Conventionally sensor mountings comprise a mounting block which is either welded onto, or bolted to, an axle beam or stub axle (hereinafter referred to as an axle beam), or bolted to a bracket welded to an axle beam. It has a machined bore into which a tongued spring metal sleeve is inserted. The sensor is pushed into the sleeve, which retains it.

This invention provides a simple construction, facilitates retro-fitting and avoids possible stress raisers which might be occasioned by welding.

According to one aspect the present invention consists in a sensor mounting comprising an axle beam having a journal for a bearing assembly for a hub to be rotatably mounted on the axle beam and a sensor mounting block, characterised in that a recess is provided in the axle beam inboard of the journal, the sensor mounting block has at least one lug adapted to engage in and be located by the recess, and there disengageable securing means secures the located sensor mounting block to the axle beam.

Preferably the sensor mounting block has two spaced lugs.

The lug or lugs of the sensor mounting block may extend substantially radially of the axle beam in the assembled mounting.

The recess may conveniently comprise a circumferential groove formed, as by machining, in the axle beam.

The securing means may conveniently comprise, in combination, a drilled and tapped hole in the axle beam in or adjacent to the recess, a hole through the sensor mounting block and a bolt whose shank passes through the hole in the sensor mounting block and is received in the tapped hole. When the sensor mounting block has two spaced lugs, as preferred, the hole in the sensor mounting block is preferably between the two lugs. The bolt may be locked by known means such as a lock washer, spring washer or thread adhesive.

The axle beam will usually have a recess towards each end to receive, locate and mount a sensor mounting block for each hub/wheel assembly.

Usually a seal assembly is mounted on the axle beam inboard of the hub bearing assembly and, where this is the case, the recess for the sensor mounting block will be provided inboard of the journal for the seal assembly, which is itself inboard of the journal for the bearing assembly.

According to a second aspect the present invention consists in a vehicle axle having an axle beam and a sensor mounting and characterised in that the sensor mounting is in accordance with the first aspect of the invention herein set forth.

According to a third aspect the present invention consists in a sensor mounting block characterised in that it has at least one lug adapted to be received in a location on an axle beam for a sensor mounting block.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a plan view of a sensor mounting block; Figure 2 is a section on line A-A through the mounting block of Figure 1; Figure 3 is a view on arrow D of Figure 2; Figure 4 is a section on line B-B of Figure 1, and Figure 5 is a scrap view of an axle beam having a recess to receive and locate a sensor mounting block.

Referring to Figures 1 to 4 of the drawings, a sensor mounting block 1 of a sensor mounting has a through bore 2 for reception of a tongued spring metal sleeve (not shown) into which a sensor (not shown) is inserted.

The sensor mounting block 1 has a flange portion 3, the underside of which is recessed at 4 and a through hole 5 is provided to receive the shank of a bolt (not shown). Two inclined lugs 6 extend from the lower surface of the mounting block 1.

Turning now to Figure 5, this is a scrap view towards one end of a tubular axle beam 7. Surface 8 of the axle beam 7 constitutes a journal for a hub bearing assembly, not shown, and surface 9 constitutes a journal for a seal assembly, not shown, for the bearing assembly. A recess, in

the form of an annular groove 11, is provided in the axle beam 7 inboard of the journal 9.

The sensor mounting is assembled by engaging the lugs 6 of the sensor mounting block 1 in the groove 11 of the axle beam 7 so as to align the hole 5 with a drilled and tapped hole (not shown) in the axle beam which is centred in the groove 11. Insertion and securing of a bolt, not shown, completes the assembly.

When assembling the axle a sensor (which is of generally cylindrical construction) is inserted in the tongued spring metal sleeve so as to extend beyond the sleeve.

When the hub and bearing assembly is fitted an exciter ring secured to the hub pushes the sensor back to a correct adjusted position in which the sleeve retains it.