JPH0116232Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a removal detection device for detecting removal of each device constituting a security system from an installation location.

Conventionally, when an anomaly detector or an anomaly transmitter is removed by an intruder, etc., the detection device is a detection device whose contacts turn on and off depending on the tilt of a mercury switch installed inside the casing of the anomaly detector. Or, use a magnet to turn on the reed switch contacts.
There was a detection device that turned off. However, in the case of the former type of mercury switch, detection depends on the inclination of the housing, so an intruder may intentionally remove it to prevent it from tilting, and in this case, the removal may not be detected, and the latter If a magnet is used, the magnet is attached to the mounting plate for mounting the detection device, so if the mounting plate is removed by an intruder, it will not be detected, and if the magnet is not used without the mounting plate. The method of embedding the detection device in a wall surface or the like makes construction extremely difficult, and there is also the problem that the mounting parts of the detection device, such as bolts and screws, are visible from the outside and are undesirable in terms of design. There are also other devices that use micro-switch actuators, but as mentioned above, there is a problem that the mounting plate must be removed, and there is also a method of fixing it with strong adhesive, but it is impossible to move the installation location. There was a problem.

An object of the present invention is to provide a removal detection device installed in a security system that detects the removal of the main body of each device constituting the security system by an intruder or the like, as well as the removal of its mounting plate.

Hereinafter, the removal detection device according to the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a diagram in which an abnormality detector 1 equipped with an embodiment of the removal detection device according to the present invention is attached to a wall surface 9 via a mounting plate 2, and FIG. It is a figure which shows the state removed from. In FIG. 1, the removal detection device provided inside the casing of the abnormality detector 1 includes an actuator 4 made of a spring material such as phosphor bronze to which a permanent magnet 3 is fixed, a reed switch 6, and a reed switch 6. It is comprised of a monitoring circuit 7 that detects the opening and closing of contacts, and a transmitting circuit 8 that transmits abnormalities.

After a mounting plate 2 shown in FIG. 3 is fixed to a wall surface 9 at a predetermined location with screws 5, the abnormality detector 1 is attached to the mounting plate 2 using the hook portion 11 and the tap 12 at the bottom. Since the casing of the abnormality detector is shaped to completely accommodate the mounting plate 2, the mounting plate cannot be discovered from the outside and is suitable in terms of design. In this case, the actuator 4 has a notch 1 in a part of the mounting plate 2.
0 is provided so that it is directly pressed by the wall surface 9, so that the magnet 3 fixed to the actuator 4 is placed in a position facing the reed switch 6. Therefore, during installation, the contact of the reed switch 6, which has a normally open contact, is maintained in a closed state due to the magnetic force of the magnet 3 fixed to the actuator 4. On the other hand, when the abnormality detector is removed by an intruder or the like, since the actuator 4 itself is biased toward the outside of the housing, the magnet 3 is removed from the position facing the reed switch 6 and the contact point of the reed switch 6 is removed. is open so that it is no longer affected by the magnetic force of the magnet 3. A detection signal is thereby transmitted to the monitoring circuit 7.

FIG. 4 is a diagram showing an abnormality detector equipped with another embodiment of the removal detection device according to the present invention. In this case, a plurality of combinations of actuators 4 and reed switches 6 are used, and the operation is performed in the same manner as in the first embodiment, but since a plurality of actuators are provided, the sensitivity to removal is further increased. Needless to say, the notches 10 of the mounting plate 2 in this case are cut out by the number of actuators, and instead of the notches, the portions of the mounting plate where the actuators abut may be used as openings.

The present invention greatly improves the level of security because it can detect whether each device constituting the security system is removed by an intruder or the like in any way.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an abnormality detector equipped with an embodiment of the removal detection device according to the present invention installed on the wall surface, and FIG. 2 is a diagram showing the state in which the abnormality detector shown in FIG. 1 is removed from the wall surface. FIGS. 3a and 3b are front and side views of a mounting plate for mounting the abnormality detector of the first embodiment on a wall, and FIG. 4 is a diagram showing the removal detection device according to the present invention. It is a figure showing the state where an abnormality detector provided with an example of this is installed on a wall surface. Explanation of symbols, 1... Abnormality detector, 2... Mounting plate, 3... Magnet, 4... Actuator, 5...
Mounting screw, 6... Reed switch, 7... Monitoring circuit, 8... Transmission circuit, 9... Wall, 10... Notch, 11... Hook, 12... Screw tap.

Claims (1)

[Claims for Utility Model Registration] An abnormality detector 1 having at least one reed switch 6, a monitoring circuit 7 for detecting the opening/closing of the contacts of the reed switch, and a transmitting circuit 8 for transmitting a signal from the monitoring circuit. and a mounting plate 2 installed on a mounting surface such as a wall surface 9 for mounting the abnormality detector on the mounting surface.
A removal detection device comprising: The abnormality detector is a permanent magnet 3 fixed to each of at least one actuator 4 made of a spring material, and when the abnormality detector is installed, the The reed switch is disposed at a position facing the reed switch by directly engaging with the mounting surface through the space of the mounting plate, and when the abnormality detector is removed, the reed switch is disengaged from the mounting surface. and a casing having a shape that completely accommodates the mounting plate when the abnormality detector is installed. .