JPS6210915Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a vacuum switch opening/closing mechanism, in particular, a vacuum switch configured to be in a normally open state (always trying to open), such as in a changeover switch for a tap changer on load, via a bell crank. This invention relates to an improvement in the opening/closing mechanism that opens and closes with a cam.

As an example of this type of opening/closing mechanism, the one shown in FIG. 1 is well known. In the figure, 1 is a vacuum switch having a fixed contact bar 11 and a movable contact bar 12, and 2 is a first vacuum switch provided on the movable contact bar 12.
A spring receiver 3 is loosely inserted between the engaging flange 121 and the second engaging flange 122 of the vacuum switch 1. 4 is a contact pressure spring inserted between the spring receiver 2, 4 is an opening pressure spring inserted between the stationary object 9 and the spring receiver 2, and 5 is an opening pressure spring to keep the vacuum switch 1 in a normally open state. A bell crank is pivotally connected to a fixing pin 6, 7 is a plate cam having irregularities on its outer peripheral surface, and 8 is a cam shaft. The bell crank 5 has a first arm 51 and a second arm 52 that are substantially perpendicular to each other around the fixed pin 6, and the first arm 51 is rotated by a counterclockwise movement of the bell crank 5. 2 and drive upward. Further, the second arm 52 is arranged so that a cam follower 521 provided at its tip can follow the cam 7.

A perspective view of the bell crank 5 is shown in FIG. The opening spring 4 has a spring force greater than the self-closing force of the vacuum switch 1, and this spring force is transmitted to the movable contact rod 12 and the bell crank 5 via the spring receiver 2, thereby The movable contact rod 12 receives a driving force in a downward direction, and the bell crank 5 receives a driving force in a clockwise direction. Since the movable contact rod 12, which has only vacuum self-closing force as a drag force, cannot resist the spring force of the opening spring 4, the bell crank 5 is located at the position where this spring force is supported, that is, the cam follower 5.
21 comes into contact with the cam 7 and the bell crank 5 has descended to the position where it no longer rotates clockwise. That is, the vacuum switch 1 is connected to the bell crank 5.
Unless the spring support 2 is supported, the terminal is in a so-called normally open state in which it always attempts to open.

Thus, when the cam follower 521 is in the recess of the cam 7 (the figure shows this state)
In this case, the bell crank 5 is at its extreme clockwise rotation, the movable contact bar 12 is at its downward extreme, and the vacuum switch 1 is at its maximum opening. The cam 7 rotates from this, and its convex portion becomes the cam follower 52.
1, the bell crank 5 starts to rotate counterclockwise, and as a result, the spring receiver 2 starts to rise while compressing the contact opening push spring 4, and the movable contact rod 12 also starts to rise due to the vacuum self-closing force. . When the movable contact bar 12 comes into contact with the fixed contact bar 11, only the spring receiver 2 is then raised while also compressing the contact pressure spring 3. When the cam follower 521 reaches the top of the convex portion of the cam, the counterclockwise movement of the bell crank 5 stops, the rise of the spring receiver 2 also stops, and the closing operation of the vacuum switch is completed. The vacuum switch 1 maintains a closed state under a contact load that is a combination of the vacuum self-closing force and the spring force of the contact pressure spring 3.

However, in such a conventional opening/closing mechanism, the height of the vacuum switch, the height of the spring part, and the height of the bell crank are arranged in series, which inevitably increases the size of the device. .

The present invention has been developed to eliminate such drawbacks, and the height of the spring portion is increased by engaging and attaching the first arm of the bell crank to the arm protruding from the spring holder toward the vacuum switch. To provide an opening/closing mechanism for a vacuum switch whose overall size is reduced by arranging the height of the vacuum switch and the height of the bell crank in parallel.

Hereinafter, details of the present invention will be explained with reference to FIGS. 3 to 5 showing one embodiment of the present invention. In the figure, 1, 11, 12, 121, 122, 3, 4,
5, 51, 52, 521, 6, 7, 8, are the same as in FIG. Reference numeral 13 denotes a spring holder, and a support arm 131 projects from the outside of the opening spring 4 toward the vacuum switch 1.
It has a U-shape with a supporting arm 131.
An engagement pin 132 is provided at the tip. and,
By engaging the engagement pin 132 with the engagement groove 511 provided at the tip of the first arm 51 of the bell crank 5, the engagement force of the bell crank 5 to the spring receiver 13 is achieved. ing. Reference numeral 14 indicates a unit base that can be attached to and detached from this mechanism base, and 15 and 16 indicate an insulating frame that stands up on this unit base 14 and a holding plate attached to its end.
is attached to this holding plate 16. 17 guides the lower end of the movable contact bar 12 of the vacuum switch, and when the movable contact bar 12 descends by a predetermined stroke, it comes into contact with the engaging collar 122 and prevents the movable contact bar 12 from further descending. The stopper 18 is a frame body that fixes the stopper 17 to the unit base 14. 181 is a guide groove that guides the engagement pin 132 of the spring receiver so that it moves up and down without swinging left and right.

As explained above, in the opening/closing mechanism of the present invention, although the point of force applied to the spring receiver of the cam follower has moved slightly, there is no substantial change in the combination of other components. It goes without saying that the vacuum switch can operate in the same manner as described in the conventional embodiment shown in the figure, that is, if the cam follower is in the concave part of the cam, the vacuum switch is opened, and if it is in the convex part, the vacuum switch can be closed. do not have.

According to the opening/closing mechanism of the present invention, the engagement force point of the bell crank to the spring receiver is pulled up to the vacuum switch side, and the height of the bell crank and the height of the spring part are arranged in parallel, so that the entire device is The effect is that the height can be reduced.

In the embodiment, a case has been described in which a pressure spring for contact pressure is provided, but this may be omitted if the contact load is only a vacuum self-closing force. In addition, a pressure spring for contact pressure was inserted between the movable contact rod and the spring receiver, but
Alternatively, it may be inserted between the movable contact rod and a stationary object. In this case, it is necessary to make the spring force of the opening pressure spring larger than the sum of the self-closing force of the vacuum switch and the spring force of the contact pressure spring.

In addition, in the embodiment, the vacuum switch, the spring receiving contact pressure spring, and the contact opening pressure spring are assembled on the unit base 14 which is detachable from the mechanism base 9, so that they can be easily replaced all at once. If there is no need for replacement, the unit base 14 may be omitted and these may be directly attached to the mechanism base 9. In this case, the stopper 17 below the unit base 14 can be omitted, or the engagement groove with one end open in the first arm of the cam follower can be used as an engagement hole. In the case of an engagement hole, there is no need to provide an engagement pin guide groove in the frame.

Further, in the embodiment, a U-shaped integrally molded spring bearing is used, but instead, the spring bearing 13 and the first arm 51 of the bell crank 5 are connected by a link 19 as shown in FIG. You can. However, a U-shaped spring holder can be easily manufactured by bending an iron plate, and has fewer parts, so it is more practical.

Further, the engagement pin provided on the spring receiver can be attached outward, but in the case of caulking attachment, it is more advantageous to have the engagement pin facing inward.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a vacuum switch opening/closing mechanism according to the conventional method, Fig. 2 is a partial perspective view of Fig. 1,
FIG. 3 is a configuration diagram showing an embodiment of the vacuum switch opening/closing mechanism according to the present invention, and FIG.
FIG. 5 is a sectional view taken along the - line in FIG. 3, and FIG. 6 is a configuration diagram showing another embodiment of the vacuum switch opening/closing mechanism according to the present invention. In the figure, 1 is a vacuum switch, 11 is a fixed contact bar, 12 is a movable contact bar, 121 is a first engagement collar, 122 is a second engagement collar, 3 and 4 are springs, and 5 is a bell crank. , 7 is a plate cam, 9 is a stationary object, 13 is a spring receiver, and 131 is a support arm. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A movable and fixed contact bar, and a first contact bar provided on the side of the movable contact bar near the fixed contact bar.
a vacuum switch fixed to a stationary object, the vacuum switch having an engaging collar and a second engaging collar provided at a predetermined distance from the first engaging collar;
a spring receiver having a support arm that is engaged with the engagement collar and extends in the direction of the first engagement collar; a first arm that is connected to the distal end of the support arm; a bell crank having a second arm having a cam follower at an angle of A vacuum switch opening/closing mechanism comprising a spring and a second spring interposed between the vacuum switch and the spring receiver. (2) Vacuum switch, spring holder, first spring and second spring
The spring is assembled in one piece and is attached to the first bell crank.
The opening/closing mechanism for a vacuum switch according to claim 1, which is configured to be detachably attached to the arm of the user.