Touch switching system

• US 4,939,428 A
• Filed: 01/26/1988
• Issued: 07/03/1990
• Est. Priority Date: 01/26/1988
• Status: Expired due to Term

• Current Assignee: Heller Financial Incorporated (General Electric Company)
• Original Assignee: Westek Associates
• Inventors: DePauli, John F.
• Primary Examiner(s): LaRoche, Eugene R.
• Assistant Examiner(s): Neyzari, Ali
• Application Number:
  US07/148,767
• Time in Patent Office: 889 Days
• Field of Search: 307/116, 307/114, 315/74, 315/291, 315/194, 315/199, 315/DIG. 4, 315/362, 200/5 A, 200/292, 200/512
• US Class Current: 315/291
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/703 characterised by spacers between contact carrying layers
• CPC Class Codes: H01H 2207/018 Spacer elements
• CPC Class Codes: H01H 2211/004 Adhesive
• CPC Class Codes: H01H 2211/028 Contacts in depressions of layers
• CPC Class Codes: H01H 2213/002 with external pressure
• CPC Class Codes: H01H 2227/01 Adhesive
• CPC Class Codes: H01H 2231/00 Applications
• CPC Class Codes: H01H 2231/052 Selectors, e.g. dimmers
• CPC Class Codes: H05B 39/085 by touch control
• CPC Class Codes: H05B 47/10 Controlling the light source
• CPC Class Codes: Y10S 315/04 Dimming circuit for fluorescent lamps

Abstract

The described embodiment of the present invention provides a very low pressure electrical switch for use in brightness control of lamps. The electrical switch includes a flexible membrane on which printed leads are interlaced in a regular fashion. Portions of the interlaced electrical leads are exposed. The membrane is fastened to the surface of a rigid surface. In the area under the exposed conductor, a fixed conductor is formed. The membrane is fastened to the surface of the rigid surface so that a very small spacing is maintained between the exposed conductors and the fixed conductor. Because of this small spacing, a very light touch is required to cause the exposed conductors to be shorted to the fixed conductor. A microprocessor then determines which leads of the membranes are shorted together and causes the light to dim appropriately. The lighting system also contains a delay off feature in which the microprocessor causes a discernible dimming to occur when the delay off feature switch is pressed but which does not shut off the lamp until a fixed period of time has passed, thereby allowing the operator to leave the room completely before the lamp is shut off.

Claims

1. A low pressure electrical switch comprising:

a flexible membrane;

a plurality of spaced apart electrical pattern conductors disposed in a continuous single column array upon a first surface of said membrane;

a plurality of electrically conductive range leads disposed upon said membrane, each range lead coupled to alternate ones of said pattern conductors in a respective region of said conductor array;

a plurality of electrically conductive level leads disposed upon said membrane, each level lead coupled to a respective other one of said conductors in each respective region of said conductor array;

a rigid member having a flat surface, a recessed portion of said rigid member surface aligned and facing said conductor array; and

a fixed conductor formed in said recessed portion, said membrane being attached to said rigid member with said conductor array suspended over said recessed portion so that certain ones of said pattern conductors come in contact with said fixed conductor when pressure is applied to a second surface of said membrane above said recessed portion.

2. A low pressure electrical switch as in claim 1 wherein said flexible membrane comprises a mylar membrane.

3. A low pressure electrical switch as in claim 1 further comprising a spacer placed between said flexible membrane and said rigid member providing precise spacing between said pattern conductor and said fixed conductors.

4. A low pressure electrical switch as in claim 1 wherein said fixed conductor is formed by depositing a carbon conductor in said recessed portion.

5. The low pressure electrical switch of claim 1 further comprising a spacer layer disposed between said rigid member and said membrane, said spacer layer having an open portion aligned with said conductor array and said fixed conductor.

6. A low pressure electrical switch comprising:

a flexible membrane;

a plurality of parallel spaced apart straight electrically conductive segments aligned in a continuous single column linear array on a lower surface of said membrane;

a plurality of electrically conductive range leads disposed upon said membrane, each range lead coupled to alternate ones of said conductive segments in a respective adjacent region of said array;

a plurality of electrically conductive level leads disposed upon said membrane, each range lead coupled to a respective other one of said conductive segments in each respective adjacent region of said array;

a rigid member coupled to said membrane, said rigid member having an upper surface facing said membrane lower surface;

a spacer layer disposed between said rigid member and said membrane, said spacer layer having an open portion aligned with said array; and

a fixed conductor formed on said rigid member upper surface and aligned with said spacer layer opening, said array suspended over said fixed conductor so that certain conductive segments come in contact with said fixed conductor when pressure is applied to an upper surface of said membrane above said array.

7. A low pressure electrical switch as in claim 6 wherein said flexible membrane comprises a mylar membrane.

8. A low pressure electrical switch as in claim 6 wherein said fixed conductor is formed by depositing a carbon conductor in alignment with said opening of said spacer layer.

9. A low pressure electrical switch as in claim 6 wherein said spacer layer comprises adhesive material.