JPH0131650B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic switching device, and particularly to an electromagnet drive device thereof.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a front partial sectional view of an embodiment of the present invention, and FIG. 2 shows a half sectional side view of the same.

In FIGS. 1 and 2, reference numeral 1 indicates an arc extinguishing arc box made of a heat-resistant material, in which a grid 2 and a commutator plate 3 made of magnetic metal are arranged in accordance with the number of phases of the electrical circuit to be opened and closed. The setting is fixed. 4
is a cross bar, 5 is a movable contact, 6 is a movable contact attached to both ends of the movable contact 5, 7 is a movable contact presser, 8 is a presser spring support, 9 is a contact spring, 1
0 is a stopper. The contact spring 9 is compressed and fixed between the lower part of the stopper 10 and the lower end of the presser spring support 8, and the upper end of the presser spring support 8, the upper surface of the movable contact presser 7, and the movable contact 5.
The upper surface and the lower surface of the movable contact holder 7 are assembled in contact with each other. Further, the stopper 10 is inserted into the stopper hole 4a of the cross bar 4. 1
Reference numeral 1 designates a base, which has an open bottom as shown in the exploded perspective view of FIG. 3, and further has an opening 11a for drawing out an electromagnetic drive device, which will be described later, on the side surface. 12 is a terminal fixed to the upper part of the base 11 with a screw, 13 is a U-shaped fixed contact screwed to the upper surface of the terminal 12, and a fixed contact 14 is attached to the upper surface. 15 is an arc runner fixed to the fixed contact 13; 16 is an insulating barrier, which serves to electrically insulate the terminals 12; and a groove (not shown) provided in the arc box 1 and the base 11. A part of it is inserted into and fixed between the two. 17 is a movable buffer rubber;
A movable core 18 is connected and fixed to the lower part of the cross bar 4 by a movable core pin 22. Reference numeral 19 indicates a fixed iron core, which is arranged to face the movable iron core 18 with a predetermined gap therebetween. 20 indicates an electromagnetic drive control device (hereinafter referred to as drive control device),
It is arranged so that it is inserted through the fixed iron core 19, and a magnetic flux generating device 2 such as an electromagnetic coil is installed inside it.
1 is included. Also, the drive control device 2 in FIG.
As shown in the perspective view of 0 viewed from below, a rail engagement piece 20b for forming a U-shaped recess 20a is provided. Note that 20c is a through hole into which the fixed iron core 19 is inserted. Further, reference numeral 22 denotes a fixed buffer spring, which is attached to the lower part of the fixed iron core 19 and mainly functions to reduce the impact on the mounting board surface (not shown) when the electromagnetic contactor is inserted. Reference numeral 24 designates a fixed core pin, as shown in FIGS. 2 and 3, which is provided to penetrate the lower part of the fixed core 19, and both ends thereof protrude from the fixed core 19. A fixed buffer rubber 25 is fitted through each end of the fixed iron core pin 24, and a guide 26 is further fitted to cover the fixed buffer rubber 25. The guide 26 is made of a material with low frictional resistance, and has a guide recess 26a approximately equal to the outer diameter of the fixed buffer rubber 25. Reference numeral 27 indicates a rail plate, and two U-shaped rails 27a which are parallel to each other are formed in the central portion of the rail plate. Further, a rail stopper portion 27b is formed at the rear end of the rail. The rail plate 27 is connected to the base 11.
It is fastened and fixed by a tightening screw 28. The drive control device 20 also incorporates a ratchet 29 shown in FIGS. 1 and 4. Ratchet 2
9 is held by the longitudinal convex portion 20d of the drive control device 20 so as to be able to move vertically in the ratchet recess 29a, and is further urged downward by a return spring 30.
An engaging protrusion 29b is formed at the lower part of the ratchet 29, and is configured to engage with an engaging hole 27c provided in the rail plate 27. 31
indicates a tripping spring, which is disposed between the lower end of the cross bar 4 and the upper surface of the rail plate 27 and always urges the cross bar 4 upward. A mounting plate 32 has mounting holes for mounting the electromagnetic contactor on a mounting board surface (not shown), and is fixed to the lower side of the rail plate 27 with screws. Reference numeral 33 indicates an auxiliary contact portion, which is fixed to the side surface of the base 11. The arc box 1 is fixed to the base 11 by screws, and the cross bar 4 is held and guided by the inner wall of the base 11 so as to be vertically movable.

The electromagnetic switching device according to the present invention is constructed as described above, and its operation will be explained next.

1 and 2, when a drive voltage is applied to the drive control device 20, the magnetic flux generated by the drive control device 20 causes the movable iron core 18 and the fixed iron core 19 to
During this time, an electromagnetic attraction force is generated, and the cross bar 4 connected to the movable iron core 18 moves downward against the tripping spring 31, and the movable contact 6 and the fixed contact 14 come into contact with each other. Since the core gap between the movable core 18 and the fixed core 19 is larger than the contact gap between the movable contact 6 and the fixed contact 14,
The cross bar 4 is moved further below the contact contact position to close the iron core. Therefore, the contact spring 9 is compressed and deformed, and this spring pressure is transmitted to the movable contact 5 via the press spring support 8 and the movable contact presser 7, and connects the same electrical circuit with the terminal 12 with a predetermined contact pressure. Electrical continuity is established between the opposite terminals 12 to be formed.

When the drive voltage applied to the drive control device 20 is removed, the electromagnetic attractive force between the movable core 18 and the fixed core 19 is eliminated, and the crossbar 4 moves upward due to the biasing force of the compressed tripping spring 31. This causes the contacts to open. At this time, an arc is generated between the movable contact 6 and the fixed contact 14, but this arc is transferred from the movable contact 6 to the commutator plate 3, and from the fixed contact 14 to the arc runner 15, respectively.
Furthermore, it is drawn into the grid 2 by electromagnetic repulsion caused by the arc current and the contact current, and is cooled, separated, and extinguished. As described above, by opening and closing the drive voltage of the drive control device 20, the electric circuit connected between the terminals 12 and 12 is opened and closed.

The drive control device 20 will be explained in detail with reference to FIG. 5. 50 generates magnetic flux and the movable iron core 1
8 is attracted to and held by the fixed iron core 19; 51 is electrically connected to the operating coil 50; a control circuit section for controlling the magnetic flux generated from the operating coil 50; 52, controlling the alternating current voltage from the power supply; Coil terminal for applying voltage to the circuit section 51; 53 is a changeover switch section for switching the control circuit in order to change the current flowing through the operating coil 50 during attraction and steady state; 54 is the operating coil 50, the control circuit section 51, and the coil terminal 5;
2. Store the changeover switch part 53 and install the rail plate 27
55 is a coil cover that covers the upper surface of the coil case 54 for insulation and dustproofing; 56 is a ratchet portion that prevents the coil case 54 from coming off after it is inserted into the rail plate 27; and 57 is an operating coil. 50 is a casting mold in which the control circuit section 51 and the changeover switch section 53 are housed in a coil case 54 and then fixed therein.

Then, the sixth drive control device 20 is expanded.
As shown in FIG. 7, the control circuit section 51 consists of a printed circuit board 58 and a circuit element 59,
0, the coil terminal 52, the changeover switch part 53,
It is electrically connected to the operating coil 50. The changeover switch section 53 includes a push rod 61 operated by the movable iron core 18 or the crossbar 4, a switch return spring 62 that returns the push rod 61 to its original position, and a snap action depending on the position of the push rod 61. It consists of a movable switch contact 63, a fixed switch contact 64 opposite to the movable switch contact 63, a switch cover 65 for housing these, and a switch base 66. The lead wire 60A coming out from the changeover switch section 53 passes through the notch groove 54A of the coil case 54 and connects to the printed circuit board 5 of the control circuit section 51.
8 is connected by soldering. Above coil terminal 5
2 is press-fitted into the coil case 54, and the lead wire 60B coming out from the coil terminal 52 passes through the notch groove 54A of the coil case 54 and connects to the control circuit section 5.
It is connected to the printed circuit board 58 of No. 1 by soldering.

Further, the casting mold 57 has a printed circuit board 58.
It is located up to the top surface of the printed circuit board 58 and serves as an insulator between patterns on the printed circuit board 58 and between the ground. It efficiently radiates heat generated from the operating coil 50 and circuit components to the outside, and also serves as a moisture barrier. The coil cover 55 has a hook portion 55X that fits into the protrusion 54X of the coil case 54.
and is fixed to the coil case 54,
When the casting mold 57 hardens after casting by the embedding protrusion 55Y fixed by casting, it is fixed so that it will not come out from the casting mold 57. The coil cover 55 covers the control circuit section 51 and the operating coil 5.
0, and serves as electrical insulation when the casting mold 57 alone is incomplete.

Further, the electric circuit diagram of the drive control device 20 is shown in the eighth
As shown in the figure. In FIG. 8, R is a resistor, C is a non-polar capacitor, B is a varistor, D is a diode, and Rc is an internal resistance of the operating coil 50. These circuit components are soldered to a U-shaped printed circuit board 58 shown in FIG. 6 to form an electric circuit.

Next, the operation of the drive control device 20 will be explained.
When the operating power is applied to the coil terminal 52, the selector switch 53 is in the ON state in the open state, both ends of the resistor R and the capacitor C are short-circuited, and the operating power voltage is connected to the operating coil 50 through a diode. A total voltage full-wave rectified by D is applied,
A large current flows, determined only by the internal resistance Rc. This allows a large suction force to be obtained at the time of injection. Due to this suction force, the movable core 18 begins to move in the direction of the fixed core 19, and just before the two cores attract each other, the push rod 61 turns the switch section 53 OFF.
become a state. The arc generated at the changeover switch section 53 during this switching is attracted to the circuit of the capacitor C and the resistor R, and damage to the contacts of the changeover switch section 53 is minor. When the changeover switch section 53 is turned OFF, the voltage drop due to the capacitor C connected to the AC side acts greatly, and the current flowing through the operating coil 50 is almost determined by the capacitor C, which is a small full-wave rectified current. Become.

In steady state, there is almost no leakage of magnetic flux, so
In addition, since the magnetic resistance due to the air gap is small, it can be held even with a small current. Since the timing is set in the changeover switch section 53 so that the timing of switching from the large suction force at the time of closing to the small suction force during steady state is just before the iron core is attracted, the operation at the time of closing becomes stable.

When the application of the operating power to the coil terminal 52 is stopped, the attractive force disappears, and the movable core 18 becomes the fixed core 19.
become further apart. Then, after the movable contact 6 and the fixed contact 14 are separated by the push rod 61 that follows the movable iron core 18, the changeover switch portion 53 is switched to the ON state. At this time, the charge stored in the capacitor C flows through the resistor R to the switch movable contact 63 and the switch fixed contact 64, and the contact surfaces are cleaned. Further, the voltage induced by the operating coil 50 is absorbed by the flywheel circuit of the diode D, and no surge is released to the outside.

After the main contact is separated, the changeover switch section 53
Since it switches from OFF to ON, even if some voltage remains between the coil terminals 52, the attraction force that attracts the movable iron core 18 at that position is small, and it stably settles into the open state without having to turn it on again. .

The fixed iron core 19 has a U-shape, one leg of which passes through the operating coil 50, and a control circuit section 51 is arranged around the other leg. In order to shorten the time, a step 67 is provided on the armature surface. Furthermore, the movable core 18 is I-shaped, and a spacer 68 made of a non-magnetic material is provided on the polarized surface of the movable core 18 to prevent attraction due to residual magnetism.
Since the magnetic flux flowing inside the iron core is DC magnetic flux, it is constructed from laminated steel of structural steel plates.

Further, in the changeover switch section 53, when the electromagnetic contactor is open, the switch movable contact 63 and the switch fixed contact 64 are in contact, and when the fixed core 19 is excited and the movable core 18 is attracted to the fixed core 19. After the push rod 61 is pushed by the movable core 18 and the movable contact 6 and the fixed contact 14 come into contact, the switch movable contact 63 is fixed by the snap action just before the movable core 18 and the fixed core 19 collide. The contact 64 is opened. When the excitation is released, the movable core 18 begins to move away from the fixed core 19, and the push rod 61 releases the switch return spring 62.
The movable core 18 is followed by the movable iron core 18. This push rod 61
After the movable contact 6 and the fixed contact 14 are separated by the movement, the switch movable contact 63 and the switch fixed contact 64 are brought into contact by the snap action. In order to perform such a switching operation with temporal hysteresis when closing and opening, the push rod 61 has a lever shape at the top and bottom, sandwiching the switch movable contact 63.

As explained above, according to this inventive device,
Since a notch groove is formed in the coil case,
Wiring inside the case can be done easily and without requiring wiring space. In addition, since the coil cover is fixed by fitting the hook part of the coil cover to the protrusion of the coil case, the coil cover does not lift up during molding, making it easy to mold. . Furthermore, the operating coil and the control device that controls the energization of the operating coil can be efficiently and compactly arranged near the iron core that generates the magnetic flux, and the electromagnet drive device can be arranged as an integrated component inside the product.
Therefore, the handling of the electromagnet drive device is greatly improved, and the product itself can be made much smaller.
For example, even if the specifications of the customer's operating power supply change,
This has the advantage that the entire device can be easily replaced.

Integration improves the reliability of the device against external factors, and if mold casting is used as a fixing method inside the coil case, heat dissipation is improved, thermal improvement is achieved, and the surrounding environment is improved. It is almost unaffected by the atmosphere, and the internal elements are protected against vibration and shock, making it highly reliable.

[Brief explanation of drawings]

The drawings all show an embodiment of the present invention; FIG. 1 is a front partial cross-sectional view, FIG. 2 is a half-sectional side view of the device shown in FIG. 1, and FIG. 3 is a drive for operating the movable iron core. FIG. 4 is a perspective view of the drive control device seen from below; FIG. 5 is a perspective view of the drive control device seen from above; FIG. 6 is an exploded perspective view of the drive control device shown in FIG. 5. FIG. 7 is an exploded perspective view of the changeover switch section, and FIG. 8 is an electric circuit diagram. In the figure, 18 is a movable core, 19 is a fixed core, 20 is a drive control device, 50 is an operating coil, 5
4 is a coil case, 57 is a casting mold, 20c
is a through hole, C is a capacitor, and D is a rectifier. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A movable core for moving a movable contactor equipped with contacts for opening and closing main circuit terminals, a base to which this movable core is adhered, and a pair of rails that are fixedly disposed in an opening provided at the bottom of this base. a fixed iron core that faces the movable iron core and attracts the movable iron core; a guide member that is provided on the fixed iron core and has an engaging portion with the rail member; and a guide member that is combined with the fixed iron core. an operating coil that generates a predetermined excitation force, a control circuit section that controls the magnetic flux generated by the operating coil, a coil terminal that applies an alternating current voltage from a power source to this control circuit section, and the movable iron core and the fixed iron core. A changeover switch section that switches the control circuit section in order to change the current flowing through the operation coil during suction and steady state, and a switch section that is made into a container for mold casting and includes the operation coil, control circuit section, coil terminal, and changeover switch section. In the electromagnetic switch, the electromagnetic switch consists of a coil case that houses the coil case and is fixed to the rail member, and a coil cover that covers the top surface of the coil case, and the coil case includes the operating coil, the coil terminal, the changeover switch section, and the control. A cutout groove for guiding a lead wire electrically connected to the circuit section and a protrusion for fixing the coil cover are provided, and the coil cover is fixed to the coil case by fitting with a protrusion on the coil case. An electromagnetic switching device characterized in that a hook portion is formed.