JP3206696B2 - Movable contact device for circuit breakers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art In the above-mentioned circuit breaker, a flexible conductor is generally used for electrical connection between a movable contact for opening and closing operation and a connection conductor fixed to a main body case of the circuit breaker. . However, there is a danger that this flexible conductor will break due to fatigue due to the repetitive bending action accompanying the opening and closing operations of the movable contact, and that the opening and closing characteristics of the movable contact will change due to variations in the resistance force received from the flexible conductor. There's a problem. These problems are particularly significant in medium or larger circuit breakers where 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 connection conductor with the movable contact is formed to sandwich the movable contact, and this arm is pressed against the side of the movable contact with a spring to move the connection conductor. There has been proposed a movable contact device in which a contact is electrically connected by sliding contact and the flexible conductor is omitted (see JP-A-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, they are usually formed in an arc only in the front-rear direction. The contact surface of the movable contact and the contact surface of the fixed contact formed flat overall are in linear contact in the left-right direction. But,
In consideration of assembly errors and component accuracy, it is difficult to keep the movable contact and the fixed contact completely parallel, and there is always a slight inclination between them in the width direction. In that case, in the above-mentioned sliding contact type movable contact device, since the sliding contact portion is sandwiched between the connecting conductors, the movable contact is largely restrained from falling in the left-right direction. There is little play such that the movable contact can change its posture so that the movable contact is along the fixed contact even if the fixed contact is strongly pressed. As a result, a phenomenon occurs in which the movable contact and the fixed contact are in one of right and left directions.

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

[0005] 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. A current limiting mechanism is generally used as a means for suppressing the stress. When a short-circuit current flows, the current limiting mechanism rapidly opens the movable contact prior to the normal opening operation by the tripping operation of the switching mechanism, increases the arc voltage, and performs the current limiting interruption in a short time. Things. The unlatching operation of the current limiting mechanism normally uses an electromagnetic repulsion generated by currents flowing in different directions between two parallel conductors. According to the 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 that the opening speed of the movable contact is increased as much as possible, and the generated arc is raised from the stale state to the active state in a short time to enhance the current limiting effect. However, as the size of the circuit breaker increases and the current carrying capacity increases, the mass of the movable contact increases accordingly, and as a result, the moment of inertia when the contacts are separated increases. There was a problem that it would be difficult to increase. Therefore, the present invention provides a circuit breaker that can easily increase the opening speed of the movable contact at the time of current limit interruption, even in a large-capacity circuit breaker where it has been conventionally difficult to obtain a current limiting effect. It is an object to provide a contact device.

[0007]

SUMMARY OF THE INVENTION In order to increase the contact area between a movable contact and a fixed contact, the present invention provides a flat conductor.
The two contact bodies made of
A movable contact for each phase is formed, and a movable contact is provided at one end of the movable contact.
Each contact body is divided and attached, and
The other end of the contact is energized to the connection conductor having a trifurcated contact piece
It is connected rotatably by a pin, and both ends of this energizing pin are
A contact member that slidably presses the contact piece and the contact piece;
A chin is attached (claim 1). In order to enhance the separable speed of the movable contact when current limiting cut-off, the originating
Ming according to claim 1, wherein the contact body protrudes laterally.
Of the current contact pin and the movable contact
The current limiting pin is rotatably supported by an insulating holder
A current limiting latch having a U-shaped latch surface abutting against
Inserted between the current limiting latch and the insulating holder,
A current limiting spring for pressing the current limiting latch against the current limiting pin.
A current limiting mechanism is provided (claim 2). In the movable contact device, these contact members are placed between two contact members.
Regulate the spacing of the contacts and allow these contacts to
Inserting a spacing member that is linked to the opening direction through
(Claim 3). The connection having a trifurcated contact piece
The conductors butt a pair of bifurcated conductors with different right and left
Alternatively, they may be configured together (claim 4).

[0008]

The movable contact is divided into two pieces, and the movable contact is divided and attached to each of the two contact bodies. As a result, the movable contact has a twin structure, and the point of contact with the fixed contact is twice that of the single contact. At the same time, a large contact having a large width is also divided into two parts, so that the width is reduced and the contact property is improved. In addition, since the two contact bodies are independent of each other, even when the facing distance between the movable contact and the fixed contact is different on both the left and right sides, the left and right contact bodies are vertically moved so as to be adapted to the fixed contact. And the contact body is 1
The contactability is better than when two movable contacts are simply mounted side by side on a single normal movable contact. Further, the contact portion between the movable contact and the connection conductor is formed by connecting the two contact members to the trifurcated contact piece of the connection conductor, so that the central contact piece serves as a common contact section and the contact pieces on both sides serve as common contact portions. Each contact body is sandwiched between the contact bodies, and a contact area twice as large as that when one movable contact is sandwiched between forked connection conductors can be obtained.

On the other hand, two contactors made of a flat conductor are arranged independently and in parallel with each other to form a movable contact for one phase, and a current limiting mechanism is provided for each contactor.
After reducing the mass per contact body by half, the contact bodies can be independently driven by the respective current limiting mechanisms to greatly increase the separation speed at the time of current limiting interruption. The current of each movable contact is divided into two parallel contact bodies, and an electromagnetic attraction 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 are attracted to each other and deformed, or the adjacent divided contacts come into contact and weld. Therefore, it is preferable to insert a spacing member between the contact bodies to prevent the inside of the contact body from being deformed, but this spacing member also interlocks the separating operation of the two contact bodies arranged in parallel. It is preferable that these components be connected to each other so as to make them work. However, an appropriate play is provided between the spacing member and each contact body so that each contact body can be individually driven by the electromagnetic repulsive force at the time of current limit interruption. Thereby, at the time of current limiting interruption, in a separation initial state in which the movable contact is initially driven by the electromagnetic repulsive force, each contact body operates independently of each other, and in a separating 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 three-pole circuit breaker will be described below with reference to FIGS. First, FIG. 1 is an exploded perspective view showing one phase of a movable contact device, FIG. 2 is a longitudinal sectional view thereof, FIG. 3 is a perspective view of an interval frame, and FIG. 4 is a rear view of a main part of FIG. It is. In these figures, a movable contact 1 is provided on a connection conductor 2 with an energizing pin 3 passing therethrough.
The connecting conductor 2 is fixed to the main body case 4 of the circuit breaker with screws 5. The movable contact 1 of each phase is composed of two contact members 6 stamped and formed from a copper plate.
The movable contact 7 is divided into two parts and is joined to the tip of the contact body 6 with the same width. The movable contact 7 has a contact surface formed in a front and rear arc shape, 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 member that straddles the left and right pieces of the movable contact 7, and the contact surface is entirely flat. Power supply pin 3
There proximal end portion of the contact transducer body 6 which penetrates are bulges V-shaped downward in the figure, current limiting pin 10 which serves to be described later in the vicinity of the tip is implanted, respectively so as to project laterally I have.

The connecting conductor 2 has a mountain shape as shown in the drawing, comprising a trifurcated contact piece 2a and a mounting portion 2b, and is integrally formed by punching and bending from a copper plate. Bearing bosses are formed on the left and right contact pieces 2a by burring around the holes through which the conducting pins 3 pass. Movable contact 1
And the connection conductor 2, the two contact members 6 are provided at the center contact piece 2.
a and the contact pieces 2a on the left and right sides thereof are combined so as to be sandwiched between them, and are slidably pressed against each other by contact springs 11 composed of compression coil springs mounted on both ends of the power supply pins 3. ing. Between the left and right contactor bodies 6 of the movable contactor 1, an interval frame 1 having a shape shown in FIG.
2 has been inserted. The interval top 12 is the center disk 12
a has the same thickness as the contact piece 2a at the center of the connection conductor 2, and this portion abuts on the opposing side surface of the contact body 6 to regulate the distance therebetween. 13 (FIG. 1). There is an appropriate play between the bearing hole 13 and the shaft portion 12b, and the right and left contact members 6 can move within a range vertically above and below each other.

The base end of the movable contact 1 and the connection conductor 2
The illustrated hollow insulating holder 14 made of mold resin
To be housed. The insulating holders 14 of the respective phases are connected to each other by an integrally formed opening / closing shaft 15 (FIG. 1).
And is rotatably supported by the main body case 4 via the. 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 from a steel plate.
The support shaft 1 is composed of a U-shaped back wall that constitutes a and 16b, and arms on both sides serving as bearings of the support shaft 17, and a current-limiting spring 18 composed of a compression spring inserted between the support holder 17 and the insulating holder 14.
7 is urged in the clockwise direction in FIG. The movable contact 1 and the connection conductor 2 which are connected by the energizing pin 3 are connected to the 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 to be combined with the insulating holder 14.
At this time, the right and left current limiting pins 10 projecting from the contact body 6 compress the current limiting spring 18 while the two right and left current limiting latches 16
The contact springs 11 respectively pressed by the current limiting surfaces 16a and mounted on the energizing pins 3 are compressed on the inner wall surface of the insulating holder 14.

As shown in FIG. 2, an insulating holder 14 in which the movable contact 1 is incorporated is rotatably fitted in a bearing groove formed in a not-shown phase space wall of the main body case 4, and a connecting conductor 2 is mounted. It is fixed to the main body case 4 by the screw 5 screwed into the screw hole 21 (FIG. 1) of the portion 2b from the back side of the main body case 4 as described above. The connection conductor 2 is connected to a conductor 24 integral with the load side terminal by a screw 23 passing through a hole 22 (FIG. 1). Although not shown, conductor 2
In the middle of 3, there is provided an overcurrent trip device including a bimetal 25 using the heater as a heater and an armature adsorbed on a fixed iron core surrounding the conductor 24. In the closed state of FIG. 2, the insulating holder 14 is held in an illustrated state by an opening / closing mechanism (not shown), and the movable contact 7 is pressed by the fixed contact 9. In this state, the movable contact 1 is
From the current limiting latch 16 via the current limiting latch 16,
It is urged counterclockwise to obtain a predetermined contact pressure between the contacts 7 and 9. The current limiting spring 18 is a parent-child spring in which two springs having different winding directions and diameters are concentrically combined, and generates 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 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 abutting on the latch surface 16 a is moved from the current limiting latch 16 to the current limiting spring 18.
However, since the line of action of this force passes under the axis of the energizing pin 3 in the figure, the movable contact 1 is attached counterclockwise toward the fixed contact 8 as described above. It is being rushed. Now, when a large current such as a short-circuit current flows, as shown by an arrow in FIG. 2, the movable contact 1 and the fixed contact 8 are moved by the electromagnetic repulsion between the currents flowing in opposite directions to each other. The child 1 is driven in a clockwise direction, and the contact points 7, 9 are separated. At this time, when the movable contact 1 rotates slightly clockwise, the contact of the current limiting pin 10 is changed to the latch surface 16a.
From the current limiting spring 18 to the current limiting pin 10
The line of action of the force passes through the upper side of the axis center of the energizing pin 3 in the drawing. As a result, the current limiting spring 18 for the movable contact 1
Is reversed in the clockwise direction from the counterclockwise direction, and the movable contact 1 is driven by both the electromagnetic repulsive force and the force of the current limiting spring 18 to quickly separate the contacts 7 and 9. As a result, the current limiting is performed without waiting for the drive of the insulating holder 14 by the opening / closing mechanism that is tripped by the operation of the overcurrent tripping device.

In the above configuration, the movable contact 1 is composed of two independent contact members 6, and the movable contact 7 is separately mounted on these. Therefore, the movable contact 7 has twice the number of contact points as compared with the case of a single contact, and the width of each of the movable contacts 7 is reduced to half so that familiarity with the fixed contact 9 is improved, so that a large contact area can be obtained. Further, even when the movable contact 1 tends to fall in the horizontal direction as a whole due to an assembling 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 contact members is configured. 6 moves the head up and down independently of the left and right in accordance with the fixed contact 9, and the two left and right movable contacts 7 always come into contact with the fixed contact 9. For this reason, when the movable contact 7 divided into right and left is brought into contact with the fixed contact 9, the respective contact resistance is reduced 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 is as follows. A single movable contact having a rated current carrying capacity of 800 A and one contact having a plane cross section of 10 mm × 9 mm, and a normal silver alloy contact having a flat cross section of 10 mm × 4 mm obtained by dividing the contact into approximately two parts. When the contact resistance of a movable contact having a split configuration according to the present invention was measured, the contact resistance of a single movable contact was 4
The contact resistance of the split movable contact was 37.7 μΩ on the left and 33.4 μΩ on the right. The measurement of the contact resistance was performed by setting the contact pressure to 10 kg and passing a direct current of 100 A. In this case, current I flowing through each phase flows through the I ₁ and the contact transducer body 6 of left and right branched into and I ₂ by the movable contact 7, as shown in FIG. 1, further these currents, as shown in FIG. 4 respectively contact portion between the connection conductor 2 is split into the I ₁₁ and I ₁₂ and I ₂₁ and I ₂₂ to. Therefore, the amount of heat generated at the contact portion between the movable contact 7 and the fixed contact 9 in this case is smaller in the case of the movable contact having the divided configuration than in the case of the single movable contact as described above.
Although the contact resistance between them is small, for the sake of simplicity, if the contact resistance between them is R and the current is I ₁ ≒ I ₂ ≒ I / 2,
(I / 2) ² · R + (I / 2) ² · R = (I ² R) / 2
And the heat value I ^{2 for} a single movable contact integrated left and right
It is half of R.

Similarly, the amount of heat generated at the contact portion between the movable contact 1 and the connection conductor 2 is reduced by the contact member 6 and the contact piece 2a for simplicity.
The contact resistance between r and I ₁₁ ≒ I ₁₂ ≒ I ₂₁ ≒ I ₂₂ ≒ I /
If it is 4, it is represented by (I ² r) / 4, which is half of the calorific value (I ² r) / 2 when a movable contact made of one contact body is sandwiched between forked connecting conductors. On the other hand, in FIG.
The currents I ₁ ,
Electromagnetic attraction acts between I ₂ . This electromagnetic attractive force tends to bend the contact body 6 when a short-circuit current passes, but in the illustrated embodiment, since the spacing frame 12 is inserted, the contact bodies 6 are prevented from approaching each other, and There is no danger that the movable contact 6 is deformed or the left and right movable contacts 7 come into contact with each other and weld. The movable contact 1 of each phase is composed of two contact members 6, and these contact members 6 have a play range between the shaft portion 12b of the interval frame 12 and the bearing hole 13 at the time of current limit interruption. Are driven independently of each other by electromagnetic repulsion, and then driven at high speed in conjunction with the respective current limiting springs 18 to the fully opened position as described above.

That is, the movable contact 1 has two contact members 6.
Divided into two pieces, each of which receives the electromagnetic repulsion force and the force of the current-limiting spring 18 has half the mass of a normal movable contact made of an integral conductor. The opening speed of the contact 1 increases. As a result, the time until the movable contact 1 receives the electromagnetic repulsive force and the current limiting mechanism starts operating (arc stuck time), and the movable contact 1 is fully opened by the operation of the current limiting mechanism to generate an arc. The time required to rise to the active state (rise time of the arc voltage) can be suppressed even in a large circuit breaker to the same level as a small capacity circuit breaker. 5 and 6 show an example of measuring the maximum peak current peak value and the passing I ² t at the interruption of 460 V and 65 kA for the circuit breaker of the 800 A frame. This is shown in comparison with the circuit breaker of FIG. As shown in the figure, according to the present invention, both the maximum peak value of the passing current and the passing I ² t are greatly reduced, and the thermal and mechanical stress on the case and the cover is suppressed accordingly. In order to improve the current limiting performance only, the electrical connection between the movable contact 1 and the fixed-side connection conductor does not necessarily have to be made by sliding contact as in the illustrated embodiment. Connection by a conductor is also acceptable.

FIGS. 7 and 8 show different embodiments of the connection conductor 2. FIG. 7 is a perspective view of one side, and FIG. 8 is a rear view showing a state where the connection conductor 2 is connected to the movable contact 1. FIG. In the embodiment of FIG. 1, the connecting conductor 2 is formed by bending the entirety integrally, whereas in this embodiment, the connecting conductor 2 is formed by a pair of forked conductors 2 </ b> A and 2 </ b> B having different right and left sides butted against each other to form a three-pronged shape. Is formed. The forked conductors 2A and 2B sandwich the left and right contact bodies 6 of the movable contact 1, respectively, and butted against each other. According to such a configuration, 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.

FIG. 9 is a rear view of an essential part showing an embodiment in which the contact portion between the movable contact 1 and the connection conductor 2 is made spherical.
That is, in this embodiment, a spherical convex portion is formed on the contact piece 2a of the connection conductor 2, and a spherical concave portion having a slightly larger radius of curvature is formed on the contact body 6. These uneven portions are overlapped as shown, and are slidably pressed against each other by a contact spring 11. In this case, an appropriate play is provided between the energizing pin 3 and the hole of the contact body 6 through which the energizing pin 3 penetrates. According to such a configuration, the contact body 6 can rotate with respect to the connection conductor 2 as indicated by an arrow in the figure, and the restraint of the connection conductor 2 against the left and right inclination of the contact body 6 is weak. Become. Therefore,
As described above, when the horizontal parallelism between the movable contact 7 and the fixed contact 9 is poor, the contact body 6 is
It is easy to change the inclination posture in the left-right direction in accordance with the condition, and the movable contact 7 is more easily adapted to the fixed contact 9 so that the contactability is further improved.

[0020]

As described above, according to the present invention, the movable contact is divided into two contact members, and the movable contact is separately mounted on each of the two contact members. , And a large contact having a large width is also divided into two, so that the width is reduced and the contact property is improved. In addition, since the contact bodies are left and right independent, even if the facing distance between the movable contact and the fixed contact is different on both the left and right sides, swing the head up and down so that the left and right contact bodies become familiar with the fixed contact. ,
Also in this surface, the contact property is improved. Therefore, in the case of large circuit breakers with large contact widths, when the parallelism between the contacts in the horizontal direction is poor due to assembly errors or component accuracy, etc., or when the overload current is tripped, the contact surface of the fixed contacts may bulge due to thermal damage. 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 contact to a connection conductor having a trifurcated contact piece, each contact body can be sandwiched between the contact pieces on both sides with the central contact piece as a common contact portion. Has a contact area twice as large as when one connecting conductor is sandwiched between two contact bodies or when the contact body sandwiches one movable contact between forked connecting conductors. It is possible to provide a sufficient current carrying capacity between the movable contact and the connection conductor.

Further, by providing two contactors composed of flat conductors independently and in parallel with each other to constitute a movable contact for one phase and providing a current limiting mechanism for each contactor, a current limiting mechanism is provided. The mass to be driven by the electromagnetic repulsion force and the current-limiting spring force at the time of cutoff is halved, and even in a large-capacity circuit breaker, which is considered to be difficult to achieve the current-limiting effect, the opening speed of the movable contact can be easily increased and the arc Power can be significantly reduced.
In such a movable contact device, the distance between these contact members is regulated between two contact members , and
While interlocking the contact body in the opening direction through appropriate play
By inserting a separating member, even when a large current flows, the contact
Deformation of contact body due to electromagnetic attraction and welding of split contacts
Can be effectively prevented, and the two
Independent operation in the initial state of separation when the tactile element is current-limiting
They can be linked without loss. In addition, trifurcated
A pair of bifurcated left and right connection conductors with contact pieces
Press forming is easy if the conductors are configured to abut each other.
It becomes simple and can be manufactured at low cost.

[Brief description of the 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 longitudinal sectional view of the movable contact device of FIG.

FIG. 3 is a perspective view of an interval frame in FIG. 1;

FIG. 4 is a rear view of a main part of FIG. 2;

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

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

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

8 is a rear view of a main part of a movable contact device using the connection conductor of FIG. 7;

FIG. 9 is a main part rear view showing a different embodiment of the contact surface between the movable contact and the connection conductor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Movable contact 2 Connection conductor 3 Power supply pin 4 Main body case 6 Contact body 7 Movable contact 8 Fixed contact 9 Fixed contact 10 Current limiting pin 11 Contact spring 12 Spacing frame 14 Insulating holder 15 Opening / closing axis 16 Current limiting latch 17 18 Current limiting spring

Continuation of front page (56) References JP-A-5-54786 (JP, A) JP-A-4-19938 (JP, A) JP-A-57-23429 (JP, A) JP-A-6-325678 (JP) , A) Jikgyo 13-12778 (JP, Y1) Jigyo 18-18889 (JP, Y1) Jigyo 35-11949 (JP, Y1) (58) Fields surveyed (Int. Cl. ⁷ , DB (Name) H01H 73/02

Claims (4)

(57) [Claims] 1. A movable contact for one phase is formed by independently arranging two contact members made of a flat conductor in parallel with each other, and a movable contact is divided at one end into each contact member. At the same time, the other end of the movable contact is rotatably connected to a connection conductor having a trifurcated contact piece by an energizing pin,
A movable contact device for a circuit breaker, wherein contact springs for slidably pressing the contact body and the contact piece are attached to both ends of the energizing pin. 2. The contact body is planted so as to protrude laterally.
Current limiting pin and an insulating housing for accommodating the movable contact.
And is rotatably supported by the
Current limiting latch having a U-shaped latch surface and the current limiting latch
Between the current limiting latch and the insulating holder.
Claim 1 Symbol, characterized in that a current limiting mechanism comprising a limiting spring which presses said current limiting pin for each <br/> the contactor body
The movable contact device of the circuit breaker described above. 3. A contact body between two contact bodies.
The contact distance and allow these contacts to play properly.
3. A movable contact device for a circuit breaker according to claim 2, wherein a spacing member interlocked with the opening direction is inserted through the intermediary member . 4. The connecting conductor having a trifurcated contact piece is left
Composed of a pair of bifurcated conductors with different right hand sides
2. The movable circuit breaker according to claim 1, wherein:
Contact device.