GB2167717A

GB2167717A - Adjustable track width tractor wheel

Info

Publication number: GB2167717A
Application number: GB08527762A
Authority: GB
Inventors: Edward Williams; Terence Roy Crowe; John Sayer
Original assignee: GKN Sankey Ltd
Current assignee: Sankey Holding Ltd
Priority date: 1984-12-01
Filing date: 1985-11-11
Publication date: 1986-06-04
Also published as: GB8430403D0; DE3541123A1; GB8527762D0; IT8568007A0; FR2574024B1; ES297125Y; IT1183988B; FR2574024A1; IT8554113V0; IN166227B; ES297125U; GB2167717B; DE3541123C2

Abstract

A manually adjustable tractor wheel in which the rim (11) carries a continuous ring (24) of small radial dimension and the disc (10) is bolted to the ring, a spacer (29) is inserted between the disc and the ring. Two continuous rings (33 and 34, or 39, 40) can be provided so that the disc can be bolted to either or the ring (48) may be of zig-zag form. <IMAGE>

Description

SPECIFICATION Tractor wheels This invention relates to manually adjustable wheels, particularly for tractors. Such wheels can be manually adjusted to vary the track of a tractor on which they are fitted. A number of types of such wheel are known. Eight track settings can usually be obtained by reversing the wheel discs with respect to the hubs of the vehicle, reversing the wheel discs with respect to the rims, and by varying the positions of connection of the rims and the discs in directions parallel to the rotary axes of the wheels.

In our British Patent Specification Number 2058686 we have disclosed a manually adjustable tractor wheel which is a considerable advance over prior wheels and which has gained wide acceptance among tractor manufacturers. The fatigue life as compared with conventional manually adjustable tractor wheels is considerably improved.

However, where large tractors are used continuously at their maximum capacity even our improved design may, after considerable use, suffer from service problems.

The specific example of the wheel disclosed in Specification 2058686 has an octagonal disc with the bolts connecting the disc to the rim being arranged in four pairs as described in said specification. We tried to improve the performance of this wheel by increasing the number of connecting bolts to eight pairs but only improved the fatigue life by one and a half to two times.

Conversely, a non-adjustable wheel in which the disc is welded to the rim along the whole of the periphery thereof may have a fatigue life at least as great as four times that of the wheel shown in Specification 2058686 but, of course, the wheel is not adjustable or at least has only two positions obtained by reversing the wheel on the hub.

An object of the invention is to increase the fatigue life of a manually adjustable wheel while still having the possibility of adjusting the vehicle track to the normal eight positions.

There has been disclosed in British Patent Specification No. 1,590,799 a demountable wheel comprising a spoked wheel centre on which is mounted a rim. Figure 8 of the specification shows an arrangement in which two spaced rings are welded to the inner periphery of the rim and are bolted to the centre. The centre has two series of alternating spoke members, each of said series having an axially spaced apart and staggered relation to the other of the series. The ends of the spoke members of one series are bolted to one of the rings and the ends of the spoke members of the other series are bolted to the other of the rings.

The rings are notched to give passage to the ends of the spoke members and it is also mentioned that the rings could be a series of discrete elements.

The problem which the construction described sets out to solve is that of providing a demountable wheel which is axially and radially true and which can be assembled and disassembled without the need for an expert and conscientous mechanic to use his skill and knowledge in these operations.

The specification does not address itself to the problem of increasing the fatigue life of a manually adjustable tractor wheel but to the true running of a demountable wheel. The fact that the rings may be notched or comprise discrete elements and that they are shown as being attached to the rim by stitch welding shows that the patentee was not concerned with fatigue life since such constructions will materially weaken the rings and their attachment to the rim. The wheel described is not adjustable and could not be so because each series of spokes can only be connected to one of the rings and in only one position.

The prior specification therefore addresses itself to an entirely diferent problem to that with which the present invention is concerned.

We have now found a solution to the problem of increasing the fatigue life of an adjustable wheel which gives considerably improved performance over the already improved wheel disclosed in Specification 2058868.

According to one of aspect of the invention we provide a manually adjustable wheel for a vehicle, e.g. a tractor, comprising a rim to receive a tyre and having a well; a disc for mounting the rim on the hub of a vehicle, the disc being of uniform thickness and having an outer peripheral portion offset axially from a central or nave portion of the disc and comprising planar, oppositely facing abutment surfaces spaced apart by the thickness of the disc; a single continuous ring of uniform cross section and small radial dimension welded to the radially inner periphery of the rim well and providing first and second planar, oppositely facing abutment surfaces, the first abutment surfaces lying in a first common plane and the second abutment surfaces lying in a second common plane spaced axially from the first common plane; bolt holes spaced circumferentially of the ring, bolt holes in said portion of the disc and arranged to be aligned with the holes in the ring, bolts received in aligned holes in the ring and the disc, and spacers on the bolts, the latter serving to clamp together the ring and the disc with the spacers therebetween and engaging oppositely facing abutment surfaces on the disc and rim.

According to another aspect of the invention we provide a manually adjustable wheel for a vehicle, e.g. a tractor, comprising a rim to receive a tyre and having a well; a disc for mounting the rim on the hub of a vehicle, the disc being of uniform thickness and having an outer peripheral portion offset axially of the wheel from a central or nave portion of the disc and comprising planar, oppositely facing, abutment surfaces spaced apart by the thickness of the disc; two axially spaced continuous rings each of uniform cross section and small radial dimension welded to the radially inner periphery of the rim well and providing first and second planar, oppositely facing abutment surfaces, the first abutment surfaces lying in a first common plane on one of the rings and the second abutment surfaces lying in a second common plane on the other of the rings so that the rings lie between said common planes; bolt holes spaced circumferentially of the rings, bolt holes in said portion of the disc and arranged to be aligned with the holes in the rings, and bolts received in aligned holes in a single one of the rings and the disc and clamping the two together with one of the abutment surfaces on the disc engaging one of the first and second abutment surfaces on the rings.

Because the or each ring is continuous it stiffens the rim and we have found that, as compared with having separate lugs to which the disc is bolted, the fatigue life is improved since the stresses are reduced. Because the or each ring is of uniform cross section it is strong and is not weakened by notches or changes of section.

Preferably the or each ring is continuously welded to the rim along the whole of the outer periphery of the ring.

Preferably also, the disc has substantially the shape of a square with the corners cut off so that the disc has an irregular octagonal shape with four shorter sides and four longer sides arranged alternately around the outer peripheral portion of the octagon, said periphery being offset from the centre or nave of the disc; the bolt holes in the ring or rings being arranged in pairs with the spacing between the holes of each pair being less than the circumferential spacing between adjacent holes of adjacent pairs, the bolt holes in said peripheral portion of the disc also being arranged in pairs in the shorter sides of the octagon.

Preferably the or each ring is made of sheet material i.e. sheet metal, and is T-butt welded to the rim along the whole of the outer periphery of the ring. The or each ring may be planar.

In another arrangement there may be a single ring of zig-zag shape and of uniform cross section with first parts thereof spaced axially of the rotary axis of the wheel with respect to second parts thereof, each of said first and second parts providing an abutment surface and having a pair of bolt holes therein; the disc being selectively connectable to said first parts or to said second parts by said bolts to obtain the necessary adjustability.

The or each ring may be made up of a number of separate pieces so long as they are rigidly connected together to form a continuous ring. Preferably the rings are made from circled and buttwelded strip of uniform cross section but could be made from sheet metal by cutting circles.

Various embodiments of the invention will now be described in detail by way of example with reference to the accompanying drawings in which: Figure 1 is an elevation of a wheel embodying the invention; Figure 2 is a detail section through a first em- bodiment of the invention; Figure 3 is a similar section through a second embodiment of the invention; Figure 4 is a similar section through a third embodiment of the invention; Figure 5 is a similar section through a further embodiment of the invention; and Figure 6 illustates possilbe joint formations in the ring.

Referring now to Figures 1 and 2 the wheel comprises a disc 10 a rim 11.

As will be seen from Figure 1, the disc has the shape of a square with its corners cut off so as to provide an irregular octagon having four longer sides 12 and four shorter sides 13 arranged alternately round the periphery of the octagon. As will be seen from Figure 2, the disc is of uniform thickness, and has a planar outer peripheral portion 14, which provides planar abutment surfaces 14a and 14b spaced apart by the thickness of the disc, a conical portion 15 and a planar central portion or nave 16 parallel to the peripheral portion 14 and offset axially therefrom. The central portion 16 is provided with a central aperture 17 and holes 18 whereby the disc can be secured to a vehicle hub, not shown.

The disc has, in each of its shorter sides 13, two bolt holes indicated at 19. The spacing between the bolt holes of each pair in a side 13 is less than the spacing between adjacent bolt holes in adjacent sides 13.

Referring now to Figure 2, the rim has a well base 20, and well side walls 21 which merge into ledges partially shown at 22; outwardly of the ledges are the bead seats and tyre-retaining flanges (not shown).

Welded at 23 to the inner and periphery of the well base 20 is a sheet metal ring 24 of constant cross section small radial dimension. Its radial dimension is similar to the radial dimension of the peripheral portion 14 of the disc. The ring is continuous and the ends of the ring may be welded together in either of the manners shown for example in Figure 6 or in some other manner. The ring 24 is planar, providing oppositely-facing first and second planar abutment surfaces 24a and 24b which lie in first and second common planes respectively, and is T-Butt welded to the well base 20. The weld 23 is continuous around the whole periphery of the ring.

The ring 24 is provided with holes 25. The holes 25 are arranged in pairs at the same spacing as the holes 19 so that the holes 19 can be aligned with the holes 25.

The disc is secured to the ring by eight bolts, one of which is shown at 26 in Figure 2. Each bolt has a head 27 which engages the ring 24 and a shank 28 which passes through the holes 19 and 25 and which also carries a spacer 29, the spacer being located between the ring 24 and the peripheral part 14 of the disc. The shank 27 carries a washer 30 and nut 31 which holds the disc 10, spacer 29 and the ring 24 together. The spacer 29 may be common to a pair of bolts 26. The spacers 29 are engaged by the oppositely-facing abutment surfaces 14b and 24b on the disc and ring respectively.

The arrangement shown gives eight possible track settings. Thus one track setting is as shown in Figure 2, a second track setting is as shown in Figure 2 but with the conical part of the disc being arranged to extend to the right of the ring 24 in Figure 2 rather than to the left as shown.

Two further settings are obtainable by bolting the disc 10 to the other side of the ring 24 as indicated in dotted lines at 10 a in Figure 2, the spacers being arranged to the left of the ring 24 as shown in dotted lines also in that figure. The conical part 15 of the disc may be arranged to go either way to provide two settings.

This gives four settings. These settings may be multiplied by two by turning the rim around relative to the hub, not shown, of the vehicle in each of the four settings of the disc and hub described above.

Figure 3 shows a second embodiment in which there are two two planar rings welded to the inner periphery of the rim. Thus the rim is indicated generally at 32 and the two rings are indicated at 33 and 34. The rings provide oppositely-facing first and second abutment surfaces 33a and 34a respectively. The surfaces 33a lie in a first common plane and the surfaces 34a in a second common plane.

The disc 35 is shown bolted to the ring 34 by a bolt and nut assembly 36. The disc has oppositely facing abutment surfaces 35a and 35b which lie in common planes respectively. In this instance spacers are not required and the surfaces 34a and 35a are in engagement. There are eight bolt holes such as 37 arranged in each ring 33 and 34 in a manner similar to the holes arranged in the ring 24 in Figure 2. The disc can also be secured to the ring 33 in the dotted line position shown at 36 in which case the surfaces 33a and 35b are in engagement. Each ring 33 and 34 will have sixteen holes in it in all. There will be the eight bolt holes such as 37 to receive the bolts 36 arranged in pairs as described. These holes 37 in one ring will be staggered relative to the corresponding holes in the other ring.There will also be eight clearance holes in each ring, one such hole being shown at 38 in the ring 33, the clearance holes 38 in the ring 33 being aligned with the holes 37 in the ring 34 so as to enable the bolts 36 to be inserted into the holes 37. Similarly there will be clearance holes such as 38 in the ring 34 in alignment with the holes such as 37 in the ring 34.

The arrangement of Figure 2 will give eight positions of track as described in relation to Figure 2 i.e. two as shown in the Figure 3, one in full lines and one in dotted lines, two obtained by reversing the rim in each of the positions shown in Figure 3 and another four by changing the position of the disc on the hub as described.

The arrangement shown in Figure 4 is similar to the arrangement shown in Figure 3 except that the two rings 39 and 40 there shown are more widely spaced than the rings 33 and 34 and are welded to the well base of the rim 41. In this construction, the eight bolt holes 42 in the ring 39 can be in alignment with the eight bolt holes 43 in the ring 40 if desired since the nut and bolt assemblies such as 44 can be inserted between the two rings and it is not necessary to have the clearance holes such as 38 described in relation to Figure 3. It is believed that it will be self evident that the disc 45 may be bolted either to the ring 39 or to the ring 40 as shown and again that the rim may be turned to produce different positions and the disc turned on the hub.

Finally, in Figure 5, a ring of zig-zag shape is shown. The rim is indicated at 46 and the disc at 47. The ring is indicated generally at 48 and includes a plurality of first portions 49 and a plurality of second portions 50. Only one of each of said portions is shown. The portions 49 and 50 are arranged perpendicular to the rotary axis of the wheel but are spaced axially of the rotary axis.

There are four first portions 49 and four second portions 50 spaced alternately around the periphery of the wheel so that the bolt holes 19 in the disc can be aligned either with the bolt holes in the first portions 49 or with the bolt holes in the second portions 50. When the disc is secured to the portions 49 it is in the position shown in full lines in Figure 5 and is retained in position by nut and bolt assemblies 51. When the disc is secured to the second portions 50 it is in the dotted line position 52.

The zig-zag ring 48 is welded around the whole of its outer periphery by a weld, not shown, to the inner periphery of the rim 46.

In all the embodiments there is a continuous weld between the or each ring 24, 33, 34, 39, 40 and 48 and the rim so as to provide a continuous means of transferring loads between the disc and the rim.

In all the embodiments the disc has the shape as described with reference to Figures 1 and 2.

The invention provides an improved tractor wheel suitable for heavy duty use on large tractors being used at maximum power.

Claims

1. A manually adjustable wheel for a vehicle, e.g. a tractor, comprising a rim to receive a tyre and having a well; a disc for mounting the rim on the hub of a vehicle, the disc being of uniform thickness and having an outer peripheral portion offset axially from a central or nave portion of the disc and comprising planar, oppositely facing abutment surfaces spaced apart by the thickness of the disc; a single continuous ring of uniform cross section and small radial dimension welded to the radially inner periphery of the rim well and providing first and second planar, oppositely facing abutment surfaces, the first abutment surfaces lying in a first common plane and the second abutment surfaces lying in a second common plane spaced axially from the first common plane; bolt holes spaced circumferentially of the ring, bolt holes in said portion of the disc and arranged to be aligned with the holes in the ring, bolts received in aligned holes in the ring and the disc, and spacers on the bolts, the latter serving to clamp together the ring and the disc with the spacers therebetween and engaging oppositely facing abutment surfaces on the disc and rim.

2. A manually adjustable wheel for a vehicle, e.g. a tractor, comprising a rim to receive a tyre and having a well; a disc for mounting the rim on the hub of a vehicle, the disc being of uniform thickness and having an outer peripheral portion offset axially of the wheel from a central or nave portion of the disc and comprising planar, oppositely facing, abutment surfaces spaced apart by the thickness of the disc; two axially spaced continuous rings each of uniform cross section and small radial dimension welded to the radially inner periphery of the rim well and providing first and second planar, oppositely facing abutment surfaces, the first abutment surfaces lying in a first common plane on one of the rings and the second abutment surfaces lying in a second common plane on the other of the rings so that the rings lie between said common planes; bolt holes spaced circumferentially of the rings, bolt holes in said portion of the disc and arranged to be aligned with the holes in the rings, and bolts received in aligned holes in a single one of the rings and the disc and clamping the two together with one of the abutment surfaces on the disc engaging one of the first and second abutment surfaces on the rings.

3. A wheel according to Claim 1 wherein the or each ring is continuously welded to the rim along the whole of the outer pheriphery of the ring.

4. A wheel according to any one of the preceding claims, wherein the disc has substantially the shape of a square with the corners cut off so that the disc has an irregular octagonal shape with four shorter sides and four longer sides arranged alternately around said outer peripheral portion of the octagon, said portion being offset axially from the centre or nave of the disc; the bolt holes in the ring or rings being arranged in pairs with the spacing between the holes of each pair being less than the circumferential spacing between adjacent holes of adjacent pairs, the bolt holes in said peripheral portion of the disc also being arranged in pairs in the shorter sides of the octagon.

5. A wheel according to any one of the preceding Claims, wherein the ring is made of sheet material and is T-butt welded to the rim.

6. A wheel according to any one of the preceding claims wherein the or each ring is planar.

7. A wheel according to any one of Claims 1, 3, or 4 when dependent from Claim 1 or Claim 3, and Claim 5 wherein the ring is of zig-zag shape and of uniform cross section with first portions thereof being spaced axially with respect to second portions thereof, each of said first and second portions providing an abutment surface and having a pair of bolt holes therein, the disc being selectively connectable to said first and second portions by said bolts.

8. A wheel substantially as hereinbefore described with reference to Figure 1 and any one of Figures 2 to 5 of the accompanying drawings.

New claims or amendments to claims filed on 2.1.86.

Superseded claims 1-8.

New or amended claims: CLAIMS

1. A manually adjustable wheel for a vehicle, e.g. a tractor, comprising a rim to receive a tyre and having a well; a disc for mounting the rim on the hub of a vehicle, the disc being of uniform thickness and having an outer peripheral portion offset axially from a central or nave portion of the disc and comprising planar oppositely facing abutment surfaces spaced apart by the thickness of the disc; a single continuous ring of uniform cross section and small radial dimension welded to the radially inner periphery of the rim well and providing first and second planar, oppositely facing abutment surfaces, the first abutment surfaces lying in a first common plane and the second abutment surfaces lying in a second common plane spaced axially from the first common plane; bolt holes spaced circumferentially of the ring, bolt holes in said portion of the disc and arranged to be aligned with the holes in the ring, bolts received in aligned holes in the ring and the disc, and spacers on the bolts, the latter serving to clamp together the ring and the disc with the spacers therebetween and engaging oppositely facing abutment surfaces on the disc and ring.

3. A manually adjustable wheel for a vehicle, e.g. a tractor, comprising a rim to receive a tyre and having a well, a disc for mounting the rim on the hub of a vehicle, the disc being of uniform thickness and having an outer peripheral portion offset axially from a central or nave portion of the disc and comprising planar, oppositely facing abutment surfaces spaced apart by the thickness of the disc; a single continuous ring of zig-zag shape, of uniform cross section and small radial dimension welded to the radially inner periphery of the rim well, first portions of the ring being spaced axially from second portions of the ring, said first and second portions providing first and second planar, oppositely facing abutment surfaces respectively, the first abutment surfaces lying in a first common plane and the second abutment surfaces lying in a second common plane spaced axially from the first common plane, a pair of bolt holes in each portion of the ring, bolt holes in said portion of the disc and arranged to be aligned with the holes in the ring and bolts received in aligned holes in the ring and the disc and serving to clamp together the ring and the disc with oppositely facing abutment surfaces on the disc and ring engaging one another.

4. A wheel according to any one of Claims 1 to 3 wherein the or each ring is continuously welded to the rim along the whole of the outer periphery of the ring.

5. A wheel according to any one of the preceding claims, wherein the disc has substantially the shape of a square with the corners cut off so that the disc has an irregular octagonal shape with four shorter sides and four longer sides arranged alternately around said outer peripheral portion of the octagon, said portion being offset axially from the centre or nave of the disc; the bolt holes in the ring or rings being arranged in pairs with the spacing between the holes of each pair being less than the circumferential spacing between adjacent holes of adjacent pairs, the bolt holes in said peripheral portion of the disc also being arranged in pairs in the shorter sides of the octagon.

6. A wheel according to any one of the preceding Claims, wherein the ring is made of sheet material and is T-butt welded to the rim.

7. A wheel according to any one of the preceding claims wherein the or each ring is planar.