CN111211647A

CN111211647A - Brushless motor

Info

Publication number: CN111211647A
Application number: CN201811392433.0A
Authority: CN
Inventors: 朱宇飞; 刘文俊; 王震宇
Original assignee: Suzhou Gala Tech Power Co ltd
Current assignee: Suzhou jiaxinchuang Microelectronics Co.,Ltd.
Priority date: 2018-11-21
Filing date: 2018-11-21
Publication date: 2020-05-29

Abstract

The invention discloses a brushless motor, which comprises a base and a rotating shaft, wherein the rotating shaft is rotatably arranged on the base, the brushless motor also comprises a discharge part which is sleeved with the end part of the rotating shaft, a cavity is arranged between the end part of the rotating shaft and the discharge part, a conductor is filled in the cavity, the conductor is conductive liquid or conductive powder, the discharge part is connected with the rotating shaft through the conductor, and the discharge part is grounded; through the discharge portion that sets up ground connection, the discharge portion is connected through electric conductor and pivot electricity, derives axle current and bearing current, and the voltage value at balanced pivot both ends prevents to cause the injury to bearing and gear, and the device simple structure easily realizes, and stable in structure is difficult for becoming invalid, and is little to the pivoted influence of countershaft, and the effectual of realization.

Description

Brushless motor

Technical Field

The invention relates to the field of motors, in particular to a brushless motor.

Background

Under the conditions of magnetic imbalance and other reasons, shaft voltage is generated on a rotating shaft of the motor, the shaft voltage forms a loop between a base and a shell, shaft current is generated, and bearing current is generated. Generally, a certain gap exists between a rolling body of the bearing and an inner ring and an outer ring, lubricating oil is arranged in the bearing for lubrication, when the shaft voltage is higher than a certain threshold value, a lubricating oil isolating film in the bearing gap is broken down by high voltage electricity, and the electric arc discharge is generated when the electric potential of the inner ring of the bearing is too high relative to the electric potential of the outer ring, so that the bearing surface is damaged, and the service life of the bearing is terminated in advance.

In order to avoid bearing current damage to the bearing, an insulated bearing is adopted at present, but shaft voltage discharges to the ground through a gear meshing surface, damage is caused to the gear surface, and the gear fails in advance.

Disclosure of Invention

In order to solve the problem that the bearing current damages the bearing or the gear in the prior art, the invention aims to provide a brushless motor which reduces or eliminates the bearing current.

In order to achieve one of the above objects, an embodiment of the present invention provides a brushless motor, which includes a base, a rotating shaft, and a discharging portion sleeved to an end of the rotating shaft, wherein a cavity is disposed between the end of the rotating shaft and the discharging portion, the cavity is filled with a conductive body, the conductive body is a conductive liquid or a conductive powder, the discharging portion is connected to the rotating shaft through a conductive body, and the discharging portion is grounded.

As a further improvement of an embodiment of the present invention, a groove is disposed at an end of the rotating shaft, a conductor is disposed in the groove, and the discharge portion is inserted into the groove.

As a further improvement of an embodiment of the present invention, a sealing ring is disposed at an opening of the groove, and the discharge portion is inserted into the groove through the sealing ring.

As a further improvement of an embodiment of the present invention, the discharge portion is provided in a needle shape, and a needle of the discharge portion passes through the seal ring to contact the conductive body.

As a further improvement of an embodiment of the present invention, the discharge portion is annular, the rotating shaft is sleeved inside the discharge portion, and the conductor is disposed inside the discharge portion.

As a further improvement of an embodiment of the present invention, a seal ring is disposed at an end of the discharge portion, and the rotating shaft is inserted into the conductor through the seal ring.

As a further improvement of an embodiment of the present invention, the discharge portion is connected to the base, both the discharge portion and the base are provided as conductors, and the base is grounded.

As a further improvement of an embodiment of the invention, the electrical conductor is provided as an electrically conductive grease.

As a further improvement of an embodiment of the present invention, the brushless motor is an inner rotor brushless motor, the brushless motor includes a rotor and a stator, the stator includes a housing and a magnet, the housing is fixed on the base, the magnet is fixed inside the housing, and the rotor is arranged inside the magnet.

Compared with the prior art, the invention has the following beneficial effects: through the discharge portion that sets up ground connection, the discharge portion is connected through electric conductor and pivot electricity, derives axle current and bearing current, and the voltage value at balanced pivot both ends prevents to cause the injury to bearing and gear, and the device simple structure easily realizes, and stable in structure is difficult for becoming invalid, and is little to the pivoted influence of countershaft, and the effectual of realization.

Drawings

Fig. 1 is a sectional view of a brushless motor according to an embodiment of the present invention;

fig. 2 is a partially enlarged view of a brushless motor according to an embodiment of the present invention at a;

fig. 3 is a schematic structural diagram of a brushless motor according to an embodiment of the present invention;

100, a brushless motor; 1. a machine base; 2. a stator; 3. a rotor; 4. a rotating shaft; 41. a groove; 5. a bearing; 51. an inner ring; 52. a rolling body; 53. an outer ring; 6. a discharge section.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention.

Example 1

A first embodiment of the present invention provides a brushless motor 100, as shown in fig. 1 to 3, the brushless motor 100 includes a base 1, a rotor 3 and a stator 2 are disposed on the base 1, a rotating shaft 4 is connected to the rotor 3, for the brushless motor 100 with an inner rotor 3, the rotor 3 is disposed at the inner side, the rotating shaft 4 is disposed in the rotor 3, and the stator 2 is disposed at the periphery of the rotor 3; for the brushless motor 100 with the outer rotor 3, the stator 2 is arranged at the inner side, the rotor 3 is arranged at the periphery of the stator 2, the end part of the rotor 3 is connected with the rotating shaft 4 and inserted into the stator 2, and the axis of the rotating shaft 4 and the axis of the stator 2 are in the same line; at least two bearings 5 are arranged on the rotating shaft 4, the bearings 5 are connected with the machine base 1 or other supporting mechanisms, and the bearings 5 are used for supporting the rotating shaft 4 to operate.

The end of the rotating shaft 4 is provided with the discharging part 6, the discharging part 6 is used for leading out the shaft current on the rotating shaft 4, the discharging part 6 is connected with the rotating shaft 4 through a conductor, the discharging part 6 is grounded, the electricity on the rotating shaft 4 is transmitted to the discharging part 6 through the conductor and then is discharged through the conductor in a grounded manner, the discharging in the gap of the bearing 5 requires voltage to break through an oil film or air and then violently discharges, and the discharging part 6 can be directly discharged in a grounded manner, so that the damage to the bearing 5 is avoided.

Further, in this embodiment, a groove 41 is provided at the end of the rotating shaft 4, a conductive body is provided in the groove 41, and the discharge portion 6 is inserted into the groove 41.

Further, a sealing ring is arranged at the opening of the groove 41, and the discharge part 6 penetrates through the sealing ring and is inserted into the groove 41; the sealing ring is arranged, so that the leakage of the electric conductor in the groove 41 can be prevented, the electric conductor is limited in the groove 41 of the rotating shaft 4, and the discharging part 6 penetrates through the sealing ring and is in contact with the electric conductor in the groove to realize the electric conduction.

Further, the discharge part 6 is connected to the base 1, the discharge part 6 and the base 1 are both provided with conductors, and the base 1 is grounded; that is, the discharge unit 6 discharges electricity through the housing 1, which is one embodiment of this embodiment.

Further, the conductive body in this embodiment is provided as a conductive liquid or a conductive powder; the conductive liquid or the conductive powder is beneficial to reducing the friction value between the discharge part 6 and the rotating shaft 4, and the electricity of the rotating shaft 4 is transmitted to the discharge part 6 through the electric conductor on the premise of reducing the friction as much as possible and not influencing the rotation of the rotating shaft 4.

Further, in the present embodiment, the discharge part 6 is provided in a needle shape, and a needle of the needle-shaped discharge part 6 passes through the seal ring to contact the conductive body. The needle-shaped discharge part 6 is beneficial to reducing the contact area of the discharge part 6 and other parts, thereby reducing friction, not influencing the rotation of the rotating shaft 4 and simultaneously realizing the effect of discharging electricity on the rotating shaft 4.

Further, the electrical conductor is provided as conductive grease in this embodiment; use conductive grease to be favorable to avoiding revealing of electric conductor, the aforesaid sealing washer that sets up at the opening part of recess 41 of rethread will adopt conductive grease's electric conductor lock in the recess 41 of pivot 4, discharge portion 6 inserts and rotates in the conductive grease in recess 41, and coefficient of friction is little, and the electricity on the pivot 4 transmits through conductive grease for discharge portion 6, has realized that discharge portion 6 is static while, does not influence the rotation of pivot 4.

Further, the brushless motor 100 is configured as an inner rotor 3 brushless motor 100, and the stator 2 includes a housing fixed to the base 1 and a magnet fixed inside the housing, and the rotor 3 is disposed inside the magnet.

When brushless motor 100 is external rotor 3 brushless motor 100, stator 2 and rotor 3 are exchanged, and the arrangement of the electric conductors and the beneficial effects produced are the same as those of internal rotor 3 brushless motor 100.

Compared with the prior art, the invention has the following beneficial effects:

(1) through the discharge portion 6 that sets up ground connection, discharge portion 6 passes through the electric conductor and is connected with pivot 4, derives axle current and bearing current, and the voltage value at 4 both ends of balanced pivot prevents to cause the injury to bearing 5 and gear, and the device simple structure easily realizes, and stable in structure is difficult for becoming invalid, and is little to pivot 4 pivoted influence, and the effectual of realization.

(2) The electric conductor adopts the modes of conductive liquid, conductive powder, conductive grease and the like, so that when the discharge part 6 is static, the current on the rotating shaft 4 is received through the conductive part without influencing the rotation of the rotating shaft 4.

(3) The end part of the rotating shaft 4 is provided with a groove 41 and a sealing ring, so that the electric conductor is locked in the rotating shaft 4, and the leakage of the electric conductor is avoided.

Example 2

This example differs from example 1 only in that: the discharge part 6 is annular, the rotating shaft 4 is sleeved inside the discharge part 6, and a conductor is arranged inside the discharge part 6. This difference will be described in detail below, and the other parts that are the same as those in embodiment 1 will not be described again.

In this embodiment, the discharging portion 6 is sleeved outside the rotating shaft 4, which is another implementation form of the same concept as that of embodiment 1 in this scheme, further, a sealing ring is disposed at an end of the discharging portion 6, the rotating shaft 4 penetrates through the sealing ring and is inserted into the electric conductor to prevent the electric conductor from leaking, the discharging portion 6 is stationary, and the rotating shaft 4 rotates inside the discharging portion 6.

Similarly, the matching relationship between the discharge part 6 and the rotating shaft 4 can be in other forms, and when the requirement that the electricity on the rotating shaft 4 is discharged through the peripheral discharge part 6 is met, and the discharge part 6 is grounded to lead out the current, the purpose of the scheme can be achieved.

The detailed description set forth above is merely a specific description of possible embodiments of the present invention and is not intended to limit the scope of the invention, which is intended to include within the scope of the invention equivalent embodiments or modifications that do not depart from the technical spirit of the present invention.

Claims

1. The utility model provides a brushless motor, brushless motor includes frame and pivot, pivot pivoted setting is in on the frame, its characterized in that still include with the discharge portion that the tip of pivot cup jointed mutually, the pivot tip with set up the cavity between the discharge portion, fill the electric conductor in the cavity, the electric conductor sets up to conducting liquid or conductive powder, discharge portion with the pivot passes through the conductive connection, discharge portion ground connection.

2. The brushless motor of claim 1, wherein the end of the rotation shaft is provided with a groove, a conductor is provided in the groove, and the discharge portion is inserted into the groove.

3. The brushless motor of claim 2, wherein a sealing ring is provided at an opening of the groove, and the discharge portion is inserted into the groove through the sealing ring.

4. The brushless electric machine of claim 3, wherein the discharge portion is provided in a needle shape, and a needle of the discharge portion is in contact with the conductor through the sealing ring.

5. The brushless electric machine of claim 1, wherein the discharge portion is configured in a ring shape, the rotating shaft is sleeved inside the discharge portion, and the conductor is disposed inside the discharge portion.

6. The brushless motor of claim 5, wherein a sealing ring is provided at an end of the discharge portion, and the rotation shaft is inserted into the conductor through the sealing ring.

7. The brushless electric machine of claim 1, wherein the discharge portion is connected to the housing, the discharge portion and the housing both being provided as conductors, the housing being grounded.

8. The brushless electric machine of claim 1, wherein the electrical conductors are provided as conductive grease.

9. The brushless electric machine of claim 1, wherein the brushless electric machine is configured as an inner rotor brushless electric machine, the brushless electric machine comprising a rotor and a stator, the stator comprising a housing and a magnet, the housing being secured to the housing, the magnet being secured inside the housing, the magnet being disposed inside the rotor.