while downhole operations such as drilling, are being conducted through the second inner casing.
The second inner casing is preferably secured at its first end within the central bore of the inner housing. In this arrangement, a collar is preferably disposed to extend from the first end of the inner housing between the opening of the port in the outer housing and the second inner casing. In this way, fluid injected into the wellhead assembly through the port is not allowed to impact the second inner casing, but rather is deflected to flow more longitudinally within the central bore of the outer housing.
A third inner casing is preferably provided, disposed to extend within the second inner casing and secured within the wellhead assembly. In this way, downhole operations may be conducted through the third inner casing, with at least one casing disposed between the third inner casing, the central bore of which is at well pressure, and the flowpath through which fluid is injected.
In a preferred embodiment, an intermediate casing is disposed within the wellhead assembly so as to extend within the first inner casing, in the annulus between the first inner casing and the second inner casing. The intermediate casing is preferably secured at a first end to the first inner casing in the annulus between the first and second inner casings. In such an arrangement, the first end of the intermediate casing may be sealed to the first inner casing, thereby ensuring fluid introduced into the wellhead assembly along the flowpath flows along the annulus between the intermediate inner casing and the second inner casing.
Preferably, a means for deflecting the flow of fluid entering the wellhead assembly through the port in the outer housing is deflected, so as not to impinge directly upon the second inner casing. As noted above, when the second inner casing is secured at one end within the inner housing, the means for deflecting the flow of fluid may be a collar extending from the first end of the inner housing. As an alternative, or in addition thereto, a sleeve may be provided to extend between the opening of the port in the outer housing and the second inner casing.
Fluid is preferably introduced into the wellhead assembly by means of a riser interface assembly connected to the port in the outer housing. The riser interface allows a riser to be connected between the port in the outer housing and a surface platform or vessel, through which fluid may be pumped into the well. The riser interface preferably comprises a valve for regulating the flow of fluid along the flowpath. The valve is most preferably a fail-safe closed valve, allowing the port and the interior of the outer housing to be sealed in the case of an emergency.
In a further aspect, the present invention provides a method for injecting a fluid into a well, which method comprises:
providing a wellhead assembly having an outer housing having a central bore therethrough and an inner housing secured within the central bore of the outer housing;
introducing a fluid into the central bore of the outer housing of the wellhead assembly at a point below the inner housing; and
allowing the fluid to enter an annulus formed between a first inner casing secured at a first end in the wellhead assembly below the point of introduction of the fluid and a second inner casing secured at a first end above the point of introduction of the fluid;
the annulus extending between the first and second inner casings into the well.
The fluid is preferably introduced into the central bore of the outer housing through a port in the outer housing.
Once introduced into the outer housing, the fluid is preferably deflected in the region of the point of introduction, in order to prevent the fluid impinging directly upon the second inner casing. The deflection may be accomplished by having a collar extending from the inner housing between the point of introduction of the fluid and the second inner casing. As an alternative, or in addition thereto, a sleeve may be located in the central bore of the outer housing between the point of introduction of the fluid and the second inner casing.
The annulus entered by the fluid may be formed by an intermediate inner casing extending between the first inner casing and the second inner casing. In such an arrangement, the annulus entered by the fluid is preferably formed between the intermediate casing and the second inner casing. When an intermediate casing is provided, it is preferably secured in the first inner casing to thereby seal the annulus between the first inner casing and the intermediate casing.
The fluid being introduced into the wellhead assembly and the well may be any fluid which is required to be injected into the well. The method of the present invention is particularly suitable for use in the injection into a well of a slurry of drilling cuttings. In a most convenient embodiment of the present invention, the drilling cuttings have been produced by drilling operations conducted within the well. In other words, the present invention provides for the re-injection into a well of drilling cuttings produced from the well during drilling operations conducted in the well. This method represents a most efficient and cost-effective method of disposing of drilling cuttings produced during offshore drilling operations.
It is a further aspect of the present invention that the injection of fluid, in particular a slurry of drilling cuttings, into the wellhead assembly and the well may be carried out at the same time as well operations are being conducted through the second inner casing. In particular, the present invention allows for drilling operations to be performed and drilling cuttings produced as a result of the drilling operations simultaneously re-injected into the well.
Specific embodiments of the apparatus and method of the present invention will now be described in detail having reference to the accompanying drawings. The detailed description of these embodiments and the referenced drawings are by way of example only and are not intended to limit the scope of the present invention.

Wellhead assembly for injecting a fluid into a well and method of using the same


A fuel pump module and method are provided for installation into a low profile fuel tank. A reservoir holds a substantially horizontally mounted fuel pump. A flange is mounted to the fuel tank to support the module. A link is pinned at one end to the flange and is pinned at a second end to the reservoir to provide a pair of articulable connections therebetween. A pair of springs urge separation between the link, reservoir and flange.

1. Field of the Invention
This invention relates to the field of fuel delivery modules for an automotive vehicle and more particularly to a horizontally mounted fuel module in a low profile fuel tank.
2. Discussion of the Prior Art
A fuel module may be mounted to the fuel tank of an automotive vehicle. In such an application, it is known to mount the module from an opening in the top of the fuel tank. A flange is provided on the module assembly to support the assembly to the tank.
Due to variations in the height of the fuel tank and variations in the height of the fuel module, it is necessary to provide a means to adapt the height of the fuel module to properly position the module assembly in the tank. Such proper positioning enables accurate measurement of the level of fuel in the fuel tank and enables proper positioning of the input to the fuel pump.
An example of a means to adapt the height of a vertically mounted module is provided in U.S. Pat. No. 4,945,884 ('884 patent). As shown in FIGS. 1 and 3 of the '884 patent, vertical guides 76 are provided to support the pump and reservoir assembly 22 with respect to the module flange 46 that is mounted to the fuel tank 10. A plurality of helical springs 88 are compressed between the reservoir 22 and flange 46 to urge the pump vertically downwardly toward the bottom of the tank 10. The arrangement described in the '884 patent provides for a vertically oriented fuel pump, which requires more vertical height than which is available in many applications.
An example of a horizontally mounted pump is described in U.S. Pat. No. 5,669,359 ('359 patent). The '359 patent provides a single rod 39 which acts to support the fuel pump and bias the pump downwardly toward the bottom of the fuel tank. This single rod 39 serves both functions of support and deflection. The rod 39 is limited in the amount of deflection which it can provide before plastic deformation or fracture occurs in the rod and is limited in the manner in which the rod is able to articulate as it bends. Therefore the module of the '359 patent may not articulate adequately to facilitate installation through a hole in the top of a low profile fuel tank.
It would therefore be desirable to provide a module which enables installation in a low profile fuel tank through a hole provided in the top of the fuel tank by articulating the module during installation and urging the module into engagement with the bottom of the fuel tank.


A wall clock has a first time increment portion comprising a stationary frame member. A timepiece movement is supported by the stationary frame member. A first wheel is rotatably driven by the timepiece movement, and a first time indicating member is rotatably driven by the timepiece movement for indicating a first time increment (i.e., hours). A belt is disposed around and driven by the first wheel. A second time increment portion rotatably supports a second wheel. The second wheel is rotatably driven by and suspended only by the belt, so that the second time increment portion is suspended only by the belt. A second time indicating member is rotatably driven by the second wheel for indicating a second time increment (i.e., minutes). The diameters of the first wheel and second wheel have a ratio of 12:1 so that the single timepiece movement can drive both the hour time indicating member (hour hand) and the minute time indicating member (minute hand) at appropriate speeds, through a simple and easy to manufacture construction.

1. Field of Industrial Use
The present device relates to a wall clock.
2. Prior Art
The conventional wall clock is constructed such that when it is hung on a wall or the like, a dial is fixed within a clock frame and two hands respectively fixed to their shafts extending from a timepiece movement behind the dial are rotated on the front surface of the dial, thereby displaying time.
The conventional wall clock of the above construction is excellent for display in time, but lacks interest of design because it has only a single lacks dial with hour and minute hands thereof rotating concentrically.


An inner barrel assembly for use with a coring tool may include a sleeve located coaxially within an inner barrel in a telescoping manner. The core barrel assembly may also include a cap located above a top end of the sleeve when the inner barrel assembly is in an initial coring position. The cap may include a skirt having a portion extending downwardly from the cap. A coring tool including an inner barrel assembly and methods of forming an inner barrel assembly are also disclosed.

When seeking information regarding the characteristics of an earth formation, such as, for example, the degree to which it is saturated in hydrocarbons, a core sample may be obtained from the earth formation. The core sample may then be analyzed to determine the characteristics of the earth formation. Core samples may be obtained using coring tools. A coring tool may include an inner barrel assembly located with an outer barrel in a manner such that the outer barrel, having a core bit at a bottom thereof, may rotate about a longitudinal axis of the coring tool while an inner barrel, having an inner bore for receiving the core sample, remains substantially rotationally stationary within the outer barrel. The core bit may include an inner bore and a cutting structure surrounding the inner bore. In many instances, the outer barrel is assembled section by section into a pre-drilled wellbore, and thereafter the inner barrel assembly is assembled section by section within the outer barrel until the inner barrel assembly is fully assembled and located in a longitudinally fixed but rotationally free, fully operational "coring" position relative to the outer barrel.
As the coring tool is driven into an earth formation, the core bit may remove earth material around a core sample, which is received into the inner bore. The inner barrel may extend longitudinally above the inner bore of the core bit. The core sample may be received into the inner barrel, and may be retained in the inner barrel by a core catcher to keep the core sample within the inner barrel as the coring tool is withdrawn from the borehole. As the core sample extends into the inner barrel, the core sample may contact a portion of the inner barrel and cause a significant increase in friction between the core sample and the inner barrel or even completely lock the core sample to the inner barrel. Such occurrences are often referred to in the art as "jamming." When jamming occurs during a coring operation, the operation must be terminated and the drill string tripped out from the wellbore. Jams may be caused by a number of factors. For example, a condition known in the art as "formation fault slant" may cause a wedging jam between the core sample and the inner barrel. Additionally, jams may be caused by collapse of unconsolidated core material or expansion of clay or other materials inside the core sample. In some instances, jams occur undetected, resulting in the core sample failing to enter the inner barrel as the coring tool continues to engage uncut formation material. In such instances, the core sample may inadvertently be destroyed as the jammed portion of the inner barrel grinds or mills away the core sample as the coring tool progresses downward into the formation. The information obtained from core samples is valuable for understanding the subterranean formation properties and conditions. Thus, jams resulting in a shortened coring run and/or a destroyed core sample and/or a core sample shorter than the maximum retrievable length result in loss of information, time and money.

Coring tools with improved reliability during core jams, and related methods


A method and an image evaluation unit are disclosed for recognizing and marking contrast agents in blood vessels of the lung with the aid of a CT examination using at least two different x-ray energy spectra. In at least one embodiment, the method includes scanning a patient at least in the region of the lung with two different x-ray energy spectra, with the patient having contrast agents in the blood stream; reconstructing an at least two or three dimensional tomographic display for each x-ray energy spectrum which reproduces the local spectrum-specific absorption properties of the scanned region, wherein a surrounding area is defined for a multiplicity of voxels for which an average ratio is calculated with the aid of the local absorption values of the at least two x-ray energy spectra, which surrounding area specifies a measure for the ratio of the proportion of contrast agent to the proportion of soft tissue in the surrounding area of the respectively considered voxel, and wherein, in the case of this ratio dropping below a threshold value, this voxel is considered to have reduced circulation and is marked in a tomographic display.

By way of example, a method is described in the patent application US 2004/0101089 A1, the entire contents of which are hereby incorporated herein by reference.
When examining lung tissue, it is sometimes medically necessary to also evaluate the circulatory state of thin blood vessels. Due to partial volume effects, this evaluation is difficult using reconstructed CT images which display HU values, especially in the case of fine lung vessels. The HU values in the interior of the vessel calculated in the process depend inter alia on the vessel diameter, the reconstruction kernel and, if applicable, also on the slice thickness of the reconstructed slice images.
If the vessels are very thin, partial volume effects prevent a clear display of vessels supplied with contrast agent. In this case, these partial volume effects have effective diameters which can be significantly larger than the pixel diameter or voxel diameter of a CT image.

Method for recognizing and marking contrast agents in blood vessels of the lung with the aid of a CT examination and an image evaluation unit of a CT system


There is provided a communication system, comprising a network infrastructure comprising: a transmitter configured to transmit signaling information to user terminals, the signaling information being related to the allocation of the plurality of sub-carriers at a common frequency band used for data transmission between the multiple user terminals and a network infrastructure; a processor configured to divide the common frequency band into two suppression bands at the edge zones of the common frequency band and to provide a safe band between the two suppression bands, the two suppression bands including sub-carriers having a predetermined amount of decreased channel estimation accuracy compared with the other sub-carriers of the common frequency band; and a processor configured to allocate signaling information, related to the allocation of at least one sub-carrier to a user terminal having an expected signal to interference-plus-noise ratio at a predetermined level, to at least one sub-carrier included in the safe band.

In known communication systems, such as systems based on orthogonal frequency division multiple access (OFDMA), a common frequency band is shared among many user terminals. The user terminals often monitor the shared channel resources of the system in order to transmit and receive data efficiently. The user terminals receive signaling information related to allocation of the user terminals to specific resources of the common frequency band for transmission and/or reception. An Allocation Table or a corresponding control channel (e.g. a shared control channel) is used to describe the allocation of user data both in downlink and uplink. The Allocation Table can be sent once per a short period of time, i.e. a subframe of transmission time interval (TTI), for example. This is important in order to control packet-switched traffic and the scheduling thereof efficiently.
In a known system, the Allocation Table is transmitted as one self-decodable block for all user terminals. As the block is transmitted over the whole bandwidth, it benefits from the available frequency diversity. However, such a block should be coded and modulated taking into account the lowest signal to interference-plus-noise ratio (SINR) requirements. The performance in such a case is not satisfactory at low SINR and it also consumes radio resources excessively due to a large Information Block length and a low channel-coding rate.
Some methods have been proposed for improving the performance of control channel reception. First, instead of one decodable block the user terminals can be divided into several groups according to their reported SINR. Then, a modulation and coding rate of such blocks can be adjusted respectively. The Allocation Table for user terminals in difficult signal conditions can be coded with low code rate and low order modulation. Further, the transmitted power of the blocks can be differentiated such that higher power is allocated to user terminals having low SINR for improving the reliability in that area. The blocks can be allocated not only as chunk of consecutive sub-carriers but also in a distributed (scattered) manner so that all separately decodable blocks also benefit from frequency diversity. Further, as an alternative, the shared control channel may be arranged as a set of self-decodable information blocks, each of which is intended for a user terminal separately. This kind of shared channel has roughly the same properties as the Allocation Table described above but with a receiver-specific power control (power boosting/power suppression), code rate selection and smaller Information Block Length. Also in this case, the code blocks are distributed (scattered) over a frequency to benefit from frequency diversity.
Receiving of the Allocation Table (i.e. the allocation information) is important because if a user terminal does not succeed in that, it cannot receive any data either. The probability of receiving the Allocation Table should be good in order to guarantee good capacity of the particular radio link. The reception should also work well with a low SINR. Especially at low SINR values, it is difficult to achieve reliable reception of allocation information.


An apparatus for protecting the exposed top portion of human arms, one or both, from the sun's rays. A two piece fabric, which may have a SPF of at least 15, covers at most the top half of the arm is supported by spaced first and second elastic bands or straps, one of which encircles the wrist area and the other at the forearm forward of the elbow, leaving the forearm beneath the fabric to receive the free flow of cooling air around and under the flexible fabric portion. The two pieces are connected by adjustable hook and loop to allow for length adjustment. A swivel connection member between that portion of the piece adjacent the elbow and the second strap prevents curling or strain on the fabric when the forearm is bent about the elbow. One embodiment includes a single piece fabric with the swivel connection described.

Most who work in the open air usually wear short sleeves shirts leaving the forearms exposed. One of the basic problems confronting those who work, or play with their forearms exposed, is sunburn or the possibility of other skin diseases caused by the sun's rays. On the other hand it is also desirable to keep the arms as cool as possible.
Within just five minutes on a sunny summer day one's skin may absorb enough UV radiation to develop a minor sunburn. Skin cells may suffer injury that can not be seen or felt. Multiply that over the years and damage from daily sun exposure may become major, including skin cancer and skin aging. In recent years, the public has become more aware of the effects of melanoma and the prevention and treatment thereof.
There are two types of ultraviolet rays-UVA (long wave solar rays of 320-400 nanometers) and UVB (short wave solar rays of 290-320 nanometers)—that can affect the skin even with small daily doses. The UVB rays are most abundant in the midday sun, usually from 10 a.m. to 4 p.m., when your shadow is shorter than a person, and are most associated with sunburn. The medical community, recommends full head-to-toe protection of at least SPF (Sun Protection Factor) of 15, and preferably 30+. SPF or UPF (Ultra Violet Protection Factor) is meant to be a guide of how much time you can spend in the sun compared to how long the skin takes to redden without protection. Liquid sun screens, although effective, are troublesome to use and are not always effective against harmful UVA radiation. It is known that most people don't apply the recommended doses of sun screen and/or don't like the mess. For more information refer to the Internet at <www.skincancer.org>.
A UV blocking fabric is found in U.S. Pat. No. 6,037,280.
Others have tried to seek protection of their arms by tubular sleeves that surround the arm and in some instances up to and including the shoulder. Some representative samples of such garments can be found in the following U.S. patents:                U.S. Pat. No. 5,357,633 Rael; U.S. Pat. No. 5,628,062 Tseng; U.S. Pat. No. 5,974,586 Reinoso; and U.S. Pat. No. 6,539,550 Flores.
However, these devices, although they teach sun protective concepts, are tubular in construction being designed to fully cover the arm and in the instance of the Rael, Flores and Reinoso to include the upper arm and shoulder. Such devices would not be comfortable in the heat of summer as there is no free flow of air around the exposed limbs.
Other forms of devices to protect the arms and/or shoulders for different, or unexplained, reasons are found in the following U.S. patents                U.S. Pat. No. 1,141,656 Rosenbaum, et al.; U.S. Pat. No. 1,157,341 Tallerday; U.S. Pat. No. 5,511,241 Ziegler; U.S. Pat. No. 5,734,992 Ross; U.S. Pat. No. 6,405,381 Bowman, Jr.; U.S. Pat. No. 6,449,772 Donner; and U.S. Pat. No. 6,472,590 Kulik.
There are in the prior art devices for partially covering the arm as shown in the following U.S. patents:                U.S. Pat. No. 794,294 Gardner; U.S. Pat. No. 925,952 Sacks; U.S. Pat. No. 5,056,157 Pryor; and U.S. Pat. No. 6,243,867 Faison
Gardner and Sacks describe devices for protecting the underside of sleeve covered arms such as during indoor desk work.
The Pryor and Faison patents describe devices for protecting the upper forearm from solar radiation, but like the prior art utilizes a plurality of VELCRO straps to releasably secure the fabric. To permit free flow of air, as when the arm is outside the window of a vehicle, these straps must be loose fitting which could allow the device to move about the arm. To prevent that, the straps must then be tight around the arm, which then will restricting the free flow of air around the arm.
One problem with certain prior art devices is that when the forearm is pivoted about the elbow joint, as for example, moved upward and/or inward, the covering becomes unattractive as it moves, twists or curls, and exposes the forearm. The use of a swivel connection means adjacent the elbow joint, as disclosed herein, prevents such moving or twisting of the protective covering.
Although protecting the arm which projects outwardly of a vehicle is still possible, the modern day vehicle is usually air cooled with the windows closed. There are, however, many other situations where protection is needed. Construction laborers, service personnel, and even those who work and attend outdoor sports or other events could use protective devices.
It is therefore an object of the invention to provide a garment device for protecting one or both forearms of individuals from the harmful effects of the sun.
It is another object of the invention to provide a device that not only protects the forearm of individuals but is comfortable and cooler. The distinctive feature being a length, or an adjustable length, of flexible sun blocking fabric that is loosely fitted over at least the top portion of the forearm between two elastic bands or adjustable straps, one at the wrist, the other forward of the elbow joint and bone.
Another object of the invention is the use of a medically acceptable fabric providing high SPF, UVA and UVB sun protection such as that sold under the trademark SOLUMBRA, a product of Sun Precautions, Inc. Other fabrics of Solar Protective Factory, Inc sold under the trademarks SOLARWEAVE and SUN RePel are inclusive of use. Such fabrics are advertised to provide 30+ SPF protection.
A further object of the invention is to provide a fabric covering that includes ornamental designs or promotional advertising on the outside.


A method for partial cylinder cutoff is provided. The method comprises operating a multi-cylinder internal combustion engine with applied ignition, in which an odd number n of cylinders is arranged in line, and during partial-load operation when engine load is below threshold, enabling a partial cutoff of the cylinders, the partial cutoff comprising operating each cylinder only intermittently such that each cylinder is fired and cut off in turn at an interval of (2*720° CA)/n.

Spark-ignition engines operate with a homogeneous fuel-air mixture which, in the absence of direct injection, is prepared through external mixture formation by introducing fuel into the intake air in the intake tract. The required power output is adjusted by varying the combustion chamber charge so that, unlike in the diesel engine, operation of the spark-ignition engine is based on a quantitative control.
The load is generally controlled by means of a throttle valve provided in the intake tract. By adjusting the throttle valve the pressure of the intake air downstream of the throttle valve can be reduced to a greater or lesser degree. The further the throttle valve is closed, the greater the pressure loss of the intake air over the throttle valve and the lower the pressure of the intake air downstream of the throttle valve and upstream of the inlet to the cylinder. Given a constant combustion chamber volume it is possible in this way to adjust the air mass, that is to say the quantity, by way of the intake air pressure. However, in the partial load range, since small loads require a high degree of throttling and pressure reduction in the intake tract, charge cycle losses increase as the load diminishes and the throttling increases. As a result, engine efficiency and thus fuel economy are compromised.
Various strategies have been developed for dethrottling an internal combustion engine with applied ignition, in order to reduce the losses described. Since in partial load operation the spark-ignition engine has a poor efficiency due to the throttle control, whereas the diesel engine has a greater efficiency, attempts have been made to combine the two methods of operation with one another, in order to exploit the advantages of the diesel engine method for the benefit of the spark-ignition engine method. Here the development work has concentrated primarily on the essential features of the two methods. The conventional spark-ignition method is characterized by a mixture compression, a homogeneous mixture, an applied ignition, and the quantitative control, whereas the conventional diesel engine method is characterized by an air compression, an inhomogeneous mixture, a compression ignition and the qualitative control.
One approach to dethrottling, for example, is to operate the spark-ignition engine with direct injection. Direct fuel injection is a suitable means for achieving a stratified combustion chamber charge. Within certain limits, the direct injection of fuel into the combustion chamber thereby allows a qualitative control in the spark-ignition engine. The mixture formation ensues through the direct injection of fuel into the cylinders or rather the air present in the cylinders and not through external mixture formation, in which the fuel is introduced into the intake air in the intake tract.
Another possible way of optimizing the combustion process of a spark-ignition engine lies in the use of a variable valve gear. In contrast to conventional valve gears, in which both the valve lift and also the timings, that is to say the opening and closing times of the intake and exhaust valves, are predetermined as invariable quantities by the non-adjustable and hence inflexible mechanism of the valve gear, these parameters influencing the combustion process and thereby the fuel consumption can be varied to a greater or lesser degree by means of variable valve gears. A load control with no throttle and thereby no losses is possible simply by being able to vary the closing time of the intake valve and the intake valve lift.
The concepts described above have the disadvantage that they are not suitable for retrofitting to engines already on the market, since they require substantial modifications to the basic engine and/or the valve gear, and additional complex components.
One approach to the dethrottling of spark-ignition engines already on the market is afforded by the cylinder cutoff. This serves to improve, that is to say to increase the efficiency in the partial-load range since the cutoff of one cylinder of a multi-cylinder internal combustion engine increases the load of the cylinders in operation, so that the throttle valve may be opened further in order to introduce a larger air mass into these cylinders, so that overall a dethrottling of the internal combustion engine is achieved. Owing to the larger air mass delivered, the cylinders still being operated during the partial cutoff have an improved mixture formation and tolerate higher exhaust gas recirculation rates. Further advantages in terms of efficiency accrue in that owing to the absence of combustion a cylinder which has been cut off does not generate any heat losses through the wall due the transmission of heat from the combustion gases to the combustion chamber walls.
Besides the aforementioned advantages, partial cutoff, particularly in multi-cylinder internal combustion engines having an odd number n of cylinders, also have disadvantages, which are often an obstacle to use in series production. Conventionally, in an inline three-cylinder engine, for example, one cylinder of the engine is embodied as a cutoff cylinder. In normal operation, that is to say when all three cylinders are in operation and the partial cutoff is deactivated, the cylinders are fired in the firing order 1-2-3 at an interval of 240° CA. In the context of a partial cutoff, the cutoff cylinder is deactivated and only the two remaining cylinders continue to operate, so that an irregular firing pattern ensues, in which the firing interval alternates between 240° CA and 480° CA, which results in several detrimental effects.
The engine structure excited to structure-borne sound oscillations by the impulses and alternating forces emits the structure-borne sound via its engine surfaces as airborne sound and in this way generates the actual engine noise. The irregular firing pattern leads to an unharmonious engine noise, which is perceived as unpleasant. This is disadvantageous, since the noise generated by the internal combustion engine has a considerable influence on customers' purchasing behavior. Further, excitation of the crankshaft in the natural frequency range can result in high rotational oscillation amplitudes, which can even lead to fatigue fracture.
The problems discussed taking a three-cylinder internal combustion engine as an example similarly exist in any multi-cylinder internal combustion engine, in which an odd number n of cylinders is arranged in line, for example also in the case of a five-cylinder internal combustion engine, in which five cylinders are arranged in line.
The inventors herein have recognized the above issues and provide a solution to at least partially address them. Thus, a method for operating a multi-cylinder internal combustion engine with applied ignition having an odd number n of cylinders arranged in line is provided. The method comprises operating a multi-cylinder internal combustion engine with applied ignition, in which an odd number n of cylinders is arranged in line, and, during partial-load operation when engine load is below threshold, enabling a partial cutoff of the cylinders, the partial cutoff comprising operating each cylinder only intermittently such that each cylinder is fired and cut off in turn at an interval of (2*720° CA)/n.
In the method according to the present disclosure, in normal operation, when all n cylinders are being operated and the partial cutoff is deactivated, the n cylinders are fired at a firing interval of approximately 720° CA/n. During the partial cutoff, on the other hand, each cylinder is operated intermittently and in such a way that each cylinder is fired and cut off in turn, so that in partial load operation the cylinders are fired in a modified firing order and at a firing interval of approximately (2*720° CA)/(n). The firing interval therefore doubles with a partial cutoff of the cylinders. The partial cutoff according to the disclosure leads to a uniform firing interval, that is to say to a regular firing pattern, and thereby to a harmonious engine noise.
In a multi-cylinder, in-line engine having an odd number of cylinders and applied ignition, the method for partial cutoff according to the present disclosure makes it possible to reduce the charge cycle losses which are bound to occur due to the quantitative control by means of a throttle valve, whilst avoiding an irregular firing pattern, in which the firing interval varies and which has a detrimental effect on the noise emissions. Thus, dethrottling of the engine can be achieved without having to accept disadvantages in terms of the noise emissions.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

Multi-cylinder internal combustion engine and method for operating a multi-cylinder internal combustion engine