GB2589285A

GB2589285A - Cutting devices

Info

Publication number: GB2589285A
Application number: GB1905864.3A
Authority: GB
Inventors: Davis Matthew
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-04-26
Filing date: 2019-04-26
Publication date: 2021-06-02
Also published as: GB201905864D0

Abstract

A cutting device 100 that has a planar support 102 having an edge 114 and a blade 106 arranged to move relative to the edge which is moved by an actuator 137 so as to slice the workpiece substantially perpendicularly to the planar support. At least a portion of the edge adjacent the blade is non-straight. The blade has a side surface terminating in a cutting edge facing towards the support. The shape of the side surface of the blade, when viewed perpendicular to the plane of the support, corresponds to the non-straight edge portion. The device may have fence 104 against which an edge of a workpiece 110 can be placed when lying on the planar support. The blade may have curved 120 and straight 116 portions, which cut a pattern into an edge of the workpiece adjacent the fence. Indicia 142 are provided to ensure that subsequent cuts are aligned with previous ones such that by indexing the workpiece along the fence relative to the indicia, a continuous scalloped pattern can be formed along the edge of the workpiece. The invention simplifies the process of cutting a pattern into lead or aluminium roof flashing.

Description

CUTTING DEVICES

This invention relates to cutting devices, and in particular, but without limitation, to guillotine-type cutting devices suitable for shaping an edge of lead or aluminium flashing.

Flashing is used in the building industry, for example, to render weathertight a junction between a wall and another component, such as a roof, window frame, etc. The flashing is designed to shed rainwater away from the junction and onto an underlying structure, such as a roof, so that the actual wall-roof intersection does not need to be made 100% watertight.

Flashing is typically installed by raking out the mortar between adjacent bricks, and feeding-in an edge of the flashing strip into the space between the bricks. Mortar and/or sealant can be injected into the gap to form a seal between the inserted flashing material and the existing brickwork. The flashing can then be bent by hand, or hammered into shape, so that it folds downwardly then away from the wall, to overlie the underlying structure. This is shown, schematically, in Figure 1 of the accompanying drawings.

In Figure 1, a known roof-wall intersection 10 is shown in which a lean-to roof 12 meets a wall 14. The wall 14 is made from courses of bricks 16 with layers of mortar 18 between the bricks 16. Rainwater 20 falling onto the front surface 22 of the wall 14 could run down in the small gap 24 between the roof 12 and the wall 14. Flashing 26 is therefore installed to shed 28 the rainwater off the wall 14 and onto the upper surface 30 of the roof 12 away from the gap 24.

The flashing 26 is installed by raking out the mortar 18 between two courses of bricks 16 to form a small gap 32 into which an upper edge 34 of the flashing 26 can be inserted. Grout or a sealant 34 can be injected into the gap 32 to form a seal between the upper edge 34 of the flashing 26 and the course of bricks 16 above it. Once installed, the flashing 26 can be bent/hammered down 36 until it meets the roof 12, before being moulded 38 outwardly from the wall to follow the contour of the roof 12. This causes rainwater 20 hitting the wall 14 to run down the wall and to be shed onto the upper surface 30 of the roof 12, rather than running down into the building through the small gap 24 between the roof 12 and the wall 14. In many cases, the free edge 40 of the flashing 26 is straight, and this can be acceptable. However, in certain situations, the free edge 40 needs to be profiled so as to have a shape that matches pre-existing flashing elsewhere on the building. Examples of scalloped flashing are well known to those skilled in the art.

As shown in Figure 2 of the drawings, when forming a shaped or scalloped edge 40 on the flashing 26, it is customary for the installer to use a template 40 to mark out 42 the shape that is desired, e.g. using a marker pen 44, and to use tin snips, or other cutting devices (not shown) to cut 46 along the pre-marked line 42 to form the convoluted or scalloped free edge 40.

This marking-out and hand-cutting process is a very fiddly and time-consuming and also risks injuring the installer due to the presence of sharp edges and the use of cutting tools.

In fact, the time taken to cut-out the scalloped edge 40 of the flashing 26 is generally considerably greater that the amount of time it takes to actually install the flashing 26, once cut to shape.

A need therefore exists for an improved method of forming a shaped, convoluted or scalloped edge on a sheet metal material, and in particular, a method and/or apparatus which is suitable for forming a shaped, convoluted or scalloped edge on flashing material, such as sheet lead, tin and aluminium.

This invention aims to provide a solution to one or more of the above problems, and/or to provide an improved and/or alternative method for cutting sheet materials to a desired shape/profile.

Aspects of the invention are set forth in the appended independent claim or claims. Preferred and/or optional features are set forth in the appended dependent claims.

According to a first aspect of the invention, there is provided a cutting device comprising a generally planar support having an edge, a blade arranged to move relative to the edge, and an actuator for moving the blade relative to the edge. The invention is characterised by the edge of the generally planar support having at least a portion or part thereof, which is non-straight, and by the blade having a side surface, which terminates in a cutting edge facing towards the generally planar support, which, when viewed perpendicular to a planar support, corresponds to the non-straight portion of the edge of the support.

By moving the blade past the edge of the support, with a substrate placed on the support, it is possible to use the cutting edge of the blade to cut through the substrate. Because the edge of the generally planar support has a non-straight edge, and because the shape of the blade corresponds thereto, by cutting the substrate thus, a non-straight profile is cut out of the substrate. The shape of the non-straight portion of the edge of the planar support thus defines the shape formed by the edge of the substrate. The non-straight portion can have any desired shape, such as comprising a combination of straight edges and curved portions.

It will be appreciated, by the skilled reader, that the invention enables the somewhat fiddly marking and hand-cutting process described with reference to Figure 2 above, to be carried out in a more straightforward and convenient manner.

Suitably, the side surface of the blade slides adjacent to the non-straight portion of the edge of the support when moved relative thereto. Suitably, a clearance of less than lmm is provided between the side surface of the blade and the non-straight portion of the edge of the support.

Generally speaking, the smaller the clearance between the blade surface and the non-straight portion of the edge, the greater the accuracy of the cut so formed will be. However, with relatively thick substrates, it is sometimes desirable to provide a clearance between the side surface of the blade and the edge of the support so as to avoid jamming of the blade by cut material. In certain embodiments of the invention, the side surface of the blade is arranged to slide against, i.e. contact, the non-straight portion of the edge of the support. This configuration may be particularly beneficial for thin substrate cutting operations.

In certain embodiments of the invention, the clearance between the side surface of the blade and the non-straight portion of the edge of the support may be adjustable. This could be accomplished, for example, by mounting the blade on a lead screw, or lead screws, which can be rotated to offset the blade relative to the non-straight portion of the edge of the support.

The blade comprises a cutting edge, which faces generally towards the planar support. The cutting edge is preferably sharpened and suitably comprises a chamfer, which faces away from the non-straight portion of the support. By arranging the chamfer thus, as the blade cuts through the substrate, the off-cut material is pushed away from the support. Typically, the off-cut material is the waste material, and so by pushing the waste material away from the retained (useful) part of the substrate, this avoids inadvertently damaging or bending the retained part of the substrate/workpiece.

In order to improve the precision of the cut, the non-straight portion of the support may be chamfered away from the cutting edge of the blade. Typically, the generally planar support will have a flat upper surface, terminating in the non-straight edge portion. The chamfer will thus undercut the non-straight portion of the free edge such that the upper surface of the support remains flat.

When two chamfers are used in combination, namely a chamfer on the blade and a chamfer on the non-straight portion of the edge, a more accurate cut can be produced in certain circumstances. Preferably, the cutting edge is inclined so that it acts to shear the substrate, rather than operating as a "punch" type device. This can be accomplished by forming the cutting edge at an incline when viewed parallel to the plane of the support. Thus, when the blade is moved towards the substrate to be cut, the blade contacts the substrate first to one side of the non-straight portion, and the intersection between the blade edge and the edge of the non-straight portion of the support moves along the non-straight portion of the edge as the blade is advanced. This progressively cuts-out the profile as the blade is moved relative to the edge, rather than attempting to cut the entire profile all at once. By cutting the profile progressively, the amount of effort required is reduced, and/or the accuracy of the cut can be improved. This configuration may also lead to reduced bending of the workpiece edge during the cutting operation, which is also advantageous.

In a preferred embodiment of the invention, the generally planar support is substantially flat.

Suitably, the edge of the planar support comprises straight portions located on one, or opposite sides, of the non-straight portion. A fence may also be provided against which, in use, an edge of the substrate to be cut can be positioned so as to align the substrate accurately and/or reproducibly with the non-straight portion of the edge of the support. By placing the work piece against the fence, a first cut can be made using the device, and the work piece indexed/advanced to a second position so that a further cutting operation can be carried out. By careful alignment of the workpiece before each cut, which can be assisted by using suitable guide/alignment indicia, an elongate strip of substrate can be cut incrementally by indexing it against the fence between each successive cutting operation.

In order to improve the versatility of the cutting device, the non-straight portion of the edge of the support and the blade are suitably interchangeable. This can be accomplished in a variety of 10 ways.

With regard to the blade, this can be detachably affixable to the actuator, for example using a bayonet-type connection, bolts and nuts, a clip fitting etc. With regard to the interchangeable non-straight portion of the edge of the support, this can be rendered interchangeable by providing a recess or cut-out in the support surface itself, into which an insert can be placed. The insert has a shaped free edge, which, when inserted into the recess/cut-out, forms the non-straight portion of the edge of the support. The insert can be retained in-situ using a magnet, screws, bolts and nuts, a clip formation, etc. Suitably, blade/insert pairs are provided as a set and can be interchanged when they wear out, for servicing/maintenance purposes, and/or when the user desires to change the shape of the cut formed by the device.

The shape of the non-straight portion can take any desired form, for example, a set of straight edges inclined relative to one another, a curved portion or a combination of straight and curved portions.

The actuator suitably comprises a guide means that constrains the movement of the blade so that its side surface moves substantially perpendicular to the non-straight edge portion of the support.

This can be accomplished in a variety of ways, amongst which are providing one or more linear guides to which the blade is slideably affixed and a mechanism, which, when actuated, moves the blade towards the support surface whilst being constrained by the linear guide or guides. A cam can be provided, which when rotated, causes the blade to move towards the support surface. Additionally, or alternatively, a lever may be provided which moves the blade towards the support surface A return spring or counterweight may be provided to return the blade to a position where it is moved away from the support surface. This can be particularly, beneficial when carrying out multiple cutting operations as the blade will move clear of the support surface enabling the substrate/work piece to be moved freely beneath the blade, or between the blade and support. In one embodiment of the invention, the actuator is controlled using a handle, which is connected to a lever, which forces the blade towards the support. In other embodiments of the invention, a mechanically-assisted actuator may be provided. A mechanically-assisted or mechanical actuator may take the form of an electric motor, an electric telescopic actuator, a hydraulic ram, a pneumatic piston, etc., which moves the blade towards and/or away from the support on demand. A safety interlock is suitably provided to prevent/inhibit the movement of the blade when the device is not in use. This can take various forms, such as an electronic safety system, or in a simple embodiment, a locking pin or catch, which locks the actuator in either an open or closed position.

An embodiment of the invention shall now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic cross-section of a known flashing installation; Figure 2 is a schematic perspective view of a known flashing cutting operation; Figure 3 is a perspective view of an embodiment of a cutting device in accordance with the invention; Figure 4 is a close-up view of the cutting device shown in Figure 3; Figure 5 is a perspective view of the cutting device of Figure 3 with the blade in elevated position; and Figure 6 is a schematic front view of the cutting device of Figure 3 showing the inclination of the cutting edge of the blade.

Referring to Figures 3 to 6 of the drawings, a cutting device 100 in accordance with the invention comprises a generally planar support surface 102 having a fence 104 along one edge thereof. A material to be cut (not shown for clarity) can be placed on the support surface 102 with its edge to be cut placed against the fence 104. This would be done with the blade 106 of the cutting device 100 in an elevated position, as shown in Figures 5 and 6 of the drawings.

The support surface 102 is generally flat, but has a recess 108 in its upper surface, which receives a profiled insert 110. The profiled insert 110 is held in position by a set of removable screws 112, and so the insert 110 is interchangeable. The insert 110 has a free edge 114, which is non-straight. In the illustrated embodiment, it has a "scalloped" profile, that is to say a straight edge portion 116 leading away from the generally straight edge 118 of the support adjacent the fence 104, a curved portion 120, and a second straight portion 122 leading back into the straight edge 118 of the edge of the support adjacent the fence 104. The blade 106 has a side surface 124, whose shape corresponds to the edge 114 of the insert 110. The blade 106 can thus be moved up or down (in the drawings) and pass by the non-straight free edge 114 of the support/insert 110.

In the illustrated embodiment, the insert 110 is formed from plate steel, as is the blade 106.

As can be seen, in particular, from Figure 6 of the drawings, the blade 106 has a cutting edge 126, which is inclined relative to the support 102. In Figure 6 of the drawings, it can be seen that the cutting edge 126 is lower on the left-hand side of the blade 106 compared with the right-hand side of the blade 106. Thus, as the blade 106 is moved downwardly, the left-hand edge thereof contacts the work piece (not shown) before the right-hand side thereof This results in a slicing action, as opposed to a punching action, which would be the case if the cutting edge 126 were parallel with the support surface 102.

The blade 106 is constrained to move linearly by virtue of a slide rail 130, which locates within a guide rail 132. The guide rail is perpendicular to the plane of the support 102, and so the blade 106 is constrained to move perpendicular to the plane of the support 102.

The blade 106 is welded to a set of cross pieces 134, which are in turn welded to the sliders 130. The entire blade assembly, that is the blade 106, the cross pieces 134 and the sliders 130 can be removed from the cutting device 110 by sliding it out of the guide rails 132 vertically.

At least one of the cross members 134 has an extension part 136, which detachably connects to a lever 137. The detachable connection is formed by way of a bolt and nut 138, which can be connected to the lever 137 at one of several different positions 139, which give rise to different mechanical advantages. By moving the lever 137, the upright 136 is pushed by the lever, which causes the blade 106 to move towards, away from, the support 102.

As can be most clearly seen in Figures 3 and 4 of the drawings, a return spring 140 is provided, which returns the blade 106 to an elevated position after each cutting operation.

It can also be seen, in particular, in Figures 4 and 5 of the drawings, that the support surface 102 is provided with alignment indicia 142 to assist in indexing the work piece (not shown) along the fence 104 so that each successive cut using the device 100 correctly lines-up with a cut previously made by the device 100.

Finally, as shown in Figure 6 of the drawings, a locking device 158, 160 is shown, which, in the illustrated embodiment, comprised a screw-in pin 158 that engages with an aperture 160 in the slider 130. When the blade has been brought down, the pin 158 aligns with the aperture 160 and can be inserted therein to lock the device in a safe, closed position. Other configurations are equally envisaged, such as a spring-loaded pin, an aperture arranged to lock the device in an open position, and so on.

Although the invention has been described with reference to a manual embodiment using a lever, it will be readily apparent to the skilled reader that the lever/handle 150 mechanism described herein above could be replaced by an electric, pneumatic or hydraulic system. However, the device 100 as shown in the accompanying drawings has the benefit of being robust, simple, lightweight and easily transportable.

The invention is not restricted to the details of the foregoing embodiments, which are merely exemplary of an embodiment of the invention. The scope of the invention is set forth in the appended claims.

Claims

CLAIMS1. A cutting device comprising a generally planar support having an edge, a blade arranged to move relative to the edge, and an actuator for moving the blade relative to the edge, wherein: at least a portion of the edge which is adjacent the blade is a non-straight; the blade has a side surface terminating in a cutting edge facing towards the generally planar support; and wherein the side surface of the blade, when viewed perpendicular to a plane of the support, corresponds to the non-straight portion of the edge of the support.
2. The cutting device of claim 1, wherein the side surface of the blade slides adjacent to the non-straight portion of the edge of the support when moved relative thereto with a clearance of less than lmm therebetween.
3. The cutting device of claim 1 or claim 2, wherein the side surface of the blade slides against the non-straight portion of the edge of the support when moved relative thereto.
4. The cutting device of any preceding claim, wherein the cutting edge of the blade is chamfered away from the non-straight portion of the support.
S. The cutting device of any preceding claim, wherein non-straight portion of the support is chamfered away from the cutting edge of the blade.
6. The cutting device of any preceding claim, wherein the cutting edge is inclined, when viewed parallel to a plane of the support, such that upon movement of the blade relative to the support, an intersection of the cutting edge and the non-straight portion of the edge of the support moves along the cutting edge of the blade.
7. The cutting device of any preceding claim 1, wherein the generally planar support is substantially flat.
8. The cutting device of any preceding claim, wherein the edge of the planar support comprises straight portions located on one, or opposite, sides of the non-straight portion.
9. The cutting device of any preceding claim, wherein the support comprises a fence against which, in use, an edge of a substrate to be cut, can be positioned to align the substrate with the non-straight portion of the edge of the support.
10. The cutting device of any preceding claim, wherein the non-straight portion of the edge of the support and the blade, is interchangeable.
11. The cutting device of claim 10, wherein the support comprises a recess in an surface thereof for receiving an insert, the insert comprising a shaped free edge which, when the insert is present, forms the non-straight portion of the edge of the support.
12. The cutting device of any preceding claim, wherein the non-straight portion comprises a plurality of straight edge portions arranged at angles to one another.
13. The cutting device of any preceding claim, wherein the non-straight portion comprises a curved portion.
14. The cutting device of any preceding claim, wherein the non-straight portion comprises a curved portion and at least one straight portion.
15. The cutting device of any preceding claim, wherein the actuator comprises a guide means that constrains the movement of the blade so that its side surface moves substantially perpendicular to the non-straight edge portion of the support.
16. The cutting device of claim 15, wherein the guide means comprises one or more linear guides to which the blade is slideably affixed, and a cam, which when rotated, moves the blade towards the support surface against the action of a return spring or counterweight.
17. The cutting device of claim 15, wherein the guide means comprises one or more linear guides to which the blade is slideably affixed, and a lever, which when pivoted about its fulcrum, moves the blade towards the support surface against the action of a return spring or counterweight.
18. The cutting device of claim 16 of claim 17, further comprising a handle for actuating the cam or lever.
19. The cutting device of claim 16 of claim 17, further comprising a mechanical actuator for actuating the cam or lever.
20. The cutting device of claim 19, wherein the mechanical actuator comprises any one or more of: a linear actuator; a pneumatic cylinder; a hydraulic ram; an electric motor; a solenoid; and an electric telescopic actuator.
21. The cutting device of any preceding claim, further comprising a safety lock for selectively inhibiting or permitting the movement of the blade relative to the edge.