DE2449684A1 - PAPER CUTTER FOR COPY MACHINES - Google Patents

Description

The invention relates to a paper cutting device, in particular for use in a copier.

There is a need for a compact size and simplification of an electrophotographic copier having a reciprocating platen for placing an original to be copied. However, in such a known copying machine in which a roll of copying paper is used, a paper cutting device is controlled by an adjusting knob for adjusting a paper size, which is attached to the machine body in order to reduce the length of the paper.

509818/0845

to discontinue sons' paper. This is well known Paper cutting device independent of the other devices of the copier built in, whereby a more complicated construction of the copier is obtained without the to meet the requirement described above.

In addition, the length adjustment knob of the above-described known paper cutting device tends to only to be cumbersome to operate, so that a long time is required for very precise adjustments and also different Cut lengths occur, which in turn adversely affects routine copying operations, where most of the copies desired are of regular sizes, such as A4 and B5 sizes, and hence the cut lengths are most common on these regular ones Sizes set as the unification of copy sizes to standard sizes for efficient arrangement of the documents is desirable. In other words, individual changes result in the setting of the Adjustment knob in the well-known paper cutting device, even if a desired cutting length is set, there is a certain amount of deviation in the cutting lengths.

In addition, in some known paper cutting devices, the location of a microswitch or a rotatable Partly moved to operate the microswitch by an adjustment button on the housing of the copier

- 2 5098 18/0845

for changing the angle of rotation of the microswitch or the rotatable part is attached to the cutting length of the printing paper that is unwound from the paper roll. However, this known paper cutting device has in particular, the disadvantages that successive copying operations can not be done until the rotating part for operating the microswitch in the original The starting position for copying has returned after it has carried out exactly one revolution from the start of shooting, which results in a slow copying speed, so that a complicated mechanism is required to copy the rotatable part quickly returned to the original starting position for copying, after the part hit the microswitch has operated in order to overcome the disadvantages described above.

Therefore, it is an essential objective of the present invention for printing paper that is unwound from a paper roll, to provide a paper cutter, which has a simple construction ^ and a compact size and can be produced at low costs, with the well-known paper cutters own Disadvantages are essentially avoided.

Another important object of the present invention is to provide a paper cutting device of the type described above having a length adjustment knob which

- 3 B09818 / 0845

2449884

can be adjusted correctly and quickly without changes in the cutting length.

Another object of the present invention is to provide a paper cutting device of the type described above to create that associated with the mechanism of the copier without adversely affecting the copying speed will.

According to a preferred embodiment of the paper cutting device according to the invention, the fact is taken into account that a copier with a reciprocating support surface generally has a locking device for fixing the support surface at a predetermined location, a device for releasing the support surface when it is pushed towards the gate and a transport device, for example rollers, In particular, the paper cutting device according to the invention has a price release mechanism for the contact surface lock, which can be actuated by a signal from a microswitch actuated by the drive device on the contact surface, which is operated along the transport

ι is arranged away from the paper web of a paper roller, the microswitch when the paper web passes through the paper feed rollers are actuated »Also draws the Fapierschneiäevorrichtuiig according to the invention a locking member for a cam plate »which actuates and is released in connection with the price release device the locking device for the support surface, by a

509 8 fs / 08 * 4 5

Cam plate that rotates one revolution in conjunction with a feed roller makes for the printing paper at the same time as releasing the plague actuator for the Noekenplatte, by one Adjustment lever for the cutting length, which makes one turn with the cam plate after moving gradually in a desired one Position on the cam plate according to the length of the original by one with an adjustment knob for the The locking device associated with the cutting length is set by means of a string idesignal micro switch that is operated by the setting lever can be operated for the cutting length, and through

3.LiS

a cutting device which can be actuated by a signal from the cutting signal microswitch. As the prelivering device for the closing device of the support surface and the transport device for the paper in more advantageous Can be used for the start-up and for the drive of the cutting device, iat the construction the paper cutting device of the present invention is remarkably simple, resulting in low cost and reduction the size of the copier.

The inventive use of the locking device,

#
which is connected to the adjusting lever and the adjusting knob for the cutting length, is extremely effective for the final and quick setting of the cutting lengths without individual changes occurring in the cutting lengths of the printing paper.

The features of the invention are hereinafter Toggle 60 9 8 1 "* / 8 * 6%

-ς «

hand exemplary embodiments with reference to the attached Drawing explained in more detail. Show it:

Fig. 1 is a schematic side view in cross section of an electrophotographic copier the paper cutting device according to the invention,

Pig. 2 shows, on an enlarged scale, a perspective view of a control plate for the inventive Paper cutter,

3 shows a side view of an embodiment according to the invention the paper cutting device in a schematic representation,

Pig. FIG. 4 is a plan view, partly in cross section and partly broken away, of an adjusting knob of FIG Cutting length for the paper cutting device, in particular its construction, according to Pig. 3,

Pig. 5 shows a schematic representation in side view of a modification of the embodiment according to FIG Pig. 3 and

Pig. 6 is a plan view, partly in cross-section and partly broken away, of an adjustment knob for the Cutting length of a paper cutter

509818/0845

measured Pig. 5, particularly showing the contraction of the paper cutting device.

In the following, the same parts with the same reference numbers are used in the various "figures".

In the pig. 1 and 2 will illustrate an electrophotographic copier of the slot exposure type for general understanding shown, which has a movable support surface * can be placed on the original to be copied, the copier using the paper cutting device according to the invention having.

In Pig. 1, a web of printing paper R ¹ is unwound from a paper roll R, which is rotatably attached to the upper left part of the copier, by a pair of rollers rl ¹ , r1 and by roller pairs r2 ^! , r2, r3 ', r3, r4 ^for r4, r5', r5, r6 ^J , r6 and r7'j r? which are sequentially arranged along a path Ra for the printing paper R ¹ . The feed rollers r1 ^f , r1, which are arranged in the vicinity of the paper roll R, are to operate when a copy-triggering switch PS (Pig. 2) attached to a control panel W located on the front of the copier is depressed is, the feed rollers rl ¹ , r1 interrupt the feeding of the paper R ¹ at the moment when a cutter C, which is arranged between the roller pairs r1 ·, r1 and r2% r2 is operated by a later-explained cutting signal

- 7 -609818/0846

will. A microswitch SW1 _t, which is arranged along the paper path Ra between the rollers r3 '> r3 and a pair of opposing corona chargers CH, is provided to release the closure of the support surface 29 in the horizontal direction, which is movable to and fro on the upper part of the copier is held so that it is movable in the scanning direction shown by an arrow a with the original P to be copied. In addition, the micro-switch SW1 energizes the corona chargers GH, a light source Ii disposed below and in the vicinity of the support surface 29 for illuminating the original P, and a clutch, not shown, for reciprocating the support surface 29. An optical system M arranged between the support surface 29 and the paper web Ra has a mirror m1, which is fixed below the support surface 29 and at an angle of approximately 45 ° with respect to the support surface 29, in order to transfer the imaging rays from the original P to a mirror m3 to be directed through a mirror lens m2, this mirror m3 in turn directing the imaging rays onto an exposure device E, such as a pair of transparent guide plates g1 and g2, which between the walnut pairs r4 '»£ 4 and r5 ^! , r5 are arranged so that the angle of the original P is formed on the printing paper R ¹ which is moved along the path Ra in synchronism with the scanning movement of the platen 29. The so exposed® printing paper R ¹ is then developed in a developing device B, which has a

303S18 / 0S4E

Has winding container t and an electrode plate e, and then in a fixing device F with a heater h and a fan f, to be then dispensed on a dispensing tray d.

In Fig. 2, a control panel W is shown, which is on the Front side of the copier is arranged. A main switch MS and an indicator lamp PL are on the control panel ¥ Adjustment knob k1 for the cutting length in conjunction with an indicator disc i for the cutting length, on the circumference of which the Copy sizes, for example B4 »A4 and B5 etc., are marked to increase the cut size through the opening 01 recognize an exposure setting button k2 with a corresponding scale, a setting button k3 for continuous copying with corresponding display disc 11 for displaying the number of copies through an opening 02 and the copy pressure switch PS arranged. The setting knob k1 in Fig. 2 is set so that the paper web R 'from the roll R in A5 size is cut off.

3 and 4, the setting knob k1, the hub i ^{1 of} the indicator disk i and the hub 3, which is integrally connected to an adjusting lever 2 for the cutting length, are fixedly attached to a shaft 1 by locking screws 4 5 and 6 , which is rotatably supported by the frame 24 of the device and the wall of the control panel W, so that the setting lever 2 for the cutting length in connection with

- 9 S09818 / 0846

the adjustment knob k1 for the cutting length can be moved.

The movement of the lever 2 is gradually controlled by a locking device such as a locking spring 7, snap-in balls 8a and 8b, which are arranged by a between the snap-in spring 7 and a cam plate 10 Embossing plate 9, which can be moved together with the lever 2, the ball 8a being closer to the shaft 1 as the ball 8b to stabilize the locking spring 7 and has corresponding recesses 11 for the balls 8a and 8b, formed on the surface of the cam plate Ί0. The hub 3 is attached to the shaft 1 at a point that the balls 8a and 8b are pressed into the surface of the cam plate 10 by the locking spring 7, wherein when the balls 8a and 8b engage in the recesses 11 of the lever 2 together with the embossing plate 9 when rotating the cam plate 10 rotates.

The friction plate 12 is rotatably mounted on a shaft 14 which is coaxial with the shaft 1 on a side wall 13 of the device is attached and which cooperates with the shaft 1 at a junction j so that the shaft 1 is freely rotatable.

A timer band 17 is connected to a large gear 18 which is attached to the plate 12 by locking screws 19 is, and guided via a small gear 16, which is on the,

- 10 509818/0845

the same axis as the paper feed roller r3 "is attached, which is rotated continuously in the direction shown by an arrow A by a drive (not shown), so that the plate 12 is rotated in the direction of an arrow B. An Eeder 22, which the side wall 13 over a large washer 20 touches for easy rotation. provided between the side wall 13 and the large gear 18 to the To push plate 12 towards the cam plate 10 so that the cam plate 10, when the closure of the cam plate 10 is released in a manner to be described later, rotates together with the friction plate 12, the cam plate 10 is in sliding contact with the plate 12 during closure. A small washer 23 is between the Lever 2 and the side wall 24 arranged to avoid axial play of the parts described above.

With particular reference to Pig. 3, a lever 28 is arranged below and parallel to the support surface 29 and pivotally connected at its central part to the frame of the device by a pin ρ. The lever 28 has a Extension 28a which extends downwardly at right angles from one end to convert into a nooke 10a of the Engage cam plate 10. The other end 28b of the lever 28 cooperates with a pin 26b which is attached to a locking lever 26 for the support surface, whereby it is at the end 28b of the lever 28 is arranged in a direction perpendicular to the axis of the lever 28 and slid through

- 11 509818/0845

the frame of the device is supported. The upper end 26a of the lever 26 cooperates with a nook 29a which is formed in the underside of the support surface 29, the lever 26 being pressed upwards at its lower end by a pretensioning device, for example by a compression spring u. The lever 28 is normally moved clockwise about the pin ρ by a spring 30 which extends between the lever 28 \ inä of the frame of the device at a control near the end 28b of the lever 28, while a piston 27a of a release spool 27 for the closure of the bearing surface is connected to the lever 28 at a point between the spring 30 and the pin ρ to rotate the lever 28 counterclockwise about the pin ρ when the spool 27 to simultaneously release the closure of the cam plate 10 and the bearing surface 29 is excited.

The r3 in the vicinity of the feed roller disposed microswitch SW1 is provided to the unillustrated drive the bearing surface, the release coil 27 vmä of the closure of the bearing surface to operate currently. The microswitches SW2 and SW3 are arranged in the vicinity of the lever 2, the former being provided for generating a signal for cutting, while the latter is for stopping the excitation of the corona charger OH, the light source L and the feed clutch, not shown, of the support surface and also for Actuation of the reverse clutch, not shown, of the

- 12 5098 18/0845

is provided, the two microswitches SW2 and SW3 should puncture when their actuating ^{devices SW2 1} and SW3 ^{1 are} depressed by lever 2 while lever 2 is rotated in the direction of arrow B. The microswitch SW3 is arranged at a position so that its operating device SW3 ^{1 is} depressed for operation by the lever 2 when the rear edge of the printing paper sheet leaves the exposure position E.

With this arrangement, the adjusting knob k1 for the cutting length is rotated to a position which corresponds to the size of the original P placed on the support surface 29, to the lever 2 on the cam plate 10 by the locking device, for example in a Pig. 3 position shown. When the copy pressure switch PS (Pig. 2) on the control ^{panel W is then depressed, the paper feed rollers r1 J} , r1 and the paper feed rollers r2 *, r2, r3'f r3 _f r4 '»r4, r5', r5 _f rö · , r6 and r7 ', r7, the leading edge of the printing paper web R ¹ reaching the microswitch SW1 through the cutting device C and the pairs of rollers r2', r2 and r3 ', r3. By depressing the actuating device SW1 · by the front edge of the paper web R ¹ , the corona charging device GH and the exposure light source L are energized with the release coil 27 for closing the support surface and the drive, not shown, for the support surface 29

- 13 509818/0845

actuates an electrical circuit not shown. The actuation of the spool 27 causes the lever 28 to rotate by the piston 27a around the pin ρ in the counterclockwise direction, the extension 28a of the lever 28 the crouch 10a of the Cam plate 10 releases and the other end of the lever 23 with the pin 26b of the locking lever 26 of the support surface cooperates so that the lever 26 is pushed downwards to remove the upper end 26a of the lever 26 from the flake 29a of the Pull out support surface 29 and accordingly the closure the support surface 29 to release. The so released from the closure support surface 29 then begins by a drive, not shown, the feed in the scanning device.

At the same time, the cam plate 10, which has been released from the lock by the lever 28 as described above, begins to rotate in the direction of arrow B together with the friction plate 12 and consequently with the lever 2. If, when the lever 2 is turned, the actuating device SW2 ^{f of} the microswitch SW2 is triggered, the rollers r1 'and r1 stop rotating, the cutting ^{device C for cutting the paper web R 1} being operated simultaneously by an electrical circuit not shown, in In this Pail the length of the printing paper R ^{1 to be cut is} determined by the angle of rotation of the lever 2 from its start of rotation to the actuation of the microswitch SW2 and the distance between the cutting device C and the microswitch SW1 along the paper web Ra *.

- 14 509818/0845

After actuating the actuating device SW2 ^{f of} the microswitch SW2, the lever 2 continues to rotate and depresses the actuating device SW3 ^{1 of} the microswitch SW3 at the moment when the rear edge of the cut printing paper leaves the exposure point E in order to excite the corona charger CH and the To terminate exposure lamp L and also to bring a gate thrust coupling, not shown, of the support surface out of engagement, a reversing coupling of the support surface engaging in its place in order to return the support surface 29 in the reverse direction shown by a dashed arrow ν.

When the lever 2 makes one complete turn with the cam plate 10 after actuating the micro-release holder SW3 finished, the extension 28a of the lever 28, which is moved clockwise by the spring 30, engages in the Nooke 10a of the cam plate 10, the rotation of the cam plate 10 and the lever 2 being stopped while the upper end 26a of the Yerschlußstiftes 26 for the support surface, which is urged upwards by the spring device u engages in the recess 29a of the support surface 29. In the meantime, the cut printing paper that through the corona charger CH, the exposure device E, the developing device D and the fixing device F has been processed is output in bin d.

- 15 -

50 9 818/0845

From the above description it is clear that it is possible with the paper cutting device according to the invention is to simplify the construction, so that a compact size and low cost can be achieved because the lever for Adjusting the cutting length one turn in conjunction with the release device for the closure of the support surface makes when the printing paper feed rollers rotate.

In addition, the use of latches for the cut size adjustment knob is extremely effective, to get the desired cut lengths without any individual changes can be made easily and quickly.

In the pig. 5 and 6 is a modified embodiment of the device according to Pig. 3 shown. In this embodiment, instead of the cam plate 10, the friction plate 12, the gearbox 18 and the peder 22 of the embodiment of the Pig. 3 and 4 used a large gear 100 that rotatably mounted on a shaft 1 · and also through the frame 13 and 24 of the device and the wall of the control panel W is rotatably supported, with a washer 20 « is arranged between the transmission 100 and the frame 13 of the device. The locking balls 8a and 8b, which by the Support plate 9 are held against the gear 100 with the latching spring 7 through the hub 3, which is integrally connected to the adjustment lever 2 for the cutting length and on the shaft 1 · through the locking screw

- 16 509818/0845

so "is attached that when the balls 8a and 8b engage in the recesses 11 by turning the adjusting knob k1 to set the desired cutting length of the printing paper Lever 2 is rotated and the rotary movement of the transmission 100 follows. Since the rest of the construction and the mode of operation of the Arrangement of the adjustment knob k1 is the same as that in the embodiment of the Pig. 4, the description is here Abbreviated for simplicity. A chain 101 is passed over the transmission 100 and the small transmission 104 is stationary mounted on the same shaft 105 as a pinion drive 103, which engages in a rack 29b, which is attached to the lower Side edge of the support surface is formed, and the connected to a drive, not shown, via feed and reversing clutches for the support surface, not shown is to transmit the rotary motion of the pinion drive 103 to the large gear 100.

Instead of the combination of levers 28 and 26 in the Pig. 3, an I-shaped lever 26 * is used in this embodiment. The lever 26 * is arranged below and in the vicinity of the support surface 29 and is pivotably connected at one end of its horizontal part to the frame of the copier by a pin p ¹ . At the other end of the lever 26, a locking part 26a ¹ extends upwards at a right angle to the lever 26 *, the tip of which cooperates with a recess 29a which is formed on the underside of the support surface 29.

- 17 509818/0845

The lever 26 'is normally rotated clockwise by the spring 30, which extends between the lever 26 * and the frame of the device, while the piston 27a of the release spool 27 for the closure of the bearing surface with the lever 26 * between the spring 30 and the pin p ^{1 is} connected to rotate the lever 26 'counterclockwise about the pin p ¹ when the coil 27 is energized to release the closure of the bearing surface 29.

When the actuator SW1 ^{f of} the microswitch SW1 (Fig. 1) is ^{depressed by the leading edge of the paper web R 1} in a manner similar to the embodiment of Fig. 3, the corona charger GH and the exposure lamp L are energized, and at the same time the coil 27 actuated to rotate the lever 26 · counterclockwise by the piston 27a, with the locking part 26a ^{1 of} the lever 26 * pulled out of the recess 29a of the support surface and the not shown feed clutch for the support surface, which is connected to the not shown drive , is operated to rotate the pinion 103 in the direction shown by the arrow B to move the support surface 29 in the scanning direction of the arrow a.

With the rotation of the pinion 103 in the direction of the arrow B, the adjusting lever 2 for the cutting length begins to rotate in the direction of the arrow A. When the actuator SW2 ^{1 of} the microswitch SW2 is depressed by the lever 2

- 18 509818 / 08A5

, the feed rollers r1 and r1 stop rotating, and at the same time the cutter C is operated to cut the paper web R ^f , in which case the cut length of the printing paper is determined by the angle of rotation of the lever 2 from the start of its rotation to Actuation of the microswitch SW2 and also by the distance between the cutting device C and the microswitch SW1 along the paper web Ra as in the embodiment of the Pig. 3 and 4 is determined.

The lever 2 rotates after the actuation of the actuating device SW2 ^{1 of} the microswitch SW2 further and depresses the actuating device S ¥ 3 'of the microswitch SW3 at the moment when the rear edge of the cut printing paper leaves the guide plates 17 of the exposure device E to excite the To end corona charger OH and the Belichtongsampe L and at the same time disengage the feed clutch, not shown, of the support surface and instead engage the reverse clutch, not shown, of the support surface and to rotate the pinion 103 in the direction opposite to arrow B and consequently the support surface 29 in the reverse direction, which is shown by a dashed arrow ν, to move. With the reverse rotation of the pinion 103, the lever 2 also rotates in the opposite direction, and when the contact surface 29 has returned to the original closed position, the locking part 26a ^{1 of} the lever 26 being engaged in the recess 29a of the contact surface 29, the pinion will be heard 103 and the

- 19 509818/0845

Lever 2 to rotate, with lever 2 and the support surface 29 have returned to the original printing position.

After passing through the corona charger OH, the Exposure device B, developing device D and fixing device F is the cut printing paper in the meantime has been spent on shelf d.

Although in the embodiment described above, the rack 29b and the pinion 103 for the support surface reciprocating device used, a belt can be used for this purpose, for example a part of the tape attached to the support surface and one Roller is assigned to this.

According to the above description of the embodiment according to the invention 5 and 6, it is possible to make successive copying operations as soon as the support surface is in the original starting position has been returned by the Adjustment lever for the cutting length for actuating the switch that triggers the cutting process through the support surface reciprocating device is returned to the original position for copying.

Since the feed path of the support surface is dependent on is controlled by the cutting length of the printing paper web,

- 20 509818 / 08A5

will also require the support surface more than necessary to move, avoided in an advantageous manner, and the cutting length is completely and quickly through the Adjustment knob set for the cutting length, which is provided with a locking device without any Differences in length occur.

The above description of the present invention, taking into account exemplary embodiments, relates to an electrophotographic copier having a movable platen for placing an original to be copied. It should be noted, however, that the paper cutting apparatus of the present invention is not limited to the copier described above, but is applicable to any electrophotographic copier of the so-called slit exposure type, including those having a movable optical system. When applying the paper cutting device according to the invention to a copier with a movable optical system, the shutter device of the support surface described in connection with the embodiment of FIG. 3 can be used as a shutter device for the movable optical system, and in the embodiment of the Pig. 5-5, the two gears or discs described in connection with the movement of the support surface can be arranged to rotate in connection with the reciprocating movement of the optical system.

- 21 509818/084 5

Claims (8)

2U9684 Claims ( 1. J PapiersclineidevoErichtung for a copier with a reciprocating support surface for an original to be copied and with a copy paper roll, characterized by a first microswitch (SW1) for actuating a drive device of the support surface (29), which runs along one of the copy paper roll ( R) outgoing path (Ra) of a paper web (R ') is arranged and can be ^{actuated by touching the front edge of the paper web (R 1} ) fed by a transport device, by a locking device for holding the support surface (29) in an initial position from which it can be released by a signal from the first microswitch (SW1), by an arrangement with a controllable cam disk (10), by a length adjustment device that can be adjusted step-by-step with a latching device (7, 8a, 8b, 9) for setting a length that corresponds to the original length on the cam disk (10) by means of a length adjustment button (k1), the m it can be moved in one piece with the length adjusting device rotatable with the cam disk (10), by a second microswitch (SW2) which can be actuated by the length adjusting device during the rotational movement of the latter, and by one arranged along the paper path (Ra) and by a signal from the second microswitch (SW2) actuatable cutting device (C) for cutting off the paper web. - 22 509818/0845 2. Paper cutting device according to claim 1, characterized marked that simultaneous with the release by the locking device, the cam disk can be set in rotation and stopped when it is in the Has returned to the initial position. 3. Paper cutting device according to claim 1 or 2, characterized in that the drive device a feed clutch and a reverse clutch for reciprocating the support surface (29), wherein A third microswitch (SW3) for disengaging and engaging the feed clutch through the length adjustment device the reverse clutch can be actuated after actuation of the second microswitch (SW2). 4. Paper cutting device according to claim 1, g e indicates by a locking device (28a, 10a) of the cam disk (10) which is in connection with the actuation of the locking device of the support surface (10) can be released, so that after the release of the cam disk (10) by the locking device (10a, 28a) a single revolution of the cam disk (10) when moving the transport device is feasible, 5. Paper cutting device according to claim 4, characterized gekenn ze ichnet that the closure device of the support surface (29) has a first below and perpendicular - 23 -509818/0845 to the support surface (29) arranged lifting section (26a, 26a ¹ ), the lower end of which is movable by a spring device (u) so that its upper end during the fixing of the support surface (29) in a in the support surface (29) formed recess (29a) engages, and a second below and parallel to the support surface (29) arranged lever portion (28), the pivotable with its middle part on a. Device frame is attached, one end (28a) of the second lever portion (28) engaging with a cam (10a) formed on the cam disc (10) to form the locking device for the cam disc (10), and the second end (28b) of the second Hebeiabschnittes (28) for engagement with the first lever portion (26a) is provided that the second lever portion (28) is rotatable clockwise by a spring (30) and counterclockwise by a solenoid (27) so that when the magnet coil (27) is excited, the first lever section (26a) can be pressed down by the second end (28b) of the second lever section (28) so that the first lever section (26a) disengages from the support surface (29) and the first end ( 28a) of the second Hebeiabschnitts (28) is out of engagement with the cam (10a). 6. Paper cutting device according to claim 4 or 5, characterized in that the held The cam disk (to) is in sliding contact with a friction plate (12) which is synchronized with the transport device - 24 - 509818/0845 is rotatable by a transmission device, so that at released cam disc (10) this is rotatable with the friction plate (12). 7. Paper cutting device according to one of claims 1 to 6, characterized in that the Latching device (7 »8a, 8b, 9) one on the common Shaft (1.V) arranged pedestrian device (7) »a pair by one between the spring device (7) and the cam disk (10) arranged plate (9) held EinrastkugeIn (8a, 8b) and a plurality of locations corresponding to the snap-in balls (8a, 8b) formed on a surface of the cam disk (10) Has recesses (11), wherein by the J spring device (7) the snap-in balls (8a, 8b) can be moved towards the cam disk (10) and into the recesses (11), so that the length adjustment device can be rotated with the cam disk (10). 8. Paper cutting device according to one of the claims 1, 5 or 7, characterized in that the Cam disc (10) in one or the other direction with the back and forth movement of the support surface (29) is movable. - 25 - 509818/0845 Blank page