JPH0546535Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a vehicle theft alarm device that detects when a thief opens a door or the like by illegal means and issues an alarm.

(Prior Art) Conventionally, anti-theft devices for automobiles have been designed to prevent theft from third parties by keeping a locking device provided on the door in a locked state. However, due to its structure, the locking mechanism of such a locking device is often relatively easily unlocked by inserting a thin bar-shaped plate between the door and the window glass and pulling the link on the inside of the door. If such a situation occurs and a thief intrudes into the vehicle interior, it is desirable to provide some kind of warning to prevent the vehicle from being stolen. Therefore,
Recently, alarm devices have been developed that issue an alarm, such as by sounding a horn, if a door or the like is forcibly opened while the car is parked.

However, this alarm system normally starts detecting the intrusion of a thief when the door is fully closed and the door lock mechanism of all doors is locked.
For example, there is a drawback that the vehicle automatically enters a theft alert state regardless of the driver's intention after getting out of the vehicle.

Therefore, at present, the theft alarm operation is not started simply when a fully closed door or all door locks are detected, but the theft alarm operation is started only when a specific door closing operation such as a keyless lock is performed, for example. A theft alarm system is being considered. In other words, for example, when the front door is detected to be opened and a door lock operation is detected, this theft alarm device determines that the vehicle is parked due to the keyless lock and detects the intrusion of a thief. It is a start. However, if the keyless lock fails to close the door, the door may remain locked for a moment and be left ajar again. It is hoped that the transition will not occur.

(Problems to be solved by this invention) This invention starts a theft alarm operation by keyless lock operation according to the driver's intention.If the keyless lock fails, the door closes →
It is an object of the present invention to provide a vehicle theft alarm device in which a theft alarm process is not executed when an opening is detected.

[Structure of the idea]

(Means and effects for solving the problem) In other words, the vehicle theft alarm system according to this invention further confirms that all doors are closed after a certain period of time has elapsed after the door lock operation when the door is opened, and detects an intruder. Detection is started after the door is closed, and even if the door is detected to be closed and then opened, if the door is detected to be locked, the system does not proceed to the theft alarm process.

(Example) The following drawings 1 to 3 show the first example of this invention.
An example will be explained.

Figure 1 shows its circuit configuration. In the figure, reference numeral 10 denotes an ultrasonic sensor that is integrally installed in the room lamp unit on the ceiling of the vehicle interior, as shown in Figure 2. The ultrasonic waves are received by the receiver 10b. Further, the controller 11 controls the transmission of ultrasonic waves from the transmitter 10a and detects the ultrasonic frequency received by the receiver 10b.

The controller 11 controls the apparatus and is composed of, for example, a microcomputer. Further, PSW is a power switch, and when it is closed, power B is supplied to the controller 11. IGSW is a switch for the ignition key hole and is closed when the ignition key is not inserted into the ignition key hole. DKSW1
is the switch for the front right door key hole, DKSW
Reference numeral 2 designates a switch for the front left door key hole which is connected in series to the switch DKSW1 and is closed when no ignition key is inserted into each door key hole. DLSW1 is a switch for front right door lock, DLSW2 is a switch for front left door lock, DLSW3 is a switch for rear right door lock, and DLSW4 is a switch for rear left door lock. Each switch is closed when the door is unlocked. be done. TRSW
is a trunk switch that closes when the trunk hood is opened. DSW1 to DSW4 are switches for the four front and rear doors, and are closed when each door is opened.

Further, 12 is a horn that emits an alarm sound, one end of which is connected to the power source B, and the other end of which is connected to the controller 11 via line a. Here, the other end of the horn 12 is also connected to a horn switch HSW provided on the handle. 13 is a headlight whose lighting is controlled by a relay 14; 15 is a taillight whose lighting is controlled by a relay 16; and 17 is an ignition coil whose operation is controlled by a relay 18. Here, the relay coil 14 of the relay 14
One end of 1 is connected to the power supply B, and the other end is connected to the controller 11 via line b.
Further, one end of the relay switch 14S is connected to the power source B, and the other end is connected to the headlight 13. Here, the relay coil 14l
The other end is connected to a light switch LSW1 located near the handle. Further, one end of the relay coil 16l of the relay 16 is connected to the power source B, and the other end is connected to the controller 11 via line c. Further, one end of the relay switch 16S is connected to the power source B, and the other end is connected to the tail light 15. Further, the relay coil 16l is connected to a taillight lighting switch LSW2 disposed near the steering wheel. Furthermore, one end of the relay 18l is connected to the power source B, and the other end is connected to the controller 11 via line d. Relay switch 1
8S is opened when the relay coil 18l is excited, and thereby the ignition coil 1
One terminal of 7 is grounded. Note that when the relay switch 18S is not closed, one terminal of the ignition coil 17 is connected to the distributor. This provides an ignition pulse to the spark plug, allowing the engine to start. Reference numeral 19 is an indicator lamp whose one end is connected to the power source B and the other end is connected to the controller 11. This indicator lamp 19 is activated when a predetermined door lock operation is performed at the driver's will. When the conditions for starting the detection of intrusion by a thief are met, the lighting is controlled for a certain period of time (standby period) until the actual detection operation starts.

Next, the operation of the theft alarm device configured as described above will be explained. First, turn on the power switch.
When the PSW is turned on, the controller 11 performs the processing shown in the flowchart of FIG.

First, the flag that is set when the ultrasonic sensor 10 starts operating is reset (step
S1). Then, a timer to be described later is reset (step S2). Next, it is determined whether the above flag is set (step S3). Here, since the flag has been reset in step S1, the conditions for operating the ultrasonic sensor 10 in steps S4 to S7 are determined.
In other words, if the driver wants to activate the theft alarm while away from his/her vehicle, he/she must turn on the power switch.
Although the PSW is turned on, whether or not the device is actually activated depends on the condition determination process in steps S4 to S7 and the subsequent standby process for starting theft detection detection in steps S7a to S10b.

In this embodiment, when the ignition key is turned off and removed from the key hole, the trunk is closed, and the front door is confirmed to be locked with the front door open, the standby mode starts operations in steps S7a to S10b. After the process and the process of step S11, the ultrasonic sensor 10 starts the operation of detecting a thief's intrusion in step S12. In such a case, first select ``NO'' in step S4, ``YES'' in step S5, and ``YES'' in step S5.
It is determined as ``YES'' in S6 and ``YES'' in step S7, and the process proceeds to step S7a. In other words, if you operate the door lock with the front door open, it can be determined that you are locking the door and parking the vehicle without using the ignition key. If it is confirmed that the front door is not in use, especially that the front door is locked, the process proceeds to the standby process starting from step S7a.

That is, based on the vehicle parking confirmation judgment in steps S4 to S7 above, when it is confirmed that the conditions for starting the detection of theft by the thief have been met and that the driver has the intention of actually activating the present theft alarm system, the step
In S7a, the indicator lamp 19 is turned on to enter an intrusion detection standby state. Note that the judgment operations in steps S4 to S7 above are performed using a switch.
IGSW, TRSW, DLSW1, DLSW2, DLSW
3, DLSW4, is performed based on signals from DSW1 to DSW4.

If the timer reset in step S2 is not activated (step
If “NO” in S8), the timer starts clocking in the controller 11 (step
S9). Thereafter, the determination as to whether or not the standby state release signal has been received in step S9a is repeated until 20 seconds have been counted by the timer (step S10). Here, the above-mentioned standby state release signal means that the door is unlocked using the official ignition key, or the correct ignition key is inserted into the ignition key hole, etc. This signal is a signal for canceling the condition for starting intrusion detection by normal operation, and when this cancellation signal is received ("YES" in step S9a), the process returns to step S2.

On the other hand, when the 20 second time period ends in step S10, it is confirmed in step S10a that all doors are closed, and then the process proceeds to step S10b.
Indicator lamp 19 by controller 11
is turned off, a flag is set (step S11), and detection of the thief's intrusion by the ultrasonic sensor 10 is started (step S12). In other words,
When the driver's intention to actually start the theft warning operation is confirmed by the determination operations in steps S4 to S7, the transmitter 10a and the receiver 1 go through the standby state including confirmation of the rear door lock.
At 0b, transmission and reception of ultrasonic waves is started, and a detection and warning operation against intrusion of a thief into the vehicle interior is started. Thereafter, the process returns to step S2 and the timer is reset, but since the flag has been set, the process proceeds to step S13 and subsequent steps via step S3. In this case, simply close all the doors of the vehicle and
Rather than a conditional judgment that locks all doors,
The system does not shift to the actual warning operation unless the driver performs a specific keyless lock operation, which indicates the intention to park the vehicle, by locking the front door when the front door is open, so that the driver's intention after getting out of the car is not affected. The theft alarm device can be activated or deactivated according to the user's preference. It should be noted that whether or not the intruder detection operation is actually started after the front door opening/locking operation is performed can be determined by checking the lighting of the indicator lamp 19.

Next, the process from step S13 onwards is a process of detecting the thief's intrusion into the vehicle interior and issuing a warning.

First, if no object (including the ignition key or other sticks used to pry open the door) is inserted into the key hole of the door, the door or trunk is closed, and the ultrasonic sensor 10 is not receiving the signal. Machine 10b
If there is no change in the ultrasonic waves received and detected, for example, there is no change in frequency due to the Doppler effect, no alarm processing as described below will be performed. That is, the determination in step S13 is "NO", the determination in step S14 is "YES", the determination in step S15 is "YES", and the determination in step S16 is "NO", and the processes of steps S13 to S16 are repeated.

If the thief breaks open the door or opens the trunk, step S14 or
The determination in S15 is "NO", and the anti-theft alarm processing from step S17 onwards is performed. in this case,
If the answer in step S14 is "NO", that is, if it is detected that the door lock of the opened door is still set to the locked state even if the door is detected to be closed and opened in the theft alarm state, then "NO" is returned in step S14a. YES” and step
The process does not proceed to the theft prevention alarm processing after S17, but returns to step S13. As a result, even if, for example, the keyless lock by the driver fails and the door is momentarily closed and then opens to the ajar state, the theft alarm process will not be executed by mistake. It never happens.

On the other hand, if the determination is "NO" in steps S14 and S14a, or "NO" in step S15, the process immediately proceeds to the theft prevention alarm process from step S17 onwards. That is, when the controller 11 outputs a low level signal to the line d, the relay 18 is activated, and one terminal of the ignition coil 17 is grounded. As a result, the ignition pulse is no longer output to the spark plug, and therefore the engine cannot be started. As a result, even if a thief breaks into the vehicle interior and attempts to start the engine by some means,
It is impossible to start the engine, which prevents theft of the car.

At the same time, by outputting a low level signal to line a and line b, the horn 1
2 is sounded and the headlamp 13 is turned on (step S18). As a result, a third party is alerted to the theft of the car, and the theft of the car is prevented. In this case, the above alarm operation is performed for 60 seconds. This alarm time is controlled by the processing in steps S19 to S20. In other words, if the timer is not turned on (step S19), the timer starts counting (step S20), and the process continues in step S18 until the timer measures 60 seconds.
processing is performed. Here, when the process of step S18 is performed for the above-mentioned 60 seconds, the timer is reset via step S21 (step S22).
Then, a high level signal is output to line a and line b, so that the alarm of the horn 12 and the lighting of the headlamp 13 are stopped (step
S23). In this way, after the alarm processing is stopped,
5 seconds after steps S24 to S26, the above steps are executed.
Return to S2 processing. In other words, if the timer is not turned on (step S24), the timer starts counting operation (step S25), and when the timer measures 5 seconds (step S26), the above-mentioned step S2 is started.
Return to processing. If the door is still open or the trunk is open, the determination in step S14 or S15 is "NO", and the process returns to steps S17 to S26.
The process is repeated. In other words, if a door or trunk is forcibly opened, the engine will not be able to start, and the horn 12 and headlight 13 will sound or turn on for 60 seconds at 5-second intervals to warn a third party of theft. I can let you know.

On the other hand, even if no object is inserted into the door keyhole and the door and trunk are closed, the ultrasonic sensor 1
If the receiver 10b detects a change in the reflected wave as 0, it is assumed that a thief has entered the vehicle interior by some means, and the alarm processing from step S27 onwards is performed. That is, similar to step S17, the engine is disabled from starting (step S27). Next, a low level signal is output to line a and line b, so that the horn 12 is sounded and the headlamp 13 is turned on. This allows a third party to be alerted to the theft of the car. Here, the above-mentioned warning is given for 10 seconds, and the warning time is controlled by the processing in steps S29 to S31. In other words, if the timer is not turned on (step S29), the timer starts counting (step S30), and the above steps continue until the timer measures 10 seconds.
The process of S28 is performed. And by the timer
When 10 seconds have been counted (step S31), line a
Then, a high level signal is output to line b, and the operation of the horn 12 and headlamp 13 is stopped (step S32). Thereafter, the process returns to step S2. If the thief has still entered the vehicle interior, the determination in step S16 is ``YES'', and the processes in steps S27 to S32 are repeated. In other words, if the ultrasonic sensor 10 detects that a thief has entered the vehicle interior with no object inserted into the keyhole of the door and the door and trunk are closed, the horn 12 A 10-second warning process is performed by the head lamp 13, and if the thief continues to enter after the 10-second warning, the 10-second warning process is repeated.

On the other hand, the operation when the owner of the car inserts the key into the keyhole of the door to unlock the door and enter the vehicle interior will be explained.

In this case, since the key is inserted into the keyhole of the door, the determination in step S13 is ``YES'', and the process proceeds to step S33. If the object inserted into the keyhole of the door is an ignition key, the door is unlocked, so the determination in step S33 is "NO" and the process proceeds to step S34. If the engine cannot be started (step S34), the engine startability is canceled (step S35). That is, by outputting a high level signal to line d, the relay 18 becomes inactive, one terminal of the ignition coil 17 is connected to the distributor, and the engine can be started. Further, when the horn 12 and the headlamp 13 are in the operating state (step S36), the horn 12 and the headlamp 13 are activated.
operation is stopped (step S37). this is,
This is done by outputting high level signals to line a and line b.

That is, when the owner of the car inserts the ignition key into the keyhole of the door to unlock the door and enter the vehicle interior, if an alarm process is already in progress, the alarm operation is stopped. Furthermore, if the alarm process is not being performed, "NO" is determined in steps S34 and S36, and the process returns to step S1.

Also, if something other than the ignition key is inserted into the key hole of the door, the above step S13
However, since the door is not unlocked, the determination in step S33 is ``YES'' and the process returns to step S13. In other words,
In this case, the processes of steps S34 to S37 are not performed.

Next, a vehicle theft alarm system according to a second embodiment of the present invention will be described with reference to FIGS. 4 to 6. In FIG. 4, numeral 21 is a controller that performs overall control of the apparatus. The control performed by this controller 21 will be described later using the flowchart shown in FIG.

In FIG. 4, battery power B is input to the controller 21. In FIG. Also, the signal ACC becomes active when the ignition key switch is set to the "ACC" position, and the signal IG becomes active when the ignition key switch is set to the "IG" position.
are respectively input to the controller 21. In addition, DLSW1 is the driver's door lock switch,
DLSW2 is the passenger door lock switch, DLSW
3 and DLSW4 are rear seat door lock switches, which are opened when the door is locked. Further, DSW1 is a driver's door switch, DSW2 is a passenger's door switch, DSW3 is a rear seat door switch, and DSW4 is a rear seat door switch, which are opened when the door is closed. In addition, TRSW is a trunk switch,
FDSW is an engine hood switch, which opens when closed. Also, KULSW1
is a driver's key unlock switch that detects when the driver's door is unlocked, and KULSW2 is a passenger's key unlock switch that detects when the passenger's door is unlocked.
KULSW3 is a trunk unlock switch that detects unlocking of the trunk, and each switch is closed when the trunk is unlocked.

By the way, 22 is a horn, and battery B power is supplied to this horn via a relay switch 23S in a horn relay 23. One end of the relay coil 23l of the relay 23 is connected to the battery B power source and the indicator lamp 20, and the other end is connected to the controller 21 via line a and is provided on the handle. Connected to horn switch HSW. Further, 24 is a headlight, and battery B power is supplied to this headlight via a relay switch 25S in a headlight relay 25. One end of the relay coil 25l of the relay 25 is connected to the battery B power source and the indicator lamp 20, and the other end is connected to the controller 21 via line b and is provided on the handle. Connected to headlight switch HDSW. moreover,
26 is a tail light, and this tail light has a relay switch 2 in a tail light relay 27.
Battery B power is supplied via 7a. Further, one end of the relay coil 27l of the relay 27 is connected to the battery B power source and the indicator lamp 2.
0, and the other end is connected to the controller 21 via line c, and is also connected to a tail light switch TLSW provided on the steering wheel. Furthermore, 28 is the starter motor 2 when the intrusion of an illegal intruder is detected.
This is a starter inhibit relay to prevent the engine from being forced to start. This relay 28
The normally closed contact 28t of the relay switch 28S is connected to the start position ST of the ignition switch. A fixed contact of the relay switch 28S is connected to the starter motor 29. Further, one end of the relay coil 28l of the relay 28 is connected to the battery B power source and the indicator lamp 2.
0, and the other end is connected to the controller 21 via line d. Further, the other end of the indicator lamp 20 is connected to the controller 21 via line e.

Next, the operation of the second embodiment of the present invention configured as described above will be explained. The flowchart shown in FIG. 5 shows the processing performed by the controller 21. First, initialization is performed (step S41). Next, it is determined whether the front seat door is open based on the signal from the door switch DSW1 or DSW2 (step S42). Here, if it is determined that the front seat door is open, the lock switch DLSW will check whether the front seat door is locked or not.
1 or DLSW2 (step S43). When the front seat door is locked, a timer (not shown) starts to measure time, line e is set to low level under the control of the controller 21, the indicator lamp 20 is turned on, and the burglar alarm system is put on standby. It is reported that this is the case. For example, when the driver opens the driver's seat door, locks the door, and closes the door when getting out of the vehicle, the vehicle is placed in a standby state.

This standby state is maintained for 20 seconds,
The time is counted by the timer. In this standby state, if a condition for canceling the system occurs, the system is canceled (steps S45, S46). The release conditions for this system are when the signal ACC or IG is turned on, when the front seat door is unlocked, or when the door changes from open to closed to open while the door is locked.

By the way, if the cancellation condition does not occur during the 20 seconds of standby mentioned above, (step
S47), and the process proceeds to steps S48 and subsequent steps. Were all doors locked in the process of step S48?
The determination is made based on the signals from DLSW1 to DLSW4. When it is determined that all the doors are locked, the indicator lamp 20 is turned off under the control of the controller 21 to notify that the system has entered the alert state (step S49). If a door or trunk is opened with something other than the key after entering the alert state, an alarm will be issued, but before that, it will be detected that all doors have been closed. Such a warning will be issued. That is, it is determined whether an alarm has already been issued (step S50), and if no alarm has already been issued, it is determined whether the signal ACC or the signal IG is (active) (step S51). signal
If ACC or signal IG is on (active), the alert state of the system is canceled and the process returns to step S42 (step S52). Above steps
In S51, if the signal ACC or the signal IG is not turned on, if it is detected from the signals from the door switches DSW1 to DSW4 that all the doors are closed, the cause of the theft alarm is determined by the determination from step S54 onwards. A warning will be issued if this occurs. In other words, even if the alarm state is reached in step S49, the actual alarm will not start until all doors are closed.

Thereafter, in step S54, it is determined whether the trunk has been opened with the key based on the signals from the trunk switch TRSW and the trunk key unlocking switch KULSW3. For example, such a case occurs when a driver takes out luggage from the trunk after getting off the vehicle. In such a case, no warning is issued and the alert state is maintained. Then, the trunk switch TRSW detects whether the trunk is closed (step S55), and if the trunk is open, the key unlock switch KULSW 1 or 2 detects whether the front seat door has been unlocked with the key.
The decision is made based on the signal from
S56). If the front seat door is unlocked with the key, the system is canceled and the process returns to step S42 (step S57). If the front seat door is not unlocked with the key, the process from step S55 onward is repeated until the trunk is closed, and when the trunk is closed, the process returns to step S50. By the way, if it is determined in step S54 that the trunk has not been opened with the key, it is determined whether the front seat door has been opened with the key based on the signal from the key unlock switch KULSW1 or 2 (step S58). If the door is opened with the key, the system is released and the process returns to step S42 (step S59).

On the other hand, if the front seat door is not opened with the key, it is determined whether the hood or the trunk has changed from closed to open (step S60). This is done by detecting signals from the hood switch FDSW and trunk switch TRSW. If the determination in step S60 is ``YES'', an alarm is started (step S61). That is, the headlight 24 is turned on, the horn 22 is blown, and the starter motor 29 is interlocked. In other words, the line b is set to low level at predetermined intervals under the control of the controller 21, and the relay coil 25
l is energized and de-energized, the relay switch 25a is closed and opened, and the headlight 24 is blinked.
Line a is set to low level and relay coil 23
l is energized, relay switch 23s is closed, horn 22 is blown, line d is set to low level, relay coil 28l is energized, relay switch 28s is opened, and the ignition key switch is placed in the "ST" position. Even if starter motor 2
9 cannot be driven. Thereafter, it is determined whether the door or trunk has been opened with the key or not based on the signals from the key unlock switches KULSW1-3 (step S62). If the determination in step S62 is ``YES'', the alarm started in step S61 is stopped (step S63) and the system is also canceled (step S64).

On the other hand, if the door or trunk was not opened with the key, the alarm started at step S61 will continue for three minutes, and that time is counted at step S65. If three minutes have elapsed, the alarm started in step S61 is stopped (step S66). Thereafter, the process returns to step S50.

By the way, before 3 minutes have passed, the step
If something other than the one that changed from closed to open in S60 changes from closed to open (step S67), the above step
Returning to S61, an additional 3-minute warning will begin. By the way, if the determination in step S67 is "NO", the process returns to step S62.

On the other hand, if the determination in step S60 is "NO", the door switches DSW1 to DSW are checked to see if the door has changed from closed to open as shown in FIG.
The decision is made based on the signal from step 4 (step
S61a). If the determination in step S61a is "NO", the door remains closed, and the process proceeds to steps S50 and subsequent steps to continue the alert state. On the other hand, if the determination in step S61a is "YES", that is, the door changes from closed to open as shown in a in FIG. Judgment will be made based on In other words, it is determined whether the door is locked at point b (step
S61b). If "YES" is determined in this step S61b, the driver has failed in the keyless lock and the door is still in the locked state, and it is determined that the door is not fully closed and the door is ajar, so the alarm in step S61 is activated. is not performed, and the process returns to step S45.
On the other hand, if the determination in step S61b is "NO", it is determined that the thief unlocked the door lock with something and opened the door, and the process proceeds to step S61.
Proceed to , and the alarm will start.

Further, after the alarm is stopped in step S66, the process returns to step S50, but since the alarm has already been issued, the answer is ``YES'' in step S50, and the process proceeds to steps S68 and subsequent steps. The key unlock switch KULSW1 indicates whether the front seat door or trunk was opened with the key.
The decision is made based on the signals from ~3 (step
S68). If the door is opened with the key, the system is released and returns to step S42 above (step
S69). On the other hand, if the front seat door or trunk has not been opened with the key, it is determined whether any of the doors, hood, or trunk has changed from closed to open (step S70). This is a door switch
This is done by detecting signals from DSW1-4, hood switch FDSW, and trunk switch TRSW. “YES” in this step S70
If it is determined that
S61). In this way, theft can be prevented by giving an alarm when an illegal intruder attempts to break in.

Therefore, according to the theft alarm device having the above configuration, it is not only possible to start the theft alarm operation in response to the keyless lock operation by the driver, detect the intrusion of a thief into the vehicle interior, and issue an alarm. Even if a door close → open is detected during theft alarm operation, if the door lock of the opened door is in the lock set, the system is configured so that the theft alarm process does not proceed, so that the keyless lock door fails to close. Even if the door moves from closing to opening, the anti-theft alarm will not be activated by mistake.

[Effect of idea]

As described above, according to this invention, the theft alarm operation is started by keyless lock operation according to the driver's intention, and when a certain period of time has elapsed after the door lock operation when opening the door, all doors are further closed. After this door is closed, even if the door is detected to be closed and then opened, the door will still be locked, indicating that the door is not fully closed and the door is ajar. The structure is configured so that the theft alarm process will not proceed if the theft alarm is detected, so if the door is detected to be closed and then opened due to a keyless lock failure, the theft alarm process will be executed and a false alarm will not occur. A burglar alarm system can be provided.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing a vehicle theft alarm system according to a first embodiment of the present invention, FIG. 2 is a diagram showing how the ultrasonic sensor of the theft alarm system is installed, and FIG. 3 is a diagram showing the theft alarm system. Flowchart showing the operation of the device; FIG. 4 is a circuit diagram showing a vehicle theft alarm device according to the second embodiment of the invention; FIG. 5 is a flowchart showing the operation of the second embodiment; FIG. FIG. 2 is a diagram showing the states of the door lock SW and the door SW. 10... Ultrasonic sensor, 11... Controller, 12... Horn, 13... Head lamp, 1
7...Ignition coil, 19...Indicator lamp, DKSW1, DKSW2...Switch for door key hole, DLSW1 to DLSW4...Switch for door lock, DSW1 to DSW4...Switch for door.

Claims (1)

[Scope of utility model registration request] A vehicle theft alarm system that detects the intrusion of a thief into a vehicle and issues an alarm includes a door opening/closing detection means for detecting opening/closing of a door, a door lock detection means for detecting an unlocking of the door, and a door opening/closing detection means for detecting door opening/closing. After a predetermined period of time has elapsed since the opening of the door is detected and the door lock detection means detects that the door is locked, the intrusion of the thief is detected when the door opening/closing detection means detects that all the doors are closed. Even if the door opening/closing detection means detects that the door is opened after the theft alarm start control means starts intrusion detection, the door lock detection means detects that the door continues to be locked. A theft alarm device for a vehicle, characterized in that it is equipped with a false alarm prevention means that determines that the door is ajar and is incompletely closed, and does not proceed to a theft alarm process.