JPH0337257B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a circuit breaker or disconnector having a structure that opens instantaneously due to electromagnetic repulsion when a large current passes through it, and particularly to a circuit breaker that is designed to shorten the operating time of the breaker mechanism. It is.

Conventionally, this type of current-limiting circuit and breaker was shown in Figure 1.
It was configured as shown in Figure 2. Figure 1 shows the state of the contact when the rated current is applied (indicated by the solid line) and when a large current such as a short circuit current is applied (indicated by the broken line). Figure 2 shows the state of the contact when the instantaneous tripping element Shows the state of each part of the mechanism when it is in operation. 1 is a fixed contact whose tip is bent into a U-shape; 2 is a movable contact arranged parallel to the fixed contact 1;
3 is a fixed core wound around the main conductor, 4 is a movable core disposed opposite to the fixed core 3, 5 is a common tripping shaft driven by the movable core 4, and 6 is the common tripping shaft 5. A tripping fitting 7 is urged to engage, a toggle lever 7 is engaged with the tripping fitting 6 and is always urged counterclockwise, and 8 is a toggle lever that supports the movable contact 2 and rotates. Moving movable frame, 21
is a bimetal which is heated by the overload current of the main circuit, bends and drives the common trip shaft 5.

When a large current such as a short circuit current flows in the main circuit,
Without waiting for the operation of the tripping elements 3 and 4, the movable contact 2 rotates away from the fixed and movable contacts 1 and 2 in the direction of the arrow due to the electromagnetic repulsion force acting between the fixed and movable contacts 1 and 2. , 2 to limit the large passing current. Almost simultaneously with the start of the current limiting, the movable core 4 constituting the tripping element is attracted by the fixed core 3, causing the common tripping shaft 5 to rotate. The tripping fitting 6 is disengaged from the common tripping shaft 5, and then, by the counterclockwise urging of the toggle lever 7, the tripping fitting 6 rotates clockwise and is also removed from the toggle lever 7. . Therefore, by rotating the toggle lever 7, the movable contactor 2 is rotated via the link mechanism 10 to perform the opening operation. This opening operation opens the movable contact to the full breaking distance (maximum opening distance). Until this contact opening operation occurs, the movable contact 2 is held in the repulsion position (indicated by the broken line in Figure 1) by the electromagnetic repulsion caused by the passing large current, or by the electromagnetic repulsion according to the instantaneous value of the passing current. Due to the decrease, the passing current is limited while reciprocating between the original position, that is, the energized position, or the vicinity thereof. Therefore, the peak value of the passing current is suppressed to a low level, and the breakage after the mechanism is operated due to the operation of the tripping element is quickly completed.

FIG. 3 is a diagram showing the waveform of a current-limiting type circuit breaker equipped with an electromagnetic repulsion movable contactor. As shown in this figure, when the load current reaches the electromagnetic repulsion current, the movable contact 2 starts opening at point g, and completes opening due to electromagnetic repulsion at point h. On the other hand, the tripping element 4 starts operating in the instantaneous tripping device at point a, which is almost the same as point g, and begins to rotate clockwise. The tripping element 4 hits the common tripping shaft 5 at point b and rotates it counterclockwise. Next, the common trip shaft 5 is c
The engagement with the tripping metal fitting 6 is released at the point. The tripping fitting 6 rotates clockwise and disengages from the toggle lever 7 at point d. Therefore, the link 18 of the opening/closing mechanism 18
b, 18c starts bending at point c and completes at point d. At the same time, the movable contact 2 also starts opening at point e,
Opening is completed at point f. At this point f, the movable contact 2
opens to the full distance and completes the shearing.

However, the current limiting effect and disconnection depend largely on the electromagnetic repulsion force associated with the magnitude of the passing current, and the current limiting action and disconnection occur from the start of the tripping element operation to each member of the tripping device and tripping mechanism. The opening time is longer because it depends on the time it takes for the movable contact to open, and the first wave in the case of a three-phase short circuit is small, or the magnitude of the fault current is If the current is much smaller than the rated current, the current limiting effect will be small and it will be close to non-current limiting.
It becomes difficult to effectively limit the fault current and cause it to rupture.

There are also devices that use the electromagnetic repulsive force acting on the movable contact to perform the tripping operation, but in this case, the electromagnetic repulsive force is directly transmitted from the movable contact to the link of the opening/closing mechanism, and the link is Cross the dead center in the opposite direction to the biasing direction (or hold the link in a position beyond the dead center in advance)
Some are configured to bend the opening/closing mechanism to cause it to collapse in the opening direction, while others are configured to transmit electromagnetic repulsive force to the tripping member via the opening/closing mechanism to trip this member. .

However, in the former case, a large force (electromagnetic repulsion) is required to cause the electromagnetic repulsion to act against the urging force of the link and the inertia of the opening/closing mechanism, which includes a link with a relatively large mass, and to break the opening/closing mechanism. Therefore, the size of the movable contact increases, and even if the electromagnetic repulsion force can be increased, the tripping operation is performed against a large inertia, resulting in unstable operation. In the latter case, the tripping force is transmitted through a path different from the original tripping operation, that is, through the opening/closing mechanism, so the tripping force is applied to the tripping member from two systems, and each part of the tripping mechanism is affected. Force balance and positioning become extremely difficult, and the tripping operation becomes unstable.

The present invention provides a circuit breaker with a short current limiting start time and stable tripping operation when a fault current occurs. This is intended to speed up the electrode opening operation by transmitting the signal to subsequent members.

Examples of the present invention will be described in detail below.

A first embodiment is shown in FIGS. 4 to 12. This embodiment is an example in which the present invention is applied to a three-phase circuit and disconnector. Components that are the same as those in the conventional example are designated by the same reference numerals. 9 is 1 fixed to the mold case 30
A pair of fixed frames (only one shown) pivotally supports a handle H, a toggle lever 7, a tripping fitting 6, and a latch fitting 10, which will be described later. Latch fitting 1
0 has a pawl-like latch portion 10a at the upper end, and are arranged in pairs, with one lower end 10d connected to the connecting rod 12.
(sensor). Further, a rotating shaft 11 is coupled outwardly to another lower end 10c of the latch fitting, and a connecting member 10' is coupled to the tip of each rotating shaft so as to be parallel to the latch fitting. The connecting rod 12' (sensing section) is connected with its axis substantially aligned with the center of the connecting rod 12. 10
b is a locking portion on which a biasing spring, which will be described later, is applied to bias the latch fitting 10. Each part 1 as a whole
0, 10', 11, 12, and 12' are connected in a crank shape to form a trip portion 20, as shown in FIG.

The latch fitting 10 is an extension end 1 of its rotating shaft 11.
1a is rotatably supported in a hole 11' of the fixed frame 9. The latch fitting 10 is arranged in an intermediate phase between the fixed frame 9 and the partition wall 32 of the molded case (FIGS. 7 and 8).
The rotating shaft 11 connected to the partition wall 32 extends to both adjacent sides through a notch 32a provided in the partition wall 32, and a connecting member 10' and a connecting rod 12' connected thereto are arranged in each adjacent side. The notch 32a is a groove 3 that extends upward from the case.
2b, and after passing the rotating shaft 11 through the groove 32b, an insulating plate 32c is inserted into the groove 32b.

The trip portion 20 is connected to the insulating partition wall 3 as described above.
Since the rotary shaft 11 is disposed straddling the phases separated by 2, at least the rotating shaft 11 straddling the phases is made of an insulating material in order to prevent a short circuit between the phases.

As shown in FIGS. 6 and 8, the tripping fitting 6 is formed partially into a box shape, and an obliquely long hole 15 is provided in the opposing sides 6a. A hole 14 for pivotally supporting the tripping metal fitting 6 is provided in the fixed frame 9 in an inclined manner. The tripping fitting 6 is arranged so that the elongated holes 14 and 15 intersect, and both holes 1
4 and 15 are connected, and the central shaft 13 is rotatably supported by the fixed frame 9 in a fitted state. A torsion spring 16 is wound around the central shaft 13, and one end of this torsion spring 16 is attached to one side 6 of the tripping fitting 6.
c, and the other end is locked to the locking portion 5b of the common tripping shaft 5, thereby biasing both the tripping fitting 6 and the common tripping shaft 5 clockwise to rotate the central shaft 13. Force downward.

Reference numeral 17 denotes a biasing spring stretched between the locking portion 10b of the latch fitting 10 and the center shaft 13;
is biased clockwise around the shaft 11, and the central shaft 13 is biased downward to position it at the lower end of the elongated hole 14. Due to the above-mentioned bias, the latch fitting 10 engages the pawl-shaped latch portion 10a with the central shaft 13, thereby preventing the central shaft 13 from moving upward.

The connecting rods 12, 12' of the trip portion 20 are connected to the fourth
It is always disposed below the rear end 2a so as to be located within the range of rotation of the rear end 2a when the movable contactor 2 is centered around the rotation axis 2d in the state shown in FIGS.
Further, when the trip portion 20 is biased by the biasing spring 17, its connecting rod 12 is engaged with the lower end of the fixed frame 9, and this lower end serves as a stopper. Further, it is desirable that the mass of the trip portion 20 is set smaller than the mass of the movable contact alone.

The tripping fitting 6 and the common tripping shaft 5 constitute a tripping mechanism, and the instantaneous tripping elements 3 and 4 and the bimetal 21
constitutes an overcurrent response device. The tripping mechanism has three engaging parts. That is, the engagement portion between the overcurrent response device 4, 21 and the common tripping shaft 5,
The protrusion 5a of the common trip shaft 5 and the tip 6 of the trip metal fitting
b, and the engaging portion between the tripping metal fitting 6 and the lever 7.

The trip portion 20 is arranged so as to communicate with the last stage of the engaging portions that is closest to the lever 7.

As shown in FIGS. 4 and 5, when the contact is closed, the lever 7 is pressed against the spring 18a of the opening/closing mechanism 18
is biased counterclockwise. The left end of the tripping fitting 6 therefore tends to be lifted, and this force is transmitted via the central shaft 13 to the pawl-like latch portion 10a of the latch fitting. The line of action acting on the central shaft 13 and the pawl-like latch portion 10a (indicated by arrows in FIG. 10) is configured to pass near the center of the rotating shaft 11 of the latch fitting 10 or on the left side of the rotating shaft 11.

Next, the operation will be explained.

When the rated current is applied, the toggle links 18b and 18c of the opening/closing mechanism 18 become linear as shown in FIGS. 4 and 5, and the lever 7 is biased counterclockwise by the spring 18a via the links. ing. This biasing force is transmitted to the tripping metal fitting 6 and attempts to rotate it clockwise about the central shaft 13 as a fulcrum. At the same time, this biasing force is also applied to the central shaft 13,
An attempt is made to lift this shaft 13 upward. However, the latch fitting 10 is engaged with the central shaft 13,
Upward movement is blocked. On the other hand, the tongue portion 6b of the tripping metal fitting 6 is locked to the locking portion 5a of the common tripping shaft to prevent rotation.

When the main circuit current is in an overcurrent region that does not reach the electromagnetic repulsion of the movable contactor 2, the motion of the bimetal 21 or the movable core 4 causes a known tripping mechanism, that is, a common tripping shaft 5 and tripping metal fitting. 6 is released to trip and drive the opening/closing mechanism.

In the above region, the tripping fitting 6 is supported by a central shaft 13 which is fixedly supported below the elongated hole 14 by a latch fitting 10. central axis 13
Since the direction of the line of action (normal line) of the claw-like latch portion 10a when it is locked is located near the rotating shaft 11 of the latch fitting 10 or on the left side of the rotating shaft 11, as described above, ( (See FIG. 10), the latch fitting 10 does not rotate counterclockwise due to the bias transmitted from the lever 7 and does not slip off from the central shaft 13. Therefore, springs 2c, 18a
Even if the spring pressure changes, the latch fitting 10 and the center shaft 1
3 can be stably engaged with.

When the main circuit current reaches a large current region such as a short circuit current, the movable contact 2 instantaneously rotates as shown in FIG. 11 due to electromagnetic repulsion. At this time, it is assumed that the movable contactor 2 is in the intermediate phase (the phase with the fixed frame 9). As the movable contactor rotates, its rear end 2a presses downwardly the connecting rod 12 (sensing section) that was previously in contact with the fixed frame 9. This pressing causes the latch fitting 10 to rotate counterclockwise in the figure about the rotating shaft 11. The pawl-like latch portion 10a is disengaged from the center shaft 13 from the state shown in FIG. 9a as shown in FIG. 9b. Lever 7
The central axis 13 of the tripping fitting 6 is
moves upward and to the right along a long hole 14 provided in the fixed frame 9. As the lever 7 moves to the upper right of the release metal fitting 6, the engagement area with the removal metal fitting 6 gradually becomes smaller, and the lever 7 finally comes off and moves upward. In this way, the movement of the latch fitting 10 is transmitted to the lever 7 via the tripping fitting 6 in the direction in which a normal tripping movement is transmitted. The rotation of the lever 7 at this time is carried out instantaneously and continuously from the start. The opening/closing mechanism 18 starts an opening operation when the link is bent.

In connection with this, the movable contact is driven to the full or breaking distance. The above operation can be seen in Figure 3 as follows. Assuming that the movable contact 2 starts opening at point g due to electromagnetic repulsion and completes at point h, the latch fitting 10 is driven by the rear end 2a of the movable contact 2,
The latch portion 10a is disengaged from the central axis 13 at the latest at point h. The movable contactor 2 is completely disconnected after the delay of the operation of the opening/closing mechanism 18 from point h, and is completely disconnected near point f'. This complete cutting is performed without including the delay time in the operation of the conventional movable core 4 and common tripping shaft 5. Therefore, after the movable contactor 2 is opened due to electromagnetic repulsion, it is immediately opened to the full or breaking distance by the opening/closing mechanism. Since it usually takes 1 msec or less from the generation of the short-circuit current until the movable contactor 2 opens due to electromagnetic repulsion, it takes about 3 to 5 msec until the first phase is completely disconnected. Furthermore, since this operation is performed via the dedicated trip section 20, it is stable and has extremely high operational reliability.

When a movable contact other than the intermediate phase first causes electromagnetic repulsion, this movable contact causes the connecting rod 1 to
2' (sensing section) will be pressed. Therefore, in this embodiment, since the two-latch metal fitting 10 can be rotated in response to the first peak current in the two-phase main circuit, the time from the start of occurrence of a fault current to its detection is shortened. In addition, in the conventional structure, the movable contacts of each phase individually limit the current by electromagnetic repulsion according to the passing current, so there were some phases where the current was not sufficiently limited, but in this embodiment, three Due to the electromagnetic repulsion of the phase that repulses the fastest and has the largest repulsive force, the movable contacts of all phases open at the same time. In order to quickly complete the shear cutting process and move on to the simple single phase two-point cutting process,
It takes less time to complete a short circuit or disconnection, and the passing current can be kept much lower than before. According to actual measurements, when a three-phase short circuit is the starting point, the completion of opening due to electromagnetic repulsion of the movable contact is less than 1 msec, the release of lever 7 is 3 msec, the start of the link (opening/closing mechanism) trip is 4 msec, and the first phase Total length 5m
It becomes around s, transitions to single-phase shearing, and the second and third
It takes 7 to 10 msec to complete or disconnect (AC460V,
30KA (when disconnected). Conventional full-stop time is 10 to 14
It is msec.

The reset operation is performed as follows. After the tripping operation, the lever 7 is moved to the tripping bracket 6 as shown in Fig. 2.
It is removed from the body and lifted upwards. If you move the handle H to the right from this state, lever 7
rotates clockwise around the pivot shaft 7a with the fixed frame 9. The tip of the lever 7 hits the upper surface of the tip of the tripping metal fitting 6 as shown in FIG. 12a, and the tripping metal fitting 6 is pushed down. At this time, the pawl-like latch 10a of the latch fitting returns to its original position by the spring 17, so that it is located below the central shaft 13.

The center shaft 13 is positioned at the lower end of the elongated hole 15 by a spring 16.

The tripping metal fitting 6 is gradually pushed as shown in FIG.
It rotates around the locking point with the common trip shaft 5. The tripping fitting 6 moves along the central axis 13 within the movement range of the elongated hole 15. At the same time, the central shaft 13 pushes down the upper end of the pawl-like latch portion 10a of the latch fitting. This latch portion 10a is pressed against its upper surface which is sloped downward to the right, so that it is pressed to the left as shown by the arrow in FIG. The central shaft 13 is connected to this latch portion 10a.
When lowered, the latch fitting 10 is always urged to the right in FIG. Lock as shown in Figure c. On the other hand, the lever 7 is connected to the tripping metal fitting 6 in Fig. 12b.
Lower it while pushing it to the right as shown, and remove the tripping bracket 6.
When it goes lower, it will disengage from the top surface of the tripping fitting. When the tripping fitting 6 is disengaged from the lever 7, the spring 16 causes it to rotate slightly clockwise around the engagement point with the common tripping shaft 5 and shift to the left.

At the same time, the center shaft 13 is moved to the lower right in the figure so that it comes to the lower end of the elongated hole 15. When the handle is released in this state, the lever 7 attempts to rotate counterclockwise. Therefore, the lever 7 is locked to the tripping metal fitting 6 as shown in FIG. 12c.

In the above embodiment, since the trip portion is arranged along the inner surface of the partition wall 32 of the molded case, the trip portion occupies a small space and can be easily applied to ready-made circuits and disconnectors.

Further, in the above embodiment, the trip portion 20 is connected to the shaft 13.
Although the trip portion 20 is connected to the trip fitting 6 via the lever 7, the trip portion 20 may be directly connected to the trip fitting 6, and the trip portion 20 acts directly on the engagement point between the lever 7 and the trip fitting 6. You may contact us as follows. Furthermore, depending on the case structure of the circuit or disconnector, the trip portion 20 may be connected to disconnect the engaging portion closer to the overcurrent response device than in the above case, and in this case, more connections than in the above embodiments may be made. Although the movement of the trip portion is transmitted to the opening/closing mechanism via the engaging portion, it is certain that the opening/closing operation can be performed in a shorter time than in the conventional example. However, an engagement portion configured to be tripped with a time delay such as the overcurrent response devices 4 and 21, that is, an engagement portion configured to be tripped with a time delay, that is, an engagement portion between the overcurrent response device and the common tripping shaft may be disengaged. Please avoid contacting the Trip Department.

Normally, the first engagement part of a tripping mechanism is an engagement with a tripping element in a long (short) time period or an instantaneous period, which starts operation with a time delay after the occurrence of an overcurrent such as this type of short circuit head. It has become a department. Therefore, the trip portion 20 according to the present invention has an n
When the trip part includes a (n-1)th or lower engaging part, the trip part moves from the circuit or disconnection opening/closing mechanism to the (n-1)th or lower engaging part, avoiding the engaging part. should be structured to convey the following.

Also, the trip part is designed to be easily driven by the movable contact, and so that the movable contact can move together with the trip part without rebounding from the trip part after colliding with the trip part due to electromagnetic repulsion. ,
It is better to make the mass smaller than that of the movable contact alone. Furthermore, this embodiment can naturally be applied to single-phase circuits and disconnectors.

FIG. 13 shows a second embodiment. The same parts as in the first embodiment are denoted by the same reference numerals. In this embodiment, a spring 17a is stretched between the bottom of the mold case 30 and the bottom of the latch 101 as a biasing spring for the latch 101. Furthermore, the central axis 13
A spring 17a is stretched between the fixed frame 9 and the fixed frame 9. Furthermore, a spring 17b is stretched between the central shaft 13 and the fixed frame 9, and the central shaft 13 is connected to the elongated hole 14,
15 is under consideration. springs 17a and 17b
is composed of two pieces so as to perform the function of the spring 17 of the first embodiment. In this case, the number of springs increases, but the installation space for the springs on the side of the latch fitting 10 as in the first embodiment is not required, and the width dimension of the intermediate phase in which the fixed frame 9 and the latch fitting 101 are housed can be reduced. .

A third embodiment and a fourth embodiment are shown in FIGS. 14 and 15. A heart-shaped hole 22 is provided at the tip of each of the latch fittings 102 and 103, and the central shaft 13 is fitted into this hole 22. The latch fittings 102 and 103 are pivotally supported by the rotating shaft 11,
They are biased clockwise by springs 17e and 17f, respectively. The central axis 13 is biased toward the bottom of the hole 22 by springs 17d and 17g. If the inner surface 22a of the hole 22, which is approximately in the center, is inclined,
Due to the clockwise bias of the latch fittings 102, 103, this inclined surface 22a pushes down the central shaft 13, so the springs 17d, 17g are no longer necessary.
Since the center shaft 13 is pushed down, the spring 17
d and 17g become unnecessary. When the contactor is closed, the central shaft 13 is located at the lower bulge 22b of the hole 22 as shown in FIGS. When moved, it moves to the upper bulge 22c of the hole 22, and accordingly, similarly to the first embodiment, the tripping fitting 6 (not shown) is moved upward to drive the opening/closing mechanism.

In all of the above embodiments, the center shaft 13 is always engaged with the latch fittings 102, 103, so even after the tripping operation, the center shaft 13 is quickly moved by the clockwise urging force on the latch fittings 102, 103. It returns to its original position, making the reset operation easier.

FIG. 16 shows a fifth embodiment. Reference numeral 104 denotes a latch fitting that is integrated with the central shaft 131 and rotates around this shaft. The central shaft 131 has a semicircular cross section, is rotatably supported by the tripping metal fitting 61, and is engaged with the lever 7. The tripping fitting 61 is pivotally supported by a shaft 62 on a fixed frame (not shown), and biased clockwise by a spring 63 wound around the shaft 62. The spring 63 has one end locked onto the common trip shaft 5 and biases the shaft 5 clockwise. A spring 64 is wound around the center shaft 131, and one end of the spring 64 is engaged with the shaft 62 and the other end is engaged with the latch fitting 104, thereby constantly biasing the latch fitting 104 in a clockwise direction.

To explain the operation, when the movable contact 2 is rotated by electromagnetic repulsion, the connecting rod 12 is pushed down by the rear end 2a, and the latch fitting 104 is rotated counterclockwise. The central shaft 131 also rotates counterclockwise, and its semicircular portion (indicated by the inclined line in FIG. 16)
and the lever 7 is disengaged. Thereafter, the lever 7 is raised to drive the opening/closing mechanism in the same manner as in the first embodiment. When a tripping operation is caused by rotation of the common tripping shaft 5, the tripping metal fitting 61 is disengaged from the locking portion 5a of the common tripping shaft 5 and rotates clockwise about the shaft 62. Therefore, the central shaft 131 moves to the right in the figure and is removed from the lever 7. Then lever 7
rises and the opening/closing mechanism is driven. In this embodiment, since the rotational moment of the latch fitting 104 caused by the movable contact 2 becomes large, the lever 7 and the center shaft 1
Even if there are large variations in engagement with 31, the tripping operation can be performed stably. Furthermore, the trip portion, that is, the latch metal fitting 104 is directly attached to the lever 7.
Since the lever 7 is configured to be involved in the engagement of the lever 7, the operation of the trip portion can be transmitted to the lever 7 more directly. In addition, the number of parts is small and the space occupied is small.

FIG. 17 shows a sixth embodiment. Reference numeral 105 denotes a latch metal fitting that is pivotally supported by a fixed frame (not shown) via the rotating shaft 11, and has a substantially L-shaped tip extending upward. Reference numeral 64 denotes a tripping metal fitting 106 which is pivotally supported on a fixed frame (not shown) via a shaft 66.
is a latch metal fitting that is pivotally supported by the tripping metal fitting 64 via the center shaft 132, and the lower part is the latch metal fitting 1.
It is placed opposite to 05. Latch fitting 106 is fixedly coupled to central shaft 132. A spring 65 is wound around the shaft 66, and one end of the spring 65 is engaged with the common tripping shaft 5 to bias it clockwise, and the other end is engaged with the latch fitting 106 so that the spring 65 is pulled through the latch fitting 106. Push the removal fitting 64 clockwise. Similar to the fifth embodiment, the central axis 132 has a semicircular cross section,
A lever 7 is locked to this portion. The latch fitting 105 is biased counterclockwise by a spring 17b.

To explain the operation, when the movable contact 2 rotates due to electromagnetic repulsion, its rear end 2a engages the connecting rod 1.
2 is pressed down to rotate the latch fitting 105 clockwise. The tip of the latch fitting 105 moves to the right and pushes the lower end of the latch fitting 106 in the direction of the arrow. Therefore, the central shaft 132 rotates clockwise,
The semicircular portion and the lever 7 are disengaged. In the subsequent operation, the lever 7 is raised and the opening/closing mechanism is driven in the same manner as in the first embodiment. When a tripping operation is caused by rotation of the common tripping shaft 5, the tripping metal fitting 64 rotates around the shaft 66 to disconnect the central shaft 132 and the lever 7, as in the fifth embodiment. .

In this embodiment, the latch fitting 104 of the fifth embodiment is divided into two parts, and the latch fittings 105 and 106 are constructed.
Even if there is some error in the positional relationship of 106, it can be absorbed. In addition, during the reset operation, the lever 8 moves toward the semicircular portion (the 17th
Press the flat part (shown with diagonal lines in the figure), and
32 in the counterclockwise direction. At this time, only one side 106 of the latch metal fittings needs to be rotated, so a small force is required, and the reset operation is easy.

FIG. 18 shows a seventh embodiment. Reference numeral 107 denotes a latch fitting that is pivotally supported on a fixed frame (not shown) via the rotating shaft 11;
71 is a lever connected to the links 18a and 18b, and 72 is a lever pivotally supported on the lever 71 by a shaft 73. The lever 72 has an elongated hole 74 into which a pin 75 is fitted so as to be movable, and this pin 75 is urged upward by a spring 76. The lever 71 is rotated counterclockwise about a shaft 77 by a biasing spring (not shown) 18a. The lever 71 is engaged with a shaft 73 and a pin 75, and transmits the counterclockwise rotational force to the lever 72 via these. One end of the latch fitting 107 is disposed corresponding to the rear end 2a of the movable contact, and the other end is arranged to correspond to the rear end 2a of the movable contact.
It is fixed on the top surface of 5. The latch fitting 107 presses the pin 75 with a pressure that does not push the pin 75 down by a spring (not shown).

To explain the operation, the rotation of the movable contact due to electromagnetic repulsion forces the rear end 2a to push down the lower end 107a of the latch fitting. Latch fitting 10
7 rotates counterclockwise around the shaft 11. The upper end 107b of the latch fitting 107 is connected to the pin 75 in the elongated hole 7.
Move it downward along 4. Therefore, the pin 75 and the lever 71 are disengaged, and the levers 71 and 72 are bent around the shaft 73 by the biasing force.
It has a pyramid shape with the axis 73 as the apex. The lever 71 pulls the lever 72 to the left while rotating the shaft 77.
Rotates counterclockwise around the center to drive the opening/closing mechanism.

In this embodiment, the lever connected to the opening/closing mechanism consists of two members and is configured to be bent.

As is clear from the above description, the present invention utilizes the trip portion to disengage the engagement portion of the disengagement mechanism by redirecting the movement of the movable contactor which rotates due to the electromagnetic repulsion force that acts instantaneously when an overcurrent occurs due to a short circuit or the like. Moreover, since the above-mentioned movement is transmitted to the opening/closing mechanism through as few engaging parts as possible in the tripping mechanism, the current limiting operation as a whole is immediately followed by the initial current limiting operation due to electromagnetic repulsion. The tripping operation can be completed and the movable contact can be completely disconnected. Therefore, it is possible to suppress the amount of arc energy generated between the contacts to an extremely low level compared to the conventional method, which greatly contributes to improving the performance and making the circuit breakers more compact.

According to the present invention, it is possible to obtain a circuit breaker or breaker that has a short current limiting start time when a fault current occurs and has a stable tripping operation.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of the conventional structure, Fig. 2 is a longitudinal cross-sectional view when the contact is opened, Fig. 3 is a diagram showing the change in current (voltage) when the movable contact is opened, and Fig. 4 is a diagram showing the change in current (voltage) when the movable contact is opened. FIG. 5 is a longitudinal sectional view of the first embodiment of the present invention, similarly seen from a different section, FIG. 6 is an exploded perspective view of the main parts, and FIG. 7 is the same trip section. FIG. 8 is a partial plan view showing the engagement relationship between the tripping fitting and the trip portion, and FIG. 9 is a cross-sectional view of FIG.
The figure is also a side view showing the operating process of the trip part.
Fig. 10 is a side view showing the engaged state of the trip part and the trip mechanism, Fig. 11 is a side view of the main parts when the contact is repulsed and separated, and Fig. 12 is the operation process during reset. Side view showing 1st
3 is a longitudinal sectional view of the second embodiment, FIG. 14 is a side view showing a part of the trip part of the third embodiment, and FIG. 15 is a side view showing part of the trip part of the fourth embodiment.
FIG. 16 is a side view showing the main parts of the fifth embodiment, FIG. 17 is a longitudinal sectional view showing the main parts of the sixth embodiment, and FIG.
FIG. 8 is a side view showing the main parts of the seventh embodiment. 1, 2: Contactor, 3, 4, 21: Overcurrent response device, 5, 6: Tripping mechanism, 18: Opening/closing mechanism, 2
0: Trip part, 12: Sensing part.

Claims (1)

[Scope of Claims] 1. A pair of contacts that can be moved toward and away from each other, an opening/closing mechanism including a toggle link for opening and closing the contacts, and an opening/closing mechanism including n engaging portions to perform the releasing operation as described above. A circuit breaker is equipped with a tripping mechanism that transmits information to the opening/closing mechanism and drives the opening/closing mechanism, and an overcurrent response device that releases the tripping mechanism in response to a current exceeding a predetermined value. In response to the electromagnetic repulsion of the contact when energized, the (n-1)th or lower engaging parts of the tripping mechanism from the opening/closing mechanism toward the overcurrent response device are subjected to normal repulsion. A circuit breaker comprising a trip portion that transmits the electromagnetic repulsive motion in the direction in which the tripping motion is transmitted to release the engagement. 2. A plurality of pairs of the contacts are arranged corresponding to the number of phases, and the trip part has a sensing part arranged for each phase to receive movement due to electromagnetic repulsion of the contacts of each phase. The circuit breaker described in paragraph 1. 3. The circuit breaker according to claim 2, wherein the trip portion is electrically insulated between different phases.