JPH05182574A - Electromagnetic relay - Google Patents

Abstract

PURPOSE:To protect load equipment from a surge without providing a separate element. CONSTITUTION:An electromagnetic relay includes an electromagnet device 1, a movable contact 2 which reacts to the electromagnet device 1, a first fixed contact 3 with and from which the movable contact 2 makes contact and separates, and a second fixed contact 4, which is opposite to the movable contact 2, with a predetermined space (d) being set to such size that a surge that can be generated between the fixed contact 3 and the movable contact 2, when the movable contact 2 is separated from the fixed contact 3, can be discharged. A power unit A is connected between the movable contact 2 and the second fixed contact 4 and load equipment L is connected between the first fixed contact 3 and the second fixed contact 4 and then the movable contact 2 makes contact with the first fixed contact 3 to connect the power unit A to the load equipment L and when the movable contact 2 is separated from the fixed contact 3 a surge caused by lightning or the like is absorbed by the space (d) for shortcircuiting and the load equipment L can be protected from the surge even if the surge is superimposed between power lines at a high value.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electromagnetic relay.

[0002]

2. Description of the Related Art Conventionally, as a general method of using an electromagnetic relay, as shown in FIG. 2, a power supply device A and a load device L are connected in the middle of a power supply line in response to an electromagnet device (not shown). There is a type in which the contact part S that is separated is connected. This means that when the contact part S is closed, the load device L operates, and conversely, the contact part S
When is released, the load device L will not operate.

By the way, even when the contact portion S is in the open state, when a surge induced by lightning or a surge generated by another device connected to the same power supply unit A is superposed on the power supply line at a high value. , The contact part due to the surge
There is a risk of S being short-circuited and damaging the inside of load device L.

Therefore, from such a surge, the load device L
In order to protect the power supply, a surge absorber B such as an arrester is connected between the power supply lines on the power supply A side of the contact S. This surge absorber B is selected so as to short-circuit and absorb a high surge that may endanger the load equipment L.

[0005]

In the use of the above-mentioned conventional electromagnetic relay, even if a surge due to lightning or the like is superposed on the power supply line at a high value, the surge absorber is used.
Since B is connected, load device L
There is no danger of damaging the inside of the device, but it requires a separate element called the surge absorber B, which increases the number of assembly steps, space, and other factors, which increases costs.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electromagnetic relay capable of protecting a load device from a surge without providing another element.

[0007]

In order to solve the above problems, an electromagnetic relay according to the present invention includes an electromagnet device, a movable contact responsive to the electromagnet device, and a first fixed member in which the movable contact is closed and opened. A fixed contact, and a second fixed contact facing the movable contact with a predetermined gap when the movable contact is separated from the first fixed contact, the predetermined gap being It is configured such that a surge that may occur between the movable contact and the second fixed contact is set to a size that allows discharge.

[0008]

According to the electromagnetic relay of the present invention, the movable contact and the second
Power supply device between the first fixed contact and the second fixed contact.
When connecting a load device between the fixed contacts of
When the movable contact is closed to the first fixed contact, the power supply device and the load device are connected to operate the load device, and when the movable contact is separated from the first fixed contact, the load device does not operate. At the same time, since the movable contact faces the second fixed contact with a predetermined gap, surge due to lightning or the like is high between the power supply lines, that is, between the movable contact to which the power supply device is connected and the second fixed contact. Even if the values are overlapped with each other, by setting the above-mentioned predetermined air gap to a size that discharges a short circuit and absorbs a high surge that poses a danger to load equipment, another element called a surge absorber like the conventional example is set. Without providing, the load device can be protected from the surge by the electromagnetic relay itself that connects and disconnects the connection between the power supply device and the load device.

[0009]

An embodiment of the present invention will be described below with reference to FIG. This electromagnetic relay is a portion surrounded by a chain double-dashed line in the figure.

Reference numeral 1 denotes an electromagnet device, in which an L-shaped yoke 1c is fixed to an iron core 1b around which a coil 1a is wound, and an armature 1d is sucked and released to the iron core 1b.

A movable contact 2 is provided at one end of a conductive movable spring 2a fixed to the armature 1d and operates in response to the armature 1d. At the other end of the movable spring 2a, the armature 1d is an iron core.
It is fixed to the yoke 1c so that it also functions as a return spring for releasing from 1b, and is led out so that it can be connected to the outside. A position regulating portion 2b is provided at the tip of one end of the movable spring 2a so as to regulate the position of the movable contact 2 when the armature 1d is released from the iron core 1b.

Reference numeral 3 is a first fixed contact, and the armature 1d is an iron core 1b.
The movable contact (2) is provided so as to be closed and opened when it is sucked and released, and is guided so as to be connectable to the outside.

Reference numeral 4 is a second fixed contact, and movable contact 2 is the first.
When it is separated from the fixed contact 3 of the
Are provided so as to face each other with a predetermined gap d, and are led out so as to be connectable to the outside. Then, the predetermined gap d is set to a size capable of discharging a surge that may occur between the movable contact 2 and the second fixed contact 4.

As shown in FIG. 1, the electromagnetic relay includes a power supply unit between the movable contact 2 and the second fixed contact 4.
A can be used by connecting the load device L between the first fixed contact 3 and the second fixed contact 4, respectively.

Then, the movable contact 2 becomes the first fixed contact.
When closed to 3, power supply A and load device L are connected, load device L operates, and movable contact 2 is the first fixed contact.
When opened from 3, the load device L is disconnected from the power supply device A and does not operate, that is, the movable contact 2 and the first fixed contact 3 connect and disconnect the power supply device A and the load device L. Work.

At the same time, when the movable contact 2 is separated from the first fixed contact 3, the movable contact 2 has a predetermined gap d and faces the second fixed contact 4, so that it is between the power supply lines, that is, the power source. Moving contact 2 with device A and second fixed contact
4) Even if a surge due to lightning, etc. is superimposed at a high value, the specified air gap d should be set to a dimension that discharges a high surge that may pose a danger to the load equipment L and absorbs a short circuit. As a result, unlike the conventional example, the load device L can be protected from the surge by the electromagnetic relay itself without providing another element called the surge absorber.

In this embodiment, when the movable contact 2 is closed to the first fixed contact 3, the movable contact 2
The air gap between the second fixed contact 4 and the second fixed contact 4 becomes larger than the above-mentioned predetermined air gap d, and unless it is a surge of a correspondingly large value, it cannot discharge and short-circuit can be absorbed. In many cases, it is possible to absorb a short circuit in practice, and therefore, at this time as well, without using a separate element called a surge absorber as described above, this electromagnetic relay itself protects the load device L from a surge. The effect is that it can be done.

[0018]

The electromagnetic relay of the present invention includes a movable contact and a second contact.
Power supply device between the first fixed contact and the second fixed contact.
When connecting a load device between the fixed contacts of
When the movable contact is closed to the first fixed contact, the power supply device and the load device are connected to operate the load device, and when the movable contact is separated from the first fixed contact, the load device does not operate. At the same time, the movable contact faces the second fixed contact with a predetermined gap, so even if a surge due to lightning or the like is superimposed on the power supply line at a high value, the predetermined gap is dangerous to the load device. By setting a dimension that discharges a high surge that causes
The electromagnetic relay itself that connects and disconnects the power supply device and the load device can protect the load device from a surge.

[Brief description of drawings]

FIG. 1 is a configuration and circuit diagram showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a conventional example.

[Explanation of symbols]

 1 Electromagnet device 2 Moving contact 3 First fixed contact 4 Second fixed contact d Air gap

Claims (1)

[Claims] 1. An electromagnet device, a movable contact that responds to the electromagnet device, and a first fixed contact that closes and opens the movable contact.
A second fixed contact that faces the movable contact with a predetermined gap when the movable contact is separated from the first fixed contact, and the predetermined gap is the movable contact. An electromagnetic relay characterized in that a surge that may occur between the second fixed contact and the second fixed contact is set to a size that allows discharge.