US5043593A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical theft deterrent system
Assignee: KOKUSAN KINZOKU KOGYO 8-2 2-CHOME KAMATA OTA-KU TOKYO JAPAN A CORP OF JAPAN KK
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Filing: 1989-07-10
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Granted: 1991-08-27
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Expires: 2009-07-10
Abstract
Abstract A new optical theft deterrent device wherein a ray from a light source is divided by a beam splitter mounted on a key into a plurality of light beams which are detected by photosensors to determine authorized use of the key only when predetermined one or ones of the photosensors produce electrical outputs. The beam splitter serves to uniformly divide the ray from the light source into the light beams and also to accurately guide these beams toward the photosensors. The key may be utilized to mechanically and electrically unlock a locking device. The new system may preferably be applied to a steering column shaft locking device to prevent theft of an automotive vehicle on which the system is equipped.
Inventors
- 👤 Shunsaku Tsutsumi
- 👤 Takurou Ozawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:23
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: 5
Claim 1
Independent Claim
195 words
An optical theft deterrent system comprising key means and lock means; said key means including a key blade and a key head, said key blade being provided with notches for mechanical key code, said key head including a beam splitter which comprises an input end for receiving a ray; a transmitting portion having a plurality of optical paths divided from said input end for optical key code; an emitting end formed at each end of said optical paths; said lock means comprising electric lock means and mechanical lock means operable by said key blade of the key means; said electric lock means including a light source for producing the ray; switching means provided in said lock means and being turned on to radiate the ray from the light source toward the input end of the beam splitter when said mechanical lock means is unlocked by the key means; a plurality of photosensors for selectively receiving rays forwarded from said emitting ends of the beam splitter; a comparator for producing a drive signal only when a predetermined combination of said photosensors generates an output; and a driven device operated by the drive signal from said comparator.
Claim 2
Dependent Claim
195 words
An optical theft deterrent system comprising key means and lock means; said key means including a key blade and a key head, said key blade being provided with notches for mechanical key code, said key head including a beam splitter which comprises an input end for receiving a ray; a transmitting portion having a plurality of optical paths divided from said input end for optical key code; an emitting end formed at each end of said optical paths; said lock means comprising electric lock means and mechanical lock means operable by said key blade of the key means; said electric lock means including a light source for producing the ray; switching means provided in said lock means and being turned on to radiate the ray from the light source toward the input end of the beam splitter when said mechanical lock means is unlocked by the key means; a plurality of photosensors for selectively receiving rays forwarded from said emitting ends of the beam splitter; a comparator for producing a drive signal only when a predetermined combination of said photosensors generates an output; and a driven device operated by the drive signal from said comparator.
Claim 3
Dependent Claim
25 words
An optical theft deterrent system as defined in claim 1 wherein said light source includes two infra-red emitting diodes positioned angularly apart from said photosensors.
Claim 4
Dependent Claim
16 words
An optical theft deterrent system as defined in claim 1 wherein said beam splitter is T-shaped.
Claim 5
Dependent Claim
40 words
An optical theft deterrent system as defined in claim 1 wherein at least one of the output ends of the beam splitter is cut off or interrupted to prevent emission of the light beam on corresponding one of said photosensors.
References Cited (Backward Citations)
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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) | 1994-08-26 | 1995-02-25 | 1995-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-26 | 1999-02-25 | 1999-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-26 | 2003-02-25 | 2003-08-27 | $7700.00 | Window Closed / Lapsed |