GB2180316A

GB2180316A - Adjustable mounting of a component

Info

Publication number: GB2180316A
Application number: GB08621089A
Authority: GB
Inventors: Andrew Boulton Renfrew
Original assignee: Lucas Industries Ltd
Current assignee: ZF International UK Ltd
Priority date: 1985-09-06
Filing date: 1986-09-01
Publication date: 1987-03-25
Anticipated expiration: 2006-09-01
Also published as: GB2180316B; GB8522160D0; FR2587151A1; DE3630550A1; GB8621089D0

Abstract

A component (M) is mounted on a bracket (B) so that it may readily assume a predetermined position. A place (P) is present at one end of the component (M) and a cam (C) is present between the plate (P) and the bracket (B), bosses (8) of the plate (P) being received in slots (15) in the bracket (B) and movable up and down in the slots. The plate (P) has a ridge (9) arranged to co-operate with grooves in the cam (C). Rotation of the cam (C) moves the bosses (8) in the slots (15) and the cooperation of the ridge and grooves causes this movement to be incremental. The arrangement may be used for mounting a small motor having a gear shaft which has to be aligned with another gear and has application in the base of a rotating lamp on police vehicles. <IMAGE>

Description

SPECIFICATION Adjustable mounting of a component in an assembly The invention relates to the adjustable mounting of a component in an assembly e.g. a motor on a support e.g. a bracket, such that the position of the component can easily be adjusted to assume the optimum position relative to a complementary part of the assembly.

The invention is of particular value in the mounting of a small motor on a bracket, the motor having a gear on the shaft, the gear being arranged for engagement with another gear, and where it is necessary to align the motor output shaft gear accurately with respect to the other gear. By way of an example, the motor and its mounting may be incorporated in the base of a rotating lamp of the type used on e.g. police vehicles, the motor being mounted on a bracket below the base with its output shaft extending in a generally horizontal disposition towards the base the perimeter of which has teeth to define gear to co-operate with the gear of the motor output shaft.

It is one object of the invention to provide a means by which a component can easily be mounted on its bracket in an assembly, and the position of the motor may be adjusted incrementally relative to another part of the assembly.

According to one aspect of the invention there is provided an assembly comprising a component (M) and a mounting bracket (B), the position of component (M) relative to another part (21) of the assembly being adjustable characterised by a plate (P) connected to the component (M), the plate (P) being arranged for movement relative to the bracket (B) along one axis and a cam (C) operatively engaged between the bracket (B) and the plate (P), the cam (C) incorporating means (9) by which movement of the cam (C) relative to the bracket (B) or plate (P) causes incremental relative movement between the bracket (B) and the plate (P).

It is a preferred feature of the invention that the plate be provided with a pair of diametrical bosses on each side of the cam, and that complementary engaging means take the form of slots of greater length to receive such bosses be present in the bracket. The cam is mounted so that rotation of the cam will cause the bosses to move correspondingly along one axis in the slots of the bracket. For this purpose it is preferred to provide on one of the engaging faces, preferably on the plate, a ridge, and on the other a circle of ridge engaging grooves.

In a much preferred feature, the component comprises a motor having an output shaft which extends from one end of the motor through relatively wide diameter aligned holes in the plate, cam and bracket to beyond the bracket and ends in a gear to engage a gear arranged adjacent the bracket at right angles to the major axis of the shaft. Because of the plate and cam, the position of the motor on the bracket may readily and incrementally be moved until the gears are properly engaged.

The invention includes a method of making an assembly comprising a component (M), a mounting bracket (B) and another part (21), and adjusting the position of the component (M) relative to the another part (21) characterised by mounting the component (M) on a plate (P) with a rotary cam (C) present between the plate (P) and the bracket (B), the cam incorporating means (9) by which incremental relative movement may take place between the bracket (B) and the plate (P), and then moving the cam (C) until the component (M) is at a predetermined position relative to the bracket (B).

In order that the invention may be well understood it will now be described with reference to the accompanying diagrammatic drawings, in which Figure 1 is an exploded perspective view of the assembly, and Figure 2 is a sectional view of part of an assembly according to Figure 1 incorporated in a rotating lamp.

An electric motor M has an output shaft 1 which extends from one end of the motor housing 2. A pair of aligned holes 3 is present, one on each side of the shaft.

A plate P has on one face two pegs 4 arranged to be received in the holes 3 thereby to secure the motor M to the plate P. The plate P has a central hole 5 and a land 6 located between a pair of opposed inwardly facing shoulders 7, each shoulder carrying a rectangular boss 8. A diametrical ridge 9 extends from the hole 5 to each shoulder 7 on the land 6.

A cam C has a central hole 10. A circular projection 11 is present on one side of the cam C and has a pair of diametrically opposed peripheral flats 12. The centre of the projection 11 is offset from the centre of the camming portion 13 of the cam C.

A mounting bracket B has a circular hole 14 to receive the projection 11 of the cam C. A pair of elongate slots 15 is present, one on each side of the hole 14, the slots 15 being wide enough to receive the bosses 8 of the plate P but being relatively much longer. The holes 5, 10 and 14 are dimensioned so that the shaft 1 of the motor M may extend therethrough. A -U-shaped spring clip 16 is present to hold the parts assembled together, the hooked clip ends 17 being received in holes 18 in the bracket.

To assemble the parts, the projection 11 of the cam C is located in the hole 14 in the bracket B and the plate P is mounted on the bracket B by locating the bosses 8 on the plate P in the slots 15 in the bracket B, the camming portion 13 of the cam C being located on the land 6 of the plate P between the shoulders 7. The side of the camming portion of the cam C facing the plate P is formed with grooves (shown in ghost outline only), extending radially from the centre of the projection 11, which grooves cooperate with the ridges 9 to provide incremental ratcheting rotation of the cam C relative to the plate P.

In this condition rotation of the cam C relative to the plate P and the dracket B by engagement of the flats 12, in either direction, will bring the periphery of the camming portion of the cam C into engagement with the respective one of the shoulders 7 of the plate P, such engagement serving to move the plate P relative to the bracket B on which the cam C is positively located. The slots 15 are larger than the corresponding dimension of the bosses 8 received therein, and thus the plate P is able to move relative to the bracket B under the action of the cam C, to the extent limited by the relative lengths of the slots 15 and the bosses 8, the length dimension of the slots 15 defining the axis along which relative movement takes place.The relative movement is incremental because of the co-operation between the ridges 9 on the plate P and the grooves in the camming portion 13 of the cam C.

With the motor M mounted on the plate P by engagement of the pegs 4 in the holes 3, and the shaft 1 extending through the holes 5, 10 and 11 in the plate P, cam C and bracket B respectively, the spring clip 16 is engaged in the holes 18 in the bracket B, to provide the spring bias for the incremental rotation of the cam C relative to the plate P.

In the condition shown in Figure 2, a gear pinion 20 is present at the end of the shaft 1 to engage the gear train 21 of the base 22 of a rotating reflector. The bracket B can be of L shape, having a first arm Bl being formed to carry the cam C, plate P and the motor M and the other perpendicular arm B2 being bolted to the reflector base 22. The base 22 has a depending circular wall 23 the free edge of which is formed with gear teeth adapted to co-operate with the gear 20 carried by the shaft 1 of the motor M. Operation of the motor M will cause rotation of the lamp base 22 and lamp L about the motor M by engagement of the gears. Rotation of the cam C from outside the assembly by means of the flats 12 can be used to move the gear up and down (as seen in Figure 2), relative to the gear teeth 21 until a correct engagement is obtained. This adjustment is simple to achieve, after the parts have been assembled.

The invention is not limited to the embodiment described. For example, the arrangement described may be modified by providing the ridges 9 on the cam C and the co-operating grooves on either the plate P or the bracket B. The perimeter of the hole 5 may be castellated to allow the gears 20 to pass therethrough.

Claims

1. An assembly comprising a component (M) and a mounting bracket (B), the position p.f the component (M) relative to another part (21) of the assembly being adjustable characterised by a plate (P) connected to the component (M), the plate (P) being arranged for movement relative to the bracket (B) along one axis, and a cam (C) operatively engaged between the bracket (B) and the plate (P), the cam (C) incorporating means (9) by which movement of the cam (C) relative to the bracket (B) or plate (P) causes incremental relative movement between the bracket (B) and the plate (P).

2. An assembly according to Claim 1 characterised in that the means (9) comprises a ridge (9) and co-operating grooves disposed on the facing surface of the cam (C) and one of the brackets (B) and the plate (P), rotation of the cam (C) causing relative movement between the bracket (B) and the plate (P).

3. An assembly according to Claim 1 or 2 characterised in that the bracket (B) and the plate (P) are engaged by means of at least one boss (8) on one received in an elongate slot (15) in the other, the length dimension of the slot (15) defining the axis of relative movement.

4. An assembly according to any preceding Claim characterised in that the cam (C) is formed with a circular projection (11) which is received in a corresponding circular hole (14) in one of the members (P, B).

5. An assembly according to Claim 4 characterised in that the cam (C) is received on a land (6) between a pair of opposed shoulders (7) in the other of the bracket (B) and the plate (P), rotation of the cam (C) about the axis of the circular projection (11) in either direction bringing the cam (C) into engagement with a respective one of the shoulders (7), such engagement effecting said relative movement between the bracket (B) and the plate (P).

6. An assembly according to Claim 4 or Claim 5, characterised in that the circular projection (11) is formed with a pair of diametrically opposed peripheral flats (12) by which the cam (C) can be engaged to effect rotation thereof, the flats (12) being accessible through the hole (14).

7. An assembly according to any preceding Claim, characterised by a motor (M) carried by one (P) of the bracket (B) and the plate (P) and having an output shaft (1) extending through aligned holes (5, 10, 14) in the one (P) of the bracket and the plate, the cam (C), and the other (B) of the bracket (B) and the plate (P), whereby relative movement between the bracket (B) and the plate (P) effects move ment of the output shaft (1) relative to the bracket (B) and the plate (P).

8. An assembly according to Claim 7, characterised in that the bracket (B) carries a gear (21) arranged to be engaged by a gear (20) carried by the output shaft (1), the relative movement between the bracket (B) and the plate (P) resulting in corresponding relative movement between the gears (20, 21).

9. An assembly according to Claim 7 or Claim 8 characterised by a spring member (16) acting between the motor (M) and the bracket (B) to secure the motor (M), plate (P) and bracket (B) and cam (C) together.

10. A method of making an assembly comprising a component (M), a mounting bracket (B) and another part (21), and adjusting the position of the component (M) relative to the another part (21) characterised by mounting the component (M) on a plate (P) with a rotary cam (C) present between the plate (P) and the bracket (B), the cam incorporating means (9) by which incremental relative movement may take place between the bracket (B) and the plate (P), and then moving the cam (C) until the component (M) is at a predetermined position relative to the bracket (B).