CN110808653A

CN110808653A - Portable spindle motor

Info

Publication number: CN110808653A
Application number: CN201911275037.4A
Authority: CN
Inventors: 宁晓琪; 石甫明
Original assignee: BEIJING KND AUTOMATION TECHNOLOGY Co Ltd
Current assignee: BEIJING KND AUTOMATION TECHNOLOGY Co Ltd
Priority date: 2019-12-12
Filing date: 2019-12-12
Publication date: 2020-02-18

Abstract

The invention relates to a spindle motor (1) having a rotor (6) and a stator core (7), wherein the rotor (6) is mounted on a motor shaft (2) which is coaxially formed therewith, the spindle motor (1) further having a front end cap (3) and a rear end cap (4) which are mounted on the front and rear ends of the motor shaft (2), respectively, wherein the spindle motor (1) further has a housing (5), the housing (5) is formed in a hollow cylinder shape and is connected on the front and rear ends to the front end cap (3) and the rear end cap (4), respectively, and wherein the stator core (7) is fixed on the inner wall of the housing (5) in a rotationally fixed manner.

Description

Portable spindle motor

Technical Field

The invention relates to a spindle motor, in particular to a portable spindle motor.

Background

Spindle motors are also known as high speed motors, and generally refer to ac motors having a rotational speed in excess of 10000 rpm. The numerical control machining device is mainly applied to the field of numerical control machining, has the advantages of high rotating speed, small volume, light weight, low material consumption, low noise, low vibration and the like, and is increasingly paid attention to and applied by related industries. In the modern society with high-speed technological progress, the motor plays an important role in the industrial production process by the technical requirements which cannot be met by other common motors.

In the field of numerical control machine tools, with the market trend of high precision, high rotating speed, low noise and long service life of the numerical control machine tools, the main shaft motor in the numerical control machine tool is also required to have the characteristics of light weight, high precision, high rotating speed, low noise, long service life and the like. However, the conventional spindle motor is generally an inorganic shell type motor at present, i.e., a stator core is directly connected with front and rear end covers, and a heat dissipation air duct is arranged on the stator core. The main reasons are that the traditional spindle motor has high cost, low precision, large noise, low heat dissipation efficiency of the motor, short service life of the bearing and heavy weight.

Disclosure of Invention

In view of the disadvantages of the prior art, an object of the present invention is to provide a lightweight spindle motor, which has advantages of improved motor precision, improved motor heat dissipation efficiency, reduced motor noise, improved motor speed, and improved motor precision, and has wide versatility.

According to the invention, a spindle motor is provided, which has a rotor and a stator core, wherein the rotor is mounted on a motor shaft which is configured coaxially therewith, and the spindle motor further has a front end cap and a rear end cap which are arranged at the front and rear ends of the motor shaft, respectively. The spindle motor is characterized in that the spindle motor further comprises a housing which is hollow and cylindrical and is connected to the front end cap and the rear end cap at the front and rear ends, respectively, and the stator core is fixed on the inner wall of the housing in a non-rotatable manner.

Compared with the traditional spindle motor, the spindle motor provided by the invention is additionally provided with the shell, so that the stator core is not required to be directly connected with the front end cover and the rear end cover of the spindle motor and form a shell of the spindle motor, and in addition, a heat dissipation structure and the like are not required to be arranged on the stator core, so that the outer diameter of the stator core can be designed to be small enough, the integral weight of the motor is effectively reduced, and the cost of the motor is further reduced.

According to a preferred embodiment of the invention, the motor shaft is designed as a rotor shaft of the rotor, the rotor being rotatable in a rotationally fixed manner relative to the motor shaft, and the motor shaft being rotatably supported on the front and rear end covers by bearings at both ends of the motor shaft. The spindle motor is further provided with a bearing pressing plate, and the bearing pressing plate is fixed on the bearing chamber wall of the bearing at the front end cover through a threaded connection portion. Specifically, a shaft shoulder of the motor shaft is abutted against the end face of the bearing, the bearing is pressed tightly through the bearing pressing plate, and the bearing pressing plate is fixed on the bearing chamber wall of the bearing at the front end cover through the threaded connection part, so that the vibration of the bearing in the operation process is reduced, the service life of the bearing is prolonged, and the stability of the motor is improved; and the axial float of the motor shaft is effectively reduced, the axial precision of the motor shaft is improved, and the precision of the motor is further improved.

According to the invention, a plurality of radiating ribs are arranged on each side surface of the shell. Preferably, the heat dissipation ribs are configured in a groove shape and extend on each side of the casing in an axial direction. According to the invention, a plurality of heat dissipation air ducts are arranged in the housing. Preferably, the heat dissipation air duct is configured as a through hole penetrating the casing in an axial direction, and a vent of the heat dissipation air duct is not covered by the front end cover or the rear end cover. The shell is a hollow cylindrical structure with a middle cavity, can be sleeved outside the spindle motor to form a shell, and obviously improves the heat dissipation efficiency of the spindle motor by arranging the heat dissipation ribs on the outer surface of the shell and arranging the heat dissipation air duct inside the shell.

In addition, the spindle motor has a fan disposed behind the rear end cover in the axial direction, and the fan is covered by a fan cover. The fan is an actuating component of the heat dissipation device.

According to the invention, the casing is preferably directly connected with the front end cover and the rear end cover through threaded connection parts. Of course, other means of attachment are possible, such as by a snap-fit connection or by an adhesive connection. In addition, the casing is shrink-fitted on the outer wall of the stator core. Of course, other connection means are possible, such as a snap connection or an adhesive connection. The above-mentioned connection means and other connection means known in the art are all within the scope of the present invention. Here, stator core need not with front and back end cover lug connection, also need not surround whole motor as the shell yet, therefore stator core's external diameter can be as little as possible, as long as can with casing fastening connection can, show the weight that has reduced stator core from this, and then reduced whole spindle motor's weight.

According to the present invention, the casing, the front cover and the rear cover are all made of a lightweight material, and wherein the casing is formed by drawing, and the front cover and the rear cover are formed by casting.

According to a preferred embodiment of the invention, the front end cover, the rear end cover and the casing are all made of aluminum materials, so that the cost of the motor is reduced by reducing the steel material usage of the stator core, and meanwhile, the casing, the heat dissipation air duct and the heat dissipation ribs are all made of aluminum materials, so that the heat dissipation performance of the motor is effectively improved, the weight of the motor is reduced, the cost of the motor is reduced, the service life of a bearing is prolonged, the precision of the motor is improved, the noise is reduced and the like.

Drawings

The following detailed description of the preferred embodiments of the present invention is provided in conjunction with the accompanying drawings, and the following description is exemplary and not limiting, and any other similar cases are within the scope of the present invention. In the following detailed description, directional terms, such as "left", "right", "upper", "lower", "front", "rear", and the like, are used with reference to the orientation as illustrated in the drawings. Components of embodiments of the present invention can be positioned in a number of different orientations and the directional terminology is used for purposes of illustration and is in no way limiting. Wherein the various figures respectively show:

fig. 1 is a schematic perspective view of a spindle motor 1 according to the present invention;

fig. 2 is a sectional view of a spindle motor according to the present invention in an axial direction;

fig. 3 is a schematic perspective view of a housing of a spindle motor according to the present invention.

Detailed Description

Fig. 1 shows a schematic perspective view of a spindle motor 1 according to the present invention. According to the spindle motor 1 shown in fig. 1 having a motor shaft 2, the spindle motor 1 is provided with a front end cover 3, a housing 5 and a rear end cover 4 in this order as viewed in the axial direction of the motor shaft 2. The front cover 3 and the rear cover 4 are respectively supported on the motor shaft 2, and the housing 5 is respectively connected with the front cover 3 and the rear cover 4 through a threaded connection, such as a direct connection through screws. Downstream of the rear end cover 4 in the axial direction, a fan (not shown) can also be arranged as an actuating element for heat dissipation, which is surrounded by a fan housing 10. A motor junction box 11 for routing electrical cables is also provided at the rear end cover 4 and the fan housing 10.

Fig. 2 shows a sectional view of the spindle motor 1 according to the present invention in an axial direction, which clearly shows the internal structure of the spindle motor 1 according to the present invention. The spindle motor 1 has a rotor 6 and a stator core 7, wherein the rotor 6 is mounted on a motor shaft 2 that is coaxially formed therewith, and the spindle motor 1 further has a front end cap 3 and a rear end cap 4 that are respectively disposed at the front and rear ends of the motor shaft 2. The spindle motor 1 further has a housing 5, the housing 5 is fixedly connected to the front end cover 3 and the rear end cover 4 through screws at the front end and the rear end, respectively, and the stator core 7 is fixed on the inner wall of the housing 5 in a non-rotatable manner, wherein the axial length of the stator core 7 is smaller than the axial length of the housing 5. Because stator core need not with front and back end cover lug connection, also need not surround whole motor as the shell yet, consequently stator core's external diameter can be as little as possible, as long as can with the casing fastening connection can, show the weight that has reduced stator core from this, and then reduced whole spindle motor's weight.

Furthermore, the motor shaft 2 is designed as a rotor shaft of the rotor 6, the rotor 6 being rotatable in a rotationally fixed manner relative to the motor shaft 2. The motor shaft 2 is rotatably supported on the front cover 3 and the rear cover 4 by two bearings 9. In addition, the spindle motor 1 is further provided with a bearing pressing plate 8, the bearing pressing plate 8 is fixed on a bearing chamber wall of a bearing 9 of the front end cover 3 through screws, a shaft shoulder of the motor shaft 2 abuts against the end face of the bearing, and the bearing 9 is pressed tightly through the bearing pressing plate 8. The structure reduces the vibration of the bearing in the operation process, prolongs the service life of the bearing and improves the stability of the motor; and the axial float of the motor shaft is effectively reduced, the axial precision of the motor shaft is improved, and the precision of the motor is further improved.

Fig. 3 is a schematic perspective view of the housing 5 of the spindle motor 1 according to the present invention. As shown in the figure, the casing 5 is a hollow cylindrical structure, and a hollow cavity 12 is formed in the middle of the casing. A plurality of groove-shaped heat dissipation ribs 14 are provided on each side surface, here four side surfaces, of the housing 5. These heat dissipating ribs 14 extend in the axial direction from one end face to the other end face of the housing 5. Besides the heat dissipating ribs 14, a plurality of, here four, heat dissipating air ducts 13 are provided in the casing 5, the heat dissipating air ducts 13 are configured as through holes that penetrate the casing 5 in the axial direction, and are provided with ventilation openings on both sides, and as shown in fig. 1, the ventilation openings of the heat dissipating air ducts 13 are not covered by the front end cover 3 or the rear end cover 4. The shell is a hollow cylindrical structure with a middle cavity, can be sleeved outside the spindle motor to form a shell, and obviously improves the heat dissipation efficiency of the spindle motor by arranging the heat dissipation ribs on the outer surface of the shell and arranging the heat dissipation air duct inside the shell. In addition, a heat dissipation structure and the like do not need to be arranged on the stator core, so that the outer diameter of the stator core can be designed to be small enough, the whole weight of the motor is effectively reduced, and the cost of the motor is further reduced. In addition, threaded holes 15 for screw fastening are provided on both end faces of the housing 5.

The best mode of carrying out the invention is described in detail above with reference to the accompanying drawings. It should be understood by those skilled in the art that the drawings and their corresponding descriptions are merely for purposes of illustrating the invention and that other modifications, substitutions and alterations may be made by those skilled in the art based on the teachings herein. Such modifications, substitutions or improvements are intended to fall within the scope of the invention.

List of reference numerals:

1 spindle motor

2 Motor shaft

3 front end cover

4 rear end cover

5 casing

6 rotor

7 stator core

8 bearing pressure plate

9 bearing

10 fan cover

11 motor junction box

12 cavity

13 radiating air duct

14 heat dissipation rib

15 threaded holes.

Claims

1. A spindle motor (1) having a rotor (6) and a stator core (7), wherein the rotor (6) is mounted on a motor shaft (2) coaxially arranged therewith, the spindle motor (1) further having a front cover (3) and a rear cover (4) respectively arranged at the front and rear ends of the motor shaft (2),

characterized in that the spindle motor (1) further comprises a housing (5), wherein the housing (5) is configured as a hollow cylinder and is connected at the front and rear ends to the front end cover (3) and the rear end cover (4), respectively, and wherein the stator core (7) is fixed on the inner wall of the housing (5) in a rotationally fixed manner.

2. Spindle motor (1) according to claim 1, characterised in that the motor shaft (2) is configured as a rotor shaft of the rotor (6), the rotor (6) being rotatable in a rotationally fixed manner relative to the motor shaft (2).

3. Spindle motor (1) according to claim 1, characterised in that the front end cap (3) and the rear end cap (4) are connected with the housing (5) by a threaded connection.

4. Spindle motor (1) according to claim 3, characterised in that the spindle motor (1) further has a bearing pressure plate (8), the bearing pressure plate (8) being fixed on the bearing chamber wall of the bearing (9) of the front end cap (3) by means of a threaded connection.

5. A spindle motor (1) as claimed in any one of claims 1 to 4, characterised in that a plurality of heat dissipating ribs (14) are provided on each side of the housing (5).

6. Spindle motor (1) according to claim 5, characterised in that the heat dissipation ribs (14) are configured as grooves and extend in the axial direction on each side of the housing (5).

7. A spindle motor (1) as claimed in any one of claims 1 to 4, characterised in that a plurality of heat dissipation air ducts (13) are provided in the housing (5).

8. The spindle motor (1) according to claim 7, wherein the heat dissipation air duct (13) is configured as a through hole penetrating the housing (5) in an axial direction, and a ventilation opening of the heat dissipation air duct (13) is not covered by the front end cover (3) or the rear end cover (4).

9. Spindle motor (1) according to one of claims 1 to 4, characterized in that the spindle motor (1) further has a fan arranged behind the rear end cap (4) in the axial direction, which fan is covered by a fan cover (10).

10. Spindle motor (1) according to any of claims 1-4, characterized in that the housing (5), front cover (3) and rear cover (4) are all made of light material, and wherein the housing (5) is formed by drawing and the front cover (3) and rear cover (4) are formed by casting.