Breaking mechanism portion of circuit breaker

Abstract

To provide a breaking mechanism portion of a circuit breaker that enables components to be made common between an AC circuit breakers and a DC circuit breaker.SOLUTION: An angle adjustment screw 38 is attached to a rotating member 31, the angle adjustment screw 38 being capable of adjusting the angle of inclination of the rotating member 31 with respect to a hanging plate 41 around an axis in a left-right direction. A normal posture of the rotating member 31 is set to a first normal position in which the rotating member 31 and the hanging plate 41 are approximately parallel to each other, whereby it is possible to configure an AC circuit breaker 1. A normal position of the rotating member 31 is set to a second normal position in which the rotating member 31 is tilted forward, whereby it is possible to configure a DC circuit breaker.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a breaking mechanism of a circuit breaker. [Background technology]

[0002] Conventionally known circuit breakers are equipped with a breaker mechanism including an electromagnetic tripping device that detects an excessive current such as a short circuit current flowing through an electric circuit and breaks the electric circuit (for example, Patent Document 1). Conventionally, AC circuit breakers and DC circuit breakers have different components that make up the breaker mechanism. First, this is due to the difference in the way that the coil that makes up the electromagnetic tripping device attracts the movable electromagnetic piece when an excessive current flows. Second, this is due to the difference in the value of the current that flows through the electric circuit of the circuit breaker when used at a rated current of, for example, 10A.

[0003] The first reason is that when an excessive current flows, in an AC circuit breaker, the movable electromagnetic piece separates from the coil every half cycle, resulting in multiple operations before the circuit breaker mechanism performs the circuit breaker operation, whereas in a DC circuit breaker, the movable electromagnetic piece operates only once. Therefore, the strength of the shock load required when the movable electromagnetic piece operates once differs between AC circuit breakers and DC circuit breakers, which is the reason why the parts that make up the circuit breaker mechanism are different between AC circuit breakers and DC circuit breakers.

[0004] The second reason is that, for example, when a DC circuit breaker is used at a rated current of 10A, the current flowing through the circuit in the circuit breaker is 10A, but in an AC circuit breaker, the current flowing through the circuit in the circuit breaker is √2 times that amount. Therefore, the moving electromagnetic piece of an AC circuit breaker is attracted to the coil with a stronger attraction force than the moving electromagnetic piece of a DC circuit breaker. Therefore, considering that the strength of the shock load required when the moving electromagnetic piece operates once as described above, is different between AC circuit breakers and DC circuit breakers, the second reason is also one of the reasons why the parts that make up the circuit breaker mechanism are different between AC circuit breakers and DC circuit breakers. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-179628 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, preparing separate parts for the breaking mechanism unit of an AC circuit breaker and the breaking mechanism unit of a DC circuit breaker results in a large number of parts, which in turn leads to higher costs for manufacturing and management, resulting in a problem of higher costs for the circuit breaker.

[0007] Therefore, the present invention has been made in consideration of the above problems, and aims to provide a breaking mechanism of a circuit breaker that enables components to be common between AC circuit breakers and DC circuit breakers. [Means for solving the problem]

[0008] In order to achieve the above object, the invention according to claim 1 of the present invention provides a circuit breaker having a power supply side terminal at the front and a load side terminal at the rear of a main body case, the circuit breaker comprising an electromagnetic tripping device which operates a movable electromagnetic piece when an excessive current flows in an electric circuit connecting the power supply side terminal and the load side terminal, and a common mechanism which performs an interruption operation in response to the operation of the movable electromagnetic piece, the circuit breaker interrupting mechanism performing an interruption operation of a handle for turning on / off the electric circuit in response to the interruption operation of the common mechanism, the common mechanism comprising a first interrupting member which changes its position from a normal position to an interruption position by rotating about an axis in the left-right direction, and a second interrupting member which changes its position from the normal position to the interruption position in response to the change in position of the first interrupting member, The blocking member is provided with an abutment portion that protrudes toward the second blocking member, while the second blocking member is provided with a hooking hole through which the abutment portion of the first blocking member in the blocking posture can be inserted, and further provided with an angle adjustment means that can adjust the inclination angle of the first blocking member relative to the second blocking member about an axis in the left-right direction, such that when the normal posture of the first blocking member is a first normal posture in which the inclination angle relative to the second blocking member is a first angle, the abutment portion abuts at a first position above the hooking hole, while when the normal posture of the first blocking member is a second normal posture in which the inclination angle relative to the second blocking member is a second angle, the abutment portion abuts at a position lower than the first position and close to the hooking hole. The invention described in claim 2 is characterized in that, in the invention described in claim 1, a screw hole penetrating the first blocking member from front to rear is drilled in the first blocking member, an angle adjustment screw is screwed into the screw hole, and an angle adjustment abutment portion against which the tip of the angle adjustment screw can abut is provided within the main body case, and the inclination angle of the first blocking member relative to the second blocking member can be adjusted by adjusting the amount of protrusion of the tip of the angle adjustment screw. Effect of the Invention

[0009] According to the present invention, an angle adjusting means is provided that can adjust the inclination angle of the first shutoff member relative to the second shutoff member about an axis in the left-right direction, and when the normal position of the first shutoff member is a first normal position in which the inclination angle relative to the second shutoff member is a first angle, the abutting portion abuts at a first position above the latch hole, while when the normal position of the first shutoff member is a second normal position in which the inclination angle relative to the second shutoff member is a second angle, the abutting portion abuts at a position lower than the first position and closer to the latch hole. Therefore, when the normal position of the first shutoff member is the first normal position, it can be configured as an AC circuit breaker, and when the normal position of the first shutoff member is the second normal position, it can be configured as a DC circuit breaker. Therefore, the parts of the shutoff mechanism can be shared between the AC circuit breaker and the DC circuit breaker, which can reduce the number of parts and the associated costs related to manufacturing and management. According to the invention described in claim 2, the first blocking member is provided with a screw hole penetrating the first blocking member from front to rear, an angle adjustment screw is screwed into the screw hole, and an angle adjustment abutment portion against which the tip of the angle adjustment screw can abut is provided inside the main body case, and the inclination angle of the first blocking member relative to the second blocking member can be adjusted by adjusting the amount of protrusion of the tip of the angle adjustment screw. Therefore, the inclination angle of the first blocking member relative to the second blocking member can be adjusted with a simple configuration, and it is possible to realize separate use as an AC circuit breaker and a DC circuit breaker. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is an explanatory diagram showing the appearance of an AC circuit breaker. [Diagram 2] FIG. 2 is a cross-sectional explanatory view showing the internal structure of the AC circuit breaker. [Diagram 3] 4 is an explanatory perspective view showing a breaking mechanism portion of the AC circuit breaker covered with a breaking mechanism cover, viewed from the right rear side. FIG. [Figure 4] 4 is a perspective explanatory view showing a breaking mechanism part of the AC circuit breaker covered with a breaking mechanism cover, viewed from the right front side. FIG. [Diagram 5]5 is a perspective explanatory view showing a state in which a handle and a blocking mechanism cover are omitted from FIG. 4. FIG. [Figure 6] FIG. 2 is an explanatory diagram showing a breaking mechanism part of an AC circuit breaker from the right side without a handle and a breaking mechanism cover. [Figure 7] FIG. 2 is an explanatory diagram showing an electromagnetic tripping device. [Figure 8] FIG. 4 is a perspective explanatory view showing the front side of the rotating member. [Figure 9] FIG. 4 is a perspective explanatory view showing the rear side of the rotating member. [Figure 10] FIG. [Figure 11] FIG. 4 is an explanatory diagram showing a linkage state between an electromagnetic tripping device and a rotating member in a normal state in an AC circuit breaker. [Figure 12] FIG. 4 is an explanatory diagram showing a linkage state between a rotating member and a hook plate in a normal state in the AC circuit breaker. [Figure 13] FIG. 2 is a cross-sectional explanatory view showing the internal structure of an AC circuit breaker that has performed a breaking operation. [Figure 14] FIG. 2 is an explanatory diagram showing a breaking mechanism of an AC circuit breaker performing a breaking operation, viewed from the right side. [Figure 15] 4 is an explanatory diagram showing a state of cooperation between a rotating member and a hook plate during a breaking operation of the AC circuit breaker. FIG. [Figure 16] FIG. 2 is an explanatory perspective view of a breaking mechanism of a DC circuit breaker, viewed from the right front side, with a handle and a breaking mechanism cover omitted. [Figure 17] FIG. 2 is an explanatory diagram showing a breaking mechanism part of a DC circuit breaker from the right side without the handle and the breaking mechanism cover. [Figure 18] FIG. 4 is an explanatory diagram showing a linkage state between a rotating member and a hook plate in a DC circuit breaker under normal conditions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A breaking mechanism of a circuit breaker according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0012] (AC Circuit Breaker Description) First, a case where it is configured as an AC circuit breaker 1 will be described. FIG. 1 is an explanatory diagram showing the appearance of an AC circuit breaker 1. FIG. 2 is a cross-sectional explanatory diagram showing the internal structure of the AC circuit breaker 1. FIG. 3 is an explanatory perspective view showing the breaker mechanism part of the AC circuit breaker 1 covered with the breaker mechanism cover 14 from the right rear side. FIG. 4 is an explanatory perspective view showing the breaker mechanism part of the AC circuit breaker 1 covered with the breaker mechanism cover 14 from the right front side. FIG. 5 is an explanatory perspective view showing a state in which the handle 11 and the breaker mechanism cover 14 are omitted from FIG. 4. FIG. 6 is an explanatory view showing the breaker mechanism part of the AC circuit breaker 1 from the right side without the handle 11 and the breaker mechanism cover 14. FIG. 7 is an explanatory view showing an electromagnetic tripping device 20. FIG. 8 is an explanatory perspective view showing the front side of the rotating member 31. FIG. 9 is an explanatory perspective view showing the rear side of the rotating member 31. FIG. 10 is an explanatory view showing a hook ply plate 41. Fig. 11 is an explanatory diagram showing the interlocking state between the electromagnetic tripping device 20 and the rotating member 31 in the AC circuit breaker 1 in normal operation. Fig. 12 is an explanatory diagram showing the interlocking state between the rotating member 31 and the latch plate 41 in the AC circuit breaker 1 in normal operation. Fig. 13 is a cross-sectional explanatory diagram showing the internal structure of the AC circuit breaker 1 that has performed a breaking operation. Fig. 14 is an explanatory diagram showing the breaking mechanism part of the AC circuit breaker 1 that has performed a breaking operation, from the right side. Fig. 15 is an explanatory diagram showing the interlocking state between the rotating member 31 and the latch plate 41 in the AC circuit breaker 1 during a breaking operation.

[0013] The AC circuit breaker 1 has a synthetic resin main body case with a cover member 3 attached to a base 2 so as to cover the upper part of the base 2, and the main body case is provided with a power source side terminal section 4 at the front and a load side terminal section 5 at the rear. The power source side terminal section 4 has two power source side terminals 4A, 4B arranged side by side on the left and right, while the load side terminal section 5 also has two load side terminals 5A, 5B arranged side by side on the left and right.

[0014] In addition, two electric circuits are arranged side by side in the main body case, a first electric circuit extending in the front-rear direction and connecting the power supply terminal 4A and the load terminal 5A, and a second electric circuit similarly connecting the power supply terminal 4B and the load terminal 5B. Each electric circuit has a first fixing bracket 6 extending forward from the load terminals 5A and 5B and serving as a component of the rear electric circuit. Each electric circuit also has a second fixing bracket 8 extending rearward from the power supply terminals 4A and 4B and constituting the front electric circuit, and a fixed contact 7 is provided at the rear end of the second fixing bracket 8. Furthermore, each electric circuit has a movable contact member 10 that electrically connects / disconnects the front electric circuit and the rear electric circuit. A movable contact 9 is provided at the front end of the movable contact member 10, and the movable contact member 10 moves the front end side up and down to bring the movable contact 9 into contact with / separate from the fixed contact 7.

[0015] Furthermore, a handle 11 that can be rotated in the forward and backward directions is provided on the top surface of the main body case, and a handle-side mechanism 12 is provided inside the main body case for operating the movable contact member 10 in response to the rotation of the handle 11 to turn the electric circuit on and off. In addition, an electromagnetic tripping device 20 is provided on the rear electric circuit of each electric circuit, which operates when an excessive current such as a short-circuit current flows through the electric circuit. A common mechanism 30 is provided on the front side of the electromagnetic tripping devices 20, 20 inside the main body case, which operates in response to the operation of the electromagnetic tripping device 20 and turns off the electric circuit by operating the movable contact member 10 via the handle-side mechanism 12. The handle-side mechanism 12 is covered by a circuit breaker cover 14.

[0016] In the AC circuit breaker 1, when an abnormal current or the like occurs and an excessive current flows, the electromagnetic tripping device 20 provided on the electric circuit on the side where the excessive current flows operates, and the common mechanism 30 operates in response to the operation of the electromagnetic tripping device 20. The operation of the common mechanism 30 also operates the handle side mechanism 12, and as a result, the movable contact members 10 operate in a direction in which the movable contacts 9 move away from the fixed contacts 7, and the electric circuit is interrupted.

[0017] Here, the electromagnetic tripping device 20 and the common mechanism section 30 constituting the interrupting mechanism section, which is the main part of the present invention, will be described. First, the electromagnetic tripping device 20 will be described. The electromagnetic tripping device 20 operates in the same manner as a known electromagnetic tripping device, and includes a yoke 21, a movable electromagnetic piece 22 attached to the yoke 21, a coil section 23 that generates an electromagnetic force for attracting the movable electromagnetic piece 22 when an excessive current flows, and a tension spring 24 that biases the movable electromagnetic piece 22 toward a side that moves away from the coil section 23 (toward a normal position, described later). The movable electromagnetic piece 22 is a metal piece that integrally includes an attracted piece 25 extending in the front-rear direction and a tongue piece 26 that extends downward from the front end of the attracted piece 25. The movable electromagnetic piece 22 is attached to the yoke 21 so that the tongue piece 26 tilts in the front-rear direction around the lower end of the tongue piece 26 as an axis, and as a result, the attracted piece 25 moves up and down while moving back and forth. In addition, an insertion hole 27 is provided from the front of the attracted piece 25 of the movable electromagnetic piece 22 to the upper part of the tongue piece 26, through which a collision target piece 36 of the rotating member 31 described later can be inserted. Furthermore, the tongue piece 26 is provided with an action protrusion 28 that protrudes upward and has a tip located within the insertion hole 27.

[0018] In the above-mentioned electromagnetic tripping device 20, the tongue 26 of the movable electromagnetic piece 22 is usually tilted forward and the attracted piece 25 is in a normal position (as shown in FIG. 2, FIG. 6, etc.) in which it is located above and away from the coil part 23. When an excessive current flows through the electric circuit, the attracted piece 25 is attracted to the coil part 23. Therefore, the movable electromagnetic piece 22, which was in the normal position, changes its position to an interruption position (as shown in FIG. 13, FIG. 14, etc.) in which the tongue 26 is tilted backward against the biasing force of the tension spring 24 and the attracted piece 25 approaches or comes into contact with the upper end of the coil part 23. With this change in position of the movable electromagnetic piece 22, the action protrusion 28 moves backward and collides with the front surface of the collided piece 36, thereby changing the position of the rotating member 31. As described in the background art, in the AC circuit breaker 1, the attracted piece 25 is intermittently attracted multiple times when an excessive current flows through the electric circuit. Therefore, the movable electromagnetic piece 22 repeatedly changes its position between the normal position and the interrupted position, and as a result, the action projection 28 repeatedly collides with the collision target piece 36 .

[0019] Next, the common mechanism 30 will be described. The common mechanism 30 includes a rotating member 31 that changes its position by rotating about an axis in the left-right direction, and a hook plate 41 that changes its position by tilting about an axis in the left-right direction as the rotating member 31 changes its position. The main body of the rotating member 31 is formed in a plate shape that is long in the left-right direction, and the rotating member 31 is disposed across two electric circuits disposed in the main body case. In addition, the front surface of the rotating member 31 is provided with rotating shaft support parts 33, 33 and a shaft hole 34 for supporting a rotating shaft 32 (shown in FIG. 3, etc.) extending in the left-right direction. Furthermore, a holding piece 35 formed in a plate shape with a thickness direction in the left-right direction is provided on the front surface of the rotating member 31 so as to protrude forward. Furthermore, the lower part of the rotating member 31 is provided with collision receiving pieces 36, 36 protruding downward, and the right collision receiving piece 36 can be inserted from above into the insertion hole 27 of the electromagnetic tripping device 20 arranged on the first electric circuit connecting the power supply side terminal 4A and the load side terminal 5A, and the left collision receiving piece 36 can be inserted from above into the insertion hole 27 of the electromagnetic tripping device 20 arranged on the second electric circuit connecting the power supply side terminal 4B and the load side terminal 5B. In addition, a screw hole 37 is drilled in the lower right corner of the rotating member 31 so as to penetrate the rotating member 31 from the front to the rear. An angle adjustment screw 38 for adjusting the inclination angle of the rotating member 31 with respect to the hook plate 41 in the normal position is attached to the screw hole 37 with its tip screwed in from the rear side of the rotating member 31 as described later.

[0020] The above-mentioned rotating member 31 is assembled with the rotating shaft 32 supported by the rotating shaft support portion 33 and the shaft hole 34, and each collision-receiving piece 36 inserted from above into the corresponding insertion hole 27 of the electromagnetic tripping device 20. In each insertion hole 27, the collision-receiving piece 36 is located behind the action protrusion 28 and on the movement path of the action protrusion 28 during the interruption operation of the electromagnetic tripping device 20. The angle adjustment screw 38 is screwed into the screw hole 37 such that the tip of the angle adjustment screw 38 does not protrude forward from the screw hole 37 or is flush with the front surface of the rotating member 31. The rotating member 31 is urged toward the normal position by a spring 39 (shown in Figs. 2, 6, etc.) in a first normal position in which the rotating member 31 stands almost vertically and the holding piece 35 protrudes almost horizontally to the front side, and the inclination angle with respect to the hook plate 41 in the normal position described later is a first angle. When an excessive current flows in the electric circuit and the electromagnetic tripping device 20 performs an interruption operation, the action protrusion 28 repeatedly hits the collision target piece 36. Therefore, the rotating member 31 rotates about the rotation shaft 32 against the urging force of the spring 39, and changes its position to an interruption position in which the collision target pieces 36, 36 extend diagonally downward to the rear and the holding piece 35 is inclined diagonally downward to the front. After the position is changed to the interruption position, the holding piece 35 is hooked to a hook hole 44 of the hook plate 41 described later, and the rotating member 31 is held in the interruption position.

[0021] On the other hand, the hook plate 41 is formed in a plate shape with the thickness direction being the front-rear direction, and the lower end is provided with tilting shaft support parts 43, 43 for supporting the tilt shaft 42 extending in the left-right direction. A hook hole 44 is opened in the upper part of the hook plate 41. The upper edge of the hook hole 44 is formed in a straight line extending substantially horizontally. On the rear surface of the hook plate 41, a part on the upper right side of the hook hole 44 serves as an action surface 45, against which the tip of the holding piece 35 in the normal position abuts. Also, as shown in FIG. 2 and FIG. 5, the part on the upper side of the hook hole 44 to the left of the action surface 45 functions as a hooked part 48 to which the hook piece 13, which is a component of the handle side mechanism part 12, is normally hooked, as shown in FIG.

[0022] The hanging plate 41 as described above is assembled in a state where the tilting shaft 42 is supported by the tilting shaft support part 43 at the front side of the rotating member 31, particularly at the front side of the holding piece 35. The hanging plate 41 is in a normal position in which it stands up substantially vertically, and is biased toward the blocking position, which will be described later, by a torsion spring 49 (shown in FIG. 6, etc.). As shown in FIG. 12, the tip of the holding piece 35 abuts against an action surface 45 of the hanging plate 41 in the normal position, and the tip of the holding piece 35 presses against the action surface 45 by the biasing force of the spring 39 which biases the rotating member 31 toward the normal position and the torsion spring 49 which biases the hanging plate 41 toward the blocking position, thereby holding the hanging plate 41 in the normal position. When an excessive current flows through the electric circuit and the rotating member 31 changes its position to the cut-off position, the tip of the holding piece 35 moves downward on the action surface 45, and finally moves away from the action surface 45 and into the hook hole 44. Therefore, the hook plate 41 tilts rearward about the tilt shaft 42 due to the urging force of the torsion spring 49, and changes its position to the cut-off position, which is a rearward tilted position toward the rotating member 31. In addition, as the hook plate 41 changes its position, the hooking piece 13 and the hook plate 41 are released, so that the handle side mechanism 12 performs a cut-off operation and the electric circuit is turned off. In addition, as the hook plate 41 changes its position to the cut-off position, the holding piece 35 penetrates the hook hole 44, and the upper surface of the holding piece 35 and the upper edge of the hook hole 44 are hooked as shown in FIG. 15.

[0023] Here, a series of operations of the electromagnetic tripping device 20 and the common mechanism section 30 when an excessive current flows through the electric circuit in the AC circuit breaker 1 will be described. When an excessive current flows through the electric circuit, the electromagnetic tripping device 20 performs an interruption operation. That is, the attracted piece 25 is intermittently attracted to the coil portion 23, and the movable electromagnetic piece 22 repeatedly changes its position between the normal position and the interruption position. Therefore, the action projection 28 repeatedly collides with the collision piece 36, and as a result, the rotating member 31 changes its position from the first normal position to the interruption position. With this change in position of the rotating member 31, the tip of the holding piece 35 moves downward on the action surface 45, and finally moves away from the action surface 45 into the hook hole 44, and as a result, the hooking plate 41 changes its position from the normal position to the interruption position. With this change in position of the hooking plate 41, the engagement between the hooking piece 13 and the hooking plate 41 is released, and the handle side mechanism portion 12 performs an interruption operation to turn off the electric circuit.

[0024] (DC Circuit Breaker Description) Next, a case where the circuit breaker is configured as a DC circuit breaker will be described. Fig. 16 is an explanatory perspective view showing the breaking mechanism of the DC circuit breaker from the right front side, with the handle 11 and the breaking mechanism cover 14 omitted. Fig. 17 is an explanatory view showing the breaking mechanism of the DC circuit breaker from the right side, with the handle 11 and the breaking mechanism cover 14 omitted. Fig. 18 is an explanatory view showing the linkage state between the rotating member 31 and the hook plate 41 in the DC circuit breaker under normal conditions.

[0025] The DC circuit breaker is composed of substantially the same components as the AC circuit breaker 1, and also includes an electromagnetic tripping device 20 and a common mechanism 30 as a breaking mechanism section. However, the DC circuit breaker and the AC circuit breaker 1 differ in the normal position of the rotating member 31, and further, the angle of the rotating member 31 relative to the latch plate 41 in the normal position.

[0026] The difference in the angle of the rotating member 31 relative to the hook plate 41 is due to the difference in the screwing state of the angle adjustment screw 38 into the screw hole 37. That is, in the rotating member 31 of the DC circuit breaker, the angle adjustment screw 38 is screwed deeper into the screw hole 37 than in the AC circuit breaker 1, and the tip of the angle adjustment screw 38 protrudes a predetermined amount forward of the rotating member 31. The tip of the angle adjustment screw 38 is in a state of abutment against the angle adjustment abutment part 15 which is a part of the breaker mechanism cover 14 and is located in front of the angle adjustment screw 38. Therefore, the normal position of the rotating member 31 in the DC circuit breaker is inclined further forward than the first normal position in the AC circuit breaker 1, and is a second normal position in which the inclination angle relative to the hook plate 41 is a second angle. The screwing state of the angle adjustment screw 38 into the screw hole 37 is adjusted before assembly into the main body case, and the screwing state of the angle adjustment screw 38 is not adjusted after assembly.

[0027] Even in the second normal position as described above, the tip of the retaining piece 35 of the rotating member 31 abuts against the action surface 45 and presses the latch plate 41 forward. However, the abutment position of the retaining piece 35 on the action surface 45 is lower than the abutment position in the AC circuit breaker 1 and closer to the latch hole 44 as shown in FIG. 18. Therefore, in the DC circuit breaker, the movement amount of the retaining piece 35 until it enters the latch hole 44, i.e., the movement amount of the retaining piece 35 until the retention of the latch plate 41 by the retaining piece 35 is released, is shorter than in the AC circuit breaker. Therefore, in the DC circuit breaker, the retaining piece 35 enters the latch hole 44 more quickly and more easily, and the rotating member 31 changes its position to the same interrupting position as in the AC circuit breaker 1, and the latch plate 41 changes its position to the same interrupting position as in the AC circuit breaker 1 by the biasing force of the torsion spring 49.

[0028] Here, a series of operations of the electromagnetic tripping device 20 and the common mechanism section 30 when an excessive current flows through the electric circuit in the DC circuit breaker will be described. When an excessive current flows through the electric circuit, the electromagnetic tripping device 20 performs an interruption operation. That is, the attracted piece 25 is attracted to the coil portion 23, and the movable electromagnetic piece 22 changes its position from the normal position to the interruption position. Therefore, the action projection 28 collides with the collision piece 36 only once. However, as described above, the tip of the holding piece 35 abuts on the action surface 45 at a position close to the hook hole 44, so that the rotation member 31 surely changes its position from the second normal position to the interruption position with one collision. Then, with this change in position of the rotation member 31, the hooking plate 41 changes its position from the normal position to the interruption position, so that the hooking piece 13 and the hooking plate 41 are released from the engagement, and the handle side mechanism portion 12 performs an interruption operation to turn off the electric circuit.

[0029] According to the interrupting mechanism of the circuit breaker having the electromagnetic tripping device 20 and the common mechanism 30 as described above, the common mechanism 30 includes the rotating member 31 which changes its position from the normal position to the interrupting position by rotating about an axis in the left-right direction, and the hooking plate 41 which changes its position from the normal position to the interrupting position in response to the change in position of the rotating member 31. The rotating member 31 is provided with a holding piece 35 which protrudes toward the hooking plate 41, while the hooking plate 41 is provided with a hooking hole 44 through which the holding piece 35 of the rotating member 31 in the interrupting position can be inserted. Furthermore, the rotating member 31 is provided with an angle adjustment screw 38 which can adjust the inclination angle of the rotating member 31 relative to the hooking plate 41 about an axis in the left-right direction. The AC circuit breaker 1 can be configured by setting the normal position of the rotating member 31 to a first normal position in which the rotating member 31 and the latch plate 41 are approximately parallel, while the DC circuit breaker can be configured by setting the normal position of the rotating member 31 to a second normal position in which the rotating member 31 is tilted forward. Therefore, the AC circuit breaker 1 and the DC circuit breaker can share the same parts in the breaking mechanism, thereby reducing the number of parts and the associated costs related to manufacturing and management.

[0030] Further, the rotating member 31 is provided with a screw hole 37 penetrating the rotating member 31 from front to rear, an angle adjustment screw 38 is screwed into the screw hole 37, and an angle adjustment abutment portion 15 against which the tip of the angle adjustment screw 38 can abut is provided on the breaking mechanism cover 14 covering the handle side mechanism portion 12, so that the inclination angle of the rotating member 31 in the normal position relative to the hanging plate 41 can be adjusted by adjusting the amount of protrusion of the tip of the angle adjustment screw 38. Therefore, the inclination angle of the rotating member 31 in the normal position relative to the hanging plate 41 can be adjusted with a simple configuration, and thus it is possible to realize different uses for the AC circuit breaker 1 and the DC circuit breaker.

[0031] The circuit breaker mechanism of the circuit breaker according to the present invention is not limited to the above-described embodiment, and the configurations of the electromagnetic tripping device, the control mechanism related to the common mechanism, etc. may be appropriately modified as necessary without departing from the spirit of the present invention.

[0032] For example, in the above embodiment, one rotating member and hanging plate are used to correspond to the left and right electrical circuits, but the rotating member may be composed of multiple parts, or a rotating member and hanging plate may be provided for each electrical circuit. In the above embodiment, the angle adjustment means is provided on the rotating member, but the angle adjustment means may be provided on the hook plate instead of the rotating member, or on both the rotating member and the hook plate. On the other hand, the angle adjustment means may be provided on the blocking mechanism cover, and the design of where to provide the angle adjustment means can be changed as appropriate.

[0033] Furthermore, in the above embodiment, when the rotating member is in the first normal position, the tip of the angle adjustment screw does not protrude forward from the screw hole or is flush with the front surface of the rotating member, and the inclination angle at which the rotating member and the hook plate are substantially parallel (i.e., the inclination angle of the rotating member with respect to the hook plate is 0°) is set as the first angle, but the tip of the angle adjustment screw may also protrude forward from the screw hole at the first angle, and the rotating member may be configured to take a forward inclined position in the first normal position. In other words, the specific degrees of the first angle and the second angle can be appropriately changed in design. In addition, in the above embodiment, a screw hole and an angle adjustment screw are used as the angle adjustment means, but the specific configuration of the angle adjustment means can also be appropriately designed and modified, for example, by providing a protrusion at the tip of the retaining piece of the rotating member, while providing multiple recesses in the vertical direction on the hanging plate into which the protrusion can be engaged, and by varying the position of the recesses into which the protrusion is engaged, it is possible to adjust the inclination angle of the rotating member relative to the hanging plate in the normal position. [Explanation of symbols]

[0034] 1...AC circuit breaker (circuit breaker), 11...handle, 12...handle side mechanism (breaker mechanism), 13...hook (breaker mechanism), 14...breaker mechanism cover, 15...angle adjustment abutment (angle adjustment means), 20...electromagnetic tripping device, 22...movable electromagnetic piece, 28...acting protrusion, 30...common mechanism, 31...rotating member (first breaking member), 32...rotating shaft, 35...holding piece (abutment), 37...screw hole (angle adjustment means), 38...angle adjustment screw (angle adjustment means), 41...hook plate (second breaking member), 44...hook hole, 45...acting surface.

Claims

1. A circuit breaker having a power supply side terminal at the front of a main body case and a load side terminal at the rear of the main body case, the circuit breaker comprising: an electromagnetic tripping device which operates a movable electromagnetic contact when an excessive current flows in an electric path connecting the power supply side terminal and the load side terminal; and a common mechanism which performs an interruption operation in response to the operation of the movable electromagnetic contact, A circuit breaker mechanism for a circuit breaker that performs a break operation on a handle for turning on / off the electric circuit in response to a break operation of the common mechanism, The common mechanism includes a first blocking member that changes its position from a normal position to a blocking position by rotating about an axis in the left-right direction, and a second blocking member that changes its position from the normal position to the blocking position in response to the change in position of the first blocking member, the first blocking member is provided with a contact portion that protrudes toward the second blocking member, while the second blocking member is provided with a hook hole through which the contact portion of the first blocking member in a blocking posture can be inserted, Further, an angle adjustment means is provided that can adjust an inclination angle of the first blocking member relative to the second blocking member about an axis in the left-right direction, When the normal posture of the first blocking member is a first normal posture in which the inclination angle with respect to the second blocking member is a first angle, the abutment portion abuts on a first position that is above the engagement hole, A circuit breaker breaking mechanism portion characterized in that when the normal position of the first breaking member is a second normal position in which the inclination angle relative to the second breaking member is a second angle, the abutment portion abuts at a position lower than the first position and closer to the engagement hole.

2. a screw hole penetrating the first blocking member from front to rear is drilled in the first blocking member, an angle adjustment screw is screwed into the screw hole, and an angle adjustment abutment portion against which a tip of the angle adjustment screw can abut is provided in the main body case, 2. The circuit breaker breaking mechanism according to claim 1, wherein the inclination angle of the first breaking member relative to the second breaking member is adjustable by adjusting the amount of protrusion of the tip of the angle adjustment screw.

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