Permanent magnet operating mechanism and circuit breaker

Abstract

The permanent magnet operating mechanism specifically comprises a bottom plate, a static iron core, an annular permanent magnet and an outer iron core, wherein the static iron core, the annular permanent magnet and the outer iron core are sequentially arranged from inside to outside; an over-travel spring is arranged in a first placement cavity in the static iron core, and one end of the over-travel spring is fixed in the first placement cavity; the static iron core is sleeved with an operation coil. Comprising an outer circle part and an inner circle part and is arranged above the outer iron core and the static iron core; a second placing cavity is formed in the inner circle part; a first spring groove and a second spring groove are formed in the second placement cavity, and an opening spring is arranged in the first spring groove; the opening spring passes through the over-travel spring, and the other end of the over-travel spring is fixed in the second spring groove. According to the technical scheme, the permanent magnet operating mechanism adopts a monostable permanent magnet mechanism design principle, mechanical loss of the circuit breaker during opening or closing is avoided, and the mechanical life of the circuit breaker operating mechanism is prolonged.

Description

Technical Field

[0001] This invention relates to, but is not limited to, the field of vacuum circuit breakers, and particularly to a permanent magnet operating mechanism and a circuit breaker. Background Technology

[0002] The operating mechanism of the circuit breaker in the 10kV gas-insulated switchgear generally adopts the spring operating mechanism. The spring operating mechanism consists of more than 200 parts. The parts are complicated to process, the process requirements are high, the transmission structure is complex, and the failure rate is relatively high. According to data, 70% of the failures of power switchgear are caused by mechanical failures of the spring operating mechanism. Under the development trend of long life and maintenance-free, it is increasingly unable to meet the needs of maintenance-free and intelligent power grid construction. Summary of the Invention

[0003] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0004] This invention provides a permanent magnet operating mechanism that can improve the mechanical life of circuit breakers.

[0005] In a first aspect, embodiments of the present invention provide a permanent magnet operating mechanism, comprising:

[0006] A base plate, wherein a stationary iron core, an annular permanent magnet, and an outer iron core are sequentially arranged from the inside out; the stationary iron core includes a boss-shaped outer wall, the outer wall including an upper boss and a lower boss, and the annular permanent magnet is disposed between the lower boss and the outer iron core; a first placement cavity is provided inside the stationary iron core, and an overtravel spring is provided inside the first placement cavity, the first end of the overtravel spring being fixed inside the first placement cavity;

[0007] An operating coil is sleeved on the upper protrusion; the operating coil is electrically connected to a power source.

[0008] A moving iron core is disposed above the outer iron core and the stationary iron core. The moving iron core includes an outer circular portion and an inner circular portion. The lower surface of the outer circular portion coincides with the upper surface of the outer iron core, and the lower surface of the inner circular portion coincides with the upper surface of the upper boss. A second placement cavity is provided on the side of the inner circular portion near the stationary iron core. The second placement cavity includes a first spring groove and a second spring groove. A tripping spring is disposed in the first spring groove. The tripping spring passes through the overtravel spring, and the second end of the overtravel spring is fixed in the second spring groove. A third placement cavity is provided between the inner circular portion and the outer circular portion, and the third placement cavity covers the operating coil.

[0009] The top plate is mounted on the moving iron core.

[0010] The permanent magnet operating mechanism according to the first aspect of the present invention has at least the following beneficial effects: In the permanent magnet operating mechanism provided by the present invention, the opening spring and the overtravel spring are both built into the moving and stationary iron cores. When closing, the operating coil is energized with a positive DC current, driving the moving iron core to move towards the stationary iron core, while simultaneously compressing the opening spring and the overtravel spring to store energy. After successful closing, the stationary iron core and the inner circular end face of the moving iron core attract each other, and the outer iron core and the outer circular end face of the moving iron core attract each other, forming a closed magnetic circuit, providing the operating mechanism with the closing holding force. When opening, a reverse DC current is energized to the operating coil to demagnetize the iron core. When the closing holding force is insufficient to resist the combined force of the opening spring and the overtravel spring, the iron core begins to move upward under the spring thrust, realizing the opening of the mechanism. According to the technical solution of the present invention, the permanent magnet operating mechanism adopts the design principle of a monostable permanent magnet mechanism, avoiding mechanical losses of the circuit breaker during opening or closing, and improving the mechanical life of the circuit breaker operating mechanism.

[0011] According to some embodiments of the first aspect of the present invention, the permanent magnet operating mechanism further includes a drive plate disposed on the top plate; drive ear plates are disposed on both sides of the drive plate, and each drive ear plate is provided with a manual drive hole for mounting a manual drive shaft.

[0012] According to some embodiments of the first aspect of the present invention, a first through hole is provided at the bottom of the first placement cavity, a second through hole is also provided on the upper surface of the inner circle, and a third through hole is provided at the bottom of the drive plate; the centers of the first through hole, the second through hole and the third through hole coincide.

[0013] According to some embodiments of the first aspect of the present invention, a guide sleeve is further provided between the bottom of the stationary iron core and the base plate, and a first protrusion hole is provided at the center of the guide sleeve, the first protrusion hole passing through the first through hole.

[0014] According to some embodiments of the first aspect of the present invention, a plurality of first limiting holes are provided on the base plate, and a plurality of second limiting holes are provided on the top plate; a plurality of vertically arranged limiting rods are provided between the base plate and the top plate, one end of each limiting rod is fixed in a first limiting hole, and the other end of each limiting rod is fixed in a second limiting hole.

[0015] According to some embodiments of the first aspect of the present invention, the operating coil includes a cylindrical frame and a winding assembly, the inner side of the cylindrical frame is provided with a fixing thread, and the cylindrical frame is sleeved on the upper boss of the stationary iron core through the fixing thread; the winding assembly is wound on the cylindrical frame.

[0016] According to some embodiments of the first aspect of the present invention, the permanent magnet operating mechanism further includes a protective sleeve, the protective sleeve being sleeved on the outer circumference of the moving iron core and the outer side of the outer iron core.

[0017] Secondly, embodiments of the present invention provide a circuit breaker including the permanent magnet operating mechanism described in the above-mentioned embodiments.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0019] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0020] Figure 1 This is one of the front sectional views of a permanent magnet operating mechanism provided in an embodiment of the present invention;

[0021] Figure 2 This is a second front sectional view of a permanent magnet operating mechanism provided in another embodiment of the present invention;

[0022] Figure 3 This is a side view of a permanent magnet operating mechanism provided in another embodiment of the present invention.

[0023] Explanation of reference numerals in the attached drawings: 1. Base plate; 2. Static iron core; 2. Upper boss 201; 2. Lower boss 202; 2. First placement cavity 203; 3. Outer iron core; 4. Permanent magnet; 5. Operating coil; 6. Moving iron core; 6. Outer circle 601; Inner circle 602; 6. Second placement cavity 6021; 7. Opening spring; 8. Overtravel spring; 9. Guide sleeve; 9. First protrusion hole 901; 10. Limiting rod; 11. Top plate; 12. Drive plate; 12. Manual opening drive hole 1201; 13. Protective sleeve. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0025] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0026] In the description of this invention, the use of "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0027] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0028] It should be noted that the embodiments of this application do not limit any improvement of the method, and the functions that the device or apparatus can achieve are only based on the hardware architecture of the device or apparatus itself.

[0029] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0030] Reference Figures 1-3 In a first aspect, embodiments of the present invention provide a permanent magnet operating mechanism, comprising: a base plate 1, wherein a stationary iron core 2, an annular permanent magnet 4, and an outer iron core 3 are sequentially arranged in a direction from the inside out; the stationary iron core 2 is provided with a boss-shaped outer wall, the outer wall including an upper boss 201 and a lower boss 202, and the annular permanent magnet 4 is disposed between the lower boss 202 and the outer iron core 3; a first placement cavity 203 is provided inside the stationary iron core 2, and an overtravel spring 8 is provided inside the first placement cavity 203, the first end of the overtravel spring 8 being fixed inside the first placement cavity 203; an operating coil 5, sleeved on the upper boss 201; the operating coil 5 being electrically connected to a power source; and a moving iron core 6, disposed between the outer iron core 3 and the stationary iron core. Above 2, the moving iron core 6 includes an outer circular portion 601 and an inner circular portion 602; the lower surface of the outer circular portion 601 coincides with the upper surface of the outer iron core 3, and the lower surface of the inner circular portion 602 coincides with the upper surface of the upper boss 201; a second placement cavity 6021 is provided on the side of the inner circular portion 602 near the stationary iron core 2; the second placement cavity 6021 includes a first spring groove and a second spring groove, and a tripping spring 7 is provided in the first spring groove; the tripping spring 7 passes through the overtravel spring 8, and the second end of the overtravel spring 8 is fixed in the second spring groove; a third placement cavity is provided between the inner circular portion 602 and the outer circular portion 601, and the third placement cavity is covered on the operating coil 5; the top plate 11 is provided on the moving iron core 6.

[0031] Specifically, in this embodiment of the invention, the base plate 1 is used to support the permanent magnet operating mechanism. It is made of non-magnetic sheet metal and has a stationary iron core 2, an operating coil 5, and an outer iron core 3 evenly distributed from the inside to the outside. The stationary iron core 2 is mounted on the base plate 1 through screw holes. In the permanent magnet operating mechanism, the stationary iron core 2 combines the magnetic field characteristics of the permanent magnet 4 and the magnetic field generated by the operating coil 5. In this embodiment of the invention, the stationary iron core 2 is made of magnetic material, which can be ferrite or silicon steel sheet. The stationary iron core 2 is cylindrical in shape and has a boss-shaped outer wall. The lower boss 202 of the stationary iron core 2 can fit with the annular permanent magnet 4 to form a closed magnetic circuit, and the upper boss 201 of the stationary iron core 2 can fit with the operating coil 5 to stabilize the position of the operating coil 5. The permanent magnet 4 generates a stable magnetic field to magnetize the stationary iron core 2 and provides a stable and continuous magnetic force to maintain the position of the moving iron core 6 during closing, reducing coil energy consumption. A hollow first placement cavity 203 is located at the center of the stationary iron core 2, which houses the overtravel spring 8. The overtravel spring 8 controls the closing and opening operations of the permanent magnet operating mechanism, ensuring that the operating mechanism can stop stably when reaching its limit position, reducing impact and wear. The outer iron core 3 is also mounted on the base plate 1 through screw holes. Its material and function are the same as the stationary iron core 2, forming a closed magnetic circuit to attract the moving iron core 6 together with the stationary iron core 2. The operating coil 5 is connected to the power supply. When the operating coil 5 is energized, the direction of the magnetic force it generates is affected by the direction of the current, thus realizing the closing and opening of the circuit between the moving iron core 6 and the stationary iron core 2. The moving iron core 6 is cylindrical in shape, with its bottom divided into an inner circle and an outer circle. The outer circle 601 has the same dimensions as the end face of the outer iron core 3, and the inner circle 602 has the same dimensions as the end face of the boss 201 on the stationary iron core 2, to ensure that the closing force is strong enough. The center of the inner circle 602 is provided with a first spring groove and a second spring groove. The first spring groove is used to install the opening spring 7, and the second spring groove is used to fix the overtravel spring 8 at one end of the moving iron core 6, to ensure that the position of the spring is restricted. The width of the second spring groove is slightly wider than that of the first spring groove. That is, the width of the first spring groove matches the opening spring 7, and the width of the second spring groove matches the width of the overtravel spring 8, to prevent the overtravel spring 8 and the opening spring 7 from affecting each other. The tripping spring 7 is used to realize the rapid tripping of the circuit breaker. When the circuit breaker needs to quickly disconnect the circuit, the tripping spring 7 releases the stored energy and pushes the moving iron core 6 to quickly separate from the stationary iron core 2. The tripping spring 7 is installed inside the overtravel spring 8. This arrangement can ensure that the two springs will not affect each other. The moving iron core 6 is also provided with a third placement cavity for accommodating and limiting the operation coil 5. Finally, the top of the moving iron core 6 is also covered with a top plate 11.

[0032] It should be noted that, according to the embodiments described above, the opening spring 7 and the overtravel spring 8 are both built into the moving and stationary iron cores 2. During closing, a positive DC current is applied to the operating coil 5, driving the moving iron core 6 to move towards the stationary iron core 2. Simultaneously, the opening spring 7 and the overtravel spring 8 are compressed to store energy. After successful closing, the stationary iron core 2 and the end face of the inner circle 602 of the moving iron core 6 attract each other, and the outer iron core 3 and the end face of the outer circle 601 of the moving iron core 6 attract each other, forming a closed magnetic circuit, providing the holding force for the permanent magnet operating mechanism. During opening, a reverse DC current is applied to the operating coil 5 to demagnetize the stationary iron core 2 and the outer iron core 3. When the holding force is insufficient to resist the combined force of the opening spring 7 and the overtravel spring 8, the moving iron core 6 begins to move upward under the thrust of the two springs, realizing the opening of the permanent magnet operating mechanism. Furthermore, the specific stroke of the moving iron core 6 during the opening process depends on the pre-compression force of the opening spring 7.

[0033] Reference Figures 1-3 According to some embodiments of the present invention, the permanent magnet operating mechanism further includes a drive plate 12, which is disposed on the top plate 11; drive ear plates are provided on both sides of the drive plate 12, and each drive ear plate is provided with a manual drive hole 1201 for mounting a manual drive shaft.

[0034] Specifically, the drive plate 12 is fixed on the top plate 11. The drive ear plates at both ends of the drive plate 12 are made of non-magnetic material by sheet metal. The drive ear plates on both sides are provided with manual opening drive holes 1201. When the mechanism is closed, a manual opening shaft can be set, and the emergency manual opening function of the permanent magnet operating mechanism can be realized through the manual opening drive holes 1201.

[0035] According to some embodiments of the present invention, a first through hole is provided at the bottom of the first placement cavity 203, a second through hole is provided on the upper surface of the inner circle 602, and a third through hole is provided at the bottom of the drive plate 12; the centers of the first through hole, the second through hole and the third through hole coincide.

[0036] Specifically, during the circuit breaker's tripping process, a pull rod penetrating the permanent magnet operating mechanism is required. This ensures that when the permanent magnet operating mechanism trips, it can trigger other mechanical components of the circuit breaker to perform corresponding actions. Therefore, the first, second, and third vias are through holes provided by the permanent magnet operating mechanism for installing the pull rod. Furthermore, the coincidence of the centers of the first, second, and third vias helps limit the relative position of the permanent magnet operating mechanism and the circuit breaker's pull rod, making the circuit breaker's structure more stable.

[0037] According to some embodiments of the present invention, a guide sleeve 9 is also provided between the bottom of the stationary iron core 2 and the base plate 1, and a first protrusion hole 901 is provided at the center of the guide sleeve 9, and the first protrusion hole 901 passes through the first through hole.

[0038] Specifically, the guide sleeve 9 is cylindrical, and the protruding portion of the first convex hole 901 in the middle of the guide sleeve 9 passes through the first through hole in the above-described embodiment and is embedded in the first placement cavity 203. The guide sleeve 9 has a self-lubricating function, which can reduce the friction when the pull rod is used for transmission operation.

[0039] According to some embodiments of the present invention, a plurality of first limiting holes are provided on the bottom plate 1, and a plurality of second limiting holes are provided on the top plate 11; a plurality of vertically arranged limiting rods 10 are provided between the bottom plate 1 and the top plate 11, one end of each limiting rod 10 is fixed in a first limiting hole, and the other end of each limiting rod 10 is fixed in a second limiting hole.

[0040] Specifically, the top plate 11 and the bottom plate 1 are provided with limiting holes for installing the limiting rod 10 at the four corners. The limiting rod 10 is cylindrical and has an installation through hole inside. Its height matches the height of the stationary iron core 2 and the moving iron core 6. When the limiting rod 10 is fixed between the bottom plate 1 and the top plate 11, it can jointly ensure the movement stroke of the operating mechanism.

[0041] According to some embodiments of the present invention, the operating coil 5 includes a cylindrical frame and a winding assembly. The inner side of the cylindrical frame is provided with a fixing thread, and the cylindrical frame is sleeved on the upper boss 201 of the stationary iron core 2 through the fixing thread; the winding assembly is wound on the cylindrical frame.

[0042] Specifically, the operating coil 5 consists of a cylindrical frame and a winding assembly. The lower part of the cylindrical frame is provided with a limiting boss, and the inner side of the limiting boss is provided with a fixing thread. The limiting boss is threadedly connected to the stationary iron core 2 through the fixing thread.

[0043] According to some embodiments of the present invention, the permanent magnet operating mechanism further includes a protective sleeve 13, which is sleeved on the outer circle 601 of the moving iron core 6 and the outer side of the outer iron core 3.

[0044] Specifically, the protective sleeve 13 is cylindrical and can be fitted onto the outer circle of the outer iron core 3 and the moving iron core 6. It can prevent dust from entering during the opening and closing of the permanent magnet operating mechanism and ensure the cleanliness of its contact surface.

[0045] Secondly, embodiments of the present invention provide a circuit breaker including the permanent magnet operating mechanism described in the above-mentioned embodiments.

[0046] It should be noted that by replacing the spring-operated operating mechanism in the circuit breaker with a permanent magnet operating mechanism, when closing, a positive DC current is supplied to the operating coil 5, driving the moving iron core 6 to move towards the stationary iron core 2. At the same time, the opening spring 7 and the overtravel spring 8 are compressed to store energy. After successful closing, the stationary iron core 2 and the end face of the inner circle 602 of the moving iron core 6 are attracted, and the outer iron core 3 and the end face of the outer circle 601 of the moving iron core 6 are attracted, forming a closed magnetic circuit, which provides the closing holding force for the permanent magnet operating mechanism. When opening, a reverse DC current is supplied to the operating coil 5 to demagnetize the iron core. When the closing holding force is insufficient to resist the combined force of the opening spring 7 and the overtravel spring 8, the moving iron core 6 begins to move upward under the influence of the two spring thrusts, realizing the opening of the permanent magnet operating mechanism. Compared with the spring-operated mechanical mechanism of the circuit breaker, this can improve the mechanical life of the circuit breaker and make the circuit breaker more stable and reliable.

[0047] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

Claims

1. A permanent magnet operating mechanism, characterized in that, include: A base plate, wherein a stationary iron core, an annular permanent magnet, and an outer iron core are sequentially arranged from the inside out; the stationary iron core includes a boss-shaped outer wall, the outer wall including an upper boss and a lower boss, and the annular permanent magnet is disposed between the lower boss and the outer iron core; a first placement cavity is provided inside the stationary iron core, and an overtravel spring is provided inside the first placement cavity, the first end of the overtravel spring being fixed inside the first placement cavity; An operating coil is sleeved on the upper protrusion; the operating coil is electrically connected to a power source. A moving iron core is disposed above the outer iron core and the stationary iron core. The moving iron core includes an outer circular portion and an inner circular portion. The lower surface of the outer circular portion coincides with the upper surface of the outer iron core, and the lower surface of the inner circular portion coincides with the upper surface of the upper boss. A second placement cavity is provided on the side of the inner circular portion near the stationary iron core. The second placement cavity includes a first spring groove and a second spring groove. A tripping spring is disposed in the first spring groove. The tripping spring passes through the overtravel spring, and the second end of the overtravel spring is fixed in the second spring groove. A third placement cavity is provided between the inner circular portion and the outer circular portion, and the third placement cavity covers the operating coil. The top plate is mounted on the moving iron core.

2. The permanent magnet operating mechanism according to claim 1, characterized in that, The permanent magnet operating mechanism also includes a drive plate, which is disposed on the top plate; drive ear plates are provided on both sides of the drive plate, and each drive ear plate is provided with a manual drive hole for installing a manual drive shaft.

3. The permanent magnet operating mechanism according to claim 2, characterized in that, The bottom of the first placement cavity is provided with a first through hole, the upper surface of the inner circle is also provided with a second through hole, and the bottom of the drive plate is provided with a third through hole; the centers of the first through hole, the second through hole and the third through hole coincide.

4. The permanent magnet operating mechanism according to claim 3, characterized in that, A guide sleeve is provided between the bottom of the stationary iron core and the base plate. A first protruding hole is provided at the center of the guide sleeve, and the first protruding hole passes through the first through hole.

5. The permanent magnet operating mechanism according to claim 1, characterized in that, The base plate is provided with a plurality of first limiting holes, and the top plate is provided with a plurality of second limiting holes; a plurality of vertically arranged limiting rods are provided between the base plate and the top plate, one end of each limiting rod is fixed in a first limiting hole, and the other end of each limiting rod is fixed in a second limiting hole.

6. The permanent magnet operating mechanism according to claim 1, characterized in that, The operating coil includes a cylindrical frame and a winding assembly. The inner side of the cylindrical frame is provided with a fixing thread, and the cylindrical frame is sleeved on the upper boss of the stationary iron core through the fixing thread. The winding assembly is wound on the cylindrical frame.

7. The permanent magnet operating mechanism according to claim 1, characterized in that, The permanent magnet operating mechanism also includes a protective sleeve, which is fitted onto the outer circumference of the moving iron core and the outer side of the outer iron core.

8. A circuit breaker, characterized in that, Includes the permanent magnet operating mechanism as described in any one of claims 1 to 7.

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