GB2258263A

GB2258263A - Hook for a vehicle spare wheel cradle.

Info

Publication number: GB2258263A
Application number: GB9116611A
Authority: GB
Inventors: David Parke
Original assignee: Metallifacture Ltd
Current assignee: Metallifacture Ltd
Priority date: 1991-08-01
Filing date: 1991-08-01
Publication date: 1993-02-03
Anticipated expiration: 2011-08-01
Also published as: GB9116611D0; GB2258263B

Abstract

A hook member (11) for a vehicle spare wheel carrier is made from a length of metal tube swaged and internally tapped at one end (20) and flattened and punched at the opposite end to form the hook (25). The tapped end (20) screws onto a threaded stem (12) which is attached to the vehicle. The stem is rotated to cause raising and lowering of the hook and the cradle which it engages. <IMAGE>

Description

HOOK MEMBER FOR VEHICLE SPARE WHEEL CARRIER AND METHOD OF MANUFACTURE This invention relates to a hook member for a vehicle spare wheel carrier and to a method of manufacture of the hook member.

It is well known to mount a spare wheel in a motor vehicle in a position slung beneath a floor of the vehicle.

A carrier for securing the wheel in position usually comprises a screw-threaded stem extending through the vehicle floor with a head accessible within the vehicle for permitting rotation of the stem. A hook member screw engages with the stem externally of the vehicle and engages with a cage, which holds the spare wheel. The head of the stem can be rotated in one direction to draw up the hook member to secure the spare wheel, or in the reverse direction to release the spare wheel.

One form of hook member, no longer used, comprised a metal forging and a metal tube. The forging defined the hook-shaped part and was drilled to provide a bore to receive the stem. The bore was additionally drilled out to produce a counterbore to receive the tube, so that the bore formed a continuation of the tube bore. The forging and tube were then welded together and the opposite end of the tube was tapped with an internal screw thread for engaging with the stem.

This produced a strong, but very expensive hook member and alternative cheaper constructions have been produced.

One such example is disclosed in GB-A-2204843. This construction uses metal pressings for securing a nut and for defining the hook portion. A disadvantage of this construction is that it is possible for the hook portion to be forceably bent to release the spare wheel.

Another example is disclosed in GB-B-2108565. This provides an effective construction, in which the tube and hook portion are formed in one piece from a flat metal blank. The hook portion comprises two opposite portions of the blank, which are welded together after forming to produce a strong hook portion. At the opposite end, a nut is welded in the tube. It would be advantageous to simplify this construction and reduce the member of operations in manufacture.

A further example is disclosed in EP-A-0431738. In this construction, the hook member is again formed from a flat blank, but the nut is secured by captivation during the forming operation.

The present invention is concerned with further simplifying the construction of such a hook member, whilst maintaining the desired strength to prevent forcing open of the hook portion.

The present invention provides a hook member for a vehicle spare wheel carrier having an elongate hollow body with a hook portion at one end, the body having an internal screw thread for screw engagement with a rotatable stem for use in moving the hook member between securing and releasing positions, the body comprising a tube provided with the screw thread at the end remote from the hook portion, wherein the hook portion is defined by a flattened end part of the tube with a portion removed to define the hook formation.

Reference is now made to the accompanying drawing, wherein figure 1 is a side elevation of a spare wheel carrier, with a hook member according to the invention; and figure 2 is a view of a part of the hook member shown in figure 1, in the direction of arrow "A".

The spare wheel carrier shown comprises a hook member 11, screw-mounted on a stem 12, dependent, in use, from a casing 10, secured to a vehicle floor (not shown). The hook is movable along the stem from the securing position shown, to a release position and serves to support a pivoted cage (not shown) for a spare wheel, as described in GB-A-2108565. Movement is effected by turning the stem 12, while the hook member 11 is prevented from rotation by its engagement with the cage. The stem has a non-circular, eg hexagonal, head 13 to facilitate turning of the stem from within the vehicle.

The casing 10 has a circular depression 14 defining a cup-like portion 15 having a frusto-conical aperture 16.

A frusto-conical bearing 17 seats in and closes the aperture and, itself, has a bore through which the stem extends. The head 13 seats in the depression 14 on the bearing 17. The stem 12 has an external screw thread 18 and the end portion 19, remote from the head 13, is deformed to prevent removal of the stem from the hook member 11.

The hook member 11 is made from a length of metal tube. One end part of the tube is swaged to define a reduced cross-section end part 20 and this end part is tapped to form an internal screw thread 21. This internal screw thread is complementary to and engages with the thread on the stem 12.

The opposite end part of the tube is flattened to define a dove-tail shaped end part 23 as viewed in one elevation (as in Figure 1). In the perpendicular elevation, as shown in Figure 2, the end part 23 has a tapering shape, reducing in depth from the main body of the tube to the end of the dove-tail shaped part.

After the flattening operation, and at the same work station, a punching operation is carried out to remove a piece of the dove-tail to define a slot 24. The slot extends through both opposite sides of the dove-tail shaped end part 23 and defines a hook-shaped portion 25.

The hook member is, therefore, produced from a cheap length of tube, which is easily formed to define both the hook and the threaded part. The resultant hook member is made in one piece, so that there is no risk of welded parts coming apart. The hook member is strong and not capable of being bent to release the spare wheel, as is possible with a hook formed from sheet metal.

The arrangement with a reduced diameter end part 20, to define the screw threaded portion, permits tapping of only the end part of the tube and ensures that the stem is loosely received in the tube adjacent the formed hook member, so that formation of the hook portion does not interfere with movement of the hook member on the stem.

Claims

1. A hook member for a vehicle spare wheel carrier having an elongate hollow body with a hook portion at one end, the body having an internal screw thread for screw engagement with a rotatable stem for use in moving the hook member between securing and releasing positions, the body comprising a tube provided with the screw thread at the end remote from the hook portion, wherein the hook portion is defined by a flattened end part of the tube with a portion removed to define the hook formation.

2. A hook member according to claim 1, wherein the flattened part converges from adjacent the tubular body part to the end of the hook portion, as viewed perpendicularly to the flattened sides of the flattened part.

3. A hook member according to claim 1 or 2, wherein the screw thread is tapped into the body of the hook portion.

4. A hook member according to claim 3, wherein the end part of the tube remote from the hook portion is reduced in diameter and the reduced diameter portion is tapped with the screw thread.

5. A hook member substantially as herein described with reference to the accompanying drawings.

6. A method of making a hook member for a vehicle spare wheel carrier, of the type having an elongate hollow body with a hook portion at one end, the body having an internal screw thread for screw engagement with a rotatable stem for use in moving the hook member between securing and releasing positions, the method comprising providing a tube and providing one end part of the tube with the internal screw thread, wherein the end part of the tube opposite to the screw-threaded part is relatively flattened and the flattened part is subjected to a cutting operation to remove a portion of the flattened part to define the hook formation.

7. A method according to claim 6, wherein the flattened part converges from adjacent the tubular body part to the end of the hook portion, as viewed perpendicularly to the flattened sides of the flattened part.

8. A method according to claim 6 or 7, wherein the screw thread is tapped into the body of the hook portion.

9. A method according to claim 8, wherein the end part of the tube remote from the hook portion is reduced in diameter and the reduced diameter portion is tapped with the screw thread.

10. A method according to claim 6, substantially as herein described.