JPH0139608B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for opening and closing a self-demagnetizing contact in an electromagnetic contactor.

A conventional latch holding and operating mechanism capable of electromagnetically releasing the latch is shown in FIG. Here, the crossbar 1 of the electromagnetic contactor (not shown) opens the main contacts in conjunction with this when the movable core is about to return due to the deenergization of the closing electromagnetic coil of the electromagnetic contactor. However, the cylindrical movable iron core 2 is pushed downward by the resilient spring 3 and is separated from the upper cylindrical fixed iron core 4, so the latch shaft 5 in the latch holding/operating mechanism Latch pawls 7, 7, which are provided inside the latch spring 6 with their tips open and resiliently supported, protrude outward from the slit 5a of the latch shaft 5 and are engaged with the fixed iron core 4. This prevents the latch shaft 5 from rising and maintains the latch engagement state. Next, in the tripping operation, when the tripping coil 8 disposed around the latch holding/operating mechanism is energized, the movable iron core 2 is urged upward against the spring 3, and the latch claws 7, 7 can be pushed inside the latch shaft 5,
The latch shaft 5 receives the elasticity applied to the crossbar 1, and
Only when the crossbar 1 is raised against the bias spring 6 is the crossbar 1 allowed to rise, and the main contacts of the electromagnetic contactor are opened. While the crossbar 1 is rising, a contact (not shown) supplying voltage to the tripping coil 8 is opened, so that the movable core is lowered by the force of the spring 3 and returns to its original state (FIG. 8).
In addition, during the lowering process of the crossbar 1, the contacts (none of which are shown) that supply voltage to the closing coil open, and when the latch is engaged and the latch is released, the voltage remains in both the closing and tripping coils. is currently not being supplied.

In such a conventional latch holding/operating mechanism, a series of latch operating mechanisms are located inside the tripping coil 8, so when a failure occurs, it cannot be detected from the outside, and if the coil 8 burns out, it cannot be detected. ,
Due to the deformation of the above coil, the latch claws 7, 7 and the movable iron core 2
If it is tied up, it cannot be manually released from the outside.

Further, since the crossbar 1 and the latch shaft 5 are not connected, even if the crossbar 1 moves backward, the movement of the latch shaft 5 is delayed, and there is a risk that the latch will not be engaged, resulting in so-called mislatching. This is because this latch holding/operating mechanism has a self-demagnetizing contact structure. In other words, since voltage can be applied to the closing coil of the electromagnetic contactor through the above-mentioned self-demagnetizing contact, voltage continues to be supplied until near the final end of the stroke of lowering the crossbar 1, and the self-demagnetizing contact After the power is cut off (the power supply is cut off), the movable core and crossbar 1 move with momentum to the end of the core stroke, but if the latching action by the latch pawl does not work during that time, the spring will trip. The crossbar begins to rise due to the force, and the self-demagnetizing contact closes while the crossbar 1 is rising. This supplies voltage to the closing coil, causing the crossbar 1 and the movable core to move downward again, so that the process repeats. Causes flapping. This causes accidents such as burnout of the coil. Also,
Since the self-demagnetizing contact is carried out by the crossbar 1, it must be distributed within the core stroke, so there is no difference between the core stroke and the stroke of the self-demagnetizing contact. Adjustment is complicated and there is a limit to the breaking capacity.

This invention is based on the above circumstances, and is an electromagnetic contact that incorporates a latch mechanism externally to the tripping coil, enables manual operation, eliminates fluttering operation caused by mislatches, and improves the breaking performance of the self-demagnetizing contact. It is intended to provide a latch mechanism in the device.

The present invention will be specifically explained below based on the embodiments shown in FIGS. 1 to 7. FIG. 1 shows the state in which the latch is disengaged, and in the figure,
Reference numeral 11 denotes a casing of the latch mechanism, and a solenoid coil 13 for latch tripping is attached to the inner upper part of the casing via a yoke 12, and is fixed with a set screw 14. Above solenoid coil 1
Inside the fixed core at the center of 3 is a rod-shaped movable core 15.
are arranged and resiliently supported by a compression coil spring 16. The movable iron core 15 is connected to the first latch member 1 via a pin 17 and a slit 18c.
The first latch member 18 is pivotally supported in the casing 11 by a pivot 19, and the movable iron core 15 is connected to the fixed iron core by a compression coil spring 20 interposed between the first latch member 18 and the yoke 12. It is rotationally biased in the direction of pulling it out. An arm 18a for engaging and holding is formed at the lower end of the first latch member 18, and rotation of the rear surface 18d of the arm is regulated by the tip 21a of the latch operating member 21.
The latch member 18 is located in the position shown. The latch operating member 21 is connected to the casing 1 by means of a pivot 22.
1, and the mounting frame 56 is fixed to the yoke 12 with screws 62.
(The same applies to the pivot 19) Also, a connecting arm 23 is pivotally supported in the middle by a pin 24. The housing 54 (FIG. 5) is fixed to the mounting frame 56 with screws 52 and 60.

The connecting arm 23 has an engaging portion 23a at its lower end, which includes an electromagnetic contactor (not shown).
A crossbar 1 (FIGS. 1 and 5) is engaged and connected. A second latch member 26 (FIG. 3), which is parallel to the latch operating member 21 and pivotally supported on the same pivot 22, has an engaging portion 26a at its tip, which engages the first latch. Same pivot 19 on member 18
It is removably engaged with an engaging claw 27 which is pivotally supported by. The engaging pawl 27 is connected to the first latch member 1.
8 and is rotationally biased in the direction of engagement with the engaging portion 26a.

Further, at the upper end of the engagement claw 27, a contact portion 27a is provided.
are integrally protruded. This contact portion 27a is
Facing the stopper part 18b protrudingly formed on the first latch member 18, when the engaging claw 27 engages with the second latch member 26, a predetermined gap G is maintained between the engagement claw 27 and the stopper part 18b; On the other hand, when the first latch member 18 rotates to the latched position, it is arranged so that it is rotated against the stopper 18b.

The second latch member 26 has a V at its intermediate portion.
A groove 26b is formed, and the lower end of the mover 29a of the self-demagnetizing B contact 29 is brought into contact with this groove. The movable element 29a can move up and down along a guide 30 formed in the casing 11, and is supported by a compression coil spring 31 to press downward. A movable contact 29b is supported by the movable element 29a in an upwardly resilient manner by a compression coil spring, and the movable contact 29b is supported by the movable element 29a.
A fixed contact 29c is located above the contact point 9b.
is arranged in a state where it is attached to the fixed contact 33.

Further, a tripping a contact 34 is formed to interlock with the latch operating member 21 (FIG. 5). That is, a guide 35 is formed in the casing 11 on the side opposite to the b contact 29, and the guide 35
A movable element 34a is provided so as to be movable up and down along the latch operation member 21.
are commonly supported on a shaft 24. The above a contact 34
Although not shown in detail in the figure, the mover 34
A circuit is prepared so as to turn on the switch and energize the solenoid coil 13 when a is directed downward;
Also, when the temperature rises, the switch is turned off.

Further, the second latch member 26 is integrally provided with an interlocking arm 26c (FIG. 6) extending from the side to the upper side of the latch operating member 21, and this is attached to the distal end side of the latch operating member 21. It is positioned so as to be pushed up by the back portion 21b.

In such a configuration, first, the operation of the circuit configuration shown in FIG. 9 will be explained. When the magnetic contactor closes the push button ON, the closing coil MC is energized through the self-demagnetizing b contact 29, and the latch is engaged. Almost at the same time as the latch is engaged, the tripping a contact 34 closes, and after the latch is engaged, the self-demagnetizing b contact 29 opens, and the closing coil MC is deenergized. This state continues until the latch is released. When the pushbutton OFF is closed, the tripping solenoid coil MT, 13 is energized through the closed tripping a contact 34, releasing the latch engagement, opening the tripping a contact 34, and self-demagnetizing the b contact. Perform closing. Next, as shown in FIGS. 1, 3, and 5, when the crossbar 1 of the electromagnetic contactor is raised by the pressing force of a tripping spring (not shown), the mechanical part automatically The demagnetizing b contact 29 is closed, and the solenoid coil 13 is deenergized. In this case, the latch operating member 21 is pushed up by the upward force of the crossbar 25 and the arm 18 of the first latch member 18
It is in the unlatched position (FIG. 1) where it is disengaged from the spring 20, and the spring 20 is held compressed. Further, the interlocking arm 26c is held upward by the tip back portion 21b. Further, the engaging pawl 27 engages with an engaging portion 26a at the tip of the second latch member 26 (FIG. 3). In this state, a gap G remains between the contact portion 27a and the stopper portion 18b.
Therefore, the closing coil of the electromagnetic contactor (not shown)
When a voltage is applied to the crossbar 1, the crossbar 1 moves in the direction of arrow D and pulls the connecting arm 23 downward. Along with this,
The latch operating member 21 is rotated downward about the shaft 22 and pulled to the lower end of the first latch member 18 (see FIG. 2). As a result, the first latch member 18 is tilted counterclockwise in the figure by the spring force of the spring 20, and its arm 18a wraps around above the free end 21a of the latch operating member 21, and the first latch member 18 and the latch are The operating member 21 is held in the engaged latched position. As the first latch member 18 tilts, the stopper portion 18b comes into contact with the abutting portion 27a of the engagement pawl 27, and pushes down the engagement pawl 27 counterclockwise in the drawing against the spring 28. As a result, the engaging pawl 27 engages the engaging portion 2 of the second latch member 26.
It comes off from 6a. This operation is performed by the stopper portion 18b.
Since there is a gap G between the contact portion 27a and the contact portion 27a, this is performed with a delay. When the engagement claw 27 is disengaged, the second latch member 26 is pressed downward by the spring 31 via the movable element 29a, so its front end is lowered as shown in FIG. As a result, the self-demagnetizing b contact 29 is connected to the second latch member 26.
is switched off during the initial downward phase of .

On the other hand, the tripping a-contact 34 is simultaneously closed when the latch operating member 21 engages with the first latch member 18 and is held in the latched position.
That is, since the mover 34a of the a contact 34 is connected to the crossbar 1 together with the latch operating member 21 via the shaft 24, when the crossbar 1 pulls the latch operating member 21 downward, it simultaneously slides downward and its It is switched on in the terminal downward phase.
The above state is as shown in FIG.

When the voltage applied to the closing coil of the electromagnetic contactor is removed, the biasing force applied to the crossbar 1 is released.
The crossbar 1 is now in a state where it can be raised by the spring force, but as is clear from FIG. 2, the arm 18
the free end 2 of the latch operating member 21 by the tip of a.
Since 1a is prevented from rising, crossbar 1 does not move. Therefore, the tripping a contact 34 is placed in the on state.

In the above state, when the solenoid coil 13 is energized, the movable iron core 15 operates against the spring 16 and pulls the first latch member 18 through the pin 17 against the spring 20. Tilts clockwise. Accordingly, the arm 18a is disengaged from the free end 21a of the latch operating portion 21, and the first latch member 18 returns to the unlatched position. Therefore, the crossbar 1 rises due to the restoring force of the tripping spring (not shown), so the connecting arm 23 rises,
The latch operating member 21 is pushed up, and the second latch member 26 is accordingly pushed up. Here, since the engaging claw 27 is given a counterclockwise rotational force in the figure by the spring 28, the engaging portion 26a and the engaging claw 27 are engaged with each other. In the process of raising the latch member 26, the a contact 34 first opens and closes, and the b contact 29 closes at the end. Therefore, even if the solenoid coil 13 is de-energized, the arm portion 18a of the latch member 18 will remain at the free end 18a of the latch operating member 21.
The state shown in Figure 1 is maintained.

In addition, at the time of closing, the engagement portion between the first latch member 18 and the latch operating member 21 needs to allow appropriate overrun. Since this is closely related to the stroke of the crossbar 15 of the electromagnetic contactor, it is necessary to make adjustments including manufacturing and assembly errors of these latch mechanisms. Therefore, in this embodiment, it is preferable to insert a spacer 53 between the casing 11 and the housing of the electromagnetic contactor.

As described in detail above, this invention has a movable iron core 15.
Since the operating stroke of the crossbar 1 can be set without being subject to limitations on the operating stroke of the crossbar 1, all conventional problems caused by this can be solved. Further, the solenoid coil 13 is not deenergized until after the latch operating member 21 is disengaged from the latch member 18. Therefore, input errors are eliminated. Furthermore, even in the event of a failure, many advantages can be achieved, such as ease of repair, inspection, and parts replacement of the latch member and latch operating member.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view showing one embodiment of the present invention, FIG. 2 is a longitudinal sectional side view of the same showing another state, and FIGS. 3 and 4 are B-B in FIG. 6, which will be described later.
5 and 6 are sectional views taken along lines EE and FF in FIG. 1, and FIG. 7 is a sectional view taken along line C-C in FIG. FIG. 8 is a circuit diagram of the coil and contacts, and FIG. 9 is a sectional view of the main parts of the conventional device. 1...Crossbar, 11...Casing, 13...
...Solenoid coil, 15...Movable iron core, 18...
...first latch member, 21...latch operation member,
26... Second latch member, 27... Engaging claw, 2
9...B contact for self-demagnetization, 34...A contact for tripping.

Claims (1)

[Claims] 1 Equipped with a tripping coil for opening and closing the main contact, which is combined with an electromagnetic contactor that opens and closes the main contact by displacing a crossbar biased in one direction by a tripping spring by a closing coil. In the latch mechanism, a latch operating member is rotatably attached to the casing at one end and the crossbar is connected to the intermediate portion thereof, and the latch operating member is removably engaged with the other end of the latch operating member, and a tripping coil is connected to the latch operating member. a first latch member that is displaced by bias to a position where it disengages from the latch operating member; a self-demagnetizing b that is interlocked with the latch operating member and demagnetizes the closing coil by its displacement; a second latch member for controlling the contact; this second latch member is removably engaged with the mover of the self-demagnetizing b contact; the second latch member is driven by the first latch member after being displaced and engaged with the latch operating member;
1. A latch mechanism for an electromagnetic contactor, comprising an engaging pawl that is disengaged from a latch member.