GB2128983A - Cutting sheet material e.g. glass - Google Patents

Abstract

A device for cutting large sheets of glass etc. is used in a vertical position so that it uses little table space and comprises two boards 1, 2 hinged together and arranged so that they are co-planar to define a bed for cutting the glass G. One board 2 can be moved relative to the other 1 by releasing a catch 6, so causing a score mark in the glass to propagate to crack the glass into two pieces. The score may be made through slot 5 in heavy metal guide 4. <IMAGE>

Description

SPECIFICATION Cutting of sheets The invention relates to the cutting of sheets of glass, card, board, paper and the like. The invention is seen to good advantage in relation to the cutting of glass into panels e.g. for framed pictures and for convenience (but not for limitation) the invention will be described with reference to that specific use.

Glass sheets or panels are cut by scoring or marking a surface of the sheet and then applying pressure to one side of the sheet along the score line to make a complete break or cut. It is necessary to rest the sheet on a flat bed for a proper cut and break to be made and working space is required not only to make the cut but also to move the sheet so that the breaking can be done. The breaking action is done by hand and requires a measure of care and often some degree of skill. Space can be a problem, especially in the workshop of an art gallery or for the handy an and this problem is aggravated where large glass, say 180cm x 120cm are involved.

It is one object of the invention to provide an improved bed for the cutting of glass, etc. which is easy and reliable to use and which occupies less space in storage and use.

According to one aspect of the invention there is provided a device for use in cutting a sheet of glass, card, paper or the like placed thereon, the device comprising a bed formed of two generally flat board portions one of which is movable relative to the other about a straight joint line, into and out of a position coplanar with the other board portion, and means to support the bed with the board portions when co-planar in a substantially vertical plane and the joint line in a non-horizontal plane.

Most preferably the moving means comprises a hinge joining the boards together in side-by-side relation and arranged so that one board portion may pivot away from and below the other a distance sufficient to allow for the score mark to propagate across the thickness of the sheet of glass and cause the separation.

Most preferably the bed includes a guide to be placed on the sheet and arranged to present a guiding edge for the operator using a scoring or marking device and to present a weight to increase the engagement of the sheet on the fixed board portion, so to counteract the force applied to lower the movable board portion.

It is a feature of the invention that the bed be used vertically, i.e. supported or mounted on a wall or standing on a table. Because walls are high one can easily accommodate sheets of large size and because the bed can be made of low thickness - the minimum thickness is that required to allow for the relative movement of the movable portion - little space is occupied. According to a much preferred feature therefore, the bed includes fixing means by which it may be used vertically and the means preferably comprises a frame to be secured to a wall or which is self-standing. Preferably, the frame is dimensioned so that the boards measure 150 cm x 200 cm. Preferably the bed is mounted on the wall or in the frame so that it is at an angle, better to rest the sheet on the bed.

In order that the invention may be well understood it will now be described by way of example with reference to the accompanying diagrammatic drawings in which: Figure 1 is a plan view of a cutting bed; Figure 2 is a side elevation of the bed of Figure 1; and Figure 3 is a transverse section through the bed in use and taken along lines Ill-Ill on Figure 1.

The bed comprises two boards 1, 2, made of wood, plastics or metal, the boards being hinged together along their longer sides by end hinges 3, Figure 3, only one of which is shown. The top end of a heavy metal guide 4 is pivotally secured to a wall support W, Figure 2, so that it may be lifted up and down with respect to the joint line of the two boards.

The guide 4 is marked with a scale, not shown. The guide 4 has a longitudinal enclosed slot 5 which, as can be seen in Figure 1, exposes the joint line to view. Guide 4 is made in two halves which are joined by hinges across the top and bottom of the slot 5, which allows the right hand side of the guide to follow movement of the board 2. The slot 5 is dimensioned to receive the blade of a cutting tool, e.g. a glass cutting wheel, not shown. At one side of the board 2 there is a wall mounted releasable catch 6, adapted to hold the board 2 in line with the board 1 which is fixed to the wall W by a frame member 7.

A ledge 8 having a scale is present along the lower ends of the boards 1 and 2, to receive the sheet to be cut. Latch 9 to engage the lower end of the guide 4 is mounted on the ledge 8. As shown in Figure 2, the bed is inclined slightly to the vertical. The boards may measure 150 cm high and be about 200 cm in total width.

In use, the catch 6 is arranged so that the board 2 is in line with the board 1 to present a flat bed or surface area. The guide 4 is lifted and a pane of glass G, Figure 3, is placed on the boards, with the intended fracture line overlying the joint line of the boards. The guide 4 is then lowered and the latch 9 may be used to secure the lower end of the guide 4 in place. The operator then passes the wheel of a glass cutter, not shown, along the slot 5, to score the glass, the line being guided by the wall of the slot 5.

Hand pressure is then applied to the right hand side of the guide 4 at the same time as the catch 6 is released so allowing the board 2 to fall relative to the board 1 an angular distance determined by the hinges 3. The sudden lack of support on part of the pane of glass G caused by the fall of the board 2 causes the score line on the glass pane G to crack the glass into two pieces. The weight and location of the guide 4 ensures that the second piece does not fall with the board 2, and that there is enough engagement of the pane and the underlying board 1. In this way the glass pane G is cut in a simple and clean way, and the device occupies little floor or table space. The device may be used to cut sheet materials other than glass e.g. card, board or paper.

The device may be mounted in a frame box not shown, and the guide 4 may be arranged to move along a track.

Claims (12)

1. A device for use in cutting a sheet of glass or the like, comprising a bed formed of two generally flat board portions one of which is movable relative to the other about a straight line, into and out of a position co-planar with the other board portion, and means to support the bed with the board portions when co-planar in a substantially vertical plane and the joint line in a non-horizontal plane.

2. A device as claimed in Claim 1, in which the board portions are connected together by a hinge.

3. A device as claimed in Claim 1 or Claim 2, including a guide adapted to be positioned on a sheet on the bed to serve as a guide for a tool used to score the sheet.

4. A device as claimed in Claim 1,2, or 3, in which the support means comprises a frame adapted to be secured to a wall.

5. A device as claimed in Claim 1,2, or 3, in which the support means to support the bed comprises a self standing frame.

6. A device according to any preceding Claim, in which the support means is dimensioned so that it projects away from its supporting wall just the distance required for the relative movement of the movable board.

7. A device as claimed in Claim 4, 5, or 6, in which the bed is mounted in the frame so that the bed is at an angle to the vertical.

8. A device as claimed in any preceding Claim, including a catch to secure the board portions in their co-planar relationship and arranged so that release of the catch causes one board to move with respect to the other.

9. A device as claimed in Claim 8 as dependent on Claim 3, in which the catch also serves to secure the guide in its guiding position.

10. A device as claimed in Claim 3, in which the guide is dimensioned and of such a weight that the cut off piece of sheet does not follow the movable board portion when it moves out of the co-planar position with the other board portion.

11. A device as claimed in any preceding Claim, in which the boards measure about 150 cm x 200 cm.

12. A device for use in cutting a sheet of glass, substantially as described with reference to the drawings.