US3567951A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser projectile detection system
Assignee: United States Department of the Navy
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Filing: 1969-04-14
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Granted: 1971-03-02
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Expires: 1989-04-14
Abstract
Abstract The present invention is directed to a system which measures the ejection time and muzzle velocity of a gun. The system utilizes a laser whose beam is split and then directed across the projectile ejection path to two photodetectors. When the gun is triggered, a projectile is fired and a first counter is activated. When the projectile leaves the gun barrel it breaks the first light path between the laser and the first photodetector and turns off the first counter. Simultaneously, it initiates a second counter which is deactivated when the light path to the second photodetector is broken by the projectile.
Inventors
- 👤 Hugh E Montgomery Jr
- 👤 Conrad W Brandts
- 👤 Richard A Frazer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:21
CPC Classifications
G; G04; G04F; G04F10/00; G04F10/04; G01; G01P; G01P3/00; G01P3/64; G01P3/68; G01P3/685
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
196 words
A system for measuring the muzzle velocity of a gun comprising: a source of coherent light mounted adjacent to the muzzle of said gun and operative to direct a first and second beam of coherent light across the projectile path of said gun; a first photodiode, a first direct current source and a first adjustable impedance connected in series; a second photodiode, a second direct current source and a second adjustable impedance connected in series; said first photodiode being operative to receive said first beam of coherent light and said second photodiode being operative to receive said second beam of coherent light; filtering means mounted immediately adjacent to both said photodiodes for passing only that light which has the frequency of said coherent light source; first counting means electrically connected to said first and second photodiodes for activation by the passage of a projectile, ejected from said gun, through the first beam of coherent light and deactivation by passage of the projectile through the second beam of coherent light; a first capacitor connected between said first counting means and said first photodiode; and a second capacitor connected between said first counting means and said second photodiode.
Claim 2
Independent Claim
196 words
A system for measuring the muzzle velocity of a gun comprising: a source of coherent light mounted adjacent to the muzzle of said gun and operative to direct a first and second beam of coherent light across the projectile path of said gun; a first photodiode, a first direct current source and a first adjustable impedance connected in series; a second photodiode, a second direct current source and a second adjustable impedance connected in series; said first photodiode being operative to receive said first beam of coherent light and said second photodiode being operative to receive said second beam of coherent light; filtering means mounted immediately adjacent to both said photodiodes for passing only that light which has the frequency of said coherent light source; first counting means electrically connected to said first and second photodiodes for activation by the passage of a projectile, ejected from said gun, through the first beam of coherent light and deactivation by passage of the projectile through the second beam of coherent light; a first capacitor connected between said first counting means and said first photodiode; and a second capacitor connected between said first counting means and said second photodiode.
Claim 3
Dependent Claim
74 words
A system as in claim 1 wherein said source of coherent light comprises: a laser for generating coherent light; a beam splitter mounted to receive the coherent light generated by said laser; a reflecting mirror mounted adjacent to said beam splitter; and said beam splitter being operative to divide the generated coherent light and to pass said first beam of coherent light and to reflect said second beam of coherent light to said mirror.
Claim 4
Dependent Claim
34 words
A system as in claim 2 further comprising second counting means connected to said first capacitor, whereby the output of said second counting means provides a measure of the ejection time of said gun.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-01 | 1974-08-31 | 1975-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-01 | 1978-08-31 | 1979-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-01 | 1982-08-31 | 1983-03-02 | $7700.00 | Window Closed / Lapsed |