High-precision human-shaped finger joint structure

Abstract

The invention provides a high-precision human-shaped finger joint structure, and relates to the technical field of human-shaped finger joints, the high-precision human-shaped finger joint structure comprises a first finger section and a second finger section, and a joint rotating structure is arranged between the first finger section and the second finger section; the joint rotating structure comprises a joint rotating shaft arranged in the width direction of the first finger section, harmonic speed reducers coaxial with the joint rotating shaft are installed at the two ends of the joint rotating shaft correspondingly, and the fixed ends and the output ends of the two harmonic speed reducers are connected with the first finger section and the second finger section correspondingly. A motor with the axis arranged in the length direction of the first finger section or the second finger section is installed in the first finger section or the second finger section, an output bevel gear coaxial with the motor is installed at the end, close to the joint rotating shaft, of the motor, an input bevel gear coaxial with the joint rotating shaft and located between the two harmonic speed reducers is further installed on the joint rotating shaft, and the output bevel gear is meshed with the input bevel gear. Input is achieved through the bevel gears, output is achieved through the double-harmonic speed reducers on the two sides of the finger joints, the transmission precision, rigidity and impact resistance of the joints are greatly improved, and the performance requirement for a motor is lowered.

Description

Technical Field

[0001] The invention relates to the technical field of humanoid finger joints, and in particular to a high-precision humanoid finger joint structure. Background Art

[0002] As an end effector, the humanoid finger in the robot plays a vital role in the interaction between the robot and the environment. The humanoid finger needs to have a degree of freedom and load-bearing capacity close to that of a human hand. In conventional humanoid finger joints, the motor is directly connected to the harmonic reducer. The output axes of the motor and the harmonic reducer are perpendicular to the rotation axis of the joint. After the motor drives the harmonic reducer input, the bevel gear installed on the output shaft of the harmonic reducer and the bevel gear installed on the joint rotation axis cooperate with the commutation to achieve the effect of driving the finger joint to rotate and bend.

[0003] During actual use of the above-mentioned humanoid finger joint structure, due to the direct connection between the motor and the harmonic reducer, the motor performance requirements are high in the limited space of the finger; since the output shaft of the harmonic reducer is perpendicular to the rotation axis of the joint, after the finger is subjected to force, the load is borne by the deep groove ball bearings on both sides of the harmonic reducer, and the load capacity is weak; since a set of bevel gear commutation is used as the output, the poor output accuracy of the bevel gear leads to poor output accuracy of the entire finger joint. Summary of the invention

[0004] The purpose of the present invention is to provide a high-precision humanoid finger joint structure, which is input through a bevel gear and output through a dual harmonic reducer on both sides of the finger joint, thereby greatly improving the transmission accuracy, rigidity and impact resistance of the joint and reducing the performance requirements for the motor.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions:

[0006] A high-precision humanoid finger joint structure comprises a finger segment 1 and a finger segment 2, wherein a joint rotation structure is arranged between the finger segment 1 and the finger segment 2; the joint rotation structure comprises a joint rotation shaft arranged along the width direction of the finger segment 1, and harmonic reducers coaxial therewith are installed at both ends of the joint rotation shaft, and the fixed end and output end of the two harmonic reducers are respectively connected to the finger segment 1 and the finger segment 2; a motor with an axis arranged along its length direction is installed in the finger segment 1 or the finger segment 2, and an output bevel gear coaxial therewith is installed at one end of the motor close to the joint rotation shaft, and an input bevel gear coaxial therewith and located between the two harmonic reducers is also installed on the joint rotation shaft, and the output bevel gear meshes with the input bevel gear.

[0007] By adopting the above technical solution, when the motor is working, it drives the output bevel gear to rotate synchronously, and the meshing action of the output bevel gear and the input bevel gear drives the joint rotating shaft to rotate. The joint rotating shaft drives the two harmonic reducers at its two ends to work. Since the fixed end and the output end of the two harmonic reducers are respectively connected to finger segment one and finger segment two, when the harmonic reducer is working, it can drive the finger segment one or finger segment two connected to its output end to rotate, thereby realizing the rotation and bending of the driving finger joint.

[0008] In the present invention, the output bevel gear and the input bevel gear are arranged between the motor and the harmonic reducer, so that the input is from the bevel gear and the output is from two harmonic reducers. Compared with the output of the bevel gear in the prior art, the transmission accuracy of the joint can be greatly improved. The axes of the two harmonic reducers are coaxial with the rotation axis of the joint and perpendicular to the output axis of the motor, which effectively reduces the performance requirements for the motor. At the same time, the two harmonic reducers ensure that the joint has higher rigidity and higher impact resistance. In addition, under the same processing accuracy, the smaller the harmonic reducer, the larger the tooth gap. In the present invention, the two harmonic reducers share the output end, the fixed end and the input shaft (i.e., the rotation axis of the joint), and the phase angle of one of the harmonic reducers can be adjusted to reduce or eliminate the tooth gap, obtain higher accuracy, and further improve the accuracy of the joint.

[0009] Furthermore, one of the two harmonic reducers is a single-rigid-wheel harmonic reducer, and the other is a double-rigid-wheel harmonic reducer.

[0010] By adopting the above technical solution, the tooth clearance of the single-rigid harmonic reducer is small, and the tooth clearance of the double-rigid harmonic reducer is large. When the joint is subjected to small force, the joint accuracy is mainly determined by the single-rigid harmonic reducer, and the joint can obtain low tooth clearance and high precision. The impact resistance of the single-rigid harmonic reducer is small, and the impact resistance of the double-rigid harmonic reducer is large. When the joint is subjected to large force, the double-rigid harmonic reducer jointly bears the impact load, and the single-rigid harmonic reducer is not easily damaged. In addition, the input bevel gear has a downward oblique force on the joint rotation axis, while the single-rigid harmonic reducer has an upward oblique force. The oblique forces in the two opposite directions are neutralized or weakened, which can effectively improve the life and stability of the deep groove ball bearing.

[0011] Furthermore, the single rigid wheel harmonic reducer comprises a rigid wheel 1, a support bearing 1, a flexible wheel 1, a flexible bearing 1 and a wave generator 1, wherein the inner wall of the rigid wheel 1 is provided with a groove matched with the steel ball of the support bearing 1, the rigid wheel 1 serves as the outer ring of the support bearing 1 and is connected to the finger segment 1; the flexible wheel 1 is installed on the side of the inner ring of the support bearing 1 away from the rigid wheel 1, and the flexible wheel is meshed with the inner teeth of the rigid wheel 1, the flexible bearing 1 is arranged between the flexible wheel 1 and the wave generator 1 and corresponds to the position of the inner teeth of the rigid wheel 1, and the flexible bearing 1 is located at one end of the wave generator 1 close to the input bevel gear; a deep groove ball bearing 1 is provided at one end of the wave generator 1 away from the flexible bearing 1, the inner ring of the deep groove ball bearing 1 is installed and connected to the joint rotation shaft, the outer ring of the deep groove ball bearing 1 is provided with a connecting ring 1, and the inner ring of the support bearing 1, the flexible wheel 1 and the connecting ring 1 are all installed on the mounting step on the finger segment 2 that matches it.

[0012] By adopting the above technical solution, the basic structure and working principle of the single rigid wheel harmonic reducer are basically the same as those in the prior art. In the present invention, the rigid wheel 1 is integrated with the support bearing 1 as the outer ring of the support bearing 1. In the limited joint space, the volume of the single rigid wheel harmonic reducer can be appropriately increased, which is not only convenient for the production and manufacturing of various components in the single rigid wheel harmonic reducer, but also can improve the capacity of the single rigid wheel harmonic reducer. Among them, the connecting ring 1 is used to connect the outer ring of the deep groove ball bearing 1 and the inner ring of the support bearing 1. The inner ring of the support bearing 1, the flexible wheel 1 and the connecting ring are all installed on the mounting step matched with the finger segment 2, so as to realize the connection between the single rigid wheel harmonic reducer and the finger segment 2, and facilitate the sequential installation of various components in the joint.

[0013] Furthermore, the double rigid wheel harmonic reducer comprises a rigid wheel 2, a rigid wheel 3, a support bearing 2, a flexible wheel 2, two flexible bearings 2 and a wave generator 2, the inner wall of the rigid wheel 2 and the outer wall of the rigid wheel 3 are respectively provided with grooves matching with the steel balls of the support bearing 2, the rigid wheel 2 serves as the outer ring of the support bearing 2 and is connected to the finger segment 1, and the rigid wheel 3 serves as the inner ring of the support bearing 2; the flexible wheel 2 is meshed with the internal teeth of the rigid wheel 2 and the rigid wheel 3, the two flexible bearings 2 are arranged between the flexible wheel 2 and the wave generator 2 and correspond to the positions of the internal teeth of the rigid wheel 2 and the rigid wheel 3 respectively; a deep groove ball bearing 2 is provided at one end of the wave generator 2 away from the input bevel gear, the inner ring of the deep groove ball bearing 2 is installed and connected to the joint rotation shaft, the outer ring of the deep groove ball bearing 2 is provided with a connecting ring 2, the connecting ring 2 is integrally formed with the finger segment 2, and the rigid wheel 3 is installed on the connecting ring 2.

[0014] By adopting the above technical solution, the basic structure and working principle of the double-rigid-wheel harmonic reducer are basically the same as those in the prior art. In the present invention, the second and third rigid wheels are directly used as the inner and outer rings of the second support bearing, and are integrated with the second support bearing. In the limited joint space, the volume of the double-rigid-wheel harmonic reducer can be appropriately increased, which is not only convenient for the production and manufacturing of various components in the double-rigid-wheel harmonic reducer, but also can improve the capacity of the double-rigid-wheel harmonic reducer. Among them, the connecting ring 2 is used to connect the outer ring of the second deep groove ball bearing and the third rigid wheel, and the third rigid wheel is installed on the connecting ring 2 integrally formed with the second finger segment, so as to realize the connection between the double-rigid-wheel harmonic reducer and the second finger segment, and ensure the connection strength.

[0015] Furthermore, a retaining ring 1 covering the deep groove ball bearing 1 and the connecting ring 1 is provided at one end of the joint rotation axis close to the deep groove ball bearing 1, and the retaining ring 1 and the connecting ring 1 are synchronously installed on the installation step of the finger segment 2.

[0016] By adopting the above technical solution, the retaining ring is used to block the deep groove ball bearing to prevent the deep groove ball bearing from being offset along its axial direction after working for a long time, thereby affecting its working effect. It is also used to seal the single rigid wheel harmonic reducer to prevent foreign matter from entering the single rigid wheel harmonic reducer and affecting its normal operation and service life.

[0017] Furthermore, a second retaining ring covering the second deep groove ball bearing and the second connecting ring is installed at one end of the joint rotation shaft close to the second deep groove ball bearing, and the second retaining ring is installed on the second connecting ring.

[0018] By adopting the above technical scheme, the retaining ring 2 is used to block the deep groove ball bearing 2 to prevent the deep groove ball bearing 2 from being offset along its axial direction after working for a long time, which affects its working effect. It is also used to seal the double rigid wheel harmonic reducer to prevent foreign matter from entering the double rigid wheel harmonic reducer and affecting its normal operation and service life. It cooperates with the retaining ring 1 to achieve sealing at both ends of the joint to ensure stable operation of the joint.

[0019] Furthermore, the support bearing 1 and the support bearing 2 are both four-point contact ball bearings.

[0020] By adopting the above technical solution, both the support bearing 1 and the support bearing 2 use four-point contact ball bearings, which can reduce the starting torque while ensuring their supporting capacity.

[0021] Furthermore, a coaxial planetary drive gear is mounted on the output shaft of the motor, a plurality of planetary wheels meshing with the planetary drive gear are arranged in a circumferential array on the outer circumference of the planetary drive gear, the planetary wheels are mounted on a planet carrier, and the output bevel gear is mounted on an end of the planet carrier away from the planetary wheels.

[0022] By adopting the above technical solution, when the motor is working, it drives the planetary drive gear to rotate synchronously. Under the meshing action of the planetary drive gear and the plurality of planetary wheels, the plurality of planetary wheels rotate while also revolving, driving the planetary carrier to rotate as a whole. The planetary carrier drives the output bevel gear to rotate, and the output bevel gear meshes with the input bevel gear, and the input bevel gear drives the joint rotating shaft to rotate. The meshing of the planetary drive gear and the planetary gear obtains a deceleration effect, and the meshing of the output bevel gear and the input bevel gear also obtains a deceleration effect, that is, there are two-stage deceleration between the motor and the harmonic reducer. When the capacity of the two harmonic reducers increases, the capacity of the motor also needs to increase accordingly, but the capacity of the motor is limited by its volume. When the length and thickness of the finger segment one or the finger segment two are limited, the performance requirements for the motor are reduced by setting a two-stage deceleration between the motor and the harmonic reducer.

[0023] Furthermore, the motor is connected to an encoder coaxial with the motor, and the encoder is installed on a side of the motor away from its output shaft.

[0024] By adopting the above technical solution, an encoder is set to detect the input speed of the motor in real time, thereby improving the input accuracy of the motor. The encoder is directly connected to the motor to improve the detection accuracy.

[0025] Furthermore, an encoder with an axis parallel to the motor output axis is also provided in finger segment one or finger segment two, the encoder and the motor are respectively installed in finger segment one and finger segment two, and an encoding gear meshing with the input bevel gear is installed on the output shaft of the encoder.

[0026] By adopting the above technical solution, when the output bevel gear meshes with the input bevel gear to drive the input bevel gear to rotate, the input bevel gear meshes with the encoding gear at the same time, and the encoder is driven to rotate by the encoding gear, and the encoder is used to detect the input speed in real time, so as to improve the input accuracy. Among them, the encoder and the motor are respectively installed in the finger segment 1 and the finger segment 2, so that the space where the motor is located can be saved for the motor, and a longer motor can be set to improve the performance of the motor.

[0027] In summary, the present invention has the following beneficial effects:

[0028] 1. In the present invention, a motor is arranged along the length direction of the finger segment 1 or the finger segment 2, and a joint rotating shaft is arranged along the width direction of the finger segment 1 or the finger segment 2. The motor output shaft and the joint rotating shaft are driven in reverse by an output bevel gear and an input bevel gear that mesh with each other. Harmonic reducers are respectively installed at both ends of the joint rotating shaft. In this way, the bevel gear input and the two harmonic reducers output can greatly improve the transmission accuracy of the joint, effectively reduce the performance requirements for the motor, and the joint has higher rigidity and higher impact resistance.

[0029] 2. In the present invention, two harmonic reducers with a common output end, a fixed end and an input shaft are provided, and the phase angle of one of the harmonic reducers can be adjusted to reduce or eliminate the backlash, obtain higher precision, and further improve the precision of the joint;

[0030] 3. Among the two harmonic reducers in the present invention, one is a single-rigid-wheel harmonic reducer and the other is a double-rigid-wheel harmonic reducer. The tooth clearance of the single-rigid-wheel harmonic reducer is small, while the tooth clearance of the double-rigid-wheel harmonic reducer is large. When the joint is subjected to small force, the joint accuracy is mainly determined by the single-rigid-wheel harmonic reducer, and the joint can obtain low tooth clearance and high precision; the impact resistance of the single-rigid-wheel harmonic reducer is small, while the impact resistance of the double-rigid-wheel harmonic reducer is large. When the joint is subjected to large force, the double-rigid-wheel harmonic reducer jointly bears the impact load, and the single-rigid-wheel harmonic reducer is not easily damaged; in addition, the input bevel gear has a downward oblique force on the joint rotating shaft, while the single-rigid-wheel harmonic reducer has an upward oblique force, and the oblique forces in two opposite directions are neutralized or weakened, which can effectively improve the life and stability of the deep groove ball bearing;

[0031] 4. In the present invention, the first rigid wheel in the single rigid wheel harmonic reducer is integrated with the outer ring of the first rigid wheel support bearing, and the second rigid wheel and the third rigid wheel in the double rigid wheel harmonic reducer are respectively integrated with the outer ring and the inner ring of the second rigid wheel support bearing, and both the first support bearing and the second support bearing are four-point contact ball bearings, which effectively improves the capacity of the single rigid wheel harmonic reducer and the double rigid wheel harmonic reducer while reducing the starting torque;

[0032] 5. In the present invention, two-stage reduction gears are arranged between the motor and the joint rotating shaft, namely, a planetary drive gear meshing with a planetary gear for reduction, and an output bevel gear meshing with an input bevel gear for reduction. When the length and thickness of the finger segment one or the finger segment two are limited, the performance requirements for the motor are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of a high-precision humanoid finger joint structure in Example 1;

[0034] Figure 2 It is a structural schematic diagram of a high-precision humanoid finger joint structure in Example 2.

[0035] In the figure, 1, finger segment one; 2, finger segment two; 3, joint rotation axis; 31, input bevel gear; 4, single rigid wheel harmonic reducer; 41, rigid wheel one; 42, support bearing one; 43, flexible wheel one; 44, flexible bearing one; 45, wave generator one; 46, deep groove ball bearing one; 47, connecting ring one; 48, retaining ring one; 5, double rigid wheel harmonic reducer; 51, rigid wheel two; 52, rigid wheel three; 53, support bearing two; 54, flexible wheel two; 55, flexible bearing two; 56, wave generator two; 57, deep groove ball bearing two; 58, connecting ring two; 59, retaining ring two; 6, motor; 61, planetary drive gear; 7, planet carrier; 71, planetary gear; 72, output bevel gear; 8, encoder; 81, encoding gear. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0037] Embodiment 1:

[0038] A high-precision humanoid finger joint structure, such as Figure 1 As shown, it includes a finger segment 1 and a finger segment 2, and a joint rotation structure is provided between the finger segment 1 and the finger segment 2, through which the finger segment 1 or the finger segment 2 can be driven to rotate and bend. Specifically, the joint rotation structure includes a joint rotation shaft 3 arranged along the width direction of the finger segment 1, and a harmonic reducer coaxial therewith is installed at both ends of the joint rotation shaft 3, and the fixed end and the output end of the two harmonic reducers are respectively connected to the finger segment 1 and the finger segment 2, and the joint rotation shaft 3 serves as the input shaft of the two harmonic reducers. One of the finger segment 1 and the finger segment 2 is connected to the fixed end of the two harmonic reducers as a fixed end, and the other is connected to the output end of the two harmonic reducers as an output end for rotation and bending.

[0039] like Figure 1 As shown, a motor 6 with its axis arranged along its length direction is installed in finger segment 1 or finger segment 2. In this embodiment, the motor 6 is installed in finger segment 2, and an output bevel gear 72 coaxial with the joint rotation axis 3 is installed at one end of the motor 6 close to the joint rotation axis 3. An input bevel gear 31 coaxial with the joint rotation axis and located between the two harmonic reducers is also installed on the joint rotation axis 3, and the output bevel gear 72 is meshed with the input bevel gear 31.

[0040] like Figure 1As shown, when the motor 6 is working, it drives the output bevel gear 72 to rotate synchronously, and drives the joint rotation shaft 3 to rotate under the meshing action of the output bevel gear 72 and the input bevel gear 31, and the joint rotation shaft 3 drives the two harmonic reducers at its two ends to work. Since the fixed end and the output end of the two harmonic reducers are respectively connected to the finger segment 1 and the finger segment 2 2, when the harmonic reducer is working, it can drive the finger segment 1 or the finger segment 2 2 connected to its output end to rotate, thereby realizing the rotation and bending of the driving finger joint.

[0041] like Figure 1 As shown, the output bevel gear 72 and the input bevel gear 31 are meshed and commutated for input, and two harmonic reducers are output, which can greatly improve the transmission accuracy of the joint compared to the bevel gear output in the prior art. The axes of the two harmonic reducers are coaxial with the joint rotation axis 3 and perpendicular to the output axis of the motor 6, which effectively reduces the performance requirements for the motor 6. At the same time, the two harmonic reducers ensure that the joint has higher rigidity and higher impact resistance. In addition, under the same processing accuracy, the smaller the harmonic reducer, the larger the tooth gap. In the present invention, the two harmonic reducers share the output end, the fixed end and the joint rotation axis 3, and the phase angle of one of the harmonic reducers can be adjusted to reduce or eliminate the tooth gap, obtain higher accuracy, and further improve the accuracy of the joint.

[0042] like Figure 1 As shown, in this embodiment, one of the two harmonic reducers is a single-rigid harmonic reducer 4, and the other is a double-rigid harmonic reducer 5. The single-rigid harmonic reducer 4 has a small tooth gap, and the double-rigid harmonic reducer 5 has a large tooth gap. When the joint is subjected to small forces, the joint accuracy is mainly determined by the single-rigid harmonic reducer 4, and the joint can obtain low tooth gap and high precision. The single-rigid harmonic reducer 4 has a small impact resistance, and the double-rigid harmonic reducer 5 has a large impact resistance. When the joint is subjected to large forces, the double-rigid harmonic reducer 5 jointly bears the impact load, and the single-rigid harmonic reducer 4 is not easily damaged. In addition, the input bevel gear 31 has a downward oblique force component on the joint rotating shaft 3, while the single-rigid harmonic reducer 4 has an upward oblique force component. The two oblique forces in opposite directions are neutralized or weakened, which can effectively improve the life and stability of the deep groove ball bearing.

[0043] Of course, in other embodiments, the two harmonic reducers may both be single-rigid-wheel harmonic reducers 4 or double-rigid-wheel harmonic reducers 5 .

[0044] Specifically, Figure 1As shown, the single rigid wheel harmonic reducer 4 includes a rigid wheel 41, a support bearing 42, a flexible wheel 43, a flexible bearing 44 and a wave generator 45. A groove is provided on the inner wall of the rigid wheel 41 to match the steel ball of the support bearing 42. The rigid wheel 41 serves as the outer ring of the support bearing 42 and is connected to the finger segment 1. The flexible wheel 43 is installed in a top hat shape on the side of the inner ring of the support bearing 42 away from the rigid wheel 41, and the flexible wheel is meshed with the inner teeth of the rigid wheel 41. The flexible bearing 44 is arranged between the flexible wheel 43 and the wave generator 45 and corresponds to the position of the inner teeth of the rigid wheel 41. The flexible bearing 44 is located at one end of the wave generator 45 close to the input bevel gear 31. A deep groove ball bearing 46 is provided at one end of the wave generator 45 away from the flexible bearing 44. The inner ring of the deep groove ball bearing 46 is installed and connected to the joint rotation shaft 3. The outer ring of the deep groove ball bearing 46 is provided with a connecting ring 47. The inner ring of the support bearing 42, the flexible wheel 43 and the connecting ring 47 are all installed on the mounting step on the finger segment 22 that matches it.

[0045] like Figure 1 As shown, the double rigid wheel harmonic reducer 5 includes a rigid wheel 2 51, a rigid wheel 3 52, a support bearing 2 53, a flexible wheel 2 54, two flexible bearings 2 55 and a wave generator 2 56. The inner wall of the rigid wheel 2 51 and the outer wall of the rigid wheel 3 52 are respectively provided with grooves that match the steel balls of the support bearing 2 53. The rigid wheel 2 51 serves as the outer ring of the support bearing 2 53 and is connected to the finger segment 1, and the rigid wheel 3 52 serves as the inner ring of the support bearing 2 53. The flexible wheel 2 54 meshes with the inner teeth of the rigid wheel 2 51 and the rigid wheel 3 52. The two flexible bearings 2 55 are arranged between the flexible wheel 2 54 and the wave generator 2 56 and correspond to the positions of the inner teeth of the rigid wheel 2 51 and the rigid wheel 3 52 respectively. A deep groove ball bearing 57 is provided at one end of the wave generator 56 away from the input bevel gear 31. The inner ring of the deep groove ball bearing 57 is installed and connected to the joint rotation shaft 3. The outer ring of the deep groove ball bearing 57 is provided with a connecting ring 58. The connecting ring 58 is integrally formed with the finger segment 2, and the rigid wheel 3 52 is installed on the connecting ring 58.

[0046] like Figure 1 As shown, the basic structure and working principle of the single-rigid-wheel harmonic reducer 4 and the double-rigid-wheel harmonic reducer 5 are basically the same as those in the prior art, except that the rigid wheel 1 41 is integrated with the support bearing 1 42 as the outer ring of the support bearing 1 42, and the rigid wheel 2 51 and the rigid wheel 3 52 are integrated with the support bearing 2 53 as the inner and outer rings of the support bearing 2 53, which can increase the volume of the single-rigid-wheel harmonic reducer 4 and the double-rigid-wheel harmonic reducer 5 within the limited joint space, and improve their load and impact resistance. Among them, in this embodiment, the support bearing 1 42 and the support bearing 2 53 are both four-point contact ball bearings, which have a smaller starting torque while ensuring their support capacity.

[0047] like Figure 1As shown, a retaining ring 48 covering the deep groove ball bearing 46 and the connecting ring 47 is provided at one end of the joint rotating shaft 3 close to the deep groove ball bearing 46, and the retaining ring 48 and the connecting ring 47 are synchronously installed on the installation step of the finger segment 2 2. A retaining ring 59 covering the deep groove ball bearing 57 and the connecting ring 58 is installed at one end of the joint rotating shaft 3 close to the deep groove ball bearing 57, and the retaining ring 59 is installed on the connecting ring 58. The retaining ring 48 is used to block the deep groove ball bearing 46, and the retaining ring 59 is used to block the deep groove ball bearing 57 to prevent the deep groove ball bearing 46 and the deep groove ball bearing 57 from axial displacement after long-term work. In addition, the retaining ring 48 and the retaining ring 59 also realize sealing from both ends of the joint rotating shaft 3 to prevent foreign matter from entering the single-rigid wheel harmonic reducer 4 and the double-rigid wheel harmonic reducer 5, which affects their service life.

[0048] like Figure 1 As shown, when the capacity of the two harmonic reducers increases, the capacity of the motor 6 also needs to be increased accordingly, but the capacity of the motor 6 is limited by its volume. Therefore, when the length and thickness of the finger segment 1 or the finger segment 2 are limited, a planetary drive gear 61 coaxial with the motor 6 is installed on the output shaft of the motor 6, and a plurality of planetary gears 71 meshing with the planetary drive gear 61 are arranged in a circular array on the outer periphery of the planetary drive gear 61. The planetary gear 71 is installed on the planetary carrier 7 through a fixed axis, and the output bevel gear 72 is installed on the end of the planetary carrier 7 away from the planetary gear 71.

[0049] like Figure 1 As shown, when the motor 6 is working, it drives the planetary drive gear 61 to rotate synchronously. Under the meshing action of the planetary drive gear 61 and the plurality of planetary gears 71, the plurality of planetary gears 71 rotate while also revolving, driving the planetary carrier 7 to rotate as a whole. The planetary carrier 7 drives the output bevel gear 72 to rotate, and the output bevel gear 72 meshes with the input bevel gear 31, and drives the joint rotating shaft 3 to rotate through the input bevel gear 31. The planetary drive gear 61 meshes with the planetary gear 71 to obtain a deceleration effect, and the output bevel gear 72 meshes with the input bevel gear 31 to obtain a deceleration effect. The capacity of the motor 6 multiplied by the reduction ratio must be greater than or equal to the capacity of the two harmonic reducers. Therefore, after setting two-stage reduction between the motor 6 and the harmonic reducer, the performance requirements for the motor 6 can be effectively reduced.

[0050] like Figure 1 As shown, the motor 6 is also connected to an encoder 8 coaxial therewith, and the encoder 8 is installed on the side of the motor 6 away from its output shaft. The encoder 8 is used to detect the input speed of the motor 6 in real time to improve the input accuracy of the motor 6, and the encoder 8 is directly connected to the motor 6 to improve the detection accuracy.

[0051] Embodiment 2:

[0052] A high-precision humanoid finger joint structure, such as Figure 1 and Figure 2As shown, the difference from the first embodiment is that the encoder 8 and the motor 6 are respectively installed in the finger segment 1 and the finger segment 2, so that the space where the motor 6 is located can be saved for the motor 6, and a longer motor 6 can be set to improve the performance of the motor 6. Specifically, in this embodiment, the motor 6 is installed in the finger segment 2, the encoder 8 is installed in the finger segment 1 and the axis is parallel to the axis of the output shaft of the motor 6, and the output shaft of the encoder 8 is installed with an encoding gear 81 that meshes with the input bevel gear 31. When the output bevel gear 72 meshes with the input bevel gear 31 to drive the input bevel gear 31 to rotate, the input bevel gear 31 is simultaneously meshed with the encoding gear 81, and the encoder 8 is driven to rotate through the encoding gear 81, and the encoder 8 is used to detect the input speed in real time, which is convenient for improving the input accuracy.

[0053] The above description shows and describes the preferred embodiments of the present invention. As mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A high-precision humanoid finger joint structure, characterized in that: The invention comprises a finger segment 1 (1) and a finger segment 2 (2), wherein a joint rotation structure is arranged between the finger segment 1 (1) and the finger segment 2 (2); the joint rotation structure comprises a joint rotation shaft (3) arranged along the width direction of the finger segment 1 (1), and a harmonic reducer coaxial with the joint rotation shaft (3) is installed at both ends of the joint rotation shaft (3), and the fixed end and the output end of the two harmonic reducers are respectively connected to the finger segment 1 (1) and the finger segment 2 (2); a motor (6) with an axis arranged along the length direction thereof is installed in the finger segment 1 (1) or the finger segment 2 (2), and an output bevel gear (72) coaxial with the joint rotation shaft (3) is installed at one end of the motor (6) close to the joint rotation shaft (3), and an input bevel gear (31) coaxial with the joint rotation shaft (3) and located between the two harmonic reducers is also installed on the joint rotation shaft (3), and the output bevel gear (72) meshes with the input bevel gear (31).

2. The high-precision humanoid finger joint structure according to claim 1, characterized in that: One of the two harmonic reducers is a single-rigid-wheel harmonic reducer (4), and the other is a double-rigid-wheel harmonic reducer (5).

3. A high-precision humanoid finger joint structure according to claim 2, characterized in that: The single rigid wheel harmonic reducer (4) comprises a rigid wheel (41), a support bearing (42), a flexible wheel (43), a flexible bearing (44) and a wave generator (45). The inner wall of the rigid wheel (41) is provided with a groove matched with the steel ball of the support bearing (42). The rigid wheel (41) serves as the outer ring of the support bearing (42) and is connected to the finger segment (1). The flexible wheel (43) is installed on the side of the inner ring of the support bearing (42) away from the rigid wheel (41), and the flexible wheel is meshed with the inner teeth of the rigid wheel (41). The flexible bearing (44) is arranged between the flexible wheel (43) and the wave generator. The flexible bearing (44) is located between the wave generator (45) and the flexible wheel (41), and corresponds to the inner tooth position of the wave generator (45). The flexible bearing (44) is located at one end of the wave generator (45) close to the input bevel gear (31); the end of the wave generator (45) away from the flexible bearing (44) is provided with a deep groove ball bearing (46), the inner ring of the deep groove ball bearing (46) is installed and connected with the joint rotation shaft (3), and the outer ring of the deep groove ball bearing (46) is provided with a connecting ring (47), and the inner ring of the support bearing (42), the flexible wheel (43) and the connecting ring (47) are all installed on the mounting step on the finger section (2) that matches with it.

4. The high-precision humanoid finger joint structure according to claim 3, characterized in that: The double rigid wheel harmonic reducer (5) comprises a rigid wheel 2 (51), a rigid wheel 3 (52), a support bearing 2 (53), a flexible wheel 2 (54), two flexible bearings 2 (55) and a wave generator 2 (56). The inner wall of the rigid wheel 2 (51) and the outer wall of the rigid wheel 3 (52) are respectively provided with grooves that cooperate with the steel balls of the support bearing 2 (53). The rigid wheel 2 (51) serves as the outer ring of the support bearing 2 (53) and is connected to the finger segment 1 (1). The rigid wheel 3 (52) serves as the inner ring of the support bearing 2 (53). The flexible wheel 2 (54) is connected to the inner teeth of the rigid wheel 2 (51) and the rigid wheel 3 (52). The two flexible bearings (55) are arranged between the flexible wheel (54) and the wave generator (56) and correspond to the inner teeth of the rigid wheel (51) and the rigid wheel (52) respectively; the end of the wave generator (56) away from the input bevel gear (31) is provided with a deep groove ball bearing (57); the inner ring of the deep groove ball bearing (57) is connected to the joint rotation shaft (3); the outer ring of the deep groove ball bearing (57) is provided with a connecting ring (58); the connecting ring (58) is integrally formed with the finger segment (2), and the rigid wheel (52) is installed on the connecting ring (58).

5. The high-precision humanoid finger joint structure according to claim 3, characterized in that: A retaining ring (48) covering the deep groove ball bearing (46) and the connecting ring (47) is provided at one end of the joint rotation shaft (3) close to the deep groove ball bearing (46), and the retaining ring (48) and the connecting ring (47) are synchronously installed on the installation step of the finger section (2).

6. The high-precision humanoid finger joint structure according to claim 4, characterized in that: A second retaining ring (59) covering the second deep groove ball bearing (57) and the second connecting ring (58) is installed at one end of the joint rotating shaft (3) close to the second deep groove ball bearing (57), and the second retaining ring (59) is installed on the second connecting ring (58).

7. The high-precision humanoid finger joint structure according to claim 4, characterized in that: The support bearing 1 (42) and the support bearing 2 (53) are both four-point contact ball bearings.

8. The high-precision humanoid finger joint structure according to claim 1, characterized in that: A planetary drive gear (61) coaxial with the motor (6) is mounted on the output shaft of the motor (6); a plurality of planetary gears (71) meshing with the planetary drive gear (61) are arranged in a circular array on the outer circumference of the planetary drive gear (61); the planetary gears (71) are mounted on a planet carrier (7); and the output bevel gear (72) is mounted on an end of the planet carrier (7) away from the planetary gears (71).

9. A high-precision humanoid finger joint structure according to claim 1 or 8, characterized in that: The motor (6) is connected to an encoder (8) coaxial with the motor (6), and the encoder (8) is installed on a side of the motor (6) away from its output shaft.

10. A high-precision humanoid finger joint structure according to claim 1 or 8, characterized in that: The finger segment 1 (1) or the finger segment 2 (2) is also provided with an encoder (8) whose axis is parallel to the output axis of the motor (6); the encoder (8) and the motor (6) are respectively installed in the finger segment 1 (1) and the finger segment 2 (2); and an encoding gear (81) meshing with the input bevel gear (31) is installed on the output shaft of the encoder (8).

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