JPS6237837A - Circuit breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] 〔Technical field〕 This invention relates to a circuit breaker.

[Background technology]

A movable contact and a mature are pivotally supported on a contact holder having a yoke, and a reversing spring is provided between the two, and by attracting the armature to the yoke in the event of a short circuit, the reversing spring is reversed and the movable contact is A method that opens the pole has been proposed.

In this circuit breaker, when a short circuit occurs, the movable contact opens due to the electromagnetic repulsion between the movable contact and the fixed contact as well as the reversal action of the reversal spring, so that the opening speed can be increased with a simple configuration. However, there was a drawback that the opening distance of the movable contact was small.

[Purpose of the invention]

An object of the present invention is to provide a circuit breaker that can increase the opening distance of a movable contact.

[Disclosure of the invention]

The present invention includes a contact holder having a yoke, an armature supported pivotally by the contact holder and facing the yoke, and a movable contact provided at a distal end, the proximal end of which rotates in the direction of rotation of the distal end. A movable contact is pivotally supported by the contact holder by a sliding shaft support that can move in parallel directions, and a fixed contact facing the movable contact is arranged parallel to the movable contact so as to generate an electromagnetic repulsion force. An abnormal current flows through the arranged fixed contact, the electric circuit section connected to the movable contact and passing through between the yoke and the armature, and the electric circuit section installed between the armature and the movable contact. a reversing spring that reverses and opens the movable contact by attracting the armature to the yoke; an auxiliary spring that causes the base end of the movable contact in an on state to approach the fixed contact; and the contact The device includes an opening/closing means for driving the child holder to open/close the movable contact.

According to this invention, the base end of the movable contact is pivotally supported by the slide shaft support so that it can move in a direction parallel to the rotating direction of the tip of the movable contact, and the movable contact is supported by the auxiliary spring. By bringing the base end closer to the fixed contact in the on state, the movable contact is placed close to the fixed contact in the on state, but when an abnormal current occurs, the armature is attracted to the yoke and the reversal spring At the same time, the base end of the movable contact is pushed away from the fixed contact by the electromagnetic repulsive force of the movable contact and the fixed contact against the auxiliary spring, and as a result, the sliding movement of the slide shaft support causes the base end of the movable contact to be pushed away from the fixed contact. The opening distance of the movable contact increases.

Embodiment A first embodiment of the present invention will be described with reference to FIGS. 1 to 4. That is, this circuit breaker includes a contact holder 2 having a yoke, an armature 3 that is pivotally supported by the contact holder 2 and faces the yoke 1, and a base end with a movable contact 6 at the distal end. 4 has a movable contact 7 pivotally supported on the contact holder 2 by a slide shaft support 5 that can move in a direction parallel to the rotating direction of the tip, and a fixed contact 8 facing the movable contact 6. a fixed contact 9 arranged in parallel to generate an electromagnetic repulsion force; The electric circuit section 10 is installed between the contacts 7.
A reversing spring 1) that attracts the armature 3 to the yoke 1 with a short circuit current flowing through the yoke 1 and reverses the movable contact 7 to open the movable contact 7; The movable contactor 7 is provided with an auxiliary spring 12 that urges the movable contactor 7 toward the 9 side, and an opening/closing means 27 that drives the contactor holder 2 to open and close the movable contactor 7 .

In the above configuration, the yoke 1 is integrally formed by forming the U-shaped contact holder 2 from a magnetic material. Further, the armature 3 faces the upper end surface 1a of the yoke 1, and support pieces 3a provided on both sides thereof are pivotally supported by a fixed shaft 13. A recess 14 is cut out in the support piece 3a, and a compressed reversal spring 1) The recess 14 is rotatably locked to the fixed shaft 13 by the extension force. The slide shaft support 5 is formed by providing a movable shaft 15 on a contact pad 7a provided on a movable contact 7, and forming a guide portion 16 in the form of a long hole in the contact holder 2. This guide part 16 has a distal end part of the movable contact 7 parallel to the direction of rotation, but can slide in the direction of rotation of the contact pad 7a with the fixed contact 8 as the center of rotation.
It has a length that allows the arc contact to move (roll) from 0.21 to 18.19 comrade contact to 18.19 comrade contact. The reversing spring 1) is installed in a compressed state between the contact pad 7a and the tip of the armature 3, and the reversing dead point of reversing the movable contact 7 of the reversing spring 1) is the center of rotation of the slide shaft support 5. This is the movable shaft 15. The auxiliary spring 12 may have enough force to bring the base end 4 of the movable contact 7 in the on state close to the fixed contact 9; It is interposed on the connecting side of the stopper 7a and the reversing spring 1) of the armature 3. The movable contact 6 and the fixed contact 8 each consist of a high melting point arc contact 18.19 and a low resistance main contact 20.21.
9 and a main contact 20.21 are provided in parallel in the direction connecting the base end 4 and the distal end of the movable contact 7, and the main contact 20.21 is located on the base end 4 side. .

Furthermore, the main contact 21 is formed with an inclination such that the adjacent side is lower with respect to the arc contact 19. Electric circuit section 1
0 is composed of a part of the base end 4 of the movable contact 7 and a flexible electric wire.

In the circuit breaker, 22 is the device stand, 23 is the cover, 2
4 is a power supply side terminal, 25 is a load side terminal, and 26 is an arc extinguishing device.

The opening/closing means 27 will be explained. That is, the fixed shaft 13 is fixed to the frame 28, the contact holder 2 is rotatably supported by the fixed shaft 13, and the return spring 29 is interposed between the bottom of the frame 28 and the contact holder 2. The contact holder 2 is biased in the direction in which the movable contact 7 is opened. A handle 31, which is partially exposed from the cover 23, is supported by a fixed shaft 30 at the upper end of the frame 28, and a tripping member 33 is supported by a fixed shaft 32 of the frame 28, and a return spring (not shown) is supported at the upper end of the frame 28. ) is biased to rotate clockwise. One end of the link 35 is connected to the movable shaft 34 of the handle 31, the other end of the link 35 is connected to one end of the trip lever 36 by the common shaft 37, and the latch portion 36a at the other end of the trip lever 36 with contact pressure spring 36b is tripped. It is locked to the hook portion 33a of the member 33. The common shaft 37 is slidably supported in a slit 38 formed in the frame 28. Further, a slit 39 is formed in the frame 28 at the middle part of the trip lever 36, and the movable frame 40 is slidably passed through the slit 39.
The trip lever 36 and the return spring 2 with the movable frame 40 in between
9, the upper end of the contactor holder 2 comes into contact. An overcurrent detection bimetal 41 faces the tripping member 33, and its curved motion causes the tripping member 33 to trip. Here, the electric path inside the circuit breaker is viewed in one direction,
Load side terminal 25. Bimetal 41. Electric circuit section 10° movable contact 7. Movable contact 6. Fixed contact 8. This becomes the fixed contact 9 and the power supply side terminal 24.

FIG. 2 shows the circuit breaker in the on state.

That is, due to the action of the reversing spring 1), the armature 3 is separated from the contact holder 2, which is a yoke, and the movable contact 7
is biased counterclockwise to apply contact pressure that presses the movable contact 6 against the fixed contact 8.

Further, since the base end 4 of the movable contact 7 is urged toward the fixed contact 9 by the auxiliary spring 12, the movable shaft 15 of the slide shaft support 5 is located at the lower end of the elongated hole 16. the result,
The main contacts 20 and 21 of the movable contact 6 and the fixed contact 8 are in contact with each other, and the arc contacts 18 and 19 are separated from each other.

In the closing process leading to this ON state, the movable contact 7 is tilted with respect to the fixed contact 9 due to the reversal spring 1) as shown in FIG. 4 ia), so the arc contacts 18 and 19 come into contact first. Then, due to the rotation of the contact holder 2 after the arc contacts 18 and 19 make contact (overtravel: OT), contact pressure is applied by the reversing spring 1) and the contact pressure spring 36b, as shown in FIG. 4(b). Main contact 20.2 as in
One comrade makes contact.

FIG. 3 shows the operating process during a short circuit. That is, the electric circuit section 1
When a short circuit current flows through the contactor holder 2, magnetic flux is generated in the contactor holder 2 that constitutes the yoke, causing the armature 3 to
suction to. At the same time, the base end 4 side of the movable contact 7 rotates counterclockwise against the auxiliary spring 12 due to the electromagnetic repulsion between the movable contact 7 and the fixed contact 9. First, due to the latter operation, the movable shaft 15 of the slide shaft support 5 moves above the elongated hole 16, so that the contact between the main contacts 20 and 21 changes to the contact between the arc contacts 18 and 19, and the movable shaft 15 increases in length. By moving to the upper side of the hole 16, the inversion position of the inversion spring 1) arrives earlier than the inversion position in the state shown in FIG. 2, so that the inversion timing becomes earlier and the opening speed becomes faster. Further, the opening force for opening the movable contactor 7 after reversal becomes larger, and the opening separation distance becomes larger.

The reset after the reversal is performed by the tip of the movable contact 7 colliding with the protrusion 26b of the arc running plate 26a of the arc extinguishing device 26 during the opening operation of the contact holder 2, which will be described later.

On the other hand, the handle 31 of the opening/closing means 27 is in the state shown in FIG.
1 to the opposite side (clockwise), the link 35 is pulled up by the movable shaft 34 and the common shaft 37 moves upward through the slit 38, so the trip link 36 rotates clockwise while being locked to the hook 33a. Then, the contact holder 2 is rotated about the fixed shaft 13 by the return spring 29 via the movable frame 40, and the movable contact 7 is separated from the fixed contact 9 and turned off. Furthermore, when a current equal to or higher than the overcurrent flows through the on-state electrical circuit, the bimetal 41 bends and rotates the tripping member 33 counterclockwise, so that the hook portion 33a is connected to the trip lever 36.
from the latch portion 36a. As a result, the return spring 29
As a result, the trip lever 36 is pushed up via the movable frame 40, and the contact holder 2 is rotated to be tripped off. Note that the trip lever 36 is reset by being pushed down by the reset protrusion 31a of the handle 31 when the handle 31 is turned to the off side, and is locked to the hook portion 33a in the returned state.

In this way, in this circuit breaker, the base end 4 of the movable contact 7 is pivotally supported by the slide shaft support 5, and the base end 4 of the movable contact 7 is moved toward the fixed contact 9 by the auxiliary spring 12. Because of the energization, in the on state, the movable contact 7 approaches the fixed contact 9 and is susceptible to electromagnetic repulsion in the event of a short circuit, but in the event of a short circuit, the base end 4 of the movable contact 7 is
Since the shaft 15 of the slide shaft support 5 moves so as to separate it from the fixed contact 9, the reversal timing at the time of a short circuit can be made earlier, the opening force can be increased, and the opening distance can be increased.

In addition, the movable contact 6 and the fixed contact 8 are connected to the main contact 20.2.
1 and arc contacts 18 and 19, it is possible to first insert and then break, and it is possible to prevent the main contacts 20 and 21 from lifting up, thereby ensuring the welding resistance of the contacts and the stability of contact resistance.

Furthermore, since the main contact 21 is inclined, the movement of the contact from the arc contact 18° 19 to the main contact 20, 21 and vice versa due to the rotation of the movable contact 7 is small. 7's OT amount is small.

As a modification of this embodiment, in FIG. 5, the movable contact 6 and the fixed contact 8 are formed in a flat shape without any inclination.

In this case, the OT amount increases, but other effects are the same as in the previous embodiment. A second embodiment of the invention is shown in FIGS. 6 and 7. That is, in this embodiment, the movable shaft 15 of the slide shaft support 5 that pivotally supports the base end 4 of the movable contact 7 is provided on the contact holder 2, and the guide portion 16 is formed on the contact pad 7a. be. In this embodiment, since the guide part 6 moves around the movable shaft 15 by the auxiliary spring 12, in the on state the movable shaft 15 is located above the guide part 16 as shown in FIG. On the contrary, the movable shaft 15 is located at the lower end side of the elongated hole 16 as shown in FIG.

Therefore, in this embodiment, as in the first embodiment, the amount of opening of the movable contactor 7 at the time of a short circuit can be increased.

In the present invention, the opening/closing means 27 includes one without a trip mechanism, and may be one that reciprocates instead of rotating. Furthermore, although the embodiment deals with short-circuit current, it may be of any type as long as it responds with abnormal current such as overcurrent. Further, although the auxiliary spring 12 is interposed between the armature 3 and the contact stopper 7a of the movable contact 7, it may be necessary to bias the base end 4 of the movable contact 7 toward the fixed contact 9. good. In addition, in the embodiment, the main contact 21
The slope formed on the contact surface is formed on other contacts so as to reduce the amount of OT, and it is not limited to the slope, but may also be formed in a non-flat shape.

〔Effect of the invention〕

According to this invention, the base end of the movable contact is pivotally supported by the slide shaft support so that it can move in a direction parallel to the rotating direction of the tip of the movable contact, and the movable contact is supported by the auxiliary spring. By bringing the base end closer to the fixed contact in the on state, the movable contact is placed close to the fixed contact in the on state, but when an abnormal current occurs, the armature is attracted to the yoke and the reversal spring At the same time, the base end of the movable contact is pushed away from the fixed contact by the electromagnetic repulsive force of the movable contact and the fixed contact against the auxiliary spring, and as a result, the sliding movement of the slide shaft support causes the base end of the movable contact to be pushed away from the fixed contact. This has the effect of increasing the opening distance of the movable contact.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the first embodiment of the present invention, Fig. 2 is a cross-sectional view of the main part in the on state, Fig. 3 is a cross-sectional view of the operating process at the time of short circuit, and Fig. 4 is the closing of the contact. FIG. 5 is a side view showing the operating process of the contact of the modified example;
FIG. 6 is a sectional view of the second embodiment in the on state, and FIG. 7 is a sectional view of the operating process during a short circuit. DESCRIPTION OF SYMBOLS 1... Yoke, 2... Contact holder, 3... Armature, 4... Base end part, 5... Slide shaft support,
6... Movable contact, 7... Movable contact, 8... Fixed contact, 9... Fixed contact, 10... Electric circuit section, 1).
... Reversing spring, 12... Auxiliary spring, 27... Opening/closing means Fig. 2. 1921 9 Figure 4

Claims (4)

[Claims] (1) a contact holder having a yoke; an armature supported pivotally by the contact holder and facing the yoke;
A movable contact is provided at the distal end, and a movable contact is pivotally supported on the contact holder by a slide shaft support whose base end is movable in a direction parallel to the rotating direction of the distal end, and a fixed member opposite to the movable contact. a fixed contact having a contact and arranged in parallel to the movable contact so as to generate electromagnetic repulsion; an electric circuit connected to the movable contact and passing between the yoke and the armature; a reversing spring which is installed between an armature and a movable contact and which attracts the armature to a yoke with an abnormal current flowing through the electric circuit section and thereby reverses and opens the movable contact; and an on-state of the movable contact. A circuit breaker comprising: an auxiliary spring that causes a base end portion of the movable contact to approach the fixed contact; and an opening/closing means that drives the contact holder to open and close the movable contact. (2) The circuit breaker according to claim 1, wherein the slide shaft support comprises a movable shaft provided on the movable contact and a guide portion formed on the contact holder. (3) The movable contact and the fixed contact have a high melting point arc contact and a low resistance main contact, and these arc contacts and main contacts are arranged in parallel in the direction connecting the base end and the tip end of the movable contact. The circuit breaker according to claim 1, wherein the main contact is located on the proximal end side of the movable contact. (4) The circuit breaker according to claim (3), wherein either the arc contact or the main contact of the movable contact and the fixed contact forms a slope such that the surface on the adjacent contact side is lowered.