Convection type rotor inner-cooling electric spindle

Abstract

The invention discloses a convection type rotor inner-cooling motorized spindle which comprises a shell, a rotor shaft, a motor stator, a motor rotor and an air inlet impeller. Wherein the rotor shaft is connected in the shell in a rotating mode, the motor stator and the motor rotor are both installed between the shell and the rotor shaft, the motor stator is connected to the inner wall of the shell, the motor rotor is connected to the rotor shaft and located on the inner side of the motor stator, and the motor stator is connected to the rotor shaft and located on the inner side of the motor rotor. At least one air channel extending in the axial direction is formed in the motor rotor, the air inlet impeller is connected to the rotor shaft and located on one side of the motor rotor, and when the rotor shaft rotates, the air inlet impeller is driven to rotate, so that air is driven to flow into the air channel through the air inlet impeller. The cooling and heat dissipation efficiency of the motor rotor can be improved, the heat dissipation effect of the motor rotor is improved, and then the power of the motorized spindle can be improved.

Description

Technical Field

[0001] The invention relates to a convection type rotor inner cooling electric spindle. Background Art

[0002] At present, the electric spindle is a new technology that integrates the machine tool spindle and the spindle motor. It is widely used in the field of high-end CNC machine tools. For example, the Chinese patent with the announcement number CN208408557U discloses a permanent magnet high-speed electric spindle for drilling and tapping centers. The electric spindle is driven to rotate by the spindle motor. The spindle motor includes a motor stator connected to the housing and a motor rotor connected to the rotor shaft. Among them, the heat dissipation of the motor stator is relatively easy to achieve, while the heat dissipation of the motor rotor is very difficult. At present, the heat dissipation of the motor rotor is mainly achieved through the following two methods: one is to transfer the heat to the motor stator through the air gap between the motor stator and the motor rotor, and then the motor electronics conduct the heat to dissipate the heat; the other is to transfer the heat through the rotor shaft to the two ends of the rotor shaft for heat dissipation. However, the heat dissipation effect of the above two heat dissipation methods is not ideal, resulting in poor heat dissipation of the motor rotor, which seriously restricts the improvement of the power of the electric spindle. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a convection-type rotor internally cooled electric spindle, which can improve the cooling and heat dissipation efficiency of the motor rotor, improve the heat dissipation effect of the motor rotor, and thus help to increase the power of the electric spindle.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a convection type rotor inner cooling electric spindle, comprising a housing, a rotor shaft, a motor stator, a motor rotor and an air inlet impeller;

[0005] The rotor shaft is rotatably connected in the housing;

[0006] The motor stator and the motor rotor are both installed between the housing and the rotor shaft, the motor stator is connected to the inner wall of the housing, and the motor rotor is connected to the rotor shaft and is located on the inner side of the motor stator;

[0007] At least one air passage extending in the axial direction is provided in the motor rotor;

[0008] The air inlet impeller is connected to the rotor shaft and is located at one side of the motor rotor. When the rotor shaft rotates, the air inlet impeller is driven to rotate, and then the air is driven to flow into the air duct through the air inlet impeller.

[0009] Furthermore, the convection-type rotor internal cooling electric spindle further includes an exhaust impeller;

[0010] The exhaust impeller is connected to the rotor shaft, and the motor rotor is located between the air inlet impeller and the exhaust impeller. When the rotor shaft rotates, the exhaust impeller is driven to rotate, and the air flowing out of the air duct is discharged through the exhaust impeller.

[0011] Furthermore, an air inlet cavity and an air exhaust cavity are provided between the housing and the rotor shaft;

[0012] The air inlet cavity is arranged at one side of the air inlet impeller, the air inlet impeller is located between the air inlet cavity and the air passage, and the air inlet impeller is used to rotate with the rotor shaft and thus pump the air in the air inlet cavity into the air passage;

[0013] The exhaust chamber is arranged at one side of the exhaust impeller, and the exhaust impeller is located between the exhaust chamber and the air passage. The exhaust impeller is used to rotate with the rotor shaft and thus pump the air flowing out of the air passage into the exhaust chamber.

[0014] Furthermore, the shell is provided with an air inlet hole connected to the air inlet cavity, and the shell is provided with an exhaust hole connected to the exhaust cavity.

[0015] Furthermore, a plurality of the air inlet holes and the air outlet holes are respectively distributed in sequence along the circumference of the shell.

[0016] Furthermore, the motor stator includes a stator core connected to the inner wall of the shell and a stator winding connected to the stator core, the air inlet impeller is located on the inner side of one end of the stator winding, and the air exhaust impeller is located on the inner side of the other end of the stator winding.

[0017] Further, the motor rotor includes a rotor core and a pressure plate;

[0018] The rotor core and the pressure plate are both connected to the rotor shaft and located between the air inlet impeller and the air exhaust impeller;

[0019] There are two pressure plates, the rotor core is located between the two pressure plates, and the air passage runs through the two pressure plates and the rotor core.

[0020] Furthermore, the rotor core includes a plurality of stacked silicon steel sheets.

[0021] Furthermore, the air inlet impeller and the air exhaust impeller respectively include a mounting ring portion for connecting to the rotor shaft and a plurality of blade portions connected to the mounting ring portion and sequentially arranged along the circumference of the mounting ring portion.

[0022] Furthermore, a plurality of air passages are sequentially distributed along the circumferential direction of the motor rotor.

[0023] After adopting the above technical scheme, the motor rotor can drive the rotor shaft to rotate at a high speed, and the rotor shaft can drive the air intake impeller to rotate at a high speed. When the air intake impeller rotates at a high speed, it will draw air and drive the air to flow into the air duct. In the process of flowing through the air duct, the air can forcibly take away the heat of the motor rotor, and then perform forced convection cooling on the motor rotor, thereby achieving high-efficiency heat dissipation of the motor rotor, improving the heat dissipation efficiency of the motor rotor, and improving the heat dissipation effect of the motor rotor, which is beneficial to increasing the power of the electric spindle. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a convection-type rotor internal cooling electric spindle of the present invention;

[0025] Figure 2 for Figure 1 Detailed drawings of the parts;

[0026] Figure 3 It is a schematic structural diagram of the air inlet impeller and the air exhaust impeller of the present invention. DETAILED DESCRIPTION

[0027] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0028] like Figures 1 to 3 As shown, a convection type rotor inner cooling electric spindle comprises a housing 1, a rotor shaft 2, a motor stator 3, a motor rotor 4 and an air inlet impeller 5;

[0029] The rotor shaft 2 is rotatably connected in the housing 1;

[0030] The motor stator 3 and the motor rotor 4 are both installed between the housing 1 and the rotor shaft 2, the motor stator 3 is connected to the inner wall of the housing 1, and the motor rotor 4 is connected to the rotor shaft 2 and is located on the inner side of the motor stator 3;

[0031] The motor rotor 4 is provided with at least one air passage 6 extending in the axial direction;

[0032] The air inlet impeller 5 is connected to the rotor shaft 2 and is located on one side of the motor rotor 4. When the rotor shaft 2 rotates, the air inlet impeller 5 is driven to rotate, and then the air is driven to flow into the air passage 6 through the air inlet impeller 5. Specifically, the motor rotor 4 can drive the rotor shaft 2 to rotate at a high speed, and the rotor shaft 2 can drive the air inlet impeller 5 to rotate at a high speed. When the air inlet impeller 5 rotates at a high speed, it will pump air and then drive the air to flow into the air passage 6. In the process of flowing through the air passage 6, the air can forcibly take away the heat of the motor rotor 4, and then force convection cooling of the motor rotor 4, so as to achieve high-efficiency heat dissipation of the motor rotor 4, improve the heat dissipation efficiency of the motor rotor 4, and improve the heat dissipation effect of the motor rotor 4, which is conducive to improving the power of the electric spindle.

[0033] like Figures 1 to 3 As shown, the convection type rotor inner cooling electric spindle may further include an exhaust impeller 7;

[0034] The exhaust impeller 7 is connected to the rotor shaft 2, and the motor rotor 4 is located between the air inlet impeller 5 and the exhaust impeller 7. When the rotor shaft 2 rotates, it drives the exhaust impeller 7 to rotate and then discharges the air flowing out of the air duct 6 through the exhaust impeller 7.

[0035] like Figure 1 , 2 As shown, an air inlet cavity 8 and an air exhaust cavity 9 may also be provided between the housing 1 and the rotor shaft 2;

[0036] The air inlet cavity 8 is provided at one side of the air inlet impeller 5, and the air inlet impeller 5 is located between the air inlet cavity 8 and the air passage 6. The air inlet impeller 5 is used to rotate with the rotor shaft 2 and thus pump the air in the air inlet cavity 8 into the air passage 6;

[0037] The exhaust chamber 9 is arranged on one side of the exhaust impeller 7 , and the exhaust impeller 7 is located between the exhaust chamber 9 and the air duct 6 . The exhaust impeller 7 is used to rotate with the rotor shaft 2 and thereby pump the air flowing out of the air duct 6 into the exhaust chamber 9 .

[0038] like Figure 1 , 2As shown, the housing 1 is provided with an air inlet 10 connected to the air inlet cavity 8, and the housing 1 is provided with an exhaust hole 11 connected to the exhaust cavity 9; wherein, the air inlet 10 and the exhaust hole 11 are respectively distributed in a plurality along the circumference of the housing 1. Specifically, the rotation speed of the rotor shaft 2 can reach 24000rpm, thereby driving the air inlet impeller 5 and the exhaust impeller 7 to rotate at a high speed to generate forced convection air. Under the pumping action of the air inlet impeller 5 and the exhaust impeller 7, the air flows through the air inlet 10, the air inlet cavity 8, the air inlet impeller 5, the air duct 6, the exhaust impeller 7, the exhaust cavity 9 and the exhaust hole 11 in sequence, and the air can cool and dissipate the heat of the motor rotor 4 when flowing through the air duct 6, thereby achieving a better heat dissipation effect. In this embodiment, the air inlet impeller 5 and the exhaust impeller 7 are both made by integral precision casting.

[0039] like Figure 1 , 2 As shown, the motor stator 3 may include a stator core 12 connected to the inner wall of the housing 1 and a stator winding 13 connected to the stator core 12, the air inlet impeller 5 is located on the inner side of one end of the stator winding 13, and the air exhaust impeller 7 is located on the inner side of the other end of the stator winding 13.

[0040] like Figure 1 , 2 As shown, the motor rotor 4 may include a rotor core 14 and a pressure plate 15;

[0041] The rotor core 14 and the pressure plate 15 are both connected to the rotor shaft 2 and are located between the air inlet impeller 5 and the air outlet impeller 7;

[0042] Two pressure plates 15 are provided, the rotor core 14 is located between the two pressure plates 15 , and the air passage 6 runs through the two pressure plates 15 and the rotor core 14 .

[0043] In this embodiment, the rotor core 14 includes a plurality of stacked silicon steel sheets; specifically, the silicon steel sheets are made of high magnetic permeability material, and the cross-sectional area of ​​the silicon steel sheets can be redundant for the opening of the air channel 6, so the magnetic permeability requirements can still be met after the air channel 6 is opened.

[0044] like Figure 3 As shown, the air inlet impeller 5 and the air exhaust impeller 7 may respectively include a mounting ring portion 16 for connecting to the rotor shaft 2 and a plurality of blade portions 17 connected to the mounting ring portion 16 and arranged in sequence along the circumference of the mounting ring portion 16 .

[0045] Specifically, a plurality of air passages 6 are sequentially distributed along the circumference of the motor rotor 4 . In the present embodiment, a total of 12 air passages 6 are provided, and it is more appropriate that the total cross-sectional area of ​​the air passages 6 accounts for 15% to 20% of the total magnetic conductive area of ​​the motor rotor 4 .

[0046] In this embodiment, the air inlet impeller 5 and the air exhaust impeller 7 are both arranged on the inner side of the shell 1, utilizing the space inside the shell 1 without increasing the volume, and the overall structure is simple, easy to install and rotate, and highly reliable.

[0047] Specifically, a mounting hole for mounting a tool handle 18 is provided at the end of the rotor shaft 2, and a tool rod 19 is provided on the inner side of the rotor shaft 2. One end of the tool rod 19 is connected to a tapered pulling claw 20 for grasping the tool handle 18 in the mounting hole, and the other end of the tool rod 19 is connected to a tool changing cylinder 21, which is connected to one end of the housing 1 and is used to drive the tool rod 19 to move.

[0048] More specifically, the convection-type rotor internal cooling electric spindle of the embodiment of the present application can be used in high-end CNC grinding machines. The motor stator 3 can use mature external heat dissipation, and the motor rotor 4 dissipates heat through the air duct, thereby increasing the power of the electric spindle by about 40%.

[0049] To sum up, the motor rotor 4 can drive the rotor shaft 2 to rotate at high speed, and the rotor shaft 2 can drive the air inlet impeller 5 to rotate at high speed. When the air inlet impeller 5 rotates at high speed, it will pump air and drive the air to flow into the air duct 6. In the process of flowing through the air duct 6, the air can forcibly take away the heat of the motor rotor 4, and then perform forced convection cooling on the motor rotor 4, thereby achieving high-efficiency heat dissipation of the motor rotor 4, improving the heat dissipation efficiency of the motor rotor 4, and improving the heat dissipation effect of the motor rotor 4, which is beneficial to increasing the power of the electric spindle.

[0050] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A convection type rotor inner cooling electric spindle, characterized in that: It comprises a housing (1), a rotor shaft (2), a motor stator (3), a motor rotor (4) and an air inlet impeller (5); The rotor shaft (2) is rotatably connected in the housing (1); The motor stator (3) and the motor rotor (4) are both installed between the housing (1) and the rotor shaft (2); the motor stator (3) is connected to the inner wall of the housing (1); and the motor rotor (4) is connected to the rotor shaft (2) and is located on the inner side of the motor stator (3); The motor rotor (4) is provided with at least one air passage (6) extending in the axial direction; The air inlet impeller (5) is connected to the rotor shaft (2) and is located on one side of the motor rotor (4); when the rotor shaft (2) rotates, the air inlet impeller (5) is driven to rotate, and the air is driven to flow into the air duct (6) through the air inlet impeller (5).

2. The convection-type rotor inner cooling electric spindle according to claim 1, characterized in that: Also includes an exhaust impeller (7); The exhaust impeller (7) is connected to the rotor shaft (2), and the motor rotor (4) is located between the air inlet impeller (5) and the exhaust impeller (7). When the rotor shaft (2) rotates, the exhaust impeller (7) is driven to rotate, and the air flowing out of the air duct (6) is discharged through the exhaust impeller (7).

3. The convection-type rotor inner cooling electric spindle according to claim 2, characterized in that: An air intake chamber (8) and an air exhaust chamber (9) are also provided between the housing (1) and the rotor shaft (2); The air inlet cavity (8) is arranged on one side of the air inlet impeller (5), the air inlet impeller (5) is located between the air inlet cavity (8) and the air duct (6), and the air inlet impeller (5) is used to rotate along with the rotor shaft (2) and thereby pump air in the air inlet cavity (8) into the air duct (6); The exhaust chamber (9) is arranged on one side of the exhaust impeller (7), and the exhaust impeller (7) is located between the exhaust chamber (9) and the air duct (6). The exhaust impeller (7) is used to rotate with the rotor shaft (2) and thereby pump the air flowing out of the air duct (6) into the exhaust chamber (9).

4. The convection-type rotor inner cooling electric spindle according to claim 3, characterized in that: The shell (1) is provided with an air inlet hole (10) communicating with the air inlet cavity (8), and the shell (1) is provided with an air exhaust hole (11) communicating with the air exhaust cavity (9).

5. The convection-type rotor inner cooling electric spindle according to claim 4, characterized in that: A plurality of the air inlet holes (10) and the air outlet holes (11) are respectively distributed in sequence along the circumference of the shell (1).

6. The convection-type rotor inner cooling electric spindle according to claim 2, characterized in that: The motor stator (3) comprises a stator core (12) connected to the inner wall of the housing (1) and a stator winding (13) connected to the stator core (12); the air inlet impeller (5) is located on the inner side of one end of the stator winding (13); and the air outlet impeller (7) is located on the inner side of the other end of the stator winding (13).

7. The convection-type rotor inner cooling electric spindle according to claim 2, characterized in that: The motor rotor (4) comprises a rotor core (14) and a pressure plate (15); The rotor core (14) and the pressure plate (15) are both connected to the rotor shaft (2) and are located between the air inlet impeller (5) and the air outlet impeller (7); Two pressure plates (15) are provided, the rotor core (14) is located between the two pressure plates (15), and the air passage (6) runs through the two pressure plates (15) and the rotor core (14).

8. The convection-type rotor inner cooling electric spindle according to claim 7, characterized in that: The rotor core (14) comprises a plurality of stacked silicon steel sheets.

9. The convection-type rotor inner cooling electric spindle according to claim 2, characterized in that: The air inlet impeller (5) and the air exhaust impeller (7) respectively comprise a mounting ring portion (16) for connecting to the rotor shaft (2) and a plurality of blade portions (17) connected to the mounting ring portion (16) and arranged in sequence along the circumferential direction of the mounting ring portion (16).

10. The convection-type rotor inner cooling electric spindle according to claim 1, characterized in that: A plurality of air passages (6) are sequentially distributed along the circumference of the motor rotor (4).

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