JPH0131254B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an electromagnetic contactor that controls opening and closing of an input circuit of a motor or the like.

Conventionally, as this type of electromagnetic contactor, those shown in FIGS. 1 to 3 are known. Figure 1 is a partially cutaway plan view, Figure 1a is a plan view, Figure 1b is a partially cutaway plan view, and Figure 1c is a further partially cutaway plan view. be. FIG. 2 is a partially cutaway front view, FIG. 2a is a front view, and FIG. 2b is a partially cutaway front view. 3 is a partially cutaway side view, FIG. 3a is a side view, and FIG. 3b is a partially cutaway side view.

In the figure, 1 is a box-shaped insulating mounting base, 1a is a plurality of mounting holes provided in this mounting base 1,
Reference numeral 2 denotes an insulating base fixed to the mounting base 1 with tightening screws 3, and 4 is an E-shaped fixed core made of laminated silicon steel plates, which is attached to the mounting base 1 via a buffer spring 5. . Reference numeral 6 denotes an operating coil wound around the center leg of the E-shaped fixed core 4;
The upper surface is held in contact with the protrusion 2a of the base 2, respectively. 7 is this operating coil 6
and the coil terminal 8, 9 is a movable core disposed facing the fixed core 4 with a predetermined gap, and 10 is a lead wire between the movable core 9 and the pin 11.
The insulating crossbar 12 connected through the crossbar 12 is a trip spring that urges the crossbar 10 in the opposite direction to the mounting base 1, and is disposed between the crossbar 10 and the mounting base 1. . A movable contact 13 is disposed in a holding hole 10a provided in the cross bar 10, has a movable contact 14, and is pressurized by a contact spring 16 held by a spring support 15. A fixed contact 17 is made of an elastic material and has a fixed contact 18 facing the movable contact 14. It has a terminal screw 19 for connecting the main circuit wire, and is fixed to the base 2 by its elastic force. This movable contact 14 and fixed contact 1
The gap between the movable iron core 9 and the fixed iron core 4 is smaller than the gap between the movable iron core 9 and the fixed iron core 4. Reference numeral 20 denotes a magnetic metal arc runner provided for arc extinguishing, and is fixed to the base 2 by its elastic force. 21 is a shaded coil.

The operation will be explained based on the above configuration.

When an AC drive voltage is applied to the operating coil 6, a magnetic flux is generated from the operating coil 6, and an electromagnetic attraction force is generated between the fixed core 4 and the movable core 9, causing the movable core 9 to resist the tripping spring 12. It is attracted to the fixed iron core 4. At the same time, the cross bar 10 connected to the movable iron core 9 moves toward the fixed iron core 4 side, and this cross bar 1
The movable contact 14 of the movable contact 13 held at zero comes into contact with the fixed contact 18 of the individual contact 17 . At this time, the gap between the movable core 9 and the fixed core 4 is made larger than the gap between the movable contact 14 and the fixed contact 18, so when the movable core 9 is attracted to the fixed core 4, the crossbar 10 is movable. It moves further toward the fixed core 4 than the contact position between the contact 14 and the fixed contact 18. Therefore, the contact spring 16 is compressed and deformed, and this spring pressure is transmitted to the movable contact 13.
The movable contact 14 and the fixed contact 18 can come into contact with each other with a predetermined contact pressure.

When the drive voltage applied to the operating coil 6 is removed, the electromagnetic attractive force between the fixed core 4 and the movable core 9 disappears, and the crossbar 10 is moved to the mounting base 1 by the biasing force of the compressed tripping spring 12. Moving in the opposite direction, the movable contact 14 that was in contact with the fixed contact 18 separates from this fixed contact 18. At this time,
The arc generated between the movable contact 14 and the fixed contact 18 is extended onto the arc runner 20, cooled, divided, and extinguished.

Furthermore, since the operating coil 6 is driven by alternating current, the core vibrates due to its alternating magnetic flux, and in order to prevent this vibration, a shade removal coil 21 is installed to smooth out the pulsating attraction force caused by the alternating magnetic flux.

However, there is a limit to the effectiveness of the shade removal coil 21. For example, if rust occurs on the contact surface between the fixed core 4 and the movable contact 9, the smoothing effect will be reduced and the core will vibrate, causing noise to the outside. It had the disadvantage of emitting . Further, in order to prevent this noise, periodically removing rust from the iron core or attaching a soundproof cover or the like poses a problem because the handling or assembly work becomes complicated.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional technology.In addition to providing a rectifier circuit that converts the driving voltage of the operating coil into direct current, the applied voltage of the operating coil is The purpose of this invention is to provide an electromagnetic contactor that is noiseless and has good handling and assembly workability by suppressing the noise and mounting these control parts on a single printed circuit board.

Hereinafter, one embodiment of the present invention will be described based on the drawings. Note that the same or equivalent parts as in the prior art are given the same reference numerals and detailed explanations are omitted.

Figure 4 is a partially cutaway plan view, Figure 4a is a plan view, Figure 4b is a partially cutaway plan view, Figure 4c is a partially cutaway plan view.
2 is a plan view showing another part cut away. FIG. 5 is a partially cutaway front view, FIG. 5a is a partially cutaway front view, and FIG. 5b is another partially cutaway front view. In addition, Fig. 6 is a partially cutaway side view.
Figure a is a side view, and Figure 6b is a partially cut side view.

In the figure, 22 is an arc cover made of heat-resistant insulating material provided for arc extinguishing, and 23 and 24 are grids of magnetic metal plates installed inside this arc cover 22, which are arranged at each contact point where an arc occurs. It has been set up. 25 is a coil terminal plate made of a conductive thin plate connected to the operating coil 6; 26 is a printed circuit board;
7 is a mold casting agent for fixing this printed circuit board 26 to the mounting base 1; 28 is a lid member for closing an opening 1b provided on the side of the mounting base 1; be. 29 is a buffer rubber 3 provided between the mounting base 1 and the fixed core 4.
0 is a leaf spring that connects the movable iron core 9 and the crossbar 10.

FIG. 7 is a control circuit diagram of the operating coil 6. In the figure, 31 is a changeover switch that is closed when the power is turned on and is opened after the fixed core 4 attracts the movable core 9. 32 is the changeover switch 31 and This is a voltage drop circuit connected in parallel, and is constructed by connecting a resistor R and a capacitor C in series. 33 is a rectifier circuit that converts AC power into DC to drive the operating coil 6;
Together with the voltage drop circuit 32, it constitutes an operating coil control section. This rectifier circuit 33 is constituted by a bridge circuit of diodes D. VAR is a barista.

The above-mentioned changeover switch 31 has a push button part 31a, as shown in FIG. It is configured to be in the open state immediately before the opening. This changeover switch 3
1. The operating coil 6 and each control component shown in FIG. 7 are mounted on a single printed circuit board 26.

FIG. 8 is a perspective view of the operating coil 6, changeover switch 31, and various control parts mounted on the printed circuit board 26. In the figure, 25a is the coil terminal plate 2.
The pin part formed at the bottom of 5 connects the printed circuit board 2.
6 is soldered. Reference numeral 25b denotes a terminal portion formed at the upper part, and has a hole for screwing the coil terminal 8.

FIG. 9 is a perspective view of the operating coil 6 seen from the back side. In the figure, 6a is the winding start end of the coil, 6b
34 is the winding end, 34 is a coil spool, 35 is two coil leads arranged on this coil spool 34, and each has two pin parts 35a, 35a,
35b, 35b. pin part 35a,
35a, the winding start end 6a or the winding end 6b of the coil is wound, and the other pin portions 35b, 35
b is configured to be soldered to the printed circuit board 26.

FIG. 10 is a perspective view of the changeover switch 31. In the figure, 31b is a pin-shaped terminal connected to the printed circuit board 26 by soldering. This changeover switch 3
1 is fixed to the mounting base 1 via a printed circuit board 26 with tightening screws 36, as shown in FIG. 6, in order to ensure accurate switching positions of the contacts.

FIG. 11 shows a fixed core support member 37, and this fixed core support member 37 is made of a material having a small Young's modulus.
For example, the pawl portion 37a is made of thermoplastic resin or the like.
is provided. It is fixed to the base 2 by this claw portion 37a, and a lower end surface 37b that comes into contact with the fixed iron core 4 is formed into a curved surface.

FIG. 12 shows a tripping spring receiver 38, and this tripping spring receiver 38 is provided with a protrusion 38a.
Dovetail groove 1c provided with this protrusion 38a on mounting base 1
It is fitted and fixed. A trip spring 12 is compressed and disposed between the trip spring receiver 38 and the cross bar 10.

In addition, the fixed core 4 is, as shown in FIG. 13,
It has a trapezoidal cross-sectional shape, and a non-magnetic spacer 39 made of a thin non-magnetic metal plate is bonded to the surface that contacts the movable iron core 9 in order to prevent a delay in falling of the iron core.

As described above, in this electromagnetic contactor, the operating coil control section, the changeover switch 31, and the operating coil 6 are mounted on a single printed circuit board 26, and are formed into an integral structure using a mold casting material 27. Also,
Since the lower end surface 37b of the fixed core support member 37 that comes into contact with the fixed core 4 is formed with a curved surface as shown in FIG. 11, the fixed core 4 can be rotated in the direction of the arrow A shown in FIG. It is possible to make close contact with the contact surface of the U-shaped movable core 9 without any gaps, thereby stabilizing the suction force characteristics in the core adsorption state.

When inputting AC drive voltage to this electromagnetic contactor,
Since the changeover switch 31 shown in FIG. 7 is in the closed state, the voltage applied to the operating coil 6 becomes direct current that has been full-wave rectified by the rectifier circuit 31. Then, when the fixed iron core 4 attracts the movable iron core 9, the changeover switch 31 becomes open, and the rectifier circuit 31 performs full-wave rectification of the voltage via the capacitor C and the resistor R, so that the operating coil 6 has a voltage drop. Direct current is applied to maintain the adsorption state of the iron core. This is because the electromagnetic energy in the adsorbed state of the iron core may be smaller than the electromagnetic energy in the middle of suction, and by operating this changeover switch 31, power consumption is reduced and the temperature rise of each part is also reduced. Therefore, the lifespan of the equipment can be improved. Further, since the voltage applied to the operating coil 6 is a direct current, there is no pulsation of the attraction force of the iron core, and therefore there is no vibration and no noise is generated.

If the drive voltage is different, the electronic components such as the voltage drop circuit 30 and rectifier circuit 31 shown in FIG. Since it is fixed to the mounting base 1 with the mold casting agent 27, there is no possibility of making a mistake in the combination of the electronic component and the operating coil 6 during modification due to the change. Furthermore, the modification work is as simple as replacing the mounting base 1.

As described above, according to the present invention, a rectifier circuit is provided that replaces the AC power source with DC power to drive the operating coil, and is in the closed state when the power is turned on, and in the open state after the fixed iron core attracts the movable iron core. Connecting a changeover switch between the rectifier circuit and the AC power source,
A voltage drop circuit that suppresses the voltage applied to the operating coil is connected in parallel with this changeover switch, and an operation coil control section constituted by this voltage drop circuit and the rectifier circuit, the operation coil, and the changeover switch. mounted on a single printed circuit board,
This has the effect of providing an electromagnetic contactor that is noiseless and has good handling and assembly workability.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway plan view of a conventional electromagnetic contactor, Fig. 1a is a plan view, Fig. 1b is a partially cutaway plan view, and Fig. 1c is a partially cutaway plan view. It is a cut plan view. FIG. 2 is a partially cutaway front view of a conventional electromagnetic contactor, FIG. 2a is a front view, and FIG. 2b is a partially cutaway front view. FIG. 3 is a partially cutaway side view of a conventional electromagnetic contactor, FIG. 3a is a side view, and FIG. 3b is a partially cutaway side view. FIG. 4 is a partially cutaway plan view of one embodiment of the present invention, FIG. 4a is a plan view, FIG. 4b is a partially cutaway plan view, and FIG. FIG. FIG. 5 is a partially cutaway front view of one embodiment of the present invention; FIG. 5a is a partially cutaway front view;
FIG. 5b is a front view of another part cut away. FIG. 6 is a partially cutaway side view according to the present invention.
FIG. 6a is a side view, and FIG. 6b is a partially cut away side view. Figure 7 is a control circuit diagram of the operating coil.
Figure 8 is a perspective view of the operating coil, changeover switch, and various control parts mounted on the printed circuit board, Figure 9 is a perspective view of the operation coil seen from the back, Figure 10 is a perspective view of the changeover switch, and Figure 11 is FIG. 12 is a perspective view of the fixed core support member, FIG. 12 is a perspective view of the tripping spring receiver, and FIG. 13 is a perspective view of the fixed core. 1...Mounting base, 1b...Opening, 4...Fixed core, 6...Operation coil, 9...Movable core, 26...
...Printed circuit board, 27...Mold casting agent, 31
...Selector switch, 32...Voltage drop circuit, 33
... Rectifier circuit. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. In an electromagnetic contactor in which a fixed core, a movable core, and an operating coil are mounted on a mounting base, and the operating coil is driven by AC power, the AC power is converted to DC to drive the operating coil. A switching circuit is provided between the rectifier circuit and the AC power supply, and a switching switch is connected between the rectifying circuit and the AC power supply, and the switch is closed when the power is turned on and is opened after the fixed core attracts the movable core. A voltage drop circuit that suppresses the voltage applied to the operation coil is connected, and an operation coil control section constituted by the voltage drop circuit and the rectifier circuit, the operation coil, and the changeover switch are connected to a single printed circuit board. An electromagnetic contactor characterized by being installed in a. 2. The electromagnetic contactor according to claim 1, wherein the printed circuit board on which the operating coil control section, the operating coil, and the changeover switch are mounted is mounted on a mounting base to form an integrated structure. 3. The electromagnetic contactor according to claim 2, wherein the fixed core is inserted through an opening provided on the side surface of the mounting base. 4. The electromagnetic contactor according to claim 2, wherein the printed circuit board is fixed to the mounting base by mold casting to form an integral structure.