Rotary switch with reflector coded actuator drum

• US 4,634,861 A
• Filed: 12/19/1984
• Issued: 01/06/1987
• Est. Priority Date: 12/19/1984
• Status: Expired due to Term

• Current Assignee: QT Optoelectronics
• Original Assignee: General Instrument Corporation (CommScope Holding Company, Inc.)
• Inventors: Merchant, Adnan, Babbitt, Frank B. Jr., Ching, Stephen
• Primary Examiner(s): LaRoche, Eugene R.
• Assistant Examiner(s): Mottola, Steven J.
• Application Number:
  US06/683,600
• Time in Patent Office: 748 Days
• Field of Search: 250/229, 250/231 SE, 250/237 G, 250/231 GY, 250/221, 340/365 P
• US Class Current: 250/231.18
• CPC Class Codes: G01D 5/34792 with only digital scales or both digital and incremental scales
• CPC Class Codes: H03K 2217/94063 with optical detection

Abstract

A multi-position rotary switch comprises an actuator drum divided into a plurality of different n-bit codes where each bit is represented by a reflective area or a non-reflective area on the drum. The drum is radiated by a suitable emitter and radiation reflected off of the drum by reflective bits is detected by a plurality of radiation detectors. The drum is rotatable to bring the different n-bit codes into view of the radiation detectors. Each different n-bit code detected by the radiation detectors is indicative of a particular switch position.

Claims

1. A multi-position rotary switch comprising:

an actuator drum divided into a plurality of different n-bit codes where each bit is represented by a reflective area of a non-reflective area on the drum;

a plurality of emitter-detector pairs each including an emitter means for providing radiation; and

detector means for reading the n-bit codes by detecting said radiation reflected off the reflective area of said drum, said pairs each arranged to emit radiation to and detect radiation from a different bit in the n-bit codes;

a circuit board positioned adjacent to said drum with said emitter-detector pairs facing said drum and longitudinally arranged to correspond to said longitudinal strips;

means for rotating said drum to successively bring the different n-bit codes into view of said radiation detector means;

whereby each different n-bit code detected by said radiation detector means is indicative of a particular switch position.

2. The switch of claim 1 further comprising detent means for successively stopping said drum in position for said radiation detector means to read successive n-bit codes as the drum is rotated.

3. The switch of claim 1 further comprising:

a housing containing said drum, emitter means, and detector means; and

shaft means coupled to said drum and extending through said housing for use in rotating the drum.

4. The switch of claim 1 wherein said circuit board further comprises mask means having a plurality of two-port openings, said mask means fixed to said circuit board in registration with each of said emitter-detector pairs for orienting the radiation emitted and detected by each emitter-detector pair.

5. The switch of claim 1 wherein said emitter-detector pairs are configured on said circuit board to be substantially coplanar.