JPH0635352Y2 - Arc horn fixing device for circuit breaker - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a device for fixing an arc horn attached to a fixed contactor for guiding an arc generated at the time of interruption to an arc extinguishing chamber in a small circuit breaker such as a circuit breaker for wiring.

2. Description of the Related Art Conventionally, as a structure for attaching an arc horn to a fixed contact, as described in Japanese Utility Model Laid-Open No. 62-9341, a structure by caulking is known. This is made by bending the lower end of the arc horn into a mounting seat, and inserting the punched-out part punched into the fixed conductor of the fixed contact into the hole for caulking in this mounting seat, and pushing the head wide open. The horn is fixed to a fixed conductor.

[Problems to be solved by the device]

However, such a conventional structure has the following drawbacks. (1) Since a space for mounting the arc horn mounting seat on the fixed contactor is required, the space for the screw for fixing the fixed contactor to the case is restricted, and it is difficult to employ it in a small circuit breaker. (2) In order to make the heights of the arc horn and the fixed contact uniform, it is necessary to make the fixed contact mounting portion of the fixed contact tall, which complicates the shape of the fixed contact. (3) The caulking portion is located inside the bent portion of the arc horn that covers the mounting seat, making caulking work difficult. Then, this invention aims at providing the arc horn fixing device of the circuit breaker which fixed the arc horn without caulking, and which eliminated the said defect.

[Means for Solving the Problems]

In order to achieve the above object, the present invention is a circuit breaker in which a fixed contact fixed to a case is provided with an arc horn that guides an arc generated at the time of interruption to an arc extinguishing chamber, and a hole is formed in the arc horn, A groove is provided on the surface of the case where the fixed contact is fixed, and the leg portion of the arc horn fitted into the fixed contact is inserted into the groove using the hole.

[Action]

According to the above structure, (1) the arc horn does not need a mounting seat, and therefore does not occupy a space with respect to the fixed contact. (2) Since the arc horn is fitted on the fixed contact without placing it on the fixed contact, the heights of the fixed contact and the arc horn can be made uniform without raising the fixed contact mounting portion of the fixed contact. (3) The caulking work is unnecessary, and the arc horn can be fixed only by fitting, so that the assembly is easy.

【Example】

An embodiment of the present invention will be described below with reference to FIGS. Here, FIG. 1 is a vertical sectional view of a circuit breaker (wiring breaker) equipped with the device of the present invention, FIG. 2 (A) is a plan view of the fixed contactor in FIG. 1, and FIG. B) is a side view thereof, FIG. 3 (A) is a side view of the arc horn in FIG. 1, FIG. 3 (B) is a front view seen from the arrow P direction, and FIG. 4 is a fixing in FIG. It is an exploded perspective view showing an assembling order of a contact child part. In FIG. 1, 1 is a fixed contactor integrated with a terminal plate 1a on the power source side, 2 is a movable contactor, 3 is a lead wire, 4 is a trip coil of an overcurrent trip device, and 5 is a terminal plate on the load side. 6 is an opening / closing mechanism, 7 is an operating handle, 8 is an arc horn attached to the fixed contact 1, 9 is an arc extinguishing chamber, and 10 is a case for accommodating all of them. When the operation handle 7 is operated in the left-right direction in the drawing, the movable contactor 2 opens and closes the fixed contactor 1 by the action of the opening / closing mechanism 6. The current flows in the route of fixed contact 1 → movable contact 2 → lead wire 3 → trip coil 4 → terminal board 5. When an overcurrent occurs, trip coil 4 detects it and opens / closes mechanism 6. The movable contactor 2 is operated to automatically open. that time,
An arc is generated between the fixed contact 11 and the movable contact 12, and the arc is guided to the arc horn 8 and drawn into the arc extinguishing chamber 9, where it is cooled and extinguished. The fixed contact 1 is fastened to the case 10 with screws 13. Now, the fixing structure of the arc horn 8 will be described below. In FIG. 2, the fixed contact 1 made of a rectangular conductor is bent into an S shape so that the terminal plate 1a is raised, and the screw 13
The intermediate portion provided with the screw hole 14 for screwing (FIG. 1) and the tip portion joined with the fixed contact 11 are the terminal plate portion.
The width is gradually narrower than 1a. Reference numeral 15 is a screw hole for connecting an external conductor (not shown) to the terminal board 1a. On the other hand, the arc horn 8 is made of an iron plate, and the tip of a rectangular plate punched with a convex hole 16 is chamfered into a chevron shape
The upper half portion 16a of the 16 is bent in a dogleg shape. As will be described later, the upper half part 16a of the hole 16 is a part for escaping the fixed contact 11 when the arc horn 8 is fitted into the fixed contact 1, and the lower half part 16b is a part for press-fitting the tip part of the fixed contact 1. The height dimension of the lower half portion 16b is slightly larger than the plate thickness of the fixed contact 1, but the width dimension B is a tight fit relationship with the width dimension A (Fig. 2) of the tip portion of the fixed contact 1. Is slightly smaller so that FIG. 4 shows the procedure for attaching and fixing the arc horn 8 to the fixed contactor 1. First, align the lower half portion 16b of the hole 16 of the arc horn 8 with the tip portion of the fixed contactor 1 and in the direction of arrow X. Press fit. Then, the fixed contact 11 is pushed in until it abuts on the stepped portion 1b of the fixed contact 1 while escaping the fixed contact 11 in the upper half portion 16a of the hole 16. Then, attach the fixed contact 1 to the arrow Y.
Direction 10 is inserted and fixed to the case 10, the arc horn 8 is provided on the surface 10a of the case 10 on which the fixed contact 1 is fixed.
A groove 17 is provided in a portion where the leg portion 8a is located. The width and depth of the groove 17 are slightly larger than the plate thickness of the arc horn 8 and the protruding height of the lower end from the fixed contact 1. Therefore, the leg portion 8a of the arc horn 8 is inserted into the groove 17 to bring the fixed contact 1 into close contact with the fixed surface 10a, and the case 1
Screw the screw 13 inserted from the back side of 0 through the hole 10b into the screw hole 14 and tighten. The electrical connection between the arc horn 8 and the fixed contact 1 is provided by the hole 16
It is secured by press-fitting the fixed contactor 1 in the width direction. Further, the mechanical fixing of the arc horn 8 is carried out by pressing the arc horn 8 with the fixed contact 1 in the vertical direction and sandwiching it with the groove 17 in the front-back direction. Arc horn 8 and fixed contact 1
The electrical continuity with may be obtained by pressing the fixed contact 1 against the lower edge of the hole 16 with the tightening force of the screw 13. In the above configuration, since it is not necessary to provide the arc horn 8 with a mounting seat, the mounting space for the fixed contact 1 in the front-rear direction is only the thickness of the arc horn 8. Further, since the caulking work is unnecessary and the arc horn 8 can be fixed only by fitting and inserting, the number of assembling steps is reduced and the work is facilitated.

[Effect of device]

According to this invention, since it is not necessary to provide a space corresponding to the mounting seat of the arc horn on the fixed contact, mounting of the arc horn in a small circuit breaker becomes easy. Further, since the caulking work is eliminated and the arc horn can be fixed only by fitting or inserting, the assembly is simplified and the arc horn can be assembled by an automatic machine.

[Brief description of drawings]

FIG. 1 shows an embodiment of this invention, FIG. 1 is a longitudinal sectional view of a circuit breaker equipped with the device of this invention, FIG. 2 (A) is a plan view of a fixed contactor in FIG. 1, and FIG. (B) is a side view thereof, FIG. 3 (A) is a side view of the arc horn in FIG. 1, FIG. 3 (B) is a front view seen from the arrow P direction, and FIG. 4 is in FIG. FIG. 6 is an exploded perspective view showing an assembling order of fixed contact portions. 1 ... Fixed contact, 2 ... Movable contact, 8 ... Arc horn, 8a ... Arc horn leg, 9 ... Arc extinguishing chamber, 10 ...
… Case, 10a …… The surface on which the fixed contact of the case is fixed, 1
6 …… Arc horn hole, 17 …… Groove.

Claims (1)

[Scope of utility model registration request] 1. A circuit breaker, in which a fixed contact fixed to a case is provided with an arc horn for guiding an arc generated at the time of interruption to an arc extinguishing chamber, a hole is formed in the arc horn, and a fixed contact of the case is fixed. An arc horn fixing device for a circuit breaker, characterized in that a groove is provided on a surface of the arc horn and a leg portion of the arc horn fitted into the fixed contact is inserted into the groove by using the hole.