Double-support low-return-difference cycloidal speed reducer for small swing arm robot

Abstract

The double-support low-return-difference cycloidal speed reducer comprises a needle shell, a framework oil seal is movably connected to the left side of the interior of the needle shell in a clamped mode, a rear planet carrier and a front planet carrier are arranged on the left side and the right side of the interior of the needle shell respectively, and deflection structures are arranged between the rear planet carrier and the needle shell and between the front planet carrier and the needle shell. A hexagon socket cap screw is fixedly installed between the rear planet carrier and the front planet carrier, an input gear shaft is arranged on the inner side of the rear planet carrier and the inner side of the front planet carrier, and a transmission structure is arranged on the surface of the input gear shaft. According to the double-support low-return-difference cycloid speed reducer for the small swing arm robot, the input gear shaft is fixedly connected with an external power source and can drive the transmission structure to rotate, so that the transmission structure can drive the deflection structure to rotate, and the speed reducer can stably work with large torque.

Description

Technical Field

[0001] The utility model relates to the technical field of reducers, in particular to a double-support low-backlash cycloid reducer for a small swing-arm robot. Background Art

[0002] The RV (rotor-vector) drive for robots (a crank-type closed differential gear train) is a new type of transmission developed based on the cycloid drive. Its key features are three key advantages (high transmission ratio, high load capacity, and high rigidity), two key advantages (high motion precision and high transmission efficiency), and one key advantage (low backlash). Compared to simple cycloid planetary drives, it offers a smaller package, greater overload capacity, and greater output shaft rigidity. Consequently, it has gained widespread attention both domestically and internationally, and has largely replaced simple cycloid planetary drives and harmonic drives in Japanese robot transmissions. The RV drive has two extremely stringent technical specifications: transmission error must not exceed 1'; and backlash must not exceed 1' to 1.5', depending on the RV reducer model. Furthermore, when operating under rated load, the total backlash, including backlash caused by elastic deformation, must not exceed 6'.

[0003] Since the high-precision cycloid differential gear reducer used in robots has a large load and high transmission accuracy, how to design an RV reducer with small size, high precision and low vibration has become a difficult problem faced today.

[0004] Patent publication number CN117823577B discloses a robotic backlash-eliminating double-cycloid hollow reducer. This device aims to address the complex structure, large size, and high manufacturing precision requirements of traditional RV reducers. Through optimized design, it achieves high efficiency, light weight, smooth operation, and low noise. However, despite the numerous improvements made in this patent, achieving high-precision cycloid differential gear reducers with high load capacity and transmission accuracy while still requiring a smaller size, improved precision, and reduced vibration remains a challenge. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the utility model provides a double-support low-backlash cycloid reducer for a small swing-arm robot, which solves the problems of low crankshaft strength, poor impact resistance and unstable output.

[0006] In order to achieve the above-mentioned purpose of high crankshaft strength, good impact resistance and stable output, the utility model provides the following technical solutions: a double-support low backlash cycloid reducer for a small swing arm robot, comprising a needle housing, a skeleton oil seal is movably clamped on the left side of the interior of the needle housing, a rear planetary carrier and a front planetary carrier are respectively provided on the left and right sides of the interior of the needle housing, a deflection structure is provided between the rear planetary carrier and the front planetary carrier and the needle housing, a hexagon socket head screw is fixed between the rear planetary carrier and the front planetary carrier, an input gear shaft is provided on the inner side of the rear planetary carrier and the front planetary carrier, and a transmission structure is provided on the surface of the input gear shaft;

[0007] The transmission structure includes planetary gear washers, planetary gears, sun gears, and input shaft washers. The input shaft washers are movably connected to the left and right ends of the input gear shaft. The input shaft washers are located inside the rear planet carrier and the front planet carrier. The sun gears are installed on the surface of the input gear shaft. The planetary gears are provided in three groups, and the three groups of planetary gears are meshed with the sun gears. The planetary gear washers are provided on both sides of the planetary gears.

[0008] The deflection structure includes a needle roller, an angular contact ball bearing, a rear cycloid wheel, a front cycloid wheel, a hole retaining ring, a tapered roller bearing, a steel cage needle roller, an eccentric shaft gasket and an eccentric shaft, the planetary gear gasket is movably clamped on the eccentric shaft, the planetary gear is mounted on the surface of the eccentric shaft, and the planetary gear is fixedly connected to the eccentric shaft through the planetary gear gasket. The needle roller is arranged inside the tooth groove on the inner wall of the needle housing, the angular contact ball bearing is movably connected at the port of the needle housing, the angular contact ball bearing is located between the needle housing and the rear planetary carrier and the front planetary carrier, the steel cage needle roller is arranged inside the end face through-hole of the rear cycloid wheel and the front cycloid wheel, the rear cycloid wheel and the front cycloid wheel are sleeved on the surface of the eccentric shaft through the steel cage needle roller, hole retaining rings are provided on both sides of the tapered roller bearing, the tapered roller bearing is mounted on the eccentric shaft through the hole retaining ring, and the tapered roller bearing is located between the eccentric shaft and the rear planetary carrier and the front planetary carrier.

[0009] Preferably, the number of teeth of the sun tooth is 20, the module is 1.25, the pressure angle is 20°, and the tooth width is 9.3 mm.

[0010] Preferably, the planetary gear has 34 teeth, a module of 1.25, a pressure angle of 20°, and a tooth width of 6 mm.

[0011] Preferably, the eccentricity of the eccentric shaft is 1.1 mm.

[0012] Preferably, the number of teeth of the rear cycloid wheel and the front cycloid wheel is 39, the outer diameter of the needle gear sleeve is Φ5mm, the eccentricity is 1.1mm, the center circle diameter of the needle wheel is Φ118mm, and the tooth width is 12mm.

[0013] Preferably, the outer diameter of the needle roller is Φ5 mm and the length is 23.8 mm.

[0014] Preferably, the needle housing has 40 teeth, the center circle diameter is Φ118 mm, and the needle teeth diameter is Φ5 mm.

[0015] Compared with the existing technology, the utility model provides a double-support low-backlash cycloid reducer for a small swing-arm robot, which has the following beneficial effects:

[0016] This small swing-arm robot uses a double-support, low-backlash cycloid reducer. The cycloid gear in this structure uses a single-difference gear structure, resulting in better meshing accuracy than a double-difference gear structure. The cycloid gear, needle roller, and needle housing all experience rolling friction contact, resulting in excellent rigidity. The input shaft is mated to a splined shaft and involute sun gear splines. The spline shaft utilizes a double-support structure, resulting in stable transmission and low vibration. The single-difference gear structure makes it easier to achieve high drive train error and backlash requirements, resulting in greater rigidity and reduced backlash, thus preventing jitter and excessive damping vibration during reducer operation. The planetary carrier utilizes a columnar taper pin connection structure, characterized by its simple structure, easy machining, and high strength. Furthermore, the high-precision taper pin connection ensures consistent machining and assembly.

[0017] 2. The small swing arm robot uses a double-support low-backlash cycloid reducer, which has the characteristics of reasonable structure, small size, high efficiency and low vibration. The advantages of this utility model are that it optimizes the structural design, facilitates parts assembly, and improves the assembly accuracy of the reducer. At the same time, it has the characteristics of high efficiency, light weight, smooth operation, impact resistance, low noise, strong overload capacity and long life. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural assembly diagram of a double-support low-backlash cycloid reducer for a small swing-arm robot described in the utility model;

[0019] Figure 2 This is a structural schematic diagram of a double-support low-backlash cycloid reducer for a small swing-arm robot described in the utility model.

[0020] The symbols in the accompanying drawings are described as follows:

[0021] 1. Needle housing; 2. Skeleton oil seal; 3. Needle roller; 4. Rear planetary carrier; 5. Angular contact ball bearing; 6. Rear cycloid pulley; 7. Front cycloid pulley; 8. Front planetary carrier; 9. Circlip for hole; 10. Tapered roller bearing; 11. Needle roller with steel cage; 12. Eccentric shaft gasket; 13. Eccentric shaft; 14. Hexagon socket head screw; 15. Planetary gear gasket; 16. Planetary gear; 17. Sun gear; 18. Input shaft gasket; 19. Input gear shaft. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] See also Figure 1-2 The utility model provides a double-support low-backlash cycloid reducer for a small swing-arm robot, comprising a needle housing 1, a skeleton oil seal 2 being movably clamped on the left side of the interior of the needle housing 1, a rear planetary carrier 4 and a front planetary carrier 8 being respectively provided on the left and right sides of the interior of the needle housing 1, a deflection structure being provided between the rear planetary carrier 4 and the front planetary carrier 8 and the needle housing 1, a hexagon socket head screw 14 being fixed between the rear planetary carrier 4 and the front planetary carrier 8, the rear planetary carrier 4 and the front planetary carrier 8 being fixedly connected by the hexagon socket head screw 14, an input gear shaft 19 being provided on the inner side of the rear planetary carrier 4 and the front planetary carrier 8, and a transmission structure being provided on the surface of the input gear shaft 19;

[0024] The transmission structure includes planetary gear washers 15, planetary gears 16, sun gears 17, and input shaft washers 18. The input shaft washers 18 are movably connected to the left and right ends of the input gear shaft 19. The input shaft washers 18 are located inside the rear planetary carrier 4 and the front planetary carrier 8. The sun gears 17 are mounted on the surface of the input gear shaft 19. There are three groups of planetary gears 16, and the three groups of planetary gears 16 are meshed with the sun gears 17. The planetary gear washers 15 are located on both sides of the planetary gears 16.

[0025] The deflection structure includes a needle roller 3, an angular contact ball bearing 5, a rear cycloid wheel 6, a front cycloid wheel 7, a hole retaining ring 9, a tapered roller bearing 10, a steel cage needle roller 11, an eccentric shaft gasket 12 and an eccentric shaft 13, the planetary gear gasket 15 is movably clamped on the eccentric shaft 13, the planetary gear 16 is mounted on the surface of the eccentric shaft 13, and the planetary gear 16 is fixedly connected to the eccentric shaft 13 through the planetary gear gasket 15. The needle roller 3 is arranged inside the inner wall tooth groove of the needle shell 1, the angular contact ball bearing 5 is movably connected at the port of the needle shell 1, the angular contact ball bearing 5 is located between the needle shell 1 and the rear planetary carrier 4 and the front planetary carrier 8, the steel cage needle roller 11 is arranged inside the end face through hole of the rear cycloid wheel 6 and the front cycloid wheel 7, the rear cycloid wheel 6 and the front cycloid wheel 7 are fixedly connected to the eccentric shaft 13 through the steel cage roller The needle 11 is sleeved on the surface of the eccentric shaft 13, and retaining rings 9 are provided on both sides of the tapered roller bearing 10. The tapered roller bearing 10 is installed on the eccentric shaft 13 through the retaining ring 9. The tapered roller bearing 10 is located between the eccentric shaft 13 and the rear planetary carrier 4 and the front planetary carrier 8. The reducer of this structure has two stages of reduction. The first stage is the planetary mechanism reduction, and the main parts include the input gear shaft 19, the sun gear 17, and the three planetary gears 16. The second stage mainly includes three eccentric shafts 13, two rear cycloid wheels 6 and the front cycloid wheels 7, the rear planetary carrier 4, the front planetary carrier 8, forty needle rollers 3 and the needle shell 1. The two rear cycloid wheels 6 and the front cycloid wheels 7 are differentially meshed with the needle shell 1 to form a reduction. The rear planetary carrier 4 and the front planetary carrier 8 are fixed, and the needle shell 1 outputs.

[0026] Furthermore, the number of teeth of the sun gear 17 is 20, the module is 1.25, the pressure angle is 20°, and the tooth width is 9.3 mm, so that the sun gear 17 can drive the three sets of planetary gears 16 to rotate by engaging with the three sets of planetary gears 16, so that the three sets of planetary gears 16 can drive the eccentric shaft 13 to rotate eccentrically.

[0027] Furthermore, the number of teeth of the planetary gear 16 is 34, the module is 1.25, the pressure angle is 20 degrees, and the tooth width is 6 mm, so that the three groups of planetary gears 16 can drive the eccentric shaft 13 to rotate eccentrically.

[0028] Furthermore, the eccentric distance of the eccentric shaft 13 is 1.1 mm. During the eccentric rotation of the eccentric shaft 13, the steel cage needle roller 11 can stably drive the rear cycloid wheel 6 and the front cycloid wheel 7 to eccentrically swing during the rotation.

[0029] Furthermore, the number of teeth of the rear cycloid wheel 6 and the front cycloid wheel 7 is 39, the outer diameter of the needle gear sleeve is Φ5mm, the eccentricity is 1.1mm, the center circle diameter of the needle wheel is Φ118mm, and the tooth width is 12mm. When the rear cycloid wheel 6 and the front cycloid wheel 7 are deflected, the needle roller 3 and the inner wall tooth grooves of the needle shell 1 are staggered and connected, thereby driving the needle shell 1 to rotate and output.

[0030] Furthermore, the outer diameter of the needle roller 3 is Φ5 mm and the length is 23.8 mm. When the rear cycloid wheel 6 and the front cycloid wheel 7 deflect, the needle roller 3 can be driven to rotate in the tooth groove of the inner wall of the needle housing 1.

[0031] Furthermore, the needle housing 1 has 40 teeth, a center circle diameter of Φ118 mm, and a needle tooth diameter of Φ5 mm. When the needle roller 3 is staggered with the inner wall tooth grooves of the needle housing 1, it can drive the needle housing 1 to rotate and output.

[0032] During use, the rear planetary carrier 4 and the front planetary carrier 8 are first fixedly connected to the external frame, and then the input gear shaft 19 is fixedly connected to the external power source to drive the input gear shaft 19 to rotate, and then the input gear shaft 19 can drive the sun gear 17 to rotate, and the sun gear 17 drives the three sets of planetary gears 16 to rotate by meshing with the three sets of planetary gears 16, so that the three sets of planetary gears 16 can drive the eccentric shaft 13 to rotate eccentrically, and in the process of eccentric rotation of the eccentric shaft 13, the retaining ring 9 can be used to axially limit the tapered roller bearing 10 through the hole, so that the tapered roller bearing 10 can support and rotate the two ends of the eccentric shaft 13, so that the eccentric shaft 13 can more stably drive the steel cage needle roller 11 to rotate, thereby The steel retainer needle roller 11 stably drives the rear cycloid wheel 6 and the front cycloid wheel 7 to eccentrically swing during the rotation process, and when the rear cycloid wheel 6 and the front cycloid wheel 7 deflect, they can drive the needle roller 3 to rotate in the inner wall tooth groove of the needle shell 1, so that the needle roller 3 and the inner wall tooth groove of the needle shell 1 are staggered and connected, thereby driving the needle shell 1 to rotate and output, and the rear cycloid wheel 6 and the front cycloid wheel 7 can also axially limit the rear cycloid wheel 6 and the front cycloid wheel 7 while being slidingly connected with the angular contact ball bearing 5, so that the rear cycloid wheel 6 and the front cycloid wheel 7 can have the characteristics of high efficiency, smooth operation, impact resistance, strong overload capacity and long service life while having a compact structure, so that the rear cycloid wheel 6 and the front cycloid wheel 7 can drive the needle shell 1 to output with a larger torque.

[0033] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A double-support low-backlash cycloid reducer for a small swing-arm robot, comprising a needle housing (1), characterized in that: A skeleton oil seal (2) is movably engaged with the left side of the interior of the needle housing (1); a rear planetary carrier (4) and a front planetary carrier (8) are respectively provided on the left and right sides of the interior of the needle housing (1); a deflection structure for driving the needle housing (1) to output rotation is provided between the rear planetary carrier (4), the front planetary carrier (8) and the needle housing (1); a hexagon socket head screw (14) is fixed between the rear planetary carrier (4) and the front planetary carrier (8); an input gear shaft (19) is provided on the inner side of the rear planetary carrier (4) and the front planetary carrier (8); and a transmission structure for driving the deflection structure to rotate is provided on the surface of the input gear shaft (19).

2. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 1, characterized in that: The transmission structure comprises a planetary gear washer (15), planetary gears (16), sun gears (17) and an input shaft washer (18), wherein the input shaft washer (18) is movably engaged with the left and right ends of the input gear shaft (19), the input shaft washer (18) is located inside the rear planetary carrier (4) and the front planetary carrier (8), the sun gears (17) are mounted on the surface of the input gear shaft (19), the planetary gears (16) are provided in three groups, and the three groups of planetary gears (16) are meshed with the sun gears (17), and the planetary gear washer (15) is provided on both sides of the planetary gears (16).

3. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 2, characterized in that: The deflection structure comprises a needle roller (3), an angular contact ball bearing (5), a rear cycloid wheel (6), a front cycloid wheel (7), a hole retaining ring (9), a tapered roller bearing (10), a steel retaining frame needle roller (11), an eccentric shaft gasket (12) and an eccentric shaft (13), wherein the planetary gear gasket (15) is movably connected to the eccentric shaft (13), the planetary gear (16) is mounted on the surface of the eccentric shaft (13), the planetary gear (16) is fixedly connected to the eccentric shaft (13) through the planetary gear gasket (15), the needle roller (3) is arranged inside the tooth groove of the inner wall of the needle housing (1), and the angular contact ball bearing (5) is movably connected to the port of the needle housing (1).

4. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 3, characterized in that: The angular contact ball bearing (5) is located between the needle housing (1) and the rear planetary carrier (4) and the front planetary carrier (8), and the steel retainer needle roller (11) is arranged inside the end surface through holes of the rear cycloid wheel (6) and the front cycloid wheel (7).

5. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 3, characterized in that: The rear cycloid wheel (6) and the front cycloid wheel (7) are sleeved on the surface of the eccentric shaft (13) through a steel retaining needle roller (11), and hole retaining rings (9) are provided on both sides of the tapered roller bearing (10). The tapered roller bearing (10) is installed on the eccentric shaft (13) through the hole retaining ring (9), and the tapered roller bearing (10) is located between the eccentric shaft (13) and the rear planetary carrier (4) and the front planetary carrier (8).

6. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 2, characterized in that: The number of teeth of the star tooth (17) is 20, the module is 1.25, the pressure angle is 20 degrees, and the tooth width is 9.3 mm.

7. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 2, characterized in that: The planetary gear (16) has 34 teeth, a module of 1.25, a pressure angle of 20°, and a tooth width of 6 mm.

8. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 3, characterized in that: The eccentricity of the eccentric shaft (13) is 1.1 mm.

9. The double-support low-backlash cycloid reducer for a small swing-arm robot according to claim 3, characterized in that: The number of teeth of the rear cycloid wheel (6) and the front cycloid wheel (7) is 39, the outer diameter of the needle tooth sleeve is Φ5mm, the eccentricity is 1.1mm, the diameter of the needle wheel center circle is Φ118mm, and the tooth width is 12mm.

10. The double-support low backlash cycloid reducer for a small swing arm robot according to claim 3, characterized in that: The outer diameter of the needle roller (3) is Φ5 mm and the length is 23.8 mm.

11. The double-support low backlash cycloid reducer for a small swing arm robot according to claim 1, characterized in that: The needle housing (1) has 40 teeth, a center circle diameter of Φ118 mm, and a needle tooth diameter of Φ5 mm.

Images