Labyrinth water-proof structure for electric machine

Abstract

This application relates to the field of motor waterproofing technology, and in particular to a labyrinth waterproofing structure for motors, comprising a shaft, an end cover, and an integrated bushing; both the end cover and the integrated bushing are fitted onto the output end of the shaft, and at least a portion of the integrated bushing contacts the end cover; the side of the integrated bushing near the end cover has several protrusions and several grooves, and the side of the end cover near the integrated bushing has grooves and protrusions that match the integrated bushing; the integrated bushing and the end cover are connected by several protrusions and several grooves, and the connection portion between the integrated bushing and the end cover is filled with grease. This application has the effect of increasing the waterproofing of the motor.

Description

Technical Field

[0001] This application relates to the field of waterproofing technology for electric motors, and in particular to a labyrinth waterproofing structure for electric motors. Background Technology

[0002] With the development of science and technology, more and more fields are gradually moving towards mechanization. As the most basic driving component of mechanization, the electric motor has a wide range of applications. Furthermore, with the development of technology, new requirements have been put forward for various performance aspects of the electric motor.

[0003] In existing technologies, motors generally have limited sealing, thus requiring a clean and dry operating environment. This significantly restricts their use. In environments with high humidity or dust, moisture or impurities can easily be drawn into the motor. Some motors enhance their waterproofing by coating the shaft and bushing with grease, but due to relative sliding between the shaft and bushing, the grease is primarily used as a lubricant. Some moisture can even seep into the motor from the output end of the shaft or the gap between the bushing and the end cover, causing water ingress and corrosion of the bearings, leading to bearing seizure. Furthermore, moisture ingress can cause short circuits and burnout in the rotor and stator windings, significantly impacting the motor's safety and lifespan.

[0004] Therefore, how to increase the waterproofness of motors has become an urgent problem to be solved in this field. Summary of the Invention

[0005] To increase the waterproofness of motors, this application provides a labyrinth waterproof structure for motors.

[0006] The labyrinth waterproof structure for electric motors provided in this application adopts the following technical solution: A labyrinth waterproof structure for an electric motor includes a shaft, an end cap, and an integrated bushing. Both the end cap and the integrated bushing are fitted onto the output end of the shaft, with at least a portion of the integrated bushing contacting the end cap. The integrated bushing has several protrusions and grooves on the side near the end cap, and the end cap has matching grooves and protrusions on the side near the integrated bushing. The integrated bushing and the end cap are connected via several protrusions and several grooves, and the connection portion between the integrated bushing and the end cap is filled with grease.

[0007] By adopting the above technical solution, several protrusions and grooves that match each other between the integrated bushing and the end cover are used to extend the radial distance and increase the path for water vapor to enter the motor. The protrusions also ensure that water vapor must accumulate to a certain extent before it can enter the motor. The grease filling the space between the integrated bushing and the end cover fills the tiny gap between them, providing a certain degree of sealing. Furthermore, the grease has strong hydrophobicity, which can isolate water vapor that has penetrated between the integrated bushing and the end cover, preventing water vapor from seeping into the motor through the gap between the bushing and the end cover, thus increasing the motor's waterproofness.

[0008] Preferably, the integral bushing includes a base plate, the base plate having a first through hole in the middle for the rotating shaft to pass through, the diameter of the first through hole matching the diameter of the rotating shaft; the base plate having a first boss along the axial direction on the side near the end cap, the first boss being coaxial with the first through hole; and the base plate having a second boss along the axial direction on the side away from the end cap, the second boss being coaxial with the first through hole.

[0009] By adopting the above technical solution, the first boss is equivalent to a bushing, and the second boss is equivalent to a gasket. The first boss is used to limit the position of the rotating shaft and the positional relationship between the rotating shaft and the bearing. The first through hole is used for the rotating shaft to pass through. The first boss, the second boss and the first through hole are all coaxially arranged to ensure that the integrated bushing is evenly stressed.

[0010] Preferably, the substrate has a first groove and a second groove coaxially arranged on the side near the end cap; the outer diameter of the first groove is smaller than the inner diameter of the second groove; the depth of the first groove is greater than the depth of the second groove; and the width of the first groove is greater than the width of the second groove.

[0011] By adopting the above technical solution, the distance for water vapor to enter the motor is increased by using the first and second grooves set coaxially, thereby reducing the risk of water vapor penetrating into the motor. The width and depth of the first groove are both greater than those of the second groove, further increasing the radial and axial distances and increasing the resistance to water vapor penetration.

[0012] Preferably, the end cap includes a cover plate, and the cover plate has a first protrusion matching the first groove and a second protrusion matching the second groove on the side near the integral bushing; the length of the first protrusion matches the depth of the first groove, and the length of the second protrusion matches the depth of the second groove.

[0013] By adopting the above technical solution, the first protrusion matches the first groove, and the second protrusion matches the second groove, ensuring normal insertion between the integrated bushing and the end cover; and, since the first groove and the second groove are coaxially set, the first protrusion and the second protrusion are also coaxial, which not only makes the end cover more beautiful, but also enables precise positioning and limiting.

[0014] Preferably, the cover plate is further provided with a third protrusion and a fourth protrusion on the side facing the integrated bushing, and the third protrusion and the fourth protrusion are coaxial with the first protrusion; the outer diameter of the third protrusion is smaller than the inner diameter of the fourth protrusion; the length of the third protrusion is greater than the length of the fourth protrusion; and the length of the fourth protrusion is greater than the length of the first protrusion.

[0015] By adopting the above technical solution, the third and fourth protrusions set coaxially can block the seeping water vapor, reduce the amount of water vapor entering between the integrated bushing and the end cover, and reduce the risk of water vapor seeping into the motor to a certain extent; and the protrusions of different lengths can disperse the stress on the protrusions on the cover plate, so that the forces on each protrusion are not in the same plane, preventing stress concentration that could damage the protrusions.

[0016] Preferably, it also includes a housing, which partially surrounds the rotating shaft, and the end cap is connected to the housing.

[0017] By adopting the above technical solution, the rotating shaft is partially surrounded, which protects the rotating shaft to a certain extent and ensures its normal rotation. The end cover is connected to the housing, keeping the end cover in a relatively stable state. Furthermore, the end cover and the housing together partially surround the rotating shaft, with only a part of the rotating shaft not within the enclosure, thus reducing the risk of the rotating shaft breaking.

[0018] Preferably, a first bearing and a second bearing are provided at both ends of the rotating shaft, with the first bearing located at the end of the rotating shaft closer to the end cover and the second bearing located at the end of the rotating shaft farther from the end cover.

[0019] By adopting the above technical solution, the first and second bearings set at both ends of the rotating shaft support the rotating shaft, ensuring the normal rotation of the rotating shaft.

[0020] Preferably, the substrate has a third groove along the axial direction in the first groove, and the width of the third groove is greater than the width of the first groove; the substrate has a fourth groove along the axial direction in the second groove, and the width of the fourth groove is greater than the width of the second groove; the third groove and the fourth groove are both coaxial with the first groove.

[0021] By adopting the above technical solution, a stepped groove is formed inside the integrated bushing by using the third groove in the first groove and the fourth groove in the second groove, which further extends the path for water vapor to penetrate in, and the stepped groove can enhance the tightness of the connection between the integrated bushing and the end cap.

[0022] Preferably, a fifth protrusion is provided at the end of the first protrusion away from the cover plate, the width of the fifth protrusion being greater than the width of the first protrusion, and the width of the fifth protrusion matching the width of the third groove; a sixth protrusion is provided at the end of the second protrusion away from the cover plate, the width of the sixth protrusion being greater than the width of the second protrusion, and the width of the sixth protrusion matching the width of the fourth groove; a seventh protrusion is provided at the end of the third protrusion away from the cover plate, the width of the seventh protrusion being greater than the width of the third protrusion; and an eighth protrusion is provided at the end of the fourth protrusion away from the cover plate, the width of the eighth protrusion being greater than the width of the fourth protrusion.

[0023] By adopting the above technical solution, the fifth protrusion at the end of the first protrusion is inserted into the third groove, and the sixth protrusion at the end of the second protrusion is inserted into the second groove. The width of the fifth protrusion is greater than the width of the first protrusion, forming a stepped protrusion, which further increases the path for water vapor to penetrate into the motor. At the same time, the stepped insertion structure makes the connection between the integrated bushing and the end cover tighter and also improves the stability of the connection.

[0024] Preferably, the integral bushing is integrally formed and has elasticity.

[0025] By adopting the above technical solution, the flexible and integrally molded bushing is simpler and more convenient to install with the end cap. At the same time, the flexible bushing can also be installed even when the protruding end is large. The entire bushing is integrally molded, which ensures that there is no gap between the boss and the groove, minimizing the possibility of water vapor penetration.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. By utilizing several protrusions and grooves that match each other between the integrated bushing and the end cover, the radial distance is extended, increasing the path for moisture to enter the motor. The grease filling the space between the integrated bushing and the end cover fills the tiny gap between them. The grease also has strong hydrophobicity, which increases the motor's water resistance. 2. The integrated bushing combines the bushing and the gasket into one piece, ensuring that there is no gap between the boss and the groove, minimizing the possibility of water vapor penetration. Attached Figure Description

[0027] Figure 1This is a schematic diagram of the internal structure of a labyrinth waterproof structure for an electric motor according to this application; Figure 2 yes Figure 1 A magnified view of part A in the middle; Figure 3 This is a perspective view of the integral bushing in a labyrinth waterproof structure for an electric motor according to this application; Figure 4 This is a perspective view of the integral bushing in a labyrinth waterproof structure for an electric motor, as described in this application. Figure 5 This is a structural diagram of the internal structure of the motor in Example 2; Figure 6 yes Figure 5 A magnified view of part B in the middle section.

[0028] Explanation of reference numerals in the attached figures: 1. Shaft; 2. End cap; 20. Cover plate; 21. First protrusion; 22. Second protrusion; 23. Third protrusion; 24. Fourth protrusion; 25. Fifth protrusion; 26. Sixth protrusion; 27. Seventh protrusion; 28. Eighth protrusion; 3. Integrated bushing; 31. Base plate; 32. First boss; 33. Second boss; 300. First through hole; 301. First groove; 302. Second groove; 303. Third groove; 304. Fourth groove; 4. Housing; 5. First bearing; 6. Second bearing. Detailed Implementation

[0029] The following is in conjunction with the appendix Figure 1 - Appendix Figure 6 This application will be described in further detail.

[0030] This application discloses a labyrinth waterproof structure for electric motors.

[0031] Example 1: Reference Figure 1 A labyrinth waterproof structure for an electric motor includes a shaft 1, an end cap 2, an integral bushing 3, a housing 4, a first bearing 5, and a second bearing 6. The shaft 1 passes through the first bearing 5 and the second bearing 6. The end cap 2 is connected to the housing 4. The integral bushing 3 is sleeved on the shaft 1. The first bearing 5 is located at the output end of the shaft 1. The second bearing 6 is located at the end of the shaft 1 away from the end cap 2. The first bearing 5 and the second bearing 6 respectively support the two ends of the shaft 1, and the first bearing 5 and the second bearing 6 restrict the position of the shaft 1 to prevent the shaft 1 from shifting when rotating.

[0032] Reference Figure 2 The integrated bushing 3 includes a base plate 31, a first boss 32, a second boss 33, a first groove 301, and a second groove 302; the first boss 32 and the second boss 33 are respectively disposed on opposite sides of the base plate 31, and the first boss 32 is disposed on the side of the base plate 31 near the axis of the rotating shaft 1; the base plate 31 has a first groove 301 and a second groove 302, both of which are annular and coaxial.

[0033] Reference Figure 3 The integral bushing 3 is generally disc-shaped. A first through hole 300 is provided in the middle of the integral bushing 3. The first through hole 300 penetrates the substrate 31 and the first boss 32. The first boss 32 extends from one side of the substrate 31 along the axial direction. The first groove 301, the second groove 302 and the first boss 32 are located on the same side of the substrate 31.

[0034] Reference Figure 4 The substrate 31 has a second protrusion 33 on the side opposite to the first protrusion 32. The second protrusion 33 is coaxial with the first through hole 300, and the first through hole 300 passes through the second protrusion 33.

[0035] Reference Figure 2 The end cap 2 is provided with a first protrusion 21 and a second protrusion 22 on the side near the integrated bushing 3. The first protrusion 21 is inserted into the first groove 301, and the second protrusion 22 is inserted into the second groove 302. The space between the first protrusion 21 and the first groove 301 is filled with grease (not shown in the figure). The position where the side of the first boss 32 contacts the end cap 2 is also filled with grease, and the area coated with grease extends from the side of the first boss 32 into the first groove 301.

[0036] In this embodiment, the amount of grease should completely fill the gap between the integrated bushing 3 and the end cap 2. Sufficient grease can be applied to the surfaces of the first groove 301 and the first boss 32. If the grease overflows into the second groove 302 during insertion, it indicates that the amount of grease is sufficient.

[0037] Reference Figure 2The end cap 2 also includes a third protrusion 23 and a fourth protrusion 24. The height of the third protrusion 23 is greater than the height of the fourth protrusion 24, and the thickness of the third protrusion 23 is greater than the thickness of the substrate 31. In other words, the third protrusion 23 blocks the substrate 31 and at least a portion of the second protrusion 33. Thus, when water vapor penetrates in, the third protrusion 23 can block most of the water vapor, reducing the amount of water vapor that penetrates into the gap between the integrated bushing 3 and the end cap 2, thereby increasing the waterproofness of the motor to a certain extent.

[0038] In this embodiment, the integrated bushing 3 does not have grooves matching the third protrusion 23 and the fourth protrusion 24. The third protrusion 23 and the fourth protrusion 24 do not serve a sealing function. The third protrusion 23 and the fourth protrusion 24 are used to block water vapor, and a labyrinth structure is formed between the third protrusion 23 and the fourth protrusion 24. When water vapor penetrates in, at least a portion of it is blocked or enters the labyrinth structure, reducing the probability of water vapor penetrating into the motor.

[0039] The implementation principle of Example 1 is as follows: The components inside the motor, including the first bearing 5, the second bearing 6, the rotating shaft 1, and the housing 4, are installed in a specific order. Then, the end cap 2 is fitted onto the rotating shaft 1 and secured to the housing 4. Next, grease is applied to the side of the first protrusion 32 of the integrated bushing 3, extending the grease coating from the side of the first protrusion 32 into the first groove 301, ensuring sufficient grease on the surface of the integrated bushing 3. Then, the side of the integrated bushing 3 with the first protrusion 32 faces the end cap 2, and the first protrusion 21 is aligned with the first groove 301, and the second protrusion 22 is aligned with the second groove 302. The integrated bushing 3 is then inserted into and pressed firmly onto the end cap 2, ensuring tight contact between the integrated bushing 3 and the end cap 2. Finally, the motor is turned on, and the rotation of the rotating shaft 1 is measured, completing the installation.

[0040] Example 2: The difference between this embodiment and Embodiment 1 is that, in this embodiment, the end of the first protrusion 21 is provided with a fifth protrusion 25 with a larger width, the end of the second protrusion 22 is provided with a sixth protrusion 26 with a larger width, the end of the third protrusion 23 is provided with a seventh protrusion 27 with a larger width, the end of the fourth protrusion 24 is provided with an eighth protrusion 28 with a larger width, the first groove 301 has a third groove 303 with a larger width, and the second groove has a fourth groove 304 with a larger width, forming a connection structure with certain limitations, further increasing the path for water vapor to penetrate into the motor and reducing the risk of water vapor penetrating into the motor.

[0041] Reference Figure 5The integrated bushing 3 and the end cap 2 are both fitted onto the rotating shaft 1.

[0042] Reference Figure 6 The substrate 31 has a third groove 303 in the first groove 301 along the axial direction. The width of the third groove 303 is greater than the width of the first groove 301. The first groove 301 and the third groove 303 are in communication.

[0043] Reference Figure 6 The substrate 31 has a fourth groove 304 in the second groove 302 along the axial direction. The width of the fourth groove 304 is greater than the width of the second groove 302. The second groove 302 is connected to the fourth groove 304. The third groove 303 and the fourth groove 304 are both concentric with the first groove 301.

[0044] Reference Figure 6 A fifth protrusion 25 is provided at the end of the first protrusion 21 away from the cover plate 20. The width of the fifth protrusion 25 is greater than the width of the first protrusion 21. The width of the fifth protrusion 25 matches the width of the third groove 303. The fifth protrusion 25 and the third groove 303 are inserted into each other.

[0045] Reference Figure 6 The second protrusion 22 is provided with a sixth protrusion 26 at the end away from the cover plate 20. The width of the sixth protrusion 26 is greater than the width of the second protrusion 22. The width of the sixth protrusion 26 matches the width of the fourth groove 304. The sixth protrusion 26 and the fourth groove 304 are inserted into each other.

[0046] Reference Figure 6 The third protrusion 23 has a seventh protrusion 27 at the end away from the cover plate 20, and the width of the seventh protrusion 27 is greater than the width of the third protrusion 23; the fourth protrusion 24 has an eighth protrusion 28 at the end away from the cover plate 20, and the width of the eighth protrusion 28 is greater than the width of the fourth protrusion 24.

[0047] In this embodiment, the cross-section of the entire protrusion formed by the first protrusion 21 and the fifth protrusion 25 is similar to an inverted "T" shape, forming a stepped structure that cooperates with the first groove 301 and the third groove 303. After the first protrusion 21 and the second groove 302 are inserted, the fifth protrusion 25 and the third groove 303 also cooperate to be inserted. The stepped structure restricts the connection between the connecting bushing 3 and the end cap 2, which to a certain extent increases the compactness between the connecting bushing 3 and the end cap 2.

[0048] In this embodiment, the integrated bushing 3 is made of a material with a certain elasticity, such as rubber, which does not affect the fit between the integrated bushing 3 and the end cap 2. Furthermore, the lengths of the first boss 32 and the second boss 33 should be appropriately increased so that the integrated bushing 3 is not affected when compressed.

[0049] In this embodiment, when selecting the material of the integrated bushing 3, attention should be paid to selecting a material with strong chemical stability to ensure that the integrated bushing 3 does not produce a chemical reaction with the grease. For example, avoid using fluorosilicone rubber in combination with silicone oil to prevent swelling problems.

[0050] In this embodiment, by adding the fifth protrusion 25, the sixth protrusion 26, the seventh protrusion 27 and the eighth protrusion 28, the path for water vapor to penetrate into the motor is further extended; in other embodiments of this application, the extension direction and shape of the protrusions can be changed, such as setting two protrusions at the inner and outer diameters of the first protrusion 21 along the axial direction to form an inverted "C" shaped insertion protrusion.

[0051] The implementation principle of Example 2 is as follows: The components inside the motor, including the first bearing 5, the second bearing 6, the shaft 1, and the housing 4, are installed in a specific order. Then, the end cap 2 is fitted onto the shaft 1 and secured to the housing 4. Next, grease is applied to the side of the first protrusion 32 of the integrated bushing 3, extending the grease coating from the side of the first protrusion 32 into the first groove 301, ensuring sufficient grease on the surface of the integrated bushing 3. Then, the side of the integrated bushing 3 with the first protrusion 32 faces the end cap 2, and the first protrusion 21 is aligned with the first groove 301, the second protrusion 22 with the second groove 302, the fifth protrusion 25 with the third groove 303, and the sixth protrusion 26 with the fourth groove 304, thereby inserting and pressing the integrated bushing 3 into the end cap 2, ensuring tight contact between the integrated bushing 3 and the end cap 2. Finally, the motor is turned on, and the rotation of the shaft 1 is tested, completing the installation.

[0052] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A labyrinth waterproof structure for an electric motor, characterized in that: It includes a rotating shaft (1), an end cap (2), and an integrated bushing (3); The end cap (2) and the integrated bushing (3) are both sleeved on the output end of the rotating shaft (1), and at least a portion of the integrated bushing (3) is in contact with the end cap (2); The integrated bushing (3) has several protrusions and several grooves on the side near the end cap (2), and the end cap (2) has grooves and protrusions that match the integrated bushing (3) on the side near the integrated bushing (3). The integral bushing (3) and the end cap (2) are connected by several protrusions and several grooves, and the connection between the integral bushing (3) and the end cap (2) is filled with grease.

2. The labyrinth waterproof structure for an electric motor according to claim 1, characterized in that: The integrated bushing (3) includes a base plate (31), and a first through hole (300) for the rotating shaft (1) to pass through is opened in the middle of the base plate (31). The diameter of the first through hole (300) matches the diameter of the rotating shaft (1). The substrate (31) has a first boss (32) along the axial direction on the side near the end cap (2), and the first boss (32) is coaxial with the first through hole (300); The substrate (31) has a second boss (33) on the side away from the end cap (2) along the axial direction, and the second boss (33) is coaxial with the first through hole (300).

3. The labyrinth waterproof structure for an electric motor according to claim 2, characterized in that: The substrate (31) has a first groove (301) and a second groove (302) arranged coaxially on the side near the end cap (2). The outer diameter of the first groove (301) is smaller than the inner diameter of the second groove (302); The depth of the first groove (301) is greater than the depth of the second groove (302); the width of the first groove (301) is greater than the width of the second groove (302).

4. The labyrinth waterproof structure for an electric motor according to claim 3, characterized in that: The end cap (2) includes a cover plate (20), and the cover plate (20) has a first protrusion (21) matching the first groove (301) and a second protrusion (22) matching the second groove (302) on the side near the integrated bushing (3). The length of the first protrusion (21) matches the depth of the first groove (301), and the length of the second protrusion (22) matches the depth of the second groove (302).

5. A labyrinth waterproof structure for an electric motor according to claim 4, characterized in that: The cover plate (20) is provided with a third protrusion (23) and a fourth protrusion (24) on the side facing the integrated bushing (3), and the third protrusion (23) and the fourth protrusion (24) are coaxial with the first protrusion (21); The outer diameter of the third protrusion (23) is smaller than the inner diameter of the fourth protrusion (24); the length of the third protrusion (23) is greater than the length of the fourth protrusion (24); The length of the fourth protrusion (24) is greater than the length of the first protrusion (21).

6. The labyrinth waterproof structure for an electric motor according to claim 1, characterized in that: It also includes a housing (4), which partially surrounds the rotating shaft (1), and the end cap (2) is connected to the housing (4).

7. A labyrinth waterproof structure for an electric motor according to claim 1, characterized in that: The rotating shaft (1) is provided with a first bearing (5) and a second bearing (6) at both ends. The first bearing (5) is located at the end of the rotating shaft (1) near the end cover (2), and the second bearing (6) is located at the end of the rotating shaft (1) away from the end cover (2).

8. A labyrinth waterproof structure for an electric motor according to claim 5, characterized in that: The substrate (31) has a third groove (303) in the first groove (301) along the axial direction, and the width of the third groove (303) is greater than the width of the first groove (301). The substrate (31) has a fourth groove (304) in the second groove (302) along the axial direction, and the width of the fourth groove (304) is greater than the width of the second groove (302); The third groove (303) and the fourth groove (304) are both coaxial with the first groove (301).

9. A labyrinth waterproof structure for an electric motor according to claim 8, characterized in that: A fifth protrusion (25) is provided at one end of the first protrusion (21) away from the cover plate (20). The width of the fifth protrusion (25) is greater than the width of the first protrusion (21), and the width of the fifth protrusion (25) matches the width of the third groove (303). The second protrusion (22) has a sixth protrusion (26) at one end away from the cover plate (20). The width of the sixth protrusion (26) is greater than the width of the second protrusion (22), and the width of the sixth protrusion (26) matches the width of the fourth groove (304). The third protrusion (23) has a seventh protrusion (27) at the end away from the cover plate (20), and the width of the seventh protrusion (27) is greater than the width of the third protrusion (23); The fourth protrusion (24) has an eighth protrusion (28) at the end away from the cover plate (20), and the width of the eighth protrusion (28) is greater than the width of the fourth protrusion (24).

10. A labyrinth waterproof structure for an electric motor according to claim 1, characterized in that: The integral bushing (3) is integrally formed and has elasticity.

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