EP0351183A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical theft deterrent system
Assignee: Alpha Corp
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Filing: 1989-07-11
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Granted: —
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Expires: 2009-07-11
Abstract
Abstract A new optical theft deterrent device is disclosed wherein a ray from a light source (22) is divided by a beam splitter (13) mounted on a key (10) into a plurality of light beams which are detected by photosensors (14-17) to determine authorized use of the key (10) only when predetermined one or ones of the photosensors (14-17) produce electrical outputs. The beam splitter (13) serves to uniformly divide the ray from the light source (22) into the light beams and also to accurately guide these beams toward the photosensors (14-17). The key (10) may be utilized to mechanically and electrically unlock a locking device (19, 20). The new system may preferably be applied to a steering column shaft locking device (19) to prevent theft of an automotive vehicle on which the system is equipped.
Inventors
- 👤 Shunsaku Tsutsumi
- 👤 Takurou Ozawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 11:21
CPC Classifications
B; B60; B60R; B60R25/00; B60R25/01; B60R25/02; B60R25/021; B60R25/04; B60R25/20; B60R25/2063; B60R25/24; E; E05; E05B; E05B49/00; E05B49/002; E05B49/006; G; G07; G07C; G07C9/00; G07C9/00174; G07C9/00944; G07C2009/00753; G07C2009/00769; G07C2009/00785; Y; Y10; Y10T; Y10T70/00; Y10T70/70; Y10T70/7051; Y10T70/7062; Y10T70/7068; Y10T70/7073; Y10T70/7079
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
53 words
(1) An optical theft deterrent system comprising the steps of emitting a ray from a light source, dividing said ray into a plurality of light beams by a beam splitter, detecting the divided light beams by corresponding photosensors, and producing an unlocking signal when predetermined one or ones of said photosensors generates outputs.
Claim 2
Dependent Claim
49 words
(2) An optical theft deterrent system as defined in claim 1 wherein said ray is divided into at least four light beams by said beam splitter, and at least one of said light beams is prevented from being emitted on one of said photosensors to provide a key code.
Claim 3
Dependent Claim
26 words
(3) An optical theft deterrent system as defined in claim 1 wherein said light beams are angularly turned by approximately 180 degrees within said beam splitter.
Claim 4
Dependent Claim
18 words
(4) An optical theft deterrent system as defined in claim 1 wherein said ray is infra-red or visible.
Claim 5
Dependent Claim
76 words
(5) An optical theft deterrent device comprising: a light source for producing a ray; a beam splitter for receiving and dividing said ray into a plurality of light beams; a plurality of photosensors for generating outputs upon receiving said divided light beams emitted from said beam splitter; a comparator for producing an output only when predetermined ones of said photosensors receives the divided light beams, and a driven device operated by the output from said comparator.
Claim 6
Dependent Claim
68 words
(6) An optical theft deterrent device as defined in claim 5 wherein said beam splitter is made of a light permeable material such as acryl resin, polycarbonate or glass, said beam splitter comprising a input end for receiving said ray from said light source, a transmitting portion having four optical paths divided from said input end, and an output end formed at each end of said optical paths.
Claim 7
Dependent Claim
22 words
(7) An optical theft deterrent device as defined in claim 5 wherein said beam splitter is encapsulated by an opaque resin material.
Claim 8
Dependent Claim
29 words
(8) An optical theft deterrent device as defined in claim 5 wherein said transmitting portion of said beam splitter is mounted within a key head formed of a resin.
Claim 9
Dependent Claim
30 words
(9) An optical theft deterrent device as defined in claim 5 wherein said output end of said beam splitter is concealed by a cover made of infra-red light permeable material.
Claim 10
Dependent Claim
37 words
(10) An optical theft deterrent device as defined in claim 6 wherein at least one of said output ends is cut off or interrupted to prevent emittion of the light beam on corresponding one of said photosensors.
Claim 11
Dependent Claim
143 words
(11) An optical theft deterrent device comprising: alight source for emitting a ray; a beam splitter for dividing said ray into a plurality of light beams; a plurality of photosensors for generating outputs upon receiving said divided light beams; code storage means for storing signals which are representative of a specific key code; a comparator for comparing the coded signals stored in said code storge means with outputs of said photosensors and for producing an output when the outputs of said photosensors match the signals from said code storage means; a driven device operated by the output from said comparator; and switching means for changing said code storage means to a reading mode wherein said code storage means supplies the coded signals to said comparator or to a writing mode wherein said code storage means stores new coded signals received by said photosensors.
Claim 12
Dependent Claim
136 words
(12) An optical theft deterrent device comprising: a light source for producing a ray; a beam splitter for dividing said ray into a plurality of light beams; a plurality of photosensors for generating outputs upon receiving said divided light beams; code storage means for storing signals which are representative of a specific key code; a comparator for comparing coded signals stored in said code storge means with outputs of said photosensors and for producing an output when the outputs of said photosensors match the signals from said code storage means; a driven device operated by the output from said comparator; and a steering column shaft locking device for supporting said light source and photosensors around a key hole of said locking device, said photosensors being arranged in a row angularly spaced relation to said light source.
Claim 13
Dependent Claim
30 words
(13) An optical theft deterrent device as defined in claim 12 further comprising a cap made of an infra-red ray permeable but visible ray impermeable resin for concealing said photosensors.
Claim 14
Dependent Claim
106 words
(14) An optical theft deterrent device comprising: a light source for generating a ray; a beam splitter for dividing said ray into a plurality of light beams; a plurality of photosensors for generating outputs upon receiving said divided light beams; code storage means for storing signals which are representative of a specific key code; a comparator for comparing coded signals stored in said code storge means with outputs of said photosensors and for producing an output when the outputs of said photosensors match the signals from said code storage means; and a starter relay for driving a starter moter upon receiving the output from said comparator.
Claim 15
Dependent Claim
94 words
(15) A beam splitter comprising: an input end for receiving a ray from a light source; a transmitting portion having a plurality of optical paths divided from said input end; an emitting end formed at each end of said opticalpaths; a first reflective surface for reflecting said light beam passing through said transmitting portion substantially at a right angle; branched portions for dividing said ray into a plurality of light beams along said optical paths; and a second reflective surface for directing each of light beams divided to corresponding one of said output ends.
Claim 16
Dependent Claim
33 words
(16) A beam splitter as defined in claim 15 wherein said first reflective surface is a paraboloid whose focus is placed in said light source in a spaced relation to said input end.
Claim 17
Dependent Claim
34 words
(17) A beam splitter as defined in claim 15 further comprising a third inclined reflective surface provided at said input end for reflecting said ray from said light source toward said first reflective surface.
Claim 18
Dependent Claim
24 words
(18) A beam splitter as defined in any one of claims 15 to 16 wherein the total surface of said beam splitter is mirror-finished.
Claim 19
Dependent Claim
29 words
(19) A beam splitter as defined in claim 15 wherein said second reflective surfaces reflect substantially at a right angle said light beam reflected on said first reflective surface.
Claim 20
Dependent Claim
30 words
(20) A beam splitter as defined in claim 15 wherein said first reflective surface is inclined at an angle slightly smaller than a critical angle on said first reflective surface.
References Cited (Backward Citations)
No citation records indexed.
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