JP2592676Y2 - Circuit breaker - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker for detecting an abnormal state of a circuit to cut off the circuit.

[0002]

2. Description of the Related Art In a circuit breaker of this type, an opening / closing mechanism for connecting a handle operable from the outside of a housing to a contact opening / closing operation is supported by a trip link. Various types of mechanisms are conventionally provided. For example, in JP-A-1-246740, a clutch for locking a trip link is urged to rotate in a direction away from a contact portion of an operating body that is spring-biased in a return direction. The urging force to be applied is small, and the force required to operate the operating body is small.

[0003]

According to the above-described circuit breaker, the operating body is spring-biased in the return direction, but the spring is operated so as not to malfunction due to an impact when the handle is turned from on to off. It is necessary to increase the load. In this case, the trip load to be tripped becomes large and the operation of the electric circuit abnormality detecting element cannot be sufficiently transmitted, and there is a problem that it is difficult to trip when an abnormal current flows.

The present invention has been made in view of the above problems, and has as its object to reduce the spring load of a spring that urges an operating body in a return direction, thereby reducing a trip load to be tripped. It is an object of the present invention to provide a circuit breaker that easily trips when an abnormal current flows.

[0005]

According to a first aspect of the present invention, there is provided a circuit breaker having a base and a cover, which are rotatably supported in the housing and are in an abnormal state of an electric circuit. An actuating element having a tripping piece driven against spring bias in accordance with the above and a contact portion interlocked with the tripping piece and being spring-urged in the return direction with respect to the tripping piece; An engaging portion rotatably supported at a different rotation center from the abutting portion and abutting on the abutting portion and sliding substantially horizontally by the rotation of the operating body to be disengaged from the abutting portion; And a clutch rotationally urged in a direction away from the contact portion in a direction substantially perpendicular to the clutch, and a clutch removably engaged with the hook of the clutch so as to apply an urging force in a direction opposite to the rotational urging direction of the clutch. A trip link having an engagement portion for stopping With the support of the lip link, the handle operation and the contact opening / closing operation are connected, a supporting force is applied to the trip link in the direction of locking with the hook portion, and the contact in the closed state is forcibly applied by opening and closing the support of the trip link. An operating body pressing piece that presses the operating body in a return direction when the handle is not in contact with the operating body in an on state and the operating body is in an off state in the circuit breaker that houses the opening and closing mechanism section; Is provided.

A circuit breaker according to a second aspect is configured such that the operating body pressing piece of the first aspect is formed in a substantially L-shape in which the tip thereof bends while pressing the operating body.

[0007]

According to the structure of the first aspect, when the handle is operated from on to off, the operating body pressing piece presses the operating body in the return direction, so that the spring load of the spring for urging the operating body in the return direction. Can be reduced.

According to the second aspect of the invention, in addition to the operation of the first aspect, the operating body pressing piece presses the operating body while gradually bending from a state in which the operating body pressing piece is in contact with the operating body.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. This circuit breaker opens and closes three poles with a single trip mechanism. As shown in FIG. 3, a housing 1 is composed of a base 10 and a cover 11, and each end of the base 10 has Terminal plates 12 and 12 corresponding to the poles are provided, respectively, and a terminal plate extending from the terminal portion 12 on one end side.
A fixed contact 14 is fixed to 13, and a terminal 12 on the other end side is fixed.
The movable contact 20 is connected to the terminal plate 13 extending from the coil via the coil 80 and the flexible wire 88 of the electromagnetic trip element 8. The three poles have the same connection configuration.

A movable contact 20 having a movable contact 24 at one end opposed to the fixed contact 14 has a shaft 21 inserted in the middle thereof.
Is pivotally supported by a movable frame 25 made of synthetic resin, and is contacted in one direction by a contact pressure spring 23 disposed between the pin 22 inserted into the other end and the inner surface of the movable frame 25. It is biased to rotate. The movable frame 25 here is to which the movable contact 20 of each pole is attached.
As a result, it is rotatable with respect to the base 10.

The opening / closing mechanism 2 is provided with a body through a frame 4.
Attached to 1. The frame 4 made of sheet metal, which is fitted to the base 10 and fixed by the cover 11, has a slit 40 cut and raised on both side surfaces and a shaft support boss 41.
And bosses 41b and 41c for stoppers. The handle 3 is attached to the frame 4 via the lever 30. The lever 30 is brought into contact with a bearing notch 33 provided at a lower end edge of both leg pieces inserted into the slit 40 with an outer peripheral surface of the shaft supporting boss 41, so that the lever 30 falls within a predetermined range regulated by the bosses 41b and 41c. The stopper pin 31 is inserted between both leg pieces, a slit recess 32 is provided on the upper end surface, and the handle 3 is pressed into the upper end of the lever 30 from the side surface. , Attached to the lever 30.

The handle 3 is formed of a synthetic resin such as plastic and the like. As shown in FIG. 2, an operating part 37 protruding from the cover 11 to the outside is provided.
The sliding member 38 includes a sliding portion 38 that slides on the inner surface of the sliding member 11 and an operating member pressing piece 39 that is connected from one end of the sliding portion 38 and presses an operating member described later in a return direction. The sliding portion 38 is provided with a display (not shown) on its surface for displaying the on and off states, so that the sliding portion 38 can be hidden in the cover 11 or exposed from the cover 11 every time the operation portion 37 is rotated. ing.
The sliding portion 38 has a cut groove 38a that can be fitted into the lever 30. The operating body pressing piece 39 is formed substantially in an L-shape from one end of the sliding portion 38 so that the distal end thereof bends while pressing the operating body. The operating body pressing piece 39 does not come into contact with the operating body in the on state, and presses the operating body in the return direction in the off state to reduce the spring load of the spring that urges the operating body in the return direction. I can do it.

The trip mechanism comprises a trip link 50, two links 54 and 57, and a spring 36. The trip link 50 is rotatably mounted on the frame 4 via a shaft 45 inserted into a shaft hole 53 at one end thereof, and has a pair of shaft projections 51 on the inner surface side at the other end. Further, an engaging portion 52 protrudes from the other end side, one end of a link 54 is connected to one end side via the shaft projections 51, 51, and the other end of the link 54 is connected by a shaft 56. The link 57 is connected to one end. The other end of the link 57 is connected to the movable contact 20 via the shaft 21.

A spring 36 composed of a tension coil spring acting for opening the pole is bridged between the connecting shaft 56 of the two links 54 and 57 and the pin 35 arranged in the recess 32 of the lever 30. Have been.

A clutch 6 and an operating body 7 are further mounted on the frame 4. The clutch 6 is rotatably supported by a shaft 46 inserted into the frame 4 and a shaft hole 60 at the lower end, and an opening is formed on the trip link 50 side. A hook portion 62 that engages with the engaging portion 52 of the link 50 is provided. Further, an engaging portion 63 and a protrusion 65 are provided on the upper end edge of the clutch 6.

The operating body 7 is composed of a metal rod 70 and a molded part 71 made of a synthetic resin which is formed by coating around the metal rod 70. The molded part 71 includes a plurality of trip pieces 72. , A contact portion 73 protruding in the opposite direction to the tripping piece 72, and a spring receiving protrusion.
74, push-up protrusion 75 that projects in the same direction as the contact part 73, interlocking protrusion
As shown in FIG. 3, the operating member pressing piece 39 of the handle 3 presses the push-up projection 75 in the off state to urge the handle 3 in the return direction, as shown in FIG. This actuator 7 is the frame
4 and is rotatably supported in a pair of U-shaped bearing grooves 47, 47.

The two ends of a spring 66 composed of a torsion coil spring mounted on the shaft 46 for pivotally supporting the clutch 6 are in contact with the clutch 6 and the spring receiving projection 74 of the operating body 7, The clutch 6 and the operating body 7 having different rotation centers only by the spring 66 are urged in the counterclockwise direction in FIG. The operating body 7 is pushed into the bearing groove 47 by the bias of the spring 66,
Is prevented by the spring 66.
After the cover 11 is attached, the operating body 7 is further prevented from coming off by a retaining projection (not shown) attached to the cover 11. Actuator 7 using spring 66 in bearing groove 47
By pressing down, the actuating body 7 that doubles as an interlocking rod
By enabling the rotation bias of with a single spring 66,
The aim is to reduce the number of parts.

The other tripping pieces 72 and the interlocking projections 78 and 79 provided on the operating body 7 are used to drive other tripping members such as an earth leakage tripping member and an external voltage tripping member, or to drive an auxiliary contact. However, the description of these is omitted here.

The electromagnetic trip element 8 includes a coil 80,
A yoke 82, an oil dash pot 81, and an armature 83 supported by one end of the yoke 82 and urged by a return spring 84 are formed.

In the off state shown in FIG. 3, the armature 83 of the electromagnetic trip element 8 is separated from the tip of the oil dash pot 81 by the bias of the return spring 84. The position of the shaft 46 that pivotally supports the clutch 6 by receiving the urging force of the spring 36 via the link 54 by the engaging portion 52 of the trip link 50, and the positional relationship between the hooking portion 62 and the engaging portion 52. As a result, the engaging portion 52 is urged to rotate counterclockwise by the spring 66, and at the same time, the contact portion 73 of the operating body 7 contacts the engaging portion 63 of the clutch 6. The rotation of the clutch 6 in the clockwise direction is stopped. Further, the pair of links 54 and 57 in the trip mechanism are folded by the bias of the spring 36, and the contact block, which is rotatable about the shaft 26, is pulled up to move the movable contact. The 20 movable contacts 24 are separated from the fixed contacts 14. The operating body 7 is an operating body pressing piece of the handle 3.
It is biased in the return direction by 39.

In this state, if the handle 3 is moved to the left in the figure to cause the handle 3 to rotate about the boss 41 of the frame 4, the spring 36 initially moves around the shaft 56. Although it only turns, when the spring 36, that is, the line connecting the pin 35 at both ends of the spring 36 and the shaft 56 exceeds the position of the shaft projection 51 connecting one end of the link 54 and the trip link 50,
The shaft 56 is pulled to the left in the drawing by the bias of the spring 36, and FIG.
The links 54, 57 extend as shown in FIG. For this purpose, the contact block rotates counterclockwise in the drawing, and the movable contact
20 movable contacts 24 are brought into contact with the fixed contacts 14,
At this time, the bias by the contact pressure spring 23 is applied to the contact portion. At this time, the operating body pressing piece 3 of the handle 3
9 is not in contact with the operating body 7.

If the handle 3 is moved in the reverse direction from the on state, when the spring 36 passes over the shaft projection 51,
It returns to the state shown in FIG. In both the on and off states, the trip link 50, the clutch 6 and the operating body 7,
That is, the members around the latch engagement portion between the engagement portion 52 and the hook portion 62 do not move at all. Also, the operating body pressing piece 39 of the handle 3
Presses the operating body 7 in the return direction when in the OFF state shown in FIG. 3, and presses the operating body 7 when in the ON state shown in FIG.
Do not abut.

In the ON state shown in FIG. 4, an overcurrent flows through the coil 80 of the electromagnetic trip element 8 and the armature 83 rotates against the spring 84, so that the tripping piece of the operating body 7 is released. When the armature 83 hits the armature 72 to rotate it, or when the test button 19 pushes the test tripping piece 76 to rotate the armature 7, the state shifts to the trip state shown in FIG.

That is, by the rotation of the operating body 7,
The contact portion 73 separates from the engagement portion 63 of the clutch 6 and the clutch 6
When there is no hold on the clutch, as described above, the clutch
6 is greater than the bias in the counterclockwise direction in the figure by the spring 66,
Since the clockwise urging received from the spring 36 via the link 54 and the trip link 50 is stronger, the clutch 6 first rotates clockwise, and the engaging portion 52 of the trip link 50 When the latch 6 is released from the hook portion 62 and released, the clutch 66 rotates counterclockwise by the bias of the spring 66 until the stopper 6a of the clutch 6 comes into contact with the stopper 42 provided on the frame 4. When this trip state occurs, the operating body 7 rotates in a direction to bend the operating body pressing piece 39, but the operating body pressing piece 39 is formed in a substantially L-shape from its base end to its distal end to increase elasticity. Since it is provided, the operating body pressing piece 39 is hard to be broken.

On the other hand, the trip link 50, which has been unlatched with the clutch 6, has a spring 54
Due to the urging by the lever 36, the lever 30 rotates counterclockwise until the contact surface 50a of the trip link 50 contacts the protrusion 4a of the frame 4 and the lever 30 rotates clockwise by the spring 36, and the stopper pin 31 trips. Contact surface 50a of link 50
The lever 30 and the trip link 50 stop relative to the frame 4 at the time when the contact occurs. At this time, the trip link 50 pushes the push-up protrusion 75 of the operating body 7 clockwise. When the trip link 50 rotates, the shaft projection 51
At the time when the spring 36 is moved to the left of the drawing, the spring 36 is reversed, the links 54 and 57 are folded, and the movable frame 25 rotates clockwise about the shaft 26, and the movable contact 24 of the movable contact 20 is rotated. Moves away from the fixed contact 14. The rotation of the movable frame 25 is stopped when the stopper 25a contacts the U-shaped groove wall (not shown) of the base 10.

The handle 3 is stopped by the action of the spring 36 at a position determined from the stop position of each member described above.
Further, since the engaging portion 52 of the trip link 50 pushes up the tip of the push-up projection 75 of the operating body 7, the operating body 7 is held in the state shown in FIG.

Here, when the operating body 7 rotates to start the trip operation, the force F1 by the above-mentioned moment and the rotational bias of the operating body 7 by the spring 66 are applied between the operating body 7 and the clutch 6. Since the force F2 is acting, the difference F3 between the forces F1 and F2 (F3 =
Only F1 = F2) acts as a resistance to rotating the actuator 7. For this reason, the tripping force is reduced.

Next, the reset operation will be described. FIG.
When the handle 3 is moved to the right in the drawing from the trip state shown in FIG. 6, the stopper link 31 of the lever 30 pushes the handle 3 to rotate the trip link 50 clockwise as shown in FIG. In a state where the engaging portion 52 is located below the push-up protrusion 75 of the operating body 7, the clutch portion 6 abuts against one surface of the protrusion 65 of the clutch 6, and slides on this surface to oppose the clutch 6 against the spring 66. Rotate clockwise in the figure. At this time, the engaging portion 52 of the trip link 50 maintains the state in which the push-up protrusion 75 of the operating body 7 is still pushed up.
63 goes under the contact portion 73 of the operating body 7. And trip link 50 with this undercut
The lifting of the operating body 7 by the projection 52 of the
7 rotates counterclockwise, and the lower surface of the projection 75 of the operating body 7 comes into contact with the upper end of the projection 63 of the clutch 6, and the state shown in FIG. 7 is obtained. If the clockwise rotation of the trip link 50 proceeds further,
The engaging portion 52 of the trip link 50 slides on the surface while the hook portion
62 enters the opening of the clutch 6 with the upper edge. For this reason, the clutch 6 is released from the pressing from the engaging portion 52, and rotates counterclockwise in the drawing while sliding the engaging portion 63 to the lower surface of the contact portion 73 by the bias of the spring 66. As a result, the lower surface of the push-up protrusion 75 of the operating body 7 comes into contact with the upper end of the protrusion 65 of the clutch 6 and stops, and the state shown in FIG.

When the hand is released from the handle 3 in the state shown in FIG. 8, the handle 3 returns to the center by the urging force of the spring 36. At this time, the force of the spring 36 is applied to the link 54. The trip link 50 received via this also starts rotating around the shaft 45 in the counterclockwise direction in the figure. Then, with the rotation of the trip link 50, the engaging portion 52 comes into contact with the hook portion 62 of the clutch 6, and the clutch 6 is rotated clockwise in the drawing against the spring 66, and by this rotation, clutch
The engagement portion 63 of FIG. 6 contacts the lower surface of the contact portion 73, and returns to the off state shown in FIG. The operation force required for resetting and returning to the off state is very light, and stable resetting can be performed.

The length and width of the operating body pressing piece may be appropriately designed in accordance with the pressing force of the operating body.

[0031]

According to the circuit breaker of the present invention, when the handle is operated from on to off, the operating body pressing piece presses the operating body in the return direction, thereby urging the operating body in the return direction. The spring load of the spring can be reduced, and the trip load can be reduced when the trip current is reduced and an abnormal current flows.

According to the circuit breaker of the second aspect, the operating body pressing piece presses the operating body while flexing gradually from the state in which it comes into contact with the operating body. The pressing piece is less likely to break.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an embodiment of the present invention.

FIG. 2 is a rear perspective view showing the handle of FIG. 1;

FIG. 3 is a cross-sectional view of the device of FIG. 1 in an off state.

FIG. 4 is a cross-sectional view of FIG. 1 when turned on.

FIG. 5 is a sectional view of the device of FIG. 1 at the time of a trip.

FIG. 6 is an explanatory diagram showing a state in which the reset operation of FIG. 5 is performed.

FIG. 7 is an explanatory diagram showing a state in which the reset operation of FIG. 6 is further performed.

FIG. 8 is an explanatory diagram showing a state in which the reset operation of FIG. 7 is further performed.

FIG. 9 is an enlarged sectional view showing the operating body, clutch and trip link of FIG. 3;

[Description of Signs] 1 Housing 2 Opening / closing mechanism 3 Handle 5 Trip link 6 Clutch 7 Operating body 10 Base 11 Cover 39 Operating body pressing piece 52 Trip link engaging section 62 Hooking section 63 Clutch engaging section 72 Release strip 73 Contact part

Claims (2)

(57) [Scope of request for utility model registration] 1. A tripping piece which is formed by a base and a cover and is rotatably supported in the housing and driven against spring bias in response to an abnormal state of an electric circuit, and a tripping piece. An operating member having a contact portion interlocked with the operating member and being spring-biased in the return direction with respect to the tripping piece, and rotatably supported at a rotation center different from that of the operating member to contact the contact portion and A clutch which is provided with an engaging portion which slides substantially horizontally by the rotation of the operating body and is disengaged from the contact portion, and a hook portion which cooperates with the engaging portion, and which is urged to rotate in a direction substantially perpendicularly away from the contact portion. A trip link having an engaging portion that is releasably locked to a hook portion of the clutch so as to apply an urging force in a direction opposite to the rotational urging direction of the clutch; And the contact switching operation An open / close mechanism for applying a supporting force to the trip link in a direction to be engaged with the hook portion and forcibly opening a contact in a closed state by opening and supporting the trip link. A circuit breaker comprising: a handle of the opening / closing mechanism unit provided with an operating body pressing piece that does not abut against the operating body in an on state and presses the operating body in a return direction in an off state. 2. The circuit breaker according to claim 1, wherein the operating body pressing piece is formed in a substantially L-shape in which a tip thereof bends while pressing the operating body.