US3838291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detector indicating availability and position of tape
Assignee: FIELDSTON ACQUISITION Inc
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Filing: 1973-05-17
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Granted: 1974-09-24
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Expires: 1993-05-17
Abstract
Abstract A tape detector operates inside an information recording and retrieving system structure. In the detector, a lense-equipped light source located inside a housing produces three beams of light which, after crossing above, below, and through an ordinary commercial recording tape, pass through an optical prism where they are deflected back toward the light source housing. On their return, the light beams again cross above, below, and through the tape and then converge on the surfaces of three photodetectors arranged in a vertical line in the same housing as and adjacent to the light source. Signals from the photodetectors indicate the following: the upper photodetectors signal whether the tape is available for recording, the middle one signals a particular position of the tape such as the beginning or the end of the tape, and the lower one signals the presence or absence of a tape cartridge within the system structure.
Inventors
- 👤 A Marion
- 👤 G Kaposhilin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:36
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/02; G11B15/16; G11B15/05; G11B15/06; G11B15/08
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
135 words
An electro-optical detector for use with a tape in a tape transport mechanism, the detector comprising: a light source supported in the transport mechanism for generating a light beam; a plurality of photodetectors supported in the transport mechanism; and an optical reflector disposed in front of the light source for reflecting the light beam from the light source to the photodetectors, a first portion of the light beam passing from the light source to a photodetector through a hole provided in the tape for detecting a first condition, a second portion of the light beam passing from the light source to a photodetector above the tape for detecting a second condition and a third portion of the light beam passing from the light source to a photodetector below the tape for detecting a third condition.
Claim 2
Dependent Claim
135 words
An electro-optical detector for use with a tape in a tape transport mechanism, the detector comprising: a light source supported in the transport mechanism for generating a light beam; a plurality of photodetectors supported in the transport mechanism; and an optical reflector disposed in front of the light source for reflecting the light beam from the light source to the photodetectors, a first portion of the light beam passing from the light source to a photodetector through a hole provided in the tape for detecting a first condition, a second portion of the light beam passing from the light source to a photodetector above the tape for detecting a second condition and a third portion of the light beam passing from the light source to a photodetector below the tape for detecting a third condition.
Claim 3
Dependent Claim
67 words
An electro-optical detector as in claim 1 wherein there is a housing mounted in the transport mechanism for supporting the light source and the photodetectors; and there are three photodetectors disposed on a vertical line on a face of the housing, each receiving a different portion of the light beam and wherein the source is in the middle of and to one side of the photodetector line.
Claim 4
Dependent Claim
31 words
An electro-optical detector as in claim 2 wherein the light source side of the housing face has a lens for splitting the light rays from the source into three light beams.
Claim 5
Dependent Claim
48 words
An electro-optical detector as in claim 3 wherein the tape has a first and second hole and the optical reflector is a prism which has a collimating lens located to receive the first portion of the light beam passing through the first of the holes in the tape.
Claim 6
Dependent Claim
44 words
An electro-optical detector as in claim 4 wherein the prism has three exit lenses disposed in a vertical straight line, the middle lens being located to receive the first portion of the light beam passing through the second of the holes in the tape.
Claim 7
Dependent Claim
21 words
An electro-optical detector as in claim 5 wherein the light source is a light emitting diode powered by a pulsating source.
Claim 8
Dependent Claim
48 words
An electro-optical detector as in claim 5 wherein the tape is contained in a cartridge and the prism and the lenses in the prism are molded into a cartridge cover, the prism being located near a wall of the cartridge which faces the light source and the photodetectors.
Claim 9
Dependent Claim
46 words
An electro-optical detector as in claim 6 wherein a shutter is mounted on the cartridge wall between the prism and the housing, the shutter being movable into a predetermined position for blocking the passage of one of the second and third portions of the light beam.
Claim 10
Dependent Claim
40 words
An electro-optical detector as in claim 1 wherein the first condition is a predetermined point along the length of the tape, and one of the second and third conditions is the presence of the tape in the tape transport mechanism.
Claim 11
Dependent Claim
73 words
An electro-optical detector as in claim 9 wherein the tape is contained in a cartridge, a movable shutter is mounted on a wall of the cartridge adjacent the photodetectors for blocking one of the second and third portions of the light beam, and the other of the second and third conditions is the presence of the shutter in the path of said one of the second and third portions of the light beam.
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) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |