JP4022524B2 - Circuit breaker - Google Patents

Description

  The present invention relates to a circuit breaker such as a circuit breaker for wiring and an earth leakage breaker, and more specifically, provides a novel mechanism for downsizing or thinning of an opening / closing mechanism.

In a conventional circuit breaker with an upside-down handle, the quick-release / early-opening / closing mechanism has a toggle that is configured so that the upper link and the lower link are almost in a straight line when turned on to ensure contact pressure. A link mechanism is used. (For example, refer to Patent Document 1).
Further, as a special example, there is known a structure that does not employ a toggle link mechanism, ensures contact pressure with a contact spring, and uses an auxiliary spring at the time of opening. (For example, refer to Patent Document 2).

Japanese Patent No. 3166908 (FIG. 6) JP 2001-250465 A (FIG. 3)

  In a conventional circuit breaker, generally, in a toggle link mechanism used for an opening / closing mechanism, a configuration is used in which an upper link and a lower link extend substantially in a straight line. According to this configuration, a space for extending the upper link and the lower link is required in the casing, and the outer dimensions of the casing are increased. In addition, as a circuit breaker configured to fold the upper link and the lower link, there is a prior invention by the applicant of the present application, but when the fixed contact and the movable contact are welded, or the operation of the opening and closing mechanism part at the time of trip, There is a problem that needs improvement.

  The present invention has been made to solve the above-described problems. A first object of the present invention is to obtain a circuit breaker having a downsized configuration in the opening / closing mechanism. A second object is to obtain a circuit breaker that can be miniaturized and has a smooth handle operation. The third object is to improve the operation of the opening / closing mechanism when the fixed contact and the movable contact are welded or when the trip occurs.

The circuit breaker according to the present invention is mainly characterized by the opening / closing mechanism, and one end is pivotally supported by the frame and the other end is engaged with a trip bar interlocked with the overcurrent tripping device. A latch that is configured so that one end is pivotally supported by the frame and the other end is normally locked to the latch, and one end is pivotally connected to the other end of the lever. An upper link having a lower spring pin at the other end, a lower link having one end pivotably connected to the upper link via the lower spring pin, and one end pivotable to the frame. A connect link that is pivotally supported and the other end is connected to a push plate that operates the movable contact, and the other end of the lower link is rotatably connected to the intermediate portion, and is rotatable to the upper end side of the frame. With the handle provided on A sliding groove formed in the frame near the position of the handle, an upper spring pin that is engaged with the handle and slides in the sliding groove by the rotation of the handle, and the upper spring pin and the lower spring pin. In a circuit breaker having a suspended main spring, the lower link and the upper link are folded so that the other end of the lower link is located between the one end and the other end of the upper link. It is a thing.

  Further, when the fixed contact and the movable contact are welded, the handle is engaged with the forced engagement portion of the connect link so that the handle is not rotated to the off position.

  In addition, the lever is provided with an opening protrusion, and the connection link is provided with a protrusion abutting portion with which the opening protrusion abuts.When the trip is started, the opening protrusion is in contact with the protrusion abutting portion of the connect link to start the connect link. It is configured to assist.

  In the opening / closing mechanism portion, the lower link and the upper link are folded so that the other end of the lower link is positioned between the one end and the other end of the upper link. The circuit breaker can be downsized easily.

  Moreover, when the fixed contact and the movable contact are welded, it is possible to suppress the spread of accidents due to welding.

  Further, when tripping due to overcurrent, the opening of the movable contact can be accelerated by assisting the start of the connect link.

Embodiment 1 FIG.
1 and 2 show a circuit breaker 100 according to Embodiment 1 for carrying out the present invention. FIG. 1 is a front view showing the entire circuit breaker, and FIG. 2 is a main part of the present invention. It is a perspective view which expands and shows the opening-and-closing mechanism part which is. 1 is normally described as a side view as a drawing of the circuit breaker, but in this embodiment, the drawing of FIG. 1 will be described as a front view in relation to other drawings.

  In FIG. 1, a base 1 and a cover 2 constitute a casing of a circuit breaker, and are formed of a synthetic resin material. The opening / closing mechanism 3 is disposed inside the housing, and a handle 12 described later projects from the handle window hole 2 a of the cover 2 to the surface of the cover 2. The open / close contact portion 4 has a configuration generally referred to as a bridged two-contact system. The overcurrent trip device 5 operates the open / close mechanism 3 when an overcurrent flows through a power supply side terminal 6 and a load side terminal 7 connected to an electric circuit (not shown). Of the configuration. An arc extinguishing device and a terminal screw are also provided, but they are not shown because they are not related to the present invention.

  In FIG. 2, the opening / closing mechanism unit 3 includes a link mechanism such as a connect link 13 and an upper link 14, a handle 12 supported by a handle shaft 31, and the like between two frames 11. The main spring 19 is suspended between an upper spring pin 32 operated by the handle 12 and a lower spring pin 35 connected to the link mechanism, and expands and contracts when the opening / closing contact portion 4 is opened / closed. That is, the expansion and contraction is performed by rotating the link mechanism so that the direction acting on the link mechanism is reversed, and the opening / closing operation is performed. The push plate 20 is connected to a link mechanism, and moves the movable contact 22 provided at one end to and from a fixed contact (not shown). 18 is a known trip bar which is actuated by the overcurrent trip device 5 as described later.

  Next, details of the components of the opening / closing mechanism 3 will be described with reference to FIGS. 3 is a perspective view of the frame 11, FIG. 4A is a front view, and FIG. 3B is a side view. This frame 11 is a combination of a pair of frame plates 111 and 112 that are formed almost symmetrically using a steel plate having a thickness of 1 mm. As an outline of the size, for example, for a circuit breaker of 100 amp frame, the dimension H is 44 mm, the dimension W is 23 mm, and the dimension T is 6 mm. 3 and 4, the frame 11 is a combination of the frame plates 111 and 112 (there is no component such as a link mechanism inside), but the frame 11 includes the open / close contact portion 4. The frame plates 111 and 112 are combined such that a handle, a link mechanism, shafts and the like described later are sandwiched between the frame plates 111 and 112 from both sides.

  In the figure, there are various through holes and guide pieces as follows, and related parts will be described later. That is, the handle 12 is pivotally supported in the through hole 11a. The upper spring pin 32 is fitted in the arcuate sliding groove 11b so that it can slide. A connect link 13 is pivotally supported in the through hole 11c. A latch 17 is pivotally supported in the through hole 11d. A lever 16 is pivotally supported in the through hole 11f. A trip bar 18 is pivotally supported in the through hole 11g. The penetrating window 11 h is used as an operating space of the lower spring pin 35 and a part of an edge of the operating space as a locking portion of the lower spring pin 35. The guide piece 11k is provided in order to suppress misalignment of components arranged near the center position between the frame plates 111 and 112. Reference numeral 11m denotes a screw hole, which is used for screwing the opening / closing contact portion 4 to the base 2.

  FIG. 5 shows a handle 12 made of, for example, a synthetic resin material, where (a) is a front view, (b) is a side view, and (c) is a rear view. In the figure, reference numeral 12a denotes an engagement hole, into which an upper spring pin 32 described later is fitted. However, since the upper spring pin 32 follows the arc-shaped sliding groove 11b formed in the frame 11, the position of the upper spring pin 32 moves in the vertical direction when viewed from the handle 12 side. Therefore, the engagement hole 12a is formed as a long hole extending in the direction of the position of the support hole 12b, or is formed into a slot groove having an opening at the end edge of the handle 12 by extending the long hole. Reference numeral 12c denotes an engaging protrusion, which is a portion that engages with a later-described connect link 13 during contact welding.

  FIG. 6 shows a connect link 13 formed of, for example, a steel plate, where (a) is a front view and (b) is a top view. In the figure, the through hole 13a is a hole for pivotally supporting the through hole 11c of the frame 11. The through-hole 13b is a hole that is pivotably connected to a lower link 15 described below before being clamped by the frame 11. The through hole 13c is a hole for connecting a push plate 20 described later. Reference numeral 13f denotes a protrusion abutting portion with which an opening protrusion 16d provided on the lever 16 described later abuts. Reference numeral 13e denotes an inflection point, and 13h denotes a contact locking portion. Reference numeral 13d denotes a forcibly engaging portion that engages with the engaging projection 12c of the handle during contact welding, and 13e denotes a forcibly rotating portion.

  FIG. 7 shows an upper link 14 formed of, for example, a steel plate, where (a) is a front view and (b) is a bottom view. In the drawing, a through hole 14a is a hole for mounting a lower spring pin 35 described later. The through hole 14b is a hole for pivotally connecting to a lever 16 described later before being sandwiched by the frame 11. Reference numeral 14c denotes a U-bend portion, and the through hole 14a is formed through the U-bend portion 14c.

  FIG. 8 shows a lower link 15 formed of, for example, a steel plate, where (a) is a front view and (b) is a bottom view. In the figure, the through-hole 15a is a hole for pivotally connecting to the connect link 13 before being sandwiched by the frame 11 as described above. The through hole 15 b is a hole for connecting to the upper link 14 via the lower spring pin 35 when sandwiched by the frame 11.

  FIG. 9 shows a lever 16 formed of, for example, a steel plate, where (a) is a front view and (b) is a side view. In the drawing, a through hole 16a is a hole for pivotally connecting to the upper link 14 before being sandwiched by the frame 11. The through hole 16b is a hole for rotatably supporting the through hole 11f of the frame 11. The locking protrusion 16c is formed to be locked to a rotation locking portion 17c of the latch 17 described later. Reference numeral 16d denotes an opening protrusion, which is provided so as to come into contact with the forcibly engaging portion 13d of the connect link 13 during a trip.

  FIG. 10 shows a latch 17 formed of, for example, a steel plate, where (a) is a front view and (b) is a side view. In the figure, reference numeral 17a denotes a hole for rotatably supporting the through hole 11d of the frame 11. Reference numeral 17b denotes a trip locking portion that is locked to a trip bar 18 described later. Reference numeral 17 c denotes a rotation locking portion for locking the rotation of the lever 16.

The connect link 13, the upper link 14, the lower link 15, the lever 16, and the latch 17 are each formed of a steel plate having a thickness of 1 mm. And it is clamped by the frame 11 together with the handle 12. In this clamping, the five parts including the connect link 13, the upper link 14, the lower link 15, the lever 16, and the latch 17 must be clamped in the 6 mm space of the frame 11 so as to be rotatable.
In this case, in order to reduce the width dimension of the opening / closing contact portion 4, the above five components are inserted in close contact. That is, the space of the frame 11 is set so that six parts cannot be inserted if the parts have the same thickness. For this reason, some have been bent so that adjacent parts do not interfere.

  FIG. 11 shows a trip bar 18 formed of a synthetic resin material. FIG. 11A is a front view seen from the link mechanism side, and is partially cut away. (B) is sectional drawing in the KK line | wire. In the figure, 18a is a through hole for pivotally supporting the frame 11. Reference numeral 18b denotes a latch locking portion.

Next, a state in which each of the above components is assembled as an opening / closing mechanism will be described. However, if all parts are shown in a lump, the shape of each part and the relationship with other parts will be difficult to understand, so the drawing (illustrated) will be divided as if it is on or off, Only the parts related to the state are shown, and other parts will be omitted from the description. In this case, for the sake of explanation, there are portions where the relationship between the parts before and after (the relationship between the solid line and the broken line) is different from the relationship in FIG.
FIG. 12 is a side view of the opening / closing mechanism unit 3, and the five link parts including the connection link 13, the upper link 14, the lower link 15, the lever 16, and the latch 17 are in close contact between the frame plates 111 and 112. Indicates that it has been inserted into the state. Further, the main spring 19 is suspended between the upper spring pin 32 and the lower spring pin 35 on both outer sides of the frame 11.

  First, FIG. 13 shows a state where the stationary contact 21 and the movable contact 22a are closed, that is, an on state. In addition, 21a is a fixed contact and 22a is a movable contact. In this state, the handle 12 is in a position rotated in the direction of the arrow RA about the handle shaft 31, and the upper spring pin 32 engaged with the engagement hole 12 a of the handle 12 is formed in an arc shape of the frame 11. It is brought to the left side of the sliding groove 11b. The upper spring pin 32 is provided with a roller 32a for smooth movement with respect to the sliding groove 11b. Since a strong force from the main spring 19 is applied to the roller 32a, a metal roller considering the durability is desirable. The connect link 13 is rotatably supported by a link support shaft 33 provided in the through hole 11 c of the frame 11. One end of the lower link 15 is rotatably connected to the connect link 13 by a link connecting shaft 34, and the other end of the lower link 15 is a lower spring provided in a through hole 14a in the U-bending portion 14c of the upper link 14. A pin 35 is rotatably connected to the upper link 14. An upper end side of the upper link 14 is rotatably connected to an upper end side of a lever 16 described later by a lever connecting shaft 36. When the handle 12 is manually operated from on to off and from off to on, the lever connecting shaft 36 is always in a predetermined position (see FIG. 13).

  The main spring 19 is a pair of tension springs and is suspended between both ends of the upper spring pin 32 and both ends of the lower spring pin 35. The main spring 19 applies an urging force that rotates in the direction of the arrow RB about the lever connecting shaft 36 to the upper link 14. The rotation of the upper link 14 is stationary in a state where the lower spring pin 35 is in contact with and locked to the window hole portion 11 h of the frame 11. Further, the rotational biasing force of the upper link 14 is transmitted to the connect link 13 via the lower link 15, and the biasing force is applied so that the connect link 13 rotates about the link support shaft 33 in the direction of the center arrow RC. ing. The turning biasing force of the connect link 13 works so as to close the fixed contact 21 and the movable contact 22. That is, the push plate 20 is connected to the tip of the connect link 13 by the push plate connecting shaft 37, and the movable contact 22 is provided on the push plate 20. Although the fixed contact 21 is provided to face the movable contact 22, the fixed contact 21 and the movable contact 22 according to this embodiment are generally of a bridge type two-contact type as shown in FIG. It is the composition called. The movable contact 22 is configured to close to the fixed contact 21 with a predetermined contact pressure by an urging force of a contact pressure spring (not shown) built in the push plate 20.

  As described above, as shown in FIG. 13, the circuit breaker according to the present invention has an upper link with the lower link 15 so that the other end of the lower link 15 is located between one end and the other end of the upper link 14. Since the link 14 is configured to be turned on in the folded state, the circuit breaker can be easily downsized.

  Next, an operation for changing the ON state in FIG. 13 to the OFF state in FIG. 14 will be described. This turning-off operation is performed by tilting the handle 12 to the left (turning in the direction of arrow LA). That is, when the handle 12 is rotated to the left, the upper spring pin 32 is guided to the sliding groove 11a of the frame 11 and moved to the right as shown in FIG. In the course of this movement, when the action line of the main spring 19 suspended between the upper spring pin 32 and the lower spring pin 35 exceeds the position of the lever connecting shaft 36, the action direction of the main spring 19 with respect to the upper link 14 is changed. Invert. By this reversal, a biasing force that rotates in the direction of the arrow LB about the lever connecting shaft 36 is applied to the upper link 14. When the upper link 14 rotates in the direction of the arrow LB, an urging force is also applied to the connect link 13 via the lower link 15. By this urging force, the connect link 13 rotates in the direction of arrow LC about the link support shaft 33. Accordingly, the movable contact 22 is separated from the fixed contact 21 via the push plate 20 connected to the tip of the connect link 13 and is turned off as shown in FIG. The operation to turn from OFF to ON is performed by tilting (turning) the handle 12 to the right side. In this case, the reversal of the action direction of the main spring 19 and the rotation of the upper link 14 and the like are as follows. The description is omitted because it is only in the opposite direction to the above.

  In the above description, when the handle 12 is manually operated from on to off and from off to on, the lever connecting shaft 36 is always held at a predetermined position (position shown in FIG. 13). The relationship of the configuration in the on state will be described with reference to FIG. For this holding, there are a lever 16 rotatably supported by a lever support shaft 38 provided on the frame 11 and a latch 17 rotatably supported by a latch support shaft 39. The upper end side of the lever 16 is connected to the upper end side of the upper link 14 by a lever connecting shaft 36. Accordingly, in the state of FIG. 15, the lever 16 is attached to the main spring 19 suspended from the lower spring pin 35 via the upper link 14 so as to rotate in the direction of the arrow LD about the lever support shaft 38. It will be.

  The state in which the lever 16 is urged in the direction of the arrow LD is locked by the latch 17 as follows. That is, the latch 17 is rotatably supported on the frame 11 by the latch support shaft 39. However, the latch 17 is normally rotated in the arrow LE direction by the weak spring 23 provided on the latch support shaft 39. It is energized. As shown in the component diagram of FIG. 10, the latch 17 has a rotation locking portion 17c formed by being bent in a U-shape. The locking protrusion 16c formed on the lever 16 is engaged, and the rotation of the lever 16 in the arrow LD direction is locked. Since this engagement is engaged by the strong force of the main spring 19, the urging force of the twist spring 23 (turning force in the direction of the arrow LE) is canceled, and the latch 17 is moved to the arrow RD by the turning force of the lever 16. It receives a biasing force that rotates in the direction. At this time, the latch 17 is locked by a known trip bar 18 so as not to rotate. Since it is configured as described above, the lever connecting shaft 36 is always held at a predetermined position (position shown in FIG. 13).

  This holding will be described with reference to FIG. In this case, the upper link 14 is rotated in the direction of the arrow LB about the lever connecting shaft 36 by the operation of the handle 12. However, similarly to the on state, the main spring 19 suspended from the lower spring pin 35 causes the lever 16 to be pivoted about the lever support shaft 38 in the direction of the arrow LD via the upper link 14. It will be. Therefore, as in the ON state, the lever connecting shaft 36 is always held at a predetermined position (position shown in FIG. 12). As can be understood from the above, when turning on and off, the lever connecting shaft 36 is the center, and the main spring 19 is reversed and the upper link 14 is operated.

  Next, a trip operation (trip) when an overcurrent exceeding a predetermined value flows will be described. When an overcurrent flows, the overcurrent tripping device operates to rotate the trip bar 18 as shown by an arrow LH in FIG. That is, in the on state of FIG. 15, the relationship between the trip bar 18, the latch 17, the lever 16, and the like is as shown in the figure. In this state, when the trip bar 18 rotates in the arrow LH direction, the latch 17 locked to the trip bar 18 is released. The latch 17 is in the clockwise direction (in the direction of the arrow RD) when the latching projection 16c of the lever 16 is engaged with the pivotal locking portion 17c formed by being bent in a U shape as described above just before the latch 17 is released. A biasing force that rotates is applied. Accordingly, the latch 17 is rotated in the direction of the arrow RD as shown in FIG. 17, the lever 16 is disengaged from the latch 17 and is rotated in the direction of the arrow LD by the urging force of the main spring 19, and the position shown in FIG. To stop. This stop is stopped by a stopper 11 n provided on the frame 11 by the lever 16. When the lever 16 is stopped, the handle 12 is engaged with the tip of the lever 16, and the handle 12 stops at an intermediate position between on and off as shown in the figure. Thereafter, the trip bar 18 returns to its original position by the biasing force of a twist spring (not shown). Further, the reset operation for returning from the trip state to the normal state is performed by turning the handle 12 in the off direction, as in the case of the conventional circuit breaker. The explanation is omitted because it is not directly related to the gist.

According to the circuit breaker having the above-described configuration, the size of the opening / closing mechanism unit 3 makes it easy to cope with application to an attached device or a leakage breaker. Further, since the range of movement when the handle 12 is turned from on to off or from off to on is small, the handle window hole 2a of the cover 2 becomes small. This makes it easy to display various symbols or nameplates on the front surface of the cover 2.
In the above-described embodiment, the slide groove 11b is formed in the frame 11, and the main spring 19 is suspended between the upper spring pin 32 and the lower spring pin 35 that slide in the slide groove 11b. 12, the upper link 14 is rotated by sliding the upper spring pin 32 to move the movable contact 22 in and out of the fixed contact 21. For example, Japanese Patent No. 3166908 (FIG. 6). The main spring 19 may be driven directly by the handle 12 as shown in FIG. In addition, the opening / closing mechanism 3 according to the present invention can be applied not only to the bridge-type two-contact type switching contact 4 but also to a general type switching contact.

Embodiment 2. FIG.
In the above configuration, the arc-shaped sliding groove 11b formed in the frame 11 is formed in an arc shape that is inclined in a direction in which the main spring 19 is extended as the handle 12 is turned from on to off. . This is designed to generate a biasing force that returns the handle to the original on or off position when the handle is not operated or when the hand is released during the operation. In this case, the arc shape of the sliding groove 11b may be a simple arc shape, but a more desirable operation can be obtained if it is a special arc shape as shown in FIG. That is, in the sliding groove 11b, as shown in the figure, the arc S on the lower side is inflection point at an approximately middle position of the sliding groove 11b, and the above inflection point in the vicinity of the lower spring pin 35 with the radius center. It is made into the circular arc shape formed by two types of radial dimensions R-1 and R-2. That is, a substantially square shape with the intermediate position as the inflection point is formed. Note that the upper arc U does not have to be considered in particular because the upper spring pin 32 is not in contact.

  By forming the sliding groove 11b as described above, it is possible to increase the handle biasing force when the handle 12 is turned from on to off and the turning is stopped halfway. Return to the on position. Even when the handle 12 is turned from off to on and stopped halfway, the handle 12 surely returns to the off position.

Embodiment 3 FIG.
In the above configuration, the engagement hole 12a of the handle 12 has been described as a long hole or a slit groove. However, when the engagement hole 12a is a simple long hole or a simple slit groove, the upper spring pin 32 is moved into the arcuate sliding groove 11b of the frame 11 when the handle 12 is turned off from on. The pressing force increases and it is difficult to obtain a smooth rotation of the handle 12. For this reason, the engagement hole 12a is shaped as shown in FIG. That is, when the handle 12 is on, the engagement hole 12a includes a pressing portion 12c that presses the upper spring pin 32 in a direction along the shape of the sliding groove 11b. In this embodiment, for example, as shown in FIG. 19, the engagement hole 12a has a pressing direction that is about 27 degrees upward from a line perpendicular to the center line connecting the handle 12 and the upper spring pin 32. Set.

The upward angle is obtained by calculation or experiment. When the angle of 27 degrees is increased, the pressing force against the sliding groove 11b is reduced, but the engagement hole 12a needs to be increased. As a result, there is a problem that the gap with the upper spring pin 32 becomes large and the opening / closing operation is not smooth. In the above configuration according to the present invention, this angle is suitably 27 degrees.
Note that the pressing portion 12c can be set in the same way when the handle 12 is turned from off to on. By the pressing portion 12c of the engagement hole 12a as described above, the movement of the upper spring pin 32 is smooth and the operation of the handle 12 is facilitated.

Embodiment 4 FIG.
In the above configuration, when an abnormal state occurs in the circuit breaker, the fixed contact 21 and the movable contact 22 may be welded in a closed state. In this state, when the handle 12 is turned in the off direction (arrow LA direction), the handle 12 is turned off as shown in FIG. 14, but the fixed contact 21 and the movable contact 22 are closed, that is, , Fixed contact 21a and movable contact 22a
Is in a welded state. Since this state is dangerous, the structure of the present invention prevents the handle 12 from rotating to the off position in the welded state of the contacts.
That is, in FIG. 20, when the handle 12 is turned in the off direction (arrow LA direction) with the fixed contact 21 and the movable contact 22 closed by welding as shown in the figure, the handle 12 is formed. The engaging protrusion 12c is stopped by engaging with the forced engaging portion 13d of the connect link 13 and cannot be turned to the off position (the position of the handle indicated by the one-dot chain line). In this stopped position, the main spring 19 does not exceed the position of the lever connecting shaft 36, so the direction of action of the main spring 19 on the upper link 14 does not reverse. For this reason, the handle 12 is not turned off and returns to the original on position. According to this configuration, when the fixed contact 21a and the movable contact 22a are welded, it is possible to suppress the expansion of the accident due to the welding.

Embodiment 5 FIG.
In addition, in the structure of this invention, when the welding of the contact in the said Embodiment 4 is light, it can be repaired by forcibly rotating the handle 12. That is, in the state of FIG. 20, if the handle 12 is forcibly rotated to the off position (the position of the handle indicated by the alternate long and short dash line), the engagement protrusion 12c engages with the forcible rotation portion 13e of the connect link 13. Thus, the connect link 13 is forcibly rotated in the direction of the arrow LC. If this forcible rotation is possible, the welded contact can be peeled off and turned off. According to this configuration, similarly to the fourth embodiment, when the fixed contact 21a and the movable contact 22a are welded, it is possible to suppress the expansion of the accident due to the welding.

Embodiment 6 FIG.
In the configuration of the first embodiment, when an overcurrent flows, the overcurrent tripping device operates as is well known to rotate the trip bar 18 as indicated by an arrow LH in FIG. When the trip bar 18 rotates in the direction of the arrow LH, the latch 17 locked to the trip bar 18 is released. The latch 17 is in the clockwise direction (in the direction of the arrow RD) when the latching projection 16c of the lever 16 is engaged with the pivotal locking portion 17c formed by being bent in a U shape as described above just before the latch 17 is released. A biasing force that rotates is applied. Accordingly, the latch 17 is rotated in the direction of the arrow RD as shown in FIG. 17, the lever 16 is disengaged from the latch 17 and is rotated in the direction of the arrow LD by the urging force of the main spring 19, and the position shown in FIG. To stop. This stop is stopped by a stopper 11 n provided on the frame 11 by the lever 16. When the lever 16 is stopped, the handle 12 is engaged with the tip of the lever 16, and the handle 12 stops at an intermediate position between on and off as shown in the figure. Thereafter, the trip bar 18 returns to its original position by the biasing force of a twist spring (not shown).

  As described above, when the lever 16 rotates in the direction of the arrow LD, the position of the lever connecting shaft 36 moves as shown in FIG. By this movement, the urging force of the main spring 19 against the upper link 14 is reversed, and the position of the lower spring pin 35 on the upper link 14 is moved. When the position of the lower spring pin 35 moves, the connect link 13 is rotated in the direction of the arrow LC as shown in FIG. The movable contact 22 is separated by the rotation of the connect link 13. Although these operations have been described in the first embodiment, the configuration of the present invention is configured to assist the start of the connect link 13 when the movable contact 22 is released by the trip.

A configuration for assisting the start of the connect link 13 will be described with reference to FIGS. 21 and 22. First, FIG. 21 shows a state where the stationary contact 21 and the movable contact 22 are closed, and this state is the same as the ON state of FIG. However, the connection link 13 is provided with a protrusion contact portion 13f, an inflection point 13g, and a contact locking portion 13h. The lever 16 is provided with an opening protrusion 16d.
Accordingly, in the process from the on state of FIG. 21 to the trip state of FIG. 22, when the lever 16 rotates in the direction of the arrow LD, the opening protrusion 16d moves as indicated by the arrow in FIG. During this movement, the opening protrusion 16d comes into contact with the protrusion contact portion 13f of the connect link 13 and works to assist the start of the connect link 13 in the direction of the arrow LC. After the connection link 13 is started, the connection link 13 is rapidly rotated by the urging force of the main spring 19. In order not to hinder this rapid rotation, the opening protrusion 16d is locked to the contact locking portion 13h via the inflection point 13g to be in the state shown in FIG. Note that the state of FIG. 22 is the same as the trip state shown in FIG. As described above, when a trip is caused by an overcurrent, the start of the connect link is assisted to speed up the opening of the movable contact, thereby preventing the circuit breaker from being damaged by an arc or the like.

It is a front view of the circuit breaker which shows embodiment of this invention. It is a perspective view which shows the opening-and-closing contact part which is the principal part of this invention. It is a perspective view which shows the external appearance of a flame | frame. It is a component drawing which shows the detail of a flame | frame. It is a component diagram which shows the detail of a handle | steering-wheel. It is a component diagram which shows the detail of a connection link. It is a component drawing which shows the detail of an upper link. It is a component drawing which shows the detail of a lower link. It is a component drawing which shows the detail of a lever. It is a component diagram which shows the detail of a latch. It is a component diagram which shows the detail of a trip bar. It is a side view for description of an opening / closing contact part. It is a block diagram for description which shows the ON state of an opening-and-closing contact part. It is a block diagram for description which shows the OFF state of an opening-and-closing contact part. It is a block diagram for description of the other part which shows the ON state of an opening / closing contact part. It is a block diagram for description of the other part which shows the OFF state of an opening-and-closing contact part. It is a block diagram for description which shows the trip state of an opening-and-closing contact part. It is explanatory drawing which shows the detail of the sliding groove | channel of a flame | frame. It is explanatory drawing which shows the detail of the engagement hole of a handle | steering-wheel. FIG. 6 is an explanatory configuration diagram of Embodiments 4 and 5. The on state is shown in the configuration diagram for explanation of the sixth embodiment. A trip state is shown in the explanatory configuration diagram of the sixth embodiment.

Explanation of symbols

1 base, 2 cover, 3 opening / closing mechanism, 4 opening / closing contact,
5 Overcurrent trip device, 11 frame, 11b sliding groove, 11k guide piece,
12 handle, 12a engagement hole, 12b bearing hole, 12c engagement protrusion,
13 Connect link, 13d Forced engagement part, 13e Forced rotation part,
13f Protrusion contact portion, 13g Inflection point, 13h Contact locking portion, 14 Upper link,
15 lower link, 16 lever, 16a through hole, 16c locking projection,
16d Opening protrusion, 17 Latch, 18 Trip bar, 19 Main spring,
20 push plate, 21 fixed contact, 21a fixed contact, 22 movable contact,
22a movable contact point, 31 handle shaft, 32 upper spring pin, 32a roller,
35 Lower spring pin, 36 Lever connecting shaft (connecting shaft), 100 Circuit breaker,
111, 112 Frame board.

Claims (6)

A housing formed of a synthetic resin material;
A stationary contact housed in the housing, provided with a fixed contact at one end and connected to the electrical path at the other end, and a movable contact provided with a movable contact opposite the fixed contact;
A push plate connected to the movable contact;
A frame fixed to the housing;
A latch whose one end is pivotally supported by the frame and whose other end is engaged with a trip bar linked to an overcurrent tripping device;
A lever whose one end is pivotally supported by the frame, and a latching projection at the other end is normally locked to the latch;
An upper link having one end rotatably connected to the through hole at the other end of the lever and a lower spring pin at the other end;
A lower link having one end pivotably connected to the upper link via the lower spring pin, one end pivotally supported by the frame, and the other end coupled to the push plate; and A connect link in which the other end of the lower link is rotatably connected to the intermediate portion;
A handle rotatably provided on the upper end side of the frame;
In a circuit breaker that rotates the upper link by driving a main spring engaged with the lower spring pin with the handle to bring the movable contact into and out of contact with the fixed contact.
A circuit breaker configured to obtain an ON state in a state in which the lower link and the upper link are folded so that the other end of the lower link is positioned between one end and the other end of the upper link.   When the fixed contact and the movable contact are welded, the engagement protrusion formed on the handle is engaged with the forced engagement portion provided on the connect link, and the handle is configured not to rotate to the off position. Item 1. The circuit breaker according to item 1.   In a state in which the fixed contact and the movable contact are welded, the engagement protrusion formed on the handle is engaged with the forced rotation portion provided on the connect link, and the connect link is forcibly rotated in the off direction. The circuit breaker according to claim 1.   The lever is provided with an opening protrusion, and the connection link is provided with a protrusion abutting portion with which the opening protrusion abuts.When the trip is started, the opening protrusion is in contact with the protrusion abutting portion of the connect link to start the connect link. The circuit breaker according to any one of claims 1 to 3, wherein the circuit breaker is configured to assist.   The inflection point which changes the action direction by contact | abutting was provided in the middle of the contact contact part of a connection link from the contact of an opening protrusion to the end of a trip. Circuit breaker.   6. The circuit breaker according to claim 4, wherein a contact abutment portion is provided at the projection abutment portion of the connect link to engage the opening projection when the trip ends.

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