JPH11273536A - Multi-point cutting type circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-point cutting type circuit breaker having high reliability of stabilizing contact of contacts and capable of shutting and short circuiting, regarding a circuit breaker for opening or closing a pair of two contacts. SOLUTION: This circuit breaker comprises a first fixed contact 54 connected with an electric power terminal 53, a second fixed contact point 56 connected with a trigger apparatus, and a bridge contactor 57 comprising movable contacts 58, 59 in both end parts as to bridge both fixed contacts 54, 56 at the time of closing. In the circuit breaker, the center part of the bridge contactor 57 is so journalled with a movable contactor arm 60 driven by a switchgear mechanism as to move the movable contacts 58, 59 in both ends of the bridge contactor 57 like a seesaw in the directions toward the fixed contacts 54, 46.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker which opens and closes with two contact pairs, and more particularly to a structure for stabilizing contact between contacts.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a side cross-sectional view of a conventional multi-point circuit breaker disclosed in Japanese Patent Application Publication No. H10-206, with a part thereof being cut away. FIG. 8 is an explanatory diagram showing the relationship between the power supply side terminal and the intermediate terminal. FIG. 9 is a plan view showing a movable contact portion of the multi-point circuit breaker shown in FIG.
FIG. 10 is a sectional view taken along the line AA in FIG. In the figure, 1 is a base, 2 is a cover, and 3 is a handle, all of which are formed of a mold insulating material. Reference numeral 4 denotes a cartridge case formed of an arc-resistant mold insulating material, which is mounted inside the base 1. Reference numeral 5 denotes a power-supply-side terminal mounted on the cartridge case 4;
As shown in the figure, a first conductor 5a for connecting an external electric wire,
A second conductor 5b bent at a right angle from the first conductor 5a toward the bottom surface of the cartridge case 4 and a second conductor 5b bent at a right angle from the second conductor 5b as shown in FIG. A third conductor portion 5c extending along the outer periphery, and a fourth conductor portion 5c formed so as to be bent at a right angle from the third conductor portion 5c and become a slope.
5d. The portion of the fourth conductor portion 5d is located inside the cartridge case 4 and the fixed contact 6 is fixed thereto.

[0003] Reference numeral 20 denotes an intermediate terminal having a conductor portion 20a having a slope at one end. This conductor portion 20a is located inside the cartridge case 4, and is juxtaposed with the fourth conductor portion 5d of the power supply side terminal as shown in FIG.
1 is fixed. The other end of the intermediate terminal 20 is electrically connected to a connection conductor 23 that supplies a current to a trip device (not shown). 22 is a connection screw. Reference numeral 25 denotes an opening / closing mechanism, and reference numeral 26 denotes an arc extinguishing device, which is installed inside the cartridge case 4 corresponding to the respective positions of the fixed contacts 6 and 21.

[0004] Reference numeral 7 denotes a U-shaped fork-shaped mover. As shown in FIG. 9, movable contacts 8 and 9 are fixed to the tips of a pair of contact arms 7a and 7b. Reference numeral 10 denotes a mover arm, one end of which is fixed to the base conductor 7c of the mover 7 and is rigid. The other end of the armature 10 is rotatably supported by an armature pin 16 provided on a crossbar 15 made of an insulating material. Reference numeral 17 denotes a contact pressure spring, a pair of winding portions 17a are fitted into the recesses 15a of the crossbar 15, and the operating portion 17b engages with the recesses 7d of the mover 7, and as shown in FIG. It is urged in the counterclockwise direction (arrow B direction). FIG. 11 is an enlarged side sectional view showing a conventional multipoint circuit breaker, and shows details of the power supply terminal 5, the contact pressure spring 17, and the like.

Next, a description will be given of a conventional contact stabilization technique for a multipoint breaker circuit breaker. Regarding the relationship between the fixed contact 6 of the power supply side terminal 5 mounted on the base 1 and the fixed contact 21 of the intermediate terminal 20, a difference occurs in the distance from the position of the mover 7 with respect to the positions of the fixed contacts 6 and 21. There is. That is, the position of each part may change due to a processing error or an assembly error of the part. Usually, in order to cope with this change in position, the through hole 10 of the armature arm 10 is used.
a between the armature 10 and the armature 10
Can be tilted with respect to the mover pin 16. By this tilting, the contact is stabilized.

[0006] The current flowing through the circuit breaker is changed from the first conductor 5a of the power supply terminal 5 to the second conductor 5b to the third conductor 5b.
c → fourth conductor 5d → fixed contact 6 → movable contact 9 → contact arm 7b of mover 7 → base conductor 7c → contact arm 7a
→ Movable contact 8 → fixed contact 21 → intermediate terminal 20 → connection terminal 23 → tripping device (not shown) → flow side terminal (not shown). Thus, the circuit breaker is configured to be in a closed state (ON state) by bridging the fixed contact 6 and the fixed contact 21 with the mover 7.

[0007]

In the above-mentioned conventional multi-point breaker circuit breaker, the fixed contact 6 of the power supply terminal 5 and
Regarding the relationship between the fixed contact 21 of the intermediate terminal 20 and the mover 7
When there is a difference in the distance from the armature 10, the urging force of the contact pressure spring 17 acts between the armature pin 16 and the armature arm 10, and the urging force is applied to the armature pin 16 of the armature arm 10. To the fixed contact 6
And 21 and the movable contacts 8 and 9 have a problem that stable contact cannot be obtained.

The current flowing through the second conductor 5b of the power supply terminal 5 is disposed in a direction opposite to the direction of the current flowing through the base conductor 7c of the mover 7 (indicated by the arrow in FIG. 8). I have. Therefore, a short circuit current flows in the electric circuit,
When the movable contacts 8, 9 of the mover 7 are to be separated from the fixed contacts 6, 21 by the opening / closing mechanism 25, an electromagnetic force is applied between the second conductor 5 b of the power supply terminal 5 and the base conductor 7 c of the mover 7. Since a repulsive force is generated, the mover 7 prevents the mover 7 from separating in the direction of arrow C (shown in FIG. 11) using the mover pin 16 as a fulcrum, and the moving speed of the mover 7 at the time of short-circuit interruption is delayed. ,
There was a problem that the blocking performance was reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and in a circuit breaker that opens and closes with two contact pairs, a multipoint having high contact stability reliability of contacts and excellent short-circuit breaking performance. The purpose is to obtain a cut-off circuit breaker.

[0010]

In a multi-point circuit breaker according to the present invention, a first fixed contact connected to a power supply terminal, a second fixed contact connected to a trip device,
A movable contact arm driven and opened and closed by the opening and closing mechanism, wherein the movable contact arm is provided with movable contacts at both ends so as to bridge the two fixed contacts when closed. The center of the bridging contact is supported at the tip so that the movable contacts at both ends of the bridging contact can rotate in a seesaw shape in the direction of the fixed contact.

A bridging contact is formed in a U-shape to provide movable contacts at both ends, and a second conductor connected to a power supply terminal and having a first fixed contact and a second conductor connected to a tripping device. The bent portion formed in the second conductor having a fixed contact and a part of the second conductor is opposed to one end electric circuit, the other end electric circuit, and the central electric circuit of the U-shaped bridging contact, respectively. The bridge contacts are electromagnetically repelled when a short-circuit current occurs by arranging them so that currents in opposite directions flow through the opposing electric paths and conductors.

Further, in a state in which one of the movable contacts provided on the bridging contact is in contact with the fixed contact, a connection provided on the bridging contact rotatably supported by the movable contact arm. The center position of the hole is disposed closer to the bottom surface of the base than the contact point between the movable contact and the fixed contact provided on the bridging contact.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a cross-sectional view showing a multipoint circuit breaker according to an embodiment of the present invention. FIG. 2 is a perspective view showing a movable contact portion of the multi-point circuit breaker of FIG. FIG. 3 is a perspective view showing a relationship between a movable contact portion and a fixed contact portion. In the figure, 51 is a base and 52 is a cover, both of which are formed of synthetic resin. Reference numeral 53 denotes a power supply terminal attached to the base 51, and a first fixed contact 54 is fixed to a tip end. 55
Is a connection conductor connected to the trip device 72, and a second fixed contact 56 similar to the first fixed contact 54 is fixed thereto. The first fixed contact 54 and the second fixed contact 56 are shown in FIG.
Are juxtaposed as shown in FIG.

Reference numeral 57 denotes a bridging contact formed of, for example, copper or a copper alloy material in a U-shape. The bridging contact 57 has a connecting hole 57b in a base conductor 57a and two contact arms 57 extending in parallel.
Movable contacts 58 and 59 are fixed to the tips of c and 57d, respectively. With this bridging contact 57, the first fixed contact 54 and the second fixed contact 56 are bridged, and the circuit breaker is closed (ON state). Reference numeral 60 denotes a movable contact arm, which is formed of an insulating material such as a synthetic resin material, or formed by forming a metal plate by plastic working and then performing an insulating process on the surface thereof.
7, a pair of protrusions 60b protruding from the boss 60a, and a holding portion 60c held at the other end by the contact pressure spring 61 and the mover pin 62 on the cross bar 63. have. The bridging contact 57 is
The movable contact arm 60 is rotatably inserted into the boss 60a, and the movable contacts 58 and 59 are positioned by the boss 60a and the protrusion 60b at the tip so as to face the fixed contacts 54 and 56. In the positioned state, it can be rotated in a seesaw shape as shown by the dashed line arrow DE in FIG.

In FIG. 1, the mover arm 60 is urged clockwise about a mover pin 62 by a contact pressure spring 61. Therefore, when the circuit breaker is closed, the movable contacts 58 and 59 of the bridging contact 57 allow the power supply terminal 5 to be closed.
The third fixed contact 54 and the second fixed contact 56 of the connection conductor 55 are configured to bridge. Note that 7
Reference numeral 0 denotes an upside down handle, 71 denotes an opening / closing mechanism driven by the handle 70 or the overcurrent trip device 72, 72 denotes a known trip device, and 73 denotes an arc extinguishing device.

In the multi-point circuit breaker thus configured, the imbalance of the contact pressure caused by the difference in the positions of the fixed contacts 54 and 56 is reduced by the U-shaped bridging contact 5.
7 and the boss portion 60 of the movable contact arm 60.
Since it can be rotated and absorbed in a seesaw shape by the clearance with a, the contact of the contact can be stabilized with high reliability.

Embodiment 2 FIG. FIG. 3 is an enlarged perspective view showing in detail a relationship between a contact portion and a fixed contact portion of the multipoint circuit breaker shown in FIG. In the figure, the relationship between the U-shaped bridging contact 57, the power supply terminal 53 and the connection conductor 55 is such that the first conductor, that is, the power supply terminal conductor 53a is disposed so as to face the electric path of the contact arm 57c, and the contact arm 57d Conductor, that is, the first connection conductor 5
5a, and a bent portion formed on a part of the first connection conductor 55a, that is, a second connection conductor 55b is provided so as to face the base conductor 57a as the central electric circuit.

By arranging in the above relationship,
The directions of the currents flowing through the U-shaped bridging contact 57, the power supply terminal 53, and the respective conductors / conductors of the connection conductor 55 are configured such that the directions of the currents flow in opposite directions as indicated by arrows in FIG. 3. You. With this configuration, the bridging contact 57
An electromagnetic repulsive force can be obtained between the power supply terminal 53 and the conductor of the connection conductor 55 facing each of the electric paths 57a, 57c and 57d. Due to the electromagnetic repulsion, the bridging contact 57 can be more quickly opened at the time of short-circuit interruption, and the interruption performance can be improved.

Embodiment 3 FIG. 4 is a side sectional view showing a multipoint breaker circuit breaker according to Embodiment 3 of the present invention. FIG. 5 is an exploded perspective view showing a movable contact portion of the multi-point circuit breaker shown in FIG. FIG. 6 is an explanatory diagram showing the relationship between the rotation center position of the bridging contact and the contact position of the contact. In the figure, 51-56, 61-63, 70-72
Are the same as those in the first embodiment, and a description thereof will be omitted. Reference numeral 157 shown in FIG. 5 is a bridging contact formed of, for example, copper or a copper alloy material in a U shape, having a connecting hole 157b in the base conductor 157a, and the tip of two parallel contact arms 157c and 157d. The movable contacts 158 and 159 are fixed to the portions, respectively. This bridging contact 157 allows the first fixed contact 54 and the second fixed contact 5
6 is bridged, and the circuit breaker is closed (ON state).

Reference numeral 160 denotes a movable contact arm formed in substantially the same shape as the movable contact arm 60 of the first embodiment, and is formed of an insulating material such as a synthetic resin material,
Alternatively, after a metal plate is formed by plastic working, the surface is subjected to insulation treatment, and formed at one end with a connecting hole 1 of a bridging contact 157.
A boss portion 160a engaging with the boss portion 57b;
a and a contact pressure spring 6 at the other end.
1 and a holding portion 160c held by the crossbar 63 by the mover pin 62. The bridging contact 157
As shown in FIG. 4, the position of the connection hole 157b is such that the bridging contact 157 is incorporated in the movable contact arm 160, and one of the movable contacts 158 and 159 provided on the bridging contact 57 is fixed. In a state where one of the contacts 54 and 56 is in contact, the connection hole 5 of the bridging contact 57 shown in FIG.
It is arranged closer to the bottom surface 51a side of the base 51 than the position 7b, that is, it is formed by moving in the direction of the connection conductor 55.

The bridging contact 157 is a movable contact arm 1
60 is rotatably inserted into the boss portion 160a of the boss portion 60a.
The movable contact 158,
159 are positioned so as to face the fixed contacts 54 and 56. In the positioned state, it can be rotated in a seesaw shape in the same manner as shown by the dashed line arrow DE in FIG.

The connecting hole 157b of the bridging contact 157
4, the bridging contact 157 is incorporated in the movable contact arm 160, and the movable contacts 158 and 159 are moved to the center position C1 where the bridging contact 157 rotates in a seesaw shape, as shown in FIG. When the movable contacts 158, 159 and the fixed contacts 54,
The base 51 is disposed closer to the bottom surface 51a of the base 51 so as to be lower than the point of contact with the base 56, that is, the first connection conductor 55a55, which is the second conductor.

An operation state when the bridging contact 157 contacts the fixed contacts 54 and 56 will be described with reference to FIG.
FIG. 6A is an explanatory diagram illustrating an operation state in the configuration of the first embodiment. In the figure, reference numerals 54 and 56 denote positions of fixed contacts. The movable contacts 158 and 159 indicated by solid lines are positions at which the movable contact 159 starts to contact the second fixed contact 56. C1 is the movable contact 159 of the bridging contact 157
Is the center position of the connection hole 157b of the bridging contact 157 when it starts to contact the second fixed contact 56. L1 is the distance between the center position of the connection hole 157b and the end surface of the movable contact 159 when the movable contact 159 starts to contact the second fixed contact 56.

Movable contacts 158 and 159 indicated by hatching
Means that both movable contacts 158 and 159 are fixed contacts 54 and 5
This is the position when 6 is completely touched. C2 is the center position of the connection hole 157b of the bridging contact 157 when both movable contacts 158, 159 are completely in contact with the fixed contacts 54, 56. H is the distance between the center position C2 of the connection hole 157b and the contact point between the movable contacts 158, 159 and the fixed contacts 54, 56.

The center positions C1, C of the connection holes 157b
Reference numeral 2 is disposed above the contact point between the movable contacts 158 and 159 and the fixed contacts 54 and 56, that is, at a position away from the bottom surface 51a of the base 51. Embodiment 1
According to the configuration, the movable contact 159 is connected to the second fixed contact 5
6 and complete contact with the movable contact 159
Completes the sliding contact while pressing on the second fixed contact 56 as shown by the arrow M, the frictional force between the second fixed contact 56 and the movable contact 159 increases, and both movable contacts 1
Until the fixed contacts 54 and 56 are completely contacted by the fixed contacts 58 and 159, the movable contacts 158 and 159 are likely to be lifted and the contact pressure to be unbalanced.

FIG. 6B is an explanatory diagram showing an operation state of the third embodiment. In the figure, reference numerals 54 and 56 denote positions of fixed contacts. The positions of the movable contacts 158 and 159, the positions of the movable contacts 158 and 159 indicated by oblique lines, and the connection holes 157.
The center positions C1, C2, and H of b are the same as those in FIG.
This is the same as that described in (A), and a description thereof will be omitted. In the configuration of the third embodiment, as shown in FIG. 4, the movable contact 158 provided on the bridging contact 157,
When one of the fixed contacts 54, 56 contacts one of the fixed contacts 54, 56, the center position C1 of the connection hole 157b of the bridging contact 157 is set to the movable contact 158, 159.
It is arranged close to the bottom surface 51a of the base 51 so as to be lower than the contact point between the fixed contact 54 and the fixed contact 54, 56, that is, on the connection conductor 55 side as the second conductor. L2 is the distance between the center position of the connection hole 157b and the end surface of the movable contact 159 when the movable contact 159 starts to contact the second fixed contact 56.

According to the configuration of the third embodiment, in order for the movable contact 159 to come into contact with the second fixed contact 56 and to come into complete contact therewith, the movable contact 159 is rotated as shown by the arrow N while rotating the second contact 159. Of the connection hole 1 is completed.
Since the distance L2 between the center position of the movable contact 157b and the end surface of the movable contact 159 when the movable contact 159 starts to contact the second fixed contact 56 is longer than the distance L1 shown in FIG. The frictional force of the movable contact 159 in contact with the fixed contact 56 of the second contact becomes small, and the floating contact and the contact pressure of the movable contact 158, 159 are required until both the movable contacts 158, 159 are completely in contact with both the fixed contacts 54, 56. This makes it difficult for unbalance to occur, and the contacts are smoothly and well-balanced, so that the contact pressures of both contacts are uniform and wear and welding of the contacts are reduced.

In the configuration of the third embodiment, the center position C2 of the connection hole 157b is
Although the distance from the contact point between the fixed contacts 8 and 159 to the fixed contacts 54 and 56 has been described as H, when this H is zero, that is, the center position C2 of the connection hole 157b and the movable contacts 158 and 159
When the contact points between the fixed contacts 54 and 56 are in the horizontal position, the movable contacts 158 and 1 that contact the fixed contacts 54 and 56
59 has the lowest frictional force.

[0029]

Since the present invention is configured as described above, it has the following effects.

Since the U-shaped bridging contact is rotatable around the boss of the movable contact arm, the difference in the positions of the two fixed contacts is absorbed when the electric circuit is closed, and the reliability is improved. High and stable contact contact can be obtained.

Since the power paths and the conductors of the power supply terminal and the connection conductor facing all three sides of the U-shaped bridging contact are arranged so that the current directions are opposite to each other, the bridge is formed. Electromagnetic repulsion acting on the entangled contact increases,
Opening the bridging contact faster and faster, improving the breaking performance.

Further, when one of the movable contacts provided on the bridging contact is in contact with the fixed contact, a connection provided on the bridging contact rotatably supported by the movable contact arm. Since the center position of the hole was located on the bottom side of the base from the contact point between the movable contact and the fixed contact provided on the bridging contact, by the time both movable contacts completely contact the fixed contact, Lifting of the movable contact and unbalance of the contact pressure are less likely to occur, and the contacts are smoothly and well-balanced, so that the contact pressure of both contacts is uniform, and wear and welding of the contacts are reduced.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a multipoint breaker circuit breaker according to Embodiment 1 of the present invention.

FIG. 2 is an exploded perspective view showing a movable contact portion according to the first embodiment of the present invention.

FIG. 3 is an enlarged perspective view of a main part showing a relationship between a contact part and a fixed contact according to a second embodiment of the present invention.

FIG. 4 is a side sectional view showing a multipoint breaker circuit breaker according to Embodiment 3 of the present invention.

FIG. 5 is an exploded enlarged perspective view showing a movable contact portion of the multi-point circuit breaker shown in FIG.

FIG. 6 is an explanatory diagram showing a relationship between a rotation center position of a bridging contact and a contact position of a contact according to the present invention.

FIG. 7 is a side sectional view showing a conventional multi-point circuit breaker.

FIG. 8 is an explanatory diagram illustrating a relationship between a power supply side terminal and an intermediate terminal.

FIG. 9 is an enlarged plan view showing a movable contact portion of a conventional multipoint breaker circuit breaker.

FIG. 10 is an enlarged sectional view taken along line AA of FIG. 9;

FIG. 11 is an enlarged sectional view showing a conventional multi-point circuit breaker.

[Explanation of symbols]

51 base, 51a bottom surface, 53 power terminal, 54
First fixed contact, 56 second fixed contact, 55 connecting conductor, 55a first connecting conductor, 55b second connecting conductor, 57,157 bridging contact, 58,59,158,
159 movable contact, 60,160 movable contact arm,
71 Opening / closing mechanism, C1, C2 Center position of connecting hole of bridge contact.

Claims (3)

[Claims] 1. A first fixed contact connected to a power supply terminal, a second fixed contact connected to a trip device, and an opening / closing drive by an opening / closing mechanism, and when closing, the two fixed contacts are bridged. A movable contact arm provided with movable contacts at both ends so that the movable contact arm is driven to be opened and closed by the opening and closing mechanism, and the bridging contact is provided at the tip of the movable contact arm. A center portion of the bridging contact is supported so that movable contacts at both ends of the bridging contact can rotate in a seesaw shape in the direction of the fixed contact. 2. A bridge contact is formed in a U-shape, movable contacts are provided at both ends, and a second conductor connected to a power supply terminal and having a first fixed contact and a second conductor connected to a trip device. The second conductor having the fixed contact and the bent portion formed in a part of the second conductor are respectively connected to one end electric circuit, the other end electric circuit, and the central electric circuit of the U-shaped bridging contact. 2. The bridging contact is electromagnetically repelled when a short-circuit current is generated by arranging them so as to face each other and allowing currents in opposite directions to flow through each of the opposing electric paths and conductors. Multi-point circuit breaker. 3. A connection provided on the bridging contact which is rotatably supported by the movable contact arm when one of the movable contacts provided on the bridging contact is in contact with the fixed contact. The center position of the hole is arranged on the bottom surface side of the base with respect to the contact point between the movable contact and the fixed contact provided on the bridging contact. Multi-point circuit breaker.