Abstract: Both surfaces of a substrate formed with a resist or a thin film sample can be exposed concurrently and either one surface exposure or both surface concurrent exposure of the sample can be carried out. The first groove for use in fixing the flat plate holder of transparent material held by a frame to the frame under a suction of vacuum and fixing is formed at a lower circumferential edge of the flat plate holder, the second groove for sucking by vacuum and fixing the mask film on the upper surface of the flat plate holder is formed at the upper surface of the flat plate holder and at the same time there is provided a seal member for sealing a clearance between the mask film and the end part of the sample formed with a resist position aligned to each other, and suction holes for use in sucking by vacuum and fixing the lower surface of the end part of the sealed sample are communicated with each of the seal member, mask film and the flat plate holder in a sample holding device of the exposure device.

Abstract: An appropriate photochemical reaction is produced in electrodeposited photoresist applied to the surface of a board and to the inner wall surfaces of holes extending through the board, for improving the efficiency of the operation of image formation. Upper and lower ultraviolet illumination devices and upper and lower light condensers 34a, 34b are provided. Each ultraviolet illumination device has a discharge lamp 32 and a reflecting mirror 33. Each light condenser consists of a horizontal array of a multiplicity of lenses 35 placed close to each other. The upper and lower ultraviolet illumination devices are disposed respectively above and below the board 31 in a symmetrical relation with respect to the board. The upper light condenser 34a is disposed between the upper discharge lamp 32 and the board 31, while the lower light condenser 34b is located between the lower discharge lamp 32 and the board 31. These light condenser which are spaced from each other can be moved horizontally.

Abstract: In a copying machine provided with a recirculating document feeding apparatus (RDH), the time required for the overall copying operation is reduced. In the copying machine provided with the RDH, there are cases where the copying operation is started after the number of the documents is counted. Maximum transporting speed of the document in the copying operation is a speed determined in accordance with minimum copying magnification. However, since the transporting speed of the document be set higher than the speed determined in accordance with the minimum copying magnification, the time required for the counting operation can be reduced. Thereby, the time required for the overall copying operation can be reduced.

Abstract: The invention provides a copying apparatus for producing a required number of copy sets of two-sided copy from document sheets of an original by selecting one of ADF mode in which the required number of copy sets are produced simultaneously and RDH mode in which the required number of copy sets are produced one set by one set.

Abstract: An exposure apparatus having upper and lower ultraviolet rays irradiating devices which are vertically symmetrically disposed above and below a pattern-forming board having through holes therein, and upper and lower light-transmissible plates which are disposed spacedly from each other in a light path of the ultraviolet rays irradiated to the board so as to be vertically symmetrically disposed with respect to the board and horizontally movable, each of the ultraviolet rays irradiating devices having an electric discharge lamp and a reflection mirror and each of the light-transmissible plates having an uneven surface of a sawtooth section. With this arrangement, a proper photochemical reaction can be induced to the photoresist on the surface of the board and the inner wall surfaces of the through holes to thereby improve a working efficiency of a pattern forming process.

Abstract: A method of forming a two-sided print in an image forming apparatus comprises the steps of forming images on first sides of L recording sheets, leaving M recording sheets having images printed on the first sides thereof in the transport path with a non-stacked arrangement, where M.gtoreq.2, and sequentially forming images on the first sides of N-L recording sheets and forming images on second sides of N recording sheets in a predetermined sequence dependent on values of L, M and N.

Abstract: A sheet refeeding apparatus which comprises a belt laid between a first and a second shafts, wherein as the belt is wound around the first shaft, copy sheets ejected from a copying machine are wound around the first shaft together with the belt, and as the belt is wound around the second shaft, the sheets wound around the first shaft are fed out thereof back to the copying machine. In collecting sheets, the first shaft is rotated in the same direction as that of the rotation of a photosensitive drum, and a sheet turn-over section is disposed upstream of the belt with respect to sheet conveying direction. Marks are provided for the belt to recognize the position of the belt. An initial position mark is given to the belt, and the mark functions as a standard for a return of the belt to the initial position on a supply of power for the apparatus or on the completion of a sheet refeeding operation.

Abstract: A copying apparatus includes an automatic document feeding unit for sequentially circulating and feeding documents to be copied, an image forming unit for forming images on the documents on both surfaces of each copying paper sheet by an electrophotographic process, a punching/binding unit for punching or binding a plurality of copying paper sheets subjected to image formation, an image shift unit for controlling a paper feed timing of a copying paper sheet with respect to a formation position of a document image, and a control unit for causing the image shift unit to perform image shift when even-numbered pages of documents are copied.

Abstract: A film circuit substrate exposure apparatus is disclosed, in which members movable along an optical axis such as a reticle support, a projection lens and a film pressing member are mounted on a common linear movement guide by using a linear movement driver, for instance a cross roller guide, in a predetermined spaced-apart relation to one another to set the optical axis and without inclination with respect to the optical axis. The apparatus thus pronounced practical merits such as freedom from rattling, capability of ready positioning and focusing operations, less partial out of focus or aberration of obtainable patterns, and particularly elimination of complicated operations in double side exposure.

Abstract: An apparatus for sorting and transferring sheets comprises storing means for storing a stack of sheets, first transferring means for transferring a sheet located at an end of the stack of the sheets from the storing means in a first direction, and second transferring means for transferring the next sheet located at the end of the stack of the sheets from the storing means in a second direction. The first and second directions are different from each other. The apparatus for sorting and transferring the sheets is applied; for example, to an automatic original transferring apparatus and a temporary storing tray of a copying machine.

Abstract: A copying apparatus comprising a feeding unit which can be operated in a single manual feeding mode that a sheet of copying paper set manually is fed out and in a multiple manual feeding mode that a plurality of copying paper set manually is successively fed out sheet by sheet and a refeeding unit for feeding copying paper on each sheet of which an image is formed once to an image transfer portion again. The refeeding unit is controlled, when the single manual feeding mode is selected, to perform the refeeding operation each time an image has been formed on a sheet of copying paper fed from the feeding unit, and when the multiple manual feeding mode is selected, it is controlled to perform the refeeding operation after the completion of the successive feeding and image forming operation toward all the sheets set manually.

Abstract: An optical scanning system is provided which enables a simplex to duplex copying operation without requiring the original documents to be oriented in opposite directions at the exposure station. The invention comprises a first imaging system which accomplished a scan of the first document in a first direction (e.g. left to right). At the end of the first scan of the first document, a second document is scanned in the reverse direction by a second, relay lens system which, in one embodiment, is moved into the optical path to replace the first lens. An optical reversion is thus accomplished which permits the duplex operation to be accomplished and images of the first and second documents to be formed in proper orientation on the output duplex copies.

Abstract: Herein disclosed is a recording apparatus for printing on opposite surfaces of recording medium which comprises: printing means for printing one surface of recording medium in a printing position; a looped conveyor passage for conveying again the recording medium having the printed one surface to the printing position so that another surface may be printed; and turning means disposed in the conveyor passage for turning the opposite surfaces of the once-printed recording medium upside down in a direction perpendicular to the conveying direction thereof with the tops and bottoms being in an identical arrangement.

Abstract: A duplex document handler includes a supply tray on one side of a stationary exposure position, a simplex exit tray on the opposite side of the exposure position from the supply tray and a duplex exit tray above the supply tray. A turnover drum receives sheets from the supply tray and guides them past an exposure station and to the simplex exit tray or past the exposure station and through an inverting path to a reversing location, back to the exposure station and then back through the reversing location to the duplex exit tray.

Abstract: The invention provides apparatus for coupling a pair of imaging units to receive paper along a first path from a first unit, and to invert and transfer the paper along a second path entering the second unit. Embodiments include one which in addition to inverting the paper provides an alternative path for paper so that the paper passes through one imaging unit only, and one which allows paper to pass through one or the other of the imaging units selectively.

Abstract: A method and apparatus for forming images on both surfaces of a sheet. To form such images a first column of images placed at the exposure position on an image bearing member on which images are arranged in at least two columns is recorded on one surface of the sheet, whereafter a second column of images on the image bearing member is moved to the exposure position. The second column of images placed at the exposure position is recorded on the other surface of the sheet. The image bearing member is moved in a direction parallel to the direction of arrangement of the images to dispose the next images to be recorded at the exposure position after the images have been recorded on both surfaces of the sheet.

Abstract: A frame for properly aligning to glass masters on opposite sides of a substrate is disclosed. The frame includes: (a) first alignment means comprised of spherical balls projecting from one frame member intended to mate with associated concave ball receiving surfaces associated with the other frame member; and (b) second alignment means comprised of pins capable of being inserted into bores in one frame member and pin seats in the second frame member. The frame also includes a pump and solenoid valve. Depending upon the position of the valve, the pump will either draw air from between the frame members to close the frame or push air between the frame members to open the frame.

Abstract: The duplex copying machine according to the present invention is arranged to copy both faces of an original document onto both faces of copy papers in such manner that the front and the reverse surfaces of the original document are copied correspondingly onto those of the copy papers, without inconsistency of the copied surfaces, even when paper jamming is given rise to in the course of the operation under the verso copying mode.Further, the duplex copying machine according to the present invention has such function as to positively classify the copy papers subsequent to the jammed paper into respective proper bins.

Abstract: A sheet refeeding apparatus for use in combination with a multipurpose image forming system capable of multistage copying operation. The sheet refeeding apparatus has a secondary sheet conveying mechanism forming a secondary sheet conveying path extending from the sheet discharge section to the sheet feed section of the image forming system, and includes variable speed driving means for regulating the operating speed of the secondary sheet conveying mechanism, memory means storing a plurality of control data for controlling the variable speed driving means, and selecting means for selecting control data for controlling the variable speed driving means so that the secondary sheet conveying means operates synchronously with the sheet conveying mechanism of the image forming system among those stored in the memory means.

Abstract: A printer apparatus having two-sided printing capability is taught. Two printing mechanisms are provided that can simultaneously print both sides of roll paper. The printing mechanisms are physically oriented with respect to each other and to a simple paper handling/routing mechanism comprised of rollers so that when only one printing mechanism is installed to provide only one-sided printing, the paper handling mechanism need not be modified but the roll paper is merley routed differently around the rollers. Retroactively, a second printing mechanism may simply be installed in the printer for two-sided printing and the roll paper is routed around the rollers differently to route the roll paper to and from the second printing mechanism.

Abstract: A copying machine having a function of prohibiting the operation of an automatic document take-up unit. This copying machine includes an automatic document take-up unit and a document feeder for feeding a document, a document turnover unit for turning over the document for copying of both sides of the document, a designating unit for designating a copy side, a detecting unit for detecting whether the document turnover unit is attached or not, and a prohibiting unit for prohibiting the automatic document take-up unit from operation in case the document turnover unit is not attached.

Abstract: A both side recording apparatus for recording on both sides of a sheet of paper includes printer main body provided with an image forming device and a table provided with a feed-back path. In a one side print mode, a sheet of paper is fed from a cassette and it is temporarily halted by a registration roller, and then the sheet of paper is moved past a photosensitive drum to thereby have a toner image transferred from the drum to one side of the sheet of paper. Then, after having the toner image fixed to the sheet of paper, the sheet of paper is discharged onto a tray. In a both side print mode, after image fixing, the sheet of paper is routed to the feed-back path, so that the sheet of paper is inverted and again fed toward the registration roller. In accordance with the present invention, it is so structured that a sheet of paper is transported at an increased speed while being transported at least a part of the feed-back path.

Abstract: A copying machine with a multiple transport function having a separation charger for separating from the photoreceptor surface copy paper with an image transferred thereon and a circulating transport passage formed from the paper discharge block to the paper feed block so that it is possible to select the single-sided copy mode for allowing the copy paper to be discharged outside the copying machine after the copying process, the duplex copy mode for allowing the copy paper undergoing one copying process to be led through the circulating transport passage to the copying process block as reversed, or the composite copy mode for allowing the copy paper undergoing one copying process to be led through the circulating transport passage to the copying process block without being reversed.

Abstract: Disclosed is a work alignment apparatus for double-sided exposure of a work which serves to convey to and locate the work in an exposing position such that the work is exposed on either side thereof between printing frames each holding an image mask on each corresponding side of the work. The work alignment apparatus comprises means for detecting and calculating an amount of misalignment between the work in the exposing position and each of the image masks, an alignment stage disposed outside the printing frames and adapted to determine a mounting position of the work in an alignment coordinate system in accordance with the misalignment, and means for conveying the work, in the mounting position located in the alignment coordinate system, to the exposing position.

Abstract: An electrographic printing apparatus capable of duplex printing comprises a housing, a source of copy material and an output tray for receiving such copy material after it is imprinted, and a photoconductive member for storing a latent electrostatic image of the information to be imprinted. The printer/copier has first and second paper paths located near the top of the housing so that access to the paper may be achieved from the top of the housing. A photoconductive member is located below the first paper path and comes into contact with a first side of the paper from below in a transfer zone located in the first paper path to imprint the first side of the paper. The second paper path is operative to receive paper after it has passed through the transfer zone and information has been transferred to the first side of the paper.

Abstract: A method and apparatus for exposing a pair of radiation sensitive surfaces to a beam of optical radiation is described. The apparatus comprises a support (20) for supporting the radiation sensitive surfaces which may be provided on opposite sides of an identification card. A laser (1) provides a laser beam which impinges on a pair of resonant scanners (10,11) which cause radiation impinging on their respective mirrors to be reflected onto opposite surfaces of the identification card. A control system (103) causes the mirrors of the scanners (10,11) to oscillate in quadrature. The laser beam passes through an A/O modulator (4) responsive to signals from the control system (103) to cause radiation to impinge alternately on one or the other of the scanners (10,11).

Abstract: An automatic duplex electrophotographic copying machine comprises a copying machine main body including a toner image transfer portion, a sorter having switch-back device to reverse the travel direction of a copy paper and wherein the sorter is to be mounted on the copying machine main body near a paper outlet, and a desk for mounting the copying machine main body and including a transport device communicating from the sorter to the paper feeding section of the copying machine main body. The copying machine main body, the sorter and the desk are detachable from one another. In the duplex copying mode, a single-side copied paper discharged from the paper outlet of the copying machine main body is turned over by the switch-back device in the sorter and transported by the transport device in the desk back to the toner image transfer portion.

Abstract: A copying machine capable of forming filing margins on both sides of a copying paper forms a filing margin on one side of a copying paper by an ordinary method in which an image of document to be copied is reduced and shifted, and forms a filing margin on the other side of the copying paper by means of shifting the image in a direction opposite to the direction shifted in the ordinary method by the width of the filing margin. Accordingly, filing margins are correctly formed on both sides of the copying paper in the same marginal sides, respectively.

Abstract: Disclosed is a transfer type each-side exposure apparatus which comprises light sources which oppose each other and transfer means which transfer materials to be exposed between the light sources. In one aspect, the apparatus further comprises light shielding means which prevent the passage of the light rays for irradiation as required, and control means which controls the actuation of the light shielding means. In another aspect, the apparatus further comprises reflectors which consist each of a cold mirror. In still another aspect, the apparatus is such that the light sources are each disposed in a manner that a cathode constituting its light emitting portion is displaced by a small distance from one of focal points of a corresponding reflector provided in the light source.

Abstract: A method and an apparatus for copying images printed on both sides of a document onto both sides of copy sheets uses an automatic document conveying device capable of reversing the side of a document to be copied. Also disclosed is a the resuming method of a copying operation after removing a jammed sheet during the reverse side copying step of the both-sided document and the delivering method of the both-sided document when the copying operation is cancelled.

Abstract: In an electrographic reproduction apparatus having a single process assembly for forming transferable images on a member moving along an image travel path, a mechanism for producing duplex copies on receiver sheets moving along a travel path spaced relative to such image travel path. Such mechanism includes a pair of similar doner rollers. The first doner roller is operatively associated with the transferable image-bearing member and located adjacent to one side of the sheet travel path for selectively receiving a transferable image from such member and transferring such image to one side of a receiver sheet moving along the sheet travel path. The second doner roller is operatively associated with the transferable image-bearing member and located adjacent to the opposite side of the sheet travel path for selectively receiving a transferable image from such member and transferring such image to the opposite side of such moving receiver sheet, whereby a duplex copy is produced.

Abstract: A duplex copying method of making duplex copies from one-side originals, using an electrophotographic duplex copying machine provided with an ADF and an original detection means capable of detecting the presence or absence of original document in an original input tray of the ADF, and a means for detecting whether copying is performed on a front, odd-numbered side of a transfer sheet or a back, even-numbered side of a transfer sheet, and a sheet transportation change-over means for changing the transportation so as to discharge a one-side copy sheet, with the image side down, onto a copy sheet output tray, without transporting the copy sheet to the stations for forming images on the back side thereof, when it is detected that there is no original in the original input tray of the ADF during the detection of the front side copying in a one-side original - duplex copy mode.

Abstract: An automatic duplex copying type copying apparatus for automatically copying opposite copying faces of an original document onto opposite faces of a copy paper sheet, respectively, including first and second trays for sequentially accommodating first and second copy paper sheets, respectively, an original feeding device for feeding first and second original documents from an original feeding tray to an original platform, a transport device for transporting the first and second copy paper sheets to the first and second trays, respectively, an original returning device for returning the first and second original documents to the original feeding tray and a paper feeding device for feeding the first and second copy paper sheets from the first and second trays, respectively.

Abstract: An improve image building apparatus is disclosed which makes it possible to carry out image transferrence to both the surfaces of material by bringing back material while its rear end moves ahead and displacing it to an image transferring section from first guiding means after it is displaced from first guiding means to second guiding means via the image transferring section after image transferrence is completed on the one surface of material. The first and second guiding means are extended in parallel with a discharging tray by way of which image transferred material is displaced away from the apparatus and they serve to guide reciprocable movement of the material through the image transferring section when superimposing image transferrence should be carried out.

Abstract: A method of and apparatus for exposing boards which are photosensitive on both sides, for production of printed circuits on both sides, to light through films on both sides in which a lower film, a board, and an upper film in registered position on a light-transmitting platen are pressed down by a window and exposed to light on both sides through the platen and window, the window, gripping the upper film, is raised, the exposed board is removed, another board to be exposed is applied to the lower film on the platen, the window is lowered to apply the upper film to the new board, and the procedure repeated.

Abstract: The present invention relates to a control system for a copying machine that permits the copying machine to be started by the insertion of manually fed copying paper. The copying machine can further operate with an automatic document feeder that is also operated in conjunction with the manual feeding of copying paper.

Abstract: In a method of forming images on respective upper and lower surfaces of a copy sheet in accordance with a page order of an odd number of documents, the documents are sequentially fed from the final page two at a time, and every other image is sequentially formed on the sheets. Subsequently, the documents are fed again from the final page, a noncopied sheet is fed to form the final image on one surface before the every other images are formed on the sheets each having an image on one surface. Finally, the images are formed on the other surfaces of the sheets each having the image on one surface in an order of a count-down sequence of the pages.

Abstract: This specification discloses a both-side recording apparatus in which a sheet conveyed by first recording means for recording an image on a first surface of the sheet is reversed by sheet reversing means and directed to second recording means for recording an image on a second surface of the sheet, whereby images are recorded on the first and second surfaces of the sheet.

Abstract: A printing apparatus for exposing works, such as printed circuit boards, to light uses a pallet in which a number of works and at least one associated mask are stored. The works are located in stacked relation to one another. The mask is located above the works. The printing apparatus comprises an exposure device including light sources and transparent plates, an admitting device for holding the pallet in an access position and for holding the uppermost one of the mask and works in the pallet at a certain height, a conveying device including a rail extending from the access position to a takeout position past an exposure position at which an exposure operation is performed, and an attraction device including attraction plates having a number of attraction pads mounted to the underside thereof for attracting and holding the mask and works. Each attraction plate is vertically movable while keeping a horizontal posture.

Abstract: A both-side recording apparatus in which sheets having a first image recorded on a first side thereof are temporally contained in a relay tray and subsequently a second image is recorded on a second side of the sheets has a first side recording compensation mode in which if a deficiency occurs in the number of sheets during the sheet first side recording operation, recording is continuedly effect on sheets corresponding to the number of deficient sheets, a second side recording compensation mode in which if a deficiency occurs in the number of sheets during the sheet second side recording operation, the second image is continuedly recorded on the first side of sheets corresponding to the number of deficient sheets after the recording of the second image on the second side of the sheets from the relay tray has been terminated, whereafter the first image is recorded on the second side of said sheets, and a device for changing over a transportation path so that where the image recorded on the second side of the

Abstract: A copier particularly suitable for duplex copying is disclosed which includes a paper tray unit comprising first and second paper trays having a common sheet feeder. The first tray is mounted for movement between a lowered, operative position in which it is seated within the second tray and operatively associated with the sheet feeder and a raised inoperative position in which it is spaced over the second tray and the latter is operatively associated with the sheet feeder. The unit is mounted on slides for withdrawal to facilitate access and the arrangement is such that both trays are withdrawable together when the first tray is lowered and the second tray is withdrawable alone when the first tray is raised.

Abstract: An optical system for producing substantially uniform illumination at an exposure plane has an apodized mirror in the form of a plurality of petals which can be individually adjusted to permit illumination intensity adjustment at the focal plane.

Abstract: In recirculatively precollatively copying a set of plural original documents onto both sides of copy sheets to produce a desired plural number precollated duplex copy sheet sets, by normally copying the documents only once in each copying circulation of the document set onto one side of copy sheets to form a duplexing buffer and copying other documents onto the opposite sides of the buffer copies to form duplex precollated copies, the improvement comprising: counting the number of documents in the document set and determining that the number of documents is only two or three, and in response to the determination, automatically switching the mode of copying of the documents to a higher productivity two or three document set mode in which plural identical consecutive copies are first made from only one document (the first document page) by halting the first copying circulation of the document set to copy only the one document, and forming the buffer from these plural identical copies and then skipping the copyi

Abstract: In recirculatively precollatively copying a set of plural simplex original documents onto both sides of copy sheets to produce a desired plural number precollated duplex copy sheet sets, by normally copying the documents only once in each copying circulation of the document set, and by forming a buffer set of copies of alternate document pages being duplexed which buffer set copies are printed on only one side, and temporarily stored in a duplex store and by copying alternate documents onto the opposite sides of the buffer set copies in proper sequence to form collated duplex copy sets, and wherein said documents are all copied unidirectionally in reverse (N to 1) page order, the improvement comprising: counting the number of documents in the document set and determining that the number of documents is more than three but less than approximately ten, and in response to that determination, automatically switching the mode of copying the document sheets to a higher productivity small document set mode including

Abstract: A double-side image forming apparatus has input unit for entering the number of desired image formation for forming images on both faces of a sheet-shaped image bearing member and a storage section for storing said image bearing member after image formation on a first face thereof. The apparatus is adapted, when the image formation on the first face of said image bearing members is interrupted before the completion of said desired number of image formations, to conduct in continuation the image formation on the second face of the image bearing members stored in said storage section.

Abstract: A copy sheet handling arrangement for use in a copying machine for producing duplex copies during a single pass through the processor of the machine. A transfer roller having a lead edge gripping device directs the sheet through the transfer station to receive a first toner image on one side. Reversing transport mechanism returns the sheet to the roller whereat the trailing edge is gripped and the sheet is returned to the transfer station in an inverted orientation to receive a second toner image on the other side thereof.

Abstract: An automatic document handling system particularly suitable for raster input scanners which is capable of operating in either a simplex or duplex document handling mode. The document handling system has document input and output trays in operative relation with a reversible document transport roll which in turn cooperates with a pair of displaceable pinch bars to provide both a document feeding nip and means for selectively routing the document for either duplex and simplex processing. A document guide having an integral control gate effects inverting and recirculation of the document for duplex mode or in simplex mode return of the document to the document supply tray.

Abstract: Optical system provides a uniform, well-collimated beam particularly for the exposure of photoresist on integrated circuit boards. The well-collimated beam is produced in a short beam path through the use of a series of mirrors, including concave mirrors and an integrator mirror to produce reliable exposure characteristics at the exposure focal plane. Preferably, a beam splitter is provided so that the focal plane is illuminated on both sides for concurrent exposure of both sides of the board.

Abstract: An electrophotographic copying apparatus capable of effecting dual-side copying and forming a multiple image. To automatically carry out an operation of dual-side copying, etc., apparatus for reversing a sheet (17) and for switching the path of transportation of a sheet (24,38,43,45,59) are provided. When necessary, a second switching device (25,39) for selectively delivering a sheet to an ejected sheet tray (28) is provided, or a device is provided to resupply a sheet (34,35,36) and a third switching device (32) is provided for automatically effecting delivery of a sheet to a collator.

Abstract: Method and apparatus for producing duplex copies. First and second unfixed images are transferred to opposite sides of a copy sheet before fixing of either image to the copy sheet. The first and second unfixed images may be electroscopic images sequentially formed on a photoconductor by electrophotographic techniques. The first unfixed electroscopic image is transferred from the photoconductor to a first side of a copy sheet, the sheet is inverted while the first image thereon remains unfixed, the second unfixed electroscopic image is transferred to the second side of the copy sheet, the copy sheet with the first and second unfixed images thereon is then transported to a fixing station.