GB2070491A

GB2070491A - Improvements in or relating to burning machines

Info

Publication number: GB2070491A
Application number: GB8106088A
Authority: GB
Original assignee: INTERCUT MACHINES Ltd
Current assignee: INTERCUT MACHINES Ltd
Priority date: 1980-03-01
Filing date: 1981-02-26
Publication date: 1981-09-09
Also published as: GB2070491B

Abstract

A workpiece supporting assembly for a burning machine comprises a support structure 18 and a grid-like burning platform 10 removably mounted on the support structure. The platform, carrying a cut workpiece, may be lifted off by e.g. a crane. Alternatively, the burning platform 10, together with the workpiece, is removed from the support structure 18 horizontally e.g. by wheels running on track 20 or by hydraulic rams; the first platform is then replaced by a second platform 24 on which a new workpiece has been loaded while the first platform was on the support structure. The arrangement permits substantially continuous use of the burning machine. <IMAGE>

Description

SPECIFICATION Improvements in or relating to burning machines The invention relates to burning machines, such as oxy-fuel, gas or plasma profile-cutting machines, of the kind comprising a grid-like burning platform mounted on a support structure.

When using conventional burning machines of this type, a great deal of time is normally spent in changing the workpiece, that is to say in removing cut parts, scrap and uncut plate, if any, and then replacing it with fresh plate. The delay comes not only in lifting off cut pieces one at a time but also in waiting for lifting equipment, cranes, forklift trucks etc., which may be engaged in other operations at a time when the machine has completed a burning operation and is ready for a change of workpiece. This has resulted in burning machines only actually operating for 30 to 40% of their time. The present invention provides a workpiece supporting assembly for a burning machine, and a method of using a burning machine, which will enable such delays to be avoided, thus permitting an increase in the output of a burning machine.

According to the invention a workpiece supporting assembly for a burning machine comprises a support structure and a grid-like burning platform mounted on the support structure, the burning platform being readily removable from the support structure and means being provided for facilitating said removal.

Since the burning platform may be removed from the support structure the workpiece may be loaded onto the platform, and removed from it after cutting, at a location away from the support structure, another previously loaded burning platform being fitted to the support structure and operated upon while such unloading and loading of the first burning platform is taking place.

Thus, the invention also provides a method of using a burning machine of the kind comprising a support structure and a grid-like burning platform removably mounted on the support structure, the method comprising removing the burning platform, together with the workpiece, from the support structure after the burning operation on the workpiece has been completed, replacing the first platform with a second burning platform on which a new workpiece has been loaded while the first said platform was on the support structure, replacing the workpiece on the first platform with a further workpiece while the burning operation on the workpiece on the second platform is being effected, and so on.

The burning platforms may be moved in succession between the support structure and a single loading/unloading location. Alternatively the burning platform may be moved in succession from the support structure to an unloading location, then from the unloading location to a loading location, and then from the loading location to the support structure.

In the workpiece supporting assembly according to the invention, the means for facilitating removal of the burning platform from the support structure may comprise a plurality of lugs, for attachment of crane slings, spaced apart along the side edges of the platform. Alternatively or additionally, there may be provided wheels on the platform cooperating with a first track fixed in relation to the support structure, whereby the platform may be removed from the support structure by displacing it along said first track.

In this case there may be provided a second track having portions extending transversely of said first track from both sides thereof, whereby a burning platform carrying a cut workpiece may be removed from the support structure along the first track and one portion of the second track, and a burning platform carrying a new workpiece may be moved onto the support structure along the other portion of the second track and the first track.

Alternatively, the second track may extend away from the support structure on a side thereof other than the side from which the first track extends, whereby a burning platform carrying a cut workpiece may be removed from the support structure along the first track and a burning platform carrying a new workpiece may be moved onto the support structure along the second track.

In this case the first track may join the second track at a combined loading/unloading location where a cut workpiece may be removed from a burning platform and replaced by a new workpiece.

In any of the above arrangements the burning platform preferably comprises a substantially rectangular frame and a plurality of spaced parallel support bars mounted across the frame. A metal mesh or grid may be disposed below the support bars to catch small cut items or scrap from the workpiece.

The burning platform may be formed in two or more sections independently removable from the support structure.

The workpiece supporting assembly may incorporate a water table, that is to say the burning platform may extend across at least part of an open-topped container for water, means being provided for varying the relative level of the platform and the surface of the water within the container. Besides collecting the slag and swarf produced in the burning operation, the use of the water table also reduces the incidence of fumes, dust and workpiece distortion.

The support structure for the burning platform may be adjustable vertically to vary the level of the platform with respect to the surface of water within the container. Suitable workpiece supporting assemblies for this purpose are described and claimed in co-pending Patent Application No.

The following is a more detailed description of various embodiments of the invention reference being made to the accompanying drawings in which: Figure 1 is a plan view of a burning platform, Figure 2 is a side elevation of the burning platform shown in Figure 1, Figure 3 is a part section along the line 3-3 of Figure 1, Figure 4 is a diagrammatic plan view of an assembly incorporating the burning platform of Figures 1 to 3, and Figures 5 and 6 are diagrammatic side elevations of the burning platform when being carried by a crane.

Referring to Figures 1 to 3, the burning platform 10 comprises a rectangular frame 1 1 the side components of the frame 11 being T-shaped in cross-section as best seen in Figure 3. The leg 12 of the T-section projects horizontally inwards and supports beams 13 around the four sides of the frame.

The notched ends of cross bars 14 are supported on the beams 13. The bars 14, which are usually spaced apart by about 150 to 200 mm, tend to get nicked and damaged during burning operations. They may therefore be individually replaceable or they may be fixed bars with copper or similar capping, as indicated at 15, to prevent damage.

Mounted on the frame 1 1 beneath the bars 14 is a metal grid or mesh 1 6, the size of the mesh being sufficiently small to prevent small cut parts falling through the platform. Thus the size of the mesh may be approximately 50 mm.

Lifting lugs 17 are spaced at intervals along each side of the burning platform for attachment of crane slings for lifting and transporting the platform. The platform can be in one piece as shown, or it may be arranged so that it is in two or more sections which may be lifted off together or as individual sections.

The burning platform may be removably supported on any suitable supporting structure.

For example, it may be used with a water table, as previously mentioned, or it can also be used on "dry beds" i.e. with standard cutting machines, oxy-gas or plasma, where no water table is being used.

After the burning operation on the workpiece carried by the platform has been completed, the platform is removed from the supporting structure and a second platform, which has already been preloaded with a further workpiece, is then placed on the supporting structure. While the burning machine is cutting the workpiece on the second platform the first platform may be unloaded at leisure and reloaded, at another location if required, ready for the next change.

The removal of the burning platform from the supporting structure may be effected simply by lifting the burning platform from the structure using a crane. However, Figure 4 shows an arrangement for efficiently handling the burning platforms.

In the arrangement shown in Figure 4, the supporting structure for the burning platform, whether a water table or dry bed, is indicated diagrammatically at 18 and the burning equipment, incorporating a burning head which may be moved along the burning platform, is indicated diagrammatically at 19. Operation of the burning apparatus may be automatically controlled in known manner.

The burning platform 10 is carried by wheels which may be caster wheels, or of a ball type capable of moving in any direction, or may be steerable wheels. The wheels cooperate with a first track 20 which leads laterally from the support structure 1 8. Fixed motors under the track, driving pinions or sprockets meshing with a rack (not shown) fixed to the underside of the burning platform 10, move the platform along the track 20 when required. Alternatively the movement of the platform along the track 20 may be effected by any suitable electrical, mechanical or hydraulic means; for example, the platform may be moved from the support structure by hydraulic rams.

When displaced along the track 20 from the supporting structure 18, the burning platform passes on to a second track 21 extending transversely of the track 20 and having portions 22 and 23 on opposite sides of the track 20.

When the burning platform 10 has been moved onto the track 21 it is moved longitudinally of the track by any of the means referred to above in relation to movement along the track 20. The end portion 22 of the track 21 constitutes an unloading position and the end portion 23 constitutes a loading position.

The assembly shown in Figure 4 operates as follows: While the first burning platform 10 is on the support structure 18 and the workpiece thereon is being cut by the burning machine, a second platform 24 in the loading position 23 is being loaded with a new workpiece. When the burning operation has been completed, the platform 10 is displaced along the track 20 from the support structure onto the track 21, and is then displaced into the unloading position 22. The preloaded platform 24 may then be advanced along the track 21 and then displaced along the track 20 into the cutting area where it is supported on the supporting structure so that burning can continue with the minimum of delay.

While the burning platform 10 is in the unloading position, as indicated at 1 Oa, the workpiece is removed at leisure, the cut parts going to a cut parts store and the scrap also being removed. When emptied the platform is returned along the track 21 to the loading position 23 where it is preloaded with a fresh workpiece.

When the burning operation of the workpiece on the second platform 24 has been completed, the process is repeated, the platform 24 being moved to the unloading position and the platform 10, reloaded, being returned to the burning position. It will be appreciated that the method of operation could be modified so that either the position 22 or the position 23 constituted both the loading and unloading position, the other position being merely a temporary siding for locating the used burning platform while the freshly loaded platform is being moved to the cutting area.

Instead of burning platforms being both moved out of and into the cutting area along the track 20, there may be provided a further track leading, at right angles to the track 20, from the support structure 18 to a further location 26, shown dotted, which is in turn connected to the location 23 by a further track 27. It will be appreciated that with this arrangement the location 22 may be dispensed with and the burning platforms may be moved in succession from the cutting area to the locations 26, 23 and 21, or in the reverse direction. In this case loading and unloading may be effected in any of the three locations away from the cutting area.

Where comparatively small workpieces are being cut on a comparatively large burning platform it makes for easy operation if the workpieces are located adjacent the front edge of the platform. However, this moves the centre of gravity of the loaded platform towards that end and preferably, therefore, a plurality of the aforementioned lifting lugs 17 are provided along each side of the burning platform so that the lifting slings of a crane may be connected to the appropriate lugs to minimise tilting of the loaded platform.

Thus Figure 5 shows diagrammatically the arrangement in the case where a workpiece, indicated diagrammatically at 27, is loaded evenly over the burning platform. In this case the crane slings 28 are connected symmetrically to lugs 1 7 adjacent opposite ends of the platform 10.

In the arrangement of Figure 6, on the other hand, the workpiece 27 is disposed adjacent one end of the platform and the slings 28 are therefore connected between end lugs 17 and central lugs 17 on the burning platform 10 so as to bring the centre of gravity of the loaded platform as nearly as possible beneath the suspension point of the slings to prevent tilting of the platform which could, in a severe case, lead to dangerous displacement or dropping of the load.

Claims

1. A workpiece supporting assembly for a burning machine comprising a support structure and a grid-like burning platform mounted on the support structure, the burning platform being readily removable from the support structure and means being provided for facilitating said removal.

2. A workpiece supporting assembly according to claim 1, wherein said means for facilitating removal of the burning platform from the support structure comprise a plurality of lugs, for attachment of crane slings, spaced apart along the side edges of the platform.

3. A workpiece supporting assembly according to claim 1 or claim 2, wherein said means for facilitating removal of the burning platform from the support structure comprise wheels on the platform cooperating with a first track fixed in relation to the support structure, whereby the platform may be removed from the support structure by displacing it along said first track.

4. A workpiece supporting assembly according to claim 3, wherein there is provided a second track having portions extending transversely to said first track from both sides thereof, whereby a burning platform carrying a cut workpiece may be removed from the support structure along the first track and one portion of the second track, and a burning platform carrying a new workpiece may be moved onto the support structure along the other portion of the second track and the first track.

5. A workpiece supporting assembly according to claim 3, wherein there is provided a second track extending away from the support structure on a side thereof other than the side from which the first track extends, whereby a burning platform carrying a cut workpiece may be removed from the support structure along the first track and a burning platform carrying a new workpiece may be moved onto the support structure along the second track.

6. A workpiece supporting assembly according to claim 5, wherein the first track joins the second track at a loading/unloading location where the cut workpiece may be removed from a burning platform and replaced by a new workpiece.

7. A workpiece supporting assembly according to any of the preceding claims, wherein the burning platform comprises a substantially rectangular frame and a plurality of spaced parallel support bars mounted across the frame.

8. A workpiece supporting assembly according to claim 7, wherein a metal mesh or grid is disposed below the support bars.

9. A workpiece supporting assembly according to any of the preceding claims, wherein the burning platform is formed in two or more sections independently removable from the support structure.

10. A workpiece supporting assembly according to any of the preceding claims, wherein the burning platform extends across at least pert of an open-topped container for water, means being provided for varying the relative levels of the platform and the surface of water within the container.

11. A workpiece supporting assembly according to claim 10, wherein the support structure for the burning platform is adjustable vertically to vary the level of the platform with respect to the surface of water within the container.

1 2. A workpiece supporting assembly substantially as hereinbefore described with reference to the accompanying drawings.

13. A method of using a burning machine of the kind comprising a support structure and a grid-like burning platform removably mounted on the support structure, the method comprising removing the burning platform, together with the workpiece, from the support structure after the burning operation on the workpiece has been completed, replacing the first platform with a second burning platform on which a new workpiece has been loaded while the first said platform was on the support structure, replacing the workpiece on the first platform with a further workpiece while the burning operation on the workpiece on the second platform is being effected, and so on.

14. A method according to claim 13, wherein burning platforms are moved in succession between the support structure and a single loading/unloading location.

15. A method according to claim 13, wherein burning platforms are moved in succession from the support structure to an unloading location, then from the unloading location to a loading location, and then from the loading location to the support structure.