AU692133B1

AU692133B1 - Improvements in/or relating to electrical switches

Info

Publication number: AU692133B1
Application number: AU59506/98A
Authority: AU
Inventors: David Langman Cook
Original assignee: PDL Holdings Ltd
Current assignee: PDL Holdings Ltd
Priority date: 1994-09-02
Filing date: 1998-03-25
Publication date: 1998-05-28
Anticipated expiration: 2015-08-30
Also published as: NZ329903A; AU692132B1; AU3357395A; GB9608210D0; GB2297194A; WO1996008024A1; NZ264377A; AU691962B2; GB2297194B

Description

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: *o 0* on.

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S 0 S. Name of Applicant: PDL Holdings Limited Actual Inventor(s): David Langman Cook Address for Service: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: IMPROVEMENTS IN/OR RELATING TO ELECTRICAL SWITCHES Our Ref 509179 POF Code: 1358/10281 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1-

-II

-2- This invention relates to electrical switches.

BACKGROUND

Electrical switches are required to operate in a variety of environments and to enable operation by a wide range of users. By way of an example, an environment may require the switch to be exposed to water or moisture requiring for safety a specially sealed switch.. In many instances the consumers preference would be for a switch which provided a normal external appearance. An example of a special situation, would be a disabled or handicapped user requiring a larger switch rocker for the switch than would Snormally be provided.

0.0.

An object of at least a preferred embodiment of the present invention is to provide an electric switch which enables a switch unit to be associated with a mounting plate and switch rocker to accommodate different environmental or operational requirements.

2. PRESENT TNVENTION 66 66 6 Accordingly in one aspect the invention (not claimed) may broadly be said to provide an electric switch including: a mounting plate having a front and rear face; an external actuator operably mounted in said mounting plate, said external actuator being exposed and operable from said front face of said mounting plate; a control member extending from the rear of said external actuator such that movement of the external actuator causes 2 a pivotal movement of the control member; a switch unit having fixed contacts, a movable contact member with contacts to complete a contact set with the fixed contacts and an internal actuator operable to move the movable contact member to open or close an electrical circuit between the fixed contacts, the internal actuator being mounted for pivotal movement relative to the external actuator and provided with a recess having opposing sides, the control member of the external actuator being operatively engaged within the recess such that movement of the external actuator provides a positive force by the control member against one or other of the sides of the recess to effect pivotal movement of the internal actuator to open or close the contact set.

In a further aspect the invention (not claimed) may broadly be said to provide an electric switch including: a mounting plate having a front and a rear face; an external actuator -3pivotally mounted in said mounting plate, said external actuator being exposed from said front face of said mounting plate; a control member extending from the rear of the external actuator, such that pivotal movement of the external actuator causes corresponding pivotal movement of the control member; a switch unit having fixed contacts, a movable contact member and an internal actuator operable to move the movable contact member to open or close an electric circuit between the fixed contacts, the internal actuator mounted for pivotal movement relative to the external actuator and provided with a recess having opposing sides, the control member of the external actuator being operatively engaged within the recess such that pivotal movement of the external actuator provides a positive force by the control member against one or other of the sides of the recess to effect relative pivotal movement of the internal actuator to open or close the electric circuit between said fixed contacts.

In accordance with another aspect of the invention (not claimed) there is provided an electric switch including: a mounting plate having a front and a rear face; an external actuator pivotally mounted in said mounting plate, said external actuator being exposed from said front face of said mounting plate; a control member extending from the rear of the external actuator, such that pivotal movement of the external actuator causes corresponding pivotal movement of the control member; a switch unit having fixed contacts, a movable contact member and an internal actuator pivotally mounted to move the movable contact member to open or close an electric circuit between the fixed contacts, the internal actuator mounted for pivotal movement relative to the external S actuator and provided with a recess, the control member of the external actuator being operatively engaged within the recess such that pivotal movement of the external actuator S. provides a positive force to effect relative pivotal movement of the internal actuator, and wherein the movable contact member is provided with a recess and wherein the internal actuator is provided with a dependent member to operatively engage in the recess of the movable contact member such that pivotal movement of the internal actuator provides a positive force to effect relative pivotal movement of the movable contact member to open or close the electric circuit between the fixed contacts.

In accordance with a further aspect of the invention (not claimed) there is provided an electric switch including: a switch unit having contacts, a movable contact member and an actuator operable to move the movable contact member to open or close an electric circuit between the contacts, the switch unit being attached to a mounting plate, the mounting plate having a front and a rear face; a switch rocker pivotally mounted in said mounting plate, said switch rocker being exposed from said front face of the mounting -4plate; a control member extending from the rear of the switch rocker in line with the pivotal mounting for the switch rocker, the control member being operatively engaged with the actuator so that movement of the switch rocker causes the control member to move the actuator to open or close the electric circuit between said contacts; a diaphragm extending between the actuator and the switch rocker to provide a substantially waterproof barrier therebetween in a manner permitting the control member to positively engage with the actuator, wherein the diaphragmn is fixed in sealing engagement along a peripheral portion of the switch unit surrounding the actuator and wherein a raised central section of the diaphragm extends circumferentially about the control member, said central section being disposed at or adjacent the pivot line of the switch rocker.

In accordance with yet another aspect of the invention (not claimed) the invention provides an electric switch including: a switch unit having contacts, a movable contact member and an actuator operable to move the movable contact member to open or close an electric circuit between the contacts, the switch unit being attached to a mounting plate, the mounting plate having a front and a rear face; a switch rocker pivotally mounted in said mounting plate, said switch rocker being exposed from said front face of the mounting plate; a control member extending from the rear of the switch rocker in line with S" the pivotal mounting for the switch rocker, the control member being operatively engaged with the actuator so that movement of the switch rocker causes the control member to move the actuator to open or close the electric circuit between said contacts; a diaphragm extending between the actuator and the switch rocker to provide a substantially waterproof barrier therebetween in a manner permitting the control member to positively engage with the actuator, wherein the diaphragmn is fixed in sealing engagement with the underside of the mounting plate along a peripheral portion of the mounting plate surrounding the S switch rocker.

In accordance with a still further aspect of the invention there is provided an electric switch including: a mounting plate having a rear face wad a substantially planar front face; a switch rocker pivotally mounted in said mounting plate for pivotal movement between two positions, said switch rocker being exposed from said front face of said mounting plate such that in each position a respective side of the switch rocker is substantially flush with the front face of the mounting plate to present the external appearance of a normal switch; a control member extending from the rear of the switch rocker, such that pivotal movement of the rocker causes corresponding pivotal movement of the control member; a switch unit having fixed contacts, a movable contact member and an actuator operable to move the movable contact member to open or close an electric circuit between the fixed contacts, the control member of the rocker being operatively engaged with the actuator such that pivotal movement of the switch rocker causes the control member to move the actuator to open or close the electric circuit between said fixed contacts; a diaphragm extending between the actuator and the switch rocker to provide a substantially waterproof barrier to protect the switch unit in a manner such that in use, no bias is applied by the diaphragm to the control member which would adversely affect the pivotal operation of the control member to move the actuator.

DRA WNG DESCRIPTION One preferred embodiment and modifications thereof are described with reference to the accompanying drawings in which: Figure 1 is a sectional view through an electric switch according to the present invention for use as a waterproof switch; Figure 2 is a section through a switched plug unit of modified construction also incorporating the waterproof switch; Figure 3 is an exploded view showing the various components in the electrical switch according to the present invention; Figure 4 is a plan view of the switch body; 0* .i Figure 5 is a detail of one form of pivot connection in the mounting plate for the switch rocker; Figure 6 is a detail showing an alternate pivot connection for the switch rocker; Figure 7 is a detail of a larger switch rocker; Figure 8 is a rear view of the mounting plate with the switch unit attached; and Figure 9 is a perspective view partly broken away of a waterproof switch unit having a detachable cover plate.

-6- PREFERRED EMBODIMENT The electric switch according to the present invention may be applied in a number of different electrical fittings and an exemplary range of these has been included in the accompanying drawings. Figure 3 is an exploded view of the components and the present invention will be described with initial reference to Figure 3 but the drawing reference numbers for the appropriate components will also be used on the other figures.

The switch has a mounting plate 1 in which is formed an aperture 2 to receive a switch rocker 3. The switch rocker 3 is pivotally mounted in the mounting plate 1. To achieve this pivotal mounting protuberances 4 project centrally from each side of the rocker 3, with the protuberances having a V recess in the upper surface. The protuberances engage a seat 5 having a complimentary V pivot 6 at the base of an open recess 7 as shown in greater detail in figure Alternatively the pivot 6 may be located in a closed recess 8 with the protuberances 4 9e 9.

formed to engage with a force fit into the recesses 8 thus retaining the switch rocker 3 in engagement with the mounting plate 1 once fitted in place.

Movement of the switch rocker is limited by stops 9 engaging with part of the mounting plate so that the rocker moves between two defined positions for the switching action.

.9 99 s Dependant centrally from the undersurface of the rocker is a transverse control member substantially in line with the pivot projections 4. The member 10 is shaped to engage with and operate an actuator of a switch unit as will be described in greater detail here below.

The size of the switch rocker 3 can be varied. For normal use a conventional switch rocker size would be adopted but for special purposes, for example, if the switch was to be used in an environment requiring easier operation, for example, for disabled people, a larger switch rocker could be incorporated in the mounting plate and an example of the larger switch rocker is illustrated as 3a in Figure 7.

The switch rocker is designed to operate a switch unit 11. The switch unit has a switch body 12 in which are located two fixed contacts 13 and 14 with terminals 15 and 16 to allow electrical connection. A central transverse pivot 17 is also provided on which is pivotally supported a movable contact member 18. The movable contact member has -7 central projections 19 from either side which engage within locating recess 20 in the switch base. The movable contact 18 is thus pivotally mounted in the switch base and can move between two positions to effect the switching action.

An actuator 20 has a spring loaded plunger 21 which engages the top surface of the movable contact 18. The actuator 20 has projections 22 from either side thereof that engage within apertures 23 in the side of the switch body to provide a pivotal mounting.

On the top surface of the actuator 20 is a member 23 locating a central transverse recess 24 which in use is engaged by the end of the control member 10 protruding from the switch rocker 3.

The switch unit 11 has a mount 25 in which the switch unit engages. The mount 25 is screwed to the mounting plate with screws 25a so that the switch unit is held in place with S the control member of the switch rocker operatively engaged with the recess 24 of the actuator 20. The body of the switch unit 11 has retaining arms 25b so that when the body is pressed into mount 25 the arms will retain the body in place.

S. Where the switch is used in an environment requiring waterproofing a suitable waterproof membrane 26 is located between the switch mounting plate 1 and the switch unit 11. The waterproof diaphragm is shaped to ensure that there is an adequate seal about the control member 10 which protrudes through the diaphragm and with the periphery with the diaphragm sealed in engagement with the mounting plate. It is preferable to have a shaped diaphragm having a peripheral rib 27 a raised central section 28 with a central transverse slot 29 to engage about the control member 10. The configuration of the e diaphragm is such that the slot 29 is arranged so that in the normal position the diaphragm will engage the control member 10 of the rocker switch at or adjacent the pivot line of the rocker. This can be seen in Figure 1. In this way movement of the switch rocker causes minimal movement of the diaphragm thus assisting in preserving the life of the diaphragm and ensuring a long operating life of the waterproof switch. The mount 25 is arranged to ensure that there is a good peripheral seal of the diaphragm when the switch is assembled as is shown in Figure 1.

The embodiment illustrated in Figure 2 is a switched plug unit 30 the switch body 12a has essentially the same components as were described above, but the switch unit is mounted directly in the mounting plate 1 a and an escutcheon member 31 in the mounting plate which defined the aperture for the switch rocker holds the waterproof diaphragm 26a in position.

A similar configuration is illustrated in Figure 9 where a switch unit made in the same style is illustrated. The switch has a mounting plate lb over which is fitted in use a removable cover 32. The escutcheon 31 and the diaphragm 26a remain the same as illustrated in Figure 2.

The present invention provides a switch which used with the waterproof diaphragm allows the switch to pass all of the Australian, British and New Zealand standard specifications required for a waterproof switch.

It will be apparent from the foregoing that the actuator mechanism can be designed to suit any particular requirement. For example, the same operating arrangement could be preserved but the actuator significantly enlarged to provide the user with a large actuator surface. In this instance it would not be necessary to provide the sealing as is required for a waterproof embodiment of the present invention.

0* C~ The present invention allows a conventional switch module to be incorporated in a mounting plate that can either assume the appearance of a standard switch or be modified so that the switch rocker surface is of any desired size.

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Claims

1. An electric switch including: a mounting plate having a rear face and a substantially planar front face; a switch rocker pivotally mounted in said mounting plate for pivotal movement between two positions, said switch rocker being exposed from said front face of said mounting plate such that in each position a respective side of the switch rocker is substantially flush with the front face of the mounting plate to present the external appearance of a normal switch; a control member extending from the rear of the switch rocker, such that c: pivotal movement of the rocker causes corresponding pivotal movement of the control member; a switch unit having fixed contacts, a movable contact member and an actuator operable to move the movable contact member to open or close an electric circuit between the fixed contacts, the control member of the rocker being operatively engaged with the actuator such that pivotal movement of the switch 0rocker causes the control member to move the actuator to open or close the 0* 00electric circuit between said fixed contacts; a diaphragm extending between the actuator and the switch rocker to provide a substantially waterproof barrier to protect the switch unit in a manner such that in use, no bias is applied by the diaphragm to the control member which would adversely affect the pivotal operation of the control member to move the actuator.

2. The electric switch claimed in claim 1 wherein an end of the control member engages with the actuator, said end being disposed rearwardly of the pivot line of the switch rocker and wherein a central section of the diaphragm extends circumferentially about the control member, said central section being disposed at or adjacent the pivot line of the switch rocker.

3. The electric switch as claimed in claim 2 wherein said central section of the diaphragm is of reduced thickness.

4. The electric switch as claimed in any one of claims 1 to 3 wherein the diaphragm is fixed in sealing engagement along a peripheral portion of the switch unit surrounding the actuator.

The electric switch as claimed in any one of the preceding claims wherein the diaphragm is fixed in sealing engagement with the rear face of the mounting plate along a peripheral portion of the mounting plate surrounding the switch rocker.

6. The electric switch as claimed in any one of the preceding claims wherein the actuator is mounted for pivotal movement relative to the switch rocker and the actuator is provided with a recess, the control member of the switch rocker being operatively engaged within the recess such that pivotal movement of the switch rocker provides a positive force to effect relative pivotal movement of the actuator to open or close the electric circuit. *eo•

7. The electric switch as claimed in any one of the preceding claims wherein the actuator includes a shield to protect the undersurface of the diaphragm from arcing.

8. The electric switch as claimed in any one of the preceding claims wherein the control member protrudes through the diaphragm. DATED: 25th March, 1998 PHIILLIPS ORMONDE FITZPATRICK Attorneys for: PDL HOLDINGS LIMITED 0* C C C g:\1ibrary\wdh\specsU72 159atjh ABSTRACT An electric switch comprises a mounting plate having a rear face and a substantially planar front face with an aperture provided therein. A switch rocker is pivotally mounted in the aperture for pivotal movement between two positions. The switch rocker is exposed from the front face of the mounting plate such that in each position a respective side of the switch rocker is substantially flush with the front face of the mounting plate to present the external appearance of a normal switch. A control member extends "tom the rear of the switch rocker such that pivotal movement of the switch rocker causes corresponding pivotal movement of the control member The switch also includes a switch unit (11) having fixed contacts (13, 14), a movable Scontact member (18) and an actuator The actuator (20) is operable to move the movable contact member (18) to open or close an electric circuit between the fixed contacts (13, 14). The control member (10) of the switch rocker is operatively engaged with the actuator (20) such that pivotal movement of the switch rocker causes the control member (10) to move the actuator to open or close the electric circuit between the fixed contacts (13, 14). The electric switch also includes a diaphragm (26) extending between the mounting plate and the switch unit (11) to provide a substantially waterproof barrier to protect the switch unit (11) in a manner such that in use, no bias is applied by the diaphragm (26) to the control member (10) which would o adversely effect the pivotal operation of the control member (10) to move the actuator *4 0 *o S 0 I-