JP2007242597A - Gas-blast power-breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve on reliability of a gas-blast power-breaker through protection of an input control mechanism. <P>SOLUTION: The gas-blast power-breaker is provided with a breaking spring 26 and a making spring 28 opening and closing a contact, a rotating shaft 4 fixed on a concentric line with a main lever 5 and supported in free rotation inside a case 1, a gear wheel 52 fixed to the rotating shaft 4 with a partial gear 53 fitted at a part in a peripheral direction, and a pinion 51 meshing with the gear wheel and the partial gear. When the pinion continues to rotate after the making spring stores energy, meshing of the gear wheel and the pinion is released. A making spring link 27 connects the making spring and the gear wheel. An angle made by an axis line of the making spring link and an axis X1 when the energy storing of the making spring is completed is within a range of 0° and around 10°, with reference to the axis X1 passing an axial center of the rotating shaft and parallel with an action direction of the making spring. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power gas circuit breaker, and more particularly to a power gas circuit breaker suitable for high voltage specifications such as a substation and a switching station.

  Another example of a conventional closing spring energy storage device is described in Patent Document 2. In the spring operating mechanism described in this publication, a closing spring energy storage device includes a large gear partially missing and a small gear that is rotationally driven by a meshing drive source. Two synchronous claws capable of swinging are provided in the missing tooth portion of the large gear, and immediately after the completion of the energization of the closing spring, the small gear and the first tooth of the synchronous claw are engaged, and the second tooth of the synchronous claw starts closing operation. Immediately bite. As a result, even if the electric motor continues to rotate after the completion of the charging of the closing spring, it is possible to avoid applying an excessive load from the small gear to the large gear due to the swinging of the synchronous claw of the large gear. Prevents loading.

  Another example of the closing spring energy storage device is described in Patent Document 3. In the spring operating mechanism described in this publication, a clutch drive element is provided on the same axis as the small gear. Since the clutch is disengaged at the moment when the charging of the closing spring is completed and the driving force from the motor is not transmitted to the small gear, the small gear and the large gear are not driven even if the motor continues to rotate after the charging of the closing spring is completed. . This prevents an excessive load from being applied to the making control mechanism.

JP 2001-28391 A Japanese Patent No. 2529309 Japanese Patent No. 3644187

  However, in the spring operation mechanism described in Patent Document 1, since the large gear and the small gear are always meshed with each other, when an abnormal state occurs in which the electric motor and the small gear continue to rotate after the energy accumulation of the closing spring is completed. An excessive load is applied to the closing control mechanism. As a result, the mechanical parts may be damaged. If a situation occurs in which the small gear is manually rotated, the operator may continue to operate without noticing, and an excessive load may be applied to the closing control mechanism.

  In the spring operation mechanism described in Patent Document 2, it is possible to prevent an excessive load from being applied to the closing control mechanism after the closing spring accumulation is completed. However, since a collision load is repeatedly generated on the synchronous claw, the strength of the synchronous claw must be increased. Further, when the large gear and the small gear are meshed again in the next closing operation, considerable noise is generated as the tooth surfaces mesh.

  The spring operating mechanism described in Patent Document 3 is provided with a clutch to prevent an excessive load from being applied to the closing control mechanism after the closing spring accumulation is completed. However, it takes a lot of time to adjust the cam mechanism that defines the timing for disengaging the clutch. Further, the cam mechanism is disposed between the large gear and the frame, which is difficult to visually inspect from the outside, and requires a great number of man-hours when the clutch is repaired and replaced.

  The present invention has been made in view of the above problems of the prior art, and an object thereof is to protect the closing control mechanism and improve the reliability of the gas circuit breaker. Another object of the present invention is to eliminate the need for adjustment of the protection mechanism of the input control mechanism and facilitate replacement. Another object of the present invention is to monitor the state of the protection mechanism during charging of the closing spring and detect an abnormality.

  A feature of the present invention that achieves the above object is a power gas circuit breaker that opens and closes a contact having a fixed contact and a movable contact by a stored force of a breaking spring and a closing spring to switch between cutting off and turning on power. An accumulating means for accumulating a spring is provided, the accumulating means has a small gear, a large gear and a partial gear meshing with the small gear, and the large gear is formed in a shape in which a part of the circumferential direction is missing. The partial gear having lower meshing strength than the large gear is attached to the missing portion. And in this feature, it is preferable to set so that the teeth of the partial gear are broken earlier than the teeth of the large gear and the meshing with the small gear is released.

  Another feature of the present invention that achieves the above object is to provide a shut-off unit that opens and closes a contact having a fixed contact and a movable contact to switch power off and on, a shut-off spring that opens and closes the contact, a closing spring, and a closing A power gas circuit breaker equipped with a closing spring accumulator that transmits the driving force of the spring to the cam to store the blocking spring and stores the closing spring with an electric motor and a gear train. A rotary shaft rotatably supported in the housing, a large gear fixed to the rotary shaft and having a partial gear attached to a part of the circumferential direction, a small gear meshing with the large gear and the partial gear, A closing spring link for connecting the spring and the large gear, and when the energy storage of the closing spring is completed with reference to an axis X1 passing through the axis of the rotating shaft and parallel to the operating direction of the closing spring. Angle between axis and axis X1 is 0 ° to about 10 ° It is in the range.

  In any one of the above features, the partial gear is preferably configured to be detachable from the large gear, and the teeth of the partial gear that is detachable from the large gear must be the same module and pitch as the teeth of the large gear. Further, the missing part of the large gear is a groove, and it is preferable that the partial gear is fitted into the groove and then screwed. The large gear and the partial gear may be made of different materials. The width direction length of the formed part may be narrower than the tooth width of the large gear. A slit extending in the width direction may be formed in the tooth base surface of the partial gear, and a hole for fastening with the large gear may be formed in a portion where the teeth of the partial gear are not formed. The tooth surface strength of the teeth on the end side may be larger than that of the other teeth.

  Another feature of the present invention that achieves the above object is that a photoelectric sensor is arranged in the housing so as to detect teeth of the large gear and the partial gear, and an arithmetic processing unit and display means capable of displaying an abnormal state are provided. By preparing. In this feature, the output waveform of the photoelectric sensor in the reference state in which the teeth of the partial gears are not damaged is stored in the arithmetic processing unit, and an abnormal state such as when the teeth of the partial gears are damaged can be detected. Good.

  According to the present invention, in a gas circuit breaker using a spring as a drive source, the gear of the large gear meshing with the small gear can be attached to and detached from the large gear body at the moment when the charging of the closing spring is completed, and the mechanical strength is large. Since the teeth of another piece lower than the main body are used, the closing control mechanism can be protected. As a result, the reliability of the gas circuit breaker is improved. Further, it is not necessary to adjust the protection mechanism of the closing control mechanism, and replacement is easy.

  Embodiments of the present invention will be described below with reference to FIGS.

  FIG. 9 is a front view of the gas circuit breaker 100.

In FIG. 9, in the gas circuit breaker 100, a cylindrical grounding container 103 is installed on a gantry 105. An insulating gas, for example, SF ₆ gas (sulfur hexafluoride gas) is sealed in the ground container 103 at a specified pressure. Bushings 101 and 102 protrude obliquely upward from the axial middle portion of the ground container 103. In the bushings 101 and 102, the conductor which connects the electric wire in a substation or a switchyard, and comprises an electric circuit is accommodated. An operation box 104 that houses the spring operation mechanism of the gas circuit breaker 100 is attached to the side of the gantry 105.

  A contact having a fixed contact 62 and a movable contact 63 is disposed in the ground container 103. The state of FIG. 9 is a state in which the contact is inserted, and the movable contact 63 is in contact with the fixed contact 62. During the blocking operation, the movable contact 63 is separated from the fixed contact 62. The movable contact 63 is connected to the insulating material 64 at the end opposite to the contact end with the fixed contact 62. A rotating shaft 66 is rotatably supported by the ground container 103. One end of a link 65 and a link 67 is fixed to the rotating shaft 66. The other end of the link 65 is connected to one end of the insulating material 64. Similarly, the other end of the link 67 is connected to the link 68.

  A main shaft 4 of a spring operation mechanism is disposed in the operation box 104. The main shaft is rotatably supported by the rotary box 104. A spring operation mechanism is arranged around the main shaft 4. One end of a link 69 is fixed to the main shaft 4. The other end of the link 69 is connected to the link 68. The main shaft 4, the link 69, the link 68, the link 67, and the rotating shaft 66 form a four-bar linkage mechanism. The four-bar linkage mechanism connects the spring operation mechanism and the blocking portion.

  The operation of the gas circuit breaker 100 configured as described above will be described below. When energized, electric power is supplied to the upstream bushing 102 from a system (not shown). The electric power is guided from the bushing 102 to the contact in the ground container 103, and is supplied to the system again through the bushing 101 on the downstream side.

  When an accident occurs in the system due to lightning or the like, the operation unit in the operation box 104 is driven, the main shaft 4 and the link 69 are rotated counterclockwise, and the link 68 is moved downward. When the link 68 moves, the link 67, the rotating shaft 66, and the link 65 rotate counterclockwise, and the insulating material 64 is moved to the left. The stationary contact 62 moves away from the movable contact 63 and the contact opens. Since the contact is opened, the supply of power to the downstream side is interrupted.

In the present embodiment, the ground container 103 extends in the horizontal direction, but may extend in the vertical direction. Although a single gas circuit breaker in which a bushing is directly attached to the ground container 103 will be described, it may be incorporated in a gas insulated switchgear. Although a gas circuit breaker using SF ₆ gas will be described as an example, other switchgear such as a vacuum circuit breaker may be used.

  FIGS. 1 to 3 are schematic views showing a spring operation mechanism 400 accommodated in the operation box 104 shown in FIG. As the state changes from FIG. 1 to FIG.

  FIG. 1 is a view showing a closing state in which the closing spring 28 and the blocking spring 26 of the spring operating mechanism 400 are compressed together.

  FIG. 2 is a diagram illustrating a state in which the blocking operation is completed.

  FIG. 3 shows a state in which the closing operation is completed and the closing spring 28 is in an open state.

  FIG. 4 is a view showing that the closing spring 28 is compressed and returned to the state of FIG. 1 after the state of FIG. 3.

  The above operation will be described in detail later.

  As shown in FIG. 1, the spring operation mechanism 400 holds the driving operation of the closing operation unit 403 having the main shaft 4 and the blocking spring 26, the closing operation unit 404 having the camshaft 2 and the closing spring 28, and the closing spring 28. A closing control mechanism 402 that opens, a blocking control mechanism 401 that holds and releases the driving force of the blocking spring 26, and a closing spring energy storage device 405 whose details are shown in FIG.

  An intermediate portion of a substantially Y-shaped main lever 5 is attached to the main shaft 4 of the shut-off operation unit 403. Rollers 6 and 7 are attached to two ends of the main lever 5 having a substantially Y shape. Further, one end of a cutoff spring link 25 is rotatably attached to the remaining end portion of the main lever 5 via a pin 25a. A flange 34 is attached to the other end of the blocking spring link 25. The flange 34 holds the cutoff spring 26 disposed on the outer periphery of the cutoff spring link 25. The blocking spring 26 is held by the housing 1 on the side opposite to the end held by the flange 34.

  The structure of the closing operation unit 404 and the closing spring energy storage device 405 will be described with reference to FIGS. A cam 3 is attached to one end of a cam shaft 2 rotatably supported in the housing 1 and a large gear 52 is attached to the other end. One end of the closing spring link 27 is rotatably attached to an intermediate portion of the large gear 52. A spring receiver 35 is attached to the other end of the closing spring link 27. The spring receiver 35 holds one end side of the closing spring 28. The closing spring 28 is disposed on the outer periphery of the closing spring link 27. The opposite side of the spring receiver 35 is held by the housing 1.

  Here, an arc-shaped partial gear 53 having the same module and the same pitch as the teeth of the large gear 52 is attached to a part of the outer peripheral portion of the large gear 52. The partial gear 53 is fitted in a groove formed in the concentric shape of the large gear 52. The inner diameter side of the partial gear 53 is concentric with the outer diameter of the large gear 52, and the side portion is trapezoidal. Therefore, the inner diameter side is longer in the circumferential direction, and is configured so as not to be pulled out by centrifugal force when fitted in the groove of the large gear. In the normal state, the teeth of the partial gear 53 are stationary with the teeth of the small gear 51 engaged.

  FIG. 4 is a detailed longitudinal sectional view of the gear operation unit.

  In FIG. 4, a driving force can be transmitted to the small gear 51 from an electric motor (not shown). When accumulating the closing spring, the small gear 51 is on the driving side and the large gear 52 is on the driven side. In the closing operation, the large gear 52 is on the driving side and the small gear 51 is on the driven side. One end of the shaft 51a to which the small gear 51 is fixed is supported by the housing 1 so as to be rotatable. A fitting portion 51b to which the manual operation handle 56 is attached is formed at the other end of the shaft 51a. The manual operation handle 56 need not always be attached to the shaft 51a, and is attached only during manual operation.

  A blocking control mechanism 401 is disposed adjacent to the blocking operation unit 403. In the shut-off control mechanism 401, an intermediate portion of the second shut-off latch 8 is rotatably attached to the shaft 8 a fixed to the housing 1. An engaging portion 8 b formed at one end of the second shut-off latch 8 engages with a roller 7 provided at one end of the substantially Y-shaped main lever 5. A roller 10 is attached to the other end of the second blocking latch 8. The 2nd interruption | blocking latch 8 is formed in the shape bent by the axis | shaft 8a part. One end of a return spring 9 for returning the second blocking latch 8 to its original position is attached between the shaft 8a and the engaging portion 8b of the second blocking latch. The other end of the return spring 9 is fixed to the housing 1.

  A blocking latch 11 is disposed so as to be engageable with a roller 10 provided at one end of the second blocking latch 8. An intermediate portion of the blocking latch 11 is rotatably attached to a shaft 11 a supported by the housing 1. The shut-off latch 11 is formed in a shape bent at the shaft 11a, and a return spring 12 for returning the shut-off latch 11 having one end fixed to the housing to the original position in the middle of the shaft 11a and the roller 13. One end is attached. A roller 13 is attached to the opposite side of the engaging portion 11 b where the blocking latch 11 engages with the roller 10. The front end of a substantially L-shaped blocking trigger 14a is in contact with the roller 13 so as to be engageable with the roller 13. The tip is formed in a curved surface.

  A substantially L-shaped corner of the cutoff trigger 14a is attached to the shaft 14c. A member 14b extending in the horizontal direction is attached to the shaft 14c, and a plunger 211 of the electromagnet 201 for breaking is disposed so as to be able to contact the member 14b. A return spring 15 is attached to an intermediate portion of the cutoff trigger 14b. One end of the return spring is fixed to the housing 1 and returns the cutoff trigger 14 to its original position.

  The making control mechanism 402 has a making latch 19. The closing latch 19 can be engaged with a roller 18 attached to the cam 3. The closing latch 19 is substantially V-shaped, and its bent portion is rotatably attached to the shaft 19a. An engagement portion 19 b that engages with the roller 18 of the cam 3 is formed at one end of the V-shape of the closing latch 19. A roller 21 is attached to the other V-shaped end of the closing latch 19.

  An insertion trigger 22 is disposed so that one end of the roller 21 can come into contact with the roller 21. The throwing trigger 22 is formed in a bent shape, and the bent portion is rotatably attached to the shaft 22a. The rotating shaft 22a is rotatably supported by the housing 1. A return spring 20 having one end fixed to the housing 1 is attached in the middle from the shaft 19 a to the roller 21 of the closing latch 19. A throwing trigger 22 b is formed at the opposite end of the throwing trigger 22 that contacts the roller 21. The plunger 212 of the making electromagnet 202 is disposed so as to be able to contact the making trigger 22b.

  In the gas circuit breaker of this embodiment configured as described above, each of the return spring 9 attached to the second cutoff latch 8, the return spring 12 attached to the cutoff latch 11, and the return spring 15 attached to the cutoff trigger 14a is shown in FIG. In the input holding state shown in FIG. In the present embodiment, these return springs 9, 12, and 15 are formed by coil springs, but may be springs such as torsion coil springs and disk springs.

  The operation of the gas circuit breaker 100 will be described below. First, an operation for shifting from the on state to the cut off state shown in FIG. 1 will be described. When the interruption command is input in the on state, the circuit breaker 100 starts the interruption operation. The blocking electromagnet 201 of the blocking control mechanism 401 is excited, and the plunger 211 of the blocking electromagnet 201 protrudes. The plunger 211 presses the trigger lever 14b. As a result, the engagement between the cutoff trigger 14 and the cutoff latch 11 is released.

  The engagement with the cutoff trigger 14a is released, and the cutoff latch 11 is free to rotate. Since the blocking latch 11 is pressed from the roller 10 of the second blocking latch 8, it rotates counterclockwise around the shaft 11a. The second blocking latch 8 whose rotation is restricted becomes free to rotate, and the pressing force from the roller 7 of the main lever 5 causes the second blocking latch 8 to rotate counterclockwise around the shaft 8a. The engagement between the roller 7 of the main lever 5 and the second blocking latch 8 is released, and the main lever 5 is freely rotatable. Since the restriction of the cutoff spring 26 in the compressed state is removed, the cutoff spring 26 is released, and the main lever 5 rotates counterclockwise. The contact breaking operation is executed. When the cutoff spring 26 is fully released, the cutoff operation is finished. The roller 6 at the end of the main lever 5 stops substantially in contact with the outer peripheral surface of the cam 3 (see FIG. 2).

  The operation of moving the contact from the interrupted state to the closing state shown in FIG. 3 will be described below. When a closing command is input to the circuit breaker 100 in the blocking state shown in FIG. 2, the closing electromagnet 202 is excited. The plunger 212 of the making electromagnet 202 protrudes downward and presses the making trigger 22b. The making trigger 22 rotates counterclockwise, and the engagement between the roller 21 of the making latch 19 and the making trigger 22 is released.

  The closing lever 19 whose rotation has been restricted becomes free to rotate, and the closing latch 19 rotates counterclockwise by the pressing force from the roller 18 of the cam 3. The engagement between the closing latch 19 and the roller 18 of the cam 3 is released. Since the restriction on the rotation of the cam 3 is eliminated, the spring force of the closing spring 28 is released. The closing spring link 27 moves downward, and the large gear 52, the cam shaft 2, and the cam 3 rotate counterclockwise.

  As the cam 3 rotates, the outer peripheral surface of the cam 3 comes into contact with the roller 6 of the main lever 5. The main lever 5 rotates clockwise. When the cam 3 rotates approximately half counterclockwise, the outer peripheral surface of the cam 3 contacts the roller 6 of the main lever 5 at the maximum radius of curvature of the cam 3. At this time, the cutoff spring link 25 connected to the main lever 5 compresses the cutoff spring 26 to substantially the original position.

  When the closing spring 28 is fully released, the contact is inserted. At the end of the closing operation, the levers 8, 11, and 14 of the cutoff control mechanism 401 are returned to their original positions by the force of the return springs 9, 12, and 15. As a result, the force of the cutoff spring 26 is maintained. FIG. 3 shows a state where the closing operation has been completed. As soon as the shut-off command is input, the shut-off operation becomes possible. That is, the drive energy of 2 interruption operations and 1 closing operation is stored before the first interruption operation, and the operation responsibility of the high-speed reclosing specified in JEC-2300, O-0.35 seconds-CO Operation is possible. Here, O is a shut-off operation, and CO is a shut-off operation that is performed after the closing operation.

  The operation of storing the closing spring after the closing operation is completed will be described below. In FIG. 3, the small gear 51 is rotated clockwise through an electric motor and a gear train (not shown). The large gear 52 that meshes with the small gear 51 rotates counterclockwise. Along with this, the closing spring link 27 swings counterclockwise, and the closing spring 28 is compressed. At the time when the closing spring 28 is stored, the partial gear 53 is positioned on a straight line connecting the axis of the small gear 51 and the axis of the large gear 52.

  When energizing the closing spring 28 is started, the reference point is that the reference position of the large gear 52 is positioned vertically downward. The rotation angle of the large gear from the line connecting this point and the center of the large gear 52 is represented by θ. That is, θ = 0 when the closing spring 28 starts to accumulate energy. When the large gear 52 rotates almost half, the electric motor is stopped by a limit switch command (not shown).

  Due to the driving force of the compressed closing spring 28, the large gear 52 attempts to rotate further counterclockwise. Since the roller 18 of the cam 3 coaxial with the large gear 52 is engaged with the closing lever 19 and the closing lever 19 is engaged with the closing trigger 22, the rotation of the cam 3 and the large gear 52 is prevented, and the closing spring 28 Spring force is maintained. As a result, as shown in FIG. 1, the contact is brought into the closing holding state, and the shut-off spring 26 and the closing spring 28 are returned to the compressed initial state.

  The load F that acts on the tooth surfaces of the large gear 52 and the small gear 51 when the closing spring 28 is stored in normal operation will be described with reference to FIG.

  The horizontal axis in FIG. 8 is the rotation angle θ of the large gear. The large gear 52 and the closing spring link 27 constitute a slider / crank mechanism. The maximum load Fmax is reached when the angle θ is about 90 °. When the angle θ exceeds 90 °, the load F on the tooth surface decreases. The specifications of the large gear 52 and the small gear 51 are determined from the load Fmax acting on the tooth surface when the angle θ is about 90 °. On the other hand, in the vicinity of the angle θ = 180 ° at which the charging of the closing spring 28 is completed, the load F on the tooth surface is small. Therefore, the specifications of the closing latch 19 are designed based only on the driving force of the closing spring 28.

  On the other hand, in an abnormal state where the electric motor and the small gear 51 continue to rotate even after the closing spring 28 is stored, the load F of the large gear 52 of the conventional storage device is large near the rotation angle θ = 180 °. Become. Even if the stress of the large gear 52 is far below the limit strength at which the large gear 52 is damaged, the load F on the tooth surface acts on the closing lever 19 via the roller 18 of the cam 3 and the excessive load is applied to the closing lever 19. Works. As a result, the input control mechanism 402 may be damaged. In order to avoid damage, it is necessary to significantly increase the component strength of the input control mechanism 40, and the input control mechanism becomes larger.

  In order to eliminate such problems, in this embodiment, the meshing strength of the teeth of the large gear is partially reduced. When an abnormal state occurs, the three teeth 53e to 53g of the partial gear 53 whose strength has been reduced are damaged, the meshing with the small gear 51 is cut off, and the closing control mechanism 40 is protected. Specifically, the partial gear 53 is made of one of a low elastic modulus metal, non-metal, and resin, which has a mechanical strength lower than that of the large gear 52.

  The position of the partial gear 53 to be fitted to the large gear 52 is determined at a position where there is little influence on other parts at the time of breakage. Specifically, the position shown in FIG. In this state, the leftmost tooth 53 d of the partial gear 53 does not mesh with the small gear 51 when the charging of the closing spring 28 is completed. According to this embodiment, even if the teeth 53e to 53g are damaged in an abnormal state, only the teeth 53d at the end of the partial gear 53 are not damaged. Even if the teeth of the partial gear 53 are damaged, the meshing between the small gear 51 and the partial gear 53 is restored at the initial stage of the next closing operation, and the closing operation becomes possible. In particular, even if the teeth of the partial gear 53 are incompletely damaged, the rotation of the large gear 52 by the driving force of the closing spring 28 in the initial stage of the closing operation causes the damage of the teeth of the partial gear 53 having a low mechanical strength. The gear 51 and the large gear 52 can mesh smoothly. Further, it is possible to re-accumulate the closing spring after the closing operation is completed.

  Therefore, the circuit breaker can operate even when the teeth of the partial gear 53 are damaged. However, there is a risk that a broken piece is bitten by another mechanism part and a malfunction occurs. Therefore, when the teeth of the partial gear are damaged, the partial gear 53 can be removed from the large gear 52 and replaced in the state of the closing operation shown in FIG. Therefore, the circuit breaker can be restored in a short time.

  Another embodiment of the circuit breaker according to the present invention will be described with reference to FIGS.

  FIG. 5 is a perspective view of the large gear 52 and the partial gear 53 provided in the closing spring energy storage device.

  FIG. 6 is a perspective view of only the partial gear 53. FIG. 7 is a perspective view of only the large gear 52.

  In this embodiment, the tooth width b1 of the large gear 52 is made larger than the tooth width b2 of the partial gear 53 (b2 <b1). A slit 53 h extending in the width direction is formed at the tooth base of the partial gear 53. The portion of the partial gear 53 that fits into the large gear 52 has the same width as that of the large gear 52, but a fastening hole 53 a is formed in a portion of the partial gear 53 where no teeth are formed. The partial gear 53 is fastened and fixed to the large gear 52 via the small screw 55. The large gear 52 has a groove 52b and a screw hole 52a for fastening.

  Since the detachable partial gear 53 is fitted to the large gear, the partial gear 53 having lower mechanical strength than the large gear 52 can be used. As a result, even if an abnormal situation occurs during the closing spring accumulating operation, the teeth of the partial gear 53 are damaged first, so that the closing control mechanism can be protected.

  Further, since the slit 53h is formed at the tooth base, if an abnormal state occurs, the teeth 53e to 53g having the slit are broken prior to the other teeth, so that the small gear 51 is not reliably engaged. Since the partial gear 53 is fastened to the large gear 52 using the small screw 55, the replacement is easy even if the partial gear 53 is damaged. The material of the partial gear 53 may be the same as that of the large gear 52 or may be inferior in strength to the large gear. In the above embodiment, the tooth surface is made stronger than the other teeth without forming a slit at the root of the tooth at the end of meshing of the partial gear. Even if the length is increased and no slit is formed in the other teeth, the same effect can be obtained.

  Furthermore, another embodiment of the circuit breaker according to the present invention will be described with reference to FIGS.

  FIG. 10 is a diagram showing an abnormality detection configuration of the partial gear 53.

  FIG. 11 is a motor command and a photoelectric sensor output diagram in a standard state where the teeth of the partial gear 53 are not damaged.

  FIG. 12 is an output diagram in an abnormal state where one tooth of the partial gear 53 is damaged.

  FIG. 10 shows one state during closing spring accumulation. The photoelectric sensor 58 is fixed to the housing 1, and its detection surface faces the side surfaces of the teeth of the large gear 52 and the partial gear. The photoelectric sensor 58 is connected to an arithmetic processing unit 59, and the arithmetic processing unit 59 and the display means 60 are connected.

  In the case of the standard state of FIG. 11, when the electric motor is activated, the photoelectric sensor 58 is also activated, and the output diagrams of 61-1 and 62-1 are accumulated in the arithmetic processing unit 59, respectively. The photoelectric sensor is turned on when the teeth of the large gear 52 and the partial gear 53 are detected, and is turned off when the projected light comes between the teeth and the reflected light does not return to the detection surface.

  On the other hand, in FIG. 10, when the tooth 57 of the partial gear 53 is broken, the projected light of the photoelectric sensor passes above the broken tooth 57 as indicated by 63-2 in FIG. The state becomes longer. Therefore, the tooth breakage of the partial gear 53 can be detected by comparison with the output diagram accumulated in the arithmetic processing unit 59. Further, the breaker of the tooth of the partial gear 53 is displayed on the display means 60, so that the maintenance person in charge of the circuit breaker can replace the partial gear 53 at an early stage. Thus, according to the present embodiment, it is possible to detect the breakage of the teeth of the partial gear 53 early and accurately by the photoelectric sensor, and it is possible to improve the reliability of the circuit breaker.

The schematic diagram of one Example of the gas circuit breaker for electric power which concerns on this invention. It is a figure explaining operation of the gas breaker for electric power shown in FIG. It is a figure explaining operation of the gas breaker for electric power shown in FIG. It is front sectional drawing of the spring energy storage apparatus which the gas breaker for electric power shown in FIG. 1 has. It is a perspective view of the other Example of the large gearwheel used for the gas breaker for electric power shown in FIG. It is a perspective view of the partial gear attached to the large gear shown in FIG. FIG. 6 is a perspective view showing a state where a partial gear is removed from the large gear shown in FIG. 5. It is a figure explaining the load of a large gearwheel. It is a front view of one Example of the gas circuit breaker for electric power which concerns on this invention. It is a schematic diagram of one Example of the gas circuit breaker for electric power which concerns on this invention. It is an output diagram of a photoelectric sensor when there is no breakage of teeth of a partial gear. It is an output diagram of a photoelectric sensor when there is a breakage of teeth of a partial gear.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Housing, 2 ... Cam shaft, 3 ... Cam, 5 ... Main lever, 26 ... Shut-off spring, 28 ... Closing spring, 51 ... Small gear, 52 ... Large gear, 53 ... Partial gear, 58 ... Photoelectric sensor, 59 DESCRIPTION OF SYMBOLS ... Arithmetic processing device, 60 ... Display means, 400 ... Spring operation mechanism, 401 ... Blocking control mechanism, 402 ... Closing control mechanism, 403 ... Blocking operation unit, 404 ... Closing operation unit, 405 ... Closing spring energy storage device

Claims (15)

  In a power gas circuit breaker that switches between cutting off and turning on power by opening and closing a contact having a fixed contact and a movable contact by a storing power of a breaking spring and a closing spring, a storing means for storing the closing spring is provided. The energy storing means has a small gear, a large gear and a partial gear meshing with the small gear, and the large gear is formed in a shape in which a part of the circumferential direction is missing, and the missing gear is formed from the large gear. A gas circuit breaker for electric power, wherein the partial gear having a low meshing strength is attached.   The power gas circuit breaker according to claim 1, wherein the teeth of the partial gear are set so that the teeth of the partial gear are broken earlier than the teeth of the large gear and the meshing with the small gear is released.   2. The power gas circuit breaker according to claim 1, wherein the partial gear is configured to be detachable from a large gear.   4. The power gas circuit breaker according to claim 3, wherein the teeth of the partial gear detachably attached to the large gear have the same module and the same pitch as the teeth of the large gear.   4. The power gas circuit breaker according to claim 3, wherein the missing portion of the large gear is a groove, and the screw is fastened after fitting the partial gear into the groove.   4. The power gas circuit breaker according to claim 3, wherein the large gear and the partial gear are made of different materials.   4. The power gas circuit breaker according to claim 3, wherein a width direction length of a portion where the teeth of the partial gear are formed is narrower than a tooth width of the large gear.   The power gas circuit breaker according to claim 3, wherein a slit extending in a width direction is formed on a tooth base surface of the partial gear.   The power gas circuit breaker according to claim 3, wherein a hole for fastening with the large gear is formed in a portion where the teeth of the partial gear are not formed.   4. The power gas circuit breaker according to claim 3, wherein in the partial gear, the tooth surface strength of the teeth on the end side is made larger than those of the other teeth.   2. A photoelectric sensor is disposed in a casing that rotatably supports the large gear, and the detection unit of the photoelectric sensor is configured to face teeth of the large gear and the partial gear. The gas circuit breaker for electric power in any one of thru | or 3.   12. The power gas circuit breaker according to claim 11, wherein a start command for the photoelectric sensor is inputted at the start of charging of the closing spring, and the command of the photoelectric sensor is disconnected after completion of closing of the closing spring.   The output waveform of the photoelectric sensor in a state where the teeth of the partial gear are not damaged is stored in an arithmetic processing unit, and an abnormal state such as a case where the teeth of the partial gear are damaged can be detected. The power gas circuit breaker according to claim 12.   The power gas circuit breaker according to claim 13, further comprising display means capable of displaying an abnormal state when the teeth of the partial gear are damaged.   In addition to the output of the photoelectric sensor, the arithmetic processing unit also has an output of a sensor that detects an opening / closing command, a displacement sensor that can calculate the stroke of the movable contactor, or a sensor that can detect the timing of opening / closing of a contact. The power gas circuit breaker according to claim 14, wherein the power gas circuit breaker is connected.

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