Motor shaft seal and shaft current protection structure

Abstract

The utility model discloses a motor shaft seal and shaft current protection structure which comprises a motor. An outer shaft seal part is arranged between an end cover of the motor and a motor shaft, a grounding conductive part is installed on a bearing inner cover of the motor, the motor shaft is peripherally enclosed by the grounding conductive part to form a closed ring body structure in conductive contact with a shaft body, and an inner shaft seal part is arranged between the bearing inner cover and the grounding conductive part. And the outer shaft seal part and the inner shaft seal part are matched to axially seal a bearing chamber of the motor. According to the utility model, axial inner and outer shaft sealing and surrounding contact conduction are carried out on the motor, so that the protection grade of the motor is effectively improved, and shaft current is prevented from being generated.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor sealing and shaft current protection, and particularly relates to a motor shaft seal and shaft current protection structure. Background Art

[0002] When manufacturing a motor, due to the inevitable uneven air gap between the stator and rotor during the production process, the magnetic resistance is uneven, resulting in shaft voltage. When the shaft voltage is too large, shaft current is generated. Now, a large number of frequency converters are used, which also easily generate shaft current. The shaft current corrodes the motor bearings, damages the bearings, makes the motor vibrate and generate more noise, and produces electromagnetic interference, increases energy consumption, and reduces efficiency. The existing measures to prevent shaft current generation on the market are as follows: First, use a grounding carbon brush to contact the shaft and lead the shaft current out of the motor to ground, but the carbon brush is easily worn and has poor contact with the shaft, resulting in grounding failure; Second, use an insulating end cover, and the insulation effect is easily invaded by external pollution, resulting in insulation failure. The protection of motor shaft current is not ideal. Summary of the Invention

[0003] Object of the Invention: In order to overcome the deficiencies in the prior art, the utility model provides a motor shaft seal and shaft current protection structure, which effectively improves the protection level of the motor and avoids the generation of shaft current by performing axial internal and external shaft seals on the motor and surrounding contact conduction.

[0004] Technical Solution: To achieve the above object, a motor shaft seal and shaft current protection structure of the utility model includes a motor; an external shaft seal component is arranged between the end cover of the motor and the motor shaft, a grounding and conductive component is installed on the inner cover of the bearing of the motor, the grounding and conductive component circumferentially encloses the motor shaft to form a closed ring structure in conductive contact with the shaft body, an internal shaft seal component is arranged between the inner cover of the bearing and the grounding and conductive component, and the external shaft seal component and the internal shaft seal component cooperate to axially seal the bearing chamber of the motor.

[0005] Further, the end cover has an external sealing cavity, the inner cover of the bearing has an internal sealing cavity, the external shaft seal component is installed in the external sealing cavity, and the internal shaft seal component is installed in the internal sealing cavity.

[0006] Further, the external shaft seal component includes an external labyrinth shaft surface oil seal and an external skeleton oil seal, and the external labyrinth shaft surface oil seal covers the external skeleton oil seal.

[0007] Further, the internal shaft seal component includes an internal skeleton oil seal.

[0008] Further, the grounding and conductive component is a grounding ring in coaxial electrical contact with the motor shaft of the motor.

[0009] Further, the grounding ring includes an insulating outer ring and a conductive inner ring that are coaxially connected. The insulating outer ring is connected to the inner bearing cover of the motor, and the conductive inner ring is coaxially in contact with the shaft body of the motor shaft.

[0010] Further, a fastener is provided between the insulating outer ring and the conductive inner ring, and the insulating outer ring and the conductive inner ring are detachably installed through the fastener.

[0011] Further, a contact is connected to the conductive inner ring through a conducting wire, and the conducting wire is embedded in a wire groove formed on the surface of the insulating outer ring.

[0012] Further, the conductive inner ring is made of wear-resistant conductive fiber material.

[0013] Beneficial effects: By performing axial internal and external shaft seals and surrounding contact conduction on the motor, the protection level of the motor is effectively improved and the generation of shaft current is avoided. Among them, the shaft seal can effectively prevent dust and liquid from entering, improve the stable operation ability of the motor in harsh and complex environments, and the surrounding contact conduction can timely divert the shaft current to the ground, improve the shaft current protection ability of the motor, extend the service life, and ensure safe operation. Description of the Drawings

[0014] Fig. Figure 1 is a half-sectional structural view of one shaft end of the motor of the present invention;

[0015] Fig. Figure 2 is an overall structural view of the grounding and conducting component;

[0016] Fig. Figure 3 is an exploded structural view of the grounding and conducting component. Specific Embodiments

[0017] The present invention will be further described below with reference to the drawings.

[0018] As shown in Fig. Figure 1As shown in the figure, a motor shaft seal and shaft current protection structure includes a motor 1. An outer shaft seal component 4 is provided between the end cover 2 and the motor shaft 3 of the motor 1. A grounding conductive component 6 is installed on the bearing inner cover 5 of the motor 1. The grounding conductive component 6 circumferentially encloses the motor shaft 3 to form a closed ring structure in conductive contact with the shaft body. An inner shaft seal component 7 is provided between the bearing inner cover 5 and the grounding conductive component 6. The outer shaft seal component 4 and the inner shaft seal component 7 cooperate to axially seal the bearing chamber 8 of the motor 1. By axially sealing the motor 1 both inside and outside and providing circumferential contact conduction, the protection level of the motor is effectively improved and the generation of shaft current is avoided. Among them, the shaft seal can effectively prevent dust and liquid from entering, improving the stable operation ability of the motor in harsh and complex environments. The circumferential contact conduction can timely divert the shaft current to the ground, improving the shaft current protection ability of the motor, increasing the service life, and ensuring safe operation.

[0019] As shown in the attached Figure 1 figure, the end cover 2 has an outer sealing cavity 20, the bearing inner cover 5 has an inner sealing cavity 50, the outer shaft seal component 4 is installed in the outer sealing cavity 20, and the inner shaft seal component 7 is installed in the inner sealing cavity 50. More specifically, the outer shaft seal component 4 includes an outer labyrinth shaft surface oil seal 41 and an outer skeleton oil seal 42. The outer labyrinth shaft surface oil seal 41 covers the outer skeleton oil seal 42, improving the overall protection level of the motor, effectively preventing dust and liquid from entering, and enabling the motor to operate stably in harsh environments.

[0020] The inner shaft seal component 7 includes an inner skeleton oil seal. The grounding conductive component 6 is a grounding ring in coaxial electrical contact with the motor shaft 3 of the motor 1, effectively preventing grease from flowing out and polluting the grounding ring, strengthening the effectiveness of the grounding of the grounding ring, and increasing the service life of the grounding ring.

[0021] As shown in the attached Figure 2 and attached Figure 3 figure, the grounding ring includes an insulating outer ring 61 and a conductive inner ring 62 connected coaxially. The insulating outer ring 61 is connected to the bearing inner cover 5 of the motor 1. Specifically, the insulating outer ring 61 is connected to the bearing inner cover 5 by bolts. The conductive inner ring 62 is arranged in coaxial contact with the shaft body of the motor shaft 3. A fastener 63 is provided between the insulating outer ring 61 and the conductive inner ring 62. The insulating outer ring 61 and the conductive inner ring 62 are detachably installed through the fastener 63. The fastener 63 is a bolt and nut assembly, which is convenient for replacement when the conductive inner ring 62 is worn. Moreover, the conductive inner ring 62 is made of wear-resistant conductive fiber material. The conductive inner ring 62 is connected to a contact 65 through a wire 64. The wire 64 is embedded in a wire groove 610 opened on the surface of the insulating outer ring 61. The contact 65 can be conveniently connected to a grounding conductive connecting component, and the installation is simple.

[0022] The above are only the preferred embodiments of the present utility model. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present utility model, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present utility model.

Claims

1. A motor shaft seal and shaft current protection structure, characterized in that: The invention comprises a motor (1); an outer shaft seal component (4) is arranged between an end cover (2) of the motor (1) and a motor shaft (3); a grounding conductive component (6) is installed on a bearing inner cover (5) of the motor (1); the grounding conductive component (6) circumferentially surrounds the motor shaft (3) to form a closed ring structure in conductive contact with the shaft body; an inner shaft seal component (7) is arranged between the bearing inner cover (5) and the grounding conductive component (6); the outer shaft seal component (4) and the inner shaft seal component (7) cooperate to axially seal a bearing chamber (8) of the motor (1).

2. The motor shaft seal and shaft current protection structure according to claim 1, characterized in that: The end cover (2) has an outer sealing cavity (20), the bearing inner cover (5) has an inner sealing cavity (50), the outer shaft sealing component (4) is installed in the outer sealing cavity (20), and the inner shaft sealing component (7) is installed in the inner sealing cavity (50).

3. The motor shaft seal and shaft current protection structure according to claim 1, characterized in that: The outer shaft seal component (4) comprises an outer labyrinth shaft surface oil seal (41) and an outer skeleton oil seal (42), and the outer labyrinth shaft surface oil seal (41) covers the outer skeleton oil seal (42).

4. The motor shaft seal and shaft current protection structure according to claim 1, characterized in that: The inner shaft sealing component (7) comprises an inner skeleton oil seal.

5. The motor shaft seal and shaft current protection structure according to claim 1, characterized in that: The grounding conductive component (6) is a grounding ring that is in coaxial electrical contact with the motor shaft (3) of the motor (1).

6. The motor shaft seal and shaft current protection structure according to claim 5, characterized in that: The grounding ring comprises an insulating outer ring (61) and a conductive inner ring (62) which are coaxially connected, the insulating outer ring (61) being connected to the bearing inner cover (5) of the motor (1), and the conductive inner ring (62) being coaxially contacting the shaft body of the motor shaft (3).

7. The motor shaft seal and shaft current protection structure according to claim 6, characterized in that: A fastener (63) is provided between the insulating outer ring (61) and the conductive inner ring (62), and the insulating outer ring (61) and the conductive inner ring (62) are detachably mounted via the fastener (63).

8. The motor shaft seal and shaft current protection structure according to claim 6, characterized in that: The conductive inner ring (62) channel conductor (64) is connected to a contact (65), and the conductor (64) is embedded in a conductor groove (610) provided on the surface of the insulating outer ring (61).

9. A motor shaft seal and shaft current protection structure according to claim 6, 7 or 8, characterized in that: The conductive inner ring (62) is made of wear-resistant conductive fiber material.

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