Anti-theft system for a vehicle

• US 4,965,460 A
• Filed: 08/24/1988
• Issued: 10/23/1990
• Est. Priority Date: 08/25/1987
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company), Kabushiki Kaisha Honda Lock
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company), Kabushiki Kaisha Honda Lock
• Inventors: Tanaka, Akira, Sakata, Kazuhiro, Fukamachi, Masaaki
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): Logan, Sharon D.
• Application Number:
  US07/236,063
• Time in Patent Office: 790 Days
• Field of Search: 307/10 AT, 307/10.2, 307/10.3, 307/10.4, 340/64, 340/542, 340/543, 340/573, 340/576, 180/287
• US Class Current: 307/10.2
• CPC Class Codes: B60R 25/04 operating on the propulsion system, e.g. engine or drive motor
• CPC Class Codes: B60R 25/2063 Ignition switch geometry
• CPC Class Codes: B60R 25/23 using manual input of alphanumerical codes
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user
• CPC Class Codes: G07C 2009/00785 by light
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks

Abstract

A vehicular anti-theft system, comprising: a mechanical key switch which can be turned with a matching mechanical key between a first angular position suitable for receiving the mechanical key therein and corresponding to an inoperative state of the vehicle and a second angular position corresponding to an operative state of the vehicle; electronic code matching circuit for detecting an electronic code signal transmitted from a transmitter incorporated in a part of the mechanical key; a control circuit which enables the vehicle when the mechanical key switch is turned with a matching key to the second angular position and the electronic code matching circuit has detected the matching code signal from the transmitter; a trigger circuit which acts upon the control circuit into detecting the matching code signal transmitted from the transmitter; wherein the trigger circuit is activated when the angular position of the mechanical key switch is set to a certain position preceding the position for starting the vehicle. Thereby, the process of code matching is performed before the ignition key switch is turned to the position for starting the vehicle, and the time required to start the vehicle is not increased by this code matching process.

Claims

1. A vehicular anti-theft system for a vehicle, comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle, and a second position corresponding to an operative state of said vehicle;

electronic code matching means for detecting an electronic code signal transmitted from a transmitter incorporated in said key;

control means for enabling said vehicle when said key switch is turned with said matching key to said second position and said electronic code matching means has detected a matching code signal from said transmitter; and

trigger means for acting upon said control means so as to detect said matching code signal transmitted from said transmitter;

wherein said trigger means is activated when the position of said key switch is between a third position, which is between said first position and said second position, and a fourth position, which is between said third position and said second position.

2. A vehicular anti-theft system as defined in claim 1, wherein said key switch and said key are provided with contact means which establish an electric contact therebetween when said key is inserted into said key switch at said first position, said trigger means being activated when said electric contact is established.

3. A vehicular anti-theft system as defined in claim 1, wherein said key switch and said key comprise contact means for establishing an electric contact therebetween when said key switch is located between said third and fourth positions, said trigger means being activated when said electric contact is established.

4. A vehicular anti-theft system as defined in claim 1, wherein said control means is provided with memory means which permits said vehicle to be enabled when said key switch is turned with said matching key to said second position without involving the process of detecting said matching code signal by said code matching means, for a certain time interval after said code matching means has detected said matching electronic code.

5. A vehicular anti-theft system as defined in claim 1, wherein said control means is provided with memory means which permits said vehicle to be enabled when said key switch is turned with said matching key to said second angular position without involving the process of detecting said matching code signal by said code matching means, as long as said key is no longer kept inserted in said key switch after said code matching means has detected said matching electronic code.

6. A vehicular anti-theft system as defined in claim 1, wherein said control means is provided with memory means which permits said vehicle to be enabled when said key switch is turned with said matching key to said second angular position without involving the process of detecting said matching code signal by said code matching means, as long as said key switch is no longer kept within a certain range of its position after said code matching means has detected said matching electronic code.

7. A vehicular anti-theft system as defined in claim 1, wherein said control means comprises a self retaining circuit which maintains said enabled state of said vehicle once said vehicle is enabled.

8. A vehicular anti-theft system comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle, and a second position corresponding to an operative state of said vehicle;

electronic code matching means for detecting an electronic code signal transmitted for a transmitter incorporated in said key;

control means for enabling said vehicle when said key switch is turned with said key to said second position and said electronic code matching means has detected a matching code signal from said transmitter; and

trigger means for acting upon said control means so as to detect said matching code signal transmitted from said transmitter;

wherein said trigger means is activated when the position of said key switch is between a third position, which is between said first position and said second position, and a fourth position, which is between said third position and said second position;

wherein said key switch and said key comprises means for signal transmitting and means for signal receiving respectively, said trigger means being activated when said signal receiving means receives a certain signal from said signal transmitting means.

9. A vehicular anti-theft system comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle, and a second position corresponding to an operative state of said vehicle;

electronic code matching means for detecting an electronic code signal transmitted from a transmitter incorporated in said key;

control means for enabling said vehicle when said key switch is turned with said key to said second position and said electronic code matching means has detected a matching code signal from said transmitter; and

trigger means for acting upon said control means so as to detect said matching code signal transmitted from said transmitter;

wherein said trigger means is activated when the position of said key switch is between a third position, which is between said first position and said second position, and a fourth position, which is between said third position and said second position;

wherein said transmitter comprises a switch an operation of which causes said transmitter to activate onboard equipment, said transmitter producing two distinct code signals depending on whether said transmitter is activated by said trigger means or by said switch.

10. A vehicular anti-theft system as defined in claim 9, wherein said on-board equipment comprises a vehicle door lock, and the code signal for activating said vehicle door lock is of a different time duration than the code signal for enabling said vehicle.

11. A vehicular anti-theft system comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle, and a second position corresponding to an operative state of said vehicle;

electronic code matching means for detecting an electronic code signal transmitted from a transmitter incorporated in said key;

control means for enabling said vehicle when said key switch is turned with said key to said second position and said electronic code matching means has detected a matching code signal from said transmitter; and

trigger means for acting upon said control means so as to detect said matching code signal transmitted from said transmitter;

wherein said trigger means is activated when the position of said key switch is between a third position, which is between said first position and said second position, and a fourth position, which is between said third position and said second position;

further comprising keyboard means for entering a code therefrom into said control means, the entering of said code acting upon said control means to enable said vehicle by turning said key switch with said key to said second position.

12. A vehicular anti-theft system as defined in claim 11, wherein the vehicle is enabled by entering of said code from said keyboard mans when said key switch is turned with said key to said second position at a certain time relative to the time at which said code is entered from said keyboard means.

13. A vehicular anti-theft system comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle, and a second position corresponding to an operative state of said vehicle;

electronic code matching means for detecting an electronic code signal transmitted from a transmitter incorporated in said key;

control means for enabling said vehicle when said key switch is turned with said key to said second position and said electronic code matching means has detected a matching code signal from said transmitter; and

trigger means for acting upon said control means so as to detect said matching code signal transmitted from said transmitter;

wherein said trigger means is activated when the position of said key switch is between a third position, which is between said first position and said second position, and a fourth position, which is between said third position and said second position;

wherein said key comprises a rechargeable battery for supplying electric power to said transmitter, a switch for activating said transmitter, and first contact means for connecting to said rechargeable battery; and

said key switch comprises second contact means for establishing an electric contact with said first contact means of said key when said key is inserted into said key switch, said control means disabling the activation of said transmitter by means of said switch when said rechargeable battery receives electric power via said first contact means.

14. A vehicular anti-theft system for a vehicle comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle and a second position corresponding to an operative state of said vehicle;

electronic code matching means for receiving an electronic code signal from a transmitter incorporated in said key only at a time during and after turning of said key; and

control means for enabling said vehicle when said key switch is turned with said key to said second position and for disabling said vehicle when said electronic code matching means has failed to receive a matching code signal from said transmitter after said vehicle has been enabled.

15. A vehicular anti-theft system for a vehicle comprising:

a key switch turnable with a matching key between a first position suitable for receiving said key therein and corresponding to an inoperative state of the vehicle and a second position corresponding to an operative state of said vehicle;

electronic code matching means for detecting an electronic code signal transmitted from a transmitter which is incorporated in a part of said key; and

control means for enabling said vehicle when said key switch is turned with said matching key to said second position and for issuing a warning when said electronic code matching means has failed to receive a matching code signal from said transmitter.