JP4213006B2 - Circuit breaker electromagnetic device - Google Patents

Description

  The present invention relates to an electromagnetic device for a circuit breaker that operates when an excessive current flows in a main circuit due to a short circuit or the like and interrupts the main circuit.

As shown in FIG. 5, the electromagnetic device 31 of the circuit breaker includes a flat fixed electromagnetic piece 32 and a movable electromagnetic piece that is arranged to face the fixed electromagnetic piece 32 and is pivotally supported about a pivot 34. 33 and a torsion spring 35 that urges the movable electromagnetic piece 33 so as to be separated from the fixed electromagnetic piece 32, and a substantially crank-shaped terminal seat 37 having a terminal screw 36 screwed to one end thereof. A substantially L-shaped heater 38 is connected to the other end, the fixed electromagnetic piece 32 is brought into close contact with the side where the terminal seat 37 of the heater 38 is connected, and the bimetal 39 is brought into close contact with the opposite side. And the heater 38 and the bimetal 39 are fixed by caulking, and the fixed electromagnetic piece unit 41 in which the flexible copper wire 40 is connected to the side of the heater 38 on which the bimetal 39 is attached is disposed on the base 44 of the circuit breaker. The pivot of the movable electromagnetic piece 33 The movable electromagnetic piece unit 43 assembled by inserting the ring portion 35a of the torsion spring 35 to 34 is assembled so that the movable electromagnetic piece 33 is opposite to the fixed electromagnetic piece 32 with the heater 38 interposed therebetween. A hook 35 c formed at the end is engaged with the fixed electromagnetic piece 32 and the movable electromagnetic piece 33. One end of the torsion spring 35 extends upward from the pivot 34 to engage the hook 35c with the arm 33d of the movable electromagnetic piece 33, and the other end extends downward from the pivot 34 to fix the hook 35c. It engages with a recess 32a formed in the electromagnetic piece 32 (see, for example, Patent Document 1).
JP-A-9-63452

  In conventional electromagnetic devices, the bimetal does not contact the pivot of the movable electromagnetic piece due to deformation to the side of the movable electromagnetic piece that occurs when the bimetal is caulked to the heater, or bending operation away from the bimetallic heater during overcurrent. In consideration of the position of the movable electromagnetic piece, it is necessary to move the movable electromagnetic piece away from the heater, and the space occupied by the electromagnetic device is increased. Moreover, depending on the storage state of the flexible copper wire, the lower end of the movable electromagnetic piece may come into contact with the flexible copper wire and the operation of the movable electromagnetic piece may be hindered, and a technique is required for assembly. Further, it takes time to engage the torsion spring with the fixed electromagnetic piece and the movable electromagnetic piece.

  According to the first aspect of the present invention, there is provided a terminal seat in which a terminal screw is screwed to one end, a heater connected to the other end of the terminal seat, and a part of the heater. It is attached to a circuit breaker equipped with a bimetal for detecting overcurrent that is connected in close contact and a flexible copper wire that is connected to a heater. Connected to the heater's terminal seat in an electromagnetic device consisting of a movable electromagnetic piece that is arranged and pivotally supported about a pivot, and a torsion spring that biases the movable electromagnetic piece away from the fixed electromagnetic piece A bimetal and a fixed electromagnetic piece are fixed to the opposite side to the formed side, a flexible copper wire is connected, and a movable electromagnetic piece is disposed on the opposite side of the fixed electromagnetic piece with a heater interposed therebetween.

  According to the second aspect of the present invention, in the electromagnetic device for a circuit breaker according to the first aspect, the ring portion is inserted through the pivot so that both ends of the torsion spring are below the pivot, and the movable electromagnetic Fixed electromagnetic piece unit consisting of fixed electromagnetic piece, terminal seat, heater, bimetal and flexible copper wire after moving electromagnetic piece unit consisting of piece, pivot and torsion spring to pivot base on breaker case base Is attached from above the movable electromagnetic piece unit.

  The electromagnetic device of the circuit breaker according to the present invention can reduce the occupied space in the circuit breaker, there is no possibility that the operation of the movable electromagnetic piece is obstructed by the flexible copper wire, and the engagement of the torsion spring There is an effect that anybody can easily assemble it.

  The electromagnetic device fixes the bimetal and the fixed electromagnetic piece on the opposite side to the side where the heater terminal is connected and the vertical part, and connects the flexible copper wire to the horizontal part, and sandwiches the heater with the fixed electromagnetic piece. A movable electromagnetic piece is rotatably disposed on the opposite side at a distance from the vertical portion of the heater.

  An embodiment of an electromagnetic device for a circuit breaker according to the present invention will be described with reference to the accompanying drawings of FIGS.

  The electromagnetic device 1 includes a plate-shaped fixed electromagnetic piece 2, a substantially U-shaped movable electromagnetic piece 3 that is disposed so as to face the fixed electromagnetic piece 2 and pivotally supported, and rotates the movable electromagnetic piece 3. In this case, the pivot 4 is a shaft, and the torsion spring 5 urges the movable electromagnetic piece 3 so as to be separated from the fixed electromagnetic piece 2.

  The circuit breaker in which the electromagnetic device 1 is incorporated has a substantially crank-shaped terminal seat 7 in which a terminal screw 6 is screwed to one end portion, and a vertical portion 8a connected to the other end portion of the terminal seat 7 and a horizontal portion. A substantially L-shaped heater 8 composed of a portion 8 b, a bimetal 9 for detecting an overcurrent connected to the heater 8 in close contact with the heater 8, and a flexible copper wire 10 connected to the heater 8. Yes. The bimetal 9 is bent by receiving heat from the heater 8 at the time of overcurrent, and the tip operates an opening / closing mechanism (not shown) to interrupt the main circuit. The terminal seat 7, the heater 8, and the flexible copper wire 10 are part of the main circuit of the circuit breaker and are formed of a nonmagnetic material such as copper. The fixed electromagnetic piece 2 and the movable electromagnetic piece 3 constituting the electromagnetic device 1 are made of a magnetic material such as iron.

  The heater 8 has a bimetal 9 and a fixed electromagnetic piece 2 crimped and fixed on the opposite side of the side to which the terminal seat 7 is connected and the vertical portion 8a, and a flexible copper wire 10 is welded to the horizontal portion 8b. The fixed electromagnetic piece unit 11 is connected and formed. The fixed electromagnetic piece unit 11 is provided with a zero-phase current transformer 12 for detecting a leakage current so as to penetrate the terminal seat 7.

  The movable electromagnetic piece 3 is formed in a substantially U shape by bending the bent portions 3b on both the left and right sides of the flat plate portion 3a, and a shaft hole 3c is formed in the upper portion of the bent portion 3b. Can be inserted. Further, an arm portion 3d for driving an opening / closing mechanism portion of the circuit breaker extends obliquely upward at the upper end portion of the one bent portion 3b. The torsion spring 5 is formed by a plurality of wound rings 5a, a short arm 5b that extends short from the ring 5a, and a long arm 5d that extends long from the ring 5a and has a hook 5c at the tip. Then, the pivot 4 is inserted into one shaft hole 3c of the movable electromagnetic piece 3 from the outside, the ring portion 5a of the torsion spring 5 is inserted into the tip of the pivot 4 coming out of the shaft hole 3c, and the tip of the pivot 4 is connected to the other. The movable electromagnetic piece unit 13 is formed by being inserted into the shaft hole 3c. Note that both ends of the torsion spring 5 hang down below the pivot 4 on the same side as the bent portion 3 b with respect to the flat plate portion 3 a of the movable electromagnetic piece 3.

  A pair of opposed frames 15 are suspended from the base 14 of the circuit breaker case, and U-shaped grooves 16 are formed in the frames 15 respectively. The pivot 4 of the movable electromagnetic piece unit 13 is fitted into the groove 16 from above and is pivotally attached. Then, the fixed electromagnetic piece unit 11 is disposed from the upper side of the movable electromagnetic piece unit 13 so that the movable electromagnetic piece 3 is opposite to the fixed electromagnetic piece 2 across the heater 8. The movable electromagnetic piece unit 13 is accommodated in a space surrounded by the heater 8, the terminal seat 7, and the zero-phase current transformer 12 of the fixed electromagnetic piece unit 11. When the fixed electromagnetic piece unit 11 is lowered, the hook 5c of the long arm 5d of the torsion spring 5 of the movable electromagnetic piece unit 13 is engaged with the lower end edge of the fixed electromagnetic piece 2, and the short arm 5b of the torsion spring 5 is moved to the movable electromagnetic piece 3. The flat plate part is locked.

  In the electromagnetic device 1 assembled in this manner, the lower part of the movable electromagnetic piece 3 resists the spring force of the torsion spring 5 due to the magnetic field generated around the heater 8 when an excessive current due to a short circuit flows in the main circuit of the circuit breaker. At this time, the arm portion 3d of the movable electromagnetic piece 3 operates the opening / closing mechanism portion so that the opening / closing mechanism portion is driven to shut off the main circuit.

  In this embodiment, the torsion spring has the long arm hook locked to the lower end edge of the fixed electromagnetic piece and the short arm locked to the flat plate portion of the movable electromagnetic piece. If the torsion spring urges the movable electromagnetic piece to be separated from the fixed electromagnetic piece when mounted from above, there is no limitation on the locking position of the torsion spring, and the shape of the members constituting the electromagnetic device The structure and the structure can be changed as appropriate without departing from the spirit of the present invention.

It is a perspective view which shows the electromagnetic device which concerns on this invention. It is a front view which shows a mode that the fixed electromagnetic piece unit which concerns on this invention is attached to a movable electromagnetic piece unit. It is a perspective view which shows the state which attached the electromagnetic device which concerns on this invention to the base. It is a front view which shows a mode that the fixed electromagnetic piece unit which concerns on this invention was attached to the movable electromagnetic piece unit. It is a front view which shows the conventional electromagnetic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic device 2 Fixed electromagnetic piece 3 Movable electromagnetic piece 3a Flat plate part 3b Bending part 3c Shaft hole 3d Arm part 4 Pivot 5 Torsion spring 5a Ring part 5b Short arm 5c Hook 5d Long arm 6 Terminal screw 7 Terminal seat 8 Heater 8a Vertical Part 8b Horizontal part 9 Bimetal 10 Flexible copper wire 11 Fixed electromagnetic piece unit 12 Zero phase current transformer 13 Movable electromagnetic piece unit 14 Base 15 Frame 16 Groove

Claims (2)

  A terminal seat in which a terminal screw is screwed to one end, a heater connected to the other end of the terminal seat, and a bimetal for detecting an overcurrent that is connected in close contact with the heater And a circuit breaker including a flexible copper wire connected to the heater, and is arranged to face the fixed electromagnetic piece and to be fixed to the plate-like fixed electromagnetic piece so as to be rotatable about the pivot axis. In an electromagnetic device comprising a supported movable electromagnetic piece and a torsion spring that biases the movable electromagnetic piece away from the fixed electromagnetic piece, the heater has a side opposite to the side to which the terminal seat is connected. The electromagnetic of a circuit breaker characterized by fixing the bimetal and the fixed electromagnetic piece, connecting the flexible copper wire, and arranging the movable electromagnetic piece on the opposite side of the fixed electromagnetic piece across the heater. apparatus.   A ring portion is inserted and attached to the pivot so that both ends of the torsion spring are below the pivot, and a movable electromagnetic piece unit comprising the movable electromagnetic piece, the pivot, and the torsion spring is connected to the pivot. After attaching to the base of the case, the fixed electromagnetic piece unit composed of the fixed electromagnetic piece, the terminal seat, the heater, the bimetal, and the flexible copper wire is attached from above the movable electromagnetic piece unit. The electromagnetic device for a circuit breaker according to claim 1.

Images