GB2249744A - Sheet metal reforming tool - Google Patents

Abstract

The tool, for example in repairing distorted bodywork of a motor vehicle, comprises a jack post (10), carrying at one end a freely rotatable thrust foot (16) and provided with means (20) for rotating the jack post. The latter has a screw thread (12) on which is mounted a rider (24), to which any one of a number of differently-profiled thrust heads (34, 36, 44, 50) can be attached. Each thrust head has a thrust surface (38, 42, 48, 54) such that rotation of the jack post on the foot (16) moves the rider (24) along the post, to cause a force to be exerted by the thrust surface of the head on the structure to be reformed. <IMAGE>

Description

SHEET METAL REFORMING TOOL Thi invention relates to reforining tools for sheet metal structures, and in particular for correcting dents and other deformations in sheet metal bodywork, for example of an automotive vehicle, or a casing of an appliance such as a dom-estic washing machine.

According to the invention, a reforming tool for sheet metal structures comprises an externally-threaded jack post carrying at one end a thrust foot in which it is freely rotatable, the jack post being provided with means for rotating it with respect to the foot and the latter having a first thrust surface; a thrust head having a second thrust surface; and a rider having an internal screw thread mounted on the jack post and adapted to carry the thrust head so that when the foot and head are engaged against two generally-opposed surfaces of a sheet metal structure, rotation of the jack post causes the rider to move along the post to change the axial distance between the two thrust surfaces.

A reforming tool according to the invention will now be described, by way of example only with reference to the accompanying drawings, in which: Figure 1 shows the tool with an assortment of interchangeable thrust heads; Figures 2 and 3 show the tool set up ready for use in repairing a damaged boot structure of a motor car; Figure 4 shows it in use for repairing the front edge of a front panel assembly; Figure 5 shows the tool nuclullted for correcting deformation of a flitch-wing rail; Figure 6 shows the tool mounted for repairing a front wheel arch; Figure 7 shows two tools according to the invention mounted in a rear wheel arch;; Figure 8 shows the tool set up for clamping two structural elements together, using a thrust head in the form of a panel clamp; and Figure 9 is a plan view on the panel clamp, with respect to Figure 8.

Referring first to Figure 1, the reforming tool comprises a jack post 10 having an external screw thread 12 and carrying at its inner end 14 a conical thrust foot 16, which is mounted on the post 10 through a ball 18 on which it is freely rotatable. The ball 1.3 -5iows the foot 16 to swivel so that its flat end thrust face (not visible in the drawings), which defines the base of o h cone, can lie in any convenient plane not necessarily .-rtllogonal to the axis of the jack post 10. By virtue of the ball 18, the jack post is freely rotatable in th foot 16.

At the other end of the jack post 10, any convenient and suitable means is provided for engarting the jack post so as to rotate it with respect to the foot 16. In Figure 1, this consists of a nut 20 which is "'-ided to the post 10 and which has a spring-loaded ball 2.2 for locating a thrust head on the nut. A rider 24 consists of a block 26 having a through hole 28 which is threaded o cooperate with the post thread 12, so that the rider can ove along the post 10 when the latter is rotated and the rider restrained from rotating with it. These threads can le of any suitable configuration, e.g. square or truncated conical threads.

The block 26 has a radial extension 30, to engage snugly within the socket 32 of any one of a number of interchangeable thrust heads which provide the restraint against rotation of the rider 24.

Four such thrust heads are shown, by way of example only, in Figure 1. They comprise: a block cap 34 which consists of the socket 32 with a simple plate 38 closing one end; ~ a radial panel pusher 36, similar to the block cap 34 but having its end plate 40 extended so as to present a thrust surface 42 facing towards, and parallel to, the post 10; a wheel arch reformer 44 in which the plate 38 is replaced by a curved plate 46 having an external thrust surface 48 which may be cylindrical; and an axial panel pusher 50 in which the plate 38 is replaced by a plate 52 of L-shaped cross section, having opposed thrust surfaces 54 in planes parallel to the post 10.

In Figure 2, the post 10 is mounted with its foot 16 bearing against a wooden block 60 beeri ng against a cross member 62 of the vehicle, to take the reaction when the jack post 10 is rotated so as to incrcase the axial distance between the foot 16 and the rider 24, so that the latter, carrying in this case an axial panel pusher 50, is moved outwardly so as to eliminate a dent 64 in the bottom cill of the boot of the vehicle.

In Figure 3, the foot 16 is shown bearing directly on the cross member 62, and the rider 24 carries a radial panel pusher 36, for removing a dent 66 in L'he vertical edge of the boot opening.

In Figure 4, the tool is mounted within the bonnet aperture of the vehicle in a similar way to th.t shown in Figure 3 for using the panel pusher 36 to correct a dent 68 in the front panel of the vehicle.

Either the thrust head of the tool, or its thrust foot 16, may be applied to the deformed part of the structure.

Figure 5 shows an example of the latter situation, in which the jack post is mounted with its foot, not shown, bearing against a deformed area of the front wheel arch. The reaction is taken here by an axial panel pusher 50 bearing on the flitch-wing rail In Figure 6, a wheel arch reformer 44 is mounted on the rider 24, and is used to correct a dent 70 in the rim of a front wheel arch, with the foot 16 bearing on the inner longitudinal wall 72 of the flitch-chassis. Figure 6 also shows another example of a means for rotating the post 10, namely a socket attachment 72 carried on the opposite end of the post 10 from the foot 16.

In Figure 7, complex denting 74 in the part of the wheel arch that defines a rear door opening. can be corrected using more than one of the reforming tools according to the invention. These will typically he mouted in a similar way to Figure 6, using wheel arch reformers 44 (not shown in Figure 7) , and may be moved betwen various positions as required.

In the foregoing examples, the force. for correcting deformations in the structure under air are exerted with the jack post 10 in compression. Figure 8 s bows an example in which it acts as an element of a sl Amp, in cooperation with a thrust head (referred to as , > panel clamp) 76.The clamp 76 comprises a relatively 1 Is 78, for example of square section steel which may bc. bellow, hiving an end plate 80 fixed at one of its ends and projecting laterally from it The other end of the bar 7: carries the laterally projecting socket 32 into which the spigot 30 of the rider 24 fits. Figure 8 shows the tool mounted for clamping together two structural elements 82, so that they can for example then be welded together.

It will be appreciated that, whatever type of thrust head is used, the tool according to the invention is well adapted for use in confined areas, where other available equipment is restricted or unable to operate. The tool can easily and cheaply be manufactured from materials and components readily available in standard sizes.

The block cap 34, Figure 1, may for example be used for protecting the spigot 30 when a straight push is required, for example inside the chassis leg of certain types of car, or under the flitch and wing returns. Its external cross section need not be square as shown, but may be of any required profile, for example cylindrical or oval. The radial panel pusher 36 is particularly suitable for front panels and headlamp panels, since its front edge enables a controlled thrust to be exerted directly and accurately with minimal unwanted distortion to the panel as the latter is forced outwards.

Similarly, the wheel arch reformer Zi, suitably placed, enables a directional thrust to be exerted under accurate control, again with minimal unwanted panel distortion.

When a damaged wheel arch is under load from this component, the arch can be worked with hammers and conventional panel beating techniques to correct the contours. This can best be understood by reference to Figure 7, if the dents 74 project outl.#ardly.

It will also be appreciated that in mally cases two structural components can be brous together using thrust heads other than the clamp 76 of Figures 8 and 9: for example, in Figure 2 the damaged rear panel may consist of two welded panels, e.g. boot floor and rear panel, which have been forced apart and which will be brought together by the thrust exerted by the panel pusher 50.

Claims (10)

1. A reforming tool for sheet metal structures, comprising: - an externally-threaded jack post carrying at one end a thrust foot in which it is freely rotatable, the jack post having means for rotating it with respect to the foot, and the latter having a first thrust surface; - a thrust head having a second thrust surface; and - a rider having an internal screw thread, mounted on the jack post and adapted to carry the thrust head, so that when the foot and head are engaged against two generally-opposed surfaces of a sheet metal structure, rotation of the jack post causes the rider to move along the post to change the axial distance between the said first and second thrust surfaces.

2. A tool according to Claim 1, wherein the thrust head and the rider have respective co-operating mating elements for removably attaching the thrust head to the rider, with the mating elements extending transversely of the jack post.

3. A tool according to Claim 2 having a plurality of thrust heads, of different configurations each comprising at least one said second thrust surface on each head, so that the appropriate head can be selected for each operation of the tool.

4. A tool according to any one of Claims 1 to 3, having a thrust head in the form of a block cap with a simple flat second thrust surface in a plane generally parallel to the axis of the jack post.

5. A tool according to Claim 2 or Claim 3, having a thrust head in the form of a radial panel pusher which includes a transverse plate extended in the said plane so as to project from the mating element of the head in a direction parallel to the jack post axis and away from the thrust foot, the second thrust surface being defined on the projecting portion of the plate.

6. A tool according to any one of Claims 1 to 3, having a thrust head in the form of an axial panel pusher, in which two said second thrust surfaces are opposed to each other and lie in planes parallel to the jack post axis.

7. A tool according to Claim 2 or Claim 3, having a thrust head in the form of an arch reformer in which a curved plate is carried by the said mating element of the head and faces in a general direction away from the jack post, the second thrust surface being formed on the curved plate and being convex in the said general direction.

8. A tool according to Claim 2 or Claim 3, having a thrust head in the form of a panel clamp comprising the said mating element, an end plate extending generally parallel to the latter towards the jack post axis, and a rigid bar joining the mating element and end plate together, the second thrust surface being a surface of the end plate facing towards the mating element for supporting the thrust foot directly or indirectly.

9. A reforming tool for sheet metal structures, subsantially as described in the foregoing description with reference to Figures 1 to 7 of the accompanying drawings.

10. A tool according to Claim 9, further having a panel clamp substantially as described with reference to Figures 8 and 9 of the accompanying drawings.