JPS60253674A - Tamper switch lock - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called tamper switch lock that detects the removal of a cylinder lock provided on the trunk lid or door of an automobile.

A conventional problem in theft has been that cylinder locks provided on trunk lids and doors can be illegally removed using tools.

In order to prevent such unauthorized means, we have developed a so-called tamper switch lock that senses when the cylinder lock is removed and immediately activates an alarm to sound an alarm. In order to improve this, in particular, the switching of the switch part is performed by a magnet, and the alarm is activated when the magnet closes the magnetically sensitive reed switch.

If the magnet and magnetic sensing reed switch in conventional tamper switch locks are not placed with a sufficient gap, the magnetic force of the magnet may cause the magnetic sensing reed switch to malfunction. Another disadvantage is that the entire case becomes larger.

The object of the present invention is to eliminate such drawbacks by arranging a magnet and a magnetic sensing reed switch that senses the magnet so as to face each other, and blocking the magnetism within a gap provided on the opposing surface of the magnet. The purpose is to advance and retreat a magnetic shielding plate biased by a spring, and a rotary cam fixed to the rotor can be overlapped with a fixed cam formed at the rear of the cylinder lock, and the cylinder lock device is inserted through a hole formed in the panel. The purpose is to make it easy to insert.

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

FIG. 1 is a front view of the tamper switch lock, and FIG. 2 is a vertical sectional view of the main part of the tamper switch section.

In the figure, 1 is a case body into which a cylinder lock C is attached, and two support rods 2a formed on this case body 1'',
The claw portion 2C92d of 2b is engaged with the body C' of the cylinder lock C to hold the cylinder lock C in the case body.

Further, a magnet 3 is embedded in the case body 1, and a magnetic sensing reed switch fixed to the substrate 5 with a gap t provided is disposed at a position facing the magnet 3.

A magnetic shielding plate 6 that moves forward and backward through the gap provided in this way is provided, and the magnetic shielding plate 6 and the inner wall 1' of the case body 1 are connected to each other.
The magnetic shielding plate 6 is constantly biased by a spring 7 stretched between the two, and one end 6a of the magnetic shielding plate 6 is exposed to the outside of the case body 1.

The magnetic shielding plate 6 protrudes outside the case body 1 in this way.
is pushed in by the body C' of the cylinder lock C when the cylinder lock C is attached to the case body 1.

In this way, the other end 6b of the magnetic shielding plate 6 pushed in while resisting the spring 7 enters between the magnet 3 and the magnetic sensing reed switch 4, and blocks the magnetic force of the magnet 3. In this state, an alarm (not shown) does not operate.

In addition, when the cylinder lock C is pulled out from the case body 1 in the above-mentioned state, the magnetic shielding plate 6
It moves (toward the left in Figure 2) due to the bias of . At this time, the magnetic force of the magnet 3 closes the magnetic sensing reed switch 4 and activates the alarm.

As shown in FIG. 3, a rotatable rotary cam 9 (not shown) fixed to the rotor 8 of the cylinder lock C can be rotated approximately 180 degrees. A notch hole 10 is formed in the rear part of the cylinder lock case C'' in a range of 180 degrees.

As shown in FIG. 4, the rotary cam 9 is superimposed on a fixed cam 12 fixed to the rear of the cylinder lock case C'' and a magnet 11 is fixed thereto, and a small hole (not shown) is formed in the panel. This makes it easier to insert the cylinder locking device.

As described above, the present invention allows the magnetic shielding plate to enter and retreat into the gap provided between the magnet and the magnetic sensing reed switch, thereby making it possible to downsize the case body and prevent accidental malfunctions. However, since the fixed cam and rotating cam can be superimposed, the insertion work can be performed easily and quickly.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, with the first figure being a front view and the second figure being a front view.
The drawings are a vertical sectional view of the main part of FIG. 1, FIG. 3 is a rear side view of the cylinder lock, and FIG. 4 is a perspective view of the cylinder lock device. C...Cylinder lock, C'...Cylinder lock body, C''...Cylinder lock case, 1...Case body, 3... ...Magnet, 4...Magnetic sensing reed switch, 6...
・Magnetic shielding plate, 7...Spring. Patent applicant: Kokusan Metal Industry Co., Ltd.

Claims (1)

[Claims] A tamper switch lock that detects when a cylinder lock is removed from a trunk lid or door and activates an alarm has a case body with claws formed at the ends of two support rods and a gap inside the case body. A magnet and a magnetic sensing reed switch are arranged to face each other, a magnetic shielding plate that advances and retreats within the gap and has one end facing the outside of the case body, and a spring that biases the magnetic shielding plate, and a support rod of the case body. A fixed cam is formed at the rear of the cylinder, and when a cylinder lock is fitted into the fixed cam with a rotary cam fixed to the rotor, the body of the cylinder lock comes into contact with the end of the magnetic shielding plate and the magnetism is removed. A tamper switch lock characterized by blocking magnetic force by moving a blocking plate backward against a spring.