JPS59160929A - Self-holding type electromagnetic contactor - 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 improvements in self-holding electromagnetic contactors.

In a conventional electromagnetic contactor, when opening and closing an electric circuit, the contactor is opened and closed by the suction force of an AC electromagnet and the return force of an elastic element such as a spring, but when the electric circuit is closed. , that is, the contactor made contact! To maintain this state, alternating current must be applied to the electromagnet. This constant AC current not only consumes electricity, but also has drawbacks such as failures due to damage to the electromagnetic coil due to temperature rise.

As a solution to the above drawbacks, there is a self-holding magnetic contactor that uses a permanent magnet instead of an electromagnet.Since this device requires no electricity other than an instantaneous direct current, it is energy-saving and increases the temperature. Although this has the advantage of eliminating damage to the excitation coil and the occurrence of beats caused by the noise, it also has problems such as the need for a rectifier circuit and a switch for changing the polarity of the power source because the drive power source is direct current.

In order to solve these problems, the present inventor developed a self-holding electromagnetic contactor that uses a permanent magnet and can be driven by alternating current (Japanese Patent Application No. 57-1495)
55).

This self-holding electromagnetic contactor can be used with alternating current, so there is no need for a rectifier circuit, a power supply polarity change switch, etc.
Therefore, it has both the advantages of a conventional electromagnetic contactor that uses only electromagnets and the advantages of a self-holding contactor that uses permanent magnets (ν), but it is better to use a high coercive force as the permanent magnet in the magnetic circuit. State of being magnetized in a certain direction (1
Since the plunger is used in a state of saturation magnetization) and the plunger is attracted and released, it is conventionally used as shown in the circuit in Figure 1 to prevent vibrations caused by alternating current during attraction and release. Similar to electric and magnetic contactors, there are an A contact, a contact that changes from an open circuit to a closed circuit when the coil is energized, and a B contact, a transition point that changes from a closed circuit to an open circuit when the coil is energized, and these are connected to the plunger. When these contacts are opened, discharge occurs at the contact 11A1 and a spark is generated.

The contact 16 is composed of a contact a which changes from a closed circuit to an open circuit by the excitation of the excitation coil 7, and a contact σ which changes from a closed circuit to an open circuit by the excitation of the single coil 8. Although the spark generated during this discharge is almost negligible, the discharge is large when the contact of the input terminal 11; Puko.

The present invention is an improved invention made in an attempt to solve this problem without increasing the number of parts, and includes a magnetic circuit in which an excitation coil and a permanent magnet are arranged in series, and a movable part of the magnetic circuit is connected δ. h[Equipped with 1 contactor for opening and closing electric and air circuits including a shank that springs in the opening direction, and a fixed contactor'fc installed opposite thereto, t? Applying an alternating current of a magnetomotive force to the excitation coil /L/ that changes the permanent magnet from an almost unmagnetized state to almost completely magnetizing it, and applying an alternating current of a magnetomotive force that is almost lower than the magnetomotive force. The gist of this paper is a self-holding electromagnetic contactor that opens and closes an electric circuit.

In this case, the excitation coil and the permanent magnet are arranged in series, for example, as shown in FIG. This means that they are arranged so that they are in the same direction. Further, it is preferable that the permanent magnet used in the present invention has a low coercive force, such as an alnico cast magnet, rather than a permanent magnet having a high coercive force, such as a Fehuite rare earth magnet.

Hereinafter, the present invention will be explained with reference to the drawings listed as the undercurrent side.IQI
do.

Figure 2 shows the self-protection of the present invention. FIG. 3 is a schematic diagram showing an example of the contactor machine J1.

Inside the outer frame 1, a frame yoke 2 containing an excitation coil/l/8 ligature is housed. Non-magnetic to medium heat of frame yoke 2:
The bottom of the non-magnetic tube 5 is in contact with the frame yoke 2, and houses a permanent magnet 6 with one side of the width sandwiched between fixed cores 494, and the permanent magnets 6 are arranged in series. Arranged magnetic circuit 7f: configured. The direction of magnetization is shown by the broken line in FIG.

Above the permanent magnet 6, a plunger 3 that can slide up and down along a non-magnetic tube 5 is inserted, and a +bJ moving contact 1 is attached to the upper end of a non-magnetic support member 9 fixed to the top of the plunger 3.
A fixed contact 14 is provided on the outer frame 1 facing the movable contact 13, and a nubling 1 is provided as a resilient element that acts in the direction between the plunger 3 and the permanent magnet 6 (L).
0 to both arms 11 of the support member 9 and the outer frame 1 f14. It is set up on i.

In this case, if the permanent magnet 6 is in an unmagnetized state, the 31st magnet 6
When the switch is closed, an alternating current (rl-i) is applied to the excitation coil 8, and an attraction similar to that of a conventional electromagnet occurs. The movable contact 13 and fixed contact 14 of the circuit are closed, but the permanent magnet 6 is magnetized σ at the same time as the above-mentioned attraction action. However, in this case, the direction of magnetization (polarity) of the permanent magnet 6 is the same as the excitation direction of the excitation coil 8, so even in the closed state of 1-, the flap 3 does not vibrate. In the contactor of the present invention, as shown in the electrical circuit of Fig. 3, it is possible to eliminate the contact point which is rarely needed in the circuit of Fig. Even if the switch is opened, the permanent magnet 6 is self-retained by the magnetic force in the direction in which the switch was magnetized at the moment of opening, and the electrical circuit contacts 1B and 14 are closed 8.
I got it! (Maintain the state of.

When the electric circuit contacts 13 and 14' are closed, an instantaneous alternating current is applied to the excitation coil 8 and the electric current is applied to the contact a. It will be released.

In the illustrated example, a resistor R is inserted between the exciting coil and the contact point a in order to perform both attracting and releasing operations with one exciting coil 8. If the resistor R is not inserted, it is the same as the magnetization performed at the time of adsorption, and the releasable region (4) 1. li is difficult to occur because it is only for a moment near the coercive force Hc. Resistance R
By inserting the magnetomotive force of the excitation coil 8, the magnetomotive force of the excitation coil 8 is made to be lower than the magnetomotive force at the time of attraction, and the maximum magnetomotive force is made to be below the vicinity of the coercive force Hc, so that release (ζ is carried out with certainty). Of course, instead of using this resistor R, a release coil having the maximum magnetomotive force as described above may be provided separately.

As described above, when a releasing alternating current is applied to the excitation coil 8, the alternating current half cycle tr:i in the same direction as the magnetic flux emitted by the permanent magnet 6 moves to the first quadrant 7 of the operating point of the permanent magnet 6.
Although it is not effective for releasing l/rC, the remaining half cycle is in the direction of canceling out the magnetic flux sent to the attraction part of the permanent magnet 6, so the attraction force by the permanent magnet 6 is reduced, and this attraction force becomes the elastic element. When the elastic force becomes less than 10, an air gap is created and the magnet operating point is aligned in the direction of lowering, which is then accelerated and released, and the contacts 13 and 14 of the electric circuit are opened.

The generation of sparks at contact a during this release is comparable to that of conventional electromagnetic contactors. Permanent magnet 6ge 11 after release
In the desulfurized state, of course, there is no suction force to self-hold against the elastic element IO, and the next suction is performed by exciting the permanent magnet 6 from a substantially unmagnetized state.

As an example, a Fe-Cr-Co magnet with a good squareness and a coercive force of about 6000e is used as the permanent magnet 6, and the maximum magnetomotive force of the excitation coil 8 during attraction is equal to the coercive force of the permanent magnet at a power supply voltage of 220μ. It was set to be more than three times as large. In addition, the voltage of the AC voltage for release was lowered to 120V by the resistor R, but
A guaranteed release was made. The AC used was a commercial 60 cycles.

According to the above-mentioned invention, the structure is not complicated compared to the electromagnetic contactor currently used.
It is possible to obtain a self-holding electromagnetic contactor that is energy-saving and free from discharge failure, and has great industrial value.

[Brief explanation of drawings]

FIG. 1 is an operational electrical circuit diagram of the AC self-holding electromagnetic contactor according to the above invention. FIG. 2 is a schematic diagram showing the lid of an example of the AC self-holding electromagnetic contactor according to the present invention. Figure 3 (
ζ FIG. 2 is an operational electrical circuit diagram of the electromagnetic contact remover. 3:]” Lansher, 4: Identification core, 6: Permanent magnet, 7
: Resistance, 8: Excitation Koinope lo: Elastic element (Nuf" link), 13: Weightable': Contact a, 14: Fixed contact, 1
5: Power supply, Iiroro': Open/close switch, 16: [Point -1
ζ Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] (1) Excitation coil and permanent value: A magnetic circuit in which stones are arranged in series, a movable contact for opening and closing an electric circuit including an element that is connected to a movable part of the magnetic circuit and springs in the direction of separation, and a corresponding the magnetomotive force is lower than the magnetomotive force, and an alternating current of a magnetomotive force is applied to the excitation coil to substantially completely magnetize the permanent magnet from a substantially unmagnetized state; 1. A self-holding type electromagnetic contactor characterized in that the stain circuit is closed by applying 15tj.