A method for managing the detection of advertising sequences in a stream of information stored on a mass memory module of an electronic apparatus, the information stream corresponding to an extract of a television program, the information stream including a first set of information corresponding to a content to be rendered and a second set of information, corresponding to the advertising sequences, the information stream including at least one set of video information, and teletext type data, and subtitle data associated with the stream, the method including analyzing the video information for detecting a format transition in the images associated with the video information; optionally storing a first address information corresponding to the detected transition, and validating a first detection condition; analyzing the teletext type data for detecting an absence, and then a presence, of teletext subtitles associated with the video information, optionally storing a second address information corresponding to the detected, transition, and validating a second detection condition; analyzing the subtitle data associated with the stream for detecting an absence, then a presence of the subtitle data associated with the stream; optionally storing third address information corresponding to the detected transition, and validating a third detection condition; if the three detection conditions are validated, identifying the stored address information as transition sequences between the second set of information and the first set of information.

Henceforth, many digital television decoders are equipped with a hard drive type memory unit, a large capacity memory enabling the storage of, for example, several cinema films. The storing duration henceforth reaches several dozen hours. Thus, an essential advantage of a digital television decoder equipped with a hard drive is that it makes it possible for the user to facilitate the recording of television programs and to watch them in a delayed-repeater mode; furthermore, the user has tools, particularly his/her remote-control which make it possible to set up a rapid navigation in the different programs he/she recorded on his/her hard drive, and in particular to rapidly run the advertising sequences which are inserted in the television program he/she recorded and is viewing on his/her screen.
Currently, the user has to search the end of the advertizing sequences by himself, using his/her remote control, and particularly the functions of fast forwarding and fast rewinding the contents stored on the hard drive. Such an action is time consuming, and is fastidious due to the many manipulations it requires to stop exactly at the end of the advertizing sequence.

Method for managing advertising detection in an electronic apparatus, such as a digital television decoder


An integrated circuit includes a memory core and a built-in self-test (BIST) controller. The memory core has an array of memory cells located at intersections of a plurality of word lines and a plurality of bit line pairs. The BIST controller is coupled to the memory core and has a mission mode and a built-in self-test mode. When in the mission mode, the BIST controller performs read and write accesses using precharge on demand. When in the built-in self-test mode, the BIST controller performs a floating bit line test by draining a voltage on true and complement bit lines of a selected bit line pair and subsequently precharging the true and complement bit lines of the selected bit line pair, before reading or writing data using the true and complement bit lines of the selected bit line pair.

Static random-access memory (SRAM) is a type of semiconductor memory that uses bi-stable latching circuitry to store binary bits of data. SRAM cells have the advantage of holding data without requiring a refresh. SRAM is volatile because data is lost when the memory is not powered. In an SRAM array or sub-array, an addressed memory cell is at the intersection of a selected row (identified by a word line) and a selected column (typically identified by a bit line pair having a true bit line and a complement bit line). Bit lines are typically metallic conductors disposed perpendicularly to the word lines and are physically connected to the source/drains of memory cell access transistors and are the conductors through which information is written to and read from the memory cells.
One common use for large SRAM arrays in modern integrated circuit design is as data and tag storage for data processing caches. Cache SRAM arrays are relatively large, such as 32 megabytes, and therefore can take a long time to test. In order to test large SRAM arrays efficiently, circuit designers often add special-purpose testing circuits, known as built-in self-test (BIST) circuits, that can be activated to automatically test the memory cells and access circuitry in the SRAM array and reduce overall test time. A BIST controller typically performs patterns of write and subsequent read cycles to detect failures under a variety of conditions. However, it is difficult even for BIST controllers to test all memory cells under all operating conditions that may result in a failure during normal operation in the field, such as testing of accesses after startup or other transient conditions.
In the following description, the use of the same reference numerals in different drawings indicates similar or identical items. Unless otherwise noted, the word "coupled" and its associated verb forms include both direct connection and indirect electrical connection by means known in the art, and unless otherwise noted any description of direct connection implies alternate embodiments using suitable forms of indirect electrical connection as well. Additionally, the terms remap and migrate, and variations thereof, are utilized interchangeably as a descriptive term for relocating.

Integrated circuit memory with built-in self-test (BIST)


A method of manufacturing an electromechanical locker system may include providing a set of lockers with coin-operated locks. The coin-operated locks may be removed from the set of lockers. A conduit may be extended along and connected to a frame member from which the coin-operated locks had previously been positioned. Electromechanical lock units may be attached to the conduit so as to replace the coin-operated locks. A retrofitted coin-operated locker bank may include a coin-operated locker bank including a multiple lockers having respective doors, where the coin-operated locker bank is free of coin-operated locks. A conduit may be connected to a frame member and extend vertically adjacent to the hinged doors of a column of lockers. Multiple electromechanical lock units may be attached to the conduit so as to replace the coin-operated locks.

Lockers for rental have traditionally been configured to enable people to deposit coins, such as quarters, into the locks, which have traditionally been mechanical, coin-operated locks. Upon the locks receiving certain monetary value, a person can turn a key from an unlocked position to a locked position with a door of a locker being rented in a closed position, and, upon being turned to the locked position, the key can be withdrawn from the lock. The person can later access the locker by inserting the key back into the lock and turning the key back to the unlocked position.
While the coin-operated locks provide a certain level of convenience for users, the coin-operated locks have limitations. For example, society has been transitioning from a cash-based payment society to a card-based payment society. Thus, people are now as much or more comfortable with using credit cards, debit cards, or prepaid cards as they are using cash, and often do not carry cash, especially to entertainment and activity venues, such as amusement parks and ski slopes, where coin-operated lockers are generally located. Another problem that exists with coin-operated lockers is that people can lose the key and be inconvenienced when needing to access the locker. Of course, in the event of a lost key, the locker owner is inconvenienced and costs result by having to replace the lost keys.
Because the lockers are expensive to replace, owners of the coin-operated lockers tend to not replace the coin-operated lockers despite their shortcomings, as described above. These lockers are generally durable and formed of stainless steel, so last for many years for both the locker owner and facility owner, which, in some cases, are one and the same.

This patent is subject to a terminal disclaimer.

System and method for retrofitting coin-operated lockers


The present invention provides a method and device for to implement time division multiplexing of a fiber optic serial Bragg grating sensor array containing more than one Bragg grating. The device provides a pulse read-out system that allows for a reduction in system noise and an increase in sensor resolution and flexibility. The optical signals reflected from the Bragg grating sensors are gated by an electronically controlled optical modulator before any wavelength measurement is performed to determine the sensor information. This offers significant advantages since the sensor information is encoded into the wavelength of the optical signal and not its intensity. Therefore the sensor signal information is not distorted by the gating. Since the gating or switching of the optical modulator between transmission and attenuating states is performed on the optical signal, the speed of the electronic processing needs only to be performed at the speed of variation of the sensor information and the choice of methods of wavelength measurement is not influenced by the gating action.

Fiber optic Bragg gratings may be used as sensors to monitor perturbations in their environment. A Bragg grating is formed in a single mode optical fiber by creating a periodic refractive index perturbation in the fiber core as described by Kawaski, Hill, Johnson and Fuhjii in Optics Letters, Vol. 3, pp. 66-68, 1978. The diffraction grating in the fiber core will reflect optical frequencies within a narrow bandwidth around the Bragg wavelength of the optical grating. The Bragg wavelength of the diffraction grating can be altered by changing the grating pitch. If an external influence alters the grating pitch then the reflection spectrum of the grating can be monitored to determine the magnitude of the external influence. If the grating is subject to varying strain or temperature, the pitch of the grating is altered as described by Morey, Meltz and Glenn in the Proceeding of the IEEE, vol. 1169, pp. 98-107, 1989. By coupling the grating to an appropriate transducer, the grating can be used to monitor a wide variety of parameters including but not limited to strain, temperature, vibration, pressure, and acceleration.
Fiber optic Bragg grating sensors offer many advantages over traditional electrical sensors for monitoring the various parameters. They provide inherent immunity to electromagnetic interference and provide a reliable signal with very little noise. They can also withstand large variations in temperature and pressure and are compact in size allowing them to be used in locations where conventional sensors are impractical. Bragg grating fiber sensors have the additional advantage that the signal is encoded directly into an absolute wavelength shift of the optical signal, so the signal is insensitive to optical power fluctuations and other signal perturbations.
Unfortunately, the design of Bragg grating sensor systems is often more costly than the conventional electrical sensor alternatives and this has prevented their widespread adoption in many applications. To increase the utility of Bragg grating sensors, it would be advantageous to be able to multiplex many grating sensors in the same optical fiber in order share expensive resources such as the optical source and the sensor measurement unit among the many sensors thereby dramatically reducing the cost per sensor. The placement of many sensors in the same fiber often simplifies the installation of the sensors in structures or systems by reducing bulk and complexity. It is also desirable that the functionality and performance of the system not be degraded by the multiplexing technique.
These potential advantages have motivated significant efforts into developing methods of multiplexing Bragg grating sensors. It would be very beneficial to be able to multiplex a hundred sensors or more in a single optical fiber using only one light source and spectral measurement system. Current systems have fallen short of this goal with about ten sensors per fiber in demonstrated systems that do not severely restrict the sensor's application. As the number of sensors grows there is an increased demand on the optical source power and the complexity of the multiplexing and/or demultiplexing. For a very large number of sensors the cross talk between the sensors can become a significant problem.
Many different multiplexing techniques have been developed for Bragg grating sensors. The most successful techniques for use with a large number of sensors have been wavelength division and time division multiplexing. Examples of these systems are described in the paper by Kersey et al. in the Journal of Lightwave Technology vol. 15, pp.1442-1462, 1997.
In wavelength division multiplexing, the Bragg wavelength of each sensor is set at a separate and unique wavelength. The separations of the Bragg wavelengths are made to be far enough apart so that any reasonable external influence to the grating sensors will not be sufficient to cause the Bragg wavelengths of any two sensors to overlap. Thus each sensor is given a unique wavelength band or slot for its Bragg wavelength. In many situations, the size of each wavelength slot may need to be very large. This requirement can result from the necessity to be able to detect a large range of the parameter being sensed or due to the fact there may be uncertainty in the nominal Bragg wavelength of the sensors. Uncertainty may arise from variations in the fabrication process of the gratings, by static strains or uncertain operating temperatures when the sensor is used. The variability can necessitate a wavelength slot for each sensor in excess of 15 nm for Bragg wavelengths near 1550 nm. When the number of multiplexed sensors is large, the bandwidth requirement on the optical source can become intractable thus limiting wavelength division multiplexing to well controlled sensors that are subject to small external influences.
To overcome the aforementioned problems associated with limited optical bandwidth, the Bragg wavelengths of the sensors may be fabricated with nearly identical Bragg wavelengths and multiplexed with time division multiplexing. In this method a short optical pulse is sent along the fiber containing the Bragg sensors. The pulse will partially reflect off of each sensor and return the sensor information from each grating. The signals from each sensor can be distinguished by their time of arrival. Previous demonstrations of time division multiplexing have determined the time of arrival of the signal by converting the optical pulses into an electrical signal and then gating the electrical signal with a known time delay. Only the pulse that is passing through the electronic detector at the time of the gate is measured. By varying the time delay of the gate, the signals from each of the sensors can be read out.
A previous method used in the art to identify the sensor signals is to electrically gate the sensor signals as disclosed in U.S. Pat. No. 5,680,489. Since the sensors are now identified by time discrimination instead of wavelength, bandwidth requirements of the source will not limit the number of sensors. However, different problems can be encountered in time division multiplexing that can limit the performance of the system. Time division multiplexed systems generally experience more noise than wavelength division multiplexed systems. A significant contribution of the noise is from multiple reflection between the different grating sensors that cause a pulse to arrive back from the sensor array at a time later than expected. Noise is also be contributed by the optical source which may not be pulsed in an ideal manner so that there is a finite level of optical power between successive pulses.
Bragg grating sensor systems often require a very high dynamic range of eighty to a hundred and twenty decibels. Therefore any small sources of noise can be significant. To optimize the performance of the system it is necessary to perform the signal gating in as short a time period as possible. This allows the system to reject a large portion of the noise that does not return at the same time as a sensor pulse. With the method of gating used previously in the art, the performance of the system is limited. An electronic circuit performs the gating action after an optical detector has detected the optical signal. Therefore the electronic circuit must be operated at the speed of arrival of the optical pulses. It is difficult to operate electronic circuits at very high speed and still maintain very high signal fidelity due to noise and distortion. Since the gating is done after the optical signal is detected, the wavelength measurement on the signals must be done before the gating. Therefore any noise or distortions in the gating process will create errors in the sensor signal. Furthermore, the limited operation of this gating method will reduce the spatial resolution of the sensor system since the pulses from the sensor array must be spaced far apart in time.
It would therefore be very advantageous to provide a method and apparatus for time division optical multiplexing multiple serial Bragg gratings in optical fibers which reduces noise associated with the gating process and allows for very fast gating times.

Method and device for time domain demultiplexing of serial fiber Bragg grating sensor arrays


The present invention provides a method and apparatus for detecting a continuous current of a switching current. A current signal is produced in response to a switching current of the magnetic device. By sampling the waveform of the current signal in response to the enabling of a switching signal, a first current signal and a second current signal are generated. A continuous current signal is produced according to the first current signal and the second current signal. The continuous current signal is corrected to the continuous current of the switching current.

1. Field of the Invention
The present invention relates to switching control circuit, and more particularly, to a switching control circuit of a magnetic device.
2. Description of Related Art
Switching control circuits have been widely used in power conversion. FIG. 1 shows a power converter including a controller 50 for generating a switching signal SW to regulate the output of the power converter in response to a feedback signal VFB. The switching signal SW drives a power transistor 20 for switching a transformer 10. The transformer 10 is connected to an input voltage VIN of the power converter. The energy of the transformer 10 is transferred to the output voltage VO of the power converter through a rectifier 40 and a capacitor 45. A resistor RS is connected in series with the power transistor 20 to generate a current signal VI in response to a switching current IP of the transformer 10. The current signal VI is coupled to the controller 50 to control the power converter. The power converter may be operated in a discontinuous current mode (DCM) when the magnetic device such as the transformer 10 is fully discharged before the start of the switching cycle. If the switching signal SW is enabled before the transformer 10 is fully discharged, the power converter may be operated in a continuous current mode (CCM). A continuous current may be retained in the transformer when the power converter operated in the CCM. FIG. 2 shows a CCM waveform of the switching current IP, in which the continuous current IA represents the energy stored in the transformer 10. A current IB is the energy that is further charged into the transformer 10 during the on time TON of this switching cycle. The continuous current IA stands for a major energy transfer of the transformer 10. The object of the present invention is to develop a method and apparatus to measure the continuous current IA of the switching current IP.

Method and apparatus for detecting switching current of magnetic device operated in continuous current mode


A recording paper containing pulp fibers and filler as main components and containing at least a heterocyclic carboxylic acid and a water-soluble polymer in the surface of the recording paper, wherein the surface contains at least one kind of cationic substance selected from the group consisting of a cationic organic molecule and a metal salt containing a metal cation of valency two or greater.

1. Field of the Invention
The present invention relates to a recording paper and an image recording method thereof. In particular, the invention relates to a recording paper using so-called plain paper without coating layers containing substantial quantity of pigment on either surface thereof, and an image recording method for ink-jet printing and electrophotographic printing using the same.
2. Description of the Related Art
An image forming machine using an ink-jet printing method has characteristics such as: ease of coloring, low energy consumption, low noise generation during recording; and the ability to suppress production costs to low levels. Due to such advantages, image forming machines using ink-jet printing methods have become widely used in offices in recent years, with increases in the number of machines which use ink-jet printing methods combined with electrophotographic image recording machines such as laser printers and copy machines.
Recording media (recording paper) such as so-called plain paper, coated paper and glossy paper, white film, and transparent film are used in image forming with ink-jet printing methods. Particularly when an image forming machine using ink-jet printing methods is employed in an image forming machine of an electrophotographic printing method, such as a laser printer or copier in an office or the like, printing is conducted most often on plain paper. Among these machines most use plain paper, on which an image can be formed easily, which is readily available and at a low cost.
Therefore, enhancing the suitability for recording of plain paper image forming with ink-jet printing methods is extremely important. However, there have been the following problems when printing is conducted on plain paper in conventional image forming with ink-jet printing methods.
(1) A so-called feathering phenomenon occurs whereby ink flows out along fibers of plain paper. Feathering significantly deteriorates image quality, particularly the quality of printed characters/letters.
(2) So-called plain paper usually contains a sizing agent on the surface for making the surface water-repellent. Consequently, absorption of ink is delayed, causing so-called inter-color bleeding (ICB) at portions where different colors contact with each other.
(3) Since absorption of ink is delayed due to the water repelling properties of plain paper surfaces, faces which contact with printed surfaces become dirty when printed documents are stacked.
(4) Since colorants in ink hardly stay on the surface of plain paper, the coloring nature of color ink is inadequate.
(5) Since colorants in inks permeate into plain paper, printed images can be seen through from the back of plain paper—rendering double-sided printing impossible.
Ink-jet printers have attempted to produce high printing speed, comparable to that of laser printers, in accordance with an expanded market for ink-jet printer in the office. However it has been very difficult to attain improved permeability (dryability) and image quality whilst also the ability to carry out double-sided printing.
In the light of these problems, methods of promoting coagulation and sedimentation of components contained in the ink by surface treating pape with cationic substances such as cation polymers, polyvalent metallic salts or the like are proposed. Of these methods, a method of adding a substance (usualy a polymer) to inks which reacts with a cationic substance applied to the surface of paper, thereby enhancing the viscosity of the ink applied thereto, is particularly useful for improving image quality. This is because the non-uniform spread-out rates of colorants contained in ink when ink is applied to paper surfaces can be controlled when high viscosity is obtained.
However, when the acid value of the polymer described above is large (equivalent to the amount of the anionic hydrophilic groups reacting with the cationic substance), the viscosity of the ink is raised excessively, the jetting performance of the ink jetted out from the recording head, or permeability of the ink into the paper may be damaged. On the other hand, when the acid value is small, the polymer is in a state of emulsion, and the increase in the viscosity of the ink is suppressed. Thus the jetting performance can be secured. However, since the number of reacting groups contributing to the acid value is few in the polymer, the reactivity with the cationic substance contained on the surface of the paper becomes low, and large improvements in image quality can not then be obtained.
On the other hand, in parallel to the improvements of ink composition described above, diversification in colorants has progressed in recent years, and, in addition to dyes widely used conventionally, pigments are being used more and more often in color inks. Thereby, situations where ink-jet printers using dye based inks and ink-jet printers using pigment based inks live together in the same office has come about.
When colorants are dyes and when colorants are pigments, generally the following respective methods are used effectively for raising image quality with recording papers designed for ink-jet printing.
When the colorant is a dye, a method is mentioned whereby the dye is reacted with a cationic substance contained on the surface of the paper, forming an insoluble dye complex, which is then physically trapped on the surface of the paper, is mentioned.
When the colorant is a pigment, a method is mentioned whereby a low molecule cationic substance contained on the surface of the paper rapidly elutes into the ink applied to the surface of the paper. This has the effect of rapidly raising the the concentration of electrolytes in the ink, coagulating the pigment as a pigmented colloid and fixing the pigment on the surface of the paper.
In order to obtain the full improvement effects in image quality with both dyes and pigments, it is necessary to include on the surface of the paper large amounts of both low molecule cations having fast elution, and polymers having good low molecule fixing performance.
However, a paper containing large amounts of substances having strong ionicity on the surface may overreact to surrounding environmental changes, and the electric resistivity of the paper may be reduced. Therefore, when such paper is used for image formation using electrophotographic printing methods in laser printers and the copy machines or the like, the paper has a bad influence on the transferability of toner. This means that such paper is not suitable for image formation using electrophotographic printing methods. Therefore, it is necessary to use a different paper for each printer having different image forming methods in the office (for example, see Japanese Patent Application Laid-Open (JP-A) Nos. 10-166713, 7-257017, 8-216498 and 10-100531).
When ink containing a component which reacts with cationic substances contained on the surface of the paper, to become insoluble, is used for image formation, when the ink is applied to the surface of the paper, huge coagulates containing the colorant are formed. This gives a significant improvement in image quality. However, in practice, components having sufficient reactivity to cationic substances are restricted to polymers having significant numbers of hydrophilic groups. Even if ink containing these components is used for image formation, when the ink is applied to the surface of the paper, the viscosity of the ink is increased. Thereby, not only fast drying properties needed for high-speed printing, but also ink jetting performance may suffer (for example, see Japanese Patent Application Laid-Open (JP-A) Nos. 9-176995 and 2002-96547).

Recording paper and image recording method


A method of performing context inference is described. The method includes collecting ambient light at a spectrometer sensor integrated in a portable device, characterizing the collected light to obtain optical information, comparing the optical information to optical data predetermined to match one or more contexts, inferring at least one characteristic of a specific context based on the comparison, and determining a probability that the portable device is in the specific context.

Users of smartphones and other mobile devices often want to know about their context or surroundings. For example, a user may want to determine their location, whether the immediate environment includes natural or artificial light, or whether a particular device, such as a TV, radio, or microwave is nearby. In addition, smartphone applications can leverage contextual information to provide additional services, or enhanced services, to the user. A smartphone operating system itself can use contextual information to better manage system resources. For example, if the environment around the device is relatively static, then some operations can be delayed, saving precious battery power.
Mobile devices collect optical information through sensors, such as an ALS (ambient light sensor) and a camera, which can include an RGB (red, green, blue) sensor. The ALS sensor senses surrounding light levels and typically adjusts the brightness of a display, e.g., a screen. Thus, an ALS sensor does not provide a user with much information regarding his surroundings. A camera, on the other hand, captures light information to produce an image, but uses a lot of power. Thus, it is not currently practical to have a camera always running to determine the environment of a user.
Accordingly, a need exists for a simple and low power sensor to determine user context.


An image heating apparatus for heating an image formed on a recording material has a heater having a heat generating resistor, an electrically conductive substrate, an intermediate insulating layer formed between the resistor and the substrate and two surface insulating layers provided on substantially entire areas of both surfaces of the substrate. The surface insulating layer on that surface side of the substrate which is opposed to the recording material is higher in heat conductivity than the surface insulating layer on the opposite surface side.

1. Field of the Invention
The invention relates to a heater having an electrically conductive substrate and an image heating apparatus such as a heating and fixing apparatus carried on an image forming apparatus such as a copier or a printer.
2. Description of Related Art
In an image output apparatus such as a copier, a printer or a facsimile apparatus using a suitable image forming process such as electrophotographic, electrostatic recording or magnetic recording, a heating apparatus of the heat roller type has heretofore been used as a fixing apparatus for fixing a toner image formed and borne on a recording material by a transferring method or a direct method on the surface of the recording material.
The heating apparatus of the heat roller type basically comprises a metallic roller provided with a heater therein, and a pressure roller having elasticity and brought into pressure contact therewith, and a recording material as a member to be heated is introduced into a fixing nip part (pressure contact nip part) formed by the pair of rollers and is nipped and conveyed by the fixing nip part to thereby heat and pressurize a toner image and fix it on the recording material.
In such a heating apparatus of the heat roller type, however, the heat capacity of the roller is great and therefore, much time has been required to raise the surface of the roller to a fixing temperature. This also has led to the problem that to execute the image outputting operation quickly, the surface of the roller must be controlled to a certain degree of temperature even when the apparatus is not used.
So, heating apparatus devised to solve these problems include heating apparatuses of the film heating type disclosed, for example, in Japanese Patent Application Laid-Open No. 63-313182, Japanese Patent Application Laid-Open No. 2-157878, etc. filed by the applicant.
Such heating apparatus of the film heating type usually comprises a thin heat-resistant film, a heating member (hereinafter referred to as the heater) fixedly supported and disposed on one surface side of the film, and a pressure member disposed on the other surface side of the film in opposed relationship with the heater for bringing a member to be heated into close contact with the heater with the film interposed therebetween.
The member to be heated, i.e., in an image heating apparatus, a recording material having a toner image formed and borne thereon, is introduced and passed between the film and the pressure member in a pressure contact nip part formed by the pressure contact between the heater and the pressure member with the film interposed therebetween, whereby the visible image bearing surface of the recording material is heated by the heater through the film, and heat energy is imparted to the unfixed image, and the toner is softened and fused, whereby the heating and fixing of the image are done.
The film heating type is excellent for its quick starting property, and can greatly curtail the electric power consumption during the standby state, and can constitute a heating apparatus of the on-demand type.
Heretofore, in a fixing apparatus adopting such a film heating type, for example, as the heater, use has often been made of a ceramic substrate such as alumina as a substrate as in a ceramic heater, but this has posed the problems of the fragility or high cost of ceramics, and the unsuitability of ceramics for bending.
So, in Japanese Patent Application Laid-Open No. 9-244442 and Japanese Patent Application Laid-Open No. 10-275671, there is proposed a heating member (a conductive substrate heater, hereinafter referred to as the metallic heater) comprising a substrate given insulating property equal to that of a conventional ceramic substrate by forming an insulating layer on a metal material, and a heat generating resistance pattern, an electrically conducting pattern and an uppermost insulating sliding layer formed thereon.
By using a conductive substrate such as a metallic substrate high in heat conductivity as the substrate material of the heater, as described above, the temperature of the heater can be uniformalized over the entire area thereof and particularly, the temperature fall in the opposite end portions thereof can be prevented, whereby there can be formed a good image free of the unevenness of image such as uneven fixing, uneven luster or offset liable to occur over the length of a recording material. The temperature rise speed of the heater can also be improved, and it becomes possible to enhance the quick starting property. Further, as compared with ceramics or the like, the rupture strength itself of the metallic substrate is very high and therefore, there is no rupture of the substrate against heat stress or the like occurring during the sudden temperature rise of the heater, and the arising of a problem such as the breakage of the substrate in the manufacturing process can be suppressed, and it becomes possible to enhance productivity.
Also, to raise the temperature more quickly as the heater, it is necessary to efficiently give the heat of the heater to a member to be heated, and as a characteristic necessary for the heater, it is desirable to improve the heat conduction of the surface side of the heater (that surface side opposed to the member to be heated, or the paper passing surface side, hereinafter the same) and efficiently impart heat to the film and the recording material and at the same time, have on the back side of the heater (the surface side opposite to the surface side opposed to the member to be heated, or the non-paper passing surface side, hereinafter the same) such an adiabatic effect as will suppress the escape of heat to a heater supporting member or the like to the utmost.
The present invention has been made in view of the above-noted problems and an object thereof is to provide a heater which is high in strength and of which the adiabatic property of one surface is high and an image heating apparatus using the heater.
Another object of the present invention is to provide an image heating apparatus comprising a heater including a heat generating resistor, an electrically conductive substrate, an intermediate insulating layer formed between said resistor and said substrate and two surface insulating layers provided respectively on substantially entire areas of both surfaces of the two substrates, wherein the surface insulating layer on that surface side of the substrate which is opposed to a recording material is higher in heat conductivity than the surface insulating layer on the opposite surface side.
Still another object of the present invention is to provide a heater comprising:
a heat generating resistor;
an electrically conductive substrate; and
surface insulating layers provided on both surfaces of the substrate;
wherein the surface insulating layers differ in heat conductivity from each other.
Yet still another object of the present invention is to provide an image heating apparatus comprising a heater including a heat generating resistor, an electrically conductive substrate and surface insulating layers provided on both surfaces of the substrate, wherein the surface insulating layer on the side opposite to that surface of the substrate which is opposed to a recording material is greater in surface roughness than the surface insulating layer on the opposed surface side.
A further object of the present invention is to provide a heater comprising:
a heat generating resistor;
an electrically conductive substrate; and
surface insulating layers provided on both surfaces of the substrate;
wherein the surface insulating layers differ in surface roughness from each other.
Still a further object of the present invention is to provide an image heating apparatus comprising a heater including a heat generating resistor, an electrically conductive substrate, surface insulating layers provided on both surfaces of the substrate, and a temperature detecting element for detecting the temperature of the heater, wherein that area of the heater to which the temperature detecting element is opposed is higher in heat conductivity than the peripheral area thereof.
Yet still a further object of the present invention is to provide a heater comprising:
a heat generating resistor;
an electrically conductive substrate; and
surface insulating layers provided on both surfaces of the substrate,
wherein one surface of the heater has in a lengthwise portion thereof an area higher in heat conductivity than the peripheral area thereof.
Further objects of the present invention will become apparent from the following detailed description when read with reference to the accompanying drawings.

Heater having electrically conductive substrate and image heating apparatus with heater


A silicon nitride sintered body comprised of 1.5 to 3.0% by weight of Y.sub.2 O.sub.3, 0.1 to 1.0% by weight of Al.sub.2 O.sub.3 and 96 to 98.4% by weight of Si.sub.3 N.sub.4 wherein the Y.sub.2 O.sub.3 /Al.sub.2 O.sub.3 weight ratio is at least 2.5, and having a density of at least 3.0 g/cm.sup.3, exhibits a high oxidation resistance and a high strength at a high temperature. This silicon nitride sintered body is prepared by sintering a powdery mixture consisting essentially of 1.5 to 3.0% by weight of Y.sub.2 O.sub.3 powder, 0.1 to 1.0% by weight of Al.sub.2 O.sub.3 powder, and 96 to 98.4% by weight of Si.sub.3 N.sub.4 powder, the Y.sub.2 O.sub.3 /Al.sub.2 O.sub.3 weight ratio being at least 2.5, the oxygen content in the Si.sub.3 N.sub.4 powder being less than 2.0% by weight and the total metallic impurity content in the Si.sub.3 N.sub.4 being less than 200 ppm, at a temperature of 1,850.degree. to 2,000.degree. C. in a non-oxidizing atmosphere.

(1) Field of the Invention
The present invention relates to a silicon nitride sintered body having a high oxidation resistance and a high strength at a high temperature, and a process for the preparation of this silicon nitride sintered body.
(2) Description of the Related Art
Since a silicon nitride sintered body has a high strength, a high heat resistance, a high thermal shock resistance, a high abrasion resistance, and a high oxidation resistance, it is probable that this silicon nitride sintered body will be utilized as structural ceramics for gas turbine members, steel-making high-temperature rolls and the like where severe high-temperature conditions apply. Since it is difficult to sinter a material composed solely of silicon nitride, densification is attempted by adding various sintering aids. The sintering aids, however, form a glassy phase having a low melting point in the grain boundary of silicon nitride and the high-temperature strength is often reduced by the presence of this glassy phase. To eliminate this disadvantage, the following methods have heretofore been proposed.
(1) The addition of an oxide of a rare earth element, such as yttrium oxide.
(2) The addition of an oxide of a rare earth element, such as yttrium oxide, and an oxide such as aluminum oxide (see, for example, Japanese Examined Patent Publication No. 49-21,091).
(3) The addition of yttrium oxide, aluminum oxide and aluminum nitride, and after sintering, the precipitation of a second phase of yttrium aluminum garnet (YAG) or the like by a heat treatment (Japanese Unexamined Patent Publication No. 58-55,375).
However, these methods have the following problems from the practical viewpoint.
(1) According to the method in which yttrium oxide is added, the grain boundary of silicon nitride is bonded through, for example, a highly viscous glass or a crystalline composition such as Si.sub.3 N.sub.4 .cndot.Y.sub.2 O.sub.3 and, therefore, the reduction of the high-temperature strength and high-temperature creep resistance is small, but the high-temperature strength is still too low. Moreover, since sintering is difficult, pressureless sintering cannot be employed.
(2) According to the method in which yttrium oxide and aluminum oxide are added, sintering is promoted and a sintered body having a high density and a high strength can be obtained even by pressureless sintering. However, the reduction of the high-temperature strength is still large, and unless a special sintering method such as a hot-press method is adopted after an operation such as a crystallization treatment, a dense sintered having an excellent high-temperature strength cannot be obtained.
(3) According to the method in which a second phase is precipitated by a heat treatment after sintering, the reduction of the high-temperature strength is moderated, but the precipitation of the second phase causes a change of the volume and, therefore, the thermal shock resistance of the sintered body is lowered.
Moreover, in the sintered bodies obtained according to these methods, the temperature at which the oxidation resistance is effected is about 1,200.degree. C. at highest, and therefore, such sintered bodies cannot be applied at higher temperatures, and accordingly, silicon carbide is mainly used as the applicable ceramic material at temperatures higher than about 1,300.degree. C.

Silicon nitride sintered body and process for preparation thereof


A portable and personal sauna that provides an inexpensive and easy to operate system, which provides steam with low operating costs. The portable sauna has an electric steamer with a timer, a safety thermostat, and a plate for containing herbs. When steam passes through the herb plate, the herbal steam can provide some healthy benefits to users. The preferable and safest place for the steamer is outside of the tub/shower area, where a flexible tube is used to guide the steam inside the tub/shower area.

This invention relates to a personal sauna, in particular to a personal sauna used in combination with a bathtub or shower enclosure.
Sauna is a great way for relaxation and enjoyment. However, most apartments and houses do not have adequate room for a permanent or capsule-type sauna. Known sauna capsules are expensive, cumbersome to install, and take up a great deal of space. Furthermore, such sauna systems gives users a claustrophobic feeling of being in a small and confined area.
Accordingly, it is an object of this invention to provide a personal sauna system overcoming the shortcoming of the prior art.
It is a further object of this invention to provide a personal steam bath that does not occupy a great deal of space and is easy to store and may be used with a shower or bathtub enclosure.
The present invention converts a bathtub or shower enclosure into a low cost sauna. The assembly uses a plastic retractable cover member above the shower to close off the tub/shower area while the steamer is being used. After using the enclosed area as a sauna, the retractable cover member is moved and the sauna can be converted back into a tub/shower enclosure. Conversion time takes only seconds, and this sauna needs only minimal storage space.
The present invention utilizes an electric steamer, which is preferably placed outside of the shower or bathtub enclosure. A flexible hose extending from one end of the steamer is inserted inside the enclosure to provide steam. Herbs, such as lavender and camellia can be placed on an herb plate or tray for an enjoyable, healthy, and relaxing sauna experience. The personal sauna uses electricity or gas to bring water to the boiling temperature to create steam and further utilizes a timer and thermostat to safely control the operation of the sauna.

Personal sauna in shower or in bathtub enclosure


A wireless communication system broadcasts a control signal at a first frequency band from a base station and allocates additional frequency band(s) for transmitting data via terminal(s). A control signal at the first frequency band indicates the location of the additional frequency band(s) and is not transmitted over the additional frequency band(s). Wireless data transmission is simultaneously performed over the first frequency band and the additional frequency band(s). Each terminal receives the control signal, which is used in time-synchronizing frames between the wireless data transmission at the first frequency band and the wireless data transmission at the additional frequency band(s). The control signal also includes control data for managing wireless data transmission between the base station and the terminal(s) at the first frequency band, and is utilized instead of a control signal at the additional frequency band(s).

1. Technical Field
The present invention relates to a wireless communication system comprised of a base station and mobile stations, particularly to an improvement relating to inter-mobile station direct communication in a wireless communication system based on a TDMA (Time Division Multiple Access) system.
2. Background Art
A wireless communication system is comprised of a base station for giving notices of allocations of bands (time regions for communications) and a plurality of mobile stations based on the TDMA system (in which different time regions are allocated to the mobile stations at the same frequency for carrying out communication). For such a system, a PHS inter-mobile station direct communication system in accordance with RCR STD-28 (second-generation cordless telephone system standard, version 1) of ARIB (Association of Radio Industries and Businesses) has been proposed as a method of carrying out inter-mobile station direct communication at a frequency other than that used by the base station. Improvements of the system are disclosed in JP Patent Publication (Kokai) Nos. 11-122663 A1 (1999) and 11-341564 A1 (1999), for example.
FIG. 13 shows an example of the frame structure in the TDMA wireless communication system.
As shown in FIG. 13(a), a length of time in which the same frequency is used for communication is divided into frames 1 at predetermined time intervals. In each frame (at predetermined periods), the base station transmits control information 2 to all of the mobile stations in a wireless LAN area created by the base station. The control information 2 includes information allowing the multiple mobile stations to be synchronized with the base station, and information indicating the band (time region) within the frame allocated to each mobile station.
The frame is divided into the time regions of DOWN-LINK 3 for the transmission of data from the base station to the mobile stations and UP-LINK 4 for the transmission of data from the mobile stations to the base station. In each time region, each mobile station is allocated a band 5 (band A) and a band 6 (band B), as shown in FIG. 13(b), such that the base station and the mobile stations can communicate with one another bi-directionally.
The control information 2 will be hereafter described by referring to FIG. 13(c).
Generally, in the physical layer of wireless systems, a digital signal comprised of a preamble 200 for broadcast and a data payload 201 (data payload 1, . . . , data payload N), which is information data for transmission, is converted into an electric signal. The preamble 200 located at the head identifies the signal received from a wireless interface. Particularly, the preamble 200 for broadcast that is attached when the base station transmits broadcast information into a wireless cell functions as a synchronization signal with which a mobile station in the wireless cell attempts to achieve synchronization with the base station. Further, the control information 2 includes such control information as frame structure information and band allocation information.
FIG. 14 shows a block diagram of an example of the configuration of a wireless LAN based on the above-described wireless communication system.
In FIG. 14, numeral 7 designates a WAN (Wide Area Network), and numeral 8 designates a wireless LAN (Local Area Network). The wireless LAN 8 is comprised of a plurality of mobile stations 11-13 and a base station 10. The base station 10 is either connected to a central control unit 9 for the central control of band allocations, or is equipped with the central control unit 9 inside. The wireless LAN 8 is connected to the WAN 7 via the base station 10.
The mobile stations 11 to 13 carry out a base station-mobile station communication according to the band allocation information notified by the base station 10. The communication paths are indicated as communication paths 14-16. The communication path for direct communication between a mobile station 11 (mobile station <1>) and a mobile station 12 (mobile station <2>) is indicated by a communication path 17.
When the mobile station 11 (mobile station <1>) transmits data to the mobile station 12 (mobile station <2>), if the normal base station-mobile station communication is employed, the same data would have to be transmitted twice via the communication paths 14 and 15 shown in FIG. 14, which is inefficient. Thus, it is necessary to use a method for carrying out inter-mobile station direct communication by which data is directly transmitted between the mobile stations via the communication path 17 without the intervention of the base station 10.
FIG. 15 shows an example of the frame structure for inter-mobile station direct communication in a conventional wireless communication system.
In the example of FIG. 15, inter-mobile station direct communication is conducted at a frequency different from the one used by the base station 10. One of the mobile stations that carry out inter-mobile station direct communication transmits control information 19 at the frequency for inter-mobile station direct communication. This frequency is different from the frequency at which frame synchronization is achieved and communications are carried out according to the control information 18 transmitted by the base station. The mobile stations that carry out the inter-mobile station direct communication are provided with a base-station function for synchronizing their frames and allocating bands.
Other examples of conventional techniques for carrying out inter-mobile station direct communication include: a wireless LAN system and a PDC (Personal Digital Cellular) portable telephone employing the CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) system according to the ISO/IEC (International Organization for Standardization/International Electrotechnical Commission) 8802-11 or the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standards; HiperLAN according to the ETSI (European Telecommunications Standards Institute), which is a 3.5-generation system transitioning into a 4th-generation system to be standardized around the year 2010 following PHS (Personal Handy-phone System) and the W-CDMA (Wideband Code Division Multiple Access); and the MMAC (Multimedia Mobile Access Communication System) wireless system according to the ARIB (Association of Radio Industries and Businesses).
The IEEE802.11 and the HiperLAN will be briefly described below, although they do not have direct relevance to the present invention in that the former is not a centrally controlled wireless system comprising a central control unit for centrally controlling band allocations, and that the latter is a system that employs the same frequency as that for base station-mobile station communication.
FIG. 16 shows an example of communication according to the IEEE802.11 system.
In FIG. 16, among mobile stations 1 to 4 in a wireless LAN area 20, when a mobile station <1> wishes to send information to a mobile station <2>, the mobile station <1> broadcasts an RTS (Request to Send) signal 21 and 24. Each mobile station analyzes the RTS signal. When it is not an information transmission request directed to a particular mobile station, the mobile station stands by. When the RTS signal is directed to a particular mobile station, the mobile station (mobile station <2>) transmits a CTS (Clear to Send) signal 22 and 25 to indicate that it is ready to receive. In response, the mobile station <1> transmits information via a MAC signal 23 and 26 to the mobile station <2>. During these processes, the other mobile stations refrain from transmission for a certain time period to avoid collision of transmission signals.
FIG. 17 shows an example of the frame structure in the HiperLAN system. Parts or elements similar to those shown in FIG. 13 are designated by similar references.
In the HiperLAN system, a band 28 is provided in a TDMA frame 27 for carrying out inter-mobile station direct communication. In this band 28, the base station ceases transmission to allow the mobile stations to transmit to each other, thus allowing base station-mobile station communication and inter-mobile station direct communication to take place on a single frequency.
In a conventional wireless communication system, the frames for inter-mobile station direct communication and those for base station-mobile station communication are not synchronized, as shown in FIG. 15. Thus, in order to obtain control information for synchronizing the respective frames, the communication modes are switched. This is a process in which a mobile station terminates its connection with the base station for base station-mobile station communication and then sets up a connection with the mobile station that has the base-station function for carrying out inter-mobile station direct communication. An improved method of obtaining broadcast information from the base station is proposed by JP Patent Publication (Kokai) No. 11-122663 A1 (1999), for example, in which the switching is carried out intermittently.
However, the apparatus disclosed in the above publication has the problem that the mobile station 11 (mobile station <1>) cannot carry out data communication with the mobile station 12 (mobile station <2>) and the base station 10 simultaneously, as shown in FIG. 14. In recent communication systems, there is an ongoing shift from voice communication by telephone to data communication. Thus, the above problem means that, in the context of building a wireless LAN, the mobile stations are intermittently cut off from the network, creating further problems. For example, the base station may not be able to transmit data received from a connected WAN (such as the Internet) to a destination mobile station in the wireless LAN, or the base station may not even recognize the presence of the mobile station due to the absence of connection therewith.
The above discussion is based on the assumption of creating, for example, a household wireless LAN (home network) comprised of a gateway unit including a base station connected to the Internet outside, and mobile stations including household information appliances (such as a refrigerator, microwave oven, television, video server, or set-top box, for example). In this case, it would be problematic if the external network could not send video information to the video server when the video server is wirelessly transmitting video information to the television, or if, when an air conditioner should be externally operated, the presence of the air conditioner on the network could not be confirmed due to the termination of its connection to the base station.
Further, in order to realize inter-mobile station direct communication, there is the additional problem of having to add the base-station function to one of the mobile stations that is to act as the base station.
It is an object of the invention to provide an efficient wireless communication system that allows for base station-mobile station communication even when inter-mobile station direct communication is carried out at a frequency other than that of the base station, which can reduce the burden on the mobile stations by having the base station control inter-mobile station direct communication, and which allows a plurality of frequencies to be simultaneously used by a single base station.


In order to obtain good efficiency of a pulse combustion apparatus, an ignition plug is protected to extend its life span by way of controlling the rotation of the ground electrode at the wall face of a combustion chamber wherein 100.degree..about.200.degree. C. may be reduced from a conventional temperature of 900.degree. C. at the ground electrode in the ignition plug.

1. Field of the Invention
This invention relates to a pulse combustion apparatus in which pulsating explosive combustions occur repeatedly and continuously. A pulse combustion apparatus performs repeatedly explosive combustions in a certain cycle by making use of self-ignition and natural suction of air for combustion at the time of regular combustion, and wherein combustion heat is used for cooking devices and etc.
2. Description of the Prior Art
One example of a combustion chamber of this pulse combustion apparatus is shown in FIG. 4. A combustion chamber 1 in which explosive combustions are carried on is generally formed and sectioned by a wall 3 having a curved face similar to that of a snail with a fundamental curvature owing to the characterization of combustion and so on. An ignition plug 10 is set and inserted into the curved wall 3 spirally by the screw part 13. Also, 7 in the Figure represents a tail pipe for the discharge of combustion exhaust.

Plug mount structure of a pulse combustion apparatus


In one embodiment, a contact center is provided that includes:    (a) a work item queue 208, 250 comprising an intra-enterprise contact associated with at least first and second internal endpoints of an enterprise; and    (b) a selector operable to select and assign a work item to an agent. In selecting the work item, the selector considers both a customer contact and the intra-enterprise contact. The intra-enterprise contact, for example, can be a training notification.

Contact centers, such as Automatic Call Distribution or ACD systems, are employed by many enterprises to service customer contacts. A typical contact center includes a switch and/or server to receive and route incoming packet-switched and/or circuit-switched interactions and one or more resources, such as human agents and automated resources (e.g., Interactive Voice Response (IVR) units), to service the incoming customer contacts.
The ACD workflow routing engine in the contact center directs contacts to various agents based on sophisticated algorithms and a number of predetermined criteria. Typically the criteria for servicing the contact, from the moment the contact center becomes aware of the contact until the contact is connected to an agent, are customer-specifiable (i.e., programmable by the operator or manager of the contact center), via a capability called vectoring for calls, or through complex programmable workflows that determine the right or "optimal" agent based on various predetermined criteria. Normally, predetermined criteria include agent skills, interaction requirements, media type and availability of an agent, expected contact wait time, customer identity, customer class membership, relatedness to other customer communications (e.g., threads), previous interaction history, etc. ACDs commonly use skills-based routing in which the ACD identifies all predefined customer interaction-handling skills of the agent and delivers to the agent the contact that matches the agent's highest-priority skill. If the contact is document-based (e.g., email, fax, Short Message Service or SMS message, instant message, etc.), the matching can also be done based on analyzing the contact's content via natural language processing of the content to determine the topic and then routing the contact to an agent deemed the Subject Matter Expert or SME for that topic. Commonly, the only conditions that result in a customer contact not being delivered are that there are no available agents (in which case the contact is queued to be routed to the next available agent) or that there are no customer contacts to be delivered.
In contact centers, there is frequently a need to provide intra-enterprise contacts, such as agent-to-agent contacts and supervisor-to-agent contacts, to agents in a manner that does not interrupt the servicing of customer contacts. The current approaches for delivering such contacts, and their drawbacks, are best illustrated by supervisor-to-agent contacts provided to agents as part of a training program to improve agent performance.
Currently, training programs involve monitoring agent interactions in the contact center, collecting and analyzing the events against a norm (or desired interaction), and delivering a visual indication of the process violation or improvement to a supervisor or agent against future state interactions which may meet similar criteria. The remedy for this situation may be an offline coaching session or a training module notification delivered during lulls in contact demand.
Current approaches do not predictively assess the impact of how to balance whether a resource should receive a customer contact or an agent training notification against the total work occurring in real time in the contact center. Current approaches depend on human resources to coach the agent on their process violations once they occur and are aggregated, perhaps taking the agent offline, or "interrupting" current call processing at the expense of real-time service goals, or waiting for scheduled or unscheduled "lulls" in customer contacts.
Current approaches do not anticipate work that is "about to occur", or "is occurring", which may be at risk for similar inefficient service or lack of relevant information. In other words, the approaches aggregate only work that has already occurred.
Current approaches do not assess the impact of imparting additional information to particular call types against total service level commitment occurring in real time in the contact center. Such information is relevant when an impending contact type, that has been previously serviced poorly, is identified in the work queue and when a contact is received that could benefit from a process improvement, such as imparting additional information or insights to the customer (such as additional offers).
Finally, current approaches do not deliver notifications independent of any impending contact.

Method and apparatus for the automated delivery of notifications to contacts based on predicted work prioritization


A vehicle seat console has at least one vehicle-side guide element and at least one seat-side guide element that is arranged parallel to the vehicle-side guide element. At least one longitudinal adjustment device that is acted upon by a drive device is designed to bring about a relative adjustment between the vehicle-side guide element and the seat-side guide element. The longitudinal adjustment device is provided with a toothed rack and a gearwheel that is in meshing engagement with the toothed rack. The teeth of the gearwheel and/or the teeth of at least one section of the toothed rack are made of materials of different shear strength.

The invention relates to a vehicle seat console. The invention also relates to a vehicle seat having such a vehicle seat console and to a motor vehicle having at least one such vehicle seat.
Belt systems and airbags are motor-vehicle passenger-protection systems which have been recognized for decades. They reduce the loading to which the passengers in a vehicle are subjected, in the event of a vehicle collision, usually only when said passengers are in defined, upright sitting positions. However, particularly in the case of fully automated driving, lying positions are becoming more and more important, and therefore adequate protection for passengers in such lying positions also has to be ensured. However, in the event of a vehicle collision, the known passenger-protection systems cannot sufficiently reduce the loading to which the passengers are subjected when they are in a lying or semi-lying position. There is therefore a need for the passenger-protection systems to be further developed so that, in the event of a vehicle collision, the acceleration of a passenger's body, even when the passenger is in a lying or semi-lying position, is limited to a defined level.
It is the object of the present invention to provide a vehicle seat console of the generic type which is designed so that, in the event of a vehicle collision, it sufficiently limits the loading to which the body of a person sitting on the vehicle seat is subjected, even if this person is in a lying or semi-lying position.
A vehicle seat console having at least one vehicle-mounted guide element and at least one seat-mounted guide element, which is arranged parallel to the vehicle-mounted guide element, and at least one longitudinal-adjustment device, which is activated by a drive device and is configured to effect relative adjustment between the vehicle-mounted guide element and the seat-mounted guide element, wherein the longitudinal-adjustment device has a rack and a gearwheel, which is in meshing engagement with the rack, is distinguished, according to the invention, in that the teeth of the gearwheel and/or the teeth of at least one portion of the rack consist of materials with different levels of shear strength.
The longitudinal adjustment of the vehicle seat takes place, in a manner known per se, by way of an electrically driven, or drivable, gearwheel, which is mounted in a rotatable manner on the vehicle seat or on the upper rail and meshes with the teeth of the rack, and rolls on the rack, as a result of which the vehicle seat is adjusted in the longitudinal direction of the vehicle. This apparatus therefore mounts the vehicle seat in a movable manner relative to the vehicle structure. In the event of a collision, the vehicle seat occupied by the passenger, on account of its mass inertia, tries to carry on moving counter to the collision force acting on the vehicle structure. However, on account of its inherent self-arresting action, the gearwheel is not capable of allowing relative movement between the vehicle-structure-mounted lower rail and the seat-mounted upper rail.
The selection of material according to the invention for the teeth of the gearwheel, and at least some of the teeth of the rack, allows the teeth made of the material with the lower level of shear strength to fail, and relative movement between the upper rail and the lower rail, that is to say between the vehicle seat and the vehicle structure, can take place. The failing teeth therefore free an amount of displacement travel at a defined force level. This is therefore achieved via the combination of gearwheel and rack made of materials with different levels of shear strength.
By virtue of the provision of the teeth made of the material with the lower level of shear strength in the pairing between the gearwheel and rack, the core of the invention is therefore that of specifically forming a weak-point region in which—in a manner similar to a predetermined breaking point—desired material failure occurs, that is to say a material-failure region is created, in the event of overloading. The collision acceleration which acts on the vehicle structure in the event of a vehicle collision gives rise, in the vehicle seat, to an oppositely directed acceleration, which in turn generates a force which acts on the tooth flanks in the pairing between the gearwheel and rack and is dependent on the magnitude of said acceleration and on the mass of the vehicle seat with the person sitting on it. If this force exceeds a threshold value for the force-supporting capability of the pairing between the gearwheel and rack, said threshold value being predetermined by the shear strength of the material, then the material fails in the material-failure region and the vehicle seat can move relative to the vehicle structure. Kinetic energy here is converted into deformation (of the teeth) and is therefore dissipated; the vehicle seat therefore continues to move in braked fashion. This dissipates collision-induced acceleration peaks for the person sitting on the vehicle seat.
For this purpose, the teeth of the gearwheel are formed, for example, from harder material, with a greater level of shear strength, than the teeth of at least one region of the rack, and therefore, in the event of a vehicle collision, the teeth of the gearwheel shear off the teeth in said region of the rack and thus give rise to defined limitation of the collision force acting on the vehicle seat. The force-limitation action is triggered by the forces which act by way of the passenger, belt system and seat in the event of a collision. The vehicle seat console according to the invention provides for better passenger-protection levels in the event of a collision, in particular for passengers in lying positions, than a vehicle seat console without force-limitation action.
It is preferably the case that the respective rack is vehicle-mounted, and the associated gearwheel is mounted in a rotatable manner on the seat-mounted guide element or on the vehicle seat.
In an advantageous embodiment, the materials with different levels of shear strength have a metal, on the one hand, and a plastic material or a relatively soft metal, such as, for example, aluminum or copper, on the other hand.
It is preferably the case here that the gearwheel has metal teeth, and at least one region of the rack has teeth made of a plastic material or of a relatively soft metal, such as, for example, aluminum or copper, of which the level of shear strength is lower than that of the metal teeth of the gearwheel.
It is also advantageous if the toothing formation between the gearwheel and the rack is a double helical toothing formation.
The double helical toothing formation of the gearwheel here is preferably an open double helical toothing formation.
In one embodiment, which can be combined with other embodiments, the double helical toothing formation of the rack is a closed double helical toothing formation.
The invention also relates to a vehicle seat having a vehicle seat console according to the invention.
In addition, the invention is directed to a motor vehicle having at least one vehicle seat according to the invention.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.

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