JPS5830686B2 - detection device - Google Patents

Description

[Detailed Description of the Invention] The present invention includes a rotary magnet, a reed switch,
Regarding a detection device configured with a drive magnet and used, for example, as a security switch to detect the opening of a door, the object thereof is to provide a detection device with high sensitivity.

In the conventional detection device of this kind, as shown in FIG. 1, a bias magnet 2 is added to a reed switch 1 to maintain the reed switch 1 in an on-operation state, and a drive magnet 3 approaches the reed switch 1 to turn the reed switch 1 on. However, the present invention provides a detection device with improved detection sensitivity by further improving this detection device, thereby providing a detection device that is extremely convenient for crime prevention devices. .

Hereinafter, an embodiment of the detection device of the present invention will be described with reference to FIGS. 2 and 3, which are denoted by the same reference numerals as those of the conventional example.

In the figure, 1 is a reed switch with a reed piece 1a,
1a.

Reference numeral 6 denotes a rotary magnet, which is a permanent magnet whose magnetic flux axis connecting the north and south poles is α, and is rotatably mounted on the shaft 5.

Let M be a line that passes through the axis 5 and intersects perpendicularly to the longitudinal axis of the reed switch 1, then the distance between the points P and M is a predetermined distance H.

Assuming that the angle between the magnetic flux axis α of the rotary magnet 6 and the line M is θ, the angle change θ is set within the range of 0 degrees < θ < 90 degrees.

For this purpose, stop bodies 8a, 8b are provided.

Reference numeral 3 denotes a drive magnet, which is composed of a permanent magnet whose magnetic flux axis connecting the north pole and the south pole is β.

This drive magnet 3 is fixed to, for example, a door or a sliding door, and moves according to the movement Q of the door or sliding door.

Next, the positions of the stop bodies 8a and 8b will be explained.

The position of the stop body 8a is such that the drive magnet 3 is in the second position.
As shown in Figure a, when the rotary magnet 6 is separated from the container 7, it is no longer affected by the drive magnet 3, so the magnetic flux of the drive magnet 3 is attracted to the magnetic pole pieces 1a, la of the reed switch 1, and the rotary magnet 6 is placed in a stable position. That is, it is rotated to a position where the magnetic flux emitted from the N-pole surface of the rotary magnet 6 takes the closest distance to the reed piece 1a of the reed switch 1.

Therefore, the stop body 8a is connected to the rotary magnet 6.
When it is attracted by the magnetic flux of the reed piece 1a and rotates (in the A direction), it comes into contact with this stopper 8a and is stopped.

If the magnetic flux axis α of the rotary magnet 6 and the magnetic flux axis β of the drive magnet 3 are on the same line, it will be stabilized at a position where θ=O.

However, if θO is used, then when the drive magnet 3 approaches as shown in Figure 2, it will no longer necessarily rotate in the direction of arrow B. Therefore, the rotary magnet 6 must be stopped at a position where the angle θ does not become zero. body 8
A is provided.

Then, the magnetic flux axis α of the rotary magnet 6 and the line M
Since the angle θ formed by the rotary magnet 6 is small, most of the magnetic flux that is captured by the lead pieces 1a and la of the rotary magnet 6 and housed in the lead piece 1a exits from the lead piece 1a and enters the S pole. The dimension H is determined so that the shaft 5 is located at a position that constitutes.

Next, the position of the stop body 8b will be explained.

That is, when moving the drive magnet 3 in a direction approaching the container 1 (see FIG. 2), the S pole of the drive magnet 3 and the S pole of the rotary magnet 6
Since the poles are opposed to each other, a repulsive force is generated between them, and the rotary magnet 6 rotates in the direction B as shown in FIG.

If the rotary magnet 6 is moved so that the angle θ between the magnetic flux axis α and the line M exceeds 90 degrees, the drive magnet 3 will move away from the container 7 as shown in FIG. Since it is no longer necessarily rotated, a stop body 8b is provided to stop the rotation within the range of the angle θ<90 degrees.

At this time, most of the magnetic flux ψ is captured by the reed piece 1a, comes out from the reed piece 1a again, and returns to the S pole, and the attractive force between the reed pieces 1a becomes smaller. The dimension H is selected such that the contact point is at a position where it is opened.

The drive magnet 3 is attached to a door or sliding door, and when the door or sliding door is closed, it approaches the detector housed in the container 7, as shown in Figure 2, and moves the rotary magnet 6 in the direction B. The rotary magnet 6 comes into contact with the stopper 8b and comes to rest. In this state, the magnetic flux of the rotary magnet 6 enters through the reed piece 1a of the reed switch 1 and exits from the reed piece 1a, causing the rotary magnet 6 to come into contact with the stop body 8b and stand still. Since the reed switch 1 returns to the S pole, the contact point of the reed switch 1 is open.

When the encased drive magnet 3 is moved to open a door or a sliding door and is separated from the container 7 as shown in FIG. It rotates (in the A direction) to obtain a suitable position, and stops when it comes into contact with the stop body 8a.

At this position, most of the magnetic flux ψ forms a magnetic path that enters through the reed piece 1a and exits from the reed piece 1a, so that the contacts of the reed switch 1 are closed.

FIG. 3 shows another embodiment of the present invention, in which a pair of stop bodies 8a
, 8b are formed integrally with the container 7.

As described above, according to the present invention, the reed switch 1 and the shaft 5
A rotary magnet 6 that rotates around the reed switch is attached to the container 7, and the drive magnet 3 is moved toward or away from the container 7 to rotate the rotary magnet 6 in a predetermined direction. 1
In this detection device, the position of the shaft 5 is shifted by a predetermined distance H in the longitudinal direction of the reed switch 1 from a point P, which is the longitudinal center of the reed switch 1, and A pair of stop bodies 8a and 8b are provided for regulating the angle θ formed by a line M passing through the shaft 5 and orthogonal to the longitudinal axis of the reed switch 1 and the magnetic flux axis α of the rotary magnet 6 to 0 degrees <θ<90 degrees. Since the detection device is provided, the contacts of the reed switch 1 can be closed or opened by the magnetic flux of the rotary magnet 6 rotatably supported near the reed switch 1 by approaching or separating the drive magnet 3. An extremely sensitive detection device is obtained.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a conventional detection device. 2 and 3 show an embodiment of the detection device of the present invention, FIGS. 2a and 2b are operation explanatory diagrams of one embodiment, and FIG. 3 is a front view showing another embodiment. 1...Reed switch, 1a, 1a...
・Lead piece, 3...Dry magnet 3.5
...shaft body, 6 ... rotary magnet, 7 ... container, 8a8b ... stop body.

Claims (1)

[Claims] 1 Attach the reed switch 1 and the rotary magnet 6 that rotates around the shaft 5 to the container T,
In the detection device, the rotary magnet 6 is rotated in a predetermined direction by moving the drive magnet 3 toward or away from the container 7 to close or open the contacts of the reed switch 1. The position is shifted by a predetermined distance H in the longitudinal direction of the reed switch 1 from a point P which is the center in the longitudinal direction of the reed switch 1, and the position passes through the axis 5 and the reed switch 1
A detection device characterized in that a pair of stop bodies 8a and 8b are provided for regulating the angle θ between a line M orthogonal to the longitudinal axis of the rotary magnet 6 and the magnetic flux axis α of the rotary magnet 6 to 0 degrees < θ < 90 degrees. .