Abstract: A production method of a heat-treated steel member includes the steps of: shaping a steel material of low-carbon boron steel containing about 0.05-0.30% carbon by weight into a predetermined configuration to bc a shaped material; and heat-treating the shaped material, said heat-treating, includes quench-hardening only.

Abstract: Universal optical fiber connectors and their basic plugs, wherein the optical fiber connectors have some common elements for their connector-functions to permit an installation of optical fiber into one of the different type connectors for establishing their connection more easily and to facilitate a tuning operation with positioning key maintaning the same direction between eccentricity of the fiber core and the key. The basic plug has a ferrule, a spring element, and a cylindrical tube. The spring element is positioned between a ferrule and a cylindrical tube, so that it exerts forces toward them in an axial direction. The ferrule has a common dimensional structure for securing an optical fiber and has a shape enabling the connection to any one of various kinds of housing members. Thus, the basic plug connects separate optical fibers together through the housing member.

Abstract: A universal optical fiber connector comprises a ferrule for supporting an optical fiber and having an axis extending in an axial direction of the ferrule, a biasing member comprised of a synthetic elastic material for biasing the ferrule in the axial direction, and a securing member for securing the biasing member between the securing member and the ferrule. A connecting member is adapted to receive the ferrule for connection to another ferrule through the connecting member.

Abstract: A method for heat-treating a hollow cylindrical workpiece includes quench-hardening including a first step and a second step. In the first step, during continuously conveying the workpiece in a horizontal direction without a space between adjacent workpieces, an entirety of the workpiece is subjected to induction-heating conducted from an outside surface of the workpiece only, and a temperature of the workpiece is made uniform before the workpiece reaches a cooling portion spaced from a heating portion. Then, cooling the workpiece is initiated before the temperature of the workpiece falls to Ar3 temperature and an entire cross-section of a wall of the workpiece is quench-hardened. In the second step, during continuously conveying the workpiece in the horizontal direction, induction-heating is conducted only to an outside portion of the workpiece, the induction-heating being conducted from the outside surface only.

Abstract: Universal optical fiber connectors and their basic plugs, wherein the optical fiber connectors have some common elements for their connector-functions to permit an installation of optical fiber into one of the different type connectors for establishing their connection more easily and to facilitate a tuning operation with positioning key maintaining the same direction between eccentricity of the fiber core and the key. The basic plug has a ferrule, a spring element, and a cylindrical tube. The spring element is positioned between a ferrule and a cylindrical tube, so that it exerts forces toward them in an axial direction. The ferrule has a common dimensional structure for securing an optical fiber and has a shape enabling the connection to any one of various kinds of housing members. Thus, the basic plug connects separate optical fibers together through the housing member.

Abstract: An image forming apparatus which includes both a front cover and a side cover which must be opened to properly access an area where a paper jam may occur. The side cover includes an extending portion protecting board which extends into an area covered by the front cover. The protecting board prevents access to internal elements of the image forming apparatus which an operator may attempt to access if a paper jam occurs, without also opening the side cover. Thereby, an operator is required to properly open both the front cover and the side cover to address a paper jam situation.

Abstract: In an adhesive injection pipe for injecting an adhesive X into a rear end through hole of a ferrule main body, a first stopper portion for positioning in the ferrule main body and a second stopper portion to be engaged with an injecting end of an injector for injecting an adhesive are provided on a cylindrical member having a front end portion to be fitted in the rear end through hole, and a handle member is formed at a rear end of the cylindrical member.

Abstract: A ferrule for optical connectors which is of funnel type comprising a ferrule body, containing a small-diameter hole and a large-diameter hole having a larger diameter than the small-diameter hole, the small-diameter hole and the large-diameter hole being formed so as to allow an optical fiber to pass therethrough and communicate with each other, the ferrule further comprising a buffering hole having a diameter which is larger than that of the small-diameter hole but smaller than that of the large-diameter hole, the buffering hole being formed between the small-diameter hole and the large-diameter hole and containing groove of concave and convex pattern on the internal surface of the buffering hole. The ferrule body further contains three lines of protrusions extending along the axial thereof, which are formed on the internal surface of the large-diameter hole.

Abstract: An abrasive sheet containing, on at least one surface thereof, a layer of a nonwoven fabric comprising not less than 80% of fibers having a fiber diameter of 10 .mu.m or less, the nonwoven fabric being selected from a group consisting of an entangled nonwoven fabric and a melt-blown nonwoven fabrics.

Abstract: A method for assembling an optical fiber connector comprises providing a ferrule having a first end portion, a second end portion and a bore extending through the first and second end portions. A first open end of a tubular member is fitted over the first end portion of the ferrule without a gap therebetween. An adhesive agent is then injected into the bore of the ferrule through a second open end of the tubular member. The tubular member is thereafter removed from the second end portion of the ferrule, and an optical fiber is inserted into the bore of the ferrule to thereby fix the optical fiber in the bore of the ferrule.

Abstract: There is disclosed an asphalt extracting apparatus of the Soxhlet type in which a solvent evaporated from a flask is condensed by a cooling device and then dropped into the inside of a filter device such that asphalt in an asphalt mixture inside the filter device is extracted through the filter device. With the flask and the filter device covered with a thermally insulating case, the flask and the filter device are heated and thermally insulated by the heat of a gas burner. To lower the boiling point of the solvent in the flask, each of the flask, the filter device and the cooling device is decompressed by a decompression device.

Abstract: A navigation apparatus stores road data which are formed by a network of internally stored road links and traveling costs corresponding to the respective ones of the internal road links. When the navigation apparatus receives traffic information corresponding to a specific external road link which is set for communication of traffic information, the apparatus identifies one or more internal links or portions thereof corresponding to the external link for which traffic information has been received, and the stored traveling costs are updated, on the basis of a conversion table. The traveling cost for an internal road link corresponding to a specific external link which is closed to traffic is updated to ".infin.". The apparatus searches for and identifies a route between an origin and a destination based on the updated traveling costs and the network of the road links. The internal links do not need to correspond directly to the external links, but rather may include more branch points for example.

Abstract: A cleaning sheet for a fuser roll, wherein an average diameter of fibers constituting said cleaning sheet is not more than 14 .mu.m; a layer containing not less than 30% by weight of softening fibers which soften at a temperature higher than an ambient temperature of the fuser roll, but lower than a temperature which is 100.degree. C. higher than a surface temperature of the fuser roll is contained; and the cleaning sheet is bonded with adhesive fibers having a fiber diameter of not more than 20 .mu.m; a cleaning member for a fuser roll, having the above cleaning sheet; a supply shaft around which the cleaning sheet is wound; and a take-up shaft to which one end of the cleaning sheet is fixed; and a cleaning apparatus for a fuser roll, having the above cleaning member; and a pinch member for pressing the cleaning sheet wound off from the supply shaft to a fuser roll and conveying the cleaning sheet to the take-up shaft.

Abstract: In representing a depth of field in a camera, the depth of field is displayed on the basis of the magnitude of a field depth feeling Df which corresponds to human feeling. The field depth feeling Df is obtained by processing at least one of a depth of field on calculation, an object distance, a lens hypen-focal length, a diameter of permissible circle of confusion, a lens aperture value and a lens focal length.

Abstract: A digital time base corrector in which a memory for correction of a time base is commonly used as a memory for correction of a drop-out and a signal process to a video signal which is replaced by a drop-out compensation is made unnecessary. The corrector has an image memory having a capacity to store the digital video signal by only two horizontal scan periods. When a drop-out occurs in the reproduction video signal, the writing operation into the image memory is inhibited. In the portion in which the drop-out occurred, the video data before about 2 H is read out in place of such a portion and the drop-out compensation is executed. Therefore, the drop-out portion is replaced by the video data of the same phase.

Abstract: A digital time base corrector uses a memory with a reduced storage capacity, to reduce the cost. Absolute value data of an amplitude and polarity data of a burst signal in a color video signal are written into a memory every horizontal scan period. A signal in which a sync signal interval, a pedestal level interval, and a burst signal interval in the color video signal are eliminated is written as image data into the memory. The absolute value data, polarity data, and image data are read out from the memory. Burst signal data is reproduced on the basis of the absolute value data and polarity data. By inserting the burst signal data, sync signal data, and pedestal level data into the image data, a color video signal is reproduced.

Abstract: A navigation system for a vehicle comprises a central processing unit for executing a plurality of programs including a navigation program and a transmitting program, and an internal nonvolatile storage device electrically connected to the central processing unit through an inner bus and storing therein the transmitting program. The navigation system further comprises an external storage device electrically connected to the inner bus through an interface unit and storing therein the navigation program. The central processing unit is initially operated to execute the transmitting program to read the navigation program from the external storage device and store the read navigation program in the internal nonvolatile storage device, and subsequently operated to repeat the execution of the navigation program stored in the internal nonvolatile storage device to provide a vehicle driver with navigation information including the current location of the vehicle.

Abstract: In representing a depth of field in a camera, the depth of field is displayed on the basis of the magnitude of a field depth feeling Df which corresponds to human feeling. The field depth feeling Df is obtained by proccesing at least one of a depth of field on calculation, an object distance, a lens hypen-focal length, a diameter of permissible circle of confusion, a lens aperture value and a lens focal length.

Abstract: A digital time base corrector, when using a memory whose storage capacity is reduced to a value of about 1H of the video signal, can maintain an interleave relation between a luminance signal and a color signal of a video signal even when the writing operation into a memory is delayed by a jitter included in the demodulated video signal. When the read address is advanced from the write address in each of an image data memory and a subcarrier phase memory in one horizontal scan period, a discrepancy occurs between the polarity data read out from the subcarrier phase memory and the proper polarity data held in latch means. When such a discrepancy is detected, the color phase of the read-out image data is inverted. In starting the data reading operation for a new horizontal scan period, if it is detected that the operating mode has not shifted to the data writing operation for the new horizontal scan period, the color phase of the read-out image data is inverted for the new horizontal scan period.

Abstract: A digital time base corrector which can perfectly eliminate residual errors. A sync clock signal whose phase is synchronized with a time base fluctuation included in a reproduction video signal is formed in accordance with at least one of the horizontal sync signal and the color burst signal which are separated from a reproduction video signal. The sync clock signal is phase-modulated in accordance with a burst error signal indicative of the time base fluctuation of the color burst signal in a period of time other than the generating period of time of at least the color burst signal in the reproduction video signal, thereby obtaining a write clock signal of the image memory.