GB2189201A

GB2189201A - Wheels

Info

Publication number: GB2189201A
Application number: GB08609579A
Authority: GB
Inventors: Raymond William Powell
Original assignee: Dunlop Ltd
Current assignee: Dunlop Ltd
Priority date: 1986-04-18
Filing date: 1986-04-18
Publication date: 1987-10-21
Anticipated expiration: 2006-04-18
Also published as: GB8609579D0; DE3712774A1; FR2597410B1; GB2189201B; JPS62255201A; FR2597410A1

Description

GB 2 189 201 A 1 SPECIFICATION board edge of each land this object can be

achieved.

Wheels One embodiment of the invention will now be described, with reference to the accom This invention relates to wheels for pneumatic 70 panying drawings, in which:

tyres, and particularly to motor wheels of the Figure 1 is a diagrammatic axial cross-sec kind which comprises a pressed-metal wheel tional view of a wheel; centre and a roll-formed rim which interfit and Figure 2 is an end view of the wheel shown are welded together to form the completed in Fig. 1, as seen from the right-hand (in wheel. 75 board) side of the drawing; Such wheels are subject to increasingly Figure 3 is a detail view, as seen, from the stringent requirements, set by the vehicle wheel axis, showing a conventional weld be manufacturers, for accuracy in the true-running tween the disc and rim, and of the wheel. It is desirable for some applica- Figures 4 and 5 are similar views to that of tions, when the wheel is located on an axle 80 Fig. 3, showing embodiments of the invention.

and rotated, that the maximum variation in ra- As shown in Figs. 1 and 2, a wheel 10 dius (radial run-out) measured at the tyre bead comprises a generally cup- shaped pressed seats is no more than 0.5 millimetres. sheet-metal (steel) disc portion 12 and a Whilst every effort is made to produce the sheet-metal (steel) rim portion 14.

rim and disc components to a high degree of 85 The rim portion 14 is of conventional form, accuracy it has been found from experience incorporating a well-base portion 16, inboard that when they are welded together distor- and outboard tyre bead seats 18, 19 respec tions occur which may cause the assembled tively and flanges 20,21.

wheel to have variations in radius around the The disc portion 12 has a central hole 24, circumference of its bead seats which are 90 wheel fixing stud holes 25 and an axially greater than the desired tolerance. turned outer flange portion 28 which extends One object of the present invention is to in an axially inboard direction in closely fitting provide a wheel of the kind described having relationship within the radially inner surface of improved uniformity in respect of radial run- the wheel rim portion 14.

out. 95 The disc portion 12 and rim portion 14 are, According to the invention, a wheel com- conventionally, welded together as shown in prises a cup-shaped pressed-metal disc por- Figs. 1-3, by means of four fillet or seam tion and a rim portion secured together by welds 30. These welds, as shown in Fig. 3, welding, the disc portion having a plurality of are each made at the axially inboard edge 32 axially extending land portions fitting closely 100 of a land portion 34 (it is normal practice in within the radially inner surface of the rim and the preparation of a wheel disc from rectangu being welded thereto by seam or fillet welds, lar stock to produce first an octagonal shape two or more of such welds being arranged and then press to a cup-shape in which land with respect to each land portion along the portions 34 alternate with scallop portions 36 axially inboard edge thereof so that the welds 105 in consequence of the original shape of the are spaced relative to one another. blank).

The term -inboard- relates to the side of Fig. 4 shows one embodiment of the inven the wheel which will face inboard of a vehicle tion in which the weld 30 (which may be from to which the wheel is intended to be fitted. 60 millimetres to 100 millimetres in circumfer This invention as defined above is based on 110 ential length, is replaced by two widely sepa the discovery that the heat which is necessa- rated shorter welds 40, 42. The combined rily applied to the disc during the welding pro- length of the shorter welds 40 and 42 may cess causes distortions to occur in the metal be less than that of the weld 30, for example of the disc portion which tend to expand, in 20% less, since the positioning of the welds the radial sense, the land portions of the disc. 115 40, 42 adjacent the ends 44, 46 of the land This causes a regular variation in rim radius portion 34 tends to provide greater strength around its circumference, high points being than would be provided by a similar length of noted, especially in respect of the inboard rim weld in the central region 48 of the edge 32.

seat, in positions where a land of the disc is The change from a conventional weld ar welded to the rim. The effect is accentuated 120 rangement as illustrated in Figs. 2 and 3 to when the rim is thin relative to the disc, and that in accordance with the invention as is thought to be due to the effect of welding shown in Fig. 4 has the advantage of reducing heat permitting the relaxation of stresses the amount of heat transmitted to the wheel which were previously set into the disc during disc during the welding process, and hence the pressing of the disc to a cup-shape. The 125 reducing the temperature to which the wheel invention has the object of reducing the disc is raised by the welding. Any radial dis transmission of heat into the disc, and it has tortion of the disc caused by the welds 40, been found that by substituting, for example, 42 in accordance with the invention is there two separate, short, welds for the previously fore less than that caused by the weld 30, employed single, long, seam weld at the in- 130 and instead of a single relatively large distort- 2 GB 2 189 201 A 2 ing effect two relatively smaller distortions Printed for Her Majesty's Stationery Office may occur. This has the beneficial effect of by Burgess & Son (Abingdon) Ltd, Dd 8991685, 1987.

enabling a wheel having a more uniform radial Published at The Patent Office, 25 Southampton Buildings, run-out characteristic to be produced, with a London, WC2A l AY, from which copies may be obtained.

reduced maximum variation.

As shown in Fig. 5, another embodiment of the invention comprises four welds 50, 52, 54, 56 disposed in evenly-spaced positions along the axially inboard edge 32 of the land portion 34. This arrangement also has the advantage that each weld transmits a reduced amount of heat into the disc portion, and a single relatively large distortion is replaced by four smaller distortions.

The welding process used for the production of a wheel as illustrated in Fig. 4 or Fig. 5 is generally conventional such as the MIG process. Four welding heads may be employed, one for each of the four land portions, with indexing apparatus for bringing each welding head successively to the positions indicated in the drawings to make the welds 40, 42 or 50, 52, 54, 56. By taking advantage of the possibility of using shorter welds (in total length), useful savings in material costs and production times can be obtained.

Claims

1. A wheel Comprising a cup-shaped pressed-metal disc portion and a rim portion secured together by welds, the disc portion having a plurality of axially extending land portions fitting closely within the radially inner surface of the rim and being welded thereto by seam or fillet welds, two or more of such welds being arranged with respect to each land portion along the axially inboard edge thereof so that the welds are spaced relative to one another.

2. A wheel according to Claim 1 wherein each land portion has two welds lying adja cent opposite ends (in the circumferential sense) of the land portion.

3. A wheel according to Claim 1 or Claim 2 wherein each land portion has a series of welds uniformly spaced along the axially inboard edge thereof.

CLAIMS Amendments to the claims have been filed, and have the following effect:- New or textually amended claims have been filed as follows:-

4. A wheel according to Claim 1 con- structed and arranged substantially as described in the accompanying Description and illustrated in Figs. 1, 2, and 4 of the accompanying drawings.

5. A wheel according to Claim 1 con- structed and arranged substantially as described in the accompanying Description and illustrated in Figs. 1, 2 and 5 of the accompanying drawings.