AU644419B2 - Potentiometer actuator - Google Patents

Description

COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 Form COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Short Title: Int Cl: Application Number: PK0129 Lodged: 14 May 1990 Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: H.P.M. INDUSTRIES PTY LIMITED Address of Applicant: 4 Hill Street, Darlinghurst, New South Wales 2010, Australia Actual Inventor: Peter SIMON Address for Service: GRIFFITH HACK CO 71 YORK STREET SYDNEY NSW 2000 Complete Specification for the invention entitled: POTENTIOMETER ACTUATOR The following statement is a full description of this invention, including the best method of performing it known to me/us:- GH&CO REF: 04210-NJ RW/SMcL Sc0209'i& O5/c4/9 1 6465A/SMcL _1.1 2 This invention relates to an actuating mechanism for a linear slide potentiometer and, in particular, to a mechanism which is arranged to be mounted to a facia plate and to provide translational movement from a finger actuated rocker to a linear slide potentiometer. The invention has been developed for use in connection with a light dimming controller and is hereinafter described in such context, but the invention does have broader application.

A light dimming controller would normally include a triac which is gated into conduction at a desired phase angle in each half-cycle of an alternating current supply, and the phase angle of gating is varied by adjusting a potentiometer in a gating circuit associated with the triac. The potentiometer normally has a rotary slide and, thus, is adjusted by rotating a control knob which is mounted to a facia plate which carries both the potentiometer and a light switch.

The rotary control knob is considered by some to be obtrusive and the present invention is based on the concept of using a linear slide potentiometer as a way of avoiding the need for a rotary knob. The concept is advanced by employing a pivotable rocker for actuating the potentiometer, the rocker being of a type that normally is used for operating a switch.

Therefore, the present invention may be defined in broad terms as providing an actuating mechanism for use in an electric circuit. The mechanism comprises a facia plate, a linear slide potentiometer as hereinafter defined mounted to the facia plate, a pivotable rocker, means mounting the rocker to the facia plate and a finger extending, rearwardly from the rocker. The finger is formed integrally with the rocker and has a slot which is arranged to receive a slide arm of the potentiometer and to effect straight line linear movement of the arm as a consequence of pivotable movement imparted to the rocker.

The invention also provides a light dimming controller which comprises a facia plate, a rocker S:04210NJ TCI-- -3actuated on-off switch mounted to the facia plate and an electronic circuit, including a linear slide potentiometer as hereinafter defined, carried by the facia plate and arranged for gating an alternating current supply. A control rocker for adjusting the potentiometer is pivotably mounted with respect to the facia plate and includes a rearwardly extending finger.

The finger is formed integrally with the control rocker and includes a slot which is engageable with a slide arm of the potentiometer in a manner such that pivotal movement of the control rocker causes straight line linear movement to be imparted to the slide arm.

The term "linear slide potentiometer" is employed herein in the context of a potentiometer which has a slide arm which makes a straight line linear movement when wiping against a resistive track to vary the level of resistance between the end of the track and the slide arm.

A preferred embodiment of a light dimming controller which incorporates the present invention is now described with reference to the accompanying drawings in which: Figure 1 shows a front view of a facia plate to which the controller is attached, Figure 2 shows a side elevation of the arrangement shown in Figure i, with a potentiometer actuating mechanism in a first position, Figure 3 shows a view similar to that illustrated in Figure 2 but with the potentiometer actuating mechanism in a second position, Figure 4 shows a rear view of the facia plate and controller, Figure 5 shows an enlarged perspective view of the actuating mechanism removed from the facia plate, and Figure 6 shows a more enlarged side view of a rocker/finger portion of the actuating mechanism.

As illustrated, the light dimming controller comprises a facia plate 10 which is intended to be mounted to a wall opening and which includes two S:04210NJ 3a apertures 11 for receiving mounting screws. The facia plate has two openings 12 and 13 which receive finger actuated rockers 14 and 15. The rocker 14 comprises a component part of an on-off switch 16 and is projected through its opening 12 when the switch is press-fitted into a moulded recess in the rear of the facia plate.

The other rocker 15 forms a part of a potentiometer actuating mechanism which includes the rocker itself, a rearwardly projecting finger 17 which is moulded i S:04210NJ

F

4 integrally with the rocker 15 and a mount 18 for the rocker. The rocker 15 is projected through its aperture 13 when the mount 18 is press-fitted into a moulded recess in the rear of the facia plate in much the same manner as the switch 16.

A mounting plate 19 is attached to the rear of the facia plate 10 and it mounts a circuit board 20. The plate 19 has an aperture 21 which locates about the body of the switch 16 and accommodates the finger 17 which projects through the plate from the rear side of the rocker The circuit board 20 carries electric circuit components in the form of a triac and gating circuit components (not shown), and the board 20 also carries a linear slide potentiometer 22 having a slide arm 23. A radio frequency filter coil 24 (shown only in Figure 2) is also located at the rear of the switch and is wired into the circuit for the purpose of filtering high order harmonics that result from gating the triac.

The finger 17 is moulded integrally with the rocker 15 and includes a slot 25 which is sized to receive the potentiometer slide arm 23. Pivotal movement of the rocker causes linear movement to be imparted to the slide arm 23 as a consequence of the side edges of the slot 25 engaging with the slide arm.

The rocker 15 is ,rmed with oppositely projecting spigots 26 which are supported within bearings 27 in the mount 18. The spigots 26 are formed with limit stops 28 and each bearing 27 has a V-shaped projection 29 to define the limits of pivotal movement of the rocker As above mentioned, the mount 18 is secured to the rear of the facia plate 10 by being press-fitted into a recess and peripheral projections 30 are formed on the mount 18 to provide for locking of the mount in the recess.

A cover (not shown) may be secured to the rear of the facia plate to contain the various components that are mounted to the facia plate.

1196s/SMcL

Claims (9)

1. An actuating mechanism for use in an electric circuit, the mechanism comprising a facia plate, a linear slide potentiometer as hereinbefore defined mounted to the facia plate, a pivotable rocker, means mounting the rocker to the facia plate and a finger extending rearwardly from the rocker, the finger being formed integrally with the rocker and having a slot which is arranged to receive a slide arm of the potentiometer and to effect straight line linear movement of the arm as a consequence of pivotal movement imparted to the rocker.

2. The mechanism as claimed in claim 1 wherein the means mounting the rocker to the facia plate comprises a moulded mount which is arranged to be press-fitted into a moulded recess in a rear side of the facia plate.

3. The mechanism as claimed in claim 2 wherein the rocker is formed with oppositely projecting spigots which locate within bearings in the mount and wherein at least one of the spigots is formed with limit stops which function to limit the pivotal movement of the rocker.

4. The actuating mechanism as claimed in any one of claims 1 to 3 and substantially as hereinbefore described with reference to the accompanying drawings. A light dimming controller comprising a facia plate, a rocker actuated on-off switch mounted to the facia plate, an electronic circuit including a linear slide potentiometer as hereinbefore defined carried by the facia plate and arranged for gating an alternating current supply, and a control rocker for adjusting the potentiometer, the control rocker being pivotably mounted with respect to the facia plate and including a rearwardly extending finger, the finger being formed integrally with the control rocker and including a slot which is engageable with a slide arm of the potentiometer in a manner such that pivotal movement of the control rocker causes straight line linear movement to be imparted to the slide arm.

S:04210 NJ ;i 6

6. The light dimming controller as claimed in claim 5 wherein the control rocker is mounteai to the facia plate by way of a moulded mount which is arranged to be press-fitted into a moulded recess in a rear side of the facia plate, the control rocker being pivotably mounted to the mount and, thus, being pivotably mounted with respect to the facia plate when the mount is fitted to the facia plate.

7. The light dimming controller as claimed in claim 6 wherein the control rocker is formed with oppositely extending spigots which locate within bearings in the mount and wherein at least one of the spigots is formed with limit stops which function to limit the pivotal movement of the control rocker.

S8. The light dimming controller as claimed in any one of claims 5 to 7 wherein components of the electronic circuit are mounted to a circuit board which is in turn mounted to the facia plate.

9. The light dimming controller substantially as shown in the accompanying drawings and substantially as hereinbefore described with reference thereto. DATED this 5th day of April 1991. H.P.M. INDUSTRIES PTY LIMITED By their Patent Attorney GRIFFITH HACK CO. 1196S/SMcL .1