Linear motion mechanism

Abstract

The utility model discloses a linear motion mechanism, and belongs to the technical field of transmission mechanisms. The anti-backlash device comprises a guide block and a rack penetrating through the guide block in a sliding mode, the rack is provided with at least one guide plane deviating from a rack meshing part, a flexible anti-backlash piece is arranged on the guide block, and the flexible anti-backlash piece abuts against the guide plane in a sliding mode. According to the linear motion mechanism, the flexible anti-backlash piece is arranged on the guide block and slidably abuts against the guide plane of the rack, shaking of the rack in the circumferential direction is effectively eliminated, the motion stability of the linear motion mechanism is improved, the fit clearance between the guide block and the rack can be properly widened by using the flexible anti-backlash piece, and the machining difficulty and cost are reduced.

Description

Technical Field

[0001] This application relates to the technical field of transmission mechanisms, and in particular to a linear motion mechanism. Background Technology

[0002] Currently, there are many linear motion mechanisms on the market, among which rack and pinion linear mechanisms account for a large proportion. However, traditional rack and pinion mechanisms require additional guiding mechanisms, such as guide rails and guide shafts, which increases the cost and size of the linear motion mechanism.

[0003] In related technologies, patent CN208221508U discloses a linear transmission device for a cylindrical rack module used in automated design. It includes a cylindrical rack and a gearbox. The gearbox includes a housing, bearings, bearing sleeves, guide sleeves, a positioning ring, and gears. The cylindrical rack and gears mesh, and both have straight tooth shapes. The gearbox has a first through hole and a second through hole. The guide sleeve and positioning ring are located in the first through hole, the cylindrical rack is located in the guide sleeve, and the bearings, bearing sleeves, and gears are located in the second through hole. Each face of the gearbox has four corners with second threaded holes. This utility model's transmission device uses a cylindrical rack and gear combination, which has a simple structure, transmits large power, has a fast transmission speed, and operates smoothly and reliably. The gearbox contains a guide sleeve, which provides excellent guidance and high straightness. The gearbox has a compact internal structure, high load-bearing capacity, small space occupation, and oil holes for simple lubrication.

[0004] The aforementioned technologies primarily utilize a guide sleeve installed within the first through hole to guide the cylindrical rack. However, the rack is generally quite long, making it difficult to ensure consistent thickness throughout the rack during machining (high machining precision is required to maintain this consistency). If the gap between the rack and the guide sleeve is too large, the rack will wobble significantly in the circumferential direction. Conversely, if the gap is too small, the straightness requirement for the rack becomes excessively high; otherwise, the rack may jam during operation. Utility Model Content

[0005] To reduce the machining difficulty of the rack and eliminate its circumferential wobble, this application provides a linear motion mechanism.

[0006] The linear motion mechanism provided in this application adopts the following technical solution:

[0007] A linear motion mechanism includes a guide block and a rack that slides through the guide block, wherein the rack has at least one guide plane opposite to the rack engagement portion, and a flexible backlash elimination plate is provided on the guide block, the flexible backlash elimination plate slidingly abutting against the guide plane.

[0008] By adopting the above technical solution, the guide plane ensures that the linear motion mechanism can achieve stable rack movement without the need for an additional guide mechanism. Specifically, the flexible backlash-free plate on the guide block slides and abuts against the guide plane of the rack, effectively solving the circumferential wobbling problem existing in traditional gear and rack mechanisms, reducing the requirements for rack straightness, reducing machining difficulty, and ensuring the smoothness and accuracy of the rack during movement.

[0009] Optionally, the flexible gap-eliminating plate includes a mounting portion and an arc-shaped portion. The mounting portion is detachably connected to the guide block, and the arc-shaped portion is located on one side of the mounting portion, with the outward protrusion of the arc-shaped portion slidingly abutting against the guide plane.

[0010] By adopting the above technical solution, the structural design of the flexible backlash elimination plate is enhanced, allowing for convenient and detachable connection between the flexible backlash elimination plate and the guide block via the mounting part. Simultaneously, the arc-shaped design ensures that the outward convexity of the arc-shaped portion better conforms to the guide plane, thereby effectively reducing circumferential wobbling of the rack during movement and improving motion stability.

[0011] Optionally, the flexible gap-eliminating plate has an adjustment hole extending in a direction perpendicular to the guide plane, and the flexible gap-eliminating plate and the guide block are detachably connected by a fastener passing through the adjustment hole.

[0012] By adopting the above technical solution, the position of the flexible backlash elimination plate can be adjusted in a direction perpendicular to the guide plane, which facilitates the precise elimination of circumferential wobble of the rack in the guide block, improves the stability of rack movement, and reduces processing difficulty.

[0013] Optionally, the flexible gap-eliminating plates are configured in at least two sets, with the two sets of flexible gap-eliminating plates spaced apart along the length direction of the rack.

[0014] By adopting the above technical solution, backlash can be eliminated at multiple points during the rack sliding process, thereby more effectively eliminating the rack's circumferential wobble and ensuring the smoothness and accuracy of the motion process.

[0015] Optionally, the motion mechanism further includes an actuator motor, the output end of which is equipped with a gear that meshes with the rack, a position sensor is provided on the side of the guide block, a sensor detection piece is installed at the end of the rack, the position sensor is electrically connected to the actuator motor, and the sensor detection piece can trigger the position sensor.

[0016] By adopting the above technical solution, the position sensor is set on the side of the guide block and electrically connected to the actuator motor. The sensor detection plate installed at the end of the rack can trigger the position sensor when it moves forward or backward to the limit position, thereby realizing precise control of the rack's movement stroke, avoiding mechanical damage caused by exceeding the stroke, and improving the reliability and accuracy of the movement.

[0017] Optionally, a base may be detachably mounted on the side of the guide block, and the position sensor may be mounted on the base.

[0018] By adopting the above technical solution, the position sensor can be installed on the base more flexibly, which facilitates the adjustment and maintenance of the position sensor. At the same time, it simplifies the overall structure of the linear motion mechanism and improves the installation efficiency.

[0019] Optionally, a position fixing plate is provided on the side of the base.

[0020] By adopting the above technical solution, the entire linear motion mechanism can be fixed in a certain position by a position fixing plate, thereby enhancing the flexibility of the linear motion mechanism's position installation.

[0021] Optionally, a reduction gearbox is provided between the actuator motor and the gear, and the output end of the actuator motor is connected to the gear through the reduction gearbox, with the gear located inside the guide block.

[0022] By adopting the above technical solution, this design can effectively reduce the speed of the gears, increase the torque output, and ensure the smoothness and accuracy of the linear motion mechanism during operation. At the same time, placing the gears in the guide block can also protect the gears and enhance the durability of the entire mechanism.

[0023] Optionally, the guide block has a through hole that penetrates its own sidewall, and the gear is located inside the through hole so that part of the gear structure is exposed outside the through hole.

[0024] By adopting the above technical solution, oil can be directly injected into the gears through the through hole, enhancing the convenience of maintenance.

[0025] Optionally, the guide block has screw mounting holes on its side.

[0026] By adopting the above technical solution, the guide block can be easily installed in the required position using screws, thereby improving the installation convenience and stability of the entire linear motion mechanism.

[0027] In summary, this application includes at least one of the following beneficial technical effects:

[0028] 1. By setting a flexible backlash-eliminating plate on the guide block and sliding it against the guide plane of the rack, the circumferential wobbling of the rack is effectively eliminated, improving the motion stability of the linear motion mechanism. The use of the flexible backlash-eliminating plate can appropriately widen the fit clearance between the guide block and the rack, reducing the processing difficulty and cost.

[0029] 2. By setting up position sensors and sensor detection plates, precise detection and limitation of the rack's extreme positions can be achieved, improving the accuracy and reliability of linear motion mechanisms.

[0030] 3. The position of the flexible backlash elimination plate can be adjusted in a direction perpendicular to the guide plane, which facilitates the precise elimination of circumferential wobble of the rack in the guide block, improves the stability of rack movement, and reduces the processing difficulty. Attached Figure Description

[0031] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application.

[0032] Figure 2 yes Figure 1 An enlarged schematic diagram of part A in the middle.

[0033] Figure 3 This is a schematic diagram of the flexible gap-eliminating plate with adjustment holes according to an embodiment of this application.

[0034] Figure 4 This is a schematic diagram of the structure of the through hole inside the guide block, which is the main feature of this application embodiment.

[0035] Explanation of reference numerals in the attached figures:

[0036] 10. Guide block; 11. Through hole; 12. Screw mounting hole; 20. Rack; 21. Guide plane; 30. Flexible backlash elimination plate; 301. Adjustment hole; 31. Mounting part; 32. Arc-shaped part; 40. Fastener; 50. Actuating motor; 51. Gearbox; 60. Gear; 70. Position sensor; 71. Sensor detection plate; 711. Forward sensor detection plate; 712. Backward sensor detection plate; 80. Base; 81. Position fixing plate. Detailed Implementation

[0037] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0038] The linear motion mechanism provided in this application embodiment refers to... Figure 1 and Figure 2The linear motion mechanism includes a guide block 10 and a rack 20 that slides through the guide block 10. The rack 20 has at least one guide plane 21 that is opposite to the meshing part of the rack 20. A flexible backlash elimination plate 30 is provided on the guide block 10. The flexible backlash elimination plate 30 slides against the guide plane 21, which makes the linear motion mechanism structure simpler and reduces costs.

[0039] Specifically, the guide block 10 has a guide hole. In this embodiment, the guide hole is D-shaped and is used to mate with the guide plane 21 on the rack 20. In other embodiments, the guide hole can be designed as a square hole or other irregularly shaped hole in addition to a D-shaped hole to achieve the same guiding function. The inner side of the guide hole can be precision machined by grinding to make its contact with the guide plane 21 of the rack 20 tighter and smoother, reducing frictional resistance.

[0040] In one embodiment, the flexible gap-eliminating plate 30 includes a mounting portion 31 and an arc-shaped portion 32. The mounting portion 31 is mainly used for detachable connection with the guide block 10, and can be connected by screws, clips, or any other suitable connection method. The arc-shaped portion 32 is located on one side of the mounting portion 31, and its outer convex surface slides against the guide plane 21. Preferably, the mounting portion 31 and the arc-shaped portion 32 are integrally formed. In this way, even if wear occurs between the guide plane 21 and the guide hole during long-term use, the arc-shaped flexible gap-eliminating plate 30 can still provide a good gap-eliminating effect. Specifically, the flexible gap-eliminating plate 30 can be made of rubber, silicone, polyurethane, or other materials with good elasticity and wear resistance to ensure its long-term performance. In addition, the outer convex surface of the flexible gap-eliminating plate 30 can be designed with different radii of curvature according to actual needs to adapt to guide planes 21 of different sizes, ensuring that it always maintains a good contact state with the guide surface.

[0041] Reference Figure 3 In another embodiment, the flexible gap-eliminating plate 30 has an adjustment hole 301 extending in a direction perpendicular to the guide plane 21. The flexible gap-eliminating plate 30 and the guide block 10 are detachably connected by a fastener 40 passing through the adjustment hole 301. This design allows the position of the flexible gap-eliminating plate 30 to be easily adjusted according to actual usage. The adjustment hole 301 can be an elongated hole or an elliptical hole, etc., to facilitate fine-tuning of the compression of the flexible gap-eliminating plate 30 to ensure that it always maintains appropriate pressure with the guide plane 21. For example, the fastener 40 can be a self-locking screw to prevent loosening and ensure a continuous and stable gap-eliminating effect.

[0042] Reference Figure 4To further improve the reliability of the entire linear motion mechanism, at least two sets of flexible backlash elimination plates 30 are provided, spaced apart along the length of the rack 20. This arrangement effectively reduces uneven friction caused by single-point elastic elements, making the rack 20 more stable during movement. The distance between the two sets of flexible backlash elimination plates 30 can be rationally designed according to the length of the rack 20 and the specific load conditions of the application to achieve the best backlash elimination effect. For example, the first set of flexible backlash elimination plates 30 is close to the front end of the rack 20, and the second set is close to the rear end of the rack 20, with a spacing of approximately one-third of the total length of the rack 20, to evenly distribute the load.

[0043] Reference Figure 1 In other specific cases, the linear motion mechanism also includes an actuator motor 50, which is fixed to the guide block 10. A gear 60 is mounted on the output end of the actuator motor 50, meshing with a rack 20. A position sensor 70 is mounted on the side of the guide block 10, and a sensor detection piece 71 is mounted on the end of the rack 20. The sensor detection piece 71 includes a forward sensor detection piece 711 and a backward sensor detection piece 712 respectively located at both ends of the rack 20. The position sensor 70 is electrically connected to the actuator motor 50, and the sensor detection piece 71 can trigger the position sensor 70. Thus, by controlling the start and stop of the actuator motor 50 through the position sensor 70 on the side of the guide block 10, overtravel of the rack 20 can be prevented, and the movement position of the rack 20 can be effectively detected and controlled.

[0044] The aforementioned sensors can be photoelectric or Hall effect sensors, capable of detecting the extreme positions of the rack 20. Different types of sensors have different response speeds and accuracy characteristics; the appropriate sensor must be selected based on the actual application scenario during the design process. The mounting position of the sensor detection piece 71 can be adjusted according to the actual stroke length to ensure that the position sensor 70 can accurately send a signal when approaching the extreme position, thereby stopping the movement in time to protect the entire mechanism. The thickness of the sensor detection piece 71 is generally no more than 2 mm, and the material is a thin metal sheet or a non-metallic insulating sheet to avoid affecting the overall motion accuracy.

[0045] In other embodiments, to improve the adaptability of the overall mechanism, a base 80 is detachably mounted on the side of the guide block 10, and the position sensor 70 is mounted on the base 80. This mounting method facilitates the disassembly, assembly, and adjustment of the position sensor 70. The base 80 is located on one side of the guide block 10, and multiple threaded holes are provided on the side of the base 80, allowing the entire device to be precisely fixed to the guide block 10 using screws or other fixing devices. This design allows users to flexibly adjust the position of the base 80 according to actual needs, and also facilitates future maintenance and replacement.

[0046] In fact, a position fixing plate 81 is provided on the side of the base 80, which can be fastened to the workbench or other platform with screws. This further ensures that the linear motion mechanism can maintain a stable state even after long-term operation. The specific form of the position fixing plate 81 can be designed as an L-shaped plate or a rectangular plate, etc., according to the actual situation, and can be made of different materials such as galvanized steel plate or plastic composite material. The surface can be powder coated or electroplated as required to enhance corrosion resistance.

[0047] In this embodiment, a reduction gearbox 51 is provided between the actuator motor 50 and the gear 60. The output end of the actuator motor 50 is connected to the gear 60 via the reduction gearbox 51, and the gear 60 is located within the guide block 10. The presence of the reduction gearbox 51 enables the high-speed rotating actuator motor 50 to output smoother rotation and greater low-speed torque, thereby improving the load-bearing capacity and motion accuracy of the entire mechanism. The internal structure of the reduction gearbox 51 can be customized by selecting different types of gears 60 (such as helical gears or bevel gears) and transmission ratios to meet the speed and torque requirements under different working conditions.

[0048] Reference Figure 1 and Figure 4 To improve the overall compactness of the mechanism, the guide block 10 has a through hole 11 that extends through its own sidewall. The gear 60 is located inside the through hole 11, so that part of the gear 60 structure is exposed outside the through hole 11. This design saves space and facilitates subsequent maintenance and repair. In addition, the through hole 11 can also extend through the base 80, and a sealing cap can be installed at the through hole 11 of the base 80 to seal it.

[0049] To facilitate alignment of positioning points during subsequent assembly, screw mounting holes 12 are provided on the side of the guide block 10. These holes allow screws to be used to fix the guide block 10 to various equipment or bases. To accommodate equipment of different sizes, the size, number, and distribution of the screw mounting holes 12 can be flexibly selected according to specific application conditions. The surface of the screw mounting holes 12 is smoothed to enhance the reliability of the screw connection. In certain special cases, threaded sleeves or other reinforcing devices can be pre-embedded at the locations of the screw mounting holes 12 to ensure a more secure fixation.

[0050] Furthermore, the guide block 10 and the base 80 can be combined into one part. In actual use, it can be decided whether to combine them according to specific needs.

[0051] The implementation principle of this embodiment is as follows: by using a special guide block 10 design to replace the traditional complex guide system, the guiding and constraint functions of the rack 20 are integrated, simplifying the structure of the entire linear transmission device, reducing costs and size. The introduction of the flexible backlash-eliminating plate 30 not only reduces the machining accuracy requirements of the rack 20, but also significantly improves the smoothness of motion. In addition, the innovative configuration of various auxiliary components (such as the actuator motor 50 and the position sensor 70) further enhances the overall performance of the linear motion mechanism.

[0052] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A linear motion mechanism, characterized in that, The device includes a guide block (10) and a rack (20) that slides through the guide block (10). The rack (20) has at least one guide plane (21) that is opposite to the meshing part of the rack (20). A flexible backlash elimination plate (30) is provided on the guide block (10), and the flexible backlash elimination plate (30) slides against the guide plane (21).

2. The linear motion mechanism according to claim 1, characterized in that: The flexible gap-eliminating plate (30) includes a mounting part (31) and an arc-shaped part (32). The mounting part (31) is detachably connected to the guide block (10). The arc-shaped part (32) is located on one side of the mounting part (31), and the outward protrusion of the arc-shaped part (32) slides against the guide plane (21).

3. A linear motion mechanism according to claim 1 or 2, characterized in that: The flexible gap-eliminating plate (30) has an adjustment hole (301) extending in a direction perpendicular to the guide plane (21), and the flexible gap-eliminating plate (30) and the guide block (10) are detachably connected by a fastener (40) passing through the adjustment hole (301).

4. A linear motion mechanism according to claim 1, characterized in that: The flexible gap-eliminating plates (30) are configured in at least two groups, and the two groups of flexible gap-eliminating plates (30) are spaced apart along the length direction of the rack (20).

5. A linear motion mechanism according to claim 1, characterized in that: The motion mechanism also includes an actuator motor (50), the output end of which is equipped with a gear (60), which meshes with the rack (20). A position sensor (70) is provided on the side of the guide block (10), and a sensor detection piece (71) is installed at the end of the rack (20). The position sensor (70) is electrically connected to the actuator motor (50), and the sensor detection piece (71) can trigger the position sensor (70).

6. A linear motion mechanism according to claim 5, characterized in that: The guide block (10) has a base (80) detachably mounted on its side, and the position sensor (70) is mounted on the base (80).

7. A linear motion mechanism according to claim 6, characterized in that: A position fixing plate (81) is provided on the side of the base (80).

8. A linear motion mechanism according to claim 5, characterized in that: A reduction gearbox (51) is provided between the actuator (50) and the gear (60). The output end of the actuator (50) is connected to the gear (60) through the reduction gearbox (51). The gear (60) is located inside the guide block (10).

9. A linear motion mechanism according to claim 5, characterized in that: The guide block (10) has a through hole (11) that penetrates its own side wall, and the gear (60) is located inside the through hole (11) so that part of the structure of the gear (60) is exposed outside the through hole (11).

10. A linear motion mechanism according to claim 1, characterized in that: The guide block (10) has a screw mounting hole (12) on its side.

Images