GB2078639A - Spoked wheels - Google Patents

Abstract

A wire wheel for motor vehicles or motor cycles comprises a central hub portion (2) connected to a separate wheel rim (1) by means of a plurality of spokes (3) each secured to the wheel rim by means of a nipple (8) screwed onto the end of the spoke and having an enlarged head portion (10) which seats on the radially outer surface of the rim, e.g. in a dimple (15), the nipple head (10) being shaped to receive a tool by means of which it can be rotated to tension the spoke from outside the rim. The nipple head may be externally shaped, e.g. with splines, to receive a suitable tool or it may have an internal bore shaped to receive a key. <IMAGE>

Description

SPECIFICATION Improvements in or relating to wire wheels and method of assembly thereof The invention relates to wire wheels and more particularly to wire wheels for motor vehicles and motor cycles, the invention also relates to a method of assembling wire wheels.

Wire wheels essentially comprise a hub portion which is separate from the rim on which the tyre is mounted, the hub portion being connected to the rim by means of a number of regularly spaced wire spokes. One end of each spoke is usually swaged over to provide an enlargement by means of which it may be anchored in a hole in the hub portion.

The other end of the spoke is threaded along part of its length and this threaded portion passes through a hole in the wheel rim, the spoke being tensioned between the rim and the hub portion by means of an internally threaded nipple mounted on the threaded portion of the spoke. The nipple has an enlarged head which locates in a dimple around the hole in the wheel rim. The body portion of the nipple protrudes through the hole in the rim to the exterior thereof and has an external shape which is either hexagonal or square or alternatively some other shape which can cooperate with a spanner by means of which the nipple can be tightened.

To assemble a wire wheel of the above described type, the spokes are inserted through the hub portion and loosely retained therein by means of their swaged over heads. The threaded end of each spoke is guided through the dimpled hole in the wheel rim and a nipple is screwed onto the spoke from the inside of the rim until it is finger tight. The same procedure is repeated for all the spokes and thereafter, they have to be tensioned to a predetermined load which must be evenly spread around the wheel. This is done by using a spanner on the appropriately shaped body portion of the nipple protruding from the wheel rim.

One of the problems with such a method of assembly is that the nipples are often damaged during the tightening process and this can detract from the overall appearance of the wheel particularly, as is usually the case, when all the parts of the wheel, especially the spokes, have been nickel plated because the damaged area allows rust to set in very quickly and the wheel becomes badly discoioured.

It is therefore an object of the invention to provide a wire wheel in which the spokes may be tensioned from within the rim so that if the nipples are damaged during the tightening process, such damage and any later rusting resulting therefrom will be hidden from view within the tyre when it is fitted to the wheel rim.

According to one aspect of the invention there is provided a wire wheel comprising a hub portion connected by a plurality of spokes to a separate rim on which a tyre may be mounted, each spoke being located in a hole in said rim by means of a nipple threadingly mounted thereon and having a head portion which seats against the rim around said hole, tightening means on or in the nipple head portion located inside the rim shaped to be drivingly engaged and rotated by a tightening tool only from within the rim to tension the spoke.

In a preferred embodiment, the head of each nipple is provided around all or part of its periphery with a plurality of splines but the external shape of the head of each nipple may be square or hexagonal to co-operate with a correspondingly shaped tightening tool.

According to another aspect of the invention there is provided a method of assemblying a wire wheel comprising a hub portion connected by means of a plurality of spokes to a separate wheel rim, each spoke being located in a hole in the wheel rim by means of a nipple, the method comprising tensioning the spokes from within the rim to their final required predetermined loading using a tightening tool which drivingly engages a shaped part on or in a head portion of the nipple.

Preferably the nipple head is engaged by a tightening tool which co-operates with an externally shaped part on the nipple head but the nipple head could be provided with a specially shaped internal bore to receive a correspondingly shaped tool such as an Allen key.

The invention further provides a tightening tool for use in the above described method comprising a body portion having one end shaped to cooperate with the correspondingly shaped part of the nipple head, the tool having an opposite end provided with means whereby the tool may be rotated to tighten the nipple when it is engaged therewith. Conveniently, said one end of the tool 3 internally splined to co-operate with corresponding splines on a nipple head.

Alternatively said one end of the key may be internally square or hexagonal in cross-section to co-operate with a correspondingly shaped nipple head.

A preferred method of assembling wire wheels and a wire assembled in accordance therewith will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a front view of a wheel of the invention, Figure 2 is an end view of the wheel of Figure 1, Figure 3 is an enlarged view of the mounting of one of the spokes shown in Figure 1, Figure 4 is a side view, partly in cross-section, of the nipple shown in Figure 3, and Figure 5 is a cross-section through a key for tightening the nipple of Figures 3 and 4.

Referring to the drawings, there is shown in Figure 1 a wheel of the invention which comprises a central hub portion connected by a plurality of short spokes 3 and longer spokes 4 to a separate wheel rim 1. The inner end of each spoke has an enlarged swaged terminal portion 5 by means of which the spoke is retained in a hole 6 in the hub portion 2 (see Figure 3).

The wheel rim is formed with a plurality of spaced holes 7 (see Figure 3) to receive the other end of each spoke 3, 4, the portion of the rim surrounding each hole being deformed to provide a recess or dimple 1 5 therein, the shape of the dimple being such that it is angled to provide an end face 1 6 containing the hole 7 which is at right angles to the spoke it is to receive.

The end of each spoke located in the rim hole 7 is threaded to receive thereon a nipple 8 by means of which the spoke can be secured to the wheel rim and tensioned in relation thereto in the manner to be described hereafter. Each nipple 8 has an internally threaded through-bore 9 (see Figure 4) to enable it to be screwed onto the spoke end. In the illustrated preferred nipple, the bore 9 extends right through the nipple but this is not essential as it could stop short of nipple head 10 if desired. The illustrated nipple head 10 is circular when viewed from above and is provided around its periphery with splines so that it can be rotated by a similarly splined key 11 such as that shown in Figure 5. Preferably the nipple head 10 is shaped as illustrated but it will be appreciated that it could be square or hexagonal or any other suitable shape if desired.

In another embodiment (not shown) the upper part of the bore 9 can be shaped to receive an Allen key, the internal threading 1 8 terminating short of the part adapted to receive said key.

Figure 5 shows a preferred tightening tool or key 11 used to tighten the nipple 8 on each spoke shown in the drawings and it comprises a tubular body portion 12, one end 13 of which is internally splined and dimensioned so that it will slide exactly onto the splined head 10 of each nipple 8.

The exterior of the body portion 12 adjacent the splined end 13 is tapered at 14 as illustrated to facilitate its location in a dimple 1 5 on the wheel rim. A bar 1 7 is fitted through opposite facing holes in the wall of the body portion 12 to provide a T-bar by means of which the key may be rotated.

in order to assemble a wire wheel of the invention using the spokes and nipples just described, a spoke 3, 4 is inserted through a respective hole 6 in the hub portion until its swaged terminal portion 5 seats against the hole 6. Its other threaded end portion is then located in the appropriate hole 7 in the wheel rim whereupon the nipple 8 is screwed onto it until it is finger tight. All the spokes are assembled in this way around the whole of the wheel until they are all finger tight. The spokes are then tightened further to their required predetermined tension using the key 1 , the tightening being done from within the wheel rim 1 rather than externally as with the prior art. Indeed, external tightening of the illustrated nipple would not be possible because the portion thereof extending through the wheel rim is circular in cross-section.

It will be noted from Figure 3 that the splined nipple head 10 lies wholly within the dimple 15.

This is important with the illustrated type of nipple because otherwise it might contact an inner tube (not shown) of a tyre fitted to the wheel rim and puncture it. If the wire wheel is to be used with tubeless tyres, a resilient sealing tape would be applied to the wheel rim over all the holes 7 therein prior to assembly. The nipples would then be pushed through this tape during assembly and tightened down onto it so that a portion thereof surrounding each hole 7 would be compressed between the inner surface of the dimple 14 and the nipple head 10 to provide an airtight seal therewith.

The assembly method just described in particularly advantageous in putting together wire wheels which have been chrome plated because any damage to the nipple plating during tightening will be hidden from view by the tyre when it is fitted to the wheel rim so subsequent rusting of the damaged area can no longer detract from the overall appearance of the wheel. Without tightening the spokes from within the wheel rim, the only other way of dealing with damage caused during tightening would be to replate the whole wheel and this would be prohibitively expensive.

Claims (11)

1. A wire wheel comprising a hub portion connected to a separate rim by a plurality of spokes, each spoke being located in a hole in said rim by means of a nipple threadingly mounted thereon and having a head portion which seats against the rim around said hole, tightening means on or in the nipple head portion located inside the rim shaped to be drivingly engaged and rotated by a tightening tool only from within the rim to tension the spoke.

2. A wire wheel as claimed in claim 1 wherein the tightening means on the nipple head portion are provided on the exterior thereof.

3. A wire wheel as claimed in claim 2 wherein the nipple head portion has an external peripheral surface with splines on all or part thereof.

4. A wire wheel as claimed in claim 2 wherein the nipple head portion is square or hexagonal in shape when viewed in plan.

5. A method of assembling a wire wheel having a hub portion connected to a separate wheel rim by means of a plurality of spokes each located in the rim by means of a nipple, the method comprising tensioning the spokes from within the rim to their required predetermined loading using a tightening tool which drivingly engages a shaped part on or in a head portion of the nipple.

6. A tightening tool for use in the method of tightening the spokes of a wheel as claimed in claim 5 wherein the tool comprises a body portion having one end shaped to co-operate with the correspondingly shaped part of the nipple head, the tool having an opposite end provided with means whereby the tool may be rotated to tighten the nipple when it is engaged therewith.

7. A tool as claimed in claim 6 wherein said one end of the tool is internally splined to co-operate with splines on the outer periphery of the nipple head.

8. A tool as claimed in claim 6 wherein said one end is internally square or hexagonal in crosssection to co-operate with a correspondingly externally shaped nipple head.

9. A wire wheel substantially as herein described with reference to Figures 1 to 3 of the accompanying drawings.

10. A nipple substantially as herein described and illustrated in Figure 4 of the accompanying drawings.

11. A tightening tool substantially as herein: described and illustrated in Figure 5 of the accompanying drawings.