Motor stator sealing structure, manufacturing method and underwater motor

Abstract

This invention discloses a motor stator sealing structure, manufacturing method, and underwater motor. The motor stator sealing structure includes: a housing, a stator assembly, a shielding sleeve, potting compound, and a sealing ring. The manufacturing method of the motor stator sealing structure includes the following steps: assembling the housing, stator assembly, and shielding sleeve; inserting the potting compound into the housing to seal the bottom of the housing and prevent potting compound leakage from the bottom during potting; injecting potting compound under negative pressure and heating and allowing it to stand until the potting compound cures; trimming the potting compound and machining a sealing groove on it; and installing the sealing ring in the sealing groove. Compared with the prior art, the motor stator sealing structure provided by this invention fills the space between the shielding sleeve and the housing with potting compound, which enhances the pressure resistance of the shielding sleeve and improves the sealing performance under high pressure. When underwater, the water in the underwater motor provided by this invention passes through the middle of the shielding sleeve, eliminating the need for a dynamic sealing device and a pressure compensator, greatly simplifying the structure.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to a motor stator sealing structure, manufacturing method, and underwater motor. Background Technology

[0002] Underwater motors, as the core power unit of underwater unmanned equipment and an essential tool for underwater tasks such as seabed exploration, sampling, and underwater construction, undoubtedly represent the main development trend of electric propulsion devices. Due to the unique nature of the underwater environment, sealing under the high pressure of the deep sea is a common problem faced and must be solved by underwater instruments and equipment. Currently, pressure compensation and stator shielding compensation are the most commonly used sealing methods. However, both pressure compensation and stator shielding compensation have the following problems:

[0003] Pressure compensation technology involves filling the motor stator with insulating oil, sealing the rotating shaft with a dynamic seal, and using a pressure compensator to maintain the oil pressure inside the motor slightly higher than the external seawater pressure to prevent seawater from entering the motor. However, the reliability of the dynamic seal and the pressure compensator remains to be verified, and both have high maintenance costs.

[0004] Stator shielding compensation technology uses a shielding sleeve to separate the stator and rotor. The shielding sleeve is welded to the housing, and the middle section of the iron core withstands seawater pressure through the shielding sleeve. Because there is no additional filler between the stator iron core and the shielding sleeve, the shielding sleeve is prone to deformation or even damage under the huge water pressure, leading to seal failure. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and to propose a motor stator sealing structure, manufacturing method, and underwater motor, thereby solving the technical problem of poor sealing effect in existing underwater motors.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a motor stator sealing structure, comprising: a housing, the housing being a hollow structure open at both ends; a stator assembly, the stator assembly being an annular structure coaxially arranged within the housing; a shielding sleeve, the shielding sleeve being coaxially arranged within the stator assembly; a potting compound, the potting compound filling the space between the shielding sleeve and the housing, and the potting compound encapsulating the stator assembly; and a sealing ring, wherein both ends of the housing and the end of the potting compound facing outwards from the housing form a plurality of sealing grooves, and the sealing ring is correspondingly arranged within the sealing grooves.

[0008] In some embodiments, a first protrusion extends radially inward from the inner wall of the housing, and one end of the shielding sleeve abuts against the first protrusion. The shielding sleeve, the first protrusion, and the inner wall of the housing together form a receiving space for filling the potting compound.

[0009] In some embodiments, the inner wall of the first boss extends radially inward to form a stop, and one end of the shielding sleeve abuts against the stop.

[0010] In some embodiments, a mounting groove is also formed at the connection between the potting compound and the first boss, and the sealing ring is also disposed in the mounting groove.

[0011] In some embodiments, a threaded hole is formed at each end of the housing, and the threaded holes are evenly distributed around the axis of the housing.

[0012] In some embodiments, the potting compound is an epoxy resin potting compound.

[0013] Secondly, the present invention also provides a method for manufacturing a motor stator sealing structure, comprising the following steps: assembling the housing, the stator assembly, and the shielding sleeve; inserting a potting cylinder into the housing to seal the bottom of the housing to prevent the potting compound from leaking from the bottom during potting; injecting the potting compound under negative pressure; heating and allowing it to stand until the potting compound cures; trimming the potting compound and machining the sealing groove on the potting compound; and installing the sealing ring in the sealing groove.

[0014] In some embodiments, one end of the shielding sleeve is fixed by a potting cap, the outer edge of the potting cap abuts against the inner wall of the housing, the potting cap has a groove that mates with one end of the shielding sleeve, and the potting cap is used to limit the radial sway of the shielding sleeve.

[0015] In some embodiments, the coefficient of thermal expansion of the potting cartridge is greater than that of the housing.

[0016] Thirdly, the present invention also provides an underwater motor, including a motor stator sealing structure.

[0017] Compared with the prior art, the motor stator sealing structure provided by the present invention fills the space between the shielding sleeve and the housing with potting compound, which enhances the pressure resistance of the shielding sleeve and improves the sealing performance under high pressure. When the underwater motor provided by the present invention is underwater, water passes through the middle of the shielding sleeve, eliminating the need for a dynamic sealing device to isolate the inside and outside of the motor and eliminating the need for a pressure compensator to achieve internal and external pressure balance. Compared with pressure compensation methods, the structure is greatly simplified. Attached Figure Description

[0018] Figure 1This is a schematic diagram of the motor stator sealing structure provided in an embodiment of the present invention from one perspective;

[0019] Figure 2 This is a schematic diagram of the motor stator sealing structure provided in an embodiment of the present invention from another perspective;

[0020] Figure 3 This is a cross-sectional view of the motor stator sealing structure provided in this embodiment of the invention before glue injection;

[0021] Figure 4 This is a cross-sectional view of the motor stator sealing structure provided in this embodiment of the invention after glue injection and during a sealing test.

[0022] Figure 5 yes Figure 3 Cross-sectional view of the middle casing;

[0023] Figure 6 This is a flowchart of the manufacturing method of the motor stator sealing structure provided in the embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of the filling cartridge structure;

[0025] Figure 8 This is a schematic diagram of the potting cap structure;

[0026] Figure 9 yes Figure 6 A schematic diagram of the structure during the gluing process. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be 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 and not intended to limit the invention.

[0028] To address the technical problem of poor sealing performance in underwater motors, this invention provides a motor stator sealing structure that can improve the sealing performance of underwater motors.

[0029] Please see Figures 1 to 4 , Figure 1 This is a schematic diagram of the motor stator sealing structure provided in an embodiment of the present invention from one perspective; Figure 2 This is a schematic diagram of the motor stator sealing structure provided in an embodiment of the present invention from another perspective; Figure 3 This is a cross-sectional view of the motor stator sealing structure provided in an embodiment of the present invention; Figure 4 This is a cross-sectional view of the motor stator sealing structure provided in this embodiment of the invention after glue injection and during a sealing test.

[0030] The motor stator sealing structure includes: a housing 1, a stator assembly 2, a shielding sleeve 3, potting compound 4, and a sealing ring 5. The housing 1 is a hollow structure open at both ends, used to accommodate various other equipment. The stator assembly 2 is a ring-shaped structure, coaxially arranged within the housing 1. The shielding sleeve 3 is coaxially arranged within the stator assembly 2, meaning the stator assembly is located between the shielding sleeve 3 and the housing 1. The potting compound 4 fills the space between the shielding sleeve 3 and the housing 1, and also encapsulates the stator assembly 2.

[0031] Several sealing grooves 11 are formed at both ends of the housing 1 and at the end of the potting compound 4 facing outward from the housing 1, and sealing rings 5 ​​are arranged in the sealing grooves 11 respectively.

[0032] The stator sealing structure of this motor fills the space between the shielding sleeve 3 and the housing 1 with potting compound 4. The potting compound 4 enhances the compressive strength of the shielding sleeve 3, making it less prone to deformation and improving the sealing performance under high pressure. At the same time, after the potting compound 4 solidifies, it can also be used to process the sealing groove 11 to install the sealing ring 5.

[0033] In some embodiments, a ring of threaded holes 12 is formed at each end of the housing 1, and the threaded holes 12 are evenly distributed around the axis of the housing 1. Through the threaded holes 12, the housing 1 can be connected to the cover plate of the motor to assemble an underwater motor. The threaded holes 12 evenly distributed around the axis can make the cover plate more evenly stressed and the sealing effect better.

[0034] Please see Figure 5 In some embodiments, a first boss 13 extends radially inward from the inner wall of the housing 1, and one end of the shielding sleeve 3 abuts against the first boss 13. The shielding sleeve 3, the first boss 13, and the inner wall of the housing 1 together form a receiving space for preventing the stator assembly 2 and the filling potting compound 4 from entering.

[0035] In some embodiments, a stop 14 extends radially inward from the inner wall of the first boss 13. One end of the shielding sleeve 3 abuts against the stop 14, and the end also abuts against the inner wall of the first boss 13. The stop 14 and the first boss 13 cooperate to achieve coaxial positioning of the shielding sleeve 3.

[0036] Please see Figure 4 In some embodiments, a mounting groove 15 is also formed at the connection between the potting compound 4 and the first boss 13, and a sealing ring 5 is also provided in the mounting groove 15. Due to thermal expansion and contraction, the potting compound 4 is difficult to bond tightly to the inner wall of the housing 1 after solidification, and gaps are easily generated. Under strong water pressure, these gaps will be further enlarged, which will lead to the destruction of the stator sealing structure of the motor. Therefore, a sealing ring 5 should also be provided here to prevent water leakage.

[0037] Figure 4This is a cross-sectional view of the motor stator sealing structure provided in this embodiment of the invention during a sealing test after glue injection. The motor stator sealing structure has cover plates connected to both ends, one of which has a water injection hole through which high-pressure water is injected into the motor stator sealing structure. This simulates a scenario where the shielding sleeve 3 is filled with water underwater. Both ends and the middle of the shielding sleeve 3 are subjected to water pressure. The left end is sealed by machining an installation groove and installing a sealing ring 5. The middle part is filled with potting compound 4 to enhance the pressure resistance of the shielding sleeve 3 and prevent deformation. The right end is also sealed by machining a sealing groove and installing a sealing ring 5. These three measures work together to protect the stator assembly 2, achieving a better waterproof sealing effect.

[0038] In some embodiments, the stator assembly 2 includes a stator, a core, and windings, which are connected together in a conventional manner to form the stator assembly 2.

[0039] In some embodiments, since the shielding sleeve 3 does not need to be welded to the housing 1, the shielding sleeve 3 can be made of composite materials, such as carbon fiber.

[0040] In some embodiments, potting compound 4 is an epoxy resin potting compound.

[0041] This invention provides a method for manufacturing a motor stator sealing structure. Please refer to [link / reference]. Figure 6 , Figure 6 This is a flowchart of a method for manufacturing a motor stator sealing structure according to an embodiment of the present invention. The manufacturing method includes the following steps:

[0042] S1. Assemble the housing 1, stator assembly 2, and shielding sleeve 3 according to the above connection method. Insert the potting cylinder 6 into the housing 1 to seal the bottom of the housing 1, forming... Figure 3 The structure shown is as follows. During potting, this structure follows... Figure 3 Place it with the left end down and the right end up, that is... Figure 3 Rotate 90° counterclockwise. The potting cartridge 6 prevents the potting compound 4 from leaking from the bottom during potting.

[0043] Combination Figure 7 In some embodiments, the outer diameter of the potting cylinder 6 matches the inner diameter of the stop 14, and is slightly smaller than the inner diameter of the shielding sleeve 3. One end of the potting cylinder 6 extends radially outward to form a retaining ring. After the potting cylinder 6 is installed, the retaining ring abuts and fixes against the first boss 13, and provides a sealing effect to prevent the potting compound 4 from leaking out during potting. At the same time, the other end of the potting cylinder 6 is inserted into the shielding sleeve 4, forming a gap between them. During potting, the potting compound will also enter this gap, covering the inside of the shielding sleeve 3 with a layer of potting compound 4. It is easy to understand that other parts on the housing 1 that may cause the potting compound 4 to leak also need to be sealed, such as the junction box, the mating area between the shielding sleeve 3 and the stop 14, etc.

[0044] Please see Figure 8 In some embodiments, the end of the shielding sleeve 3 away from the retaining ring is fixed by a potting cap 7, which has a groove 71 that engages with one end of the shielding sleeve 3. The potting cap 7 is used to limit the radial sway of the shielding sleeve 3.

[0045] Please see Figure 9 In some embodiments, the potting cap 7 does not adopt a circular structure, but rather a long strip structure, with part of its outer edge abutting against the inner wall of the housing 1, and the other part of its outer edge forming a gap between itself and the inner wall of the housing 1 for injecting the potting compound 4. Figure 9 The potting compound 4 is injected at the location indicated by the middle arrow. In other embodiments, other structures can also be used, as long as a section is left blank for potting the compound on the basis of the circular structure.

[0046] S2. Inject potting compound 4 under negative pressure, heat and let stand until potting compound 4 cures. The negative pressure environment can promote the expulsion of air bubbles in potting compound 4, improving the potting quality.

[0047] S3. Trim the potting compound 4 and machine a sealing groove 11 on the potting compound 4, then install the sealing ring 5 into the sealing groove 11. In some embodiments, a mounting groove 15 is also machined at the connection between the potting compound 4 and the first boss 13, and a sealing ring 5 is also inserted into the mounting groove 15 for sealing, forming... Figure 4 The structure shown.

[0048] In some embodiments, the coefficient of thermal expansion of the potting cylinder 6 is greater than that of the housing 1. Before potting in step S2, the stator sealing structure of the motor is heated to improve the flowability of the potting compound 4. Both the potting cylinder 6 and the housing 1 expand due to heat, but the potting cylinder 6 expands more, thereby radially pressing the first protrusion 13 outwards. This ensures a tight fit between the potting cylinder 6 and the first protrusion 13, resulting in a better sealing effect and preventing the potting compound 4 from leaking out during potting.

[0049] The present invention provides an underwater motor, which includes the above-mentioned motor stator sealing structure, as well as other structures such as rotor and cover. The rotor is set inside the shielding sleeve, and the cover is connected to both ends of the housing 1 through threaded holes 12. The cover presses the sealing ring 5 in the sealing groove 11 to achieve the sealing effect.

[0050] The underwater motor provided by this invention allows water to pass through the middle of the shielding sleeve 3 when underwater, meaning the rotor is immersed in water. It eliminates the need for a dynamic sealing device to isolate the motor from the outside, and eliminates the need for a pressure compensator to balance the internal and external pressures, greatly simplifying the structure compared to pressure compensation methods.

[0051] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A motor stator sealing structure, characterized in that, include: The housing is a hollow structure with openings at both ends; A stator assembly, wherein the stator assembly is a circular ring structure and is coaxially arranged within the housing; A shielding sleeve, which is coaxially arranged within the stator assembly; A potting compound is used to fill the space between the shielding sleeve and the housing, and the potting compound also encapsulates the stator assembly. The sealing ring has several sealing grooves formed at both ends of the housing and at the end of the potting compound facing outward from the housing, and the sealing ring is arranged in the sealing grooves accordingly. The inner wall of the housing extends radially inward to form a first protrusion, and one end of the shielding sleeve abuts against the first protrusion. The shielding sleeve, the first protrusion, and the inner wall of the housing together form a receiving space for filling the potting compound. A mounting groove is also formed at the connection between the potting compound and the first boss, and the sealing ring is also provided in the mounting groove.

2. The motor stator sealing structure according to claim 1, characterized in that, The inner wall of the first boss extends radially inward to form a stop, and one end of the shielding sleeve abuts against the stop.

3. The motor stator sealing structure according to claim 1, characterized in that, A threaded hole is formed at each end of the housing, and the threaded holes are evenly distributed around the axis of the housing.

4. The motor stator sealing structure according to claim 1, characterized in that, The potting compound is an epoxy resin potting compound.

5. A method for manufacturing a motor stator sealing structure according to any one of claims 1-4, characterized in that, Includes the following steps: Assemble the housing, the stator assembly, and the shielding sleeve, and insert the potting tube into the housing to seal the bottom of the housing and prevent the potting compound from leaking from the bottom during potting; The potting compound is injected under negative pressure and heated and allowed to stand until the potting compound cures. The potting compound is trimmed and the sealing groove is machined into the potting compound, and the sealing ring is installed in the sealing groove.

6. The method for manufacturing the motor stator sealing structure according to claim 5, characterized in that, One end of the shielding sleeve is fixed by a potting cap. The outer edge of the potting cap abuts against the inner wall of the housing. The potting cap has a groove that mates with one end of the shielding sleeve. The potting cap is used to limit the radial sway of the shielding sleeve.

7. The method for manufacturing the motor stator sealing structure according to claim 5, characterized in that, The coefficient of thermal expansion of the potting cylinder is greater than that of the housing.

8. An underwater motor, characterized in that, It includes the motor stator sealing structure as described in any one of claims 1-4.

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