Security system and method for electronic apparatus, particularly car radios or similar automotive audio equipment

• US 4,720,700 A
• Filed: 01/21/1986
• Issued: 01/19/1988
• Est. Priority Date: 03/16/1985
• Status: Expired due to Fees

• Current Assignee: Blaupunkt-Werke GmbH (Aurelius AG)
• Original Assignee: Blaupunkt-Werke GmbH (Aurelius AG)
• Inventors: Strauss, Karl-Peter, Seibold, Peter
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US06/820,674
• Time in Patent Office: 728 Days
• Field of Search: 340/568, 340/540, 340/63, 340/691, 340/825.31, 340/825.32
• US Class Current: 340/568.1
• CPC Class Codes: B60R 2011/0096 Theft prevention of articles
• CPC Class Codes: G08B 13/1418 Removal detected by failure in electrical connection between the appliance and a control centre, home control panel or a power supply
• CPC Class Codes: H04B 1/082 to be used in vehicles H04B1/086 takes precedence; holding or mounting accessories B60R11/02

Abstract

Upon unauthorized removal of a car radio (2) from the chassis (C) of a car, a memory (5) which has a code stored therein is changed and inhibits operation of the car radio. The memory is retained in a predetermined memory state either by continuously receiving data inputs, for example from a potentiometer slider of a potentiometer (6), or data entered into an RAM energized only upon being properly connected in the vehicle. Alternatively, a user may enter a code, for example by operation of station selector buttons (4) of the car radio (2), and upon operating a set code switch (9), which code is destroyed upon removal of the radio, or upon failure to enter the correct code from time to time. The selected code can be encrypted by a preset encrypting memory chip, for example within the memory (5), and the encrypted code displayed, with only the manufacturer knowing the encrypting data, and releasing the encrypting data only to an authorized person, thereby permitting continued use of the radio by the authorized person even though the code word may have been forgotten.

Claims

1. Security system for electronic appartus, particularly car radios, audio systems, or the like, installed on a support (C) therefore, and energized by an external power source (8) associated with the support, comprising

memory means (5) for storing a predetermined code word;

code entry means (4,9) for entering the code word into the memory means (5);

means coupled to and energized by the external power source or generating an "apparent present" code upon energization thereof by said external power source (8);

means (16,1) for entering the "apparatus present" code in the memory means (5);

removal sensing means (6,7,6'"'"') for electrically sensing removal of the electronic apparatus from the support (C) and deenergization of said "apparatus present" code generating means,

said removal sensing means including a random access memory (RAM (6'"'"') receiving operating voltage from said source (8) which, upon removal of the apparatus from the support, is interrupted;

and logic means (1) connected to the memory means (5), the code entering means (4), and the removal sensing means (6,7,6'"'"') said logic means inhibiting operation of the electronic apparatus (2) after removal from the support and failure to sense the "apparatus present" code, until the code word is again entered into said code entering means and stored in the memory means.

2. System according to claim 1, wherein the electronic apparatus comprises an automobile radio, and the support comprises a portion (C) of the chassis of the automobile, said automobile radio having an alphanumerical display (3) and control elements (4) coupled to the radio which, upon operation thereof, causes the display (3) to indicate a function selected by a control element;

and wherein the code entering means (1, 4;

6, 6'"'"') for entering the code words into the memory comprises said control buttons, the function of which is displayed by said display.

3. System according to claim 2, wherein the control elements are station selector control elements of the car radio.

4. System according to claim 2, wherein the display, upon operation of a control element, displays, sequentially, a set of alphanumerical indicia;

said logic means sensing operation of a selected control element and, upon change in state of the control element when a specific alphanumerical indicium is displayed, entering a representative datum in the memory, said datum forming part of the code word.

5. System according to claim 1, wherein a display (3) is provided;

and said memory (5) includes a storage field for encrypting a selected code word and, after entry of an incorrect code word, the display (3) displays the encrypted code word.

6. System according to claim 1, wherein the logic means includes a timing arrangement which inhibits operation of the apparatus for a predetermined time period after entry of an incorrect code word.

7. System according to claim 6, wherein, upon sequential entry of incorrect code words, the inhibiting time for the apparatus increases.

8. Security system for electronic apparatus, particularly car radios, audio systems, or the like, installed on a support (C) therefor, and energized by an external power source (8) associated with the support, comprising

memory means (5) for storing a predetermined code word;

code entry means (4,9) for entering the code word into the memory means (5);

means coupled to and energized by the external power source for generating an "apparatus present" code upon energization thereof by said external power source (8);

means (16,1) for entering the "apparatus present" code in the memory means (5);

removal sensing means (6,7,6'"'"') for electrically sensing removal of the electronic apparatus from the support (C) and deenergization of said "apparatus present" code generating means,

said removal sensing means including a potentiometer (6) coupled to the support (C) and providing the "apparatus present" signal representative of a set position of the potentiometer when the apparatus is located in the support, said potentiometer changing setting upon removal of the electronic apparatus from the support;

means (7,1,5) comparing the potentiometer setting upon reenergization of the electronic apparatus with a set position previously stored in the memory means (5);

and logic means (1) connected to the memory means (5), the code entering means (4), and the removal sensing means (6,7,6'"'"') said logic means inhibiting operation of the electronic apparatus (2) after removal from the support and failure to sense the "apparatus present" code, until the code word is again entered into said code entering means and stored in the memory means.

9. System according to claim 8, wherein the electronic apparatus comprises an automobile radio, and the support comprises a portion (C) of the chassis of the automobile, said automobile radio having an alphanumerical display (3) and control elements (4) coupled to the radio which, upon operation thereof, causes the display (3) to indicate a function selected by a control element.

10. System according to claim 9, wherein the display, upon operation of a control element, displays, sequentially, a set of alphanumerical indicia;

said logic means sensing operation of a selected control element and, upon change in state of the control element when a specific alphanumerical indicium is displayed, entering a representative datum in the memory, said datum forming part of the code word.

11. System according to claim 8, wherein a display (3) is provided;

and said memory (5) includes a storage field for encrypting a selected code word and, after entry of an incorrect code word, the display (3) displays the encrypted code word.

12. System according to claim 8, wherein the logic means includes a timing arrangement which inhibits operation of the apparatus for a predetermined time period after entry of an incorrect code word.

13. System according to claim 12, wherein, upon sequential entry of incorrect code words, the inhibiting time for the apparatus increases.

14. Security system for electronic apparatus, particularly car radios, audio systems, or the like, installed on a support (C) therefor, and energized by an external power source (8) associated with the support, comprising

memory means (5) for storing a predetermined code word;

the memory means (5);

means coupled to and energized by the external power source for generating an "apparatus present" code upon energization thereof by said external power source (8);

means (16,1) for entering the "apparatus present" code in the memory means (5);

removal sensing means (6,7,6'"'"') for electrically sensing removal of the electronic apparatus from the support (C) and deenergization of said "apparatus present" code generating means,

and logic means (1) connected to the memory means (5), the code entering means (4), and the removal sensing means (6,7,6'"'"') said logic means inhibiting operation of the electronic apparatus (2) after removal from the support and failure to sense the "apparatus present" code, until the code word is again entered into said code entering means and stored in the memory means,

wherein the logic means includes a timing arrangement which inhibits operation of the apparatus for a predetermined time period after entry of an incorrect code word.

15. System according to claim 14, wherein, upon sequential entry of incorrect code words, the inhibting time for the apparatus increases.

16. Security system for electronic apparatus consisting of car audio equipment, particularly car radios, radio--cassette recorder combinations, citizen band radios, and the like,

said electronic apparatus being intalled in an automotive vehicle having a battery forming a power source, said vehicle further providing a support (C) for said apparatus,

said security system comprising

memory means (5) for storing a predetermined code word;

code entry means (4,9) for entering the code word into the memory means (5);

means coupled to and energized by the external power source for generating an "apparatus present" code upon energization thereof by said external power source (8);

means (16,1) for entering the "apparatus present" code in the memory means (5);

removal sensing means (6,7,6'"'"') for electrically sensing removal of the electronic apparatus from the support (C) and deenergization of said "apparatus present" code generating means;

and logic means (1) connected to the memory means (5), the code entering means (4), and the removal sensing means (6,7,6'"'"'), said logic means inhibiting operation of the electronic apparatus (2) after removal from the support and failure to sense the "apparatus present" code, until the code word is again entered into said code entering means and stored in the memory means;

wherein the logic means includes a timing arrangement which inhibits operation of the apparatus for a predetermined time period after entry of an incorrect code word.

17. System according to claim 16, wherein, upon sequential entry of incorrect code words, the inhibiting time for the apparatus increases.

18. Security system for electronic apparatus consisting of car audio equipment, particularly car radios, radio--cassette recorder combinations, citizen band radios, and the like, said electronic apparatus being installed in an automotive vehicle having a battery forming a power source, said vehicle further providing a support (C) for said apparatus,

said security system comprising

memory means (5) for storing a predetermined code word;

code entry means (4,9) for entering the code word into the memory means (5);

means coupled to and energized by the external power source for generating an "apparatus present" code upon energization thereof by said external power source (8);

means (16,1) for entering the "apparatus present" code in the memory means (5);

said removal sensing means including a random access memory (RAM) (6'"'"') receiving operating voltage from said source (8) which, upon removal of the apparatus from the support, is interrupted.

and logic means (1) connected to the memory means (5), the code entering means (4), and the removal sensing means (6,7,6'"'"'), said logic inhibting operation of the electronic apparatus (2) after removal from the support and failure to sense the "apparatus present" code, until the code word is again entered into said code entering means and stored in the memory means.

19. System according to claim 18, wherein the car radio comprises an alphanumerical display (3) and control elements or buttons (4) to control the radio, said display displaying, in alphanumerical form, a representation of the selected function;

and wherein the code entering means (4) comprises the control elements or buttons (4).

20. System according to claim 19, wherein the control elements are station selector control elements of the car radio.

21. System according to claim 20, wherein said memory (5) includes a storage field for encrypting a selected code word and, after entry of an incorrect code word, the display (3) displays the encrypted code word.

22. System according to claim 19, wherein the display, upon operation of a control element, displays, sequentially, a set of alphanumerical indicia;

said logic means sensing operation of a selected control element and, upon change in state of the control element when a specific alphanumerical indicium is displayed, entering a representative datum in the memory, said datum forming part of the code word.

23. System according to claim 18, wherein the logic means includes a timing arrangement which inhibits operation of the apparatus for a predetermined time period after entry of an incorrect code word.