CN110768440A

CN110768440A - Bearing protection device

Info

Publication number: CN110768440A
Application number: CN201810827703.XA
Authority: CN
Inventors: 刘文弢; 彭再武; 石魏; 赵铃; 罗骁; 田景笔; 罗宏亮; 李明; 李政颖
Original assignee: Hunan CRRC Times Electric Vehicle Co Ltd
Current assignee: Hunan CRRC Times Electric Vehicle Co Ltd
Priority date: 2018-07-25
Filing date: 2018-07-25
Publication date: 2020-02-07
Anticipated expiration: 2038-07-25
Also published as: CN110768440B

Abstract

The invention discloses a bearing protection device which comprises a base, a cover plate and a plurality of carbon brush assemblies, wherein each carbon brush assembly comprises a carbon brush and a carbon brush fixing frame, the carbon brush is rotatably installed on the carbon brush fixing frame, an installation through hole is formed in the base, a plurality of axially and uniformly arranged installation grooves are formed in the inner wall of the installation through hole, the number of the installation grooves is the same as that of the carbon brush assemblies, the carbon brush fixing frame is located in the installation grooves, the carbon brush extends out of the installation grooves and points to the center of the installation through hole, and the cover plate is used for fixing each. According to the invention, the carbon brush is additionally arranged on the output shaft of the motor, and the voltage of the motor shaft is led out to the motor end cover, so that the electric potentials of the inner ring and the outer ring of the motor bearing are basically equal, and the local high temperature caused by local discharge generated by common-mode current can be effectively inhibited, thereby avoiding the formation of the rubbing lines on the inner ring and the outer ring of the motor bearing, reducing the vibration and the noise of an automobile, and improving the service life of the bearing and the comfort of the automobile.

Description

Bearing protection device

Technical Field

The invention relates to the technical field of pure electric drive, in particular to a bearing protection device.

Background

When a new energy commercial vehicle (mainly a pure electric vehicle) generally adopts a PWM frequency converter to supply power to a motor, the sum of three-phase output voltage vectors is not zero, namely the common-mode voltage of a central point is not zero. The coupling capacitance exists between the stator and the rotor and between the stator windings of the motor. When the PWM technology is adopted for power supply, the motor shaft, the motor shell and the motor bearing form an electric loop to generate shaft current. When the shaft current is discharged locally, a local high-temperature working environment is formed, the inner ring and the outer ring of the bearing and the balls can be melted to generate grooves, and the inner ring and the outer ring of the bearing generate clothes rubbing patterns in the past, so that the service life of the bearing is seriously influenced, and the NVH (noise, vibration and harshness) of an automobile is greatly influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a bearing protection device which can effectively inhibit local high temperature caused by local discharge generated by common-mode current, thereby avoiding the formation of clothes rubbing on the inner ring and the outer ring of a motor bearing, reducing the vibration and the noise of an automobile, prolonging the service life of the bearing and improving the comfort of the automobile.

In order to solve the technical problems, the invention adopts the following technical scheme:

the utility model provides a bearing protection device, includes base, apron and a plurality of carbon brush subassembly, the carbon brush subassembly includes carbon brush and carbon brush mount, the carbon brush is rotatable installs on the carbon brush mount, the base is equipped with the installation through-hole, the inner wall of installation through-hole is equipped with the even mounting groove of arranging of a plurality of axial, the quantity of mounting groove is the same with the quantity of carbon brush subassembly, the carbon brush mount is located the mounting groove, the carbon brush stretches out the center of the directional installation through-hole of mounting groove, the apron is used for being fixed in each mounting groove with each carbon brush subassembly.

As a further improvement of the above technical solution:

the carbon brush assembly further comprises an elastic piece, the elastic piece and the carbon brush fixing frame are located in the mounting groove, and the elastic piece is abutted between the carbon brush fixing frame and the mounting groove.

The elastic piece is a spring.

The other end of the carbon brush fixing frame is provided with a positioning hole, one end of the spring abuts against the inner wall of the mounting groove, and the other end of the spring is located in the positioning hole.

The carbon brush fixing frame is characterized in that two symmetrical lug plates are arranged at one end of the carbon brush fixing frame, a bolt penetrates through the two lug plates and is fixed on the two lug plates, and the carbon brush is arranged on the part of the bolt between the two lug plates.

The part of the bolt between the two lug plates is sleeved with a sleeve, and the carbon brush is fixedly sleeved on the sleeve.

And a limiting part for preventing the carbon brush fixing frame from radially separating from the mounting through hole is arranged in the mounting groove.

The base is circular.

The cover plate is circular, and a center hole of the cover plate is matched with the mounting through hole of the base.

The cover plate is fixed on the base through screws or clamped on the base through clamping buckles.

Compared with the prior art, the invention has the advantages that:

according to the bearing protection device, the carbon brush is additionally arranged on the motor output shaft, the current of the motor output shaft flows to the end cover of the motor through the carbon brush, the sleeve, the bolt, the carbon brush fixing frame and the base, and the voltage of the motor output shaft is led out to the motor end cover, so that the electric potentials of the inner ring and the outer ring of the bearing in the motor end cover are basically equal, the local high temperature caused by local discharge generated by common mode current can be effectively inhibited, the shaft voltage can be effectively reduced, the bearing is protected from being damaged, the formation of clothes rubbing patterns on the inner ring and the outer ring of the motor bearing is avoided, the vibration and the noise of an automobile are reduced.

Drawings

Fig. 1 is a schematic perspective exploded view of a bearing protector according to the present invention.

Fig. 2 is a schematic front view of the bearing protection device of the present invention.

Fig. 3 is a schematic view of the back of the bearing protection device of the present invention.

Fig. 4 is a schematic view showing the mounting position of the bearing protector on the output shaft according to the present invention.

The reference numerals in the figures denote:

1. a base; 11. mounting a through hole; 12. connecting holes; 2. a cover plate; 3. a carbon brush; 4. a carbon brush fixing frame; 41. positioning holes; 42. an ear plate; 43. a bolt; 5. mounting grooves; 51. a limiting part; 6. an elastic member; 7. a permanent magnet synchronous motor; 8. an output shaft; 9. an output flange plate.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples of the specification.

The bearing protection device disclosed by the invention is mainly applied to a new energy commercial vehicle and used for connecting the inner ring and the outer ring of the bearing based on the principle that circuit discharge always proceeds along the minimum impedance path, and can effectively reduce the potential difference between the inner ring and the outer ring of the motor and reduce the electric corrosion damage of the bearing.

As shown in fig. 1 to 3, the bearing protection device of this embodiment, including base 1, apron 2 and a plurality of carbon brush subassembly, the carbon brush subassembly includes carbon brush 3 and carbon brush mount 4, rotatable the installing on carbon brush mount 4 of carbon brush 3, base 1 is equipped with installation through-hole 11, the inner wall of installation through-hole 11 is equipped with a plurality of axial mounting grooves 5 of evenly arranging, the quantity of mounting groove 5 is the same with the quantity of carbon brush subassembly, carbon brush mount 4 is located mounting groove 5, carbon brush 3 stretches out the center of the directional installation through-hole 11 of mounting groove 5, apron 2 is used for being fixed in each mounting groove 5 with each carbon brush subassembly.

In this embodiment, the carbon brush assemblies are provided in six groups (the number is not limited, and six groups are preferred). When in use, as shown in fig. 4, the bearing protection device is sleeved on the output shaft 8 of the permanent magnet synchronous motor 7 after being assembled, and is connected with the inner ring and the outer ring of the bearing of the motor. All the carbon brushes 3 are in contact with the output shaft 8.

In this embodiment, specifically, the carbon brush assembly further includes an elastic member 6, the elastic member 6 and the carbon brush fixing frame 4 are located in the mounting groove 5, and the elastic member 6 abuts between the carbon brush fixing frame 4 and the mounting groove 5. Specifically, the elastic member 6 is a spring, the other end of the carbon brush fixing frame 4 is provided with a positioning hole 41, one end of the spring abuts against the inner wall of the mounting groove 5, the other end of the spring is located in the positioning hole 41, and the positioning hole 41 can prevent the spring from moving in a dislocation manner. During the transmission process of the motor, the carbon brush 3 can be pressed on the surface of the output shaft 8 to contact with the output shaft all the time due to the acting force of the spring. Besides this embodiment, the elastic member 6 may be a spring.

In this embodiment, one end of the carbon brush fixing frame 4 is provided with two symmetrical ear plates 42, a bolt 43 is penetrated and fixed on the two ear plates 42, a sleeve is sleeved on a part of the bolt 43 between the two ear plates 42, and the carbon brush 3 is fixedly sleeved on the sleeve. The main body of the carbon brush holder 4 is a square, and two ear plates 42 are fixed to one end face of the square. The mounting groove 5 is provided with a limiting part 51 for preventing the carbon brush fixing frame 4 from radially separating along the mounting through hole 11. Namely, the square body of the carbon brush fixing frame 4 is positioned in the mounting groove 5 and can be blocked by the limiting part 51, so that the carbon brush fixing frame is prevented from being separated from the mounting groove 5, and the two lug plates 42 and the carbon brush 3 arranged on the lug plates extend out of the mounting groove 5. The height of the carbon brush fixing frame 4 is basically equal to that of the mounting groove 5, so that the cover plate 2 can cover the carbon brush fixing frame 4 conveniently.

In this embodiment, the base 1 is annular and is formed by fixing two semicircular blocks in half. The cover plate 2 is circular and also comprises two arc blocks in half, and the central hole of the cover plate 2 is matched with the mounting through hole 11 of the base 1. The cover plate 2 is fixed on the base 1 by screws, and besides this embodiment, the cover plate 2 can also be clamped on the base 1 by clips.

In this embodiment, the base 1 is provided with a connecting hole 12 for connecting with an end cover of the permanent magnet synchronous motor 7, and the connecting hole 12 penetrates through the cover plate 2 and is used for fixing the bearing protection device and the motor end cover together. In addition, the clamping piece can be used for clamping the protection device and the motor end cover together so that the protection device and the motor end cover are electrically connected.

The assembling process comprises the following steps:

firstly, the carbon brush 3 and the carbon brush fixing frame 4 are assembled, then the spring is arranged in the installation groove 5, the carbon brush fixing frame 4 is arranged in the installation groove 5 from top to bottom, one end of the spring is inserted into the positioning hole 41 by compression, all the carbon brush fixing frames 4 are sequentially arranged, and finally the cover plate 2 is covered and the cover plate 2 is kept to be in contact with the carbon brush fixing frame 4. Because the circuit discharge always goes along the path of minimum impedance, the current of the motor output shaft 8 flows to the end cover of the permanent magnet synchronous motor 7 through the carbon brush 3, the sleeve, the bolt 43, the carbon brush fixing frame 4 and the base 1, so that the electric potentials of the inner ring and the outer ring of the bearing of the permanent magnet synchronous motor 7 are basically equal, the shaft voltage can be effectively reduced, and the bearing is protected from being damaged.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.

Claims

1. The utility model provides a bearing protection device which characterized in that: including base (1), apron (2) and a plurality of carbon brush subassembly, the carbon brush subassembly includes carbon brush (3) and carbon brush mount (4), rotatable the installing on carbon brush mount (4) of carbon brush (3), base (1) is equipped with installation through-hole (11), the inner wall of installation through-hole (11) is equipped with mounting groove (5) that a plurality of axial were evenly arranged, the quantity of mounting groove (5) is the same with the quantity of carbon brush subassembly, carbon brush mount (4) are located mounting groove (5), carbon brush (3) stretch out the center of the directional mounting hole (11) of mounting groove (5), apron (2) are used for being fixed in each mounting groove (5) with each carbon brush subassembly.

2. The bearing protection device of claim 1, wherein: the carbon brush assembly further comprises an elastic piece (6), the elastic piece (6) and the carbon brush fixing frame (4) are located in the mounting groove (5), and the elastic piece (6) is abutted between the carbon brush fixing frame (4) and the mounting groove (5).

3. The bearing protection device of claim 2, wherein: the elastic piece (6) is a spring.

4. The bearing protection device of claim 3, wherein: the other end of the carbon brush fixing frame (4) is provided with a positioning hole (41), one end of the spring abuts against the inner wall of the mounting groove (5), and the other end of the spring is located in the positioning hole (41).

5. The bearing protection device according to any one of claims 1 to 4, wherein: the carbon brush fixing frame is characterized in that one end of the carbon brush fixing frame (4) is provided with two symmetrical lug plates (42), a bolt (43) penetrates through the two lug plates (42) and is fixed on the two lug plates, and the carbon brush (3) is arranged on the part, between the two lug plates (42), of the bolt (43).

6. The bearing protection device of claim 5, wherein: the part of the bolt (43) between the two lug plates (42) is sleeved with a sleeve, and the carbon brush (3) is fixedly sleeved on the sleeve.

7. The bearing protection device according to any one of claims 1 to 4, wherein: and a limiting part (51) for preventing the carbon brush fixing frame (4) from radially separating from the mounting through hole (11) is arranged in the mounting groove (5).

8. The bearing protection device according to any one of claims 1 to 4, wherein: the base (1) is annular.

9. The bearing protection device of claim 8, wherein: the cover plate (2) is annular, and a center hole of the cover plate (2) is matched with the mounting through hole (11) of the base (1).

10. The bearing protection device according to any one of claims 1 to 4, wherein: the cover plate (2) is fixed on the base (1) through screws or clamped on the base (1) through clamping buckles.