Device for guiding sheets in a printing press

Abstract

The invention relates to a device for guiding sheets in a printing press, comprising a comb-shaped edge (4) with teeth (5) located near a cylinder (1). The teeth (5) are each assigned a rocker (8) on their back side, which is loaded by a spring (16) and partially blocks a gap (27) between the respective tooth (5) and the cylinder (1) during normal operation.

Description

Technical Field

[0001] The invention relates to a device for guiding sheets in a printing press, which device comprises a comb-shaped edge with teeth located near a cylinder. Background Art

[0002] In such devices, a gripper protruding from the drum runs through the gaps between the teeth, and the teeth guide the sheet.

[0003] A device of the type mentioned at the outset is described in EP 0 922 576 B1. In such devices of the prior art, the comb edge is formed by a set-on element. Summary of the invention

[0004] The object of the present invention is to provide a further device for guiding sheets in a printing press.

[0005] This object is achieved by a device for guiding sheets in a printing press, comprising a comb-shaped edge with a plurality of teeth located near a cylinder, characterized in that the teeth are each assigned a rocker on their back side, which rocker is loaded by a spring and which partially blocks / interrupts the gap between the corresponding tooth and the cylinder during normal operation.

[0006] An advantage of the device according to the invention is that the device has a high degree of operational safety. An additional advantage is the good suitability of the device for complex printing materials.

[0007] The following developments of the device according to the invention can be realized individually and in any combination with one another:

[0008] The pivot lever can be mounted so as to be pivotable about a joint having a pivot joint.

[0009] The shaft head can be guided displaceably in the elongated hole.

[0010] The rocker can have a first arm, a second arm, and a third arm.

[0011] When the rocker is adjusted to a certain position, the first arm can be located between the fork arms arranged on the corresponding teeth.

[0012] The second arm may be loaded by the spring.

[0013] When the rocker is adjusted to a certain position, the third arm can be supported on the stopper.

[0014] The stop can be adjusted by means of a screw.

[0015] The rocker can be made of plastic.

[0016] Foreign matter or wrinkles that penetrate into the gap between the rocker and the drum can cause the rocker to oscillate and / or shift and can cause the gap to increase in size. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The improved scheme is also derived from the following embodiments and accompanying drawings. The accompanying drawings show:

[0018] Figure 1 : Two rollers with associated sheet guiding devices;

[0019] Figure 2 , Figure 3 and Figure 4 : In different locations Figure 1 A rocker for a sheet guiding device in the apparatus;

[0020] Figure 5 : Figure 1 a comb-shaped edge of a sheet guiding device in the sheet guide; and

[0021] Figure 6 : Figure 5 A local spatial view of the comb edge in . DETAILED DESCRIPTION

[0022] Figure 1 The first cylinder 1 and the second cylinder 2 of the printing press are shown. During printing, the first cylinder 1 transfers the sheet to the second cylinder 2. A guide 3 for the sheet is arranged below the second cylinder 2. The edge 4 of the guide 3 extends between the cylinders 1, 2.

[0023] Figure 5 and Figure 6 It is shown that the edge 4 is comb-shaped and has an arrangement of teeth 5 and recesses 6. The gripper 7 of the first cylinder 1, which holds the sheet on its front edge, passes through these recesses 6 during printing operation. Every other tooth 5 of these teeth 5 (i.e. every second tooth 5) is equipped with a rocker 8. The rocker 8 can be swung about a hinge 9 with an axle head 10. The axle head 10 is fixedly located in the rocker 8 and the rocker 8 can be moved along an elongated hole 11, which guides the axle head 10 here. In this way, the rocker 8 is supported on both sides in each side wall 25. The rocker 8 can be swung into a position between the two fork arms 12 ( Figure 3 ), the two fork arms 12 are arranged on the back side of the tooth 5.

[0024] Figure 2 , Figure 3 and Figure 41, the rocker 8 has a profile with a first arm 13, a second arm 14 and a third arm 15. The first arm 13 and the third arm 15 are approximately in a straight line, and the second arm 14 is oriented approximately perpendicular thereto. The second arm 14 is supported on a spring 16, which is supported on a support 17 under prestressing. The third arm 15 is in normal operation ( Figure 2 ) is supported on a stop 18, which can be adjusted by rotating a screw 19. When adjusting the stop 18, the stop 18 is swung around the hinge 20.

[0025] The pivoting path of the stop 18 is limited by the edge 21 of the hole 22, on which the pin 23 abuts. The pin 23 is located fixedly in the stop 18 and engages with play in the hole 22 for the pivoting movement of the stop 18.

[0026] The screw member 19 can be accessed by a socket wrench through the opening 24 in the third arm 15. By adjusting the stop 18, the distance between the rocker 8 and the first roller 1 is determined and manufacturing tolerances of the toothing 5 are compensated.

[0027] Figure 2 is based on Figure 5 The view of the section line II-II shown in FIG. 1 shows the device in normal operation without interference. Here, the spring 16 presses the rocker 8 about the hinge 9 against the stop 18. As a result, the free end 26 of the first arm 13 is positioned approximately centrally in the gap between the fork arm 12 on the one hand and the circumference of the first drum 1 on the other hand.

[0028] In this way, it is prevented that a sheet which has been caught by the second roller 2 and has left the first roller 1 will enter this gap while forming waves or wrinkles. The sheet can be supported on the free ends 26 of the fork arm 12 and the first arm 13. In normal operation, the fork arm 12 and the rocker 8 together block the gap 27 between the tooth 5 and the roller 1, but only partially, because two free spaces remain between the fork arm 12 and the rocker 8 and between the rocker 8 and the first roller 1. The gap width of these free spaces is in the range of about 1 mm to 1.5 mm, which is so small that these free spaces do not impair the sheet-supporting function of the fork arm 12 and the rocker 8.

[0029] Figure 4The device is shown when a paper wrinkle occurs during the printing run. If there is no countermeasure, there is a risk of damaging the device or the adjacent cylinder surface when the wrinkled sheet hits the free end 26. The countermeasure is to allow an evasive movement of the rocker 8. As the pressure exerted by the wrinkle on the free end 26 increases, the rocker 8 moves downward in the direction predetermined by the elongated hole 11 in the side wall 25, which is opposite to the restoring effect of the spring 16. When the rocker 8 moves downward, the spring 16 is strongly compressed and the third arm 15 remains in contact with the stop 18.

[0030] After the movement, the free end 26 is no longer at approximately the same height as the end of the fork arm 12, but forms a step with the end of the fork arm 12. In this way, the spacing between the rocker 8 and the first roller 1 is the same as in normal operation ( Figure 2 ) is increased so that a paper wrinkle can pass between the two without causing damage. The support mode of the rocker 8 is designed so that the minimum distance between the cylinder circumference and the rocker 8 increases due to the entry of foreign matter (such as paper wrinkles) that causes the rocker 8 to move.

[0031] Figure 3 shows the reverse operation of the press The device is used to remove wrinkles from paper. Here, the wrinkles hit the rocker 8 from below, which thus performs an evasive movement about the hinge 9. The wrinkles hit the face of the first arm 13 facing the first roller 1, whereby the rocker 8 moves with reference to Figure 3 Swing counterclockwise around the hinge 9. Here, the third arm 15 is lifted from the stop 18 and the spring 16 is slightly compressed.

[0032] By this pivoting, the free end 26 of the first arm 13 enters between the fork arms 12 and rests on the teeth 5. As a result, the gap or gap 28 between the fork arms 12 and the circumference of the first cylinder 1 is opened to the greatest extent possible, so that the wrinkled sheets can be transported through the guide device 3 without risk during rhythmic operation.

[0033] exist Figure 3 and Figure 4 The evasion movement shown in FIG. 1 can be performed by one rocker 8 on only one tooth 5 or by multiple rockers 8 on multiple teeth 5 simultaneously, depending on the size and location of the paper wrinkle. The rocker 8 returns to its original position ( Figure 2 ).

[0034] The rocker 8 can be made of a relatively soft plastic to prevent the first roller 1 from damaging the sensitive circumference of the first roller 1 when it comes into contact with the rocker 8. Such a contact is conceivable as a result if the spacing between the free end 26 of the first arm 13 of the rocker 8 and the circumference of the first roller 1 is incorrectly calibrated.

[0035] Reference numerals list

[0036] 1 Roller

[0037] 2 Rollers

[0038] 3. Boot device

[0039] 4 Edge

[0040] 5 teeth

[0041] 6 vacancies

[0042] 7 Grabber

[0043] 8 Joystick

[0044] 9. Articulation

[0045] 10 Axis head

[0046] 11 Long hole

[0047] 12 Fork arm

[0048] 13 Arm

[0049] 14 Arm

[0050] 15 Arm

[0051] 16 Spring

[0052] 17 Support

[0053] 18 Stopper

[0054] 19 Screwdriver

[0055] 20 hinge

[0056] 21 Edge

[0057] 22 holes

[0058] 23 Pins

[0059] 24 Opening

[0060] 25 Sidewall (Wange)

[0061] 26 end

[0062] 27 Gap

[0063] 28 Gap

Claims

1. A device for guiding sheets in a printing press, the device comprising a comb-shaped edge (4) with teeth (5) located near a cylinder (1), It is characterized in that The teeth (5) are each assigned a rocker (8) on the back side of the teeth, which is designed to be able to pivot relative to the teeth (5). The rocker (8) is loaded by a spring (16), and During normal operation, the rocker (8) partially blocks the gap (27) between the corresponding tooth (5) and the drum (1).

2. The device according to claim 1, It is characterized in that The rocker (8) is supported in a manner so as to be able to pivot about a hinge (9) having a shaft head (10).

3. The device according to claim 2, It is characterized in that The shaft head (10) is guided in a displaceable manner in the elongated hole (11).

4. The device according to claim 1, It is characterized in that The rocker (8) has a first arm (13), a second arm (14) and a third arm (15).

5. The device according to claim 4, It is characterized in that When the rocker (8) is adjusted into a position, the first arm (13) is located between the fork arms (12) arranged on the corresponding teeth (5).

6. The device according to claim 4, It is characterized in that The second arm (14) is loaded by the spring (16).

7. The device according to claim 4, It is characterized in that When the rocker (8) is adjusted into a position, the third arm (15) is supported on a stop (18).

8. The device according to claim 7, It is characterized in that The stop (18) can be adjusted by means of a screw (19).

9. The device according to claim 1, It is characterized in that The rocker (8) is made of plastic.

10. The device according to any one of claims 1 to 9, It is characterized in that Foreign matter or wrinkles entering the gap (28) between the rocker (8) and the drum (1) cause the rocker (8) to swing and / or move and cause the gap (28) to increase.

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