Vacuum circuit breaker and electrically controlled permanent-magnetic bistable operating mechanism thereof

Abstract

The application belongs to the technical field of electrical equipment, and discloses a vacuum circuit breaker and an electric control permanent magnetic bistable operating mechanism thereof. The electric control permanent magnetic bistable operating mechanism comprises: an upper suction unit and a lower suction unit which are fixed and oppositely arranged, each of the suction units is provided with a yoke, a permanent magnet and an excitation coil; the permanent magnet and the excitation coil are located in the yoke; a moving iron core is movably arranged between the upper suction unit and the lower suction unit; a transmission rod is arranged on the moving iron core to be driven to move by the moving iron core, and one end of the transmission rod is arranged in the upper suction unit and connected with an insulating connecting rod. The vacuum circuit breaker comprises: a permanent magnetic mechanism which is the electric control permanent magnetic bistable operating mechanism; and an insulating pull rod which is connected with the permanent magnetic mechanism at one end and connected with a movable contact of an arc extinguishing chamber of the vacuum circuit breaker at the other end. The above scheme makes the mechanism have the advantages of simple structure, easy processing, low cost, convenient control, stable operation and the like.

Description

Technical Field

[0001] This invention belongs to the field of electrical equipment technology, and specifically relates to a vacuum circuit breaker and its electrically controlled permanent magnet bistable operating mechanism. Background Technology

[0002] Existing permanent magnet mechanisms utilize permanent magnets as magnetic poles and an iron core as the moving part. Under the action of an excitation coil, the iron core detaches from the attraction of one permanent magnet pole and moves to the pole of another, completing the transition from one steady state to another, with the iron core exhibiting linear motion. During the reverse motion, the excitation coil is energized with a reverse current, changing the magnetic field and causing the iron core to move from one pole to another. Throughout this process, the intrinsic magnetic properties of the two permanent magnets remain unchanged; only the superposition of the magnetic fields from the excitation coils causes one magnetic field to decrease while the other increases, attracting the iron core from one position to another. After excitation, the attraction between the iron core and the nearest magnet is much greater than that of the far magnet, allowing the iron core to remain in a stable state under the influence of the nearest magnet.

[0003] While this is true in theory, in practice, permanent magnet mechanisms manufactured based on this theory are complex in structure, difficult to process, costly, inconvenient to control, and have poor operational stability. Summary of the Invention

[0004] To address the above problems, the present invention provides an electrically controlled permanent magnet bistable operating mechanism, comprising:

[0005] An upper suction unit and a lower suction unit are fixed and arranged opposite to each other. Each suction unit has: a yoke, a permanent magnet, and an excitation coil; the permanent magnet and the excitation coil are both located inside the yoke.

[0006] A movable iron core is movably disposed between the upper suction unit and the lower suction unit;

[0007] A transmission rod is mounted on the moving iron core and is driven to move by the moving iron core. One end of the transmission rod passes through the upper suction unit and is connected to the insulating connecting rod.

[0008] Optionally, in the electrically controlled permanent magnet bistable operating mechanism described above, the mechanism further includes:

[0009] A closing buffer spring is located inside the upper suction unit, and one end of the closing buffer spring is connected to the upper suction unit.

[0010] In the electrically controlled permanent magnet bistable operating mechanism described above, optionally, the other end of the transmission rod passes through the lower suction unit and is connected to a position switch, which is used to characterize the contact position information of the circuit breaker's arc-extinguishing chamber.

[0011] Optionally, in the electrically controlled permanent magnet bistable operating mechanism described above, the mechanism further includes:

[0012] The tripping buffer spring is located inside the lower suction unit, and one end of the tripping buffer spring is connected to the lower suction unit.

[0013] In the electrically controlled permanent magnet bistable operating mechanism described above, optionally, a first groove is provided on the side of the moving iron core facing the upper suction unit, and when the circuit is closed, the first groove contains a part of the excitation coil of the upper suction unit.

[0014] In the electrically controlled permanent magnet bistable operating mechanism described above, optionally, a second groove is provided on the side of the moving iron core facing the lower suction unit, and when the circuit is opened, the second groove contains a part of the excitation coil of the lower suction unit.

[0015] In the electrically controlled permanent magnet bistable operating mechanism described above, optionally, the permanent magnet is sleeved outside the transmission rod and located inside the excitation coil.

[0016] In the electrically controlled permanent magnet bistable operating mechanism described above, optionally, the transmission rod is divided into an upper transmission rod and a lower transmission rod;

[0017] The upper transmission rod is disposed on the side of the moving iron core facing the upper suction unit;

[0018] The lower transmission rod is disposed on the side of the moving iron core facing the lower suction unit, and the other end of the lower transmission rod passes through the lower suction unit.

[0019] Optionally, in the electrically controlled permanent magnet bistable operating mechanism described above, the mechanism further includes:

[0020] The connecting sleeve is ring-shaped and is fitted onto the outside of the upper suction unit and the lower suction unit.

[0021] Another aspect of the present invention provides a vacuum circuit breaker, comprising:

[0022] The permanent magnet operating mechanism is the aforementioned electrically controlled permanent magnet bistable operating mechanism;

[0023] An insulating pull rod, one end of which is connected to the permanent magnet mechanism, and the other end of which is connected to the moving contact of the arc-extinguishing chamber of the vacuum circuit breaker.

[0024] In the vacuum circuit breaker described above, optionally, the closing buffer spring located in the upper suction unit of the electrically controlled permanent magnet bistable operating mechanism is replaced by the contact pressure spring of the arc-extinguishing chamber of the vacuum circuit breaker.

[0025] The beneficial effects of the technical solution provided by the embodiments of the present invention are as follows:

[0026] By setting up an upper suction unit, a lower suction unit, a moving iron core, and a transmission rod, the upper and lower suction units are fixedly arranged and opposite to each other. The moving iron core is located between the upper and lower suction units and moves relative to either the upper or lower suction unit. The transmission rod is set on the moving iron core and is driven to move by the moving iron core. One end of the transmission rod passes through the upper suction unit to connect with the insulating connecting rod. This makes the structure of the electrically controlled permanent magnet bistable operating mechanism simple, easy to process, low in cost, convenient to control, and stable in operation. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of an electrically controlled permanent magnet bistable operating mechanism (in the closed state) provided in an embodiment of the present invention.

[0029] Figure 2 This is a schematic diagram of the closing excitation of an electrically controlled permanent magnet bistable operating mechanism (in the closed state) provided in an embodiment of the present invention.

[0030] Figure 3 This is a schematic diagram of an electrically controlled permanent magnet bistable operating mechanism (in the open state) provided in an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the opening excitation of an electrically controlled permanent magnet bistable operating mechanism (in the opening state) provided in an embodiment of the present invention.

[0032] The symbols in the diagram are explained as follows:

[0033] 1-Upper transmission rod, 2-Upper yoke, 3-Closing buffer spring, 4-Closing permanent magnet, 5-Closing excitation coil, 6-Connecting sleeve, 7-Moving iron core, 8-Closing buffer spring, 9-Closing permanent magnet, 10-Closing excitation coil, 11-Lower yoke, 12-Lower transmission rod, 13-Screw, N-N pole of permanent magnet, S-S pole of permanent magnet, n-N pole of excitation coil magnetic field line, s-S pole of excitation coil magnetic field line. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation and not by way of limitation. Indeed, those skilled in the art will recognize that modifications and variations can be made to the invention without departing from its scope or spirit. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the invention encompass such modifications and variations falling within the scope of the appended claims and their equivalents.

[0035] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected," "linked," and "set up" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a direct connection or an indirect connection through intermediate components; a wired connection, a radio connection, or a wireless communication signal connection. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0036] See Figures 1-4 This invention provides an electrically controlled permanent magnet bistable operating mechanism, which includes: an upper suction unit, a lower suction unit, a moving iron core 7, and a transmission rod.

[0037] The upper suction unit and the lower suction unit are arranged opposite each other, such as Figure 1 In this configuration, the two units are vertically aligned, one above the other. As units providing attraction to the moving iron core 7, they must remain stationary, meaning they need to be fixed in place. Each attraction unit comprises: a yoke, a permanent magnet, and an excitation coil. The permanent magnet and excitation coil are both located within the yoke. Accordingly, the upper attraction unit includes: an upper yoke 2, an upper permanent magnet (or closing permanent magnet 4), and an upper excitation coil (or closing excitation coil 5). The lower attraction unit includes: a lower yoke 11, a lower permanent magnet (or opening permanent magnet 9), and a lower excitation coil (or opening excitation coil 10). To achieve simultaneous attraction in opposite directions from both the upper and lower attraction units, the excitation coils of the upper and lower attraction units are connected in series or in parallel in reverse order. The moving iron core 7 is positioned between the upper suction unit and the lower suction unit, and is movable relative to either the upper or lower suction unit. The direction of movement is the connection direction between the upper and lower suction units. Figure 1The transmission rod is mounted on the moving iron core 7 and passes through the upper suction unit, with one end of the transmission rod protruding from the upper suction unit to connect with the insulating connecting rod. It can then move under the drive of the moving iron core 7, thereby moving the insulating connecting rod and realizing the movement of the moving contact, i.e., closing or opening the circuit breaker. The height of the permanent magnet within the suction unit can be higher than the height of the excitation coil within the suction unit. The end face of the permanent magnet facing the moving iron core 7 is flush with the end face of the yoke facing the moving iron core 7.

[0038] During the closing operation, current is simultaneously supplied to the closing excitation coil 5 and the opening excitation coil 10. The closing excitation coil 5 is supplied with a positive current, and the direction of the magnetic field lines is the same as that of the closing permanent magnet 4. The upper magnetic field is enhanced, and the moving iron core 7 is subjected to a strong upward attraction force. Simultaneously, a reverse current is supplied to the tripping excitation coil 10, and the direction of the magnetic field lines is opposite to that of the tripping permanent magnet 9. The lower magnetic field weakens, and the downward attraction force on the moving iron core 7 is greatly reduced, or even zero. With the assistance of the excitation of the closing excitation coil 5 and the attraction force of the closing permanent magnet 4, the moving iron core 7 moves upward. Through the transmission rod, it drives the insulating connecting rod to move upward, which in turn drives the moving contact of the arc-extinguishing chamber to move upward. After the closing action is completed, the control unit automatically cuts off the excitation current of the tripping excitation coil 10 and the excitation current of the closing excitation coil 5. The moving iron core 7 is held in the closed position by the attraction force of the closing permanent magnet 4. At this time, although the tripping permanent magnet 9 also shows magnetism, because it is far away from the moving iron core 7 relative to the closing permanent magnet 4, the attraction force on the moving iron core 7 is much smaller than the attraction force of the closing permanent magnet 4. Therefore, it will not interfere with the position holding of the moving iron core 7.

[0039] During the tripping operation, current is simultaneously applied to the closing excitation coil 5 and the tripping excitation coil 10. The tripping excitation coil 10 is supplied with a positive current, and the direction of the magnetic field lines is the same as that of the tripping permanent magnet 9. The lower magnetic field is enhanced, and the moving iron core 7 is subjected to a strong downward attraction force. Simultaneously, a reverse current is supplied to the closing excitation coil 5, and the direction of the magnetic field lines is opposite to that of the closing permanent magnet 4. The upper magnetic field weakens, and the upward attraction force on the moving iron core 7 is greatly reduced, or even zero. With the assistance of the excitation of the opening excitation coil 10 and the attraction force of the opening permanent magnet 9, the moving iron core 7 moves downward. Through the transmission rod, it drives the insulating connecting rod to move downward, which in turn drives the moving contact of the arc-extinguishing chamber to move downward. After the opening action is completed, the control unit automatically cuts off the excitation current of the opening excitation coil 10 and the closing excitation coil 5. The moving iron core 7 is held in the opening position by the attraction force of the opening permanent magnet 9. At this time, although the closing permanent magnet 4 also shows magnetism, because it is farther away from the moving iron core 7 than the opening permanent magnet 9, the attraction force on the moving iron core 7 is much smaller than the attraction force of the opening permanent magnet 9. Therefore, it will not interfere with the position holding of the moving iron core 7.

[0040] By setting up an upper suction unit, a lower suction unit, a moving iron core 7, and a transmission rod, the upper and lower suction units are fixedly set and opposite to each other. The moving iron core 7 is located between the upper and lower suction units and moves relative to either the upper or lower suction unit. The transmission rod is set on the moving iron core 7 and is driven to move by the moving iron core 7. One end of the transmission rod passes through the upper suction unit to connect with the insulating connecting rod, making the structure of this electrically controlled permanent magnet bistable operating mechanism simple, easy to process, low in cost, convenient to control, and stable in operation.

[0041] When the circuit breaker closes, the instantaneous impact force is relatively large, especially near the final closing position. To reduce the closing speed and buffer the mechanical impact force, this electrically controlled permanent magnet bistable operating mechanism also includes a closing buffer spring 3, which is located within the upper suction unit. One end of the closing buffer spring 3 is connected to the yoke of the upper suction unit, so that the closing buffer spring 3 can be compressed by the upward movement of the transmission rod during closing. Under the action of the closing buffer spring 3, the closing speed is reduced. When switching from the closing state to the opening state, the transmission rod will move downward. At this time, the closing buffer spring 3 will release the assistance that causes the moving iron core 7 to move downward. That is, under the excitation of the opening excitation coil 10, the attraction force of the opening permanent magnet 9, and the assistance of the closing buffer spring 3, the moving iron core 7 moves downward, improving the stability of the mechanism's operation. Specifically, an upper shoulder can be formed on the body of the transmission rod, and an upper groove can be formed on the side of the upper yoke 2 facing the moving iron core 7. An upper through hole is opened at the bottom of the upper groove, and the shoulder is movably disposed within the upper groove. One end of the closing buffer spring 3 is connected to the bottom of the upper groove. The outer diameter of the closing buffer spring 3 is larger than the inner diameter of the upper through hole. The upper end of the transmission rod body passes through the upper through hole and is connected to the insulating connecting rod, and the lower end of the transmission rod body is connected to the moving iron core 7. In other embodiments, the closing buffer spring 3 can be located within the upper suction unit by connecting to the transmission rod. When the closing buffer spring 3 is in the open state, its free length can be less than the distance between the bottom of the upper groove and the upper end face of the upper shoulder. When the opening buffer spring 8 is in the closed state, its free length can be less than the distance between the bottom of the lower groove formed on the side of the lower yoke 11 facing the moving iron core 7 and the lower end face of the lower shoulder formed on the body of the transmission rod. The lower shoulder and the upper shoulder are located on opposite sides of the moving iron core 7.

[0042] To facilitate timely understanding of whether the mechanism is in an open or closed state, the other end of the transmission rod passes through the lower suction unit and is connected to a position switch. The position switch is used to indicate the contact position information of the circuit breaker's arc-extinguishing chamber. When the other end is in contact with the first position switch, it indicates that the circuit is in a closed state, and when it is in contact with the second position switch, it indicates that the circuit is in an open state.

[0043] When the circuit breaker is opened, the instantaneous impact force is relatively large, especially near the final opening position. To reduce the opening speed and buffer the mechanical impact force, this electrically controlled permanent magnet bistable operating mechanism also includes a opening buffer spring 8, which is located within the lower suction unit. One end of the opening buffer spring 8 is connected to the yoke of the lower suction unit, so that the opening buffer spring 8 can be compressed by the downward movement of the transmission rod during opening. Under the action of the opening buffer spring 8, the opening speed is reduced. When switching from the opening state to the closing state, the transmission rod moves upward. At this time, the opening buffer spring 8 releases the assistance that causes the moving iron core 7 to move upward. That is, under the excitation of the closing excitation coil 5, the attraction force of the closing permanent magnet 4, and the assistance of the opening buffer spring 8, the moving iron core 7 moves upward, improving the stability of the mechanism's operation. In other embodiments, the opening buffer spring 8 can be located within the lower suction unit by connecting it to the transmission rod. It should be noted that the opening buffer spring 8 can be in a free state, i.e., in an uncompressed state, when either the closing buffer spring 3 is in the closed state or the opening buffer spring 3 is in the open state. The closing buffer spring 3 is connected to the transmission rod or the yoke of the upper suction unit, and the connection between the opening buffer spring 8 and the transmission rod or the lower suction unit can be an abutment connection, i.e., a contact connection, or a welding connection, etc. This embodiment does not limit this.

[0044] To further enhance the assist during the closing state, the moving iron core 7 of this electrically controlled permanent magnet bistable operating mechanism has a first groove on the side facing the upper suction unit. This groove is used to accommodate a portion of the excitation coil of the upper suction unit; in other words, the other portion of the excitation coil is located within the upper yoke 2. Figure 1 In this configuration, the lower part of the excitation coil is located within the first groove. Specifically, in the closed state, the lower end of the excitation coil is located within the first groove; in the open state, the lower end of the excitation coil may also be located within the first groove or be spaced apart from the end face where the groove opening of the first groove is located.

[0045] To further enhance the assist during the tripping state, the moving iron core 7 of this electrically controlled permanent magnet bistable operating mechanism has a second groove on the side facing the lower suction unit. This groove accommodates a portion of the excitation coil of the lower suction unit; in other words, the other portion of the excitation coil is located within the lower yoke 11. Figure 1 In this configuration, the lower part of the excitation coil is located within the second groove. Alternatively, in the open state, the upper end of the excitation coil may be located within the second groove; in the closed state, the upper end of the excitation coil may also be located within the second groove or spaced apart from the end face where the slot opening of the second groove is located. The relative positions of the second groove and the first groove provide operational stability. Both are annular in shape.

[0046] The permanent magnet is fitted between the transmission rod and the excitation coil. That is to say, the transmission rod, the permanent magnet and the excitation coil are arranged in the radial direction from the inside to the outside.

[0047] The transmission rods are divided into an upper transmission rod 1 and a lower transmission rod 12. The upper transmission rod 1 is located on the upper end face of the moving iron core 7, that is, on the side of the moving iron core 7 facing the upper suction unit, and one end (or top end) of the upper transmission rod 1 passes through the upper suction unit. The lower transmission rod 12 is located on the lower end face of the moving iron core 7, that is, on the side of the moving iron core 7 facing the lower suction unit, and the lower end of the lower transmission rod 12 passes through the lower suction unit. There is no connection between the two transmission rods, i.e., there is a gap between them and the upper transmission rod 1, making the upper transmission rod 1 and the lower transmission rod 12 two independent rods, which facilitates the assembly of this mechanism. In other embodiments, the upper transmission rod 1 and the lower transmission rod 12 can be a single transmission rod. The other end of the lower transmission rod 12 passes through the lower suction unit. The upper transmission rod 1 and the lower transmission rod 12 are arranged opposite each other, further improving the stability of movement. Specifically, a first through hole is provided on the moving iron core 7, and both the upper transmission rod 1 and the lower transmission rod 12 are located within the first through hole. A lower shoulder can be formed on the body of the lower transmission rod 12, and a lower groove can be formed on the side of the lower yoke 11 facing the moving iron core 7. A lower through hole is opened at the bottom of the lower groove, the lower shoulder is movably set in the lower groove, the lower end face of the lower shoulder is connected to one end of the trip buffer spring 8, the other end of the trip buffer spring 8 is connected to the bottom of the lower groove, the outer diameter of the trip buffer spring 8 is larger than the inner diameter of the lower through hole, the lower end of the body of the lower transmission rod 12 passes through the lower through hole and is connected to the insulating connecting rod, and the upper end of the body of the lower transmission rod 12 is connected to the moving iron core 7.

[0048] To facilitate the fixing of the upper and lower suction units, this electrically controlled permanent magnet bistable operating mechanism further includes a connecting sleeve 6, which is annular and sleeved on the outside of the upper and lower suction units, located between the two suction units. Specifically, mounting ends are formed on the edges of the yokes of both the upper and lower suction units, namely, an upper mounting end and a lower mounting end. Correspondingly, the yoke has a suction part near the center of the mounting end. The height (or height of the suction part itself) protruding towards the moving iron core 7 is higher than the height of the mounting end itself. The upper and lower ends of the connecting sleeve 6 are located between the two mounting ends. The connection method can be a bolt connection or a screw connection 13, such as... Figure 1 Screw 13 is used. The connecting sleeve 6 has a gap between it and the suction part of the yoke in the radial direction. The material of the connecting sleeve is different from that of the yoke, and it can be stainless steel to improve the support strength.

[0049] Another embodiment of the present invention provides a vacuum circuit breaker, comprising: a permanent magnet mechanism and an insulating pull rod. The permanent magnet mechanism is the aforementioned electrically controlled permanent magnet bistable operating mechanism. One end of the insulating pull rod is connected to the permanent magnet mechanism, and the other end is connected to the moving contact of the arc-extinguishing chamber of the vacuum circuit breaker, thereby driving the arc-extinguishing chamber to complete the opening and closing action.

[0050] The closing buffer spring 3 located in the upper suction unit is replaced by the contact pressure spring of the arc-extinguishing chamber of the vacuum circuit breaker. In other words, when the electrically controlled permanent magnet bistable operating mechanism is used in a vacuum circuit breaker, the closing buffer spring 3 is not required, and its function is replaced by the contact pressure spring of the arc-extinguishing chamber of the vacuum circuit breaker.

[0051] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. An electrically controlled permanent magnet bistable operating mechanism, characterized in that, The institutions include: An upper suction unit and a lower suction unit are fixed and arranged opposite to each other. Each suction unit has: a yoke, a permanent magnet, and an excitation coil; the permanent magnet and the excitation coil are both located inside the yoke. A movable iron core is movably disposed between the upper suction unit and the lower suction unit; A transmission rod is mounted on the moving iron core and is driven to move by the moving iron core. One end of the transmission rod passes through the upper suction unit and is connected to the insulating connecting rod. The moving iron core is provided with a first groove on the side facing the upper suction unit. When the circuit is closed, the first groove contains a part of the excitation coil of the upper suction unit. The moving iron core is provided with a second groove on the side facing the lower suction unit. When the circuit is opened, the second groove contains a part of the excitation coil of the lower suction unit. The permanent magnet is sleeved outside the transmission rod and located inside the excitation coil. The end face of the permanent magnet facing the moving iron core is flush with the end face of the yoke facing the moving iron core.

2. The electrically controlled permanent magnet bistable operating mechanism according to claim 1, characterized in that, The organization also includes: A closing buffer spring is located inside the upper suction unit, and one end of the closing buffer spring is connected to the upper suction unit.

3. The electrically controlled permanent magnet bistable operating mechanism according to claim 1 or 2, characterized in that, The other end of the transmission rod passes through the lower suction unit and is connected to a position switch, which is used to characterize the contact position information of the circuit breaker's arc-extinguishing chamber.

4. The electrically controlled permanent magnet bistable operating mechanism according to claim 3, characterized in that, The organization also includes: The tripping buffer spring is located inside the lower suction unit, and one end of the tripping buffer spring is connected to the lower suction unit.

5. The electrically controlled permanent magnet bistable operating mechanism according to claim 3, characterized in that, The transmission rod is divided into an upper transmission rod and a lower transmission rod; The upper transmission rod is disposed on the side of the moving iron core facing the upper suction unit; The lower transmission rod is disposed on the side of the moving iron core facing the lower suction unit, and the other end of the lower transmission rod passes through the lower suction unit.

6. The electrically controlled permanent magnet bistable operating mechanism according to claim 1, characterized in that, The organization also includes: The connecting sleeve is ring-shaped and is fitted onto the outside of the upper suction unit and the lower suction unit.

7. A vacuum circuit breaker, characterized in that, The vacuum circuit breaker includes: The permanent magnet mechanism is the electrically controlled permanent magnet bistable operating mechanism as described in any one of claims 1 to 6 above; An insulating pull rod, one end of which is connected to the permanent magnet mechanism, and the other end of which is connected to the moving contact of the arc-extinguishing chamber of the vacuum circuit breaker.

8. The vacuum circuit breaker according to claim 7, characterized in that, The closing buffer spring located in the upper suction unit of the electrically controlled permanent magnet bistable operating mechanism is replaced by the contact pressure spring of the arc-extinguishing chamber of the vacuum circuit breaker.

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