GB2122975A

GB2122975A - Folding apparatus

Info

Publication number: GB2122975A
Application number: GB08318378A
Authority: GB
Inventors: Oskar Birke; Kurt Sehan
Original assignee: Kombinat Polygraph Werner Lamberz VEB; Polygraph Leipzig Kombinat Veb
Current assignee: Kombinat Polygraph Werner Lamberz VEB; Polygraph Leipzig Kombinat Veb
Priority date: 1982-07-08
Filing date: 1983-07-07
Publication date: 1984-01-25
Also published as: DD218750A3; SU1291447A1; FR2529831A1; GB8318378D0; FR2529831B3; DE3312039A1; DE3312039C2; GB2122975B

Abstract

Folding apparatus comprises a longitudinal folding device (1), a first transverse folding device consisting of a folding blade cylinder (2) provided with spikes or grippers and of a folding flap cylinder (3), and a second transverse folding device consisting of a gripper folding blade cylinder (4) and a folding flap cylinder (5). A tape transport device, which consists of an upper tape (6) partially encompassing the circumferential surface of the folding flap cylinder (3) and of a lower tape (9) partially encompassing the circumferential surface of the gripper folding blade cylinder (4), is arranged between the first and the second transverse folding device for the further guidance of products transversely folded once, and a stripper (12) on the folding flap cylinder (3) of the first transverse folding device is arranged in operative connection with the lower tape (9). <IMAGE>

Description

SPECIFICATION Folding apparatus The present invention relates to folding apparatus with longitudinal folding means and two succeeding transverse folding means, apparatus of this kind being of particular value in high-speed rotary newspaper printing machines which are additionally equipped for book and pamphlet production.

Folding apparatus are known with two transverse folding devices which are arranged one behind the other and in which the first transverse folding device consists of a folding blade cylinder provided with spikes or grippers and a folding flap cylinder and the second transverse folding device consists of a gripper folding blade cylinder and a folding flap cylinder. Such folding apparatus have the advantage that they permit a compact construction with a good accessibility for the operating personnel. In addition, they incorporate an uncomplicated, insensitive and functionally reliable first transverse folding device which is able to provide printing products with a first transverse fold even at maximum printing speed of the rotary newspaper printing machine.

The requirement of many printing works to produce a newspaper transversely folded twice with the newspaper heading lying at the outside can also be met by these folding apparatus.

However, a substantial disadvantage of these folding apparatus, which occurs particularly in high-speed rotary printing machines, is that the folding speed of the second transverse folding device is substantially lower than that of the first transverse folding device, so that printing products with two transverse folds can be produced only with a reduced printing speed.The cause for this lies in the complicated cam control of the grippers, which are arranged in the gripper folding blade cylinder and which, on rotation of the cylinders, must seize the printing product at the instant of the most favourable distance between the folded back of the product held by the folding flaps on the folding flap cylinder of the first transverse folding device and the gripper folding blade cylinder of the second transverse folding device and take it out of the folding flaps opened at the same instant. For this purpose, the opening angle of the grippers must be kept very large and the control angle very small in view of the unfavourable geometric relationships, so that even at low folding speeds, high acceleration values and mass forces arise, which are difficult to manage with increasing rotational speeds.Moreover, the products to be seized by the grippers can be damaged in the case of a small displacement relative to their basic setting.

According to the present invention there is provided folding apparatus comprising first transverse folding means comprising two cylinders co-operable to provide a first transverse fold in the product, second transverse folding means comprising two cylinders co-operable to provide a second transverse fold in the product, conveyor means to convey the product from the first to the second transverse folding means, the conveyor means comprising an upper band extending partly around an output one of the cylinders of the first transverse folding means and a lower band extending partly around an input one of the cylinders of the second transverse folding means, and a stripper operatively associated with the lower band to strip the product from the output cylinder of the first transverse folding means for transfer to the conveyor means.

Such folding apparatus may be used for a rotary newspaper printing machine, and preferably, downstream of a longitudinal folding means, the first transverse folding means comprises a folding blade cylinder provided with spikes or grippers and a folding flap cylinder and the second transverse folding means comprises a gripper folding blade cylinder and a folding flap cylinder. The upper band or tape can then partially encompass the shell surface of the folding flap cylinder of the first transverse folding means, one running surface of the upper belt preferably being the shell surface of the gripper folding blade cylinder, and the lower band or tape can partially encompass the shell surface of the gripper folding blade cylinder. The stripper can be arranged in operative connection with the lower belt on the folding flap cylinder of the first transverse folding means.

Folding apparatus embodying the present invention may have the advantage that the grippers of the gripper folding blade cylinder no longer have to take over the printing products transversely folded once at the instant of the most favourable geometric setting of the cylinders and directly in co-operation with the folding flaps of the folding flap cylinder of the first transverse folding means, but instead have time to take over the products supplied through the stripper and the conveyor means over the entire range of the shell surface, encompassed by the lower belt, of the gripper folding blade cylinder. This results in significantly better conditions for the functional course of movement of the grippers so that a larger control angle and a smaller cam stroke connected with far lower acceleration values can be achieved.Due to the fact that the shell surface of the gripper folding blade cylinder is also used as a running surface for the upper belt, a particularly precise feeding of printed products to this cylinder can be obtained. It is advantageous in this connection that the folding flap cylinder of the first transverse folding means is partially looped around by the upper belt, which ensures a secure transport of the products from this cylinder to the succeeding gripper folding blade cylinder.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawing, the single figure of which is a schematic side elevation of folding apparatus embodying the invention.

Referring now to the drawing, there is shown folding apparatus comprising a longitudinal folding device, which in the illustrated embodiment is a folding funnel 1, a first transverse folding device with a folding blade cylinder 2 and a folding flap cylinder 3, and a succeeding second transverse folding device with the gripper folding blade cylinder 4 and the folding flap cylinder 5.

A tape transport device is arranged between the two transverse folding devices. It consists of a driven upper band 6, which partially encompasses the shell surface of the cylinder 3 and which comprises tapes 7 guided by rollers 8 and by the shell surface of the cylinder 4, and of a lower band 9, which partially encompasses the cylinder 4 and which comprises tapes 10 guided by rollers 11.

A stripper 12 is disposed on the cylinder 3. Also present are a tape transport device 14, which leads to a bucket wheel 1 3 and a blade cylinder 15.

In use, a printed web of paper is guided by way of the funnel 1 and in that case is longitudinally folded. The longitudinally folded web is fed through inlet rollers to the cylinder 2 and the cylinder 15 and is cut by the cylinder 1 5 to product length. Each of the thus cut printed products is entrained by spikes of the cylinder 2 and transported on its shell surface until a first transverse fold is effected through dipping of a folding blade of the cylinder 2 into a folding flap of the succeeding cylinder 3.

The transversely folded product is then seized by folding flaps of the cylinder 3 with simultaneous retraction of the spikes and conveyed on the cylinder 3 after rotation through an angle of, in the present embodiment, about 1200 to a position below the upper band 6. It is then transported between the band 6 and the shell of the cylinder 3 until raised off the shell by the stripper 12 after previous opening of the folding flaps. Thereafter, the product is transported between the bands 6 and 9 until reading the cylinder 4.There, the product is taken over by the grippers of the cylinder 4 in the region of the shell surface encompassed by the tapes 10 and, lying on the back of the cylinder 4, it is conveyed until it is provided with a second transverse fold in the second transverse folding device by functional cooperation of a folding blade of the cylinder 4 with a flap pair of the cylinder 5, the product being seized by this flap pair in temporally consecutive, functional connection with the other movement elements, for example grippers, folding blades and so forth. Finally, the product is conducted lying on the shell of the cylinder 5 to the tape transport device 14 and by this to the bucket wheel 13 for deposition of the product.

By virtue of the described mode of transfer of the printing products transversely folded once from the folding flap cylinder of the first transverse folding device to the gripper folding blade cylinder, more favourable control cams can be employed for the functional gripper movement so that a speed reduction of the second transverse folding device relative to the first transverse folding device is not required and a secure transfer, free of damage, of the printing products transversely folded once through the grippers of the gripper folding blade cylinder is ensured.

Claims

1. Folding apparatus comprising first transverse folding means comprising two cylinders cooperable to provide a first transverse fold in the product, second transverse folding means comprising two cylinders co-operable to provide a second transverse fold in the product, conveyor means to convey the product from the first to the second transverse folding means, the conveyor means comprising an upper band extending partly around an output one of the cylinders of the first transverse folding means and a lower band extending partly around an input one of the cylinders of the second transverse folding means, and a stripper operatively associated with the lower band to strip the product from the output cylinder of the first transverse folding means for transfer to the conveyor means.

2. Folding apparatus as claimed in claim 1, wherein the first and second transverse folding means each comprise an input folding blade cylinder provided with product engaging elements and an output folding flap cylinder.

3. Folding apparatus as claimed in either claim 1 or claim 2, wherein the upper band additionally extends partly around the input cylinder of the second transverse folding means.

4. Folding apparatus substantially as hereinbefore described with reference to the accompanying drawing.