Roller screw in external spiral circulation mode

Abstract

The utility model belongs to the technical field of rolling transmission, and particularly discloses a roller screw in an external spiral circulation mode, which comprises a screw, a screw spiral raceway with lead is arranged on the periphery of the screw, a nut spiral raceway matched with the screw spiral raceway is arranged on the inner periphery of a nut, and a return column pipe groove is arranged on the periphery of the nut. The nut spiral raceway and the lead screw spiral raceway are combined to form an inner roller raceway; the column return pipe is arranged on the outer side of the nut and is sleeved in the column return pipe groove in a penetrating manner, and the column return pipe forms an outer roller raceway and is provided with an inlet and an outlet which are communicated with the roller raceway; the outer roller raceway and the inner roller raceway have the same lead angle, and the base circle radius of the outer roller raceway is larger than the base circle radius of the inner roller raceway. According to the utility model, a longer circulation path curve is designed, so that the posture adjustment of the roller can be gradually completed in the circulation process, and the phenomena of jamming and wedging of the roller are reduced.

Description

Technical Field

[0001] This utility model belongs to the field of rolling transmission technology, specifically relating to a roller screw with an external helical circulation method. Background Technology

[0002] Roller screws are ideal products for converting rotary motion into linear motion, or linear motion into rotary motion. The screw generates line contact rolling friction through meshing rollers, which greatly increases the contact surface and force surface in the screw transmission process. Compared with ball screws, it has advantages such as high speed, high load, high rigidity, wide lead range, smaller size, lower noise, and easier maintenance and disassembly, without much loss of transmission efficiency. It has been widely used in mechatronics equipment.

[0003] However, unlike balls that can roll in any direction, rollers are restricted to a single direction, leading to numerous difficulties during the cyclic process. Current patent literature has explored this issue in depth. For example, patent application CN101842204A discloses a mixing and stirring degree adjustment mechanism, an extruder, a continuous mixing mixer, a mixing and stirring degree adjustment method, and a mixing and stirring method, including the construction of a structure similar to a ball screw end-face reversing device. This structure consists of two end-face guides connected by a straight tube with an inner square and an outer circle. However, in this type of structure, the roller needs to undergo a significant angle of attitude adjustment from entering the guide to leaving, and the radius of curvature of the channel curve is small. This undoubtedly greatly increases the possibility of the roller getting stuck or wedged. Utility Model Content

[0004] The purpose of this invention is to provide a roller screw with an external spiral circulation method, which is designed with a longer circulation path curve so that the roller can gradually complete the posture adjustment during the circulation process, reducing the phenomenon of the roller getting stuck or wedged.

[0005] The purpose of this utility model is achieved through the following technical solution: a roller screw with an external helical circulation method is provided, comprising:

[0006] The lead screw has a lead screw helical raceway with lead on its outer periphery;

[0007] The nut has an inner circumference with a nut helical raceway that mates with the lead screw helical raceway, and an outer circumference with a return column groove. The nut helical raceway and the lead screw helical raceway together form an inner roller raceway.

[0008] The return tube is located outside the nut and passes through the return tube groove. The return tube forms the outer roller raceway and has an inlet and an outlet that communicate with the roller raceway.

[0009] The outer roller raceway and the inner roller raceway have the same helix angle, and the base circle radius of the outer roller raceway is larger than that of the inner roller raceway.

[0010] Preferably, the return pipe includes an inlet section, a circulation spiral section, and an outlet section, with the inlet section and the circulation spiral section transitioning by an inlet transition section arc, and the outlet section and the circulation spiral section transitioning by an outlet transition section arc.

[0011] Preferably, the outer side of the return column tube is provided with an elastic protective layer.

[0012] Preferably, the nut includes a nut body and a clamping block. The nut body is provided with a first return tube groove, and the clamping block is provided with a second return tube groove that mates with the first return tube groove.

[0013] Preferably, the helix angle is 5.05°.

[0014] Due to the adoption of the above technical solution, this utility model has the following advantages:

[0015] The outer roller raceway and the inner roller raceway have the same helix angle, and the roller rolling path has a constant curvature, avoiding jamming caused by sudden changes in curvature. The outer roller raceway is constructed by setting a return tube, in which the roller gradually adjusts its posture. The base circle radius of the outer roller raceway is larger than that of the inner roller raceway and has the opposite direction of rotation. The increased curvature radius of the outer roller raceway provides sufficient space for the roller to adjust its posture during the cycle, avoiding jamming problems caused by a smaller curvature radius. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0017] Figure 1 This is a schematic diagram of the structure of a roller screw with an external spiral circulation method according to the present invention;

[0018] Figure 2 This is a schematic diagram of the return column pipe;

[0019] Figure 3 This is a schematic diagram of the nut body;

[0020] Figure 4 This is a schematic diagram of the clamping block;

[0021] Figure 5 This is a schematic diagram of the helix of the lead screw helical raceway and the outer roller raceway.

[0022] Figure label:

[0023] 1-Screw, 11-Screw spiral raceway, 12-Inner roller raceway;

[0024] 2-Nut, 21-Nut spiral raceway, 22-Return column groove, 23-Nut body, 231-First return column groove, 24-Clamping block, 241-Second return column groove;

[0025] 3-Return column tube, 31-Outer roller raceway, 32-Inlet, 33-Outlet, 34-Inlet section, 35-Circulating spiral section, 36-Outlet section, 37-Inlet transition section, 38-Outlet transition section, 39-Elastic protective layer; 4-Roller. Detailed Implementation

[0026] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0027] Please see Figure 1 A type of roller screw with an external helical circulation method includes: screw 1, nut 2 and return tube 3.

[0028] A lead screw helical raceway 11 with a lead is provided on the outer periphery of the lead screw 1; a nut helical raceway 21 that mates with the lead screw helical raceway 11 is provided on the inner periphery of the nut 2; and a return tube groove 22 is provided on the outer periphery of the nut 2. The nut helical raceway 21 and the lead screw helical raceway 11 together form an inner roller raceway 12; a return tube 3 is provided on the outside of the nut 2 and passes through the return tube groove 22, forming an outer roller raceway 31, which has an inlet 32 ​​and an outlet 33 communicating with the roller raceway 12; the outer roller raceway 31 and the inner roller raceway 12 have the same helix angle, and the base circle radius of the outer roller raceway 31 is larger than the base circle radius of the inner roller raceway 12. Specifically, the nut 2 and the return tube 3 are integrally formed; or the nut 2 and the return tube 3 are separate parts, please refer to [reference needed]. Figure 3 and Figure 4The nut 2 includes a nut body 23 and a clamping block 24. The nut body 23 has a first return tube groove 231, and the clamping block 24 has a second return tube groove 241 that mates with the first return tube groove 231. The first return tube groove 231 and the second return tube groove 241 constitute a return tube groove 22, in which the return tube 3 is installed. Before installation, the nut body 23 and the clamping block 24 are separate. First, the return tube 3 is placed in the first return tube groove 231, and then steel glue is applied to the surface of the nut body 23 except for the first return tube groove 231. The clamping block 24 is connected to the nut body 23 by steel glue, which facilitates the installation of the return tube 3 and the roller 4. Multiple rollers 4 are arranged sequentially in the inner roller raceway 12 and the outer roller raceway 31, and while rotating on their own axis, they revolve around the lead screw along the inner roller raceway 12 and the return tube 3. As the roller 4 runs in the inner roller raceway 12, its motion remains unchanged. Within the outer roller raceway 31, its posture is gradually adjusted so that the roller 4's posture at the inlet 32 ​​matches its posture at the outlet 33, thus enabling the roller 4 to smoothly complete its cycle. The outer roller raceway 31 rotates in the opposite direction to the inner roller raceway 12.

[0029] The present invention relates to a roller screw with an external spiral circulation method. When the screw 1 and nut 2 are subjected to external force, the roller 4 is driven to roll by friction in the inner roller raceway 12 and the outer roller raceway 31. Roller 4 enters the outer roller raceway 31 from the inlet 32 ​​and then enters the inner roller raceway 12 from the outlet 33. During this process, the outer roller raceway 31 and the inner roller raceway 12 have the same helix angle, and the rolling path of roller 4 has a constant curvature, avoiding jamming caused by sudden curvature changes. The attitude is gradually adjusted by the outer roller raceway 31. The base circle radius of the outer roller raceway 31 is larger than that of the inner roller raceway 12 and has the opposite direction of rotation. The increased curvature radius of the outer roller raceway 31 provides sufficient space for attitude adjustment of roller 4 during the cycle, avoiding jamming caused by a small curvature radius. By setting the inner roller raceway 12 and the outer roller raceway 31 to have the same lead angle, different base circle radii, and opposite directions of rotation, this application can enhance the synchronous rolling and continuous cycle of roller 4. By using matching helices with opposite directions of rotation, the roller 4 is seamlessly connected between the lead screw 1 and the return tube 3. Combined with friction drive, the roller achieves continuous and stable circulation, enhancing the system's load-bearing capacity and reliability.

[0030] Further, please refer to Figure 2The return column tube 3 includes an inlet section 34, a circulating spiral section 35, and an outlet section 36. The inlet section 34 and the circulating spiral section 35 are connected by an inlet transition section 37 with an arc, and the outlet section 36 and the circulating spiral section 35 are connected by an outlet transition section 38 with an arc. Specifically, the inlet section 34 has an inlet 32 ​​at the end away from the circulating spiral section 35, and the outlet section 36 has an outlet 33 at the end away from the circulating spiral section 35. Both the inlet 32 ​​and the outlet 33 are connected to the screw spiral raceway 11, and under the action of the inlet transition section 37 and the outlet transition section 38, the posture of the roller 4 at the inlet 32 ​​is consistent with the posture at the outlet 33. When the lead screw 1 and nut 2 rotate relative to each other, the roller 4 enters the inlet transition section 37 through the inlet 32 ​​from the lead screw helical raceway 11. After adjusting its posture in the inlet transition section 37, it enters the circulating helical section 35, where it helically moves. Then, after adjusting its posture again in the outlet transition section 38, it enters the outlet section 36 and finally enters the lead screw helical raceway 11 from the outlet 33, completing the closed-loop cycle of the roller 4. The use of a circular arc transition helps to ensure smooth curvature changes and a natural path transition. This design combines the high load-bearing characteristics of the roller's line contact with the smooth transition of the helical path, ensuring the smoothness, stability, and high load-bearing capacity of the roller 4's circulation process.

[0031] Further, please refer to Figure 1 An elastic protective layer 39 is provided on the outer side of the return tube 3. Preferably, the elastic protective layer 39 is a thin layer of soft silicone. With this structure, not only does the return tube 3 come into close contact with the inner wall of the return tube groove 22, but it also helps to reduce the external force on the roller 4 and improve the smooth rolling of the roller 4.

[0032] Further, please refer to Figure 5 The helix angle λ is 5.05°. Specifically, in this application, the nominal diameter do of the lead screw helical raceway 11 is 36mm, the lead Ph is 10mm, and the nominal diameter d1 of the outer roller raceway is 56mm. According to the formula: λ = arctanPh / (π × do) = arctan10 / (π × 36) = 5.05°. The helix angle λ of 5.05° can improve the synchronous rolling and continuous circulation of the roller 4. The inner roller raceway 12 and the outer roller raceway 31 have opposite helical directions, thereby ensuring that the roller 4 can smoothly enter the return tube 3.

[0033] This invention discloses a roller screw with an external spiral circulation method. The circulating raceway of the roller is configured as a return tube 3 wound around the outside of the nut 2. The spiral circulation path of the return tube 3 not only has a constant curvature but also an increased radius of curvature. When the screw 1 and the nut 2 rotate relative to each other, the roller 4 is driven to roll by friction in the inner roller raceway 12. The roller 4 passes sequentially from the inlet 32 ​​through the inlet section 34, the inlet transition section 37, the circulating spiral section 35, the outlet transition section 38, and the outlet section 36, and then enters the inner roller raceway 12 through the outlet 33, completing a continuous cycle. During this process, the spiral circulation path of the return tube 3 not only has a constant curvature but also an increased radius of curvature. Furthermore, the two-stage arc transition design allows the roller to gradually adjust its posture, providing ample space for posture adjustment during the circulation process. This application enhances the synchronous rolling and continuous circulation of the roller 4 by setting the inner roller raceway 12 and the outer roller raceway 31 to have the same lead angle, different base circle radii, and opposite directions of rotation. By using matching helices with opposite directions of rotation, the roller 4 is seamlessly connected between the lead screw 1 and the return tube 3. Combined with friction drive, the roller achieves continuous and stable circulation, enhancing the system's load-bearing capacity and reliability.

[0034] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific implementation method of this utility model and is not intended to limit this utility model. Any modifications, equivalent substitutions, and improvements made within the scope of the spirit of this utility model should be included within the protection scope of this utility model.

Claims

1. A roller screw with an external helical circulation method, characterized in that, include: The lead screw (1) has a lead screw helical raceway (11) with a lead around its outer periphery. The nut (2) has a nut spiral raceway (21) on its inner circumference that matches the screw spiral raceway (11), and a return column groove (22) on its outer circumference. The nut spiral raceway (21) and the screw spiral raceway (11) together form an inner roller raceway (12). The return tube (3) is located outside the nut (2) and is sleeved in the return tube groove (22). The return tube (3) forms the outer roller raceway (31), and its two ends are respectively provided with an inlet (32) and an outlet (33) that communicate with the roller raceway (12). The outer roller raceway (31) and the inner roller raceway (12) have the same helix angle, and the base circle radius of the outer roller raceway (31) is larger than that of the inner roller raceway (12).

2. The roller screw with external helical circulation according to claim 1, characterized in that, The return pipe (3) includes an inlet section (34), a circulation spiral section (35) and an outlet section (36). The inlet section (34) and the circulation spiral section (35) are connected by an inlet transition section (37) with an arc, and the outlet section (36) and the circulation spiral section (35) are connected by an outlet transition section (38) with an arc.

3. The roller screw with external helical circulation according to claim 1 or 2, characterized in that, An elastic protective layer (39) is provided on the outside of the return column tube (3).

4. The roller screw with external helical circulation according to claim 1 or 2, characterized in that, The nut (2) includes a nut body (23) and a clamping block (24). The nut body (23) is provided with a first return tube groove (231), and the clamping block (24) is provided with a second return tube groove (241) that cooperates with the first return tube groove (231).

5. The roller screw with external helical circulation according to claim 3, characterized in that, The nut (2) includes a nut body (23) and a clamping block (24). The nut body (23) is provided with a first return tube groove (231), and the clamping block (24) is provided with a second return tube groove (241) that cooperates with the first return tube groove (231).

6. The roller screw with external helical circulation according to claim 1, 2 or 5, characterized in that, The helix angle is 5.05°.

7. The roller screw with external helical circulation according to claim 4, characterized in that, The helix angle is 5.05°.

Images