JPS62103247A - Theft preventing device for automobile - Google Patents

Abstract

PURPOSE:To detect the application of an abnormal force onto a key cylinder with high precision by the simple and small-sized constitution by installing a conductive member which varies the resistance value when a pressure is applied onto a part of the conductive member, between the key cylinder and a chassis panel. CONSTITUTION:In a key device 3 installed onto the door of a car, an annular conductive rubber 9 is fitted onto the cylinder body 7a of a key cylinder 7, and the cylinder body 7a is inserted into an installation hole 13 on a door outer panel 11, and the key cylinder 7 is fixed by a clip 15, nipping the conductive rubber 9 between the panel 11 and the cylinder head 7c. In the conductive rubber 9, a pair of annular electrodes are buried, and said rubber 9 is constituted so that the electric resistance reduces when the rubber 9 receives a pressure from outside in theft trouble, etc. When the electric resistance (resistance value of a resistor RR) reduces below a prescribed value, a relay 29 is operated by the H-signal supplied from a comparator 27, and a theft preventing means (horn, etc.) 31 is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION 1 Description of the Prior Art 1 An example of a conventional anti-theft device for a vehicle is the one shown in Japanese Patent Application Laid-open No. 58-20544 (Anti-theft device for automobiles).

This device is used for door outer panels, 1 to 1 run lids, etc.
The key cylinder attached to the mouth body panel is equipped with a switch that can be turned on manually by pressing the key cylinder against the back of the vehicle body panel when the cylinder is knocked down, and an alarm is issued when this switch is activated. It is configured. If the key cylinder attached to the door outer panel or trunk lid is stolen, for example, a "screwdriver"
When the driver (driver) 6 forces the vehicle in the vertical direction to the extent that the vehicle body panel is deformed, the switch is turned on and the alarm device η is activated.

However, although these conventional anti-theft devices for vehicles can detect "prying" in this direction and issue an alarm, they cannot detect "prying" in other directions, such as when the entire cylinder is rotated. In order to detect 3 cycles like this, it is necessary to install a switch around the entire circumference of the cylinder (), and the device must be installed. ! 2. Becomes coarse and large.

[Object of the Invention] In view of the prior art mentioned above, the present invention provides a simple method for detecting when an abnormal force other than the force normally applied to the key cylinder is applied.
The purpose of the present invention is to provide a dual-width anti-theft device that can detect with high accuracy in a small navel configuration.

SUMMARY OF THE INVENTION 1 In order to achieve the above object, the present invention provides a vehicle anti-theft device which is provided between a key cylinder and a vehicle body panel and changes its resistance value when at least a portion of the device receives pressure. The present invention is comprised of a conductive member that causes a change in the resistance value of the conductive member, and a reporting means that reports a change in the resistance value of the conductive member.

[Embodiment of the Invention] The attached F4 drawings all show an embodiment of the present invention, in which Fig. 1 is an external perspective view of the vehicle, and Fig. 2 is an exploded view showing the mounting structure of the key cylinder to the vehicle body panel. The perspective view and FIG. 3 are side views showing the key cylinder attached to the door outer panel on the driver's seat side, taken along arrows 1--2 in FIG. FIG. 4 is a longitudinal sectional view of the conductive member (conductive rubber), and FIG. 5 shows the electric circuit.

As shown in Fig. 1, the appearance of the vehicle 1 is the same as that of a normal vehicle, and the vehicle 1 has a key device 3 for locking the door on the driver's side door, and a key device 3 for unlocking the trunk on the trunk lid. A key device 5 is provided.

As shown in FIG. 2, the key cylinder 7 of the key device 3 includes a cylindrical cylinder body 7a, a cylinder head 7C with a key insertion hole 7b in the center, and detents 7d, 7.
e, and a rotating shaft 7 that is rotated by the rotation of the inserted key.
f. Four detents 7d and 7e are provided on the outer periphery of the cylinder body 7a, and two opposing detents 7e are provided with a notch 7g.

The cylinder body 7a of the key cylinder 7 is provided with the detent 7.
Insert the annular conductive rubber cut out at positions corresponding to d and 7e. Then, the cylinder body 7a of the key cylinder 7 through which the conductive rubber 9 has been inserted is inserted into the cylinder mounting hole 13 of the door outer panel 11 cut out at positions corresponding to the detents 7d and 7e.
Spring 15a of clip 15 provided on the back side of 1
5b into the switch 79, the key cylinder 7
is fixed to the door outer panel 11.

As shown in FIG. 3, a link 17 is fixed to the rotating shaft 7f, a rod 19 is connected to this link 17, and when the rotating shaft 7f is rotated with a key inserted into the key insertion hole 7b, the link The rod 19 is pulled up via 17,
The door will be unlocked.

As shown in FIG. 4, the conductive rubber 9 has a pair of annular electrodes 9b, 9C embedded in an annular conductive rubber material 9a. A9 (1,9
e are connected to each other. These lead wires 9d and 9e are covered with the conductive rubber material 9a,
It is connected to the connector 21 shown in FIG.

The conductive rubber material 9a has the property of reducing its electrical resistance when subjected to external pressure, and when the key cylinder 7 shown in FIG. 3 is displaced relative to the door outer panel, at least a portion thereof receives pressure. This binding, electrodes 9b, 9
This will reduce the electrical resistance between e. Displacement occurs when the key cylinder is pulled to the right or pressed to the left with respect to the door outer panel 11, and is also caused by normal key operation when the key cylinder 7 is pushed up and down. If the above rotational force (twisting) is applied, it will occur in any case. In either of these cases, the electrical resistance between the electrodes 9b and 90 decreases.

As shown in FIG. 5, the electric circuit 23 includes a comparator 27 driven by an on-board battery 25, a relay 29,
Theft prevention means 31 is also included.

The non-inverting terminal (+) of the comparator 27 is connected to the intermediate connection point of two resistors R2 and R3 connected in series between the power supply terminals, and the inverting terminal (-) is connected in series between the power supply terminals. two resistors R+.

Connected to the intermediate connection point of the RR. This resistance RR is the resistance between the lead wires of the conductive rubber 9, and this resistance R
The connection point between R and the resistor R3 is connected to the power source terminal and grounded. Therefore, the comparator 27 connects the adjusted resistors R+, R2, R3 and the resistor RR of the conductive rubber 9.
In relation to this, when the resistance value of the resistor RR of the conductive rubber 9 decreases below a predetermined value, the potential of the inverting terminal (-) becomes lower than the potential of the non-inverting terminal (+), and at this time becomes a high level. Outputs an output signal S.

A transistor 33 is interposed between the relay 29 and the comparator 27, and this transistor 33 conducts when the output signal S of the comparator 27 is at a high level, and connects the coil b of the relay 29 to close the two contacts 29a of the relay. It allows current to flow. Therefore, the relay 29 closes its contact 29a when the output signal of the comparator 27 is at a high level, thereby activating the theft prevention means 31.

The theft prevention means 31 includes a horn, a headlight, a starter interlock relay, and the like.

With the above configuration, if a screwdriver is inserted into the key cylinder at 111, for example, and an unreasonable insertion pressure, "prying" or "kneading" after insertion, or a pulling force is applied to the cylinder, The conductive rubber 9 is such that the resistance RR of the electric circuit 23 is lowered to a predetermined value or less due to these abnormal pressures.
A high level signal is output from the comparator 27, which activates the two relays and activates the theft prevention means 31.

Since the resistance values of the resistors R+, R2, and R3 can be adjusted freely, the anti-theft means 31 can be activated sensitively before the door outer panel 11 is deformed.

The same applies to the key device 5 for unlocking the trunk.

In the above embodiment, the conductive rubber 9 is attached to the door outer panel 1.
Although it is provided on the outside of 1, it goes without saying that it may be provided on the inside.

Further, although the conductive rubber 9 is shown as an annular example, it does not have to be a complete annular shape, but may have a partially cut-out shape, and one piece of conductive rubber material may be placed at evenly divided positions. established,
An electrode may be embedded in each of these conductive rubber materials and these electrodes may be connected in parallel.

[Advantageous Effects of the Invention 1] As described above, according to the present invention, it is possible to highly accurately detect the application of an abnormal force other than the force normally applied to the key cylinder over the entire circumference of the key cylinder with a simple and compact configuration.

[Brief explanation of drawings]

Each of the drawings shows an embodiment of the present invention.
Figure 1 is a perspective view showing the exterior of the vehicle, Figure 2 is an exploded perspective view of the cylinder assembly, Figure 3 is a side view of the key cylinder, Figure 4 is a longitudinal cross-sectional view of the conductive rubber, and Figure 5 is the electrical It is a circuit diagram. 7... Key cylinder 9... Conductive rubber 11... Door outer panel 27... Two comparators... Relay 31... Anti-theft means patent Applicant Nissan Motor Co., Ltd. Figure 1, Figure 3 figure

Claims (1)

[Claims] an electrically conductive member that is provided between the key cylinder and the vehicle body panel and changes its resistance value when at least a portion of the electrically conductive member receives pressure; and a notification means that reports that the resistance value of the electrically conductive member has changed; A vehicle anti-theft device comprising: