JPS5913730Y2 - contact device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a contact device in an electromagnetic contactor or the like.

Generally, when a magnetic contactor etc. is turned on, a jumping phenomenon always occurs when the fixed contact part and the movable contact part come into contact at a certain speed.
In order to eliminate this drawback, which is accompanied by severe wear and tear due to the spark phenomenon that repeatedly opens and closes in short bursts, attempts are made to increase the contact pressure or reduce the weight of the movable contact part, but by making the movable contact thinner, mechanical It had the disadvantage of being weak.

In addition, in view of the above-mentioned drawbacks, there are some devices in which the movable contact is made of an elastic material, but if the applied current becomes large, the thickness of the movable contact must be increased, which makes it impossible to maintain elasticity.

Furthermore, there are some devices in which the back surface of the contact portion is held down by a buffer leaf spring, but the structure for preventing the movable contact from falling off from the buffer leaf spring is complicated.

For example, some devices have a cutout at both ends of the center of the movable contact, and a buffer leaf spring is provided with a cutout that engages with both longitudinal ends of the cutout to prevent the movable contact from falling off. However, in this case, a U-shaped bracket must be embedded in the lower part of the window hole of the movable contact support rod to prevent sliding friction with the bent portion of the leaf spring, making the overall structure complicated. Not only this, but also as described above, since the notches are provided at both ends of the center of the movable contact, there is a drawback that the effective cross-sectional area is reduced.

The present invention aims to provide a contact device that eliminates these drawbacks.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 4.

In the figure, 1 is a movable contact with contacts 1a fixed to both ends and a recess 1b formed in the center; 2 is a fixed contact; the contact 2a is provided opposite the contact 1a of the movable contact 1;

Reference numeral 3 denotes a buffer leaf spring made of an elastic material, which has a recess 3a in its center that approximately fits into the central recess 1b of the movable contact 1;
Both side pieces extend in a semicircular arc shape, and both side tips 3C are rounded so as to come into contact with the back surface of the contact portion of the movable contact 1, and a projection 3b is provided in the central recess 3a.

Reference numeral 4 denotes a support rod having a window hole 4a, into which the movable contact 1 is assembled, and the central recess 3a of the buffer leaf spring 3 is fitted onto the recess 1b.

Next, the contact spring 5 is fitted between the protrusion 3b of the central recess 3a of the buffer leaf spring 3 and the protrusion 4b provided at the other end of the window hole 4a of the support rod 4.

The pressure of the buffer leaf spring 3 is made relatively smaller than that of the contact spring 5, and there is a gap smaller than the contact d between the lower surface of the central recess 3a of the buffer leaf spring 3 and the upper surface of the central recess 1b of the movable contact 1. g.

Here, entering contact will be explained.

Generally, when an electromagnetic contactor or the like is turned on, the support rod 4 is lowered, the movable contact 1 contacts the fixed contact 2, and then the support rod 4 is further lowered a certain distance.

This is to provide a margin for reliable contact even if the contact is worn out due to opening and closing, and the fixed distance by which the contact is lowered after contact is called contact entry d.

Next, the operation of the device configured as described above will be explained.

First, the support rod 4 is driven by the operation of an electromagnetic core (not shown), and the contact 1a of the movable contact 1 comes into contact with the contact 2a of the fixed contact 2.

In this case, if the buffer leaf spring 3 is not present, the movable contact 1 collides with the fixed contact 2 at the instant of contact and receives a repulsive force.

The contact spring 5 has a strong elasticity so that the contact pressure at the time of final closing is greater than a certain value, so the contact spring 5 cannot absorb the impact at the time of closing, and a jumping phenomenon inevitably occurs.

In the present invention, by interposing the buffering leaf spring 3, which has a weaker elasticity than the contact spring 5, between the movable contact 1 and the contact spring 5, the movable contact 1 tends to be bounced back by the instantaneous impact when the contact spring 5 is turned on. The shock absorbing leaf spring 3 absorbs the impact force with its weak elasticity, absorbs and alleviates the impact force, and prevents the jumping phenomenon.

When the contact spring 5 is inserted more deeply, the gap g between the buffer leaf spring 3 and the movable contact 1 is reduced, and contact pressure is applied by the elasticity of the contact spring 5 at the final insertion.

In this case, the elasticity of the contact spring 5 is significantly stronger than that of the buffer leaf spring 3, and if the contact is large, the gap g may eventually become zero.

Further, the movable contact 1 and the buffer leaf spring 3 are held together by the fitting of the respective recesses 1b and 3a, and the integrated movable contact 1 and the buffer leaf spring 3 are connected to the buffer leaf spring 3.
The protrusion 3b of the central recess 3a is supported by the contact spring 5 fitted to the protrusion 4b of the support rod 4, and the movement in the left-right direction in the figure is suppressed (t), and the elastic force of the contact spring 5 causes the buffer plate spring to 3, the movable contact 1 is always pressed downward in FIG. 1, thereby preventing the movable contact 1 from falling off.

To explain the action of the contact spring 5 here, the upper base end of the contact spring 5 is fitted and held by the projection 4b, and its tip engages with the projection 3b of the buffer leaf spring, elastically pushing the projection 3b. The movable contact 1 is elastically pressed downward via the push-down buffer leaf spring 3.

In this state, a locking action by frictional force acts between the movable contact 1 and the lower surface of the window hole 4a.

Further, since the base of the contact spring 5 is fitted and held by the protrusion 4b, an elastic return force is exerted to return the contact spring 5 to the reference position shown in FIG. Acts on child 1.

If vibration or external force is applied to the movable contactor 1, causing it to shift in the left-right direction in FIG. 1, the contact spring 5 will be bent or deformed as shown in FIGS. A force that attempts to return the tip to the state shown in Figure 3a acts as shown by arrow B or arrow C, and this returning force causes the buffer leaf spring 3 and the movable contact 1 to return to the reference position shown in Figure 1. being pulled back.

That is, the elastic return force of the contact spring 5 causes the movable contact system, which is stronger than the movable contact 1 and the buffer leaf spring 3, to
It serves to elastically hold the movable contact 1 at the reference position shown in the figure, and the movable contact 1 is constantly corrected for misalignment and prevented from falling off.

The recessed part 1b of the movable contact 1 and the recessed part 3a of the buffer leaf spring 3 are formed in a shape that allows them to be overlapped with some margin in the vertical and horizontal directions, so that when they are overlapped, mutual displacement is reduced.

In the open state of the movable contact, the recess 3a rises due to the elasticity of both sides of the buffer leaf spring 3, creating a gap g between the recesses 1b and 3a.
It is made sufficiently larger to prevent the fitting between both recesses from coming off.

In the embodiment shown in FIG. 1, both the recesses 1b and 3a are formed in a trapezoidal shape, and in this case, in the open state, the fitting between the two recesses becomes loose, but at this time, the contact spring 5 and the buffer leaf spring The elasticity of the movable contact 3 presses the lower surface of the movable contact against the lower surface of the window hole of the support rod 4, and a frictional force acts on the contact portion to prevent displacement.

It is better for the slope of the vertical side of the trapezoidal shape of the double concave part to be close to vertical in order to maintain the fit, but for convenience of processing etc., it is optional to set an angle within the range that does not impair the fit conditions as mentioned above. It is.

In the contactor inserted state, the movable contactor 1
The contact 1a of the fixed contact 2 is pressed against the contact 2a of the fixed contact 2, and the frictional force between the two contacts prevents displacement.

Further, even if a misalignment occurs, the misalignment is corrected by fitting.

In this way, no matter what state the contact is in, the frictional force always acts to prevent it from slipping, and the elastic restoring force of the contact spring and the engagement of the buffer leaf spring 3 and the movable contact 1 act to return it to its reference position. , preventing it from slipping or falling off.

It should be noted that although the drawings of the embodiment are shown in a somewhat exaggerated manner, the shape can be modified as desired within the range that satisfies the above purpose, and is not limited to the shape of the embodiment.

As described above, the present invention presses and holds the movable contact 1, which is placed opposite the fixed contact 2 in the window hole 4a provided in the movable contact support rod, by the contact spring 5 via the buffer leaf spring 3. In this case, the movable contact 1 has a concave part 1b formed by bending its central part and is positioned at one end of the window hole, and a contact 1a is provided at both ends of the movable contact 1. A recess 3a that fits into the recess 1b of the movable contact is formed, and the extended end portions 3C of both sides thereof are connected to the contact 1 of the movable contact.
The central concave portion 3 of the buffer leaf spring 3 is brought into contact with the back surface of the
A protrusion 3b is formed inside a, and this protrusion 3b and the window hole 4a
A contact spring 5 is fitted between the protrusion 4b provided at the other end of the contact spring 5, and the contact spring 5 is fitted between the center of the movable contact 1 and the center of the buffer leaf spring 3 before the contact is inserted. A gap g smaller than when the contact is inserted is provided, and the elasticity of the buffer leaf spring is made smaller than that of the contact spring 5 so that the gap g is reduced when the contact is inserted. In addition, in the final charging stage, contact pressure is obtained due to the relatively strong pressure of the contact spring, and the quality is stabilized. , the movable contact 1
By fitting the four parts 1b with the recesses 3a of the buffer leaf spring 3 and supporting the protrusion 3b provided on the buffer leaf spring 3 by the contact spring 5, the movable contact 1, the buffer leaf spring 3, and the contact spring/ The movable contact 5 can be prevented from falling off by being fitted in both cases when the contact is inserted and released.
Since this can be done without particularly providing a sliding portion of the support rod 4, there is no fear of wear of the movable contact support rod 4, and a low-cost contact device with a simple structure and high mass productivity can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view of the main part of the embodiment of the present invention when opened;
Fig. 2 is a longitudinal sectional side view of the main part when the contact is closed, Fig. 3 is an explanatory diagram showing the deformed state of the contact spring, and Fig. 4 is a longitudinal sectional side view of the main part showing the state in which the movable contact is shifted when the contact spring is opened. It is. 1: Movable contact, 2: Fixed contact, 3: Buffer leaf spring,
4: Support rod, 5: Contact spring.

Claims (1)

[Scope of utility model registration request] A movable contact 1 placed opposite a fixed contact 2 in a window hole 4a provided in a movable contact support rod is pressed and held by a contact spring 5 via a buffer leaf spring 3. is bent at its center to form a recess 1b, which is positioned at one end of the window hole, and contacts 1 are provided at both ends of the recess 1b.
a is provided, and the buffer leaf spring 3 is provided with a recess 1 of the movable contact.
forming a recess 3a that fits into the recess 3a, and bringing the extended end portions 3C of both sides thereof into contact with the back surface of the contact 1a of the movable contact;
A protrusion 3b is formed in the central recess 3a of the buffer leaf spring 3, and a contact spring 5 is fitted between this protrusion 3b and a protrusion 4b provided at the other end of the window hole 4a to make contact. Before inserting the contact, a smaller gap g is provided between the center of the movable contact 1 and the center of the buffer leaf spring 3 than when the contact is inserted, and when the contact is inserted, the buffer leaf spring is A contact device characterized in that the elasticity of the contact spring 5 is smaller than that of the contact spring 5.