Swaging Tools

Abstract

A swaging tool, for assembling hose to couplings, which permits a limited range of hose sizes to be swaged with one tool, while avoiding the undesirable formation of lobes, which lead to leaks. The tool has a plurality of outer dies arranged around one axis, the outer dies moving in a radial direction on opening and closing of the tool. Positioned between the outer dies are insert which also move in a radial direction on opening and closing of the tool. Both the dies are in contact with the hose assembly when the tool is closed, of which the following is a specification.

Description

This invention relates to swaging tools, particularly to swaging tools such as are used for assembling hose to couplings and similar items.

It is desirable that the swaging should extend for as much of the periphery of the coupling as possible. Also it is desirable that the swaging should be circular without the formation of lobes. This is particularly the case for couplings for high pressure hose, to provide effective sealing against leaks.

Effective swaging can be obtained if dies are made and used for only one specific size. However, if any attempt is made to use the dies for a size slightly larger than the specific size, the final shape is not circular. For example, if four dies are used, sliding radially, then as the size actually being swaged increases above the designed or specific size the swaged form tends to form four lobes, giving a somewhat square shape, in cross-section.

The present invention provides an arrangement of dies which will permit a limited range of size swaged for any particular set of dies. In accordance with the present invention there is provided a plurality of outer dies around an axis, each die movable relative to and in unison with the other dies, in a radial or generally radial direction, and a number of insert dies positioned between at least some of the outer dies, the insert dies movable relative and in unison with the outer dies also in a radial or generally radial direction. The outer dies and insert dies are movable from an open position, wherein gaps exist between adjacent outer dies and between insert and outer dies, to an extreme position wherein the outer dies and insert dies are all in close or substantially close contact.

In a particular example a swaging tool comprises four dies. The tool is arranged to open on a diametric center line, to admit an assembly for swaging. For convenience parts will be referred to as upper and lower with the opening line extending horizontally, although it will be appreciated that other arrangements can readily be provided. Thus the tool has an upper part which comprises a central die normally fixedly attached to a main tool body in turn connected or attached to the ram of a press.

In addition to the central die, the upper part of the tool also has two further upper side die portions, one of each side of the central die and the side dies have limited sideways movement relative to the central die. Additionally the side dies are connected to the main tool body for movement therewith. By this arrangement, the central die moves vertically in relation to the coupling being swaged, this movement also being radial. The side dies move vertically and also horizontally inwards towards the coupling and the final movement is thus radial, or generally so.

Situated between each side die and the central die is an insert die. Each insert die is located, relative to the outer or side and central dies either side, so that it also has a generally radial movement. Conveniently compression springs are positioned between each insert and the associated outer dies to tend to move them apart. Compression springs may also be positioned between the central die and the side dies.

A similar arrangement of central die, inserts and lower portions of said side dies forms the lower part of the tool. It will be seen that the tool therefore has four outer dies, and four insert dies, for the particular arrangement described. On opening and closing of the tool, the outer dies and insert dies move away from each other and towards each other.

The number of outer dies can vary as can also the number of insert dies, although it has been found that tools with four outer dies and four insert dies provide a suitable arrangement for swaging in the range of three-sixteenths inch to 2 inches. Larger dimensions can be swaged but an increase in the number of dies may be useful for much larger sizes.

A particular embodiment with four outer dies and four insert dies will now be described in detail, by way of example in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a tool for mounting in a press the tool being in an open position and viewed in a direction along an axis which would be the axis of coupling positioned in the tool for swaging, with a cover plate removed for clarity;

FIG. 2 is a view similar to that of FIG. 1 but with the tool in a closed position, and

FIG. 3 is a side elevation of a press incorporating the tool shown in FIGS. 1 and 2.

The tool comprises upper and lower parts indicated at 10 and 11 respectively. The upper part 10 comprises a central die 12, and upper portions 13 of the two side dies. Between each side die 13 and the central die 12 is an insert die 14. The central die is attached to a tool body which in turn is attached to the ram of a press (see FIG. 3). A cover plate 15 (FIG. 3) is attached to the central die 12 by a screw 16 and dowels 17. The cover plate extends over the central die 12, the side dies 13 and the insert dies 14. The side dies are movably attached to the cover plate 15 by screws 18 passing through appropriate slots in the cover plate. Compression springs 20 are positioned between each insert and the die on each side and also between each die. The springs are housed in holes drilled or otherwise formed in the dies and insert dies.

The lower part 11, of the tool, is similar to the upper part and comprises central die 22, lower portions 23 of the two side dies, and insert dies 24. The central die 22 is attached to a part of the press and usually is stationary. A cover plate 25 is attached to the central die 22 by a screw 26 and the dowels 27. The side dies 23 are movably attached to the cover plate 25 by screws 28 passing through slots in the cover plate and each side die portion 23 of the lower part 11 is attached by means of a dowel 31 to a corresponding side die portion 13 of the upper part 10. Compression springs 30 are positioned between inserts 24 and dies 22 and 23, and between the dies.

As seen in FIG. 3, the upper central die 12 is attached to a side plate 35 by means of a screw 36, the side plate in turn attached to an upper tool body 37 by screws 38. The tool body 37 is attached to the ram of a press (not shown). In addition to being attached to the side plate 35, the upper portions 13 of the side dies, are positioned in a recess (not shown) inside the upper tool body 37.

Similarly, the lower central die 22 is attached to a side plate 40 by a screw 41, the side plate in turn attached to a lower tool body 42 by screws 43. The lower tool body 42 is attached to the bed of a press (not shown). The lower central die 22, and the lower side die 23, are positioned in a reces (not shown) inside the lower tool body 42.

Grease nipples 44 are provided in the side plates 35 and 40 to enable grease to be forced between the dies and the surfaces of the recesses in the tool bodies to reduce friction.

In operation the tool is opened by the upper part 10 of the tool being lifted by the press ram and upper tool body 37. The central die 12 moves upward, carrying with it the cover plate 15. The cover plate 15 lifts the side dies 13 but these dies are also moved sideways by the action of the springs 20. Also the insert dies 14 are moved to intermediate positions between the central die 12 and the side dies 13. The springs 20 and 30 thus act as means to circumferentially locate the insert dies.

When the upper part 10 is lifted the side dies 23, of the lower part of the tool, move upwards and outwards. The central die 22 does not move but insert dies 24 move to positions intermediate the central die 22 and side dies 23 by camming against sholder 48. Dowels 31 extend between the side dies 13 of the upper part and the side dies 23 of the lower part. Both cover plates 15 and 25 have a semi-circular recess to allow for the insertion of a coupling.

A coupling and the hose is positioned between the tool parts and then the press is operated to close the tool. As the tool closes, the various dies move towards each other with the inserts being supported by shoulders of each of the recesses and by the springs 20,30, and at the same time the coupling will be pushed down on to the central die 22.

For a specific size coupling, the outer dies and insert dies are designed and made to close completely. However, it is possible to swage a coupling which is slightly bigger than the specific size for which the tool is designed. This is because the dies and inserts are spaced around the coupling and the extra circumferential dimension is divided into a number of gaps between the various dies and inserts. Thus the amount of out-of-roundness produced on an oversize coupling is quite small. Normally the size of the coupling is very important and very little oversize can be allowed for acceptable swaging. With the present invention oversize of 0.1 inch can readily be accommodated and larger oversizes can often be accommodated. Some limitation to the oversize is set by the maximum gap which can be permitted between outer dies and insert dies. Generally this gap -- in the closed condition -- should not exceed 11/2 times the thickness of the wall of the sleeve of the coupling which is to be swaged.

Although described, and illustrated, as being mounted for vertical movement of the tool, it can also be mounted for horizontal movement. Also both parts of the tool can be movable, if desired.

Claims

Having now described my invention, what I claim is:

1. A swaging tool comprising a plurality of outer dies arranged around an axis, each outer die movable relative to and in unison with the other outer dies in a radial or a substantially radial direction with respect to said axis, a number of insert dies positioned between at least some of the adjacent pairs of outer dies, each of said insert dies being positioned in recesses formed in each of the dies of an adjacent pair of outer dies, means to circumferentially locate each insert die relative to the recesses of an adjacent pair of outer dies and each insert die being supportable by a shoulder formed by the recess in each of the outer dies of an adjacent pair of outer dies so as to be movable relative to and in unison with the outer dies in a radial or a substantially radial direction with respect to said axis.

2. The swaging tool of claim 1, the tool having at least four outer dies and an insert die between each pair of adjacent outer dies, said tool composed of two parts separated by a diametrical axis.

3. The swaging tool of claim 2, comprising four outer dies, two of said outer dies being side dies, each side die being composed of two side die portions separated on said diametrical axis; each part comprising a central outer die; a side die portion positioned on each side of the central outer die; and an insert die positioned between each side die portion and the central outer die.

4. The swaging tool of claim 1 in which the means to circumferentially locate the insert dies is compression springs housed in recesses formed in the outer dies and insert dies.

5. A swaging tool as claimed in claim 2 including a cover plate for each part of the tool, the cover plate fixedly attached to the center die, and means slidingly attaching the side dies to the cover plates, to permit the radial movement thereof.

6. A swaging tool as claimed in claim 2, the diametrical axis extending horizontally, and each part of the tool having an external shape to fit in a corresponding recess in a tool body of a press.