JPH0322836Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to the prevention of damage to an electromagnetic contactor, particularly its changeover switch.

[Prior art]

FIG. 4 is a schematic cross-sectional view showing a conventional electromagnetic contactor. In the figure, 2 is a movable part, and 4 is a movable part 2.
This is a changeover switch provided below the changeover switch 4, and has a push rod 6 for changing the internal switch. The movable part 2 is configured to be movable in the directions of arrows a and b by an electromagnet (not shown), and the push rod 6 is similarly configured to be movable in the directions of arrows a and b.

The conventional electromagnetic contactor is constructed as described above, and the integrated movable part 2 is moved in the direction of arrow b by an electromagnet and comes into contact with the push rod 6 of the changeover switch 4.
The push rod 6 of the changeover switch 4 is pushed by the movable part 2 and moves in and out, thereby opening and closing the changeover switch 4 and controlling the excitation circuit of the electromagnet.

However, in conventional magnetic contactors, the movable part 2
Since the mass of the push rod 6 is about 100 to 1000 times the mass of the push rod 6, the push rod 6 is accelerated with a large amount of energy by the collision of the movable parts and is caused to vibrate. push rod 6
This vibration was transmitted to the internal switch, causing wear and tear on the switch's contact mechanism, etc. Furthermore, if the overshoot of the movable part 2 becomes larger than the stopper of the push rod 6, the push rod 6 is deformed and damaged at the collision surface with the movable part 2, which is a drawback.

[Summary of the idea]

This invention was made for the purpose of improving such drawbacks, and the movable part is equipped with a cylindrical pressing body having a flange-like projection and an axial slit at the end that engages with the edge of the through hole of the movable part. The press body is slidably inserted into the through hole of the selector switch toward the switch, and the pusher is biased by a spring with a spring force slightly greater than the load required to operate the push rod of the switch. To propose an electromagnetic contactor in which the push rod does not easily vibrate even when parts collide, and the collision surface of the push rod with the movable part is not deformed or damaged even if the movable part overshoots. It is.

[Example of idea]

FIG. 1 is a schematic explanatory diagram showing one embodiment of this invention, and numerals 2 to 6 are exactly the same as the conventional apparatus described above. Reference numeral 8 denotes a bottomed cylindrical pressing body, and the side of this pressing body 8 has a plurality of slits 9a, 9b in the vertical direction as shown in the exploded perspective view of FIG. 2 (see also FIG. 3). A pair of protrusions 10 are provided at the end of the push plate 8 toward the outside. A spring receiver, which will be described next, is fitted into the wide and shallow slit 9a. Further, the narrow and deep slits 9b provided on both sides of the two protrusions 10 apply elastic force to the cylindrical portions near both protrusions 10 in the direction of pushing them apart. 12 is a cross bar of the movable part 2, and a push plate 8 is provided at the part of the cross bar 12 that faces the push rod 6.
A through hole 14 is provided with a size that allows the insertion of the spring holder 16, and a spring receiver 16 is provided on the upper exit side of the through hole 14. A pressing body 8 is inserted into the through hole 14,
As shown in FIG. 3, a protrusion 10 of the pressing body 8 is engaged with the edge of the through hole 14. As shown in FIG. Further, a spring 18 is inserted between the spring receiver 16 of the cross bar 12 and the bottom of the pusher 8, and the pusher 8 is connected to the push rod 6.
The push rod 6 is urged in the direction with a force slightly larger than the load required to operate the push rod 6.

In the electromagnetic contactor of the present invention configured as described above, when the movable part 2 is driven by the electromagnet, the arrow b
The bottom surface of the press body 8 comes into contact with the push rod 6. When the press body 8 comes into contact with the push rod 6, the push rod 6 receives a strong force from the movable part 2, is pushed by the press body 8, and is pushed down in the direction b. Then, the push rod 6 is pushed down to a certain position, the changeover switch 4 is switched, and the lowering of the push rod 6 by the movable part 2 is stopped. Further, when the push rod 6 reaches the lower limit position and the movable part 2 overshoots, the push rod 6 that has stopped moving will be moved relative to the pressing body 8.
Compress the spring 18 while pushing it up in the direction a. In this way, the force applied to the changeover switch 4 is buffered, and the impact surface of the push rod 6 and the contact mechanism are prevented from being worn out or damaged.

In this case, elastic force is applied to the cylindrical portion near the projections 10 on both sides of the pressing body 8 to expand outward by the slits 9b as described above.
It slides in the axial direction inside the through hole 14 without any gap.
As a result, not only when the movable part 2 overshoots, but also at the moment when the pusher 8 contacts the push rod 6, only the axial force is applied without applying radial vibration to the push rod 6. The changeover switch 4 can be switched by transmitting the information.

[Effect of idea]

As explained above, this invention has a simple structure in which the pressing body is slidably provided on the movable part, a spring is provided between the pressing body and the movable part, and the pressing body is biased toward the push rod. This has the effect of suppressing the vibration of the push rod due to a collision, reducing the excessive load applied to the stopper of the push rod due to overshoot of the movable part, and extending the mechanical life of the changeover switch.

In addition, since the cylindrical part near the protrusion of the pressing body is given an elastic force that expands outward by the axial slit, the pressing body does not slip out of the through-hole, and accurately positioned. Furthermore, this elastic force allows the pressing body to fit into the through hole without any gaps, and slide along the axial direction without vibrating in the radial direction. As a result, according to the present invention, the force is transmitted between the movable part and the changeover switch via the pressing body that slides only in the axial direction, and an accurate and reliable buffering function is achieved. arise.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an embodiment of this invention, FIG. 2 is an exploded perspective view showing an embodiment of this invention, FIG. 3 is a partial view of FIG. FIG. 4 is a schematic explanatory diagram of a conventional electromagnetic contactor. In the figure, 2 is a movable part, 4 is a changeover switch, and 6
is a push rod, 8 is a press body, 9a and 9b are slits,
10 is a protrusion, 12 is a crossbar, 14 is a through hole,
16 is a spring receiver, and 18 is a spring. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] In an electromagnetic contactor equipped with a changeover switch that opens and closes a push rod by moving it in and out based on the drive operation of a movable part driven by an electromagnet to open and close a main circuit, A flange-like protrusion that is slidably disposed in a through hole provided in the movable part and slits formed in the axial direction on both sides of the protrusion apply elastic force in the radial direction to the cylindrical part near the protrusion. a cylindrical pressing body with a bottom, and a spring disposed within the pressing body, the other end of which is latched to the movable part to apply a spring force to the pressing body; An electromagnetic contactor characterized in that it is configured to buffer the force applied from the movable part to the changeover switch via the movable part.