A solid electrolytic capacitor having an electrolytic layer containing at least two types of ionic liquids and a conductive polymer is provided. Preferably, the ionic liquids include at least one type of ionic liquid for supplying an excellent impedance characteristic and at least one type of ionic liquid for supplying an excellent withstand voltage characteristic. Thus, a solid electrolytic capacitor exhibiting a high withstand voltage and an excellent impedance characteristic can be obtained.

1. Field of the Invention
The present invention relates to a conductive polymer solid electrolytic capacitor excellent in withstand voltage characteristic and impedance characteristic.
2. Description of the Background Art
A conductive polymer solid electrolytic capacitor employing a conductive polymer as an electrolyte exhibits an excellent impedance characteristic, and increasingly expands markets. An electrolytic capacitor is generally constituted of an anode metal prepared from a valve metal such as aluminum, tantalum or niobium, a dielectric film formed by an oxide film provided on the surface of the anode metal and a cathode formed through an electrolytic layer provided on the dielectric film. The electrolyte of the electrolytic capacitor has two important functions, i.e., a function of protecting and repairing the extremely thin oxide film and another function of drawing the capacitance from the dielectric film provided on the anode as a de facto cathode. A conductive polymer solid electrolytic capacitor typically employs a conductive polymer such as solid polypyrrole or a polythiophene derivative as an electrolyte. Such a conductive polymer has by far higher electric conductivity (i.e., electronic conductivity) as compared with a liquid electrolyte employed for a general electrolytic capacitor. Therefore, the capacitor employing this conductive polymer as the electrolyte can reduce the internal impedance, and exhibits excellent characteristics particularly as a high-frequency circuit capacitor.
However, the conductive polymer essentially has no ionic conductivity. Therefore, the capacitor employing the conductive polymer as the electrolyte is inferior to a conventional capacitor employing an electrolytic solution in repairability (i.e., anodic oxidation) for the oxide film of the electrolytic capacitor. Consequently, a conductive polymer solid electrolytic capacitor exhibiting a high withstand voltage cannot be manufactured. More specifically, a conductive polymer solid electrolytic capacitor employing aluminum for an anode withstands a voltage of about 16 V in practical use when subjected to 40 V chemical conversion, for example, and a conductive polymer solid electrolytic capacitor employing tantalum withstands a voltage of about 12 V in practical use when subjected to 24 V chemical conversion, for example. In the 40 V chemical conversion, a DC voltage of 40 V is applied when an oxide film of a dielectric substance is formed on the surface of the valve metal, and a capacitor exhibiting a withstand voltage of 40 V must be ideally obtained in this case. While the withstand voltage in practical use can be increased in principle by increasing the chemical conversion voltage, the capacitance is reduced as the chemical conversion voltage is increased in this case. Further, the withstand voltage in practical use is not increased in proportion to the chemical conversion voltage.
Typical electrolytic capacitors include an aluminum electrolytic capacitor employing aluminum as an anode metal and a tantalum electrolytic capacitor employing tantalum as an anode metal. In general, a porous electrode obtained by sintering tantalum powder is employed for the tantalum electrolytic capacitor. On the other hand, aluminum electrolytic capacitors include a chip-type electrolytic capacitor and a wound-type electrolytic capacitor. In order to manufacture the chip-type electrolytic capacitor employing a conductive polymer as an electrolyte, the electrolyte consisting of the conductive polymer is formed on an anode foil made of aluminum by electrolytic polymerization or chemical polymerization, carbon paste and silver paste are thereafter applied, and these components are stacked and dried for preparing a capacitor element. The chip-type electrolytic capacitor manufactured in the aforementioned manner has a remarkably excellent frequency characteristic, while it is extremely difficult to manufacture the element, disadvantageously leading to a high rejection rate. On the other hand, the wound-type electrolytic capacitor employing a conductive polymer as an electrolyte comprises an anode foil of aluminum provided with a dielectric oxide film on the surface thereof, a cathode foil and a separator provided between the cathode foil and the anode foil. After these components are wound, the electrolyte is formed by impregnating and polymerizing a monomer forming the conductive polymer.
While the separator is indispensable in order to prevent the wound-type electrolytic capacitor from a short circuit, the impedance characteristic of the capacitor is deteriorated due to the separator. In other words, the wound-type electrolytic capacitor, advantageous for increasing the capacitance, is inferior to the chip-type electrolytic capacitor in high-frequency characteristic.
As hereinabove described, the conductive polymer solid electrolytic capacitor generally has one of the two typical structures. However, it is difficult to obtain a high withstand voltage while maintaining a high-frequency characteristic without reducing the capacitance by increasing the thickness of a dielectric layer in either structure. In order to solve this problem, the inventors have already developed an electrolyte consisting of an ionic liquid and a conductive polymer (refer to pamphlet of International Patent Laying-Open No. 2005/012599). The inventors have found that an ionic liquid has an excellent function of anodizing a valve metal and can repair defects of an oxide film of aluminum, for example, for implementing an electrolytic capacitor exhibiting a high withstand voltage. However, a general ionic liquid, exhibiting excellent ionic conductivity, has no electronic conductivity. If a large quantity of ionic liquid is added in order to implement a capacitor exhibiting a high withstand voltage, therefore, the impedance characteristic of the capacitor is disadvantageously deteriorated. If the quantity of the ionic liquid is small, on the other hand, the withstand voltage is not improved although an excellent impedance characteristic is obtained in this case. In other words, it is extremely important for a solid electrolytic capacitor comprising an electrolyte consisting of an ionic liquid and a conductive polymer to attain both of an excellent withstand voltage characteristic and an excellent impedance characteristic, which are in trade-off relation.
On the other hand, a method of forming an electrolyte by previously impregnating an electrode foil with an ionic liquid and thereafter polymerizing a monomer for forming a conductive polymer is also disclosed (Japanese Patent Laying-Open No. 2006-24708). However, this document, describing that the capacitance and a capacitive impregnation ratio can be improved, gives no description as to implementability of an excellent withstand voltage characteristic.

Conductive polymer solid electrolytic capacitor


A dynamic word size processing system which determines for each instruction the number of cycles required by a data path to compute the result. Values in a register file are augmented with additional information which permits a determination of the number of cycles required based on the values in the register file which are referenced by each instruction. A control path combines the information for each register file operand, and computes a value for the additional information to be stored with the result of the instruction.

In order to reduce development costs of hardware and software of computer systems, it is highly desirable to specify a common architecture design among a series of designs. The common architecture specifies a user instruction set and other system facilities that several processor designs implement compatibly. The use of a common architecture allows the reuse of hardware and software designs across a number of distinct architecture designs that vary in performance, cost, memory capacity and other design parameters.
A scalable architecture is a series of hardware designs which allows for variance of the design parameters while simultaneously maintaining a common architecture. One of the design parameters which limits the degree to which an architecture is scalable is the word size of the instruction set.
The word size of the instruction set is the number of bits of width of operands in the operations specified by the instruction set. Most processors utilize a word size that is a power of two, such as 16, 32, 64, or even 128 bits. The word size of some instructions may be different than others. For example, a processor may have some instructions with a 16 bit word size and others that have a 32 bit word size, where the word size is decoded from the instruction code, such as the Motorola 68000.
The data path size is the number of bits of width of operands which are taken in parallel in a data path to perform the operations specified by the instruction set.
The data path size is generally equal to the maximum word size in many implementations. When the word size varies, such an implementation leaves a portion of the data path unused or useless computing a value which is not stored. However some designs, such as the Motorola 68000, which has a 32-bit word size, implement the processor with a 16-bit data path. Such a design requires multiple execution cycles to perform 32-bit word size instructions.
When the data path size is equal to the maximum word size, performance is optimized, but instructions which use less than the maximum word size are not performed with the best possible efficiency, because the circuits which are not employed in the computation consume power and circuit area. When the data path size is less than the maximum word size, less circuit area is used, and the performance and power is directly proportional to the word size. Consequently, the latter design has lower price and power, but lower performance.
When small two's complement values appear as operands or results in a processor with a wide word size, many of the high order bits of these operands will be identical to the sign bit. However, if successive values of operands or results change the sign of the value, many bits change value. These changing values can result in substantial use of power in CMOS or other implementation technologies that consume power primarily on signal transitions.
Thus, there exists a need for a method and apparatus for dynamically varying the word size of the data paths and various control paths in accordance with the size of the operands so as to eliminate the foregoing problems and increase overall efficiency and performance.

System and method for minimizing the size of operands


A frictional material is made of cloth which is impregnated with a bituminous material and/or a synthetic resin. The cloth is woven from a yarn made by twisting single yarns with reinforcing metal wires. The single yarn consists of a center core in the form of a roving or a yarn of inorganic fibers such as glass fiber, rock wool or ceramic fiber and a covering element in the form of a sliver of organic fibers such as staple fiber, aromatic polyamide fiber or flame-resistant fiber. The frictional material obtained is excellent in physical strength and in resistance against heat, effective for preventing dispersion of dust and irritation to human bodies, and advantageous from the viewpoint of cost.

1. Field of the Invention
This invention relates to an improvement of a woven type frictional material to be used as a winch of a marine machine or a construction machine, a brake lining or a disk pad of an automobile, and so on.
2. Description of the Prior Art
One of existing woven type frictional materials (using cloth as its basic element) is made by preparing cloth which is woven with one or a mixture of asbestos fiber, aramid fiber, glass fiber, rock wool, ceramic fiber, staple fiber, or the like, and by impregnating the cloth with a bituminous material or a synthetic resin such as asphalt, gilsonite, tung oil, etc.
The existing frictional material indicated above, however, involves the following problems because of a fiber or fibers used as the basic element of the cloth:
(1) Among the fibers indicated above, the asbestos fiber was considered to be an optimum frictional material because of its excellent resistance against heat and friction. However, the use thereof has been restricted because it adversely affects human bodies.
(2) The rock wool and the ceramic fiber are physically weak and, during handling, produce much dust which irritates human skin.
(3) The glass fiber is physically strong, but produces dust during handling, like the rock wool and the ceramic fiber.
(4) The staple fiber is not resistant against heat.
Since each of the fibers used as basic elements of existing frictional materials has advantages and disadvantages from different viewpoints, as indicated above, an improvement thereof is strongly desired.

Frictional material comprising bi-component yarn twisted with a metal wire


To provide a voltage division resistor for acceleration tube, an acceleration tube, and an accelerator capable of reducing the cost of the acceleration tube and enhancing the operation efficiency. An acceleration tube (1) for accelerating ions (charged particles) I by applying an acceleration voltage V comprises a tubular acceleration tube body (2) made of synthetic resin, a plurality of ring-like acceleration electrodes (3) arranged in a row on the inner circumferential surface (2a) of the acceleration tube body (2) at predetermined intervals in the axial direction of the acceleration tube body (2), a plurality of voltage division resistors (voltage division resistors for the acceleration tube) (5) wound spirally on the outer circumferential surface (2b) of the acceleration tube body (2), and a plurality of terminal bolts (terminal member) (4) provided in close contact with the acceleration tube body (2) while penetrating the acceleration tube body (2) radially and having a forward end (front end) (4a) connected electrically with the acceleration electrodes (3) and a head (rear end) (4b) connected electrically with each connector (connection point) (16) of the voltage division resistor (5).

As a conventional art of this kind, there has been known a multistage acceleration type charged particle beam generating apparatus in which two adjacent acceleration electrodes are electrically connected by a voltage division resistor for dividing an acceleration voltage applied at a time of accelerating the charged particle within the acceleration tube (for example, refer to patent document 1).
Patent Document 1: Japanese Unexamined Patent Publication No. HEI11-025900 (pages 3 and 4, FIG. 1 etc.)

Voltage division resistor for acceleration tubes, acceleration tube, and accelerator


In a general aspect, a method for producing a semiconductor device assembly can include defining a cavity in a conductive spacer, and electrically and thermally coupling a semiconductor die with the conductive spacer, such that the semiconductor die is at least partially embedded in the cavity. The semiconductor die can have a first surface having active circuitry included therein, a second surface opposite the first surface, and a plurality of side surfaces each extending between the first surface of the semiconductor die and the second surface of the semiconductor die. The method can also include electrically coupling a direct bonded metal (DBM) substrate with the first surface of the semiconductor die.

Semiconductor device assemblies, such as semiconductor device modules that include multiple semiconductor die (e.g., multi-chip modules) can include spacers (conductive spacers) that are coupled (e.g., electrically and/or thermally coupled) with the semiconductor die. Current approaches for implementing such spacers can have certain drawbacks. For example, mismatches in thermal expansion coefficients (CTEs) between various materials included in such assemblies can cause stress on the semiconductor die, which can result in cracks and/or damage to the semiconductor die. Further, voids in materials (e.g., adhesive materials, such as solder, conductive adhesives, etc.) used to couple the semiconductor die with the spacers can exacerbate CTE mismatch issues, as well as increase thermal resistance and/or electrical resistance between the spacer and the semiconductor die. Such increased thermal and/or electrical resistance can result in reliability issues due to heat generated within the semiconductor device assembly, and/or can adversely affect electrical performance of the semiconductor die and an associated semiconductor device module.

This patent is subject to a terminal disclaimer.

Assembly processes for semiconductor device assemblies including spacer with embedded semiconductor die

SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC


A sensor structure for chemochromic optical detection of hydrogen gas over a wide response range, that exhibits stability during repeated coloring/bleaching cycles upon exposure and removal of hydrogen gas, comprising: a glass substrate (20); a vanadium oxide layer (21) coated on the glass substrate; and a palladium layer (22) coated on the vanadium oxide layer.

The invention relates to an ultra-stable vanadium oxide thin film structure for the detection of hydrogen gas. The hydrogen gas is dissociated on the Pd catalyst into H atoms, and the V2O5 layer on which the Pd is coated functions as a H+ insertion host. The Pd layer is thus stabilized, which upon combination with hydrogen is chemochromically changed.
Hydrogen is a plentiful, clean, non-polluting fuel. Hydrogen is currently used in many industries, and the US demand for hydrogen is approximately 140 billion cubic feet per year and growing. However, hydrogen is explosive at 4% in air. Therefore, it is critical to measure, monitor and control hydrogen wherever it is used.
In the gas detection art where sensors and measurement instrumentation for hydrogen gases detect and/or measure hydrogen, typically there is required a portable sensing device, a kit (where hydrogen gas detection and/or measurement is required in existing equipment), and sensor heads installed at points where hydrogen leaks are possible, or where monitoring is necessary (i.e., in internal combustion engines which operate using hydrogen as a fuel).
The problems associated with current H2 detection devices is that these devices do not exhibit stable cycling during repeated coloring/bleaching processes and are encumbered by a narrow response range for detecting H2.


An electrode for an ignition device formed from a dilute nickel alloy with improved resistance to high temperature oxidation, sulfidation, corrosive wear, deformation and fracture. The electrode includes at least 90% by weight of nickel; zirconium; boron and at least one element from the group consisting of aluminum, magnesium, silicon, chromium, titanium and manganese. The weight ratio of Zr/B may range from about 0.5 to 150, and may include amounts of, by weight of the alloy, 0.05-0.5% zirconium and 0.001-0.01% boron. The oxidation resistance may be improved by the addition of hafnium in an amount that is comparable to the amount of zirconium, which may include an amount of, by weight of the alloy, 0.005-0.2% hafnium. Electrodes of dilute nickel alloys which include aluminum and silicon, as well as those which include chromium, silicon, manganese and titanium, are particularly useful as spark plug electrodes.

1. Field of the Invention
The invention relates to a high performance electrode made from a dilute nickel alloy containing alloying additions of zirconium and boron that is temperature, oxidation, sulfidation and fracture resistant and, more particularly, toward an electrode for an ignition device, such as a spark plug for an internal combustion engine, furnace, or the like.
2. Related Art
A spark plug is a spark ignition device that extends into the combustion chamber of an internal combustion engine and produces a spark to ignite a mixture of air and fuel. Recent developments in engine technology are resulting in higher operating temperatures to achieve improved engine efficiency. These higher operating temperatures, however, are pushing the spark plug electrodes to the very limits of their material capabilities. Presently, Ni-based nickel-iron-chromium alloys specified under UNS N06600, such as those sold under the trade names Inconel 600®, Nicrofer 7615®, and Ferrochronin 600®, as well as various dilute nickel alloys, are in widespread use as spark plug electrode materials. Dilute nickel alloys are high nickel alloys, having nickel contents that are generally greater than 90% by weight of the alloy, with small amounts of varying alloying elements, such as silicon, aluminum, yttrium, chromium, titanium, cobalt, tungsten, molybdenum, niobium, vanadium, copper, calcium, manganese and the like, to improve the high temperature properties over that of pure nickel, including enhanced resistance to high temperature oxidation, sulfidation and associated corrosive wear, as well as deformation, cracking and fracture associated with cyclic thermo-mechanical stresses resulting from operation of these devices.
As is well known, the resistance to high temperature oxidation of these dilute nickel alloys decreases as their operating temperature increases. Since combustion environments are highly oxidizing, corrosive wear including deformation and fracture caused by high temperature oxidation and sulfidation can result and is particularly exacerbated at the highest operating temperatures. At the upper limits of operating temperature (e.g., 1400° F.), tensile, creep rupture and fatigue strength also have been observed to decrease significantly which can result in deformation, cracking and fracture of the electrodes. Depending on the electrode design, specific operating conditions and other factors, these high temperature phenomena may contribute individually and collectively to undesirable growth of the spark plug gap and diminished performance of the ignition device and associated engine. In extreme cases, failure of the electrode, ignition device and associated engine can result from electrode deformation and fracture resulting from these high temperature phenomena. These failure modes and effects can be particularly problematic in competitive applications, such as racing engines.
Accordingly, there is a need for high performance electrodes made from dilute nickel alloys having improved resistance to high temperature oxidation, sulfidation and related corrosive wear, as well as improved high temperature tensile, creep rupture and fatigue strength and resistance to cracking and fracture.


A stereomicroscope has a left and a right stereo radiation path and adjusting means for selecting a stereo base. The main lens is arranged between an object to be observed and the adjusting means, which are preferably designed as opto-mechanical switching means. This arrangement allows an integrated structure with low light losses to be obtained.

The invention relates to a stereomicroscope.
Stereomicroscopes having a capability for adjusting the stereo base are described in U.S. Pat. No. 3,818,125 (Butterfield, 1971). Although different variations of possibilities for varying the stereo base are described there, such devices have not become widespread in practice. This is in spite of the fact that the disadvantages which are known and specified by Butterfield in the case of stereomicroscopes without stereo base adjustment are still present. To this extent, reference is made to the relevant description parts--in particular in column 2, lines 43-62--in Butterfield, which count as disclosed herein. The reason for not using the teachings of Butterfield apparently lies in various problems which result from his solution proposals. Thus, for example, the use of prisms is excluded (e.g. FIGS. 5-9 in Butterfield), since, as Butterfield himself admits (column 9, lines 65 and 66 of Butterfield), these are accompanied by color aberrations which can have a negative influence on the color quality of the viewed image.
The variations proposed by Butterfield having displaceable aperture diaphragms (10, e.g. FIGS. 2 and 5) furthermore have the disadvantage that as a result of a displacement of the latter not only is the stereo base adjusted but in addition the image brightness is darkened or changed, which can disadvantageously lead to too low a light yield, in particular in the case of small stereo bases.
Similar disadvantages occur in the case of the solution proposal in accordance with FIG. 10 of Butterfield. To be specific, as a result of the pivoting of the mirror (50), not only is the stereo base adjusted, but the aperture is also changed, which in turn can lead to corresponding light losses.
The variants proposed by Butterfield according to FIGS. 11 and 12 are in turn complicated and can be implemented only with difficulty to the extent that two parallel lens systems (54) are necessary there, which are associated with a corresponding increase in price and also a corresponding increase in constructional size, with further penalties in terms of light as a result of possibly too small an aperture. Furthermore, it is generally also difficult to adjust such parallel lens systems such that they have identical properties. However, if the properties are not identical, this can lead to fatigue in the observer, in particular if a video camera and monitor are connected in front of said observer, since he does not have the possibility of recorrecting individually, as in the case of two eyepiece beam paths.
It is therefore an object of the present invention to develop a system which, in spite of a variable stereo base, does not reduce the light intensity in the beam path--at least for a certain period and for each beam path separately--by a significant amount. In addition, it is intended to enable recordings--as known per se--using only a single image recording device, for example using a single video camera. Preferably, it is furthermore intended to provide only one main objective and to restrict the constructional size of the stereomicroscope to a minimum.
This object is achieved, for example, by means of the features described herein. As a result of the arrangement of the adjusting device behind the main objective, there is an integrated construction with low light losses and without the disadvantages listed above.
A practical application of the invention results, for example, in the case of video stereomicroscopes.
For such microscopes, but also for other microscopes, a special development of the invention is proposed which can also be applied independently of the invention. To explain the background:
Microscopes often have beam splitters in order to duplicate the beam path directed towards the object to be magnified.
Often provided on split beam paths are, inter alia, additional observer eyepieces, phototubes, camera connections or displays of all types, the images from which are intended to be inserted--that is to say superimposed on the image of the viewed object. This applies in particular also to stereomicroscopes which have an image recording device for producing a stereo view on a 3D display--possibly remote from the microscope.
For the last application, from time to time such an image recording device (e.g. a CCD each) is provided both for the beam path assigned to the left eye and also for the beam path assigned to the right eye.
For the application having the inserted display, in an analogous manner a display (e.g. a CRT each) is provided for the beam path assigned to the left and also to the right eye.
These known stereomicroscopes thus have the disadvantage that two magnification devices (zoom, turret) and two image recording devices or two displays, together with appropriate optics, are necessary. In this case, the left and right image recording devices or optics must be mutually adjusted.
In other known stereomicroscopes there are also solutions having only a single image recording device.
There, both the left and the right beam path or the ray bundle located in them are alternately fed to the single image recording device. As a result of such a construction, a second image recording device is saved and, inter alia, the serial recording of a stereoimage pair on one video recording device is facilitated. The changeover process between the two beam paths is in this case achieved using beam splitters and shutters which block off the respective undesired bundle of rays via polarization changes using correspondingly arranged analyzers.
Such a stereomicroscope having geometric superimposition of the right and left frames is described, for example, in U.S. Pat. No. 5,007,715.
The system which is described in U.S. Pat. No. 5,007,715 has the disadvantage that, both during the polarization (about 50%) and during the superimposition (about 50%) of the two polarized bundles of rays by means of a beam splitter, up to 80% of the light intensity which is present of the respective bundles of rays (100%) are lost. A partial superimposition of the two different sets of image information from the right and left image beam paths can make itself noticeable as a further disadvantage if the darkening by the analyzers is not 100%, which can primarily also occur if the polarizers do not operate satisfactorily. Since however it is precisely in microscopes that the brightness on the object to be viewed cannot be arbitrarily increased, the permanent loss in light intensity is disadvantageous. The partial superimposition, on the other hand, can lead to unnecessary stresses for the organs of sight of the observer.
A similar known system is described in U.S. Pat. No. 5,003,385, where likewise about 80% of the light intensity of the left and right beam paths are absorbed before the light is incident on the single camera.
A somewhat different system, where the polarization of the light remains unconsidered, is described in U.S. Pat. No. 5,028,994. There, the light from two first beam paths (left and right beam path) is firstly fed in each case to an LC shutter (twisted nematic type), which can open or close the relevant beam path. The two beam paths are incident--deflected via mirrors--on a beam splitter. If one shutter is open, then the second shutter is closed, for which reason theoretically it is always only possible for light from one of the two first beam paths to arrive at the camera arranged downstream of the beam splitter. At the beam splitter, in each case about 50% of the light intensity is lost; likewise at the shutter, even in the "open condition", about 50% in each case is lost, since the described shutter structure (cf. column 2 line 48 to column 3 line 29) permit only light of a specific polarization direction to pass through. In addition, in the case of the described shutter, the abovementioned disadvantages of partial superimposition may also occur.


A given DSP, when processing signals of a channel, stores channel instance data in a multiplexed memory in association with itself. If the channel processing task changes to one for which the given DSP is not optimised, the given DSP moves the channel to an appropriate new DSP. Additionally, the given DSP transfers the association of the channel instance data to an association with the new DSP. In this way, the new DSP is provided with the channel instance data without the requirement for physically transferring such data.

This invention relates to a method and system for processing digital communication channels.
Digital channels in a communications system are typically processed for a number of purposes. For example, a voice channel in a digital communications system may require processing for echo canceling, dual tone multi-frequency (DTMF) decoding, and audio decoding, Digital signal processors (DSPs) are used to accomplish such processing. A DSP may store software algorithms enabling it to perform one or more channel processing tasks. This optimises the DSP to perform these channel processing tasks. (The term "optimise" is a common spelling variant of the term "optimize" with identical meaning.) Further, a DSP may be able to simultaneously handle processing for several channels. To cope with an ever increasing number of processing tasks and an ever increasing number of charnels to be processed, many DSP chips now include multiple DSP processing centers, known in the art as DSP cores, coordinated by a host processor.
While a DSP is processing a channel, the required channel processing task for the channel may change. By way of example, a DSP may be decoding an audio channel which had been compressed (i.e., encoded) to 64 kB/s in accordance with ITU recommendation G.711. However, while doing so, it may be that the bit rate of the channel drops to 16 kB/s in view of the level of compression dropping to that according to ITU recommendation G.728. Such a change could occur in response to a drop in the quality of service for the channel. Given a change in the processing requirements for a channel, in some instances the DSP may be able to dynamically switch to new software to handle the new processing task. For example, in U.S. Pat. No. 6,108,343 to Cruickshank et al. program code for several tasks may have been downloaded from slow memory to the DSP program memory. In such case, if the channel processing task changes to another task for which the DSP memory has the necessary program code, the DSP may quickly switch to the new software. However, the limited capacity of the DSP memory restricts the number of programs which may be held therein. Thus, there will be situations where a DSP cannot be readily provisioned for the new channel processing task.
Therefore, there remains a need for a system which can effectively respond to changes in the processing task for a channel.

Instance memory handoff in multi-processor systems


An architecture to avoid handover ping-pong for aerial user equipment (UE) operational in terrestrial fourth generation (4G) and/or fifth generation (5G) long term evolution (LTE) networks. A method can comprise receiving a request to connect to the network equipment from aerial user equipment; based on the request to connect, retrieving subscription data; based on the subscription data, determining that the aerial user equipment is aerial equipment; determining that the aerial user equipment is engaged in a ping-pong handover event with terrestrial based network equipment situated within a defined geographic area; and transmitting instructions to the aerial user equipment to confirm the ping-pong handover event, wherein the instruction comprises a delay value representing a back off time value for the aerial user equipment to refrain from gathering measurement data within the defined geographic area.

The ping-pong handover issue for aerial user equipment (UE) can be caused by the sending and receiving of frequent measurement reports, which typically are not required at cell edge regions of wired and/or wireless communication networks. In instances where aerial user equipment is flying at high altitude and is in a edge section between serving cell equipment and strong neighbor cell network equipment, ping-pong handover can occur as a consequence of the unnecessary sending and/or receiving of measurement reports. In the context of ping-pong handover, ping-pong handover events are more likely to occur with respect to aerial user equipment rather than in regard to terrestrial based user equipment, because aerial user equipment, at altitude, generally has better line of sight (LOS) to ground based networking equipment, such as serving cell equipment and/or neighbor cell network equipment; altitude effectively magnifies the cell edge coverage area of neighbor cell network equipment.

Handover for aerial user equipment served by terrestrial networks


A power converter is provided. The power converter includes a heat sink provided with a holding unit, a plurality of semiconductor devices disposed on the heat sink, and a fixing assembly pressing each of the semiconductor devices toward the heat sink to fix the semiconductor device. The fixing assembly includes a lower push unit disposed on the semiconductor device, and an upper push unit disposed on the lower push unit to press the lower push unit downward, the upper push unit being coupled to the holding unit. The upper push unit includes a central bent part that partially protrudes downward, an insertion part disposed on each of both ends of the central bent part in a left/right direction, the insertion part having a left/right distance therebetween that gradually increases upward, and a fixing bar inserted into the insertion part.

The present disclosure relates to a power converter, and particularly, to a power converter to which a semiconductor device is easily coupled.
Power converters means devices that convert certain power into power that is different in current, voltage, frequency, and so on.
Recently, each of most power converters includes a printed circuit board (PCB) and a plurality of semiconductor devices mounted on the PCB.
FIG. 1 is a schematic view of a power converter according to a related art.
Referring to FIG. 1, in a power converter according to a related art, a coupling hole 20A is defined in a heat sink 20 fixed to a printed circuit board (PCB) 10, and a fixing hole 30a is defined in an upper portion of a semiconductor device for power to match the coupling hole 20A, thereby fixing the semiconductor device 30 for power to the heat sink 20 by coupling a screw 40.
However, such the semiconductor device for power has a fixing structure in which the semiconductor device for power is fixed to and separated from the heat sink by manually tightening and releasing the screw one by one when the semiconductor device for power is coupled to the heat sink. As a result, the attachment/detachment of the semiconductor device for power may be cumbersome and inconvenient, and thus productivity may be deteriorated.
Since the PCB and the semiconductor device are coupled to each other by using a bolt after being soldered, torsion may occur in the semiconductor device while the PCB and the semiconductor device are coupled to each other by using the bolt. Therefore, the power converter may be deteriorated in durability.


An improved two-stage process for the preparation of polyester resins is provided which involves an initial reaction of a dicarboxylic acid such as isophthalic acid with an alkylene oxide such as ethylene or propylene oxide in the presence of a catalyst to form an oligoester reaction mixture, followed by a second stage reaction between the oligoester reaction mixture and a dibasic acid or anhydride; a first-stage catalyst is employed which has a thermal decomposition temperature substantially at or below the second-stage reaction temperature. The most preferred first-stage catalyst is benzyltriethylammonium chloride.

1. Field of the Invention
The present invention is broadly concerned with an improved two-step process for the preparation of polyesters wherein use is made of a first-stage catalyst having a relatively low decomposition temperature allowing substantially complete thermal decomposition of the catalyst prior to the second-stage reaction. More particularly, the invention pertains to such an improved process involving an initial catalyzed reaction between a carboxylic acid (e.g., isophthalic acid or terephthalic acid) and an alkylene oxide (e.g., propylene or ethylene oxide) in the presence of a low-degradation temperature catalyst such as benzyltriethylammonium chloride in order to form an oligoester mixture; in preferred practice, the reaction product is heated to essentially completely decompose the first-stage catalyst, whereupon the oligoester reaction product is reacted with a dibasic acid or anhydride. Advantageously, the first-stage catalyst has a thermal degradation temperature at or below the second-stage reaction temperature.
2. Description of the Prior Art
A well-known route for the production of polyester resins involves an initial reaction between a carboxylic acid and an alkylene oxide in the presence of a catalyst to form an oligoester (typically hydroxyalkyl ester) reaction product. This first-stage addition reaction is generally carried out at an elevated temperature on the order of 100.degree.-230.degree. C. and at a superatmospheric pressure of up to about 15 kg/cm.sup.2. A variety of catalysts have been proposed for use in this context, such as simple amines (U.S. Pat. No. 4,306,056) and alkyl quaternary amine compounds (U.S. Pat. No. 4,560,788).
After the first-stage reaction is completed, it is conventional to heat the reaction mixture in the presence of an inert gas such as nitrogen in order to remove the first stage catalyst. At this point, the catalyst-stripped first-stage reaction product may be mixed with a glycol such as dipropylene glycol and the mixture is reacted with a diacid or anhydride, especially maleic anhydride at elevated temperatures and pressures. This yields the desired unsaturated polyester product.
A significant problem with prior two-stage processes for polyester resin production stems from the fact that residual first-stage catalysts remaining in the second-stage reaction mixture tends to significantly discolor the final polyester resin products. Moreover, the attempted thermal degradation of the first-stage catalysts represents a material energy input to the process, thus raising costs.
There is accordingly a real and unsatisfied need in the art for an improved two-stage polyester resin process which ameliorates the problems of resin discoloration and excess energy usage.

Polyester synthesis using catalysts having low decomposition temperatures


A system for testing a software client or hardware module in a voice-over-IP (VoIP) network path includes a VoIP client, a test tool, and an analyzer. The VoIP client, connected to the VoIP network, makes a series of calls to a destination. The calls activate the software client or hardware module under test. The test tool, which has access to the network, plays a series of audio files over the VoIP during the calls. The test tool also polls the software client or hardware module over the network for status information after the calls are completed. While the audio files are being played, the analyzer records the audio files at the destination for measurement the quality of the calls. Accordingly, the quality of voice connection on the VoIP network can be measured, and specific components on the network can be tested.

Voice-over-IP (VoIP) is a technique for delivering voice information over a network that employs the Internet Protocol (IP). The network, called a VoIP network, transmits voice information digitally in the form of voice packets. The VoIP network is different from a public-switched telephone network (PSTN), which transmits voice signals as a stream of analog signals. Protocols used by the PSTN generally include IXC (Interchange Carrier), LEC (Local Exchange Carrier), and C-LEC (Competitive Local Exchange Carrier), which transmit analog voice signals in a manner different from the IP.
Although a VoIP network is different from a PSTN in many aspects, a phone call that originates from a PSTN can be sent over the VoIP network to a computer. Conversely, voice packets originating from the Internet can also be sent over the VoIP to reach a telephone on a PSTN. For example, an Internet Telephony Service Provider (ITSP) network is a VoIP network. The ITSP network is built on the physical infrastructure of the Internet, and further includes gateways to perform appropriate conversions for transmitting calls between a PSTN and the Internet. The gateway includes conversion circuits for performing analog-to-digital and digital-to-analog conversions, as well as appropriate protocol conversions.
For voice packets received from the Internet, the gateway converts them into analog signals, and sends the analog signals to the PSTN. The gateway also converts analog signals coming from the PSTN into voice packets. The gateway performs the conversions in both directions at the same time, allowing a full-duplex (two-way) conversation to take place between users connected to either the Internet or the PSTN.
Compared to transmissions of data packets, voice transmissions are more susceptible to delays and variations in the delays. The delay variations, also called jitters, can greatly distort voice signals and render them unrecognizable to a user. Therefore, maintaining a Quality of Service (QoS) acceptable to a user is an important issue in voice transmissions. Furthermore, because the IP is a "best effort" protocol that generally does not guarantee QoS, there is no assurance of the quality of voice transmissions over a VoIP network. Some VoIP networks therefore use an improved version of the IP, called Real-Time Protocol (RTP), to transmit voice packets to ensure QoS and timely delivery of the voice packets. RTP provides end-to-end delivery services of real-time audio and video.
Quality of voice transmissions can be determined using conventional measurements for data transmissions, such as distortions, packet loss, and signal-to-noise ratio. However, characteristics of voice transmissions are different from those of data transmissions in many aspects. One of the most distinctive aspects of voice transmissions is the subjectivity of voice quality. Standards have been developed to measure the quality of voice transmissions from the perspective of a listener. The standards include Perceptual Speech Quality Measurement (PSQM) and Perceptual Analysis-Measurement System (PAMS).
PSQM is an ITU standard that defines an algorithm for estimating the subjective quality of voice-band speech codecs (coder-decoder). PSQM is an advanced version of MOS (Mean Opinion Score) algorithm, which has been widely used as a subjective means to rate vocoders (voice coder). Scores produced by the PSQM algorithm range from a scale of 1 (ideal) to 5 (poor). The PSQM scores can be converted to MOS scores by a standard formula.
The PSQM algorithm measures distortions of a speech signal when transmitted through various codecs and transmission media. It can effectively measure voice quality on IP networks and wireless networks. Unlike measurement of signal-to-noise ratios, the PSQM algorithm measures distortions in an internal psycho-acoustic domain to mimic the sound perception of people (e.g., phone users) in real-life situations, so that the measured distortions can be correlated with human perceptions. The PSQM algorithm converts signals in a physical domain into the perceptually meaningful psycho-acoustic domain through a series of nonlinear processes. The processes generally include time-frequency mapping, frequency warping, intensity warping, loudness scaling, asymmetric masking, cognitive modeling, and so forth.
Another important standard for measuring clarity of voice signals as perceived by a human is Perceptual Analysis-Measurement System (PAMS). The PAMS uses a perceptual model similar to that of PSQM to provide a repeatable, objective means for measuring perceived voice quality. The PAMS uses an effective signal processing model to produce a number of types of scores. The PAMS provides a "listening-quality" and a "listening-effort" score, both of which can be converted to MOS scores and are on the same 1-to-5 scale.
Voice quality on an IP network can be determined using the above standards together with the conventional measurements for data transmissions. Deterioration of voice quality is often an indicator of a problem in the network. Frequently, the problem in the network is in a hardware module or a software client along a transmission path of the voice signals.

QOS testing of a hardware device or a software client


A user-friendly, network-connected learning thermostat is described. The thermostat is made up of (1) a wall-mountable backplate that includes a low-power consuming microcontroller used for activities such as polling sensors and switching on and off the HVAC functions, and (2) separable head unit that includes a higher-power consuming microprocessor, color LCD backlit display, user input devices, and wireless communications modules. The thermostat also includes a rechargeable battery and power-stealing circuitry adapted to harvest power from HVAC triggering circuits. By maintaining the microprocessor in a “sleep” state often compared to the lower-power microcontroller, high-power consuming activities, such as learning computations, wireless network communications and interfacing with a user, can be temporarily performed by the microprocessor even though the activities use energy at a greater rate than is available from the power stealing circuitry.

While substantial effort and attention continues toward the development of newer and more sustainable energy supplies, the conservation of energy by increased energy efficiency remains crucial to the world's energy future. According to an October 2010 report from the U.S. Department of Energy, heating and cooling account for 56% of the energy use in a typical U.S. home, making it the largest energy expense for most homes. Along with improvements in the physical plant associated with home heating and cooling (e.g., improved insulation, higher efficiency furnaces), substantial increases in energy efficiency can be achieved by better control and regulation of home heating and cooling equipment. By activating heating, ventilation, and air conditioning (HVAC) equipment for judiciously selected time intervals and carefully chosen operating levels, substantial energy can be saved while at the same time keeping the living space suitably comfortable for its occupants.
Historically, however, most known HVAC thermostatic control systems have tended to fall into one of two opposing categories, neither of which is believed be optimal in most practical home environments. In a first category are many simple, non-programmable home thermostats, each typically consisting of a single mechanical or electrical dial for setting a desired temperature and a single HEAT-FAN-OFF-AC switch. While being easy to use for even the most unsophisticated occupant, any energy-saving control activity, such as adjusting the nighttime temperature or turning off all heating/cooling just before departing the home, must be performed manually by the user. As such, substantial energy-saving opportunities are often missed for all but the most vigilant users. Moreover, more advanced energy-saving settings are not provided, such as the ability to specify a custom temperature swing, i.e., the difference between the desired set temperature and actual current temperature (such as 1 to 3 degrees) required to trigger turn-on of the heating/cooling unit.
In a second category, on the other hand, are many programmable thermostats, which have become more prevalent in recent years in view of Energy Star (US) and TCO (Europe) standards, and which have progressed considerably in the number of different settings for an HVAC system that can be individually manipulated. Unfortunately, however, users are often intimidated by a dizzying array of switches and controls laid out in various configurations on the face of the thermostat or behind a panel door on the thermostat, and seldom adjust the manufacturer defaults to optimize their own energy usage. Thus, even though the installed programmable thermostats in a large number of homes are technologically capable of operating the HVAC equipment with energy-saving profiles, it is often the case that only the one-size-fits-all manufacturer default profiles are ever implemented in a large number of homes. Indeed, in an unfortunately large number of cases, a home user may permanently operate the unit in a "temporary" or "hold" mode, manually manipulating the displayed set temperature as if the unit were a simple, non-programmable thermostat.
At a more general level, because of the fact that human beings must inevitably be involved, there is a tension that arises between (i) the amount of energy-saving sophistication that can be offered by an HVAC control system, and (ii) the extent to which that energy-saving sophistication can be put to practical, everyday use in a large number of homes. Similar issues arise in the context of multi-unit apartment buildings, hotels, retail stores, office buildings, industrial buildings, and more generally any living space or work space having one or more HVAC systems. Other issues arise as would be apparent to one skilled in the art upon reading the present disclosure.
It is to be appreciated that although exemplary embodiments are presented herein for the particular context of HVAC system control, there are a wide variety of other resource usage contexts for which the embodiments are readily applicable including, but not limited to, water usage, air usage, the usage of other natural resources, and the usage of other (i.e., non-HVAC-related) forms of energy, as would be apparent to the skilled artisan in view of the present disclosure. Therefore, such application of the embodiments in such other resource usage contexts is not outside the scope of the present teachings.
Provided according to some embodiments is programmable device, such a thermostat, for controlling an HVAC system. The programmable device includes high-power consuming circuitry adapted and programmed to perform while in an active state a plurality of high power activities including interfacing with a user, the high-power consuming circuitry using substantially less power while in an inactive state or sleep state. The device also includes low-power consuming circuitry adapted and programmed to perform a plurality of low power activities, including for example causing the high-power circuitry to transition from the inactive to active states; polling sensors such as temperature and occupancy sensors; and switching on or off an HVAC functions. The device also includes power stealing circuitry adapted to harvest power from an HVAC triggering circuit for turning on and off an HVAC system function; and a power storage medium, such as a rechargeable battery, adapted to store power harvested by the power stealing circuitry for use by at least the high-power consuming circuitry such that the high-power consuming circuitry can temporarily operate in an active state while using energy at a greater rate than can be safely harvested by the power stealing circuitry without inadvertently switching the HVAC function. Examples of the high power activities includes wireless communication; driving display circuitry; displaying a graphical information to a user; and performing calculations relating to learning.
According to some embodiments, the high-power consuming circuitry includes a microprocessor and is located on a head unit, and the low-power consuming circuitry includes a microcontroller and is located on a backplate.

User-friendly, network connected learning thermostat and related systems and methods


A writing instrument that includes a barrel extending along a longitudinal axis (A) and a tip mounted at the front of the barrel, further including a protective sleeve for the tip, the sleeve being mounted coaxially on the barrel and movable relative to the barrel between a protective position where it covers the tip and a retracted position where it exposes the tip to allow writing. The sleeve includes an inner wall which includes a helical cam engaging with a guide element formed on the barrel so that the sleeve is movable in translation combined with rotation.

Field of the Invention
The embodiments of the present invention relate to a writing instrument comprising a barrel extending along a longitudinal axis and a tip mounted at the front of the barrel, further comprising a protective sleeve for the tip, said sleeve being mounted coaxially on the barrel and movable in translation relative to the barrel between a protective position where it covers the tip and a retracted position where it exposes the tip to allow writing, said sleeve having an inner wall which comprises a helical cam engaging with a guide element formed on the barrel so that the sleeve is movable in translation combined with rotation, said sleeve further comprising on its inner wall a detent element capable of engaging with a retaining element formed on the barrel so as to prevent the sleeve from being detached from the barrel.
Description of Related Art
Such a writing instrument is known from U.S. Pat. No. 2,941,511. The barrel comprises a guide element formed by a screw thread, and the guiding helical cam on the inner wall of the sleeve is formed by a helical groove which engages the thread. The retaining element of the barrel is formed by an annular collar of frustoconical shape, and the detent element of the sleeve is formed by an annular flange projecting inwardly at the rear end of the inner wall of the sleeve. The annular collar has an outside diameter slightly greater than the inside diameter of the annular flange, and the sleeve has a resilience adapted so that the inside diameter of the annular flange can increase to allow passing over the annular collar when force fitting the sleeve onto the barrel. In the tip protection position, the helical groove of the sleeve is disengaged from the screw thread of the barrel, so that an inner shoulder of the sleeve abuts against the thread and prevents the sleeve from retracting when pressed upon. The sleeve can then rotate freely without causing a translational movement, but a position is necessarily provided where the screw thread again engages with the helical groove to allow screwing the sleeve onto the barrel.
This known writing instrument offers the advantage of a reliable guide for the movement of the sleeve on the barrel, because of the conventional solution of a screw thread engaged in a helical groove. As these elements are designed to be inflexible and rigid enough not to deform, there is virtually no risk that the thread will come out of the groove, particularly in the case where the user continues to exert a screwing force on the sleeve when it is in the retracted position, or in other words when the tip is exposed. In comparison, other known writing instruments with movable protective sleeves use at least one guide element consisting of a radially flexible element engaged in a helical slot that is closed at both ends. There is then a risk that because of its flexibility, a guide element comes out of the slot when excessive force is exerted on the sleeve, which detaches the protective sleeve from the barrel. Another advantage of the writing instrument known from U.S. Pat. No. 2,941,511 is that it does not require a through-slot in the wall of the sleeve, which can be advantageous for example if creating a molded grip on the outer surface of the sleeve.
This writing instrument has various drawbacks, however. In particular, in the tip protection position, the sleeve is not securely locked because it can rotate freely which allows accidental engagement of the screw thread with the helical groove and consequently screwing the sleeve on the barrel. This phenomenon can occur when the instrument is stored in a pocket and subjected to random stresses. Accidental retraction of the sleeve could result in stained clothing since the tip is no longer protected. Furthermore, as the sleeve is not rotationally locked when in the tip protection position, it does not feel sturdy to the user. In addition, intentionally screwing the sleeve from its protective position takes time, since the user must first gently rotate the sleeve to a position where the thread engages with the groove.
The invention aims in particular to resolve the above drawbacks, by providing a firm and reliable locking of the sleeve in the tip protection position, while guiding the movement of the sleeve on the barrel with no risk of the guide element disengaging from the helical cam and while not requiring a through-slot in the sleeve wall.
To this end, the embodiments of the present invention relates to a writing instrument as defined above, characterized in that it comprises a locking element capable of engaging with one among said retaining element and said detent element so as to lock said protective position.
With these arrangements, the protective position is locked so that the sleeve is immobilized in translation and in rotation relative to the barrel, with no risk of accidentally leaving its position. Furthermore, since the locking element engages one among the retaining element and detent element which between them snap-fit the sleeve on the barrel during mounting, this implies that the retaining element or detent element provides both a sleeve snap-fitting function and a sleeve locking function in the protective position. It is thus not necessary to provide a specific element distinct from the retaining element and detent element to cooperate with the locking element, which simplifies the molding of the sleeve or barrel.
In preferred embodiments of a writing instrument according to the embodiments of the present invention, use is made of one or more of the following arrangements, possibly in combination:
The locking element is formed on the inner wall of the sleeve, preferably in the immediate vicinity of the detent element, and is capable of engaging with the retaining element;
The locking element is formed on the barrel, preferably in the immediate vicinity of the retaining element, and is capable of engaging with the detent element;
the detent element extends in a circumferential direction of the sleeve, forming a detent tooth having an apex as well as a first face and a second face arranged on each side of said apex, said first face extending locally substantially perpendicular to a cylindrical surface of the inner wall of the sleeve and forming a detent tooth stop which engages with the retaining element in said protective position; thereby facilitating the snap-fitting of the sleeve onto the barrel, allowing an elastic deformation of the sleeve in the radial direction which is primarily localized to the detent tooth and in addition allows irreversible latching without compromising the ease of assembly, unlike the device known from U.S. Pat. No. 2,941,511 in which the sleeve must be radially deformed along its entire circumference in order to be snap-fitted onto the barrel;
the retaining element extends in a circumferential direction of the barrel, forming a retaining tooth which has an apex as well as a first face and a second face, arranged on each side of said apex, said first side extending locally substantially perpendicular to an outer cylindrical surface of the barrel and forming an abutment that engages with said detent tooth stop in said protective position; whereby the snap fit is more securely irreversible;
the guide element of the barrel is formed by a helical rib extending circumferentially relative to the barrel axis over an angle of less than 170°, and the helical cam of the sleeve comprises a helical groove with which said helical rib engages; thereby facilitating the molding of the guide element integral with the barrel;
said angle over which the helical rib extends circumferentially is between 60° and 120°, and said helical rib forms with the barrel axis a pitch angle of between 20° and 50°; thereby allowing a rotation of the sleeve of less than a half-turn and preferably about a quarter-turn to be sufficient to move the sleeve from the protective position to the retracted position, thus facilitating manipulation by the user;
the retaining element has an angular position with respect to the barrel axis that is substantially opposite the average angular position of the guide element, and has an axial position that is offset towards the rear of the barrel with respect to said guide element;
the inner wall of the sleeve comprises a first wall portion in which is formed at least a portion of the helical cam and generally having a first diameter, and comprises a second wall portion generally having a second diameter larger than said first diameter; which is advantageous for providing a sufficiently high guide element for the strength of the guide, as well as a sleeve of relatively small diameter while having a wall that is generally fairly thick to ensure the overall stiffness of the sleeve;
the locking element s formed on said second wall portion immediately adjacent to the detent element; thereby facilitating the local radial deformation of the sleeve at the detent element and locking element and so facilitating engagement with the retaining element; the guide element and retaining element are formed on a front portion of the barrel forming a generally cylindrical tube having an outside diameter substantially equal to said first diameter, and the guide element has an outer radius substantially equal to half said second diameter; which is advantageous for ensuring proper axial alignment of the sleeve with the barrel;
a second locking element is formed by a second protuberance placed on said second wall portion and arranged to lock the retracted position of the sleeve; thereby preventing the sleeve from leaving the retracted position while the user is writing;
each of said first and second protuberances have a cylindrical shape that is truncated in its axial direction, said axial direction being parallel to the longitudinal axis of the sleeve; thereby facilitating unmolding of the sleeve during manufacture.
The writing instrument represented in FIG. 1 and FIG. 2 has a barrel 1 which extends along a longitudinal axis A. The barrel 1 comprises a front portion 1A generally forming a cylindrical tube, and a main cylindrical tubular portion 1B of larger outside diameter than the front portion 1A, which form an annular shoulder 1E where they join. A protective sleeve 2, visible in detail in FIGS. 7 to 10, is mounted to allow its helical movement on the front portion 1A of the barrel, coaxially to the barrel 1. The sleeve 2 is movable between a protective position (FIG. 1) where it covers a writing tip 7 in order to protect it, and a retracted position (FIG. 2) where it exposes the tip 7 to enable writing.
In its refracted position, the sleeve 2 abuts against the annular shoulder 1E of the barrel. Advantageously, the sleeve 2 has a rear end edge 2E forming a flat surface which comes in full contact with the annular shoulder 1E which also forms a flat surface. In addition, the sleeve 2 has an outside diameter equal to that of the main portion 1B of the barrel. In this manner, in the retracted position of the sleeve, the sleeve and barrel form a continuous surface with no gaps where they meet, which is esthetically advantageous and enables the user to hold the instrument comfortably while writing.
In an embodiment of the writing instrument according to the invention which is not represented, a grip may be overmolded onto the outer surface of the sleeve 2. This grip can also cover the flat surface of the rear end edge 2E of the sleeve 2, and thus come into contact with the annular shoulder 1E of the barrel in the retracted position of the sleeve 2.
As represented in FIGS. 3 to 6, in a first embodiment of the writing instrument of FIG. 1, the front portion 1A of the barrel 1 has an outside diameter D1A smaller than the outside diameter of the main portion 1B of the barrel (FIG. 5), and on its outer surface comprises a guide element 10 and a retaining element 11. The guide element 10 is formed by a helical rib extending circumferentially relative to the longitudinal axis A of the barrel over an angle α, for example about 90°, between a front end 10F and a rear end 10R of the rib (FIG. 6).
Advantageously, the angle α is less than 170°, which facilitates molding the outer surface of the barrel 1 with a mold comprising two half-molds, the helical rib 10 then being formed by one half-mold. Even more preferably, the angle α is between 60° and 120°. The helical rib 10 forms with the longitudinal axis A of the barrel a pitch angle β of between 20° and 50° (FIG. 3), so that rotation of the sleeve 2, for example by about 90°, is sufficient to move the sleeve along its entire translational path between the protective position and the retracted position. This arrangement facilitates manipulation by the user, because the transition of the sleeve from one position to the other can be achieved with one quick motion.
The retaining element 11 extends in a circumferential direction of the barrel 1 to form a retaining tooth 11C having an apex 11C as well as a first face 11A and a second face 11B arranged on each side of the apex (FIG. 6). The first face 11A forms a steep side of the tooth, and preferably extends locally substantially perpendicular to an outer cylindrical surface of the front portion 1A of the barrel from which the tooth protrudes. "Locally extends perpendicular to a cylindrical surface" is understood to mean a direction perpendicular to a plane which is tangent to the cylindrical surface, at the local area in question.
For example, the first face 11A extends in a radial plane of said outer cylindrical surface, meaning a plane containing the longitudinal axis A of the barrel, which is the case in the embodiment represented. However, the plane of the extension of the first face 11A is not necessarily radial, and in one embodiment (not shown) the plane may have a certain inclination with respect to the longitudinal axis A of the barrel while remaining substantially perpendicular locally to said outer cylindrical surface of the barrel.
Advantageously, the retaining tooth 11 is positioned relative to the longitudinal axis A in an angular position substantially opposite the average angular position of the helical rib 10, as can be seen in FIG. 6, and has an axial position that is offset towards the rear of the barrel with respect to the rib 10, as can be seen in FIG. 5 where the axial offset is represented by the distance L1.
In addition, the retaining tooth 11 is positioned at a distance L2 from the annular shoulder 1E of the barrel, said distance L2 preferably being equal to the translational travel of the sleeve 2 between the protective position and the retracted position. The helical rib 10 has an outer radius R10. Advantageously, the retaining tooth 11 has the same height as the rib 10, meaning that its apex lies on a circle of radius R10 (FIG. 6).
As represented in FIGS. 7 to 9, in the first embodiment of the writing instrument of FIG. 1, the protective sleeve 2 has an inner wall 2I which comprises a helical cam 20. This helical cam comprises in particular a helical groove 20A formed in a first wall portion 8 of the inner wall 2I of the sleeve (FIG. 9, FIG. 10). The helical rib 10 of the barrel is adapted to engage with the helical groove 20A, so that translation of the sleeve is combined with rotation of the sleeve.
The sleeve 2 further comprises a detent element 21 on its inner wall 2I, adapted to pass over a retaining element 11 of the barrel and thus snap-fit the sleeve onto the barrel during assembly to prevent the sleeve from separating from the barrel.
The passage of the two elements over one another is possible due to the capacity of the sleeve for a certain elastic deformation in the radial direction. The plastic material used for the sleeve, and the structure and thickness of the sleeve walls, are parameters to be taken into account to achieve sufficient elastic deformation of the sleeve for the desired snap-fit.
Advantageously, the detent element 21 extends in a circumferential direction of the sleeve 2, forming a detent tooth. With this arrangement, when the detent tooth 21 passes over the retaining tooth 11 of the barrel during assembly, the elastic deformation of the sleeve in the radial direction is mainly localized at the detent tooth, which facilitates the snap-on assembly of the sleeve onto the barrel. Even more preferably, the detent tooth 21 has an apex 21C as well as a first face 21A and a second face 21B arranged on each side of the apex. The first face 21A forms a steep side of the tooth, and preferably extends locally substantially perpendicular to a cylindrical surface of the inner wall 2I of the sleeve.
This first face 21A forms a stop for the detent tooth 21 which, in the protective position of the sleeve, cooperates with the abutment formed by the first face 11A of the retaining element 11 For example, the first face 21A extends in a radial plane of said cylindrical surface of the inner wall 2I, meaning a plane containing the longitudinal axis of the sleeve, which is the case in the embodiment represented. However, the plane of the extension of the first face 21A is not necessarily radial, and in one embodiment (not shown) the plane may have a certain inclination with respect to the longitudinal axis. The second face 11B of the retaining tooth 11 and the second face 21B of the detent tooth do not form steep sides of the teeth, but sides that slope for example at an angle of less than 45° locally with respect to a cylindrical surface of the front portion 1A of the barrel or of the inner wall of the sleeve. In this manner, the second face 21B of the detent tooth 21 is designed to exert pressure on the second face 11B of the retaining tooth 11 during assembly in order to radially deform the sleeve and/or barrel, until the detent tooth 21 passes beyond the retaining tooth 11 to snap-fit the sleeve 2 on the barrel 1 in the protective position of the sleeve, as explained below with reference to FIG. 12 and FIG. 13.
The first wall portion 8 of the inner wall 2I of the sleeve, in which the groove 20A is formed, generally has a first diameter D1 more or less equal to the outside diameter D1A of the front portion 1A of the barrel 1, so that the sleeve 2 can slide coaxially on the front portion 1A of the barrel. Considering manufacturing tolerances, in practice it is arranged so that D1 is slightly greater than D1A. The inner wall 2I of the sleeve comprises a second wall portion 9 generally having a second diameter D2 greater than the first diameter D1 (FIG. 9). This second wall portion 9 serves in particular to position the helical rib 10 of the barrel in the sleeve 2 during assembly, since the second diameter D2 is slightly greater than twice the outside radius R10 of the helical rib 10. In addition, the smaller radial thickness of this wall portion 9 serves to provide areas of the sleeve that facilitate elastic deformation in the radial direction. A first locking element 22 is formed on the second wall portion 9 of the sleeve and is located immediately adjacent to the detent element 21, provided for cooperating with the retaining element 11 so as to lock the protective position. The locking in position can be more or less strong, to prevent accidental retraction of the sleeve 2 but without making it difficult for the user to complete the sleeve screwing motion and expose the tip 7. It is understood that the shape and height of the first locking element 22 affect the strength of the locking in the protective position.
The first locking element 22 is, for example, formed by a first protuberance having a cylindrical shape truncated in its axial direction, for example a half-cylinder shape. The axial direction of the protuberance is parallel to the longitudinal axis A of the sleeve. The rounded form of the protuberance is advantageous so that the protuberance can pass over the retaining element 11 of the barrel in both directions of rotation of the sleeve 2 and without excessive resistance. The first protuberance 22 is arranged to come in contact with the second face 11B of the retaining tooth 11 in the protective position of the sleeve, as is particularly visible in FIG. 13. In this manner, the locking of the sleeve in the protective position can be relatively strong, meaning that screwing the sleeve from its protective position requires an initial screwing force sufficient to elastically deform the sleeve and/or barrel so that the first protuberance 22 passes over the retaining element 11.
Advantageously, a second locking element 23 is formed by a second protuberance arranged on the second wall portion 9 of the sleeve so as to lock the sleeve in the retracted position. The second protuberance 23 has, for example, a truncated cylindrical shape similar to that of the first protuberance 22, so as to cooperate in a similar manner with the retaining element 11. This cylindrical shape similarly extends advantageously in an axial direction parallel to the longitudinal axis of the sleeve. These arrangements facilitate molding the sleeve during manufacture. It is understood that the two protuberances 22 and 23 and the detent tooth 21 may be formed using a single central spindle which is removed along the longitudinal axis of the sleeve during unmolding. The second protuberance 23 is located towards the front of the sleeve relative to the first protuberance 22, on the helical path that the retaining element 11 follows relative to the wall portion 9 of the sleeve.
Other solutions for locking the sleeve in the retracted position are possible without providing such a second protuberance 23. For example, the first protuberance 22 could be extended axially slightly beyond the rear end edge 2E of the sleeve, to form a projection adapted to cooperate with a corresponding detent notch formed on the barrel at the annular shoulder 1E of the barrel.
The first wall portion 8 and the second wall portion 9 of the sleeve join by forming a rectilinear shoulder area 24 which extends parallel to the longitudinal axis A of the sleeve, as well as a helical shoulder area 20B located in the extension of the helical groove 20A and which forms a ramp portion of the helical cam 20. The helical shoulder area 20B is arranged so as to position the helical rib 10 which comes in contact with said area 20B in a mounting position of the sleeve (FIG. 11), such that the front end 10F of the helical rib is facing an entrance 20AB to the helical groove 20A (FIG. 10). The rectilinear shoulder area 24 also serves to guide the front end 10F of the helical rib to the entrance 20AB to the groove.
Advantageously, the second face 21B of the detent tooth 21 is joined at its base to an end portion 9E of the second wall portion 9 of the sleeve (FIG. 7). This arrangement improves the elastic deformation of the sleeve 2 at the detent tooth 21, which therefore facilitates snap-fitting the sleeve on the barrel during assembly. As represented in FIG. 11, where the sleeve is in the mounting position, the retaining element 11 of the barrel is arranged to be positioned substantially in the same angular position as the end portion 9E of said aforementioned second wall portion 9. As mentioned above, the helical rib 10 is then in contact with the ramp portion 20B of the helical cam 20 and is ready to be engaged with the helical groove 20A. In this manner, pressure exerted on the front of the sleeve 2 causes the front 10F of the helical rib 10 to engage with the entrance 20AB to the helical groove 20A, which initially causes the sleeve to screw onto the barrel with virtually no resistance until the detent element 21 comes in contact with the retaining element 11. Greater effort is then needed to snap the sleeve onto the barrel, or in other words for the detent element 21 to pass beyond the retaining element 11 and bring the sleeve into its protective position as shown in FIG. 12 and FIG. 13.
It is especially apparent in FIG. 13 that the steep side of the detent tooth 21, meaning the first face 21A visible in FIG. 8, forms a detent stop which cooperates with the steep side of the retaining tooth 11 to make the locking of the sleeve on the barrel irreversible. Indeed, the first faces of the two teeth each extend in a radial plane of the sleeve, said plane containing the longitudinal axis A of the barrel. Mutual pressure between the first faces of the teeth therefore produces stresses exerted only in the circumferential direction of the sleeve, which does not cause any radial deformation of the sleeve. As a result, there is no risk of the user separating the sleeve from the barrel when unscrewing the sleeve to protect the tip. The unscrewing force required to break the detent would not be achievable during normal use of the writing instrument.
As is particularly visible in FIG. 13, the locking element 22 being in the immediate vicinity of the detent element 21 allows the retaining tooth 11 to be in contact with each of the aforementioned elements 21 and 22 in the protective position of the sleeve, avoiding play during movement to help stabilize the protective position. Furthermore, as shown in FIG. 12 and in FIG. 13, the retaining tooth 11 has a rear face to provide surface continuity with the flat rear end edge 2E of the sleeve 2 in the protective position of the sleeve, which is particularly advantageous in terms of aesthetics.
In the protective position of the sleeve, the helical rib 10 is partially engaged in the helical groove 20A. If the user rotates the sleeve 2, for example in the conventional screwing-in direction for the embodiment shown and with sufficient force for the first locking element 22 to pass beyond the retaining tooth 11, the sleeve advances towards the barrel until the second locking element 23 comes in contact with the sloped side of the retaining tooth 11, meaning the second face of the tooth, where the user will feel some resistance to screwing. The rear end edge 2E of the sleeve is then very close to the annular shoulder 1E of the barrel. Continuing the screwing motion with sufficient force allows the second locking element 23 to pass beyond the retaining tooth 11, which can be arranged to coincide with the rear end edge 2E of the sleeve coming in contact with the annular shoulder 1E of the barrel. As represented in FIG. 14, the sleeve is then in its retracted position. Advantageously, the second locking element 23 remains in contact with the retaining tooth 11 in order to reinforce the stability of the retracted position. The strength of the locking in this position is such that the position cannot be unlocked when the user writes with normal pressure on the writing tip 7. In effect, if the user writes while holding the instrument only by the sleeve 2, the retracted position of the sleeve can become unlocked if pressure exceeding that of normal use is exerted on the tip. This unlocking causes a relative displacement of the tip to enter the sleeve.
As represented in FIG. 15, in the embodiment of the writing instrument described in the foregoing, the writing tip 7 is fixedly mounted at the front of a reservoir tube of ink 3 held stationary in the barrel 1. In particular, the reservoir tube 3 is mounted in abutment against a conical end portion of the front portion 1A of the barrel. Advantageously, a rear cap 5 is screw-mounted at the rear of the barrel, and a supporting spacer 4 is mounted in the barrel between the rear cap 5 and the rear of the reservoir tube 3 to keep the tube stationary. Replacement of the cartridge formed by the reservoir tube 3 and tip 7 is possible by taking off the rear cap 5 and removing the support spacer 4.
In a second embodiment with reference to FIGS. 16 to 19, the locking element is formed on the barrel and not on the sleeve. As represented in FIG. 17 and FIG. 18, the locking element may be formed by a protuberance 12 located in the immediate vicinity of a tooth 11 constituting the retaining element. In this second embodiment, barrel 1′ differs from barrel 1 described above with reference to FIGS. 3 to 6 solely in the addition of the protuberance 12.
Advantageously, the locking protuberance 12 has a generally rounded shape, for example semi-cylindrical. It is positioned facing the steep side of the retaining tooth 11 in the circumferential direction, and its height is preferably less than the height of the tooth 11. In this manner, the protuberance 12 is able to pass beyond the detent element 21 of the sleeve 2′ represented in FIG. 16, in both directions of rotation of the sleeve, unlike the retaining tooth 11 which in the same manner as in the first embodiment cannot pass back over the detent element 21 once assembled.
The locking protuberance 12 cooperates with the detent tooth 21 to lock the protective position as represented in FIG. 25 19. In this position, the detent tooth 21 is arranged between the retaining tooth 11 and the locking protuberance 12 and preferably remains in contact with these projecting elements 11 and 12 to stabilize the position. To unlock the protective position, the user must initiate rotation of the sleeve with sufficient force for the locking protuberance 12 to pass beyond the detent tooth 21. It is understood from the foregoing that the locking protuberance 12 is functionally equivalent to the first locking protuberance 22 in the first embodiment, and therefore fulfills an identical locking function in the same protective position of the sleeve.
Therefore, a first locking element 22 is not necessarily useful in the protective sleeve 2′ of the second embodiment. As represented in FIG. 16, the sleeve 2′ comprises a single locking protuberance 23, for example identical to the second locking element 23 of the first embodiment, so as to lock the sleeve in the retracted position. In this retracted position, it can be arranged so that locking protuberance 23 is held between the retaining tooth 11 and locking protuberance 12. In the embodiment shown, sleeve 2′ differs from sleeve 2 described above with reference to FIGS. 7 to 10 only in the elimination of the first locking element 22.
However, it is understood that sleeve 2′ may be identical to the previously described sleeve 2, meaning that it can keep the first locking element 22, without incompatibility with the second embodiment described above. This variant of the aforementioned second embodiment of the invention can be useful when wanting to further reinforce the locking of the sleeve in the protective position. Indeed, from the representation in FIG. 19, it is understood that the addition of a locking protuberance 22 as can be seen in FIG. 13 has the effect of increasing the user effort required to rotate the sleeve so that not only does the locking protuberance 12 formed on the barrel pass over the detent tooth 21 formed on the sleeve, but also the locking protuberance 22 formed on the sleeve passes over the retaining tooth 11 formed on the barrel.
The two locking protuberances 12 and 22 may advantageously be designed to avoid or nearly avoid contact with each other during movement of the sleeve between its protective position and retracted position. For example, the height of each locking protuberance 12 or 22 in the radial direction may be less than or equal to half the height of the tooth 11 in the radial direction. In this manner, one protuberance 12 or 22 does not travel over the other protuberance 12 or 22 during rotation of the sleeve, or only barely touches the other, which generates no additional resistance corresponding to the pressing of protuberance 12 on protuberance 22. A user turning the sleeve to lock it in the protective position only perceives one point of resistance to be overcome before completing the rotation to lock the sleeve.
In one embodiment (not represented) of the writing instrument of the invention, compatible with all embodiments described herein, a fixed writing tip may be provided that can withdraw slightly towards the inside of the barrel during writing, by means of a damping device which for example allows a small movement of the cartridge within the barrel under the effect of the pressure exerted on the tip. The damping device may, for example, be implemented as a spring mounted between a movable supporting spacer and the rear cap 5.
The foregoing describes a retaining element 11 and a locking element 21 that are formed by teeth which are not inherently flexible radially, meaning that the latching action of these teeth is made possible by local elastic deformation, in the radial direction, of the wall of the sleeve and/or barrel at a tooth. Additionally or alternatively, it is possible to provide that at least one of these teeth is inherently elastically deformable radially, in order to reduce radial deformation stresses on the sleeve and/or barrel during assembly.
For example, a recess can be molded during manufacture, in the form of a notch in the circumferential direction at the base of the steep side of a tooth, so that the tooth forms a flexible tab having a certain elasticity in the radial direction. It is also possible, for example, to provide longitudinal slits in the wall of the front portion of the barrel on either side of the retaining element 11, to obtain greater flexibility of the wall locally at this element.
The invention also relates to a kit for creating the writing instrument of the invention, said kit comprising the barrel (1) and the protective sleeve (2) to be mounted on the barrel, wherein the inner wall (2I) of the sleeve comprises a first wall portion (8) in which is formed at least a portion (20A) of the helical cam (20) and generally having a first diameter (D1), and comprises a second wall portion (9) generally having a second diameter (D2) larger than the first diameter (D1), the guide element (10) of the barrel being arranged facing said second wall portion (9) in a mounting position where the sleeve is engaged on the barrel and ready to be snapped into place thereon.
In preferred embodiments of a kit according to the invention, use is made of one or more of the following arrangements, possibly taken in combination:
the guide element (10) of the barrel is formed by a helical rib, the helical cam (20) of the sleeve comprises a helical groove with which said helical rib engages, said first and second wall portions (8, 9) join to form at least one shoulder area (20B) constituting a ramp portion of the helical cam with which the helical rib comes in contact, such that a front end (10F) of the helical rib is facing an entrance (20AB) to said helical groove in said mounting position of the sleeve; the sleeve is therefore already guided as it moves on the barrel before snapping into place, which facilitates the snap-fitting;
the helical cam (20) of the sleeve engages with the guide element (10) of the barrel to obtain a helical movement of the sleeve relative to the barrel between said mounting position and the protective position of the sleeve;
the retaining element (11) of the barrel and the detent element (21) of the sleeve exert a pressure on one another adapted to deform in a radial direction at least one among the barrel and sleeve between said mounting position and the protective position of the sleeve, so as to snap-fit the sleeve onto the barrel.

Writing instrument having a movable protective sleeve