Abstract: An optical deflection element for splitting light rays in accordance with a wavelength of incident light, includes a photonic crystal having an entrance end face and an exit end face, and having a refractive index which periodically changes depending upon positions thereof. The optical deflection element includes a region in which a propagation angle &thgr;C of the incident light within the photonic crystal changes in accordance with the wavelength of the incident light having entered at an incident angle &thgr;IN into the entrance end face, and a relationship among a wavelength &lgr; of the incident light in vacuum, a lattice constant A of the photonic crystal, the incident angle &thgr;IN and the propagation angle &thgr;C satisfies (∂&thgr;C/∂(A/&lgr;))/(∂&thgr;C/∂&thgr;IN)>10.

Abstract: An image forming apparatus including an image carrier having a conductive support, at least a photoconductive layer formed on the conductive support, and a surface protection layer formed on the photoconductive layer and including a charge injection layer. Also included is a charging member for charging the image carrier in contact with the surface protection layer when applied with a voltage, and a developing unit for developing a latent image formed on the image carrier with toner to thereby produce a corresponding toner image. Further, the surface protection layer has a diamond-like carbon structure or an amorphous structure containing hydrogen, the developing unit develops the latent image with a magnet brush formed by magnetic particles for development, and the charging member includes magnetic particles for charging having a mean particle size smaller than a mean particle size of the magnetic particles for development.

Abstract: A fixing device for an image forming apparatus of the present invention includes an endless belt passed over a plurality of members for conveying a sheet in contact with a toner image carried thereon. A pressing member faces the above members with the intermediary of the belt. A first member, which is one of the plurality of members, constitutes a heating member for heating the belt. A second member, which is another one of the members, faces the pressing member with the intermediary of the belt. A third member, which is another one of the members, constitutes a stationary member facing the pressing member with the intermediary of the belt. The pressing member and first member and the pressing member and second member respectively form a first and a second nip therebetween. The toner image on the sheet is fixed by being sequentially conveyed via the first and second nips.

Abstract: An image forming apparatus of the present invention includes a fixing device for fixing a toner image formed on a recording medium. A heat source is applied with power for generating heat to thereby heating the heating device. A drive circuit includes a storage capable of being selectively charged or discharged and a charger for charging the storage by being supplied with power from a commercial power supply. A discharging device discharges the storage in a non-use mode in which the apparatus is not used.

Abstract: An image forming apparatus includes a photoconductive element including a conductive support rotatably supported and a charge injection layer and a surface protection layer sequentially laminated on the conductive support. A charger includes a conductive body for injecting, when a preselected voltage is applied thereto, a charge in the charge injection layer in contact with the surface protection layer. A writing unit exposes the charged surface of the photoconductive element imagewise to thereby locally vary the potential deposited on the photoconductive element and electrostatically form a latent image. A developing unit develops the latent image to thereby produce a corresponding toner image. The toner image is transferred from the photoconductive element to a recording medium.

Abstract: At startup operation of a fixing device, a standby period during which a fixing belt and a pressure roller are heated until they reach a respective predetermined target temperature is shortened by heating the fixing belt to a temperature which is higher than the target temperature. In the fixing device, the fixing belt is spanned around an opposing roller and a heating roller. A pressure roller is provided in press-contact with the opposing roller via the fixing belt. A heater heats the fixing belt and the pressure roller so that temperatures of the fixing belt and the pressure roller reach a target temperature suitable for fixing a toner image. A recording material is conveyed through the rotating fixing belt and pressure roller to fix the toner image onto the recording material by heat and pressure.

Abstract: An image forming apparatus includes a photoconductive element including a conductive support rotatably supported and a charge injection layer and a surface protection layer sequentially laminated on the conductive support. A charger includes a conductive body for injecting, when a preselected voltage is applied thereto, a charge in the charge injection layer in contact with the surface protection layer. A writing unit exposes the charged surface of the photoconductive element imagewise to thereby locally vary the potential deposited on the photoconductive element and electrostatically form a latent image. A developing unit develops the latent image to thereby produce a corresponding toner image. The toner image is transferred from the photoconductive element to a recording medium.

Abstract: An optical element has a small reflection loss of light on a boundary surface between a photonic crystal and the normal medium. The optical element includes: a normal medium region having a first refractive index; a photonic crystal region having a refractive index which is changed periodically depending upon a position thereof, the photonic crystal region having as an averaged refractive index a second refractive index different from the first refractive index; and an intermediate region interposed between the normal medium region and the photonic crystal region, the intermediate region having a refractive index which is gradually changed from the first refractive index to the second refractive index.

Abstract: A fixing apparatus includes a fixing member to be heated and a pressure-contacting member for pressure contacting the fixing member. The fixing apparatus directs and conveys a recording member through a nip formed between the fixing member and pressure applying member in such a manner that a toner image carried on a recording member contacts the fixing member in order to be fixed thereto with heat and pressure. The fixing apparatus is configured to direct a tip margin of the recording member toward the pressure applying member across a virtual linear extension line drawn from a downstream end to upstream end of the nip when only the tip margin exits from the nip. A fixing member side separation device may be separately provided from the surface of the fixing apparatus so as to separate the recording member exiting from the nip. A gap formed between the downstream end of the nip and the tip of the fixing member side separation device is set smaller than the width of the tip margin.

Abstract: An optical element has a small reflection loss of light on a boundary surface between a photonic crystal and the normal medium. The optical element includes: a normal medium region having a first refractive index; a photonic crystal region having a refractive index which is changed periodically depending upon a position thereof, the photonic crystal region having as an averaged refractive index a second refractive index different from the first refractive index; and an intermediate region interposed between the normal medium region and the photonic crystal region, the intermediate region having a refractive index which is gradually changed from the first refractive index to the second refractive index.

Abstract: An image forming apparatus includes a photoconductive element including a conductive support rotatably supported and a charge injection layer and a surface protection layer sequentially laminated on the conductive support. A charger includes a conductive body for injecting, when a preselected voltage is applied thereto, a charge in the charge injection layer in contact with the surface protection layer. A writing unit exposes the charged surface of the photoconductive element imagewise to thereby locally vary the potential deposited on the photoconductive element and electrostatically form a latent image. A developing unit develops the latent image to thereby produce a corresponding toner image. The toner image is transferred from the photoconductive element to a recording medium.

Abstract: At startup operation of a fixing device, a standby period during which a fixing belt and a pressure roller are heated until they reach a respective predetermined target temperature is shortened by heating the fixing belt to a temperature which is higher than the target temperature. In the fixing device, the fixing belt is spanned around an opposing roller and a heating roller. A pressure roller is provided in press-contact with the opposing roller via the fixing belt. A heater heats the fixing belt and the pressure roller so that temperatures of the fixing belt and the pressure roller reach a target temperature suitable for fixing a toner image. A recording material is conveyed through the rotating fixing belt and pressure roller to fix the toner image onto the recording material by heat and pressure.

Abstract: In an optical element, a propagation direction of incident light beam is largely changed and the direction-changed light beam is derived in a desirable direction without increasing a dimension and manufacturing cost thereof. The optical element includes photonic crystal having a refractive index which changes periodically depending on a location of the photonic crystal, wherein an angle defined between a first end face and a second end face thereof is determined in such a manner that a light beam incident upon the first end face at a predetermined incidence angle and having a predetermined wavelength is emitted from the second end face in a desirable direction.

Abstract: A welding apparatus for welding a trailing end of a preceding strip and a leading end of a subsequent strip including a shear device for cutting them in parallel and a back bar device for supporting the ends of the strips. Provision is made to detachably connect the shear device and the back bar device and move them along a common rail between the strip ends.

Abstract: A method and apparatus for flash welding are disclosed wherein a first predetermined voltage is applied between a pair of workpieces to be welded to generate flashes therebetween, and a second predetermined voltage lower than the first predetermined voltage is then applied between the workpieces to maintain fine flashes when the temperature of weld surfaces of the workpieces has reached a predetermined temperature. The workpieces are upset when the total number of flashes has reached a predetermined value. The pressure welding is maintained with an upsetting pressure sufficient to upset the workpieces and slightly higher than a pressure at which the workpieces are deformed near their recrystallization temperature until the temperature of weld surfaces has decreased to lower than the recrystallization temperature. The applied voltage and the upsetting pressure are controlled in accordance with the weld progress.

Abstract: A welding apparatus comprises a pair of clamping devices for clamping the workpieces to prevent slip under applying significantly large force to the butting surfaces for the butt welding operation and a pair of electrode tables for feeding a welding current. The welding apparatus need not comprise a step gauge bar nor an auxiliary clamp in order to set the projecting degree.

Abstract: In a flash welding apparatus, different length guides and driving devices thereof are formed on lower parts of an inlet side electrode table and an outlet side electrode table and the electrode tables and a compact rotary shear unit are arranged in the direction perpendicular to a strip line when both of the electrode tables are approached and one of the guides is commonly used as a guide for shifting a flash trimmer lower unit and a guide is formed on one of the upper electrode frames of the electrode tables so as to shift a flash trimmer upper unit and the rotary shear unit of the inlet side electrode table and the rotary shear unit of the outlet side electrode table and a pair of the upper and lower trimmer units are aligned in the plan view.

Abstract: A rectangular waveform voltage is applied between electrodes for welding by using a variable voltage-variable frequency type inverter as the power source for welding whereby the local short-circuit between workpieces can be immediately changed to the flash whereby the fine flash can be continuously generated to remarkably improve the quality of the welded part, and the voltage control can be attained without changing the voltage waveform.

Abstract: A flash and upset material formed in a flash welding operation can be removed by a machining of the flash and upset material for a short time after the welding operation by providing a workpiece clamping function by a main clamp and providing a welding current feeding function by an electrode table. The main clamp is heavy whereas the electrode table is light so as to be easily movable, whereby the electrode table in the light weight can be backwardly shifted for a short time after the welding operation and a space for inserting a tool holder equipping with a tool for machining a flash and upset material, is formed near the welded line. Since the flash and upset material can be machined during the time maintaining the softness of the flash and upset material at relatively high temperature for a short time, the machining can be attained by only pair of tools.

Abstract: A welding apparatus comprises a pair of suspension type electrode press devices for clamping an upper electrode and a lower electrode in perpendicular relation to workpieces for synchronizing them, whereby a clamping force is treated as the inner force of the pushing mechanism and the apparatus can be miniaturized. The surfaces of the workpieces can be uniformly clamped by the upper and lower electrodes whereby the consumptions of the upper and lower electrodes are substantially the same and the calibration of the positions of the upper and lower electrodes for consumption is not required.The welding apparatus is especially effective for continuous rolling in single or plural lines of a rolling apparatus for rolling hot steel billets, etc. and welding them.