JPH0751723Y2 - Arc horn fixing device for circuit breaker - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a structure for fixing an arc horn for guiding an arc generated during interruption to an arc extinguishing grid in a small circuit breaker such as a circuit breaker for wiring.

[Prior art]

Conventionally, as a structure for attaching an arc horn to a fixed contact, as described in Japanese Utility Model Application Laid-Open No. 62-9341, a structure by caulking is generally known. This is to bend the lower end of the arc horn into a mounting seat, insert the punched part punched into the fixed conductor of the fixed contact into the hole for caulking in this mounting seat, and push the head open to spread the arc horn. It is fixed to a fixed conductor.

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 interruption to an arc extinguishing grid. An arc horn composed of a flat portion and a leg portion fitted into the fixed contact, and an upper half portion for allowing the fixed contact on the upper surface of the fixed contact to escape and the fixed contact to be inserted into the leg portion. A hole consisting of a half part is formed, and a tongue-shaped piece to be brought into contact with the lower surface of the fixed contact is bent and bent at a right angle to the lower edge of the lower half part of the hole, while the fixed contact of the case is fixed. A groove for inserting the tip of the leg portion of the arc horn is provided on the surface, and the tip of the leg portion of the arc horn inserted into the fixed contactor through the hole is sandwiched between the groove and the tongue-shaped piece. It is intended to fix suppressed by the fixed contact.

[Action]

According to the above configuration, (1) the arc horn does not need a mounting seat, and therefore does not take up space with respect to the fixed contact. (2) Since the arc horn is not mounted on the fixed contact but is fitted into the fixed contact, the heights of the fixed contact and the arc horn can be made uniform without increasing 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】

First, an embodiment of the invention will be described 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 contactor 1, 9 is an arc extinguishing grid, 10 is a case for accommodating all of them, and the fixed contactor 1 is screwed to the case 10.
It is tightened with 13. In such a configuration, when the operation handle 7 is operated in the left-right direction in the figure, the opening / closing mechanism 6 works to move the movable contactor 2.
Opens and closes the fixed contact 1. Current is fixed contact 1 → movable contact 2 → lead wire 3 → trip coil 4 →
When a current flows through the path of the terminal plate 5 and an overcurrent is generated, the trip coil 4 detects this and the opening / closing mechanism 6 is operated to automatically open the movable contact 2. At that time, an arc is generated between the fixed contact 11 and the movable contact 12, but the arc is guided to the arc horn 8 and drawn into the arc extinguishing grid 9, where it is cooled and extinguished. 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 formed of a flat conductor (in this case, an iron plate) is composed of two parts rising from the upper surface of the fixed contact 1 and a leg 8b fitted into this fixed contact. As shown, a convex hole 16 is punched in the leg 8b, and the tongue 8a is bent and bent at a right angle to the lower edge of this hole, and the tip of a strip-shaped plate is chamfered into a chevron shape. It is configured by bending in a V shape near the portion 16a. As will be described later, the upper half portion 16a of the hole 16 is a portion for escaping the fixed contact 11 when the arc horn 8 is fitted into the fixed contact 1, and the lower half portion 16b is a portion for press-fitting the whole end portion of the fixed contact 1. The width dimension B of the lower half portion 16b has a tight fit relationship with the width dimension A (FIG. 2) of the tip portion of the fixed contact 1. FIG. 4 shows the procedure for fitting the arc horn 8 into the fixed contact 1 to fix it. First, the lower half portion 16b of the hole 16 of the arc horn 8 is aligned with the tip of the fixed contact 1, and the direction of the arrow X is indicated. Press into. Then, fix the fixed contact 11 to the upper half of the hole 16.
While escaping at 16a, push it in until it hits the stepped portion 1b of the fixed contact 1. Next, the fixed contact 1 is inserted in the direction of the arrow Y and fixed to the case 10. The surface 10a of the case 10 for fixing the fixed contact 1 is provided with a groove 17 in a portion where the leg portion 8b of the arc horn 8 is located, and further to this portion, a groove 18 is provided in a portion where the tongue 8a is located. Is provided.
Therefore, when fixing the fixed contact 1 to the case 10, the tip of the leg portion 8b of the arc horn 8 is inserted into the groove 17, and the tongue 8a is fitted into the groove 18 to fix the fixed contact 1 to the fixing surface 10a. The screw 13 inserted through the hole 10b from the back side of the case 10 into the screw hole 14 and tightened. 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 performed by pressing the fixed contact 1 for vertical movement of the arc horn 8 and sandwiching it by the groove 17 for longitudinal movement. If the arc horn 8 is largely tilted in the front-back direction (left-right direction in FIG. 1), there is a risk that the movable contact 2 will come into contact at the time of closing and the conduction between the contacts 11 and 12 will be lost, as can be seen from FIG. is there. Therefore, in the illustrated configuration, the tongue 8a is brought into contact with the lower surface of the fixed contactor 1, and even if there is a play between the leg portion 8b and the groove 17, the tongue 8a does not contact the lower surface of the fixed contactor 1. It is pressed down by and is prevented from falling in the front-back direction. The electrical connection between the arc horn 8 and the fixed contact 1 may be obtained by pressing the fixed contact 1 against the tongue 8a with the tightening force of the screw 13. Next, FIG. 5 shows a groove 18 in the case 1 for escaping the tongue 8a.
FIG. 5 (A) is a longitudinal sectional view of a fixed contact portion, and FIG. 5 (B) is a front view seen from the direction of arrow P. That is, in FIG. 5, the fixed contact 1 is bent by the thickness of the tongue 8a, and
18 is unnecessary. Further, FIG. 6 is a view similar to FIG. 5, showing an embodiment in which the same arc horn 8 is used even if the rating of the circuit breaker is increased. In the figure, a groove 1a for escaping the tongue 8a of the arc horn 8 is provided on the bottom surface of the fixed contact 1, and the tongue 8a is housed in this groove 1a. In this way, if the rating is increased and the plate thickness of the fixed contact 1 is increased, the fixed contact 1 is provided with the groove 1a so that the tongue piece 8a is housed in the groove 1a. 8 can be shared by the fixed contacts 1 having various plate thicknesses. According to the configuration described above, it is not necessary to provide the arc horn 8 with a mounting seat, so that the mounting space for the fixed contact 1 in the front-rear direction is only the thickness of the arc horn 8. In addition, the caulking work is unnecessary, and the arc horn 8 can be simply inserted and inserted.
Since it can be fixed, the number of assembling steps is reduced and the work becomes easier.

[Effect of device]

According to this invention, the space for mounting the mounting seat of the arc horn on the fixed contact is unnecessary, so that the mounting of the arc horn in a small circuit breaker becomes easy. Further, since the arc horn can be fixed only by fitting and inserting without caulking work, 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. 5 (A) is an exploded perspective view showing the order of assembling the fixed contact portion, FIG. 5 (A) is a longitudinal sectional view of a main part of another embodiment, and FIG. 5 (B) is a front view seen from the arrow P direction. FIG. 6A is a longitudinal sectional view of a main part of still another embodiment, and FIG. 6B is a front view seen from the arrow P direction. 1 ... Fixed contactor, 2 ... Movable contactor, 8 ... Arc horn, 8a ... Tongue, 8b ... Leg, 9 ... Arc extinguishing grid, 10 ... Case, 16 ... Arc horn Hole, 17 ……
groove.

Claims (1)

[Scope of utility model registration request] 1. A circuit breaker in which an arc horn that guides an arc generated at the time of interruption to an arc extinguishing grid is attached to a fixed contact fixed to a case, and one portion rising from the upper surface of the fixed contact and this fixed contact. An arc horn composed of a leg part to be fitted is formed of a flat plate conductor, and a hole composed of an upper half part for allowing the fixed contact on the upper surface of the fixed contact to escape and a lower half part for inserting the fixed contact is formed in the leg part. At the same time as forming the hole, a tongue for contacting the lower surface of the fixed contact is bent and formed at a right angle on the lower edge of the lower half portion of the hole, while the leg of the arc horn is fixed to the fixed contact fixing surface of the case. A groove for inserting the tip of the arc horn is provided, the tip of the leg of the arc horn inserted into the fixed contactor through the hole is clamped by the groove, and the tongue is pressed by the fixed contactor. It has to be fixed Te arcing horn fixing device of a circuit breaker according to claim.