Patent US3573806A successfully refreshed from Google Patents.
US3573806A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noncontact encoder interpolation technique
Assignee: Individual
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Filing: 1968-09-30
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Granted: 1971-04-06
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Expires: 1988-09-30
Abstract
Abstract This invention is directed to an optical shaft encoder. The encoder utilizes a binary coded disc whose last track is clear. The output of the photodetector associated with this track is compared by appropriate circuitry with the output of two matched detectors each having an area half that of the first detector. This comparison yields a signal which is an angular function of the position of the disc. A decimal to binary converter is utilized to provide a binary representation of the comparison signal.
Inventors
- 👤 Aaron David Klein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:13
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/22
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
130 words
An analogue to digital encoder, comprising: a disc mounted on a shaft, the angular position of which is to be expressed in digital form; said disc having a plurality of circumferentially extending tracks; the outermost track on said disc being completely transparent and the remaining inner tracks on said disc each having transparent and opaque segments, said tracks forming a digital code for representing angular position; a source of energy mounted adjacent to said disc; a plurality of detectors mounted on the side of the disc opposite that on which the source of energy is mounted wherein at least one detector is provided for each track with two detectors being provided for the outermost segmented track; and electrical means connected to said detectors for providing a representation of their outputs.
Claim 2
Dependent Claim
130 words
An analogue to digital encoder, comprising: a disc mounted on a shaft, the angular position of which is to be expressed in digital form; said disc having a plurality of circumferentially extending tracks; the outermost track on said disc being completely transparent and the remaining inner tracks on said disc each having transparent and opaque segments, said tracks forming a digital code for representing angular position; a source of energy mounted adjacent to said disc; a plurality of detectors mounted on the side of the disc opposite that on which the source of energy is mounted wherein at least one detector is provided for each track with two detectors being provided for the outermost segmented track; and electrical means connected to said detectors for providing a representation of their outputs.
Claim 3
Dependent Claim
71 words
An analogue to digital encoder as in claim 1, wherein said electrical means comprises: first means for giving a representation of the angular position expressed by the tracks on said disc other than said outermost segmented track; and second means for giving an electrical representation of the angular position expressed by said outermost segmented track which represents the smallest angular division in the code formed by the tracks of said disc.
Claim 4
Dependent Claim
89 words
An analogue to digital encoder as in claim 2, wherein said second means includes: an adder circuit to sum the outputs of the two detectors associated with said outermost segmented track which represents the smallest angular division in the code formed by the tracks of said disc; and a divider circuit to receive the output associated with said outermost transparent track and the output of said adder circuit; and said divider circuit being operative to divide the output of said two detectors by the output of said adder circuit.
Claim 5
Dependent Claim
28 words
An analogue to digital encoder as in claim 3 wherein said second means further includes a decimal to binary converter connected to the output of said divider circuit.
Claim 6
Dependent Claim
99 words
An analogue to digital encoder as in claim 4 wherein said decimal to binary converter has a plurality of stages each of which comprises: a flip-flop; a multiplier which multiplies the received signal by decreasing powers of 1/2n 1 a subtractor which subtracts decreasing powers of 2n 1 from the input signal; a reference signal means; a comparator which compares the output of said multiplier with A signal from said reference signal means; and said comparator being operative to trigger said flip-flop and said subtractor when the output of said multiplier exceeds the signal from said reference signal means.
Claim 7
Dependent Claim
20 words
An analogue to digital encoder as in claim 3 wherein the tracks of said disc utilize a binary coding system.
Claim 8
Dependent Claim
24 words
An analogue to digital encoder as in claim 6 wherein the source of energy is a light source and the detectors comprise photoelectric detectors.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-05 | 1974-10-05 | 1975-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-05 | 1978-10-05 | 1979-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-05 | 1982-10-05 | 1983-04-06 | $7700.00 | Window Closed / Lapsed |