Multi-point uniform distribution swelling pressure sealing method for stator slot and application of multi-point uniform distribution swelling pressure sealing method

Abstract

The invention belongs to the field of motor stator notch encapsulation, and discloses a multi-point uniform distribution swelling pressure sealing stator notch method, which comprises the following steps of: placing an upper clamping plate on the end surface of a stator core, embedding an elastic strip-shaped filler and a lower clamping plate into an inner cavity of the core, and fastening the upper clamping plate and the lower clamping plate by arranging multi-point uniform distribution bolts in the process of fastening; and the elastic strip-shaped filler is compressed to expand outwards, so that gaps among the upper clamping plate, the iron core and the slot wedge are forcibly extruded and filled, and the gaps are well sealed. The problems that plugging and sealing operation efficiency is low, gap defects are formed due to the fact that pouring sealant in a notch is lost due to reverse filling in rubber paste filling, and cleaning of rubber paste for sealing is time-consuming and difficult to complete after pouring and curing are solved. And the problems of small extrusion force, uniformity deviation of extrusion force of each area, insufficient expansion deformation, loose sealing, easy leakage and the like when central point expansion is adopted are solved.

Description

Technical Field

[0001] The invention relates to a method for sealing stator slots by uniformly distributing expansion pressure at multiple points and application thereof, belonging to the technical field of potting of stator slots of motor stators. Background Art

[0002] The stator slot potting operation of the motor stator needs to fill the stator slot with potting glue to form an isolation at the slot to prevent foreign matter from penetrating and adhering to the coil slot, etc., to protect the stator slot. In the potting operation, an annular protective ring needs to be formed on the inside of the stator slot before potting to seal and solidify the potting glue at the slot. The tooth-shaped step gap formed by the height change of the iron core and the slot wedge in the inner cavity of the stator core brings great difficulties to the sealing of this part.

[0003] At present, rubber mud is generally used to fill and seal the gaps in the stator slots. However, there are several shortcomings: (1) The efficiency of rubber mud sealing is low. The rubber mud must be rolled into a cylinder and then glued to the gaps in the toothed steps section by section. The gaps must be checked for sealing by light transmission to confirm the sealing condition. (2) In order to avoid light transmission due to loose sealing, which may lead to leakage of glue during potting, the rubber mud must be repeatedly pressed and sealed. It is easy for the rubber mud to reversely penetrate into the toothed steps and occupy the original potting glue filling space at the end face of the slot wedge. This can easily cause the potting glue to fill the missing gaps and weaken the protective effect of the potting itself. (3) After the potting is baked and cured, the cleaning of the rubber mud used for sealing is troublesome and time-consuming. The rubber mud is easy to adhere to the iron core and the slot wedge. In particular, because the surface of the iron core is uneven, the rubber mud needs to be scraped off little by little during cleaning, but it is still difficult to clean thoroughly, affecting the appearance quality.

[0004] After searching, CN202022562590.0 discloses a stator slot potting expansion and pressure sealing device, including a lower pressure plate that can be embedded in the inner cavity of the stator core, an upper pressure plate coaxially superimposed on the lower pressure plate, and a sealing rubber ring sandwiched between the lower pressure plate and the upper pressure plate. The sealing rubber ring is sleeved on the lower pressure plate. The sealing rubber ring is squeezed and expanded outward and pressed into the stator core slot wedge as the lower pressure plate and the upper pressure plate are bolted together to expand and seal the stator core slot wedge. In this structure, the upper and lower pressure plates are used for bolt-tightening connection through screw holes, through holes and corresponding threaded holes. As the bolts are screwed in, the distance between the lower pressure plate and the upper pressure plate is shortened, squeezing the sealing rubber ring. In the face of the above-mentioned operational problems, the stator slot potting expansion and pressure sealing device is a single-point expansion and pressure sealing protection method fastened with a center point bolt, and its nesting material is a silicone block. However, this method has a single fastening point, too small extrusion pressure, deviation in uniformity of extrusion pressure in each area, and insufficient expansion and compression deformation. It cannot cope with medium and large-sized stators, as well as stators with large slot gaps. It is prone to problems such as poor sealing of gaps, leakage of potting glue, and frequent rework.

[0005] Therefore, it is very necessary to invent a multi-point uniform expansion and pressure sealing method for stator slots that can solve the problems of small center point expansion and pressure extrusion pressure, deviation in uniformity of extrusion pressure in each zone, insufficient expansion and pressure deformation, loose sealing and easy leakage. Summary of the invention

[0006] In view of the deficiencies of the above-mentioned prior art, the present invention discloses a method for sealing stator slots with uniform multi-point expansion and pressure, which solves the problems of low sealing efficiency, gap defects caused by missing slots due to reverse filling of rubber mud, time-consuming and difficult to thoroughly clean rubber mud used for sealing after potting and curing, as well as the problems of small extrusion pressure when using central point expansion and pressure, deviation in uniformity of extrusion pressure in each zone, insufficient expansion and pressure deformation, loose sealing and easy leakage.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: Disclosed is a method for sealing stator slots by multi-point uniform expansion and compression. An upper clamping plate is placed on the end surface of a stator core, and an elastic strip filler and a lower clamping plate are embedded in the inner cavity of the core. During the process of fastening the upper and lower clamping plates with multi-point uniformly distributed bolts, the elastic strip filler is compressed and expanded outward, thereby strongly squeezing and filling the gaps between the upper clamping plate, the core and the slot wedge, so as to achieve good sealing of the gaps.

[0008] Furthermore, the multi-point uniform distribution of the upper and lower clamping plates is achieved by arranging the first mounting wing plate and the second mounting wing plate in pairs on the inner edges of the upper and lower clamping plates. The structure of the upper clamping plate can be effectively arranged in coordination with the lower clamping plate, and the first mounting wing plate and the second mounting wing plate are evenly distributed circumferentially on the inner sides of the upper and lower clamping plates, and the upper and lower clamping plates are fastened by bolts, thereby forming a strong and uniform extrusion force in the longitudinal direction of the upper and lower clamping plates, fully and significantly extruding the elastic strip filler, and achieving the effect of effectively filling and sealing the gap in the stator slot.

[0009] Furthermore, the upper and lower clamping plates are coaxially arranged, and the elastic strip filler is composed of foam strips that are resistant to high temperatures and have good shrinkage. The elastic strip filler is composed of foam strips that are spliced ​​and sleeved on the outer peripheral surface of the lower clamping plate convex ring of the lower clamping plate, and abuts against the edge of the upper clamping plate. The foam strips are spliced ​​and compressed and can only expand outward, so as to strongly squeeze and fill the gaps between the upper clamping plate and the iron core and the slot wedge, so as to achieve good sealing of the gaps.

[0010] The foam strips with high temperature resistance and good shrinkage can be silicone foam strips: silicone foam strips are usually made of silicone rubber, have excellent high temperature resistance, and can remain stable in high temperature environments. They have good shrinkage and are suitable for occasions that require sealing and buffering.

[0011] You can also choose flame-retardant and heat-resistant sponge foamed silicone strips: This foam strip is not only resistant to high temperatures, but also has flame-retardant properties, and is suitable for occasions that require fire prevention and high temperature resistance. Its good shrinkage allows it to maintain its shape at high temperatures, ensuring the sealing effect. High temperature stability and good shrinkage ensure reliability and durability under various extreme conditions. When in use, the foam strip is squeezed evenly and fully at multiple points to form a strong and uniform squeezing force, achieving the effect of fully and significantly squeezing the foam strip (the maximum radial expansion on one side can reach 10mm, meeting the expansion and pressure sealing requirements of various models of stators), and effectively filling and sealing the gaps in the stator slots.

[0012] Furthermore, the number density of uniformly distributed bolt fastening points is adjusted according to the change in the inner diameter of the stator core and the size of the gap formed by the height difference between the core and the slot wedge in the radial direction. The size of the foam strip to be expanded can be determined according to the size of the gap, and then according to previous verification, it is determined whether to use 4-point uniform distribution, 6-point uniform distribution, 8-point uniform distribution or 10-point uniform distribution.

[0013] Furthermore, the upper clamping plate includes a groove structure formed by a top wall and an annular side wall, and the first mounting wing plate is arranged on the inner edge of the top wall.

[0014] Furthermore, the first mounting wing plate includes a bearing plate and a mounting hole, and the bearing plate is symmetrically arranged along the connecting line between the center of the mounting hole and the center of the top wall. The first mounting wing plate can effectively bear and position the bolts, and the bearing plate is a symmetrical structure, which can ensure that the upper clamping plate is evenly stressed when subjected to force, laying a foundation for subsequent effective plugging and sealing of the stator slot gap.

[0015] Furthermore, the lower clamping plate comprises a lower clamping plate convex ring, and the second mounting wing plate is arranged on the inner edge of the lower clamping plate convex ring. The lower clamping plate convex ring is arranged to cooperate with the annular side wall to effectively clamp the elastic strip filler.

[0016] Furthermore, the second mounting wing plate includes a positioning plate and a positioning hole, and the positioning plate has the same structure as the bearing plate.

[0017] Furthermore, the positioning hole is arranged on a side away from the inner edge of the convex ring of the lower clamping plate, and the positioning hole is a semi-open U-shaped step structure. The structure of the second mounting wing plate is arranged in pairs with the first mounting wing plate, wherein the centers of the mounting hole and the positioning hole coincide, ensuring that the installation directions of the multiple bolts arranged in the mounting hole and the positioning hole are consistent, and the upper and lower clamping plates can be uniformly stressed when stressed.

[0018] Another object of the present invention is to disclose the above-mentioned multi-point uniformly distributed expansion and pressure sealing method for stator slots for use in sealing and protecting operations during stator slot potting.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The multi-point uniformly distributed expansion and pressure sealing method for stator slots solves the problems of low sealing efficiency, missing slots and gap defects caused by reverse filling of rubber mud, time-consuming and difficult to thoroughly clean the rubber mud used for sealing after potting and curing, as well as the problems of small extrusion pressure when using central point expansion and pressure, deviation in uniformity of extrusion pressure in each zone, insufficient expansion and pressure deformation, loose sealing and easy leakage.

[0020] The multi-point uniformly distributed expansion and pressure sealing method of the stator slot of the present invention adopts an upper clamping plate, a lower clamping plate, and a foam strip with high temperature resistance and good shrinkage nested between the clamping plates, and a plurality of bolt fastening points are uniformly distributed in the inner circles of the upper and lower clamping plates, so as to form a strong and uniform extrusion force, so as to achieve the effect of fully and significantly extruding the foam strip and effectively filling and sealing the gap of the stator slot.

[0021] The lower clamping plate of the multi-point uniformly distributed expansion and pressure sealing stator slot method of the present invention is uniformly distributed with a plurality of half-open U-shaped step structures, which can clamp the bottom of the fastening external hexagonal bolts. The operation only needs to tighten the bolts at the upper clamping plate, which is very convenient.

[0022] The multi-point uniformly distributed expansion and pressure sealing stator slot method of the present invention has been tested in actual operation and has the advantages of good application performance, better sealing and protection performance, and saving operation time and rubber mud material costs.

[0023] The multi-point uniformly distributed expansion and pressure sealing stator slot method of the present invention can appropriately adjust the number density of uniformly distributed bolt fastening points according to the change in the inner diameter of the stator core and the size of the gap formed by the height difference between the core and the slot wedge in the radial direction, retain the core structure of the device, so as to be suitable for the sealing protection operation during the potting of multiple models of stator slots. At the same time, the method and the device have the advantages of simple application, high operating efficiency, and applicability to batch operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The figure is a schematic diagram of the overall structure of the device for sealing stator slots by expansion and pressure in the method for sealing stator slots by expansion and pressure at multiple points uniformly distributed in the present invention.

[0025] Figure 2 for Figure 1 A cross-sectional view of the expansion and compression sealing stator slot device taken at AA.

[0026] Figure 3 The present invention is a schematic structural diagram of an upper clamping plate of a stator slot sealing device using a multi-point uniformly distributed stator slot sealing method.

[0027] Figure 4 for Figure 3 A cross-sectional view of the upper clamping plate of the stator notch expansion and pressure sealing device at point BB.

[0028] Figure 5The present invention is a schematic structural diagram of an upper clamping plate of a stator slot sealing device using a multi-point uniformly distributed stator slot sealing method.

[0029] Figure 6 for Figure 5 A cross-sectional view of the upper clamping plate of the stator notch expansion and sealing device at CC.

[0030] Among them, 1-upper clamping plate, 11-first mounting wing plate, 111-bearing plate, 112-mounting hole, 12-top wall, 13-annular side wall, 2-lower clamping plate, 21-second mounting wing plate, 211-positioning plate, 212-positioning hole, 22-lower clamping plate convex ring, 3-elastic strip filler. DETAILED DESCRIPTION

[0031] For the convenience of explaining and understanding the present invention, the following Figure 1-6 The embodiments of the present invention are described in detail. Example 1

[0032] like Figure 1-6 As shown, in the multi-point uniformly distributed expansion and pressure sealing method of the stator slot in this embodiment, the upper clamping plate 1 is placed on the end face of the stator core, and the elastic strip filler 3 and the lower clamping plate 2 are embedded in the inner cavity of the core. During the process of fastening the upper and lower clamping plates with multi-point uniformly distributed bolts, the elastic strip filler is compressed and expanded outward, thereby strongly squeezing and filling the gap between the upper clamping plate and the core and the slot wedge, thereby achieving a good sealing of the gap.

[0033] The multi-point uniformly distributed expansion and pressure sealing stator slot method of this embodiment uses an expansion and pressure sealing stator slot device, including a coaxially arranged upper clamp plate 1 and a lower clamp plate 2, an elastic strip filler 3 is nested between the upper clamp plate 1 and the lower clamp plate 2, the upper clamp plate 1 includes a first mounting wing plate 11 uniformly distributed circumferentially on the inner side, and a second mounting wing plate 21 uniformly distributed circumferentially on the inner side of the lower clamp plate 2; the first mounting wing plate 11 and the second mounting wing plate 21 are relatively arranged for fixing the upper clamp plate 1 and the lower clamp plate 2.

[0034] An upper clamping plate 1, a lower clamping plate 2, and an elastic strip filler 3 nested between the clamping plates are used, and a first mounting wing plate 11 and a second mounting wing plate 12 are evenly distributed circumferentially on the inner sides of the upper and lower clamping plates. The upper and lower clamping plates are fastened by bolts, thereby forming a strong and uniform extrusion force in the longitudinal direction of the upper and lower clamping plates, fully and significantly squeezing the elastic strip filler, thereby achieving the effect of effectively filling and sealing the gap in the stator slot.

[0035] The upper clamping plate 1 includes a groove structure formed by a top wall 12 and an annular side wall 13, and a first mounting wing plate 11 is arranged at the inner edge of the top wall 12. The first mounting wing plate 11 includes a bearing plate 111 and a mounting hole 112, and the bearing plate 111 is symmetrically arranged along the connecting line between the center of the mounting hole 112 and the center of the top wall 12. In this embodiment, the top wall 12 and the annular side wall 13 are connected by an inclined connecting wall.

[0036] The structure of the upper clamping plate 1 can be effectively coordinated with the lower clamping plate 2. When in use, the upper clamping plate 1 is placed on the end face of the stator core, and the elastic strip filler 3 and the lower clamping plate 2 are embedded in the inner cavity of the core. During the process of tightening the upper and lower clamping plates with multi-point evenly distributed bolts, the elastic strip filler 3 is compressed and can only expand outward, thereby strongly squeezing and filling the gap between the upper clamping plate 1 and the core and the slot wedge, thereby achieving a good seal of the gap.

[0037] The first mounting wing plate 11 can effectively bear and position the bolts, and the bearing plate 111 is a symmetrical structure, which can ensure that the upper clamping plate is evenly stressed when subjected to stress, laying a foundation for subsequent effective plugging and sealing of the stator slot gap.

[0038] Specifically, the lower clamping plate 2 includes a lower clamping plate convex ring 22, and the second mounting wing plate 21 is arranged on the inner edge of the lower clamping plate convex ring 22. The lower clamping plate convex ring 22 is arranged to cooperate with the annular side wall 13 to effectively clamp the elastic strip filler 3. The second mounting wing plate 21 includes a positioning plate 211 and a positioning hole 212, and the positioning plate 211 has the same overall structure as the bearing plate 111. In this embodiment, the positioning hole 212 is arranged on the side away from the inner edge of the lower clamping plate convex ring 22, and is in the shape of a U-shaped groove. The positioning hole 212 is preferably a semi-open U-shaped step structure. The structure of the second mounting wing plate 21 is arranged in pairs with the first mounting wing plate 11, and is set to 8 pairs in this embodiment. The centers of the mounting hole 112 and the positioning hole 212 coincide, ensuring that the installation directions of the multiple bolts arranged in the mounting hole 112 and the positioning hole 212 are consistent, and the upper and lower clamping plates can be uniformly stressed when subjected to force. The lower clamping plate 2 of the present expansion and pressure sealing stator notch device is evenly distributed with a plurality of half-open U-shaped step structures, which can clamp the bottom of the fastening hexagonal bolts. The operation only needs to tighten the bolts at the upper clamping plate 1, which is extremely convenient.

[0039] The elastic strip filler 3 in this embodiment is composed of foam strips, which are sleeved on the outer peripheral surface of the lower clamping plate convex ring 22 of the lower clamping plate 2 and abut against the edge of the upper clamping plate 1. The foam strips are spliced ​​and compressed and can only expand outward, so as to strongly squeeze and fill the gap between the upper clamping plate 1 and the iron core and the slot wedge, so as to achieve a good sealing of the gap.

[0040] The multi-point uniformly distributed expansion and pressure sealing stator slot method and device of the present embodiment are structured as an upper clamping plate 1, a lower clamping plate 2, and a foam strip with high temperature resistance and good shrinkage nested between the clamping plates. It can be used at 180°C-200°C, and its elastic variation is 8 uniformly distributed bolt fastening points in the inner circle of the upper and lower clamping plates (according to the variation of the inner diameter of the stator core and the size of the gap formed by the height difference between the core and the slot wedge in the radial direction, the number density of the uniformly distributed bolt fastening points can be appropriately adjusted to achieve multi-point uniform and sufficient squeezing of the foam strip), thereby forming a strong and uniform squeezing force, achieving the effect of fully and significantly squeezing the foam strip (the maximum radial expansion of 10mm on one side can meet the expansion and pressure sealing requirements of various types of stators), and effectively filling and sealing the gap in the stator slot. The invention solves the problems of low efficiency of rubber mud sealing operation in existing slot potting operation mode, gaps formed by reverse filling of rubber mud in the potting glue filling space, troublesome and time-consuming cleaning of rubber mud used for sealing after potting baking and curing, small extrusion pressure at the center point, deviation in uniformity of extrusion pressure in each zone, insufficient deformation due to expansion and pressure, loose sealing and easy leakage, etc., so as to improve the potting operation efficiency, reduce labor intensity, improve the potting protection quality, reduce the potting operation cost, etc., and meet the requirements of simple operation and application, and rapid batch sealing of various types of stator slots.

[0041] The above are only embodiments of the present invention. The invention is not limited to the field involved in this implementation case. The common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the content of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for sealing stator slots by uniformly distributing expansion pressure at multiple points, characterized in that: The upper clamping plate (1) is placed on the end surface of the stator core, and the elastic strip filler (3) and the lower clamping plate (2) are embedded in the inner cavity of the core. During the process of fastening the upper and lower clamping plates with bolts evenly distributed at multiple points, the elastic strip filler (3) is compressed and expanded outward, thereby strongly squeezing and filling the gap between the upper clamping plate (1) and the core and the slot wedge, thereby achieving a good sealing of the gap.

2. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 1, characterized in that: The multi-point uniform distribution of the upper and lower clamping plates is achieved by arranging a first mounting wing plate (11) and a second mounting wing plate (21) in pairs on the inner edges of the upper and lower clamping plates.

3. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 2, characterized in that: The upper clamping plate (1) and the lower clamping plate (2) are coaxially arranged, and the elastic strip filler (3) is composed of foam strips with high temperature resistance and shrinkage properties.

4. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 3, characterized in that: The number density of uniformly distributed bolt fastening points is adjusted according to the change in the inner diameter of the stator core and the size of the gap formed by the height difference between the core and the slot wedge in the radial direction.

5. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 4, characterized in that: The upper clamping plate (1) comprises a groove-shaped structure formed by a top wall (12) and an annular side wall (13), and the first mounting wing plate (11) is arranged on the inner edge of the top wall (12).

6. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 5, characterized in that: The first mounting wing plate (11) comprises bearing plates (111) and (112), wherein the bearing plate (111) is symmetrically arranged along a connecting line between the center of the mounting hole (112) and the center of the top wall (12).

7. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 5, characterized in that: The lower clamping plate (2) comprises a lower clamping plate convex ring (22), and the second mounting wing plate (21) is arranged on the inner edge of the lower clamping plate convex ring (22).

8. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 7, characterized in that: The second mounting wing plate (21) comprises a positioning plate (211) and a positioning hole (212); the positioning plate (211) has the same structure as the bearing plate (111).

9. The method for sealing stator slots by multi-point uniform expansion and pressure according to claim 8, characterized in that: The positioning hole (212) is arranged on a side away from the inner edge of the lower clamping plate convex ring (22), and the positioning hole (212) is a semi-open U-shaped step structure.

10. A method for sealing stator slots by uniformly distributing expansion pressure at multiple points as claimed in any one of claims 1 to 9, used for sealing and protecting operations during potting of stator slots.

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