Conductive shaft end sealing device

Abstract

The invention relates to a conductive shaft end sealing device, and belongs to the field of new energy driving systems, the conductive shaft end sealing device comprises an electric conductor and a sealing body, the electric conductor and the sealing body are in contact and relatively fixed, one side of the electric conductor is in contact with the side wall of a rotating shaft, the other side of the electric conductor is in contact with a bearing seat, and the sealing body is in contact with the side wall of the rotating shaft. The sealing body is responsible for oil sealing, the electric conductor is responsible for transmitting current between the rotating shaft and the bearing seat, current output of the rotating shaft to the bearing is reduced, and therefore electric corrosion damage of the bearing is reduced.

Description

Technical Field

[0001] The present application relates to the field of new energy drive systems, and in particular to a conductive shaft end sealing device. Background Art

[0002] In the field of new energy drive, automotive electric drive systems with high-voltage inverters as the core have become the mainstream technical route. As a result, high voltage, high frequency and high rotation speed have caused the problem of bearing electrical corrosion. Bearing electrical corrosion is due to the potential difference between the two ends of the shaft or between the shaft and the bearing when the motor is running, which forms a current. The current is discharged through the lubricating oil film in the bearing, causing local heat melting and bumps.

[0003] In order to solve the problem of electrical corrosion of bearings, ceramic bearings are used. The outer diameter of the ceramic bearing abuts the bearing seat, and the inner diameter abuts the side wall of the shaft, providing high-strength and insulated rotation support for the shaft, which will lead to a significant increase in costs.

[0004] With respect to the above-mentioned related technologies, the inventor believes that there are the following defects. Summary of the invention

[0005] In order to improve the above problems, the present application provides a conductive shaft end sealing device.

[0006] The conductive shaft end sealing device provided in this application adopts the following technical solution: A conductive shaft end sealing device comprises a conductor and a sealing body, wherein the conductor and the sealing body are in contact and relatively fixed, one side of the conductor is in contact with the side wall of the rotating shaft, and the other side is in contact with the bearing seat, and the sealing body is in contact with the side wall of the rotating shaft.

[0007] By adopting the above technical solution, the sealing device is located close to the bearing, the sealing body is responsible for oil sealing, and the conductor is responsible for transmitting current between the rotating shaft and the bearing seat, reducing the current output of the rotating shaft to the bearing, thereby reducing the electrical corrosion damage of the bearing.

[0008] Preferably, the conductor includes a conductive ring shell and a conductive contact ring piece, the conductive ring shell and the conductive contact ring piece are coaxially fixedly connected, the conductive ring shell is in contact with the bearing seat, the conductive contact ring piece is in contact with the side wall of the rotating shaft, and the hardness of the conductive ring shell is greater than the hardness of the conductive contact ring piece.

[0009] By adopting the above technical solution, due to the continuous movement of the shaft, the conductive contact ring piece in direct contact with the shaft is made of a material with relatively low hardness, thereby reducing the magnitude of the hard friction force on the side wall of the shaft and reducing structural damage to the shaft and the conductor.

[0010] Preferably, the inner side of the conductive contact ring sheet is bent toward the direction in which the rotating shaft penetrates to form a bent portion, the bent portion abuts against the side wall of the rotating shaft, and a force-reducing notch is provided on the bent portion.

[0011] By adopting the above technical solution, the existence of the force-reducing notch enables the inner bending portion of the conductive contact ring piece to have a more sensitive deformation ability, reduces the holding force of the conductive contact ring piece on the rotating shaft, reduces wear, and prolongs the retention time of the conductive path.

[0012] Preferably, a mounting groove is formed on the inner edge of the conductive ring shell, the sealing body is located in the mounting groove, the outer edge of the sealing body abuts against the bottom of the mounting groove, and the inner edge of the sealing body abuts against the side wall of the rotating shaft.

[0013] By adopting the above technical solution, the conductive ring shell itself is used as a part of the conductor to conduct the circuit, and the mounting ring groove provides a mounting position and space for the seal, thereby improving the coaxial installation stability of the conductor and the seal.

[0014] Preferably, the sealing body comprises a rubber ring body and a supporting skeleton ring, the supporting skeleton ring is coaxially embedded in the rubber ring body, the rubber ring body is provided with an embedding groove for embedding the supporting skeleton ring, and the rubber ring body is in contact with the conductive ring shell and the side wall of the rotating shaft at the same time.

[0015] By adopting the above technical solution, the supporting skeleton ring is located inside the rubber ring body to provide structural support to the rubber ring body, thereby improving the structural stability of the rubber ring body.

[0016] Preferably, one side of the rubber ring body abuts against the conductive contact ring sheet, the side of the conductive contact ring sheet facing away from the rubber ring body abuts against the groove wall of the mounting ring groove, and the side of the rubber ring body facing the conductive contact ring sheet is integrally formed with a friction edge.

[0017] By adopting the above technical solution, the friction edge is used to increase the friction between the rubber ring body and the conductive contact ring piece, thereby improving the relative stability between the two.

[0018] Preferably, the sealing body further comprises a supporting ring, a matching ring groove is coaxially provided on the rubber ring body, the supporting ring is embedded in the matching ring groove, and the supporting ring and the side wall of the rotating shaft simultaneously form abutting force on the rubber ring body.

[0019] By adopting the above technical solution, the supporting ring imprisons the outer ring of the rubber ring body abutting the rotating shaft, weakening the outward turning ability of this part of the rubber ring body, thereby further improving the stability of the rubber ring body abutting the rotating shaft.

[0020] Preferably, the outer diameter of the support skeleton ring is larger than the inner diameter of the conductive ring shell, the support skeleton ring comprises a plurality of unit blocks and connectors, the plurality of unit blocks are arranged in a circular array around the axis of the rotating shaft, and the connectors are used to relatively fix all the unit blocks.

[0021] By adopting the above technical solution, the installation stability of the sealing body on the conductive ring shell is higher, and the support skeleton ring is divided into multiple unit bodies to facilitate the unit blocks to enter the installation ring groove for assembly.

[0022] Preferably, the connecting member is a connecting ring, a connecting hole is opened on the unit block, a plurality of docking pins are fixedly connected to the connecting ring, a single connecting hole is for inserting a docking pin, an expansion protrusion is integrally formed on the end of the docking pin, and the expansion protrusion abuts against the hole wall of the connecting hole.

[0023] By adopting the above technical solution, when the connecting ring abuts against each unit block, the expansion protrusion abuts against the hole wall of the connecting hole. The friction between the expansion protrusion and the hole wall of the connecting hole prevents the connecting ring from easily detaching from the unit blocks, and the supporting skeleton ring has a higher morphological stability.

[0024] Preferably, a negative pressure ring groove is coaxially provided on one side of the rubber ring body facing the conductive contact ring piece, the conductive contact ring piece closes the notch of the negative pressure ring groove, an air pressure slit hole is provided on the rubber ring body, one end of the air pressure slit hole is located at the bottom of the negative pressure ring groove, and the other end is located at the bottom of the embedding groove, a clearance hole is provided on the support skeleton ring, and a packaging hole is provided on the connecting ring, the air pressure slit hole, the clearance hole and the packaging hole are aligned, a sealing plug is inserted on the connecting ring through the packaging hole, and the sealing plug abuts against the rubber ring body.

[0025] By adopting the above technical solution, the sealing plug is inserted when the negative pressure ring groove is in a state of spatial contraction. After the sealing plug seals the packaging hole, the force applied to the sealing body is released. The negative pressure state in the negative pressure ring groove makes the abutment relationship between the rubber ring body and the conductive contact ring piece closer.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. Through the arrangement of the conductor and the seal, the sealing device is located close to the bearing. The seal is responsible for oil sealing, and the conductor is responsible for transmitting current between the shaft and the bearing seat, thereby reducing the current output of the shaft to the bearing, thereby reducing the electrical corrosion damage of the bearing; 2. By providing a conductive ring shell with a mounting ring groove, the conductive ring shell itself is used as a part of the conductor to conduct the circuit. At the same time, the mounting ring groove provides an installation position and space for the seal, thereby improving the coaxial installation stability of the conductor and the seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic cross-sectional view of the structure of the conductive shaft end sealing device in the first embodiment of the present application.

[0028] Figure 2 It is a structural stereoscopic schematic diagram used to embody the conductive shaft end sealing device in the first embodiment of the present application.

[0029] Figure 3 It is a schematic cross-sectional view of the structure of the conductive shaft end sealing device used to embody the second embodiment of the present application.

[0030] Figure 4 It is a schematic diagram of the structural explosion of the sealing body in the second embodiment of the present application.

[0031] Explanation of the reference numerals: 1. rotating shaft; 11. bearing seat; 2. conductor; 21. conductive ring shell; 211. mounting ring groove; 22. conductive contact ring piece; 221. bending portion; 222. force reduction notch; 3. sealing body; 31. rubber ring body; 311. embedding groove; 312. friction edge; 313. negative pressure ring groove; 314. air pressure slit hole; 32. supporting skeleton ring; 321. unit block; 322. connecting hole; 323. giving way hole; 3231. semicircular hole; 324. connecting ring; 325. docking pin; 3251. expansion bulge; 326. packaging hole; 327. sealing plug; 33. supporting ring; 34. matching ring groove. DETAILED DESCRIPTION

[0032] The following is combined with Figure 1-4 This application is described in further detail.

[0033] Embodiment 1: The present application embodiment discloses a conductive shaft end sealing device, such as Figure 1 As shown, it includes a conductor 2 and a sealing body 3, both of which are annular and coaxially fixedly connected. The conductor 2 is in contact with the rotating shaft 1 and the bearing seat 11 at the same time, and creates a force-reducing current path between the rotating shaft 1 and the bearing seat 11 through itself; at the same time, the sealing body 3 and the conductor 2 jointly seal the rotating shaft 1 and the bearing seat 11.

[0034] like Figure 1 and 2As shown, the conductor 2 includes a conductive ring shell 21 and a conductive contact ring piece 22. The outer edge of the conductive ring shell 21 abuts against the bearing seat 11, and the two are interference fit; the inner edge of the conductive ring shell 21 is provided with a mounting ring groove 211, and the conductive contact ring piece 22 and the sealing body 3 are both located in the mounting ring groove 211. The conductive contact ring piece 22 contacts and is fixedly connected to one of the groove walls of the mounting ring groove 211, and the conductive contact ring piece 22 and the conductive ring shell 21 are coaxial. The conductive contact ring piece 22 will directly contact the rotating shaft 1, and the hardness and rigidity of the conductive ring shell 21 are greater than those of the conductive contact ring piece 22. The inner side of the conductive contact ring piece 22 is bent toward the direction in which the rotating shaft 1 penetrates to form a bent portion 221, and the bent portion 221 abuts against the side wall of the rotating shaft 1. A plurality of force-reducing notches 222 are provided on the bent portion 221. The existence of the force-reducing notches 222 enables the bent portion 221 on the inner side of the conductive contact ring piece 22 to have a more sensitive deformation ability, thereby reducing the holding force of the conductive contact ring piece 22 on the rotating shaft 1, reducing wear, and extending the holding time of the conductive path. In this embodiment, the conductive ring shell 21 is made of metal, and the conductive contact ring piece 22 is made of conductive PTFE or conductive non-woven fabric.

[0035] like Figure 1 and 2 As shown, the sealing body 3 includes a rubber ring body 31 and a supporting skeleton ring 32. The inner edge of the rubber ring body 31 is sealed against the side wall of the rotating shaft 1, and the outer edge is sealed against the bottom of the mounting ring groove 211; the supporting skeleton ring 32 is coaxially embedded in the rubber ring body 31, and an embedding groove 311 for embedding the supporting skeleton ring 32 is opened on the rubber ring body 31. The cross-section of the supporting skeleton ring 32 is L-shaped and made of SPCC, which is used to improve the structural stability of the rubber ring body 31; the sealing body 3 also includes a supporting ring 33, and a matching ring groove 34 is coaxially opened on the rubber ring body 31. The supporting ring 33 is embedded in the matching ring groove 34, and the supporting ring 33 and the side wall of the rotating shaft 1 simultaneously form a counter-contact force on the rubber ring body 31. In a natural state, the radial dimension of the inner edge of the rubber ring body 31 is smaller than the radial dimension of the shaft 1. When the shaft 1 passes through, the inner edge of the rubber ring body 31 is deformed by the compression force due to its elasticity, and the rubber ring body 31 has a high abutment tightness against the shaft 1. The support ring 33 imprisons the outer ring of the part of the rubber ring body 31 that abuts against the shaft 1, weakening the eversion ability of this part of the rubber ring body 31, thereby further improving the stability of the abutment state of the rubber ring body 31 against the shaft 1.

[0036] like Figure 1 and 2 As shown, one end of the rubber ring body 31 abuts against the conductive contact ring piece 22, and the other end abuts against the other groove wall of the mounting ring groove 211. A friction edge 312 is integrally formed on the side of the rubber ring body 31 facing the conductive contact ring piece 22. The friction edge 312 abuts against the conductive contact ring piece 22. The trajectory of the friction edge 312 is annular and coaxial with the rubber ring body 31.

[0037] Embodiment 2: like Figure 3 and 4 As shown, the outer diameter of the support skeleton ring 32 is larger than the inner diameter of the conductive ring shell 21. In order to facilitate the installation of the sealing body 3 in the conductive ring shell 21, the support skeleton ring 32 includes a connector and six unit blocks 321. The six unit blocks 321 are arranged in a circular array around the axis of the rotating shaft 1. The connector is used to make all the unit blocks 321 relatively fixed. The connecting piece is a connecting ring 324, and each unit block 321 is provided with a connecting hole 322. The axial direction of the connecting hole 322 is parallel to the axial direction of the supporting skeleton ring 32. Six docking pins 325 are fixedly connected to the connecting ring 324. A single connecting hole 322 is for inserting a docking pin 325. An expansion protrusion 3251 is integrally formed on the side wall of the end of the docking pin 325 away from the connecting block. When the docking pin 325 is correspondingly inserted into the connecting hole 322, the expansion protrusion 3251 abuts against the hole wall of the connecting hole 322. When the connecting ring 324 abuts against each unit block 321, the expansion protrusion 3251 is still in abutment with the hole wall of the connecting hole 322. The friction between the expansion protrusion 3251 and the hole wall of the connecting hole 322 makes it impossible for the connecting ring 324 to easily detach from each unit block 321, and the supporting skeleton ring 32 has a high morphological stability.

[0038] like Figure 3 and 4 As shown, each unit block 321 is first embedded in the embedding groove 311, and then the connecting ring 324 is installed. At this time, the connecting ring 324 is located at the notch of the embedding groove 311. A negative pressure ring groove 313 is coaxially opened on the side of the rubber ring body 31 facing the conductive contact ring sheet 22. When the rubber ring body 31 is installed in the installation ring groove 211, the conductive contact ring sheet 22 closes the notch of the negative pressure ring groove 313. At this time, the negative pressure ring groove 313 is a relatively closed annular space; an air pressure slot hole 314 is opened on the rubber ring body 31, one end of the air pressure slot hole 314 is located at the bottom of the negative pressure ring groove 313, and the other end is located at the bottom of the embedding groove 311. There are two air pressure slot holes 314, and the positions of the two air pressure slot holes 314 are first arranged symmetrically with respect to the axis of the rubber ring body 31. Since the material of the rubber ring body 31 is elastic, under the natural state, the air pressure slit hole 314 is in a closed state. When a certain intensity of air pressure is formed between the negative pressure ring groove 313 and the embedding groove 311, the air pressure slit hole 314 can be forced to conduct and allow gas to pass through. That is, when the rubber ring body 31 is pressed to reduce the volume of the negative pressure ring groove 313, the gas in the negative pressure ring groove 313 will overflow to the embedding groove 311 through the air pressure slit hole 314.

[0039] like Figure 3 and 4As shown, two clearance holes 323 are provided on the support skeleton ring 32, and two packaging holes 326 are provided on the connecting ring 324. When the support skeleton ring 32 is located in the embedding groove 311, the air pressure slot hole 314 and the clearance hole 323 can be aligned with the packaging hole 326 one by one. At this time, the support skeleton ring 32 is pressed, and the rubber ring body 31 is also pressurized, and the air pressure in the negative pressure ring groove 313 increases, and the internal gas overflows through the air pressure slot hole 314, the clearance hole 323 and the packaging hole 326, and the space in the negative pressure ring groove 313 is reduced. A sealing plug 327 is inserted through the packaging hole 326 on the connecting ring 324. The sealing plug 327 is made of hard plastic with a certain elasticity. There is friction between the sealing plug 327 and the hole wall of the packaging hole 326, so that it cannot be easily separated from the connecting ring 324; the end of the sealing plug 327 is located at the opening of the air pressure slot hole 314 and abuts against the rubber ring body 31, thereby achieving the sealing of the air pressure slot hole 314. In this embodiment, semicircular holes 3231 are opened on both sides of each unit block 321. One clearance hole 323 is formed by connecting the semicircular holes 3231 of two adjacent unit blocks 321. Therefore, there are six clearance holes 323 in total, and two of them perform the function of the clearance holes 323.

[0040] The implementation principle of a conductive shaft end sealing device in the embodiment of the present application is: The conductive ring shell 21 and the conductive contact ring piece 22 are first installed and fixed, and then the rubber ring body 31 is embedded in the installation ring groove 211, and then each unit block 321 is embedded in the embedding groove 311 one by one. This process requires that two of the finally formed clearance holes 323 and the two air pressure slot holes 314 are aligned one by one. Then the connecting ring 324 is pressed against each unit block 321, the docking pin 325 is inserted into the connecting hole 322, and the sealing plug 327 is inserted when the negative pressure ring groove 313 is in a state of space contraction. After the sealing plug 327 closes the packaging hole 326, the force applied to the sealing body 3 is released, and the negative pressure state in the negative pressure ring groove 313 makes the abutting relationship between the rubber ring body 31 and the conductive contact ring piece 22 tighter.

[0041] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A conductive shaft end sealing device, characterized in that: The invention comprises a conductor (2) and a sealing body (3), wherein the conductor (2) and the sealing body (3) are in contact and relatively fixed, one side of the conductor (2) is in contact with the side wall of the rotating shaft (1), and the other side is in contact with the bearing seat (11), and the sealing body (3) is in contact with the side wall of the rotating shaft (1).

2. A conductive shaft end sealing device according to claim 1, characterized in that: The conductor (2) comprises a conductive ring shell (21) and a conductive contact ring piece (22); the conductive ring shell (21) and the conductive contact ring piece (22) are coaxially fixedly connected; the conductive ring shell (21) is in contact with a bearing seat (11); the conductive contact ring piece (22) is in contact with a side wall of a rotating shaft (1); and the hardness of the conductive ring shell (21) is greater than the hardness of the conductive contact ring piece (22).

3. A conductive shaft end sealing device according to claim 2, characterized in that: The inner side of the conductive contact ring sheet (22) is bent toward the direction in which the rotating shaft (1) penetrates to form a bent portion (221), the bent portion (221) abuts against the side wall of the rotating shaft (1), and a force-reducing notch (222) is provided on the bent portion (221).

4. A conductive shaft end sealing device according to claim 2 or 3, characterized in that: The inner edge of the conductive ring shell (21) is provided with a mounting ring groove (211), the sealing body (3) is located in the mounting ring groove (211), the outer edge of the sealing body (3) abuts against the bottom of the mounting ring groove (211), and the inner edge of the sealing body (3) abuts against the side wall of the rotating shaft (1).

5. A conductive shaft end sealing device according to claim 4, characterized in that: The sealing body (3) comprises a rubber ring body (31) and a supporting skeleton ring (32); the supporting skeleton ring (32) is coaxially embedded in the rubber ring body (31); an embedding groove (311) is provided on the rubber ring body (31) for embedding the supporting skeleton ring (32); and the rubber ring body (31) is in contact with the conductive ring shell (21) and the side wall of the rotating shaft (1) at the same time.

6. A conductive shaft end sealing device according to claim 5, characterized in that: One side of the rubber ring body (31) abuts against the conductive contact ring piece (22), the side of the conductive contact ring piece (22) facing away from the rubber ring body (31) abuts against the groove wall of the mounting ring groove (211), and the side of the rubber ring body (31) facing the conductive contact ring piece (22) is integrally formed with a friction edge (312).

7. A conductive shaft end sealing device according to claim 6, characterized in that: The sealing body (3) further comprises a supporting ring (33), a matching ring groove (34) is coaxially provided on the rubber ring body (31), the supporting ring (33) is embedded in the matching ring groove (34), and the supporting ring (33) and the side wall of the rotating shaft (1) simultaneously form a counter-contact force on the rubber ring body (31).

8. A conductive shaft end sealing device according to claim 6, characterized in that: The outer diameter of the support skeleton ring (32) is greater than the inner diameter of the conductive ring shell (21); the support skeleton ring (32) comprises a plurality of unit blocks (321) and connecting pieces; the plurality of unit blocks (321) are arranged in a ring array around the axis of the rotating shaft (1); and the connecting pieces are used to relatively fix all the unit blocks (321).

9. A conductive shaft end sealing device according to claim 8, characterized in that: The connecting piece is a connecting ring (324), a connecting hole (322) is provided on the unit block (321), a plurality of docking pins (325) are fixedly connected to the connecting ring (324), a single connecting hole (322) is provided for inserting a docking pin (325), an expansion protrusion (3251) is integrally formed at the end of the docking pin (325), and the expansion protrusion (3251) abuts against the hole wall of the connecting hole (322).

10. The conductive shaft end sealing device according to claim 8, characterized in that: A negative pressure ring groove (313) is coaxially provided on one side of the rubber ring body (31) facing the conductive contact ring piece (22), and the conductive contact ring piece (22) closes the notch of the negative pressure ring groove (313). An air pressure slit hole (314) is provided on the rubber ring body (31), one end of the air pressure slit hole (314) is located at the bottom of the negative pressure ring groove (313), and the other end is located at the bottom of the embedding groove (311). A clearance hole (323) is provided on the support skeleton ring (32), and a packaging hole (326) is provided on the connecting ring (324). The air pressure slit hole (314), the clearance hole (323) and the packaging hole (326) are aligned. A sealing plug (327) is inserted through the packaging hole (326) on the connecting ring (324), and the sealing plug (327) is in contact with the rubber ring body (31).

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