A composition suitable for forming a sidewall for a tire includes a rubber composition which includes at least one rubber, an ethylene/propylene/diene terpolymer, and a polyalkylene copolymer. The rubber may include one or more natural or synthetic rubbers, such as butadiene rubbers and isoprene rubbers. The ethylene/propylene/diene terpolymer preferably has an ethylene content of at least 60%. The polyalkylene copolymer may be a copolymer of a polyalkylene and an α-olefin, which is formed in a polymerization reaction involving a single site catalyst. The polyalkylene copolymer preferably has a high degree of crystallinity, being preferably at least about 90% by weight ethylene, with a melting point in the range of 80° C.–120° C. The presence of such a copolymer in the rubber composition markedly increases the resistance to crack growth and formation of cracks in the tire sidewall.

1. Field of the Invention
The invention relates to a composition. In particular, it relates to a composition comprising an ethylene/propylene/diene terpolymer and a crystalline ethylene/olefin copolymer, which is suited for forming a tire sidewall, and will be described with particular reference thereto. It will be appreciated, however, that the composition has a variety of other uses, in particular, where ozone and crack resistance are sought.
2. Discussion of the Art
Rubber tires, such as pneumatic tires, include sidewalls and treads, among other components. Because of the different conditions to which these components are subjected, the composition of the sidewall is generally different from that of the tread. Sidewalls are continuously subjected to distortion under normal road operating conditions. The extensive flexing can cause the sidewalls to crack. In addition to flex cracking, sidewalls are also subjected to atmospheric chemical action such as ozone attack. The overall result is that the sidewalls are prone to erosion and degradation.
The addition of amorphous ethylene/propylene/diene (EPDM) rubber for various tire components, such as a sidewall component is known to reduce the need for antioxidants and antiozonants in the composition, primarily because of its superior resistance to ozone degradation. This results in an improved sidewall appearance. However, a disadvantage of EPDM elastomers is that they tend to have poor crack growth resistance and poor adhesion.
Various methods of improving crack growth resistance have been proposed, including the addition of precipitated silica in the presence of a silica coupling agent such as, for example, an organosilane polysulfide which contains at least about 3.5 sulfur atoms in its polysulfidic bridge (See U.S. Pat. No. 6,279,633). Addition of halobutyl rubber has been suggested to improve crack growth resistance, as disclosed, for example, in U.S. Pat. Nos. 4,224,196, 5,532,312, and 6,201,049).
The present invention provides a new and improved tire wall composition and method of preparation.

Composition containing ethylene/propylene/diene copolymer and polyalkylene/olefin copolymer


A tubing coupling method is provided. In one aspect, the method comprises providing a length of expandable tubing and a length of larger diameter non-expanding tubing, connecting an end portion of the expandable tubing to an end portion of the non-expanding tubing, running the tubing into a bore, and expanding the expandable tubing. The expandable tubing may form part of an expandable well or sand screen, or may be an expandable bore liner.

1. Field of the Invention
This invention relates to expandable downhole tubing. In particular, the invention relates to coupling or connecting expandable downhole tubing. One aspect of the invention relates to a method of locating a section of expandable tubing in a bore.
2. Description of the Related Art
Expandable tubing for use in downhole applications is useful as, for example, borehole liner or as a sandscreen support. In one application, a section of expandable tubing is positioned in an unlined section of bore intersecting a hydrocarbon-bearing formation, below an existing bore casing and bore liner. The tubing is then expanded, preferably into contact with the bore wall. The expanded liner supports the bore wall while allowing oil and gas to pass from the formation into the bore. In another application, an expandable well screen is provided, the screen comprising perforated filter sheets mounted on an expandable slotted carrier tube and within a coaxial expandable slotted protective tube. The well screen is expanded downhole to such a size that the protective tube can be set against the surrounding formation.
For locating expandable tubing in a bore it would be preferable to provide a secure connection between the upper end of the expandable tubing and the lower end of an existing bore liner; simply locating the tubing in the liner, with no mechanical connection therebetween, may result in an offset between the two, creating an irregularity on which tools may snag and an unwanted gap through which fluid may flow.
U.S. Pat. No. 3,353,599 discloses a method for securing ends of expandable liner to solid surrounding tubing by means of plastic impregnated glass filter mats. However, the applicant considers that this method would encounter many difficulties in this particular application due to, for example, contamination of the mats by the fluid in the bore and the possibility of the mats being dislodged or damaged during installation of the liner and the expandable tubing, or during other downhole operations.

This patent is subject to a terminal disclaimer.

Methods of placing expandable downhole tubing in a wellbore


Systems and computer program products may perform unattended software installation. The systems and computer program products may include receiving a user's selection of one or more software installation files, and reading at least a portion of the one or more user-selected software installation files. The systems and computer program products may additionally include extracting, from the read one or more software installation files, questions that a user will be asked to answer during execution of the one or more user-selected software installation files, and compiling the extracted questions. The systems and computer program products may further include prompting a user to provide answers to the compiled questions, and receiving answers to one or more questions of the compiled questions prior to execution of the one or more user-selected software installation files. The systems and computer program products may additionally include storing the received answers, and providing the stored answers when requested during execution of the one or more user-selected software installation files.

The present inventions generally relate to software installation technologies, and more specifically, to installation systems that prompt the user for input during the installation process.
Installing software on a computer system may involve running an installation program, such as a script. The installation program may obtain information about the computer receiving the installation, the preferences of the user conducting the installation, and/or other values or variables by prompting the user for input. For example, a program that updates a browser software package may generate a dialog box during the installation process to ask the user whether to import bookmarks from a prior browser. The program may pause the installation process while waiting for the user to respond. A program that intermittently seeks inputs from the user may force the user to actively attend to the installation process, which may become a time-consuming chore.

Performing unattended software installation

International Business Machines Corporation


A pointing device is provided which can reduce its size and height, reduce leakage magnetic flux density to the outside. Magnetic sensors are disposed symmetrically two by two on X and Y axes on a printed circuit board. A silicone resin is placed on the printed circuit board, and an internally and externally unipolarly magnetized ring-like magnet is placed near the center of the magnetic sensors. The printed circuit board and silicone resin are not bonded. The silicone resin is easily deformed by applying external force, and returns to its initial state without the external force as soon as the external force is removed. The ring-like magnet is configured to move approximately in parallel to the surface of the printed circuit board. The variations in the ambient magnetic flux density produced by the movement of the ring-like magnet are detected by the magnetic sensors.

FIG. 1 is a block diagram showing a magnetic detector circuit of a conventional magnetic detection type pointing device. A detecting section 1 includes four magnetic sensors (such as Hall elements, semiconductor magneto-resistive elements, thin-film magneto-resistive elements and GMR elements) 11, and the Hall elements 11 are placed symmetrically two by two on the X and Y axes. A magnet is placed near the center of the four Hall elements 11 symmetrically disposed on the X and Y axes. Because of the variations in the magnetic flux density due to the movement of the magnet, the output voltages of the Hall elements 11 vary.
Differential amplifiers 2 differentially amplify the outputs of the Hall elements 11 on the X and Y axes, respectively. The output is adjusted to zero when the magnetic flux density in the Z direction is symmetry with respect to the origin O, that is, when the magnetized direction of the magnet is in the vertical direction. As the magnet moves, the differential amplifiers 2 produce outputs, and a detection control section 3 converts the outputs (analog values) in the X coordinate value and Y coordinate value, which are output through an output control section 4.
As a concrete example of a small pointing device used by a mobile phone, a device is known which employs a scheme placing a magnet on a key mat. Such devices based on the method enable miniaturization among the currently proposed ideas (see Japanese patent application laid-open No. 2002-150904, for example).
As a contact type pointing device, a device is common which forms on a printed board two pairs of comb electrodes, and depresses them via a conductive rubber from the top to vary the current-passing state, thereby outputting coordinate values in digital values.
However, in small mobile electronic equipment such as a mobile phone, further reductions in size and height of the components are required to satisfy mutually contradictory needs of reducing the size and improving the function of the electronic equipment in its entirety. In addition, further improvement in operating feelings of the magnetic detection type pointing device is expected.
Furthermore, as for the foregoing publication, since the magnet is magnetized in the vertical direction, the magnetic flux density that leaks out is large so that when a magnetic card is brought close to it, a problem of losing the information of the magnetic card is likely to occur.
Moreover, since the input is made by depressing the conductive rubber in the contact type pointing device, degradation of the conductive rubber involved in repetitive input and the like is unavoidable, which presents a problem of reducing the life.
The present invention is implemented to solve the foregoing problems. Therefore it is an object of the present invention to provide a pointing device that can reduce the size and height, and provide a good operating feeling, and that has small external leakage of the magnetic flux density, and has a long product life.


An agricultural sweep has an upwardly extending stem adapted to be secured to a tine of an agricultural implement and a ground breaking member comprised of a pair of substantially planar wings diverging rearwardly from a tip. In order to prevent bending or breaking of the sweep, a reinforcing ridge is provided at the juncture of the wings and the stem, the ridge extending along a longitudinal axis of the sweep from the upper surface of the wings to a point on the stem between the base and the upper end of the stem.

Agricultural sweeps are employed as tools in cultivating soil. They typically comprise a stem portion by which they are removably mounted on the lower end of a tine of an agricultural tillage implement, and an earthworking portion attached to the stem which is pulled through the soil to eliminate weeds. The earthworking portion typically has an arrowhead shape and comprises a pair of symmetrical wing elements extending rearwardly from a point. As a result of their use, sweeps are subject to wear and considerable stress, and are particularly prone to bending or breaking at the transition between the stem and the earthworking portion.
This problem has received only cursory consideration in the prior art. For example, Canadian Patent No. 1,189,380 describes an agricultural sweep in which strength is provided at the transition between the stem and the earthworking portion by maintaining the gauge of the metal at the transition and by providing stem side walls which extend continuously through the transition region and form downwardly turned flanges at the upper, trailing edges of the wings.
However, it is desirable that the junction of the stem and the wings be further strengthened in order to further reduce the incidence of bending or breakage at the transition between the stem and earthworking portion of the sweep. Such strengthening would extend the life of individual sweeps, maintain proper sweep angle to thereby reduce energy consumption, and permit the use of wider sweeps to thereby reduce the number of sweeps which must be mounted on the implement.

Agricultural sweep having reinforcing ridge


Ultrafine dimensions, smaller than conventional lithographic capabilities, are formed employing an efficient inverse spacer technique comprising selectively removing spacers. Embodiments include forming a first mask pattern over a target layer, forming a spacer layer on the upper and side surfaces of the first mask pattern leaving intermediate spaces, depositing a material in the intermediate spacers leaving the spacer layer exposed, selectively removing the spacer layer to form a second mask pattern having openings exposing the target layer, and etching the target layer through the second mask pattern.

The relentless reduction in the dimensions of semiconductor device features into the deep sub-micron range challenges current fabrication techniques in several respects. It becomes increasingly more difficult to form such ultrafine critical design features with high dimensional accuracy. This problem becomes particularly acute in forming negative features, such as contact holes, via holes, trenches, and microcavities. The minimum size of a feature depends upon the chemical and optical limits of a particular lithography system, and the tolerance for distortions of the shape, such as corner rounding when forming negative features in a layer or substrate. Conventional approaches have included ablation of pattern photoresist, or definition of an inverse pattern to create a hard mask, on which the feature size can be further reduced by means of spacer lithography. These techniques have not proven completely successful or efficient.
Double exposure techniques and spacer lithographic processes have evolved. However, these techniques have not proven completely successful and suffer from low manufacturing throughput, some techniques requiring the repeated use of several tools and chemical mechanical polishing techniques. The competitive marketplace requires a very high throughput, such as yields of 70% and greater, to maintain a profit margin.
Accordingly, a need exists for methodology enabling the fabrication of semiconductor chips comprising devices having accurately formed features in the deep sub-micron range, such as features with a critical dimension less than 20 nm. There exists a particular need for such methodology enabling the accurate formation of ultrafine design features with high efficiency and high manufacturing throughput.


Described is a mechanism for issuing an event notification message, from a first program to a second program, to indicate that an action occurred within the first program, where the event notification message includes a parameter that indicates that the action is one of a group of possible actions. More specifically, in an application configured to edit documents created with the eXtensible Markup Language XML, the occurrence of an XML-related action causes the event notification message to be issued. The XML-related action may be either an XML-related move action, an XML-related insert action, or an XML-related delete action. In this way, a single event notification message can be used to indicate the occurrence of three different types of actions while editing an XML document.

Software applications are gradually becoming more and more complex and powerful. What was once a simple text editor may now be a complex word processor with countless rich features, for example the ability to create Web pages or edit XML markup. As technology evolves, each software application provides more and more functionality to enhance a user's experience. In addition, many software applications now expose their native functionality to add-on applications through programmatic interfaces. For example, object oriented programming has enabled some software applications and their documents to be treated as objects. These objects publicly expose the functionality of the applications in the form of methods that may be called and properties that may be read or set to manipulate the applications or documents. These advancements have enabled programmers to develop third-party add-ons to automate tasks and functions formerly performed manually while interacting with the application. Many such add-on applications are developed in simple programming languages, such as the Visual Basic for Applications (VBA) language. These add-ons can work by calling the application's methods and properties to achieve various goals and customize the application's core functionality for a custom environment.
In addition to being able to make calls from the custom code of the add-on to the core application, there is need for the custom code to be written in such a way that it actually responds to (as opposed to "initiates") calls from the application when something happens in the application itself. For example, one could want to write custom code for a word processing application, that reacts in some special way to the user's keystrokes received by the application and perhaps blocks some of them if the user is editing an area where only some types of letters are allowed. In such cases, there is need for a way for the programmer to let the application know that there is special custom code that the application should run when a given type of event occurs. Once the custom code is registered with the application, the code can now "react" in useful ways to specific events occurring within the core application, thereby extending the application's core functionality.

System and method for issuing a message to a program


A semiconductor package providing with a printed circuit board and a semiconductor device, including a semiconductor substrate having a surface provided with an external connection electrode and mounted on the printed circuit board, and, a surface opposite that with said external connection electrode, abrased with a mirror finish and reinforced with a back-surface reinforcement.

1. Field of the Invention
The present invention relates generally to semiconductor devices and particularly to semiconductor devices that can be packaged with enhanced anti-bendability.
2. Description of the Background Art
In recent years, semiconductor devices have been further reduced in size and further increased in density to meet a demand for smaller and lighter mobile phones, mobile information equipment and other similar electronics and electronic equipment. To meet this demand there has been proposed bare-chip packaging, a technique applied in mounting an LSI chip directly on a printed circuit board.
Reference will now be made to FIGS. 5A and 5B to describe bare-chip packaging. As a bare chip, an LSI chip 7 has thereon an electrode on which ball-bonding is for example employed to provide a metal bump 14 thereon to serve as an external connection electrode. With reference to FIG. 5A, with metal bump 14 aligned with an electrode 10 provided on a printed circuit board 9 to be packaged, LSI chip 7 is packaged on printed circuit board 9 facedown. FIG. 5B shows a complete packaging.
The market for mobile equipment such as mobile phones and PHSs has significantly expanded. As such, technological innovation has been promoted therefor and bare-chip packaging has thus been increasingly adopted. Conventionally, a package is impaired in reliability generally when temperature cycle causes thermal stress and thermal distortion resulting in defects. In addition, mobile equipment carried by a user can disadvantageously bend when it receives external force. Furthermore, disadvantageous bending stress can instantly occur when mobile equipment is dropped. Furthermore, in a process for manufacturing such mobile equipment, bending stress can occur in a printed circuit board while components are packaged. As such, it is also an important condition that mobile equipment have a mechanically reliable structure impervious to bending stress and the like.
Herein, the semiconductor device shown in FIGS. 5A and 5B has main components with their respective Young's moduli, as follows:
LSI chip (Si): approximately 12 to 14×1010 N/m2
Printed circuit board: approximately 0.5 to 2.5×1010 N/m2 and it can be understood that LSI chip 7 is formed of a material hard to bend as compared with the printed circuit board. As such, when force is exerted on printed circuit board 9 to bend it, LSI chip 7 does not accordingly bends. Thus, stress concentrates at a solder connection connecting printed circuit board 9 and LSI chip 7 together and when the limit of the stress has been reached the solder connection disadvantageously breaks and thus disconnects.
The present invention therefore contemplates a semiconductor device capable of alleviating such a disadvantage as described above when the entirety of a printed circuit board receives force exerted to bend it, and a method of manufacturing the same.

Semiconductor device having reinforcement member and method of manufacturing the same


A method of operation of a display system includes: receiving a recap request for a source media; generating source content descriptors for the source media with a control unit; extracting a source recap segment from the source media based on correlation of the source content descriptors with a recap theme associated with the recap request; and generating a custom recap with the source recap segment for displaying on a device.

Modern consumer and industrial electronics, especially devices such as graphical display systems, televisions, projectors, cellular phones, portable digital assistants, and combination devices, are providing increasing levels of functionality to support modern life including media processing. Research and development in the existing technologies can take a myriad of different directions.
The increasing demand for information in modern life requires users to access information at any time, while a variety of consumer devices allow for increased functionalities. However, increasing demand for information and media access "on demand" has been limited even though the consumer devices allow for increased functionalities.
Thus, a need still remains for display system with media processing to display "on demand" media. In view of the ever-increasing commercial competitive pressures, along with growing consumer expectations and the diminishing opportunities for meaningful product differentiation in the marketplace, it is increasingly critical that answers be found to these problems. Additionally, the need to reduce costs, improve efficiencies and performance, and meet competitive pressures adds an even greater urgency to the critical necessity for finding answers to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.

Display system with media processing mechanism and method of operation thereof


A receiver includes a tuning circuit for picking up a reception signal having a desired frequency, a local oscillator for forming an oscillation signal, a first mixer for frequency-converting the reception signal into an IF signal by using the oscillation signal, an IF filter for deriving the IF signal from an output signal of the first mixer, a signal forming circuit for forming an AC signal having a frequency equal to a frequency of the IF signal, a second mixer to be supplied with the AC signal and the oscillation signal, a deriving circuit for deriving a signal having a desired frequency or an image frequency from an output of the second mixer, and a detector for detecting a level of the IF signal, wherein a self test is performed by supplying the signal derived from the deriving circuit to the tuning circuit and checking a detection output level of the detector.

1. Field of the Invention
The present invention relates to a receiver of a super-heterodyne system.
2. Description of Related Art
In a receiver of a super-heterodyne system, the reception characteristics such as a reception sensitivity and image interference characteristics are degraded if the rated frequency relation between a reception frequency, a local oscillation frequency and an intermediate frequency is shifted.
A test signal generator is therefore provided for checking and adjusting the reception sensitivity, the center frequencies of an antenna tuning circuit and an intermediate frequency filter, and the reception characteristics such as image interference characteristics. A receiver is known which has therein a test signal generator of this type to provide a self test function. As prior art documents, refer to, for example, Japanese Laid-open Patent Applications No. 2000-13336 and No. 2001 -119316.


A computer is formed from modular parts that are vertically stacked relative to one another so that even a casual observer may become aware of all of the components of the observed computer system. Each part has a predetermined geometrical configuration and will interlock only with other parts of the same geometrical configuration. In this way, manufacturers of computer components may make parts that are compatible with one another in a common geometrical configuration so that a consumer buying a component need only match shapes to ensure compatibility. An added advantage of the structure is that it enables computer owners to visually display their computer components to their friends and associates, in contrast to present computer housings that hide components and make highly advanced computers look much like their outdated predecessors. A bus interconnects all components and a cooling shaft delivers cooling air to all components.

1. Field of the Invention
This invention relates, generally, to computer housings. More particularly, it relates to a computer housing that exposes the features of a computer to visual inspection.
2. Description of the Prior Art
All conventional personal computers, despite their age, look substantially alike. Unlike the automotive industry, the computer industry has chosen to maintain a relatively common exterior appearance for its new makes and models as they are introduced to the consuming public. As a result, the respective exterior housings of an older computer and a new computer share a substantially similar appearance. Thus, a casual observer cannot tell an old computer, lacking many features, from a new computer that is loaded with advanced features.
Many people take pride in their computers, and wish their new, improved computers looked different from their old ones. Under current technology, however, a person who has just spend a substantial sum of money in purchasing a new computer system or upgrading an older one has nothing to show to his or her friends; the new or improved computer will look much like the older one. This is a state of affairs quite different from the automobile industry, the housing industry, and the like, where a new purchase can be admired by all from a visual perspective.
Moreover, there are times when a computer user wants to know the status of a component, but cannot because the component is internal, i.e., inside the computer housing and thus not available for casual inspection. Many people buy external modems for this reason, i.e., they need to see the function lights of the modem and cannot do so if they purchase an internal modem. Unfortunately, external modems take up desk space.
What is needed, then, is a new type of computer housing. The improved housing would enable the proud owner of a new computer or a new computer component to visually display it to admiring friends. It would also enable computer users to visually ascertain the status of various computer components without forcing them to purchase external components of the kind that rob them of desk space.
Another problem in the computer industry is the problem of compatibility. Many consumers purchase new parts for their computers, in an attempt to upgrade performance, only to discover that the newly purchased component cannot be added to their existing system. Visual inspection of the new components is of little value because, again, the known components lack distinctive design features.
The worse-case scenario is when a new component is installed without knowledge that it is incompatible with the preexisting components, thereby frying the computer.
Thus, there is a clear need for a solution to the compatibility problem.
Still another problem of the current computer industry is the fact that many component makers are at the mercy of the large computer assemblers. Most name brand computer companies are mere assemblers; they manufacture no components whatsoever. The manufacturers of components are at the mercy of such assemblers, however; the component manufactuers lack the means to sell their components directly to consumers. There have been cases where advanced components were withheld from the market for up to a year by computer assemblers who want to sell their inventory of computers with old components before allowing the public to have access to the improved components. Such practice damages the public as well as the component manufaturers.
Thus, a need exists as well for a means that enables component manufacturers to sell their components directly to the public without the interference of computer assemblers.
However, in view of the art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in this art how the needed improvements in computer housings could be provided. Nor was it obvious how the compatibility and component availability problems could be solved.

Vertically stacked computer modules shaped to indicate compatibility with vertical cooling shaft extending throughout


A method and apparatus for tracing any node in an emulator, including hidden nodes of a circuit design, includes maintaining a correspondence between physically observable nodes and hidden nodes of the circuit design being emulated. The correspondence identifies how values of the hidden nodes are to be determined based on corresponding ones of the physically observable nodes. The value of a hidden node is determined by obtaining the values of the corresponding physically observable nodes and identifying the value of the hidden node based on the correspondence between the corresponding physically observable nodes and the hidden node.

1. Field of the Invention
The present invention relates to the field of emulation systems. More specifically, the present invention relates to methods and apparatus for tracing any node in an emulator.
2. Background Information
Emulation systems for emulating circuit designs are known in the art. Typically, prior art emulation systems are formed using conventional general purpose field programmable gate arrays (FPGAs). A circuit design to be emulated is "realized" on the emulation system by compiling a "formal" description of the circuit design, and mapping the circuit design onto the logic elements (LEs) of the FPGAs.
Emulation systems for emulating circuit designs are particularly valuable because they allow complex circuits to be emulated in both a cost-effective and time-effective manner. Such emulation systems are also valuable because they allow signals to be output from the FPGAs for testing and debugging the circuit designs, thereby providing for "tracing" of signals.
However, these conventional emulation systems have several disadvantages. These disadvantages include the limitation that the states of signals at nodes within the LEs are not observable. For example, combinatorial logic mapped onto an LE may include several nodes which do not have signals that are output by the LE and thus are not observable. These nodes are referred to as "hidden" nodes. These hidden nodes can be made unhidden by mapping one circuit element to each LE, however, such inefficient mapping would be extremely wasteful of the precious LE resources.
Thus, it is desirable to have an emulation system and methodology for operating therein for tracing any node in an emulation, including hidden nodes. As will be described in more detail below, the present invention provides for such an emulation system that achieves these and other desired results, which will be apparent to those skilled in the art from the description to follow.

Method and apparatus tracing any node of an emulation


Provided is a solid polyelectrolyte fuel cell capable of suppressing a gas leak between a fuel electrode film side and an oxide electrode film side by suppressing deterioration of a solid polyelectrolyte film on its peripheral side. A solid polyelectrolyte fuel cell includes: a cell in which electrode films are provided on one side and the other side of a solid polyelectrolyte film, respectively; a first gas diffusion layer provided so as to cover the electrode film on one side of the cell; a second gas diffusion layer provided so as to cover the electrode film on the other side of the cell; and separators provided on the one side and the other side of the cell, respectively, with the gas diffusion layers interposed therebetween. The solid polyelectrolyte fuel cell includes: first insulating layers which are provided between the solid polyelectrolyte film of the cell and the gas diffusion layers and have electrical insulating properties; and second insulating layers which are provided on peripheral edges of the gas diffusion layers and have electrical insulating properties.

1. Field of the Invention
The present invention relates to a solid polyelectrolyte fuel cell.
2. Description of the Related Art
FIG. 10 shows a schematic diagram of a main part of a conventional solid polyelectrolyte fuel cell.
As shown in FIG. 10, on one side of a solid polyelectrolyte film 111 having proton (H+) conductivity, a fuel electrode film 112 is attached, which contains catalytic metal such as Pt—Ru and has conductivity and gas permeability. On the other side of the solid polyelectrolyte film 111, an oxide electrode film 113 is attached, which contains catalytic metal such as Pt and has conductivity and gas permeability.
On a side of the fuel electrode film 112 that is an electrode film on one side of a solid polyelectrolyte film electrode conjugate (cell) including the solid polyelectrolyte film 111, the fuel electrode film 112, the oxide electrode film 113 and the like, a first gas diffusion layer 114 having conductivity and gas diffusivity is attached so as to surround and cover the fuel electrode film 112. In other words, the first gas diffusion layer 114, which is larger than the fuel electrode film 112, is attached so as to come into direct contact with the solid polyelectrolyte film 111 as well as the fuel electrode film 112. On a side of the oxide electrode film 113 that is an electrode film on the other side of the cell, a second gas diffusion layer 115 having conductivity and gas diffusivity is attached so as to surround and cover the oxide electrode film 113. In other words, the second gas diffusion layer 115, which is larger than the oxide electrode film 113, is attached so as to come into direct contact with the solid polyelectrolyte film 111 as well as the oxide electrode film 113.
On the one side and the other side of the cell, on which the gas diffusion layers 114 and 115 are attached, respectively, separators 116 having conductivity are provided, respectively. Specifically, in the separator 116 provided on the one side of the cell, a fuel gas passage for hydrogen gas and the like is formed. Moreover, in the separator 116 provided on the other side of the cell, an oxide gas passage for air, oxygen and the like is formed.
A periphery of the solid polyelectrolyte film 111, which is exposed from peripheries of the electrode films 112 and 113 and the gas diffusion layers 114 and 115, is held by the separators 116 with sealants 117 interposed therebetween.
Note that, in FIG. 10, the gas diffusion layers 114 and 115 are closely attached to end faces of the electrode films 112 and 113 without having spaces between the end faces thereof and the layers. However, in reality, the gas diffusion layers 114 and 115 may be attached so as to come into direct contact with the solid polyelectrolyte film 111 while having spaces between the end faces of the electrode films 112 and 113 and the layers.
In the conventional solid polyelectrolyte fuel cell 110 as described above, when fuel gas is supplied to the fuel gas passage of the separator 116 and oxide gas is supplied to the oxide gas passage of the separator 116, the fuel gas is supplied to the fuel electrode film 112 while being diffused in the first gas diffusion layer 114 and the oxide gas is supplied to the oxide electrode film 113 while being diffused in the second gas diffusion layer 115. Accordingly, the fuel gas and the oxide gas electrochemically react with each other. Thus, protons (H+) generated from hydrogen gas on the fuel electrode film 112 side move toward the oxide electrode film 113 within the solid polyelectrolyte film 111. At the same time, electrons (e−) generated from the hydrogen gas on the fuel electrode film 112 side flow toward the oxide electrode film 113 through the separator 116 and the second gas diffusion layer 115 from the first gas diffusion layer 114 and the separator 116 via an external electric circuit. Thus, electricity can be generated while generating water by allowing oxygen to react with the protons and the electrons on the oxide electrode film 113 side.
<Related Arts>
A. Japanese Patent No. 3271410
B. Japanese Patent No. 3345240
C. Japanese Patent Laid-Open Publication No. 2003-123777


A system and method for compensating for torque overshoot in a rotary power tool wherein the tool is shut off at an adjusted set point value of torque which is below the target value of torque by the amount of torque overshoot. While the tool is operated to perform a fastening job, the relationship between the torque rate in the fastening job to overshoot in the tool is determined, the torque rate in the job is monitored while the tool is setting the job, and the torque set point is adjusted while the tool is setting the job to compensate for the torque overshoot determined from the foregoing relationship. The relationship between torque rate in the fastening job and overshoot in the tool follows the expression Y=K/X where Y is the overshoot, X is the deceleration time required to tighten the fastener and K is a constant determined by using the measured deceleration time and torque overshoot during a previous high torque rate job in the foregoing expression, the deceleration time being measured between the same selected fractional values of the target torque. During a subsequent fastening job, the deceleration time is measured between the same selected fractional values of target torque, the overshoot is calculated from the foregoing mathematical expression using the previous value of K, and the torque set point is adjusted to compensate for the calculated value of overshoot. The foregoing is performed job-to-job developing a running average of the constant K. While the use of torque-time rates is preferred for simplicity and economy, the use of torque-angle rates also is contemplated.

This invention relates to rotary power tools and, more particularly, to a new and improved control system and method to compensate for torque overshoot in such tools.
One area of use of this invention is in tightening threaded fasteners, although the principles of the present invention can be variously applied. In a typical power tool system to which the present invention relates, the fastening tool contains a torque transducer connected to a microprocessor-meter combination. In such a controlled tool, an analog torque signal is fed from the torque transducer in the tool to the microprocessor-meter in which a torque target has been set. When that target is reached, a control signal is sent from the meter to shut off the tool. In a fluid operated tool the shut off mechanism may be a solenoid-actuated valve in the tool. On an electric tool, shut off may be accomplished through an electronic switch. On a high torque-rate threaded joint, inertia in the decelerating high-speed elements in the tool can potentially drive the final tool torque well beyond the stall torque of the tool, and shut off or braking mechanisms cannot react quickly enough to prevent torque overshoot above the target torque set on the meter.
One way to correct the foregoing problem is to measure the amount of overshoot and adjust the set point on the meter downward so that the overshoot brings the final torque up to the target torque. Some presently available controls have built-in circuits to make this adjustment automatically, in effect learning the proper compensating set point after a few runs. The problem with this approach is that the torque rate of fastening jobs is seldom uniform, so that the amount of overshoot varies. A control which has learned to lower the set point from previous runs on high torque-rate jobs will yield a low final torque when the torque rate of the next job is suddenly low.
It would, therefore, be highly desirable to provide a system and method to compensate for torque overshoot which teaches the control the dynamic character of the power tool in use, in particular finding the curve, i.e., a mathematical function, which relates torque rate in the particular fastening job to overshoot in the tool. Then inspection or monitoring the torque rate of a job is effected while the tool is actually setting the job so that the torque set point can be lowered in precisely the correct amount to compensate for the overshoot related to that torque rate.

Power tool compensator for torque overshoot


The present invention relates to rifamycin 3-iminomethylenyl (—CH═N—) derivatives having antimicrobial activities, including activities against drug-resistant microorganisms. The claimed rifamycin derivative has a rifamycin moiety covalently linked to a linker through an iminomethylenyl (—CH═N—) group at the C-3 carbon of the rifamycin moiety and the linker is, in turn, covalently linked to a quinolone structure or its pharmacophore within the DNA gyrase and topoisomerase IV inhibitor family. The inventive rifamycins are novel and exhibit activity against both rifampin and ciprofloxacin-resistant microorganisms.

This invention relates to compounds of rifamycin derivatives having antimicrobial activities, their compositions, and methods for treatment and prevention of microbial infections. More particularly, the rifamycin derivative of the current invention is a rifamycin moiety covalently linked to a linker through an iminomethylenyl group (—CH═N—) at the C-3 carbon of the rifamycin moiety and the linker is, in turn, covalently linked to a quinolone moiety. The rifamycin derivatives are active against drug-resistant microorganisms with reduced frequency of developing mutational resistance in the microorganisms.
Rifamycins are natural products with potent antimicrobial activity. Examples of the naturally-occurring rifamycins are rifamycin B, rifamycin O, rifamycin R, rifamycin U, rifamycin S, rifamycin SV and rifamycin Y (Brufani, M., Cerrini, S., Fedeli, W., Vaciago, A. J. Mol. Biol. 1974, 87, 409-435). The therapeutic applications of the naturally-occurring rifamycins are limited due to their poor pharmacokinetics and oral bioavailability, weak activity against Gram-negative pathogens and low distribution into the infected tissues. Significant efforts have been made toward identifying semi-synthetic rifamycin derivatives to address the deficiencies. As a result, many semi-synthetic rifamycin derivatives with improved spectrum and pharmacological profiles have been identified. Among the semi-synthetic compounds, rifampin, rifabutin and rifapetine have been developed into therapeutic agents and are currently used for the treatment of tuberculosis and other microbial infections (Farr, B. M. Rifamycins, in Principles and Practice of Infectious Diseases; Mandell, G. L., Bennett, J. E., Dolin, R., Eds.; Churchhill Livingstone: Philadelphia; p348-361).
At present, one of the major problems associated with the rifamycin class of antimicrobial agents, like rifampin, is their rapid development of microbial resistance. Mutations in the target RNA polymerase are mainly responsible for the high frequency of microbial resistance to rifamycins. Consequently, rifamycins are currently used only in combination therapies with other antibiotics to minimize the development of resistance to this class of drugs. Rifamycin compounds of the current invention are designed to address both the rifamycin and quinolone resistance problems by attaching a quinolone core or quinolone antibiotic pharmacophore to the C-3 position of the rifamycin core structure. The resulting rifamycin compounds exert their antimicrobial activity through multiple antibacterial mechanisms targeting bacterial RNA polymerase, DNA gyrase and DNA topoisomerase IV and therefore exhibit reduced frequency of resistance.
Reference is made to U.S. Pat. No. 5,786,350 that discloses a series of C-36 derivatives of rifamycin, including derivatives formed by linking the C-3 carboxy group of a quinolone to the C-36 position of a rifamycin molecule through a chemically or metabolically labile ester group. The compounds of the current invention are structurally distinct from the previously disclosed compounds in several ways: 1) the linking point of rifamycin is the C-3 position rather than the C-36 position; 2) the linking point of the quinolone core is the C-7 position of the quinolone rather than the C-3 position carboxylic acid; and 3) the linker group contains a stable hydrazone linkage in the current inventive rifamycins rather than a metabolically unstable ester in the referenced compounds.
Reference is also made to PCT application WO 03/045319 A2 that discloses rifamycin derivatives formed by linking rifamycin and a therapeutic drug and the use of these rifamycin derivatives as vehicles for delivering the therapeutic drug. The current non-pro-drug invention differs from the referenced pro-drug strategy. In addition, this reference failed to demonstrate by specific examples that any drug is introduced to the C-3 position of a rifamycin molecule. The reference also failed to demonstrate by example that a quinolone antibiotic or its pharmacophore structure is linked to any position of rifamycin molecule.

Rifamycin imino derivatives effective against drug-resistant microbes


There is provided a feed-forward amplifier which enables a predistortion circuit to obtain sufficient distortion compensation effects even if ambient temperature or the like changes. The feed-forward amplifier includes a variable attenuator for controlling the amount of attenuation of a signal input to a main amplifier, a variable attenuator for controlling the amount of attenuation to prevent deterioration of distortion compensation due to a change in the ambient temperature of the main amplifier, a variable attenuator for controlling the amount of attenuation of a signal input to an auxiliary amplifier, and a variable attenuator for controlling the amount of attenuation to prevent deterioration of distortion compensation due to a change in the ambient temperature of the auxiliary amplifier, wherein a control circuit controls the variable attenuators to reduce the amount of attenuation according to the reduced gain of the main amplifier and the reduced gain of the auxiliary amplifier, and a control circuit controls the variable attenuators to optimize the amount of attenuation according to the ambient temperature of the main amplifier and the ambient temperature of the auxiliary amplifier.

1. Field of the Invention
The present invention relates to a feed-forward amplifier having a predistortion circuit (predistortion compensator), and particularly to a feed-forward amplifier that enables the predistortion circuit to obtain distortion compensation effects even if ambient temperature or the like changes.
2. Description of the Related Art
Recently, various developments have been made for feed-forward amplifiers.
When a feed-forward amplifier amplifies a modulation wave signal having in general a high peak-to-average power ratio, if the back-off of the amplifier is decreased to increase efficiency, linearity is deteriorated and hence large distortion occurs. On the contrary, if the back-off is increased to improve linearity, efficiency is reduced.
For example, there is a feed-forward amplifier shown in FIG. 2 as a method of compensating non-linear distortion caused by small back-off. FIG. 2 is a circuit block diagram of a feed-forward amplifier according to a first prior art (prior art 1).
As shown in FIG. 2, in the feed-forward amplifier of the prior art 1, a signal input from an input terminal 1 is divided by a divider 2. One divided signal passes through a variable attenuator 4 and a variable phase-shifter 5. Then, a pilot signal generated from a pilot signal generator 16 is inserted into the signal, and input to a main amplifier 6. The variable attenuator 4 and the variable phase-shifter 5 are controlled by a control circuit 19.
On the other hand, the other signal divided by the divider 2 is delayed through a delay line 10 and input to a combiner 11.
The output of the main amplifier 6 is input to a divider 7. One divided signal is input to a combiner 9 through a delay line 8 and the other divided signal is input to the combiner 11.
The combiner 11 combines the signal that has passed through the delay line 10 with the output of the divider 7. The output of the combiner 11 passes through a variable attenuator 12 and a variable phase-shifter 13 and is input to an auxiliary amplifier 14. The variable attenuator 12 and the variable phase-shifter 13 are controlled by the control circuit 19.
The output of the auxiliary amplifier 14 is combined by the combiner 9 with the signal that has passed through a delay line 8, and output from an output terminal 15.
A carrier component is detected by a carrier detector 17 at an output point of the combiner 11, and this detected carrier level is input to the control circuit 19. Further, a pilot signal level inserted by a pilot signal detector 18 is detected at an output point of the combiner 9 and input to the control circuit 19.
Next, the operation of the feed-forward amplifier of the prior art 1 will be described.
The signal input from the input terminal 1 is divided by the divider 2, and the divided signals are output to one signal path and the other signal path, respectively. The signals that have passed through one signal path and the other signal path are combined by the combiner 11, and a carrier component of the combined output is detected by the carrier detector 17 and input to the control circuit 19.
The control circuit 19 controls the variable attenuator 4 and the variable phase-shifter 5 in such a manner to minimize the output of the carrier detector 17. Since control is thus performed, one signal path and the other signal path exhibit the same amplitude but opposite phase so that only the distortion component of the main amplifier 6 is extracted from the output of the combiner 11.
Further, the distortion component extracted by the combiner 11 passes through the variable attenuator 12 and the variable phase-shifter 13, and after amplified by the auxiliary amplifier 14, it is combined by the combiner 9 with the signal that has passed through the delay line 8. A pilot signal component contained in the output of the combiner 9 is detected by the pilot detector 18 and input to the control circuit 19.
The control circuit 19 controls the variable attenuator 12 and the variable phase-shifter 13 in such a manner to minimize the output of the pilot detector 18. Since control is thus performed, the one signal path and the other signal path divided by the divider 7 exhibit the same amplitude but opposite phase so that the distortion generated by the main amplifier 6 can be cancelled out.
However, in the feed-forward amplifier shown in FIG. 2, the amount of compensation needs to be increased to assure an equivalent distortion amount in the feed-forward amplifier as the amount of distortion generated by the main amplifier 6 increases.
In this case, although the auxiliary amplifier 14 needs to be replaced with an amplifier having high output power to improve the linearity of the auxiliary amplifier 14, the efficiency of the feed-forward amplifier is reduced.
Even if the main amplifier 6 is replaced with an amplifier having high output power to reduce the amount of distortion generated by the main amplifier 6, the efficiency of the feed-forward amplifier is also reduced.
On the other hand, there is also known a method of providing a predistortion circuit on the input side of the main amplifier 6 to correct AM-AM characteristics and AM-PM characteristics of the amplifier in order to reduce the distortion of the amplifier with the same back-off.
An example of the feed-forward amplifier including a predistortion circuit is disclosed in Japanese Patent No. 2047120. FIG. 3 shows a block diagram thereof. FIG. 3 is a circuit block diagram of a feed-forward amplifier according to a second prior art (prior art 2).
As shown in FIG. 3, the feed-forward amplifier of the prior art 2 has a distortion detection loop 100 for detecting a distortion component of a main amplifier 106 and a distortion removing loop 200 for inserting the detected distortion component into an output signal path 114 of the main amplifier 106 to remove the detected distortion component.
In the distortion detection loop 100, a predistortion circuit (predistortion compensator) 120A is provided on the input side of the main amplifier 106 to improve the distortion of this main amplifier 106, while a variable attenuator 108 or the like for control of the distortion detection loop 100 is included in a variable delay line 109.
The following describes the operation of the feed-forward amplifier of the prior art 2.
A signal input from an input terminal 101 is divided by a power divider 103. One divided signal passes through the predistortion circuit 120A and the main amplifier 106, and is input to a power combiner 104.
On the other hand, the other output of the power divider 103 passes through the variable attenuator 108 and the variable delay line 109, and is input to the power combiner 104 and combined with the output of the main amplifier 106. The same component as that from the main amplifier 106 is supplied from the power combiner 104 into the output signal path 114 of the main amplifier 106, and the distortion component of the main amplifier 106 detected in the distortion detection loop 100 is output to a distortion insertion path 115.
The signal in the distortion insertion path 115 passes through a variable attenuator 110 and a variable delay line 111, and after amplified by an auxiliary amplifier 107, it is combined by a power combiner 105 with the signal sent from the main amplifier 106 through the output signal path 114. The output of the power combiner 105 is output from an output terminal 102.
Further, FIG. 4 shows another example of a feed-forward amplifier circuit according to another prior art (prior art 3) disclosed in Japanese Patent No. 2047120. In FIG. 4, portions equivalent to those in FIG. 3 are given the same reference numerals.
In the example of the prior art 3, the distortion insertion path 115 passes through the variable attenuator 110, the variable delay line 111, and a predistortion circuit 120B and is input to the auxiliary amplifier 107.
The predistortion circuit 120B is provided to improve the distortion of this auxiliary amplifier 107. The other portions are the same as those in FIG. 3.
There are the following problems in the prior arts (prior arts 2, 3) shown in FIGS. 3 and 4.
The first problem is that if the gain of the main amplifier 106 varies due to a change in ambient temperature or the like, the amount of distortion generated by the main amplifier 106 varies due to a change in output level. In this case, since the amount of distortion compensation in the predistortion circuit 120A is constant, the distortion of the main amplifier 106 cannot be compensated.
In the feed-forward amplifier circuit, when the gain of the main amplifier 106 varies due to a change in ambient temperature, the variable attenuator 108 inserted in a linear signal path 113 generally needs to be adjusted in such a manner that a signal path 112 of the main amplifier 106 and the linear signal path 113 will exhibit the same gain but opposite phase in order to perform distortion extraction correctly. However, in the feed-forward amplifier circuits shown in FIGS. 3 and 4, since the variable attenuator 108 is inserted in the linear signal path 113, the output level of the main amplifier 106 remains varying.
The second problem is that if the gain of the auxiliary amplifier 107 varies due to a change in ambient temperature or the like, the amount of compensation of the predistortion circuit 120B varies so that the distortion of the auxiliary amplifier 107 cannot be compensated.
In the feed-forward amplifier circuit, when the gain of the auxiliary amplifier 107 varies due to a change in ambient temperature, the variable attenuator 110 generally needs to be controlled in such a manner that the output signal path 114 of the main amplifier 106 and the distortion insertion path 115 will exhibit the same gain but opposite phase in order to remove the distortion correctly. However, in the conventional feed-forward amplifier circuits in which the variable attenuator 110 is provided prior to the predistortion circuit 120B, the input level of the predistortion circuit 120B varies to change the amount of compensation.
In order to solve such problems, still another example of a feed-forward amplifier is disclosed in Japanese Patent No. 3106996 as shown in a block diagram of FIG. 5. FIG. 5 is a circuit block diagram of the feed-forward amplifier of the prior art (prior art 4) disclosed in Japanese Patent No. 3106996.
As shown in FIG. 5, the feed-forward amplifier of the prior art 4 is such that a signal input from the input terminal 1 is divided by the divider 2 into a signal path (a) and a signal path (b). One signal output to the signal path (a) side passes through the predistortion circuit 3, the variable attenuator 4, and the variable phase-shifter 5. Then, after the pilot signal generated from the pilot signal generator 16 is inserted, the one signal is input to the main amplifier 6.
Here, the variable attenuator 4 and the variable phase-shifter 5 are controlled by the control circuit 19.
On the other hand, the output of the main amplifier 6 is input to the divider 7 in such a manner that one divided output is input to the combiner 9 via the delay line 8 and the other divided output is input to the combiner 11.
The combiner 11 combines the signal that has passed through the delay line 10 with the output of the divider 7. The output of the combiner 11 passes through the variable attenuator 12, and the variable phase-shifter 13 and is input to the auxiliary amplifier 14.
The variable attenuator 12 and the variable phase-shifter 13 are controlled by the control circuit 19.
The output of the auxiliary amplifier 14 is combined by the combiner 9 with the signal that has passed through the delay line 8, and output from the output terminal 15.
A carrier component (as a single frequency component of the signal supplied to the input terminal 1 and to be amplified) is detected by the carrier detector 17 at the output point of the combiner 11, and the detected carrier level is input to the control circuit 19.
Next, the operation of the feed-forward amplifier of the prior art 4 will be described.
The signal input from the input terminal 1 is divided by the divider 2 into the signal path (a) and the signal path (b). The signal path (a) and the signal path (b) are combined by the combiner 11. The combined output of the carrier component is detected by the carrier detector 17 and input to the control circuit 19.
The control circuit 19 controls the variable attenuator 4 and the variable phase-shifter 5 in such a manner to minimize the output of the carrier detector 17. Since control is thus performed, the signal path (a) and the signal path (b) exhibit the same amplitude but opposite phase, so that only the distortion component of the main amplifier 6 is extracted from the output of the combiner 11.
Further, a predistortion circuit 3 is used in the signal path (a) to minimize the distortion of the main amplifier 6. The distortion component extracted by the combiner 11 passes through the variable attenuator 12 and the variable phase-shifter 13, and after amplified by the auxiliary amplifier 14, it is combined by the combiner 9 with the signal that has passed through the delay line 8.
The pilot signal component contained in the output of the combiner 9 is detected by the pilot detector 18 and input to the control circuit 19. The control circuit 19 controls the variable attenuator 12 and the variable phase-shifter 13 in such a manner to minimize the output of the pilot detector 18. Since control is thus performed, a signal path (c) and a signal path (d) exhibit the same amplitude but opposite phase so that the distortion generated by the main amplifier 6 can be cancelled out.
Referring next to FIG. 6, the operation of the feed-forward amplifier of the prior art 4 shown in FIG. 5 will be described on condition that ambient temperature changes. FIG. 6 contains graphs showing the characteristics of the amplifier of the prior art 4, where FIG. 6A shows the relationship between temperature and gain, and FIG. 6B shows the relationship between temperature and distortion.
It is generally known that a power amplifier used as the main amplifier 6 reduces its gain at higher temperatures as shown in FIG. 6A as ambient temperature changes. It is also generally known that the generated distortion component depends more largely upon output power than upon ambient temperature, that is, the generated distortion component increases as the output level increases as shown in FIG. 6B.
Suppose that ambient temperature increases in the circuit shown in FIG. 5. In this case, the gain of the main amplifier 6 is reduced as shown in FIG. 6A as ambient temperature increases. In this condition, since the signal path (a) and the signal path (b) are different in amplitude, the carrier component combined by the combiner 11 is output from the combiner 11 without being totally cancelled out. The carrier component output from the combiner 11 is detected by the carrier detector 17 and input to the control circuit 19.
The control circuit 19 controls the variable attenuator 4 and the variable attenuator 5 to minimize the output of the carrier detector 17. Therefore, the amount of attenuation of the variable attenuator 4 is reduced as much as the reduced amount of gain of the main amplifier 6 so that the output of the carrier detector 17 will be minimized again. Such an operation results in keeping the output level of the main amplifier 6 constant. Further, the predistortion circuit 3 operates at a constant level irrespective of the above-mentioned operation because it is located prior to the variable attenuator 4.
Referring next to FIG. 7, another example (prior art 5) of a feed-forward amplifier disclosed in Japanese Patent No. 3106996 will be described. FIG. 7 is a circuit block diagram of the feed-forward amplifier of the prior art 5. In FIG. 7, portions equivalent to those in FIG. 5 are given the same reference numerals.
As shown in FIG. 7, a predistortion circuit 20 is provided between the combiner 11 and the variable attenuator 12 in the feed-forward amplifier of the prior art 5.
Like the circuit example shown in FIG. 5, the operation of the feed-forward amplifier of the prior art 5 shown in FIG. 7 will be described on condition that ambient temperature changes.
A power amplifier used as the auxiliary amplifier 14 also reduces its gain at higher temperatures generally as shown in FIG. 6(a) as ambient temperature changes. The generated distortion also depends more largely upon output level than upon ambient temperature, that is, the generated distortion increases as the output level increases as shown in FIG. 6(b).
Suppose that ambient temperature increases in the feed-forward amplifier of the prior art 5 shown in FIG. 7. In this case, the gain of the auxiliary amplifier 14 is reduced as shown in FIG. 6(a) as ambient temperature increases. In this condition, since the signal path (c) and the signal path (d) are different in amplitude, the pilot signal inserted and combined by the combiner 9 is output from the combiner 11 without being totally cancelled out. The pilot signal output from the combiner 9 is detected by the pilot signal detector 18 and input to the control circuit 19.
The control circuit 19 controls the variable attenuator 12 and the variable phase-shifter 13 to minimize the output of the pilot signal detector 18. Therefore, the amount of attenuation of the variable attenuator 12 is reduced as much as the reduced amount of gain of the auxiliary amplifier 14 so that the output of the pilot signal detector 18 will be minimized again. Such an operation results in keeping the output level of the auxiliary amplifier 14 constant. Further, the predistortion circuit 20 operates at a constant level irrespective of the above-mentioned operation because it is provided prior to the variable attenuator 12.
However, variations in characteristics of the conventional feed-forward amplifiers include not only variations in gain due to changes in ambient temperature as the temperature of the amplifier increases, but also variations in maximum output power thereof. In other words, the gain and hence the maximum output power are reduced as temperature increases as shown in FIG. 8. FIG. 8 is a graph showing examples of amplitude characteristics (AM-AM characteristics) with respect to the output power varying with the temperature of the amplifier. FIG. 8 shows the gain with respect to the output power varying with three kinds of temperatures.
When gain in a path from a predistortion circuit to an amplifier is made constant, the start point of gain expansion performed by the predistortion circuit dose not change because input power and gain of the predistortion circuit are constant regardless of the fact that the maximum output power of the amplifier is reduced to change the start point of gain compression. This causes a problem that the optimum point of distortion compensation of the amplifier by using the predistortion circuit can shift, and hence the optimum distortion compensation cannot be obtained.


The present invention relates to a fixing member having high abrasion resistance and being excellent in toner releasability, and a method of manufacturing the fixing member. The fixing member according to the present invention includes: a base member; an elastic layer formed on a surface of the base member; and a surface layer, in which the surface layer contains a tetrafluoroethylene-hexafluoropropylene copolymer having a specific partial structure and has a surface that forms a contact angle of 65° or more with respect to a wetting tension test mixture having a wetting tension of 31.0 mN/m.

Field of the Invention
The present invention relates to a fixing member to be used in a heat-fixing device of an electrophotographic image forming apparatus, a method of manufacturing the fixing member, a fixing device, and to an image forming apparatus.
Description of the Related Art
As a fixing member to be used in a heat-fixing device of an electrophotographic image forming apparatus such as a printer, a copying machine, or a fax machine, there is given a fixing member having a film shape or a roller shape. As such fixing member, there has been known a fixing member that includes a film-shaped or roller-shaped base member made of a heat-resistant resin or a metal, an elastic layer made of a heat-resistant rubber or the like formed on the base member, as necessary, and a surface layer containing a fluororesin having an excellent releasability with respect to toner. In this case, as the fluororesin to be contained in the surface layer, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) excellent in heat resistance is preferably used.
Meanwhile, in recent years, the durability required of the fixing member tends to increase further along with an increase in printing speed. The fluororesin layer on a surface of the fixing member is chipped due to abrasion between the fluororesin layer and paper, and hence the durability of the fixing member is secured through the thickness of the fluororesin layer. Therefore, in order to increase the durability of the fixing member, a large number of studies for improving abrasion resistance of the fluororesin layer have been conducted.
In Japanese Patent Application Laid-Open No. 2010-181621, which discloses the invention relating to a non-rotary pressing member arranged on a fixing unit of an electrophotographic image forming apparatus, it is disclosed that the abrasion resistance of a crosslinked fluororesin layer formed through Steps 1 to 4 is significantly improved.
Step 1 of forming an unbaked and uncrosslinked fluororesin layer on a base member;
Step 2 of baking the fluororesin layer by heating the fluororesin layer at a temperature within a range of from a melting point (Tm) of the fluororesin to a temperature higher by 150° C. than the melting point thereof (Tm+150° C.);
Step 3 of adjusting the temperature of the baked uncrosslinked fluororesin layer at a temperature within a range of from a temperature lower by 50° C. than the melting point of the fluororesin (Tm−50° C.) to a temperature higher by 50° C. than the melting point thereof (Tm+50° C.); and
Step 4 of crosslinking an uncrosslinked fluororesin by irradiating the uncrosslinked fluororesin layer adjusted for temperature with a radiation having a radiation dose within a range of from 1 to 1,000 kGy in an atmosphere having an oxygen concentration of from 0.1 to 1,000 ppm.
In addition, in Japanese Patent Application Laid-Open No. 2010-181621, as specific examples of the fluororesin, there are given polytetrafluoroethylene (PTFE), a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and a tetrafluoroethylene-hexafluoropropylene copolymer (FEP).

Fixing member and manufacturing method therefor, fixing device, and image forming apparatus