The erbium-doped fiber amplifier comprises: a first erbium-doped optical fiber pumped by 0.98 .mu.m band light and amplifying the signal light; a first pump light source for producing the 0.98 .mu.m band light; a first optical coupler for coupling the 0.98 .mu.m band light with the signal light at an input portion of the first optical fiber; a second erbium-doped optical fiber pumped by 1.48 .mu.m band light and amplifying the signal light; a second pump light source for producing the 1.48 .mu.m band light; and a second optical coupler for coupling the 1.48 .mu.m band light with the signal light at an output portion of the second optical fiber; wherein a pump light isolator is installed between the first optical fiber and the second optical fiber for blocking the passing of the 1.48 .mu.m band light from the second optical fiber to the first optical fiber while allowing the passing of the signal light.

1. Field of the Invention
The present invention relates to an erbium-doped fiber amplifier pumped in the 0.98 .mu.m and 1.48 .mu.m bands and an optical fiber communication system having the same.
2. Description of the Related Art
Having many advantages over an electrical communication system, an optical fiber communication system has been actively studied and developed or already put into practical use in various fields. In such an optical fiber communication system, the propagation loss can be easily compensated by using erbium-doped fiber amplifiers which can directly amplify a light signal without converting it to an electrical signal.
Since the fiber amplifiers have a high saturated output, it is possible to increase the number of distribution ends in the entire optical system. Especially, when the fiber amplifiers are used for an optical subscriber system where information with a large capacity such as images is transmitted from a base station to home terminals or for a system called "Fiber To The Home", multi-channeling and multi-distribution can be more easily achieved. This contributes to facilitating the propagation of the system in the aspects of both the software and the cost. In the "Fiber To The Home" system, a multi-channel image signal transmission service called an optical CATV where the existing electrical CATV system has been developed to utilize optical transmission is predicted to be first put into practical use. Analog signal transmission is more advantageous for the above system than digital signal transmission because the former is compatible with the existing image information recording mode and is less expensive than the latter. Accordingly, the system adopting the analog mode is now being studied. The amplitude modulation or the frequency modulation is generally used for the analog signal transmission. In either case, the performance of the system depends on the carrier-to-noise ratio (CNR) and the distortion property. The CNR property is especially important for an AM-FDM (frequency division multiplexer) optical distribution system.
The fiber amplifier is essentially a low noise amplifier. Especially, it is known that, at 0.98 .mu.m band pumping, the noise figure (NF) degrades to the quantum limit of 3 dB because the maximum population inversion is realized at this wavelength. This noise property of the fiber amplifier when pumped in the 0.98 .mu.m band is reported, for example, in IEEE Photonics Technology Letters, vol. 2, No. 6, 1990, pp. 418-421.
It is also known that, at 1.48 .mu.m band pumping, the conversion efficiency is high because the pump wavelength and the signal light wavelength are close to each other. As a result, high output can be easily obtained. Power requirements for erbium-doped fiber amplifiers pumped at various wavelengths are reported, for example, in IEEE Photonics Technology Letters, vol. 4, No. 1, 1992, pp. 46-49.
It is considered, therefore, that a hybrid pumped fiber amplifier pumped at both 0.98 .mu.m and 1.48 .mu.m may provide low noise and high output power properties simultaneously. A study on a hybrid pumped preamplifier is reported in Electronics Letters, vol. 28, No. 17, 1992, pp. 1642-1643. A study on a hybrid erbium-doped fiber in-line amplifier is reported in ECOC'91, paper WeC9-2, 1991, pp. 585-587. The latter includes an optical isolator inserted in the middle portion of an erbium-doped optical fiber for suppressing a feedback effect. As for a hybrid erbium-doped fiber post amplifier, it is reported that the NF property degrades when 1.48 .mu.m pump light increases in The Institute of Electronics, Information and Communication Engineers, 1993 spring convention paper, No. 4, C-297. This paper proposes inserting an optical isolator in the middle portion of an erbium-doped optical fiber to prevent the lowering of the population inversion.
With the insertion of an optical isolator in the middle portion of an erbium-doped optical fiber, the output power and NF properties are improved for a fiber amplifier of a bidirectional pumping mode. This is because amplified spontaneous emission (ASE) propagating opposite to the direction of signal light is eliminated by the optical isolator. This is reported in The Institute of Electronics, Information and Communication Engineers, Optical Communication System Society, OCS92-27, 1992, pp. 9-16. However, since the ASE is suppressed under the high-input and high-output conditions required for a post amplifier, the effect of improving the properties by eliminating the ASE will be small for the post amplifier application.
An optical filter may be inserted in an end portion of a fiber amplifier pumped at 1.48 .mu.m or 0.98 .mu.m where a light signal has been amplified through an erbium-doped optical fiber for the purpose of eliminating beat noise generated by spontaneous emission. Such a fiber amplifier is reported in IEEE Photonics Technology Letters, vol. 2, No. 3, 1990, pp. 205-207.
It is obvious from the above description that a practical high-performance fiber amplifier can be obtained by utilizing the respective advantages of 0.98 .mu.m and 1.48 .mu.m pump wavelengths, thus increasing the output power and decreasing the NF of the amplifier.
The 0.98 .mu.m/1.48 .mu.m hybrid pumped fiber amplifier is theoretically considered to be effective for increasing the output power and decreasing the NF. In practice, however, when 1.48 .mu.m pump light is increased to obtain a high output power, the NF property degrades. On the contrary, when an optical isolator is inserted in the middle portion of an erbium-doped optical fiber in order to decrease the NF, the output power decreases. Thus, it is difficult to obtain a hybrid pumped post amplifier with high output power and low NF properties.
One object of the present invention is to provide a 0.98 .mu.m/1.48 .mu.m hybrid pumped fiber amplifier with high output power and low NF properties by isolating pump light using an optical component with low insertion loss such as an optical filter, by using an erbium-doped optical fiber having a small emission cross section in the 1.48 .mu.m band, or by pumping at a wavelength of the 1.48 .mu.m band capable of providing a smaller emission cross section.
Another object of the present invention is to provide a light signal transmission system with enhanced capabilities of long-distance transmission and multi-distribution.

Erbium-doped fiber amplifier and an optical fiber communication system

Matsushita Electric Industrial Co., Ltd.


An image decoloring apparatus includes a reader configured to read an image on a sheet to acquire image data, a storage section configured to store the image data acquired by the reader, and a first heater configured to heat the sheet. The apparatus further includes a difference extractor configured to extract difference image data based on first image data read from the sheet before it is heated by the first heater and second image data read from the sheet after it is heated by the first heater. The apparatus additionally includes a setting section configured to set a password required to access the difference image data.

An image decoloring apparatus having an image reading function and an image decoloring function is known.
Before a decoloring process, the image decoloring apparatus reads a sheet on which characters and figures (hereinafter, referred to as a handwritten image) written with decolorable ink decolored when heated and an image formed with color material decolored at a temperature different from that of the decolorable ink are printed. Thereafter, the image on the sheet is decolored, and the sheet after the image decoloring is read again. As a result, the image decoloring apparatus acquires image data before and after the image decoloring process. The image decoloring apparatus separates image data corresponding to the handwritten image and image data corresponding to an image other than the handwritten image based on the image data acquired before and after the image decoloring process.

Image decoloring apparatus and method setting password to access difference of image data read before and after heating


An article capable of repeatedly releasing ice from its surface is provided. Also provided is a composition capable of providing such release. The article and composition employ a polysiloxane having terminal ethylenic unsaturation, a polyhydrosiloxane, a platinum- or other metal-containing hydrosilation catalyst, and optionally, a non-functional polysiloxane free from ethylenic unsaturation. When applied to a surface and crosslinked, the article has a coating having a coating weight of at least 3 g/m.sup.2.

Ice build-up on the surfaces of such things as sign faces, signal transmission lines (e.g., telephone and electrical cables), automobiles, railroad cars, aircraft, heat exchange equipment, ice manufacturing facilities, buildings, transportation signs, roofing, snow removal equipment and the like presents a long recognized problem. While it is highly preferred to prevent ice build-up on such surfaces, no truly effective method of doing so has yet been found. Consequently, most techniques for resolving this problem involve techniques for the removal of an accumulation of ice from surfaces.
Thermal removal has been suggested. However, this technique requires a significant expenditure of energy and is generally ineffective where the ambient temperature is low.
Another technique involves the application of a silicon-containing coating to surfaces. However, this technique is not entirely satisfactory. U.S. Pat. No. 2,567,804 describes the use of a multilayer coating in which an organosilicon halide is first applied to the surface and then a prepolymerized silicone is applied thereover. The prepolymerized silicone has a viscous oily or greasy consistency. This approach suffers from the disadvantage of requiring the application of two separate layers of material. Additionally, the greasy top layer is aesthetically unpleasing and unsuitable for applications where repeated hand contact is to be made.
U.S. Pat. No. 3,522,202 describes the use of a composition consisting of (a) a dimethylpolysiloxane-containing terminal silicon bonded hydroxyl groups, (b) a methyl hydrogen polysiloxane, and (c) a methylphenylpolysiloxane containing terminal hydroxyl groups. This composition is applied from an organic solvent. As such, it not only presents potential pollution problems, it also necessitates the use of expensive solvent recovery systems. The use of solvent also adds a potential safety hazard.
U.S. Pat. No. 3,579,540 describes the use of a composition comprising a mineral acid, a solvent and an alkylpolysiloxane to render a nonporous surface water repellent. This composition also presents pollution and safety problems in its application. Additionally, however, the use of mineral acids presents problems of corrosion and also depolymerization of the polysiloxanes employed.
U.S. Pat. No. 4,271,215 discloses the application of a coating composition comprising a carboxy-functional siloxane fluid, an organic titanate, and a volatile diluent to a water-impermeable surface to give it ice release properties. This composition also presents pollution and safety problems in its application.
U.S. Pat. No. 4,301,208 discloses the application of a coating comprising a block copolymer of polycarbonate and dimethylpolysiloxane containing a silicone oil to render a surface capable of releasing ice. This composition is applied from solvent and accordingly presents the above-identified pollution and safety problems. Furthermore, it is a thermoplastic composition and the literature indicates that it has poor adhesion to some substrates. Still further, the resulting material is only physically crosslinked. This type of crosslinking is reversible unlike that of the compositions employed in the present invention.
U.S. Pat. No. 4,636,324 discloses the use of a composition comprising 40 to 99.6 weight % of an organopolysiloxane, 0.2 to 30 weight % of an alkali metal salt, and 0.2 to 30 weight % of a liquid and/or a solid paraffin. U.S. Pat. No. 4,448,919 discloses the use of a composition comprising from 70 to 99.8 weight percent of an organopolysiloxane and 0.2 to 30 weight percent of an alkali metal salt. The alkali metal salts employed in the '324 and '919 compositions can be leached out of the compositions, decreasing their ice-releasing capabilities and causing corrosion problems.
German Offenlegungsschrift DE 3451100 A1 describes the use of a composition containing .varies.- and .omega.-dihydroxypropyl(dioganosiloxanes), alkyl-triacetoxysilanes, fillers, pigments, solvents, and optionally .varies.,.omega.-bis(trimethylsiloxy)poly(dimethylsiloxane). This composition employs a silanol functional polysiloxane. In addition, it is applied at a thickness of 1.5 mm. This corresponds to a coating weight of approximately 1500 g/m.sup.2 and is significantly heavier than is employed in the present invention.
Yet another approach that has been tried is the use of polytetrafluoroethylene to reduce the adhesion of ice on surfaces. Again, however, this approach has not proven to be entirely satisfactory. This technique requires the application of a coating or layer of a fairly expensive polymer and provides a surface which, at best, provides only marginal ice release capabilities.
U.S. Pat. Nos. 4,504,645 and 4,533,575 disclose the use of latently curable organosilicone release coating compositions which are applied as a thin layer (e.g. 1 g/m.sup.2) to provide release from an adjacent adhesive layer. Thin coatings of this type do not provide suitable ice release capability.
International Application No. PCT/GB 88/00285 discloses a system for releasing ice from a surface which employs a two component polymeric coating on a surface. The first component is not removable from the surface by solvents. The second component is dissolved or dispersed homogeneously in the first component but is not bonded to the first. The first component is physically or chemically grafted to the surface and more preferably contains a reactive end or side group. The second component preferably has an oily, waxy or greasy consistency. Mineral oils, organic polysiloxanes, fluorinated polymers, ethylene/propylene copolymers and polyurethanes are said to be useful as the first and second components.
U.S. Pat. No. 2,494,920 describes the application of a coating containing an organopolysiloxane, a heat resistant inorganic filler, and a peroxide (such as a diacyl peroxide). The composition is applied to a substrate and then baked until it has reached a temperature of 180.degree. C. for two minutes. This composition is said to render surfaces water repellent. However, the use of fillers tends to render the composition opaque and hence unsuitable for many applications. Moreover, the use of high temperatures to polymerize the coating is undesirable.

Ice release composition, article and method

Minnesota Mining and Manufacturing Company


A color electrophotographic apparatus with a developing unit for one color larger than the developing units for the other colors, comprising a first optical path where the laser signals irradiated from a laser exposure device reach a mirror at the central portion of a columnar assembly of image forming units and a second optical path where the laser signals reflected by the mirror reach and expose the photoconductor of the image forming unit at the image forming position formed between two adjacent developing units is provided.

The present invention relates to a color electrophotographic apparatus applicable to color printers, color copying machines, and color facsimiles.
In a color electrophotographic apparatus, a full color image is formed on an acceptor sheet such as a paper sheet by superimposing images of black, yellow, magenta and cyan toners. The color electrophotographic apparatus includes a continuous transfer type using a transfer belt in an image superimposing member for forming a full color image, and a transfer drum type using a transfer drum in the image superimposing member.
A conventional color electrophotographic apparatus disclosed in the Japanese Patent Application Laid Open Hei No. 7-36246 will be explained with reference to FIG. 25.
FIG. 25 is a side cross-sectional schematic view showing an entire configuration of a conventional color electrophotographic apparatus. The conventional color electrophotographic apparatus shown in FIG. 25 is the continuous transfer type using an intermediate transfer belt in the image superimposing member, a sheet up to an A-4 paper size (210.times.297 mm) can be printed. In the below-mentioned explanation, the same numeral will be applied to portions having the same function, and in the case that the toner color needs to be differentiated, letters designating the colors such as Y for yellow, M for magenta, C for cyan, and BK for black are added to the numerals.
In FIG. 25, an intermediate transfer belt unit 101 comprises an intermediate transfer belt 102, a first transfer roller 103, a second transfer roller 104, a cleaner 105, and a waste toner box 106. In the configuration, the full color image is formed by superimposing toner images of the four colors on the intermediate transfer belt 102.
As shown in FIG. 25, the conventional color electrophotographic apparatus comprises four sets of image forming units 107BK, 107C, 107M, 107Y of the same shape for black, cyan, magenta and yellow toners. The image forming units 107BK, 107C, 107M, 107Y are arranged in a substantially ring shape to form a substantially columnar assembly of image forming units 108. Each of the image forming units 107BK, 107C, 107M, 107Y is mounted in a predetermined position in the color electrophotographic apparatus. Thereby, the image forming units 107BK, 107C, 107M, 107Y are coupled to a driving system and an electric system of the conventional color electrophotographic apparatus by a coupling member (not shown), so that the image forming units 107BK, 107C, 107M, 107Y are integrated mechanically and electrically.
In the assembly of the image forming units 108, each of the image forming units 107BK, 107C, 107M, 107Y is supported by a supporting member (not shown) to be arranged in a ring-like shape. The assembly of the image forming units 108 is driven by a driving motor (not shown), so that the assembly of the image forming units 108 is rotated around a cylindrical shaft 109 arranged at the center of the assembly of the image forming units 108. The cylindrical shaft 109 is unrotatably fixed to an outer case of the conventional color electrophotographic apparatus.
When each of the toner images is formed, the image forming units 107BK, 107C, 107M, 107Y are rotated so that the respective photoconductors 118 are located at a image forming position 110 facing to the first transfer roller 103 for supporting the intermediate transfer belt 102. The image forming position 110 is an exposed position where laser signals 111 from a laser exposure device 112 expose the photoconductors 118.
As shown in FIG. 25, the laser exposure device 112 is arranged at a lower side of the conventional color electrophotographic apparatus. As shown by a dashed line in FIG. 25, the laser signals 111 irradiated from the laser exposure device 112 reach an opening formed on the shaft 109 through an entrance 113 of an optical path between the image forming unit 107M for magenta and the image forming unit 107C for cyan. The laser signals 111 are reflected by a mirror 114 fixed in the shaft 109. The laser signals 111 reflected by the mirror 114 enter the image forming unit 107BK located at the image forming position 110 through an exposure entrance 115 of the image forming unit 107BK.
The laser signals 111 having entered the image forming unit 107BK irradiate a side portion to be exposed of the photoconductor 118 through an optical path between a developing unit 116 and a cleaner portion 117. The laser signals 111 irradiating the photoconductor 118 are scanned in a direction of a generating line on the photoconductor 118, so that the photoconductor 118 is exposed and a black toner image is formed thereon.
The black toner image formed on the photoconductor 118 is transferred to the intermediate transfer belt 102 by the contact with the intermediate transfer belt 102.
Subsequently, the assembly of the image forming units 108 is rotated in the clockwise direction (shown by an arrow "Y") by 90 degrees, so that the image forming unit 107Y for yellow is arranged at the image forming position 110. Operations similar to that of the above-mentioned forming process for the black toner image are conducted, and thereby, a yellow toner image is superimposed on the black toner image transferred on the intermediate transfer belt 102.
Operations similar to that of the above-mentioned forming process for the black toner image or the yellow toner image are conducted in the image forming units 107M and 107C for magenta and cyan. Thereby, the full color image is formed on the intermediate transfer belt 102.
The full color image on the intermediate transfer belt 102 is transferred on a paper sheet supplied to the conventional color electrophotographic apparatus by a third transfer roller 119, and further the full color image transferred on the paper sheet is fixed by a fuser 120.
In the conventional color electrophotographic apparatus, four developing units 116 for each color are formed by the same size based on the premise that the black, cyan, magenta and yellow toners are consumed at the same rate.
However, in the inventor's experimental investigation, it is found that each color has a different consumption amount, and in particular, a black toner is consumed in a greater amount compared with the other colors. Therefore, in the conventional color electrophotographic apparatus, there occurs problems in that the black toner needs to be supplied more frequently than the other colors, requiring labor in the maintenance.
Furthermore, in the conventional continuous transfer type color electrophotographic apparatus, each of the four photoconductors 118 comes in contact with the intermediate transfer belt 102 and comes apart from the intermediate transfer belt 102 repeatedly. Therefore, there is a problem in that the intermediate transfer belt 102 stretched with a high tension is liable to generate vibration, resulting in disturbing the image. In particular, in the apparatus having a long distance between the roller shafts for stretching the intermediate transfer belt 102, an amplitude of the vibration becomes larger.

Color electrophotographic apparatus having a split toner reservoir


Provided are a composite powder comprising a core particle which is spherical and has a refractive index of from 1.40 to 1.60, and a coating component which is coated on the surface of the core particle in film form and has a refractive index of from 2.00 to 2.90, and a coloring composition containing the composite powder. The composite powder or coloring composition is coated on a coating surface to form a composite powder layer. The composite powder layer causes light interference to exhibit a color on the surface. The composite powder and coloring composition are used in various fields.

1. Field of the Invention
The present invention relates to a composite powder and a composition containing this composite powder. More specifically, the present invention relates to a composite powder which can give a desired color by light interference and a coloring composition comprising the same.
2. Description of Related Art
A color is a quite important element which can give us a physiological influence or a psychological influence. Actually, a color conditioning technology which creates a safe efficient working environment or a healthy comfortable living environment using a physiological or psychological effect that a color can give us has been used in various fields.
Usually, when a product is colored, various color pigments are employed. The color pigments are those for applying a fixed color to a product utilizing a phenomenon of light absorption or scattering.
However, it is difficult to meet various requirements for colors these days with only the color pigments.
Accordingly, a pearlescent pigment such as titanium dioxide-coated mica or the like, which is a pigment with the use of a phenomenon of light interference, is provided in addition to the above-mentioned color pigments. The great characteristic feature of the pearlescent pigment is that a "flip-flop effect" by which a color is delicately changed according to an angle can be imparted to a product obtained by using the same.
This pearlescent pigment has currently been used in various fields such as cosmetics and the like.
However, pearlescent pigments which are currently used are not necessarily free from defects.
For example, with respect to an ordinary pearlescent pigment which is used as a pigment of an external composition such as cosmetics or the like, various approaches have been attempted on the color. However, particles thereof are laminar or flaky, and cosmetics containing the same lack smoothness. Thus, the pearlescent pigment is problematic in the use. Further, since a gloss of the ordinary pearlescent pigment is generally quite strong, it is unavoidable that the amount thereof in cosmetics tends to be limited.
In one aspect, the problems attendant on the use and the excessive gloss can be solved by making the particles of the pearlescent pigment spherical. However, since the spherical particles have a great light scattering property, it is quite difficult to create a color by interference.
The problem to be solved by the present invention is to provide a novel composite powder which does not have the defects of such a conventional pearlescent pigment and by which a color can be created by interference, and to provide means for using the powder in various fields.

Composite powder and coloring containing the same


A recording and reproducing apparatus is capable of editing video signals and audio signals recording additional information data for controlling the reproduction output level. The recording side includes an additional information data generating circuit, a time division multiplexing circuit for time-division multiplexing a video signal data and audio signal data and the additional information data, and a recording head. In independent areas on a recording medium, the video signal data, audio signal data and additional information data are individually recorded. The reproduction side includes a reproduction head, a data separation circuit for separating the video, audio and additional information, an additional information data detecting circuit for producing output level data, and a circuit for controlling the levels of the reproduced video and audio signals depending on the output level data.

1. Field of the invention
The present invention relates to a video signal recording and reproducing apparatus for recording and reproducing video and audio signal, and more particularly to a video signal recording and reproducing apparatus suited for editing the video signal or audio signal or both.
2. Description of the Prior Art The video tape recorder (VTR, hereinafter) having an editing function accompanying operational processing of a recorded signal in desired such as, for example, fading-in and fading-out of the video signal or audio signal. To realize such an editing function, a method is known that reproduces a recorded signal, carries out specified signal processing of the reproduced signal, and records the processed signal in the area where the reproduced signal has been recorded on the recording medium. For example, in the recording and reproducing apparatus disclosed in Japanese Laid-Open Patent Application No. 60-223007 or No. 2-76102, in order to reproduce a track located a specific time in advance of the track traced by a recording head (prior reproduction), a prior reproduction head is disposed in addition to the recording head on a rotary cylinder.
In a conventional constitution, editing of a digitally recorded signal accompanying the operational processing, such as fade-in and fade-out, requires reproduction signal processing such as error detection and correction of the reproduced data prior to recording, the above-mentioned operational processing, and recording signal processing such as error correction code addition to the signal after the operational processing. Further, if the recorded signal is compression coded video signal or audio signal, decoding of the reproduction signal and compression coding of the signal after the operational processing are required.
These additional signal processings are complicated and increase the hardware scale. Further, the quantity of data to be reproduced by the prior reproduction must be increased with the increase of the time required for such signal processing. The greater the prior reproduction quantity, the larger becomes the difference between the mounting heights of the recording head and the prior reproduction head in the VTR having helical scan recording type with a rotary head cylinder. Considering the VTR for recording wide-band signals such as High Definition TV signals, having a large number of tracks per frame the difference in the mounting heights of the prior reproduction head and recording head is required to be about several millimeters, and each head must be mounted at a precision of several microns or less. If there is an error in head mounting, while the prior reproduction head is on the track to be reproduced, the recording head may be off the track to be recorded, and precise editing cannot be expected.
In a method disclosed in Japanese Laid-Open Patent Application No. 1-152877, the principal information composed of video signal or audio signal is recorded in a state without being faded, and a fade control signal is recorded as the duty of the rotary head phase control signal. In reproduction, the output level is controlled by using the fade control signal. In this method, fade-out and fade-in editing without prior reproduction is possible. However, in order to rewrite the fade control signal, the rotary head phase control signal also must be rewritten. If the timing of the control signal is deviated from its original timing, the tracking varies. Therefore, in order to obtain a stable reproduction image, a signal of the same timing as before rewriting must be recorded at an extremely high precision.


A system and process for sealing collections of rolls in a bundle. The rolls, which can be multiply packaged rolls or individually packaged or unpackaged rolls, are accumulated and conveyed until they are aligned and then collected in a group. Successive groups are then inserted in a tube of film which is severed and sealed about each group to complete a bundle. The sealing system includes at least two sealing axes, with each axis having at least one die set. The axes are synchronized and individually driven at variable velocities during their paths of travel.

This invention relates to packaging machinery, and in particular to a system for processing a group of items and sealing them in a plastic film as the items follow a path of travel.
The invention is directed to horizontal form, fill and seal machinery, and particularly that type of machinery in which items to be packaged are enveloped in a plastic film. Other applications of the invention are possible, however.
The heart of a form, fill and seal machine is the sealing apparatus. No matter how quickly items to be packaged might be collected and grouped, it is imperative that they be fully sealed in a package that will not inadvertently open, which is as tightly sealed as desired, and which has all graphics properly displayed and aligned in the packaging material.
The first horizontal form, fill and seal machine was developed by Sam Campbell of Hudson Sharp Company, Green Bay, Wis. in the late 1940's. This machine consisted of a product infeed conveyor, a horizontal forming shoulder for enveloping items within a packaging material, a rotary back seam sealing device which acted as the prime mover for the film, and horizontally rotating sealing bars which both sealed and crush cut the wrapping material. This machine was designed for high speed overwrapping of candy bars and the like, and became known in the industry as the "Campbell Wrapper".
When the Campbell Wrapper was developed, wrapping materials prevalent at the time were heat sealing cellophane and heat seal paper using nitrocellulose coatings as the heat seal medium. It was well known at the time, and is still well known, that in order to obtain a good heat seal, three fundamental criteria must be present--time, temperature and pressure. Without these three criteria in the right proportions, efficient heat sealing cannot be obtained. As early as the 1930's, the DuPont Company, the inventors of heat sealable and moisture proof cellophane, evolved a testing method utilizing time, temperature and pressure in order to provide a standard against which the integrity of heat seals is measured.
With the introduction of polyethylene and other plastic films, the same criteria remain true at the present time. However, because heated plastics lose their structural integrity, cooling must also be a factor in the formula.
One of the most important speed inhibiting factors of the Campbell Wrapper was the very short sealing or dwell time utilized for sealing of the wrapping material. The single rotating horizontal sealing heads of the Campbell Wrapper have their surfaces curved in order to maintain sealing contact. This requires that the time that the sealing heads are in contact with the wrapping material is very short. As a result, the short dwell time has been compensated for by relatively high unit pressure and high temperatures.
Longer dwell times with lower temperatures was a goal constantly sought. Several attempts were made to overcome the short dwell time problem of the Campbell Wrapper, and in the late 1950's or early 60's, a system was developed utilizing multiple heat sealing jaws located on top and bottom chains, the pitch of the sealing jaws being equal to the finished length of the package. This added substantial dwell time, and in fact produced an improved Campbell Wrapper having very high speed. However, due to the configuration of this improvement, in order to change a finished package length, the entire top and bottom sealing systems had to be replaced with a different set of sealing jaws on different chains with the appropriate pitch to coincide with the new package length. While machines of this type were made, the difficulties of changing from one size to another were a severely inhibiting factor.
Another attempt to increase dwell time was to include two horizontal sealing heads in a machine, the first sealing head imparting a "preheat" and the second sealing head adding additional heat and severing the material. Although this configuration did increase speed somewhat, the additional dwell time achieved was marginal.
A further attempt to increase dwell time was to have an individual sealing die close, move in the direction of the film for a short distance, open and then return to the ready position for the next seal. Yet another system developed had rotating dies operating in a "D" motion with the flat side of the D being the dwell. In all cases where dwell time was extended on a single die machine, the mechanics of the systems have been speed inhibiting, and at the most give a dwell time of 50% of an individual package making time, i.e. at 60 per minute the maximum dwell time would be 500 milliseconds.
The first multi-die machine, with the ability to maintain the flexibility of being able to change over easily from one package to another, was designed in the late 1950's by the Cloud Corporation, Chicago, Ill., and was patented. The Cloud patent was subsequently purchased by The Hayssen Manufacturing Company, the assignee of the present application. Hayssen still manufactures equipment covered by the Cloud patent. The Cloud device consists of a series of hinged sealing dies which are slidably mounted on a drum, each die having a mechanism for allowing it to either slide on the drum or grip and travel with the drum. In practice a series of the dies are backed up with the foremost die being stationary in the 12 o'clock position. A release mechanism, operated by a signal from either the product itself in the case of an unprinted film or by a registration mark on the film when proper orientation of graphics is necessary, releases a die which grips the drum and rotates with the drum. The hinged top die closes and is held under pressure while the sealing and cutting takes place. At a speed of 60 packages per minute and a package length of approximately 8 inches, up to 5 seconds of dwell time is achieved compared to something less than 250 milliseconds on a standard Campbell Wrapper machine.
Another phenomenon in horizontal form, fill and seal packaging machines must also be considered. This is the pitch length of the product in the unclosed tube of packaging material verses the finished package length. This is due to the fact that as the packaging material is collapsed between succeeding products or groups of products in the tube, the distance between the products must be reduced in order to obtain a seal, or else the packaging material is stretched and quite probably weakened or damaged. In order to obtain a very tight package, the distance between items in the tube being sealed is one product height plus the width of the sealing bar. Thus, as the product height increases, the differential between the length of pitch between items in the tube and the finished package length becomes greater and greater.
This phenomenon is not a problem in a Campbell Wrapper, which has only a single die, since only one seal and cut is made at a time. Therefore, a package being sealed and cut can change velocity without restraint during the sealing and cutting operation. However, whenever multiple dies are in contact with the film, and where these multiple dies are operated at a constant velocity in a single drive, this phenomenon is accommodated by having the collapsing sealing head pull excess film from downstream. This results in a jerking motion of the film, and is an undesirable characteristic, particularly where several products are simultaneously being packaged within the tube. The incoming film must therefore operate at a variable velocity.
Cassoli U.S. Pat. No. 4,679,379 is directed to a horizontal form, fill and seal machine for packaging of large bundles of toilet tissue and household towels. This machine has single dies with product being intermittently fed through the sealing and wrapping area and intermittently discharged. However, the apparatus has a single die and intermittent operation, therefore resulting in fairly slow operation. The maximum speed touted for a Cassoli-type system is 12 packages per minute, although slower speeds are normally attained.
The system of the present invention overcomes all problems of the prior art by having two or more independently driven die carrying systems (axes) with each axis having one or more die sets. This provides significant advantages:
1. Extremely long dwell times are permitted, allowing the appropriate heating and cooling required for high speeds. PA1 2. The incoming product and film are driven at a constant velocity, with the individual sealing dies slowing to the point of closure on the film in order to accommodate the change in pitch between the products being sealed. All dies downstream of the closing die follow the speed of the closing die. Thus, there is constant velocity of the film and product to the first sealing die, and then variable velocity from then on during the sealing process. The upstream film is not stretched or jerked by such a process. PA1 3. Speeds of 45 packages per minute are attainable in a system according to the invention having three die sets in contact with the film at any one time, while providing 4 seconds of sealing and cooling time, more than adequate to obtain a seal of proper strength and integrity.
Because the dies of the invention have a variable velocity which can be programmed, the multi-axis, multi-die design of the present application is not confined to traditional horizontal form, fill and seal machines. For example, the concepts of the present application can be employed in sealing machines using two rolls of film, one roll above and one roll below a conveying plane, where heat sealing jaws seal the films together to form a curtain of film. In such apparatus, the product or products to be packaged are pushed through the curtain of film and the sealing dies come together to seal and cut, forming another curtain and also completing the package at the same time. Very often such packages are wrapped in a shrink film and then sent through a shrink tunnel. The concepts of the present application can be employed to increase considerably the speed of this type of machine.

Sealing system and process for packaging machine


A process for the fabrication of an MOS transistor.. The process comprises the steps of forming a gate oxide film on a substrate, forming a p.sup.+ polysilicon film doped with p type impurity ions over said gate oxide film, coating an insulating film and a photoresist film over said p.sup.+ polysilicon film, in sequence, subjecting the resultant structure to a patterning to expose a portion of said insulating film, applying an etching method to said exposed insulating film with said photoresist film used as a mask, implanting fluorine ions in said p.sup.+ polysilicon film with resultant insulating film used as a mask, removing the remaining photoresist film, carrying out an annealing method to form a low density p.sup.- source/drain regions, applying an etching method to said p.sup.+ polysilicon film to form a gate with said resultant insulating film used as a mask, removing said resultant insulating film, depositing an oxide film entirely over the resultant structure, applying an anisotropic etching to said oxide film to form spacers at side walls of said gate, implanting p type impurity ions in said substrate at a high density to form high density p.sup.+ source/drain regions neighboring said low density p.sup.- source/drain regions, thereby the device having a storage capacity of not less than 256M can be fabricated more reliably and more advantageously.

1. Field of the Invention
The present invention relates in general to a process for fabricating an MOS transistor, and more particularly to improvement in a short channel effect and a hot carrier effect and a threshold voltage in the MOS transistor.
2. Description of the Prior Art
In a conventional p type MOS transistor, at edge portions of a gate electrode occurs a high electric field, which forces hot carriers to be generated. The generated hot carriers are often trapped in a gate insulating film in the transistor, causing a charge trap or interface state to occur in the insulating gate. These hot carriers serve to degrade an operation characteristic of a p type MOS transistor fabricated and reduce the use life expectancy thereof.
In an effort to curtail the hot carrier effect, a p type MOS transistor having a lightly doped drain (hereinafter "LDD") structure has been proposed. This p type MOS transistor of LDD structure will be explained by referring to FIG. 1 for better understanding of the background of the invention. There is shown a step diagram for the conventional process flow of the p type MOS transistor of LDD structure.
As shown in FIG. 1, in step A, a gate oxide film 13 is formed over an n type semiconductor substrate 11. A p.sup.+ type polycrystalline silicon (polysilicon) film doped with p type impurity ions is entirely formed on the gate oxide film 13 and is then subjected to a patterning so as to form a gate 15. Using the gate 15 as a mask, p type impurity ions such as B ions and BF.sub.2 ions are implanted at such a low density as to form source/drain regions having a low p.sup.- density.
Subsequently, in step B, the fabrication of the p type MOS transistor of LDD structure is finished. For this, firstly, an oxide film is deposited entirely on the substrate and is then subjected to the treatment of anisotropic etching so as to form spacers 19 at side sites of the gate 15, leaving them shaped into side walls, respectively, as shown in the figure. Next, using the spacers 19 and the gate 15 as a mask, p type impurity ions such as B ions or BF.sub.2 ions are implanted in the substrate 11 at such a high density as to form source/drain regions 21 having a high p.sup.+ density.
In the above MOS transistor of LDD structure, the drain region 17 having a low p.sup.- density allows the high electric field applied to the drain region to become lowered, so that the degradation of operation characteristics in the device caused by the hot carriers can be prevented, thereby improving the reliability of the device.
In case of fabricating a very small LDD MOS transistor for a device having a storage capacity of 256M or more, the p.sup.- source/drain regions which have a function of eliminating the hot carrier effect must have a shallow junction depth, for example, several hundreds .ANG. such that a short channel effect is not affected.
However, the conventional process utilizing ion implantation method finds difficulty in producing an LDD MOS transistor having a storage capacity of 256M or more. Hereinafter, this problem will be briefly discussed for better understanding. As mentioned above, as a p type impurity used for forming p type source/drain regions, B or BF.sub.2 is employed. Since boron (B) ions have so great diffusivity, the low density p.sup.- source/drain regions having a shallow junction are hard to form by the application of ion implantation process. Accordingly, the short channel effect of the device is reversely affected.


First two dimensional plane is defined by phase of modulated signal and first vector corresponding to first signal point to be decided is defined. Then, first inner product by the first vector and second vector corresponding to last decided signal point is made and the second vector is transformed into third vector which is ninety degrees advanced. Next, second inner product of the first vector and third vector is made and the region of the first signal is decided in the two dimensional plane in accordance with the first and second inner product.

1. Field of the Invention
The present invention relates to a method for deciding region of .pi./4 shift quadriphase shift keying (QPSK) modulated signals used for demodulation of a signal which modulated by .pi./4 shift QPSK modulating method.
2. Prior Art
FIG. 6 shows a block diagram of the structure of a usual decision apparatus of prior art for .pi./4 shift QPSK modulated signals. According to this FIG. 6, an input signal is provided by input terminal 1, an A/D converter 2 coverts the input signal to a digital signal S, a signal cos(.omega.ct) is produced by a generator 3, a .pi./2 phase shifter 4 generates a signal sin(.omega.ct) by shifting the phase of the signal cos(.omega.ct) by .pi./2.
A mixer 5 multiplies the signal S and the signal cos(.omega.ct), a mixer 6 multiplies the signal S and the signal sin(.omega.ct), low pass filters (LPF) 7 and 8 respectively limit the bandwidth of the output signals of the mixers 5 and 6, a decision circuit 9 decides on the basis of the output signals from the LPF 7 and 8 to which of the 8 parts of the phase space, indicated in FIG. 7, the input signal belongs to, the decision result coming from the decision circuit 9 is put out to a output terminal 10.
Furthermore, the decision of the decision circuit 9 is carried out as shown below. In FIG. 8, four waveforms are shown, they correspond to the four equations listed below. In FIG. 8, a curved line a corresponds to wavefunction (1), a curved line b corresponds to wavefunction (2), a curved line c corresponds to wavefunction (3) and a curved line d corresponds to wavefunction (4). EQU f.sub.1 =cos(.omega.) (1) EQU f.sub.2 =sin(.omega.) (2) EQU f.sub.3 =f.sub.1 +f.sub.2 =cos(.omega.)+sin(.omega.) (3) EQU f.sub.4 =f.sub.1 -f.sub.2 =cos(.omega.)-sin(.omega.) (4)
In FIG. 9, the signs of sign(f.sub.1), sign(f.sub.2), sign(f.sub.1 +f.sub.2), sign(f.sub.1 -f.sub.2) which correspond to functions (1) to (4) are listed while the phase angle varies from 0 to 2.times..pi..
Consequently, when the output signals from the LPF 7 and 8 as well as their computed sign combinations coincide with one of the combinations shown in FIG. 9, the decision circuit 9 decides to which of the eight areas 1 to 8 of FIG. 7 the input signal belongs to.
With the decision apparatus as described above, an explanation about the way of operation of the decision of the decision circuit 9 on the input signal is described with reference to a flow chart shown FIG. 10. First, the input signal inputted from the input terminal 1 is converted to the digital signal S in the A/D converter 2. Next, the digital signal S is multiplied by the signal cos(.omega.ct) in the mixer 5 and the multiple result outputs as a signal S.times.cos(.omega.ct) from the mixer 5. Concurrently, the digital signal S is multiplied by the signal sin(.omega.ct) in the mixer 6 and the multiple result outputs as a signal S.times.sin(.omega.ct) from the mixer 6. Then the decision circuit 9 proceeds with step SA1 (see FIG. 10) and substitutes the signal S.times.cos(.omega.ct) for a variable x and proceeds with step SA2.
In step SA2, the signal S.times.sin(.omega.ct) is substituted for the variable y and step SA3 follows next.
In step SA3, it is decided whether the variable x is not negative. If the result of this decision is "Yes", step SA4 follows next.
In step SA4, it is decided whether the variable y is not negative. If the result of this decision is "Yes", step SA5 follows next.
In step SA5, it is decided whether a difference (x-y) of the two variables x and y is not negative. If the result of this decision is "Yes", step SA6 follows next.
In step SA6, it is decided that, according to FIG. 9, the input signal falls into area 1 of FIG. 7, then an assigning phase P.sub.n =0 degree and step SA7 follows next.
In step SA7, a phase difference (.DELTA.=P.sub.n -P.sub.n-1), where P.sub.n is the phase of the existing input signal and P.sub.n-1 is the phase of the previous input signal, is obtained and is outputted from the output terminal 10 of FIG. 6 as the result of the decision, then this a whole operating cycle is finished.
If on the other hand the result of the decision of step SA5 is "No", that is, the difference of the variable x and the variable y, the difference (x-y) is less than 0 step SA8 follows next.
In step SA8, it is decided that, according to FIG. 9, the input signal falls into area 2 of FIG. 7, then the assigning phase P.sub.n =45 degrees and step SA7 follows next.
If on the other hand the result of the decision of step SA4 is "NO", that is, the variable y is less than 0, step SA9 follows next.
In step SA9, it is decided whether a sum (x+y) of the two variables x and y is not negative. If the result of this decision is "Yes", step SA10 follows next.
In step SA10, it is decided that, according to FIG. 9, the input signal falls into area 8 of FIG. 7, then the assigning phase P.sub.n =315 degrees and step SA7 follows next.
If on the other hand the result of the decision of step SA9 is "No", that is, the sum of the variables x and y, the sum (x+y) is less than 0, step SA11 follows next.
In step SA11, it is decided that, according to FIG. 9, the input signal falls into area 7 of FIG. 7, then the assigning phase P.sub.n =270 degrees and step SA7 follows next.
If on the other hand the result of the decision of step SA3 is "No", that is, the variable x is less than 0, step SA12 follows next.
In step SA12, it is decided whether the variable y is not negative. If the result of this decision is "Yes", step SA13 follows next.
In step SA13, it is decided whether the sum (x+y) of the two variables x and y is not negative. If the result of this decision is "Yes", step SA14 follows next.
In step SA14, it is decided that, according to FIG. 9, the input signal falls into area 3 of FIG. 7, then the assigning phase P.sub.n =90 degrees, step SA7 follows next.
If on the other hand the result of the decision of step SA13 is "No", that is, the sum of the variable x and variable y, the sum (x+y) is less than 0, step SA15 follows next.
In step SA15, it is decided that, according to FIG. 9, the input signal falls into area 4 of FIG. 7, then the assigning phase P.sub.n =135 degrees and step SA7 follows next.
If on the other hand the result of the decision of step SA12 is "No", that is, the variable y is less than 0, step SA16 follows next.
In step SA16, it is decided whether the difference (x-y) of the two variables x and y is not negative. If the result of this decision is "Yes", step SA17 follows next.
In step SA17, it is decided that, according to FIG. 9, the input signal falls into area 6 of FIG. 7, then the assigning phase P.sub.n =225 degrees and step SA7 follows next.
If on the other hand the result of the decision of step SA16 is "No", that is, the difference of the variable x and variable y, the difference (x-y) is less than 0, step SA18 follows next.
In step SA18, it is decided that, according to FIG. 9, the input signal falls into area 5 of FIG. 7, then the assigning phase P.sub.n =180 degrees and step SA7 follows next.
By the way, the above mentioned prior art about a decision apparatus for .pi./4 shift QPSK modulated signals had the weak point of involving a mere 45 degrees phase margin in it's decision.
Moreover, if the decision circuit 9 uses a Digital Signal Processor (DSP) and processes the above mentioned operation by software, the problem was that the DSP processing software is complicated.

Method for deciding region of PI/4 shift quadriphase shift keying modulated signals


A laser beam recording apparatus having a parallel-plane plate, such as a dust proof glass plate or a light controlling filter, which is disposed across the optical path of the laser beam. The beam transmitting surfaces of the parallel-plane plate are so inclined that the angle of incidence of the laser beam thereon is not zero throughout the scanning movement of the laser beam.

The present invention relates to a laser beam recording apparatus, such as a laser beam printer, wherein a photosensitive member is scanned with a laser beam which is modulated in accordance with an image information to be recorded.
Conventional laser beam printer will first be described in conjunction with the accompanying drawing, FIG. 1.
The laser beam printer includes a photosensitive member 1, which is in the form of a drum, rotatable in the direction shown by the arrow. Around the photosensitive drum 1, there are provided a charger 2 for uniformly charging the surface of the photosensitive drum 1 and developing means 3 for developing an image on the photosensitive drum 1. The printer further includes a paper feed cassette 4, registration roller 6, an image transfer charger 7, image fixing means 8 and a cleaner 9.
The laser beam printer is provided with a housing 10 for accommodating an optical system for the laser beam L. The housing 10 contains a laser beam oscillator 11 which generates a laser beam L modulated in accordance with external image signals, a polygonal mirror 12 for deflecting the modulated laser beam L to scan therewith the photosensitive drum 1 in the direction of the rotational axis, a driving motor 13 for rotating the polygonal mirror at a constant rotational speed, an f.multidot..theta. lens 14 for imaging the deflected laser beam L on the surface of the photosensitive drum 1, and a reflection mirror 17 for deflecting the optical path.
The housing 10 is provided, partly opposed to the photosensitive drum 1, with an opening for allowing the laser beam L to emerge. The opening is sealed by a transparent parallel-plane plate, such as a glass plate, which functions as a dust proof plate for protecting the laser beam optical system within the housing 10 from the dust.
Further, a filter 16 may be disposed across the optical path of the laser beam L, when, for example, the amount of light is to be controlled.
In operation, the laser beam L modulated in accordance with the external image information signals, scans the photosensitive member, i.e., drum 1 at its surface which has been uniformly charged by the charger 2. By this scan, an electrostatic pattern is formed on the photosensitive drum 1 in accordance with the image signal. The electrostatic pattern is then visualized by the developing means 3. The visualized image is then transferred by the transfer charger 7 onto a transfer material fed from the feed cassette 4. The transfer material bearing a visualized image thereon is conveyed to the fixing means 8, whereat the image is fixed thereon. The transfer material is then discharged out. On the other hand, the residual developer remained on the photosensitive drum 1 is removed therefrom by cleaning means 9 to make it ready for the next image formation.
It has been found that the resultant images produced by the above-described apparatus sometimes have unintentional stripe patterns.
The inventor has been making detailed investigation on this problem, and finally found that the cause of this is the interference of the laser beam, which takes place in the parallel-plane plate of uniform thickness, such as the glass plate 15 and the filter 16, disposed across the optical path.
The cause which was found as a result of the investigation will be explained in detail in conjunction with FIG. 2, wherein the parallel-plane plate 15 (or 16) which is transparent for the laser beam L is shown as viewed in the direction of A for the dust proof glass plate 15 (or B for the filter 16). The laser beam L, which has been deflected by the polygonal mirror 12 (not shown in this Figure), is transmitted through the parallel-plane plate 15 (or 16) to the photosensitive drum 1. The laser beam L moves scanningly. In FIG. 3, the laser beam LA is shown as that at a certain instance. The laser beams LB and LC are shown as at the next instances in this order. The beams LA, LB and LC are transmitted through the plate 15 (or 16) as LA1, LB1 and LC1. Additionally, a part of each of the beams LA, LB and LC is reflected by the opposing surfaces of the plate 15 (or 16) and then transmitted therethrough as shown by reference characters LA2, LB2 and LC2. The beams LA1, LB1 and LC1 are interfered with LA2, LB2 and LC2, respectively due to the optical path length difference therebetween. When the optical path length difference between the transmitting beam LB1 and the reflected beam LB2, for example, is m.lambda. (m is an integer, and .lambda. is the wavelength of the laser beam), those beams are strengthened. When, on the contrary, the optical path difference is (2 m+1/2).lambda., they are compensated.
When the laser beam deflects from the position shown by the beam LA to the position shown by the beam LC, the transmitting beam and the reflected beam are strengthened and compensated repeatedly to form a stripe pattern on the photosensitive drum 1.


Thermoplastic/thermosettable coatings or inks for glass, ceramic or other hard surfaces are provided. The coatings comprise a blend of epoxy resins and a curing agent for the blend which provides a latency period of about 30 minutes at the screening temperature for such composition. Additional components are added to the composition depending upon the desired use. The compositions are applied to the hard surface by a high temperature screening process and heat cured on the surface.

Decorative and functional coatings or inks for glass, ceramics and other hard surfaces normally range from a rigid solid to a semisolid at room temperature. Normally the products are heated to a temperature in the range of about 120.degree.-270.degree. F. to melt or soften them for application by any one of the standard ink or coating application methods. One preferred method is the use of a heated metal screen and a rubber squeegee in a high temperature version of the "silk screen process". Ceramic inks in thermoplastic carriers are commonly applied in this manner. Following application, the coating is subjected to curing. A critical requirement for a thermoplastic/thermosettable screen ink is that it have a sufficiently wide difference between the melting or softening point--which dictates the screen temperature--and the curing temperature to provide adequate working time on the screen. If that difference is too small, the ink may be unstable on the screen and begin to gel or cure prematurely.
Conversely, if the system is formulated to be so latent that very long cure times and high temperatures are required for curing, the system is impractical for high speed production equipment and/or the thermal stability of the pigments and other additives employed becomes a concern. As employed herein the term "thermoplastic/thermosettable refers to materials which initially melt or soften upon raising the temperature above room temperature and which, upon further raising of the temperature begin to harden or set as a result of curing. By "latency period" is meant the period during which the thermoplastic/thermosettable composition can be maintained at a given temperature before becoming hardened or set.
For coating or ink compositions such as those of this invention, the choice of the curing agent(s) employed is important since the latency period must be, for example, several months at room temperature and up to several hours at temperatures of about 140.degree. to about 270.degree. F. In the present invention, certain specified curing agent(s) are employed.

Thermoplastic/thermoset table coatings or inks for glass ceramic and other hard surfaces


A compact, enclosable plant for producing hot mix asphalt from various ingredients, including recycle asphalt pavement ("RAP"). The system includes an inclined rotary drum, a burner assembly for generating a hot gas stream within the drum; a baghouse, exhaust blower, and stack mounted above the drum for reclaiming entrained particulate matter; an auger arrangement for returning the reclaimed particulate matter to the: and a supporting frame. The baghouse has a lower chamber for collecting the reclaimed particulate matter and for serving as a primary hopper for certain of the various ingredients. A plurality of preferably rectangularly shaped storage and loadout silos for containing certain of the ingredients and the hot mix asphalt, and conveyors for conveying the certain ingredients and hot mix asphalt to and from the storage and loadout silos, and to a bypass chute for direct loading on transport vehicles. The system is compact such that lengths of conveyors and ducting interconnecting the baghouse and drum can be minimized, and such that the system can be enclosed to minimize noise and odor pollution and to provide an esthetic appearance. The system may be configured in either a counterflow configuration or a parallel flow configuration.

1. Field of the Invention
The present invention relates generally to a plant for producing asphalt products and, particularly, without limitation, to such a plant comprising a rotary drum dryer/mixer for producing hot mix asphalt and a baghouse for removing airborne contaminants from a hot gas stream discharged from the rotary drum.
2. Description of the Related Art
Asphalt plants for producing hot mix asphalt products are notorious for generating greater or lesser amounts of environmental pollution, including thermal, noise, odor and esthetic pollution. Although significant improvements have been realized in attempts to reduce and contain such pollution below certain allowable minimums, sufficient residual pollution remains whereby asphalt plants are generally perceived to constitute undesirable nuisances in the community, particularly near residential developments.
As indicated, part of the problem with asphalt plants is esthetic pollution. The visual impact provided by a big, ugly plant having various components spread out horizontally from each other and interconnected by various conveyors and ductwork is anything but attractive. In addition, the interconnecting conveyors and ductwork enhances the opportunities for undesirable odors, etc., to be released to the surrounding environment even though such leakages may be sufficiently diluted to remain below allowable minimums.
What is needed is a system for producing hot mix asphalt wherein the various components can be arranged relative to each other such that the interconnecting conveyors and ductwork can be minimized to thereby reduce or eliminate opportunities for leakage of various pollutants, and such that the system can be compactly configured and enclosed to thereby provide a more esthetic and pleasing appearance to the surrounding community.


A SQUID includes a substrate and a superconducting current path of a patterned oxide superconductor material thin film formed on a surface of the substrate. A c-axis of an oxide crystal of the oxide superconductor material thin film is oriented in parallel to the surface of the substrate.

1. Field of the Invention
The present invention relates to a superconducting quantum interference device (called "SQUID" in the specification), and more specifically to a novel SQUID having a superconducting current path constituted of an oxide superconductor material.
2. Description of Related Art
Of electronic devices utilizing the superconduction phenomenon, a SQUID is one of the devices most advanced in reduction into practice.
The SQUID is formed of a closed-loop superconducting current path having one or two weak links inserted thereto. A superconducting current flowing through the closed-loop superconducting current path cannot exceed a critical current of the weak link portion, and therefore, a current density in the closed-loop superconducting current path is extremely small. Accordingly, the momentum of cooper pairs existing in the superconducting current path is small, and on the other hand, the wavelength of a corresponding electron wave is extremely long. As a result, it can be regarded that the phase is the same in different portions within the superconducting current path. However, if a magnetic field is applied to this superconducting current path, a phase difference occurs in the superconducting current path. By utilizing this unique phenomenon, the SQUID can be used as a magnetic sensor having an extremely high sensitivity.
In fact, the SQUID has already actually been used not only in a fundamental measurement field for a magnetization meter, a NMR, a magnetic thermometer, etc. but also in a medical field for a magnetic cardiograph, an electroencephalograph, a magnetic tracer, etc., and in the field of earth science for a geomagnetism observation, an earthquake prediction, a resource prospecting, etc.
On the other hand, the superconducting material known in the prior art had become a superconductor only at an extremely low temperature not greater than a liquid helium temperature, and therefore, it had not been considered to practically utilize the superconducting material. However, since it was found in 1986 that compound oxide sintered material such as (La, Ba).sub.2 CuO.sub.4 or (La, Sr).sub.2 CuO.sub.4 are a superconductor material having a high critical temperature (Tc), it has been confirmed from one to another than a compound oxide such as a Y--Ba--Cu--O type compound oxide or a Bi--Ca--Sr--Cu--O type compound oxide shows a superconduction characteristics at an extremely high temperature. This material showing the superconduction characteristics at the high temperature permits to use an inexpensive liquid nitrogen for a cooling medium, application of superconduction technique has abruptly been put under study as an actual matter.
Therefore, if the oxide superconductor is used in the SQUID, it is expected to further promote spread of the SQUID which has been actually used in the above mentioned various fields. However, the SQUID actually formed of the oxide superconductor has internal noise generated by the SQUID itself, and therefore, can have only a substantially low sensitivity. When the SQUID is used as a sensor, it is possible to eliminate external noises by using a high degree of gradiometer, but it is very difficult to eliminate internal noises. Because of this, it is difficult to use the SQUID composed of an oxide superconductor, as a low-noise high-sensitivity sensor.

Superconducting quantum interference device formed of oxide superconductor thin film


Handbags, particularly an expandable valise having an expandable body portion so as to accommodate variously sized contents. The valise includes the combination of a rigid batten adjustably supported on its top and pairs of inner and outer adjusting-reinforcing straps which encircle the entire valise, as well as the batten so as to contain or stabilize the body portion and its contents.

1. Field of the Invention
This invention relates to portable and collapsible valises wherein an expandable configuration may be adjustably conformed to varying content volume and stabilized against distortion as in traveling. Stability is achieved by the combination of an adjustable batten, and pairs of inner and outer adjusting straps which vertically encircle the entire body portion of the valise. In the preferred configuration, a pair of inner vertical reinforcing straps extends rear to front around the bottom of the valise. In addition, a pair of outer vertical reinforcing straps which are disposed in parallel and abutting relation relative to the pair of inner straps, extends fully around the valise body portion and, also, secures the top by extending through a substantially rigid, yet adjustable batten. Whereas numerous valise and pouch containers have been devised with reinforcing straps engaging the exterior thereof, no such combination of adjustable batten and pairs of inner and outer reinforcing adjusting straps has been devised to stabilize an expandable valise, irrespective of its variously sized contents.
2. Prior Art
STEIN--U.S. Pat. No. 1,638,753 PA1 STANSBURY--U.S. Pat. No. 1,931,547 PA1 SEAMAN--U.S. Pat. No. 4,148,347 PA1 BLAKE--U.S. Pat. No. 179,945 PA1 Germany (WERBE)--20989 (1983) PA1 Great Britain (ORTWEILER)--27567 (1908)

Expandable valise with vertical stabilizing straps


A reticle for use in a photolithography process for exposing a photoresist layer in the production of a component which is formed from a plurality of adjacent exposed areas. The reticle includes an exposure aperture adapted to allow light to pass through the reticle, a patterned area within the exposure aperture which defines at least part of the functional design of the component, and one or more “stitching” structures located close to one or more of the edges of the exposure aperture. The “stitching” structures are arranged to create “stitching” marks on the photoresist, which can be used to determine whether the adjacent exposed areas have been accurately positioned.

In photolithography techniques features are usually printed by passing light through a "reticle", which acts as a mask and is typically formed from glass printed with chrome patterns. In order to print lines the reticle is provided with slits which allow the light to pass through onto the photoresist (a photosensitive layer used to coat silicon in photolithography techniques). The exposed areas of the resist are removed by applying a developer, and the wafer is then etched by applying a suitable chemical.
In the lithographic stages of an IC (Integrated Circuit) or MEMS (Micro Electrical Mechanical Systems) process, light is transmitted through a mask (sometimes called a reticle) to form patterns on a wafer by means of photoresist and its developer. A common method of defining patterns on a wafer is by means of a step-and-repeat system which involves use of a reduction lens and a mechanical stage. The mechanical stage supports the wafer, and is arranged to move it accurately over given distances. Maximum field sizes on the wafer of reduction lenses (usually 5× reduction) are of the order of 20 mm square so that by means of accurately moving the wafer stage a series of many identical fields can be defined. The size of each circuit component exposed by the reticle at any given time may be much smaller than the field size, which is simply the maximum size that can be exposed at any one time. Contemporary stage technology requires that the registration of patterns to those on an underlying layer can be achieved by global alignment only whereby the whole of the wafer is aligned at 2 or 3 points to marks on the mask. Thereafter, because stage accuracy is very good, of the order of 100 nm over a distance of 22 mm, the series of fields is defined, after the global alignment, by "blind" stepping the stage, that is by moving the stage without further alignment.
Sometimes circuits require an area greater than the maximum field size available in a step-and-repeat system for correct operation. This situation provides increased demands for lithography but can be achieved by means of placing multiple elements on the mask, some of which are used more than once, and then "stitching" together the elements formed by each of the exposures. There is of course no literal "stitching", but the word "stitching" is used to refer to the accurate positioning, or butting, of one exposure next to another.
The invention seeks to address the problem of ensuring accurate "stitching" between different adjacent exposed areas.

Exposure positioning in photolithography


A computer program product for determining buying online and picking up in store. A computer receives from a shopper a request for buying online and picking up in store. The computer parses stores carrying an item purchased online and connections of the shopper in a social network. The computer provides the shopper with a list of one or more connections for picking up the item for the shopper. The computer sends to one of the one or more connections a token for picking up the item and information of a store where the item is picked up, after the shopper chooses the one of the one or more connections for picking up the item. The computer sends to the shopper a notification, after the item is picked up by the one of the one or more connections for picking up the item.

The present invention relates generally to online commerce, and more particularly to computer-implemented intelligently determining buying online and picking up in store based on commute patterns of connections in a social network and store parameters.
There are two common scenarios for online shopping. In one scenario, items purchased online are shipped from stores; in another scenario, items purchased online are picked up in stores by online shoppers. Nowadays, buying online and picking up in store has been popular. Online shoppers purchase merchandise from stores' websites and pick up in selected stores. For buying online and picking up in store, a seller commits to an online shopper that an item purchased online is ready to be picked up in a specific store and at a specific time. Generally, a shopper inputs a zip code or a list of stores for pickup, and an ecommerce system calculates availability accordingly.

This patent is subject to a terminal disclaimer.

Intelligently determining buying online and picking up in store based on commute patterns of connections in a social network and store parameters

International Business Machines Corporation


Light sources that emit light having enhanced color spectrum characteristics are described. A color metric called the Lighting Preference Index (LPI) is disclosed that enables quantitative optimization of color preference by tailoring the spectral power distribution of the light source. In an embodiment, a lamp includes at least one blue light source having peak wavelength in the range of about 400 nanometer (nm) to about 460 nm, at least one green or yellow-green light source having peak wavelength in the range of about 500 nm to about 580 nm, and at least one red light source having peak wavelength in the range of about 600 nm to about 680 nm, wherein the lamp has an LPI of at least 120.

Reveal® is a trademarked term used by the General Electric Company to refer to light sources, such as a light bulb, having enhanced red-green color contrast lighting characteristics and enhanced whiteness relative to an unmodified incandescent or halogen light source. Reveal® incandescent and halogen bulbs filter light by placing a particular type of glass (namely, glass impregnated with neodymium (Nd) oxide) in front of the light emitted by the filament which absorbs some of the yellow light. The glass impregnated with Nd oxide causes a "depression" in the yellow region of the color spectrum, so that objects viewed under this light have an enhanced color contrast, especially red and green objects which are contrasted readily by an observer, such as a person in a room of a house. The removal of some yellow light also shifts the location of the chromaticity on the CIE color diagram to a point slightly below the blackbody locus, which generally creates the impression of whiter light to most observers.
The significance of yellow light and how it impacts the perception of color is illustrated in FIGS. 1A, 1B and 1C. FIG. 1A graphs the three color matching functions, or the chromatic response of a standard observer, for XYZ chromaticity. The perceived color of an object is determined by the product of the illumination source spectrum, the reflectance spectrum of the object, and the three color matching functions. These functions are related to the response of the photoreceptors in the human eye, and can be thought of as the perception of blue (102), green (104), and red (106) light. FIG. 1b plots the product of a standard incandescent spectrum with the color matching functions for blue (132), green (134), and red (136) responses. As can be seen, the green (134) and red (136) components overlap significantly and the peaks are only separated by 34 nm. FIG. 1c plots the product of a Reveal® incandescent spectrum with the color matching functions for blue (162), green (164), and red (166) responses. As can be seen, the green (164) and red (166) components are more distinct with a peak separation of 53 nm. This allows observers to more easily distinguish reds and greens with greater contrast and results in a more saturated appearance when yellow light is suppressed.
Spectrally enhanced lighting products have enjoyed decades of commercial success. Traditional color quality metrics or conventional measurements may not reward such enhanced lighting products, yet consumers often prefer them to their unaltered counterparts. With the advent of solid-state lighting (SSL), particularly the customizability of light-emitting diode (LED) spectra, it has become apparent that current metrics are inadequate to evaluate and reflect the quality of LED products. SSL light sources, for example LEDs or OLEDs may produce light directly from the semiconductor, e.g. a blue or red or other colored LED. Or the light may be produced by conversion of the high-energy light from the SSL, e.g. a blue or violet LED, by a down-converter such as a phosphor or quantum dot or other energy converting material. The range of peak emission wavelengths for semiconductors, and the range of the peaks and widths of the emission of down-converters have been extended by recent technological development to cover a nearly continuous range throughout the visible wavelengths (about 380 nm to about 750 nm), enabling broad flexibility in tailoring the visible spectrum in order to enhance color preference for an observer. For purpose of spectral tailoring, therefore, the term light source may mean any source of visible light, e.g. the semiconductor, or LED, or OLED, or the down-converter such as a phosphor or quantum dot, or a composite of several such light sources, or a system such as a lamp or luminaire or fixture comprising such light sources.
For nearly a half-century, the color rendering index (CRI) has been the primary method of communicating the color quality of a light source. However, its effectiveness is inherently limited due to its method of calculation, particularly when dealing with spectral power distributions (SPDs) containing steep slopes versus wavelength, as often seen with LEDs. The shortcomings of CRI are well documented, and a wide variety of alternative metrics have been proposed. However, alternative color quality metrics struggle to accurately quantify consumer preference of lighting products. Houser and colleagues provide a detailed overview and comparison of a large fraction of the various color quality metrics developed in "Review of measures for light-source color rendition and considerations for a two-measure system for characterizing color rendition", Optics Express, volume 21, #8, 10393-10411 (2013), authors K. W. Houser, M. Wei, A. David, M. R. Krames, and X. S. Shen. In general, the variety of metrics can be broken down into three broad categories pertaining to their intent and method of calculation: fidelity, discrimination, and preference. Fidelity metrics, which include CRI, quantify an absolute difference from a reference illuminant, regardless of whether the test illuminant is perceived as being better or worse, and without consideration to whether the reference illuminant is actually preferred by most observers. Discrimination metrics quantify the total area of color space that is renderable under the test illuminant, and are maximized at extreme levels of saturation and hue distortion. The many conventional color preference metrics have been developed to provide a quantitative measure of user color preference, but none provides a sufficient correlation to observer data, along with a target value to enable optimization of a light source, so that the metric can be used as a target parameter in a design optimization.
In general, it has been found that observers prefer an enhanced level of saturation, rendering colors more appealing. However, high levels of saturation, or shifts in hue, can result in unnatural rendering of colors and objects. For example, the Gamut Area Index (GAI) and the Gamut Area Scale (Qg), both of which are discrimination metrics, provide a very good correlation with observer preference up to some limit of color saturation, beyond which GAI and Qg continue to increase, while observer preference sharply declines. It therefore appears that some adjustment may be necessary to a color saturation metric such as GAI or Qg to better align it with observer preference. Furthermore, observers also tend to prefer light sources that appear whiter, driven by the color point of the illuminant relative to the Planckian (blackbody) locus, somewhat independent of the color saturation. As is generally recognized in the lighting industry, color preference cannot be adequately quantified by any single existing color metric. Several attempts have been published recently to combine two or more color metrics to better describe color preference. However, it does not appear that anyone has proposed a color preference metric that defines color preference with sufficient quantitative rigor to enable the optimization of the color preference of a light source by numerical tailoring of the spectrum. Even though the existing color preference metrics are quantitative, each is limited in some way to disqualify their use as an optimization parameter when designing a light source or a spectrum to achieve optimum color preference for a typical observer.
Some of the more well-known metrics in the color preference category include Flattery Index (Rf), Color Preference Index (CPI), and Memory Color Rendering Index (MCRI). All three of these metrics have "ideal" configurations for the chromaticity coordinates of eight to ten test color samples, and each quantifies the deviation from these target values. The flattery index was the first metric to target preference and used ten color samples with unequal weighting. However, in order to maintain similarity with CRI, the target chromaticity shifts were reduced to one-fifth of their experimental values, greatly reducing its impact. CPI maintained the experimental values for preferred chromaticity shifts, resulting in a better representation of color preference. However, it is somewhat limited in its selection of test color samples, using the same eight, unsaturated test colors as CRI. Unsaturated (pastel) test colors are incapable of evaluating the impact of a highly saturated light source. MCRI uses observers' memory to define the ideal chromaticity configuration of ten colors of familiar objects. Furthermore, none of the metrics above factor in the "whiteness", or color point, of the test source. To this point, authors J. P. Freyssinier and M. S. Rea, in "Class A color designation for light sources used in general illumination," Journal of Light and Visual Environment, volume 37, #2&3, pp. 46-50 (2013), recommended a series of criteria for "Class A Lighting", which places constraints on CRI (>80), GAI (80-100), and color point (near "white" line). While these conditions define a recommended design space, they cannot be optimized to prescribe a spectrum or light source that maximizes color preference, as there is no optimal value identified, and no weighting of the three characteristics recommended.
Solid-state lighting technologies such as LEDs and LED-based devices often have superior performance when compared to incandescent lamps. This performance can be quantified by the useful lifetime of the lamp, lamp efficacy (lumens per watt), color temperature and color fidelity, and other parameters. It may be desirable to make and use an LED lighting apparatus also providing enhanced color preference qualities.
Commercial lamp types (including incandescent, halogen, and LED) employing Nd-doped glass to absorb some of the yellow light from the spectrum emitted by the light source exist, which enhance the color preference relative to their counterpart lamps without the absorption by the Nd-doped glass. GE Lighting, and some other manufacturers, has products of each of these three types. The GE Lighting products have the Reveal® brand name.
Some special formulations of phosphor for compact fluorescent (CFL), linear fluorescent (LFL), and LED lamps are known to enhance the color preference relative to their counterpart lamps that employ standard phosphors. GE Lighting has products of each of the first two types, also under the Reveal® brand name. LED light sources of the third type are known, for example in grocery applications to enhance the colors of meats, vegetables, and produce (e.g. fruit).
Each of these existing light sources has employed either Nd-doped glass, or customized phosphors that reduce the amount of yellow light emitted by the light source in order to enhance color preference. However, none of these products achieves a level of color preference exceeding that of the decades-old GE Lighting Reveal® incandescent, and the other existing products. The Nd filter in these existing light sources is typically comprised of Nd2O3-doped glass, but in other embodiments the yellow filter may be comprised of one of several other compounds of Nd or of Didymium or other compounds that preferentially absorb yellow light, embedded in various matrix host materials, for example glass, crystal, polymer, or other materials; or by some other dopant or coating on the glass that absorbs preferentially in the yellow; or by the addition of any yellow absorber to any of the optically active components of the lamp or lighting system, such as a reflector or diffuser or lens, which may be a glass or polymer or metal or any other material that accommodates the yellow absorber. The exact peak wavelength and width of the yellow absorption will vary depending on the particular Nd or rare-earth compound and host material, but many combinations of Nd, Didymium and other rare-earth compounds and host materials are suitable substitutions for the combination of Nd2O3-doped glass, as are some other yellow filters. The Nd or other yellow filter may be in the shape of a dome enclosing the light source, or may be any other geometric form enclosing the light source, such that most or all of the light in the yellow range of wavelengths passes through the filter.


A bread slicer is provided, which includes a receiving area for receiving a loaf of bread; a return area for delivering sliced bread; and a path along which the bread moves from the receiving area to the return area. The path includes a substantially downwardly inclined surface extending from the rear of the receiving area to the return area. The slicer has a slicing element for slicing the bread as it passes from the receiving area to the return area; and a guard for preventing access to the slicing element from the receiving area. The guard is fixed relative to a guide mechanism, the guide mechanism being movable along a path divergent from the inclined path to advance the loaf along the path.

Bread slicing machines are commonplace in most bakeries and retail outlets. In many commercial operations, the loaves of bread are sliced prior to wrapping by an apparatus having either a series of FIG. 8 bands of blades or through reciprocating blades which allow multiple slices to be cut at once or by sickle slicing one slice at a time using a single blade. In current slicer machines, the operator places one or more loaves on a platform and the loaves are moved from one side of the machine through the blades to the other side of the machine by mechanical devices or by gravity. Depending on the feed mechanism, the platform can be inclined or flat.
In bakeries and retail outlets, there is often a shortage of available space and so the space allocated to a slicing machine is limited. Therefore a bread slicer which occupies space efficiently without compromising safety is desirable.
In some versions of reciprocating bread slicers, the reciprocating blades are exposed or easily accessed by the operators exposing the operators of the bread slicers to the risk of injury by contact with moving or stationary blades.
In other versions of reciprocating bread slicers where the reciprocating frame is housed within an enclosure, there is still a risk that the operator's hands can come into contact with the stationary reciprocating blades during loading of the loaves of bread onto the supporting table.
The area of greatest working danger is the sharp side of the reciprocating blades of a bread slicer, and although many forms of guard exist, most only guard against the operator contacting moving blades. The blades being high in number and very sharp, are still a high risk even when stopped.
Objects of the present invention include to provide a safer, more space efficient slicer or at least provide an alternative in the market place.


Ribs serving as reinforcing members of the hub pawls provided to the inner peripheral surface of a cylindrical hub around which a tape is wound can be formed in a simple shape using an electric discharge electrode. A hub comprises plural hub pawls projected from the inner peripheral surface of a hub hole of a tape winding hub, and ribs each of which has a slant surface and is provided to the base portions at both the sides in the hub rotational direction of the hub pawl, wherein the slant surface of the rib is formed in a convex three-dimensional shape (arcuate shape) which is inclined with respect to the cylindrical hub pawl.

1. Field of the Invention
The present invention relates to a tape cartridge, and more particularly to an enforcing rib provided to a hub pawl of a tape winding hub.
2. Description of the Related Art
As shown in FIG. 1, a tape cartridge in a prior art is constructed so that plastic (generally, high-impact polystyrene) hubs 12 around which a tape 11 is wound are freely rotatably located on respective driving shaft insertion holes 13 at the right and left sides in a main body case 10. Each of both the ends of the tape 11 is hooked and coupled to a part of each outer periphery of the right and left hubs 12 by a cramping piece 14, and the tape 11 is drawn from one hub 12 to the front face of the main body case 10 and wound by the other hub 12.
The hub 12 has a hub hole 15 at the center thereof, and a plurality of hub pawls 16 are integrally projected from the inner peripheral surface of the hub hole 15 in the central direction so as to be spaced from one another at predetermined intervals.
The hub pawl 16 is designed in a substantially cylindrical shape of about 1.5 mm in diameter and about 1 mm in length, and it is extremely smaller as compared with the size, thickness, etc. of the overall hub 12. Therefore, fast feeding or rewinding operation by a recent tape recorder imposes a large impact load on the hub pawls 16, and excessive stress is applied to the bases of the hub pawl 16, so that such a problem as damage or the like may occur. Particularly since there frequently occurs such a case that a user carries a tape cartridge on the road when the user goes outdoors, when a drop impact or the like is applied to a tape cartridge while the tape cartridge is accommodated in an accommodation case, a hub rotation stop member at the accommodation case side and the hub pawls 16 collide against each other, and the hub pawls 16 may be damaged at the base portions thereof.
JP-A-60-51685U previously proposed a device of a countermeasure of preventing the damage of the hub pawls 16 as described above. In this device, as shown in FIG. 2, the base portion of the hub pawl 16 in the rotational direction is provided with ribs 18 each comprising a rounded R-surface 17. By forming the R-surface 17 as described above, the concentration of the excessive stress due to the impact load which is applied to the hub pawls 16 in the rotational direction can be avoided, and the strength can be enhanced, so that the damage preventing effect of the hub pawls 16 can be expected.
However, in case of the hub pawl 16 having the ribs 18 having the R-surface 17 as described above, when the hub 12 is manufactured, it is necessary to process the place of a die corresponding to the R-surface portion of the hub pawl in a minute and complicated three-dimensional shape, and it is difficult or impossible to perform the processing by using equipment such as an electric discharge machine or the like. Therefore, there is a problem that the cutting work must be manually carried out on the place.
In order to solve this problem, there is known JP-A-62-80280U. In this device, as shown in FIGS. 3 and 4, the rib 19 provided to the base of the hub pawl 16 is designed in a simple two-dimensional shape to have an R-surface 20. That is, as shown in FIG. 4, the rib 19 has the R-surface 20 provided in the rotational direction of the hub 12, and side surfaces 22 which are crossed to the R-surface 20 through the ridgelines at both the sides of the R-surface 20, and the R-surface 20 is designed to have the same curvature in the pawl peripheral direction W. The rib 19 of the hub pawl 16 is designed in such a two-dimensional simple shape as described above, so that the electric discharge machining to form a die can be performed and the die processing can be facilitated.
However, even when the R-surface of the rib provided to the hub pawl in the prior art described above is designed in a simple two-dimensional shape, the shape of an electrode required for the electric discharge machining to form a die must be processed in conformity with the shape of the rib. Therefore, there is a problem that the shape of the electrode is complicated.
Accordingly, there is a problem that a rib must be designed in such a shape that an electrode for the electric discharge machining used to process a die for the rib provided to the hub pawl is simple.