Vehicle security system and control method therefor

• US 6,373,381 B2
• Filed: 01/22/2001
• Issued: 04/16/2002
• Est. Priority Date: 01/20/2000
• Status: Expired due to Fees

• Current Assignee: Lite-On Automotive Corp. (Lite-On Technology Corporation)
• Original Assignee: Lite-On Automotive Corp. (Lite-On Technology Corporation)
• Inventors: Wu, Winson
• Primary Examiner(s): Wu, Daniel J.
• Assistant Examiner(s): Nguyen, Phung T
• Application Number:
  US09/765,299
• Publication Number:
  US 20010045890A1
• Time in Patent Office: 449 Days
• Field of Search: 340/426, 340/428, 340/430, 307/10.2, 307/10.5
• US Class Current: 340/426.28
• CPC Class Codes: B60R 25/1001 Alarm systems associated with another car fitting or mechanism, e.g. door lock or knob, pedals features related to the general power supply B60R25/1018
• CPC Class Codes: B60R 25/1004 Alarm systems characterised by the type of sensor, e.g. current sensing means using door lock sensors B60R25/1001

Abstract

Disclosed is a vehicle security system, in which the vehicle security system comprises a control unit having a central processor or microprocessor, a receiver connected to the microprocessor for receiving signals from a remote transmitter. The control unit has an input interface and an output interface. The input interface is connected to various sensors, and the output interface is connected to the vehicle security devices. A PWM interior light delay is disposed between the door sensors and the input interface to provide a voltage pulse signal with width modulation for a vehicle interior lights such that the interior lights are extinguished gradually for a predetermined time. The user can selectively set the vehicle security system whether the vehicle is provided with the PWM interior light delay. When the vehicle security system enters the security armed state, and the vehicle security system is triggered, the vehicle security system will check whether the last closed time of the door trigger switches exceeds a predetermined time (such as 3 second). If the last closed time exceeds the predetermined time, the alarm would be triggered; if the last closed time dose not exceed the predetermined time, the alarm would not be triggered such that the vehicle security system will not be mistriggered.

Claims

1. A vehicle security control method for a vehicle security system to prevent the vehicle security system from being mistriggered, the vehicle security system having at least one door trigger switch to detect the door is open or not;

and a pulse width modulation (PWM) interior light delay connected to the door trigger switch, the pulse width modulation (PWM) interior light delay having a last modulation width time T before the pulse width modulation interior light delay forms the stable state, the control method of the vehicle security system including the following steps of;

starting to arm the security system;

detecting the door trigger switch to check whether the door is in open state, if the door trigger switch is in open state, a door trigger switch by-pass flag is set;

actuating a security detective loop;

if detecting of the door trigger switch is the open state, and the door trigger by-pass flag is set, then go to the step of actuating the security detective loop;

if detecting of the door trigger switch is the open state, the door trigger by-pass flag is not set, and the last close time dose not exceed the predetermined time T, then go to the step of actuating the security detective loop; and

if detecting of the door trigger switch is the open state, the door trigger by-pass flag is not set, and the last close time exceeds the predetermined time T, then trigger the vehicle security system.

2. The control method for a vehicle security system according to claim 1, further comprising the step of disarming the security system.

3. The control method for a vehicle security system according to claim 1, further comprising the step of detecting the ignition switch.

4. The control method for a vehicle security system according to claim 3, wherein if detecting of the door trigger switch is a close state, and the door trigger by-pass flag is not set, then clear the door trigger by-pass flag which has been set.

5. The control method for a vehicle security system according to claim 1, wherein the door trigger switch is a plus trigger switch.

6. The control method for a vehicle security system according to claim 1, wherein the door trigger switch is a minus trigger switch.

7. A vehicle security system including:

a least one door trigger switch to detect whether the door is open or not;

a pulse width modulation (PWM) interior light delay being connected to the at least one door trigger switch, the pulse width modulation (PWM) interior light delay having a last modulation width time T before the pulse width modulation interior light delay forms the stable state;

a device for starting to arm the security system;

a device for detecting the door trigger switch whether be open state or not, if the door trigger switch is open state, a door trigger switch by-pass flag is set;

a device for actuating a security detective loop;

wherein if detecting of the door trigger switch is the open state, and the door trigger by-pass flag is set, then actuating the security detective loop;

if detecting of the door trigger switch is the open state, the door trigger by-pass flag is not set, and the last close time dose not exceed the predetermined time T, then actuating the security detective loop; and

if detecting of the door trigger switch is the open state, the door trigger by-pass flag is not set, and the last close time exceeds the predetermined time T, then triggering the vehicle security system.

8. The vehicle security system according to claim 7, wherein the door trigger switch is a plus trigger switch.

9. The vehicle security system according to claim 7, wherein the door trigger switch is a minus trigger switch.