US3552745A

US3552745A - Rotary transfer mechanism for printing machines

Info

Publication number: US3552745A
Application number: US754038A
Authority: US
Inventors: Josef Jurny
Original assignee: Adamovske Strojirny AS
Current assignee: Adamovske Strojirny AS
Priority date: 1967-08-28
Filing date: 1968-08-20
Publication date: 1971-01-05
Anticipated expiration: 1988-01-05
Also published as: SE348436B; GB1232403A; FR1577820A; DE1786143C3; DE1786143A1; DE1786143B2

Abstract

THE GRIPPERS OF THE TRANSFER MECHANISM ARE ACTUATED BY A SWINGABLE AXLE CARRYING A CONTROL LEVER WITH A ROLLER TRAVELLING IN THE GROOVE OF A CAM. A GUIDE MEMBER IS SLIDABLY MOUNTED IN THE CAM AND IS OPERATED BY A BENT LEVER ACTUATED BY A CAM PLATE SO AS TO IMPART ROCKING MOVEMENT TO THE SWINGABLE AXIS. THE LATTER CARRIES SLEEVES WITH ABUTMENTS FOR GRIPPING THE PAPER SHEET AND WITH FINGERS, ADAPTED TO ENGAGE ABUTEMENT PINS COOPERATING WITH SET SCREWS TO CONTROL THE DEFLECTION OF THE GRIPPERS.

Description

' J. JURNY 3,552,745

ROTARY TRANSFER MECHANISM FOR PRINTING MACHINES Jan.- 5, 1971 Filed Aug. 20, 1968 705 6/ Turn);

7 INVENTOR. I

United States Patent O 3,552,745 ROTARY TRANSFER MECHANISM FOR PRINTING MACHINES Josef Jurny, Sebranice u Kunstatu, Czechoslovakia, as-

signor to Adamovske strojirny, narodni podnik, Adamov, Czechoslovakia Filed Aug. 20, 1968, Ser. No. 754,038 Claims priority, application Czechoslovakia, Aug. 28, 1967, 6,099/67 Int. Cl. B65h 29/06 US. Cl. 271-82 3 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION (1) Field of the invention The present invention relates to a rotary transfer mechanism constituting a device for the transfer of paper sheet into the grippers of a printing roller in rotary sheet printing machines.

(2) Description of the prior art One of the known devices comprises a swingable transfer mechanism with grippers which, having transferred the sheet to the printing roller, return to their original position along a different and slightly elevated path, in order to permit the return movement of the swingable grippers without interference with the passage of the preceding paper sheet over the feeder table. This operation is performed by means of rotary excentric bushings, housing the main shaft of the swingable grippers. This coupled with an independent control of the transfer mechanism, renders the respective mechanism highly intricate. Moreover, during each operative cycle of the transfer mechanisms the latter have to be accelerated from their position of rest when gripping the sheet, to the peripheral speed of the printing roller, then decelerated until they are completely stopped. Thereupon they must be again greatly accelerated during their return movement and again slowed down until they are completely stopped. The rate of acceleration is unfavourable particularly with an arrangement of the machine in which the angle of transfer from the feeder table exceeds 120, as for example in five-roller systems as are used in two-colour printing machines.

For this reason it is necessary to use swingable transfer mechanisms placed at a lower level and having a small angle of oscillation as well as a further transfer drum.

These disadvantages are eliminated by the arrangement of rotary transfer mechanisms, which after acceleration continue their rotary movement until they are stopped. The return movement necessary for gripping the sheet is negligible and connected with a minimum amount of acceleration. Consequently the respective mechanism as well as the proper transfer mechanisms can be lighter in weight, so that at high speed they do not cause such a large impact as the previously mentioned heavy devices. Rotary transfer mechanisms can be employed advantageously also for large angles of transfer, with the result that the further transfer drum may be dispensed with. In connection with such known rotary transfer mechanisms a tiltable "ice It is a disadvantage of this latter device that the entire conveying table, having a large mass, has to be moved within a relatively short time. This is the cause of considerable impact and harmful application of force on the machine.

SUMMARY OF THE INVENTION The present invention aims at removing the aforementioned disadvantages of the known rotary transfer mechanisms. The invention provides a swingable axle carrying, on the one hand pivotally mounted sleeves to each of which is fixed a bar with an abutment plate and, on the other hand, fixed fingers adapted to bear on abutment pins fitted in the sleeves and bearing on set screws, which are arranged in holder secured to carrier discs supporting the axle. Fixed to the swingable axle is a control lever, provided with a roller adapted to travel in the groove of a cam and along a track provided on a guide member placed in a slot of said cam. The guide member is pivotally mounted on a pin fixed to one end of a bent lever. This bent lever, rotatably mounted on a pivot fixed in the sidewall of the machine, is provided at one end with a control screw and with a groove for a safety screw, its other end carrying an eccentric pivot with a follower.

It is an advantage of the rotary transfer mechanisms according to the invention that it is possible to execute the respective mechanisms as well as their drive in a lighter Weight than before, so that impacts occuring at higher revolutions of operation are minimized. The conveying table is stationary and the abutments are made tiltable in order to allow the passage of the grippers through the feeding plane. This arrangement is simple, light in weight and due to the fact that the centre of rotation of the abutment bar is identical with the centre of the gripper mounting, it is sufliciently accurate. Moreover the gap between the abutments of the grippers of the rotary transfer mechanisms and the abutments of the printing roller can easily be adjusted in accordance with the thickness of the sheet to be printed, with the result that its accurate transfer is ensured.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings show, by way of example, one of the possible arrangements of the transfer mechanism according to the invention in a diagrammatic representation.

FIG. 1 is an elevation, partially in section, of the transfer mechanism, the grippers assuming a slightly deflected position,

FIG. 2 is a side view, partly in section taken along the line AA and showing the parts in a position marked I in FIG. 5, and illustrates the position at the moment when the sheet is picked up and the transfer movement begins,

FIG. 3 is a partial section along the line AA from FIG. 1 and represents the position II of the parts, as shown in FIG. 5, and illustrates the tiltable grippers with the abutments prior to leaving the feed plane,

FIG. 4 is a partial section along the line AA from FIG. 1 at the moment when the grippers are opened, and

FIG. 5 shows the device in a section along the line BB from FIG. 1.

3 DESCRIPTION OF THE PREFERRED EMBODIMENT The rotary transfer mechanism according to the invention comprises a main shaft 1 journalled in the sidewalls 20 of a printing machine. Rigidly secured to the main shaft 1 are spaced carrier discs 2, on which a swingable axle 3 is mounted for rotation. As seen in the figure, the axle 3 is parallel to but offset from the axis of the shaft 1. Rockably fitted on the swingable axle 3 are spaced sleeves supporting a bar 9 on which abutment plates 8 are located. Firmly secured to the swingable axle 3 are fingers 13 and holders 5, which are provided with screws 6, springs 7 and swingably mounted grippers 4. Fixed to one end of the swingable axle 3 is a control lever 21 carrying a roller 22 which is journalled on a pin 23 and with a tensile spring 36, suspended on a stud 35 and on a suspension pin 37, which is secured to the carrier disc 2. Each of the sleeves 10 accommodate abutment pins 12, the outer sides of which are engaged by set screws housed in holders 14. Springs 11 are fitted in the sleeves 10 resting against the main shaft 1.

The swingable axle 3 supports the control lever 21 with the roller 22, so that it travels in the groove of a cam 24. A guide member 27 extends into the cam 24 and is rockably mounted on a pin 28, secured in one arm of a bent lever 25. The guide member 27 is further secured in position by a safety screw 29, screwed in said arm of the bent lever 25 and passing through a slot, provided in the guide member 27, so as to allow the adjustment of its position by tilting the guide member 27 about the pin 28. The arm of the bent lever 25 houses further a control screw 30. The bent lever 25 is journalled on a pivot 26 rigidly secured in the sidewall of the printing machine. One end of the bent lever carries an eccentric pivot 32 on which a follower 31 is mounted for rotation, the roller being pressed by a spring 34 against a control cam plate 33. The paper sheets are supplied along a feed table 16 and are held in position by pressure belts 18. Mounted opposite the discharge end of the feed table 16 is a rockable front gauge 17.

The rotary transfer mechanism embodying the invention operates as follows:

The paper sheets having been initially placed and adjusted in proper position, the bent lever 25 (FIG. 5) is shifted by means of the follower 31 during rotation of the cam plate 33 from a position marked III to a position I. Simultaneously the guide member 27 with the aid of the roller 22 and control lever 21 causes the swingable axis 3 to turn in such a way, that the grippers 4, under the action of the pressure spring 7, press the edge of the prepared sheet against the abutment plates 8. In this position a gap remains between the fingers 13 and the abutment 12,. The gap secures the engagement of the abutment pin 12 with the set screw 15 so as to ensure the basic position of the bar 9. After the sheet has been clamped, the front gauge 17 is deflected and the rotary transfer mechanisms start an accelerating movement. The roller 22 passes smoothly from the operative surface of the guide member 27 in position I to the groove, positioned in the cam 24 at the point where the curvature of the groove forms a wave-line, causing the control lever 21 and thus the swingable axle 3 to turn and open the grippers 4, when transferring the sheet to the printing roller 19. The smooth blending of the operative surface of the guide member 27, when in position 1, into the groove of the cam 24 is adjusted by means of the eccentric pivot 32. The spiral shape of the groove in the cam 24 causes during further movement of the control lever 21 another partial rotation of the swingable axle 3, in such a way that the grippers 4 are reclosed. The continuing rotation of the swingable axis 3 causes the finger 13 to abut against the abutting pins 12.

In this way the springs 11 are depressed and the sleeves 10, together with the bar 9 and abutment plates 8, begin to effect a tilting motion so that at the moment when the grippers 4 are in a position above the front gauge 17, they are tilted to a position II (see FIG. 3), to enable the passage of the remaining part of the Withdrawn sheet, while the following sheet is already prepared and properly positioned on the tiltable front gauge 17. The roller 22 of the control lever 21 travels in this position along the operative surface of the guide member 27 in the position II, which joins the groove provided in the cam 24; the smooth blending can be adjusted by means of the set screw 30.

At the moment when the end of the preceding paper sheet has left the feed plane, the rotary transfer mechanisms are already at rest and it is only the bent lever 25 which is in motion by the action of the control cam plate 33 and follower 31 in such a way that the operative surface of the guide member 27 drops from position II into position III. By the action of the roller 22 and control lever 21 the swingable axis 3, as well as the fingers 13, are slightly rotated. This movement causes the abutment pins 12 to engage the set screws 15, with the result that the movement of the sleeve 10, bar 9 and abutment plates 8 is stopped. As, however, the rotary movement of the swingable axis 3 and of the holders 5 continues, the grippers 4 are opened (FIGS. 4 and 5) and after the rotary transfer mechanisms have been turned back and the grippers closed in the manner described above, the whole cycle of operation is repeated.

The drive of the main shaft 1 and consequently also of the transfer mechanisms is derived from a not-illustrated mechanism consisting of cam discs, rollers and toothed segments, which transmit the movement from the printing roller. In order to eliminate any inaccuracy in the transfer which may be caused by the undulation of a thin paper sheet, the gap between the abutment plates 8 may be adjusted by means of the set screws 15 provided with a scale, so as to alter the distance of the abutment plates 8 from the axis of the main shaft 1.

I claim:

1. In a device for the transfer of pre-positioned paper sheets into the grippers of a printing roller in rotary sheet printing machines, a rotary transfer mechanism, comprising a machine frame, a main shaft mounted for rotation in said machine frame, means for imparting rotary movement to the main shaft, spaced carrier discs firmly secured to the main shaft, a swingable axle parallel to said shaft and mounted for rotary movement in said carrier discs, means for imparting partial rotary movement to the swingable axle in relation to the carrier discs, spaced sleeves mounted for rocking movement on the swingable axle, a supporting bar having an abutment plate fixed to each of said sleeves for rocking movement therewith, an abutment pin fixedly mounted in each of said sleeve, a pair of spaced fingers rigidly fixed to the swingable axle and adapted to engage each of the abutment pins respectively, screw means carried by said carrier discs and adapted to engage each of said abutment pins respectively.

2. In a device for the transfer of pre-positioned paper sheets into the grippers of a printing roller in rotary sheet printing machines, a rotary transfer mechanism, comprising a machine frame, a main shaft mounted for rotation in said machine frame, means for imparting rotary movement to the main shaft, spaced carrier discs firmly secured to the main shaft, a swingable axle parallel to said shaft and mounted for rotary movement in said carrier discs, means for imparting partial rotary movement to the swingable axle in relation to the carrier discs, spaced sleeves mounted for rocking movement on the swingable axle, a supporting bar having an abutment plate fixed to each of said sleeves for rocking movement therewith, an abutment pin fixedly mounted in each of said sleeve, a pair of spaced fingers rigidly fixed to the swingable axle and adapted to engage each of the abutment pins respectively, screw means carried by said carrier discs and adapted to engage each of said abutment pins respectively, a control lever is fixed to the swingable axle carrying a roller and includes a grooved cam and a guide member located in a slot formed in said cam, said roller adapted to travel, on the one hand, in the groove provided in a cam and, on the other hand, along the operative surface of a guide member, the guide member being further mounted for adjustment on one arm of a bent lever, controlled by a control cam plate.

3. A rotary transfer mechanism as in claim 2, wherein the bent lever is journalled on a pin fixed in the frame of the machine, and is provided at one end with a control screw and With a groove for a safety screw, its other end being provided with an eccentric pivot carrying a follower, cooperating with said control cam plate.

References Cited FOREIGN PATENTS 602,045 5/1948 Great Britain 27l82 0 RICHARD AEGERTER, Primary Examiner