Brushless motor capable of reducing eccentric movement and special tool thereof

Abstract

The utility model discloses a brushless motor capable of reducing eccentric movement and a special tool thereof. Belongs to the technical field of brushless motors. The motor is characterized by comprising a rotor and a stator, the stator comprises a bearing seat, and bearings are fixedly arranged at the two ends of an inner hole of the bearing seat; the stator comprises a machine shell with a magnet on the inner side wall, a rotating shaft is arranged at the bottom of the machine shell in the axial direction through a shaft sleeve, and the rotating shaft is in interference fit with the bearing. A positioning part is arranged at one end of the rotating shaft connected with the shaft sleeve; the utility model aims to provide the brushless motor which is simple in structure, and the bearing and the shaft are matched in a centering manner to reduce eccentric movement, and the special tool of the brushless motor. The method is used for centering press-fitting of the brushless motor.

Description

Technical Field

[0001] The utility model relates to a brushless motor, and more specifically, to a brushless motor for reducing eccentric crosstalk and a special tooling therefor. Background Art

[0002] In the initial design, the shaft of the motor and the bearing are in clearance fit, and the bearing and the bearing housing are also in clearance fit. The bearing and the bearing housing are fixed first with anaerobic glue, and finally the outer rotor and the stator are fixed with a shaft retainer to assemble the whole machine. This design has crosstalk in the motor itself and eccentricity between the bearing and the shaft. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a brushless motor for reducing eccentric crosstalk and a special tooling therefor, which have a simple structure and the bearing and the shaft are in centering fit, aiming at the deficiencies of the above-mentioned prior art.

[0004] The technical solution of the utility model is realized as follows: A brushless motor for reducing eccentric crosstalk includes a rotor and a stator. The stator includes a bearing housing, and bearings are fixedly arranged at both ends of the inner hole of the bearing housing; the stator includes a casing with magnets provided on the inner side wall, and a rotating shaft is axially arranged through a shaft sleeve at the bottom of the casing, and the rotating shaft is in interference fit with the bearing; a positioning portion is provided at one end of the rotating shaft connected to the shaft sleeve.

[0005] In the above-mentioned brushless motor for reducing eccentric crosstalk, when the positioning portion cooperates with an external special tooling, the rotating shaft and the bearing are on the same axis.

[0006] In the above-mentioned brushless motor for reducing eccentric crosstalk, the positioning portion is integrally formed at one end of the rotating shaft outside the casing.

[0007] In the above-mentioned brushless motor for reducing eccentric crosstalk, the outer diameter of the rotating shaft is 5 - 15 μm larger than the inner diameter of the bearing.

[0008] In the above-mentioned brushless motor for reducing eccentric crosstalk, the distance between the end of the positioning portion and the outer surface of the shaft sleeve is 3 - 8 mm.

[0009] After the utility model adopts the above structure, the rotating shaft and the bearing are in close contact after interference fit, and it is not easy to have crosstalk during the operation of the motor, which can effectively ensure that the axes of the rotating shaft and the bearing are aligned and avoid eccentricity. At the same time, when press-fitting the rotor and the stator, the rotating shaft can be conveniently positioned through the positioning portion.

[0010] A special tooling for press-fitting the above-mentioned brushless motor, including a base, on which a positioning seat for placing the stator is provided, and a relief hole is provided along the axis on the positioning seat; a lifting assembly cooperating with an external servo press is provided on the base; a pressing head opposite to the positioning seat is provided on the lifting assembly, and a positioning groove cooperating with the positioning portion is provided on the pressing head; the positioning groove and the relief hole are arranged in alignment.

[0011] In the above-mentioned special tooling, the lifting assembly includes two lifting rods symmetrically arranged on the base on both sides of the positioning seat. A lifting seat is provided on the lifting rod through a sleeve, and the pressing head is arranged at the center of the bottom of the lifting seat; a limiting plate is provided at the top of each lifting rod; a connecting block for connecting with an external servo press is provided on the lifting seat.

[0012] In the above-mentioned special tooling, the pressing head includes an installation cylinder arranged on the lifting assembly. A pressing block is arranged in the installation cylinder, and the positioning groove is arranged at the bottom of the pressing block; an installation long hole is provided on the pressing block, and a screw hole cooperating with the installation long hole is provided on the installation cylinder. The installation long hole and the screw hole are cooperated through a fastening screw; a limiting ring cooperating with the bottom of the installation cylinder is provided on the pressing block, and a handle is provided on the limiting ring.

[0013] In the above-mentioned special tooling, a detachable first limiting column is provided vertically on the base, and a second limiting column corresponding to the first limiting column is detachably provided on the lifting assembly.

[0014] After the present utility model adopts the above structure, the stator is positioned and placed through the positioning seat, and the positioning groove is in positioning cooperation with the rotating shaft, so that the bearing on the stator and the rotating shaft are aligned. Then, the rotating shaft is pressed into the bearing through the lifting assembly. The whole press-fitting process is convenient and fast, and the center alignment is accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following further detailed description of the present utility model is given in conjunction with the embodiments in the drawings, but it does not constitute any limitation to the present utility model.

[0016] Figure 1 is a schematic structural diagram of the brushless motor of the present utility model;

[0017] Figure 2 is a schematic cross-sectional structural diagram of the brushless motor of the present utility model;

[0018] Figure 3 is a schematic structural diagram of the special tooling of the present utility model;

[0019] Figure 4 is a schematic cross-sectional structural diagram of the special tooling of the present utility model.

[0020] In the figure: 1, bearing housing; 2, bearing; 3, housing; 4, shaft sleeve; 5, rotating shaft; 6, positioning portion; 7, base; 8, positioning seat; 9, relief hole; 10, lifting assembly; 10a, lifting rod; 10b, sleeve; 10c, lifting seat; 10d, limiting plate; 10e, connecting block; 11, pressing head; 11a, mounting cylinder; 11b, pressing block; 11c, mounting long hole; 11d, screw hole; 11e, limiting ring; 11f, handle; 12, positioning groove; 13, first limiting post; 14, second limiting post. Specific implementation manner

[0021] Refer to Figure 1-2 As shown, a brushless motor for reducing eccentric runout of the present utility model includes a rotor and a stator. The stator includes a bearing housing 1, and bearings 2 are fixedly arranged at both ends of the inner hole of the bearing housing 1; the stator includes a housing 3 with magnets provided on the inner side wall, and a rotating shaft 5 is axially arranged at the bottom of the housing 3 through a shaft sleeve 4, and the rotating shaft 5 is in interference fit with the bearing 2; a positioning portion 6 is provided at one end of the rotating shaft 5 connected to the shaft sleeve 4. By performing interference fit with a rotating shaft having an outer diameter larger than the inner diameter of the bearing, the gap between the two is eliminated, which can effectively prevent the rotating shaft from running out during the operation of the motor and avoid eccentricity caused by axis deviation. By providing the positioning portion, it is convenient to use a tooling to cooperate with the rotating shaft for positioning when press-fitting the rotor and the stator.

[0022] In this embodiment, when the positioning portion 6 cooperates with an external special tooling, the rotating shaft 5 and the bearing 2 are on the same axis. Adopting this structure can quickly align the rotating shaft and the bearing.

[0023] In this embodiment, the positioning portion 6 is integrally formed at one end of the rotating shaft 5 outside the housing 3. The positioning portion is integrally formed on the rotating shaft, and there is no need to assemble the positioning portion separately, which is convenient and fast.

[0024] In this embodiment, the outer diameter of the rotating shaft 5 is 5 - 15 μm larger than the inner diameter of the bearing 2. When performing interference fit, the outer diameter of the rotating shaft and the inner diameter of the bearing should not be too large to avoid failure to fit smoothly. Through multiple attempts, it is found that the optimal diameter difference between the two is 5 - 15 μm.

[0025] In this embodiment, the distance between the end of the positioning portion 6 and the outer surface of the shaft sleeve 4 is 3 - 8 mm. In addition, the structure of the positioning portion can also be composed of a groove provided at the end of the rotating shaft.

[0026] During use, fix the bearings at both ends of the bearing housing, adopt the method of tube shaft press-fitting to align the rotating shaft and the bearing through the tooling, and then press the rotating shaft into the bearing to complete the assembly.

[0027] Refer to Figure 3-4As shown, the utility model is a special tool for press-fitting the brushless motor, comprising a base 7, on which a positioning seat 8 for placing the stator is provided, and a clearance hole 9 is provided on the positioning seat 8 along the axis; a lifting assembly 10 matched with an external servo press is provided on the base 7; a pressing head 11 opposite to the positioning seat 8 is provided on the lifting assembly 10, and a positioning groove 12 matched with the positioning portion 6 is provided on the pressing head 11; the positioning groove 12 is arranged in the center of the clearance hole 9. After the stator is placed on the positioning seat, the bearing and the clearance hole are located on the same central axis, the rotating shaft positioning portion is positioned and matched with the positioning groove, so that the bearing and the rotating shaft are aligned, and then the rotating shaft is pressed into the bearing through the lifting assembly, and the whole press-fitting process is convenient and fast, and the center alignment is accurate. And through the dynamic characteristics of the servo control of the external servo press, the whole press-fitting process can be accurately controlled to achieve high-precision assembly.

[0028] In this embodiment, the lifting assembly 10 includes two lifting rods 10a symmetrically arranged on the bases 7 on both sides of the positioning seat 8, a lifting seat 10c is arranged on the lifting rod 10a through a sleeve 10b, and the pressure head 11 is arranged at the bottom center of the lifting seat 10c; a limit plate 10d is arranged on the top of each lifting rod 10a; and a connecting block 10e for connecting to an external servo press is arranged on the lifting seat 10c. The two lifting rods are symmetrically arranged on both sides of the positioning seat to ensure that the lifting seat remains balanced when pressing down, so that the pressure is maintained at the center of the rotating shaft to prevent the rotating shaft from tilting.

[0029] In this embodiment, the pressure head 11 includes a mounting tube 11a disposed on the lifting assembly 10, a pressure block 11b is disposed in the mounting tube 11a, and the positioning groove 12 is disposed at the bottom of the pressure block 11b; a mounting long hole 11c is disposed on the pressure block 11b, and a screw hole 11d matching the mounting long hole 11c is disposed on the mounting tube 11a, and the mounting long hole 11c and the screw hole 11d are matched by a fastening screw; a limiting ring 11e matching the bottom of the mounting tube 11a is disposed on the pressure block 11b, and a handle 11f is disposed on the limiting ring 11e. After adopting this structure, when performing press-fitting, after the stator and the rotor are aligned and placed, the operator holds the shaft and presses the end of the shaft into the bearing first by the handle to fix it, so that the operator does not need to hold the shaft when pressing it in later by the servo press.

[0030] In this embodiment, a detachable first limiting column 13 is vertically provided on the base 7, and a detachable second limiting column 14 corresponding to the first limiting column 13 is detachably provided on the lifting assembly 10. The maximum descending distance of the lifting assembly is limited by the cooperation of the first limiting column and the second limiting column, so as to avoid the brushless motor being crushed by excessive downward pressure, and the first limiting column and the second limiting column of different lengths can be replaced according to the size of the processed motor to adapt to the press-fitting of motors of different sizes.

[0031] During use, after placing the stator on the positioning seat, positionally mate the rotating shaft positioning portion with the positioning groove so that the bearing and the rotating shaft are aligned. Then, drive the pressing head through an external servo press to press the rotating shaft into the bearing to complete the mating.

[0032] The above-described embodiments are preferred embodiments of the present invention, which are only used to conveniently illustrate the present invention and do not impose any form of limitation on the present invention. Any person with ordinary knowledge in the technical field, if within the scope not departing from the technical features of the present invention, makes local modifications or equivalent embodiments by using the technical content disclosed in the present invention, and does not depart from the technical feature content of the present invention, still fall within the scope of the technical features of the present invention.

Claims

1. A brushless motor with reduced eccentricity, comprising a rotor and a stator, characterized in that: The stator comprises a bearing seat (1), and bearings (2) are fixedly arranged at both ends of the inner hole of the bearing seat (1); the stator comprises a casing (3) with a magnet arranged on the inner wall, and a rotating shaft (5) is axially arranged at the bottom of the casing (3) through a shaft sleeve (4), and the rotating shaft (5) and the bearing (2) are interference fit; and a positioning portion (6) is provided at one end of the rotating shaft (5) connected to the shaft sleeve (4).

2. A brushless motor with reduced eccentricity according to claim 1, characterized in that: When the positioning portion (6) cooperates with the external special tooling, the rotating shaft (5) and the bearing (2) are located on the same axis.

3. A brushless motor with reduced eccentricity according to claim 1 or 2, characterized in that: The positioning portion (6) is integrally formed at one end of the rotating shaft (5) located outside the housing (3).

4. A brushless motor with reduced eccentricity according to claim 1, characterized in that: The outer diameter of the rotating shaft (5) is 5-15 μm larger than the inner diameter of the bearing (2).

5. A brushless motor with reduced eccentricity according to claim 1, characterized in that: The distance between the end of the positioning portion (6) and the outer surface of the shaft sleeve (4) is 3-8 mm.

6. A special tool for press-fitting the brushless motor according to any one of claims 3 to 5, comprising a base (7), characterized in that: The base (7) is provided with a positioning seat (8) for placing the stator, and a clearance hole (9) is provided on the positioning seat (8) along the axis; a lifting assembly (10) is provided on the base (7) for cooperating with an external servo press; a pressure head (11) is provided on the lifting assembly (10) opposite to the positioning seat (8), and a positioning groove (12) is provided on the pressure head (11) for cooperating with the positioning portion (6); the positioning groove (12) is arranged in alignment with the clearance hole (9).

7. A special tool according to claim 6, characterized in that: The lifting assembly (10) comprises two lifting rods (10a) symmetrically arranged on bases (7) on both sides of a positioning seat (8); a lifting seat (10c) is arranged on the lifting rod (10a) through a sleeve (10b); the pressure head (11) is arranged at the bottom center of the lifting seat (10c); a limit plate (10d) is arranged on the top of each lifting rod (10a); and a connecting block (10e) for connecting to an external servo press is arranged on the lifting seat (10c).

8. A special tool according to claim 6, characterized in that: The pressure head (11) comprises a mounting tube (11a) arranged on the lifting assembly (10), a pressure block (11b) is arranged in the mounting tube (11a), and the positioning groove (12) is arranged at the bottom of the pressure block (11b); a mounting long hole (11c) is arranged on the pressure block (11b), and a screw hole (11d) matching with the mounting long hole (11c) is arranged on the mounting tube (11a), and the mounting long hole (11c) and the screw hole (11d) are matched by a fastening screw; a limiting ring (11e) matching with the bottom of the mounting tube (11a) is arranged on the pressure block (11b), and a handle (11f) is arranged on the limiting ring (11e).

9. A special tool according to claim 6, characterized in that: A detachable first limiting column (13) is vertically provided on the base (7), and a detachable second limiting column (14) corresponding to the first limiting column (13) is detachably provided on the lifting assembly (10).

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