Integrated joint and mechanical arm
By integrating a harmonic reducer, servo motor, and torque sensor into the joint of the robotic arm, the problems of low torque detection accuracy and increased size in existing robotic arms are solved. This achieves high-precision torque measurement and a miniaturized joint structure, improving the integration and reliability of the robotic arm.
Patent Information
- Application Number
- CN202422737938.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-08
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-11-08
AI Technical Summary
Existing methods for detecting torque in robotic arms suffer from low measurement accuracy or increased joint size. In particular, when torque sensors are directly installed or torque is indirectly estimated through motor current, the accuracy requirements cannot be met, and the joint load capacity and control difficulty are affected.
Design an integrated joint comprising a harmonic reducer, a servo motor, and a torque sensor. The torque sensor is embedded in the output flange and fixedly connected to the crossed roller bearing. The servo motor drives the harmonic reducer assembly to rotate, and the torque sensor measures and transmits the torque signal to the drive control board to achieve precise torque detection.
Without increasing the axial dimension of the joint, accurate measurement and transmission of torque by the torque sensor were achieved, improving the integration and flexibility of the joint, and enhancing the service life and reliability of the robotic arm.
Smart Images
Figure CN223477672U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of robotics technology, and more specifically, to an integrated joint and robotic arm. Background Technology
[0002] With the development of automation and intelligent technologies in manufacturing, the application of robotic arms in precision manufacturing, healthcare, and service industries is expanding. Among them, the integrated joint, as the core component of the whole machine, plays a crucial role in the accuracy, reliability, and compliance of the machine's operation, as well as the safety of working in collaboration with humans.
[0003] Currently, there are two methods for torque detection in robotic arms. One method is to directly install a torque sensor on the harmonic output flange of the reducer. This approach increases the axial dimension of the joint and its weight, ultimately affecting the joint's load capacity and control difficulty. The other method utilizes the intrinsic relationship between motor drive current and torque, indirectly estimating the joint torque by monitoring and analyzing the motor current signal. However, the relationship between current and torque is affected by various factors such as motor parameters, load characteristics, and temperature, resulting in low measurement accuracy, which fails to meet accuracy requirements in some scenarios. Utility Model Content
[0004] The purpose of this invention is to provide an integrated joint and robotic arm that enables the torque sensor to both transmit and output the torque of the harmonic reducer and detect the magnitude of the torque without increasing the axial dimension of the joint, thereby improving the integration of the joint and the accuracy of torque measurement.
[0005] The embodiments of this utility model are implemented as follows:
[0006] In one aspect, this utility model provides an integrated joint, including a harmonic reducer, a servo motor, and a torque sensor. The servo motor includes a motor body and a drive control board electrically connected to each other, and the torque sensor is electrically connected to the drive control board. The harmonic reducer includes a high-speed shaft and a low-speed shaft arranged concentrically, and also includes a harmonic reduction assembly, an output flange, and a crossed roller bearing arranged coaxially. One side of the torque sensor is embedded in the output flange, and the other side is fixedly connected to the crossed roller bearing. The low-speed shaft passes through the middle of the harmonic reduction assembly, the crossed roller bearing, the torque sensor, and the output flange in sequence. The high-speed shaft is connected to the servo motor, which can drive the high-speed shaft to rotate, thereby driving the harmonic reduction assembly to rotate. The harmonic reduction assembly can transmit the output torque to the joint end or the load end through the torque sensor and the output flange. The torque sensor can measure the output torque and transmit the torque signal to the drive control board, which is used to calculate or control the output torque.
[0007] Optionally, the harmonic deceleration assembly includes a wave generator, a steel wheel, and a flexible wheel. The flexible wheel is sleeved on the outer periphery of the wave generator, and the steel wheel is sleeved on the outer periphery of the flexible wheel. The flexible wheel is located in the middle of the crossed roller bearing. The flexible wheel is fastened to the inner wall of the crossed roller bearing and connected to the torque sensor. After the wave generator rotates and is decelerated by the steel wheel and the flexible wheel, the flexible wheel can transmit the output torque to the torque sensor.
[0008] Optionally, the output flange is fixedly connected to the low-speed shaft, and a first sealing ring is also fitted around the outer periphery of the low-speed shaft. The first sealing ring is located between the low-speed shaft and the torque sensor. The harmonic reducer also includes a bearing pressure plate, which is pressed onto the side of the wave generator facing the torque sensor. A sealed bearing is also provided between the bearing pressure plate and the wave generator. A second sealing ring and a third sealing ring are also fitted around the outer periphery of the low-speed shaft. The second sealing ring and the third sealing ring are located between the inner wall of the low-speed shaft and the sealed bearing.
[0009] Optionally, the harmonic reducer also includes a flexible wheel pressure plate, which passes through the outer periphery of the low-speed shaft and is located on the side of the flexible wheel away from the output flange; the flexible wheel pressure plate, the flexible wheel, and the torque sensor are sequentially fixedly connected by fasteners.
[0010] Optionally, the servo motor includes a housing, a stator, a rotor, and a motor shaft; the stator and rotor are disposed inside the housing, and the rotor is disposed in the middle of the stator; the motor shaft passes through the middle of the rotor, the low-speed shaft is coaxially disposed with the motor shaft and passes through the middle of the motor shaft, and the high-speed shaft part passes into the low-speed shaft.
[0011] Optionally, a first bearing and a second bearing are respectively fitted around the outer periphery of the motor shaft, and the first bearing and the second bearing are located between the motor shaft and the rotor; the servo motor also includes a wave spring and a motor rear cover, the motor rear cover is fixedly connected to the housing, the wave spring is fitted around the outer periphery of the motor shaft and is located between the second bearing and the motor rear cover.
[0012] Optionally, the integrated joint also includes a braking assembly, which includes a brake disc and an electromagnetic brake. The electromagnetic brake is disposed on the outer periphery of the brake disc, and the motor shaft passes through the middle of the brake disc and is fixedly connected to the brake disc.
[0013] Optionally, the integrated joint also includes an encoder assembly, which includes a first encoder section and a second encoder section. The first encoder section includes a high-speed shaft code disk and a high-speed shaft read head. The high-speed shaft code disk is fixedly connected to the motor rear cover via an encoder dust cover. The high-speed shaft read head is disposed on the encoder dust cover and is positioned opposite to the high-speed shaft code disk to achieve high-speed shaft rotational speed measurement. The second encoder section includes a code disk base, a low-speed shaft code disk, and a mounting sleeve, which are fixedly connected in sequence. The side of the mounting sleeve away from the code disk base is rotatably connected to the mounting base via a third bearing. The mounting base is fixedly connected to the motor rear cover, and the mounting sleeve is fitted onto the outer circumference of the low-speed shaft. The second encoder section also includes a low-speed shaft read head, which is disposed on the mounting base and corresponds to the low-speed shaft code disk.
[0014] Optionally, the mounting base is provided with elastic sheet metal on opposite sides along the circumferential direction, and the mounting base is fixedly connected to the motor rear cover through the elastic sheet metal; the outer circumference of the mounting sleeve is provided with a set screw, and the mounting sleeve is fitted onto the outer circumference of the low-speed shaft through the set screw.
[0015] Another aspect of this invention provides a robotic arm comprising one or more integrated joints.
[0016] The beneficial effects of this utility model include at least one of the following:
[0017] This application provides an integrated joint, including a harmonic reducer, a servo motor, and a torque sensor. The servo motor includes a motor body and a drive control board electrically connected to each other, and the torque sensor is electrically connected to the drive control board. The harmonic reducer includes a high-speed shaft and a low-speed shaft arranged concentrically, and also includes a harmonic reduction assembly, an output flange, and a crossed roller bearing arranged coaxially. One side of the torque sensor is embedded in the output flange, and the other side is fixedly connected to the crossed roller bearing. The low-speed shaft passes through the middle of the harmonic reduction assembly, the crossed roller bearing, the torque sensor, and the output flange in sequence. The high-speed shaft is connected to the servo motor, which drives the high-speed shaft to rotate, thereby driving the harmonic reduction assembly to rotate. The harmonic reduction assembly can transmit the output torque to the joint end or the load end via the torque sensor and the output flange. The torque sensor can measure the output torque and transmit the torque signal to the drive control board, which is used to calculate or control the output torque. The aforementioned integrated joint enables the torque sensor to both transmit and output the torque of the harmonic reducer and detect the torque magnitude without increasing the axial dimension of the joint, thus improving the integration, flexibility of use, and accuracy of torque measurement of the joint.
[0018] This application also provides a robotic arm including one or more integrated joints. The robotic arm has a high degree of integration, and the integrated joints have small axial dimensions and weight, thus improving the service life and reliability of the robotic arm. Attached Figure Description
[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 A cross-sectional view of the integrated joint provided in an embodiment of this utility model;
[0021] Figure 2 A top view of the integrated joint provided in an embodiment of this utility model;
[0022] Figure 3 A side view of the integrated joint provided in an embodiment of this utility model;
[0023] Figure 4 An exploded view of the integrated joint provided in an embodiment of this utility model;
[0024] Figure 5 This is a magnified view of the details at point A;
[0025] Figure 6 This is a magnified view of the details at point B;
[0026] Figure 7 This is a magnified view of the details at point C.
[0027] Icons: 100-Integrated joint; 110-Torque sensor; 121-Low speed shaft; 122-Harmonic reducer assembly; 1221-Wave generator; 1222-Flexible wheel; 1223-Steel wheel; 123-Output flange; 1231-Sealing gasket; 124-Crossed roller bearing; 125-First sealing ring; 126-Sealed bearing; 1261-Bearing pressure plate; 127-Second sealing ring; 128-Third sealing ring; 129-Flexible wheel pressure plate; 131-Housing; 132-Stator; 133-Rotor; 134-Motor shaft; 1341-First bearing; 134 2-Second bearing; 1343-Waveform spring; 1344-Motor bearing washer; 135-Motor rear cover; 136-Brake assembly; 1361-Brake disc; 1362-Electromagnetic brake component; 141-High-speed shaft code disk; 142-High-speed shaft read head; 143-Encoder dustproof end cover; 151-Code disk base; 152-Low-speed shaft code disk; 153-Mounting sleeve; 1531-Setting screw; 154-Third bearing; 155-Low-speed shaft read head; 156-Mounting base; 1561-Elastic sheet metal; 157-Cable anti-wear ring; 160-Screw; 170-Driver. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0031] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0032] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0033] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0034] Please refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 In one aspect of this application, an integrated joint 100 is provided, including a harmonic reducer, a servo motor, and a torque sensor 110. The servo motor includes a motor body and a drive control board electrically connected to each other, and the torque sensor 110 is electrically connected to the drive control board. The harmonic reducer includes a high-speed shaft and a low-speed shaft 121 arranged concentrically, and also includes a harmonic reduction assembly 122, an output flange 123, and a crossed roller bearing 124 arranged coaxially. One side of the torque sensor 110 is embedded in the output flange 123, and the other side is fixedly connected to the crossed roller bearing 124. The low-speed shaft 121 is sequentially connected to the middle of the harmonic reduction assembly 122, the crossed roller bearing 124, the torque sensor 110, and the output flange 123. The high-speed shaft is connected to the servo motor, which can drive the high-speed shaft to rotate, thereby driving the harmonic reduction assembly 122 to rotate. The harmonic reduction assembly 122 can transmit the output torque to the joint end or load end through the torque sensor 110 and the output flange 123. The torque sensor 110 can measure the output torque and transmit the torque signal to the drive control board, which is used to calculate or control the output torque.
[0035] Specifically, such as Figure 1 and Figure 4 As shown, this application provides an integrated joint 100, which includes a harmonic reducer. The harmonic reducer includes a high-speed shaft and a low-speed shaft 121 arranged concentrically. The high-speed shaft is the input shaft of the harmonic reducer, which is directly connected to a servo motor. The low-speed shaft 121 is the output shaft of the harmonic reducer, which passes through the middle of the wave generator 1221, the output flange 123 and the crossed roller bearing 124 inside the harmonic reducer in sequence.
[0036] like Figure 5As shown, the harmonic reducer includes a coaxially arranged harmonic reduction assembly 122, an output flange 123, and a crossed roller bearing 124. A low-speed shaft 121 passes sequentially through the middle of the harmonic reduction assembly 122, the crossed roller bearing 124, the torque sensor 110, and the output flange 123. The left and right sides of the torque sensor 110 are fixedly connected to the output flange 123 and the crossed roller bearing 124 respectively via screws 160, thus fixing the torque sensor 110 to the harmonic reducer and forming a closed loop for torque monitoring. To improve the sealing and stability of the connection between the torque sensor 110 and the output flange 123, a sealing gasket 1231 is also provided between the torque sensor 110 and the output flange 123. Since the diameter of the torque sensor 110 is slightly smaller than the diameter of the output flange 123, it can be embedded in the output flange 123. Compared to existing robotic arms that directly install the torque sensor on the output flange, the arrangement method of this application does not increase the axial dimension of the integrated joint 100, thereby increasing the service life and reliability of the integrated joint 100.
[0037] The servo motor drives the harmonic reducer to rotate via the high-speed shaft, which in turn drives the harmonic reduction assembly 122 to rotate. The reduced speed is achieved by the harmonic reduction assembly 122, and then the low-speed rotation is transmitted to the output flange 123 via the crossed roller bearing 124 and torque sensor 110, thus obtaining a lower output speed. Since the torque sensor 110 is located between the output flange 123 and the crossed roller bearing 124, it can transmit and measure the output torque of the harmonic reducer. Simultaneously, the cable of the torque sensor 110 can pass through the hollow low-speed shaft 121 and be electrically connected to the servo motor's drive control board to transmit the torque signal. The drive control board can calculate the output torque based on the torque signal and adjust the output power by controlling the motor itself, thereby achieving precise control of the output torque.
[0038] It should be noted that, in one possible implementation of this application, such as Figure 4 As shown, the harmonic deceleration assembly 122 includes a wave generator 1221, a steel wheel 1223, and a flexible wheel 1222. The flexible wheel 1222 is sleeved on the outer periphery of the wave generator 1221, and the steel wheel 1223 is sleeved on the outer periphery of the flexible wheel 1222. The flexible wheel 1222 is located in the middle of the crossed roller bearing 124. The flexible wheel 1222 is fastened to the inner wall of the crossed roller bearing 124 and connected to the torque sensor 110. After the wave generator 1221 rotates and is decelerated by the steel wheel 1223 and the flexible wheel 1222, the flexible wheel 1222 can transmit the output torque to the torque sensor 110.
[0039] Specifically, the harmonic deceleration assembly 122 includes a wave generator 1221, a steel wheel 1223, and a flexible wheel 1222. The flexible wheel 1222 is sleeved on the outer periphery of the wave generator 1221, and the steel wheel 1223 is sleeved on the outer periphery of the flexible wheel 1222. The flexible wheel 1222 is located in the middle of the crossed roller bearing 124. During the rotation of the wave generator 1221, the flexible wheel 1222 undergoes elastic deformation and interacts with the steel wheel 1223 to achieve the purpose of transmitting power. When the wave generator 1221 is rotated, after deceleration through the flexible wheel 1222 and the steel wheel 1223, the flexible wheel 1222 can transmit torque to the torque sensor 110.
[0040] Furthermore, such as Figure 1 and Figure 4 As shown, in order to improve the connection stability of the harmonic reducer assembly 122, the harmonic reducer also includes a flexible wheel pressure plate 129. The flexible wheel pressure plate 129 passes through the outer periphery of the low-speed shaft 121 and is located on the side of the flexible wheel 1222 away from the output flange 123. The flexible wheel pressure plate 129, the flexible wheel 1222 and the torque sensor 110 are sequentially fixedly connected by fasteners to prevent the flexible wheel 1222 from shifting position during the rotation of the harmonic reducer assembly 122, thereby improving the torque transmission efficiency.
[0041] The aforementioned integrated joint 100 enables the torque sensor 110 to both transmit and output the torque of the harmonic reducer and detect the magnitude of the torque without increasing the axial dimension of the joint, thereby improving the integration, flexibility of use, and accuracy of torque measurement of the joint.
[0042] For example, such as Figure 1 As shown, the output flange 123 is fixedly connected to the low-speed shaft 121. A first sealing ring 125 is also fitted around the outer periphery of the low-speed shaft 121. The first sealing ring 125 is disposed between the low-speed shaft 121 and the torque sensor 110. The harmonic reducer also includes a bearing pressure plate 1261, which is pressed against the side of the wave generator 1221 facing the torque sensor 110. A sealed bearing 126 is also provided between the bearing pressure plate 1261 and the wave generator 1221. A second sealing ring 127 and a third sealing ring 128 are also fitted around the outer periphery of the low-speed shaft 121. The second sealing ring 127 and the third sealing ring 128 are disposed between the inner wall of the low-speed shaft 121 and the sealed bearing 126.
[0043] Specifically, a first sealing ring 125 is sleeved on the outer periphery of the low-speed shaft 121. The first sealing ring 125 is disposed between the low-speed shaft 121 and the torque sensor 110. The rotation of the low-speed shaft 121 and the torque sensor 110 is synchronized. The first sealing ring 125 can prevent the harmonic reduction assembly 122 from leaking oil towards the output flange 123 without affecting the operation of the harmonic reduction assembly 122.
[0044] In the use of existing harmonic reducers, sealing difficulties often arise. Because the wave generator operates at high speed, grease in the reducer easily flows from the wave generator's central hole to the output and motor ends. Since the reducer's interior is sensitive to dust, and the low-speed shaft's runout is often not very precise, commonly used oil seals experience problems such as increased joint resistance, overheating, and grease contamination. If a rigid connection with sealed bearings is used, the non-concentricity of the high and low speed shafts causes the low-speed shaft's runout to disturb the high-speed shaft's movement.
[0045] like Figure 4 As shown, the harmonic reducer of this application also includes a bearing pressure plate 1261, which is pressed onto the side of the wave generator 1221 facing the torque sensor 110. A sealed bearing 126 is also provided between the bearing pressure plate 1261 and the wave generator 1221. The sealing pressure plate can provide a certain limiting and fixing effect on the sealed bearing 126. A second sealing ring 127 and a third sealing ring 128 are also sleeved on the outer periphery of the low-speed shaft 121. The second sealing ring 127 and the third sealing ring 128 are located between the low-speed shaft 121 and the inner wall of the sealed bearing 126. When the servo motor is working at high speed, the sealing bearing 126 and the second sealing ring 127 and the third sealing ring 128 complete the sealing. The second sealing ring 127 and the third sealing ring 128 are in a fine sealing state, which will not cause serious wear to the harmonic reducer, avoid the situation that the internal grease of the reducer will be contaminated after the harmonic reducer is worn, and improve the reliability of the harmonic reducer.
[0046] Meanwhile, since the low-speed shaft 121 passes through the middle of the sealed bearing 126, and the low-speed shaft 121 and the inner wall of the sealed bearing 126 are in a large clearance fit, the deformation of the second sealing ring 127 and the third sealing ring 128 can offset the rotational eccentricity between the wave generator 1221 and the low-speed shaft 121, so as to reduce or avoid the disturbance of the high-speed shaft movement caused by the runout of the low-speed shaft 121 due to the incomplete concentricity between the high-speed shaft and the low-speed shaft 121, thereby improving the reliability of the harmonic reducer.
[0047] For example, such as Figure 1 , Figure 4 and Figure 6 As shown, the servo motor includes a housing 131, a stator 132, a rotor 133, and a motor shaft 134. The stator 132 and the rotor 133 are disposed inside the housing 131, and the rotor 133 is disposed in the middle of the stator 132. The housing 131 can provide a certain degree of protection for the stator 132 and the rotor 133. The motor shaft 134 passes through the middle of the rotor 133. The low-speed shaft 121 is coaxially disposed with the motor shaft 134 and passes through the middle of the motor shaft 134. The high-speed shaft part passes into the low-speed shaft 121 so that the motor shaft 134 can drive the high-speed shaft to rotate.
[0048] Optionally, a first bearing 1341 and a second bearing 1342 are respectively fitted around the outer periphery of the motor shaft 134, and the first bearing 1341 and the second bearing 1342 are disposed between the motor shaft 134 and the rotor 133; the servo motor also includes a wave spring 1343 and a motor rear cover 135, the motor rear cover 135 is fixedly connected to the outer shell 131, the wave spring 1343 is fitted around the outer periphery of the motor shaft 134 and is located between the second bearing 1342 and the motor rear cover 135.
[0049] Specifically, a first bearing 1341 and a second bearing 1342 are respectively fitted around the outer periphery of the motor shaft 134. The first bearing 1341 and the second bearing 1342 are positioned between the motor shaft 134 and the rotor 133. The arrangement of the first bearing 1341 and the second bearing 1342 enables the rotation of the motor shaft 134 and the rotor 133 to be smoother and more reliable. Optionally, a motor bearing washer 1344 can also be provided between the first bearing 1341 and the second bearing 1342 and the motor shaft 134. The servo motor also includes a wave spring 1343, which is fitted around the outer periphery of the motor shaft 134 and located between the second bearing 1342 and the motor rear cover 135. The wave spring 1343 provides the preload required for the second bearing 1342 to ensure the normal operation of the second bearing 1342 and extend its service life.
[0050] In one possible embodiment of this application, the integrated joint 100 further includes a brake assembly 136, which includes a brake disc 1361 and an electromagnetic brake element 1362. The electromagnetic brake element 1362 is disposed on the outer periphery of the brake disc 1361, and the motor shaft 134 passes through the middle of the brake disc 1361 and is fixedly connected to the brake disc 1361.
[0051] Specifically, the brake disc 1361 includes brake pads and a body. The electromagnetic brake disc 1361 can control the contact or separation of the brake pads from the body through electromagnetic force. When current passes through the electromagnet coil, an electromagnetic force is generated to make the brake pads contact the body, thereby achieving the braking function. This allows the robotic arm to stop stably at the required stopping position, preventing unnecessary injury or damage due to weight imbalance or other reasons. When the current is disconnected, the electromagnetic force disappears, the brake pads separate from the body, and the robotic arm can then operate. The brake assembly 136 ensures the safety of the joints and the robotic arm, preventing damage caused by accidental loss of control of the joints and the robotic arm.
[0052] In one possible implementation of this application, such as Figure 4 and Figure 7As shown, the integrated joint 100 also includes an encoder assembly, which includes a first encoder section and a second encoder section. The first encoder section includes a high-speed shaft code disk 141 and a high-speed shaft read head 142. The high-speed shaft code disk 141 is fixedly connected to the motor rear cover 135 through an encoder dustproof end cover 143. The high-speed shaft read head 142 is disposed on the encoder dustproof end cover 143 and is disposed opposite to the high-speed shaft code disk 141 to realize the speed measurement of the high-speed shaft. The second encoder section includes a code disk base 151, a low-speed shaft code disk 152, and a mounting sleeve 153, which are fixedly connected in sequence. The side of the mounting sleeve 153 away from the code disk base 151 is rotatably connected to the mounting base 156 through a third bearing 154. The mounting base 156 is fixedly connected to the motor rear cover 135. The mounting sleeve 153 is sleeved on the outer periphery of the low-speed shaft 121. The second encoder section also includes a low-speed shaft read head 155, which is disposed on the mounting base 156 and corresponds to the low-speed shaft code disk 152.
[0053] Specifically, if Figure 4 and Figure 7 As shown, the integrated joint 100 also includes an encoder assembly, which includes a first encoder section and a second encoder section. The first encoder section is used to realize the speed measurement of the high-speed shaft, and the second encoder section is used to realize the speed measurement of the low-speed shaft 121. The first encoder section and the second encoder section are electrically connected to the driver 170 respectively.
[0054] The first encoding unit includes a high-speed shaft code disk 141 and a high-speed shaft reading head 142. The high-speed shaft code disk 141 is fixedly connected to the motor rear cover 135 through the encoder dustproof end cover 143. The high-speed shaft reading head 142 is disposed on the encoder dustproof end cover 143 and is disposed opposite to the high-speed shaft code disk 141. Since the servo motor is directly connected to the high-speed shaft, when the servo motor rotates, it can drive the high-speed shaft and the motor rear cover 135 to rotate synchronously, so that the high-speed shaft reading head 142 reads the rotation speed of the high-speed shaft code disk 141 on the encoder dustproof end cover 143 of the motor rear cover 135, thereby realizing the rotation speed measurement of the high-speed shaft.
[0055] The second encoding unit includes a code disk base 151, a low-speed shaft code disk 152, and a mounting sleeve 153, which are fixedly connected in sequence. The side of the mounting sleeve 153 away from the code disk base 151 is rotatably connected to the mounting base 156 via a third bearing 154. The mounting base 156 makes the connection of the mounting sleeve 153 more stable. The mounting base 156 is fixedly connected to the motor rear cover 135. The mounting sleeve 153 is sleeved on the outer circumference of the low-speed shaft 121 so as to rotate synchronously with the low-speed shaft 121. The second encoding unit also includes a low-speed shaft reading head 155, which is disposed on the mounting base 156 and corresponds to the low-speed shaft code disk 152. When the low-speed shaft 121 rotates, it can drive the low-speed shaft code disk 152 to rotate synchronously through the mounting sleeve 153, so that the low-speed shaft reading head 155 reads the rotation speed of the low-speed shaft code disk 152, thereby realizing the rotation speed measurement of the low-speed shaft 121.
[0056] It should be noted that, firstly, a cable anti-wear ring 157 is also provided on the side of the encoder base 151 away from the high-speed axis encoder 141 to prevent cable wear when the cable is laid in the middle of the servo motor, thereby improving the reliability of the integrated joint 100.
[0057] Second, in order to further reduce the axial dimension of the integrated joint 100, preferably, the high-speed shaft code disk 141 of the first encoding part and the low-speed shaft code disk 152 of the second encoding part can be coaxially arranged and located on the same horizontal plane, so that the components of the first encoding part and the components of the second encoding part share space in the circumferential direction, thereby reducing the axial dimension of the integrated joint 100.
[0058] Preferably, the mounting base 156 is provided with elastic sheet metal 1561 on opposite sides along the axial direction, and the mounting base 156 is fixedly connected to the motor rear cover 135 through the elastic sheet metal 1561; the mounting sleeve 153 is provided with a set screw 1531 on the outer periphery, and the mounting sleeve 153 is fitted on the outer periphery of the low speed shaft 121 through the set screw 1531. The setting of the set screw 1531 can improve the installation stability of the mounting sleeve 153.
[0059] Specifically, if Figure 7 As shown, the mounting base 156 has elastic sheet metal 1561 on opposite sides along the axial direction. Since the elastic sheet metal 1561 has high stiffness in the circumferential direction and low stiffness in the radial direction, it can absorb the radial runout of the low-speed shaft 121. The high stiffness in the circumferential direction can ensure that the speed monitoring accuracy of the low-speed shaft 121 is not affected.
[0060] In another aspect of this application, a robotic arm is provided, including one or more integrated joints 100.
[0061] Specifically, another aspect of this application provides a robotic arm comprising at least one arm body, wherein when multiple arm bodies are included, any two adjacent arm bodies are movably connected via an integrated joint 100. The specific structure and beneficial effects of the integrated joint 100 have been described in detail above and will not be repeated here. The aforementioned robotic arm exhibits high integration, while the axial dimension and weight of the integrated joint 100 are relatively small, thus improving the service life and reliability of the robotic arm.
[0062] The above description is merely an optional embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
[0063] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, this utility model will not describe the various possible combinations separately.
Claims
1. An integrated joint, characterized in that, The system includes a harmonic reducer, a servo motor, and a torque sensor (110). The servo motor includes a motor body and a drive control board that are electrically connected, and the torque sensor (110) is electrically connected to the drive control board. The harmonic reducer includes a high-speed shaft and a low-speed shaft (121) arranged concentrically, and also includes a harmonic reduction assembly (122), an output flange (123), and a crossed roller bearing (124) arranged coaxially. One side of the torque sensor (110) is embedded in the output flange (123), and the other side is fixedly connected to the crossed roller bearing (124). The low-speed shaft (121) passes through the harmonic reduction assembly in sequence. (122), the middle part of the crossed roller bearing (124), the torque sensor (110) and the output flange (123); the high-speed shaft is connected to the servo motor, the servo motor can drive the high-speed shaft to rotate, and then drive the harmonic deceleration assembly (122) to rotate, the harmonic deceleration assembly (122) can transmit the output torque to the joint end or load end through the torque sensor (110) and the output flange (123), the torque sensor (110) can measure the output torque and transmit the torque signal to the drive control board, the drive control board is used to calculate or control the output torque.
2. The integrated joint according to claim 1, characterized in that, The harmonic deceleration assembly (122) includes a wave generator (1221), a steel wheel (1223), and a flexible wheel (1222). The flexible wheel (1222) is sleeved on the outer periphery of the wave generator (1221), and the steel wheel (1223) is sleeved on the outer periphery of the flexible wheel (1222). The flexible wheel (1222) is located in the middle of the crossed roller bearing (124). The flexible wheel (1222) is fastened to the inner wall of the crossed roller bearing (124) and connected to the torque sensor (110). After the wave generator (1221) rotates and is decelerated by the steel wheel (1223) and the flexible wheel (1222), the flexible wheel (1222) can transmit the output torque to the torque sensor (110).
3. The integrated joint according to claim 2, characterized in that, The output flange (123) is fixedly connected to the low-speed shaft (121). A first sealing ring (125) is also sleeved on the outer periphery of the low-speed shaft (121). The first sealing ring (125) is disposed between the low-speed shaft (121) and the torque sensor (110). The harmonic reducer also includes a bearing pressure plate (1261). The bearing pressure plate (1261) is pressed on the side of the wave generator (1221) facing the torque sensor (110). A sealed bearing (126) is also provided between the bearing pressure plate (1261) and the wave generator (1221). A second sealing ring (127) and a third sealing ring (128) are also sleeved on the outer periphery of the low-speed shaft (121). The second sealing ring (127) and the third sealing ring (128) are disposed between the inner wall of the low-speed shaft (121) and the sealed bearing (126).
4. The integrated joint according to claim 3, characterized in that, The harmonic reducer also includes a flexible wheel pressure plate (129), which passes through the outer periphery of the low-speed shaft (121) and is located on the side of the flexible wheel (1222) away from the output flange (123); the flexible wheel pressure plate (129), the flexible wheel (1222) and the torque sensor (110) are sequentially fixedly connected by fasteners.
5. The integrated joint according to claim 1, characterized in that, The servo motor includes a housing (131), a stator (132), a rotor (133), and a motor shaft (134); the stator (132) and the rotor (133) are disposed inside the housing (131), and the rotor (133) is disposed in the middle of the stator (132); the motor shaft (134) passes through the middle of the rotor (133), the low-speed shaft (121) is coaxially disposed with the motor shaft (134) and passes through the middle of the motor shaft (134), and the high-speed shaft part passes into the low-speed shaft (121).
6. The integrated joint according to claim 5, characterized in that, The outer periphery of the motor shaft (134) is also fitted with a first bearing (1341) and a second bearing (1342), which are disposed between the motor shaft (134) and the rotor (133). The servo motor also includes a wave spring (1343) and a motor rear cover (135). The motor rear cover (135) is fixedly connected to the outer shell (131). The wave spring (1343) is fitted on the outer periphery of the motor shaft (134) and is located between the second bearing (1342) and the motor rear cover (135).
7. The integrated joint according to claim 6, characterized in that, The integrated joint (100) also includes a brake assembly (136), which includes a brake disc (1361) and an electromagnetic brake element (1362). The electromagnetic brake element (1362) is disposed on the outer periphery of the brake disc (1361), and the motor shaft (134) passes through the middle of the brake disc (1361) and is fixedly connected to the brake disc (1361).
8. The integrated joint according to claim 7, characterized in that, The integrated joint (100) also includes an encoder assembly, which includes a first encoder section and a second encoder section. The first encoder section includes a high-speed shaft code disk (141) and a high-speed shaft reader (142). The high-speed shaft code disk (141) is fixedly connected to the motor rear cover (135) via an encoder dust cover (143). The high-speed shaft reader (142) is disposed on the encoder dust cover (143) and is opposite to the high-speed shaft code disk (141) to realize the speed measurement of the high-speed shaft. The second encoder section includes a code disk base (141) fixedly connected in sequence. 151), low-speed shaft code disk (152), mounting sleeve (153), the side of the mounting sleeve (153) away from the code disk base (151) is rotatably connected to the mounting base (156) through a third bearing (154), the mounting base (156) is fixedly connected to the motor rear cover (135), and the mounting sleeve (153) is sleeved on the outer periphery of the low-speed shaft (121); the second encoding part also includes a low-speed shaft reading head (155), the low-speed shaft reading head (155) is disposed on the mounting base (156) and corresponds to the low-speed shaft code disk (152).
9. The integrated joint according to claim 8, characterized in that, The mounting base (156) has elastic sheet metal (1561) on opposite sides along the circumferential direction. The mounting base (156) is fixedly connected to the motor rear cover (135) through the elastic sheet metal (1561). The mounting sleeve (153) is fitted with a set screw (1531) on its outer periphery. The mounting sleeve (153) is fitted onto the outer periphery of the low-speed shaft (121) through the set screw (1531).
10. A robotic arm, characterized in that, It includes one or more integrated joints (100) as described in any one of claims 1-9 above.