JPH0427723Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an anti-theft device for preventing theft of automobile parts.

[Conventional technology]

Conventionally, to prevent theft of automobile parts such as tires, car stereos, and door locks, a switching element such as a micro switch or reed relay is connected to the tip of a signal line (wire harness) output from a controller, and the device is used to monitor the installation status of automobile parts. The switching element is turned on and off by the output of the sensor to be detected.
By turning it off, the controller detects this and detects the presence or absence of attachment of automobile parts, that is, theft.

Here, the controller performs processing at a predetermined timing according to each part, and the sensor changes the external force and magnetic force when the car part is removed.
The switching element is thereby controlled.

[Problem that the invention attempts to solve]

In such conventional devices, the signal lines are provided depending on the type of automobile parts, so that noise is likely to be generated, causing malfunctions. Furthermore, since switching elements such as micro switches and reed relays are used, they are mechanically vulnerable to unnecessary external forces (vibration) and magnetic force other than the normal sensor output. Therefore, it is necessary to take these measures both electrically and mechanically, resulting in high costs.

Furthermore, since a large number of signal lines (wire harnesses) are provided, the total weight of the vehicle increases and the entire device also becomes large-scale.

[Means for solving problems]

The present invention has been developed in view of the conventional problems as described above, and includes a plurality of light emitting means and an optical fiber whose base end is disposed in the light emitting means and whose distal end extends near each automobile part. , a light receiving means for receiving the light irradiated onto the automobile part at the base via the optical fiber, and a clock signal sequentially outputted to each of the light emitting means, which will be described later.
a timing signal generation circuit that outputs a sampling signal to the AND circuit; and an AND circuit that outputs an output when the signal from the light receiving means is not input and the sampling signal from the timing signal generation circuit is input. , a latch circuit that latches the output from the AND circuit, and an alarm means that issues an alarm using the output from the latch circuit.

[Effect]

The present invention has the above-described configuration, and a plurality of light emitting means are turned on by a timing signal from a timing signal generation circuit, and a signal is received by a plurality of light receiving means of reflected light from automobile parts via an optical fiber. and the sampling signal from the timing signal generation circuit are input to an AND circuit, and if the light receiving means does not receive reflected light from the automobile parts at the time of sampling, the latch circuit latches and drives the alarm means. This makes it possible to simultaneously monitor the theft of multiple automobile parts.

[Example of idea]

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, headlamps 3i, 3j installed in a car 5, tires 3a, 3b,
3c, 3f, door lock 3e, car stereo 3
The tips of optical fibers 2a to 2j are disposed near each automobile part such as the trunk lock 3d and the outside handle 3h. Photo sensors 4a to 4j are attached to the base end of each optical fiber, and each photo sensor is composed of a light emitting element and a light receiving element. The drive signal to the light emitting element of the photo sensor and the processing of the signal detected by the light receiving element are controlled by the controller 1, and the controller 1 has an alarm that generates an alarm when the automobile parts 3a to 3j are removed. A device 17 is provided.

In such a configuration, the photo sensors 4a to 4
A rectangular wave signal shown in FIG. 3a is sequentially supplied from the controller 1 to the light emitting element j to scan it.
The photo sensor sequentially emits light in response to this signal, and this light is guided to the optical fibers 2a to 2j, and the light is emitted at the tips of the optical fibers 2a to 2j. At this time, each auto parts 3a to 3j
If the optical fibers are properly installed, the light from the optical fibers is reflected by each automobile part, and is guided again to the optical fibers 2a to 2j and returned to the other end as shown in FIG. 3b. The light receiving element detects this light, and the controller 1 determines that each of the automobile parts 3a to 3j is in a normal state. Further, if the automobile part is removed, the light from the light receiving element passing through the optical fibers 2a to 2j is not reflected as shown in FIG. 3c, so that no light is detected by the light receiving element. Therefore, the controller 1 detects this and determines that the corresponding automobile part has been removed,
The alarm device 17 is activated to issue an alarm. Therefore, it can be recognized that the automobile part is stolen or in a stolen state.

FIG. 4 shows a specific configuration of the present invention, in which a timing signal generating circuit 7 outputs clock signals T ₁ and T ₂ shown in FIGS. 5a and 5b. clock
The duty of T ₁ is about 50%, and the duty of T ₂ is less than 50%. Further, the H level of _T2 exists during the H level period of _T1 . This clock _T1 is a decimal counter 6
clock input CLK, T ₂ is AND12
is applied to one input terminal of the . Further, the enable terminal is connected to a reference potential. Power supply +B is applied to the reset input of decimal counter 6 via key switch 11 and to the reset input of latch circuit 13. The outputs of the decimal counter 6 are connected to the light emitting diodes 9a to 9h through resistors, respectively. The light emitted from each light emitting diode is guided to optical fibers 2a to 2h, reflected by each automobile part shown in FIGS. The light is received from 10a to 10h. The light emitting diodes 9a to 9h and the light receiving diodes 10a to 10h are used in FIGS.
It constitutes the photo sensors 4a to 4h shown in the figure. The signals detected by the light receiving diodes 10a to 10h are amplified by the receiving circuits 8a to 8h, and their outputs are
Input to NOR14. The output of NOR14 is AND
12, and the output of AND12 is supplied to the input of latch circuit 13.

On the other hand, the clock T ₁ of the timing signal generation circuit 7
is the clock input CLK of the second decimal counter 15
A reset input is also provided on key switch 11.
Connected to power supply +B via. Further, a capacitor C is connected between this reset input and the reference potential to delay the reset timing.
The output of the latch circuit 13 is input to an alarm drive circuit 17 consisting of an enable terminal of a decimal counter 15, a horn SP and its drive circuit. The output of the decimal counter 15 is supplied to LEDs 16a to 16h provided corresponding to the respective photo sensors 4a to 4h.

In such a configuration, the outputs of the decimal counters 6 and 15 are scanned by the clock T ₁ (FIG. 5a) of the timing signal generating circuit 7, and the light emitting diodes 9a to 9h and the LEDs 16a to 16h are scanned.
emit light sequentially. When each automobile part is installed normally, the light from the light emitting diodes 9a to 9h is reflected by the automobile parts through the optical fibers 2a to 2h, and the light from the light emitting diodes 10a to 10h is reflected.
detected. These signals are sent to the receiving circuits 8a to 8.
Amplify it with h and input it to NOR14. Therefore, the output _T3 becomes a rectangular wave signal having an opposite phase to that of the clock _T1 , as shown in FIG _.
It is sampled by AND12 at the timing shown in FIG. 5(b) and output to the latch circuit 13. That is,
In a normal state, the output of the latch circuit 13 is at the L level, and the enable terminal of the decimal counter 15 is held at the L level.
The decimal counter 15 is scanned by the clock _T1 supplied to CLK, and the LEDs 16a to 1 are sequentially scanned.
6h is emitted, and the alarm drive circuit 17 is not driven.

However, when the automobile part is removed, the light emitted from the corresponding light emitting diodes 9a to 9h is not reflected through the optical fibers 2a to 2h, so the light is not received by the light receiving diodes 10a to 10h and no signal is output. Yotsute NOR
As shown in FIG. 5d, the output T ₃ of No. 14 is at H level during the period corresponding to the removed automobile part. The timing of the clock _T2 latches this period, and the latch circuit 13 outputs an H level. Therefore, the enable terminal of the decimal counter 15 becomes H level, corresponding to the photo sensors 4a to 4h provided on the removed automobile parts.
Scanning is stopped at the LEDs 16a to 16h, and the LEDs are made to emit light at all times. It also drives the alarm drive circuit 17 to generate an alarm sound from the horn SP.

In addition, by turning on the key switch 11, the power supply +B is turned on to the decimal counters 6, 15 and the latch circuit 1.
The signal is applied to each of the three reset terminals, and a reset is applied. At this time, the decimal counter 15 for driving the LEDs 16a to 16h is reset with a delay from the others due to the time constant of the capacitor C.

[Effect of idea]

As described above, in the present invention, the presence or absence of a plurality of automobile parts can be monitored while being scanned by a single circuit through an optical system, so it is possible to simultaneously recognize theft of a large number of automobile parts, and
It has a simple structure, can be manufactured at low cost, and has the advantage of being lightweight and compact.

[Brief explanation of drawings]

1 and 2 are diagrams showing an embodiment of the theft prevention according to the present invention, FIGS. 3a to 3c are timing charts showing input and output signals of the photo sensor shown in FIGS. 1 and 2, and FIG. FIGS. 5a to 5d are timing charts showing signal waveforms at various parts in FIG. 1... Controller, 2a to 2j... Optical fiber, 3a to 3j... Automobile parts, 4a to 4
j... Photo sensor, 6, 15... Decimal counter, 7... Timing signal generation circuit, 17... Alarm drive circuit.

Claims (1)

[Scope of utility model registration request] a plurality of light emitting means; an optical fiber having a base end disposed in the light emitting means and a distal end extending in the vicinity of each automobile part; and a light receiving means for receiving light irradiated onto the automobile part at the base part via the optical fiber. , a timing signal generation circuit that sequentially outputs a clock signal to each of the light emitting means and outputs a sampling signal to an AND circuit to be described later; It is characterized by comprising an AND circuit that sends out an output when a sampling signal from the circuit is input, a latch circuit that latches the output from the AND circuit, and an alarm means that issues an alarm using the output from the latch circuit. anti-theft device.