ANTI-THEFT ALARM SYSTEM FOR PORTABLE COMPUTER

Abstract

An anti-theft alarm system includes a switch-detecting portion including a first switch and a second switch, a controller, a button for enabling the alarm system. If the portable computer is moved without deactivation of the alarm system, the second switch opens, causing a change of a voltage at the first switch which is detected by the controller, the controller thereby sends an alarm control signal to an audio system of the portable computer, and the audio system produces an audible sound for a theft deterrence effect.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an anti-theft alarm system for a portable computer, in accordance with a preferred embodiment of the present invention;

FIG. 2 is a schematic diagram of an audio system of FIG. 1, in accordance with a preferred embodiment of the present invention;

FIG. 3 is a schematic diagram of a switch-detecting portion of FIG. 1, in accordance with a preferred embodiment of the present invention; and

FIG. 4 is a schematic diagram of two switches mounted in the portable computer of FIG. 1, in accordance with a preferred embodiment of the present invention.

Claims

1. An anti-theft alarm system for a portable computer, the anti-theft alarm system comprising: a switch-detecting portion comprising a first switch and a second switch;a controller configured for outputting an enable signal to the first switch to activate the alarm system and protect the portable computer from theft;a button configured for delivering an alarm system enabling signal to the controller and causing the controller to output the enable signal, whereinif the portable computer is moved without deactivation of the alarm system, the second switch opens, causing a change of a voltage at the first switch which is detected by the controller, the controller thereby sends an alarm control signal to an audio system of the portable computer, and the audio system produces an audible sound for a theft deterrence effect.

2. The anti-theft alarm system as claimed in claim 1, wherein the first switch is an electronic switch, the second switch is a mechanical switch, the second switch is mounted in a cushion of the portable computer and deformable via an outside force.

3. The anti-theft alarm system as claimed in claim 2, wherein the switch-detecting portion further comprises a diode connected between the electronic switch and the controller for avoiding leakage.

4. The anti-theft alarm system as claimed in claim 1, wherein the audio system comprises: a speaker;a codec for converting the alarm control signal to an analog audio signal; andan audio amplifier for amplifying the analog audio signals to make the speaker sound an alarm.

5. The anti-theft alarm system as claimed in claim 4, wherein the audio system further comprising a transistor, the transistor having a collector connected to an earphone input of the audio amplifier, and a base receiving an earphone bypass input signal from the controller for making the speaker sound the alarm even if an earphone is plugged into the portable computer.

6. The anti-theft alarm system as claimed in claim 4, wherein the controller outputs a mute-disabling signal to the audio amplifier for disabling a possible mute status of the audio system.

7. The anti-theft alarm system as claimed in claim 1, further comprising a central processing unit connected to the audio system via a memory controller hub and an input/output controller hub for calling an audio driver when the controller outputs the alarm control signal.

8. The anti-theft alarm system as claimed in claim 1, further comprising a memory connected to the controller for storing a password to be input to the portable computer for enabling and/or disabling the alarm system.

9. The anti-theft alarm system as claimed in claim 1, further comprising an indicator connected to the controller for indicating whether the alarm system is enabled or not.

10. An anti-theft alarm system for a portable computer, the anti-theft alarm system comprising: a switch-detecting portion comprising a first switch and a second switch, the second switch being deformable under pressure exerted by a weight of the portable computer;a controller for outputting an enable signal to the first switch to activate the alarm system and protect the portable computer from theft;a button for delivering an alarm system enabling signal to the controller and causing the controller to output the enable signal; andan audio system connected to the controller, wherein if the portable computer is moved without deactivation of the alarm system, the second switch opens, causing a change of a voltage at the first switch, which is detected by the controller, the controller thereby sends an alarm control signal to an audio system of the portable computer, and the audio system produces an audible sound for a theft deterrence effect.

11. The anti-theft alarm system as claimed in claim 10, wherein the first switch is an electronic switch, the second switch is a mechanical switch, and the second switch is mounted in a cushion of the portable computer.

12. The anti-theft alarm system as claimed in claim 11, wherein the switch-detecting portion further comprises a diode connected between the electronic switch and the controller for avoiding leakage.

13. The anti-theft alarm system as claimed in claim 10, wherein the audio system comprises: a speaker;a codec for converting the alarm control signal to an analog audio signal; andan audio amplifier for amplifying the analog audio signals to make the speaker sound an alarm.

14. The anti-theft alarm system as claimed in claim 13, wherein the audio system further comprising a transistor, the transistor having a collector connected to an earphone input of the audio amplifier, and a base receiving an earphone bypass input from the controller for making the speaker sound the alarm even if an earphone is plugged into the portable computer.

15. The anti-theft alarm system as claimed in claim 13, wherein the controller outputs a mute-disabling signal to the audio amplifier for disabling a possible mute status of the audio system.

16. The anti-theft alarm system as claimed in claim 10, further comprising a central processing unit connected to the audio system via a memory controller hub and an input/output controller hub for calling an audio driver when the controller outputs the alarm control signal.

17. The anti-theft alarm system as claimed in claim 10, further comprising a memory connected to the controller for storing a password to be input to the portable computer for enabling and/or disabling the alarm system.

18. The anti-theft alarm system as claimed in claim 10, further comprising an indicator connected to the controller for indicating whether the alarm system is enabled or not.