JP3097355B2 - Circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker such as a circuit breaker or an earth leakage breaker, and more particularly to a circuit breaker having no overcurrent tripping function.

[0002]

2. Description of the Related Art A circuit breaker such as a circuit breaker for wiring usually has an overcurrent tripping function. However, apart from such a circuit breaker, there is no overcurrent tripping function. A circuit breaker (non-auto switch) having only an electric circuit opening / closing function may be additionally provided. In that case, if such a circuit breaker is manufactured with a different structure, the cost increases,
It is configured by removing the overcurrent tripping mechanism from a normal circuit breaker. FIG. 5 shows an ON state of a normal circuit breaker having an overcurrent tripping function. The current is supplied from a fixed contact 1 integrated with a power supply side terminal to a movable contact 2, a connection conductor 3, and an overcurrent trip. Via the device 4, it flows to the conductor 5 integrated with the load-side terminal. When the operating handle 6 is tilted rightward in the drawing from the ON state shown in the figure, the opening / closing mechanism 7 is operated, and the holder 9 connected to the toggle link 8 is rotated clockwise, and the support shaft 1 is moved to the holder 9.
The movable contact 2 held through the opening 0 is separated.

When the current is in an overcurrent state, the opening / closing mechanism 7 is operated by the action of the overcurrent trip device 4, and the movable contact 2 is separated. In this case, when a large current such as a short-circuit current flows, the movable contact 1 is rapidly opened by the action of the current limiting mechanism 11 described below prior to the rotation of the holder 9 by the opening / closing mechanism 7. That is, the current limiting pin 12 is fixed to the movable contact 2 in the vicinity of the support shaft 10 serving as a rotation fulcrum so as to protrude on both sides, while the holder has a current limiting latch 13 formed of a V-shaped piece. And is rotatably supported by a pin 14. The current limiting latch 13 is connected to the holder 9.
Are pressed against both ends of the current limiting pin 12 by a current limiting spring 15 composed of a compression coil spring inserted between them.

Here, in the on / off state of the circuit breaker,
In the current limiting latch 13, the lower surface of the bent portion of the figure contacts the current limiting pin 12, and the force of the current limiting spring 15 acting on the current limiting pin 12 via the current limiting latch 13 is reduced by the movable contact. The armature 2 is supported counterclockwise in FIG.
It acts to bias toward. The current limiting spring 15 also serves as a contact spring for the movable contact 2,
In the illustrated ON state, the movable contact 2 is pressed against the fixed contact 1 to apply a required contact pressure between the contacts. In this state, the movable contact 2 is at a position slightly receded clockwise due to the reaction force from the fixed contact 1, and a gap is formed between the movable contact 2 and the stopper of the holder 9 so as to form a so-called wipe.

Now, when a large current passes through the circuit breaker,
The movable contact 2 receives a large electromagnetic repulsion between the movable contact 2 and the fixed contact 1 by currents flowing in opposite directions as indicated by arrows, and pushes the current limiting latch 13 with the current limiting pin 12 to support the shaft. It is driven clockwise in the figure with 10 as a fulcrum. Then, when the current limiting pin 12 gets over the bent portion of the current limiting latch 13 and comes into contact with the upper surface thereof,
Until then, the force of the current limiting spring 15 urged the movable contact 2 in the counterclockwise direction is reversed in the clockwise direction.
Is further accelerated by this force and separates clockwise. Thereby, the so-called current limiting interruption is completed in a short time. By the way, the circuit breaker shown in FIG. 5 is a normal one having the above-mentioned overcurrent tripping function. To use this to constitute a non-auto switch, the overcurrent tripping device 4 is removed. At the same time, the current limiting mechanism 11 is locked so as not to operate.

[0006]

In such a case, the conventional method is shown in FIG.
As shown in FIG.
6 had been inserted. The stopper rod 16 is a movable contact 2
When trying to rotate while pushing back the current limiting latch 13 with the electromagnetic repulsion force, the current limiting pin 12 hits the current limiting latch 13 before climbing over the bent portion of the current limiting latch 13 to limit the rotation, It serves to prevent further movement of the movable contact 2. However, in order to lock the current limiting mechanism 11 having such a configuration, the stopper rod 16 must be inserted in the process of assembling the current limiting mechanism 11 to the holder 9. Therefore, it is necessary to assemble parts (hereinafter, referred to as holder assembly) of this portion separately from a normal circuit breaker in which the stopper bar 16 is not inserted, and since the presence or absence of the stopper bar 16 cannot be seen from the outside, the assembling process is not performed. The management was enormous and the risk of confusing them was high. SUMMARY OF THE INVENTION It is an object of the present invention to provide a circuit breaker in which management of assembly is facilitated by devising a configuration for locking a current limiting mechanism.

[0007]

In order to achieve the above object, according to the present invention, a stopper pin for restricting the rotation of a current limiting latch is inserted into a holder from its side and mounted.

[0008]

The stopper pin for restricting the rotation of the current limiting latch is inserted into the holder holding the movable contact from the side face thereof and mounted, so that the stopper pin can be mounted in the final step of the holder assembly. Become. Therefore, after a normal holder assembly with an overcurrent tripping function is performed, a stopper pin may be inserted as needed for a device that locks the current limiting mechanism, and there is no need to divide the assembly work.
Also, since the presence or absence of the stopper pin can be visually checked from the outside,
No mishandling occurs.

[0009]

1 to 3 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a holder assembling part, FIG. 2 is a rear view thereof, and FIG. It is a principal part side view. The holder assembly shown is the stopper bar 1 in FIG.
The structure is substantially the same as that of the conventional example except that a stopper pin 17 is mounted in place of the stopper 6. The movable contact 2 made of a flat conductor is supported on a hollow holder 9 made of an insulating material. A current limiting pin 12 fixed to the holder 9 near a rotation fulcrum (support shaft 10) of the movable contact and a pin 14 at one end allow the holder 9 to rotate freely. A current limiting latch 13 comprised of a supported square-shaped strip;
A current limiting mechanism 11 including a current limiting spring 15 for pressing the current limiting latch 13 against the current limiting pin 12 is incorporated. The operation of the current limiting mechanism 11 is the same as that described in the conventional example.

As shown in FIG. 2, the connecting conductor 3 is slidably in contact with the movable contact 2 with the movable contact 2 being sandwiched from both sides, and is inserted into both ends of the support shaft 10 with the holder 9. The movable contact 1 is pressed against the side surface by a pair of left and right contact springs 18 composed of compression springs. Both ends of the support shaft 10 are supported by a washer-shaped bearing plate 19 fixed by being fitted into the holder 9. Here, a stopper pin 17 for restricting the rotation of the current limiting latch 13 is mounted on the holder 9 by press-fitting from the side thereof. The stopper pin 17 plays the same role as the stopper rod 16 in the conventional example, and as shown in FIG. 3, the movable contact 2 receives the electromagnetic repulsive force and turns around the support shaft 10 in the counterclockwise direction in FIG. When moving, the current limiting latch 13 which is pushed away by the current limiting pin 12 and tries to rotate in the counterclockwise direction in the drawing with the pin 14 as a fulcrum is indicated by a two-dot chain line before the current limiting pin 12 gets over the bent portion. At the position indicated by, it hits the current limiting latch 13 and prevents further rotation of the movable contact 2.

The stopper pin 17 in the above embodiment is
It can be attached to the holder 9 in the final step of the assembly operation of the holder assembly portion shown in FIGS. Therefore, if a normal product excluding the stopper pin 17 from the illustrated holder assembly is stocked, a non-auto switch for which the current limiting mechanism is locked by obtaining the stopper pin 17 as necessary is obtained. Therefore, there is no need to divide the assembly work depending on the presence or absence of the stopper pin 17. Stopper pin 1
Since it can be seen at a glance from the outside whether or not 7 is mounted, there is no danger of confusing them.

[0012]

According to the present invention, in a circuit breaker having no overcurrent tripping function, a stopper pin for restricting the rotation of the current limiting latch is inserted into the holder from the side thereof and mounted. It is not necessary to distinguish the holder assembly depending on the necessity of locking the flow mechanism, and since the presence or absence of the stopper pin can be easily confirmed from the outside, the parts management becomes extremely easy, and the danger of confusing the parts is eliminated.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a holder assembly part of a circuit breaker according to an embodiment of the present invention.

FIG. 2 is a rear view of FIG.

FIG. 3 is a main part side view for explaining an operation of a stopper pin in FIG. 1;

FIG. 4 is a longitudinal sectional view of a holder assembly part of a circuit breaker showing a conventional example.

FIG. 5 is a vertical sectional view of a main part showing a general configuration of a circuit breaker.

[Explanation of symbols]

 2 Movable contact 3 Connection conductor 9 Holder 10 Support shaft 11 Current limiting mechanism 12 Current limiting pin 13 Current limiting latch 14 Pin 15 Current limiting spring 17 Stopper pin 18 Contact spring

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01H 73/02

Claims (1)

(57) [Claims] 1. A current limiting pin fixed to a vicinity of a rotation fulcrum of a movable contact rotatably held by an insulator holder, and a rectangular piece rotatably supported at one end by the holder. In a circuit breaker provided with a current limiting mechanism comprising a current limiting latch and a current limiting spring for pressing the current limiting latch against the current limiting pin, a stopper pin for limiting rotation of the current limiting latch is provided on a side surface of the holder. Circuit breaker characterized by being inserted and mounted from above.