Planetary roller transmission structure

Abstract

A planetary roller transmission structure comprises a planetary roller set composed of a plurality of planetary rollers distributed in the circumferential direction, a first meshing section is arranged on each planetary roller, a plurality of first protruding rings are arranged on each first meshing section, and the inclination angle of each first protruding ring in the radial direction is 0 degree; the first protruding rings on every two adjacent planetary pin rollers are arranged in a staggered mode, so that the planetary pin roller sets can be integrally meshed with the external thread structure. The meshing structure is one of the innovative structures in the application, the first protruding ring with the inclination angle of 0 degree is adopted on the planetary roller for meshing with the external thread, and compared with traditional thread meshing, the structural strength of the planetary roller in the meshing structure is higher; the formed planetary roller group is more stable in structure and larger in reverse self-locking force while stably bearing axial thread thrust.

Description

Technical Field

[0001] The utility model belongs to the technical field of transmission structures, and in particular relates to a planetary roller transmission structure. Background Art

[0002] Screw drive is a very common transmission structure in the industrial field, with high transmission accuracy and simple structure. The traditional screw drive structure includes a threaded screw and a matching internal thread sleeve, and basically the screw rotates, and the thread matches to drive the axial movement of the internal thread sleeve. This structure is widely used in the industry.

[0003] In the prior art, planetary roller transmission structures are also used in screw transmission devices. Conventional planetary rollers are provided with threads and gear structures, which have many wear structures and the gears cannot withstand axial forces. All axial forces are applied to the threads, which shortens the life of the planetary rollers and reduces the transmission accuracy.

[0004] Therefore, based on the above situation, the present application further designs and improves the planetary roller transmission structure. Utility Model Content

[0005] In view of the above deficiencies in the prior art, the utility model provides a planetary roller transmission structure, which performs transmission through specially designed planetary rollers, has high transmission efficiency, high precision, long service life, and strong self-locking force, and is particularly suitable for telescopic arm application scenarios with high precision requirements.

[0006] The utility model solves the problem through the following technical solutions.

[0007] A planetary roller transmission structure comprises a planetary roller group consisting of a plurality of circumferentially distributed planetary rollers, wherein the planetary roller is provided with a first meshing section, and the first meshing section is provided with a plurality of first protruding rings, wherein the inclination angle of the first protruding rings in the radial direction is 0°; the first protruding rings on two adjacent planetary rollers are staggered so that the planetary roller group can be meshed as a whole on an external threaded structure.

[0008] This structure is one of the innovative structures in the present application. The planetary roller adopts a first protruding ring with an inclination angle of 0° to engage with the external thread. Compared with the traditional thread engagement, the planetary roller in the engagement structure in the present application has higher structural strength. The planetary roller group formed can stably withstand the axial thread thrust while having a more stable structure and a greater reverse self-locking force.

[0009] In a preferred embodiment, second meshing sections are provided at both ends of the planetary roller, the maximum diameter of the second meshing section is smaller than the maximum diameter of the first meshing section, and a plurality of second protruding rings are provided on the second meshing section, and the axial inclination angle of the second protruding rings is 0°.

[0010] In a preferred embodiment, the ratio of the axial length a of the second meshing section to the axial length b of the first meshing section is 1:2.5~1:2.7, preferably 1:2.6. The planetary roller under this structure has a first meshing section in the middle section and second meshing sections at both ends. While ensuring transmission efficiency, the overall strength is high and the self-locking force is strong.

[0011] In a preferred embodiment, it also includes a screw rod, which is provided with a transmission end, and third meshing sections are provided on both sides of the transmission end, and the third meshing section is provided with a plurality of third protruding rings that cooperate with the second protruding ring, and the axial inclination angle of the third protruding ring is 0°. This structure is also one of the innovative structures in this application. The axial force applied to the planetary roller set by the outside will be applied to the third meshing section on the screw rod through the second meshing section on each planetary roller, pushing the axial movement of the screw rod without getting stuck. At the same time, the force structure between the second protruding ring and the third protruding ring with an inclination angle of 0° is stable, and the screw rod can perform axial telescopic movement without self-rotation, with high precision, good stability and high strength.

[0012] In a preferred embodiment, a position on the transmission end corresponding to the first meshing section is a recessed section, and the recessed section is used to avoid interference with the first meshing section.

[0013] In a preferred embodiment, the planetary roller group also includes assembly rings at both ends, the assembly rings are provided with assembly holes, and both ends of the planetary rollers are provided with assembly cams. The planetary rollers are rotatably assembled into the assembly holes through the assembly cams, thereby forming a stable planetary roller group with high overall strength, good coordination, and high transmission accuracy during operation.

[0014] In a preferred embodiment, a snap ring is provided on the outer side of the assembly ring to limit the assembly ring and prevent it from falling out.

[0015] In a preferred embodiment, the planetary roller set is composed of 5 to 7 planetary rollers evenly distributed circumferentially, preferably six, which are evenly distributed, have structural stability, high transmission efficiency and high precision.

[0016] In a preferred embodiment, the planetary rollers are plastic rollers, such as rollers made of polytetrafluoroethylene, which have good self-lubricating function, low noise and good silencing effect during operation.

[0017] Compared with the prior art, the utility model has the following beneficial effects: it provides a planetary roller transmission structure, which transmits power through specially designed planetary rollers, has high transmission efficiency, high precision, long service life, and strong self-locking force, and is particularly suitable for telescopic arm application scenarios with high precision requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional diagram of the planetary roller screw in the utility model.

[0019] Figure 2 It is a cross-sectional view of the planetary roller screw in the utility model.

[0020] Figure 3 for Figure 2 Magnified view of area A.

[0021] Figure 4 for Figure 3 Magnified view of the A1 region.

[0022] Figure 5 It is a three-dimensional diagram of the transmission structure where the internal thread sleeve is omitted.

[0023] Figure 6 It is a three-dimensional diagram of the transmission structure in which the internal threaded sleeve and part of the planetary rollers are omitted.

[0024] Figure 7 It is a three-dimensional diagram of a planetary roller set with some planetary rollers omitted.

[0025] Figure 8 It is a schematic diagram of the structure of the transmission end on the screw rod.

[0026] Fig. 9 It is a schematic diagram of three adjacent planetary rollers in this application. DETAILED DESCRIPTION

[0027] The utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0028] In the following embodiments, the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0029] In the description of the present utility model, it should be understood that the terms: center, longitudinal, transverse, length, width, thickness, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, etc. indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present utility model and simplifying the description, and therefore cannot be understood as limiting the present utility model. In addition, the terms: first, second, etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features shown. In the description of the present utility model, unless otherwise clearly specified and limited, the terms: install, connect, connect, etc. should be understood in a broad sense, and ordinary technicians in this field can understand the specific meanings of the above terms in this application according to the specific circumstances.

[0030] See also Figures 1 to 9 The present application relates to a reverse planetary roller screw, which includes an innovative planetary roller transmission structure.

[0031] Specifically, the reverse planetary roller screw in the present application includes: an internal threaded sleeve 1, which is a hollow cylindrical structure, and an internal thread 11 is provided on the inner wall of the hollow hole; a screw 2, one end of the screw 2 is a transmission end, and the transmission end is placed in the inner hole, and a plurality of circumferentially distributed planetary rollers 3 for transmission are provided between the transmission end and the internal thread 11, and a planetary roller group is formed; when the internal threaded sleeve 1 rotates, the axial movement of the screw 2 is realized through the transmission between the internal thread 11, the planetary rollers 3 and the transmission end.

[0032] Specifically, from the attached Fig. 9 It can be seen that the planetary roller 3 in the present application is provided with a first meshing section 31, and the first meshing section 31 is provided with a plurality of first protruding rings 311 for meshing on the internal thread 11, and the first protruding rings 311 have a radial inclination angle of 0°; and the first protruding rings 311 on two adjacent planetary rollers 3 are staggered, so that the planetary roller set can be meshed on the internal thread 11 as a whole. This structure is one of the innovative structures in the present application. The planetary roller 3 uses a first protruding ring 311 with an inclination angle of 0° for meshing. Compared with the traditional thread meshing, the planetary roller 3 in the meshing structure in the present application has a higher structural strength. The planetary roller set formed has a more stable structure while stably bearing the axial thread thrust. The 0° protruding ring can effectively prevent tilting, and the reverse self-locking force is greater, that is, in the process of actively pushing the screw, the internal thread sleeve 1 will not rotate and cannot be pushed.

[0033] From the attached Figures 6-8It can be seen that in the present application, the position on the transmission end corresponding to the first meshing section 31 is a recessed section 21, and the recessed section 21 is used to avoid interference with the first meshing section 31. The two ends of the planetary roller 3 are provided with assembly cams 35, and the two sides of the transmission end are provided with assembly rings 5, and the assembly rings 5 ​​are provided with assembly holes 51. The planetary roller 3 is rotated and assembled into the assembly holes 51 through the assembly cams 35, so as to form a stable planetary roller set with high overall strength, good coordination, and high transmission accuracy during operation. Furthermore, the outer side of the assembly ring 5 is provided with a snap ring 4, which is arranged in the clamping groove 24, and is used to limit the assembly ring 5 to prevent it from coming out.

[0034] Furthermore, second meshing sections 32 are provided at both ends of the planetary roller 3, and the maximum diameter of the second meshing section 32 is smaller than the maximum diameter of the first meshing section 31, so that the second meshing section 32 does not contact the internal thread 11; a plurality of second protruding rings 321 are provided on the second meshing section 32; third meshing sections 22 are provided on both sides of the transmission end, and a plurality of third protruding rings 221 cooperating with the second protruding ring 321 are provided in the third meshing section 22; the axial inclination angle between the second protruding ring 321 and the third protruding ring 221 is 0°. This structure is also one of the innovative structures in the present application. The axial force applied by the internal threaded sleeve 1 to the planetary roller set will be applied to the third meshing segment 22 on the screw rod 2 through the second meshing segment 32 on each planetary roller 3, thereby promoting the axial movement of the screw rod 2 without getting stuck. At the same time, the force-bearing structure between the second protruding ring 321 and the third protruding ring 221 with an inclination angle of 0° is stable, and the screw rod 2 can perform axial telescopic movement without self-rotation, with high precision, good stability and high strength.

[0035] From the attached Fig. 9 It can be seen that in the specific structure, the ratio of the axial length a of the second meshing segment 32 to the axial length b of the first meshing segment 31 is 1:2.5~1:2.7, preferably 1:2.6. The planetary roller 3 under this structure has a first meshing segment 31 in the middle section and second meshing segments 32 at both ends. While ensuring the transmission efficiency, the overall strength is high, which can meet sufficient load-bearing capacity and rigidity, and has strong self-locking force.

[0036] In addition, in the present application, there is a gap 55 between the inner surface of the assembly ring 5 and the table 23 on the transmission end, that is, the entire planetary roller group has basically no contact points at other positions except the meshing position of the convex ring, so that the planetary roller group is in a semi-floating state to avoid getting stuck. At the same time, the friction resistance is small, the unnecessary wear on the parts is less, and the service life is long.

[0037] In the present application, the planetary roller set is composed of 5 to 7 planetary rollers 3 evenly distributed in the circumferential direction, preferably six, evenly distributed, structurally stable, with high transmission efficiency and high precision. In addition, the planetary rollers 3 can be plastic rollers, such as rollers made of polytetrafluoroethylene, which have good self-lubricating function, low noise during operation, and good mute effect.

[0038] As shown in the accompanying drawings, in a specific embodiment of the present application, the planetary roller group is composed of six planetary rollers 3 evenly distributed in the circumferential direction, which are roller No. 1, roller No. 2, roller No. 3, roller No. 4, roller No. 5, and roller No. 6 in circumferential order; on the basis of the overall matching of the helicity of the internal thread 11 by the planetary roller group: the No. 4 roller has the same structure as the No. 1 roller and is only installed in reverse during installation; the No. 5 roller has the same structure as the No. 2 roller and is only installed in reverse during installation; the No. 6 roller has the same structure as the No. 3 roller and is only installed in reverse during installation. In this structure, in order to match the internal thread 11, the first radial convex rings between adjacent planetary rollers 3 are staggered, and three planetary rollers 3 are just staggered at the position of one first radial convex ring, and the other three planetary rollers 3 are staggered at the position of another first radial convex ring. Therefore, the structure of the last three planetary rollers 3 can be the same as the structure of the first three planetary rollers 3, and they only need to be turned 180° and installed in the opposite direction during installation. Therefore, in the production process, only three specifications of planetary rollers need to be produced, which greatly saves enterprise costs and improves competitiveness.

[0039] It can be seen from the above description that in this application, a reverse-driven planetary roller screw is innovatively designed, and the screw 2 therein can be driven to move axially by rotating the internal thread sleeve 1. In addition, planetary rollers are used in the transmission structure, which has structural stability, high transmission accuracy, and strong self-locking force. As long as the internal thread sleeve 1 does not rotate, the position of the screw 2 is also fixed, and the strength is high, which is suitable for high-precision and high-strength use scenarios.

[0040] As described above, the planetary roller transmission structure in the present application performs transmission through specially designed planetary rollers, and has high transmission efficiency, high precision, long service life, and strong self-locking force, and is particularly suitable for telescopic arm application scenarios with high precision requirements.

[0041] The protection scope of the present invention includes but is not limited to the above embodiments. The protection scope of the present invention shall be based on the claims. Any replacement, deformation, and improvement of the technology that can be easily thought of by technicians in this field shall fall within the protection scope of the present invention.

Claims

1. A planetary roller transmission structure, characterized in that: Comprising a planetary roller set consisting of a plurality of circumferentially distributed planetary rollers (3), wherein the planetary roller (3) is provided with a first meshing section (31), wherein the first meshing section (31) is provided with a plurality of first protruding rings (311), and the first protruding rings (311) have an inclination angle of 0° in the radial direction; The first protruding rings (311) on two adjacent planetary rollers (3) are arranged in a staggered manner, so that the planetary roller set can be integrally engaged with the external thread structure.

2. A planetary roller transmission structure according to claim 1, characterized in that: The two ends of the planetary roller (3) are provided with second meshing sections (32), the maximum diameter of the second meshing section (32) is smaller than the maximum diameter of the first meshing section (31), the second meshing section (32) is provided with a plurality of second protruding rings (321), and the axial inclination angle of the second protruding rings (321) is 0°.

3. A planetary roller transmission structure according to claim 2, characterized in that: The ratio of the axial length a of the second meshing section (32) to the axial length b of the first meshing section (31) is 1:2.5 to 1:2.

7.

4. A planetary roller transmission structure according to claim 2, characterized in that: It also comprises a screw rod (2), the screw rod (2) being provided with a transmission end, third meshing sections (22) being provided on both sides of the transmission end, a plurality of third protruding rings (221) being provided in the third meshing section (22) for cooperating with the second protruding ring (321), and the axial inclination angle of the third protruding ring (221) being 0°.

5. A planetary roller transmission structure according to claim 4, characterized in that: A recessed section (21) is located at a position on the transmission end corresponding to the first meshing section (31), and the recessed section (21) is used to avoid interference with the first meshing section (31).

6. A planetary roller transmission structure according to claim 1, characterized in that: The planetary roller set also includes assembly rings (5) at both ends, the assembly rings (5) being provided with assembly holes (51), and assembly cams (35) being provided at both ends of the planetary rollers (3), and the planetary rollers (3) are rotatably assembled into the assembly holes (51) via the assembly cams (35).

7. A planetary roller transmission structure according to claim 6, characterized in that: A snap ring (4) is provided on the outer side of the assembly ring (5).

8. A planetary roller transmission structure according to any one of claims 1 to 7, characterized in that: The planetary roller set is composed of 5 to 7 planetary rollers (3) evenly distributed in the circumferential direction.

9. A planetary roller transmission structure according to claim 8, characterized in that: The planetary rollers (3) are plastic rollers.

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