High-speed motor spindle planetary gear support device and its support method

Abstract

The present invention discloses a planetary wheel support device for a high-speed motor spindle and its support method, which includes a housing, a rotating shaft, and at least three planetary rollers. The planetary rollers are arranged circumferentially around the rotating shaft as the center. The support method includes: a. forming an axial thrust support between the planetary rollers and the rotating shaft; b. designing the outer diameter of the planetary rollers to output the bearing speed of the planetary rollers; c. designing the distribution of the planetary rollers acting on the rotating shaft; d. designing the force exerted by the planetary rollers on the rotating shaft; e. designing the force exerted by the planetary rollers on the rotating shaft perpendicular to the axis direction of the rotating shaft. In the present invention, at least three planetary rollers are arranged around the rotating shaft at the original bearing position of the rotating shaft to replace the bearing, so as to exert a force perpendicular to the axis direction of the rotating shaft on the rotating shaft, providing a stable radial support for the rotating shaft, and at the same time being able to play an axial thrust role, which can greatly improve the rotating speed and load-bearing capacity of the rotating shaft.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-speed motor spindle support, and particularly relates to a planetary gear support device for a high-speed motor spindle and a support method thereof. Background Art

[0002] High-speed motors have the advantages of small volume, small moment of inertia, compact structure, large energy density, etc., and are thus widely used in industries such as industry, medical treatment, automobiles, and aerospace. As Figure 1 shown, the prior art uses a bearing b to support a high-speed rotor a. However, the bearing that provides a supporting effect for the high-speed rotor in the motor has become the main obstacle affecting the development of high-speed motors.

[0003] Currently, the bearings widely used in high-speed motors are four types: precision metal bearings, precision ceramic ball bearings, hydrostatic and hydrodynamic air bearings, and magnetic bearings. The first two are contact-type ball bearings with traditional mechanical structures, and the latter two are shaft-suspension non-contact bearings. In order to pursue the ultimate speed, although traditional ball bearings have made very great progress in materials and precision in recent years, due to the limitations of the structural principle, the application of ball bearings in the field of high-speed motors is restricted by processing and assembly accuracy, the ultimate speed of the bearings, lubrication methods, etc., and has become the biggest bottleneck for the motor to achieve ultra-high speed. Although technologies such as hydrostatic and hydrodynamic air suspension bearings and magnetic bearings that have emerged in recent years are not restricted by the rotational speed of traditional ball bearings, the supporting force that such non-contact bearings can provide is very limited, and the main shaft cannot bear large loads radially and axially, nor can it bear vibrations with large accelerations. Summary of the Invention

[0004] The purpose of the present invention is to solve the above-mentioned deficiencies existing in the prior art, and provide a planetary gear support device for a high-speed motor spindle and a support method thereof. At the position where a bearing is originally provided on the rotating shaft, at least three planetary rollers are arranged around the rotating shaft as the center to replace the bearing, so as to apply a force perpendicular to the axis direction of the rotating shaft to the rotating shaft, providing a stable radial support for the rotating shaft, and at the same time being able to play an axial thrust role, greatly improving the rotational speed and load-bearing capacity of the rotating shaft; using planetary rollers to reduce the rotational speed of the bearings of the planetary rollers, greatly reducing the bearing speed load and processing difficulty of the planetary rollers, making it possible to replace the original high-grade precision bearings with ordinary-grade bearings; and having the characteristics of simple structure, convenient manufacturing, and low cost.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] Planetary gear support device for high-speed motor spindle, including a housing and a rotating shaft, the rotating shaft is installed in the housing; characterized in that: it further includes at least three planetary rollers installed on the housing, and the planetary rollers are arranged circumferentially around the rotating shaft as the center. At the original bearing position of the rotating shaft, at least three planetary rollers are arranged around the rotating shaft as the center to replace the bearing, so as to apply a force perpendicular to the axis direction of the rotating shaft to the rotating shaft, providing a stable radial support for the rotating shaft, which can greatly improve the rotational speed and load-bearing capacity of the rotating shaft, and has the characteristics of simple structure, convenient manufacturing and low cost.

[0007] Further, the planetary rollers above the rotating shaft are movable on the housing, and the planetary rollers below the rotating shaft are fixed on the housing, so that multiple planetary rollers provide a more stable radial support for the rotating shaft.

[0008] Further, the housing is provided with a mounting hole perpendicular to the axis direction of the rotating shaft, and an elastic tensioner is movably connected in the mounting hole. The elastic tensioner applies a pre-tightening force to the upper planetary roller, so that the upper planetary roller presses against the rotating shaft. The elastic tensioner of the present invention is generally divided into a connecting part and an elastic part. The elastic part is made of an elastic material. The ways to apply a pre-tightening force to the upper planetary roller can be: (1) The mounting hole is a hole with a smooth inner wall. A downward force is applied to the elastic tensioner through a pushing structure. The elastic tensioner moves downward, so that the elastic part acts on the upper planetary roller and deforms, and then a pre-tightening force can be applied to the upper planetary roller, making the upper planetary roller firmly press on the rotating shaft; (2) The mounting hole is designed as a threaded hole, and the connecting part of the elastic tensioner is also provided with a thread. The connecting part is threadedly connected in the mounting hole. By screwing the connecting part, the elastic tensioner moves downward, and the elastic part acts on the upper planetary roller and deforms, and then a pre-tightening force can be applied to the upper planetary roller, making the upper planetary roller firmly press on the rotating shaft. Through the above structure, the rotating shaft can be restricted to rotate between the angles of multiple rollers, so that multiple planetary rollers provide a more stable radial support for the rotating shaft.

[0009] Further, since it is necessary to fix the planetary rollers in the housing, bearings are provided at both the front and rear ends of the planetary rollers of the present invention. At the same time, bearing holes corresponding to the bearings are provided in the housing. The bearing on the lower planetary roller matches the lower bearing hole, that is, the outer surface of the bearing on the lower planetary roller fits against the inner side of the bearing hole. There is a movable gap between the bearing on the upper planetary roller and the upper bearing hole. The elastic tensioner applies a pre-tightening force to the bearing on the upper planetary roller, so that the node where the elastic tensioner applies a pre-tightening force to the planetary roller is set inside the housing, playing a protective role, making the elastic tensioner apply a pre-tightening force to the planetary roller reliable and safe. The width of the planetary roller of the present invention can be freely set according to the working conditions.

[0010] Furthermore, the outer diameter of the planetary roller (designated as N) is greater than the outer diameter of the rotating shaft (designated as D). The ratio between the outer diameter N of the planetary roller and the outer diameter D of the rotating shaft determines the ratio of the rotating speed of the rotating shaft to the rotating speed of the planetary roller bearing. The reduction ratio calculation formula is N / D = P. When the rotating speed of the rotating shaft is constant and the outer diameter of the rotating shaft is constant, the larger the P value, the lower the rotating speed of the planetary roller bearing. For example, if the rotating speed of the rotating shaft of a high-speed motor is designed to be 120000 rpm, the outer diameter of the rotating shaft is 15 mm, and the outer diameter of the planetary roller is 75 mm, then the calculated P value is 5, and it is obtained that the rotating speed of the roller support bearing is only 24000 rpm, greatly reducing the rotating speed load and processing difficulty of the roller support bearing, making it possible to replace the original high-grade precision bearing with an ordinary-grade bearing.

[0011] Furthermore, the planetary rollers are circumferentially distributed on the rotating shaft in the same plane. The number of planetary rollers arranged below the rotating shaft is at least two, and the included angle between the two planetary rollers below the rotating shaft is greater than 0 degrees and less than 180 degrees, achieving the effects of simple structure and convenient manufacturing.

[0012] Furthermore, three planetary rollers are circumferentially distributed on the rotating shaft in the same plane, and the sizes of the three planetary rollers are the same, and the included angle between two planetary rollers is 120 degrees. When the rotating speed of the rotating shaft is low and the limit rotating speed of the planetary roller bearing is high, and there is a surplus of P value, generally, three planetary rollers on the same support surface are taken as a group. In order to pursue the maximum P value, the three rollers generally adopt a circumferential 120-degree uniform distribution. The sizes of the three planetary rollers are the same, and the maximum P value of 6.45 can be obtained when the three planetary rollers with the same size are uniformly distributed at 120 degrees in the same plane.

[0013] When the rotating speed of the rotating shaft is high and the limit rotating speed of the planetary roller bearing is low, and the P value is insufficient, different support surfaces can be selected and the diameter of the planetary roller can be increased to increase the P value, that is, the planetary roller is not supported on the rotating shaft in one plane, and theoretically an infinite P value can be obtained.

[0014] Furthermore, an axial thrust support is formed between the planetary roller and the rotating shaft to limit the axial movement of the rotating shaft.

[0015] Furthermore, the axial thrust support methods are specifically divided into cylindrical planetary rollers, stepped planetary rollers, conical planetary rollers, wedge-shaped planetary rollers, and arc planetary rollers. Specifically:

[0016] (1) Cylindrical planetary roller: A convex roller thrust surface is provided at the edge of the planetary roller. The roller thrust surface can be provided on both sides or only on one side. A convex rotating shaft thrust surface is provided at the edge of the rotating shaft. The roller thrust surface and the rotating shaft thrust surface are in contact to provide a one-way thrust function for the rotating shaft.

[0017] (2) Step planetary roller: A roller thrust surface in a stepped shape is provided at the edge of the planetary roller, and a rotating shaft thrust surface that matches the stepped roller thrust surface is provided at the edge of the rotating shaft. The roller thrust surface and the rotating shaft thrust surface are in contact to provide a unidirectional thrust function to the rotating shaft.

[0018] (3) Conical planetary roller: The shape of the planetary roller is designed as a conical shape. The outer surface of the planetary roller serves as the roller conical surface. A first convex portion in a conical shape is provided at the edge of the rotating shaft, and the outer surface of the first convex portion serves as the rotating shaft conical surface. The taper of the roller conical surface is opposite to the taper of the rotating shaft conical surface. The roller conical surface and the rotating shaft conical surface cooperate with each other. There is no need for a special thrust surface between the planetary roller and the rotating shaft to provide a unidirectional thrust function to the rotating shaft.

[0019] (4) Wedge-shaped planetary roller: There is a wedge-shaped limit connection between the planetary roller and the rotating shaft. A wedge-shaped groove can be provided on the planetary roller, and a protrusion is provided on the rotating shaft to form a wedge shape so that the protrusion on the rotating shaft matches the groove on the planetary roller; or a wedge-shaped groove is provided on the rotating shaft, and a protrusion is provided on the planetary roller to form a wedge shape so that the protrusion on the planetary roller matches the groove on the rotating shaft. There is no need for a special thrust surface between the planetary roller and the rotating shaft to provide a bidirectional thrust function to the rotating shaft.

[0020] (5) Arc planetary roller: The planetary roller is provided with a first arc surface, and the rotating shaft is provided with a second arc surface that is opposite to the first arc surface. The second arc surface and the first arc surface cooperate with each other. There is no need for a special thrust surface between the planetary roller and the rotating shaft to provide a bidirectional thrust function to the rotating shaft.

[0021] The supporting method of the high-speed motor spindle planetary gear supporting device is characterized by including the following steps:

[0022] a. Design the shape of the planetary roller, and design the shape of the rotating shaft according to the shape of the planetary roller so that an axial thrust support is formed between the planetary roller and the rotating shaft to limit the axial movement of the rotating shaft.

[0023] b. Design the outer diameter of the planetary roller and output the bearing speed of the planetary roller: Set the outer diameter of the planetary roller as N and the outer diameter of the rotating shaft as D. The ratio between the outer diameter N of the planetary roller and the outer diameter D of the rotating shaft determines the ratio of the rotating shaft speed to the bearing speed of the planetary roller. According to the reduction ratio calculation formula P = N / D, when the outer diameter D of the rotating shaft is constant, adjust the value of the outer diameter N of the planetary roller, and output the bearing speed of the planetary roller through the constant rotating shaft speed.

[0024] c. Design the distribution of the planetary rollers acting on the rotating shaft: When ensuring that the reduction ratio P value is sufficient, design three planetary rollers to be circumferentially distributed on the rotating shaft in the same plane. The sizes of the three planetary rollers are the same, and the three planetary rollers are evenly distributed at 120 degrees circumferentially.

[0025] d. Design the force exerted by the planetary rollers on the rotating shaft: One planetary roller above the rotating shaft is designed to be movable on the housing. Install the bearing on the upper planetary roller into the upper bearing hole, and there is a movable gap between the two. At the same time, the two planetary rollers below the rotating shaft are designed to be fixed on the housing, and the bearings on the lower planetary rollers are limited to the lower bearing holes.

[0026] e. The planetary rollers exert a force perpendicular to the axis direction of the rotating shaft on the rotating shaft: Install an elastic tensioner in the mounting hole perpendicular to the axis direction of the rotating shaft on the housing, and then apply a downward force to the elastic tensioner in the mounting hole. The elastic tensioner applies a pre-tightening force to the upper planetary roller, causing the upper planetary roller to move vertically downward, so that the three planetary rollers press on the rotating shaft.

[0027] Due to the adoption of the above technical solutions, the present invention has the following beneficial effects:

[0028] 1. In the present invention, at the original bearing position of the rotating shaft, at least three planetary rollers are arranged around the rotating shaft as the center to replace the bearing to exert a force perpendicular to the axis direction of the rotating shaft, providing a stable radial support for the rotating shaft, which can greatly improve the rotational speed and load-bearing capacity of the rotating shaft, and has the characteristics of simple structure, convenient manufacturing, and low cost.

[0029] 2. In the present invention, the planetary roller above the rotating shaft is movable on the housing, and at the same time, the planetary rollers below the rotating shaft are fixed on the housing, so that multiple planetary rollers provide a more stable radial support for the rotating shaft.

[0030] 3. The outer diameter of the planetary roller (the outer diameter of the planetary roller is defined as N) is larger than the outer diameter of the rotating shaft (the outer diameter of the rotating shaft is defined as D). The ratio between the outer diameter N of the planetary roller and the outer diameter D of the rotating shaft determines the ratio of the rotational speed of the rotating shaft to the rotational speed of the planetary roller bearing. The reduction ratio calculation formula is N / D = P. When the rotational speed of the rotating shaft is constant and the outer diameter of the rotating shaft is constant, the larger the P value, the lower the rotational speed of the planetary roller bearing. For example, if the rotational speed of the rotating shaft of a high-speed motor is designed to be 120000 rpm, the outer diameter of the rotating shaft is 15 mm, and the outer diameter of the planetary roller is 75 mm, then the calculated P value is 5, and the rotational speed of the roller support bearing is only 24000 rpm, greatly reducing the rotational speed load and processing difficulty of the roller support bearing, making it possible to replace the original high-grade precision bearing with an ordinary-grade bearing.

[0031] 4. An axial thrust support is formed between the planetary roller and the rotating shaft of the present invention to limit the axial movement of the rotating shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be further described below in conjunction with the drawings:

[0033] Figure 1 is a structural schematic diagram of the prior art;

[0034] Figure 2 is a structural schematic diagram of the planetary gear support device for the high-speed motor main shaft in the present invention;

[0035] Figure 3 is a structural schematic diagram of the elastic tensioner applying a pre-tightening force to the bearing on the planetary roller in the present invention;

[0036] Figure 4 is a structural schematic diagram of the planetary rollers circumferentially distributed on the rotating shaft in the same plane in the present invention;

[0037] Figure 5 is a structural schematic diagram of the planetary rollers distributed on the rotating shaft in different planes in the present invention;

[0038] Figure 6 is a partial structural schematic diagram of the planetary rollers distributed on the rotating shaft in different planes in the present invention;

[0039] Figure 7 is a structural schematic diagram of the planetary roller in the present invention;

[0040] Figure 8 is Figure 7 the left view of;

[0041] Figure 9 is a structural schematic diagram of the rotating shaft in the present invention;

[0042] Figure 10 is a structural schematic diagram of three identical-sized planetary rollers circumferentially distributed on the rotating shaft in the same plane in the present invention;

[0043] Figure 11 is a structural schematic diagram of three different-sized planetary rollers circumferentially distributed on the rotating shaft in the same plane in the present invention;

[0044] Figure 12 is a structural schematic diagram of the elastic tensioner applying a pre-tightening force to one planetary roller above in the present invention;

[0045] Figure 13 is a structural schematic diagram of the elastic tensioner applying a pre-tightening force to two planetary rollers above in the present invention;

[0046] Figure 14Schematic diagram of the axial thrust support mode using cylindrical planetary rollers in the present invention;

[0047] Figure 15 Schematic diagram of the axial thrust support mode using stepped planetary rollers in the present invention;

[0048] Figure 16 Schematic diagram of the axial thrust support mode using conical planetary rollers in the present invention;

[0049] Figure 17 Schematic diagram of the axial thrust support mode using wedge-shaped planetary rollers in the present invention;

[0050] Figure 18 Schematic diagram of the axial thrust support mode using arc-shaped planetary rollers in the present invention.

[0051] In the figure, 1 - rotating shaft; 2 - housing; 3 - elastic tensioner; 4 - mounting hole; 5 - planetary roller; 6 - bearing; 7 - roller thrust surface; 8 - rotating shaft thrust surface. Specific implementation mode

[0052] As Figures 2 to 18 shown, it is a planetary gear support device for the high-speed motor spindle of the present invention, including a housing 2 and a rotating shaft 1, and the rotating shaft 1 is installed in the housing 2.

[0053] The present invention further includes at least three planetary rollers 5 installed on the housing 2, and the planetary rollers 5 are arranged circumferentially around the rotating shaft 1 as the center. At the original bearing position of the rotating shaft 1, at least three planetary rollers 5 are arranged around the rotating shaft 1 as the center to replace the bearing, so as to apply a force perpendicular to the axis direction of the rotating shaft 1 to the rotating shaft 1, providing a stable radial support for the rotating shaft 1, which can greatly improve the rotation speed and load-bearing capacity of the rotating shaft 1, and has the characteristics of simple structure, convenient manufacturing and low cost.

[0054] The planetary roller 5 above the rotation axis 1 is movably mounted on the housing 2, and the planetary roller 5 below the rotation axis 1 is fixed on the housing 2, so that a plurality of planetary rollers 5 provide a more stable radial support for the rotation axis 1. The planetary roller 5 is specifically arranged as follows: the housing 2 is provided with a mounting hole 4 perpendicular to the axial direction of the rotation axis 1, and an elastic tensioner 3 is movably connected in the mounting hole 4. The elastic tensioner 3 applies a pre-tightening force to the upper planetary roller 5, so that the upper planetary roller 5 presses against the rotation axis 1. The elastic tensioner 3 of the present invention generally includes a connecting part and an elastic part. The elastic part is made of an elastic material. The method of applying a pre-tightening force to the upper planetary roller 5 can be: (1) The mounting hole 4 is a hole with a smooth inner wall. A downward acting force is applied to the elastic tensioner 3 through a pushing structure. The elastic tensioner 3 moves downward, so that the elastic part acts on the upper planetary roller 5 and deforms, and then a pre-tightening force can be applied to the upper planetary roller 5, so that the upper planetary roller 5 firmly presses on the rotation axis 1; (2) The mounting hole 4 is designed as a threaded hole, and the connecting part of the elastic tensioner 3 is also provided with a thread. The connecting part is threadedly connected in the mounting hole 4. By screwing the connecting part, the elastic tensioner 3 moves downward, and the elastic part acts on the upper planetary roller 5 and deforms, and then a pre-tightening force can be applied to the upper planetary roller 5, so that the upper planetary roller 5 firmly presses on the rotation axis 1. Through the above structure, the rotation axis 1 can be restricted to rotate between the angles of multiple rollers, so that a plurality of planetary rollers 5 provide a more stable radial support for the rotation axis 1. Since the planetary roller 5 needs to be fixed in the housing 2, bearings 6 are provided at both the front and rear ends of the planetary roller 5 in the present invention. At the same time, bearing holes corresponding to the bearings 6 are provided in the housing 2. The bearing 6 on the lower planetary roller 5 matches the lower bearing hole, that is, the outer surface of the bearing 6 on the lower planetary roller 5 fits against the inner side of the bearing hole. There is a movable gap between the bearing 6 on the upper planetary roller 5 and the upper bearing hole. The elastic tensioner 3 applies a pre-tightening force to the bearing 6 on the upper planetary roller 5, so that the node where the elastic tensioner 3 applies a pre-tightening force to the planetary roller 5 is arranged inside the housing 2, playing a protective role, making the pre-tightening force applied by the elastic tensioner 3 to the planetary roller 5 reliable and safe. The width of the planetary roller 5 of the present invention can be freely set according to the working conditions.

[0055] The outer diameter of the planetary roller 5 (designated as N) is generally larger than the outer diameter of the rotating shaft 1 (designated as D). The ratio between the outer diameter N of the planetary roller 5 and the outer diameter D of the rotating shaft 1 determines the ratio of the rotational speed of the rotating shaft 1 to the rotational speed of the bearing 6 of the planetary roller 5. The reduction ratio calculation formula is N / D = P. When the rotational speed of the rotating shaft 1 is constant and the outer diameter of the rotating shaft 1 is constant, the larger the P value, the lower the rotational speed of the bearing 6 of the planetary roller 5. For example, if the rotational speed of the rotating shaft 1 of a high-speed motor is designed to be 120000 rpm, the outer diameter of the rotating shaft 1 is 15 mm, and the outer diameter of the planetary roller 5 is 75 mm, then the calculated P value is 5, and the rotational speed of the roller support bearing 6 is only 24000 rpm, greatly reducing the rotational speed load and processing difficulty of the roller support bearing 6, making it possible to replace the original high-grade precision bearing with an ordinary-grade bearing.

[0056] The planetary rollers 5 are circumferentially distributed on the rotating shaft 1 in the same plane. The number of planetary rollers 5 below the rotating shaft 1 is at least two, and the angle between two planetary rollers 5 below the rotating shaft 1 is greater than 0 degrees and less than 180 degrees, achieving the effects of simple structure and convenient manufacturing. The specific design of the number and distribution of the planetary rollers 5: Three planetary rollers 5 are circumferentially distributed on the rotating shaft 1 in the same plane, and the sizes of the three planetary rollers 5 are the same, and the angle between two planetary rollers 5 is 120 degrees. When the rotational speed of the rotating shaft 1 is low and the limit rotational speed of the bearing 6 of the planetary roller 5 is high, and there is a surplus of P value, generally three planetary rollers 5 on the same support surface are taken as a group. In order to pursue the maximum P value, the three planetary rollers 5 are generally arranged in a circumferential 120-degree uniform distribution. The sizes of the three planetary rollers 5 are the same. When three planetary rollers 5 of the same size are evenly distributed at 120 degrees in the same plane, the maximum P value of 6.45 can be obtained. As Figure 10 shown, T1 = T2 = 120 degrees. It is also possible to set different sizes for each planetary roller 5 according to needs, and a non-120-degree uniform circumferential angle arrangement can be set, such as Figure 11 shown, T4 > T3. When the rotational speed of the rotating shaft 1 is high and the limit rotational speed of the bearing 6 of the planetary roller 5 is low, and the P value is insufficient, different support surfaces can be selected and the diameter of the planetary roller 5 can be increased to increase the P value, that is, the planetary roller 5 is not supported on the rotating shaft 1 in one plane, and theoretically an infinite P value can be obtained, such as Figure 5 and Figure 6 shown. According to the size of the planetary roller 5, four planetary rollers 5 can be set to radially support the rotating shaft 1, such as Figure 13 shown.

[0057] An axial thrust support is formed between the planetary roller 5 and the rotating shaft 1 to limit the axial movement of the rotating shaft 1. The axial thrust support method is specifically divided into cylindrical planetary rollers (such as Figure 14 ), stepped planetary rollers (such as Figure 15 ), conical planetary rollers (such asFigure 16 ) The wedge-shaped planetary roller 5 (such as Figure 17 ) The arc-shaped planetary roller (such as Figure 18 ), specifically:

[0058] (1) Cylindrical planetary roller 5: A raised roller thrust surface 7 is provided at the edge of the planetary roller 5. The roller thrust surface 7 can be provided on both sides or only on one side. A raised rotating shaft thrust surface 8 is provided at the edge of the rotating shaft 1. The roller thrust surface 7 and the rotating shaft thrust surface 8 are in contact to provide a one-way thrust function to the rotating shaft 1.

[0059] (2) Step-shaped planetary roller 5: A stepped roller thrust surface 7 is provided at the edge of the planetary roller 5. A rotating shaft thrust surface 8 that matches the stepped roller thrust surface 7 is provided at the edge of the rotating shaft 1. The roller thrust surface 7 and the rotating shaft thrust surface 8 are in contact to provide a one-way thrust function to the rotating shaft 1.

[0060] (3) Conical planetary roller 5: The shape of the planetary roller 5 is designed as a conical shape. The outer surface of the planetary roller 5 serves as the roller conical surface. A first raised portion in the shape of a cone is provided at the edge of the rotating shaft 1. The outer surface of the first raised portion serves as the rotating shaft 1 conical surface. The taper of the roller conical surface is opposite to the taper of the rotating shaft 1 conical surface. The roller conical surface and the rotating shaft 1 conical surface cooperate with each other. There is no need for a special thrust surface between the planetary roller 5 and the rotating shaft 1 to provide a one-way thrust function to the rotating shaft 1.

[0061] (4) Wedge-shaped planetary roller 5: A wedge-shaped limit connection is provided between the planetary roller 5 and the rotating shaft 1. A wedge-shaped groove can be provided on the planetary roller 5, and a raised portion is provided on the rotating shaft 1 to form a wedge shape, so that the raised portion on the rotating shaft 1 matches the groove on the planetary roller 5; or a wedge-shaped groove is provided on the rotating shaft 1, and a raised portion is provided on the planetary roller 5 to form a wedge shape, so that the raised portion on the planetary roller 5 matches the groove on the rotating shaft 1. There is no need for a special thrust surface between the planetary roller 5 and the rotating shaft 1 to provide a two-way thrust function to the rotating shaft 1.

[0062] (5) Arc-shaped planetary roller 5: The planetary roller 5 is provided with a first arc surface, and the rotating shaft 1 is provided with a second arc surface opposite to the first arc surface. The second arc surface and the first arc surface cooperate with each other. There is no need for a special thrust surface between the planetary roller 5 and the rotating shaft 1 to provide a two-way thrust function to the rotating shaft 1.

[0063] The supporting method of the high-speed motor main shaft planetary gear supporting device includes the following steps:

[0064] a. Design the shape of the planetary roller 5, and design the shape of the rotating shaft 1 according to the shape of the planetary roller 5, so that an axial thrust support is formed between the planetary roller 5 and the rotating shaft 1 to limit the axial movement of the rotating shaft 1.

[0065] The present invention provides radial support for the rotating shaft 1 through multiple planetary rollers 5; at the same time, an axial thrust support is formed between the planetary rollers 5 and the rotating shaft 1 to limit the axial movement of the rotating shaft 1.

[0066] b. Design of the outer diameter of the planetary roller 5 and output the rotational speed of the bearing 6 of the planetary roller 5: Set the outer diameter of the planetary roller 5 as N and the outer diameter of the rotating shaft 1 as D. The ratio between the outer diameter N of the planetary roller 5 and the outer diameter D of the rotating shaft 1 determines the ratio of the rotational speed of the rotating shaft 1 to the rotational speed of the bearing 6 of the planetary roller 5. According to the reduction ratio calculation formula P = N / D, when the outer diameter D of the rotating shaft 1 is constant, adjust the value of the outer diameter N of the planetary roller 5. With the rotational speed of the rotating shaft 1 constant, output the rotational speed of the bearing 6 of the planetary roller 5.

[0067] When the rotational speed of the rotating shaft 1 is constant and the outer diameter of the rotating shaft 1 is constant, the larger the P value, the lower the rotational speed of the bearing 6 of the planetary roller 5. For example, if the rotational speed of the rotating shaft 1 of a high-speed motor is designed to be 120000 rpm, the outer diameter of the rotating shaft 1 is 15 mm, and the outer diameter of the planetary roller 5 is 75 mm, then the calculated P value is 5, and the rotational speed of the roller support bearing 6 is only 24000 rpm, greatly reducing the rotational speed load and processing difficulty of the roller support bearing 6, making it possible to replace the original high-grade precision bearing with an ordinary-grade bearing.

[0068] c. Design the distribution of the planetary rollers 5 acting on the rotating shaft 1: On the premise of ensuring a sufficient reduction ratio P value, design three planetary rollers 5 to be circumferentially distributed on the rotating shaft 1 in the same plane. The sizes of the three planetary rollers 5 are the same, and the three planetary rollers 5 are evenly distributed at 120 degrees circumferentially.

[0069] When three rollers of the same size are evenly distributed at 120 degrees in the same plane, the maximum P value that can be obtained is 6.45.

[0070] d. Design the force exerted by the planetary rollers 5 on the rotating shaft 1: One planetary roller 5 above the rotating shaft 1 is designed to be movable on the housing 2. Install the bearing 6 on the upper planetary roller 5 into the upper bearing hole, and there is a movable gap between the two. At the same time, the two planetary rollers 5 below the rotating shaft 1 are designed to be fixed on the housing 2, and the bearing 6 on the lower planetary roller 5 is limited to the lower bearing hole.

[0071] e. The planetary rollers 5 exert a force perpendicular to the axis direction of the rotating shaft 1 on the rotating shaft 1: Install an elastic tensioner 3 in the mounting hole 4 perpendicular to the axis direction of the rotating shaft 1 on the housing 2, and then apply a downward force to the elastic tensioner 3 in the mounting hole 4. The elastic tensioner 3 applies a pre-tightening force to the upper planetary roller 5, causing the upper planetary roller 5 to move vertically downward, so that the three planetary rollers 5 press on the rotating shaft 1.

[0072] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions or modifications made based on the present invention to solve substantially the same technical problems and achieve substantially the same technical effects are all covered by the protection scope of the present invention.

Claims

1. Planetary gear support device for high-speed motor spindle, comprising: a housing; a rotating shaft, which is installed in the housing; It is characterized in that: It further includes at least three planetary rollers installed on the housing. The planetary rollers are arranged circumferentially around the rotating shaft as the center, and each planetary roller applies a force perpendicular to the axial direction of the rotating shaft to the rotating shaft; The planetary rollers above the rotating shaft are movable on the housing, and the planetary rollers below the rotating shaft are fixed on the housing; The housing is provided with a mounting hole perpendicular to the axial direction of the rotating shaft. An elastic tensioner is movably connected in the mounting hole. The elastic tensioner applies a pre-tightening force to the upper planetary rollers, so that the upper planetary rollers press on the rotating shaft; The elastic tensioner is divided into a connecting part and an elastic part. The elastic part is made of an elastic material. The way to apply a pre-tightening force to the upper planetary rollers is one of the following ways: Way 1: The mounting hole is a hole with a smooth inner wall. A downward force is applied to the elastic tensioner by a pushing structure. The elastic tensioner can move downward, so that the elastic part acts on the upper planetary rollers and deforms, and can apply a pre-tightening force to the upper planetary rollers; Way 2: The mounting hole is designed as a threaded hole. The connecting part is provided with threads. The connecting part is threadedly connected in the mounting hole. By screwing the connecting part, the elastic tensioner can move downward. The elastic part acts on the upper planetary rollers and deforms, and then can apply a pre-tightening force to the upper planetary rollers; Bearings are provided at both the front and rear ends of the planetary rollers. The housing is provided with bearing holes corresponding to the bearings. The bearings on the lower planetary rollers match the lower bearing holes, and there is a movable gap between the bearings on the upper planetary rollers and the upper bearing holes. The elastic tensioner applies a pre-tightening force to the bearings on the upper planetary rollers.

2. The planetary gear support device for high-speed motor spindle according to claim 1, It is characterized in that: The outer diameter of the planetary roller is larger than the outer diameter of the rotating shaft.

3. The planetary gear support device for high-speed motor spindle according to claim 1 or 2, It is characterized in that: The planetary rollers are circumferentially distributed on the rotating shaft in the same plane. The number of the planetary rollers below the rotating shaft is at least two, and the included angle between the two planetary rollers below the rotating shaft is greater than 0 degrees and less than 180 degrees.

4. The planetary gear support device for high-speed motor spindle according to claim 3, It is characterized in that: Three planetary rollers are circumferentially distributed on the rotating shaft in the same plane. The sizes of the three planetary rollers are the same, and the included angle between two planetary rollers is 120 degrees.

5. The planetary gear support device for high-speed motor spindle according to claim 1, It is characterized in that: An axial thrust support is formed between the planetary roller and the rotating shaft, which is used to limit the axial movement of the rotating shaft.

6. The planetary gear support device for the high-speed motor spindle according to claim 5, characterized in that: The axial thrust support method is specifically divided into: (1) A raised roller thrust surface is provided at the edge of the planetary roller, and a raised rotating shaft thrust surface is provided at the edge of the rotating shaft. The roller thrust surface and the rotating shaft thrust surface are in contact to provide a one-way thrust function to the rotating shaft; (2) A stepped roller thrust surface is provided at the edge of the planetary roller, and a rotating shaft thrust surface that matches the stepped roller thrust surface is provided at the edge of the rotating shaft. The roller thrust surface and the rotating shaft thrust surface are in contact to provide a one-way thrust function to the rotating shaft; (3) The shape of the planetary roller is designed as a conical shape. The outer surface of the planetary roller is used as the roller conical surface. A first convex portion in a conical shape is provided at the edge of the rotating shaft, and the outer surface of the first convex portion is used as the rotating shaft conical surface. The taper of the roller conical surface is opposite to the taper of the rotating shaft conical surface. The roller conical surface and the rotating shaft conical surface cooperate with each other to provide a one-way thrust function to the rotating shaft; (4) A wedge-shaped limit connection is provided between the planetary roller and the rotating shaft to provide a two-way thrust function to the rotating shaft; (5) The planetary roller is provided with a first arc surface, and the rotating shaft is provided with a second arc surface opposite to the first arc surface. The second arc surface and the first arc surface cooperate with each other to provide a two-way thrust function to the rotating shaft.

7. The support method for the planetary gear support device of the high-speed motor spindle according to claim 1, characterized in that it includes the following steps: a. Design the shape of the planetary roller, and design the shape of the rotating shaft according to the shape of the planetary roller, so that an axial thrust support is formed between the planetary roller and the rotating shaft to limit the axial movement of the rotating shaft; b. Design the outer diameter of the planetary roller and output the bearing speed of the planetary roller: Set the outer diameter of the planetary roller as N and the outer diameter of the rotating shaft as D. The ratio between the outer diameter N of the planetary roller and the outer diameter D of the rotating shaft determines the ratio of the rotating shaft speed to the bearing speed of the planetary roller. According to the reduction ratio calculation formula P = N / D, when the outer diameter D of the rotating shaft is constant, adjust the value of the outer diameter N of the planetary roller, and output the bearing speed of the planetary roller through the constant rotating shaft speed; c. Design the distribution of the planetary rollers acting on the rotating shaft: On the premise of ensuring a sufficient reduction ratio P value, design three planetary rollers to be circumferentially distributed on the rotating shaft in the same plane. The sizes of the three planetary rollers are the same, and the three planetary rollers are evenly distributed at 120 degrees circumferentially; d. Design the force exerted by the planetary rollers on the rotating shaft: One planetary roller above the rotating shaft is designed to be movable on the housing. Install the bearing on the upper planetary roller into the upper bearing hole, and there is a movable gap between the two. At the same time, the two planetary rollers below the rotating shaft are designed to be fixed on the housing, and the bearings on the lower planetary rollers are limited to the lower bearing holes; e. The planetary rollers apply a force perpendicular to the axis of rotation of the rotating shaft in the axial direction: An elastic tensioner is installed in the mounting hole of the housing in the axial direction perpendicular to the axis of rotation of the rotating shaft, and then a downward force is applied to the elastic tensioner in the mounting hole. The elastic tensioner applies a pre-tightening force to the upper planetary rollers, causing the upper planetary rollers to move vertically downward, so that the three planetary rollers press on the rotating shaft.

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