JPS6136054Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention relates to circuits and disconnectors,
In particular, the present invention relates to a circuit breaker characterized in that an operating handle is fixed in the closed position when an overcurrent flows in a state where a fixed contact and a movable contact are welded together.

In conventional circuit breakers, when an overcurrent such as a short-circuit current flows between a fixed contact and a movable contact, an electromagnetic tripping device is activated to separate the movable contact from the fixed contact, and at the same time, the operation handle is removed from the circuit. By returning it to the off position, it indicated that the circuit had been disconnected. However, in this conventional circuit breaker, if the fixed contact and the movable contact are welded together when an overcurrent flows, only the operating handle returns to the circuit OFF position, even though the circuit is not immediately broken. This was extremely dangerous as it would result in incorrect display.

This invention was made in order to eliminate the above-mentioned conventional drawbacks. An embodiment of this invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view showing an embodiment of the circuit breaker and circuit breaker according to this invention. In FIG. 1, a fixed contact 2 is fixed to a base 1, and a fixed contact 2 is fixed to a base 1.
A fixed contact 3 is attached to one end. The movable contact 4 is attached to one end of the movable contact 5 opposite to the fixed contact 3. The shaft 6 is the movable contact 5
The other end of the movable contact 5 is rotatably supported by a frame (not shown). A torsion spring 7, which is a biasing means, is wound around a shaft 6, and has one end fixed to the movable contact 5 and the other end fixed to a frame (not shown), so as to separate the movable contact 5 from the fixed contact 2. Acts in the direction of separation. The holding plate 8 is constructed as shown in FIG.
A movable contact 5 is inserted through the base 1, and slides in the vertical direction along a groove 101 provided in the base 1. The operating handle 9 is used to open and close the fixed contact 3 and the movable contact 4, and is rotatably supported by a frame (not shown) by a shaft 10. One end of the link 11 is rotatably supported by a shaft 12 at the inner end of the operating handle 9. The shaft 13 is attached to the other end of the link 11 and slides vertically within a groove 802 of the holding plate 8, the details of which are shown in FIG. Roller 14 is shaft 1
3 and presses the inclined portion 803 of the presser plate 8, the details of which are shown in FIG. The handle spring 15 is wound around the shaft 10, and has one end fixed to the operating handle 9 and the other end fixed to a frame (not shown), and acts in a direction to close the movable contact 4 to the fixed contact 3. The lever 16 has one end rotatably supported by the shaft 10 and the other end 161
comes into contact with the side surface of the presser plate 8 to lock the roller 14 to the inclined portion 803. The electromagnetic trip device 17 includes a magnetic container 171 containing brake oil, an excitation coil 172 wound around the magnetic container 171, a yoke 173 attached to the magnetic container 171 and forming a magnetic circuit, and a yoke. 173 has a central portion rotatably supported by a shaft 174, and one end portion of which is connected to the magnetic container 17.
1 and a movable iron piece 175 that is attracted to the movable iron piece 175. The torsion spring 18 is wound around a shaft 174 and has one end fixed to the yoke 173 and the other end fixed to the movable iron piece 175, and normally acts in the direction of separating the movable iron piece 175 from the magnetic container 171. . The latch 19 is rotatably supported on the yoke 173 by a shaft 20, and a portion 191 engages with the other end 161 of the lever 16 when the movable contact 4 and the fixed contact 3 are closed. , and always part 1
92 is engaged with the other end 175' of the movable iron piece 175. The torsion spring 21 is wound around the shaft 20, with one end fixed to the yoke 173 and the other end fixed to the latch 19.
The latch 19 is rotated counterclockwise about the shaft 20. The flexible conductor 22 connects the other end of the movable contact 5 and the excitation coil 172.
It connects to one end of the . The terminal plate 23 is fixed to the base 1, and one end thereof is connected to the excitation coil 17.
It is attached to the other end of 2 by brazing.

Next, this operation will be explained. When the operating handle 9 is rotated in the closing direction, that is, counterclockwise around the shaft 10, the shaft 12 is attached to the inner end of the operating handle 9.
The link 11, which is attached at one end by the handle 9, moves together with the operating handle 9, and the shaft 13, which is attached to the other end of the link 11, slides downward. Therefore, the roller 14 moves obliquely downward on the inclined portion 803 of the presser plate 8, and presses the lever 16 counterclockwise about the shaft 10. When the lever 16 is pressed against the roller 14, the other end of the lever 16 engages with the latch 19 and the lever 16 is locked.
The roller 14 presses the presser plate 8 downward in accordance with the movement of the operating handle 9 from the position where the lever 16 stops moving. When the shaft 12 passes a known dead point, the movable contact 4 rapidly approaches the fixed contact 3, and the shaft 12 is stopped by locking into a frame (not shown), and the movable contact 4 is moved as shown in FIG. Contact 4
contacts the fixed contact 3 and the closing operation is completed.

When performing an opening operation from the closed state shown in FIG. 3, the operating handle 9 is rotated clockwise about the shaft 10. The holding plate 8 presses the movable contact 5 until the shaft 12 passes the dead point, and when the shaft 12 passes the dead point, the holding plate 8 is pushed upward by the spring force of the torsion spring 7. The presser plate 8 pushed up in this way is stopped by being stopped by a stopping part (not shown) provided on the base 1. Accordingly, the roller 14 is also pushed upward and returns to the state shown in FIG.

Next, when an overcurrent such as a short circuit current flows through the circuit in the closed state shown in FIG. 3, the excitation coil 172 is excited and one end of the movable iron piece 175 is attracted to the magnetic container 171. This disengages the other end 175' of movable iron 175 from portion 192 of latch 19. Therefore, the latch 19 is a torsion spring 21
As a result, the latch 9 rotates counterclockwise about the shaft 20, and the portion 191 of the latch 9 disengages from the other end of the lever 16. Therefore, as shown in FIG.
moves upward.

Next, the operation when an overcurrent flows and the fixed contact 3 and the movable contact 4 melt will be described. When an overcurrent flows, the electromagnetic tripping device 17 operates, and the engagement between the portion 191 of the latch 19 and the other end 161 of the lever 16 is disengaged. Therefore, the holding plate 8 moves upward and the movable contact 4 is opened and separated. At this time, if the fixed contact 3 and the movable contact 4 are welded together by the arc, the presser plate 8 will no longer move upward. The roller 14 still tries to move upward, but since the shaft 13 comes into contact with the engaging part 802',
I can't raise it any higher. Therefore, the link 11 and the operating handle 9 are maintained in the closed state.

As described above, according to this invention, the engaging portion 80
2' is provided, so even if the contacts are welded when the electromagnetic tripping device operates, the operation handle will not go to the OFF position. Therefore, unlike conventional devices, the operating handle is not in the OFF position even though it is energized due to the welding of the contacts, thereby preventing an electric shock accident.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of the circuit breaker and circuit breaker according to this invention. FIG. 2 is a perspective view showing one embodiment of the presser plate. 3 and 4 are main part diagrams for explaining the operation of this invention. In the figures, the same parts in each figure are given the same reference numerals, 1 is the base, 2 is the fixed contact, 3 is the fixed contact, 4 is the movable contact, 5 is the movable contact, 8 is the presser plate, 801 802 is a through hole, 802 is a groove, 802' is an engaging portion, 803 is an inclined portion, 9 is an operating handle, 1
1 is a link, 13 is a shaft, 14 is a roller, and 17 is an electromagnetic tripping device.

Claims (1)

[Claims for Utility Model Registration] A fixed contact having a fixed contact at one end, a movable contact facing the fixed contact at one end, and receiving force in a direction away from the fixed contact by biasing means. A movable contact, a holding plate that has a hole through which the movable contact is inserted and an inclined part that contacts the roller, and slides up and down in conjunction with the movable contact, and has an on position and an off position, and has an on position and an off position, and has an on position and an off position, a link that is connected at one end to the operating handle; a roller provided at the other end of the link that presses the inclined section when the operating handle is inserted; and a roller and the inclined section that are close to the holding plate. a lever provided to maintain a state of contact with the presser plate and release the abutting state by moving away from the presser plate, thereby eliminating the pressure on the sloped portion by the roller; a state in which the lever is close to the presser plate in the engaged state; In a circuit or disconnector equipped with a latch that holds the latch in place, and an electromagnetic trip device that detects overcurrent and releases the latch, when the roller moves upward, the roller is locked to the holding plate. A circuit switch and disconnector characterized in that an engaging portion is provided on the holding plate so that the holding plate is provided with an engaging portion.