GB2247205A

GB2247205A - Die cutting machine

Info

Publication number: GB2247205A
Application number: GB9018363A
Authority: GB
Inventors: Stephen Roy Baker
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-08-21
Filing date: 1990-08-21
Publication date: 1992-02-26
Anticipated expiration: 2010-08-21
Also published as: GB9018363D0; GB2247205B

Abstract

A die cutting machine is disclosed in which a die cutter 2, comprising a cutting rule 6 and a base board 4, is secured to a chase 30 by means of a frame 14. The frame 14 has opposed bevelled edges 24 received by fixed clamping means 26 and adjustable, clamping means 28 urged against the frame by springs 40. One frame may fit within another to accommodate a smaller die cutter. <IMAGE>

Description

DIE CUTTING MACHINES FIELD OF THE INVENTION This invention relates to die cutting machines.

BACKGROUND OF THE INVENTION In order to manufacture self-adhesive labels a web comprising a self-adhesive layer releasably adhered to a backing layer, is passed through a die cutter where a shape corresponding to the desired labels is repeatedly cut by a die at intervals along the web. The unwanted part of the self adhesive layer, ie the border around the labels, is usually pealed off. The labels may be printed or left plain (e.g. for address labels). As is known the cutter is in the form of a thin cutting rule which is inlaid in a base board.

The cutter extends right through the base board in which it is a friction fit. In use, the cutter is backed by a heavy metal chase against which one edge of the cutting rule bears. The other edge of the cutting rule is operative to cut the self-adhesive layer, but not the backing layer, against a platen.

One known way of securing the cutter to the chase, is to use double sided self adhesive tape. Since the cutting rule must bear directly on the chase, the tape has to be cut to shape so as to stick the base board to the chase but avoid the rule. To remove the cutter is difficult since it has to be prized off the chase, which is difficult to do without damaging the rule, and'the assembly often falls apart in the process. To remove one cutter and fit another using this system can take about an hour during which time the machine is not working.

Another known way of securing the cutter to the chase, is to make the base board of a standard size with opposed bevelled edges adapted to fit a clamping arrangement on the chase. Although,using this system, it takes only a few minutes to change cutters, the cutter manufacturers make a charge for producing the bevelled edges to fit the clamping arrangement, and the extra cost is a significant part of the total, which is would be desirable to avoid.

SUMMARY OF THE INVENTION In accordance with the invention, there is provided a die cutting machine in which a die cutter is secured to a chase by means of a frame. Cutters are made with a standard size base board, which may have plane (un-bevelled) edges. The cutter manufacturers do not currently charge extra for producing a base board of a particular size, merely for the special shaping to produce bevelled edges to fit the known clamping arrangements. To change a cutter the frame is unclamped, the cutter removed and a new one inserted, and the frame is replaced on the chase and re-clamped. Changing the cutter is simple and quick without the added expense of a specially shaped base board.

Preferably, the frame is rabbetted to receive the cutter.

In this form the edges of the base board are plane and unbevelled and dimensioned to fit the rabbetted frame.

Two opposed edges of the frame are preferably bevelled and engaged by correspondingly bevelled clamping members.

The invention also extends to a frame adapted to be clamped to the chase of a die cutting machine and to receive and retain a cutter.

The frame is preferably rabbetted to receive the cutter.

The invention further extends to a method of setting up a die cutting machine, comprising placing the base board of a die cutter in a frame, clamping the frame to the chase of the die cutting machine to secure the cutter on the chase, and securing the chase in the die cutting machine.

BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a section through a die cutter, chase and frame of a die cutting machine embodying the invention; Figure 1A shows an alternative construction, in section, of a detail of Figure 1; and Figure 2 is a plan view of the die cutter, chase and frame of Figure 1.

DETAILED DESCRIPTION Referring to the drawings, a die cutter 2 has a base board 4 and a cutting rule 6. The rule 6 is inlaid in the board, extending right through, as shown, so that the board is in two parts: and inner part 8 and an outer part 10 between which the rule 6 is held by friction.

The base board 2 is rectangular and has plane un-bevelled edges 12 on all four sides. That is to say the edges 12 include and angle of approximately 90 degrees with the face of the base board. The base board is so dimensioned as to fit snugly in a frame 14 which is rabbetted at 16 to provide a lip 18 all round to retain the base board. The rabbet may be machined, as illustrated in Figure 1, or may be provided by making the frame in parts 20 and 22 as illustrated in Figure 1A.

Two opposed edges 24 of the frame are bevelled at an angle to be received by opposed clamping members 26, 28 of a chase 30. The clamping member 26 is fixed on the base, whereas the member 28 is slidable, being attached by two screws 32 through elongate slots 34. Rods 36 projecting from the member 28 are slidably received in holes (not shown) in a base member 38 fixed on the chase 30, and locate compression springs 40 which urge the clamping member 28 against the frame 14. If the pressure of the springs 40 is insufficient to retain the cutter, the screws 32 may be tightened up. The frame is located transversely by a pin 42 which is fixed on the chase and engages in a corresponding notch in the frame.

In order to change a cutter, the screws 32 are loosened (if necessary), the member 28 is retracted to allow the frame to be removed, the cutter is removed from the frame, a new cutter is placed in the frame and the frame is reclamped on the chase.

In order to allow one cutter to be used on machines of different sizes, one or more frames may fit inside another.

While such an arrangement would not allow a cutter which is inherently large to be fitted on a machine which is too small, it does allow a small cutter to be fitted to both a small and a larger machine.

Claims

1. A die cutting machine in which a die cutter is secured to a chase by means of a frame.

2. A die cutting machine as claimed in claim 1, wherein the frame is rabbetted to receive the cutter.

3. A die cutting machine as claimed in claim 2, wherein the cutter has a base board the edges of which are plane and un-bevelled and dimensioned to fit the rabbetted frame.

4. A die cutting machine as claimed in any preceding claim, wherein the frame is clamped to the chase.

5. A die cutting machine as claimed in claim 4 wherein two opposed edges of the frame are bevelled and engaged by correspondingly bevelled clamping members.

6. A frame adapted to be clamped to the chase of a die cutting machine and to receive and retain a cutter.

7. A frame as claimed in claim 6, which is rabbetted to receive the cutter.

8. A frame as claimed in claim 7, wherein the rabbet is so formed as to receive a cutter base board the edges of which are plane and un-bevelled.

9. A frame as claimed in claim 6,7 or 8, adapted for engagement with clamping means of the chase of a die cutting machine.

10. A frame as claimed in claim 9, wherein two opposed edges of the frame are bevelled for engagement with the clamping means.

11. A method of setting up a die cutting machine, comprising placing the base board of a die cutter in a frame, clamping the frame to the chase of the die cutting machine to secure the cutter on the chase, and securing the chase in the die cutting machine.