GB1601468A

GB1601468A - Method and jig for making a box

Info

Publication number: GB1601468A
Application number: GB30071/77A
Authority: GB
Original assignee: Chloride Group Ltd
Current assignee: Chloride Group Ltd
Priority date: 1978-05-31
Filing date: 1978-05-31
Publication date: 1981-10-28

Description

(54) METHOD AND JIG FOR MAKING A BOX (71) We, CHLORIDE GROUP LI MITED, a Company registered under the Laws of England, of 52, Grosvenor Gardens, London SW1W OAU, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement.

This invention relates to a method and a jig for making a box from two part boxes, for example a rectangular box which is long compared with its cross sectional dimensions as would be suitable for a cell box for an electric traction, or other storage battery.

The box is conveniently of a thermo-plastics material.

According to one aspect of the present invention, in a method of making a box, two part boxes are located, each in one part of a jig, each of which jig parts locates both an inside surface and an outside surface of its part box, the jig parts are brought together so that the edges of the respective part boxes abut one another, and the edges are welded together while so located.

Preferably, the welding is by a hot plate welding method according to which the edges to be welded together are heated by contact with a hot plate before they are finally brought together, the hot plate is removed and the edges are then brought together while still hot and become welded.

In the past it has been found difficult to locate edges of part boxes precisely, particularly where a box has had at least one long dimension in the area of the weld, but the method of locating each part box in its jig part on both its inside and outside surfaces overcomes that difficulty.

According to a second aspect of the invention, a jig for making a box from two part boxes comprising two jig parts, each part consisting of relatively movable inner and outer clamping members for locating each part box on both an inside and an outside surface thereof, and guides ensuring that when the two jig parts are brought together the spaces in the respective jig parts between the inner and outer clamping members are in alignment.

In some applications it will be convenient to have two outer members, one hinged from an inner member on each side.

Both members may be rebated at the side where the exposed edges of the part boxes will be, so that there is a precisely defined space at the weld where a controlled amount of flash can be formed. By defining precisely the position of'any flash, it becomes a fairly simple matter to remove it after welding. If only the outer members are rebated, then the flash will appear at the outside of the finished box, whence it is easily removed.

The jig is preferably associated with a welding hot-plate adapted to be inserted between the jig parts and withdrawn again before the jig parts are finally brought together to complete the weld.

The guide means conveniently comprises dowels, and there may be separate dowels for the inner members and for the outer pieces of the corresponding jig parts.

Also preferably there are clamp means both for holding the outer parts in relation to the cores, and for holding the two jig parts together during welding.

The invention may be carried into practice in various ways, and one embodiment and a modification will be described by way of example, with reference to the accompanying drawings; of which: Figure 1 is a perspective view of a jig with two half boxes located in the two jig parts before the jig parts are brought together; Figure 2 is an exploded view of the lower jig part in Figure 1; Figure 3 is a cross-section through the upper jig part in Figure 1; Figure 4 is a view corresponding to Figure 3 of two jig parts which have been partly moved together ready for heating by a welding hot-plate but have not finally been brought together for welding; each jig part is similar to that of Figure 3 although somewhat modified; Figure 5 ids a sketch of a modified form of the one jig part, Figure 6 is a sectional end elevation of the jig part of Figure 5 with the half box clamped in position on the plane VI-VI in Figure 5; and Figure 7 is a side view of the jig part of Figure 6 as seen from the direction of the arrow VII.

The jig is for forming boxes of thermoplastics material, for example heat-weldable polyprorylene, polyethylene, or structural foam polystyrene, or ABS, or SAN, which boxes are more-or-less square in cross section, but have a length equal to several times that of the cross sectional dimensions A box is formed from two identical half boxes shown at 11 and 12, the split between the half boxes being in a symmetrical plane parallel with the longest dimension of the box.

Each half box is first clamped in one of two identical jig parts 13, and each jig part comprises a core 14 and outer pieces 15 and 16, which are pivoted or hinged at 17 on either side of the core 14 at one end.

A half box 12 can be fitted over the core 14 and then the outer parts 15 and 16 can be closed on either side of the half box, and clamped by a clamp acting in the direction of the arrows 20 in Figure 3.

A series of brackets 18 are secured to the upper sides of the jig outers for locating the half box in a direction parallel with the hinge axes.

It will be seen from Figure 3 that on both the inside and the outside of the half box wall, adjacent the exposed edge 19, the box is securely located between the core 14 and one of the outer pieces 15 and 16.

Then the two jig parts are brought together by movement guided by dowels 21.

Shortly before the edges 19 of the two half boxes come together, a heated welding plate is inserted long-wise between them to heat the edges in preparation for welding. Then the jig parts are slightly separated, the welding plate is withdrawn, and the jig parts are finally brought together with the cooperating edges 19 of the two half boxes in precisely aligned contact with each other by movement defined by the dowels 21, and in that condition they become welded together. There may be a clamp acting to hold them together.

Both the core 14 and the outer pieces 15 and 16 are rebated at 22, at either side of the half box edge to be welded, to leave a space for the formation of flash, which can subsequently be removed.

After welding, the outer pieces 15 and 16 can be pivoted about their hinges 17, so that the brackets 18 dear the sides of the half boxes, and the outer pieces clear the welded box as shown in Figure 2, so that the box can be withdrawn longitudinally from the core 14 and the flash can be removed.

Figure 4 shows a modification with an additional dowel 25 for guiding the respective core parts 26 which in that modification are large enough to locate on all three inside surfaces of a half box. Also instead of having the brackets 18, the outer pieces 27 have internally extending flanges 28 for locating the surfaces of the half boxes at the outside of the corners.

In the modification shown in Figures 5, 6, and 7, the movable clamp parts are on the inside rather than on the outside of each jig part.

Thus a half box 31 is clamped on its three long outer surfaces between two side plates 32 and a back plate 33, which is in fact adjustable in position between the side plates 32 and can be exchanged with a back plate 33 of a different width, so that the components can be easily adapted for clamping half boxes af different sizes.

The half box 31 consisting of three long sides, and one end is fitted into the parts 32 and 33, and clamped on the inside by a pair of elongate clamping bars 34, each of which extends along the inner side of one long edge of the half box 31.

The clamping action is by operation of toggle arms 35 by elongate movement of a rod 36 by an actuator, the rod being positioned in bearings in an elongate channel member 37 supported in the box on feet 38.

As shown best in Figure 7, in the particular form being described, each elongate bar 34 is in two parts, end to end, and each is acted on by a pair of toggle arms 35, so that there are eight toggle arms in all in four pairs, and they are all operated by the common rod 36.

The jig parts are mounted from a machine support 39 to be capable of guided movement towards each other along guide rods 41, so that the two half boxes come thegether with the edges in alignment with each other.

An end plate 43 moves about a pivot 44 against the ends of the half boxes and the jig parts, to ensure correct alignment.

Welding is performed as described with reference to Figures 1-3 by inserting a heated welding plate between the two jig parts just before the edges come together to heat the edges, and then the plate is removed, the edges are brought together and held together until they are welded.

Finally, the inner clamp 34 is released by operation of the rod 36, and the back plate 43 is pivotted downwards so that the welded battery box can be withdrawn longitudinally in the direction of the arrow 46 in Figure 5.

There may be some freedom of movement of the side plates 32, away from the back plate 33, and movement of the back plate 33 away from the box to make withdrawal quite easy.

There may be flash rebates, as indicated at 22 in Figure 3, on either of the clamp members 32, and 34, but preferably they are only in the side plates 32 at the welding edge, and the arrangement is such that all the flash will appear at the outside because it is much easier to remove external flash after the box has been withdrawn from the jig, than it is to remove flash on the inside.

Although the specific embodiment describes the jig parts in use with half boxes, it will be appreciated that the invention is applicable to the production of boxes in which the parts are of other proportions besides half to half.

WHAT WE CLAIM IS: 1. A method of making a box in which two part boxes are located, each in one part of a jig each of which jig parts locates both an inside surface and an outside surface of its part box, the jig parts are brought together so that the edges of the respective part boxes abut one another, and the edges are welded together while so located.

2. A method as claimed in Claim 1 in which the edges to be welded together are heated by contact with a hot plate before they are finally brought together, the hot plate is removed, and the edges are then brought together while still hot and become welded.

3. The method as claimed in Claim 1 or Claim 2 in which the jig parts are removed after the edges have been welded together.

4. A method of making a box performed substantially as herein specifically described with reference to Figures 1 to 3, or 4, or 5 to 7 of the accompanying drawings.

5. A jig for making a box from two part boxes comprising two jig parts, each part consisting of relatively movable inner and outer clamping members for locating each part box on both an inside and an outside surface thereof. and guides ensuring that when the two jig parts are brought together the spaces in the respective jig parts between the inner and outer clamping members are in alignment.

6. A jig as claimed in Claim 5 in which each jig part comprises outer clamping members and respective opposed inner clamping members capable of being expanded by a toggle mechanism towards the outer members.

7. A jig as claimed in Claim 5 in which each jig part comprises a core and at least one outer clamping member hinged to the core.

8. A jig as claimed in any of Claims 5 to 7 in which one or each clamping member of each jig part is rebated at the side where the exposed edges of the part boxes will be.

9. A jig as claimed in Claim 8 in which it is only the outer clamping members that are rebated.

10. A jig as claimed in any of Claims 5 to 9 in which a welding hot plate is adapted to be inserted between the jig parts, and withdrawn again before the jig parts are finally brought together.

11. A jig as claimed in any of Claims 5 to 10 in which the guides comprise dowels on which the corresponding jig parts can be moved.

12. A jig as claimed in any of Claims 4 to 11 in which the two part boxes are open-ended to allow the inner clamping members to be removed.

13. A jig constructed and arranged substantially as herein specifically described with reference to Figures 1 to 3 or Figure 4, or Figures 5 to 7 of the accompanying drawings.

14. A box comprising two part boxes welded together along their corresponding edges by a method as claimed in any of Claims 1 to 4 or by use of a jig as claimed in any of Claims 5 to 12.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. operation of the rod 36, and the back plate 43 is pivotted downwards so that the welded battery box can be withdrawn longitudinally in the direction of the arrow 46 in Figure 5. There may be some freedom of movement of the side plates 32, away from the back plate 33, and movement of the back plate 33 away from the box to make withdrawal quite easy. There may be flash rebates, as indicated at 22 in Figure 3, on either of the clamp members 32, and 34, but preferably they are only in the side plates 32 at the welding edge, and the arrangement is such that all the flash will appear at the outside because it is much easier to remove external flash after the box has been withdrawn from the jig, than it is to remove flash on the inside. Although the specific embodiment describes the jig parts in use with half boxes, it will be appreciated that the invention is applicable to the production of boxes in which the parts are of other proportions besides half to half. WHAT WE CLAIM IS:

1. A method of making a box in which two part boxes are located, each in one part of a jig each of which jig parts locates both an inside surface and an outside surface of its part box, the jig parts are brought together so that the edges of the respective part boxes abut one another, and the edges are welded together while so located.