DE2360885A1 - COPY DEVICE - Google Patents

Description

XEROX CORPORATION, ROCHESTER, EKY, / USA

. Copier

The invention relates to a copier with a processing unit, Transport devices for moving the copy sheets from a supply into the operating position in the processing unit, and with a melting device for fixing of the image .on the copy sheets "after the transfer of the image on the same. .

Because of possible malfunctions such as paper jams in a copier, especially one with a high

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Speed, devices are usually provided for automatically stopping the device in the event of a malfunction. For example, paper jam detectors can be provided which on the presence or absence of Copy paper at a specific location to a specific Address time. The detection of such an error resulting in a jam causes the copier to be switched off. However, there is no guarantee that the malfunction, for example a traffic jam, before restarting of the device is eliminated. This possibility can in particular

Not to be excluded in a large office where many People have access to the copier.

Furthermore, such devices usually have a melting device for permanent fixing of the copied images. Normally this includes a heater or an oven. Congestion or excessive temperatures can occur within the melting device occur, against which the melting device is to be protected. However, it is desirable that the operating work on the Melting equipment, which is often very hot, to a minimum, and for this reason it is advisable to prevent malfunctions the melting device from those of other parts.

It is an object of the invention to provide an improved copier with a controller that responds to an error in the copy fuser responds to exclude the Restart the copier until the error is eliminated.

The control should be able to differentiate between transport jams and errors in the melting device.

The copier should be designed so that it has a suitable device through which an unnecessary opening of the copier

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melting device in the event that the copier is switched off is avoided because of a malfunction.

This task is performed by a copier from the beginning. written type solved, which is characterized by a responsive to a fault in the melting device Device for switching off the processing unit, one which can be triggered by the device responding to the error Blocking device for preventing the restarting of the processing unit, and a control unit for restarting, which on the elimination of the fault in the melting device responds and releases the blocking unit and allows the processing unit to be restarted.

Further features and usefulnesses of the invention result from the description of an exemplary embodiment based on the figures. From the figures show:,

Fig. 1a, 1b a cross section through an after the electrostatic Principle working copier with the control device according to the invention;

Fig. 2 is a plan view of the copier shown in Fig. 1;

Fig. 3 is an enlarged sectional view of the automatic document input and output device .for the copier shown in Fig. 1; and

4 shows a block diagram of the control device according to the invention.

Reference is first made in particular to FIGS. 1 and 2, in which an embodiment of a copier / reproduction device 10 with an automatic program or job recovery arrange-ment of the invention is shown. As with all electrostatic systems such as the illustrated xerographic device

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-A-

becomes a photograph of the documents to be reproduced on a sensitized surface of a xerographic plate projected thereon to form an electrostatic latent image. After that, the latent image is opposed with one charged developer material to form a xerographic powder or toner image corresponding to the latent Image developed on the plate surface. The toner image is then electrostatically transferred to a carrier surface, on which it is melted with the aid of a melting device, so that the toner image adheres permanently to the carrier surface.

The original document 12 to be copied is placed on the copier 10 placed on a transparent plate 14, which is fixed to a: lighting arrangement 15 and at one end of the copier 10 is arranged. The document 12 lying on the plate is exposed, as a result of which the information areas are exposed image rays corresponding to the original are generated. These image rays are directed to the with the help of an optical system imaged photosensitive surface of a xerographic plate. In the Kcpier- / Reproduction device 10 has the xerographic plate in the form of a flexible photoelectric tape 17, which is carried by a belt system 18.

The belt system 18 for the photoelectric belt 17 has three rollers 20, 21 and 22, which have mutually parallel axes are roughly arranged in the apex of a triangle. The upper roller 22 is carried by a shaft 23, which in turn by a suitable motor or a drive, not shown, for driving the belt 17 in the manner shown in FIG is driven in the direction indicated by the arrow. During this tape movement, the reflected light image of the original writing, f. tstuck.es. 12. on "plate 14 on a light receptor surface of the tape 17 is flashed at an exposure station 25 in order to

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then to generate an electrostatic latent image.

The electrostatic image is on the belt. 17 from the exposure station 25 led by a development department 26 * in which the latent electrostatic image with the help of a toner through the twisting of a multiple — maghetiatic system

29 is being developed. From the development station 26 , the newly developed image on the belt 17 becomes the transfer station

30 moves * where the developed image onto a support surface will be transmitted ,. usually on a sheet of copy paper 31, which fed from main or auxiliary paper carriers 34 or 35 will. The copy paper sheet 31 goes to the transfer station 30 between transfer roller 32 and the 'band 17 with the im essentially the same speed as that of Bäiides 17 through, the transmission by means of an electrical Pre-tensioning takes place on transmission tube 32 in the manner known to the person skilled in the art.

After the transfer: the belt 17 is cleaned in a cleaning station 36 in preparation for the next image. There, a pas'seride brush 37 removes the remaining toner in a vacuum chamber, which through a vacuum channel 39 from the chamber 38 to a non-shown collection point is deducted. To support the cleaning, a cleaning corotrori 40 is provided upstream of the Väkuüirikämitier [__ $ 8 . "■ ---..-" ..: ■ - ' ^: "-" .- """■·'" -. """

After this. When the tape 17 is cleaned, it is loaded once more by a charging body 41 in preparation for the next image. _: .. "- -," ■ "■■" ·.

If the copier Ip is used to produce several copies ^: a number of images ¹ A'2 can be used. on; deiri Volume-17 at the same time in different processing stages of the above-described type selrii .. · '· · · ■■' - ■ "■ ^: .-

The photoelectric tape 17 comprises a photoelectric tape Layer of selenium, which is the light receiving surface and image medium for the device, on a conductive one Document. Further details relating to the structure of the tape device and the relationship to the system and its support are in U.S. Patent Application 102,312, filed December 29 19.70.

The copy sheets 31 are fed from either the main paper tray 34 or the auxiliary stacker tray 35. The main paper bin 34 has a matching height-adjustable base 44 on which a supply 45 of copy sheets 31 lies, the base 44 being carried by a means not shown for automatic up and down movement, the so is arranged so that the main paper feed roller 46 is in operative contact with the uppermost copy sheet 31 on the elevator 44 is. The feed roller 46 jerkily / aer the direction shown by the solid arrow · in cycle relationship to the Distance between the images 42 on the belt 17 is moved, is used to continue the top sheet from the feed stack 45 in the gap between tape and feed roller pair 47, 48, which in turn carry the sheet onto the main papler feed transport device 50. .

The transport device 50 has one or more endless feed belts 51, which are stretched around support rollers 52, one or both of which are suitably driven. Biatt tours 54 are in the operating position over the Tr; arisportbähde: .rn 51 are provided and are used to turn the sheets 31 into effective;] ® .; Maintain contact with the tape 51 of the tape supply transport while moving thereover. The transport device 50 carries the sheets 31 to the transfer sheet 32.

As shown in the exemplary embodiment, is.over the Main tray 34, an auxiliary tray 35 is provided which has a suitable, height-adjustable base 55 on the

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a supply of copy sheets 31 can be provided. As at the Häüp'tpapierablage 34 are not shown here either suitable means of lifting the base .55 from the auxiliary tray 35 provided when · the paper feeder is used up is to set the paper feed roller 56 for the auxiliary tray 35 in effective contact with the top sheet. The paper feed roller 56, which works in the same way as the main abi agezuführrolie 46 is operated jerkily, leads with a Put a sheet in the gap between the tape and the roller feed pair 57, 58, which in turn sends the sheets to the auxiliary paper supply transport 59 lead. The transport device 59, which one or more around the support rollers 61, one of which or several are driven in a suitable manner, -tensioned Endless belts 60 comprises, is arranged so that they of the Auxiliary tray 35 peeled sheets 31 onto the operating path of the Main tray transport device 50 dispenses. Sheets 31 of the auxiliary tray 35 are then fed to the transfer roller 32. Guides 63 serve to keep the sheets in guide contact with the auxiliary paper tray transport device 59 during to keep moving along it.

The transfer roller 32 is suitably biased to electrostatically attract and adhere the sheets 31. In this way, the sheets 31 discharged from the main supply transport device 50 are guided by the transfer roller 32 past the belt 17 and at a distance, but in an effective relation thereto, to the vacuum transport device 65. It is to be understood that the transfer of the image from the belt 17 to the coping sheet 3T then took place "when the sheet 31 passes between the transport roller and & m Barfd 17 ^.: '

After the transfer, the copy sheet 31 is means not shown stripped from the belt 17 and the image bearing sheets are conveyed by a vacuum transport device -65 carried to a melting device 69 '. -The trans-

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port device 65 has a vacuum chamber 66, the Vacuum is generated by a suitable vacuum source, not shown. The transport device 65 has an endless conveyor belt 67, which is arranged around rollers 6 8, the belt 67 having suitable perforations therethrough, through which the vacuum from the vacuum chamber 66 can suck in or hold the fed sheets 31.

The melting device 69 has a suitable housing 70 in which a lower heated melting roller 71 and an upper Pressure roller 72 are provided, which together form a nip through which the copy sheets 31 pass. The rollers 71, 72 are suitably supported for rotation and in unison by suitable drive means not shown driven. The pressure roller 72 has a relatively soft rubber-like material, with the result has that the pressure contact between the rollers 71, 72 the surface the pressure roller 72 is deformed. In this way, the contact sheet between the copy sheet and the heated fuser roll becomes 71 enlarged.

In the illustrated embodiment, the fusible roller 71 is hollow and made of a suitable thermally conductive material. A heating source such as a lamp 73 is located therein. A suitable temperature variable resistor, i.e. a thermistor

74 is in the housing of the melter 70 in heat exchange therewith for measuring the temperature within the melter 6 9 arranged. There is a suitable control circuit (not shown) to control the lamp 73 for the melter in response to the melter temperature conditions determined by the thermistor 74 intended.

The copy sheets 31 are after leaving the melting device 69 by an intermediate copy output transport device

75 to a copy output transport 76 and from there either to the

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Copy unloader transport device 78 or to the inlet of a Copy sheet handling apparatus such as a sorter 100 led. Where no sorter 100 is used or none Sheet treatment device is provided, a blocking member is used 79 in addition, all copies on an unloading transport device 78 to direct. The unloading transport device 78 carries the copies onto an output tray 80.

The copy exit transport devices 75, 76 and the copy discharge transport device 78 each have one or more endless conveyor belts 81 operatively arranged around support rollers 82, one or both of which are driven. Guides 83 are in operative relationship with each of the transport devices 75, 76, 78 and serve to maintain the copy sheets in operative contact with the cooperating conveyor belts.

Guides 54, 63, 83 are detachably supported so that their respective Transport devices emptied in the case of a papillae can be. With the guides 54, 63, 83 for the transport devices 50, 59, 75 *, 76, 78 in an effective relationship arranged sensors 84 serve to detect the loosening of the guides by the user after a jam, thereby preventing the copier 10 from restarting until the sensors 84 by opening the guides 54, 63, 83 have become active.

In the embodiment shown in FIG. 1, a sorter 100 is operatively connected to the copier 10. That Sorting device 100 is used to sort the copy sheets 31, if these are delivered by the copier TO. The sorter 100 has a matching frame 102, which is preferably on casters 103 is mounted to facilitate the movement of the sorter 100. The sorter 100 has upper and lower rows of copy bins 105, '106 on. Each row 105, 106 contains one A plurality of separate downwardly sloping trays or trays 108 for receiving and holding collated copies, with each container 108 open at the top to an inlet 109

through which the copies enter the container.

A generally horizontal copy sheet transport device 110, 111 is the container at a distance above each row 105, 106. 108 arranged opposite the inlets 109 thereof, wherein the effective length of the transport devices 110, 111 in addition sufficient that the transport devices 110, 111 can carry the copies to the most distant of the containers. The transport devices 110, 111 each have one or more endless conveyor belts 114 carried by rollers 115 of which either or both can be driven by suitable means not shown. * A number of guide rollers 117 are below arranged and are in operative contact with the lower operating path of the transport devices 110, 111, with a guide roller 117 next to the inlet 109 of each container 108 is arranged. The guide rollers 117 serve both to keep the copies in effective contact with the Conveyor belts 114 as well as a base around which the copies pass through the adjacent guide surface 120 into the inlet 109 of the container below are bent into it. A single actuatable baffle 120 is a little downstream of each roller 117 is arranged. If this guide surface 120 is placed in a raised position, then the guide surfaces act 120 with the surface <fe roller 117 together and turn a Copy from the interacting sheet transport device 110 or 111 into a container 108 below.

The sorter 100 has a copy sheet inlet 122 which is formed by a pair of sheet guides 123, the The height of the sorter entrance 122 is approximately the same as the operating height of the copy unloader transport device 76. On this The copies travel off the unloading conveyor 76 in a manner into the sorter 100 and are sorted thereby. In this mode of operation there is the blocking gate 79 of the copier 10 in the lower position.

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Adjacent to the discharge side of the inlet guide 123 is a pair of sorter feed rollers 125 provided. The pair of rollers 125, which is shown in the figure by the,, solid arrow in the figures Direction driven - is used to carry the copy in the forward direction into the sorter 100. A movable sorter inlet baffle 130 is provided directly downstream of the roller pair 120 and is used in the extended Lines shown to move the copies to the Transport device 111 and ^ the lower row of containers 106 to conduct.

So that the copy sheets 31 of the transport device 111 and the upper row of containers 105 can be fed is one Elevator transport device 132 is provided. The elevator transport device 132 has one or more end bands which are carried by a pair of rollers 134, one or both of which are driven by suitable means, not shown. A number of guide rollers 135 are located in contact with the operating path of the conveyor belt 134, the rollers 135 serving to drive the copy sheets onto the conveyor 132 to hold. The vertical transport device 132 is in one immediately downstream of the roller pair 125 operational relationship to the guide surface 130's so arranged that the guide surface 130 after setting in the figures The position shown in dashed lines directs the copy sheet 31 from the roller pair 125 onto the transport device 132.

A pair of curved paper guides. 138 is between the upper discharge end of the transport device 132 and the entrance of the upper transport device 111 arranged to operate. The pair of guides 138 serves to support the transport device 132 Turn fading leaves by about 90 on the upper hopper conveyor .111. .

During use, those leaving the copier run Copy sheets 31 into inlet 122 of sorter 100 and are

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by the pair of rollers 125 either to the lower container transport device 111 or to the elevator transport device 132 depending on the position of the guide surface 130 continued. The copy sheets directed onto transport 132 move upward and thereby to the upper tray transport 110 moves. The copy sheets 31 from the transport device 110 or 111 are put into the selected ones Containers 108 of the upper or other container rows 105, 106 are steered by selection actuation of the guide surface 120.

In the embodiment shown, an automatic document input device 150 is provided, which is best illustrated in FIG can be seen. As can be seen, the document input device is used 150 for feeding one document each time from a supply of documents 151 into the copying position on the plate 14 of the copier 10, where a copy or a series of copies is made. After copying, each document is automatically placed on document supply 151 placed, and, if available, the next document is placed on the plate 14 in the copying position. As can be seen is, the documents returned to the repository 151 can be returned through the input device or can be easily removed by the user after copying is complete.

The document input device 150 has an inclined base portion 153, the lower end of which is pivotally supported is supported by a shaft 154, conforming to left and right shelves 155. The shelves 155 are generally in cross-section U-shaped and each having a base 157, a spaced overhead top 158 and sides 159. A portion of the The base 157 of each shelf is cut off at its upper end, to mainly accommodate the document feed roller 16O. The shelves 155 are adjustable along the shaft 154 to various to be able to accommodate large documents.

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The document feed roller 160 is rotatably supported on the drive shaft 161 under the base portion 153 so that a part the periphery of the roller 160 protrudes into the document storage area with the base 153 suitably perforated is to take the roll .160. The feed roller shaft 161 is rotatably supported in a suitable manner and by suitable means not shown Means driven in the direction indicated by the solid arrow shown in Fig * 3 *

A pair of document delimitation rollers 163, 164 are located on the downstream side of the feed roller 160, the rollers 163, 164 serving to prevent the passage of more than one document at a time. The shaft 165 of the lower limiting roller 164 is indicated by the solid arrow shown in FIG. 3 Rotated direction. The upper supported by the shaft 166 limit roller 163 is arranged so that it by.die lower limit rollers 164 is driven, as long as one existing frictional force between the rollers 163, 164 exceeds a predetermined value. If the roller friction is reduced, as it occurs when two documents lying next to each other try to pass through, becomes the upper roll 163 rotated by suitable, not shown drive means in a document ejection direction, as it is by the ge. dashed arrow in Fig. 3 is shown. ·

The documents delivered by the delimitation rollers 163, 164 are fed forward by intermediate transport rollers 168, 169 below curved document guide fingers 170 to a roller transport device 171. The transport device 171, which may have a belt conveyor, transports the document onto the plate 14 of the copier 10.

A registration edge 172 is located transversely to the inlet side of the plate 14 provided, which serves to prepare the documents in a

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given position on the disk 14 for copying thereon. The plate transport device 171 is reversed for this purpose after the document is on the register edge 172 has been passed, wherein the reverse transport device 171 returns the document so far that it with its rear edge abuts the registration edge 172. After copying is finished, the disk transport device 171 again operated in reverse, so that the document is carried backwards away from the plate 14, including the Register edge 172 by suitable means not shown is withdrawn. The document guide fingers 170 direct or guide the returning document up into the Nip of a first return transport roller pair 174, which the returning document between suitable return guides 176 and into the gap of a second pair of return transport rollers 178 lead, which returns the document to the trays 155, 156.

So that the returned documents 151 'are different from those still to be supplied Documents 151 remain separate and not inadvertently by the primary feed roller 160 after being fed of the last of the original documents 151 supplied again a slidable bracket or separator bar 180 is provided substantially opposite and above the feed roller 160. The separating bar 180 is carried by a vibrating cross shaft 181. The shaft 181 is suitable in the support frame of the document input device 150, wherein the Base portion 153 thereof is suitably opened for the temple support arms 182 to be placed therethrough. There are suitable Means, not shown, are provided to selectively rotate the transverse shaft 18.1 and the bar 180 below those lying thereon To pull out documents 151 and then place them on top of the documents.

For keeping the documents returned to the document filing system and to prevent documents from being

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underJallen, especially when the bar 180 is raised, a storage lid 183 is provided. The cover 183 is carried by the shaft 154 to allow the cover 183 to be accessed the document trays 155, 156 for insertion or removal of documents can be opened.

In the following, reference is made in particular to Fig. 4-. It are leaf congestion detectors 220 at key locations along the Copy path in the copier 10 and at the entrance of the sorter intended. These detectors 220 speak in concert with the appropriate one Control circuit for a traffic jam or a blocking of the copy sheet path. To identify an error in of the melting device 69 is a detector 260 for monitoring an excess temperature in the melting device for protection against excessively high temperatures in the melting device 69 is provided. The output of the detectors 2 20 becomes the transport congestion detector circuit 207 while the output signals from the melter detector 260 are fed to the melter fault detector circuit 208 are supplied. If the circuits 207, 208 as a result of one of the detectors 220, 260 is triggered, then set the lock tüng 210 in operation and thereby terminate the copying process. At the same time, the signal from the circuits 207, 208 triggers the Print lock circuit 222, which allows restarting of the Copier 10 prevented.

The signal from a triggered transport error detector circuit 207 sets a transport interlock circuit 22G. Is the Fault in the melter 69, then caused by the trip the melter circuit 208 and the melter economy circuit 228 as. also the transport lock circuit "226 set.

The signal output of the economy circuits 226, 228 are after Triggering the same stop signals to stop the circuit ' 210 and the pressure lock circuit 222 to reset in the

prevent error-free state until the error has been eliminated. It is a transport reset circuit 230 is provided for resetting the transport lock circuit 226, which is triggered by input signals from the transport detectors 84 will. In the event of a transport jam, the copier 10 is prevented from restarting until the paper transport devices 50, 59, 75, 76 and 78 have at least been opened and closed, which is indicated by the transport detector 84 is perceived. That suggests, that upon opening and closing the various paper transport devices, the operator removes the jammed material Has.

A melter reset circuit 232 is provided for resetting the melter lockout circuit 22 8, so that the copier 10 can be restarted after a fuser failure. On the housing 70 of the Melting device, a detector 233 is provided, which by opening and closing the housing of the melting device is triggered. The resulting signal from detector 233 to reset circuit 232 triggers the circuit off, and the signal therefrom sets the melter lockout circuit 228 so that the copier 10 can be started again. ■ ".

So that there are no copies upstream of the melting device 69 can get into and become trapped in the melter due to a failure when the copier 10 is turned off is an interlock coil 235 for the melter inlet transporter-i Regulation 65 provided. The coil 235, which is in an operating position opposite the lower operating track the transport device 65 is carried, has an armature 236, which is in physical contact when the coil 235 is switched on comes with part of the transport frame 66 between the moving conveyor belts 67 to thereby move all of the copy sheets on the Stop transport device f5 at this point. Subsequent

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Copy sheets upstream of transport 65. are intercepted by the interception coil 235.

The discharge guide surface 79 has a suitable coil operator 238, which when actuated, the deflector 79 into the through the position shown in broken line in Fig. 1 rotates. In this position the copies are in the entrance of the sorter 100 steered. Suitable, not shown biasing means rotate the deflector 79 into the solid line Line shown in Fig. 1 after the spool 238 has been turned off so that the copies are directed upward onto the Exit transport device 83 for transport to the shelf

When the transport interlock circuit 226 is actuated, the actuates Signal from the same the operating circuit for the coils and 238 / to prevent upstream of the melter 69 sheets get into this, while when the spool 238 is switched off, the copies are then fed into the Paper tray 80 can be steered.

Triggers in the event of a jam in one of the paper transport directions the resulting signal from the detector 220 to the circuit 207, which in turn sets the transport blocking circuit .22.6, while the copy hold and lock circuits 210, be operated. The following signal from the transport interlock circuit 226 in turn actuates the catch coil 235 so that in the Copies in process are not in the melter. 69 while the deflection coil 238 is held off, move these copies to the tray 80 in the process. to steer. So that Copier 10 can be restarted, each of the paper transport devices must 50, 59, 75, 76 and 78 open and closed again to the associated detectors 84 to operate thereby. Accordingly, the combined signal inputs of the detectors 84 release the transport reset circuit 230 off, which in turn resets the blocking circuit 226, pas SXg-

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nal of the circuit 226, the copy inhibit circuit 222 provides back so that the copier 10 can be started again.

In the event of a fault in the melter 69, the detector 260 triggers a melter fault circuit 208 which in turn, a copy stop circuit 210 for stopping the copier 10 and a print inhibit circuit 222 for preventing the restart of the copier 10 operated. Simultaneously, the signal from circuit 208 sets both the melter disable circuit 228 and the transport lock circuit 226 in operation. As already described, the Circuit 226 in the switched-on state moves the deflection member 79 into the storage position while the blocking coil 2 35 is actuated.

To restart after actuation of the melter fault detection circuit 208, the melting device 69 must be open and the error eliminated. In the event of a paper jam the enclosed paper must be taken out. The housing 70 of the melting device is then closed again. Closing the fuser housing 70 switches the fuser reset circuit 232 for resetting the melter lockout circuit 228 and provides a control circuit of the pressure lockout circuit 22 2. Since the transport interlock circuit 226 was also triggered, the various paper transport devices must be opened and closed again to trigger the transport reset circuit 230, which in turn the transport lock circuit triggers to start the copier 10 again.

If the fault is an excess temperature in the melting device, then the detector 260 stops the copier 10. In this case, the melting device 6 9 must be opened and grounded the error can be eliminated so that the copier 10 can be started again. Where a melting device 6 9 a Pressure release mechanism of the type described in U.S. Patent Application 214,304 filed December 30, 1971, may

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the signal from the melter failure circuit 208 will also actuate the designated mechanism to stop the pressure to relax between the Schraelzeinriohtungsrolle 71,72 and to keep the melting device 69 out of operation. That Resetting of the melter 69 in this case is prevented until the error is corrected and the melter disable circuit 228 is reset. .

There can be other conditions and / or malfunctions introduce the melter fault circuit 208 can trigger and in this way both the melting device and the transport lock circuits 228 can also set. For example, opening the central unit lock or failure to release the copy sheet from photosensitive belt 17 after transfer of the image thereon can be considered a fuser jam and can serve to control the fuser failure circuit 208 to be triggered in the manner described.

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Claims (4)

Claims \.) Copier with a processing unit, transport devices for moving the copy sheets from a supply into the operating position in the processing unit, and with a melting device for fixing the image on the copy sheets after the image has been transferred to the same, characterized by one responsive to a failure in the melter (69) Means (260, 208, 210) for switching off the processing unit, a device responding to the error (260, 208, 210) triggerable bloding device (222, 228, 226) for preventing the processing unit from restarting, and a control unit for restarting (232, 233), which is responsible for eliminating the fault in the melting device (69) responds and releases the blocking unit (222, 228, 226) and allows the processing unit to be restarted. 2. Copier with a processing unit for making the copies, with a transport device for moving the Copy sheets for receiving the images thereon and with a fixing device for fixing the images on the copy sheets, the transport device at least one paper transport device has / characterized by a first detector device (207) for determining a Error in the paper transport device, a second detector device (260, 208, 210) for display an error in the fixing device (69), and a controller (222, 228, 226) for preventing a restart the processing unit to the actuation of one of the first or second detector devices up to Elimination of the error. '409824/1030 236Ö885- 21 - 3. Copier according to claim 2, characterized by a first resetting device (23Q), which on the elimination of the error in the transport device; responsive and the first detector means (207) resets _r a second restoring device, which in the fixing means (69) responsive to the removal of the fault and the second detector means (260, 2O8, 210) resets, wherein the control device is designed so that it is at Actuation of the first detector device (207), a restart of the device in response to the actuation of the first reset device (230)? enables. 4. Copier according to claim .3, characterized in that the control (222, 228, 226} by actuating the second Detector means restarting the device as Response to the actuation of the first and the second Reset device enabled. *