GB2067170A - Folding machine - Google Patents

Abstract

A folding machine, especially for a rotary printing machine, comprises a rotatable cylinder (1) provided with pivotable folding blades (6, 8) arranged in pairs, and controlled by fixed cam discs. The blades (6) which trail in the rotational direction of the cylinder (1) are each actuatable only at product take-over station (A) and the leading blades (8) each only at a product discharge station (B, C or D) by the cam discs. The cam tracks (14, 15) of the cam discs possess actuation zones (34, 35 respectively) with a fall (24 or 25) and a rise (28 or 29). The cam disc for the leading blades (8) is adjustable, eg by bodily rotation, for the purpose of varying the position of the discharge station. <IMAGE>

Description

SPECIFICATION Folding machine The present invention relates to a folding machine with a folding blade cylinder, and has particular reference to a folding machine for a rotary printing machine.

Depending upon whether a third folding or parallel folding unit adjoins the folding blade cylinder of such a folding machine or subsequently a product delivery takes place directly via a blade wheel, the position for product discharge from the folding blade cylinder and thus the actuation of folding blades of the cylinder must be correspondingly varied as a function of the spatial arrangement of such sub-assemblies in the folding machine.

For this purpose it is known, in a manner analogous to that described in US-PS 2 941 798, to dispose, adjacent to an uncontrollable folding edge which trails in the rotational direction of the folding blade cylinder, a leading folding blade which is actuated by a double cam roller co-operating with two cam discs situated alongside each other. Of the two cam discs, one is firmly connected to the machine frame, while the other is rotationally adjustable through an angle CL for the purpose of varying the position of the product discharge. In order to prevent premature release of the products, a, where the angle p encompasses the region of the lower engagement between a fall and a rise of the cam track of the cam disc.From this it follows that a relative rotation of the second cam disc is possible to only a limited extent, so that in this arrangement it is necessary to replace the cam discs in order to realize all the adjustments that may be required. A further disadvantage that may be mentioned is the long pin required for the double cam roller, which in respect of the dynamic aspects of the machine mitigates against an improvement in the machine performance.

As a variant of the described arrangement, it is also known to permanently set the two adjacent cam discs to different positions of a product discharge and to replace the double cam roller by a single cam roller, which is laterally displaceable relative to the two cam discs between positions in which it co-operates with only one cam disc at a time. Here again, the requirement of two cam discs for controlling the product discharge and also the long roller pin are present as drawbacks.

It is also known from DE-PS 676 745 to dispose a respective cam disc at each end of the folding blade cylinder, these cam discs being set to different positions for the product discharge and being optionally coupled to the folding blade spindle. A disadvantage of this arrangement is the increased technical complication of the coupling mechanism and the fact that for the single moved folding blade which is present, two cam discs are necessary.

There is accordingly a need for a folding machine in which a product discharge at any desired position is possible, for example at a third folding or second longitudinal fold, at a parallel folding or second transverse fold or via a blade wheel into a delivery, whereby means for carrying out an adjustment for this purpose shall be functionally reliable, of simple construction, and not require components to be exchanged.

According to the present invention there is provided a folding machine comprising a rotatable cylinder provided around its circumference with a plurality of pairs of pivotable folding blades, the blades of each pair being arranged to respectively lead and trail in a given direction of rotation of the cylinder, a first stationary cam for actuating the trailing blade of each of the blade pairs at and only at an article entraining station, and a second stationary cam for actuating the leading blade of each of the blade pairs at and only at an article discharge station, each of the cams having a blade actuating zone and the second cam being adjustable to vary the position of the discharge station.

In a folding machine embodying the invention, the second cam controlling the leading blades can be rotationally adjusted, without adversely influencing the article entrainment, into any desired setting for the discharge, for example to a third fold, a parallel fold or via a blade wheel into a delivery. In this way it is possible, compared to an arrangement with two overlapping, relatively rotatable cams, to omit one of the cams including its associated roller. Apart from the attendant reduction in manufacturing expenditure, the roller pin can be made shorter and more stable, thus promoting an increase in performance of the folding machine.

In addition, a tedious, manual changing of the cams is no longer necessary.

Further advantages are the universality of application of the folding blade cylinder to different types of folding machine which assures rational manufacture and maintenance of stocks, and also the possiblity of subsequent incorporation into existing folding machines due to the low demands on space.

Finally, an increase in operating convenience and saving of time in changing from one production method to another are possible.

Preferably, the second cam is mounted to be rotatable about its axis and is fixed in a selectable rotational setting by clamping means with respect to a wall member of the machine, the cam having a set of teeth with which a pinion is engageable, the pinion being rigidly connected to a shaft journalled in the wall member.

An embodiment of the present invention will now be more particularly described by way of example and with reference to the accompanying-dràwings, in which: -Figure 1 is a schematic lòngitudinal sec- tional view of à folding blade cylinder and associated cam drives df a folding machine according to the said ehabodir ent,-ånd Figure 2 is a -schmatic end view 'of -the folifihg'blade cylinder and camidrives of Fig.

1.

Referring now to he drawings, -there is shown a folding blade-cylinder 1 minted on a shaft 2 journalled at its ends in two side walls 3 and 4 ofthe foldingmachine. The cylinder is provided around its circumference with four pairs of folding blades 6 and 8, wherein the blades 8 lead, and the blades 6 trail, in the rotational direction of the cylinder as indicated by the arrow in Fig. 2.

Arranged -on the right side of the cylinder 1 is a cam disc 5, which after initial setting is firmly connected to the side wall 3, for contolling the rigid blades 6. Arranged on the left side of the cylinder 1, coaxially with the disc 5, is a rotatably mounted cam disc 7 for controlling the flexible blades 8. The cam disc 7 has a step extending around its entire perimeter, against which bears a clamping element 9 bolted to the side wall 4, the clamping force Of the clamping element being variable by means of bolts 1 0 (Fig. 1).In addition, the cam disc 7 is provided at its perimeter with a set of teeth 11, into which engages a pinion 1 2 firmly connected to a shaft 13, the shaft being journalled in the side wall 4 and being capable of rotational adjustment by means of a fitting tool pushed onto its free end.

The cam discs 5 and 7 (Fig. 1) have can tracks 14 and 1 5 (Fig. 2) respectively, formed by grooves 1 6 and 17, in each of which is engaged a cam roller 20 or 21 rotatably journalled on an arm 18 or 19, the arms 18 and 1 9 being rigidly connected to the blades 6 and 8, respectively. In Fig. 1, for reasons of clarity, the arms 1 8 and 1 9 are indicated in a rotated position so that rollers 20 and 21 appear out of engagement with the grooves 16 and 17.

As shown in Fig. 2, the cam tracks 14 and 1 5 have actuation zones 34 and 35, respectively, each equipped with a fall 24 or 25 and a rise 28 or 29, respectively. An upper engagement 23, which completes the cam track 15, and a lower engagement 27, should be so designed that each leading blade 8 is opened at a product discharge station B, C or D and is closed again before a product entraining station A. An upper engagement 22 and a lower engagement 26 of the cam track 14 controlling the trailing blades 6 should be so chosen that the blades 6 are not opened until the region of the position D and are closed again at the station A.

As already mentioned, the cylinder 1 has four blade pairs, which are displaced at 90 from each other (Fig. 2), although a different number' of folding blade pairs may be selected according to thé particular application. In each case, at 'the station A product transfer from a folding knife cylinder 30 is carried out with simultaneous transverse 'folding of the product through co-operation of-a folding knife 31. of the cylinder 30with the blades 6 and 8 of the cylinder 1. However, only the previously opened, trailing blade 6 is actuated, i.e.

closed, in such a manner as to engage the product, while the respective leading blade 8 remains in the closed position. The cam disc 7 is so set that the leading blade 8 is opened only at the station B for product discharge whereas she associated trailing blade 6 remains in the closed position. Subsequently, the released product is conducted between conveyor belts 32 and strippers 33 to a delivery via blade wheel (not shown).

By loosening the bolts 10 and thus the clamping element 9, the cam disc 7 can be so rotationally displaced by means of a tool that fits onto the shaft 1 3 of the pinion 12 that the blades 8 are opened either at the point C for product discharge to a third folding or second longitudinal fold unit or at point D for product discharge to a parallel folding or second transverse fold unit.

Claims (6)

1. A folding machine comprising a rotatable cylinder provided around its circumference with a plurality of pairs of pivotable folding blades, the blades of each pair being arranged to respectively lead and trail in a given direction of rotatidn of the cylinder, a first stationary cam for actuating the trailing blade of each of the blade pairs at and only at an article entraining station, and a second stationary cam for actuating the leading blade of each of the blade pairs at and only at an article discharge station, each of the cams having a blade actuating zone and the second cam being adjutable to vary the position of the discharge station.

2. A machine as claimed in claim 1, wherein the actuating zone in each cam comprises a respective fall and rise in a cam track.

3. A machine as claimed in either claim 1 or claim 2, wherein the second cam is mounted to be rotatable about its axis and is secured in a selected rotational setting by clamping means.

4. A machine as claimed in claim 3, comprising a pinion engaging teeth of the second cam, the pinion being rotatable to adjust the rotational setting of the second cam.

5. A machine as claimed in claim 4, wherein the second cam is clamped by the clamping means to, and the pinion is mounted on a shaft journalled in, a wall member of the machine.

6. A folding machine substantially as here it before described with reference to the accompanying drawings.