JP5557716B2 - Circuit breaker - Google Patents

Description

  The present invention relates to a mounting structure for a stationary contact of a circuit breaker.

  A circuit breaker is a fixed contact that has a fixed contact integrated with an external connection portion that is a connection portion of an electric wire from an external load, etc., a movable contact that has a movable contact that is in contact with and away from this fixed contact, and an overcurrent It has an open / close mechanism that peels the movable contact from the fixed contact when it flows, and a handle that can switch on and off the electric path of the fixed contact and the movable contact. In this circuit breaker, when an overload or a short circuit occurs, the switching mechanism is activated, the movable contact is peeled off from the fixed contact, and the electric circuit between the movable contact and the fixed contact is interrupted. The handle displays the trip position. As measures against high temperature during energization, contact bounce during short circuit, and rattling of terminals during construction, the fixed contact of the circuit breaker is firmly fixed to the base, and the fixed contact does not move from the base. ing.

  When a short-circuit current flows through such a circuit breaker and the switching mechanism of the circuit breaker is activated to break the circuit, a high temperature is generated when the contact is opened with the fixed contact formed on the fixed contact. Arc (discharge) occurs. In order to maintain the breaking performance, an arc runner and arc extinguishing device are installed near the fixed contact. The generated arc is commutated from the fixed contact to the arc runner, and further commutated into the arc extinguishing device. In the process of this commutation, the distance between the arc spots passing through the arc runner gradually increases, and the arc generated in the meantime is extended. And the extended arc is extinguished by the arc extinguishing plate in the arc extinguishing device.

  As shown in Patent Document 1, the fixed contact is generally fixed by screwing to the base of the circuit breaker. On the other hand, as shown in the cited document 2, the arc runner may be unitized by being fitted to the fixed contact from the viewpoint of assemblability.

Japanese Patent Laid-Open No. 7-85763 Japanese Utility Model Publication No. 61-51648

In the fixed contactor or arc runner fixing method as shown in Patent Document 1 or Patent Document 2, it is necessary to fix the arc contactor to the base by screwing the fixed contactor while fitting the arc runner to the fixed contactor. There was a problem of being bad.
The present invention solves the above problems and provides a holding structure for a fixed contact of a circuit breaker that can attach the fixed contact to a base with good assembling workability.

The invention according to claim 1, which has been made to solve the above problems,
A fixed contact in which a movable contact is separated from and connected to one end side, and an external connection portion connected to the load side is formed on the other end side; and
An arc extinguishing device in which a plurality of arc extinguishing plates are arranged in the arc extinguishing chamber case;
An arc runner disposed in the arc extinguishing chamber case and commutating an arc generated when the movable contact and the stationary contact are separated from each other to the arc extinguishing device;
In the circuit breaker having a base to which the stationary contact, the arc extinguishing device, and the arc runner are attached,
An insertion hole is formed in the fixed contact,
The arc runner is formed with a fixed piece inserted into the insertion hole,
The arc extinguishing device is formed with a pressing portion that presses the arc runner in the base direction,
A mounting groove is formed in the base,
The fixed piece of the arc runner is inserted into the mounting groove of the case in a state of being inserted into the insertion hole of the fixed contact, the fixed contact is press-fitted into the case side by the arc runner, and the arc extinguishing device The arc contactor is attached to the case by the arc runner being pressed toward the base .

The invention according to claim 2 is the invention according to claim 1,
Projections are formed on both sides of the arc runner,
At the lower end of the arc extinguishing chamber case of the arc extinguishing device, a holding notch portion into which the protruding portion enters is formed as a notch,
The arc extinguishing device is mounted in the base in a state in which the protruding portion has entered the holding cutout portion .

The invention according to claim 3 is the invention according to claim 1 or 2,
The cover attached to and attached to the base is formed with a holding portion for receiving the upper part of the arc extinguishing device,
The upper part of the arc extinguishing device is pressed by the cover while the upper part of the arc extinguishing device is received and held by the holding part . Thereby, since the upper part of the arc extinguishing device is received and held by the holding part of the cover and pressed by the cover, the arc extinguishing device does not wobble, and the fixed contact is also firmly fixed to the base. .

According to the present invention, the fixed contact is formed with an insertion hole, the arc runner is formed with a fixed piece that is inserted into the insertion hole, and the arc extinguishing device is formed with a pressing portion that presses the arc runner in the base direction. An attachment groove is formed in the base, and the fixed piece of the arc runner is inserted into the attachment groove of the base in a state where the fixed piece of the arc runner is inserted into the insertion hole of the fixed contact, and the fixed contact is moved to the base side by the arc runner. The stationary contact is attached to the case by being pressed and the arc runner being pressed toward the base by an arc extinguishing device .
As a result, it is not necessary to fix the arc contactor to the base by screwing the fixed contactor while fitting the arc runner to the fixed contact as in the prior art, and the assembly workability is good. Further, since the arc runner is pressed down from above by the arc extinguishing device, the fixed contact pressed against the base by the arc runner is firmly fixed to the base.

It is a whole perspective view of a circuit breaker in the state where a cover was omitted. It is a whole perspective view of a circuit breaker in a state where a cover and a base are omitted. It is a perspective view of a fixed contact, an arc runner, and an arc extinguishing device. It is explanatory drawing which shows the figure currently press-fitted and fixed to the stationary contact by the arc runner. It is explanatory drawing of the state by which the arc-extinguishing apparatus is pressed with the cover. It is sectional drawing of the state in which the arc-extinguishing apparatus is pressed with the cover. It is the perspective view which looked at the cover, the arc-extinguishing device, and the stationary contact from the back side.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the circuit breaker 100 for multiple poles, as shown in FIG. 2, a plurality of movable contacts 11 are attached to a single cross bar 12, and the cross bar 12 is rotatably attached to a mechanical frame 15. The structure is common. When the opening / closing mechanism 16 attached to the mechanical frame 15 is operated, the movable contacts (not shown) of the plurality of movable contacts 11 are simultaneously connected to the fixed contacts 13a (FIG. 3A) of the fixed contacts 13. To be peeled off).

  The casing of the circuit breaker 100 includes a base 1 (shown in FIG. 1) and a cover 2 (shown in FIG. 7) attached to the base 1. In the base 1, a movable contact 11, a cross bar 12, a mechanical frame 15 to which an opening / closing mechanism 16 is attached, a fixed contact 13, an arc runner 17, and an arc extinguishing device 18 are attached. As shown in FIG. 1, a plurality of insertion ports 1 a are formed in parallel on one end side of the base 1. As shown in FIG. 4, a mounting groove 1b is formed in the base 1 on the back side of each insertion port 1a.

  As shown in FIG. 3A, the fixed contact 13 is plate-shaped, and a fixed contact 13a protrudes from one end thereof, and a connection portion of an electric wire from an external load or the like is provided at the other end. An external connection portion 13b is formed. An insertion hole 13 c is formed in the vicinity of the fixed contact 13 a of the fixed contact 13.

  The arc runner 17 commutates an arc generated when the movable contact (not shown) of the movable contact 11 is separated from the fixed contact 13a to an arc extinguishing device 18 described later. As shown in FIG. 3, the arc runner 17 includes a plate-like guide portion 17a and a fixed piece 17b formed by bending from one end of the guide portion 17a. The thickness of the fixed piece 17b is substantially the same as the width of the mounting groove 1b of the base 1. The fixed piece 17b is formed with a hooking portion 17c having a protruding amount that gradually increases from the distal end side to the proximal end side of the fixed piece 17b. Prior to press-fitting the arcrunner 17 into the mounting groove 1b of the base 1, the hooking portion 17c protrudes from the mounting groove 1b. The fixing piece 17b is inserted into the mounting groove 1b, and the hooking portion 17c is bent in the direction of the fixing piece 17b. It is inserted while being pressed and pressed into the base 1. As shown in FIG. 3 and FIG. 5A, projecting portions 17d are formed at both ends of the guide portion 17a. As shown in FIG. 3A, a gap portion 17e is formed in the guide portion 17a.

  As shown in FIG. 4, the external connection portion 13 b is placed on the bottom of the insertion port 1 a of the base 1, and the insertion hole is in a state where the fixed contact 13 a is directed to the back side of the insertion port 1 a of the base 1. A fixed piece 17b of the arc runner 17 is inserted into the 13c, the fixed piece 17b is inserted into the mounting groove 1b, and the fixed contact 13 is attached in a state of being press-fitted into the base 1 from above by the arc runner 17. In this state, the hooking portion 17c of the arc runner 17 is pressed and locked to the mounting groove 1b, so that the arc runner 17 and the fixed contact 13 pressed against the arc runner 17 do not fall off the base 1 and the fixed contact. 13 is firmly attached to the base 1. Of course, a locking recess may be formed in the mounting groove 1b to lock the hooking portion 17c.

  As shown in FIG. 3A, since the gap portion 17e is formed in the guide portion 17a, when the fixing piece 17b of the arc runner 17 is inserted into the mounting groove 1b of the base 1, the gap portion 17e. Since the arc runner 17 can be pressed to the base 1 side by engaging the tool with the base, the workability of attaching the arc runner 17 to the base 1 is improved. If the gap 17e of the arc runner 17 is not formed, there is no place to engage the tool even if the arc runner 17 is pressed against the base 1 side with a tool. Slips from the arc runner 17 and it is difficult to push the arc runner 17 toward the base side.

  In the present invention, the insertion hole 13c is formed in the fixed contact 13, the fixing piece 17b inserted into the insertion hole 13c is formed in the arc runner 17, the mounting groove 1b is formed in the base 1, and the fixing piece 17b of the arc runner 17 is In a state of being inserted through the insertion hole 13c of the fixed contact 13, the fixed contact 13 is press-fitted into the base 1 side by the arc runner 17 by being inserted into the mounting groove 1b of the base 1, and the fixed contact 13 is inserted into the base 1 Decided to attach to. For this reason, unlike the prior art, there is no need to fix the fixed contact 13 to the base 1 by screwing the fixed contact 13 while fitting the arc runner 17 to the fixed contact.

  As shown in FIG. 3, the arc extinguishing device 18 includes an arc extinguishing chamber case 18a and a plurality of arc extinguishing plates 18b. The arc extinguishing chamber case 18a is composed of a plate-like foreign matter entry preventing portion 18c and side walls 18d extending in a direction orthogonal to both ends of the foreign matter entry preventing portion 18c, and has a U-shaped cross section. . In the arc extinguishing chamber case 18a, a plurality of arc extinguishing plates 18b cut out in a substantially V shape are arranged in the vertical direction, and both ends of the arc extinguishing plates 18b are fixed by side walls 18d. The substantially V-shaped cutout portions of the plurality of arc extinguishing plates 18 b serve as a moving path of a movable contact (not shown) of the movable contact 11. The arc extinguishing chamber case 18a is made of a polymer material (for example, polyamide) that discharges arc extinguishing gas from the surface by heating. For this reason, when an arc is generated, the arc extinguishing plate 18b is pyrolyzed by arc heat to generate arc extinguishing gas, and the arc is extinguished. As shown in FIGS. 1 and 2, a gas exhaust port 18e is formed in the foreign matter intrusion preventing portion 18c, and arc gas is exhausted from the gas exhaust port 18e. As shown in FIGS. 3 and 5, a holding notch 18 f is formed at the lower end of the side wall 18 d. The arc extinguishing chamber case 18a of the arc extinguishing device 18 presses the arc runner 17 that is press-fitted and fixed to the base 1 and presses the fixed contact 13 against the base 1. As a preferable form, the arc runner is inserted into the holding notch 18f. 17 projecting part 17d enters, and holding cutout part 18f becomes a pressing part of arc runner 17, and not only arc runner 17 but also arc extinguishing device 18 presses stationary contact 13 against base 1 and can be attached more firmly. It is.

  In the present embodiment, the cover 2 is formed with a holding portion 2a in which the upper part of the arc extinguishing device 18 is received. As shown in FIG. 5, the arc extinguishing device 18 is disposed above the fixed contact 13 a with the guide portion 17 a of the arc runner 17 entering the arc extinguishing chamber case 18 a. In this embodiment, the projecting portion 17d of the arc runner 17 enters the holding cutout portion 18f of the arc extinguishing device 18, and the upper portion of the arc extinguishing device 18 is received and held by the holding portion 2a of the cover 2, and in this state The upper part of the arc extinguishing device 18 is pressed by the cover 2, and the arc runner 17 is further pressed by the arc extinguishing device 18 from the upper side to the lower side, and the cover 2 is screwed with being attached to the base 1. For this reason, the fixed contact 13 pressed against the base 1 by the arc runner 17 is firmly fixed to the base 1. Thus, in this embodiment, since the upper part of the arc-extinguishing device 18 is received and held by the holding part 2a of the cover 2, the arc-extinguishing device 18 does not wobble, and therefore the fixed contact 13 is also firmly formed on the base. 1 is fixed. Further, since the arc extinguishing device 18 is formed with a holding cutout portion 18f into which the projecting portion 17d of the arc runner 17 enters, the positioning operation in the base 1 of the arc extinguishing device 18 becomes easier as compared with the conventional one. Yes. As shown in FIG. 6, the holding portion 2 a of the cover 2 is formed with a fall prevention protrusion 2 b that enters from the upper side inside the foreign matter intrusion prevention portion 18 c of the arc extinguishing device 18. The arc extinguishing device 18 is prevented from falling to the mechanical frame 15 side.

  Although the present invention has been described above in connection with the most practical and preferred embodiments at the present time, the present invention is not limited to the embodiments disclosed herein. However, it can be changed as appropriate without departing from the spirit or concept of the invention that can be read from the claims and the entire specification, and the holding structure of the stationary contact of the circuit breaker accompanying such a change is also included in the technical scope. Must be understood as being.

DESCRIPTION OF SYMBOLS 1 Base 1a Insertion port 1b Mounting groove 2 Cover 2a Holding | maintenance part 2b Fall prevention protrusion 11 Movable contact 12 Crossbar 13 Fixed contact 13a Fixed contact 13b External connection part 13c Insertion hole 15 Mechanical frame 16 Opening and closing mechanism 17 Arc runner 17a Guide part 17b Fixed piece 17c Hooking part 17d Protruding part 17e Air gap part 18 Arc-extinguishing device 18a Arc-extinguishing chamber case 18b Arc-extinguishing plate 18c Foreign matter intrusion prevention part 18d Side wall 18e Gas exhaust port 18f Holding notch part 100 Circuit breaker

Claims (3)

A fixed contact in which a movable contact is separated on one end side and an external connection portion connected to an external load is formed on the other end side; and
An arc extinguishing device in which a plurality of arc extinguishing plates are arranged in the arc extinguishing chamber case;
An arc runner disposed in the arc extinguishing chamber case and commutating an arc generated when the movable contact and the fixed contact are separated from each other to the arc extinguishing device;
In the circuit breaker having a base to which the stationary contact, the arc extinguishing device, and the arc runner are attached,
An insertion hole is formed in the fixed contact,
The arc runner is formed with a fixed piece inserted into the insertion hole,
The arc extinguishing device is formed with a pressing portion that presses the arc runner in the base direction,
A mounting groove is formed in the base,
The fixed piece of the arc runner is inserted into the mounting groove of the base in a state of being inserted through the insertion hole of the fixed contact, the fixed contact is press-fitted into the base side by the arc runner, and the arc extinguishing device The circuit breaker is characterized in that the arc contactor is attached to the base by pressing the arc runner toward the base . Projections are formed on both sides of the arc runner,
At the lower end of the arc extinguishing chamber case of the arc extinguishing device, a holding notch portion into which the protruding portion enters is formed as a notch,
2. The circuit breaker according to claim 1 , wherein the arc extinguishing device is mounted in the base in a state in which the protruding portion enters the holding cutout portion . The cover attached to and attached to the base is formed with a holding portion for receiving the upper part of the arc extinguishing device,
The upper part of the arc-extinguishing device is pressed by the cover while the upper part of the arc-extinguishing device is received and held by the holding part . Circuit breaker.

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