GB2089739A

GB2089739A - Dual wheel assembly

Info

Publication number: GB2089739A
Application number: GB8136490A
Authority: GB
Original assignee: Korte & Kni Kortteen Konepaja
Current assignee: Korte & Kni Kortteen Konepaja
Priority date: 1980-12-19
Filing date: 1981-12-03
Publication date: 1982-06-30
Also published as: IT1144530B; FI803971L; FR2496561B1; DK153817B; BR8108215A; SE8107552L; GB2089739B; IT8149889A0; SE440887B; DE3148701A1; FI63692C; DK153817C; FI63692B; FR2496561A1; DK556881A

Abstract

A dual wheel assembly for a tractor or a similar working machine comprises an outer auxiliary wheel (4) and an inner wheel (1), the rim (5) of the auxiliary wheel (4) being extended to form an axial flange provided with a locking wedge (6) arranged to cooperate with a wedge (7) on the rim (2) of the inner wheel to interlock the rims as a result of relative rotary motion of the rims around their common axis of rotation, means being provided to releasably secure the wedges in their locked position. The auxiliary rim (5) is made from a cylindrical blank. <IMAGE>

Description

SPECIFICATION Wheel assembly for a tractor or similar working machine The present invention relates to an arrangement in a pair of wheels of a tractor or a similar working machine wherein an outer auxiliary wheel is fastened by means of a clamping means in parallel to an inner wheel whereby the edge of the rim of said auxiliary wheel facing said inner wheel is extended to form a circular flange projecting outwardly from the tyre. Such constructions are common and are being used more and more widely. The advantages included an improved carrying capacity, a reduced surface pressure, a reduced soil compaction and less slippage.Drawbacks have primarily included the high price of the auxiliary equipment and awkward and laborious manufacturing methods which, in addition, require a large number of various loose and moving parts which all prevent, when the auxiliary wheel is installed, maintenance of the mountings of the tractor's own wheel system and tightening of the screws by means of conventional spanners.

One known construction is described, e.g., in the same applicant's earlier Finnish Patent Specification 49,692. This known construction suffers from the disadvantage of a relatively complicated construction including a plurality of loose parts, which increases the manufacturing costs. Another drawback comprises the disadvantages caused by tightening. In this known construction the tightening is effected parallel to the common axis of the rims which, in practice, has proved to be awkward.

The object of the present invention is to provide a simplified method for manufacturing and installing an auxiliary wheel which method, because of its mounting is suited for wheels of all sizes regardless of tightening bolt pitch differences used in various tractor marks and rim types.

An arrangement in a pair of wheels of a tractor according to the invention is characterized in that the rim of said auxiliary wheel is made by shaping of a continuous blank, and in that said rim of the auxiliary wheel and the rim of said inner wheel are each provided with at least one locking wedge substantially parallel to the periphery of the rim, said locking wedges being arranged to lean against each other and to interlock said rims as a result of the relatively rotary movement of the rims around their common axis of rotation.

An advantage of the auxiliary wheel assembly according to the invention over the prior art assembly lies is a simple and extremely reliable mounting and an inexpensive construction because it requires no expensive central crank tightening methods but the rim cylinder is completely empty on the inside with the exception of one tightening screw. However, it is low against the extended rim and, hence, does not interfere with the tightening of the tractor's own rim centre bolts nor with their check-ups and maintenance since no additional mountings are required thereunder. The manufacture of the auxiliary rim can also be easily automatized since, for example, no welding is used in the manufacture of the rim itself.

The invention will now be described by means of an embodiment with reference to the accompanying drawing in which Figure 1 is a partial vertical section of a rear wheel of a tractor and an auxiliary tyre arranged adjacent thereto on the outer side, and Figure 2 shows wedging inclined surfaces and one tightening alternative.

Figure 1 shows in partial section a tractor's rear tyre proper 1 mounted on a rim 2. The rim is provided with a plurality of lugs 3 by means of which the rear wheel is in a conventional manner removably fastened on a hub disc by means of bolts. An auxiliary tyre 4 is mounted on an auxiliary rim 5.

According to the invention, this auxiliary rim is made, for example, of a cylindrical blank by means of shaping only. Thus, the additional rim is completely unbroken without any welds or similar.

The shaped additional rim 5 is fastened on the tractor's rear wheel proper by means of at least one locking wedge 6,7 in each rim and by means of a conical surface of the counter-rim. Tightening is effected, for example, by rotating the additional rim 5 in relation to the rim 2 around their common axis of rotation by means of a tightening screw, a pawl of an eccentric crank or similar 8.

Removal of the wheel is effected by unscrewing the tightening screw 8 whereby the rim 5 is able to rotate relatively with respect to the rim due to which the connection formed by the inclined surfaces of the locking wedges 6,7 is opened. Hereafter a locking pin at one end of the screw 8 can be removed and the wheel swung out of its position.

Large wheels can also be locked by moving the tractor's own wheel with a sudden jerk whereby the inclined surface of the locking wedge 7 in the rim 2 abuts on the locking wedge 6 of the auxiliary rim 5 while at the same time pulling the additional rim tightly against the rim proper which produces a secure engagement. The rim is by means of said tightening screw prevented from unlocking when backing the tractor.

When removing the wheel, the tightening screw is unscrewed so as to loosen the locking pin of the tightening screw in its hole for removal thereof whereafterthetractorwheel is pulled by backing with a sudden jerk whereby the rim, while rotating, moves with respect to the additional rim so that the locking wedges are released from the position shown in Figure 2 whereby the auxiliary wheel can be swung out of its position.

1. Awheel assembly for a tractor or similar working machine comprising an outer auxiliary wheel fastened by means of a clamping means in parallel to an inner wheel the edge of the rim of said auxiliary wheel facing said inner wheel being extended to form a circular flange projecting outwardly from the tyre, wherein the rim of said auxiliary wheel is made by shaping from a continuous blank, and said rim and that of said inner wheel are each provided with at least one locking wedge substan

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Wheel assembly for a tractor or similar working machine The present invention relates to an arrangement in a pair of wheels of a tractor or a similar working machine wherein an outer auxiliary wheel is fastened by means of a clamping means in parallel to an inner wheel whereby the edge of the rim of said auxiliary wheel facing said inner wheel is extended to form a circular flange projecting outwardly from the tyre. Such constructions are common and are being used more and more widely. The advantages included an improved carrying capacity, a reduced surface pressure, a reduced soil compaction and less slippage.Drawbacks have primarily included the high price of the auxiliary equipment and awkward and laborious manufacturing methods which, in addition, require a large number of various loose and moving parts which all prevent, when the auxiliary wheel is installed, maintenance of the mountings of the tractor's own wheel system and tightening of the screws by means of conventional spanners. One known construction is described, e.g., in the same applicant's earlier Finnish Patent Specification 49,692. This known construction suffers from the disadvantage of a relatively complicated construction including a plurality of loose parts, which increases the manufacturing costs. Another drawback comprises the disadvantages caused by tightening. In this known construction the tightening is effected parallel to the common axis of the rims which, in practice, has proved to be awkward. The object of the present invention is to provide a simplified method for manufacturing and installing an auxiliary wheel which method, because of its mounting is suited for wheels of all sizes regardless of tightening bolt pitch differences used in various tractor marks and rim types. An arrangement in a pair of wheels of a tractor according to the invention is characterized in that the rim of said auxiliary wheel is made by shaping of a continuous blank, and in that said rim of the auxiliary wheel and the rim of said inner wheel are each provided with at least one locking wedge substantially parallel to the periphery of the rim, said locking wedges being arranged to lean against each other and to interlock said rims as a result of the relatively rotary movement of the rims around their common axis of rotation. An advantage of the auxiliary wheel assembly according to the invention over the prior art assembly lies is a simple and extremely reliable mounting and an inexpensive construction because it requires no expensive central crank tightening methods but the rim cylinder is completely empty on the inside with the exception of one tightening screw. However, it is low against the extended rim and, hence, does not interfere with the tightening of the tractor's own rim centre bolts nor with their check-ups and maintenance since no additional mountings are required thereunder. The manufacture of the auxiliary rim can also be easily automatized since, for example, no welding is used in the manufacture of the rim itself. The invention will now be described by means of an embodiment with reference to the accompanying drawing in which Figure 1 is a partial vertical section of a rear wheel of a tractor and an auxiliary tyre arranged adjacent thereto on the outer side, and Figure 2 shows wedging inclined surfaces and one tightening alternative. Figure 1 shows in partial section a tractor's rear tyre proper 1 mounted on a rim 2. The rim is provided with a plurality of lugs 3 by means of which the rear wheel is in a conventional manner removably fastened on a hub disc by means of bolts. An auxiliary tyre 4 is mounted on an auxiliary rim 5. According to the invention, this auxiliary rim is made, for example, of a cylindrical blank by means of shaping only. Thus, the additional rim is completely unbroken without any welds or similar. The shaped additional rim 5 is fastened on the tractor's rear wheel proper by means of at least one locking wedge 6,7 in each rim and by means of a conical surface of the counter-rim. Tightening is effected, for example, by rotating the additional rim 5 in relation to the rim 2 around their common axis of rotation by means of a tightening screw, a pawl of an eccentric crank or similar 8. Removal of the wheel is effected by unscrewing the tightening screw 8 whereby the rim 5 is able to rotate relatively with respect to the rim due to which the connection formed by the inclined surfaces of the locking wedges 6,7 is opened. Hereafter a locking pin at one end of the screw 8 can be removed and the wheel swung out of its position. Large wheels can also be locked by moving the tractor's own wheel with a sudden jerk whereby the inclined surface of the locking wedge 7 in the rim 2 abuts on the locking wedge 6 of the auxiliary rim 5 while at the same time pulling the additional rim tightly against the rim proper which produces a secure engagement. The rim is by means of said tightening screw prevented from unlocking when backing the tractor. When removing the wheel, the tightening screw is unscrewed so as to loosen the locking pin of the tightening screw in its hole for removal thereof whereafterthetractorwheel is pulled by backing with a sudden jerk whereby the rim, while rotating, moves with respect to the additional rim so that the locking wedges are released from the position shown in Figure 2 whereby the auxiliary wheel can be swung out of its position. CLAIMS

1. Awheel assembly for a tractor or similar working machine comprising an outer auxiliary wheel fastened by means of a clamping means in parallel to an inner wheel the edge of the rim of said auxiliary wheel facing said inner wheel being extended to form a circular flange projecting outwardly from the tyre, wherein the rim of said auxiliary wheel is made by shaping from a continuous blank, and said rim and that of said inner wheel are each provided with at least one locking wedge substan tially parallel to the periphery of the rim, said locking wedges being arranged to engage against each other and to interlock said rims by means of relative rotary movement of the rims about their common axis of rotation.

2. An assembly according to claim 1, wherein said relative locking rotary movement of said rims is arranged to be effected by means of a tightening screw substantially parallel to the periphery of the rims and fastened to said locking wedges or by means of any other corresponding part producing a rotary movement.

3. Awheel assemblyforatractor or similar working machine substantially as hereinbefore described with reference to the accompanying drawings.