JPH0454650Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to an arc extinguishing device that extinguishes an arc generated when a contact is opened.

[Background Art] Generally, when extinguishing an arc generated when a contact is opened, an arc extinguishing grid device is used in which a plurality of grid plates are spaced apart and arranged substantially in parallel. The arc extinguishing device is comprised of this arc extinguishing grid device and means for guiding the arc generated at the contact to the arc extinguishing grid device. As a means for guiding the arc into the arc extinguishing grid device, as shown in FIG. 7 or FIG. A method is being considered that utilizes Lorentzka due to interaction with arc current. The fixed contact plate 11 provided with the fixed contact 12 has an arc traveling plate 14' extending from the fixed contact 12 to an arc extinguishing grid device (not shown, but disposed in front of the fixed contact 12 in FIGS. 7 and 8). The arc traveling plate 14' is wider than the fixed contact plate 11 at the portion facing the grid plate of the arc extinguishing grid device. By forming the arc travel plate 14' in a T-shape in this manner, the arc extinguishing effect due to heat radiation cooling of the arc, etc. is enhanced. Further, the drive coil 16 has a terminal plate 19 connected to one end.

By the way, since the arc traveling plate 14' is formed in a T-shape, the fixed contact plate 11, the arc traveling plate 14', the drive coil 16, and the terminal plate 19 can all be formed by punching out a single sheet metal. It cannot be formed in one piece. Therefore, in the configuration shown in FIG. 7, the fixed contact plate 11 and the arc traveling plate 14' are formed of one sheet metal, and the fixed contact plate 11 and the drive coil 16, and the drive coil 16 and the terminal plate 19 are It is configured to be brazed or welded. Furthermore, in the configuration shown in FIG.
Although the fixed contact plate 11, drive coil 16, and terminal plate 19 are formed of one sheet metal, as shown in FIG. 9, the arc running plate 14' is a separate piece.
It is caulked and fixed to the fixed contact plate 11. These configurations have a problem of low productivity because the number of parts increases and joining work between the parts is required.

[Purpose of the invention] The present invention was made in view of the above points, and its main purpose is to efficiently extinguish the arc without forming a wide arc travel plate. It is an object of the present invention to provide an arc extinguishing device in which an arc travel plate, a fixed contact plate, a drive coil, and a terminal plate can be integrally formed from one sheet metal.

[Disclosure of the invention] (Example) In the following explanation, the terminal screw 22 in FIG.
The one end provided with is the front end, and both drive coils 16
The direction in which they are connected is defined as the left-right direction, but this does not limit the mounting direction.

As shown in FIGS. 1 to 3, the fixed contact plate 11 is formed into a straight line with both side edges parallel to each other.
A fixed contact 12 is provided on the upper surface of the intermediate portion in the front-rear direction. A stepped portion 13 is formed at a position corresponding to the front end of the fixed contact 12 on the fixed contact plate 11, and the upper surface of the portion in front of the stepped portion 13 and the upper surface of the fixed contact 12 are located on approximately the same plane. It's becoming like that. That is, the arc traveling plate 14 is formed by the portion of the fixed contact plate 11 that extends further forward than the fixed contact 12 . Arc running plate 14
A tongue piece 15 bent diagonally downward is provided at the front end.

Drive coils 16 each having a central axis in the left and right direction and being bent into a downwardly opening U shape are disposed on both the left and right sides of the fixed contact plate 11. Corresponding fixed contact 1
The drive coil 12 is formed such that 2 is located. Further, the central axes of both drive coils 12 are located on the same straight line. The rear end of the drive coil 16 is integrally continuous with the rear end of the fixed contact plate 11.
The front end of the terminal plate 17 is integrally continuous with the terminal plate 17. The front end of the arc travel plate 14 is located further forward than the front end of the drive coil 16.

The terminal plate 17 has a stepped portion 18 at an intermediate portion in the front-rear direction, and the terminal piece 19 at the front end is located higher than the arc introduction piece 20 at the rear end. Arc introduction piece 2
The rear end of the arc introduction piece 20 is continuous with the drive coil 16, and the arc introduction piece 20 is wider in the horizontal width than the fixed contact plate 11. A notch 21 is formed in the center of the rear edge of the arc introduction piece 20, and the tongue piece 15 of the arc travel plate 14 is inserted into this notch 21. Further, as shown in FIG. 3, the tongue piece 15
The upper surface of the front end is located below the upper surface of the arc introducing piece 20. On the other hand, the terminal piece 19 has a terminal screw 22.
are screwed together.

An arc extinguishing grid device 30 is disposed between the drive coil 16 and the stepped portion 18, as shown in FIG. The arc extinguishing grid device 30 includes a plurality of grid plates 31 arranged vertically in parallel and spaced apart from each other.
Each grid plate 31 is made of a conductive material and has a notch 32 formed in the center of its rear edge. Grid plate 31 located at the lowest end
The lower surface faces the upper surface of the arc introducing piece 20.

Fixed contact plate 11, drive coil 16, and terminal plate 17
As shown in FIG. 5, a conductive rectangular sheet metal 25 having a U-shaped cutout groove 23 formed by punching is formed into the above-mentioned shape at the broken line 24 shown in FIG. It is formed into one piece by bending it so that it becomes . That is, it can be processed by simply punching out and bending a single sheet metal 25, resulting in fewer parts and higher productivity.

The arc extinguishing device 1 described above, as shown in FIG.
Used in circuit breakers, etc. That is, the circuit breaker includes a contact device 4 that opens and closes the main electrical circuit formed between the terminals 3 provided at both ends of the housing 2, and an overcurrent detection device 5 that operates when an excessive current flows in the main electrical circuit. , a trip device 6 consisting of a plurality of links, and a handle 7 for opening and closing the contact device 4.
and the arc extinguishing device 1 described above. The trip device 6 is connected to the contact device 4 by operating the handle 7.
When the contact device 4 is closed, a plurality of springs accumulates force in the direction of opening the contact device 4, and when the overcurrent detection device 5 is activated due to excessive current flowing through the main circuit, the accumulated force is released and one end of the movable contact 27 provided with the movable contact 26 is moved upward, thereby rapidly opening the contact device 4. Since the configuration of each device except for the arc extinguishing device 1 can be applied to a conventionally known configuration, a description thereof will be omitted.

(Operation) The operation will be explained below. When the contact device 4 composed of the movable contact 26 and the fixed contact 12 is in a closed state, a magnetic field is generated around the drive coil 16 due to the current flowing through the drive coil 16. Here, when the contact device 4 is opened, an arc 8 is generated between the fixed contact 12 and the movable contact 26, as shown in FIG. 4, and the Lorentz force is the interaction between the arc current and the magnetic field. The arc 8 is urged towards the arc extinguishing grid device 30. When the middle portion of the arc 8 runs along the arc traveling plate 14 and reaches the tongue piece 15 while being stretched, the front end upper surface of the tongue piece 15 is located below the upper surface of the arc introducing piece 20, so that The arc 8 is pulled downward and a part of the arc 8 is connected to the arc introduction piece 20.
will be transferred to. At this stage, the arc 8 is formed between the movable contact 26 and the arc introduction piece 20. That is, since one end of the arc 8 transfers to the arc introducing piece 20 formed wider than the fixed contact plate 11, a high arc extinguishing effect can be achieved by the action of heat dissipation cooling, etc., similar to the conventional T-shaped arc traveling plate. You can get it. Further, in a state where the arc 8 is formed between the movable contact 26 and the arc introduction piece 20, the arc 8 is
The arc 8 is introduced into the interior, the discharge path is divided, and the arc 8 is immediately extinguished by the radiation cooling action.

[Effects of the invention] As described above, the present invention consists of a fixed contact plate in which the fixed contacts that constitute the contact together with the movable contacts are provided on one side and the edges on both sides are formed in a straight line, and the fixed contacts are arranged on both sides of the fixed contact plate. a pair of drive coils which are curved so that one end thereof is connected to one end of the fixed contact plate, the other end is located on the other end side of the fixed contact plate, and protrudes toward one side of the fixed contact plate on which the fixed contact is provided; A fixed contact plate is formed by bending a conductive sheet metal punched into a predetermined shape, and a terminal plate is disposed at the other end of the fixed contact plate through a gap and is continuous with the other end of the drive coil. An arc extinguishing grid device is provided to extinguish the introduced arc by straddling the fixed contact plate and the terminal plate on one side where the fixed contacts are provided, and both drive coils are placed on the side of the fixed contact plate. The central axis is perpendicular to the direction along the edge and the fixed contact is located between both ends of the drive coil, and the fixed contact plate and the surface of the fixed contact are arranged between the fixed contact and the arc extinguishing grid device. The end of the fixed contact plate on the terminal plate side is bent so that the distance from the arc extinguishing grid device is larger than that of the terminal plate, forming a tongue piece. Since the arc travel plate, drive coil, and terminal plate are integrally formed by punching and bending a single sheet metal, it is possible to reduce the number of parts and costs, and improve productivity. There is an advantage to doing so.
In addition, the fixed contact plate and the surface of the fixed contact are set flush between the fixed contact and the arc extinguishing grid device, and the end of the fixed contact plate on the terminal plate side is located at a distance from the arc extinguishing grid device than the terminal plate. Since the tongue piece is bent so that it becomes larger, the arc can be easily transferred from the fixed contact plate to the terminal plate, and it has the same effect as the conventional T-shaped arc traveling plate. It can be played. As a result, the arc is smoothly introduced into the arc extinguishing grid device, and the current limiting effect is enhanced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts showing an embodiment of the present invention;
Figure 2 is a partially cutaway perspective view of the same as above, Figure 3 is a cross-sectional view of essential parts of same as above, Figure 4 is an explanatory diagram of the same as above, Figure 5 is a developed view of important parts of same as above, Figure 6 is same as above. Fig. 7 is a cross-sectional view showing an example of usage, Fig. 7 is a perspective view showing a conventional example, Fig. 8 is a perspective view showing a conventional example.
The figure is a perspective view showing another conventional example, and FIG. 9 is a partially exploded perspective view of the same. 11 is a fixed contact plate, 12 is a fixed contact, 16 is a drive coil, 19 is a terminal plate, and 30 is an arc extinguishing grid device.

Claims (1)

[Scope of utility model registration request] Fixed contacts, which together with the movable contacts constitute a contact, are provided on one side and have straight edges on both sides of the fixed contact plate, and are arranged on both sides of the fixed contact plate, with one end continuous to one end of the fixed contact plate. At the same time, a pair of drive coils, the other end of which is located on the other end of the fixed contact plate, is curved so as to protrude toward one side of the fixed contact plate on which the fixed contact is provided, and the other end of the fixed contact plate is arranged with a gap in between. A terminal plate that is connected to the other end of the drive coil is integrally formed by bending a conductive sheet metal punched into a predetermined shape, and is connected to the fixed contact plate on one side of the fixed contact plate where the fixed contacts are provided. An arc extinguishing grid device is provided to extinguish the introduced arc by straddling the terminal plate. The fixed contact is located between both ends of the drive coil, and the fixed contact plate and the end surface of the fixed contact are set substantially flush between the fixed contact and the arc extinguishing grid device, and the terminal of the fixed contact plate An arc extinguishing device in which a tongue piece is formed by bending the end of the plate so that the distance from the arc extinguishing grid device is greater than that of the terminal plate.