Abstract: A fixing belt is applied to a fixing apparatus of an electronic photography type printer. The fixing belt consists of a belt base and an elastic layer having a thickness of 200 .mu.m or more formed on the belt base. The elastic layer consists of first, second and third elastic layers arranged in that order from the base side, and is deformable to conform to the surface shape of a recording paper so that all unfixed toner held on the recording paper can be pressed. The second elastic layer is a barrier layer for preventing releasing agent from permeating and the belt from swelling to suppress the thickening of the elastic layer as a whole and maintain the belt thickness within a range that does not cause any image noises.

Abstract: A heating device comprises an endless rotary member, a resistance heating member, a current receiver member provided at the endless rotary member and a current supply member being in contact with the current receiver member.In a form, the current supply member is made of a sintered material containing copper and carbon, and a content of the copper in the sintered material is in a range from 55% to 80% by weight.In another form, a contact surface of the current receiver member is formed of a material harder than the current supply member. The contact surface of the current receiver member and the contact surface of the current supply member have surface roughnesses satisfying a relationship of (surface roughness of the current receiver member).ltoreq.(surface roughness of the current supply member). The surface roughness Ra of the current receiver member is in a range from 0.3 .mu.m to 5.5 .mu.m. The surface roughness Ra of the current supply member is equal to or smaller than 5.5 .mu.m.

Abstract: A finisher is disclosed which is connected to a copying machine and possessed of a stapler which effects a stapling treatment on the sheets discharged from the copying machine and a binder which inserts the discharged sheets into a cover and binds by adhesion the sheets and the cover for bookbinding. This finisher has a memory for memorizing the stapling treatment or the binding treatment as a treating mode in advance, a staple sensor for detecting the existence of the staple, and a cover sensor for detecting the existence of the cover. When either of the sensors detects the lack of staple or cover, a feasible treating mode other than the unfeasible treating mode due to the lack of staple or cover in the treating mode memorized in the memory is executed prior to the unfeasible treating mode.

Abstract: A heating device comprises an endless rotary member having a peripheral surface to be moved rotatively, a resistance heating member arranged at the peripheral surface of the rotary member and generating a heat when supplied with an electric current, a current receiver member arranged in a space inside the rotary member and electrically connected to the resistance heating member, and a current supply member being in contact with the current receiver member and to be electrically connected to a power source.A heating rotary member for the heating device comprising the endless rotary member, the resistance heating member, and the current receiver member.

Abstract: A fixing device having a rotatable heating member heated by a heat source, a rotatable pressure member for pressing against the rotatable heating member, a heat-moving member formed of material having excellent thermal conductivity characteristics and constructed so as to freely make contact with at least one rotatable member among the rotatable heating member and the rotatable pressure member, and a drive unit to move the heat-moving member between a contact position and retracted position relative to at least one of the heating member and the rotatable pressure member. The heat-moving member changes either heat capacity or thermal conductivity or both heat capacity and thermal conductivity relative to the axial direction of the rotatable heating member or the rotatable pressure member.

Abstract: An induction heating fixing device is disclosed which is provided with a conducting sleeve, a coil for causing the sleeve to generate an induced current, and a high-frequency power source for feeding a high-frequency wave to the coil. This fixing device detects the switching cycle of the high-frequency power source and the electric power injected into the sleeve and, based on the detected switching cycle and the detected electric power, controls the amount of electric current to be fed from the high-frequency power source to the coil.

Abstract: In a fixing apparatus having a flexible metal fixing sleeve provided around a holder, which holds a coil inside, and heated by induction current of the coil, and a pressure roller that pinches the fixing sleeve between it and the holder by pressing on the holder, the following relation is satisfied:(F1+F2)/F3.gtoreq.1.7where symbols F1, F2 and F3 represent respectively during recording paper feeding: a drive force transmitted from the pressure roller to the fixing sleeve via recording paper in the region where the recording paper passes through; a drive force transmitted from the pressure roller directly to the fixing sleeve in the region where the recording paper does not pass through; and a friction resistance force generated between the inner surface of the fixing sleeve and the outer surface of the holder.

Abstract: A fixing apparatus for controlling an oil transfer apparatus to maintain a releasing agent holding layer such that it is not always saturated with the releasing agent. This makes it a compact, cost-effective unit with a long service life and provides a uniform, stable oil coating that eliminates image noise problems. In order to use a constant and minimum necessary amount of releasing agent, a releasing agent supply nozzle is incorporated with multiple protrusive or retrusive droplet growth assisting members at or near multiple releasing agent discharge ports. The supply nozzle used for supplying the oil has multiple discharge holes having approximately equal opening cross-sectional areas and an equalizing member which equalizes the amount of oil discharged from each discharge hole. The outer diameter D1 of the oil supply roller, the outer diameter D2 of the metal core and the distance P of adjacent through-holes formed on the periphery of the metal core satisfy a relation, 0.6<D1.multidot.(D1-D2)/(D2.

Abstract: A fixing apparatus that supports an endless belt by rollers, forms a nipping area with a pressuring roller contacting outside periphery of the belt, and fixes unfixed images on sheets that are transported into the nipping area, the fixing apparatus characterized in that transportation of the sheets into the nipping area is prohibited until the minimum belt temperature detected by a temperature sensor reaches a fixing approval temperature.

Abstract: A heating device for use in an induction heating type fixing system is composed of a sleeve 12 made of an electrical conductive material and an electromagnet 13 with a coil 20 and a core 18. It is constructed so as to fulfill the following formulas (1), (2), and (3).S1+S2.gtoreq.0.3.times.S3 (1)0.2.ltoreq.S2/(S1+S2).ltoreq.0.8 (2)1 mm.ltoreq.Dmax.ltoreq.5 mm (3)wherein S1 stands for the cross sectional area of the core 18, S2 for the cross sectional area of the coil 20, S3 for the cross sectional area of the sleeve 12, and Dmax for the maximum distance formed between the outer periphery of the holder 14 and the inner periphery of the sleeve 12.

Abstract: An image forming apparatus and a fixing device used therein capable of discriminating transport condition of a sheet in the fixing device without sheet sensors. The fixing device is provided with a fixing roller for heating unfixed toner borne on a sheet and fixing the toner onto the sheet. A temperature sensor is arranged for detecting the temperature of the fixing roller, which temperature sensor communicating with a controller of the image forming apparatus or the fixing device. The controller discriminates the transport condition of the sheet based on the temperature change of the fixing roller detected by the temperature sensor so as to execute varied control.

Abstract: A fixing apparatus which is equipped with a heat roller that has a resistance heating member generating heat by means of current supply and which is constructed such that current is supplied to the resistance heating member from the power source through a power supply member electrically connected to the resistance heating member, wherein abnormal temperature increases in the heat roller and in the power supply member can be prevented separately, as well as a control method for the fixing apparatus. The fixing apparatus detects the temperature of the heat roller and the temperature of the power supply member, and then stops the supply of current to the resistance heating member when the temperature of the heat roller is higher than a predetermined temperature for the heat roller or the temperature of the power supply member is higher than a predetermined temperature for the power supply member.

Abstract: A fixing device for heating and fixing an unfixed image to a record medium bearing the unfixed image, includes a heating roller provided with a core roller and at least two resistance heating members arranged at the core roller and controlled to be electrically powered independently of each other, the resistance heating members provide different heat distributions in a direction of a rotation axis of the heating roller.

Abstract: A finisher comprising a non-sort tray disposed at an uppermost location, a stacking tray for stapling disposed at an intermediate location, and a large-capacity storing tray disposed at a lower location. In a non-sort mode, sheets discharged from a copying machine are first stored in the non-sort tray and, when the non-sort tray is occupied full, subsequent incoming sheets are stored in the storing tray. In a stapling mode, sheets are collected on the stacking tray and, after a stapling operation, they are stored in the storing tray.

Abstract: A finishing apparatus comprising a transport section for transporting sheets discharged from a copying machine, a tray for stacking sheets thereon, and a finishing section for transporting a set of collected sheets from the tray and for stapling the sheet set. Folding rollers for folding a sheet in two or centrally folding the sheet are provided in a sheet transport section. Sheets, in a two-folded condition or with a center fold line formed thereon, are discharged onto the tray. Sheets which have been centrally formed with the fold line are subjected to stapling on or along the fold line.

Abstract: An induction heat fusing device comprises a fusing roller and an induction coil induces an induction current in the fusing roller. The fusing roller has a nonmagnetic metallic hollow roller with good heat conduction properties and a magnetic metal layer formed on the outer peripheral surface of said roller that is heated by means of an induction current induced by the induction coil.

Abstract: The induction-heating apparatus of this invention contains a conductive member, a power source, and a first and a second induction coil connected to the power source and adapted for causing the conductive member to generate an induced current, the first and the second induction coil being parallelly connected. The induction coil is formed by winding a copper wire round a core in such a manner that the numbers of turns of the copper wire gradually decrease from the lowermost layer approximating most closely to the core to the upper layers. This heating apparatus has the thickness of the induction coil in the range of 0.2-0.8 mm. The gap between the induction coil and the conductive member is in the range of 0.5-4.0 mm. This heating apparatus has the induction coil thrust out of the conductive member. The induction coil is formed of a Litz wire.

Abstract: A sheet feeding apparatus has a forwarding device for successively forwarding a plurality of sheets accommodated in a state of stacked layer one by one. The forwarding device is movable between a sheet forwarding position where the forwarding device is brought in contact with the leading end of a sheet for forwarding the sheet and a retracted position where the forwarding device is separated away from the sheet. The apparatus includes a transport device for receiving a sheet forwarded by the forwarding device and transporting the sheet in a predetermined direction of transport.

Abstract: A fixing device for heating and fixing an unfixed image to a record member bearing the unfixed image, including a heating roller, a backup member, and a current transmitting units. The heating roller includes a core roller, and a resistance heating member which is formed on the core roller and generates heat when a current is transmitted thereto through the current transmitting units, and is rotatably carried at opposite ends of the core roller by bearing units. The current transmitting units are arranged at positions opposed to the bearing units. The current transmitting unit includes a current receiver member and a current supply member. At mutual contact surfaces of them, the current receiver member has a concave section, and the current supply member has a convex section. The outer periphery circle of at least one side surface of said current receiver member has a radial difference of 6 mm or more with respect to an outer periphery circle of the heating roller at a sheet passing region.

Abstract: A copying system which has a copying machine for forming an image on a sheet, a circular transporting device for receiving a sheet which has obtained an image on one side from the copying machine and refeeding the sheet to the copying machine for image formation on the other side of the sheet, and an automatic document feeder with a document reversing mechanism. The automatic document feeder sets a document at a specified position on a document table and discharges the document from the document table. Further, in handling a double-side document which has images on both sides, the automatic document feeder turns over the document after scanning of an image of one side. When a number of copies over the capacity of the circular transporting device are to be made in a double-side document/duplex copy mode, the document is turned over every time a number of copies corresponding to the capacity of the circular transporting device has been made.