JPH0587415B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle anti-theft device that combines a key body having a light emitting element and a steering lock having a light receiving element.

[Conventional technology]

Conventionally, the number of keys for vehicles such as automobiles has been determined by the type of groove formed in the key.
Therefore, it is difficult to increase the number of keys based on the types of grooves alone, and there is also a possibility that locks may be unlocked by picking (illegal means).

Therefore, in recent years, instead of determining the number of keys only by the groove of the key, other discrimination means have been incorporated into the key itself, and the lock can be unlocked when both the groove and other discrimination means match. There are anti-theft devices for vehicles, such as those disclosed in U.S. Patent No.
Exists as No. 4148372.

In addition, as a condition for starting the engine, this invention requires that the key is inserted into the steering lock and rotated to the starting position, and that the resistance value of the resistance pellet embedded in the key is the resistance value preset in the vehicle. The engine will start when the conditions match.

[Problem that the invention seeks to solve]

By the way, in the conventional technology, by inserting the key into the steering lock and turning the ignition switch to the ON position, it is confirmed that the key grooves match, and electricity is supplied to various electrical systems. A measuring device installed inside the steering lock measured the resistance value of the resistor pellet embedded in the key and confirmed that it matched.

However, although the resistor pellet is embedded in the key, its surface is exposed to the outside, so its resistance value fluctuates to some extent due to the influence of temperature, humidity, etc.

Therefore, it is necessary to ensure a certain tolerance range for the resistance value (for example, in the case of keys manufactured by GM,
With a resistance pellet of 887Ω, the lower limit is 852Ω and the upper limit is 942Ω), it was not possible to create many types of resistance pellets, and it was not possible to obtain many key differences.

Therefore, in view of the above-mentioned conventional problems, the present invention has been developed by inserting a key into the steering lock and rotating the ignition switch to the ON position, thereby aligning the key grooves and using another unique feature provided on the key. The purpose of the present invention is to provide a vehicle anti-theft device which determines whether data matches and which can obtain many different keys.

[Means for solving problems]

In order to achieve the above object, the vehicle anti-theft device according to the present invention is provided by inserting the key into the steering lock and rotating the ignition switch to the ON position, thereby aligning the key grooves and attaching the key to the key. In the anti-theft device for a vehicle, a terminal connected to a power source is provided in the key hole of the steering lock, and a light receiving element is provided on the front surface of the key hole insertion surface. .

A key body is constituted by a key part in which the key groove is formed and a mold part which is a grip part, and an electrode is provided in a part of the mold part to be inserted into the key hole, and is in contact with the terminal. A light emitting element is provided at a portion facing the light receiving element when rotated, and is operated by power supplied through the electrode, and the light emitting element emits a pulse signal according to a code signal set in advance in a memory circuit. A light emitting circuit for transmitting light to the light source is provided in the mold portion.

A light receiving circuit is provided to receive a pulse signal from the light receiving element of the steering lock, and the light receiving circuit determines whether or not the pulse signal matches a preset code signal, and when they match, the starter or engine controller, etc. make the load ready for operation.

[Effect]

In the above configuration, when the key is inserted into the steering lock, the electrode provided on the key and the electrode provided inside the steering lock come into contact. In this state, if the key is a valid key, the ignition switch can be turned to the ON position, and power is then supplied to the light emitting circuit of the key body via the electrodes. On the other hand, power is also supplied to the light receiving circuit inside the steering lock and the light receiving circuit becomes ready to receive light.

When power is supplied, the light emitting circuit causes the light emitting element to blink using a pulse signal from the memory circuit based on a specific code unique to the key. When the light receiving circuit receives this pulse signal, it determines whether it matches an internally preset code signal, and if it matches, it starts the starter.

[Embodiments of the invention]

Next, one embodiment of the present invention will be described with reference to the drawings.

Fig. 1 shows an ignition key body, where 1 is a key body in which a groove 1a corresponding to a vehicle key is formed, and electrodes 1b are attached to opposing parts of the base of the key body.
are formed in an insulated state. Moreover, a molded part 1c which is a grip part is integrally formed in this key body 1, and a light emitting element 1d which is a pair of light emitting diodes is buried in the key plate side with a part exposed. A light emitting circuit 3 shown in FIG. 3 is also embedded inside.

Fig. 2 shows a steering lock on the vehicle side into which the key body 1 described above is inserted, 2 is the steering lock body, a key hole 2a into which the key body 1 is inserted, and a part facing the key hole 2a. terminal 2b
is provided. When the key body 1 is inserted into the key hole 2a, the groove of the key body 1
When 1a and the key of the steering lock body 2 match, the key body 1 can be rotated, the terminal 2b and the electrode 1b of the key body 1 are connected, and power is supplied to the light emitting circuit 3. be. Further, a light receiving element 2c is attached to the ignition ON position of the steering lock body 2, and is adapted to receive light emitted by the light emitting element 1d of the key body 1.

A light receiving circuit 4 is connected to the light receiving element 2c, and determines whether a signal from the light receiving element 2c is a signal from the key of this vehicle.

Next, the light emitting circuit 3 embedded in the mold part 1c described above will be explained with reference to FIG.
b is the electrode of the key body 1 described above, and 1b is also a light emitting diode. The pole changing circuit 3a is connected to 1b, and when the key body 1 is inserted into the steering lock body 2 as described above and the electrode 1b and terminal 2b are connected, the voltage becomes 12V.
However, since the + and - poles for the light emitting circuit 3 are not constant depending on the insertion direction of the key body 1, even if a voltage of opposite polarity is applied to the electrode 1b, the correct voltage will not be applied to the circuit 3. This is to ensure that the voltage is applied. That is, even if the key body 1 is reversed 180 degrees and inserted into the steering lock body 2, the correct voltage is applied to the light emitting circuit. Note that a diode rectifier circuit, for example, is used as this polarity conversion circuit.

A control circuit 3b is connected to the pole conversion circuit 3a,
A transistor 3d is controlled on/off by a signal from a memory circuit 3c, which will be described later, to cause the light emitting diode 1d to blink. A specific code, which is a pulse signal, corresponding to a specific vehicle is recorded in the memory circuit 3c.

Therefore, when the key body 1 is inserted into the hole 2a of the steering lock body 2 and power is supplied to the light emitting circuit 3, the memory circuit 3c sends out a pulse signal of a specific code, and the control circuit 3b receives the pulse signal. The transistor 3d is turned on and off based on.
As a result, the light emitting element 1d blinks as the transistor 3d turns on and off.

Next, the light receiving circuit 4 connected to the steering lock body 2 described above will be explained with reference to FIG.
2b is a terminal attached to the steering lock body 2, and 2c is a light emitting diode.

4a is an ignition switch that is closed when the steering lock body 2 is rotated by the key body 1 to the on position; 4b supplies power to the terminal 2b; the signal received by the light receiving element 2c will be described later. An input/output circuit that outputs an output to the control circuit 4c and further outputs to the control circuit 4c that the ignition switch 4a is closed, and 4c connects the power to the terminal 2b when the ignition switch 4a is closed. and determines whether or not the signal from the light receiving element 2c is the same as a signal preset in a storage circuit 4d, which will be described later. If they match, the transistor 4f is turned on; If not, a control circuit turns on the transistor 4e, 4d is a memory circuit in which a code unique to the vehicle is stored, and 4g is a transistor 4f.
This is a relay that is energized and its contacts are closed when it is turned on.

The transistor 4e is connected to a warning device such as a buzzer, and the contact of the relay 4g is a starter interlock relay (in automatic vehicles, the starter is operated only when the shift lever is in the barking position or neutral position). relay).

Next, the operation will be explained with reference to the flowcharts shown in FIGS. 5 and 6.

Now, when the correct key body 1 for the vehicle is inserted into the key hole 2a of the steering lock body 2, the electrode 1b of the key body 1 is connected to the terminal 2b, and when the key body 1 is rotated, the steering lock body 2 is rotated. Then, when the steering lock body 2 is turned to the on position, the ignition switch 4a is closed, and as described above, power is supplied to the terminal 2b by the control circuit 4c, and power is supplied to the electrode 1b via this. Supplied. Therefore, the light emitting circuit 3 operates and the control circuit 3b
reads the code in the memory circuit 3c and outputs a pulse signal to the transistor 3d. As a result, the transistor 3d turns on and off, causing the light emitting diode 1d to blink based on the pulse signal.

This blinking light from the light emitting diode 1d reaches the light receiving element 2c, so the light receiving element 2c outputs a pulse signal synchronized with the blinking light of the light emitting diode 1d, which is input to the control circuit 4c via the input/output circuit 4b. . Then, the control circuit 4c reads this pulse signal and also reads a preset signal from the storage circuit 4d, and determines whether or not the input signal and the set signal match. the result,
If they match, an output is sent to the transistor 4f, turning the transistor 4f on.

Therefore, since the relay 4g is energized, its contacts are closed and an output is sent to the starter interrupt relay, thereby operating the starter motor.

Next, a case will be described in which the key body 1 is inserted into the hole 2a of the steering lock body 2 even though it is not the correct key.

The steering lock body 2 is rotated even if the key is picked or by an unauthorized key, but at this point,
In the case of picking, since there is no light emitting diode, the light receiving element 2c does not receive light, and therefore the light receiving circuit 4 does not perform any further operation.

On the other hand, when the steering lock main body 2 is rotated by an unauthorized key, power is supplied to the key main body 1, and the light emitting element 1d blinks in the same manner as described above. Since this blinking signal is different from the signal from the memory circuit 4d that is preset in the vehicle, the control circuit 4c determines that they do not match and outputs a signal to the transistor 4e.

Therefore, transistor 4e is turned on and drives the alarm device, causing an alarm to be generated.

In the above embodiment, the case where the engine is started has been described, but it is also possible to control loads other than the engine, such as the trunk, the retractable roof, etc.

[Effects of the Invention] As explained above, according to the present invention, unique data separate from the keyway is set by a code rather than an analog quantity, so there is no need to ensure a tolerance range, and therefore Since the number of unique data can be set according to the storage capacity of the key storage circuit, many different keys can be created. In addition, the power source for the light emission on the key side is an electrode from the steering lock.
Since it is obtained through a terminal, there are advantages such as not requiring battery replacement and miniaturization.

[Brief explanation of drawings]

The figures show an embodiment of the vehicle theft prevention device according to the present invention, in which Figure 1 is a front view of the key body, Figure 2 is a front view of the steering lock body, and Figure 3 is a light emitting device molded on the key body. FIG. 4 is a circuit diagram of the light receiving circuit attached to the steering lock body side, and FIGS. 5 and 6 are flowcharts showing the operation of the control circuit in the light emitting circuit and the light receiving circuit. 1... Key body, 1b... Electrode, 1d... Light emitting element, 2... Steering lock, 2b... Terminal, 2c... Light receiving element, 3... Light emitting circuit, 4...
Light receiving circuit.

Claims (1)

[Claims] 1. By inserting the key into the steering lock and turning the ignition switch to the ON position, it is determined whether the key grooves match and other unique data provided on the key match. The anti-theft device for a vehicle comprises a key part in which the key groove is formed and a mold part which is a grip part, an electrode provided on the mold part, a memory circuit in which a code signal is set in advance, and the electrode. a key body comprising: a control circuit that converts the code signal into a pulse signal when power is supplied through the key body; and a light emitting circuit including a light emitting element that emits light in response to the pulse signal; a terminal connected to a power source in the key hole, and a light-emitting element that is provided at a position facing the light-receiving element and receives a pulse signal from the light-emitting element when the key body is rotated to the ON position. Consisting of a steering lock equipped with a memory circuit in which a code signal is set and a light receiving circuit provided with a control circuit that determines whether or not the code signal on the key side matches the code signal on the steering lock side. An anti-theft device for a vehicle, wherein the light receiving circuit enables a load such as a starter or an engine controller to operate when the code signals match.