KR970010446B1 - Circuit breaker - Google Patents

Abstract

None.

Description

Circuit breaker

1 is an exploded perspective view showing main parts of an embodiment of the present invention.

FIG. 2A is a plan view of main parts showing a state of a holder supported on the case of FIG.

2b is a cross-sectional view taken along the line B-B in FIG.

3a, b are side and front views of the fragment;

FIG. 4A is a side view showing a fragment of FIG. 3 coupled to the phase barrier rib shown in FIG.

4b is a sectional view taken along the line B-B in FIG.

5 is a plan view of main parts for comparing the distance from the movable contact of the left and right poles to the pressure point of the opening and closing shaft.

6 is an exploded perspective view of another embodiment of the present invention.

FIG. 7A is a top view of FIG. 6. FIG.

FIG. 7B is a sectional view of the open state taken along the line B-B in FIG.

Figure 7c is a sectional view of the input state.

8 is a longitudinal sectional view of a conventional example.

9A is an enlarged side view of the main portion of the conventional example.

FIG. 9B is a sectional view taken along the line B-B in FIG.

10 is a perspective view of the frame shown in FIG.

The present invention relates to a small circuit breaker such as a circuit breaker.

8 shows the overall configuration of a conventional circuit breaker (three-pole wiring breaker), and each mechanism is housed in a housing of a resin molded article made of a case 1 and a cover 2 covering the same. When the breaker is turned on as shown, the current flows into the fixed contactor 3, the movable contactor 4, the lead wire 5, the connecting plate 6, the overcurrent trip device 7, the conductor 8, It flows through the path of the load terminal 9.

The movable contactor 4 is supported at each pole by the holder 10 of the resin molded article, and these holders 10 are connected to each other by an opening / closing shaft 11 formed by a heat body. The opening and closing shaft 11 is inserted into a U-shaped groove (not shown) formed in the upper partition wall 1a of the case 1 to be rotatably supported. In particular, the opening and closing shaft 11 inserted into the U-shaped groove is formed with a flange of an insulating barrier, which is fitted into a groove formed around the U-shaped groove.

The movable contactor 4 is opened and closed by the opening / closing mechanism 12 via the holder 10, and the opening / closing mechanism 12 is supported by the frame 13 having side plates on both sides of the movable contactor 4. When the 14 is coupled to the latch receiver 15, it is supported in the set state shown. As shown in FIG. 8, the latch receiver 15 receives a clockwise rotational force from the latch 14, but rotation is inhibited by the tongs of the trip cross bar 16 coupled to the rear surface thereof. In addition, the opening and closing shaft 11 inserted into the upper partition wall 1a of the case 1 is pressed so as not to be lifted by the holder presser 18 formed on the side plate of the frame 13 to the outside. The frame 13 is made of U-shaped steel plate as shown in FIG. 10, and is formed by bending the bottom plate 13a connecting the left and right side plates and the side plate at the opposite end thereof. The plate 13b is screwed to a support not shown in the case 1. Reference numeral 13c is a hole through which the support shaft of the latch receiver 15 passes, and 13d is an opening or groove through which a support shaft such as the latch 14 passes.

In this state, when the overload current and the short-circuit current flow, the overcurrent trip device is operated so that the trip crossbar 16 is rotated counterclockwise and the tongs 17 are separated from the latch receiver 15. Thus, the latch receiver 15 is rotated clockwise to be released from the latch. Then, the movable contact 4 is opened and stopped to the position of the dashed-dotted line shown due to the operation of the opening and closing mechanism.

By the way, when opening the circuit breaker, it is essential to keep the movable contact 4 at a predetermined opening distance. Therefore, conventionally, as shown, the stopper 19 is formed in the cover 2, or the stopper is formed in the frame 13 for supporting the opening / closing mechanism 12, so that the movable contact 4 can be When it came to the end position, it was caused to collide with this stopper, but when the large current was interrupted, it was considerably heated, and there was a fear that the movable contactor 4 would be deformed during the collision. Moreover, according to the frame 13 and the conventional circuit breaker provided with the stopper in this frame, the latch 14 is released from the latch receiver 15 by the collision or the latch receiver 15 is released from the pincer 17 so that the circuit breaker is prevented. There is a risk of tripping.

As a countermeasure against the above-mentioned problem, an arm used as an insulating barrier is integrally formed in the opening / closing shaft 11 to be inserted into the U-shaped groove of the case partition wall, and a groove including the arm is formed around the groove, Japanese Utility Model Publication No. 59-178843 discloses that the arm is coupled with a wall around the groove to regulate the opening position of the movable contact when the movable contactor opens.

The circuit breaker having this structure will be briefly described with reference to FIG. 9 again. Here, FIG. 9 (a) is a side view of the U-shaped groove, and FIG. 9 (b) is a cross-sectional view taken along the line B-B in FIG. 9 (a). The same numbers as used in the parts of FIG. 8 denote the same parts in FIGS. 9 (a) and 9 (b). In these figures, (a) is the upper partition of the case 1, 20 is the U-shaped groove formed in the upper partition, 21 is the groove formed around the U-shaped groove 20, and 11 is U. The opening and closing shaft inserted into the female groove 20, 22 is formed integrally with the opening and closing shaft 11, the arm serving as an insulating barrier inserted into the groove 21, 23 is the groove (20), (21) It is a fragment used to fill the space of the top of and to increase the insulation distance. In the state in which the movable contactor is opened as shown, the arm 22 is in contact with the circumferential wall of the groove 21 to regulate the opening position of the movable contactor.

According to the above-described structure, the arm 22 has a structure thicker than a simple insulating barrier to withstand the large impact force when the movable contact is opened. The thickness or width of the groove 21 accommodating the arm 22 is limited in its dimensions since the groove is formed within the thickness measurement range of the upper partition. As a result, the end of the arm 22 in contact with the circumferential wall 21a is easily collapsed, and the contact surface of the circumferential wall 21a will be easily recessed or pitted.

When the arm 22 collapses and the circumferential wall 21a is depressed, when the opening and closing shaft 11 rotates in the opposite direction and the movable contactor rotates from the open state to the closed state, the arm 22 and the circumferential wall ( The slip resistance between 21a) is increased. Since the wear powder between the arm 22 and the partition wall 1a is gathered between the opening-closing shaft 11 and the U-shaped groove 20, the rotational resistance of the opening-closing shaft 11 is increased, so that the necessary load increases. In addition, since the stop position of the arm 22 changes, the opening position of the movable contactor 4 and the rotation angle of the holder 10 change, and the movable contactor 4 adversely interferes with the components of the opening and closing mechanism. Therefore, the operation of the built-in component, for example, the auxiliary switch is adversely affected by the rotation of the holder (10).

As described above, according to the conventional example shown in FIG. 9, the width of the groove 21 is limited in selection, so that the arm 22 is formed of the groove 21 as shown in FIG. 9 (b). Since the entire width is filled, there is virtually no room in the width direction of the groove 21. As a result, the fragment 23 intended to be inserted into the upper partition wall 1a cannot enter the gap G between the side wall of the groove 21 and the side surface of the arm 22, so that the opening / closing shaft 11 and the arm 22 are shown. Only the top surface of) is covered. As a result, when the portion of the U-shaped groove 20 is viewed in the lateral direction, a triangular gap 24 is formed between the fragment 23 and the opening and closing shaft 11 as shown in FIG. It causes problems in phase-to-phase insulation when breaking a large current such as a current. In addition, since it is difficult to make a piece 23 having a pointed tip filling the gap 24 by resin molding, there is a possibility that the tip is chipped while processing the piece to make a pointed tip.

As shown in FIG. 8, the opening / closing shaft 11 is supported by pressure so as not to be lifted by the holder press 18 formed in a part of the frame 13 supporting the opening / closing mechanism 12. According to this structure, the shock generated in the movable contactor 4 when the breaker is opened and closed, particularly when the breaker is opened, is transmitted to the frame 13 through the open / close shaft 11. Therefore, there is a risk that the coupling between the frame 13, the latch receiver 15, and the latch 14 supported by the tongs 17 is released and the feeding fails. To avoid this problem, the frame 13 is strengthened by increasing the thickness and width of the frame. In addition, the force of the return spring 25 of the trip cross bar 16 can be increased. However, as the frame 13 is strengthened and the standard of the case 1 is enlarged, it is more disadvantageous. When the force of the return spring is enhanced, the overcurrent trip characteristic is lowered.

According to FIG. 8, the currents flowing through the fixed contactor 3 and the movable contactor 4 are opposite to each other. Therefore, the positive current generates magnetic forces that repel each other. The circuit breaker is configured to utilize a magnetic repulsive force for quickly driving the movable contactor in the open direction when a large current such as a short circuit current flows. However, very large bending stress occurs in the opening and closing shaft 11 using the holder presser 18 as the lever point. Therefore, in order to prevent the opening and closing shaft 11 from being damaged by bending stress, it is necessary to increase the diameter of the opening and closing shaft or to use a shaft made of a strong material, so that a large and expensive case 1 should be provided.

SUMMARY OF THE INVENTION An object of the present invention is to provide a circuit breaker which prevents an impact on a frame supporting a movable contactor and an opening / closing mechanism during opening operation by regulating the opening position of the movable contactor by the combination of the holder and the case partition wall. Another object is to reduce the damage of the coupling portion and the holder of the phase partition wall while maintaining the insulation efficiency between the phases.

Some of the additional objects and other advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the particularly intelligent elements and combinations thereof in the claims.

In order to achieve the above object, the present invention as embodied and broadly described herein provides an opening and closing shaft, a holder connected to the opening and closing shaft, at least one or more movable contacts coupled to the holder, and a support for pivotally supporting the holder. Means and a stopper which, in combination with the support means, regulate the opening position of the movable contact.

The present invention provides a circuit breaker in which each movable contactor is held in a holder of each pole connected to each other by an opening and closing shaft, and the opening and closing shaft is inserted into a U-shaped groove of an upper partition wall of the case to be rotatably supported by the case. In order to achieve the first object, a stopper is formed on the side wall of the upper partition wall of the case, and a part of the holder is brought into contact with the stopper to regulate the opening position of the movable contact.

In this case, the damper is provided on the stopper protruding from the contact surface of the holder. Therefore, the impact between the holder and the stopper can be reduced by the holder contacting the contact surface after the holder hits the damper during the opening operation.

The position of the movable contactor is controlled by coupling the holder to the stopper of the side wall of the upper partition wall, thereby preventing damage to the movable contactor and impact on the support frame of the opening / closing mechanism. Moreover, since the insulation barrier inserted into the groove of the partition wall only serves as an original insulation function, the thickness of the barrier can be reduced. A little space or clearance can be made along the width direction of the insulation barrier inserted into the groove, and a fragment can be inserted into the clearance to increase the insulation of the barrier.

In addition, by installing a damper on the stopper with which the holder contacts, colliding the holder with the damper to reduce the kinetic energy of the holder, and contacting the holder with the stopper to regulate the opening and closing position, thereby preventing malfunction caused by the impact of the circuit breaker. Can be effectively prevented. In addition, the positional accuracy can be improved by reducing the burden on the contact portion.

A fragment is inserted to cover the opening and closing shaft in the U-shaped groove, and the opening and closing shaft is pressed by the cover through the fragment. Therefore, the shock due to the opening and closing operation of the breaker is not directly applied to the frame. By pressing the opening / closing shaft with a fragment inserted into the upper partition, it is possible to press the opening / closing shaft to a portion closer to the movable contactor of the left and right poles than other positions. When the opening / closing shaft is pressed to this position or held through the side plate of the frame located inside the upper partition, the bending stress caused by the magnetic repulsion force is reduced. In addition, since the contact surface between the fragment and the opening and closing shaft is larger than the width of the frame side plate, it is easy to configure the contact surface in an arc shape, so that the rotation of the opening and closing shaft is smooth and the bearing surface of the opening and closing shaft is reduced. In addition, the provision of a fragment in the U-shaped groove of the phase partition wall fills the gap between the phases, thereby improving the insulation performance.

The accompanying drawings, which are incorporated in and constitute a part of this specification, are intended to help illustrate the principles of the invention by illustrating several embodiments of the invention in conjunction with the description.

The preferred embodiments of the invention illustrated in the accompanying drawings will now be described in detail. If possible, the same number will be used to refer to the same or similar parts throughout the conducting surface.

1 is a perspective view of a main portion of a three-phase circuit breaker. In FIG. 1, the holder 10 is a resin molded article for holding movable contacts of each phase not shown. Each phase is connected to each other by the opening-closing shaft 11 integrally formed. In the center of the opening / closing shaft 11, a flange-type insulating barrier is integrally formed. The holder 10 has a fork-shaped end formed by connecting the left and right walls to an arc-shaped bottom. The movable contact, not shown, is held through the pins between the side plates.

On the other hand, the case 1 of the resin molding agent is divided into three-phase blocking chambers by the phase partition wall 1a. Although not shown in the drawing, each cutoff chamber houses wirings or leads of each phase. A U-shaped groove 20 into which the opening and closing shaft 11 connecting the holder 10 is inserted is formed on an upper surface of the upper partition wall 1a. A groove 21 is formed around the U-shaped groove 20 to accommodate the insulating barrier 26. Moreover, the rectangular stopper 27 is integrally formed in the outer surface of the upper partition 1a, and the opening position after a part of the holder 10 contacts the stopper 27 is regulated.

When the movable contactor is opened as described above, a jaw portion 10a is formed on the side of the holder which contacts the stopper 27 of the upper partition wall 1a. Reference numeral 28 is a hole through which a pin connecting the toggle link of the opening and closing mechanism and the holder 10 passes.

2 shows a state of the case 1 in which the holder 10 is supported. FIG. 2A is a plan view of the main portion thereof, and FIG. 2B is a sectional view taken along the line B-B.

As shown in the figure, the opening and closing shaft 11 is inserted into the U-shaped groove 20 of the upper partition wall 1a, and the holder 10 is rotatably supported by the case 1. The insulating barrier 26 is inserted into the groove 21 formed around the U-shaped groove 20.

2B shows a state in which the movable contact 4 is opened by a dashed-dotted line. In this state, the jaw portion 10a on the side of the holder 10 is in contact with the stopper of the upper partition wall 1a to regulate the opening position of the movable contact 4.

According to the above structure, since the contact between the holder 10 and the stopper 27 is performed outside the upper partition wall, the contact portion of the upper partition wall can have a sufficient thickness without limiting the width of the upper partition wall 1a, so To prevent it.

3 shows a fragment inserted into the U-shaped groove 20 of the upper partition wall 1a. 3A is a side view thereof, and 3B is a front view thereof. As shown in FIGS. 3A and 3B, the fragment 23 includes a body portion 29 to be inserted into the groove 21 and a wing portion 930 to be inserted into the U-shaped groove 20. In the two portions, the portion covered by the opening and closing shaft 11 is removed in an arc shape. The arc-shaped surface formed in the body portion 29 has a groove 29a in which the insulating barrier 26 is located.

4A is a side view, and FIG. 4B is a perspective view of the main portion of the upper partition wall 1a in which the fragments 23 are inserted in a sectional view taken along the line B-B in FIG. 4A. Along the width direction of the insulating barrier 26 inserted into the groove 21 of the upper partition wall 1a, as shown in FIG. 4B, there is a gap into which the body portion 29 of the fragment 23 is inserted, thereby insulating the barrier. It covers the upper half of (26). Thus, the triangular portion 24 that occurs in the conventional structure shown in FIG. 9 is filled with the body portion 29.

Referring again to FIG. 1, the cover 2 has an upper partition wall 2a corresponding to the upper partition wall 1a of the case 1, and the bottom surface of the upper partition wall 2a covers the cover 2. When installed in (1), the upper surface of the partition 1a partition wall 1a is in close contact with the upper surface. As a result, the fragment 23 inserted into the U-shaped groove 20 is pressed and held by the upper partition 2a and the opening / closing shaft 11. The opening and closing shaft 11 is pressed through the fragment 23.

5 is a plan view comparing the case where the opening and closing shaft 11 is pressed by the fragment 23 and the case where the opening and closing shaft 11 is pressed by the conventional holder presser 18. The frame 13 of FIG. 8 is also shown by the dashed-dotted line. In FIG. 5, 8, 9a, and 9b, the distance from the movable contactor 4 of the left and right poles to the fragment 23 is L ₁ , and the distance from the movable contactor 4 to the holder presser 18 is shown. L ₂ , clearly L ₂ is larger than L _{1 in} FIG. 5, but not so if the holder presser 18 is located inside or between the upper partitions 1a as in FIGS. 8, 9a and 9b. . Therefore, the bending stress of the opening and closing shaft 11 due to the self-repulsion force on the movable contactor 4 is shown in FIG. 5 in which the opening and closing shaft 11 is pressed by the fragment 23 than in the conventional circuit breaker shown in FIG. Is smaller in the circuit breaker according to the embodiment.

Moreover, according to the structure in which the cover 2 presses the opening / closing shaft 11 via the fragment 23, any shock generated when the circuit breaker is opened and closed is not transmitted directly to the frame 13. Thus, the latch 14 supported by the frame 13 and the latch receiver 15 and the clamping claw 17 (shown in FIG. 6) of the trip cross bar 16 are not loosened. In addition, the fragment 23 serves as a bearing to smoothly rotate the opening and closing shaft 11 and to eliminate the gap between the phases to improve the insulation performance.

Next, FIGS. 6 and 7 show another embodiment in which a damper is provided on the stopper with which the holder contacts. FIG. 6 is an exploded perspective view of the main part, FIG. 7A is a plan view of the main part, FIG. 7B is a sectional view taken along the line B-B in the open state, and FIG. 7C is a state similar to that of FIG. The parts of FIGS. 6 and 7 corresponding to the parts of the embodiment shown in FIG. 5 use the same reference numerals.

In Fig. 6, the holder 10 is formed with a projection 10b extending rearward (load side) integrally with the side wall. The stopper 27 which the protrusion 10b contacts at the time of opening of the movable contact 4 is integrally formed in the side surface of the case partition 1a. The stopper 27 is formed with a vertical cylindrical hole 31 at the bottom for receiving the damper 34 composed of the compression spring 32 and the rubber buffer 33. The shock absorbing material 33 is supported by the compression spring 32, and is positioned at the position lifted from the contact surface 27a of the stopper 27 in the input state of the movable contactor 4 as shown in FIG.

When the movable contactor 4 moves from the closed state to the open state, the protrusion 10b first collides with the shock absorbing material 33 to press against the compression spring 32, and then the stopper 27 as shown in FIG. 7B. Stop in contact with. According to this configuration, the kinetic energy of the holder 10 and the movable contactor 4 is absorbed by the damper 34 before the protrusion 10b comes into contact with the stopper 27, so that the protrusion 10b gradually falls on the stopper 27. It stops while touching. As a result, damage to the projections 10b and the stopper 27 is alleviated more than in the conventional case. Since these design conditions are alleviated compared with the prior art, this part can be miniaturized.

According to the present invention, a projection is provided on the side surface of the upper partition wall, and a part of the holder is brought into contact with the projection to regulate the opening position of the movable contactor, thereby preventing damage to the movable contactor due to contact between the movable contactor and the stopper. Installing a stopper on the frame of the opening and closing mechanism can prevent the movable contact from tripping suddenly.

In the conventional system, a gap that reduces insulation performance when the insulation barrier, the arm, and the phase partition wall are combined may be formed, but according to the present invention, the insulation performance between phases does not decrease due to the gap. Since the coupling between the holder and the stopper is performed outside the partition wall of the case, the coupling portion can be provided with a sufficient thickness to secure strength, and a damper can be installed to mitigate the impact.

Further, according to the present invention, since the fragment inserted into the U-shaped groove of the upper partition wall is pressed by the cover to ensure the opening and closing shaft is securely held, the trip state is prevented. In a conventional system, such a trip state is caused by the impact generated when the frame supporting the opening and closing mechanism maintains the opening and closing shaft, and may also be caused by bending stress due to the electromagnetic repulsive force generated on the opening and closing shaft. In the present invention, this bending stress is reduced. In addition, according to the present invention, since the fragment is inserted into the interphase partition wall, the opening and closing shaft is smoothly rotated to improve the interphase insulation performance.

Without departing from the spirit or scope of the present invention, those skilled in the art can variously modify and change the circuit breaker of the present invention.

Other embodiments of the present invention will also be readily appreciated upon consideration of the detailed description and practice presented herein. It is intended that the specification and examples be considered as typical with the true spirit and outline of the invention being indicated by the appended claims.

Claims (8)

The lap axle 11, a holder 10 connected to the lap axle 11 to hold the movable contactor 4, support means for rotatably supporting the lap axle 11, and the movable contactor 4. In the circuit breaker composed of a stopper (27) or the like coupled with the support means to stop the opening and closing shaft 11 to regulate the opening position, the circuit breaker is accommodated in the case (1), the stopper (27) is formed on the side surface of the partition (1a) of the case (1), wherein a part of the holder (10) is in contact with the stopper (27). The circuit breaker of claim 1, wherein the circuit breaker includes a plurality of wiring electrodes. 3. A circuit breaker according to claim 2, wherein said holder (10) has said respective poles. The method of claim 1, wherein the support means has a U-shaped groove 20 formed in the upper partition wall (1a) of the case (1), the lap shaft 11 is inserted into the U-shaped groove (20) Circuit breaker, characterized in that. The circuit breaker of claim 1, further comprising a damper (34) mounted on the stopper (27) to contact the protrusion (10b) of the holder (10), wherein the holder (10) of the circuit breaker The circuit breaker characterized in that the contact with the contact surface of the stopper (27) after colliding with the damper (34) during the opening operation. 5. The cover (2) according to claim 4, further comprising a piece (23) having a lap shaft (11) inserted into the U-shaped groove (20), wherein the piece (23) is placed on a cover (2) covering the case (1). Circuit breaker, characterized in that pressed by. 2. The circuit breaker according to claim 1, wherein the stopper (27) is rectangular. 6. A circuit breaker as claimed in claim 5, characterized in that the damper (34) consists of a compression spring (32) and a rubber buffer (33).

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