Rotary joint and surgical robot

Abstract

The invention provides a rotary joint and a surgical robot, the surgical robot comprises the rotary joint, and the rotary joint comprises a driving part used for outputting rotary motion; the driving wheel is connected with the output end of the driving part; the output wheel is in meshing transmission with the driving wheel; the driven wheel is in meshing transmission with the output wheel; the damping structure is connected with the driven wheel and used for providing preset rotation resistance for the driven wheel; the first brake is used for braking the driving wheel; the second brake is used for braking the driven wheel. When the driving part drives the driving wheel to rotate, due to the fact that the damping structure has the preset rotation resistance to the driven wheel, the tooth surface of the driven wheel is attached to the tooth surface of the output wheel all the time, and therefore the back clearance between gear transmission can be eliminated, the transmission precision is improved, and the surgical risk is reduced. The driving wheel and the driven wheel are braked through the first brake and the second brake respectively, the tooth faces on the two sides of the output wheel can be effectively braked, the braking effectiveness of the output wheel is improved, and shaking in the braking process is avoided.

Description

Technical Field

[0001] The present application belongs to the field of medical device technology, and more specifically, relates to a rotary joint and a surgical robot. Background Art

[0002] With advances in science and technology, surgical robots assisting surgeons in minimally invasive laparoscopic surgery has become a growing trend. The surgeon manipulates the robot through certain surgical movements, and the robot's internal control mechanisms and sensors respond promptly, enabling the robot's end effector to replicate the surgeon's hand movements, enabling the robot to perform procedures such as cutting, hemostasis, and suturing diseased tissue.

[0003] In order to drive the end effector to complete various actions, the surgical robot includes multiple rotary joints. The rotary joints generally output rotation through gear transmission. However, due to errors in design and processing, the gear transmission mechanism is prone to rotational backlash or hysteresis, which affects the transmission accuracy of the rotary joint and brings risks to the surgery. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a rotary joint and a surgical robot to solve the technical problem in the prior art that backlash easily occurs in the gear transmission mechanism, resulting in low transmission accuracy of the rotary joint.

[0005] To achieve the above objectives, the technical solution adopted in this application is: providing a rotary joint, comprising:

[0006] A driving member for outputting rotational motion;

[0007] a driving wheel connected to the output end of the driving member;

[0008] An output wheel meshing with the driving wheel for transmission;

[0009] A driven wheel meshing with the output wheel for transmission;

[0010] a damping structure connected to the passive wheel and used to provide a preset rotational resistance for the passive wheel;

[0011] a first brake, for braking the driving wheel;

[0012] The second brake is used to brake the passive wheel.

[0013] In one embodiment, the pitch circle diameter of the driving wheel is smaller than the pitch circle diameter of the output wheel;

[0014] And / or, the pitch circle diameter of the driven wheel is smaller than the pitch circle diameter of the output wheel.

[0015] In one embodiment, the pitch circle diameter of the driving wheel is equal to the pitch circle diameter of the driven wheel;

[0016] Alternatively, the pitch circle diameter of the driving wheel is not equal to the pitch circle diameter of the driven wheel.

[0017] In one embodiment, the first brake is a permanent magnet brake;

[0018] And / or, the second brake is a permanent magnet brake.

[0019] In one embodiment, the rotary joint further includes a controller, the first brake, the second brake and the driving member are electrically connected to the controller respectively, and the controller controls the first brake and the second brake to work synchronously.

[0020] In one embodiment, the damping structure is used to provide a friction load to the passive wheel;

[0021] Alternatively, the damping structure is used to directly provide a torque load to the passive wheel.

[0022] In one embodiment, the damping member is a friction plate abutting against one axial end of the driven wheel;

[0023] Alternatively, the damping member is a friction plate that hugs the circumference of the passive wheel;

[0024] Alternatively, the damping member is a torsion spring connected to the passive wheel.

[0025] In one embodiment, the rotary joint further comprises:

[0026] case;

[0027] A driving shaft is rotatably mounted on the housing, the driving wheel is fixedly sleeved on the driving shaft, and the first brake is connected to the driving shaft; and / or,

[0028] An output shaft is rotatably mounted on the housing, and the output wheel is fixedly sleeved on the output shaft; and / or,

[0029] The passive shaft is rotatably mounted on the housing, the passive wheel is fixedly sleeved on the passive shaft, the second brake is connected to the passive shaft, and the damping structure is connected to the passive shaft.

[0030] In one embodiment, the damping structure includes a steel ball, an elastic member and a locking member. The steel ball abuts against one axial end of the passive shaft, the elastic member abuts between the steel ball and the locking member, and the locking member is threadedly mounted on the shell.

[0031] On the other hand, the present application also provides a surgical robot comprising the above-mentioned rotary joint.

[0032] The beneficial effects of the rotary joint and surgical robot provided by the present application are as follows: by adding a passive wheel that meshes with the output wheel on the basis of the active wheel and the output wheel, and the passive wheel is connected to a damping structure, and the damping structure provides a preset rotational resistance for the passive wheel, so that when the driving member drives the active wheel to rotate, the active wheel drives the output wheel to rotate, and the output wheel drives the passive wheel to rotate. Because the damping structure has a preset rotational resistance on the passive wheel, the tooth surface of the passive wheel and the tooth surface of the output wheel are always in contact, thereby eliminating the backlash between the gear transmission, improving transmission accuracy, and reducing surgical risks. In addition, the first brake and the second brake are used to brake the active wheel and the passive wheel respectively, so that the tooth surfaces on both sides of the output wheel can be effectively braked, thereby improving the braking effectiveness of the output wheel and avoiding shaking during the braking process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0034] Figure 1 A schematic diagram of the three-dimensional structure of a surgical robot provided in an embodiment of the present application;

[0035] Figure 2 A schematic diagram of the top view of the rotary joint provided in an embodiment of the present application;

[0036] Figure 3 for Figure 2 AA cross-sectional structure diagram of the mid-rotation joint;

[0037] Figure 4 for Figure 2 BB cross-sectional structure diagram of the mid-rotation joint;

[0038] Figure 5 A schematic diagram of the structure behind the rotary joint driving housing provided in an embodiment of the present application;

[0039] Figure 6 A transmission diagram of the driving wheel, output wheel, and driven wheel in the rotary joint provided in an embodiment of the present application when the driving wheel rotates counterclockwise;

[0040] Figure 7 This is a transmission diagram of the driving wheel, output wheel and driven wheel in the rotary joint provided in an embodiment of the present application when the driving wheel rotates clockwise.

[0041] Among them, the reference numerals in the figures are:

[0042] 1. Rotary joint; 100. Driving member; 200. Active pulley; 210. First tooth; 211. First left tooth surface; 212. First right tooth surface; 300. Output pulley; 310. Second tooth; 311. Second left tooth surface; 312. Second right tooth surface; 400. Driven pulley; 410. Third tooth; 411. Third left tooth surface; 412. Third right tooth surface; 500. First brake; 600. Second brake; 700. Damping structure; 710. Steel ball; 720, elastic part; 730, locking part; 800, shell; 810, base; 811, bottom plate; 812, side plate; 8121, step; 813, mounting cavity; 820, cover plate; 900, driving shaft; 910, first limit plate; 1000, output shaft; 1100, driven shaft; 1110, second limit plate; 1200, first bearing; 1300, second bearing; 1400, third bearing; 1500, mounting plate; 2, moving joint. DETAILED DESCRIPTION

[0043] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0044] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0045] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0047] Laparoscopic minimally invasive surgery is increasingly popular among doctors and patients due to its advantages, including small incisions, minimal pain, rapid recovery, minimal bleeding, and shortened hospital stays. With advances in science and technology, robotic surgery to assist surgeons in performing minimally invasive laparoscopic surgery has become a growing trend. The surgeon manipulates the robot through specific surgical movements, and the robot's internal control mechanisms and sensors respond promptly, enabling the robot's end effector to replicate the surgeon's hand movements, enabling incision, hemostasis, and suturing of diseased tissue.

[0048] In order to drive the end effector to complete various actions, the surgical robot includes multiple rotary joints. The rotary joints generally output rotation through gear transmission. However, due to errors in design and processing, the gear transmission mechanism is prone to rotational backlash or hysteresis, which affects the transmission accuracy of the rotary joint and brings risks to the surgery.

[0049] In order to solve the above problems, the embodiments of the present application provide a rotary joint and a surgical robot. On the basis of the active wheel and the output wheel, a passive wheel that meshes with the output wheel for transmission is added, and the passive wheel is connected to a damping structure. The damping structure provides a preset rotational resistance for the passive wheel, so that when the driving member drives the active wheel to rotate, the active wheel drives the output wheel to rotate, and the output wheel drives the passive wheel to rotate. Because the damping structure has a preset rotational resistance for the passive wheel, the tooth surface of the passive wheel and the tooth surface of the output wheel are always in contact, thereby eliminating the backlash between the gear transmission, improving transmission accuracy, and reducing surgical risks. In addition, the first brake and the second brake are used to brake the active wheel and the passive wheel respectively, so that the tooth surfaces on both sides of the output wheel can be effectively braked, thereby improving the braking effectiveness of the output wheel and avoiding shaking during the braking process.

[0050] See also Figure 1 , the surgical robot provided in an embodiment of the present application is now described. The surgical robot includes at least one rotary joint 1, which is used to complete rotation transmission.

[0051] Among them, the number of rotary joints 1 can be determined according to the action that the end effector of the surgical robot needs to perform. The rotary joints 1 can be one, two, three or more. In addition, the movable joints 2 can be interspersed on the basis of the rotary joints 1. The movable joints 2 are used to realize moving actions, such as driving the end effector to move horizontally, vertically or tilted.

[0052] Please also refer to Figures 2 to 5The rotary joint 1 provided in an embodiment of the present application is now described. The rotary joint 1 is primarily used in a surgical robot to achieve rotational drive of an end effector. It is understood that in other embodiments of the present application, the rotary joint 1 may also be used in other products requiring joints, such as walking robots and processing robots, and this is not intended to be a sole limitation.

[0053] The rotary joint 1 includes a driving member 100, a driving wheel 200, an output wheel 300, a driven wheel 400, a first brake 500, a second brake 600, and a damping structure 700. The driving member 100 is used to output rotational motion; the driving wheel 200 is connected to the output end of the driving member 100; the output wheel 300 meshes with the driving wheel 200 for transmission; the driven wheel 400 meshes with the output wheel 300 for transmission; the damping structure 700 is connected to the driven wheel 400 and is used to provide a predetermined rotational resistance for the driven wheel 400; the first brake 500 is used to brake the driving wheel 200; and the second brake 600 is used to brake the driven wheel 400.

[0054] The driving wheel 200 is meshed with the output wheel 300 for transmission, and the output wheel 300 is meshed with the driven wheel 400 for transmission, that is, the driving wheel 200, the output wheel 300 and the driven wheel 400 are all gears. Figure 6 and Figure 7 For ease of description, the teeth of the driving wheel 200, the teeth of the output wheel 300, and the teeth of the driven wheel 400 are named first teeth 210, second teeth 310, and third teeth 410, respectively. Furthermore, each tooth has two opposing tooth flanks. For ease of description, the counterclockwise tooth flank of the first tooth 210 is designated as the first left tooth flank 211, and the clockwise tooth flank of the first tooth 210 is designated as the first right tooth flank 212; the counterclockwise tooth flank of the second tooth 310 is designated as the second left tooth flank 311, and the clockwise tooth flank of the second tooth 310 is designated as the second right tooth flank 312; the counterclockwise tooth flank of the third tooth 410 is designated as the third left tooth flank 411, and the clockwise tooth flank of the third tooth 410 is designated as the third right tooth flank 412. In addition, the driving wheel 200 and the output wheel 300 are externally meshed, and the output wheel 300 and the driven wheel 400 are also externally meshed. The first teeth 210, the second teeth 310 and the third teeth 410 are all formed on the outside of the driving wheel 200, the output wheel 300 and the driven wheel 400.

[0055] The damping structure 700 is used to provide a preset rotational resistance for the passive wheel 400, which is greater than the starting torque of the driving member 100 and is less than the rotational driving force of the driving wheel 200. When the rotation of the output wheel 300 drives the passive wheel 400 to rotate, the damping structure 700 will block the rotation of the passive wheel 400, causing the rotation of the passive wheel 400 to lag. However, since the rotational driving force of the driving wheel 200 is greater than the preset rotational resistance of the damping structure 700, the tooth surface of the output wheel 300 will eventually fit tightly against the tooth surface of the passive wheel 400, and the passive wheel 400 can be driven to rotate by the output wheel 300, thereby eliminating the rotational backlash between the driving wheel 200 and the output wheel 300. Similarly, when the driving wheel 200 changes direction, the driving wheel 200 drives the output wheel 300 to rotate, and the output wheel 300 drives the driven wheel 400 to rotate. The damping structure 700 also provides a preset rotational resistance to the driven wheel 400 to ensure that the tooth surfaces of the output wheel 300 and the tooth surfaces of the driven wheel 400 are in close contact. Generally speaking, regardless of the direction in which the driven wheel 400 tends to rotate, the damping structure 700 will prevent the rotation of the driven wheel 400 to ensure that the tooth surfaces of the output wheel 300 and the tooth surfaces of the driven wheel 400 are in close contact, thereby eliminating gear transmission backlash.

[0056] Specifically, such as Figure 6 As shown, when the driving member 100 outputs counterclockwise rotation, the driving member 100 drives the driving wheel 200 to rotate counterclockwise, and the first left tooth surface 211 of the driving wheel 200 contacts the second right tooth surface 312 of the output wheel 300, thereby driving the output wheel 300 to rotate clockwise. At the same time, due to the resistance of the damping structure 700, the second left tooth surface 311 of the output wheel 300 finally contacts the third right tooth surface 412 of the driven wheel 400, thereby driving the driven wheel 400 to rotate counterclockwise. When the driving member 100 outputs a clockwise rotational motion, the driving member 100 drives the driving wheel 200 to rotate clockwise, and the first right tooth surface 212 of the driving wheel 200 contacts the second left tooth surface 311 of the output wheel 300, thereby driving the output wheel 300 to rotate counterclockwise. At the same time, due to the resistance of the damping structure 700, the second right tooth surface 312 of the output wheel 300 finally contacts the third left tooth surface 411 of the driven wheel 400, thereby driving the driven wheel 400 to rotate clockwise.

[0057] The above arrangement ensures that no matter whether the driving wheel 200 rotates clockwise or counterclockwise, the second left tooth surface 311 and the second right tooth surface 312 of the output wheel 300 can fit with the corresponding tooth surfaces, that is, the output wheel 300 is in a left-right clamped state, eliminating the backlash of the output wheel 300 due to design and manufacturing errors during the transmission process, improving the transmission accuracy of the gear transmission, and improving the movement accuracy of the rotary joint 1.

[0058] In addition, by providing the first brake 500 and the second brake 600 on the driving wheel 200 and the driven wheel 400, respectively, when the output wheel 300 needs to be stopped in a certain state, the driving wheel 200 and the driven wheel 400 can be locked respectively by the first brake 500 and the second brake 600, and the second left tooth surface 311 and the second right tooth surface 312 of the output wheel 300 are continuously in contact with the driving wheel 200 and the driven wheel 400, respectively, thereby ensuring that the output wheel 300 can be locked at any time in any direction, achieving a backlash-free output. At this time, if the output wheel 300 continues to rotate in the original direction of rotation due to inertia, it will be braked due to the contact of the tooth surface of the driven wheel 400. On the contrary, if it rotates in the opposite direction, it will be braked due to the contact of the tooth surface of the driving wheel 200, thereby achieving a locking effect, avoiding shaking during the braking process, and improving the control effect.

[0059] In one embodiment, see Figure 6 The pitch circle diameter of the driving wheel 200 is smaller than the pitch circle diameter of the output wheel 300, that is, the transmission ratio between the driving wheel 200 and the output wheel 300 is greater than 1. The small torque locking of the driving wheel 200 by the first brake 500 can achieve a large torque locking of the output wheel 300, thereby achieving joint brake locking. In other words, when it is necessary to provide the same magnitude of torque locking to the output wheel 300, it is only necessary to use the relatively small first brake 500 to lock the driving wheel 200 to achieve locking of the output wheel 300, thereby reducing the size and occupied space of the first brake 500, which is conducive to reducing the size of the rotary joint or other electromechanical systems. In addition, because the transmission ratio between the driving wheel 200 and the output wheel 300 is greater than 1, the driving member 100 only needs to provide a smaller torque to drive the output shaft 1000, thereby also reducing the size and occupied space of the driving member 100.

[0060] Specifically, the transmission ratio between the driving wheel 200 and the output wheel 300 can be set according to actual needs. For example, the transmission ratio can be set to 1.5, 2, 2.5 or 3.

[0061] In one embodiment, see Figure 6 The pitch circle diameter of the driven wheel 400 is smaller than that of the output wheel 300, meaning that the transmission ratio between the driven wheel 400 and the output wheel 300 is greater than 1. The low-torque locking of the driven wheel 400 by the second brake 600 can achieve high-torque locking of the output wheel 300, thereby achieving joint locking. In other words, when the same torque locking of the output wheel 300 is required, only the relatively smaller second brake 600 needs to be used to lock the driven wheel 400 to achieve locking of the output wheel 300. This reduces the size and space occupied by the second brake 600, facilitating a reduction in the size of the rotary joint or other electromechanical systems.

[0062] Specifically, the transmission ratio between the driven wheel 400 and the output wheel 300 can be set according to actual needs. For example, the transmission ratio can be set to 1.5, 2, 2.5 or 3.

[0063] In one embodiment, see Figure 6 The pitch circle diameter of the driving wheel 200 is equal to the pitch circle diameter of the driven wheel 400. Thus, during the design process, the driving wheel 200 and the driven wheel 400 can be designed to have identical structures, thereby reducing the design and manufacturing costs of the driven wheel 400. Furthermore, during the entire transmission process, the driving wheel 200 and the driven wheel 400 rotate at the same speed, and during the braking process, the first brake 500 and the second brake 600 need to provide the same rotational torque. Therefore, the first brake 500 and the second brake 600 can also be designed to have the same structure, thereby reducing the design and manufacturing costs of the second brake 600.

[0064] In another embodiment of the present application, the pitch circle diameter of the driving wheel 200 and the pitch circle diameter of the driven wheel 400 can also be designed to be unequal. In this case, the rotational speeds of the driving wheel 200 and the driven wheel 400 are different, and the braking torques required to be output by the first brake 500 and the second brake 600 are different. However, as long as the tooth surface of the output wheel 300 can be in contact with the tooth surface of the driven wheel 400 during rotation, and the second brake 600 can lock the driven wheel 400 and the output wheel 300, it will be sufficient.

[0065] It should be noted that when the pitch circle diameters of the passive wheel 400 and the driving wheel 200 are equal, the models of the first brake 500 and the second brake 600 can be unified. When the pitch circle diameters of the passive wheel 400 and the driving wheel 200 are unequal, the sizes of the first brake 500 and the second brake 600 can be adjusted to achieve the same locking torque on both sides of the output wheel 300. For example, if the braking force required by the second brake 600 is 36Nm and the reduction ratio between the driving wheel 200 and the output wheel 300 is 6:1, the first brake 500 can be selected as a 6Nm model, and the reduction ratio between the passive wheel 400 and the output wheel 300 is 9:1, the second brake 600 can be selected as a 4Nm model, and the structural space can be adjusted accordingly.

[0066] In one embodiment, the rotary joint 1 further includes a controller, and the first brake 500, the second brake 600, and the driving member 100 are electrically connected to the controller. The controller is used to control the start and stop, forward rotation, and reverse rotation of the driving member 100, and to control the first brake 500 to clamp or release the active shaft 900, and to control the second brake 600 to clamp or release the passive shaft 1100. In addition, the controller is also used to control the first brake 500 and the second brake 600 to operate synchronously. That is, the controller simultaneously inputs control signals to the first and second controllers so that the first and second brakes 500 and 600 simultaneously clamp the active shaft 900 and the passive shaft 1100, thereby locking the active shaft 900 and the passive shaft 1100 at the same time. In other words, the second left tooth surface 311 and the second right tooth surface 312 of the output wheel 300 are locked at the same time, thereby improving the locking effect of the output wheel 300, preventing shaking, and eliminating locking backlash.

[0067] In one embodiment, the first brake 500 is a permanent magnet brake, and the second brake 600 is a permanent magnet brake. A permanent magnet brake is a device that uses electromagnetic force to brake or stop a shaft or rotating object. When current passes through the electromagnetic brake's magnetic coil, the electromagnetic force engages the brake pads, which release the brake disc, allowing the drive shaft to operate normally or start. When the current is cut off, the brake pads disengage from the brake disc, generating friction torque between the disc, the brake pads, and the flange, quickly stopping the drive shaft. Permanent magnet brakes have advantages such as low noise, fast response, long life, low heat generation, and low power consumption. In this embodiment, by configuring both the first brake 500 and the second brake 600 as permanent magnet brakes, when the controller sends a command to the first brake 500 and the second brake 600, the first brake 500 and the second brake 600 can quickly lock the driving shaft 900 and the driven shaft 1100, thereby immediately locking the output shaft 1000 and the output wheel 300. Furthermore, the permanent magnet brake is a rotary structure with a simple structure and is easy to install. Furthermore, the smaller the braking torque required, the smaller its diameter, thus occupying less space. It is understood that in other embodiments of the present application, the first brake 500 and the second brake 600 may also employ other types of brakes, as long as they can brake the driving shaft 900 and the driven shaft 1100. For example, these may be friction brakes, hydraulic brakes, or pneumatic brakes.

[0068] In one embodiment, the driving member 100 is a rotary motor, which is used to deliver rotary motion. It is understandable that in other embodiments of the present application, the driving member 100 may also be a rotary cylinder.

[0069] In one embodiment, see Figures 3 to 5The rotary joint 1 further includes a housing 800, a driving shaft 900, an output shaft 1000, and a driven shaft 1100. The driving member 100 is mounted on the housing 800, the driving shaft 900 is rotatably mounted on the housing 800, the driving wheel 200 is fixedly sleeved on the driving shaft 900, and the first brake 500 is connected to the driving shaft 900; the output shaft 1000 is rotatably mounted on the housing 800, the output wheel 300 is fixedly sleeved on the output shaft 1000; the driven shaft 1100 is rotatably mounted on the housing 800, the driven wheel 400 is fixedly sleeved on the driven shaft 1100, the second brake 600 is connected to the driven shaft 1100, and the damping structure 700 is connected to the driven shaft 1100.

[0070] Among them, the shell 800 serves as the supporting body of the entire rotary joint 1, and is used to support the driving member 100, the driving shaft 900, the driving wheel 200, the first brake 500, the output shaft 1000, the output wheel 300, the passive shaft 1100, the passive wheel 400 and the second brake 600 to ensure smooth movement of each structure.

[0071] The driving shaft 900 is used to support the driving wheel 200 and to form a connection between the driving wheel 200 and the housing 800, ensuring that the driving wheel 200 rotates smoothly in the housing 800. At the same time, the driving shaft 900 is also used to support the first brake 500 to enable the first brake 500 to brake the driving wheel 200. Specifically, the driving shaft 900 can be integrally connected to the driving wheel 200, or the driving wheel 200 can be fixed to the driving shaft 900 by a key or screw. It is understandable that in other embodiments of the present application, the driving shaft 900 may not be additionally provided, but instead a first connecting shaft may be extended outward from both axial ends of the driving wheel 200 to connect to the housing 800, and the first brake 500 may be provided on the first connecting shaft.

[0072] The output shaft 1000 is used to support the output wheel 300 and to form a connection between the output wheel 300 and the housing 800, ensuring that the output wheel 300 rotates smoothly in the housing 800. At the same time, the output shaft 1000 is also used to extend out of the housing 800 to connect with the next joint or end effector to transmit the rotational motion of the entire rotary joint 1 outward. Specifically, the output shaft 1000 can be integrally connected to the output wheel 300, or the output wheel 300 can be fixed to the output shaft 1000 by a key or screw. It is understandable that in other embodiments of the present application, the output shaft 1000 may not be additionally provided, but a second connecting shaft may be extended outward at both axial ends of the output wheel 300 to connect with the housing 800.

[0073] The passive shaft 1100 is used to support the passive wheel 400 and to form a connection between the passive wheel 400 and the housing 800 to ensure that the passive wheel 400 rotates smoothly in the housing 800. The passive shaft 1100 is also used to support the second brake 600 to achieve braking of the passive wheel 400 by the second brake 600, and the passive shaft 1100 is connected to the damping structure 700. The damping structure 700 can achieve rotational damping of the passive wheel 400 by applying a preset rotational resistance to the passive shaft 1100. Specifically, the passive shaft 1100 can be integrally connected to the passive wheel 400, or the passive wheel 400 can be fixed to the passive shaft 1100 by a key or screw. It is understandable that in other embodiments of the present application, the passive shaft 1100 may not be additionally provided, but a third connecting shaft may be extended outward at both axial ends of the passive wheel 400 to connect to the housing 800, and the third brake may be provided on the third connecting shaft.

[0074] In one embodiment, see Figure 3 and Figure 5 The rotary joint 1 also includes two first bearings 1200, which are respectively mounted on the housing 800. The opposite ends of the driving shaft 900 are respectively mounted on the two first bearings 1200. The driving shaft 900 is supported by the two first bearings 1200 to improve the rotation reliability and rotation accuracy of the driving shaft 900 and the driving wheel 200.

[0075] In one embodiment, see Figure 3 and Figure 4 The rotary joint 1 also includes two second bearings 1300, which are respectively mounted on the housing 800. The opposite ends of the output shaft 1000 are respectively mounted on the two second bearings 1300. The output shaft 1000 is supported by the two second bearings 1300 to improve the rotation reliability and rotation accuracy of the output shaft 1000 and the output wheel 300.

[0076] In one embodiment, see Figure 4 and Figure 5 The rotary joint 1 also includes two third bearings 1400, which are respectively mounted on the housing 800. The opposite ends of the passive shaft 1100 are respectively mounted on the two third bearings 1400. The passive shaft 1100 is supported by the two third bearings 1400 to improve the rotation reliability and rotation accuracy of the passive shaft 1100 and the passive wheel 400.

[0077] In one embodiment, the damping structure 700 is used to provide a friction load to the driven wheel 400; alternatively, the damping structure 700 is used to directly provide a torque load to the driven wheel 400. The friction load refers to friction with the driven wheel 400, which forms a knob torque through the friction force, so that the rotation of the driven wheel 400 is resisted, and this resistance is greater than the starting torque of the driving member 100, thereby ensuring that the tooth surface of the driven wheel 400 fits the tooth surface of the output wheel 300. The torque load directly provides a rotational pulling force in the opposite direction to the rotation of the driven wheel 400, and this rotational pulling force is less than the starting torque of the driving member 100, thereby ensuring that the tooth surface of the driven wheel 400 fits the tooth surface of the output wheel 300.

[0078] In one embodiment, see Figure 4 The damping structure 700 includes a steel ball 710, an elastic member 720, and a locking member 730. The steel ball 710 abuts one axial end of the driven shaft 1100, the elastic member 720 abuts between the steel ball 710 and the locking member, and the locking member 730 is threadedly mounted on the housing 800. By rotating the locking member 730 to compress the elastic member 720, the steel ball 710 and the driven shaft 1100 are pressed together, thereby generating a certain friction load on the driven shaft 1100. When the driven shaft 1100 is driven to rotate, this friction load provides a reverse torque to the driven shaft 1100.

[0079] Among them, the locking member 730 can be a locking screw, and the end of the locking screw abuts on the elastic member 720. By rotating the locking member 730, the locking member 730 is moved axially on the housing 800, thereby axially squeezing the elastic member 720, so that the elastic member 720 has elastic pressure on the steel ball 710, and then the steel ball 710 has axial pressure on the passive shaft 1100 to form a friction load. Specifically, an arc-shaped groove is formed on the passive shaft 1100, and at least a portion of the steel ball 710 is limited in the groove. In this embodiment, the provision of the steel ball 710 can not only provide a pressing friction force to the passive shaft 1100, but also prevent the steel ball 710 from damaging the passive shaft 1100.

[0080] Optionally, the elastic member 720 may be made of felt or foamed polyurethane, that is, elasticity is achieved by forming multiple pores in the block material, thereby ensuring the structural compression stability of the elastic member 720 .

[0081] In another embodiment of the present application, the damping structure 700 may also be a friction plate that abuts against one axial end of the passive wheel 400. Specifically, the friction plate is mounted on the housing 800 and is used to abut against one axial end of the passive shaft 1100, so that the passive shaft 1100 has friction resistance during rotation. In addition, in other embodiments, the damping structure 700 may also be a glass ball screw, or other structure that can provide rotational resistance to the passive shaft 1100. In other embodiments, the damping structure 700 may also be a friction plate that clamps the circumference of the passive shaft 1100 or the passive wheel 400.

[0082] In addition, in other embodiments, when the damping structure 700 is used to provide a torque load to the passive wheel 400, the damping structure 700 may be a torsion spring, or may be another force-applying structure with a set torque force, which is not limited here.

[0083] In one embodiment, see Figure 3 The shell 800 includes a base 810 and a cover 820. The base 810 has a mounting cavity 813 passing through the top. The cover 820 covers the top opening of the mounting cavity 813. The cover 820 and the base 810 form a detachable connection. For example, the cover 820 and the base 810 are locked by screws, or the cover 820 and the base 810 are clamped to each other.

[0084] The base 810 includes a bottom plate 811 and a side plate 812 formed around the edge of the bottom plate 811. The bottom plate 811 and the side plate 812 together enclose a mounting cavity 813. The cover plate 820 is connected to the side of the side plate 812 facing away from the bottom plate 811. The driving shaft 900, the output shaft 1000, and the driven shaft 1100 are rotatably mounted on the cover plate 820 and the bottom plate 811 at opposite ends. Two first bearings 1200, two second bearings 1300, and two third bearings 1400 are also mounted on the bottom plate 811 and the cover plate 820, respectively. The driving member 100 is mounted on the top outer side of the cover plate 820, and the damping structure 700 is mounted on the bottom plate 811.

[0085] In one embodiment, see Figure 3 and Figure 4 A mounting plate 1500 is also provided in the mounting cavity 813. The first brake 500 and the second brake 600 are respectively mounted on the outside of the active shaft 900 and the passive shaft 1100, and the stators of the first brake 500 and the second brake 600 are fixedly mounted on the mounting plate 1500, thereby ensuring that the first brake 500 and the second brake 600 are stably installed in the mounting cavity 813.

[0086] For details, please refer to Figure 3 and Figure 4A step 8121 is formed on the inner side wall of the side panel 812, and the edge of the mounting plate 1500 is placed on the step 8121, thereby limiting the position of the mounting plate 1500 in the mounting cavity 813. In addition, the mounting plate 1500 can be locked on the step 8121 by screws, or fixed on the step 8121 by gluing or clamping.

[0087] In one embodiment, see Figure 3 The bottom plate 811 is formed with a first mounting groove, in which a first bearing 1200 is received. A first stopper plate 910 extends from the bottom end of the driving shaft 900. The first stopper plate 910 abuts against the outer end surface of the first mounting groove, thereby axially limiting the first bearing 1200. Simultaneously, the first brake 500 is sleeved on the driving shaft 900 and axially abuts between the mounting plate 1500 and the first stopper plate 910.

[0088] In one embodiment, see Figure 4 The bottom plate 811 is formed with a second mounting groove, in which a third bearing 1400 is received. A second stopper 1110 extends from the bottom end of the driven shaft 1100. The second stopper 1110 abuts against the outer end surface of the second mounting groove, thereby axially limiting the third bearing 1400. Simultaneously, the second brake 600 is sleeved on the driven shaft 1100 and axially abuts between the mounting plate 1500 and the second stopper 1110.

[0089] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A rotary joint (1), characterized in that: include: A driving member (100) for outputting a rotational motion; A driving wheel (200) connected to the output end of the driving member (100); An output wheel (300) meshes with the driving wheel (200) for transmission; A driven wheel (400) meshes with the output wheel (300) for transmission; a damping structure (700), connected to the passive wheel (400) and used to provide a preset rotational resistance for the passive wheel (400); a first brake (500) for braking the driving wheel (200); The second brake (600) is used for braking the driven wheel (400).

2. The rotary joint (1) according to claim 1, characterized in that The pitch circle diameter of the driving wheel (200) is smaller than the pitch circle diameter of the output wheel (300); And / or, the pitch circle diameter of the driven wheel (400) is smaller than the pitch circle diameter of the output wheel (300).

3. The rotary joint (1) according to claim 1, characterized in that The pitch circle diameter of the driving wheel (200) is equal to the pitch circle diameter of the driven wheel (400); Alternatively, the pitch circle diameter of the driving wheel (200) is not equal to the pitch circle diameter of the driven wheel (400).

4. The rotary joint (1) according to any one of claims 1 to 3, characterized in that The first brake (500) is a permanent magnet brake; And / or, the second brake (600) is a permanent magnet brake.

5. The rotary joint (1) according to any one of claims 1 to 3, characterized in that: The rotary joint (1) further comprises a controller, the first brake (500), the second brake (600) and the driving member (100) are electrically connected to the controller respectively, and the controller controls the first brake (500) and the second brake (600) to work synchronously.

6. The rotary joint (1) according to any one of claims 1 to 3, characterized in that The damping structure (700) is used to provide a friction load to the passive wheel (400); Alternatively, the damping structure (700) is used to directly provide a torque load to the passive wheel (400).

7. The rotary joint (1) according to any one of claims 1 to 3, characterized in that The damping member is a friction plate abutting against one axial end of the driven wheel (400); Alternatively, the damping member is a friction plate that hugs the circumference of the passive wheel; Alternatively, the damping member is a torsion spring connected to the passive wheel (400).

8. The rotary joint (1) according to any one of claims 1 to 3, characterized in that: The rotary joint (1) further comprises: Housing (800); A driving shaft (900) is rotatably mounted on the housing (800), the driving wheel (200) is fixedly sleeved on the driving shaft (900), and the first brake (500) is connected to the driving shaft (900); and / or, An output shaft (1000) is rotatably mounted on the housing (800), and the output wheel (300) is fixedly sleeved on the output shaft (1000); and / or, The passive shaft (1100) is rotatably mounted on the housing (800), the passive wheel (400) is fixedly sleeved on the passive shaft (1100), the second brake (600) is connected to the passive shaft (1100), and the damping structure (700) is connected to the passive shaft (1100).

9. The rotary joint (1) according to claim 8, characterized in that The damping structure (700) includes a steel ball (710), an elastic member (720) and a locking member (730), wherein the steel ball (710) abuts against one axial end of the passive shaft (1100), the elastic member (720) abuts between the steel ball (710) and the locking member (730), and the locking member (730) is threadedly mounted on the housing (800).

10. A surgical robot, characterized in that: The invention comprises a rotary joint (1) as claimed in any one of claims 1 to 9.

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