GB2213649A

GB2213649A - Switch rockers

Info

Publication number: GB2213649A
Application number: GB8908779A
Authority: GB
Inventors: Victor Russam
Original assignee: Ashley Accessories Ltd
Current assignee: Ashley Accessories Ltd
Priority date: 1985-03-01
Filing date: 1989-04-19
Publication date: 1989-08-16
Also published as: GB2213649B; GB8908779D0; GB8505370D0

Abstract

A rocker for a switched electrical accessory comprises a rocker body 110 and a separate member 130 which provides pivot abutments 138A, 138B and a stem 116 for the rocker and which is snap fitted to the rocker body 110. <IMAGE>

Description

Title: Rocker-switched Electrical Accessories DESCRIPQION The invention relates to switched electrical accessories and has particular reference to rocker type switch means.

Conventionally, electrical rocker type switches as used in connection with electrical mains circuits comprise a switch plate for fixing to accessory boxes, the switch plate carrying a switch mechanism at its rear and the operating rocker protruding through or from a well formation in its front. A typical rocker is operative on the switch mechanism to move one contact into and out of electrical connection with at least one fixed contact, a- comprises a generally T-shaped member operated pizo;ally via its head or cross-piece and having a hollof stem housing a spring-loaded plunger as actuator for the moving contact.Pivotting is conveniently at rocker retaining engagement of side abutments integral with the rocker, usually its stem, in V-shaped grooves in sides of the switch plate flanking the aperture for the rocker head, and it is generally considered to be advantageous for the rocker to be of different plastics material from the switch plate.

Such abutments rigid on the rocker stem lead naturally to assembly of the rocker and other switch parts entirely from the rear of the switch plate and to a resulting switch from which the rocker will fall out if other switch parts are rewired, whereas abutments on resilient side leaves of the rocker permit fitting of a complete rocker assembly from the front of the switch plate into a flash-masking well and results in a switch where it is difficult is not impossible to remove the rocker.

It is an object of this invention to provide a relatively advantageous rocker and/or completed sic and/or assembly procedure.

According to one aspect of this invention, a rocker has a separate member associatable therewith and providing its pivot abutments or mechanical equivalent.

The separate member according to one embodiment preferably engages a stem of the rocker, the rocker being generally T-shaped, and/or the switch plate (or its mechanical equivalent) in a manner then retaining the rocker.

Tn an alternative embodiment, the separate member constitutes, in effect, the stem of the rocker and engages a body of the rocker and/or the switch plate (or its mechanical equivalent) in a manner then retaining the rocker. Such engagement can involve resilience of a part or parts of the separate member.

There is an immediate advantage in that only the material of the separate member need be chosen for its resilience and/or suitability for pivot abutments. If desired, the rocker itself may be of the same material as the switch plate (or its mechanical equivalent) and thus avoid difficulties of matching colours and surface finishes.

For a switch plate (or mechanical equivalent) having under the rocker head a well open only for the rocker stem, i.e. where the rocker must be inserted from the front, the separate member according to one embodiment can be inserted from the rear over the rocker stem and, according to another embodiment, can be inserted from the rear into cooperating engagement with the rocker body. As a separate member that completely is inserted from the rear, for example so as to encircle the rocker stem, that part can lead to the further advantage that even the clearance of the rocker where it passes through the switch plate, e.g. the stem, can thereby be masked from showing electrical flash at contact operation.

Another advantage attainable from using such separate members is that they can readily be made easy to disengage and thus aid disassembly of the rocker from the switch plate (or mechanical equivalent) Practical implementation of the invention will now be described, by way of example, with reference to the accompanyin.g diagrammatic drawings, in which: Figure 1 is a partial section through an installed rocker and separate member hereof; Figures 2 and 3 are side and transverse (relative to Figure 1) sectional views of the rocker; Figures 4, 5 and 6 are plan and orthogonal side views of the separate member; Figures 7, 8 and 9 are front plan, rear plan and sectional views of a switch plate; Figures 10 and 11 are perspective views of the separate member and rocker of a first embodiment illustrated in Figures 1 to 5; and Figures 12 and 13 are perspective views of the separate member and rocker body according to a second embodiment.

In the drawings, especially Figures 1 to 9 a rocker 10 is of generally T-shape with a head 12 for finger engagement to operate the rocker by its arcuate outer surface 14 and a stem 16 that has a blind bore 18 from its free end 20 to house a spring-loaded plunger (not shon whose tip will extend beyond its end 20. It is intended that the rocker stem 16 be a clearance fit through an aperture 22, see also for switch plate 24 of Figure 7, past sides ledges serving as pivot locations, see also 26A and 263 in Figure 7 and top edges 28A, 28B of grooves 29A, 29B in Figure 8.

Associated or for association with the rocker 10 is a separate member 30 having a central aperture 32 in a top part 34 from opposite sides of which depend two side legs 36A and 36B carrying exteriorly projecting therefrom two abutment parts or ribs 38A and 383, respectively, each sho as narrower than the associated leg and effectively extending the length of that leg to a substantial extent in affording free ends 40A and 40B, respectively. Tops 42A, 42B of the parts 38A, 38B provide pivot abutments for the edges 28A, 283 of the grooves 29, 29B of Figure 9. The aperture 32 fits about the rocker stem 16.The legs 36A, 363 and ribs 38S, 383 are resilient and teeth 44A, 44B extending inwardly of the legs 36A, 36B serve latchingly to associate the separate member 30 with the rocker stem 16 by engaging into indentations 46A, 463 therein.

Chamfering of the trailing edges 48t, 483 of the teeth ensure that the top 34 of the separate member 30 is pressed against the underside of the rocker 10 and/ or the tops 42A, 423 of the ribs 38A, 38B are pressed against the tops 28A, 283 of the grooves 29A, 29B. The same effect could be achieved by appropriate chamfering of corners of bottom edges 50A, 50B of the recesses 46A, 463. Retention of the rocker 10 in a carrier such as the switch plate 24 is, of course, then assured via ledges 26A, 263 and tops 42A, 423 of the ribs 38A, 383 of the separate mercer 30.

It will be noted that undersides 54A, 54B of the rocker head 12 are cut back to define a shallow V-shape, also that correspor surfaces 26A, 26B of a well 58 from which aperture 22 is cut on the switch plate of Figures 7 to 9 are yet :2ore steeply ramDed so as to afford the required pivotal operating movement of the rocker 10. The aperture 22 is bounded by opposite side walls which form side wells 56A, 563 in the well 58.

Assembly of the rocker 10 into a carrier such as the switch plate 24 is achieved readily by placing the rocker 10, head don, in a nest, placing the switch plate thereover so that the rocker stem 16 goes through the switch plate aperture 22, then pushing the separate member 30 into place over the rocker stem 16. It does not matter whether the spring loaded plunger is installed in the rocker stem before or after such assembly of rocker 10 to the switch plate 24. Other parts of the switch, i.e. fixed contacts moving contact and rear cover are then readily emplaced in the rearward housing 60 of the switch plate 24.More detail on the latter stages of assembly are available in our copending application no. 8501378 (P1436), and, for the purpose hereof, we note only that two stationary contact members 62, 64 with associated terminals are shown in Figure 8 together with a moving contact assembly 66 with associated terminal, for two-way switching action, and that a cover can be installed by screws or rivets in holes 68A, 683.

It will be evident how the described and illustrated implementation satisfies features and advantages of the invention mentioned previously. For example disassembly of the rocker 10 and separate part 30 can be simply done if the free ends 40A, 403 of the ribs 38A, 38B can be engaged and forced apart.

Referring now to Figures 12 and 13, there is illustrated another embodiment of rocker assembly according to the invention. A rocker for an electrical rocker type switch comprises a body 110 and a separate member 130 providing pivot abutments for the rocker.

The rocker body 110 has an arcuate outer surface 114 with side walls extending therefrom to define a well for receiving the separate member 130. Opposite side walls 111AS 1113 are cut back defining under sides 54A, 543 which in use are associated with romped surfaces such as 26A, 263 of the switch plate to afford the required pivotal operating movement of the rocker. Disposed on the inner faces of the side walls 111A, 1113 are latch members which in the illustration take the form of respective pairs of abutments 113 with a wedge/ramp face 115. The latch members are cooperable with resilient teeth members 144 of the separate member, for retaining engagement of the separate member 130 with the rocker body 110.

Turning now to the construction of the separate member, this comprises a generally T-shaped member, having a head part 117 and a stem part 116. The stem part 116 has a blind bore 118 therein for receiving a spring loaded plunger for operating switch contacts in a manner similar to that described previously. The head part 117 is adapted to fit within the rocker body 110 and, as mentioned, is provided with pairs of latching teeth members 144A, 1443 on opposite sides of the head parts for cooperating engagement with latching abutments 113 of the rocker body. The latching teeth members are disposed on the end of resilient legs 136 extending from the sides of the head part. The free ends of the legs being chamfered/ tapered for ease of introduction into cooperating engagement with the latch members.

The head part 117 is dimensioned to pass through an aperture of the switch plate well 38, whilst, the rocker head with which it cooperates is larger than the aperture and received within the well 38 with clearance.

Projecting from opposite sides of the separate member and preferably braced with respect to the stem part are abutment parts 138A, 1383; preferably having an arcuate top surface 142 as illustrated. The said top surface provides pivot abutments with grooves, as 28 say, of the switch plate to facilitate pivotal movement of the rocker for operation of switch contacts when assembled in an electrical accessory. The rocker body is positioned at the front of the switch plate in an apertured rocker receiving well, and the separate member is fitted from the rear to unite the rocker body and separate member and form a rocker assembly in pivotal retaining engagement with the switch plate or its mechanical equivalent. Thus, the separate member 130 is inserted into the rocker body 110, in a snap-fitting manner to form a rocker assembly, which snap-fitting also serves to locate the assembly in a switch plate or its mechanical equivalent such as that illustrated in Figures 7, 8and9.

The latter embodiment has the advantage of allowing different materials to be employed for the rocker body and pivot abutments and is also advantageous in avoiding sink marks in showing through the outer surface of the rocker body.

Claims

1. A rocker for a switched electrical accessory the rocker comprising a rocker body and a separate member associatable with the rocker body to provide therefor the pivot abutments and wherein the separate member constitutes in effect a stem of the rocker and engages cooperatingly the rocker body with resilience in a snap fitting manner.

2. A rocker as claimed in claim 1 in which the rocker body comprises a head and wherein the separate member comprises a part which is received in the head and which has oppositely disposed legs each presenting exteriorly a tooth which engages the head, a stem part of the separate member having exteriorly opposite faces providing the pivot abutment.

3. A rocker as claimed in claim 2 in which the head is received in a well in the front face of the switch plate and said part of the separate member passes through an aperture in said well to allow fitting of the separate member from the rear of the switch plate into retaining engagement with the rocker body.

4. A rocker as claimed in claim 2 or 3 in which the oppositely disposed legs are in two pairs on opposite sides of the part with respective teeth for cooperating engagement with respective latch members of the rocker head.

5. A rocker as claimed in any one of claims 2 to 4 in which the engagement involves resilience of a part or parts of the separate member.

6. A rocker as claimed in claim 5 in which the resilient parts are the legs.

7. A rocker as claimed in claim 2 or any claim appendent thereto in which the stem part has an axial bore therein open at the free end of the stem part for receiving a spring loaded plunger.

8. A rocker as claimed in claim 3 or any claim appendent thereto in which the well has opposite side surfaces which are ramped so as to afford the required pivotal operating movement of the rocker.

9. A rocker as claimed in claim 8 in which the under side of the head of the rocker is cutback for allowing pivotal operating movement of the rocker in the switch plate well.

10. A rocker constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings of Figures 12 and 13.

11. A switch for an electrical accessory, the switch comprising a switch plate, a rocker for operating switch contacts and having a head received in a well of the switch plate, and a separate member associatable with the rocker and the switch plate to provide the pivot abutment for the rocker by engagement with the switch plate and wherein the separate member constitutes in effect a stem of the rocker and engages cooperatingly the head with resilience in a snap fitting manner.

12. A switch as claimed in claim 11 in which the separate member has a part which is received in the head, which part passes through an aperture in the well of the switch plate from the rear thereof and has resilient toothed legs engageable with latch members on the head, and a stem part of the separate member having exteriorly opposite faces providing the pivot abutment and engageable with abutment surfaces on the under side of the switch plate.

13. A switch constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings of Figures 7, 8, 9, 12 and 13.