JP3552867B2 - Circuit breaker - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a circuit breaker, and more particularly to a low-cost, low-cost, high-assembly, and highly-reliable circuit breaker that can rotate only in an appropriate angle range when rotating a hook.
[0002]
[Prior art]
A circuit breaker is a switch for automatically shutting off a circuit when a short circuit fault occurs in a transmission / distribution line, a substation bus or equipment, etc., and is also used for opening and closing the circuit in normal times.
[0003]
FIG. 5 shows a structural diagram of a conventional circuit breaker.
The circuit breaker includes a main circuit, an opening / closing trip mechanism 8 ', a trip device 9', and the like.
[0004]
The main circuit includes a power-supply-side fixed contact stand 1 ', a fixed contact 2', a movable contact 3 'opposed thereto, a movable contact stand 4', a load-side fixed contact stand 5 ', and the like.
[0005]
The movable contact base 4 'is held on a contact shaft 6' via a contact spring 7 ', and the contact shaft 6' is connected to the opening / closing trip mechanism 8 'and rotated to connect the contact of the main circuit. It has a structure that opens and closes.
[0006]
The tripping device 9 'is linked to the opening / closing tripping mechanism 8', and trips the main circuit when the tripping device 9 'operates. When the tripping device 9 'operates, its mechanical output trips the latch of the opening / closing tripping mechanism 8' to operate the opening / closing tripping mechanism 8 'to move the movable contact stand 4', and the main circuit Open immediately.
[0007]
The main circuit element and the main circuit switching element are housed in the main body case 10 'and the main body cover 11' to constitute a circuit breaker.
[0008]
The internal configuration of the opening / closing tripping mechanism 8 'will be described with reference to FIG.
The opening / closing trip mechanism 8 'includes a fixed frame 13', a handle link 14 ', a hook 15', a hook pin 16 ', a link upper / lower pin 17', an upper link 18 ', a lower link 19', a trip fitting 20 ', and a trip fitting. It comprises a pin 21, a trip spring 22, a trip link 23 ', a trip link shaft 24', and a trip link pin 25 '.
[0009]
The operation handle 12 'is connected to a handle link 14', and the handle link 14 'rotates around one point of the fixed frame 13'.
[0010]
The lower link 19 'is connected to the movable contact base 4, the lower link 19' and the upper link 18 'are connected by link upper and lower pins 17', and the link upper and lower pins 17 'and the handle link 14' are connected to the drive spring 25. ′, The upper link 18 ′, the lower link 19 ′, and the drive spring 26 ′ are interlocked via the link upper and lower pins 17 ′ .
[0011]
The hook 15 'is connected to the fixed frame 13' by a hook pin 16 ', and rotates around the hook pin 16'.
[0012]
Further, the upper link 18 ′ is connected to the hook upper embossing portion 27 ′, and rotates around the hook upper embossing portion 27.
[0013]
Since the trip fitting 20 'is connected to the fixed frame 13' by the trip fitting pin 21 'together with the trip spring 22', the trip fitting 20 'rotates around the trip fitting pin 21'. Then, the trip fitting 20 exerts a force to rotate to the load side by the trip spring 22 '.
[0014]
Since the trip link 23 'is connected to the fixed frame 13' by the trip link pin 25 ', it rotates around the trip link pin 25'.
[0015]
The hook 15 'is lifted upward by the drive spring 26' via the upper link 18 'and tries to rotate in the direction toward the power source around the hook pin 16', but the tip of the hook 15 'is the trip fitting 20'. , The rotation of the hook 15 'is stopped. Further, the trip fitting 20 'attempts to release the engagement with the hook 15' by the trip spring 22 ', but its rotation is stopped by the trip link 23'.
[0016]
In this mechanism, when the trip link 23 'is rotated by the trip device 9', the trip link 23 'and the trip fitting 20' are unlatched, the trip fitting 20 'is rotated, and the trip fitting 20' and the hook are rotated. The latch 15 'is disengaged and the hook 15' rotates, thereby moving the movable contact base 4 'and opening the main circuit.
[0017]
[Problems to be solved by the invention]
However, the above prior art does not consider the arrangement of the hook 15 ′, the upper link 18 ′, the lower link 19 ′ and the fixed frame 13 ′ and the stoppers of the hook 15 ′ and the lower link 19 ′. 'And the lower link 19' are difficult to stop at predetermined positions, and it is necessary to prepare new parts. According to the present invention, the rotation of the hook and the lower link can be easily stopped at a predetermined position without using a new part, and the space is effectively used.
[0018]
The present invention relates to a low-cost, low-cost, high-assembly, and highly-reliable circuit breaker with an appropriate rotation angle of a hook or a lower link.
[0019]
[Means for Solving the Problems]
The present invention has the power supply side stationary contact base, the opposing contact, the movable contact base, a main circuit having an overcurrent relay unit and the load side stationary contact, stationary frame, a link on which is connected to the hook and the hook, In a circuit breaker including an opening / closing trip mechanism for rotating a movable contact base to open / close a circuit contact and a trip device for operating the opening / closing trip mechanism, the hook is provided with the hook The circuit breaker is disposed between a fixed frame having a stopper and the upper link, and the lower link is disposed in a gap below the hook .
[0021]
The present invention also has a lower link, and the lower link is a circuit breaker disposed between the fixed frame and the upper link.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described.
One embodiment of the circuit breaker of the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view of an embodiment of the circuit breaker of the present invention, FIG. 2 is an explanatory view of an embodiment of the circuit breaker of the present invention, and FIG. 3 is an opening / closing trip mechanism in the circuit breaker of the present embodiment. FIG. 4 is an explanatory view of an arrangement example of fixed frames and the like in the circuit breaker of the present embodiment.
[0024]
The circuit breaker of this embodiment is a three-pole circuit breaker. Each pole is a power-side fixed contact block 1 electrically connected to a power-side terminal and a load-side fixed contact block electrically connected to a load-side terminal. A load-side fixed contact table 5 as a conductor is provided at a substantially point-symmetric position with respect to the rotation center of the movable contact table 4 as a movable conductor rotatably held. , The load-side fixed contact stand 5 and the movable contact stand 4 form a main circuit.
[0025]
The power supply fixed contact base 1 has a power supply fixed contact 2 at a position opposed to the power supply movable contact 3, and the load fixed contact base 5 has the load fixed contact 2 at a position opposed to the load movable contact 3. Have.
[0026]
The movable contact stand 4 has a power supply side movable contact and a load side movable contact 3 at point symmetrical positions with respect to the rotation center thereof, and is held on a contact shaft 6 via a contact spring 7. It is structured to open and close the contacts of the main circuit by connecting and rotating with the opening / closing trip mechanism 8.
[0027]
The movable contact stand 4 is mechanically connected to an opening / closing tripping mechanism 8 as an opening / closing tripping mechanism, and when the opening / closing tripping mechanism 8 is turned on, the power-side fixed contact stand 1 and the load-side fixed contact stand 5 are moved. Is rotated to a position where the is electrically connected.
[0028]
This main circuit is housed in a main circuit case formed of an insulator. In the state where the main circuit is housed in the main circuit case, the power supply side terminal portion of the power supply side fixed contact block 1 and the load side terminal portion of the load side fixed contact block 5 protrude from the main circuit case. It is located in the circuit case and is electrically insulated from the outside. A holding member for rotatably holding the movable contact stand 4 in the main circuit case is also formed of an insulating material.
[0029]
An arc chute (arc extinguishing device) is provided near the contacts of the power-supply-side fixed contact stand 1, the load-side fixed contact stand 5, and the movable contact stand 4 in the main circuit case to suck and cool an arc generated at the time of interruption. Further, in this embodiment, an arc discharge port for discharging the cooled arc gas is provided in the main circuit case.
[0030]
The main circuit case is arranged in parallel for three poles, and the holding members are connected so that the movable contact blocks 4 of the respective poles can be opened and closed substantially simultaneously.
[0031]
In this embodiment, the opening / closing trip mechanism 8 is mounted on the upper outside of the main circuit case at the center pole, and is connected to a rotating arm of an insulator coaxially connected to the rotation axis of the holding member. As a result, the opening / closing trip mechanism 8 is provided outside the main circuit case and connected to the movable contact stand 4 via an insulator, so that even when a voltage is applied to the main circuit, the opening / closing trip mechanism 8 is provided. No voltage is applied to.
[0032]
The opening / closing trip mechanism 8 is operated by the operation handle 12 to manually turn on / off the main circuit, and when the current of the main circuit exceeds a predetermined value, the tripping device 9 shuts off the main circuit. Is
[0033]
The trip device 9 includes a fixed core disposed in the vicinity of the load-side fixed contact stand 5, a magnetic circuit substantially rotatably held at one end and substantially closed together with the fixed core at a position facing the fixed core. And a transmission lever for transmitting the operation of the movable core to the opening / closing trip mechanism 8.
[0034]
When the current of the main circuit increases and exceeds a predetermined value (about 10 to about 20 times the rated current), the magnetic flux generated around the conductor of the load-side fixed contact block 5 increases, and the movable core is fixed. The core is sucked and moved, and the transmission lever contacts the trip link shaft 24 to rotate the trip link 23, and the main circuit is opened by the tripping operation of the opening / closing tripping mechanism 8. As a result, the circuit is cut off and a large overcurrent can be prevented from flowing to the load side.
[0035]
In the present embodiment, a current transformer for detecting a current flowing through the main circuit is provided at a portion of the main circuit from the main circuit case to the load terminal of the load-side fixed contact block 5, and the output of the current transformer is a current transformer. It is supplied to an overcurrent detection circuit provided above the container.
[0036]
The overcurrent detection circuit generates an output based on a predetermined time limit characteristic in a range of about 1.1 times to about 20 times the rated current. The output of the overcurrent detection circuit is supplied to a magnetic trip device (not shown) that releases the movable core attracted by the permanent magnet by reverse excitation. As such a magnetic trip device, for example, one described in Japanese Patent Application No. 8-62449 can be used.
[0037]
When released, the movable core of the magnetic trip device contacts the trip link shaft 24 to rotate the trip link 23, and the main circuit is opened by the tripping operation of the opening / closing trip mechanism 8. As a result, the circuit is shut off and the overcurrent can be prevented from flowing to the load side.
[0038]
The main circuit case, the opening / closing trip mechanism 8, the trip device 9, the current transformer, the overcurrent detection circuit, and the magnetic trip device are housed in a housing having a main body case 10 and a main body cover 11, and are opened / closed. The knob, the power supply side terminal and the load side terminal of the operation handle 12 mounted on the mechanism section 8 are exposed outside the housing.
[0039]
Further, in the present embodiment, the main circuit is formed by the power-supply-side fixed contact block 1, the load-side fixed contact block 5, and the movable contact block 4. However, the power-supply-side fixed contact block as used in the prior art is connected to the load. The main circuit formed by the movable contact block connected to the side may be opened and closed by a switching mechanism.
[0040]
An example of the structure of the opening / closing trip mechanism 8 will be described with reference to FIG.
The opening / closing tripping mechanism 8 includes a hook stopper 13A formed by bending, a fixed frame 13 provided with a lower link stopper 13B formed by stamping and a projection 28, a handle link 14, a hook 15, a hook pin 16, It comprises a link upper / lower pin 17, an upper link 18, a lower link 19, a trip fitting 20, a trip fitting pin 21, a trip spring 22, a trip link 23, a trip link shaft 24, and a trip link pin 25.
[0041]
The operation handle 12 is connected to a handle link 14, and the handle link 14 rotates around one point of the fixed frame 13.
[0042]
The fixed frame 13 has a U-shaped portion and a flat plate-shaped portion, and the both ends of the U-shape are caulked to a flat plate-shaped component to form a substantially rectangular cross-section frame. Formed in the body.
[0043]
The hook 15, the upper link 18, and the lower link 19 are mounted in the frame of the fixed frame 13, respectively.
[0044]
The hook 15 is formed in a U-shape, and the ends of both sides of the U-shape are rotatably supported by the frame body of the fixed frame 13, and a portion connecting the two sides of the U-shape is engaged with the trip fitting 20. Projections for rotatably locking the upper link 18 are formed inside the substantially central portions of both sides of the U-shape.
[0045]
The hook 15 is rotatably connected to the fixed frame 13 by a protrusion 28, and the protrusion 28 becomes the center of rotation of the hook.
[0046]
The upper link 18 is rotatably connected to the hook upper embossing portion 27 and rotates around the hook upper embossing portion 27.
[0047]
Since the lower link 19 is connected to the movable contact stand 4, the lower link 19 and the upper link 18 are connected by link upper and lower pins 17, and the link upper and lower pins 17 and the handle link 14 are connected by a drive spring 25. The upper link 18, the lower link 19, and the drive spring 26 are linked via the link upper and lower pins 17.
[0048]
The upper link 18 and the lower link 19 are each formed in a substantially U-shape, and the vicinity of the bottom of the U-shape is bent substantially 90 degrees to have a U-shaped cross section.
[0049]
The upper link 18 and the lower link 19 are rotatably connected near the bottom of the U-shape such that the bent portions face in opposite directions. The upper link 18 and the lower link 19 of the present embodiment may be manufactured by a method of combining the upper link 18 and the lower link 19 in a pressing process described in Japanese Patent Application No. 8-246170.
[0050]
The upper link 18 and the lower link 19 are combined such that the upper link 18 is inside and the lower link 19 is outside, and both sides of the U-shape of the upper link 18 are rotatable inside the hook 15 on a projection formed on the hook 15. Engages.
[0051]
Both sides of the U-shape of the lower link 19 are rotatably locked to a rotating arm of an insulator connected to the holding member of the movable contact block of the main circuit. Accordingly, the positional relationship between the upper link 18, the lower link 19, and the hook 15 with respect to the fixed frame 13 is such that the upper link 18 is the innermost, the lower link 19 and the hook 15 are positioned outside the inner frame, and the fixed frame 13 is the outermost. Become.
[0052]
Since the trip fitting 20 is connected to the fixed frame 13 by the trip fitting pins 21 together with the trip spring 22, the trip fitting 20 rotates around the trip fitting pins 21. Then, a force rotating to the load side acts on the trip fitting 20 by the trip spring 22.
[0053]
Since the trip link 23 is rotatably connected to the fixed frame 13 by the trip link pin 25, the trip link 23 rotates around the trip link pin 25.
[0054]
The hook 15 is turned upward by the drive spring 26 via the upper link 18 and tries to rotate in the power supply side direction around the protrusion 28. However, the tip of the hook 15 is engaged with the trip fitting 20. The rotation of the hook 15 is stopped. Further, the trip fitting 20 attempts to release the engagement with the hook 15 by the trip spring 22, but the rotation is stopped by the trip link 23.
[0055]
When the trip link 23 is rotated by the trip device 9, the latch between the trip link 23 and the trip fitting 20 is released and the trip fitting 20 is rotated, and the latch between the trip fitting 20 and the hook 15 is released and the hook 15 is rotated. Then, the movable contact table 4 is moved accordingly, and the main circuit is opened.
[0056]
The fixed frame 13 has a hook stopper 13A formed by bending, a lower link stopper 13B formed by stamping, and a projection 28 serving as a rotation center of the hook 15 inside the frame. The hook stopper 13A and the lower link stopper 13B are located on opposite sides with respect to the projection 28, and the projecting dimension of the hook stopper 13A into the frame is formed to be larger than the projecting dimension of the lower link stopper 13B into the frame.
[0057]
An example of the arrangement of the fixed frame 13, the hook 15, the upper link 18, and the lower link 19 in the circuit breaker of the present embodiment will be described with reference to FIGS. 4A and 4B.
[0058]
The hook 15 is arranged and connected between the fixed frame 13 and the upper link 18. Since a gap is formed below the hook 15, the lower link 19 is disposed there.
[0059]
Since the hook 15 is disposed between the fixed frame 13 and the upper link 18, if a bent portion is formed in the fixed frame 13, the hook 15 can be used as a hook stopper 13 </ b> A. Since 19 can be arranged, the space is effectively used. Then, by using the stamping process, a projection can be easily formed on the fixed frame 13, and the projection can be used as the stopper 13B of the lower link 19, so that there is no need to prepare another component, and the hook 15 can be used. And the lower link 19 can be stopped at a predetermined position.
[0060]
Further, since the stopper 13A of the hook 15 is formed by bending, it is easy to set the thickness in the direction of receiving a force when the hook 15 comes into contact with the hook 15, and sufficient strength as the stopper of the hook 15 can be obtained.
[0061]
Since the hook 15 and the lower link 19 are provided adjacent to the fixed frame 13 and at a short distance from the frame 13, when the stoppers 13A and 13B of the hook 15 and the lower link 19 are viewed as cantilever beams, the contact position is the fulcrum. , The amount of deformation (deflection) at the time of contact can be reduced, metal fatigue is reduced, and the life is prolonged.
[0062]
As described above, in this embodiment, the number of parts is reduced, the cost is reduced, the assemblability is improved, and the reliability is improved.
[0063]
Although the method of forming the projections was stamping in the present embodiment, the present invention is not limited to this. A member serving as a projection is separately formed, and plastic deformation such as caulking, screw or riveting, resistance welding, or the like is performed. It may be fixed to the fixed frame by welding, bonding, or a combination thereof.
[0064]
【The invention's effect】
As described above, according to the present invention, the rotating hook or lower link can be stopped at a predetermined position without using a new part, and can be prevented from rotating at an angle larger than that. The circuit breaker can also be effectively used, is inexpensive, has good assemblability, and has high reliability.
[Brief description of the drawings]
FIG. 1 is a perspective view of one embodiment of a circuit breaker of the present invention.
FIG. 2 is an explanatory diagram of one embodiment of the circuit breaker of the present invention.
FIG. 3 is an explanatory diagram of an example of a switching trip mechanism in the circuit breaker of the present invention.
FIG. 4 is an explanatory diagram of an example of an arrangement of fixed frames and the like in the circuit breaker of the present invention.
FIG. 5 is an explanatory diagram of a conventional circuit breaker.
FIG. 6 is an explanatory view of a switching mechanism in a circuit breaker according to the related art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Power supply side fixed contact stand 2 Fixed contact 3 Movable contact 4 Movable contact stand 5 Load side fixed contact stand 6 Contact axis 7 Contact spring 8 Opening / closing tripping mechanism section 9 Tripping device 10 Main body case 11 Main body cover 12 Operation handle 13 Fixed frame 13A Hook stopper 13B Lower link stopper 14 Handle link 15 Hook 16 Hook pin 17 Link vertical pin 18 Upper link 19 Lower link 20 Trip bracket 21 Trip bracket pin 22 Trip spring 23 Trip link 24 Trip link shaft 25 Trip link pin 26 Drive spring 27 Hook Upper stamping part 28 Projection

Claims (1)

Power supply side stationary contact base, the opposing contact, the movable contact base, a main circuit having an overcurrent relay unit and the load side stationary contact, stationary frame has a link on which is connected to the hook and the hook, the movable contact base In a circuit breaker having an opening / closing trip mechanism for turning on / off the circuit contact by rotating, and a trip device for operating the opening / closing trip mechanism,
The circuit breaker, wherein the hook is disposed between a fixed frame having a stopper for the hook and the upper link, and a lower link is disposed in a gap below the hook .

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