Pressure sensitive matrix switch having apertured spacer with flexible double sided adhesive intermediate and channels optionally interposed between apertures

• US 4,065,649 A
• Filed: 06/14/1976
• Issued: 12/27/1977
• Est. Priority Date: 06/30/1975
• Status: Expired due to Term

• Current Assignee: Guy F Atkinson Company
• Original Assignee: Lake Center Industries, Inc. (Northrop Grumman Corporation)
• Inventors: Carter, Everett M., Quain, Wilbur C.
• Primary Examiner(s): Scott, James R.
• Application Number:
  US05/695,968
• Time in Patent Office: 561 Days
• Field of Search: 200/5 R, 200/5 A, 200/159 B, 200/264, 200/265, 200/262, 200/292, 200/302, 200/340, 200/86 R, 200/239
• US Class Current: 200/5.00A
• 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 2203/02 Interspersed fingers
• CPC Class Codes: H01H 2209/018 flat, smooth or ripple-free
• CPC Class Codes: H01H 2209/03 elastomeric
• CPC Class Codes: H01H 2209/052 elastomeric
• CPC Class Codes: H01H 2209/074 elastomeric
• CPC Class Codes: H01H 2211/004 Adhesive
• CPC Class Codes: H01H 2213/01 with internal pressure of other switch sites
• CPC Class Codes: H01H 2229/004 Conductive ink
• CPC Class Codes: H01H 2229/028 Adhesive
• CPC Class Codes: H01H 2231/026 Car
• CPC Class Codes: H01H 2231/05 Card, e.g. credit card

Abstract

This is concerned with a switch device which is quite thin and can be used on either a flat or a contoured surface that includes a backing member which may be dimensionally stable, either as a flexible or a stiff membrane, with a flexible membrane spaced therefrom by a flexible filled adhesive material providing one or more openings so that a circuit pattern on the backing member is spaced from a conductive shorting bar on the flexible membrane such that manual or mechanical deformation of the membrane will cause electrical conduction across or between the contacted surface in the circuit pattern with deformation being provided by the flexibility of the membrane, as well as deflection or flexing of the intermediate adhesive material.

Claims

1. In a switch control device, a backing layer with a printed circuit having switch conductors on the upper surface thereof defining at least one switch contact area, a flexible adhesive insulating layer adhering to the upper surface of the backing layer with at least one opening around the switch contact area, and a flexible contact layer adhering to the upper surface of the adhesive insulating layer and overlying the opening with a conductive shorting bar on the lower surface thereof aligned with the opening over the contact area, the flexibility and thickness of the adhesive insulating layer causing it to participate in the deformation of the contact layer to allow for contact of the shorting bar with the switch contact area without elongation of the contact layer when the contact layer is pressed toward the backing layer in the area aligned with the opening in the flexible adhesive insulating layer and causing spring return of the contact layer when such pressure is released, the adhesive insulating layer adhering to the upper surface of the backing layer and the lower surface of the contact layer to structurally retain the dimensional stability of the switch control device.

2. The structure of claim 1 further characterized in that the flexible contact layer is made of Mylar and is on the order of 0.010 inches (0.25 mm.) in thickness.

3. The structure of claim 1 further characterized by and including a thin reinforcing sheet disposed in the flexible adhesive insulating layer intermediate and generally parallel to the backing and flexible contact layer.

4. The structure of claim 1 further characterized in that the backing layer is flexible.

5. The structure of claim 1 further characterized in that the lower surface of the flexible contact layer is decorated.

6. The structure of claim 1 further characterized in that the adhesive insulating layer adheres both to the lower surface of the contact layer and the upper surface of the backing layer so as to hermetically seal the opening with the switch contact area and shorting bars.

7. The structure of claim 1 further characterized in that the conductive shorting bar on the lower surface of the flexible contact layer is in the form of silver epoxy paint.

8. The structure of claim 1 further characterized in that the backing layer is rigid.

9. The structure of claim 1 further characterized by and including two switch contact areas, and a channel in the insulating layer interconnecting the two contact areas so that a pumping action may occur between the two areas when the contact layer is pressed toward the backing layer in the area aligned with one opening causing air to be pumped through the channel into the other area.