JPS5826208Y2 - Anti-theft device for motorcycles - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a device for preventing theft of a two-wheeled vehicle.

Unlike passenger cars, motorcycles cannot have their doors locked, so they are easily accessible near the ignition switch, and can be kicked started by simply connecting the power cable directly to the ignition circuit without an ignition key. Theft is much more common than in Japan.

By the way, statistically speaking, the most common cause of theft is directly connecting the power line to one ignition circuit.

Normally, the direct connection method described above is to cut the ignition switch wire harness and connect the power wire directly to the ignition coil, or pull out the ignition switch connector inside the headlamp housing, which is easy to remove, and connect the wire harness connector terminals. This was done by short-circuiting with lead wires, etc.

This idea was created by focusing on the points mentioned above.

The object is to provide a theft prevention device for a two-wheeled vehicle in which an alarm is activated to notify theft when a wire harness including an ignition circuit is cut or a connector is disconnected.

Next, an embodiment of this invention will be described with reference to the drawings.

1 is an ignition switch whose contacts are closed by inserting a key; 2 is a battery loaded on a motorcycle; an ignition coil including 31 contact points; 4 is a theft detection circuit according to this invention; 5 is a battery 2, an ignition This connector connects the primary coil of the coil 3 and the theft detection circuit 4 to the ignition switch 1 via a wire harness 6 consisting of a power line L1, a signal 7wL2° ignition line L3.

The theft detection circuit 4 includes an alarm B such as a buzzer, a thyristor Q,
It is composed of a transistor T, a diode D, resistors R1 to R4, and a capacitor C.

Note that one end of the alarm B is directly connected to the battery 2.

Further, the details of the circuit configuration will be explained in detail below.The signal line L2I is connected to the base of the transistor T via a resistor R1 and a diode D.

Further, a series circuit of an alarm B and a thyristor Q is connected in parallel to the battery 2, and a resistor R2 is connected to the alarm B.

A series circuit of a resistor R3 and a capacitor C is connected between the anode and the gate of the thyristor Q, and a resistor R4 is connected between the gate and the cathode.

And the collector/emitter 1 of the above transistor T
1 is connected to the anode and cathode of thyristor Q.

Further, FIG. 2 shows another embodiment of the theft detection circuit 4, in which the first
Thyristor Q in Figure ◆ (This is connected to a replacement transistor T1; the other parts are the same as the parts in Figure 1, and the same reference numerals indicate the same parts.

Next, the operation will be explained based on the circuit configuration described above. In the signal state, battery 2 → power line L1 → connector 5 → ignition switch 1 → connector 5 → signal line L2 → resistor R1 → diode A current flows through D to the base of the transistor T, and the transistor T is turned on.

Therefore, the current from the battery 2 flows to the ground via the resistor R2 and the transistor T, so the alarm B does not operate.

If the thief disconnects the connector 5 or cuts the wire harness 6, the base current to the transistor T due to the above closed loop is cut off, so the transistor T is turned off.

Here, current flows in a closed loop of battery 2 → resistor R2 → resistor R3 → capacitor C → resistor R4 → ground, so
A current flows through the gate of thyristor Q, and thyristor Q is turned on.

Therefore, current flows to alarm device B and issues an alarm.

Note that once the thyristor Q is turned on, it remains on, so even if the connector 5 is connected, it continues to operate until the alarm B is removed from the battery 2.

In Fig. 2, a transistor T1 is connected in place of the thyristor Q, but in this case, the connector 5 is disconnected,
Alternatively, if the wire/1-ness 6 is disconnected, the transistor T is turned off, so the transistor T1 is turned on and the alarm B operates, but the connector 5 is connected again or the wire harness 6 is connected. As a result, the transistor T is turned on, the transistor T1 is turned off, and the alarm B becomes inoperable.

As mentioned above, this idea works by connecting the signal line to the ignition switch's power line through the connector, and then disconnecting the connector or cutting the wire harness to cut off the power supply to the signal line, which will cause the switching circuit to shut down. Reverse the alarm (this is the one that is energized, so
With a simple structure, an alarm can be issued in the event of theft due to uncoupling of the connector or cutting of the wire harness. Therefore, it is possible to effectively prevent theft with an inexpensive device. Since there is no need for special operations to set the set, it can prevent forgetting to set the set, etc., and since there is no special work on the outside, it can make thieves wary and destroy the anti-theft device. It has the effect of reducing the chance of being manipulated into being incapacitated.

[Brief explanation of the drawing]

The figures show an embodiment of the anti-theft device for a two-wheeled vehicle according to this invention, FIG. 1 is an overall circuit diagram, and FIG. 2 is a circuit diagram showing another embodiment of the theft detection circuit according to the above. 1...Ignition switch, 2...
・Batch Lee, 4...Theft detection circuit, 5...
...Connector, 6...Wire harness,
L...Power line, L2...Signal line, B...
...Alarm.

Claims (1)

[Scope of utility model registration request] The signal wire connected to the power supply wire inside the ignition switch is pulled out together with other wire harnesses through the connector, and the signal wire is connected to the transistor, etc., which is turned on unless the wire harness is disconnected or the connector is released. A first switching element is connected, and a second switching element such as a cyrisk which turns on when the first switching element goes off is connected, and an alarm is connected as a load of the second switching element. Anti-theft device for motorcycles.