JPS5819835A - Relay - 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 relay that can open and close a large load current with a small amount of electric power.

Conventional relays excite the coil by applying an input signal to the coil, operate the movable iron piece by this magnetic flux and close the contact, and demagnetize the coil by cutting off the input signal, causing the movable iron piece to return. The contact points are separated by force.

However, since the relays described above use a coil, which is a current-driven element, they consume a lot of power, making it difficult to obtain a highly sensitive relay, and when cutting off an AC load, the current phase at the time of cutting is constant. As a result, depending on the negative phase, the arc that occurs between the contacts may remain connected for as long as half a cycle, resulting in a lot of wear and tear on the contacts.

The present invention was made in view of these drawbacks, and its purpose is to be able to switch on and off a large load current with minimal power consumption, and to cut off an AC load at a phase near zero load current.
An object of the present invention is to provide a relay that prevents arcing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings showing embodiments thereof.

1 and 2 show a first embodiment of the relay according to the present invention, in which a fixed magnetic body 2 having a U-shaped longitudinal section is fixed on a base 11, and an insulating plate (31 is arranged in the center of the base). Two fixed contact pieces 4, . . . , 5-, which also serve as output terminals, are fixed on both sides of this insulating plate (31).

As shown in FIG. 3, the fixed contact pieces 4 and 5 are arranged to cross each other so as to pass through the fixed magnetic body 2, and a fixed contact 6 constituting a double break contact is provided at the tip of the fixed contact pieces 4 and 5.
, 7 are fixed. Incidentally, an AC power source and a load are connected in series to the output terminal portions of the fixed contact pieces 4 and 5.

The lower end of a movable magnetic piece 8 is swingably supported on an engaging protrusion 1a provided on the upper surface of the base 1.
can freely approach and separate from the end face of the fixed magnetic body 2, and when in contact, one closed magnetic path is formed.

The inner surface of the movable magnetic piece 8 has movable contacts 10 at both ends.
It has 11. The movable contact piece 9 is fixed, and when the movable magnetic piece 8 comes into contact with the fixed magnetic body 2, the contact is also closed at the same time.

One end of an actuation piece 12 made of an insulating and non-magnetic material is engaged with the tip of the movable magnetic piece 8.
The other end engages with the tip of a movable electrode 13 made of a thin aluminum plate and swingably supported by the support 1b of the base 1. This movable electrode 13 is always urged rightward in FIG. 1 by a return spring 14. An electret 16, which is an example of a voltage-driven element and has a fixed electrode 15 attached thereto, is installed on the base 1 so as to face the movable electrode 13. The fixed electrode 15 and the movable electrode 13 are connected to an input signal source 1 via input terminals 17 and 18, as shown in FIG.
9 is connected to the movable electrode 1 of the electret 16.
By positively polarizing the surface facing the movable electrode 3 and applying a negative signal to the movable electrode 13, the movable electrode 13 receives an electrostatic force in the direction of arrow P. Note that 20 is a discharge resistance.

Each of the above components is housed in a sealed container 21 made of glass or synthetic resin, and the sealed container 21 is filled with a vacuum or an arc-extinguishing atmosphere gas, such as 5F6 (sulfur hexafluoride).

The operation of the relay constructed as described above will now be explained with reference to FIG.

First, when an input signal is applied to the fixed electrode 15 and the movable electrode 13 at 10 o'clock, the movable electrode 13 is attracted to the electret 16 by electrostatic force, and the movable magnetic piece 8 is swung to the left in FIG. The contact closes as it moves and comes into contact with. As a result, a load current flows through the contacts, a magnetic flux Φ flows between the fixed magnetic body 2 and the movable magnetic piece 8, and the movable magnetic piece 8 is attracted to the fixed magnetic body 2. Therefore, the movable magnetic piece 8 is subjected to an operating force F1 caused by the movable electrode 13 and an attractive force F2 caused by the load current.

When the input signal is cut off at 13:00, when the load current value is relatively large, the electrostatic force between the movable electrode 13 and the electret 16 disappears, and the movable electrode 13 attempts to return to its original state due to the return spring 14 (but
Since the phase current value at [3 o'clock] of the load current is large, the movable magnetic piece 8 continues to be attracted to the fixed magnetic body 2. Then, as the load current value decreases over time and reaches a phase near zero (at 14 o'clock), the attractive force F2 due to one load current becomes smaller than the return force due to the return spring 14, and the movable magnetic piece 8 and the movable electrode 13 return to their original positions. , the contacts open. At this point, the load current value is almost zero, so almost no arc occurs when the load is cut off. When the contacts actually open, the moment of inertia of the movable magnetic piece 8 becomes even smaller.

In the present invention, magnetic flux is generated by the load current flowing through the contacts as described above, the load is cut off at a phase near zero load current, and the relay components are enclosed in a vacuum or a sealed container filled with arc-extinguishing atmospheric gas. This was done for the following reasons. That is, in order to open and close a large load current, the contact gap must be made large, but since the driving force of voltage driven elements is currently small, it is not possible to make a large contact gap. Therefore, by creating a vacuum inside the sealed container or filling it with arc-extinguishing atmosphere gas, the dielectric strength was increased and the contact gap was reduced, and the arc generated between the contacts was eliminated using the magnetic flux generated by the load current. .

As a result, it is possible to switch on and off a large load current with very little power consumption, and an ultra-high sensitivity relay can be obtained.

Note that if the inside of the sealed container 21 is evacuated, poor contact due to oxidation of the contact surface can be prevented.

In addition, when the contact has a double break mechanism as described above, the sum of the gaps between contacts 6 and 10 and between contacts 7 and 11 becomes the total contact gap, and the operating stroke of the contact can be shortened in proportion to the contact gap. , the power consumption of the voltage driven element can be further reduced. Furthermore, in the above embodiment, the two fixed contact pieces 4 and 5 are crossed and passed through the closed magnetic circuit in order to increase the magnetic flux caused by the load current, and functionally only one fixed contact piece is used. may be passed through a closed magnetic path, or may be passed multiple times.

6 and 7 show a second embodiment of the present invention, in which a bimorph 22 is used as the voltage driven element. In this case, when a signal is applied from the input signal source 19, the piezoelectric effect of the neuimorph 22 causes the bimorph 22 to curve in the direction of arrow P in FIG. 7, causing the movable magnetic piece 8 to swing via the actuation piece 12. This closes the contact and performs the same operation as in the first embodiment.

Note that in the present invention, the configurations of the movable magnetic piece 8, the fixed magnetic body 2, and the contact mechanism are not limited to those in the above embodiment; for example, as shown in FIG. 23 may be erected and a movable contact piece 24 may be attached to the back surface of the movable magnetic piece 8'.

The relay according to the present invention can be applied not only to switching AC loads as described above, but also to switching DC loads. In this case, a large contact pressure is obtained by the sum of the driving force of the voltage-driven element by the input signal and the attraction force by the load current, making it possible to further reduce the power consumption and size of the relay, and at the same time self-maintain. type relay can be obtained.

As is clear from the above explanation, according to the present invention, the fixed magnetic body and the movable magnetic piece are made to attract each other by the load current flowing through the contacts. It can be cut off at the phase of , and no arc occurs. Moreover, since the relay components are enclosed in a sealed container in an arc-extinguishing atmosphere, the dielectric strength is high and the contact gap can be made small. Therefore, it is possible to use a voltage driven element with a small driving force, and it is possible to open and close a large load current with low power consumption, and to obtain an ultra-high sensitivity relay.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a first embodiment of the relay according to the present invention, Fig. 2 is a plan view thereof, Fig. 3 is an exploded perspective view of the contact mechanism, and Fig. 4 is a diagram of the operating principle of the voltage drive element. , FIG. 5 is a time chart showing its operation, FIG. 6 is a longitudinal sectional view of the second embodiment, FIG. 7 is a diagram of the operating principle of the voltage drive element, and FIG. 8 is a partial perspective view of a modification. . 2...Fixed magnetic body, 4, 5...Fixed contact piece, 8...
- Movable magnetic piece, 9... Movable contact piece, 12... Actuation piece, 13... Movable electrode, 16... Electret, 1
9... Input signal source, 21... Sealed container, 22...
bimorph. Patent applicant: Tateishi Electric Co., Ltd. Agent
Patent Attorneys: Seihaku, Ao, and 2 others Figure 1, Figure 7, Figure 2, Figure 3, Figure 4, Figure 5, Ginya.

Claims (1)

[Claims] (1) A voltage-driven element driven by a minute electric power, a movable magnetic piece operated by the voltage-driven element, and a fixed piece that is arranged so as to be able to move toward and away from the movable magnetic piece, and forms a closed magnetic path when it comes into contact with the movable magnetic piece. A magnetic body, a contact mechanism that opens and closes in conjunction with the movable magnetic piece and is arranged so that the load current flowing through the contact when the contact is closed passes through the closed magnetic path, and each of the above components in an arc-extinguishing atmosphere. Relay 0 comprising a sealed container