Bearing electric corrosion prevention shaft end connecting structure and motor

Abstract

This invention discloses a shaft end connection structure and motor for preventing bearing electro-corrosion. The structure includes an end cover, a rotating shaft, a load-bearing bearing, a conductive bearing, a conductive connection assembly, and a grounding fixing part. The rotating shaft end has a mounting shaft extending outward along its axis. The inner ring of the conductive bearing is fixedly fitted to the outer circumference of the mounting shaft. The diameter of the conductive bearing is smaller than that of the load-bearing bearing. The conductive connection assembly includes an outer sleeve and an insert. The outer sleeve is mounted on the grounding fixing part. The embedded end of the insert is located within the sleeve end of the outer sleeve, and the non-embedded end is securely connected to the outer ring of the conductive bearing. There are at least two inserts, evenly arranged along the circumference of the conductive bearing. Each insert has an elastic element at its embedded end to elastically confine the insert between the conductive bearing and the sleeve end. This structure prevents electro-corrosion of the load-bearing bearing, is less affected by axial and radial movement of the rotor, has high reliability, and is easy to assemble and disassemble. The motor of this invention has the above-mentioned shaft end connection structure and therefore also possesses the above advantages.

Description

Technical Field

[0001] This invention belongs to the field of drive motor technology, specifically relating to a shaft end connection structure and motor that prevents bearing electro-corrosion. Background Technology

[0002] Currently, passenger vehicle motor systems use PWM (Pulse Width Modulation) inverter systems to control motor operation. In a PWM inverter system, the common-mode voltage acts on the motor windings, forming a common-mode current path through the coupling capacitors in the motor. Shaft current is a component of this common-mode current. Excessive shaft current can cause bearing electro-corrosion. When the bearing voltage between the inner and outer raceways rises to a certain level, exceeding the lubricating oil film threshold voltage, a breakdown discharge will occur. The short-circuit current generated by this discharge produces enormous heat in a short time, causing the metal near the breakdown point to melt. This leads to a gradual deterioration in the motor bearing's operating condition, shortening its lifespan. Prolonged shaft current can compromise the reliable operation of the motor. Furthermore, as the DC bus voltage increases, the shaft voltage also increases, further increasing the probability of bearing electro-corrosion.

[0003] Common solutions to this problem include using brushes to allow shaft current to pass through them instead of the bearing. However, brushes are prone to wear and require periodic replacement, which is difficult. Another solution is to use insulated bearings to prevent shaft current from being generated by discharge between the inner and outer rings, but insulated bearings are expensive and not widely adopted. Another approach involves incorporating a small conductive bearing and a conductive spring on the motor rotor. The small conductive bearing is positioned inside the rotor's shaft bore, with its outer ring abutting against the inner wall of the bore. A conductive spring is pressed onto the inner ring of the small conductive bearing, with its other end grounded. This allows the shaft current on the rotor to be diverted and discharged through the small conductive bearing and the spring, reducing the current leaking to the main bearing and preventing galvanic corrosion. However, this solution places stress on only one side of the inner ring of the small conductive bearing, raising concerns about bearing reliability over long-term operation. Therefore, finding a simple and effective solution to prevent galvanic corrosion of load-bearing bearings throughout their lifespan remains a pressing issue. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a shaft end connection structure and motor that is simple in structure, low in cost, and easy to disassemble and maintain to prevent bearing electro-corrosion.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A shaft end connection structure for preventing bearing electro-corrosion includes an end cover, a rotating shaft, a load-bearing bearing, a conductive bearing, a conductive connection assembly, and a grounding fixing part. The rotating shaft is fixed to the end cover by the load-bearing bearing. The end of the rotating shaft has a mounting shaft extending outward along its axis. The inner ring of the conductive bearing is fixedly fitted with the outer circumference of the mounting shaft. The diameter of the conductive bearing is smaller than the diameter of the load-bearing bearing. The conductive connection assembly includes an outer sleeve and an inner insert. The outer sleeve is mounted on the grounding fixing part. The embedded end of the inner insert is located inside the sleeve end of the outer sleeve, and the non-embedded end is tightly connected to the outer ring of the conductive bearing. There are at least two inner inserts, which are evenly arranged along the circumference of the conductive bearing. The embedded end of each inner insert is provided with an elastic element for elastically limiting the inner insert between the conductive bearing and the sleeve end of the outer sleeve.

[0007] Preferably, in the above-mentioned anti-bearing electro-corrosion shaft end connection structure, the sleeve end of the outer sleeve has a constriction structure, the inner insert has a sliding part and a limiting part, the sliding part is inserted into the constriction structure, and the limiting part is used to prevent the inner insert from coming out of the constriction structure.

[0008] Preferably, in the above-mentioned anti-bearing electro-corrosion shaft end connection structure, the closing structure includes a closing shoulder and a closing neck, the outer periphery of the sliding part is fitted with the inner periphery of the closing neck, and the outer periphery of the limiting part is fitted with the inner periphery of the closing shoulder.

[0009] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, the outer sleeve is a tube, the non-sleeving end of the tube has an external thread on its outer circumference, and the grounding fixing part has a threaded hole that mates with the external thread; or, the outer sleeve is a tube, the non-sleeving end of the tube has an internal thread on its inner circumference, the grounding fixing part has a first boss, and the outer circumference of the first boss has an external thread that mates with the internal thread.

[0010] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, the outer kit is a mounting plate, and at least two of the aforementioned closing structures are provided symmetrically on the end face of the mounting plate, each closing structure having an insert and an elastic element that cooperate with it.

[0011] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, the center of the end face of the sleeve end of the mounting plate is provided with an inwardly recessed first mounting groove, the grounding fixing part is provided with a second mounting groove, the center of the second mounting groove is provided with a second boss, the non-sleeve end of the mounting plate is embedded in the second mounting groove, and the bottom of the first mounting groove is in contact with the second boss and fastened by screws.

[0012] In the aforementioned shaft end connection structure for preventing bearing electro-corrosion, preferably, the non-embedded end of the insert abuts against the end face of the outer ring of the conductive bearing.

[0013] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, the insert end of the inner member is provided with a groove for installing the elastic member.

[0014] In the aforementioned shaft end connection structure for preventing bearing electro-corrosion, preferably, the elastic element is a spring.

[0015] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, the elastic element is located between the embedded end of the inner element and the grounding fixing part.

[0016] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, a gasket is provided between the elastic element and the grounding fixing part.

[0017] In the aforementioned anti-bearing electro-corrosion shaft end connection structure, preferably, the grounding fixing part is a junction box cover plate, which is fixed to the outside of the end cover and forms a closed conductive bearing chamber with the end cover.

[0018] As a general technical concept, the present invention also provides an electric motor, including the above-mentioned anti-bearing electro-corrosion shaft end connection structure, wherein the end cover includes a front end cover and a rear end cover, the front end of the rotating shaft extends out of the front end cover, the grounding fixing part is fixed to the outside of the front end cover, and the shaft end structure is located between the front end of the rotating shaft and the grounding fixing part.

[0019] Another implementation of the aforementioned motor is that the end cover includes a front end cover and a rear end cover, the rear end of the rotating shaft extends out of the rear end cover, the grounding fixing part is fixed to the outside of the rear end cover, and the shaft end structure is located between the rear end of the rotating shaft and the grounding fixing part.

[0020] Another implementation of the aforementioned motor is as follows: the end cover includes a front cover and a rear cover; the front end of the rotating shaft extends out of the front cover; the rear end of the rotating shaft extends out of the rear cover; there are two grounding fixing parts, which are respectively installed on the outside of the front cover and the rear cover; and there are two sets of shaft end structures, which are respectively installed on the front end and the rear end of the rotating shaft.

[0021] Explanation of relevant terms in this invention:

[0022] DC bus voltage: The voltage supplied by the battery to the electric drive system in the vehicle.

[0023] Load-bearing bearings: bearings that support the motor rotor to bear the radial and axial loads of the motor.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] (1) The shaft end connection structure of the present invention uses a conductive connection component to directly conduct the shaft current on the rotor to the ground from the end of the shaft. This not only effectively prevents the bearing from electrolytic corrosion, but also ensures that its structure and performance are not affected by the axial and radial movement of the rotor during motor operation, resulting in good robustness. The outer ring of the conductive bearing is subjected to the axial force of two or more uniformly arranged inserts, making the conductive bearing uniformly stressed. Since the insert end is provided with an elastic element, by adjusting the stiffness of the elastic element, the insert applies a certain axial preload to the conductive bearing, which is not a completely rigid stress. Thus, even if the conductive bearing has axial movement during motor operation, it can always maintain good contact with the insert. Furthermore, the nested structure gives the insert a radial clamping force from the outer sleeve, which can overcome the influence of the radial wobble of the conductive bearing during motor operation.

[0026] This invention is the first to use a flexible conductive connection component to contact the outer ring of the conductive bearing to guide the shaft current. The conductive bearing is subjected to uniform force. This solution has a simple structure, few parts, high reliability, low cost, and is very convenient to install and disassemble, making it easy to maintain later.

[0027] (2) The motor of the present invention also has the above-mentioned advantages of the shaft end connection structure because it is equipped with the shaft end connection structure of the present invention. Furthermore, the shaft end connection structure can effectively prevent the bearing from being electro-corroded, thereby improving the operating stability and service life of the motor. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the shaft end connection structure for preventing bearing electro-corrosion according to Embodiment 1 of the present invention.

[0029] Figure 2 This is an exploded three-dimensional structural diagram of the conductive connection component of Embodiment 1 of the present invention.

[0030] Figure 3 This is a schematic diagram of the motor structure of Embodiment 1 of the present invention.

[0031] Figure 4 Schematic diagram of the shaft end connection structure for preventing bearing electro-corrosion in Embodiment 2 of the present invention.

[0032] Figure 5 A schematic diagram of the conductive connection component of Embodiment 2 of the present invention.

[0033] Figure 6 An exploded three-dimensional structural diagram of the conductive connection component of Embodiment 2 of the present invention.

[0034] Figure 7 This is a schematic diagram of the motor structure of Embodiment 2 of the present invention.

[0035] Legend:

[0036] 1. End cap; 11. Front end cap; 12. Rear end cap; 13. Housing; 14. Stator; 15. Rotor; 2. Shaft; 21. Mounting shaft; 3. Bearing bearing; 31. Front bearing bearing; 32. Rear bearing bearing; 4. Conductive bearing; 5. Conductive connection assembly; 50. Closure structure; 501. Closure shoulder; 502. Closure neck; 51. Outer sleeve; 511. First mounting groove; 52. Insert; 521. Sliding part; 522. Limiting part; 6. Elastic element; 7. Grounding fixing part; 71. Second mounting groove; 711. Second boss; 8. Gasket. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0038] Example 1:

[0039] Figures 1 to 3 An embodiment of the shaft end connection structure for preventing bearing electro-corrosion of the present invention is shown, including an end cover 1, a rotating shaft 2, a load bearing 3, a conductive bearing 4, a conductive connection assembly, and a grounding fixing part 7. The rotating shaft 2 is fixed to the end cover 1 by the load bearing 3. The end of the rotating shaft 2 has a mounting shaft 21 extending outward along the axis. The inner ring of the conductive bearing 4 is fixedly fitted with the mounting shaft 21. The diameter of the conductive bearing 4 is smaller than the diameter of the load bearing 3. The conductive connection assembly 5 includes an outer sleeve 51 and an inner insert 52. The outer sleeve 51 is installed on the grounding fixing part 7. The embedded end of the inner insert 52 is located inside the sleeve end of the outer sleeve 51, and the non-embedded end is tightly connected to the outer ring of the conductive bearing 4. There are at least two inner inserts 52, which are evenly arranged along the circumference of the conductive bearing 4. The embedded end of each inner insert 52 is provided with an elastic element 6 for elastically limiting the inner insert 52 between the conductive bearing 4 and the sleeve end of the outer sleeve 51.

[0040] Taking an electric motor as a specific application example, the motor includes a housing 13, a stator 14, a rotor 15, a shaft 2, and an end cover 1. The end cover 1 includes a front cover 11 and a rear cover 12. The front cover 11 and the rear cover 12 are respectively fixed on the housing 13. The two ends of the shaft 2 are respectively mounted on the front cover 11 and the rear cover 12 through two bearings 3. The rotor 15 is fixed on the shaft 2. The stator 14 is located on the outer periphery of the rotor 15. The shaft end connection structure that prevents bearing electro-corrosion is installed at the end of the shaft 2.

[0041] During motor operation, the conductive bearing 4, the front bearing 31, and the rear bearing 32 are all on the rotor 15, forming an equipotential body. The stator 14, housing 13, front cover 11, rear cover 12, grounding fixing part 7, conductive connection assembly 5, and elastic element 6 are connected together, forming another equipotential body. The motor housing 13 is grounded, and its potential is zero. Therefore, the potentials of the conductive bearing 4, the front bearing 31, and the rear bearing 32 relative to ground are equal, meaning their shaft voltages are equal. Because the diameter of the conductive bearing 4 is smaller than that of the front bearing 31 and the rear bearing 32, it is more prone to discharge under the same shaft voltage, i.e., shaft current. The shaft current flows through the conductive bearing 4 to the conductive connection assembly 5, then through the conductive connection assembly 5 to the grounding fixing part 7, and finally to ground. When discharge occurs in the conductive bearing 4, discharge will not occur in the front bearing 31 and the rear bearing 32, thus protecting the front and rear bearings and preventing bearing electrolytic corrosion.

[0042] The conductive insert 52 contacts the outer ring of the conductive bearing 4 in the axial direction. By adjusting the stiffness of the elastic element, the insert 52 applies a certain axial preload to the conductive bearing 4. Thus, even if the conductive bearing 4 experiences axial movement during motor operation, it maintains good contact with the insert 52. Furthermore, there are at least two sets of inserts 52 and corresponding elastic elements 6, evenly distributed to contact the outer ring of the conductive bearing 4, ensuring uniform force distribution on the conductive bearing 4. The nested structure also provides the insert 52 with a radial clamping force from the outer sleeve 51, which overcomes the effects of radial wobble of the conductive bearing 4 during motor operation.

[0043] In this embodiment, the outer sleeve 51 has a closing structure 50 at its socket end, and the inner insert 52 has a sliding portion 521 and a limiting portion 522. The sliding portion 521 passes through the closing structure 50, and the limiting portion 522 is used to prevent the inner insert 52 from coming out of the closing structure 50. The cooperation between the closing structure 50 and the limiting portion 522 can reduce the volume of the inner insert 52 to achieve weight reduction while ensuring the firmness and stability of the assembly.

[0044] In this embodiment, the closing structure 50 includes a closing shoulder 501 and a closing neck 502. The outer periphery of the sliding portion 521 fits against the inner periphery of the closing neck 502, and the outer periphery of the limiting portion 522 fits against the inner periphery of the closing shoulder 501. This strengthens the radial clamping force on the insert 52, which helps to resist the influence of radial wobble of the conductive bearing 4 during motor operation.

[0045] like Figure 2 As shown, the closing structure 50 of this embodiment is in the shape of a short-necked funnel, and the insert 52 is in the shape of a long-necked funnel. The long-necked funnel is stacked in the short-necked funnel, and the long neck of the long-necked funnel (i.e., the sliding part 521) passes through the short neck of the short-necked funnel (i.e., the closing neck 502).

[0046] In this embodiment, the outer sleeve 51 is a sleeve with an external thread structure at the non-sleeving end. A threaded hole that can be matched with it is provided on the grounding fixing part 7, thereby enabling the sleeve to be detachably installed on the grounding fixing part 7. This reduces the number of parts and makes disassembly and assembly convenient.

[0047] In this embodiment, the non-embedded end of the insert 52 abuts against the end face of the outer ring of the conductive bearing 4, facilitating disassembly and assembly. Since the radial runout of the shaft is limited by the radial clearance of the bearing, it is usually within 0.1mm. As long as the distance between the position of the insert and the inner and outer rings of the conductive bearing end face is greater than 0.2mm, good contact between the insert and the conductive bearing can be ensured, achieving stable grounding.

[0048] In this embodiment, the insert 52 has a groove at its insertion end for mounting the elastic member 6. This groove facilitates accurate and rapid positioning and mounting of the elastic member. Of course, when the diameter of the elastic member 6 is comparable to the inner diameter of the outer sleeve 51, the insert 52 can mount the elastic member 6 well without the groove.

[0049] In this embodiment, the elastic element 6 is located between the embedded end of the insert 52 and the grounding fixing part 7. In other embodiments, depending on the actual length of the required elastic element 6, the elastic element 6 may also be installed on the bottom end of the outer sleeve 51 or on an internal mounting component.

[0050] In this embodiment, the elastic element 6 is a spring, and a washer 8 is provided between the spring and the grounding fixing part 7 so that the spring presses on the washer 8, making the spring stable and not tilted.

[0051] In this embodiment, the grounding fixing part 7 is a junction box cover plate. The junction box cover plate is fixed on the outside of the end cover 1 and forms a closed conductive bearing chamber with the end cover 1. The space is independent. During installation and disassembly, it is only necessary to remove the junction box cover plate. The structure is simple and the disassembly and assembly are very convenient.

[0052] In this embodiment, the shaft end connection structure for preventing bearing electro-corrosion involves first interfering with the inner ring of the conductive bearing 4 and the outer circumference of the mounting shaft 21 extending from the rear end cover 12 during installation. The conductive bearing 4 is a deep groove ball bearing with dust covers on both sides. The conductive insert 52 is assembled inside the outer sleeve 51, so that the limiting part 522 of the insert 52 fits against the shoulder 501, and the sliding part 521 fits against the neck 502 and passes through it. Then, the spring is assembled on the embedded end of the insert 52. The non-sleeving end of the outer sleeve 51 is screwed to the junction box cover plate. Finally, the junction box cover plate is fixed to the rear end cover 12 with screws.

[0053] A type of motor, such as Figure 3As shown, the shaft end connection structure for preventing bearing electro-corrosion in this embodiment includes the end cover 1, which includes a front cover 11 and a rear cover 12. The rear end of the rotating shaft 2 extends out of the rear cover 12. The junction box cover is fixed to the outside of the rear cover 12. The shaft end structure is located between the rear end of the rotating shaft 2 and the junction box cover.

[0054] The motor of the present invention has the advantages of the shaft end connection structure because it is equipped with a shaft end connection structure that prevents bearing electro-corrosion. Furthermore, the shaft end connection structure can effectively prevent bearing electro-corrosion of the bearing 3, thereby improving the operating stability and service life of the motor.

[0055] In other embodiments, the shaft end connection structure for preventing bearing electro-corrosion can also be set at the front end of the rotating shaft 2. Specifically, the front end of the rotating shaft 2 extends out of the front end cover 11, the junction box cover is fixed on the outside of the front end cover 11, and the shaft end connection structure is located between the front end of the rotating shaft 2 and the junction box cover.

[0056] In other embodiments, anti-bearing electro-corrosion shaft end connection structures can also be provided at both the front and rear ends of the rotating shaft 2.

[0057] Example 2:

[0058] Figures 4 to 7 An embodiment of the shaft end connection structure for preventing bearing electro-corrosion of the present invention is shown, including an end cover 1, a rotating shaft 2, a bearing 3, a conductive bearing 4, a conductive connection assembly 5, and a grounding fixing part 7. The rotating shaft 2 is fixed to the end cover 1 by the bearing 3. The end of the rotating shaft 2 has a mounting shaft 21 extending outward along the axis. The inner ring of the conductive bearing 4 is fixedly fitted with the mounting shaft 21. The diameter of the conductive bearing 4 is smaller than the diameter of the bearing 3. The conductive connection assembly 5 includes an outer sleeve 51 and an inner insert 52. The outer sleeve 51 is installed on the grounding fixing part 7. The embedded end of the inner insert 52 is located inside the sleeve end of the outer sleeve 51, and the non-embedded end is tightly connected to the outer ring of the conductive bearing 4. There are at least two inner inserts 52, which are evenly arranged along the circumference of the conductive bearing 4. Each inner insert 52 has an elastic element 6 at its embedded end, which is used to elastically limit the inner insert 52 between the conductive bearing 4 and the sleeve end of the outer sleeve 51.

[0059] Taking an electric motor as a specific application example, the motor includes a housing 13, a stator 14, a rotor 15, a shaft 2, and an end cover 1. The end cover 1 includes a front cover 11 and a rear cover 12. The front cover 11 and the rear cover 12 are respectively fixed on the housing 13. The two ends of the shaft 2 are respectively mounted on the front cover 11 and the rear cover 12 through two bearings 3. The rotor 15 is fixed on the shaft 2. The stator 14 is located on the outer periphery of the rotor 15. The shaft end connection structure that prevents bearing electro-corrosion is installed at the end of the shaft 2.

[0060] During motor operation, the conductive bearing 4, the front bearing 31, and the rear bearing 32 are all on the rotor 15, forming an equipotential body. The stator 14, housing 13, front cover 11, rear cover 12, grounding fixing part 7, conductive connection assembly 5, and elastic element 6 are connected together, forming another equipotential body. The motor housing 13 is grounded, and its potential is zero. Therefore, the potentials of the conductive bearing 4, front bearing 31, and rear bearing 32 relative to ground are equal, meaning their shaft voltages are equal. Because the diameter of the conductive bearing 4 is smaller than that of the front bearing 31 and rear bearing 32, it is more prone to discharge under the same shaft voltage, i.e., shaft current. The shaft current flows through the conductive bearing 4 to the conductive connection assembly, then through the conductive connection assembly to the grounding fixing part 7, and finally to ground. When discharge occurs in the conductive bearing 4, discharge will not occur in the front bearing 31 and rear bearing 32, thus protecting the front and rear bearings and preventing bearing electrolytic corrosion.

[0061] The conductive insert 52 contacts the outer ring of the conductive bearing 4 in the axial direction. By adjusting the stiffness of the elastic element, the insert 52 applies a certain axial preload to the conductive bearing 4. In this way, even if the conductive bearing 4 has axial movement during motor operation, it can always maintain good contact with the insert 52. Moreover, there are at least two sets of insert 52 and corresponding elastic elements 6, which are evenly arranged to contact the outer ring of the conductive bearing 4, so that the conductive bearing 4 is subjected to uniform force.

[0062] In this embodiment, the outer sleeve 51 has a closing structure 50 at its socket end, and the inner insert 52 has a sliding portion 521 and a limiting portion 522. The sliding portion 521 passes through the closing structure 50, and the limiting portion 522 is used to prevent the inner insert 52 from coming out of the closing structure 50. The cooperation between the closing structure 50 and the limiting portion 522 can reduce the volume of the inner insert 52 to achieve weight reduction while ensuring the firmness of the assembly.

[0063] In this embodiment, the closing structure 50 includes a closing shoulder 501 and a closing neck 502. The outer periphery of the sliding portion 521 fits against the inner periphery of the closing neck 502, and the outer periphery of the limiting portion 522 fits against the inner periphery of the closing shoulder 501. This strengthens the radial force on the insert 52, which helps to resist the influence of radial wobble of the conductive bearing 4 during motor operation.

[0064] like Figure 4 , Figure 5 , Figure 6 As shown, in this embodiment, the outer sleeve 51 is a mounting plate. At least two closing structures 50 are provided symmetrically on the end face of the socket end of the mounting plate. Each closing structure 50 has an insert 52 and an elastic member 6 that cooperate with it.

[0065] In this embodiment, the center of the end face of the socket end of the mounting plate is provided with an inwardly recessed first mounting groove 511, the grounding fixing part 7 is provided with a second mounting groove 71, the center of the second mounting groove 71 is provided with a second boss 711, the non-socket end of the mounting plate is embedded in the second mounting groove 71, the bottom of the first mounting groove 511 is attached to the second boss 711 and fastened by screws.

[0066] In this embodiment, the non-embedded end of the insert 52 abuts against the end face of the outer ring of the conductive bearing 4.

[0067] In this embodiment, the insert 52 has a groove at its insertion end for installing the elastic member 6, which facilitates accurate and rapid positioning and installation of the elastic member.

[0068] In this embodiment, the elastic element 6 is located between the embedded end of the insert 52 and the grounding fixing part 7.

[0069] In this embodiment, the grounding fixing part 7 is a junction box cover plate. The junction box cover plate is fixed on the outside of the end cover 1 and forms a closed conductive bearing chamber with the end cover 1. The space is independent. During installation and disassembly, it is only necessary to remove the junction box cover plate. The structure is simple and the disassembly and assembly are very convenient.

[0070] In this embodiment, the shaft end connection structure for preventing bearing electro-corrosion involves first interfering with the outer circumference of the mounting shaft 21 extending from the rear end cover 12 by fitting the inner ring of the conductive bearing 4 with a dust cover on both sides. The conductive bearing 4 is a deep groove ball bearing. The conductive insert 52 is then assembled inside the outer sleeve, with the limiting part 522 of the insert 52 fitting against the shoulder 501 and the sliding part 521 fitting against and passing through the neck 502. A spring is then assembled into the embedded end of the insert 52. The non-sleeving end of the outer sleeve 51, i.e., the mounting plate, is then embedded into the second mounting groove 71, with the bottom of the first mounting groove 511 fitting against the second boss 711 in the second mounting groove 71 and secured with screws. Finally, the junction box cover is fixed to the rear end cover 12 with screws.

[0071] A type of motor, such as Figure 7 As shown, the shaft end connection structure for preventing bearing electro-corrosion in this embodiment includes the end cover 1, which includes a front cover 11 and a rear cover 12. The rear end of the rotating shaft 2 extends out of the rear cover 12. The junction box cover is fixed to the outside of the rear cover 12. The shaft end structure is located between the rear end of the rotating shaft 2 and the junction box cover.

[0072] The motor of the present invention has the advantages of the shaft end connection structure because it is equipped with a shaft end connection structure that prevents bearing electro-corrosion. Furthermore, the shaft end connection structure can effectively prevent bearing electro-corrosion of the bearing 3, thereby improving the operating stability and service life of the motor.

[0073] In other embodiments, the shaft end connection structure for preventing bearing electro-corrosion can also be set at the front end of the rotating shaft 2. Specifically, the front end of the rotating shaft 2 extends out of the front end cover 11, the junction box cover is fixed on the outside of the front end cover 11, and the shaft end connection structure is located between the front end of the rotating shaft 2 and the junction box cover.

[0074] In other embodiments, anti-bearing electro-corrosion shaft end connection structures can also be provided at both the front and rear ends of the rotating shaft 2.

[0075] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. The technical features involved in the various embodiments of the present invention described above can be combined with each other as long as they do not conflict with each other. All technical solutions within the scope of the present invention's concept are within the protection scope of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should be considered within the protection scope of the present invention.

Claims

1. A shaft end connection structure for preventing bearing electro-corrosion, characterized in that: The assembly includes an end cap (1), a rotating shaft (2), a load-bearing bearing (3), a conductive bearing (4), a conductive connection assembly (5), and a grounding fixing part (7). The rotating shaft (2) is fixed to the end cap (1) by the load-bearing bearing (3). The end of the rotating shaft (2) has a mounting shaft (21) extending outward along the axis. The inner ring of the conductive bearing (4) is fixedly fitted with the outer circumference of the mounting shaft (21). The diameter of the conductive bearing (4) is smaller than the diameter of the load-bearing bearing (3). The conductive connection assembly (5) includes an outer sleeve (51) and an inner insert (52). The outer sleeve (51)... Installed on the grounding fixing part (7), the embedded end of the inner part (52) is located inside the sleeve end of the outer sleeve (51), and the non-embedded end is fastened to the outer ring of the conductive bearing (4). There are at least two inner parts (52), which are evenly arranged along the circumference of the conductive bearing (4). The embedded end of each inner part (52) is provided with an elastic element (6) to elastically limit the inner part (52) between the conductive bearing (4) and the sleeve end of the outer sleeve (51). The sleeve end of the outer sleeve (51) has a closing structure (50). The insert (52) has a sliding part (521) and a limiting part (522). The sliding part (521) passes through the closing structure (50), and the limiting part (522) is used to prevent the insert (52) from coming out of the closing structure (50). The closing structure (50) includes a closing shoulder (501) and a closing neck (502). The outer periphery of the sliding part (521) fits against the inner periphery of the closing neck (502), and the outer periphery of the limiting part (522) fits against the inner periphery of the closing shoulder (501). The outer sleeve (51) is a mounting plate, and the end of the mounting plate... At least two of the aforementioned closing structures (50) are provided symmetrically on the surface. Each closing structure (50) has an insert (52) and an elastic element (6) that cooperate with it. The center of the end face of the socket end of the mounting plate is provided with an inwardly recessed first mounting groove (511). The grounding fixing part (7) is provided with a second mounting groove (71). The center of the second mounting groove (71) is provided with a second boss (711). The non-socket end of the mounting plate is embedded in the second mounting groove (71). The bottom of the first mounting groove (511) is attached to the second boss (711) and fastened by screws.

2. The shaft end connection structure for preventing bearing electro-corrosion according to claim 1, characterized in that: The non-embedded end of the insert (52) abuts against the end face of the outer ring of the conductive bearing (4).

3. The shaft end connection structure for preventing bearing electro-corrosion according to claim 1, characterized in that: The insert (52) has a groove at its insertion end for mounting the elastic element (6).

4. The shaft end connection structure for preventing bearing electro-corrosion according to claim 1, characterized in that: The elastic element (6) is a spring.

5. The shaft end connection structure for preventing bearing electro-corrosion according to claim 1, characterized in that: The elastic element (6) is located between the embedded end of the insert (52) and the grounding fixing part (7).

6. The shaft end connection structure for preventing bearing electro-corrosion according to claim 1, characterized in that: The grounding fixing part (7) is a junction box cover plate. The junction box cover plate is fixed to the outside of the end cover (1) and forms a closed conductive bearing chamber with the end cover (1).

7. An electric motor, characterized in that, The shaft end connection structure for preventing bearing electro-corrosion as described in any one of claims 1 to 6, wherein the end cover (1) includes a front end cover (11) and a rear end cover (12), the front end of the rotating shaft (2) extends out of the front end cover (11), the grounding fixing part (7) is fixed outside the front end cover (11), and the shaft end connection structure is located between the front end of the rotating shaft (2) and the grounding fixing part (7); And / or, the end cap (1) includes a front end cap (11) and a rear end cap (12), the rear end of the rotating shaft (2) extends out of the rear end cap (12), the grounding fixing part (7) is fixed outside the rear end cap (12), and the shaft end connection structure is located between the rear end of the rotating shaft (2) and the grounding fixing part (7).

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