JPH076681A - Movable contact device for circuit breaker - Google Patents

Abstract

PURPOSE:To improve contactability between movable and fixed contacts, in a movable contact device for electrically connecting a movable contact to a connection conductor in a fixed side by sliding contact. CONSTITUTION:A movable contact 1 is constituted by parallelly arranging two sheets of independent contacts 6, to mount a movable contact 7 divided into each contactor 6 on one end of the contactor, to also turnably connect the other end to a connection conductor 2 having three-topped fork-shaped contact pieces 2a, and in a contact spring 11 in both ends, the contact 6 slidably comes in pressure contact with the contact piece 2a. In each contactor 6, a latch mechanism consisting of a current limiting pin 10, current limiting latch 16 and a current limiting spring 18 is individually provided. Since the movable contact 7 is divided into two parts, a contact point with a fixed contact is increased, and since mass of the contact 6 is divided into two parts, inertia moment is decreased, to increase an opening speed of the movable contact 1 at the time of current limiting interruption.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable contactor device in a circuit breaker such as a wiring breaker or an earth leakage breaker.

[0002]

2. Description of the Related Art In the above circuit breaker, a flexible conductor has been generally used for the electrical connection between a movable contactor which is opened and closed and a connection conductor fixed to a main body case of the circuit breaker. . However, there is a risk that this flexible conductor may be fatigued and disconnected due to repeated bending actions associated with the opening and closing of the movable contact, and that the opening and closing characteristics may change due to variations in the resistance force that the movable contact receives from the flexible conductor. There's a problem. These problems are particularly significant in medium-sized or larger circuit breakers in which the rated current is large and therefore the flexible conductor is thick. Therefore, a pair of arms facing the connection end of the fixed-side connecting conductor with the movable contact is formed to sandwich the movable contact, and this arm is pressed against the side surface of the movable contact with a spring to move with the connecting conductor. A movable contactor device has been proposed in which the contactor is electrically connected by sliding contact and the flexible conductor is omitted (see Japanese Patent Application Laid-Open No. 4-19938).

[0003]

By the way, if the movable contact and the fixed contact are completely parallel in the width direction (left-right direction) in the closed state, the movable contact and the fixed contact are normally formed in an arc shape only in the front-rear direction. The contact surface of the movable contact and the contact surface of the fixed contact formed flat as a whole are in linear contact with each other in the left-right direction. But,
Considering an error in assembly and accuracy of parts, it is difficult to keep the movable contact and the fixed contact completely parallel to each other, and there is always an inclination in the width direction between them. In that case, in the above-mentioned sliding contact type movable contactor device, since the sliding contact portion of the movable contactor is sandwiched by the connecting conductors, there is a great constraint on the lateral tilting, and the movable contactor in the closed state. Even if the fixed contact is strongly pressed, there is little play such that the movable contact can change its posture so that the movable contact follows the fixed contact. As a result, a phenomenon occurs in which the movable contact and the fixed contact come into one-side contact with one of the left and right sides.

[0004] This small contact does not have a great influence in a small circuit breaker having a small rated current, but in a medium-sized or larger circuit breaker, the terminal temperature rises due to heat generation based on contact resistance. In particular, for example, in a large circuit breaker with a rated current of 600 A or more, the value of the energized current increases, while the thickness of the movable contactor and the width of the movable contact joined to it are 10
Since it is not less than mm, it is more difficult to secure the parallelism with the fixed contact as compared with a small-sized one, and the problem of heat generation due to the above one-sided contact becomes more serious. Therefore, an object of the present invention is to provide a sliding contact type movable contactor device in which the contact area between the movable contact and the fixed contact is increased and which is particularly suitable for a large-sized circuit breaker. is there.

On the other hand, the breaking ability of the circuit breaker is determined by how low the stress due to the arc energy generated at the time of breaking the current is suppressed, and a current limiting mechanism is generally used as a suppressing means. When the short-circuit current flows in the current limiting mechanism, the movable contact is rapidly opened prior to the normal opening operation due to the tripping operation of the switching mechanism, and the arc voltage is increased to interrupt the current limiting in a short time. It is a thing. In the latch release operation of the current limiting mechanism, electromagnetic repulsion force generated by currents flowing in different directions between two parallel conductors is usually used. According to this current limiting interruption, the current peak value and the passing I ² t value at the time of interruption of the short-circuit current are suppressed, and the thermal and mechanical stress of the electric circuit is greatly reduced.

The point of the current limiting interruption is to enhance the current limiting effect by increasing the opening speed of the movable contactor as much as possible and starting the generated arc from the stuck state to the active state in a short time. However, when the circuit breaker becomes large and the current carrying capacity becomes large, the mass of the movable contact increases accordingly, and as a result, the moment of inertia when the contacts open increases, which increases the opening speed of the movable contact. There was a problem that it would be difficult to raise it. In view of the above, according to the present invention, even in a large-capacity circuit breaker for which it has been difficult to obtain a current limiting effect, it is possible to easily move the circuit breaker so as to increase the opening speed of the movable contactor at the time of current limiting interruption. It is intended to provide a contactor device.

[0007]

SUMMARY OF THE INVENTION In order to increase the contact area between a movable contact and a fixed contact, the present invention arranges two contact bodies made of flat conductors in parallel independently of each other.
A movable contact for each phase is formed, and a movable contact is divided and attached to one end of the movable contact, and the other end of the movable contact is connected to a connection conductor having a three-pronged contact piece by a current-carrying pin. Contact springs are movably connected to each other, and contact springs for slidably pressing the contact piece and the contact piece are attached to both ends of the current-carrying pin. Further, in order to increase the opening speed of the movable contactor at the time of current limiting interruption, the present invention arranges two contactor bodies made of flat conductors in parallel independently of each other to provide a movable contactor for one phase. A current limiting mechanism is provided for each of the contact bodies. The movable contact device includes
It is advisable to insert a gap top between the two contact pieces to regulate the gap between the contact pieces and to interlock the contact pieces in the opening direction via appropriate play.

[0008]

The movable contact has two contact bodies, and the movable contact is divided and attached to each of them, so that the movable contact has a twin structure and the contact point with the fixed contact is double that of the single contact. At the same time, the large-sized wide contact is also divided into two parts, and the width is narrowed to improve the contact property. In addition, since the two contact bodies are independent of each other, even if the facing distance between the movable contact and the fixed contact differs on the left and right sides, the left and right contact bodies move up and down to fit the fixed contacts. Shake, the contact body is 1
The contact property is improved as compared with the case where two movable contacts are simply arranged side by side on one normal movable contactor. Further, the contact portion between the movable contactor and the connecting conductor is formed by connecting the two contactor bodies to the three-pronged contact piece of the connecting conductor so that the center contact piece serves as a common contact portion and the contact pieces on both sides respectively. It is possible to obtain a contact area that is twice as large as that in the case where the contact bodies are respectively sandwiched and one movable contact is sandwiched between the bifurcated connecting conductors.

On the other hand, by arranging two contact bodies made of flat conductors independently of each other in parallel to form a movable contact for one phase, and providing a current limiting mechanism for each contact body,
The mass per contact body is reduced to half, and the contact bodies can be independently driven by each current limiting mechanism to greatly increase the opening speed at the time of current limiting interruption. The current of each movable contact is shunted into two parallel contact bodies, and an electromagnetic attraction force acts between the two parallel currents flowing in the same direction. Therefore, when a large current such as a short-circuit current flows, there is a risk that the contact bodies will be attracted to each other and deformed, or adjacent split contacts will come into contact with each other and weld. Therefore, it is preferable to insert a gap top between the contact pieces to prevent the contact pieces from being deformed inward. However, this gap top also interlocks the opening operation of the two parallel arranged contact pieces. Therefore, it is preferable that these are connected to each other. However, an appropriate play is provided between the gap top and each contact element so that each contact element can be individually driven by the electromagnetic repulsive force when the current is cut off. As a result, at the time of current limiting interruption, the contacting elements operate independently of each other in the initial state of opening when the movable contactor is initially driven by the electromagnetic repulsion force, and in the opening operation after the spring action of the current limiting mechanism is applied. Move to interlocking operation and fully open.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention in a circuit breaker for three-pole wiring will be described below with reference to FIGS. First, FIG. 1 is an exploded perspective view showing one phase of the movable contact device, FIG. 2 is a vertical sectional view thereof, FIG. 3 is a perspective view of a gap top, and FIG. 4 is a rear view of a main part of FIG. 2 showing a current path. Is. In these figures, the movable contactor 1 has a connection conductor 2 and a conducting pin 3 penetrating them.
The connection conductor 2 is fixed to the main body case 4 of the circuit breaker with screws 5. The movable contactor 1 of each phase has a contactor body 6 formed by punching from a copper plate.
The movable contacts 7 are divided into two pieces and are joined to the tip of the contact body 6 with the same width. The movable contact 7 has a contact surface formed in an arcuate shape in the front-rear direction, and has a boat shape when viewed from the side. On the other hand, the fixed contact 9 joined to the fixed contact 8 fixed to the main body case 4 is an integral body that extends over the left and right pieces of the movable contact 7, and its contact surface is entirely flat. Energizing pin 3
The base end portion of the contactor body 6 which penetrates is bulged in a V shape in the lower part of the figure, and a current limiting pin 10 having a function to be described later is implanted near the tip end thereof so as to project outward. .

The connecting conductor 2 has a mountain shape as shown in the figure, which is composed of a three-pronged contact piece 2a and a mounting portion 2b, and is integrally formed by punching and bending a copper plate. Bearing bosses are formed on the left and right contact pieces 2a by burring around holes through which the current-carrying pins 3 pass. Movable contact 1
And the connection conductor 2, the two contact pieces 6 are the contact pieces 2 in the center.
a and the contact pieces 2a on both the left and right sides, respectively, are assembled so as to be sandwiched, and contacted slidably to each other by the contact springs 11 composed of compression coil springs attached to both ends of the current-carrying pin 3. ing. Between the left and right contactor bodies 6 of the movable contactor 1, a spacing frame 1 having the shape shown in FIG.
2 is inserted. The spacing top 12 is the central disk portion 12
a is the same thickness as the central contact piece 2a of the connection conductor 2, and this portion abuts the facing side surface of the contact body 6 to regulate the interval, and the shaft portions 12b at both ends are bearing holes of the contact body 6. 13 (FIG. 1). There is an appropriate amount of play between the bearing hole 13 and the shaft portion 12b, and the left and right contact bodies 6 can move within a range above and below each other.

The base end of the movable contactor 1 and the connecting conductor 2 are
Hollow insulation holder 14 made of molding resin and having the illustrated shape
Housed in. The insulating holders 14 of the respective phases are connected to each other by an integrally formed opening / closing shaft 15 (FIG. 1).
It is rotatably supported by the main body case 4 via. Inside the insulating holder 14, two right and left current limiting latches 16 are rotatably supported by a common support shaft 17. The current limiting latch 16 is formed by bending a steel plate, and
The support shaft 1 is constituted by a current limiting spring 18 formed of a compression spring, which is composed of a dogleg-shaped back wall forming a and 16b and both arms serving as bearings of the support shaft 17, and is inserted between the support holder 17 and the insulating holder 14.
It is urged in the clockwise direction of FIG. The movable contactor 1 and the connecting conductor 2 connected by the current-carrying pin 3 have a groove 1 on the inner wall surface of the insulating holder 14 shown in FIG.
9 and the movable contact 1 is inserted into the window hole 20 on the front surface so as to be combined with the insulating holder 14.
At that time, the left and right current limiting pins 10 projecting from the contactor plate 6 compress the current limiting spring 18 and two right and left current limiting latches 16 are provided.
The contact springs 11 that are respectively pressed against the current limiting surfaces 16a and are attached to the energizing pins 3 are compressed by the inner wall surface of the insulating holder 14.

As shown in FIG. 2, the insulating holder 14 in which the movable contact 1 is incorporated is rotatably fitted in the bearing groove formed in the phase gap wall (not shown) of the main body case 4, and the connecting conductor 2 is attached. It is fixed to the body case 4 as described above by the screw 5 screwed into the screw hole 21 (FIG. 1) of the portion 2b from the back side of the body case 4. The connecting conductor 2 is connected to a conductor 24 integral with the load side terminal by a screw 23 passing through the hole 22 (FIG. 1). Although not shown, the conductor 2
In the middle of 3, an overcurrent trip device including a bimetal 25 using this as a heater and an armature attracted to a fixed iron core surrounding the conductor 24 is provided. In the closed state of FIG. 2, the insulating holder 14 is held in the illustrated state by an opening / closing mechanism (not shown), and the movable contact 7 is pressed against the fixed contact 9. In this state, the movable contact 1 has the current limiting pin 10
Receives the force of the current limiting spring 18 from the current limiting latch 16 via
It is urged counterclockwise to obtain a predetermined contact pressure between the contacts 7 and 9. The current limiting spring 18 is a parent and child spring in which two springs having different winding directions and different diameters are concentrically combined, and generate a larger contact pressure than a single spring.

Here, the current limiting pin 10, the current limiting latch 16 and the current limiting spring 18 provided for each contact body 6 respectively constitute a current limiting mechanism, and the operation thereof will be described below. In the closed state of FIG. 2, the current limiting pin 10 that abuts on the latch surface 16a moves from the current limiting latch 16 to the current limiting spring 18a.
However, since the line of action of this force passes through the lower side of the center of the current-carrying pin 3 in the figure, the movable contact 1 is attached to the fixed contact 8 in the counterclockwise direction as described above. It is energized. Now, when a large current such as a short-circuit current flows, as shown by the arrow in FIG. 2, the movable contact 1 and the fixed contact 8 are moved by the electromagnetic repulsive force between the currents flowing in the parallel conductor portions in opposite directions. The child 1 is driven clockwise, and the contacts 7 and 9 are separated. At that time, when the movable contact 1 is slightly rotated clockwise, the contact point of the current limiting pin 10 is changed to the latch surface 16a.
To 16b, the current limiting spring 18 received by the current limiting pin 10
The line of action of the force passes through the upper side of the axis of the energizing pin 3 in the figure. As a result, the current limiting spring 18 for the movable contact 1 is
The action of is reversed from the counterclockwise direction to the clockwise direction, and the movable contact 1 is driven by both the electromagnetic repulsive force and the force of the current limiting spring 18 to rapidly separate the contacts 7 and 9. As a result, current limiting is interrupted without waiting for the drive of the insulating holder 14 by the opening / closing mechanism that is tripped by the operation of the overcurrent trip device.

In the above structure, the movable contactor 1 is composed of two contactor bodies 6 which are independent of each other, and the movable contact 7 is divided and attached thereto. Therefore, the movable contact 7 has twice the contact point as compared with the case of a single unit, and the width of each is halved to improve familiarity with the fixed contact 9, so that a large contact area can be obtained. In addition, even if the movable contact 1 tends to fall laterally as a whole due to an assembly error or the like, and the parallelism between the movable contact 7 and the fixed contact 9 on the left and right is poor, each of the divided contactor bodies is divided. The left and right movable contacts 7 are always in contact with the fixed contact 9 in accordance with the fixed contact 9. Therefore, when the movable contact 7 divided into the right and left is brought into contact with the fixed contact 9, the contact resistance of each is obtained when the single movable contact in which the left and right movable contacts 7 are integrated is brought into contact with the fixed contact 9. Can be smaller. An example thereof is as follows. A single movable contactor with a rated current capacity of 800 A and a single contact with a cross section of 10 mm x 9 mm, and an ordinary silver alloy contact 2 with a flat cross section of 10 mm x 4 mm, which is obtained by dividing this contact into two. When the contact resistance of the movable contact having a divided structure according to the present invention is measured, the contact resistance of the single movable contact is 4
The contact resistance of the split movable contact was 37.7 μΩ on the left and 33.4 μΩ on the right. The contact resistance was measured by setting the contact pressure to 10 kg and passing a direct current of 100 A. In this case, the current I flowing in each phase is divided into I ₁ and I ₂ by the movable contact 7 as shown in FIG. 1 and flows through the left and right contact bodies 6, and these currents are further divided as shown in FIG. At the contact portion with the connecting conductor 2, the current is divided into I ₁₁ and I _12, and I ₂₁ and I ₂₂ , respectively. Therefore, in this case, the amount of heat generated at the contact portion between the movable contact 7 and the fixed contact 9 is larger in the movable contact having the divided structure as described above than in the case of the single movable contact.
Although the contact resistance between them becomes small, for the sake of simplicity, if the contact resistance between the two is R and the current is I ₁ ≈I ₂ ≈I / 2,
(I / 2) ² · R + (I / 2) ² · R = (I ² R) / 2
The heat generation amount I ^{2 in} the case of the left and right integrated movable contacts
It becomes half of R.

Similarly, the amount of heat generated at the contact portion between the movable contact 1 and the connection conductor 2 is, for the sake of simplicity, the contact body 6 and the contact piece 2a.
The contact resistance between and is r, I ₁₁ ≈I ₁₂ ≈I ₂₁ ≈I ₂₂ ≈I /
When it is 4, it is represented by (I ² r) / 4, which is half of the heat generation amount (I ² r) / 2 when the movable contact made of one contact body is sandwiched by the bifurcated connecting conductors. On the other hand, in FIG.
Currents I ₁ flowing in the same direction in the left and right contact bodies 6,
Electromagnetic attraction acts between I ₂ . This electromagnetic attraction force tends to bend the contact pieces 6 when a short-circuit current passes, but in the illustrated embodiment, the gaps 12 are inserted so that the contact pieces 6 are prevented from approaching each other, and the contact pieces 6 are prevented from approaching each other. There is no danger that 6 will be deformed or that the left and right movable contacts 7 will contact each other and will be welded. In addition, the movable contactor 1 of each phase is composed of two contactor bodies 6, and these contactor bodies 6 have a play range between the shaft portion 12b of the gap top 12 and the bearing hole 13 at the time of current limiting interruption. They are driven independently of each other by electromagnetic repulsive force, and are then driven at high speed in conjunction with the full-open position by the action of the current limiting springs 18 as described above.

That is, the movable contactor 1 has two contactor bodies 6
The mass of the movable contact is divided into a single piece and receives the electromagnetic repulsion force and the force of the current limiting spring 18, which is half of that of a normal movable contact made of an integral conductor. The opening speed of the contact 1 is increased. As a result, the time until the movable contactor 1 receives an electromagnetic repulsive force to start the operation of the current limiting mechanism (arc sticking time), and the operation of the current limiting mechanism causes the movable contactor 1 to fully open to generate an arc. The time to start up to the active state (arc voltage rise time) can be suppressed to the level of a small-capacity circuit breaker even in a large circuit breaker. 5 and 6 show an example in which the maximum passing current peak value and passing I ² t at 460 V, 65 kA interruption are measured for a circuit breaker of 800 A frame and the conventional circuit breaker using the movable contactor of the present invention. The circuit breaker of FIG. As shown in the figure, according to the present invention, both the maximum passing current peak value and the passing I ² t are significantly reduced, and accordingly, the thermal and mechanical stress on the case and the cover is suppressed. It should be noted that the electrical connection between the movable contactor 1 and the connection conductor on the fixed side does not necessarily have to be sliding contact as in the illustrated embodiment as long as it is only for improving the current limiting interruption performance, and it is not necessary to use conventional flexible cables. Connection by conductor is acceptable.

7 and 8 show different embodiments of the connecting conductor 2, FIG. 7 is a perspective view of one side, and FIG. 8 is a rear view of the connecting conductor 2 connected to the movable contact 1. In the embodiment of FIG. 1, the entire connecting conductor 2 is integrally formed by bending, whereas in this embodiment, the connecting conductor 2 has a three-pronged shape in which a pair of bifurcated conductors 2A and 2B of different left and right are butted against each other. Is formed in. The bifurcated conductors 2A and 2B sandwich the left and right contactor bodies 6 of the movable contactor 1, respectively, and are butted against each other. According to such a configuration, the press molding is simpler and the manufacturing cost is lower than that of FIG. 1 in which the central common contact piece is integrally formed.

Next, FIG. 9 is a rear view of the essential parts showing an embodiment in which the contact portion between the movable contact 1 and the connecting conductor 2 is spherical.
That is, in this embodiment, the contact piece 2a of the connection conductor 2 is formed with a spherical convex portion, and the contact body 6 is formed with a spherical concave portion having a slightly larger radius of curvature. These concave and convex portions are overlapped with each other as shown in the drawing, and slidably pressed against each other by the contact spring 11. Further, in this case, an appropriate play is provided between the current-carrying pin 3 and the hole of the contactor body 6 through which the current-carrying pin 3 penetrates. With such a configuration, the contact body 6 can be rotated with respect to the connection conductor 2 as indicated by an arrow in the figure, and the constraint of the connection conductor 2 against the lateral inclination of the contact body 6 is weakened. Become. Therefore,
As described above, when the parallelism in the left-right direction between the movable contact 7 and the fixed contact 9 is poor, the contact body 6 causes the fixed contact 9 to move.
It becomes easy to change the tilted posture in the left-right direction in accordance with the above, and the movable contact 7 becomes more familiar to the fixed contact 9 and the contact property is further improved.

[0020]

As described above, according to the present invention, the number of contact bodies of the movable contact is two, and the movable contact is divided and attached to each of them, so that the contact point with the fixed contact is the normal contact. In addition, the large contact having a large width is also divided into two, and the width is narrowed, so that the contact property is improved. In addition, since the contact bodies are independent on the left and right, even if the facing distance between the movable contact and the fixed contact differs on the left and right sides, the left and right contact bodies swing up and down so that they fit into the fixed contacts. ,
This surface also has good contact. Therefore, in the case of a large circuit breaker with a large contact width, if the parallelism between the contacts in the left-right direction is poor due to assembly error or component accuracy, or if the contact surface of the fixed contact rises due to thermal damage after overload current trip, Even when a dent or the like occurs, the movable contact easily follows the fixed iron core contact, the contact area increases, and heat generation decreases. Furthermore,
By slidably connecting the movable contactor to a connecting conductor having a trifurcated contact piece, each contact piece can be sandwiched between the contact pieces on both sides with the central contact piece as a common contact portion. Provides a contact area twice as large as when one contact conductor sandwiches two contact bodies, or when one contact body sandwiches one movable contact between two forked connection conductors, and even by sliding contact It is possible to provide a sufficient current-carrying capacity between the movable contact and the connection conductor.

Further, two contact bodies made of flat conductors are independently arranged in parallel with each other to form a movable contact for one phase, and a current limiting mechanism is provided for each contact body to limit the current. Even in large-capacity circuit breakers, which are said to be difficult to produce the current limiting effect because the mass to be driven by electromagnetic repulsion force and current limiting spring force at the time of interruption is half, it is easy to increase the opening speed of the movable contactor Power can be significantly reduced.
In such a movable contactor device, an interval between two contactor bodies is regulated, and the contactor bodies are interlocked in the opening direction via appropriate play. By inserting the top, it is possible to effectively prevent the contact body from being deformed and the divided contacts to be welded to each other due to the electromagnetic attraction force between the contact bodies even when a large current flows. The body can be interlocked without impairing the independent operation in the initial state of opening when the current limiting is cut off.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of one phase of a movable contact device according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of the movable contactor device of FIG.

FIG. 3 is a perspective view of the spacing frame in FIG.

FIG. 4 is a rear view of the main part of FIG.

5 is a diagram showing a relationship between a standard short-circuit current and a maximum passing current peak value of a circuit breaker equipped with the movable contact device of FIG. 1 in comparison with a conventional circuit breaker.

FIG. 6 is a diagram showing the relationship between the standard short-circuit current and the passing I ² t of the circuit breaker including the movable contactor device of FIG. 1 in comparison with the conventional circuit breaker.

FIG. 7 is a perspective view showing another embodiment of the connecting conductor.

8 is a rear view of the essential parts of a movable contact device using the connecting conductor of FIG.

FIG. 9 is a rear view of the essential parts showing an embodiment in which the contact surfaces of the movable contactor and the connection conductor are different.

[Explanation of symbols]

 1 Moving Contact 2 Connection Conductor 3 Energizing Pin 4 Main Body Case 6 Contact Body 7 Moving Contact 8 Fixed Contact 9 Fixed Contact 10 Current Limit Pin 11 Contact Spring 12 Spacing Frame 14 Insulation Holder 15 Open / Close Shaft 16 Current Limit Latch 17 Spindle 18 Current limiting spring

Claims (3)

[Claims] 1. A movable contact for one phase is formed by arranging two contact bodies made of flat conductors independently of each other in parallel, and a movable contact is divided at one end thereof for each contact body. At the same time as mounting, the other end of this movable contact is rotatably connected to a connection conductor having a three-pronged contact piece by a current-carrying pin,
A movable contactor device for a circuit breaker, wherein contact springs for slidably press-contacting the contact body and the contact piece are mounted on both ends of the energizing pin. 2. A movable contact for one phase is formed by arranging two contact bodies made of a flat conductor independently of each other in parallel, and a current limiting mechanism is provided for each contact body. Movable contact device for circuit breaker. 3. A gap top is inserted between the two contact pieces to regulate the gap between these contact pieces and to interlock these contact pieces in the opening direction through appropriate play. The movable contactor device for a circuit breaker according to claim 1 or 2, characterized in that.