JPS5842566B2 - Security switch - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a security switch, and in particular,
A crime prevention switch used with a cordon wire.In other words, by installing this switch mainly outdoors and stretching a wire and setting this switch at one end, if an intruder moves or cuts the wire, the alarm device will be activated. It relates to a switch that can be actuated.

Conventional crime prevention switches of this type have combined a mechanical switch and a cordon wire, but with such mechanical switches, it is difficult to completely seal the electrical contacts. Although this type of switch is mainly used outdoors, it is difficult to make it waterproof, and it is also prone to malfunction due to the expansion and contraction of the cordon wire due to temperature differences. An object of the present invention is to eliminate the drawbacks of the conventional switch as described above, and to provide a crime prevention switch that can completely seal the electrical contacts and that does not malfunction due to the expansion and contraction of the cordon wire due to temperature differences. It is to provide.

Next, the present invention will be described in detail with regard to embodiments of the present invention based on the accompanying drawings.

FIG. 1A is a plan view showing an embodiment of a security switch for use with a cordon wire according to the present invention, and FIG. 1B is a partial cross-sectional view of FIG. 1A.

FIG. 1B shows a state in which the switch wire 100 is under tension within a predetermined value range.

The security switch of this embodiment includes a housing formed by a base plate 1 and an outer cover 2 attached to the base plate 1 via a gasket 5.

The base plate 1 is provided with a mounting plate 3 for pivoting on a shaft 4.

The inside of the housing is divided into an upper chamber and a lower chamber by a cover 6 attached to the outer jacket 2 via a packing 7.

The lower chamber is completely sealed by gaskets 5 and 7.

In the lower chamber, a reed switch 9 is completely embedded in a recessed portion of a cover 6 using an epoxy resin 8 or the like.

. Therefore, this reed switch 9 is completely sealed from the surrounding environment and has a waterproof structure.

In the upper chamber, there is a spring stopper 10a fixed to the outer cover 2.
A reed switch actuator supported so as to be elastically biased along the reed switch 9 by a spring 11a having one end attached to the spring 11a and a spring 11b having one end attached to the spring stopper 10b fixed to the outer cover 2. A magnet 12 is provided.

In the state shown in FIG. 1B, the springs 11a and 1
When the tension of 1b is balanced, the magnet 12 is in the closest position to the reed switch 9, causing the reed switch 9 to be in the first state, ie, the state in which no alarm signal is generated.

The upper chamber is further provided with a slider 13 which is elastically biased by a spring 14 in a direction opposite to the direction in which the switch wire 100 is pulled.

The slider 13 is provided with a pin 15 for attaching the switch wire 100.

The other end of the switch wire 100 is provided with a hook 102 for connecting a cordon wire.

The jacket 2 is provided with an opening provided with a bush 16 for drawing out the cordon wire 100 to the outside of the jacket.

The slider 13 further includes a first protrusion 13a as a first engagement member that can engage one side wall 12a of the magnet 12, and a second protrusion 13a that can engage the opposite side wall 12b of the magnet 12. Second protrusion 13b as an engaging member
is provided.

FIG. 1B shows a case where the switch wire 100 is under tension within a predetermined value range, and in this state,
One side wall 12a of the magnet 12 and the first protrusion 13
A distance t1 between the side wall 1 on the opposite side of the magnet 1120
A distance 4 is left between 2b and the second protrusion 13b.

When the switch wire 100 is stretched, the distance t1 and the effect of expansion and contraction of the wire due to temperature difference (if the cordon wire connected to the switch wire 100 is an 8 m stainless steel wire, at -20°C to 50°C) 9.2rran
(expansion/contraction) and prevent malfunctions caused by this.

Next, the operation of the security switch of the present invention as shown in FIG. 1 will be described in detail with reference to FIGS. 2A, B, and C.

FIG. 2A schematically shows the initial state of the security switch of the present invention, and when there is no tension on the switch wire 100, the slider 13 is moved as shown in the figure by the biasing force of the spring 14. is pushed farthest to the left.

In this state, the magnet 12 is located at the first position of the slider 13.
The spring 11a is engaged by the protrusion 13a of the spring 11a.
and 11b to the left and away from the reed switch 9, and the reed switch 9 is in the second state, the off state in this row.

FIG. 2B schematically shows the normal state (set state) of the security switch of the present invention, in which one end of the cordon wire 100a is fixed and the other end is connected to the switch wire 100a.
The switch wire 10 is connected to the hook 102 at one end of the switch wire 10.
Pull it to the 0 mark point 101 and set it.

In this state, the tension of the switch wire 100 is at a predetermined value, and at the point where this tension and the biasing force of the spring 14 are balanced, the slider 13 is at the center position in the housing as shown in the figure, and the first protrusion 13a and second protrusion 1
3b is not engaged with the magnet 12, and the magnet 12 is in the central position as shown at the point where the biasing forces of springs Ila and 11b are balanced, close to the reed switch 9, and the magnet 12 9 is in the first state, in this example, it is in the on state.

Due to the temperature change in such a set state, the cordon wire 1
Even if 00a expands or contracts, it is the protrusion 13 of the slider 13.
If the distance is within the spatial distance between a and 13b and the magnet 12, the magnet 12 will not be moved at all and the state of the reed switch 9 will not change, so that no false alarm will be issued.

FIG. 2C schematically shows the state of the security switch of the present invention when an abnormal state is detected.
When 00a is pulled strongly in the direction of the arrow, slider 13
is moved to the rightmost side as shown in the figure against the biasing force of the spring 14.

In this case, the magnet 12 is engaged by the second protrusion 13b of the slider 13, and is moved to the right as shown in the figure against the force of the springs 11a and 11b, and is separated from the reed switch 9. Therefore, the reed switch 9 is placed in the first state, in this example the off state, and generates an alarm signal.

On the other hand, if an intruder or the like cuts the cordon wire 100a, no tension will be applied to the switch wire 100, resulting in a state similar to the initial state shown in FIG. 2A. , the reed switch 9 is turned off and an alarm signal is generated.

In this embodiment of the security switch of the present invention, as described above, the security switch body is mounted 5 such that it can rotate about the shaft 4 relative to the plate 3.

By making the installation part flexible in this way, when the cordon wire is stretched against the security switch, the switch and the cordon wire can always be maintained in a parallel state, and the wire will not be pulled. This prevents an excessive load from being placed on the switch when the switch is in use.

[Brief explanation of the drawing]

FIG. 1 of the accompanying drawings is a plan view and a partially sectional view showing one embodiment of the security switch of the present invention, and FIG. 2 is a partial schematic diagram for explaining the operating state of the security switch shown in FIG. 1. It is. DESCRIPTION OF SYMBOLS 1... Base plate, 2... Outer cover, 3... Mounting plate, 4... Shaft, 9... Reed switch, 11a, 11b... Spring, 12... Magnet, 13 ...Slider, 13a...First protrusion, 13b...Second protrusion, 14...Spring, 100...Switch wire, 102...Hook, 100a...Caution line wire.

Claims (1)

[Scope of Claims] 1. A crime prevention switch for use with a cordon wire, which includes a housing having a mounting section, a reed switch provided in the housing, and an elastic member along the reed switch. and a slider to which the cordon wire is attached and which can be biased elastically in the direction in which the cordon wire is pulled in accordance with the tension of the cordon wire. the magnet has first and second engaging members that can be engaged with each other, and when the tension of the cordon wire is within a predetermined range, the magnet is attached to the first and second engaging members of the slider.
is located between and spaced apart from a retaining member to set the reed switch in a first state, and when the tension in the cordon wire is less than the predetermined value range, the slider is biased in one direction to cause the reed switch to be in a first state. A first engaging member engages with the magnet and biases the magnet in one direction to bring the reed switch into a second state, and when the tension of the cordon wire is greater than the predetermined value range, the slider is biased in the other direction, and the second retaining member engages with the magnet to bias the magnet in the other direction, thereby placing the reed switch in a second state. 2. The security switch according to claim 1, wherein the housing is rotatably attached to the plate.