US4520262A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoelectric safety screen with stray source detection
Assignee: Individual
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Filing: 1983-12-06
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Granted: 1985-05-28
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Expires: 2003-12-06
Abstract
Abstract This invention relates to safety apparatus intended for use in conjunction with industrial machinery especially of a type such as presses and guillotines. The invention employs a radiant energy safety screen with the ability to detect the presence of extraneous radiation or a failure of radiant energy sources or detectors.
Inventors
- 👤 Anthony D. Denton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:34
CPC Classifications
F; F16; F16P; F16P3/00; F16P3/12; F16P3/14; F16P3/144
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
116 words
A method of detection of opaque members when within a detection space, comprising the steps of sequentially effecting a radiant energy transmission across a detection space from a plurality of spaced apart transmission sources and generating a detection observed signal when such transmission is not sufficiently detected by each of a plurality of correspondingly located and sequentially corresponding selected detection means; and interrogating said detection means at times other than when there is a selected transmission of radiant energy from said transmission source and generating a stray source signal if sufficient radiant energy is then detected, said stray source signal indicating the presence of extraneous radiation or a failure of said transmission sources or detection means.
Claim 2
Independent Claim
116 words
A method of detection of opaque members when within a detection space, comprising the steps of sequentially effecting a radiant energy transmission across a detection space from a plurality of spaced apart transmission sources and generating a detection observed signal when such transmission is not sufficiently detected by each of a plurality of correspondingly located and sequentially corresponding selected detection means; and interrogating said detection means at times other than when there is a selected transmission of radiant energy from said transmission source and generating a stray source signal if sufficient radiant energy is then detected, said stray source signal indicating the presence of extraneous radiation or a failure of said transmission sources or detection means.
Claim 3
Independent Claim
102 words
A method of detection of opaque members when within a detection space between selected transmission and detection members, the members comprising a plurality of radiant energy transmitters and receivers aligned as pairs across the detection space, comprising the steps of activating all transmitters during a selected period of time and at least one but not all during a smaller period of time within said selected period of time and interrogating corresponding receivers at least within the period of activation of each oppositely located transmitter and generating a detection observed signal if the transmitted beam is not adequately received by the corresponding receiver.
Claim 4
Independent Claim
102 words
A method of detection of opaque members when within a detection space between selected transmission and detection members, the members comprising a plurality of radiant energy transmitters and receivers aligned as pairs across the detection space, comprising the steps of activating all transmitters during a selected period of time and at least one but not all during a smaller period of time within said selected period of time and interrogating corresponding receivers at least within the period of activation of each oppositely located transmitter and generating a detection observed signal if the transmitted beam is not adequately received by the corresponding receiver.
Claim 5
Dependent Claim
110 words
Apparatus for detection of an opaque member when within a detection space, comprising a plurality of transmitters and a plurality of receivers defining therebetween a detection space, means to sequentially effect a radiant energy transmission from each of said transmitters across said detection space, means to sequentially and in correspondence to said transmitters interrogate each of said detectors, means to generate a detection observed signal when an expected transmission is not sufficiently detected by any one of the said detectors, and means to generate a stray source signal upon any of said detectors sensing the presence of extraneous radiation or upon a failure of any of said transmitters or detectors.
Claim 6
Dependent Claim
110 words
Apparatus for detection of an opaque member when within a detection space, comprising a plurality of transmitters and a plurality of receivers defining therebetween a detection space, means to sequentially effect a radiant energy transmission from each of said transmitters across said detection space, means to sequentially and in correspondence to said transmitters interrogate each of said detectors, means to generate a detection observed signal when an expected transmission is not sufficiently detected by any one of the said detectors, and means to generate a stray source signal upon any of said detectors sensing the presence of extraneous radiation or upon a failure of any of said transmitters or detectors.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-27 | 1988-11-26 | 1989-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-27 | 1992-11-26 | 1993-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-27 | 1996-11-26 | 1997-05-28 | $7700.00 | Window Closed / Lapsed |