A bidirectional rotary electromagnetic operating mechanism

Abstract

The present invention provides a bidirectional rotary electromagnetic operating mechanism, which includes an annular moving iron core and a cross-shaped static iron core at the central position of the annular moving iron core; the opening coil of the operating mechanism is wound around the vertical arm of the cross-shaped static iron core, and the closing coil is wound around the horizontal arm of the cross-shaped static iron core; two closing tooth parts of the moving iron core are adjacent to both ends of the horizontal arm of the static iron core, and two opening tooth parts of the moving iron core are adjacent to both ends of the vertical arm of the static iron core; when the opening coil or the closing coil of the static iron core is energized, its magnetic lines of force form two parallel closed magnetic paths along the moving iron core, driving the moving iron core to rotate to perform the opening or closing operation, and the moving iron core keeps the total magnetic resistance between the upper side and the right side of the static iron core and the total magnetic resistance between the lower side and the left side of the static iron core unchanged through the rotating action, so as to avoid the coupling of the magnetic paths between the opening coil and the closing coil; the present invention can flexibly control the opening and closing speeds of the contact system, improve the overall performance of the switch, and improve the mechanical life and electrical life of the switch.

Description

Technical Field

[0001] The present invention relates to the technical field of switching devices, and in particular to a bidirectional rotary electromagnetic operating mechanism. Background Art

[0002] Electromagnetic switches undertake the tasks of flexibly disconnecting and connecting the main circuit in the power system, and their performance indicators directly affect the safety and stability of the entire power system. The operating mechanism is the core component of the electromagnetic switch, and the faults of the electromagnetic switch mainly occur in the operating mechanism. Currently, how to improve the action reliability and breaking capacity of the operating mechanism has become the key technical content of the electromagnetic switch.

[0003] Most of the early designed electromagnetic operating mechanisms are AC mechanisms: when excited by alternating current, their working performance is greatly affected by the phase angle of the exciting voltage. At some phase angles, the electromagnetic switch is difficult to close, while at some phase angles, the suction force is large, which will cause serious contact bounce; during the holding stage, alternating current needs to be continuously applied to the exciting coil, resulting in serious coil temperature rise and increased power consumption. With the emergence of high-performance rare earth permanent magnet materials, permanent magnet operating mechanisms have been gradually applied in switches. Compared with electromagnetic operating mechanisms, permanent magnet mechanisms can maintain the holding state without continuously energizing the coil, and have the advantages of energy saving and no noise, which has attracted wide attention in the switch industry. However, there are still many problems restricting the development of permanent magnet operating mechanisms during operation, such as: the permanent magnet material will demagnetize when working in a high-temperature and strong magnetic field environment.

[0004] The future distribution network has the characteristics of coexistence of AC and DC and multi-point power supply. The dispatching of the distribution network will become more frequent, and the protection will become more diversified. There is an urgent need to develop an operating mechanism with more flexible and perfect control and protection functions to improve the control flexibility and protection diversity of the switch. Summary of the Invention

[0005] The present invention provides a bidirectional rotary electromagnetic operating mechanism, which can flexibly control the opening and closing speeds of the contact system, improve the overall performance of the switch, and increase the mechanical life and electrical life of the switch.

[0006] The present invention adopts the following technical solutions.

[0007] A bidirectional rotary electromagnetic operating mechanism is used for opening and closing operations of an electromagnetic switch. The operating mechanism includes an annular moving iron core and a cross-shaped static iron core at the central position of the annular moving iron core. The opening coil of the operating mechanism is wound around the vertical arm of the cross-shaped static iron core, and the closing coil is wound around the horizontal arm of the cross-shaped static iron core. The two closing tooth parts of the moving iron core are adjacent to the two end parts of the horizontal arm of the static iron core, and the two opening tooth parts of the moving iron core are adjacent to the two end parts of the vertical arm of the static iron core. When the opening coil or the closing coil of the static iron core is energized, its magnetic lines of force form two parallel closed magnetic paths along the moving iron core, driving the moving iron core to rotate to perform opening or closing operations. The moving iron core keeps the total magnetic resistance between the upper side and the right side of the static iron core and the total magnetic resistance between the lower side and the left side of the static iron core unchanged through rotational movement, so as to avoid the coupling of the magnetic paths between the opening coil and the closing coil.

[0008] The moving contact of the electromagnetic switch is arranged at an insulating non-magnetic conducting turntable. The moving contact of the electromagnetic switch is adjacent to the static contact of the electromagnetic switch. The moving iron core is fixedly connected to the insulating non-magnetic conducting turntable. When the moving iron core rotates, it drives the insulating non-magnetic conducting turntable to rotate synchronously, so that the moving contact and the static contact of the electromagnetic switch are engaged or separated.

[0009] When performing a closing operation, the moving iron core rotates counterclockwise. When the closing operation is carried out, the closing coil is energized, and the magnetic lines of force of its magnetic field start from the right closing end of the static iron core around which the closing coil is wound, pass through the closing tooth part and its yoke part on the right side of the moving iron core, then reach the closing tooth part on the left side of the moving iron core, and finally return to the left closing end of the static iron core, forming two parallel closing closed magnetic paths. The closing closed magnetic path generates an electromagnetic force acting on the moving iron core and in the counterclockwise direction F e , reducing the magnetic resistance of the magnetic path and driving the moving iron core to rotate;

[0010] When performing an opening operation, the moving iron core rotates clockwise. When the opening operation is carried out, the opening coil is energized, and the magnetic lines of force of its magnetic field start from the upper opening end of the static iron core around which the opening coil is wound, pass through the opening tooth part and its yoke part on the upper side of the moving iron core, then reach the opening tooth part on the lower side of the moving iron core, and finally return to the lower opening end of the static iron core, forming two parallel opening closed magnetic paths. The opening closed magnetic path generates an electromagnetic force acting on the moving iron core and in the clockwise direction F e , reducing the magnetic resistance of the magnetic path and driving the moving iron core to rotate.

[0011] The electromagnetic switch includes an insulating non-magnetic conducting fixed frame. The insulating non-magnetic conducting fixed frame fixes and limits the insulating non-magnetic conducting turntable with a bolt-shaped part sliding in an arc-shaped limiting groove;

[0012] A torsion spring is arranged in the middle of the insulating non-magnetic conducting fixed frame. When the opening coil and the closing coil are not energized, the torsion spring applies a tangential force to the insulating non-magnetic conducting turntable Ft , maintaining the opening condition of the electromagnetic switch by the annular moving iron core;

[0013] When closing, the electromagnetic force F e is greater than the reaction force of the torsion spring F t , driving the annular moving iron core to rotate counterclockwise, driving the insulating non-magnetic turntable to drive the moving contact to move, and realizing the closing operation;

[0014] When opening, under the cooperation of the torsion force of the torsion spring F t and the electromagnetic force F e , the moving iron core rotates clockwise, the insulating non-magnetic turntable rotates and drives the moving contact to move, and the opening operation is realized.

[0015] During the closing operation, the opening coil and the closing coil are simultaneously energized for excitation to control the combined vector electromagnetic force of the two coils, accurately control the closing speed, and improve the closing performance of the switch;

[0016] When holding the closing position, the closing coil is continuously energized to generate a counterclockwise tangential holding electromagnetic force F e , making the contact reliably held in the closing position; under the closing holding condition, the closing teeth of the annular moving iron core and the closing end of the cross-shaped static iron core are in contact with each other, and the bolt-shaped part moves to the end of the limit groove and is limited by the limit groove.

[0017] During the opening operation, the opening coil and the closing coil are simultaneously energized for excitation to control the combined vector electromagnetic force of the two coils, cooperate with the reaction force of the torsion spring, accurately control the opening speed, improve the opening performance of the switch, and realize the control and protection within the full current range.

[0018] The annular moving iron core is connected to the bolt-shaped parts of the two insulating non-magnetic turntables through arc-shaped limit grooves; the closing coil and the opening coil are respectively wound on the magnetic poles at the four arms of the cross-shaped static iron core, and the static iron core is fixed on the external insulating non-magnetic frame through fasteners;

[0019] The two moving contacts of the electromagnetic switch are fixed at the insulating non-magnetic turntable through brackets; the two static contacts of the electromagnetic switch are fixed to the external insulating non-magnetic frame through brackets, forming a rotating double-break operating mechanism.

[0020] The operating mechanism proposed by the present invention has independent opening and closing magnetic circuits, which can be controlled separately through the opening coil and the closing coil, and its control method is more flexible compared with the traditional single-coil electromagnetic mechanism.

[0021] By controlling the resultant vector electromagnetic force of the closing and opening coils, the present invention can accurately control the closing and opening speeds, adjust the operating characteristics of the operating mechanism, increase the breaking speed during fault opening, reduce the harm of the fault arc to the contacts; during normal closing and opening, reduce the final closing and opening speeds, reduce contact bounce and mechanical shock, improve the electrical and mechanical service lives, and comprehensively improve the control and protection performance of the switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments:

[0023] FIG Figure 1a is a three-dimensional schematic diagram of the operating mechanism of the electromagnetic switch according to the present invention;

[0024] FIG Figure 1b is an exploded schematic diagram of the operating components of the electromagnetic switch according to the present invention;

[0025] FIG Figure 2a is a three-dimensional schematic diagram of the electromagnetic switch according to the present invention;

[0026] FIG Figure 2b is an exploded schematic diagram of the electromagnetic switch according to the present invention;

[0027] FIG Figure 3 is a schematic diagram of the operating mechanism of the electromagnetic switch in the opening holding condition according to the present invention;

[0028] FIG Figure 4 is a schematic diagram of the electromagnetic switch in the closing state according to the present invention;

[0029] FIG Figure 5 is a schematic diagram of the magnetic field line distribution of the electromagnetic switch during the closing process according to the present invention;

[0030] FIG Figure 6 is a schematic diagram of the operating mechanism of the electromagnetic switch in the closing holding condition according to the present invention;

[0031] FIG Figure 7 is a schematic diagram of the magnetic field line distribution of the electromagnetic switch in the closing holding condition according to the present invention;

[0032] FIG Figure 8 is a schematic diagram of the electromagnetic switch in the opening state according to the present invention;

[0033] FIG Figure 9 is a schematic diagram of the magnetic field line distribution of the electromagnetic switch during the opening process according to the present invention;

[0034] In the figures: 1 - fastener; 2 - insulating non-magnetic turntable; 3 - moving iron core; 4 - cross-shaped static iron core; 5 - opening coil; 6 - closing coil; 7 - moving contact; 8 - static contact; 9 - insulating non-magnetic fixed frame; 10 - torsion spring; 11 - arc-shaped limiting groove. Specific Embodiment

[0035] As shown in the figure, a bidirectional rotary electromagnetic actuating mechanism is used for the opening and closing operations of an electromagnetic switch. The actuating mechanism includes an annular moving iron core 3 and a cross-shaped static iron core 4 at the central position of the annular moving iron core. The opening coil 5 of the actuating mechanism is wound around the vertical arm of the cross-shaped static iron core, and the closing coil 6 is wound around the horizontal arm of the cross-shaped static iron core. The two closing tooth parts of the moving iron core are adjacent to the two end parts of the horizontal arm of the static iron core, and the two opening tooth parts of the moving iron core are adjacent to the two end parts of the vertical arm of the static iron core. When the opening coil or the closing coil of the static iron core is energized, its magnetic lines of force form two parallel closed magnetic paths along the moving iron core, driving the moving iron core to rotate to perform the opening or closing operation. The moving iron core keeps the total magnetic resistance between the upper side and the right side of the static iron core and the total magnetic resistance between the lower side and the left side of the static iron core unchanged through the rotational movement, so as to avoid the magnetic path coupling between the opening coil and the closing coil.

[0036] The moving contact 7 of the electromagnetic switch is arranged at the insulating non-magnetic turntable 2. The moving contact of the electromagnetic switch is adjacent to the static contact 8 of the electromagnetic switch. The moving iron core is fixedly connected to the insulating non-magnetic turntable. When the moving iron core rotates, it drives the insulating non-magnetic turntable to rotate synchronously, so that the moving contact and the static contact of the electromagnetic switch are engaged or separated.

[0037] When performing the closing operation, the moving iron core rotates counterclockwise. When the closing coil is energized during the closing operation, the magnetic lines of force of its magnetic field start from the right closing end of the static iron core around which the closing coil is wound, pass through the closing tooth part and its yoke part on the right side of the moving iron core, then to the closing tooth part on the left side of the moving iron core, and finally return to the left closing end of the static iron core, forming two parallel closing closed magnetic paths. The closing closed magnetic path generates an electromagnetic force acting on the moving iron core and in the counterclockwise direction F e , reducing the magnetic resistance of the magnetic path and driving the moving iron core to rotate;

[0038] When performing the opening operation, the moving iron core rotates clockwise. When the opening coil is energized during the opening operation, the magnetic lines of force of its magnetic field start from the upper opening end of the static iron core around which the opening coil is wound, pass through the opening tooth part and its yoke part on the upper side of the moving iron core, then to the opening tooth part on the lower side of the moving iron core, and finally return to the lower opening end of the static iron core, forming two parallel opening closed magnetic paths. The opening closed magnetic path generates an electromagnetic force acting on the moving iron core and in the clockwise direction F e , reducing the magnetic resistance of the magnetic path and driving the moving iron core to rotate.

[0039] The electromagnetic switch includes an insulating non-magnetic fixed frame 9. The insulating non-magnetic fixed frame fixes and limits the insulating non-magnetic turntable with a bolt-shaped part sliding in the arc-shaped limiting groove 11;

[0040] A torsion spring 10 is provided in the middle of the insulating non-magnetic fixing frame; when the opening coil and the closing coil are not energized, the torsion spring applies a tangential force to the insulating non-magnetic turntable F t , so that the annular moving iron core maintains the opening state of the electromagnetic switch;

[0041] When closing, the electromagnetic force F e is greater than the reaction force of the torsion spring F t , so that the annular moving iron core is driven to rotate counterclockwise, driving the insulating non-magnetic turntable to drive the moving contact to move, realizing the closing operation;

[0042] When opening, under the cooperation of the torsion force of the torsion spring F t and the electromagnetic force F e , the moving iron core rotates clockwise, the insulating non-magnetic turntable rotates and drives the moving contact to move, realizing the opening operation.

[0043] During the closing operation, the opening coil and the closing coil are simultaneously energized for excitation to control the combined vector electromagnetic force of the two coils, accurately control the closing speed, and improve the closing performance of the switch;

[0044] When holding the closing position, the closing coil is continuously energized to generate a counterclockwise tangential holding electromagnetic force F e , so that the contact is reliably held in the closing position; under the closing holding condition, the closing tooth part of the annular moving iron core and the closing end part of the cross-shaped static iron core are in contact with each other, and the bolt-shaped part moves to the end of the limit groove and is limited by the limit groove.

[0045] During the opening operation, the opening coil and the closing coil are simultaneously energized for excitation to control the combined vector electromagnetic force of the two coils, cooperate with the reaction force of the torsion spring, accurately control the opening speed, improve the opening performance of the switch, and realize the control and protection within the full current range.

[0046] The annular moving iron core is connected to the bolt-shaped parts of the two insulating non-magnetic turntables through arc-shaped limit grooves; the opening coil and the closing coil are respectively wound around the magnetic poles at the four arms of the cross-shaped static iron core, and the static iron core is fixed on the external insulating non-magnetic frame through fastener 1;

[0047] The two moving contacts of the electromagnetic switch are fixed at the insulating non-magnetic turntable through brackets; the two static contacts of the electromagnetic switch are fixed at the external insulating non-magnetic frame through brackets, forming a rotating double-break operating mechanism.

[0048] In this example, the static iron core is fixed to the external insulating non-magnetic frame by bolts. One end of the torsion spring in the middle of the insulating non-magnetic frame is connected to the bolt for fixing the static iron core on the insulating non-magnetic frame, and the other end is connected to a bolt-shaped part that slides in the arc-shaped limiting groove and is connected to the insulating non-magnetic turntable.

[0049] In this example, when the closing magnetic circuit for opening or the closing magnetic circuit for closing is formed, according to the "reluctance torque" principle, an electromagnetic force acting on the moving iron core will be generated in the magnetic circuit. F e , so that the magnetic reluctance of the entire magnetic circuit can be reduced.

[0050] In this example, during the entire closing operation process, as the moving iron core rotates, the air gaps of the upper and lower opening magnetic circuits and the air gaps of the left and right closing magnetic circuits both increase and decrease. Therefore, the total magnetic reluctances of the upper and right sides and the lower and left sides remain unchanged, and no effective "reluctance torque" is formed, making the opening and closing magnetic circuits independent of each other. There is no coupling between the opening and closing magnetic circuits, making it easier to control the closing force. The opening operation process of this product is the same.

[0051] The arc-shaped limiting groove is located at the insulating non-magnetic fixed frame.

Claims

1. A bidirectional rotary electromagnetic operating mechanism for opening and closing operations of an electromagnetic switch, characterized in that: The operating mechanism includes an annular moving iron core and a cross-shaped static iron core at the central position of the annular moving iron core; the opening coil of the operating mechanism is wound around the vertical arm of the cross-shaped static iron core, and the closing coil is wound around the horizontal arm of the cross-shaped static iron core; the two closing tooth parts of the moving iron core are adjacent to the two end parts of the horizontal arm of the static iron core, and the two opening tooth parts of the moving iron core are adjacent to the two end parts of the vertical arm of the static iron core; when the opening coil or the closing coil of the static iron core is energized, its magnetic lines of force form two parallel closed magnetic paths along the moving iron core, driving the moving iron core to rotate to perform the opening or closing operation. The moving iron core keeps the total magnetic resistance between the upper side and the right side of the static iron core and the total magnetic resistance between the lower side and the left side of the static iron core unchanged through the rotation action, so as to avoid the magnetic circuit coupling between the opening coil and the closing coil. The electromagnetic switch includes an insulating non-magnetic fixed frame, and the insulating non-magnetic fixed frame fixes and limits the insulating non-magnetic turntable with a bolt-shaped part sliding in an arc-shaped limiting groove. A torsion spring is provided in the middle of the insulating non-magnetic fixed frame; when the opening coil and the closing coil are not energized, the torsion spring applies a tangential force to the insulating non-magnetic turntable F t , so that the annular moving iron core maintains the opening condition of the electromagnetic switch; When closing, the electromagnetic force F e is greater than the reaction force of the torsion spring F t , causing the annular moving iron core to be driven and rotate counterclockwise, driving the insulating non-magnetic turntable to drive the moving contact to move, and realizing the closing operation; When opening the switch, under the cooperation of the torsion force of the torsion spring F t and the electromagnetic force F e the moving iron core rotates clockwise, the insulating non-magnetic turntable rotates and drives the moving contact to move, realizing the opening operation; During the closing operation, the opening coil and the closing coil are energized simultaneously for excitation to control the combined vector electromagnetic force of the two groups of coils, accurately control the closing speed, and improve the closing performance of the switch. When the closing is held, the closing coil is continuously energized to generate a counterclockwise tangential holding electromagnetic force F e , so that the contact is reliably held in the closed position; in the closing holding condition, the closing tooth part of the annular moving iron core and the closing end part of the cross-shaped static iron core are in contact with each other, and the bolt-shaped part moves to the end of the limit groove and is limited by the limit groove; During the opening operation, the opening coil and the closing coil are energized simultaneously for excitation to control the combined vector electromagnetic force of the two groups of coils, cooperate with the reaction force of the torsion spring, accurately control the opening speed, improve the opening performance of the switch, and achieve control and protection within the full current range.

2. The bi-directional rotary electromagnetic operating mechanism according to claim 1, wherein: The moving contact of the electromagnetic switch is arranged at the insulating non-magnetic turntable; the moving contact of the electromagnetic switch is adjacent to the static contact of the electromagnetic switch. The moving iron core is fixedly connected to the insulating non-magnetic turntable. When the moving iron core rotates, it drives the insulating non-magnetic turntable to rotate synchronously, so that the moving contact and the static contact of the electromagnetic switch are engaged or separated.

3. The bidirectional rotary electromagnetic operating mechanism according to claim 2, characterized in that: When a closing operation is performed, the moving iron core rotates counterclockwise; during the closing operation, the closing coil is energized, and the magnetic force lines of its magnetic field start from the right closing end of the static iron core around which the closing coil is wound, pass through the closing tooth part and its yoke part on the right side of the moving iron core, then reach the closing tooth part on the left side of the moving iron core, and finally return to the left closing end of the static iron core, forming two parallel closing closed magnetic paths; the closing closed magnetic paths generate an electromagnetic force acting on the moving iron core and in the counterclockwise direction F e , reducing the magnetic resistance of the magnetic path and driving the moving iron core to rotate; When a tripping operation is performed, the moving iron core rotates clockwise; during the tripping operation, the tripping coil is energized, and the magnetic force lines of its magnetic field start from the upper tripping end of the static iron core around which the tripping coil is wound, pass through the tripping tooth part and its yoke part on the upper side of the moving iron core, then reach the tripping tooth part on the lower side of the moving iron core, and finally return to the lower tripping end of the static iron core, forming two parallel tripping closed magnetic circuits; the tripping closed magnetic circuits generate an electromagnetic force acting on the moving iron core and in the clockwise direction F e , reducing the magnetic resistance of the magnetic circuit and driving the rotation of the moving iron core.

4. A bidirectional rotary electromagnetic operating mechanism according to claim 1, characterized in that: The annular moving iron core is connected to the bolt-shaped parts of the two insulating non-magnetic turntables through arc-shaped limiting grooves; the opening coils and the closing coils are respectively wound around the magnetic poles at the four arms of the cross-shaped static iron core, and the static iron core is fixed on the external insulating non-magnetic frame through fasteners. The two moving contacts of the electromagnetic switch are fixed at the insulating non-magnetic turntable through brackets; the two static contacts of the electromagnetic switch are fixed at the external insulating non-magnetic frame through brackets, forming a rotating double-break operating mechanism.

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