Method for assembling reverse planetary roller screw pair

Abstract

The invention relates to the technical field of planetary roller screw assembly methods, in particular to an assembly method of a reverse planetary roller screw pair. In order to solve the technical problem that the assembling mode of an existing planetary roller lead screw pair has defects, the radial retainers and the circumferential retainers are used, and the assembling process is simplified as follows: a lead screw and a roller are rapidly assembled into an integrated module, and then the integrated module and a nut are rapidly assembled. By means of the mode, the lead screw and the pin roller can be efficiently and conveniently assembled, the transmission precision and performance of the reverse type planetary pin roller lead screw pair are guaranteed, and meanwhile the overall assembling efficiency of the reverse type planetary pin roller lead screw pair is improved. And the radial retainers and the circumferential retainers are simple in structure, simple in assembly process and easy to match with intelligent equipment such as mechanical arms, so that industrialized automatic assembly can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of planetary roller screw assembly methods, and in particular to an assembly method of a reverse planetary roller screw pair. Background Art

[0002] The planetary roller screw pair is a rolling screw transmission mechanism that converts linear and rotary motions into each other. Its basic principle is to transmit power through multi-point threaded contact between multiple rollers and the screw and nut raceway. In recent years, with the rapid development of humanoid robots, planetary roller screw pairs have begun to be used in robot joints. Among them, the reverse planetary roller screw pair, as a commonly used planetary roller screw pair in the field of humanoid robots, has the advantages of large load-bearing capacity, high precision, high efficiency, no pollution, and easy maintenance. In the reverse planetary roller screw pair, the two ends of the threaded section on the roller are compounded with gears to form the end tooth section of the roller, and the two ends of the threaded section on the screw are also provided with gears to form the end tooth section of the screw. The gear meshing formed between the end tooth sections of the screw and the roller can limit the roller and prevent the roller from skewing.

[0003] However, the problem of automated assembly of reverse planetary roller screw pairs on industrial sites is one of the reasons that hinder the further mass production of reverse planetary roller screw pairs. The existing assembly methods and operations cannot ensure the transmission accuracy and performance of the planetary roller screw pairs while having high assembly efficiency, and the equipment and labor costs are high. Summary of the invention

[0004] In response to the technical problem that the existing assembly method of the planetary roller screw pair has defects, the present invention provides an assembly method of an inverse planetary roller screw pair, which can efficiently and conveniently realize the assembly of the screw and the roller by using radial retainers and circumferential retainers, while ensuring the transmission accuracy and performance of the inverse planetary roller screw pair, and improving the overall assembly efficiency of the inverse planetary roller screw pair.

[0005] The technical solution provided by the present invention is: an assembly method of a reverse planetary roller screw pair, comprising: S1, preparing a radial retainer and a circumferential retainer: the radial retainer is cylindrical, and a through notch is arranged on the radial retainer; the circumferential retainer comprises a barrel, an end block is fixedly arranged on one side of the barrel, and open limiting grooves are evenly arranged on the end block along the circumference, and the number of the limiting grooves is consistent with the number of rollers; S2, arranging the two circumferential retainers on both sides of one radial retainer respectively: ensuring that the end block on any circumferential retainer is adjacent to the radial retainer; at the same time, ensuring that the center plane P1 of the limiting groove corresponding to the notch on any circumferential retainer coincides with the center plane P2 of the notch; S3, installing the screw into the radial retainer and the circumferential retainer, ensuring that the screw, the radial retainer and the circumferential retainer are coaxially matched, and ensuring that the center plane P2 and the screw The plane P3 where the thread starting point R1 is located coincides with each other, and the screw is clamped to ensure that the screw is fixed; S4, push a roller into the gap until the optical axis section of the roller is stuck in the limit groove, and ensure that the end tooth section of the roller and the end tooth section of the screw, as well as the thread section of the roller and the thread section of the screw are matched at the same time; S5, the two circumferential retainers rotate synchronously at a fixed angle, and drive the rollers to rotate at the same time, leaving the gap, ensuring that the center plane P1 of the next limit groove corresponding to the gap coincides with the center plane P2 of the gap; S6, repeat S4 and S5 until all rollers are assembled; S7, remove the circumferential retainer on one side, and install the retainer and elastic retainer on this side in turn, then remove the circumferential retainer on the other side, and install the retainer and elastic retainer on this side in turn, so that the screw, roller, retainer and elastic retainer constitute an integrated module; S8, screw the integrated module into the nut, and the assembly of the reverse planetary roller screw pair is completed.

[0006] Optionally, for step S4, during the process of pushing the roller into the notch, ensure that the starting point R1 of the screw thread and the starting point R2 of the roller thread are in the same plane, so that the end tooth segment of the roller and the end tooth segment of the screw, and the thread segment of the roller and the thread segment of the screw can cooperate simultaneously.

[0007] Optionally, for step S5, a single rotation angle of the two circumferential retainers is θ=360° / N, wherein N is the number of rollers.

[0008] Optionally, for step S7, when installing the retaining frame, it is necessary to ensure that the retaining frame is coaxial with the lead screw, and each retaining hole on the retaining frame is coaxial with the corresponding roller.

[0009] Optionally, an elastic card is provided at the opening of the limiting groove, and the distance between two elastic clips located in the same limiting groove is smaller than the diameter of the optical axis section of the roller.

[0010] Optionally, a mounting groove is provided on the limiting groove, and the elastic card is fixedly disposed in the mounting groove.

[0011] Optionally, the outer diameter of the end block is smaller than the inner diameter of the radial retainer.

[0012] Optionally, the distance between the radial retainer and the lead screw is greater than the outer diameter of the roller.

[0013] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: In view of the technical problem that the existing assembly method of the planetary roller screw pair has defects, the present invention simplifies the assembly process by using radial retainers and circumferential retainers: quickly assemble the screw and the roller into an integrated module, and then quickly assemble the integrated module with the nut. This form can efficiently and conveniently realize the assembly of the screw and the roller, while ensuring the transmission accuracy and performance of the reverse planetary roller screw pair, and improving the overall assembly efficiency of the reverse planetary roller screw pair. In addition, the radial retainer and the circumferential retainer have a simple structure, a simple assembly process, and are easy to match with intelligent equipment such as a robotic arm, thereby realizing industrial automated assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is one of the schematic layout diagrams of the radial retainer and the circumferential retainer proposed in the embodiment of the present invention.

[0015] Figure 2 This is the second schematic diagram of the layout of the radial retainer and the circumferential retainer proposed in the embodiment of the present invention.

[0016] Figure 3 This is one of the schematic diagrams of the assembly method of the reverse planetary roller screw pair proposed in an embodiment of the present invention.

[0017] Figure 4 This is a second schematic diagram of the assembly method of the reverse planetary roller screw pair proposed in an embodiment of the present invention.

[0018] Figure 5 This is one of the assembly position relationship diagrams of the lead screw and the roller proposed in the embodiment of the present invention.

[0019] Figure 6 This is the second diagram of the relationship between the assembly positions of the lead screw and the roller according to the embodiment of the present invention.

[0020] Figure 7 It is a schematic diagram of the structure explosion of the reverse planetary roller screw pair proposed in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments.

[0022] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the invention. It should also be noted that, for the convenience of description, only the parts related to the invention are shown in the accompanying drawings. The words "first", "second", etc. described in the present invention are set for the convenience of describing the technical solution of the present invention, and have no specific limiting effect. They are all general references and do not constitute a limiting effect on the technical solution of the present invention. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be a connection between the insides of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Multiple technical solutions in the same embodiment, and multiple technical solutions in different embodiments, can be arranged and combined to form new technical solutions without contradictions or conflicts, all of which are within the scope of protection required by the present invention.

[0023] Combined with Figure 1 To Attachment Figure 7 This embodiment provides an assembly method for a reverse planetary roller screw pair, comprising: S1, combining with the attached Figure 1 and attached Figure 2 As shown, a radial retainer 1 and a circumferential retainer 2 are prepared: the radial retainer 1 is cylindrical, and a through notch 10 is arranged on the radial retainer 1; the circumferential retainer 2 includes a barrel 20, and an end block 21 is fixedly arranged on one side of the barrel 20, and open limiting grooves 22 are evenly arranged on the end block 21 along the circumferential direction, and the number of the limiting grooves 22 is consistent with the number of rollers 30.

[0024] In this embodiment, the function of the circumferential retainer 2 is to drive the roller 30 to perform circumferential motion around the screw 31; the function of the radial retainer 1 is to ensure that the roller 30 avoids disengagement from the screw 31 when performing circumferential motion around the screw 31.

[0025] The sizes of the radial retainer 1 and the circumferential retainer 2 mentioned in this embodiment can be replaced with corresponding sizes according to the different shaft diameters of the screw 31, and the shapes of the radial retainer 1 and the circumferential retainer 2 can be adjusted according to the actual assembly production line clamping device.

[0026] S2, combined with Figure 1 and attached Figure 2 As shown, two circumferential retainers 2 are arranged on both sides of a radial retainer 1 respectively: ensure that the end block 21 on any circumferential retainer 2 is adjacent to the radial retainer 1; at the same time, ensure that the center plane P1 of the limiting groove 22 corresponding to the notch 10 on any circumferential retainer 2 coincides with the center plane P2 of the notch 10.

[0027] S3, combined with Figure 3 and attached Figure 4 , install the lead screw 31 into the radial retainer 1 and the circumferential retainer 2 through a mechanical arm or other clamping device, ensure that the lead screw 31, the radial retainer 1 and the circumferential retainer 2 are coaxially matched, ensure that the end tooth segments on both sides of the lead screw 31 are flush with the end surface of the upper end block 21 of the circumferential retainer 2, and ensure that the center plane P2 coincides with the plane P3 where the thread starting point R1 of the lead screw 31 is located. After ensuring the above conditions, clamp the lead screw 31 to ensure that the lead screw 31 is fixed.

[0028] S4. Push a roller 30 into the notch 10 until the optical axis section of the roller 30 is stuck in the limiting groove 22, and ensure that the end tooth section of the roller 30 and the end tooth section of the screw 31, as well as the thread section of the roller 30 and the thread section of the screw 31 are matched at the same time.

[0029] In order to ensure that the end tooth segment of the roller 30 and the end tooth segment of the screw 31, as well as the thread segment of the roller 30 and the thread segment of the screw 31 are matched at the same time during assembly, it is necessary to ensure that the thread starting point R1 of the screw 31 and the thread starting point R2 of the roller 30 are in the same plane during the process of pushing the roller 30 into the notch 10. The assembly position relationship between the screw 31 and the roller 30 can be referred to in the attached Figure 5 and attached Figure 6 As shown in the figure.

[0030] In a further embodiment, an elastic card 4 is provided at the opening of the limiting groove 22, and the distance between the two elastic clips in the same limiting groove 22 is smaller than the diameter of the optical axis section of the roller 30. In this embodiment, when the roller 30 is pushed into the notch 10 of the radial retainer 1 by the automated clamping device, the optical axis section of the roller 30 will compress the elastic card 4, and after the roller 30 enters the limiting groove 22, the elastic card 4 gradually expands and resets, and when the optical axis section of the roller 30 is completely installed in the limiting groove 22, the elastic card 4 returns to its original state, thereby clamping the roller 30.

[0031] For the assembly of the elastic card 4 , a mounting groove 5 may be provided on the limiting groove 22 , and the elastic card 4 may be fixedly disposed in the mounting groove 5 , thereby achieving the assembly of the elastic card 4 and the circumferential retainer 2 .

[0032] Furthermore, in order to facilitate the insertion of the roller 30 into the limit groove 22, the outer diameter of the end block 21 is smaller than the inner diameter of the radial retainer 1, so that the size of the limit groove 22 will not be too large, and the travel of the optical axis section of the roller 30 in the limit groove 22 is smaller, which also makes it easier for the limit groove 22 and the roller 30 to disengage from each other in subsequent steps.

[0033] S5, the two circumferential retainers 2 rotate synchronously at a fixed angle, and at the same time drive the rollers 30 to rotate, leaving the gap 10, and ensuring that the center plane P1 of the next limiting groove 22 corresponding to the gap 10 coincides with the center plane P2 of the gap 10. In a preferred embodiment, the single rotation angle of the two circumferential retainers 2 is θ=360° / N, where N is the number of rollers 30.

[0034] S6. Repeat S4 and S5 until all rollers 30 are assembled.

[0035] Among them, in steps S4 and S6, the continuous transmission of the roller 30 can be achieved by transmitting the roller 30 through a dividing plate or a belt drive, and the feeding process of the roller 30 can be achieved by a robotic arm or other intelligent equipment.

[0036] S7. Remove the circumferential retainer 2 on one side, and sequentially install the retainer 33 and the elastic retainer 34 on that side using a robot or other intelligent equipment, then remove the circumferential retainer 2 on the other side, and sequentially install the retainer 33 and the elastic retainer 34 on that side, so that the screw 31, the roller 30, the retainer 33 and the elastic retainer 34 form an integrated module.

[0037] For step S7, when the retaining frame 33 is installed, it is necessary to ensure that the retaining frame 33 is coaxial with the lead screw 31, and each retaining hole on the retaining frame 33 is coaxial with the corresponding roller 30, so as to ensure assembly accuracy.

[0038] S8. A manipulator or other intelligent equipment can be used to clamp the integrated module, and the integrated module can be taken out in the axial direction until it is separated from the radial retainer 1, and then the integrated module can be screwed into the nut 32, and the assembly of the reverse planetary roller screw pair is completed.

[0039] It can be understood that in order to facilitate the convenient separation of the integrated module and the radial retainer 1 , the distance between the radial retainer 1 and the lead screw 31 should be greater than the outer diameter of the roller 30 .

[0040] In view of the technical problem that the existing assembly method of the planetary roller screw pair has defects, this embodiment simplifies the assembly process by using the radial retainer 1 and the circumferential retainer 2: quickly assemble the screw 31 and the roller 30 into an integrated module, and then quickly assemble the integrated module with the nut 32. This form can efficiently and conveniently realize the assembly of the screw 31 and the roller 30, while ensuring the transmission accuracy and performance of the reverse planetary roller screw pair, and improving the overall assembly efficiency of the reverse planetary roller screw pair. In addition, the radial retainer 1 and the circumferential retainer 2 have a simple structure and a simple assembly process, and are easy to match with intelligent equipment such as a robotic arm, thereby realizing industrial automated assembly.

[0041] The present invention and its embodiments are described schematically above, which is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and creatively designs a structure and an embodiment similar to the technical solution without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A method for assembling a reverse planetary roller screw pair, characterized in that: include: S1. Prepare a radial retainer (1) and a circumferential retainer (2): the radial retainer (1) is cylindrical, and is provided with a through notch (10); the circumferential retainer (2) comprises a barrel (20), an end block (21) is fixedly provided on one side of the barrel (20), and the end block (21) is provided with open limiting grooves (22) uniformly arranged along the circumferential direction, and the number of the limiting grooves (22) is the same as the number of the rollers (30); S2, arranging the two circumferential retainers (2) on both sides of one radial retainer (1) respectively: ensuring that the end block (21) on any circumferential retainer (2) is adjacent to the radial retainer (1); and ensuring that the center plane P1 of the limiting groove (22) corresponding to the notch (10) on any circumferential retainer (2) coincides with the center plane P2 of the notch (10); S3, install the lead screw (31) into the radial retainer (1) and the circumferential retainer (2), ensure that the lead screw (31), the radial retainer (1) and the circumferential retainer (2) are coaxially matched, ensure that the center plane P2 coincides with the plane P3 where the thread starting point R1 of the lead screw (31) is located, and clamp the lead screw (31) to ensure that the lead screw (31) is fixed; S4, push a roller (30) into the notch (10) until the optical axis section of the roller (30) is stuck in the limiting groove (22), and ensure that the end tooth section of the roller (30) and the end tooth section of the lead screw (31), as well as the thread section of the roller (30) and the thread section of the lead screw (31) are matched at the same time; S5, the two circumferential retainers (2) rotate synchronously at a fixed angle, and at the same time drive the roller (30) to rotate, leaving the notch (10) empty, and ensure that the center plane P1 of the next limiting groove (22) corresponding to the notch (10) coincides with the center plane P2 of the notch (10); S6, repeat S4 and S5 until all rollers (30) are assembled; S7, remove the circumferential retainer (2) on one side, and sequentially install the retainer (33) and the elastic retainer (34) on the side, then remove the circumferential retainer (2) on the other side, and sequentially install the retainer (33) and the elastic retainer (34) on the side, so that the lead screw (31), the roller (30), the retainer (33) and the elastic retainer (34) form an integrated module; S8. Screw the integrated module into the nut (32), and the assembly of the reverse planetary roller screw pair is completed.

2. The assembly method of a reverse planetary roller screw pair according to claim 1, characterized in that: For step S4, during the process of pushing the roller (30) into the notch (10), ensure that the thread starting point R1 of the screw (31) and the thread starting point R2 of the roller (30) are in the same plane, so that the end tooth section of the roller (30) and the end tooth section of the screw (31), as well as the thread section of the roller (30) and the thread section of the screw (31) are matched at the same time.

3. The assembly method of a reverse planetary roller screw pair according to claim 1, characterized in that: For step S5, the single rotation angle of the two circumferential retainers (2) is θ=360° / N, where N is the number of rollers (30).

4. The assembly method of a reverse planetary roller screw pair according to claim 1, characterized in that: For step S7, when the retaining frame (33) is installed, it is necessary to ensure that the retaining frame (33) is coaxial with the lead screw (31), and each retaining hole on the retaining frame (33) is coaxial with the corresponding roller (30).

5. The assembly method of a reverse planetary roller screw pair according to claim 1, characterized in that: An elastic card (4) is arranged at the opening of the limiting groove (22), and the distance between two elastic clips located in the same limiting groove (22) is smaller than the diameter of the optical axis section of the roller (30).

6. The assembly method of a reverse planetary roller screw pair according to claim 5, characterized in that: The limiting groove (22) is provided with a mounting groove (5), and the elastic card (4) is fixedly arranged in the mounting groove (5).

7. The assembly method of a reverse planetary roller screw pair according to claim 1, characterized in that: The outer diameter of the end block (21) is smaller than the inner diameter of the radial retainer (1).

8. The assembly method of a reverse planetary roller screw pair according to claim 1, characterized in that: The distance between the radial retainer (1) and the lead screw (31) is greater than the outer diameter of the roller (30).

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