Touch sensitive actuator having a uniform actuation force and a maximum active area

• US 20080309169A1
• Filed: 08/27/2008
• Published: 12/18/2008
• Est. Priority Date: 06/20/2006
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Altonen, Gregory, Spira, Joel S.
• Granted Patent: US 7,566,996 B2
• Time in Patent Office: Days
• US Class Current: 307/119
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: H03K 17/96 Touch switches specially adapted for electronic time-pieces with no moving parts G04G21/08
• CPC Class Codes: H05B 47/10 Controlling the light source
• CPC Class Codes: H05B 47/165 following a pre-assigned programmed sequence; Logic control [LC]
• CPC Class Codes: H05B 47/17 Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations

Abstract

A load control device for controlling the amount of power delivered to an electrical load from an AC power source comprises a touch sensitive device having a touch sensitive front surface responsive to a point actuation. The front surface is adapted to be provided in an opening of a faceplate such that the front surface of the touch sensitive actuator extends through the opening at a distance equal to or greater than the depth of the faceplate. According to the present invention, the operational area of the front surface is maximized to substantially the entire area of the front surface. Further, a minimum magnitude of a force of each of the point actuations is substantially equal at each of the respective positions on the front surface of the touch sensitive actuator, such that the front surface provides a substantially uniform force profile.

Claims

1. A user interface for a load control device, the user interface being adapted to be positioned in an opening of a faceplate, the user interface comprising:

a touch sensitive front surface and adapted to be provided in the opening of the faceplate; and

a touch sensitive device, responsive to a point actuation on the touch sensitive front surface, the point actuation comprising characteristics of a position and a force, the touch sensitive device having an output for providing a control signal representative of the position of the point actuation;

wherein the touch sensitive device defines a first area and the touch sensitive front surface defines a second area, the first area of the touch sensitive device being larger than the second area of the touch sensitive front surface, the touch sensitive device and touch sensitive front surface being positioned such that an orthogonal projection of the second area of the touch sensitive front surface onto the first area of the touch sensitive device is encompassed by the first area.

2. The user interface of claim 1, further comprising:

an actuation member defining the touch sensitive front surface and adapted to be actuated with the point actuation, the actuation member adapted to be received in the opening of the faceplate and positioned such that the actuation member is operable to contact the touch sensitive device and to concentrate the force of the point actuation onto the touch sensitive device.

3. The user interface of claim 2, wherein the actuation member comprises a post, operable to transmit the force of the point actuation onto the touch sensitive device.

4. The user interface of claim 3, wherein the actuation member is provided along a longitudinal axis of the user interface, and the touch sensitive device extends along the longitudinal direction for substantially the length of the actuation member.

5. The user interface of claim 4, further comprising:

a plurality of status indicators located between the touch sensitive device and the actuation member.

6. The user interface of claim 5, wherein the actuation member comprises a translucent material with the actuation member operating as a light pipe for the status indicators.

7. The user interface of claim 6, further comprising:

a printed circuit board located between the touch sensitive device and the actuation member, the status indicators mounted in a linear array on the printed circuit board.

8. The user interface of claim 7, wherein the printed circuit board comprises a plurality of holes arranged along the longitudinal axis of the user interface;

and

further wherein the actuation member comprises a plurality of first posts extending in a linear array along the longitudinal axis of the user interface for substantially the length of the actuation member, the plurality of first posts being operable to extend through the plurality of holes of the printed circuit board, such that the actuation member is operable to transmit the force of the point actuation onto the touch sensitive device.

9. The user interface of claim 1, further comprising:

a bezel defining the touch sensitive front surface, the bezel adapted to extend through the opening of the faceplate; and

a force transmitter provided between the bezel and the touch sensitive device, the force transmitter operable to transmit the force of the point actuation on the touch sensitive front surface to the touch sensitive device.

10. The user interface of claim 9, wherein the force transmitter has a substantially constant force profile.

11. The user interface of claim 10, wherein the force transmitter comprises an elastomer.

12. The user interface of claim 9, wherein the touch sensitive device is provided in a first plane and the touch sensitive front surface is provided in a second plane substantially parallel with the first plane.

13. The user interface of claim 12, wherein the touch sensitive front surface is adapted to be substantially flush with the front surface of the faceplate.

14. The user interface of claim 9, further comprising:

a plurality of status indicators arranged in a linear array behind the force transmitter;

wherein the force transmitter is comprised of a transparent material such that the status indicators are operable to shine through the force transmitter and onto the touch sensitive front surface.

15. The user interface of claim 9, wherein the bezel comprises sidewalls, the force transmitter located between the sidewalls of the bezel.

16. The user interface of claim 9, wherein a total force profile of the user interface is substantially constant across the second area of the touch sensitive front surface.

17. The user interface of claim 1, wherein the force profile of the touch sensitive device is substantially constant across the orthogonal projection of the second area onto the first area.

18. The user interface of claim 1, wherein the touch sensitive device has edges, and a force, required to actuate the touch sensitive device, being substantially greater in an area near the edges;

and

wherein the area near the edges comprises the portion of the first area outside of the orthogonal projection of the second area on the first area.

19. A load control device for controlling the amount of power delivered to an electrical load from an AC power source, the load control device comprising:

a controllably conductive device operable to be coupled in series electrical connection between the source and the load, the controllably conductive device having a control input for controlling the controllably conductive device between a non-conductive state and a conductive state;

a controller operatively coupled to the control input of the controllably conductive device for controlling the controllably conductive device between the non-conductive state and the conductive state;

a touch sensitive front surface adapted to be provided in an opening of a faceplate; and

a touch sensitive device responsive to a point actuation on the touch sensitive front surface, the point actuation comprising characteristics of a position and a force, the touch sensitive device having an output operatively coupled to the controller for providing a control signal representative of the position of the point actuation;

wherein the touch sensitive device defines a first area and the touch sensitive front surface defines a second area, the first area of the touch sensitive device being larger than the second area of the touch sensitive front surface, the touch sensitive device and touch sensitive front surface being positioned such that an orthogonal projection of the second area of the touch sensitive front surface onto the first area of the touch sensitive device is encompassed by the first area.

20. A user interface for a load control device, the user interface comprising:

a bezel defining a touch sensitive front surface, the touch sensitive front surface being provided in a first plane and defining a first area, the bezel operable to extend through the opening of a faceplate, such that the touch sensitive front surface is positioned substantially coextensive with the opening of the faceplate or slightly beyond a front surface of the faceplate;

a touch sensitive device positioned in a second plane, parallel with the first plane, and defining a second area larger than the first area, the touch sensitive device responsive to a plurality of point actuations on the touch sensitive front surface, each point actuation a position and a force, the touch sensitive device having an output for providing a control signal representative of the position of the point actuation and responsive to the point actuation when the magnitude of the force of the point actuation is greater than a minimum magnitude; and

a force transmitter positioned between the bezel and the touch sensitive device and having a substantially constant force profile, the force transmitter operable to transmit the force of the point actuation, on the touch sensitive front surface, to the touch sensitive device.