breaker

Abstract

The circuit breaker comprises: a ratchet gear, a conveying claw (92), an anti-reverse claw, a motor (94) and a load reduction unit (100). The ratchet gear is preloaded in a first direction by a closing spring. The motor (94) is provided with an output shaft (94a) on a transmission mechanism (95) provided between the motor (94) and the conveying claw (92), and the conveying claw (92) is moved via the transmission mechanism (95) by rotating the output shaft (94a), so that the ratchet gear rotates in a second direction, which is opposite to the first direction. The load reduction unit (100) reduces the rotation speed of the motor (94) during the period from when the ratchet gear rotated in the second direction by the conveying claw (92) is restricted from rotating in the first direction by the anti-reverse claw until the ratchet gear is rotated in the second direction by the conveying claw (92) next time.

Description

Technical Field

[0001] The invention relates to a circuit breaker which stores energy in a closing spring through a motor and sets a circuit to a closed state through the force of the energy-stored closing spring. Background Art

[0002] Conventionally, circuit breakers having a ratchet-type charging mechanism for storing energy in a closing spring by means of an electric motor are known. For example, Patent Document 1 discloses a circuit breaker having: a ratchet gear preloaded by a closing spring; a delivery pawl engaged with the ratchet gear; and a motor that rotates the ratchet gear by means of the delivery pawl to store energy in the closing spring.

[0003] In a circuit breaker having a ratchet type charging mechanism, a load period and a no-load period are generated alternately. The load period is the period from when the delivery pawl causes the ratchet gear to start rotating in the opposite direction of the preload direction of the closing spring until the anti-reverse pawl restricts the rotation of the ratchet gear in the preload direction. The no-load period is the period from when the anti-reverse pawl restricts the rotation of the ratchet gear in the preload direction until the next delivery pawl causes the ratchet gear to start rotating in the opposite direction of the preload direction.

[0004] Patent Document 1: Japanese Utility Model Application Laid-Open No. 3-127740

[0005] However, in a circuit breaker having a ratchet-type charging mechanism, when switching from a no-load period to a load period, a large load is suddenly applied to a transmission mechanism provided between the conveying claw and the motor. Summary of the invention

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to obtain a circuit breaker capable of reducing the magnitude of the load applied to the transmission mechanism when switching from a no-load period to a load period.

[0007] In order to solve the above-mentioned problems and achieve the purpose, the circuit breaker of the present invention has a ratchet gear, a conveying claw, an anti-reverse claw, a motor and a load reduction unit. The ratchet gear is preloaded in the first direction by a closing spring. The conveying claw is engaged with the ratchet gear. The anti-reverse claw limits the rotation of the ratchet gear in the first direction by the closing spring. The motor is installed with an output shaft on a transmission mechanism provided between the conveying claw and the motor, and the conveying claw is moved through the transmission mechanism by rotating the output shaft, so that the ratchet gear rotates in the opposite direction of the first direction, that is, in the second direction. The load reduction unit reduces the rotation speed of the motor during the period from when the ratchet gear rotated in the second direction by the conveying claw is restricted from rotating in the first direction due to the anti-reverse claw until the ratchet gear rotates in the second direction by the conveying claw next time.

[0008] Effects of the Invention

[0009] According to the present invention, there is an effect that the magnitude of the load applied to the transmission mechanism when switching from a no-load period to a load period can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a side cross-sectional view of the circuit breaker in the open state after charging according to the first embodiment of the present invention.

[0011] Figure 2 Yes means Figure 1 A diagram showing a state of a portion of the structure of a circuit breaker.

[0012] Figure 3 This is a diagram showing the relationship among the main shaft, the insulating link arm, and the insulating link according to the first embodiment.

[0013] Figure 4 Yes means Figure 1 A diagram showing a state of a portion of the structure of a circuit breaker.

[0014] Figure 5 It is a cross-sectional view of the circuit breaker body when the circuit breaker according to the first embodiment is in the tripped state.

[0015] Figure 6 Yes means Figure 5 A diagram showing a state of a portion of the structure of a circuit breaker.

[0016] Figure 7 It is a side view showing an example of the electric charging mechanism according to the first embodiment.

[0017] Figure 8 It is a front view showing an example of the electric charging mechanism according to the first embodiment.

[0018] Fig. 9 It is a side view showing an example of the electric charging mechanism according to the first embodiment.

[0019] Fig.10 This is a diagram for explaining the operation of the electric charging mechanism according to the first embodiment.

[0020] Fig.11 This is a diagram showing changes in load torque applied to the output shaft of the reduction gear in the electric charging mechanism according to the first embodiment.

[0021] Fig.12 This is a diagram showing an example of the structure of the cam according to the first embodiment.

[0022] Fig.131 is a diagram showing an example of the relationship between the motor and the contact portion of the micro switch in the electric charging mechanism according to the first embodiment.

[0023] Fig.14 This is a diagram showing another example of the relationship between the motor and the contact portion of the micro switch in the electric charging mechanism according to the first embodiment.

[0024] Fig.15 This is a diagram showing changes in the load torque and the contact state of each micro switch according to the first embodiment.

[0025] Description of the label

[0026] 1 circuit breaker, 4 arc extinguishing chamber, 6 electrical system, 7 mechanism system, 10 frame, 10a molded shell, 10b molded cover, 16, 16a, 16b frame, 16c long hole, 17 guide plate, 18 closing spring, 21 cam shaft, 22 charging cam, 22a cam side roller, 22b cam surface, 24 charging arm, 24a common fixed shaft, 24b arm side roller, 24c working surface, 24d spring hook pin, 25 1 closing spring key, 25a spring key side roller, 26 second closing spring key, 26a, 30a fixed shaft, 26b protrusion, 26c engaging portion, 27 closing lever, 28 main shaft, 28a insulating connecting rod arm, 28b second connecting rod arm, 29 closing toggle mechanism, 29a first connecting rod, 29b second connecting rod, 29c, 29d, 30b pin, 29e connecting rod side roller, 30 connecting rod lever, 30c lever side roller, 31 jump 1. a spring key, 2. a trip rod, 3. a insulating connecting rod, 4. a fixed conductor on the load side, 4. a movable contact, 4. a fixed conductor on the power supply side, 4. a fixed contact, 4. a flexible conductor, 4. a movable holder, 4. a crimping spring, 4. a holder shaft, 4. a connecting pin, 8. a nut, 9. a electric charging mechanism, 9. a ratchet gear, 9. a gear tooth, 9. a conveying claw, 9. a front end portion, 9. a 3 anti-reverse claw, 94 electric motor, 94a, 95c output shaft, 95 transmission mechanism, 95a reduction gear, 95b rotating component, 96, 98 springs, 100 load reduction portion, 101, 111 cam, 101a, 111a recessed portion, 101b opening portion, 102a, 112a actuator, 102b, 112b contact portion, E power supply, R1, R2 resistors, SW1, SW2 micro switches. DETAILED DESCRIPTION

[0027] Hereinafter, a circuit breaker according to an embodiment of the present invention will be described in detail based on the drawings. In addition, the present invention is not limited to this embodiment.

[0028] Implementation method 1.

[0029] Figure 1It is a side cross-sectional view of the circuit breaker in the open state after charging according to the first embodiment of the present invention. Figure 2 Yes means Figure 1 A diagram showing a state of a portion of the structure of a circuit breaker. Figure 3 This is a diagram showing the relationship among the main shaft, the insulating link arm, and the insulating link according to the first embodiment. Figure 4 Yes means Figure 1 A diagram showing a state of a portion of the structure of a circuit breaker. Figure 5 It is a cross-sectional view of the circuit breaker body when the circuit breaker according to the first embodiment is in the tripped state. Figure 6 Yes means Figure 5 A diagram showing a state of a portion of the structure of a circuit breaker.

[0030] Figure 1 The circuit breaker 1 shown is an air circuit breaker, and is connected between a power supply device (not shown) and a load device (not shown). The load device is, for example, an electrical device that consumes the power supplied from the power supply device. The circuit breaker 1 has an insulating frame 10, and the frame 10 has a molded case 10a and a molded cover 10b. In the frame 10, Figure 1 On the right side of the figure, there are components of the electrical system 6 that mainly open and close the main circuit. Figure 1 Components of the mechanism system 7 for opening and closing are arranged on the left side in FIG.

[0031] The electrical system 6 of the circuit breaker 1 includes: a load-side fixed conductor 42, one end of which protrudes from the frame 10 and is connected to the load device; a movable contact 43, which is fixedly connected to a movable contact 43a; and a power-side fixed conductor 44, one end of which protrudes from the frame 10 and is connected to the power device, and the other end of which is fixedly connected to a fixed contact 44a opposite to the movable contact 43a. Figure 1 In the multiple drawings, in order to make the description easier to understand, a three-dimensional orthogonal coordinate system is shown in which the vertical direction is set as the direction of the Z axis, the direction in which the load-side fixed conductor 42 and the power-side fixed conductor 44 extend is set as the direction of the X axis, and the direction orthogonal to the X axis and the Z axis is set as the direction of the Y axis.

[0032] In addition, the electrical system 6 has a flexible conductor 45, one end of which is fixed to the frame 10 and the other end of which is fixed to the movable contact 43. The movable contact 43a is in contact with the fixed contact 44a, whereby the load-side fixed conductor 42 and the power-side fixed conductor 44 are electrically connected via the flexible conductor 45. The movable contact 43 provided with the movable contact 43a is mounted on the mechanism system 7 via a connecting pin 49 and is driven by the mechanism system 7.

[0033] In addition, the electrical system 6 includes: a movable member holder 46, one end of which is rotatably mounted on a holder shaft 48 held by the molded housing 10a; a pressure spring 47, which is installed between the molded housing 10a and the movable contact 43; and an arc extinguishing chamber 4. Figure 1 In the open circuit state shown, the movable contact 43a is preloaded in the direction of pulling the movable contact 43a away from the fixed contact 44a by the crimping spring 47. Figure 4 In the closed state shown, the movable contact 43a is preloaded in a direction of pressing the movable contact 43a against the fixed contact 44a by the pressure spring 47. The arc extinguishing chamber 4 interrupts the arc generated when the movable contact 43a is pulled away from the fixed contact 44a.

[0034] Next, the mechanism system 7 of the circuit breaker 1 will be described. Figure 2 As shown, the circuit breaker 1 includes: a frame 16 fixed to the frame body 10, including a pair of frames 16a and 16b; a cam shaft 21; and a nut 82. The frame 16a and the frame 16b are arranged at a distance from each other by the cam shaft 21 and the nut 82. The cam shaft 21 is a bolt, but it may be a member other than a bolt.

[0035] The mechanism system 7 is disposed so as to be sandwiched between the frames 16a and 16b. The holder shaft 48, the connecting pin 49, and the axes in the mechanism system 7 are disposed so as to be parallel to the axis of the cam shaft 21, that is, in the Y-axis direction, unless otherwise specified.

[0036] The mechanism system 7 of the circuit breaker 1 comprises: a guide plate 17, one end of which is fixed to the frame 16, Figure 1 closing spring 18, which is mounted on the guide plate 17; charging arm 24, the middle portion of which is rotatably supported on a common fixed shaft 24a; and the charging cam 22, which causes the charging arm 24 to rotate.

[0037] A spring hook pin 24d is provided at one end of the charging arm 24, and the spring hook pin 24d is inserted into a long hole 16c formed in the frame 16. One end of the closing spring 18 abuts against the spring hook pin 24d, and the other end abuts against the frame 16. The charging cam 22 is fixed to the cam shaft 21.

[0038] The mechanism system 7 has an electric charging mechanism 90, which rotates the charging cam 22 to store energy in the closing spring 18. The electric charging mechanism 90 has a ratchet gear 91. The ratchet gear 91 is fixed to the camshaft 21 in the same manner as the charging cam 22, and the electric charging mechanism 90 rotates the charging cam 22 by rotating the ratchet gear 91. In addition, the specific structure of the electric charging mechanism 90 will be described in detail later.

[0039] An arm side roller 24b is provided at the other end of the charging arm 24, and the arm side roller 24b abuts against the cam surface 22b of the charging cam 22. The arm side roller 24b moves along the cam surface 22b by the rotation of the charging cam 22.

[0040] The mechanism system 7 includes a first closing latch 25 whose base end is rotatably supported on the common fixed shaft 24a, a second closing latch 26 rotatably supported on the fixed shaft 26a, and a closing lever 27 a part of which is formed in a semi-cylindrical shape.

[0041] The charging cam 22 has a cam side roller 22a provided between the charging cam 22 and the ratchet gear 91, and the front end of the first closing latch 25 abuts against the cam side roller 22a. A latch side roller 25a is provided in the middle between the base end and the front end of the first closing latch 25, and the latch side roller 25a abuts against one end of the second closing latch 26.

[0042] A protrusion 26b and an engaging portion 26c are formed at one end of the second closing latch 26. The second closing latch 26 is supported by a return spring (not shown). Figure 1 The counterclockwise force in the circuit breaker 1 causes the protrusion 26b to rotate the first closing latch 25 clockwise. Figure 1 In the state shown, the first closing latch 25 is in contact with the cam side roller 22a, and the cam side roller 22a serves as a stopper to hold the first closing latch 25 in a non-rotatable state. In addition, the closing lever 27 rotates clockwise by manual operation of an on button (not shown) or an on operation of a solenoid or the like.

[0043] like Figure 3 As shown, the mechanism system 7 includes: a main shaft 28; an insulating link arm 28a, which is fixed to the main shaft 28; and a second link arm 28b, which is fixed to the main shaft 28 and arranged between the insulating link arms 28a. The main shaft 28 is rotatably supported by the frame 16. Three insulating link arms 28a are arranged at equal intervals at the base end of the main shaft 28 along the extension direction. The insulating link arm 28a and the second link arm 28b have the same shape. The insulating link arm 28a is rotatably connected to the frame 16 by a pin (not shown). Figure 4 One end of the insulating link 41 is shown. The other end of the insulating link 41 is connected to the movable contact 43.

[0044] like Figure 1 and Figure 4 As shown, the mechanism system 7 comprises: a closing toggle mechanism 29; a connecting rod lever 30 rotatably supported on a fixed shaft 30a; a trip spring key 31 rotatably supported on a fixed shaft 26a; and a trip rod 32 engaged with one end of the trip spring key 31.

[0045] The closing toggle mechanism 29 includes a first connecting rod 29a, a second connecting rod 29b, pins 29c and 29d. One end of the first connecting rod 29a is rotatably connected to one end of the connecting rod lever 30 through a pin 30b. The other end of the first connecting rod 29a and one end of the second connecting rod 29b are connected through a pin 29d. The other end of the second connecting rod 29b is connected to the other end of the second connecting rod arm 28b through a pin 29c. A lever side roller 30c is provided in the middle portion between one end and the rotation center of the connecting rod lever 30. The side surface of the tripping latch 31 is engaged with the lever side roller 30c.

[0046] exist Figure 1 In the state shown in FIG. 1 , if the on button (not shown) is pressed, the closing lever 27 rotates clockwise, and the lock of the second closing latch 26 by the closing lever 27 is released. The unlocked second closing latch 26 is in Figure 1 The cam 22 rotates clockwise in the middle of the first closing latch 25, and the engagement between the engaging portion 26c and the latch side roller 25a is disengaged. Figure 1 Rotate counterclockwise while Figure 1 Since the arm side roller 24b rotates counterclockwise in the charging cam 22, the arm side roller 24b falls into the step portion of the cam surface 22b of the charging cam 22. Therefore, the charging arm 24 becomes a free state.

[0047] If the charging arm 24 becomes free, the release force of the closing spring 18 causes the charging arm 24 to be released. Figure 1 The working surface 24c passes over the connecting rod side roller 29e of the closing toggle mechanism 29. The tripping spring 31 is rotated counterclockwise by the tripping rod 32. Figure 1 The counterclockwise movement in the circuit is locked, so the closing toggle mechanism 29 extends, causing the second connecting rod arm 28b to move in the direction of the Figure 1 Rotate counterclockwise.

[0048] Therefore, if Figure 5 and Figure 6 As shown, in the circuit breaker 1, the movable contact 43a and the fixed contact 44a are in contact, and the circuit is closed. Figure 5 In the state shown, the connecting rod lever 30 is given a pressure by the pressing spring 47 via the closing toggle mechanism 29 and the pin 30b. Figure 5 The clockwise rotation force in the trip rod 32 prevents the connecting rod lever 30 from rotating. Figure 5 Counterclockwise rotation in.

[0049] like Figure 5 As shown in the tripping state where the closing spring 18 is released, if the ratchet gear 91 in the electric charging mechanism 90 is driven, the ratchet gear 91 is Figure 5 The charging cam 22 rotates counterclockwise in Figure 5Thus, the charging arm 24 rotates counterclockwise around the camshaft 21. Figure 5 Rotate clockwise to Figure 1 In the position shown, the spring hook pin 24d presses the closing spring 18 down, so that the closing spring 18 is charged. Figure 1 and Figure 4 The energy storage completion status is shown.

[0050] Next, the structure of the electric charging mechanism 90 will be described in detail. Figure 7 It is a side view showing an example of the electric charging mechanism according to the first embodiment. Figure 8 It is a front view showing an example of the electric charging mechanism according to the first embodiment. Fig. 9 1 is a side view showing an example of the electric charging mechanism involved in the first embodiment. Figure 8 and Fig. 9 In the figure, a part of the structure of the electric charging mechanism 90 including the ratchet gear 91 is not shown.

[0051] like Figure 7 As shown, the electric charging mechanism 90 has: a ratchet gear 91, which is formed with a plurality of gear teeth 91a; a conveying claw 92; an anti-reverse claw 93; and springs 96 and 98. The ratchet gear 91 is connected to the charging arm 24, the charging cam 22 and the cam shaft 21 through the closing spring 18. Figure 7 Hereinafter, the direction in which the ratchet gear 91 rotates due to the pretensioning by the closing spring 18 may be described as a pretensioning direction. The pretensioning direction is an example of a first direction.

[0052] The front end 92a of the conveying claw 92 is engaged with the gear teeth 91a of the ratchet gear 91. The spring 96 is provided between the base end of the conveying claw 92 and the frame 16 to hold the conveying claw 92 in place. Figure 7 Preload counterclockwise.

[0053] The base end of the anti-reverse claw 93 is rotatably mounted on the frame 16. The anti-reverse claw 93 is rotatably mounted on the frame 16 by a spring 98. Figure 7 The front end 93a is engaged with the gear teeth 91a of the ratchet gear 91. Thus, the anti-reverse pawl 93 restricts the rotation of the ratchet gear 91 in the pre-tensioning direction. In addition, the anti-reverse pawl 93 does not restrict the rotation of the ratchet gear 91 in the opposite direction to the pre-tensioning direction.

[0054] Electric charging mechanism 90 Figure 8As shown, there are a motor 94 and a transmission mechanism 95 that transmits the rotational force of the output shaft 94a of the motor 94 to the conveying claw 92. The motor 94 is a DC motor that rotates the output shaft 94a by DC power, but may also be an AC motor.

[0055] The transmission mechanism 95 includes a reduction gear 95a, the gear on the input side of which is mounted on the output shaft 94a of the motor 94, and a rotating member 95b, which is mounted on the output shaft 95c of the reduction gear 95a and rotates around the output shaft 95c. The base end of the conveying claw 92 is rotatably mounted at a position offset from the rotation center of the rotating member 95b.

[0056] The rotating member 95b passes through Figure 7 The spring 96 shown in FIG. 1 is rotated with the output shaft 95c as the center. Figure 7 If the output shaft 94a of the motor 94 rotates and the output shaft 95c of the reduction gear 95a rotates, the rotating member 95b rotates in the counterclockwise direction. Figure 7 If the rotating member 95b rotates counterclockwise in Figure 7 The conveying claw 92 rotates counterclockwise in the middle, and the conveying claw 92 repeats the same reciprocating curved motion as the arc slider crank a plurality of times, thereby rotating the ratchet gear 91.

[0057] As described above, in the electric charging mechanism 90, the transmission mechanism 95 provided between the motor 94 and the conveying claw 92 is provided with an output shaft 94a, and the conveying claw 92 is reciprocated by the rotation of the output shaft 94a via the transmission mechanism 95. As a result, the ratchet gear 91 rotates in the opposite direction to the pre-tightening direction. The opposite direction to the pre-tightening direction is an example of the second direction.

[0058] Fig.10 FIG. 9 is a diagram for explaining the operation of the electric charging mechanism according to the first embodiment. Fig.10 In the first state shown, the conveying claw 92 is engaged with the gear teeth 91a of the ratchet gear 91. The electric charging mechanism 90 rotates the output shaft 94a of the motor 94 from the first state, thereby the conveying claw 92 moves to make the gear teeth 91a in Fig.10 The ratchet gear 91 moves in a counterclockwise direction. Fig.10 Rotate counterclockwise to become Fig.10 In the second state, the load from the ratchet gear 91 is applied to the transmission mechanism 95 via the conveying claw 92 by the biasing force of the closing spring 18 on the ratchet gear 91 .

[0059] The electric charging mechanism 90 further rotates the output shaft 94a of the motor 94 from the second state, so that the conveying claw 92 moves to make the gear teeth 91a Fig.10The ratchet gear 91 moves in a counterclockwise direction. Fig.10 Rotate counterclockwise to become Fig.10 The third state shown. In the third state, the electric charging mechanism 90 is at a dead point position where the load from the ratchet gear 91 applied to the transmission mechanism 95 via the conveying claw 92 becomes zero.

[0060] The electric charging mechanism 90 further rotates the output shaft 94a of the motor 94 from the third state, so that the conveying claw 92 moves to make the gear teeth 91a Fig.10 The ratchet gear 91 is moved in the opposite direction of the counterclockwise rotation direction. Fig.10 The ratchet gear 91 is preloaded clockwise in the middle, so that the ratchet gear 91 is in a state where the preload force is applied by the closing spring 18. Fig.10 Rotate clockwise to become Fig.10 The 4th state is shown.

[0061] If the electric charging mechanism 90 further rotates the output shaft 94a of the motor 94 from the fourth state, the ratchet gear 91 Fig.10 The anti-reverse pawl 93 is engaged with the gear teeth 91a of the ratchet gear 91 by rotating clockwise in the middle. The anti-reverse pawl 93 is engaged with the gear teeth 91a of the ratchet gear 91, thereby Fig.10 After the anti-reverse claw 93 is engaged with the gear teeth 91a of the ratchet gear 91, if the output shaft 94a of the motor 94 rotates further, the clockwise rotation of the motor 94 stops. Fig.10 In the fifth state, the friction force generated between the conveying claw 92 and the ratchet gear 91 is applied to the conveying claw 92, but the ratchet gear 91 does not rotate due to the anti-reverse claw 93, so the preload generated by the closing spring 18 is not applied to the transmission mechanism 95 via the conveying claw 92.

[0062] Fig.11 This is a diagram showing changes in load torque applied to the output shaft of the reduction gear in the electric charging mechanism according to the first embodiment. Fig.11 The 1st to 5th states in Fig.10 The 1st to 5th states shown in FIG. Fig.11 In FIG. 1 , the vertical axis represents the load torque applied to the output shaft 95c of the reduction gear 95a, and the horizontal axis represents the rotation angle of the output shaft 95c of the reduction gear 95a.

[0063] The output shaft 95c of the reduction gear 95a rotates the ratchet gear 91 at an angle corresponding to the gear teeth 91a in each cycle from time t10 to t30 when the output shaft 95c of the reduction gear 95a rotates once. Figure 1In addition, time t30 is the time before switching from the no-load period to the load period.

[0064] Fig.11 The load period shown is the period from time t10 to time t20. That is, the load period is the period from when the ratchet gear 91 starts to rotate in the opposite direction of the preload direction due to the conveying claw 92, until the rotation in the preload direction is restricted by the anti-reverse claw 93, during the period when the output shaft 95c of the reduction gear 95a rotates one circle. During this load period, the load from the ratchet gear 91 is applied to the transmission mechanism 95 by the preload force generated by the closing spring 18.

[0065] in addition, Fig.11 The no-load period shown is the period from time t20 to time t30. That is, the no-load period is the period from the time when the rotation of the ratchet gear 91 in the preload direction is restricted by the anti-reverse claw 93 until the ratchet gear 91 is rotated in the opposite direction of the preload direction by the conveying claw 92 next time in one cycle. In other words, the no-load period is the period when the torque generated by the preload force of the closing spring 18 is not applied to the transmission mechanism 95.

[0066] As described above, in the electric charging mechanism 90, the load period and the no-load period are repeated by the rotation of the output shaft 95c of the reduction gear 95a. When switching from the no-load period to the load period, the conveying claw 92 is pressed against the gear teeth 91a of the stopped ratchet gear 91. Therefore, the higher the moving speed of the conveying claw 92, the greater the load will be suddenly applied to the transmission mechanism 95. Therefore, the electric charging mechanism 90 of the circuit breaker 1 has a load reduction unit 100 that reduces the rotation speed of the motor 94 during the no-load period. The rotation speed of the motor 94 is the rotation speed of the output shaft 94a in the motor 94.

[0067] The load reduction unit 100 is as follows Figure 8 As shown, there are: a cam 101, which is mounted on the output shaft 95c of the reduction gear 95a; and a micro switch SW1, which is set at a position opposite to the cam 101. The cam 101 rotates synchronously with the rotation of the output shaft 95c of the reduction gear 95a. In addition, Figure 8 In the illustrated example, the cam 101 is attached to the output shaft 95c, but may be attached to another rotating shaft that rotates synchronously with the output shaft 95c.

[0068] Fig.12 FIG. 1 is a diagram showing an example of the structure of the cam involved in Embodiment 1. Fig.12As shown, the cam 101 is formed in a disk shape, and a recess 101a is formed in a part of the outer edge. In addition, the cam 101 is provided with an opening 101b in the center for inserting the output shaft 95c of the reduction gear 95a.

[0069] Micro switch SW1 Fig. 9 As shown, the micro switch SW1 includes an actuator 102a that contacts the outer edge of the cam 101 and a contact portion 102b that is connected to a circuit that supplies power to the motor 94 and controls the motor 94 based on the position of the actuator 102a. The micro switch SW1 is, for example, a c-contact switch.

[0070] The actuator 102a of the micro switch SW1 abuts against the recessed portion 101a of the cam 101 during at least a portion of the no-load period. Fig.11 In the range from time t21 to the position immediately before time t30, the actuator 102a contacts the recessed portion 101a of the cam 101. At time t30, the actuator 102a is not in contact with the recessed portion 101a. Fig.11 During the period from time t21 to time t30 shown, the contact point b of the micro switch SW1 is turned on, and then at time t30 immediately before switching from the no-load period to the load period, the contact point a of the micro switch SW1 is turned on.

[0071] Fig.13 FIG. 1 is a diagram showing an example of the relationship between the motor and the contact portion of the micro switch in the electric charging mechanism according to the first embodiment. Fig.13 In the example shown, the contact portion 102b of the micro switch SW1 is connected in series with the motor 94, and the motor 94 is connected to the series connection of the resistor R1, the power source E, and the contact portion 112b of the micro switch SW2 or the resistor R2. The structure of the micro switch SW2 will be described later.

[0072] The contact portion 102b connects the motor 94 to the series connection of the resistor R1, the power source E, and the contact portion 112b of the micro switch SW2 at a position where the actuator 102a does not abut against the recess 101a. Thus, the current flows from the power source E to the motor 94 via the resistor R1 and the contact portion 112b. In addition, the contact portion 102b connects the motor 94 to the resistor R2 at a position where the actuator 102a abuts against the recess 101a. Thus, the power supply to the motor 94 is cut off during at least a portion of the no-load period.

[0073] Furthermore, the resistor R2 is connected in parallel with the motor 94, so that the current flows through the resistor R2 due to the induced electromotive force of the motor 94, and the motor 94 is braked. Therefore, the rotation speed of the motor 94 is reduced. The magnitude of the brake applied to the motor 94 is determined by the resistance value of the resistor R2.

[0074] As described above, the electric charging mechanism 90 reduces the rotation speed of the motor 94 during at least a portion of the no-load period. Therefore, when switching from the no-load period to the loaded period, the rotation speed of the motor 94 is reduced compared to the case where the electric motor 94 continues to be supplied with power. Therefore, the kinetic energy when switching from the no-load period to the loaded period can be reduced, and the load applied to the transmission mechanism 95 can be reduced when switching from the no-load period to the loaded period. In addition, when the electric motor 94 continues to be supplied with power, if the no-load period is long, the rotation speed of the motor 94 becomes high during the no-load period. Therefore, when the electric motor 94 continues to be supplied with power, if the no-load period is long, the load applied to the transmission mechanism 95 when switching from the no-load period to the loaded period becomes further increased. In the electric charging mechanism 90, the rotation speed of the motor 94 is reduced during at least a portion of the no-load period, so even when the no-load period is long, the load applied to the transmission mechanism 95 can be reduced.

[0075] Fig.14 FIG. 2 is a diagram showing another example of the relationship between the motor and the contact portion of the micro switch in the electric charging mechanism according to the first embodiment. Fig.14 In the example shown, the micro switch SW1 is connected in series to the motor 94, the contact portion 112b of the micro switch SW2, and the power source E, and either the resistor R1 or the resistor R2 is connected in series to the motor 94. The resistance value of the resistor R1 is smaller than the resistance value of the resistor R2.

[0076] The contact portion 102b connects the motor 94 to the resistor R1 at a position where the actuator 102a does not abut against the recess 101a. Thus, the current flows from the power source E to the motor 94 via the resistor R1. In addition, the contact portion 102b connects the motor 94 to the resistor R2 at a position where the actuator 102a abuts against the recess 101a. Thus, the current flows from the power source E to the motor 94 via the resistor R2, and therefore, compared with the case where the motor 94 is connected to the power source E via the resistor R1, the power supplied to the motor 94 becomes smaller, and the rotation speed of the motor 94 is reduced.

[0077] As described above, the electric charging mechanism 90 reduces the rotation speed of the motor 94 during at least a portion of the no-load period. Fig.14 The circuit shown is also Fig.13Similarly, the circuit shown can reduce the kinetic energy when switching from the no-load period to the loaded period, and can reduce the magnitude of the load applied to the transmission mechanism 95 when switching from the no-load period to the loaded period.

[0078] In addition, in the above example, the electric charging mechanism 90 is Fig.11 The rotation speed of the motor 94 is reduced during the period from the time t21 to the time immediately before the time t30 shown in the figure, but this is not limited to this example. That is, as long as the kinetic energy when switching from the no-load period to the loaded period can be reduced, the period for reducing the rotation speed of the motor 94 is not limited to the period from the time t21 to the time immediately before the time t30.

[0079] In addition, in the above-mentioned example, the concave portion 101a is formed on the outer edge of the cam 101, but a convex portion may be provided on the outer edge of the cam 101 instead of the concave portion 101a. In this case, the actuator 102a abuts against the convex portion of the cam 101 during at least a portion of the no-load period. Thus, the rotation speed of the motor 94 can be reduced during the no-load period. In addition, the cam 101 may also be configured to provide grooves of different depths in the circumferential direction instead of providing a concave portion or a convex portion on the outer edge. In this case, the actuator 102a of the micro switch SW1 abuts against the groove of the cam 101.

[0080] In the above example, the micro switch SW1 and the cam 101 are used to reduce the rotation speed of the motor 94 during the no-load period, but an optical position sensor and the micro switch SW1 may also be included. Fig.11 In the fifth state shown, the contact a of the micro switch SW1 is opened at the position immediately before the first state, and then the contact a of the micro switch SW1 is turned on when the position becomes the first state.

[0081] Next, the function of the micro switch SW2 is described. Fig. 9 As shown, the electric charging mechanism 90 includes: a cam 111, which is mounted on the camshaft 21; and a micro switch SW2, which is arranged at a position opposite to the cam 111. The cam 111 is formed in a disc shape similar to the cam 101, and a recess 111a is formed in a part of the outer edge. In addition, the cam 111 is provided with an opening (not shown) in the center for the camshaft 21 to be inserted through.

[0082] Micro switch SW2 Fig. 9As shown, the micro switch SW2 has an actuator 112a that abuts against the outer edge of the cam 111, and a contact portion 112b that controls the motor 94 based on the position of the actuator 112a. The micro switch SW2 is a b-contact switch. The contact portion 112b connects the motor 94 to the power source E at a position where the actuator 112a does not abut against the recess 111a. In addition, the contact portion 112b disconnects the motor 94 from the power source E at a position where the actuator 112a abuts against the recess 111a.

[0083] Fig.15 This is a diagram showing changes in the load torque and the contact state of each micro switch according to the first embodiment. Fig.15 The micro switch SW1 shown is the circuit breaker 1 in Figure 5 The state shown is the on state. When the circuit breaker 1 becomes Figure 1 In the case of the state shown in FIG. 1 , the circuit breaker 1 becomes disconnected. Figure 1 In the state shown, the power supply to the motor 94 is cut off.

[0084] In addition, the micro switch SW1 is turned off until the circuit breaker 1 is turned off. Figure 5 The status shown becomes Figure 1 The state shown in the figure is repeatedly turned on and off. Fig.13 In the case of the connection relationship shown, the contact a of the micro switch SW1 is a contact for connecting the motor 94 to the power source E, and the contact b of the micro switch SW1 is a contact for disconnecting the motor 94 from the power source E.

[0085] As described above, the circuit breaker 1 according to the first embodiment includes: the ratchet gear 91 which is biased in the first direction by the closing spring 18; the feeding claw 92 which is engaged with the ratchet gear 91; and the anti-reverse claw 93 which restricts the rotation of the ratchet gear 91 in the first direction caused by the closing spring 18. In addition, the circuit breaker 1 includes a motor 94 and a load reduction unit 100. The motor 94 includes the load reduction unit 100. The motor 94 is provided with an output shaft 94a mounted on a transmission mechanism 95 provided between the motor 94 and the feeding claw 92, and the feeding claw 92 is moved via the transmission mechanism 95 by rotating the output shaft 94a, so that the ratchet gear 91 is rotated in the second direction which is the opposite direction to the first direction. The load reduction unit 100 reduces the rotation speed of the motor 94 during the no-load period, which is the period from when the anti-reverse claw 93 restricts the rotation of the ratchet gear 91 in the first direction, which has been rotated in the second direction by the conveying claw 92, until the ratchet gear 91 is next rotated in the second direction by the conveying claw 92. Thus, the circuit breaker 1 can reduce the size of the load applied to the transmission mechanism 95 when switching from the no-load period to the loaded period.

[0086] In addition, the load reduction unit 100 has a cam 101 and a micro switch SW1. The micro switch SW1 is an example of a switch. The cam 101 rotates synchronously with the rotation of the output shaft 95c of the transmission mechanism 95. The micro switch SW1 has: an actuator 102a, which abuts against the cam 101; and a contact portion 102b, which controls the motor 94 based on the position of the actuator 102a. As a result, the size of the load applied to the transmission mechanism 95 can be reduced when switching from a no-load period to a load period through a relatively simple structure.

[0087] In addition, a concave portion 101a or a convex portion is formed on the outer edge of the cam 101. The actuator 102a abuts against the concave portion 101a or the convex portion during the no-load period. The contact portion 102b is connected to a circuit that supplies power to the motor 94. When the actuator 102a moves to a position abutting against the concave portion 101a or the convex portion, the power supplied to the motor 94 is reduced or the power supplied to the motor 94 is made zero, thereby reducing the rotation speed of the motor 94. As a result, the size of the load applied to the transmission mechanism 95 can be reduced when switching from the no-load period to the load period through a relatively simple structure.

[0088] The structure shown in the above embodiment is an example of the content of the present invention, and it is also possible to combine with other well-known technologies. Without departing from the scope of the present invention, part of the structure can be omitted or changed.

Claims

1. A circuit breaker, characterized in that: have: A ratchet gear which is preloaded in a first direction by a closing spring; a conveying claw engaged with the ratchet gear; an anti-reverse pawl which limits the rotation of the ratchet gear in the first direction by the closing spring; a motor having an output shaft mounted on a transmission mechanism provided between the motor and the conveying claw, wherein the output shaft is rotated to move the conveying claw via the transmission mechanism, thereby rotating the ratchet gear in a second direction opposite to the first direction; as well as Load reduction unit, The load reduction unit has: a cam that rotates in synchronization with the rotation of the output shaft of the transmission mechanism; and a switch including an actuator that abuts against the cam and a contact portion that controls the motor based on a position of the actuator, The switch reduces the rotation speed of the motor during a no-load period when the ratchet gear is restricted from rotating in the first direction by the anti-reverse pawl, compared to a case where power is continuously supplied to the motor. A concave portion or a convex portion is formed on the outer edge of the cam, The actuator abuts against the concave portion or the convex portion during the no-load period, The contact portion is connected to a circuit that supplies power to the motor. When the actuator moves to a position abutting the recessed portion or the convex portion, the power supplied to the motor is reduced or made zero, thereby reducing the rotation speed of the motor during the no-load period compared to a case where power continues to be supplied to the motor.

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