DE2062278A1 - Conveyor device for transporting sheet material - Google Patents

Description

Dipl .. - ING. E ¥ eIGKMANN,

Bifl.-Ing. H-Weickmann, Dipt.-pHYs. Dä, K. Fincke . RA Weickmann, DrPLZ-CHEM. B. Huber

xpr ■■■ · -. ■■

8 MUNICH 86, DEN

XEROX CORPOMiIOKT, P.O.Box 860820

Xerox Square »möhlstrasse 22, phone number 483921/22

Rochester, H, Y.14603 / USA

Conveyor device for transporting sheet material

The invention "relates to a conveyor device for transport of leaves one after the other on a rotating cylinder, the one with a gripping device for the respective leading edge of the sheet is equipped. In particular, the invention is suitable for the transport of documents that a Copy drum to be supplied on which they are detachable held and released again as required will.

In printing technology and in reproduction technology there there are various devices with which thin, flexible sheets, such as documents or sheets of paper, with a cylinder or a copy drum be moved in a circular path. These well-known Arrangements are equipped with gripping devices, with which one. Sheet releasable on the drum or cylinder can be held and released again as desired will. ■■ -. '.

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Known arrangements of the type described above must be brought into an input position in which the respective Document is normally fed to the gripping devices by hand. As a copy drum, however Usually inside the machine inaccessible to the operator, it is difficult to make a decision to decide when the document is to be released for input on the copier drum. If this is done too early so it may not be taken in correct alignment on the copy drum, while if it is too long it will Keeping the copier drum ready can be repelled and possibly damaged.

The object of the invention is for conveyor devices the known type to improve the feeding of the document to a rotating copier drum so that the Copy drum takes over the document in the right place without having to be stopped.

A conveyor of the type mentioned is for This object is achieved according to the invention in such a way that that a sheet lock is provided on a guide device forming a predetermined transport path, which is unlockable by a first cam mechanism, and that one operable by a second cam mechanism Roller drive is arranged in the area of the locked position of a sheet, which the respective sheet when it is released feeds the gripping device.

The invention is illustrated below with reference to one of the figures illustrated embodiment described. Show it:

1 shows a schematic representation of an embodiment a device according to the invention within an electrophotographic reproduction machine,

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Fig. 2 is an enlarged view of part of the invention The device and FIG. 3 is a partial view of the arrangement shown in FIG.

In Fig. 1 is an electrophotographic reproduction machine shown, with which electrophotographic reproductions of a moving original image can be produced, wherein a conveyor device for moving the original image 10 is provided. The reproduction machine is located in a light-tight housing, which is the arrangement of the entire facility, for example, on an office table. The reproduction machine includes an electrophotographic Recording disk with a photoconductive layer or a photosensitive surface on conductive Support in the form of a drum 20, which is in the machine frame is rotatably mounted in the direction of the arrow shown and its surface successively on a number electrophotographic process stations moved past.

The various electrophotographic process stations are briefly described below with regard to their function?

At a charging station, a uniform electrostatic Charge on the photoconductive layer of the electrophotographic Drum applied. . At an exposure station, a light or radiation image of an image to be reproduced is placed on the drum surface projected in order to dissipate their charge in the irradiated surface parts and thus a latent electrostatic Generate image of the image to be reproduced. At a development station, an electrophotographic Developer, the toner particles with an electrostatic Contains charge opposite to that of the electrostatic latent image across the drum surface

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cascaded, whereby the toner particles adhere to the electrostatic latent image and an electrophotographic Generate a toner image with a distribution corresponding to the image to be reproduced.

At an image transfer station, the electrophotographic Electrostatically transfer toner image from the drum surface to a copy sheet and

At a drum cleaning and unloading station, the drum surface is first loaded and then brushed to remove to remove any remaining toner particles, then it is illuminated with a relatively bright light source, in order to achieve a practically complete dissipation of any residual electrostatic charges.

At the charging station A shown in Fig. 1, a corona discharge device 21 is arranged with a or several discharge electrodes are provided which run across the drum surface and with a High voltage source are fed. They are arranged within a shield.

This is followed by the exposure station B in the area of movement of the drum surface. One of the known devices can be used here be provided for optical scanning or projection, etc., with which the image to be reproduced, if necessary is projected line by line onto the surface of the photoconductive electrophotographic drum.

The optical scanning or projection device contains an original carrier in the form of a drum, which is described below is referred to as copier drum 22. This drum carries an original image that you received with the conveyor 10 is fed. It moves the original image to project it in accordance with the movement of the light-sensitive Electrophotographic drum surface.

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Uniform lighting is provided with lamps that are in a slotted reflector 23 are arranged near the copying drum.

A light shield 24 protects the electrophotographic Drum against external light and is near its surface arranged. A slot opening in the shield runs across the direction of movement of the photosensitive drum surface 20 and allows the light rays reflected by the copying drum to pass through to a limited, area of the drum surface running transversely to the movement. ■■■■. "

To the optical system in a relatively small housing to be able to arrange, are an object cleaning gel 26, an optic * 27 and an image mirror 28 is provided which has a folded generate optical axis.

A fed with the conveying device 10 of the copying drum Original image is held on the drum with a gripper mechanism 32 so that it is timed upon movement of the electrophotographic drum, thereby creating a continuous light image of the original image is projected onto the electrophotographic drum. The original image appears on the surface of the copy drum held with guides that also prevent the trailing edge touches a belt cleaner 54 of the respective sheet. After the original image is scanned, it can be removed from the Copy drum can be released and discharged from the machine with an output conveyor 34 which carries it off the surface the copying drum is transported away by a guide 30 *

Near the Beiichturigsstattori is; the development station G provided in which a lintwlctelimgsvorrlchttmg 35 with a

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BATH ORIGINAL

Development housing is arranged, in the lower region of which a supply of developer material 36 is accumulated. A motorized bucket conveyor is arranged within the development housing, which feeds the previously into the development housing entered developer into the upper area of the development housing, from where from it is cascaded via a funnel-shaped chute onto the electrophotographic drum.

As the developer falls over the drum, its toner particles electrostatically adhere to the previously formed electrostatic latent image and create a visible electrophotographic toner image. The remaining developer falls back into the lower part of the development housing in front of the drum surface. The toner particles used up during development can be replaced with a toner input device 37.

The image transfer station follows the development station D, on which a sheet conveying mechanism is provided, with the sheets of paper successively the electrophotographic Drum is fed in accordance with the appearance of a developed image at the image transfer point will. The sheet feeding mechanism comprises a sheet tray 41, in which a sheet supply is provided. These paper sheets or the like are removed from the stack of sheets with a separation roller 42 fed to the conveyor 43, which is provided with grippers 44, which the respective copy sheet to the rotating electrophotographic Move the drum forward when a developed image on it arrives at the image transfer station.

The electrophotographic toner image is transferred from the drum surface to a copy sheet with a Corona transmission device 45, which is near or immediately located at the interface between the copy sheet and the electrophotographic drum, Dir;

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BATH ORIGINAL

Corona transfer device 45 is similar to the corona discharge device formed, which is arranged at the charging station A. It also contains one or more Corona discharge electrodes connected to a high voltage source are fed and run across the drum surface. They are arranged in a shield. At the In operation of the assembly, the electrostatic field generated by the transfer device causes adhesion of the copy sheet on the drum surface and at the same time thus attracting the toner particles of the electrophotographic toner image from the drum surface so that they electrostatically adhere to the surface of the copy sheet.

While the gripper mechanism 44 on a self-contained Moved away, it peeled off the copy sheet from the electrophotographic drum and conveyed it to one Fixing device, for example to a melting device 46, with which the developed and transferred electrophotographic The toner image is permanently fused onto the copy sheet.

After fixing, the finished copy is preferably output from the machine at a suitable location and outside the machine collected with other copies. For this purpose, two output rollers 47 and 48 are provided with which the Copy to one after approval by the gripper mechanism Sämmelfach is fed. At the pick-up and drop-off points cam devices are provided on the sheet feeder, which actuate the gripper at these points in order to take over or deliver a copy sheet.

The last process station is the cleaning station E, at which anything that is still present after the image transfer Toner powder removed from the electrophotographic drum surface and the drum surface with a light source is lit to provide an electrostatic discharge

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To effect residual charges.

In order to promote the removal of the remaining toner powder, a corona pre-cleaning device 51 is provided which is designed similar to the corona discharge device at the charging station A. The removal of the remaining toner powder from the drum surface is carried out with a belt cleaner 54, which continuously removes a clean, fibrous belt in Brings wiping contact with the electrophotographic drum. The strip material 55 is fed from a supply roll 56, around a cleaning roller 57, which is preferably made of rubber, and around a guide plate 58 and wound on a take-up reel 61.

Any remaining electrostatic charges are removed from the drum surface with a fluorescent lamp 62, which is placed in a suitable holder above the electrophotographic drum. A starting device is provided for switching on the lamp.

The electrophotographic drum, the copying drum and the sheet feeder are provided with a drive device Driven predetermined relative speeds, which also controls the operation of the paper separation roller and the cleaning mechanism. The cleaning mechanism is with moves at a speed that creates relative motion between the drum surface and the cleaning belt. Further, drive devices for the conveyor and the toner input device of the developing device intended.

The preceding description may be useful in understanding the general operation of the described electrophotographic Reproduction machine sufficient. Further details of such machines can be found, for example, in

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U.S. Patent 3,099,943.

In Figs. 2 and 3, the conveyor device according to the invention is 10 shown, with each of which a document is fed to the copying drum 22 in a predetermined sequence. The conveyor device 10 includes an input guide 70, which consists of two guide surfaces 71 and 73, which are arranged at an angle to each other and a document feeds down the conveyor rollers 81, which with constant speed by a (not shown) Drive mechanism are rotated. The conveyor rollers 81 are tilted against each other in such a way that an entered document is moved to one side at the same time as it moves forward, so that it is laterally aligned with the guide will. Pressure rollers act on the conveyor rollers until the document touches a sheet stop 85.

There is a switch in the movement area of the document arranged, which is connected to the program control of the reproduction machine, so that when moving past a The corresponding operating state of the machine control is signaled to indicate that a Document is ready for promotion on the copier drum. When the switch 86 is actuated and the machine controller instructs a document to be fed to the Copy drum has reached the appropriate state, is a signal is supplied to an electromagnet 88 so that it has a flap mechanism for a purpose to be described 89 actuated.

There are two cam elements 90 and 91 on the drum axis arranged, which are moved with the copying drum. They are adjustable in order to achieve a predetermined interaction with one another during the rotation of the drum. A Cam follower 93 follows the movement of the cam member

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and is clockwise (Fig. 2) on a pivot axis 94 rotated by a spring 95 when the flap mechanism -89 is operated. The cam follower 93 is with a Drive pin 96 is provided, which acts on a fork element 102, which in turn has an axis 104 in the counterclockwise direction turns. The axle 104 carries two arms 106 which carry an axle 108 and a pin 109. When the axis 104 is rotated counterclockwise, a pressure roller 114 is moved down against the action of a spring 110 and holds the respective document on a lower roller 121. Furthermore, the arms 106 with the pin 109 raise it the blade lock 85.

The document can now be conveyed onto the copier drum. At this time, the cam member 91 is in Timing rotated with the drum and moves a driver 126, which is provided with a toothed sector 120 which meshes with a gear 129. This sits on an axis 130 and rotates the lower conveyor roller 121, whereby the document is brought onto the copier drum. The cam member 91 is formed so that it Document accelerates smoothly and generates movement at a speed slightly greater than that the copy drum is. As a result, the document is slightly hunched up against the gripper mechanism 32. When the document reaches the copy drum surface, the gripper mechanism closes and holds the leading edge of the sheet firmly. Once the document is gripped in this way, the pressure roller 114 is through the Effect of the axis 108 raised and the conveyor roller 121 braked. Further, the blade lock 85 is lowered. to At this point, the conveyor is ready to convey another document, which is in the chute is entered automatically or manually with a suitable mechanism. A control is used to open the Gripper mechanism to pick up the document, as already

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wrote to release from the copy drum.

A conveyor device has been described above, ' with the documents of a copying drum at a predetermined time without stopping the copying drum can be fed. There is also a mechanism for writing documents or other Automatically brings sheet material to an input point and automatically feeds the respective sheet to the copier drum at the correct point in time. A conveyor according to the invention is therefore particularly advantageously suitable for use in copying machines of the above described type.

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Claims (5)

IjJi-J - - 12 - Claims [1 j Conveyor device for the transport of sheets one after the other onto a rotating cylinder, which is equipped with a gripping device for the respective leading edge of the sheet is, characterized in that on a guide device forming a predetermined transport path (70) a blade lock (85) is provided which can be unlocked by a first cam mechanism (90, 93), and that a by a second cam mechanism (91, 126) actuatable roller drive (121) in the area of the locked Position of a sheet is arranged, which feeds the respective sheet when it is released to the gripping device (32). 2. Conveyor device according to claim 1, characterized in that the guide device (70) conveyor rollers (81, 84) are assigned, which the respective sheet from the guide device (70) in the direction of the gripping device (32) transport. 3. Conveyor device according to claim 1 or 2, characterized in that that the roller drive (121) through the second cam mechanism (91, 126) faster than the surface of the cylinder is moved. 4. Conveying device according to one of the preceding claims, characterized in that in the range of motion of the respective sheet in front of the sheet lock (85) a switch (86) is arranged, which the provision of a respective sheet for transport to the cylinder (22) is signaled. 5. Conveying device according to claim 4, characterized in that an electromagnet (88) is provided which when switched on, remove the flap mechanism (89) from 109826/1 1 63 .- '13 - travel range of the second cam mechanism (91 »126) moved out. 109826/1 163