CN210073746U - Lightweight compact electromagnetic repulsion mechanism - Google Patents
Lightweight compact electromagnetic repulsion mechanism Download PDFInfo
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- CN210073746U CN210073746U CN201920874603.2U CN201920874603U CN210073746U CN 210073746 U CN210073746 U CN 210073746U CN 201920874603 U CN201920874603 U CN 201920874603U CN 210073746 U CN210073746 U CN 210073746U
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Abstract
The utility model relates to a lightweight compact electromagnetic repulsion mechanism, belonging to the field of a quick mechanical switch operating mechanism, wherein the electromagnetic repulsion mechanism comprises a driving device, a retaining device and a buffer device; the driving device comprises a switching-off coil, a switching-on coil and a repulsion plate and is used for providing driving force when the operating mechanism is switched on and off, and the retaining device comprises a spring, a piston, a spring base, a shell, a connecting plate and a bolt and is used for providing retaining force of the mechanism at the switching-on and off position and is hinged with the repulsion plate through the connecting plate. The utility model provides an electromagnetic repulsion mechanism closely combines holding device, buffer with drive arrangement, compares the electromagnetic repulsion mechanism of general design, has not only reduced moving part's total quality, is guaranteeing simultaneously to keep, under the prerequisite of shock-absorbing capacity, has effectively improved the drive efficiency and the maintainability of electromagnetic repulsion mechanism, has reduced the volume and the cost of product.
Description
Technical Field
The utility model belongs to quick mechanical switch operating mechanism field, more specifically relates to a lightweight compact electromagnetism repulsion mechanism.
Background
The development of a circuit breaker capable of rapidly cutting off fault current is a key for promoting the technical development and application of a high-voltage direct-current power grid. According to different topological principles, dc circuit breakers can be classified into three types, namely mechanical dc circuit breakers, solid-state dc circuit breakers and hybrid dc circuit breakers. Solid-state direct current circuit breakers require a large number of power electronic devices to be connected in series and in parallel, high through-current loss is caused, and the current schemes suitable for high-voltage direct current power grids are mainly mechanical and hybrid.
The quick mechanical switch is a key component in the two, and the action speed of the quick mechanical switch directly determines the breaking performance of the high-voltage direct-current circuit breaker. The operation mechanism commonly used in the fast mechanical switch at present is an electromagnetic repulsion mechanism based on the eddy repulsion driving principle.
Compared with the traditional operating mechanism, the electromagnetic repulsion mechanism has the advantages of short response time, high rigid-separation speed, simple structure and the like. However, the retaining device in the existing electromagnetic repulsion mechanism generally adopts a permanent magnet or disc spring mechanism, and once the retaining device is designed and formed, the output characteristic of the retaining device cannot be adjusted; the design of the existing retaining device requires that a driving device, the retaining device and a buffer device are independently arranged and are sequentially connected to a transmission rod, so that the occupied area and the height of a product are larger than those of the traditional mechanism, and the requirement of compacting electrical equipment cannot be met; the existing mechanism has too many additional parts and large moving mass, so that the driving efficiency of the electromagnetic repulsion mechanism during opening and closing operations is very low.
SUMMERY OF THE UTILITY MODEL
To the above defect or the improvement demand of prior art, the utility model aims at providing a lightweight compact electromagnetism repulsion mechanism aims at solving current electromagnetism repulsion mechanism retaining device's the unadjustable problem of branch, combined floodgate holding power.
In order to achieve the above object, the present invention provides a light-weight compact electromagnetic repulsion mechanism, which comprises a driving device, a buffering device and a retaining device; the driving device comprises a brake separating coil, a brake closing coil and a repulsion disc; the opening coil and the closing coil are oppositely arranged, and the upper end of the repulsion plate penetrates through the through hole of the opening coil; the buffer device is arranged opposite to the repulsion disc, and the upper part of the buffer device passes through the through hole of the closing coil; the retaining device is connected with the repulsion plate, and during work, the adjustment of the retaining force is realized by adjusting the rigidity of a spring in the retaining device, the screwing depth of a bolt or the length of the connecting plate.
The utility model discloses in owing to designed a retaining device based on coil spring for all be in compression state at the separating brake position of mechanism and closing position spring, can adjust the holding power size through the length of the precession degree of depth of the rigidity of adjustment spring, bolt or connecting plate. Specifically, the stiffness of the spring determines the output force of the spring under a certain given compression amount, and the greater the stiffness is, the greater the opening and closing holding force of the holding device under the same spring compression amount is; the screw-in depth of the bolt determines the compression amount of the spring, and the larger the screw-in depth is, the larger the force of the spring is, the larger the opening and closing holding force is; the length of the connecting plate determines the size of an included angle between the connecting plate and the horizontal direction when the holding device is at the opening and closing positions, the longer the connecting plate is, the smaller the included angle is, and the smaller the holding device exerts force.
Furthermore, the electromagnetic repulsion mechanism comprises two holding devices, wherein the two holding devices are connected with the repulsion plate and are arranged in an axial symmetry mode around the repulsion plate. The connecting plate of the retaining device is connected with the repulsion plate, so that the retaining device is installed on two sides of the driving device, and the buffer device penetrates through the through hole in the closing coil and directly acts on the bottom of the repulsion plate, thereby greatly reducing the axial height of the mechanism, being beneficial to the miniaturization design of an operating mechanism box and ensuring that the whole mechanism has small volume and small motion quality.
Still further, the holding device includes: the device comprises a connecting plate, a piston, a spring base, a bolt and a shell; the shell is internally of a cylindrical cavity structure, and the piston, the spring and the spring base are all arranged in the cylindrical cavity; the spring is arranged between the piston and the spring base, one end of the connecting plate is connected with the piston, and the other end of the connecting plate is connected with the repulsion plate.
Furthermore, the inner diameter of the shell is in clearance fit with the outer diameters of the piston and the spring base, and the piston and the spring base can slide in the shell. Specifically, the lubricating oil is added in the shell for lubrication, so that the friction force generated during the movement of the piston is reduced, the blockage is avoided, and the opening and closing operation of the electromagnetic repulsion mechanism can be smoothly carried out.
Furthermore, through holes are formed in the piston, the repulsion plate and the two ends of the connecting plate, one end of the connecting plate is connected with the piston through the through holes, and the other end of the connecting plate is connected with the repulsion plate through the through holes.
Further, the connecting plate and the piston, and the connecting plate and the repulsive force plate are hinged by pins or bearings. The hinge connection structure is simpler by adopting pin connection; the friction force of the hinge connection is smaller by adopting the bearing connection, the abrasion of the holding device when the mechanism is operated is reduced, and the output force of the mechanism when the mechanism is operated is reduced, so that the power supply volume and the cost are reduced.
Furthermore, a threaded hole is formed in the shell, and the bolt penetrates through the threaded hole of the shell to be in contact with the spring base. The compression amount of the spring can be adjusted by adjusting the position of the bolt, and the opening and closing holding force of the mechanism is further adjusted.
Furthermore, the repulsion plate, the connecting plate, the piston, the spring base, the bolt and the shell are all made of superhard aluminum alloy. Compared with carbon steel and other alloy steel materials, the superhard aluminum alloy has lower density and higher structural strength, so that the moving part of the mechanism has lower mass, and the power supply volume and the cost are reduced.
Further, the buffer device is a hydraulic buffer, a spring buffer or a polyurethane material buffer. When hydraulic buffering is adopted, the impact of the hydraulic buffering on the mechanism is smaller, and the mechanical life of the mechanism can be prolonged.
Furthermore, the outer diameters of the opening coil, the closing coil and the repulsion disc are the same. The electromagnetic repulsion force generated between the repulsion plate and the coil is the largest when the sizes of the repulsion plate and the coil are the same, and the driving efficiency of the electromagnetic repulsion mechanism obtains the optimal value, so that the outer diameter of the repulsion plate is the same as that of the opening and closing coil.
Compared with the prior art, the utility model, owing to designed a new keeper structure to following technological effect has been produced:
(1) the utility model discloses in, the holding device based on coil spring all is in compression state at the separating brake position of mechanism and closing position spring, can adjust the holding power size through the length of the precession degree of depth of adjustment spring's rigidity, bolt or connecting plate.
(2) The utility model discloses carry out hinged joint with holding device's connecting plate and repulsion dish, make holding device install to the drive arrangement both sides, pass the inside through-hole of combined floodgate coil and direct action in repulsion dish bottom with buffer simultaneously to greatly reduced the axial height of mechanism, be favorable to the miniaturized design of operating mechanism case.
(3) The utility model discloses saved the design and the assembly of other additional spare parts such as transmission connecting rod, holding device mount pad, alleviateed the moving part quality greatly, made the mechanism obviously reduce in branch, combined floodgate operation power to reduce power capacity under the same drive requirement, effectively promoted the drive efficiency of mechanism, reduced the cost and the volume of product.
Drawings
Fig. 1 is a schematic view of a lightweight compact electromagnetic repulsion mechanism provided in an embodiment of the present invention;
fig. 2 is a schematic view of a holding device according to an embodiment of the present invention.
The figures are numbered: 1-driving device, 2-buffering device, 3-holding device, 11-opening coil, 12-closing coil, 13-repulsion plate, 31-connecting plate, 32-piston, 33-spring, 34-spring base, 35-bolt and 36-shell.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The utility model combines the holding device, the buffer device and the driving device tightly, and has the advantages of light weight and compactness; meanwhile, the spring is in a compressed state at the opening position and the closing position of the mechanism based on the retaining device of the spiral spring, and the size of the retaining force can be adjusted by adjusting the rigidity of the spring, the screwing depth of the bolt or the length of the connecting plate. Additionally, the utility model discloses saved the design and the assembly of other additional spare parts such as transmission connecting rod, holding device mount pad, alleviateed the moving part quality greatly, made the mechanism obviously reduce in branch, combined floodgate operation power to reduce power capacity under the same drive requirement, effectively promoted the drive efficiency of mechanism, reduced the cost and the volume of product.
Fig. 1 shows a schematic view of a lightweight compact electromagnetic repulsion mechanism provided by an embodiment of the present invention, and fig. 2 shows a schematic view of a retaining device provided by an embodiment of the present invention, which only shows a part related to an embodiment of the present invention for convenience of description, and the detailed description is as follows:
the utility model provides a pair of lightweight compact electromagnetism repulsion mechanism includes: a driving device 1, a buffer device 2 and a holding device 3; the driving device 1 is provided with an opening coil 11, a closing coil 12 and a repulsive force disc 13; the opening coil 11 and the closing coil 12 are arranged oppositely, and the repulsive force disc 13 penetrates through a through hole of the opening coil 11;
the buffer device 2 is arranged opposite to the repulsive force disc 13, and the upper part of the buffer device 2 passes through a through hole of the closing coil 12. Because the speed requirement of the operating mechanism on the switching action is lower relative to the switching-off speed, the number of turns of the switching-on coil can be less than that of the switching-off coil, and the size of a through hole of the switching-on coil is designed according to the size of the outer diameter of the switching-off buffer during design. The design enables the buffer device and the driving device to share the axial space, greatly reduces the axial height of the operating mechanism and is beneficial to the miniaturization of products. The damping means 2 may be a hydraulic damper, a spring damper or a polyurethane material damper, preferably a hydraulic damper in this example, which may improve the mechanical life of the mechanism due to less impact of the hydraulic damper on the mechanism, but which is relatively more complex in design.
As shown in fig. 2, the holding device 3 includes: the connecting plate 31, the piston 32, the spring 33, the spring base 34, the bolt 35 and the housing 36; wherein, both ends of the connecting plate 31 are provided with through holes, one end is hinged with the repulsion plate 13, and the other end is hinged with the piston 32. Both ends of the connecting plate 31 are provided with through holes, one end is hinged with the repulsive force plate 13, and the other end is hinged with the piston 32. The housing 36 has a cylindrical cavity therein, and the piston 32, the spring 33, and the spring seat 34 are disposed in the cavity of the housing 36. A spring 33 is arranged between the piston 32 and a spring seat 34. The inner diameter of the housing 36 is a clearance fit with the outer diameters of the piston 32 and the spring mount 34, and the piston 32 and the spring mount 34 are slidable within the housing 36. One face of the housing 36 is provided with a threaded hole, and the bolt 35 passes through the threaded hole of the housing 36 to contact the spring seat 34.
As an embodiment of the present invention, the hinge connection may be implemented by a pin or a bearing, wherein the pin connection is adopted to make the structure of the hinge connection simpler; the friction force of the hinge connection is smaller by adopting the bearing connection, the abrasion of the holding device when the mechanism is operated is reduced, and the output force of the mechanism when the mechanism is operated is reduced, so that the power supply volume and the cost are reduced.
Wherein, a threaded hole is arranged on the outer shell 36, and the bolt 35 passes through the threaded hole of the outer shell 36 to contact with the spring base 34. After design and shaping, the compression amount of the spring 33 can be adjusted by adjusting the position of the bolt 35, and the opening and closing holding force of the mechanism is further adjusted.
As the preferred embodiment of the present invention, the inner diameter of the housing 36 is in clearance fit with the outer diameters of the piston 32 and the spring base 34, and the piston 32 and the spring base 34 can slide inside the housing 36, as an embodiment of the present invention, the lubricant is added inside the housing for lubrication, so as to reduce the friction force when the piston moves, avoid the jamming, and enable the opening and closing operation of the electromagnetic repulsion mechanism to be smoothly performed.
The embodiment of the utility model provides an in, repulsion dish 13, connecting plate 31, piston 32, spring base 34, bolt 35 and shell 36's material can be superhard aluminum alloy, and for carbon steel and other alloy steel materials, superhard aluminum alloy's density is littleer, and structural strength is higher to the moving part quality of mechanism is littleer, has reduced power supply volume and cost.
In the embodiment of the present invention, the outer diameters of the opening coil 11, the closing coil 12 and the repulsive disc 13 are the same. The electromagnetic repulsion force generated between the repulsion disc 13 and the coil is the largest when the sizes of the repulsion disc and the coil are consistent, and the driving efficiency of the electromagnetic repulsion mechanism obtains the optimal value, so that the outer diameter of the repulsion disc is consistent with the outer diameter of the opening and closing coil. According to simulation and test results, when the outer diameters of the opening coil and the closing coil are consistent with the outer diameter of the repulsion plate, the driving efficiency of the electromagnetic repulsion mechanism is highest.
Through the optimization of above-mentioned structure, compare the electromagnetic repulsion mechanism of general design, not only reduced the total mass of moving part, simultaneously under the prerequisite of guaranteeing to keep, shock-absorbing capacity, effectively improved electromagnetic repulsion mechanism's drive efficiency and maintainability, reduced the volume and the cost of product.
For further explanation, the light-weight compact electromagnetic repulsion mechanism according to the embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein:
when the electromagnetic repulsion mechanism performs opening operation, the external power supply discharges to the opening coil 11, and the discharge current generates a rapidly changing magnetic field in the space. Due to the electromagnetic induction principle, the axial component of the magnetic field generates induced electromotive force in the repulsion disk 13, and the radial component of the magnetic field interacts with the induced eddy current in the repulsion disk 13 to generate electromagnetic repulsion, so as to drive the repulsion disk 13 and the movable part of the mechanism to move towards the opening direction of the mechanism. During the movement, the spring 33 in the holding device 3 is always in a compressed state. When the repulsive disc 13 moves to the opening position, the bottom end of the repulsive disc 13 collides with the upper portion of the damper 2. Finally, the repulsion plate 13 is stabilized in the opening position of the mechanism by the opening holding force provided by the holding device 3 and the damping force provided by the damping device 2.
When the electromagnetic repulsion mechanism performs a closing operation, the external power supply discharges to the closing coil 12, and the discharge current generates a rapidly changing magnetic field in the space. Due to the electromagnetic induction principle, the axial component of the magnetic field generates induced electromotive force in the repulsion disk 13, and the radial component of the magnetic field interacts with the induced eddy current in the repulsion disk 13 to generate electromagnetic repulsion, so as to drive the repulsion disk 13 and the movable part of the mechanism to move towards the closing direction of the mechanism. During the movement, the spring 33 in the holding device 3 is always in a compressed state. The repulsive disc 13 is finally stabilized in the closing position of the mechanism (i.e. the position in figure 1) by the closing holding force provided by the holding means 3.
It will be understood by those skilled in the art that the foregoing is merely a preferred embodiment of the present invention, and is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. A lightweight compact electromagnetic repulsion mechanism is characterized by comprising a driving device (1), a buffer device (2) and a holding device (3);
the driving device (1) comprises a switching-off coil (11), a switching-on coil (12) and a repulsive force disc (13); the opening coil (11) and the closing coil (12) are arranged oppositely, and the upper end of the repulsive force disc (13) penetrates through a through hole of the opening coil (11);
the buffer device (2) is arranged opposite to the repulsion disc (13), and the upper part of the buffer device (2) penetrates through a through hole of the closing coil (12);
the holding device (3) is connected with the repulsion plate (13), and the holding force can be adjusted by adjusting the rigidity of a spring in the holding device (3), the screwing depth of a bolt or the length of a connecting plate during work.
2. Electromagnetic repulsion mechanism according to claim 1, characterized in that it comprises two holding means (3), both connected to said repulsion disc (13) and arranged axisymmetrically with respect to said repulsion disc (13).
3. An electromagnetic repulsion mechanism according to claim 1, characterized in that said holding means (3) comprises: the device comprises a connecting plate (31), a piston (32), a spring (33), a spring base (34), a bolt (35) and a shell (36);
the shell (36) is internally of a cylindrical cavity structure, and the piston (32), the spring (33) and the spring base (34) are all arranged in the cylindrical cavity;
the spring (33) being arranged between the piston (32) and the spring seat (34),
one end of the connecting plate (31) is connected with the piston (32), and the other end is connected with the repulsive force disc (13).
4. An electromagnetic repulsion mechanism according to claim 3, characterized in that the inner diameter of said housing (36) is clearance fit with the outer diameters of said piston (32) and said spring mount (34), and said piston (32) and said spring mount (34) are slidable within the interior of said housing (36).
5. An electromagnetic repulsion mechanism according to any of claims 3-4, characterized in that through holes are provided on said piston (32), said repulsion disk (13) and both ends of said connecting plate (31), one end of said connecting plate (31) is connected to said piston (32) through a through hole, and the other end is connected to said repulsion disk (13) through a through hole.
6. An electromagnetic repulsion mechanism according to claim 5, characterized in that said connection plate (31) and said piston (32), and said connection plate (31) and said repulsion plate (13) are hinged by means of pins or bearings.
7. An electromagnetic repulsion mechanism according to claim 3, characterized in that said housing (36) is provided with a threaded hole, and said bolt (35) passes through the threaded hole of the housing (36) to contact the spring seat (34).
8. An electromagnetic repulsion mechanism according to claim 3, characterized in that the materials of said repulsion disk (13), attachment plate (31), piston (32), spring seat (34), bolt (35) and housing (36) are all superhard aluminum alloy.
9. An electromagnetic repulsion mechanism according to claim 1, characterized in that said cushioning means (2) is a hydraulic cushion, a spring cushion or a polyurethane material cushion.
10. The electromagnetic repulsion mechanism according to claim 1, characterized in that the outer diameters of said opening coil (11), said closing coil (12) and said repulsion disk (13) are the same.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920874603.2U CN210073746U (en) | 2019-06-12 | 2019-06-12 | Lightweight compact electromagnetic repulsion mechanism |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201920874603.2U CN210073746U (en) | 2019-06-12 | 2019-06-12 | Lightweight compact electromagnetic repulsion mechanism |
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| CN210073746U true CN210073746U (en) | 2020-02-14 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110223892A (en) * | 2019-06-12 | 2019-09-10 | 华中科技大学 | A kind of lightweight compact electromagnetic repulsion mechanism |
| CN113675048A (en) * | 2021-09-15 | 2021-11-19 | 天津工业大学 | Permanent magnet and spring bidirectional retaining mechanism |
| CN113889365A (en) * | 2020-07-02 | 2022-01-04 | 陕西新通智能科技有限公司 | Anti-impact hollow movable iron core of electromagnetic switch and manufacturing method thereof |
-
2019
- 2019-06-12 CN CN201920874603.2U patent/CN210073746U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110223892A (en) * | 2019-06-12 | 2019-09-10 | 华中科技大学 | A kind of lightweight compact electromagnetic repulsion mechanism |
| CN113889365A (en) * | 2020-07-02 | 2022-01-04 | 陕西新通智能科技有限公司 | Anti-impact hollow movable iron core of electromagnetic switch and manufacturing method thereof |
| CN113889365B (en) * | 2020-07-02 | 2024-05-14 | 陕西新通智能科技有限公司 | Lost motion iron core in electromagnetic switch anti-impact and manufacturing method thereof |
| CN113675048A (en) * | 2021-09-15 | 2021-11-19 | 天津工业大学 | Permanent magnet and spring bidirectional retaining mechanism |
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