JPH01166435A - Electromagnetic device of circuit breaker - Google Patents

Abstract

PURPOSE:To prevent the variation of the rotation position of a movable iron piece and the variation of a movement sensitivity by providing bends bent at both sides of a gearing hole of the movable iron piece with an adequate curvature, and contacting the round angle parts of the bends to the inner surface of a vertical piece of a yoke. CONSTITUTION:While a gearing projection 5a is provided at the tip of a vertical piece 3b of a yoke 3, the gearing projection 5a is inserted to a gearing hole 5b engraved at one end of a movable iron piece 4, and a restoration spring 7 consisting of a coil spring is furnished between a hook 8a furnished at the tip of the gearing projection 5a and a hook 8b furnished at the free end of the movable iron piece 4, Moreover, bends 6 bent with an adequate curvature at both sides of the gearing hole 5b of the movable iron piece 4 are furnished, and the round angle parts of the bends 6 are contacted to the inner surface of the vertical piece 3b of the yoke 3. Consequently, there occurs no variation of rotation position of the movable iron piece 4 even though there is some floating up of the movable iron piece 4 owing to a vibration or a shock, and its movement sensitivity is not changed.

Description

[Detailed description of the invention] [Technical field 1 The present invention relates to an electromagnetic device for a circuit breaker.

[Background Art 1 Conventionally, as an electromagnetic device for this type of circuit breaker, one end of an iron core around which an excitation coil is wound is connected to a horizontal piece of an L-shaped yoke to form a U-shaped magnetic circuit. -i is rotatably attached to the tip of the vertical piece of the yoke, and the free end of the movable iron piece can be freely engaged with the latch release lever of the circuit breaker switch device. There was one that was made to be able to be freely attracted and was formed by interposing a return spring between the movable iron piece and the yoke.

By the way, in such an electromagnetic device of a circuit breaker,
The pivoting portion of the movable iron piece is an engaging protrusion 5fi provided at the tip of the vertical piece 3b of the yoke 3, as shown in Fig. Pt56.
is formed by inserting it into an engagement hole 5a drilled in one end of the movable iron piece 4, and a hook part 8a provided at the tip of the engagement protrusion 5a and a hook part 8a provided at the free end of the movable iron piece 4. A return spring 7 made of a coil spring is interposed between the hook portion 8b and the hook portion 8b. However, in such a conventional example, since the corner of the engagement hole 5b is pressed against the side surface of the engagement protrusion 5a by the spring force of the return spring 7, the movable iron piece may be damaged by vibration or impact. 4 lifts up, the movable iron piece 4 does not return to its original position and rotates at the lifted position, and the change in the movable position of the movable iron piece changes the sensitivity characteristics (overcurrent detection characteristics) of the electromagnetic device. There was a problem in that it would change.

[Objective of the Invention 1 The present invention has been made in view of the above points, and its purpose is to change the rotational position of the movable iron piece even if the movable iron piece is lifted due to vibration or impact. To provide an electromagnetic device for a circuit breaker, which is free from changes in its sensitive characteristics.

[Disclosure of the Invention 1 (M-Construction)] The present invention connects one end of an iron core around which an excitation coil is wound to a horizontal piece of an L-shaped yoke to form a U-shaped magnetic circuit, and one end of the iron core is connected to a horizontal piece of an L-shaped yoke. The center part of the movable iron piece is rotatably attached to the tip of the vertical piece of the iron core, and the free end can be freely engaged with the latch release lever of the circuit breaker opening/closing device. An electromagnetic circuit breaker with a return spring interposed between the and the yoke. ! At the same time, an engaging protrusion is provided at the tip of the vertical piece of the yoke, and the engaging protrusion is inserted into an engaging hole drilled at one end of the movable iron piece, and the hook part provided at the tip of the engaging protrusion is connected to the engaging protrusion. A return spring made of a coil spring is interposed between the hook part provided at the free end of the movable iron piece, and bent parts bent with an appropriate curvature are provided on both sides of the engagement hole of the movable iron piece. By bringing the rounded corner of the part into contact with the inner surface of the vertical piece of the yoke, even if the movable iron piece is lifted due to vibration or impact,
To provide an electromagnetic device for a circuit breaker in which the rotational position of a movable iron piece does not change and the touching characteristics do not change.

(Embodiment) Figures tJfJ1 to 5 show an embodiment of the present invention, and a circuit breaker incorporating the electromagnetic device according to the present invention is
As shown in FIG. 1, the body 12m and the cover 12b
An opening/closing device equipped with a trip mechanism inside the housing 12 consisting of r! IA and electromagnetic device B are housed, and when an excessive load current flows between the input/output terminals (power supply side, load side terminals) 13a and 13b, electromagnetic device B operates, and the electromagnetic device! ! B
The tip of the movable iron piece 4 presses the latch release lever 14 of the trip mechanism of the switching device A downward to perform a tripping operation and open the switching contact (not shown) inserted in the load circuit. It has become. In addition, the opening/closing device 1
The opening/closing operation of the contact 1 and the release of the trip state are performed by a handle 15.

By the way, in the electromagnetic device B, one end of the iron core 2 around which the excitation coil 1 is wound is coupled to the horizontal piece 3a of the six-shaped yoke 3 to form a U-shaped magnetic circuit. Now, as iron core 2, oil dash pot 8! A device incorporating a delay operation means consisting of a structure is used. That is, the iron core 2 is fixed inside a cylinder filled with oil.
a and a movable iron core 2b are opposed to each other via a coil spring 2c, and when the load current flowing through the excitation coil 1 increases, the movable iron core 2b is drawn toward the fixed iron core 2a (sucked into the excitation coil 1). ), a magnetic attraction force capable of attracting the movable iron piece 4 is generated when a load current exceeding a preset value continues to flow for a certain period of time or more. On the other hand, the movable iron piece 4 is rotatably attached by engaging an engagement hole 5a formed at one end with an engagement protrusion 5b provided at the tip of the vertical piece 3b of the yoke 3, and the free end can be freely engaged with the latch release lever 14 of the trip mechanism of the opening/closing device A,
The center part can be freely adsorbed to the other end of the iron core 2. Also,
The return spring 7 interposed between the movable iron piece 4 and the yoke 3 has a hook part 8a provided at the tip of the engagement protrusion 5a of the movable iron piece 4, and a hook part provided at the tip of the movable iron piece 4. It is formed of a coil spring interposed between the spring 8b and the spring 8b. Further, on both sides of the retaining hole 5a of the movable iron piece 4, bent portions 6 are provided which are bent with an appropriate curvature, and the rounded corners of the bent portions 6 are connected to the vertical piece 3b of the yoke 3.
By abutting against the inner surface of the shaft to form a pivoting support,
The movable iron piece 4 is made to rotate smoothly.

Furthermore, a pair of regulating lips 9 protruding from the housing 12 on both sides of the return spring 7 are brought into contact with the opposite surface of the movable iron piece 4 to the suction surface, thereby preventing the movable iron piece 4 from lifting up. There is. *In addition, in the embodiment, the stepped portion 9a near the opening provided in the housing 12 to expose the vertical piece of the yoke 4 to the terminal block portion is used as a regulating rib, and the lifting of the pivot portion of the movable iron piece 4 is also prevented. It can be prevented.

The operation of the embodiment will be described below. Now, the movable iron piece 4 of the electromagnetic device B is rotatably supported at the tip of the vertical piece 3b of the seeker 3, and a return spring 7 is interposed between the movable iron piece 4 and the yoke 3, and the excitation coil 1, when an overcurrent flows for a certain period of time or more, the movable iron piece 4 is attracted to the iron core 2 against the spring force of the return spring 7, and the opening/closing mechanism A that can freely engage with the free end of the movable iron piece 4 is tripped If11. The tripping operation is performed by pressing the latch release lever 14 of the structure downward.
It opens a switching contact (not shown) inserted into the load circuit. On the other hand, unless an overcurrent flows through the excitation coil 1, the movable iron piece 4 is not attracted to the iron core 2, and is held in the non-operating position by the return spring 7. By the way, when vibrations or shocks are applied to such an electromagnetic device B, the movable iron piece 4 may lift up and the pivot position may shift, but in the present invention, the bent portion of the movable iron piece 4 The rounded corner of 6 abuts against the vertical piece 3b of the yoke 3 to form a rotating pivot portion, and the coefficient of friction between the vertical piece 3b of the yoke 3 and the bent portion 6 is small, so that the return The vertical component of the spring force of the spring 7 causes the movable iron piece 4 to immediately return to its original rotational support position, and unlike the conventional example, the rotational support position of the movable iron piece 4 does not change. The moving characteristics do not change accordingly, and the rounded corners of the bent portions 6 allow normal rotation of the movable iron piece 4 to be performed smoothly, resulting in stable operating characteristics. Furthermore, since the magnetic resistance between the movable iron piece 4 and the yoke 3 can be reduced, the movable iron piece 4
The suction properties of will also be improved.

[Effects of the Invention] As described above, the present invention connects one end of the iron core around which the excitation coil is wound to the horizontal piece of the L-shaped yoke to form a U-shaped magnetic circuit, and one end of the iron core is connected to the horizontal piece of the L-shaped yoke. The center part of the movable iron piece is rotatably attached to the tip of the vertical piece of the iron core, and the free end can be freely engaged with the latch release lever of the circuit breaker opening/closing device. In an electromagnetic device for a circuit breaker, in which a return spring is interposed between the yoke and the yoke, an engaging protrusion is provided at the tip of the vertical piece of the yoke, and an engaging hole is provided in the -ra portion of the movable iron piece. The movable iron piece is inserted through the engagement protrusion, and a return spring made of a coil spring is interposed between the hook part provided at the tip of the engagement protrusion and the hook part provided at the free end of the movable iron piece. By providing bent portions with an appropriate curvature on both sides of the engagement hole, and by bringing the rounded corners of the bent portions into contact with the inner surface of the vertical piece of the yoke, lifting of the movable iron piece due to vibration or impact can be prevented. The rotating position of the movable iron piece does not change even when
M! ,! This has the advantage that it is possible to provide an electromagnetic device for a circuit breaker whose alJ characteristics do not change.

[Brief explanation of the drawing]

! Figure #1 is a sectional view of a circuit breaker using an electromagnetic IN device according to an embodiment of the present invention, Figure 2 is a partially cutaway top view of the same, and Figure 3 is a perspective view of an embodiment of the present invention. FIG. 4 is an exploded perspective view of the same as above, FIG. A is a switchgear, B is an electromagnetic device, 1 is an excitation coil, 2 is an iron core, 3 is a yoke, 3m is a horizontal piece, 3b is a vertical piece, 4 is a movable iron piece, 5a is an engagement projection, 5b is an engagement hole , 6 is a bent portion, 7 is a return spring, and 8'a, 8b are hook portions. Agent Patent Attorney Ishi 1) Chief 7 Figure 4 Figure 5

Claims (1)

[Claims] (1) One end of the iron core around which the excitation coil is wound is connected to the horizontal piece of the L-shaped yoke to form a U-shaped magnetic circuit, and one end is rotatably attached to the tip of the vertical piece of the yoke. The central part of the attached movable iron piece, the free end of which can freely engage the latch release lever of the circuit breaker switchgear, can be freely attracted to the other end of the iron core,
In an electromagnetic device for a circuit breaker in which a return spring is interposed between a movable iron piece and a yoke, an engagement protrusion is provided at the tip of a vertical piece of the yoke, and an engagement hole is bored at one end of the movable iron piece. A return spring made of a coil spring is interposed between the hook provided at the tip of the engagement protrusion and the hook provided at the free end of the movable iron piece. 1. An electromagnetic device for a circuit breaker, characterized in that bent portions bent with appropriate curvature are provided on both sides of an engagement hole of an iron piece, and the rounded corners of the bent portions are brought into contact with the inner surface of a vertical piece of a yoke.