GB2177645A - Cross perforator - Google Patents

Abstract

Across perforator for a web fed printing press includes a plurality of different diameter perforator cylinders 35-39 carred in spaced apart discs 7,7' which are themselves carried in side frames 2, 3. The discs can be rotated in the side frames to select anyone of the perforator cylinders to contact an anvil cylinder 52. Means 33, 23 are provided for locking the discs against rotation and for locating accurately the selected perforator cylinder. Each perforator cylinder carries its own driven gearwheel to accept drive from a common driving gear 51 when that perforator cylinder is brought to an operating position. <IMAGE>

Description

SPECIFICATION Improvements in perforating mechanisms The present invention relates to perforating mechanisms and more specificallyto cross perforators used in web fed presses.

It is frequently desirable to provide different repeat print lengths on a web fed press and to cross perforate between the end of one print length and the beginning ofthe next. Forexamplewith a printing plate having a printing length of 24inches itis possible to print repeat print lengths of 2 x 12 inches, 3 x 8 inches and so forth, a perforation being provided between each print length.

To effect perforation, a perforating cylinder of the same diameter as the printing cylinder may be provided, the cylinder having a plurality of slots to receive perforator blades equi spaced aboutthe circumference ofthe cylinderto accord to the repeat print lengths of the plate on the printing cylinder.

The provision of such a cylinder is difficultto manufacture and precludes the replacement of perforator blades into the cylinderwhen the press is in operation, for another run of different print length.

According to the present invention there is provided a cross perforator for a web fed printing press including two laterally spaced side frames each supporting a disc between which are located a plurality of cylinders each of different diameter carrying perforators means being provided to index the discs to a position to bring a perforating cylinder of desired diameter into contact with an anvil cylinder andatthesametimeengagedriven meanstothe selected cylinder to drive mechanism on the printing press, further means being provided to lock the discs in the selected position relatively to the side frames.

The invention has particular application to a business forms press which is capable of quick changes of repeat print lengths.

In the accompanying drawings which show one example of perforating mechanism according to the present invention; Figure lisa plan view ofthe mechanism Figures2and 3are left and right side elevations respectively Figure 4 is a detail of a locking mechanism and Figure 5is a front elevation of the mechanism Printing press side frames, generally designated 1 supporttwo side frames 2, 3: the side frames 2,3 are bolted to the press side frames by bolts 4.

If desired a locating pin, not shown, may befitted into each printing press side frame and locate into the perforating mechanism side frame positioned above it. The holes in the side frames 2,3 through which pass the bolts 4 may be elongated to allow a little adjustment ofthe side frames 2,3 when they are assembled onto the printing press side frames 1.

The side frames 2,3 each has a hole 5,5' cut through it and a radial slot 6,6' cut from holeto outer edge of the side plate.

Discs 7,7' are fitted into the holes 5,5' and are a sliding fit therein.

To each disc 7 7' is respectively secured a cog wheel 8,8'.

Cog wheels 8,8' are of larger diameter than the discs 7,7'; An axle 9 extends between the discs 7,7'.

The cog wheels 8,8' act as bearing surfaces for rotation of the discs 7,' relatively to the side frames 2, 3.

Rotation ofthe discs 7,7' is effected by cog wheels 10,10' which are pinned externally of the sideframes 2,3 to a shaft 11 which extends between the side frames.

The shaft 11 has a bifurcated end 12 forthe reception of a handle, not shown, ortommy bar.

The discs 7,7' are located and locked in that located position by means of a spring loaded plunger 13, which enters one of a plurality of holes 14which are very accurately located in the disc 7, relatively to the perforating cylinders, The holes are preferably lined with a hard wearing bush, not shown.

The plunger 13 is carried in a housing 15, screwed to the side frame 2. The housing 15 has a bore 16 into which is screwed a bush 17 having a cross slot 18.

Plunger 13 has a collar 19 pinned to it. Between the collar 19 and a ledge 20 on the bush 17 is a helical spring 21. Plunger 13 has a pin 22 passing through it.

A handle 23 is secured to the outer end ofthe plunger 13.

To unlockthe discs 7,7', the handle 23 is pulled outwardly away from the side frame 2, against the action ofthe spring 21, pulling the pin 22 out ofthe slot 18. A 90 turn ofthe handle 23 locks the plunger in its "out" position, as the pin 22 rests on the surface of the bush 17.

The discs 7,7' are locked in any indexed position by locking means which act positivelyto open or close the slots 6 6' in the side frames 2,3.

The locking means comprises lower blocks 24,24' screwed respectively to the side frames 2,3.

Upper blocks 25,25' are screwed respectively to the side frames 2,3.

Pillar blocks 26,26' are respectively screwed to the upperfaceofthesideframes2,3.

The upper blocks 25,25' have a screwthreaded bore receiving a screwthreaded portion 27,27' of long screws 28,28'.

The screws 28,28' extend through the pillar blocks 26,26' attheir upper end to the lower blocks 24,24' where they pass through bearing blocks 29,29' nesting in cut outs in the lower blocks 24,24'.

Nuts 30,30' are respectively screwed to the bottom ends of the screws 28,28'. Bearing collars 34,34' are pinned to the screws 28,28' above the lower blocks 24,24'.

The upper ends of the screws 28,28' have secured thereto stub arms 31,31 ',to which is pivotally secured a link 32.

Shand lever33 is secured to the stub arm 31.

Movement of the hand lever 33 moves the stub arms 31,31 ' through link32,to rotate the screws 28, 28'.

Rotation of the screws 28,28' causes the threaded portions 27,27' to move up or down relatively to the upper blocks 25,25' such movement positively pulling or pushing on the lower blocks 24, 24', opening or closing the slots 6,6' and hence unlocking or locking the discs 7,7' against movement.

Extending between the discs 7,7' is a series of perforator cylinders 35,36,37,38 and 39. Each perforator cylinder is of different diameter, the diameters corresponding to the preferred repeat cut off print lengths required by a printer.

Each cylinder is carried in bearings respectively 40, 41,42,43 and 44 in disc7 and 40'41'42' 43' and 44' in disc7'.

Only one perforator blade 45 is shown; the perforator blades may be secured in the perfora cylinders by any known means, and each perforator cylinder may contain more than one perforator blade axially circu mferentially spaced apart.

The journals of cylinders 35,36,37,38 and 39 extend through the disc 7' and have respectively secured thereto gear wheels, 46,47,48,49 and 50.

As the discs 7,7' are rotated, so the gear wheels are brought into driving mesh with a driving gear 51.

Driving gear 51 also drives an anvil cylinder 52 carried in bearings 53,53' mounted in the side frames 1 ofthe printing press.

In operation, a printerwill first selectthe repeat print cut-off length the printing job requires. This cut off length will be matched by one of the cross perforator cylinders.

The printeruniocksthe discs7,7' bypullingthe hand lever 33, rotating the screws 28,28' to force open the slots 6,6' by acting on the upper and lower blocks 25,25' and 24,24'.

With the slots 6,6' forced apart, the discs 7.7' are free to rotate.

The handle 23 is pulled out, releasing the plunger 13from a hole 14,the handle 23 is rotated through 90" to retain the plunger in the unlocked condition.

The shaft 11 is then rotated, rotating gears 10, 10' to rotate the gearwheels 8, 8'to bring the required perforator cylinder into co-operation with the anvil cylinder 52, whence the handle is again rotated through 900 to release the plungerto locate into the hole 14which is very accurately located in relation to the selected perforator cylinder.

Locking the discs 7,7' is then effected by pushing the hand lever 33 to close the slots 6,6', clamping the discs.

If desired individual clamping means may be provided to open and close the slots 6,6'.

The locating mechanism can be modified as by the provision of a solenoid to withdraw the plunger 13 and the discs 7,7' can be motor driven.

Solenoids may be employed to swing the stub arms 31,31' thereby locking or unlocking the discs 7, 7'.

Bytheforegoing means the selection of a particular cross perforator can be entirely automatic. For example, each ofthe cross perforator cylinders can be given a push button, or its number indicated on a dial, such that on selection, and circuit energisation the following actions will take place sequentially, the plunger 13 will be withdrawn by its associated solenoid from one of the location holes 14, the slots 6, 6' will be widened by the action of the screws 28,28' being rotated by the solenoids acting on the stub arms 31,31' and the motor driving the shaft 11 is energised.

The motor can be indexed so that a given number of revolutions will bring the required perforator cylinder into the required position, or a simple optical scanner can read indica on one of the discs, the scanner deenergising the motorwhen the required perforator is in its operative position.

When the perforator cylinder selected reaches its correct location the solenoid which has withdrawn the plunger 13 is deenergised, allowing the plungerto locate in the hole 14 associated with that perforator cylinder and the discs 7,7' are locked against movement by the action ofthe solenoids on the screws 28,28' closing the slots 6,6'.

Claims (13)

1. Across perforator for a web fed printing press including two laterally spaced side frames each supporting a disc between which are located a plurality of cylinders each of different diameter carrying perforators, means being provided to index the discs to a position to bring a perforating cylinder of desired diameter into contact with an anvil and at the same time engage driven means of a perforating cylinder to drive mechanism on the printing press, further means being provided to lock the discs in the selected position relativelyto the sideframes.

2. Across perforatoraccording to Claim 1 wherein there is provided locating means to ensure that a selected perforating cylinder is accurately located and held in that located position relativelyto the anvil with which it cooperates.

3. Across perforatoraccording to Claim 1 wherein there is provided locating means which includes a plunger, mounted on a side frame ofthe cross perforator and capable of location in a hole in one of the discs, which hole is accurately located relativelyto a perforating cylinder associated with it.

A. Across perforatoraccording to Claim 1 wherein the discs are provided with cog wheels of greater diameter than the discs and act as bearing surfacesforthe discs to be located and rotated within the side frames.

5. A cross perforator according to Claim 4 wherein the discs are rotated by cog wheels mounted on a common shaft extending between the side frames,the cog wheels meshing with the cog wheels secured to the discs.

6. Across perforator according to Claim 1 wherein the driven means for the perforator cylinders is a gearwheel of a diameter proportional to the diameter ofthe perforator cylinder and so mounted in the discs that it will mesh with an input drive gear wheel common to all the perforatorcylindergear wheels carried by the discs.

7. A cross perforator according to Claim 1 wherein the means for locking the discs against rotation include a radial slot in each side frame and means which can open the slots to allowfreedom of rotation of the discs or closed to exert a nip and locking action on the discs positively to prevent rotation.

8. Across perforatoraccording to Claim 7 wherein the means to open and close the slot in each of the side frames includes a screw mechanism positively pulling or pushing the faces of each sot towards or away from each other.

9. A cross perforator according to Claim 3 wherein the plunger is withdrawn or released into a selected hole in the disc by means of a solenoid.

10. Across perforator according to Claim 5 wherein the discs are rotated by an electric motor.

11. A cross perforator according to Claim 7 wherein the means for opening and closing the radial slots is electro-mechanically operated.

12. A cross perforator according to Claim 1 wherein the selection of a specific perforator cylinder, the unlocking of the discs and their rotation for the selection and location of that specific perforator cylinder, and relocking the discs against rotation is effected electro-mechanically and automatically.

13. Across perforator selection system constructed and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.