JP2001068009A - Electromagnetic tripping device of circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic tripping device of a circuit breaker of a structure for which a movable iron core can easily be pivoted on a support member. SOLUTION: An electromagnetic tripping device is structured that a shaft 21a is provided protrusively from each of a pair of support parts 24a and 24b formed on both sides of the central part substantially of a movable iron core 20, and a groove 12 to cause insertion of the shaft 21a is formed in that part of each of a pair of supporting parts 11 of a support member 10, which is located on the side opposite the pulling direction of a return spring 1, and thereby the core 20 can be journaled easily to the support member 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic trip of a circuit breaker, in which a movable core is attracted by an electromagnetic force generated on an attraction surface of a fixed iron core, and a tripping member is driven by the attraction of the movable core to cut off. It concerns the device.

[0002]

2. Description of the Related Art FIG. 8 shows a main part of a conventional electromagnetic trip device of a circuit breaker (Japanese Patent Laid-Open No. 4-280027).
Reference). A support member 40 is attached to a fixed core (not shown), and the movable core 50 is rotatably supported by the support member 40. Bearing holes 41 are provided on both sides of the support member 40.
a and a bearing groove 41 b are formed, and one of a pair of rotating shafts 51, 51 formed in the movable iron core 50 is
a, the other rotating shaft 51 is supported by the bearing groove 41b, and a return spring (not shown) is suspended between the movable core 50 and the support member 40, so that the movable core 50 is supported by the support member. It is prevented from deviating from 40.

[0003]

However, in the above-mentioned conventional example, since one of the two bearings formed in the support member 40 is the bearing hole 41a, the pair of rotating shafts 51 are provided.
Is difficult to penetrate, and it is difficult to pivot the movable iron core 50 to the support member 40.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an electromagnetic trip device for a circuit breaker that facilitates pivotal support of a movable iron core to a support member. .

[0005]

In order to achieve the above object, an object of the present invention is to provide a circuit breaker having a pair of attracting members which generate an electromagnetic force by energizing the conductive unit. A substantially U-shaped fixed core having a front surface and a pair of support portions protruding in the same direction as a pair of suction surfaces of the fixed core and disposed on the back side of the fixed core. And a movable core whose one end side is opposed to each suction surface of the fixed core from the substantially central part, and which is supported by the other end side of the movable core. A return spring that is mounted between the members and biases one end of the movable core away from each suction surface of the fixed core, and attracts the movable core by electromagnetic force generated on the suction surface of the fixed core, An electromagnetic trip device for a circuit breaker that drives and trips a tripping member by suction of a movable iron core In addition to providing shafts protruding from both sides of the substantially central portion of the movable iron core, in each support portion of the support member, a cut groove for inserting the shaft into a portion opposite to the pulling direction of the return spring is provided, The notch allows the movable iron core to be easily supported on the support member, and the provision of the shaft on the movable iron core prevents the shaft from falling off after the movable iron core is attached to the support member.

According to a second aspect of the present invention, in the first aspect of the present invention, the shaft is formed integrally from both sides of the movable iron core. By integrally forming the movable iron core and the shaft, the shaft is formed as a separate part. There is no need to configure, the number of parts can be reduced, and the manufacturing cost can be reduced.

According to a third aspect of the present invention, in the second aspect of the present invention, the shaft is formed by being stamped from both sides of the movable core, and the shaft can be easily formed by driving both sides of the movable core. it can.

[0008] The invention of claim 4 is the first to third aspects of the present invention.
Wherein the fixed core is attached to the inner surface side of the support member, and the support portion of the support member is projected forward from the suction surface of the fixed core, and the fixed core is attached to the support member. In addition, since the movable iron core is attached to the support member via a return spring, the entire device can be made into a block, and the work of housing the circuit breaker can be easily performed. By projecting to the front side from the adsorption surface of the fixed core, one end side can be formed into a substantially linear shape from the shaft support position of the movable core, and it can be used because it does not need to be bent specially. An iron core can be easily manufactured.

The invention according to claim 5 is the invention according to claims 1 to 4.
In the invention of the above, one end side of the movable iron core is substantially opposed to each suction surface of the fixed iron core, and one end side of the movable iron core abuts by the biasing force of the return spring,
The support member is formed with a pair of movement preventing pieces that position one end of the movable core between each of the suction surfaces of the fixed iron core, and one end of the movable iron core is brought into contact with the movement preventing piece in a predetermined range. The above rotation is prevented, and as a result, a fixed distance is maintained between the fixed iron core and one end of the movable iron core. The removal characteristics can be stabilized, and the provision of the movement preventing piece on the support member eliminates the need for a separate member for stopping the rotation of the movable iron core, thereby reducing the number of components.

[0010] The invention of claim 6 is the first to fifth aspects of the present invention.
In the invention of the present invention, the mounting position of the return spring of each of the support member and the movable iron core is shifted in the height direction and the front-rear direction with respect to each other. The distance between the support member and the movable iron core in the front-rear direction can be reduced while maintaining the distance where the same load is applied as when not displaced, and the size can be reduced.

[0011] The invention of claim 7 is the first to sixth aspects of the present invention.
In the invention of the above, the conductive part and the heat generated by the overcurrent flowing through the conductive part displace to a position closer to the fixed core than a position where the movable core is supported between the fixed core and the movable core, and the circuit breaker is pulled. A thermal element that drives and disconnects the detaching member is provided, so that there is no need to dispose a conductive part and a thermal element outside the fixed iron core and the movable iron core, thereby achieving compactness. be able to.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) As shown in FIGS. 1 to 3, an electromagnetic trip device according to this embodiment includes a conductive path 4 serving as a current flow path of a circuit breaker; The bimetal 3 is a thermodynamic element that is displaced by heat generated when an overload current flows through the circuit breaker and drives and trips a tripping member 30 (see FIG. 4) of the circuit breaker. A substantially U-shaped fixed iron core 2 having a pair of suction surfaces 2a, 2a generating a force on its front surface, a substantially U-shaped support member 10 disposed on the back side of the fixed iron core 2, and a substantially central portion. Has a movable iron core 20 supported on both sides by a support member 10, and two return springs 1, 1 mounted between the movable iron core 20 and the support member 10.

As shown in FIG. 1, the support member 10 is
6 are formed in a substantially U-shape by projecting the support portions 11 and 11 from both sides. On one side of the main portion 16 where the support portion 11 is not formed, an insertion portion 18 that is inserted into and fixed to the housing of the circuit breaker is formed.
A spring mounting groove 17 for mounting the return spring 1 is formed at a portion near the side opposite to the insertion portion 18, and another member is provided at a substantially central portion of the main portion 16 with two screws 5. ,
5 are provided with two screw holes 16b, 16b. A pair of supporting portions 11, 11 are formed at their tip portions near the spring mounting groove 17 with incisions 12, each of which is open on the side opposite to the main portion 16, and furthermore, a movement preventing piece 13.
Are formed substantially parallel to the main portion 16.

The fixed iron core 2 is formed in a substantially U-shape with a pair of suction surfaces 2a, 2a on the front surface of which a magnetic force is generated by energizing the conductive path 4, and is supported by two screws 5,5. 2 at the center so that it can be attached to the main part 16 of FIG.
Screw insertion holes 2b, 2b are provided.

The movable iron core 20 has a pair of abutting portions 27, 27 protruding from portions near the bottom side of the both sides, a plate portion 23 formed in a substantially rectangular shape, and a bottom portion on both sides of the plate portion 23. A pair of support parts 24a, 24b protruding from the part near the side opposite to the front side to the front side;
4b. A pair of bearings 2
4a and 24b each have a spring mounting hole 26 and a shaft rod 2.
1 is formed, and the shaft 21 is inserted through the pair of bearing holes 28, 28, and the bearing portion 24 is formed.
By supporting the shaft bar 21 such that both ends of the shaft bar 21 protrude from the shaft portions 21a and 24b, shafts 21a projecting to both sides are formed on each of the support portions 24a and 24b. The one support portion 24a is substantially columnar and formed substantially parallel to the flat plate portion 23, and has an L-shaped portion 2 bent forward to the front end.
5 are formed.

The conductive path 4 is formed in a substantially L-shape, and a screw hole 4a is provided on a bottom surface thereof for attaching to a connection plate 31 of a circuit breaker (see FIG. 4). Two screw insertion holes 4b, 4b for attaching to the main part 16 of the support member 10 with the screws 5, 5 are provided. The bimetal 3 is formed in a substantially rectangular plate shape, and a diagonally bent portion at the tip thereof has a shape as shown in FIG.
A screw hole 3a to which the adjusting screw 6 is attached is provided, and screw insertion holes 3b, 3b for attaching the bimetal 3 to the support member 10 by two screws 5, 5 are provided at the other end side.

Next, an assembling procedure of this embodiment will be described.

As shown in FIG. 1, the main part 1 of the support member 10
6, the fixed iron core 2, the conductive path 4, and the bimetal 3 are arranged in this order from the front side, and two screws 5, 5 are screwed into the screw insertion holes 3 b, 3 b of the bimetal 3, the screw insertion holes 4 b, 4 b of the conductive path 4, The screws are inserted through the screw insertion holes 2 b, 2 b of the fixed iron core 2 from the front side and fastened to the screw holes 16 b, 16 b of the main part 16, and these members are attached to the support member 10. At this time, as shown in FIG. 2 or FIG.
Reference numerals 3 and 13 are arranged so as to substantially oppose a pair of adsorption surfaces 2a of the fixed iron core 2, respectively. Next, the movable iron core 20
Is supported on each support portion 11 of the support member 10, and at this time, a pair of abutting portions 27 of the flat plate portion 23 are respectively disposed between the suction surface 2 a and the movement preventing piece 13, and thereafter, a pair of A pair of shafts 21a, 21a are respectively moved substantially in parallel from the front side and inserted through the cut grooves 12, 12 provided in the support portions 11, 11 at a time, and the movable iron core 20 is pivotally supported by the support member 10. Finally, as shown in FIG. 3, the two return springs 1 and 1 are respectively connected to a pair of spring mounting grooves 17 of the support member 10.
The present embodiment is assembled by hanging the pair of spring mounting grooves 17 in the spring mounting holes 26, 26 located obliquely above in the figure.
The movable iron core 20, which is rotatably supported by the pair of supporting portions 11, 11 a around a fulcrum and is urged by the return spring 1 in a normal state, rotates clockwise in FIG.
7 stops at a position where it contacts the movement preventing piece 13.

The electromagnetic trip device of the present embodiment is shown in FIG.
As shown in the figure, the circuit breaker 35 is housed in the housing 36 at substantially the center. Since the configuration and operation of such a circuit breaker 35 are conventionally well-known, illustration and detailed description are omitted.

As shown in FIG. 4, the electromagnetic tripping device is configured such that the movable iron core 20 and the bimetal 3 are connected to the tripping member 30, which locks the opening / closing mechanism of the circuit breaker 35. The fixing portion 18 is fixed to the housing 36 of the circuit breaker 35 and is housed in the housing 36 of the circuit breaker 35, and the connection plate 31 electrically connected to a movable contact (not shown) has a bottom surface of the conductive path 4. Are superimposed and fastened with screws 33, and the distal end of the conductive path 4 is connected to the terminal plate 32 on the load side. In such a circuit breaker 35, when an overcurrent flows through the conductive path 4 due to, for example, a short-circuit of a load, the pair of suction surfaces 2a, 2a of the fixed core 2 and the flat plate portion 2 of the movable core 20 are formed.
3, the flat plate portion 23 is attracted to the pair of attraction surfaces 2a, 2a, and the movable iron core 20 resists the urging force of the two return springs 1, 1 as shown in FIG. Rotate clockwise. At this time, the distal end of the L-shaped portion 25 of the movable iron core 20 pushes the tripping member 30, and as a result, the opening / closing mechanism is unlocked and the movable contact (not shown) is opened to cut off the current. Then, since the current to the conductive path 4 is cut off, the electromagnetic attraction of the fixed iron core 2 disappears, and the movable iron core 20 is urged by the two return springs 1 and 1 to rotate clockwise in FIG. Then, it stops again at the position where the contact portion 27 of the flat plate portion 23 contacts the movement preventing piece 13 of the support member 10. When an overload current several times to several tens times the rated current flows through the conductive path 4, the bimetal 3 is bent and displaced toward the front side due to Joule heat generated in the conductive path 4, and is mounted on the upper part of the bimetal 3. The tripping member 30 is rotated via the adjusting screw 6 and the movable contact (not shown) is similarly opened to cut off the current.
At this time, the projecting amount of the adjusting screw 6 is adjusted so that the trip member 30 can be pressed and rotated from the displacement position of the bimetal 3 when a predetermined overload current flows through the conductive path 4. I have.

As described above, in this embodiment, the pair of cut grooves 1 formed in the support portions 11 of the support member 10 are formed.
Since the pair of shafts 21a provided on the movable core 20 can be respectively inserted into the movable cores 2 and 12 at one time, there is no need to support the pair of rotating shafts one by one as in the conventional example, and the movable core 20 is supported. The member 10 can be easily pivoted. In addition, by providing the shaft 21 a on the movable core 20, the shaft 2 after the movable core 20 is attached to the support member 10.
1a can be prevented from falling off.

Further, the movable iron core 20 includes a pair of abutting portions 2.
Since the rotation of the fixed iron core 2 and the flat plate portion 23 is maintained at a fixed distance by preventing the rotation of the fixed iron core 2 and the flat plate portion 23, the rotation of the fixed iron core 2 and the flat plate portion 23 is maintained. The tripping characteristics can be stabilized by keeping the electromagnetic attraction force constant during this period. Moreover, since the movement preventing piece 13 is formed integrally with the support member 10, a separate member for preventing the rotation of the movable core 20 is not required, and the number of parts can be reduced.

The supporting member 10 has the bimetal 3, the conductive path 4, and the fixed core 2 attached thereto.
The movable iron core 20 is attached via two return springs 1 and 1 so that the entire apparatus can be blocked and the circuit breaker 3
5 can be easily stored. further,
By projecting the pair of support portions 11 of the support member 10 forward from the pair of suction surfaces 2 a of the fixed iron core 2, the lower end side of the movable iron core 20 from the shaft support position is formed substantially linearly. The movable iron core 20 can be easily manufactured because it is not necessary to bend it specially.

On the other hand, as shown in FIG. 3, the spring mounting hole 26 in which the return spring 1 is mounted and the spring mounting groove 17 are shifted from each other in the height direction and the front-rear direction, so that the return spring 1 is (The front-rear direction of the device), the spring mounting hole 26 and the spring mounting groove 17 are kept at a distance that allows the same load to be applied as when not displaced.
, The distance in the front-rear direction can be narrowed to achieve compactness.

Further, between the fixed core 2 and the movable core 20, the conductive path 4 and the bimetal 3
Are arranged, it is not necessary to dispose the conductive path 4 and the bimetal 3 outside the fixed iron core 2 and the movable iron core 20, and it is possible to further reduce the size. (Embodiment 2) Since the basic configuration in this embodiment is common to Embodiment 1, the same reference numerals are given to the common parts, and the description thereof will be omitted, and only the characteristic parts of this embodiment will be described in detail. I do.

In this embodiment, as shown in FIGS.
The lower ends of the support portions 24a and 24b of the movable iron core 20 in the drawing are
It is characterized in that the shaft 21b is integrally formed by stamping outward.

In this embodiment, similarly to the first embodiment, the shaft 21b can be inserted into the pair of cut grooves 12, 12 at a time, and the pair of rotating shafts are supported one by one as in the conventional example. The movable core 20 does not need to be
It becomes easy to pivot to zero. Moreover, the movable core 20 and the shaft 21
Since b is formed integrally, the number of parts can be reduced as compared with the first embodiment, and the manufacturing cost can be reduced. Further, the shaft 21b integral with the movable iron core 20 can be easily formed by driving the support portions 24a and 24b.

[0028]

According to the first aspect of the present invention, a substantially U-shaped fixed member having a conductive portion serving as a current flow path of a circuit breaker and a pair of attracting surfaces which generate an electromagnetic force by energizing the conductive portion is provided on the front surface. An iron core, a substantially U-shaped support member having a pair of support portions protruding in the same direction as the pair of suction surfaces of the fixed iron core and disposed on the back side of the fixed iron core, and a support portion of the support member. One end of the movable core, which is mounted between the other end of the movable core and the support member, with a movable core whose one end side is opposed to each suction surface of the fixed core from one side of the substantially central portion and which is supported at both sides of the central portion. A return spring that urges the side away from each suction surface of the fixed core, sucks the movable core by electromagnetic force generated on the suction surface of the fixed core, and drives the tripping member by suction of the movable core. In the electromagnetic trip device of the circuit breaker that performs the interruption, it protrudes from both sides of the approximate center of the movable core In addition to the above, since a kerf is provided in each supporting portion of the support member on the side opposite to the pulling direction of the return spring, the kerf is provided so that the movable core can be easily supported by the support member by the kerf. By providing the shaft on the movable core, there is an effect that the shaft can be prevented from falling off after the movable core is attached to the support member.

According to the second aspect of the present invention, since the shaft is formed integrally from both sides of the movable iron core, it is not necessary to form the shaft with separate parts, the number of parts can be reduced, and the manufacturing cost can be reduced. There is an effect that can be.

According to the third aspect of the present invention, since the shaft is formed by stamping from both sides of the movable iron core, the shaft can be easily formed.

According to the fourth aspect of the present invention, the fixed core is attached to the inner surface of the support member, and the support portion of the support member is projected forward from the suction surface of the fixed core. Since the movable iron core is attached to the support member via the return spring, the entire device can be made into a block, and the storage work in the circuit breaker can be easily performed. By projecting the support portion to the front side from the suction surface of the fixed core, one end side can be formed in a substantially linear shape from the pivotal support position of the movable core, and there is no need for special bending. Therefore, there is an effect that the movable core can be easily manufactured.

According to a fifth aspect of the present invention, one end of the movable iron core is substantially opposed to each attracting surface of the fixed iron core, and one end of the movable iron core is brought into contact with the urging force of the return spring. Since the pair of movement preventing pieces positioned at the position are formed on the support member, one end side of the movable iron core is prevented from rotating beyond a predetermined range by abutting on the movement preventing piece. As a result,
Since a fixed distance is maintained between the fixed core and one end of the movable core, the electromagnetic attraction between the fixed core and one end of the movable core is constant, and the tripping characteristics can be stabilized,
Further, providing the movement preventing piece on the support member eliminates the need for a separate member for stopping the rotation of the movable iron core, and has the effect of reducing the number of parts.

According to the sixth aspect of the present invention, the return spring mounting positions of the support member and the movable iron core are shifted from each other in the height direction and the front-rear direction. Thus, the distance between the support member and the movable iron core in the front-rear direction can be reduced while maintaining the distance where the same load is applied as when not displaced, thereby achieving compactness. effective.

According to a seventh aspect of the present invention, the conductive portion and the heat generated by an overcurrent flowing through the conductive portion are displaced toward the fixed core from a position where the movable core is supported between the fixed core and the movable core. Since the thermal element which drives and disconnects the tripping member of the circuit breaker is arranged, there is no need to dispose the conductive part and the thermal element outside the fixed iron core and the movable iron core. There is an effect that it can be achieved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a first embodiment.

FIG. 2 is a perspective view of the same.

FIG. 3 is a side view of the same.

FIG. 4 is a sectional view of a main part of a circuit breaker using the same.

FIG. 5 is an exploded perspective view showing the second embodiment.

FIG. 6 is a perspective view of the same.

FIG. 7 is a side view of the same.

FIG. 8 is an exploded perspective view showing a main part of a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 return spring 2 fixed core 3 bimetal 4 conductive path 10 support member 11 support portion 12 kerf 13 movement prevention piece 20 movable core 21a shaft 24a, 24b support

Claims (7)

[Claims] A conductive part serving as a current flow path of the circuit breaker;
Fixed with a substantially U-shaped fixed core having a pair of suction surfaces on the front surface that generate electromagnetic force when electricity is supplied to the conductive portion, and a pair of support portions protruding in the same direction as the pair of suction surfaces of the fixed core. A substantially U-shaped support member disposed on the back side of the core, and both sides of the substantially central portion are supported by the support portion of the support member, and one end side from the substantially central portion is opposed to each suction surface of the fixed core. With a movable iron core,
A return spring mounted between the other end of the movable core and the support member to bias one end of the movable core away from each of the attraction surfaces of the fixed core; and an electromagnetic force generated at the attraction surface of the fixed core. In an electromagnetic trip device of a circuit breaker, which suctions a movable core by force and drives and trips a tripping member by suction of the movable core, a shaft protruding from both sides of a substantially central portion of the movable core is provided and supported. An electromagnetic trip device for a circuit breaker, characterized in that a cut groove for inserting a shaft is provided in a portion of each support portion of the member opposite to a pulling direction of a return spring. 2. The electromagnetic trip device for a circuit breaker according to claim 1, wherein the shaft is formed integrally from both sides of the movable iron core. 3. The electromagnetic trip device for a circuit breaker according to claim 2, wherein the shaft is formed by stamping from both sides of the movable iron core. 4. A fixed core is attached to an inner surface side of a support member, and a support portion of the support member is projected forward from a suction surface of the fixed core. An electromagnetic trip device for the circuit breaker according to the above. 5. A pair of ones which are substantially opposed to the attraction surfaces of the fixed iron core, one end of the movable iron core abuts by the biasing force of the return spring, and the one end of the movable iron core is located between the attraction surfaces of the fixed iron core. 5. The electromagnetic trip device for a circuit breaker according to claim 1, wherein the movement preventing piece is formed on the support member. 6. The electromagnetic trip of a circuit breaker according to claim 1, wherein the respective return spring mounting positions of the support member and the movable iron core are shifted from each other in a height direction and a front-rear direction. apparatus. 7. The circuit breaker is displaced by a heat generated by an overcurrent flowing through the conductive portion to a position closer to the fixed core than a position where the movable core is pivotally supported between the fixed core and the movable core. 7. The electromagnetic trip device for a circuit breaker according to claim 1, further comprising a thermal element that drives and trips the trip member.