Drive device for a folder in a printing press

Abstract: A drive device (10) for a folder in a printing press having a folding blade affixed to a folding blade shaft (12) for a folder having a gear (14) for driving the folding blade shaft (12), a drive gear (16) for driving the gear (14) of the folding blade shaft (12), a plunger (24) having an intermediate gear (28) between the gear (14) of the folding blade shaft (12) and the drive gear (16), and a device for moving the plunger (24) between a first longitudinal position with the intermediate gear (28) meshing with the gear (14) of the folding blade shaft (12) and with the drive gear (16) to drive the folding blade shaft (12), and a second longitudinal position with the intermediate gear (28) out of register with the drive gear (16) to prevent the drive gear (16) from driving the gear (14) of the folding blade shaft (12).

Description: The present invention relates to drive devices for a folder in a printing press according to the preamble of claim 1. In order to double a product's page count, rotary folders in a printing press utilize a method of collecting sheets to become a larger product. To accomplish this task, a folding blade shaft is silenced so that it does not perform a tucking operation into nipping folders. This operation permits the product to remain on a cylinder so that it is supplemented with additional materials as a result of the cylinder rotating another revolution. This operation is in contrast to the straight mode during which no folding blades are silent and no products are permitted to remain on the cylinder. US 3 865 361A, which corresponds to the preamble of claim 1, shows a drive device having an intermediate gear displaceable from a first to a second longitudinal position and vice versa to drive or prevent driving of the folding blade shaft. A separate device for axially displace the intermediate gear comprises a rotatable stub shaft extending rectangular with respect to the intermediate gear. The shaft comprises a disc with an eccentric lug extending into an annular groove in the plunger. Upon rotation of the stub shaft the plunger is axially displaced. The object of the present invention is to provide a drive device which is of simplified construction and reduced cost. This object is achieved by a drive device comprising the features of claim 1. A further feature of the invention is the provision of means for releasably locking the intermediate gear in the second position of the plunger which prevents the folding blade from accidentally rotating. Further features will become more fully apparent in the following description of the embodiments of the invention, and from the appended claims. In the drawings: Fig. 1 is a step-by-step description of straight and collect operations of a folder in a printing press; Fig. 2 is a sectional view of a device for driving a folding blade shaft showing indirect engagement of the folding blade shaft with a drive gear; and Fig. 3 is a sectional view of the drive device of Fig. 2 showing the drive gear indirectly disengaged from the folding blade shaft. Figure 1 gives a step-by-step description of straight and collect operations of a typical rotary newsprint folder of a printing press. In the drawings, a 3/2 folder is featured (3/2 means the collect cylinder is sized to hold 3 cutoff lengths of newsprint and the cutting cylinder at 2 cutoffs of newsprint). Various ratios of collect cylinder to cutting cylinder can also be used, i.e., 5/2 and 3/1. Straight Run: The first caption shows the paper being pulled by the collect cylinder. Note that a 2-folding blade mechanism is featured. It rotates at a speed of 3/2 times the folding cylinder. The second caption shows the first paper 101 pulled around the collect cylinder to a precise point whereupon the cutting cylinder, which is timed to the collect cylinder, severs the first paper 101 from the second paper 102. Immediately following the severing operation the first paper is tucked into a nipping roller assembly. The second paper 102 is held to the collect cylinder via pins located on the collect cylinder. The third caption is a repeat operation as the second caption except that the second paper 102 is being tucked into the nipping roller assembly. During the straight operation, every paper is tucked into the nipping roller assembly. Therefor, each folding blade shaft is engaged with the drive gear. Reference sign 103 defines the third paper. Collect Run: The collect operation differs from the straight operation because every other paper is tucked into the nipping roller assembly. Those papers which are not tucked initially remain with the collect cylinder, and are joined with another paper before being tucked into the nipping roller assembly. During the collect operation, one folding blade shaft is disengaged from the drive gear (silenced) to prevent the paper from the tucking operation. In the first caption, the inside section 104 of the first paper 101 is in the tucking position, but the folding blade 105 is silenced, and the collect cylinder pins remain extended into the paper. The cutting cylinder severs the first paper inside section 104 from the succeeding paper's outside section. The second caption shows the first paper's inside section 104 remaining with the collect cylinder, and the succeeding outside section being tucked into the nipping roller assembly. The tucked paper will have no inside section so it is discounted as waste. The silenced folding blade shaft has rotated 180 degrees, and the engaged folding blade shaft creates the tucking action. The third caption shows the first paper's inside section 104 remaining on the collect cylinder, and it is being joined by the outside section 106. Meanwhile, the inside section 107 of the second paper is not tucked into the nipping roller assembly because the engaged folding blade shaft has rotated 180 degrees, and the silenced folding blade shaft is in the tucking position. The fourth caption gives a picture of the first complete paper 108 being tucked into the nipping roller assembly because the silenced folding blade shaft has rotated 180 degrees, and the engaged folding blade shaft is in the tucking position. Simultaneously, the second paper's inside section 107 remains with the collect cylinder, and the third paper's inside section 109 is being pinned onto the collect cylinder. Note that caption 4 is identical to caption 2. The fifth caption is identical to caption 3 except that the second paper is receiving the outside section 110. Likewise, the sixth caption is identical to caption 4 except that the second complete paper 111 is being tucked in to the nipping roller assembly. The inside section of the fourth paper has the reference sign 112. The operation keeps repeating with every other paper being tucked into the nipping roller assembly. The proposed drive in the present application controls the action (engaged or silenced) of the folding blade shafts to which are mounted the folding blades. In the newsprint industry, the printing units may be two cut offs around whereupon the newsprint web will have alternating printed images. Since the collect cylinder is of an odd integer cut off (3, 5, 7, etc.), each inside section will be joined with a different outside section (i.e., B will be joined with A). Referring now to Figs. 2 and 3, there is shown a drive device 10 for a folder in a printing press in the straight and the collect mode, respectively. The device has a rotating folding blade which is mounted on a folding blade shaft 12 for the folder. The folding blade shaft 12 has an outer gear 14 for driving the folding blade shaft 12. The device has a drive gear 16 aligned with the folding blade shaft gear 14 on the folding blade shaft 12. The gear 16 has a central recess 18 defining teeth 20 on one side of the recess 18, and teeth 22 on the other side of the recess 18. The device has an elongated plunger 24 which is slidably mounted in the drive device 10, and which is outwardly biased by a helical spring. The plunger 24 has an intermediate gear 28 which is rotatably mounted on the plunger 24 by bearings 30. In the configuration of Fig. 2, the intermediate gear 28 is meshed with the drive gear 16, and with the folding blade shaft gear 14 in order to rotatably drive the folding blade shaft gear 14 and the folding blade shaft 12 by the intermediate gear 28 and the drive gear 16. The intermediate gear 28 has a central recess 32 defining teeth 34 on one side of the recess 32, and teeth 36 on the other side of the recess 32. A cam 38 is mounted on the outer end 40 of the plunger 24 by a bearing 42 with a boss 44 of the plunger 24 being received in a cam race 46 of the cam 38. A needle bearing carries the reference sign 43, a bushing the reference sign 45, a further bushing the reference sign 47 and thrust bridges the reference sign 49. The plunger 24 is movable from a first longitudinal position shown in Fig. 2 with the gears 14, 28, and 16 being meshed, to a second longitudinal position as shown in Fig. 3 with the intermediate gear 28 being moved forwardly in the drive device 10, with the cam 38 releasably retaining the plunger 24 in the second position. In the second position, the teeth 36 of the intermediate gear are received in the recess 18 of the drive gear 16, and the teeth 20 of the drive gear 16 are received in the recess 32 of the intermediate gear 28. In this configuration, the drive gear no longer drives the folding blade shaft gear 14 since the drive gear 16 is no longer meshed with the intermediate gear 28. In this configuration, a tang 48 mounted on the plunger 24 engages a collar 50 of the folding blade shaft 12 to prevent rotation of the intermediate gear 28 which is no longer meshed with the drive gear 16. The outer end 40 of the plunger 24 is engaged by an actuating member 54 in order to move the plunger 24 from the first position of Fig. 2 to the second position shown in Fig. 3. The outer end 40 of the plunger 24 is actuated again by the actuating member 54 by pushing the plunger 24 after which the spring 26 moves the plunger 24 to the first position shown in Fig. 2 with the intermediate gear 28 engaged with the drive gear 16 in order to drive the folding blade shaft 12. During the movement of the plunger 24 from its second to first position, the cam 38 is rotated by a boss 44 in the cam race 46 in order to permit translation of the gear assembly and to releasably retain the plunger 24 in the first position. Thus, in this manner, the plunger 24 is pushed each time it is desirable to change the configuration of the gears 14, 16, and 28 such that the drive device 10 controls the engagement of the gears to drive the folding blade shaft 12 and disengagement of the gears to stop rotation of the folding blade shaft 12.

Claims: A drive device (10) for a folder in a printing press, comprising: a folding blade affixed to a folding blade shaft (12) for a folder having a gear (14) for driving the folding blade shaft; a drive gear (16) for driving the gear (14) of the folding blade shaft (12); a plunger (24) having an intermediate gear (28) between the gear (14) of the folding blade shaft (12) and the drive gear (16); means for moving the plunger (24) between a first longitudinal position with the intermediate gear (28) meshing with the gear (14) of the folding blade shaft (12) and the drive gear (16) to drive the folding blade shaft (12), and a second longitudinal position with the intermediate gear (28) out of register with the drive gear (16) to prevent the drive gear (16) from driving the gear (14) of the folding blade shaft (12), characterized in that the plunger (24) has a boss (44) and that a cam (38) mounted on an outer end (40) of the plunger (24) and having a cam race (46) is provided; the boss (44) being received in the cam race (46); and, during movement of the plunger (24) from the second longitudinal position to the first longitudinal position, the cam (38) being rotated by the boss (44) received in the cam race (46) to releasably retain the plunger (24) in the first longitudinal position. The device (10) of claim 1, characterized by means (26) for biasing the plunger (24) between the first to second longitudinal position. The device (10) of claim 1 or 2, characterized by means for releasably locking the intermediate gear (28) in the second longitudinal position of the plunger (24). The device (10) of any of the claims 1 to 3, characterized in that the drive gear (16) has a central recess (18) forming a pair of opposed spaced teeth (20, 22), the intermediate gear (28) has a central recess (32) forming a pair of opposed teeth (34, 36), in which one of said pair of opposed spaced teeth (20, 22) of the drive gear (16) is located in the recess (32) of the intermediate gear (28) in the second longitudinal position of the plunger (24), and in which one of said pair of opposed teeth (34, 36) of the intermediate gear (28) is located in the recess (18) of th drive gear (16) in the second longitudinal position of the plunger (24).

Inventors: TOMCZAK CHARLES, TOMCZAK, CHARLES
Applicants: GOSS GRAPHIC SYST INC, GOSS GRAPHIC SYSTEMS, INC.
Application year: 1996
Main classification: B65H45
IPC codes: B65H45