Roller screw

Abstract

The utility model provides a roller lead screw. The roller lead screw comprises a roller body, a lead screw body and a nut body. The middle of the roller body is a threaded section, and the two sides of the threaded section are planetary tooth sections. The outer side face of the lead screw body is meshed with the threaded section, the threaded section is meshed with the inner wall of the nut body, fixing end covers are assembled at the two axial ends of the roller body, the fixing end covers are assembled on the lead screw body, a sun tooth part is arranged on the outer side face of the lead screw body, and the planetary tooth section is connected with the sun tooth part in a meshed mode. Compared with the prior art, the roller lead screw has the following beneficial effects that compared with a traditional roller lead screw structure, the structure is more compact, the occupied space is reduced, and the requirements of specific application scenes such as high-precision positioning and short stroke can be better met.

Description

Technical Field

[0001] The utility model belongs to the technical field of roller screws, and in particular relates to a roller screw. Background Art

[0002] A roller screw is a precision transmission device that converts rotational motion into linear motion and is widely used in various high-precision positioning and drive systems. Traditional roller screws typically consist of a screw body, a nut, and multiple rollers. The rollers roll between the screw and nut, achieving low-friction, high-efficiency transmission through the rolling motion of the rollers.

[0003] In traditional roller screws, the nut is attached to the screw body, which is generally suitable for longer travel applications. However, in some applications with shorter travel and limited space, this structure cannot meet the requirements of compact design. Furthermore, the traditional roller screw has a complex internal structure, resulting in high manufacturing costs. The outer diameter of the nut is larger than that of the screw body, which can lead to inconvenience in installation and maintenance.

[0004] In summary, existing roller screw structures have certain limitations in terms of compactness, structural complexity, and applicable travel range. These shortcomings are particularly evident in applications requiring high-precision positioning and short travel. Therefore, developing a more compact, structurally simple roller screw structure suitable for short-travel, high-precision positioning is of great practical significance. Utility Model Content

[0005] In order to solve the above technical problems, the present invention solves them through the following technical solutions.

[0006] A roller screw comprises a roller body, a screw body, and a nut body. The roller body has a threaded section in the middle, flanked by planetary gear segments. The outer side of the screw body meshes with the threaded section, which in turn meshes with the inner wall of the nut body. Fixed end caps are mounted on the screw body at both axial ends of the roller body. A sun gear portion is provided on the outer side of the screw body, and the planetary gear segments mesh with the sun gear portion. Compared to traditional roller screw structures, this structure is more compact, occupies less space, and can better meet the needs of specific applications such as high-precision positioning with a short travel distance.

[0007] As a preferred technical solution for a roller screw, the screw body comprises a connecting portion and a length portion. The connecting portion is provided with a threaded portion for engaging with the threaded segment, and the sun teeth are arranged on either axial side of the threaded portion. The connecting portion is provided with a fixing groove for mounting a fixed end cap. The fixed end cap near the end face of the connecting portion is fixed to the connecting portion via a shaft retaining spring. This design ensures a reliable connection between the roller and the screw body. In addition, the fixing groove near the length portion has been structurally optimized by increasing the diameter of the shaft end, eliminating the need for a shaft retaining spring and saving component costs.

[0008] As a preferred technical solution for a roller screw, a clearance groove is provided between the threaded portion and the sun tooth portion. The clearance groove design can reduce machining requirements at the connection between the threaded portion and the sun tooth portion, reduce noise when the screw and nut mesh, and extend service life.

[0009] As a preferred technical solution for a roller screw, the screw body is hollow inside and closed at the end with the connecting portion. The hollow design reduces the weight of the screw body and reduces material costs.

[0010] As a preferred technical solution for a roller screw, the sun tooth features a helical involute profile and meshes with the inner wall of the nut. This design serves the dual function of a gear and a thread, effectively meshing with the planetary gear segments while also forming a good meshing relationship with the inner wall of the nut. This design not only improves transmission efficiency but also enhances overall stability and durability.

[0011] Compared with the prior art, the present application has the following beneficial effects: the roller screw structure is improved, the structure is more compact, and is suitable for application scenarios with high-precision positioning but short stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A three-dimensional schematic diagram of a roller screw.

[0013] Figure 2 This is a cross-sectional view of the local structure of the roller screw.

[0014] Figure 3 This is an exploded diagram of the roller screw structure.

[0015] Figure 4 Schematic diagram of the structure of the connection part.

[0016] Figure 5 Schematic diagram of the structure of the roller body.

[0017] The following is a description of the symbols in the drawings of the specification:

[0018] 10. Roller; 11. Threaded segment; 12. Planetary gear segment; 13. Fixed end cover; 14. Shaft retaining spring;

[0019] 20. Screw body; 21. Connecting portion; 22. Length portion; 23. Threaded portion; 24. Sun tooth portion; 25. Fixing groove; 26. Clearance groove;

[0020] 30. Nut body. DETAILED DESCRIPTION

[0021] The present invention will be described in further detail below with reference to the accompanying drawings and specific implementations.

[0022] In the following embodiments, the same or similar numbers throughout represent the same or similar components or components 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 understood as limiting the present invention.

[0023] In the description of the present invention, 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 directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and therefore cannot be understood as limiting the present invention. 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 invention, 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 meaning of the above terms in this utility model according to the specific circumstances.

[0024] Reference Figures 1 to 5 A roller screw comprises a roller body 10, a screw body 20 and a nut body 30. The roller body 10 has a threaded section 11 in the middle, and planetary gear sections 12 on both sides of the threaded section 11. The outer side surface of the screw body 20 meshes with the threaded section 11, and the threaded section 11 meshes with the inner wall of the nut body 30. The roller body 10 is equipped with fixed end covers 13 at both axial ends, and the fixed end covers 13 are assembled on the screw body 20. A sun tooth portion 24 is provided on the outer side surface of the screw body 20, and the planetary gear segments 12 and the sun tooth portion 24 are meshed and connected. Compared with the traditional roller screw structure, this structure is more compact, reduces the occupied space, and can better meet the needs of specific application scenarios such as high-precision positioning but short stroke.

[0025] The screw body 20 includes a connecting portion 21 and a length portion 22. The connecting portion 21 is provided with a threaded portion 23 for engaging with the threaded segment 11, and the sun teeth 24 are arranged on both axial sides of the threaded portion 23. The connecting portion 21 is provided with a fixing groove 25 for mounting a fixed end cap 13. The fixed end cap 13 near the end surface of the connecting portion 21 is fixed to the connecting portion 21 via a shaft retaining spring 14. This design ensures the reliability of the connection between the roller and the screw body 20. In addition, the fixing groove 25 near the length portion 22 has been structurally optimized by increasing the diameter of the shaft end, eliminating the need for a shaft retaining spring 14 and saving component costs.

[0026] Specifically, a clearance groove 26 is provided between the threaded portion 23 and the sun tooth portion 24. This design reduces machining requirements at the connection between the threaded portion 23 and the sun tooth portion 24, reduces noise during meshing between the lead screw and the nut, and prolongs the lead screw's service life. Furthermore, the clearance groove 26 serves as an oil reservoir, allowing lubricating oil to be more easily distributed to the contact surface between the threaded portion 23 and the sun tooth portion 24, thereby reducing wear and maintaining long-term stable operation of the lead screw.

[0027] The screw body 20 is hollow inside and closed at the end with the connecting portion 21. The hollow design reduces the weight of the screw body 20 and reduces material costs. The sun tooth portion 24 has a helical involute tooth profile and is meshed with the inner wall of the nut body 30. In this way, the sun tooth portion 24 simultaneously performs the dual functions of a gear and a thread, effectively meshing with the planetary gear segment and forming a good meshing relationship with the inner wall of the nut. This design not only improves transmission efficiency, but also enhances overall stability and durability.

[0028] The protection scope of the present invention includes but is not limited to the above embodiments. The protection scope of the present invention is based on the claims. Any replacement, deformation, and improvement of the technology that can be easily thought of by technicians in this field fall within the protection scope of the present invention.

Claims

1. A roller screw, comprising a roller body (10), a screw body (20) and a nut body (30); the roller body (10) has a threaded section (11) in the middle, and planetary gear sections (12) are provided on both sides of the threaded section (11); the outer side surface of the screw body (20) is meshed with the threaded section (11), and the threaded section (11) is meshed with the inner wall of the nut body (30), characterized in that: The roller body (10) is equipped with fixed end covers (13) at both axial ends. The fixed end covers (13) are assembled on the screw body (20). A sun gear portion (24) is provided on the outer surface of the screw body (20). The planetary gear segment (12) and the sun gear portion (24) are meshed and connected.

2. A roller screw according to claim 1, characterized in that: The screw body (20) comprises a connecting portion (21) and a length portion (22); the connecting portion (21) is provided with a threaded portion (23) for engaging with the threaded segment (11); the sun tooth portions (24) are provided on both axial sides of the threaded portion (23); the connecting portion (21) is provided with a fixing groove (25) for installing a fixed end cover (13); the fixed end cover (13) near the end face of the connecting portion (21) is fixedly assembled with the connecting portion (21) through a shaft retaining ring (14).

3. The roller screw according to claim 2, characterized in that: A clearance groove (26) is provided between the threaded portion (23) and the sun gear portion (24).

4. The roller screw according to claim 2, characterized in that: The screw body (20) is hollow inside, and the screw body (20) is closed at an end having a connecting portion (21).

5. The roller screw according to claim 1, characterized in that: The sun tooth portion (24) is a helical involute tooth shape, and the sun tooth portion (24) is meshedly connected to the inner wall of the nut body (30).

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