GB2141109A - Edge guide adjustment in duplex copier feed trays - Google Patents

Abstract

A control mechanism for a duplex copy tray (36) is disclosed as having side edge guides (60, 66) which are driven inwardly and outwardly to engage the sides of during duplex copying. A drive copy sheets to be collected therein mechanism (72) is provided to so drive the guides (60, 66) and a sensing arrangements (107, 109) are associated with the guides and guide members (62, 68 and 64, 70) of a sheet supply tray (30) or (28) for insuring that the duplex tray (36) is adapted to receive the size of copy sheets from the supply tray. In operation when the trays are not adjusted identically sensors (107, 109) detect this state and actuate motor M to drive mechanism 72 to adjust the guides (60, 66) of tray (66). <IMAGE>

Description

SPECIFICATION Duplex tray system for use in reproduction machines This invention relates to reproduction machines such as automatic electrostatographic copying and duplicating machines and particularly to a duplex tray system for use therein having cooperative integration with the operation of one or more copy sheet supply systems.

With the advent of high volume electrostatographic duplicating machines, the preferred use has been for reproduction runs involving duplex copying in order to save paper and cost thereof. For very large production runs, considerable space and weight is.saved relative to the handling and storage of copy sets by producing two-sided copies. Some duplicating machines include in their systems an automatic document handling apparatus, a copy sheet processor which may be provided with two or more copy sheet feed devices, and a stitching or stapling apparatus.

These machines may also include a dedicated duplex tray arranged to receive copy sheets for a transition or buffer period during which time a predetermined number of singlesided copies are produced and are transported to the tray for temporary storage. Upon completion of the production of this predetermined number, the sheets are fed from the tray back into the processor to receive a second image on the second side of the sheets. Such reproduction machines utilizing this procedure include a document handling apparatus which is not of the recirculating type, but rather provide for multiple exposures of a document sheet while the same is held upon an exposure platen and before another document sheet is placed on the platen, or before the first document sheet is inverted and brought back to the platen for similar exposure to its second side, and so on.Copy sheets produced in this manner are fed into the dedicated duplex tray and fed out again to receive second images and then transported to a sorter to be collated in copy sets in accordance with the arrangement of the document sheets being copied.

In the above-discussed manner of copying, it is imperative that the configuration of the duplex tray be compatible with that of the one or more sheet supply trays. As known in the art and in commercial copiers in the market, sheet supply trays are usually endowed with edge guides which are arranged for adjustment to accommodate various sheet sizes.

Normally, copy sheets are fed in a copy processor side edge first, that is, in the direction of their shortest dimension. For example, for the 8+ inch X 11 inch size paper, the sheets would be fed into the processor in the direction parallel to the 8+ inch diameter. In this instance, the supply tray would include guides against the sheet edges which are spaced apart the longer dimension, and these guides would be adjustably mounted to permit the affected edges to be placed therea event 2 13 inch paper gainst. In the event 8 > inch X is to be used, the operator would adjust the edge guides to be 1 3 inches apart.Some supply trays are even equipped with an adjustable back stop which will accommodate copy sheets having small variations in their short dimension, such for example, copy sheets used in some foreign countries.

Due to the recent widespread use of many machines in foreign countries, or the use of foreign sizes of copy sheets in copiers, it becomes increasingly important that the operator be aware of these many sizes and what sizes are in each of the supply trays of the copier being used. The need for this knowledge is particularly important in the event two-sided or duplex copies are to be produced. In this event, the positioning of the edge guides in the duplex tray must correspond to positioning of the corresponding edge guides of the supply tray being used.

In the prior art, U.S. Patent No. 4,153,242 discloses a two tray sheet supply arrangement which permits the loading of one tray while the other tray is in its sheet feeding mode.

The switching of one tray for another, however, must be made at the expense of idling the operation of the host copying machine for the time it takes for an elevator to move each supply tray vertically sequentially and to move each tray horizontally. There is no disclosure of side edge guides nor the need for a structure to accomplish aligned edge guides.

In U.S. Patent No. 4,008,957, an arrangement of two sheet supply trays is disclosed as having side edge guides for each tray and a control arrangement whereby in the event one of the trays runs out of paper during its use, the other tray will automatically be activated for use to permit continuation of the job for which the first tray was involved. In the event the second tray contains coy sheet which are of a size not compatible with the sheet size of the job in progress, the copying machine will be inhibited to continuing copying operation.

There is no disclosure of a duplex tray nor of any tray which has motor-driven side guides which are automatically postioned to receive copy sheets of a size being fed from a supply tray which has been adjusted for that size.

In a broader sense, U.S.Patent No.

3,820,777 discloses the use of a main sheet supply tray and an auxiliary sheet supply tray, the latter tray to be used for sheets of a size different than that in the main tray. In this arrangement, if the operator desires to use sheets of another size, rather than stopping the copying machine to change the sheets presently in the machine, the auxiliary tray may be activated to provide the other size.

Manually actuated switches are provided to permit activation of either of the two trays.

In U.S. Patent No. 3,592,464, a collection tray for receiving processed sheets has motordriven side edge guides arranged to correspond with the positioning of the side edge guides associated with a sheet supply tray. A plurality of switches are arranged along the path of movement of the guides for the supply tray one of which is actuated by the guides depending on the size of paper used, the switch then controlling the motor-driven guides in the receiving tray in accordance therewith.

Still another U.S. Patent No. 4,190,246 discloses a circuit which encodes a plurality of sheet sizes in respective supply trays, determines if any one of the sizes corresponds to the operator selected sizes, and then automatically feeds from that tray.

In the Xerox Disclosure Journal, Vol. I, Number 9/10, September/October, 1976, pages 41-42, a system is disclosed wherein the side guides of a duplex tray are automatically set when the size of paper in an input sheet tray is changed or selected thereby insuring that sheets of the size selected will be fed into and out of the duplex tray.

The present invention is directed a control and drive arrangement between a duplex tray and one or more supply trays which will automatically effect the the adjustment of the edge guide members in a duplex tray in accordance with the previously set edge guide members of either or both of the supply trays.

In accordance with the invention, a common drive is associated with the edge guide members of both of the supply trays and the duplex tray whereby the adjustment of one or both of the supply trays for a particular sized paper sheet will automatically adjust the guide members in the duplex tray in accordance therewith. The common drive mechanism serves to insure that the necessary adjustments will be accurate with no chance that relative errors between the respective guides will be able to occur. In addition, by utilizing a common drive mechanism and in accordance with the present invention, a novel control system, as will be described hereinafter, can be integrated with the drive operations to insure that automatic adjustment will take place and that it be in proper order.

Therefore it is the principal object of the present invention to condition a copier having duplex capability with a duplex tray and paper path therefor for the proper reception of copy sheets therein after the sheets have received first side images.

Another object of the present invention to insure that the size adjustments of a duplex tray is compatible with the size of copy sheets being used in a copier.

Still another object of the invention is to integrate the size adjusting devices of one or more sheet supply mechanisms with the size adjusting device of a duplex tray mechanism.

These and other objects of the present invention will become apparent upon considering the following description taken in conjunction with the accompanying drawing wherein: Figure 1 is a perspective view of a duplicating system incorporating an automatic documenting apparatus, a copy sheet processor and sorting modules to which the present invention is applied.

Figure 2 is a side elevational schematic view of the paper path for sheet feed devices in the duplicating system of Fig. 1; Figure 3 is a schematic illustration of the structural integration of the edge adjustment devices of a duplex tray mechanism and two sheet supply devices in accordance the present invention; Figures 4-6 are block diagrams of the control function utilized in the cooperative actuation of the edge adjusting devices; and Figure 7 is an electrical schematic of a control system utilized in the present invention.

For a general understanding of an automatic electrostatographic duplicating machine to which the present invention may be incorporated, reference is made to Fig. 1 wherein components of a typical electrostatographic printing machine are illustrated. The printing system is preferably of the xerographic type as one including a xerographic processor 11, a document handling apparatus 12, and a sorter arrangement 1 3. Preferably, the printing system 11, 1 2 and 1 3 is the commercial, highly sophisticated embodiment of the Xerox machine model 9500 which utilizes flash, full frame exposure, for very high speed production.Document sheet handling and exposure, image processing and copy sheet transport/handling are under control by a machine programmer and are effected in timed sequence in conjunction with the machine clock system, and in accordance with the program an operator has preset in the machine. Further details in this regard are not necessary since the Xerox 9500 Duplicator operates in this manner and is well known.

Details of the timing relationships and devices, the programmer, and related structure and events are described in U.S. Patents Nos.

3,790,270; 3,796,486; and 3,917,396, commonly assigned and which are incorporated by reference.

As in all xerographic systems, a light image of an original to be reproduced, or an electronic facsimile thereof is projected onto the sensitized surface of a xerographic photosensitive surface to form an electrostatic latent image thereon. Thereafter, the latent image is developed with toner material to form a xerographic powder image corresponding to the latent image on the photosensitive surface.

The powder image is then electrostatically transferred to a record material such as a sheet or web of paper or the like to which it may be fused by a fusing device whereby the powder image is caused to adhere permanently to the surface of the record material.

The xerographic processor 11 is arranged as a self-contained unit having all of its processing stations located in a unitary enclosure or cabinet. The processor includes an exposure station at which a document sheet to be reproduced is positioned on a glass platen 14 for projection onto a photosensitive surface in the form of a xerographic belt 1 5. The document or set of individual document sheets is selectively transported by the document feed apparatus 12 including a transport belt from the beginning of the set of sequenceed document sheets in the apparatus to the platen for exposure a predetermined number of times and then returned on completion of these exposures until the entire stack has been copied, at which time the document set handling cycle may be repeated indefinitely as described in U.S.Patent No. 3,829,082 entitled "Automatic Document Handler" and commonly assigned with the present invention.

Imaging light rays from the document which is flash illuminated by suitable lamps are projected by first mirror 20 and a projection lens 21 and another mirror 22 onto the xerographic belt 1 5 at the focal plane for the lens 21 along a path indicated by dotted lines 23.

The xerographic belt 1 5 is mounted for movement around three parallel arranged rollers 24, 25, and 26 suitably mounted in the frame of processor 11. The belt is continuously driven by a suitable motor (not shown) and at an appropriate speed. The exposure of the belt to the imaging light rays from the document discharges the photoconductive layer in the area struck by light whereby there remains on the belt an electrostatic image corresponding to the light image projected from the document. As the belt continues its movement, the electrostatic latent image passes a developing station at which there is positioned a developer apparatus 27 for developing the electrostatic latent image.After development, the powdered image is moved to an image transfer station S whereat record material or sheets of paper was previously separated from either a sheet supply stack on a main sheet feed apparatus 28 and transported by a conveyor 29 or, from a similar stack on an auxiliary sheet feed mechanism 30 and transported by a conveyor 31, to the transfer station. At the transfer station, the sheet is held against the surface of the moving belt to receive the developed powder image therefrom. The sheet is moved in synchronism with the movement of the belt during transfer of the developed image. After transfer, the sheet of paper is conveyed to a fusing station where a fuser device 32 is positioned to receive the sheet of paper for fusing the powder thereon.

After fusing, the sheet may be transported selectively to a catch tray T, the sorter 13, or finisher (not shown) or the like, or alternatively, transported back into the processor for duplexing, as will be discussed below.

The reproduction system 11, 12, 1 3 is under control of a programmer 35 which permits an operator various options: to turn the entire system ON or OFF; to program the reproduction system for a desired number of reproduction sets to be made of an original document set; to select one of many different copy reduction sizes; and to select whether simplex or duplex copies are to be made. If the duplex copying mode is selected, each sheet of copy paper bearing an image and which has passed through the fusing apparatus 32 is transported to the top of a dedicated duplex tray apparatus 36 having a bottom sheet feed device 37 by way of a transport 38. The duplex tray 36 stores one-sided copy sheets until such appropriate time as determined by the programmer 35.The apparatus 36 commences transporting the stored sheets by way of a conveyor 39 which again presents the sheets to the xerographic belt 1 5 for permitting the transfer of developed images thereon to the second side of the sheets. The duplex copies are again transported to the fusing apparatus whereat the second sided images are fixed.

Further details of the processing devices and stations in the printer system are not necessary to understand the principles of the present invention. However, a detailed description of these processing stations and components along with the other structures of the machine printer are disclosed in U.S.

Patent No. 4,054,380 which is commonly assigned with the present invention and which is incorporated by reference herein.

In accordance with the present invention, the electrostatographic duplicating machine 11, 1 2 and 1 3 exemplifying a variety of high speed duplicating systems with flexible and sophisticated features and options to automatically and conveniently process and manipulate copies or copy sets by varied selective methods or sequences, for the purpose of receiving copies in any of numerous desired quantities, formats, enhancements, and arrangements, is adapted to be converted to copying document material or the like with many convenient and automatic control features and much versatility. The resulting apparatus provides the full compliment of processing and manipulating features for copying from document sheets and document sets.

The illustrated copying/duplicating machine contemplates the use of document counters in an automatic document handling apparatus which are arranged to count the number of document sheets of a document set in the apparatus to be copied in a reproduction run.

This counting may be accomplished either by automatic precounting as the document sheets are slewed just prior to copying or concurrently as the documents are being handled during actual copying. The machine also contemplates the use of counters in the copy paper supply/feeders and along the copy paper transport path which includes the sorting modules in the duplicating system.

The control of all the exemplary sheet hand- ling systems disclosed herein may be accomplished by conventionally activating them by signals from the controller/programmer 35 in response to simple programmed commands and switch inputs from the copier console selected by the operator, such as selecting the number of copies, selecting simplex or duplex copying, selecting whether the documents are simplex or duplex, etc. These signals may conventionally actuate conventional electrical solenoid or cam controlled sheet deflector fingers and drive motors or their clutches in the selected steps or sequences as programmed.Conventional sheet path sensors or switches and bail bars, connected to the controller, may be utilized for counting and keeping track of the positions of documents and copy sheets, as is well known in the art, and taught in the above and other patents and products. Known post-collation copying systems utilize such conventional microprocessor control circuitry and connecting switches for counting the number of document sheets as they are exposed a predetermined number of times when placed upon the exposure platen 14, counting the number of completed document set circulations, and thereby controlling the operation of the document and copy sheet feeders and inverters, etc.

All references cited herein, and their references, are incorporated by reference herein for appropriate teachings of additional or aiternative details, features and/or technical background.

As shown in Fig. 2, the sheet feed apparatus 28, 30 and 36 are in approximate vertical alignment with the main feed apparatus 28 including a top feed belt device 41, the auxiliary feed apparatus including a top feed belt device 43, and the duplex apparatus 36 including the bottom feed device 37. Copy sheets being fed from the main apparatus 28 are transported by the transport 29 to the transfer station S and then by a vacuum transport 45 to the fuser 32.

After the fusing operation, the sheets are directed into one of two paths by a postfusing transport 46 and a deflector 47, one path conveying the sheets out of the processor 11 and to the sorter modules 1 3, the catch tray T or a finishing station, or the other path conveying sheets to the duplex tray 36 by way of a turn-around drum 48 working in conjunction with a belt transport 49. Copy sheets fed out of the duplex tray 36 follow the same sequence of movements as sheets fed from the main tray 28 except that the conveyor 39 and the transport 31 directs sheets from the tray 36 to a predetermined point on the transport 29 so the no machine pitches or cycles are lost when the sheets are fed from the trays alternately.

The duplex sheet return path comprises the drum 48/belt 49 conveyor, the transport 38, a pair of guide chutes 50 which directs copy sheets upwardly, a roller/belt transport 51, which finally directs the sheets into the tray 36. Sheets fed from the duplex tray are transported by a roller pair 52, a pair of guide chutes 53, the transport 39, a pair of guides 54 to the auxiliary tray transport 31, thence onto the transport 29 whereby the continued movement is the same as the sheets fed from the main feeder. As shown in Fig. 2, the distance of sheet movement from the auxiliary tray 30 to the transfer station S is greater than the distance of sheet movement from the main tray 28 to the station S. Similarly the distance of sheet movement from the duplex tray 36 to the transfer station is greater the the distance of sheet movement from the auxiliary tray to the transfer station.In order that a sheet arrives at the transfer station at precisely the same time regardless which of the trays was the source of supply for that sheet, the speeds of the transports 39, 31 and 29 are approximately the same and the timing of operation for each of the sheet feeding devices 37, 41 and 43 are arranged so that a sheet from either of the sources will arrive at the registration fingers/rollers mechanism 55. More detailed descriptions of the mechanism 55 and the registration window it provides can be found in U.S. Patent 3,804,507 incorporated herein by reference.

With this arrangement, no loss in machine pitch or cycling is lost regardless of the source of the copy sheets. The relative speeds of the transports 39, 31 and 29 may vary slightly in ascending order to prevent buckling of the sheets as they travel from one transport to another.

As previously stated, the three trays 36, 30 and 28 are generally arranged in vertical alignment relative to one another. With this arrangement, a unique control system has been devised which directly integrates the structural components of the trays for the purpose of insuring that the configuration of the duplex tray is compatible with the configuration of either source of input paper, that is, the supply trays 28 and 30. The structural/control system is shown schematically in Fig.

3 wherein each of the three trays are depicted as including left-hand sheet side edge guides 60, 62, and 64, respectively, and right-hand sheet side edge guides 66, 68, and 70, respectively. The edge guides 60, 66 for the duplex tray 36 driven by a double helical screw 72 arranged with the left-hand and right-hand segments threadedly received in internally threaded members 74, 75 to which each of the guides 60, 66 are secured, respectively. Upon rotation of the screw 72 in one direction, the guides will be driven outwardly at the same rate while rotation in the other direction will drive the guides inwardly.

The guides 60, 66 are spaced one from another a distance equal to the length of the copy sheets to be contained therein, such spacing being effected by a bi-directional asynchronous motor M. The motor M includes a pulley 76 which is connected by a timing belt 77 to a double pulley 78 secured to one end of the screw 72.

Each of the supply trays 28, 3p are provided with the conventional side edge guide adjusting devices. In the case of the main tray 28, the guides 64, 70 are each connected to a gear rack 88, 90, respectively which are operatively associated with a gear 92. Rotation of the gear 92 in either direction will drive the guides 64, 70 toward or away from each other. Similarly, the auxiliary tray guides 62, 68 are connected to gear racks 94, 96, respectively, which in turn are operatively connected to a gear 98. The gears 92 and 98 are rotated by suitable manual operated knobs (not shown) by the operator when copy sheets are placed in trays 28, 30 and the corresponding edge guides are brought against the ends of the sheets in the conventional manner.In the alternative, the auxiliary tray guides may be moves manually by the operator by means other than racks 94, 96 and gear 98.

In accordance with the present invention, as the operator actuates either of the gears 92 or 98 to effect movement of the respective edge guides as the case may be, the edge guides 60, 66 in the duplex tray 36 will likewise move correspondingly. To this end, the control system as illustrated in Fig. 3 includes a helical screw 100 having a pulley 101 secured to one end and drivingly connected to the pulley 78 by a belt 102. Energization of the motor M to impart rotation thereof in either direction will cause corresponding rotation of the screw 100 in unison with the screw 72.

An internally threaded member 104 receives the screw 100 and is mounted in a manner so that as the screw turns in either direction the member will travei axially therealong. The member 104 has secured thereto an upper flag element 105 and a lower flag element 106, both flags being movable with the member. The upper flag 105 cooperates with a U-shaped sensing element 107 secured to the right-hand edge guide 68 associated with the auxiliary tray 30. This cooperation involves the movement of the upper end of the flag 105 into and through the U-shaped element 107 to obstruct or to clear the optical path within an LED/phototransistor device 108 as the member 104 travels along the screw 100. Similarly, the flag 106 cooperates with a U-shaped sensing element 109 mounted on the right-hand edge guide 70 associated with the main tray 28.The flag 106 moves into and through the element 109 as the member 104 travels along the screw 100 during rotation thereof and serves to obstruct or to clear the optical path within an LED/phototransistor device 110 mounted within the element 109.

As will be described hereinafter, the LED/ phototransistor devices 108 and 110 are connected to the electrical energizing circuit for the motor M. When either the main tray 28 or the auxiliary tray 30 has been selected for use as the source of paper supply and the operator has actuated a tray selection switch on the machine console 35, the motor M will be energized when the optical path associated with the respective LED/phototransistor device is clear, that is, unobstructed. For example, as shown in Fig. 3, assuming the operator selected to use the auxiliary tray 30, the edge guides 62, 68 are moved by the operator inwardly or outwardly for the particuiar size of copy sheets to be used. The ensuing movement of the guide 68 displaces the sensing element 107 away from the flag 105 thereby clearing the optical path within the LED/phototransistor device 108.With the optical path so unobstructed, the motor M will become energized to effect inward or outward movement of the edge guides 60, 66 of the duplex tray 36 and corresponding movement of the member 104 by virtue of the rotation of the screw 100 produced when the motor M became energized.

This energization will continue until the flag 105 once again moves into the sensing element 107 and obstructs the optical path of the LED/phototransistor device 108. Actually in operation, since the flag 105 is insensitive as to which direction the sensing element 107 has been moved when the operator caused the guide 68 to be moved, the circuit is devised so that energization of the motor M will first rotate the screws 72, 100 in a preset direction in order to drive the guides 60, 66 and the member 104, respectively into home positions. When the member 104 reaches its home position, the direction of rotation of the motor M will reverse to drive the member 104 in the opposite direction until the flag 105 is positioned within the sensing element 107 to obstruct the optical path therein to effect deenergization of the motor M.This latter action will occur as the guides 60, 66 are spaced apart the same distance as the guides 62, 68 thereby assuring that the copy sheets to which the auxilliary tray was fitted will also be accepted by the duplex tray.

In the event the operator wishes to use the main tray as a paper supply source, a main tray select switch is actuated on the console 35 and the gear 92 is rotated in the direction to bring the guides 64, 70 against the sides of the copy sheets placed in the tray. As shown in Fig. 3, the guides 64, 70 are initially positioned further apart than the guides 60, 66 of the duplex tray 36 and the flag 106 is out of operative contact with the sensing element 109. Assuming the guides 64, 70 are in their proper position for a particular size paper, upon actuating the machine "Print" button, the motor M will become energized to drive the guides 60, 66 and the member 104 to their respective home positions.After reaching these positions, the motor will reverse in direction of rotation to drive the guides 60, 66 apart and the member to the left until the flag 106 enters the sensing element 109 and obstructs the LED/ phototransistor optical path therein. Upon this occurrence, the motor will become deenergized with the guides 60, 66 in positions compatible with the size of the paper placed in and fed from the main tray 28.

The circuit for the operation of mechanism described above and the programming therefor in block diagram form are illustrated in Figs. 7 and 4-6, respectively. The motor M, as shown in Fig. 7, includes a coil winding W-1 which when energized, will drive the side guides 60, 66 of the duplex tray 36 inwardly, and a second winding W-2 for driving these guides outwardly when energized. To energize the winding W-1, a relay R-1 is connected in the circuit thereto and includes a relay contact K-1 arranged to be closed upon energization of a coil C-i which derives its electrical power from an dc source through a limit switch 111. As shown in Fig.

3, the limit switch 111 is arranged to be actuated by the inward movement of the threaded member 75 as the edge guides 60, 66 for the duplex tray 36 reach their most inward positions. This actuation causes this switch to open thereby effecting deenergization of the coil C-i and the consequent termination of the inward movement of the edge guides 60, 66.

The electrical connection to the coil C-i is grounded through a triac 11 2 which is triggered to be conductive by the machine control system (logic) when the edge guides 64, 70 of the main tray 28, or the edge guides 62, 68 of the auxiliary tray 30, depending upon which of these trays were selected, are not in alignment with the respective edge guides 60, 66 for the duplex tray 36. As previously indicated, this condition will exist when either of the flags 105 or 106, associated with the chosen supply tray, is not in position to intercept the optical path of its sensing element 108 or 109.

After the limit switch 111 has been actuated to its open condition by the movement of the side edge guide 66 to its most inward position, about four seconds of time are allowed to elapse by a suitable timer in the machine logic before a signal from logic energizes an LED 114 for rendering a phototransistor 11 5 conductive. The LED 114/phototransistor 11 5 device serves as an optical relay in the illustrated circuit. Conduction of this phototransistor completes the circuit to a triac K-2 from a dc source to ground by way of either electrical path to be described below.

In this manner, the triac K-2 becomes energized thereby energizing the winding W-2 of the motor M. With the winding W-2 energized, the motor M will drive the edge guides 60, 66 outwardly starting from their inward most or home positions.

For energizing the triac K-2 for driving the guides 60, 66 outwardly, the electrical path to ground depends on which of the supply trays were selected for use. If the main tray 28 was selected, a switch on the control panel 35 would have been actuated for enabling the machine logic to render a transistor 11 6 conductive. This transistor is connected to a phototransistor 11 7 associated with the sensing element 109 on the righthand guide 70 of the main tray 28. As previously stated, when the flag 106 is not in position to intercept the optical path within the element 109 the LED/phototransistor device 110 is conductive.For simplicity, the phototransistor in the device 110 may be considered the component 11 7. As the guides 60, 66 are being driven outwardly, the threaded member 104 is being driven therewith until the flag 106 enters the sensing element 109 and intercepts the LED/phototransistor optical path therein whereupon, the transistor 11 7 becomes non-conductive and thereby opening the electrical path for the triac K-2. This condition of the transistor 11 7 will cause deenergization of the winding W-2 with the consequent termination of the driving action of the mdtor M. The sideguides 60, 66 of the duplex tray 36 are now in coincidence with the corresponding side guides 64, 70 of the main tray 28. Copy sheets in the main tray may now be fed into and out of the duplex tray. To insure that this condition exists, a circuit including a pullup resistor 1 20 and a diode 1 21 is connected in the circuit which includes the elements 116, 11 7 and is connected to the machine control to inform the same by way of a side guide coincidence signal that the duplex tray is compatible with the selected tray so as to permit continued operation of the machine. Until the machine receives this signal, its operation in a reproduction run is inhibited.

In the event the auxiliary tray was selected as the source of paper, the actuation of an auxiliary tray select switch on the machine control panel, as depicted by the transistor 122 in Fig. 7, will render the same conduc tive. Assuming that the flag 105 is not within the sensing element 107 to intercept the optical path of the LED/phototransistor 108 therein, a condition indicative of the noncoincidence nature of the duplex tray edge guides relative to the corresponding auxiliary tray edge guides, the transistor 1 24 of the LED/phototransistor device 108 will be conductive thereby completing the energizing circuit to the triac K-2 as was the case for the selection of the main tray.When the flag 105 enters the sensing element 107 to cause interception of the optical path therein, the transistor 1 24 becomes non-conductive and the circuit to the triac K-2 is opened to terminate operation of the motor M. As in the case with the main tray, a pullup resistor 1 25 and a diode 1 26 are connected in the tray select circuit to inform the machine control that the selected tray has its edge guides compatible with the edge guides of the duplex tray. Continued operation of the machine may now be provided now that this interlock condition has been eliminated.

From the foregoing, it will be appreciated that the present invention insures that the duplex tray in a copier having one or more supply sources will always be compatible to the particular source in regard to sheet size and that in the event the copier is endowed with automatic tray selection, the supply tray which is automatially activated as a supply source after the originally operated tray experiences a low or no paper condition, the second supply tray must be compatible with the duplex tray as to sheet size or the copier will be inhibited from the continued operation.

While the invention has been described with reference to the structure disclosed, it is not confined to the details set forth, but is intended to cover such modifications or changes as may come within the scope of the following claims.

Claims (5)

1. A reproduction machine capable of duplex copying and including a sheet supply tray and a duplex tray arranged for collecting copy sheets having an image on one side copied thereon, and means adjacent the duplex tray for feeding the copy sheets out of the duplex tray to receive a second image on the other side, said machine including at least one edge guide member associated with the duplex tray being arranged for movement toward a position adjacent a side edge of copy sheets to be collected therein, at least one edge guide member associated with the sheet supply tray being arranged for movement toward a side edge of copy sheets therein by an operator in accordance with the size of the copy sheets, drive means operatively associated with said edge guide of the duplex tray for moving the same in a direction toward said position, and sensing means associated with said edge guide of the supply tray and said drive means for actuating the latter when the said edge guides are not positioned to receive the same sized copy sheets.

2. A reproduction machine according to claim 1, in which said sensing means has an element movable by said drive means as the same moves said edge guide of the duplex tray for effecting actuation of the latter when the said edge guides are not positioned to receive the same sized copy sheets.

3. A reproduction machine according to claim 1 in which said sensing means includes a first sensing member associated with said edge guide of the supply tray and a second sensing member adapted for coincidence with said first member and being movable by the drive means as the same moves said edge guide of the duplex tray, said sensing means further including a circuit connected to said drive means and associated with said sensing members whereby said drive means is actuated to move said edge guide of the duplex tray in said direction when said sensing members are not in coincidence.

4. A reproduction machine according to claim 1, in which said drive means is adapted to move said edge guide of said duplex tray in response to a control signal, and sensing means includes first and second operative elements movable relative to each other and when not in coincidence being adapted to produce said control signal, said first element being operatively connected with said edge guide of the suply tray to be movable therewith, said second element being operatively connected to said drive means, said drive means being actuable upon said edge guide of the duplex tray to move the same to said position when said elements are not in coincidence as indicative that the edge guides are not positioned to receive the same sized sheets.

5. A copying machine capable of duplex copying and including a sheet supply tray and a duplex tray arranged for collecting copy sheets having an image on one side copied thereon, and means adjacent the duplex tray for feeding the copy sheets out of the duplex tray to receive a second image on the other side, said machine including at least one edge guide member associated with the duplex tray being arranged for movement toward a position adjacent a side edge of copy sheets to be collected therein, at least one edge guide member associated with the sheet supply tray being arranged for movement toward a side edge of copy sheets therein by an operator in accordance with the size of the copy sheets, sensing means associated with said edge guide of the supply tray and arranged for producing a signal when the said edge guides are not positioned to receive the same sized copy sheets, drive means operatively associated with said edge guide of the duplex tray for moving the same in a direction toward said position in response to said signal, and, actuating means movable in unison with said edge guide of the duplex tray toward said position operable to inhibit the production of said signal as being indicative that said edge guides are positioned to receive the same sized copy sheets.