JP4542025B2 - Circuit breaker - Google Patents

Description

  The present invention relates to a circuit breaker provided with an arc extinguishing device, and more particularly to a configuration for increasing the arc extinguishing force of an arc current.

  Prior arts related to the present invention, which are described in patent literatures, are described in, for example, Japanese Patent Application Laid-Open No. 8-252010 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2002-75159 (Patent Document 2). There is something that was done. In JP-A-8-25010, an arc extinguishing aid is applied to the surface of the arc extinguishing grid or both sides of the arc extinguishing grid in order to increase the arc extinguishing force of the arc (arc current) of the air circuit breaker. In Japanese Patent Application Laid-Open No. 2002-75159, an arc extinguishing method in which a strip-like magnetic material is bent in a U-shape in a circuit breaker in order to improve the breaking performance and assembly. A configuration in which a U-shaped insulator is fixed to the outside of the plate is described.

JP-A-8-25010 JP 2002-75159 A

Among the techniques described in Japanese Patent Application Laid-Open No. 8-250010, in the configuration in which the arc extinguishing aid is applied to the surface of the arc extinguishing grid, it is expected that the amount of arc extinguishing gas generated is small and the arc extinguishing aid is consumed quickly. In the configuration in which the arc extinguishing aid is installed on both sides of the arc extinguishing grid, the size of the arc extinguishing device tends to increase. Further, even in the technology described in Japanese Patent Laid-Open No. 2002-75159, the size of the arc extinguishing device is likely to increase. Furthermore, the structure tends to be complicated.
An object of the present invention is to make it possible to shorten the arc extinguishing time in a circuit breaker under the condition that the configuration of the arc extinguishing device inside the circuit breaker is reduced and the configuration is simplified. It is.
An object of the present invention is to solve the above-mentioned problems and to provide a circuit breaker that can be miniaturized and has high breaking performance.

  In order to solve the above-described problems, in the present invention, in the circuit breaker, between the height position of the flat surface portion of the flat grid material and the height position of the fixed contact in the position of both sides of the movable contact. When the arc current is generated between the movable contact and the stationary contact, the ablation member is provided with a pair of ablation members arranged in pairs at the height position of the flat plate and facing the flat part of the flat grid material. Melts and generates arc-extinguishing gas to assist arc extinguishing.

  ADVANTAGE OF THE INVENTION According to this invention, the circuit breaker which can be reduced in size and has high interruption | blocking performance can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
1-3 is explanatory drawing of the Example of this invention. 1 is a cross-sectional configuration diagram of a circuit breaker as an embodiment of the present invention, FIG. 2 is a configuration diagram of a portion composed of an arc extinguishing device and a melting member in the circuit breaker of FIG. 1, and FIG. It is another structural example figure of the part which consists of an arc extinguishing apparatus and a fusion member.

  In FIG. 1, 100 is a circuit breaker as an embodiment of the present invention, 1 is a case, 2 is a handle for manually opening and closing a contact, 3 is an opening / closing mechanism for opening and closing the contact, and 4a is movable. The contact 4b is a movable contact base for supporting the movable contact 4a and displacing the movable contact 4a away from the fixed contact, 5a is a fixed contact, 5b is a fixed contact base for supporting the fixed contact 5a, 6 Is an arc extinguishing device that performs arc extinguishing by attracting an arc current (arc) generated between the separated movable contact 4a and fixed contact 5a by electromagnetic force, and 6a is an arc extinguishing device in the arc extinguishing device 6. A substantially U-shaped flat grid material that forms a magnetic path of magnetic flux generated around by an electric current, 6b is a side plate on which the side surface side of the flat grid material 6a is fixed, and 7 is on both side surfaces of the movable contact 4a. Flat grid 6a is arranged in a pair at a height position between the height position of the plane portion 6a and the height position of the fixed contact 5a, the plane faces the plane portion of the flat grid material 6a, and heat based on the arc current (Hereinafter referred to as “arc heat”), a flat plate-like sputter member that generates arc extinguishing gas, 8 is a power supply side terminal block connected to the fixed contact base 5b side, and 9 is a movable contact base 4b. The load side terminal block 4a ′ (broken line portion) connected to the side is a movable contact when separated from the fixed contact 5a, and the movable contact 4a is connected to the fixed contact 5a. The movable contact base 10 in the separated state (= movable contact 4a ′ state) is generated between the separated movable contact 4a and the fixed contact 5a, that is, between the movable contact 4a ′ and the fixed contact 5a. Arc current, 15 is an arc extinguishing case in which the arc extinguishing device 6 is housed It is. The flat plate-like splicing member 7 is made of an insulating polymer material such as vulcanized fiber, nylon or Teflon (registered trademark of DuPont).

  In the configuration of the above embodiment, when an excessive current flows through the circuit with the movable contact 4a and the fixed contact 5a being closed, the electromagnet is activated in the circuit breaker 100 to release the latch state of the latch mechanism. When the latched state is released, the opening / closing mechanism unit 3 operates to operate the toggle mechanism connected to the movable contact base 4b. The toggle mechanism drives and displaces the movable contact base 4b via a spring and a link mechanism, and separates the movable contact 4a from the fixed contact 5a to be in an open state. Since a voltage is applied between the contacts 4a and 5a in the separated state, an arc current 10 flows. When the arc current 10 flows, the current flowing through the fixed contact base 5b near the fixed contact 5a generates a magnetic field and magnetic flux around it. Due to the interaction between the magnetic field (or magnetic flux) and the arc current 10, an electromagnetic force in the direction of the flat grid material 6 a of the arc extinguishing device 6 is generated with respect to the arc current 10. The electromagnetic force is proportional to the product of the magnetic flux density (or magnetic field strength) at the position and the current value of the arc current 10. The arc column by the arc current 10 receives both the electromagnetic force and the force by which the flat grid material 6 a attracts the magnetic field by the arc current 10, and is moved toward the flat grid material 6 a. In the flat grid material 6a, the voltage of the arc column (arc voltage) raised is increased to interrupt the current. On the other hand, the melting member 7 is melted by the arc heat generated by the arc current 10 to generate arc extinguishing gas. The gas covers the periphery of the arc column by the arc current 10, suppresses the increase of the arc current 10, and assists the arc extinguishing operation by the flat grid material 6a. The earlier the arc column of the arc current 10 is moved toward the flat grid material 6a, the earlier the arc current 10 disappears. The circuit current is interrupted by the disappearance of the arc current.

FIG. 2 is a configuration diagram of a combination portion of the arc extinguishing device 6 and the molten member 7 in the circuit breaker 100 of FIG. (A) is a sectional side view, (b) is a bottom view.
In FIG. 2, 6a _{1 to} 6a ₅ are respectively provided as flat plate grid members that form the flat plate grid material 6a, and 6b _{1 to} 6b ₂ are provided outside the side surfaces of the flat plate grid members 6a _{1 to} 6a ₅ respectively. A side plate member (hereinafter also referred to as a side plate) and 7a constituting the side plate 6b (FIG. 1) are one insulating member (hereinafter also referred to as a molten member) of a pair of insulating members that form the fusion member 7. 7a _{1 to} 7a ₂ are members that form the ablation member 7a (hereinafter also referred to as the ablation member), and 7b is a pair of insulating members that form the ablation member 7. The other insulating member (hereinafter also referred to as a molten member), 11a _{1 to} 11a ₄ are fixing means such as caulking for fixing the flat grid members 6a _{1 to} 6a ₅ to the side plates 6b ₁ and 6b _2. . Although not shown, the ablation member 7b is also formed from _two ablation members (referred to as 7b ₁ and 7b ₂ ) similar to the ablation members 7a ₁ and 7a ₂ in the ablation member 7a. (The ablation members 7b ₁ and 7b ₂ are arranged at substantially the same height as the ablation members 7a ₁ and 7a ₂ respectively). Other reference numerals are the same as those in FIG. Ablation member 7a, 7b also respectively fixed to the side plate _6b 1 _{~6b 2} by suitable fastening means (not shown). That is, the ablation member 7a (7a ₁ , 7a ₂ ) is fixed to the side plate 6b ₁ side, and the ablation member 7b (7b ₁ , 7b ₂ ) is fixed to the side plate 6b ₂ side. As described above, the arc extinguishing device 6 is configured in a state in which the flat grid members 6a _{1 to} 6a ₅ are incorporated between the side plates 6b ₁ and 6b ₂ . Further, in the state where the ablation members 7a and 7b are fixed between the side plates 6b ₁ and 6b ₂ of the arc extinguishing device 6, a unit structure comprising the arc extinguishing device 6 and the ablation members 7a and 7b is provided. It is formed. The unit structure is fixed in the arc extinguishing case portion 15 in the circuit breaker 100. Note that the side plates 6b ₁ and 6b ₂ may be integrally coupled to each other below the fusion members 7a ₂ and 7b ₂ . The ablation members 7a ₁ and 7b ₁ may also have a flat U-shaped configuration that is integrally joined to each other. The same applies to the ablation members 7a ₂ and 7b ₂ .

FIG. 3 is a diagram illustrating another configuration example of a combined portion of the arc extinguishing device and the ablation member. In this example, block-like melted members are formed in a pair at a height position between the height position of the flat portion of the flat grid material 6a and the height position of the fixed contact 5a on both side surfaces of the movable contact 4a. This is a case where the plane is provided so as to face the plane portion of the flat grid member 6a.
In FIG. 3, 7 a ′ is one insulating member (hereinafter also referred to as a molten member) of a pair of insulating members that are arranged in a pair on both sides of the movable contact 4 a to form a molten member. 7b ′ is the other of the pair of insulating members that are arranged in a pair on both side surfaces of the movable contact 4a to form a molten member. Insulating member (hereinafter also referred to as a fusion member), which is also composed of one block-like insulating member. Both the ablation members 7a ′ and 7b ′ are made of an insulating polymer material such as vulcanized fiber, nylon or Teflon (registered trademark of DuPont). 11b ₁ ~11b ₄ is a fixing means such as snap fit to secure the plate-like grid member _6a 1 _{~6a 5} to the side plate _6b 1 _{~6b 2.} Other reference numerals are the same as those in FIG. It is assumed that the ablation member 7b ′ is also disposed at substantially the same height as the ablation member 7a ′ with respect to the Z-axis direction. The block-like molten members 7a ′ and 7b ′ are also fixed to the side plates 6b ₁ and 6b ₂ by appropriate fixing means (not shown), respectively. That is, ablation member 7a 'is fixed to the side plate 6b ₁ side, ablation member 7b' is fixed to the side plate 6b ₂ side. Also in this configuration, the arc extinguishing device 6 is configured in a state where the flat grid members 6a _{1 to} 6a ₅ are incorporated between the side plates 6b ₁ and 6b ₂ . Further, the arc extinguishing device 6 and the ablation members 7a ′ and 7b are fixed in a state where the block-like ablation members 7a ′ and 7b ′ are fixed between the side plates 6b ₁ and 6b ₂ of the arc extinguishing device 6. A unit structure consisting of 'is formed. Note that the side plates 6b ₁ and 6b ₂ may be integrally coupled to each other below the fusion members 7a ′ and 7b ′. Further, the ablation members 7a ′ and 7b ′ are not block-shaped but may be flat-plate-shaped.

According to the above-described embodiment, the circuit breaker 100 can be downsized and have high breaking performance under a simple configuration. In other words, the configuration of the embodiment is a configuration in which a plate-like or block-like molten member is provided on the flat grid member 6a similar to that in the conventional circuit breaker and below (−Z-axis direction). The arc device 6 and the circuit breaker 100 can be simplified in configuration, and can be dealt with even with a small design change. Easy to assemble. Further, since the ablation member can be combined with the arc extinguishing device 6 into a single unit structure, handling during assembly is easy, and the arc breaker case 15 of the circuit breaker 100 can be put into the arc extinguishing case portion 15. Easy to incorporate. In addition, the arc arc extinguishing device 6 having a simple configuration can be easily miniaturized by suppressing an increase in size, and the size of the unit structure formed by combining the arc arc extinguishing device 6 and the molten member can be easily miniaturized. For this reason, the dimension reduction of the circuit breaker 100 whole is also attained. Furthermore, since the arc-extinguishing effect of the flat grid material 6a can be efficiently assisted by the gas generated from the molten member, the arc current between the movable contact 4a and the fixed contact 5a can be reduced in a shorter time. The current interruption performance of the circuit breaker 100 can be improved. The arc extinguishing device can be downsized from the viewpoint of improving the current interruption performance. As a result of trial manufacture, for example, the height dimension (Z-axis direction dimension) of a high-capacity circuit breaker of 50 kVA may be reduced from about 103 × 10 ⁻³ m to about 68 × 10 ⁻³ m. It becomes possible. The height dimension of about 68 × 10 ⁻³ m is substantially the same as the conventional medium capacity type circuit breaker and low capacity type circuit breaker.

  In the above embodiment, the ablation member has a flat plate shape or a block shape. However, the present invention is not limited to this, and the positions of both sides of the movable contact 4a are high and the flat portion of the flat grid material is high. As long as it is arranged in a pair at a height position between the vertical position and the height position of the fixed contact 5a, and the plane is opposed to the plane portion of the flat grid material, The thing of a structure may be sufficient. Moreover, in the said Example, although the ablation member was comprised with the insulating high molecular material, as long as the arc extinguishing gas is generate | occur | produced, you may comprise with other than this.

It is a cross-sectional block diagram of the circuit breaker as an Example of this invention. It is a block diagram of the part which consists of an arc extinguishing apparatus and a fusion member in the circuit breaker of FIG. It is another structural example figure of the part which consists of an arc extinguishing apparatus and a fusion member.

Explanation of symbols

1 ... case,
2 ... handle,
3 ... Opening / closing mechanism,
4a, 4a '... movable contacts,
4b, 4b '... movable contact stand,
5a: fixed contact,
5b ... fixed contact stand,
6 ... Arc extinguishing device,
6a: flat grid material,
6a _{1 to} 6a ₅ ... flat grid member,
6b, 6b _{1 to} 6b ₂ ... side plates,
7, 7a, 7b, 7a ′, 7b ′.
8 ... Power supply side terminal block,
9: Load side terminal block,
10: Arc current,
11a _{1 to} 11a ₄ , 11b _{1 to} 11b ₄ ... Fixing means,
15 ... arc extinguishing case part,
100: Circuit breaker.

Claims (3)

A circuit breaker comprising an arc extinguishing device, wherein a movable contact is separated from a fixed contact to interrupt a circuit overcurrent,
An arc extinguishing member in which a plurality of substantially U-shaped flat grid materials are arranged along the opening and closing movement direction of the movable contact;
It is arranged in a pair at a position on both sides of the movable contact between the height of the flat portion of the flat grid material and the height of the fixed contact. The ablation member opposed to the flat portion of the grid-like grid material;
The circuit is characterized in that when the movable contact is separated from the fixed contact and an arc current is generated between the two contacts, the melting member is melted to generate arc extinguishing gas. Circuit breaker.   The circuit breaker according to claim 1, wherein the ablation member is made of an insulating polymer material. The circuit breaker according to claim 1, wherein the ablation member is fixed to a member to which the arc extinguishing member is fixed.

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