TARGET INDICATING SYSTEM AND METHOD

• US 3,678,495 A
• Filed: 02/26/1970
• Issued: 07/18/1972
• Est. Priority Date: 02/26/1970
• Status: Expired due to Term

• Current Assignee: Roswell W. Gilbert
• Original Assignee: Roswell W. Gilbert
• Inventors: Gilbert, Roswell W.
• Primary Examiner(s): Caldwell, John W.
• Assistant Examiner(s): Slobasky, Michael
• Application Number:
  US05/014,611
• Time in Patent Office: 873 Days
• Field of Search: 340/323 273/12.2S
• US Class Current: 340/323.00R
• CPC Class Codes: F41J 5/06 Acoustic hit-indicating systems, i.e. detecting of shock waves F41J5/056 takes precedence
• CPC Class Codes: Y10S 367/906 Airborne shock-wave detection

Abstract

Transducers are spaced evenly in opposed pairs around a metal target. The transducers receive acoustic waves created by bullets striking the target and produce corresponding electrical signals. The approximate '"'"''"'"''"'"''"'"'score'"'"''"'"''"'"''"'"' of the impact (the distance from the center of the target) is determined by starting a counter with the signal from the first transducer to receive an acoustic wave, and then stopping the counter with the signal from the last transducer to receive the acoustic wave. The approximate azimuth of the impact is determined by using the transducer signals and logic circuitry to light one of twelve lamps to indicate in which of 12 sectors of a circle the impact is located.

Claims

1. A target scoring device comprising a plurality of pairs of transducers positioned symmetrically around the target with the transducers in each pair being located substantially opposite one another, means for detecting the time difference between the first receipt of an impact-created acoustic wave by any of said transducers and the receipt of said acoustic wave by the other transducer of the pair including the transducer first receiving said wave, and means for indicating a score which is a function of said time difference.

2. A device as in claim 1 in which each of said transducers produces an electrical signal in response to the receipt by it of an acoustical compression wave.

3. A device as in claim 2 in which said target is a circular metal plate with said transducers being secured to the edge of said plate equidistant from the center of said plate, there being at least three of said pairs of said transducers.

4. A device as in claim 3 in which each of said transducers is a lead zirconate titanate cell. 5. A device as in claim 1 in which said detecting means includes a counter, and means for starting the counter with the signal from the first of said transducers to receive said wave, and stopping said counter with the signal from the last of said transducers to receive said wave.

6. A device as in claim 5 including a clock signal source, circuit means for connecting said clock signal source to said counter upon the receipt of a signal from any of said transducers, and for holding said connection and then releasing said connection upon receipt of a signal from the transducer located opposite to said first transducer.

7. A device as in claim 1 including a counter, a clock signal source whose clock frequency is proportional to the time required for said wave to travel from the center to the outer edge of said target, means for connecting said counter to said cock source upon first receipt of said wave by any said transducers, and for dis-connecting said source from said counter upon the last receipt of a wave by any of said transducers.

8. A target scoring device comprising a compressional acoustic wave-conductive target, a plurality of opposed pairs of transducers positioned symmetrically around the edges of said target and positioned to receive a compressional acoustic wave from a projectile hitting said target, means for detecting signals from said transducers, and measuring the time differential between the arrivals of such an acoustic wave at said transducers, and indicating the time differential between the first detection of a wave by one of said transducers and the detection of said wave by the opposite one of said transducers.

9. A method of detecting the approximate distance of an impact from a pre-determined point in a target area, said method comprising the steps of detecting the first time of arrival of the acoustic wave created by impact at one of a plurality of points arranged in opposed pairs and located equidistant from said pre-determined point, and detecting and indicating the elapsed time between said first arrival at said one point and the arrival of said wave at the opposite point.

10. A method as in Claim 9 including converting said tim difference into a score proportional to the distance of said impact from said point.

11. A system for locating an impact within a target area, said system comprising a plurality of acoustic wave detectors positioned uniformly around said target area, means for indicating which of said detectors first detects an acoustic wave from a target impact, means for indicating which of said detectors is second to detect said acoustic wave, and means for indicating an impact location between said first and second detectors.

12. A system as in claim 11 in which said detectors are located in a circular array and are arranged symmetrically with respect to a point on said target.

13. A device for indicating the approximate azimuth of an impact upon a target, said device comprising a plurality of transducers arranged in a circle, each transducer being located at a point between two adjacent azimuth points, there being one transducer for every other pair of azimuth points, means for detecting the first transducer to receive an acoustic wave from an impact on said target, means for detecting which of the transducers adjacent the first transducer next receives said wave, and means for identifying the azimuth point to the side of said first transducer which is towards the second transducer as the azimuth of the impact.

14. A device as in claim 13 in which said azimuth points correspond to the hour points on a clock face.

15. A device as in claim 14 including indicator devices at a remote location, there being one indicator device for each of said azimuth points.

16. A device as in claim 15 in which said target is a circular metal plate, and said transducers are lead zirconate titanate cells secured to the edge of said plate to receive compressional acoustic waves.

17. A device for scoring and locating an impact on a target, said device comprising means for detecting the maximum time interval between the arrivals of an impact-created acoustic wave at points located adjacent a target uniformly with respect to a point on the target and giving an indication proportional to said maximum time interval, and locating means for indicating to which of said adjacent points said impact is nearest, said detecting and indicating means including a plurality of transducers, one being located at each of said adjacent points, said adjacent points being arranged in a plurality of pairs of opposed transducers, said detecting means detecting the first and last receipts of said wave by said transducers.

18. A device as in claim 17 in which said locating means includes means for detecting which of said transducers is second to receive said wave, and means for for locating said impact as a function of the relative locations of said first and second transducers.

19. A device as in claim 1 including shield means covering said transducers and a portion of said target between said transducers and said point on said target.

20. A device as in claim 19 in which said target is a circular plate, said transducers are secured at the edge of said plate, and said shield has a central circular opening of a diameter substantially less than the diameter of said plate, said opening defining a target area on said plate.

21. A device as in claim 1 in which said target is made of a solid, acoustic wave-conductive material, and including anelastic mounting means for said target.

22. A device as in claim 21 in which said target is metal, and including a mounting plate with said anelastic mounting means fastening said target to said mounting plate adjacent the periphery of said target.

23. A device as in claim 11 in which said target area is on a target member which is made of a solid, acoustic wave-conductive material, and including anelastic mounting means for said target.