Gravity balancer, joint and mechanical arm

Abstract

The embodiment of the invention relates to the field of medical instruments, and provides a gravity balancer, a joint and a mechanical arm. A volute spiral spring used for balancing the gravity of a load is arranged in the gravity balancer, a variable-diameter cone pulley assembly is arranged in the gravity balancer, the diameter change of the variable-diameter cone pulley assembly is matched with the torque provided by the volute spiral spring, and the drive shaft drives the volute spiral spring and the variable-diameter cone pulley assembly to be matched with each other to output constant force to balance the gravity of the load borne by the gravity balancer. Due to the fact that the diameter D of the variable-diameter cone pulley assembly is variable, for the same load, under the condition that the volute spiral spring provides non-constant torque T, the gravity balancer can output constant force F through matching of the change of the diameter D of the variable-diameter cone pulley assembly and the non-constant torque T provided by the volute spiral spring, so that the gravity of the load is stably balanced; the operation stability of the structure is improved, and the dragging process becomes smoother, so that the safety of the structure is improved.

Description

Technical Field

[0001] The present application relates to the field of medical devices, and more specifically, to a gravity balancer, a joint and a robotic arm. Background Art

[0002] In recent years, minimally invasive surgery has developed rapidly. Based on this, minimally invasive surgical robots have been widely favored for their advantages of less trauma and precise operation. As the key actuator of the surgical robot, the robotic arm affects the effect of the operation and the operating experience of medical staff. It needs to have high-precision movement ability and smooth dragging performance.

[0003] The vertical joint of the robot arm can be moved vertically with surgical instruments. The vertical joint of the robot arm is greatly affected by gravity, and the overall weight of the rear end of the vertical joint is also relatively heavy, so a large drag force is required to drag the surgical instruments. Therefore, in order to reduce the influence of gravity, a gravity balancer is usually set in the vertical joint to balance the gravity of the load.

[0004] In the prior art, in order to adapt to the gravity changes of different loads, a spiral spring is provided in the gravity balancer to balance the gravity of the load. However, the elastic force provided by the spiral spring changes nonlinearly and cannot adapt well to the balance of different loads.

[0005] Therefore, it is necessary to provide a gravity balancer that can better adapt to load changes and improve the balancing effect. Summary of the invention

[0006] The embodiments of the present application provide a gravity balancer, a joint and a mechanical arm, which can improve the balancing effect of the gravity balancer.

[0007] In a first aspect, a gravity balancer is provided, comprising a housing and a drive shaft, a volute spring and a variable diameter step pulley assembly mounted on the housing, wherein:

[0008] The scroll spring is sleeved on the driving shaft, one end of the scroll spring is connected to the driving shaft, and the other end is connected to the housing;

[0009] The variable diameter step pulley assembly is arranged at the end of the driving shaft, and the change in the diameter of the variable diameter step pulley assembly is adapted to the torque of the scroll spring, so that the gravity balancer outputs a constant force to balance the gravity of the load.

[0010] The gravity balancer provided in the embodiment of the present application is provided with a scroll spring for balancing the gravity of the load, and a variable diameter tower wheel assembly whose diameter change is adapted to the torque provided by the scroll spring is provided in the gravity balancer, and the scroll spring and the variable diameter tower wheel assembly cooperate with each other to output a constant force to balance the gravity of the load borne by the gravity balancer. Based on the formula A variable diameter tower wheel assembly whose diameter change is adapted to the torque provided by the scroll spring is provided in the gravity balancer. For the same load, when the scroll spring provides a non-constant torque T, the change in the diameter D of the variable diameter tower wheel assembly matches the torque T provided by the scroll spring, that is, the change in the diameter D of the variable diameter tower wheel assembly is basically consistent with the change in the torque T provided by the scroll spring, so that the gravity balancer can output a constant force F to stably balance the gravity of the load, so that the gravity balancer can adapt well to the balance of different loads and improve the balancing effect of the gravity balancer.

[0012] Optionally, the variable diameter step pulley assembly is formed with installation grooves distributed in a spiral line on the circumference, and the installation grooves are used to wind a transmission bar to connect the load through the transmission bar.

[0013] The gravity balancer provided in the embodiment of the present application forms an installation groove based on a spiral line design on the variable diameter tower wheel assembly, so that the diameter of the variable diameter tower wheel assembly is related to the overall radial dimension of the installation groove distributed in a spiral line. Since the design and process of the spiral line are relatively mature, the change in the diameter of the variable diameter tower wheel assembly can be designed relatively accurately, and the design difficulty and processing difficulty of the variable diameter tower wheel assembly can be reduced to reduce costs.

[0014] Optionally, the variable diameter step pulley assembly includes two variable diameter step pulleys, which are respectively arranged at two ends of the driving shaft in the same direction, and the diameter of the variable diameter step pulley changes with the rotation angle of the variable diameter step pulley.

[0015] The gravity balancer provided in the embodiment of the present application, the variable diameter tower pulley assembly includes two variable diameter tower pulleys respectively arranged at both ends of the driving shaft in the same direction, and the diameter of each variable diameter tower pulley changes with the rotation angle of the variable diameter tower pulley, so that the change in the diameter of the variable diameter tower pulley assembly can be adapted to the torque provided by the spiral spring. Moreover, by realizing the movement of the mobile device through the two variable diameter tower pulleys arranged at both ends of the driving shaft, the overall force of the mobile device and the gravity balancer can be relatively balanced, which is conducive to the stable operation of the structure.

[0016] Optionally, the gravity balancer further comprises:

[0017] A locking device, one end of which is connected to the housing, and the other end of which is used to lock the variable diameter step pulley to prevent the variable diameter step pulley from rotating.

[0018] The gravity balancer provided in the embodiment of the present application can prevent the rotation of the variable diameter tower wheel through the locking device to avoid the elastic force of the pre-tightened spiral spring driving the drive shaft to drive the variable diameter tower wheel to rotate, thereby ensuring the stability of the structure.

[0019] Optionally, at least one of the variable diameter step pulleys is provided with a slot, and the other end of the locking device is used to cooperate with the slot to lock the variable diameter step pulley, and the slot is provided on the radial structure of the maximum circumference of the variable diameter step pulley.

[0020] The gravity balancer provided in the embodiment of the present application cooperates with the locking device through the card slot set on the variable diameter tower wheel, and has a simple structure and is easy to operate; moreover, since the diameter of the radial structure of the largest circumference of the variable diameter tower wheel is the largest, it means that the radial structure of the largest circumference of the variable diameter tower wheel is closest to the locking device. In this way, the force used when pressing or lifting the locking device is minimal, which is convenient for user operation and improves user experience.

[0021] Optionally, at least one of the variable diameter step pulleys is sleeved on the driving shaft, and a step pulley pressure plate is provided on the end face of at least one of the variable diameter step pulleys, the step pulley pressure plate includes a plurality of positioning structures, the step pulley pressure plate is connected to the variable diameter step pulley via the plurality of positioning structures, and the step pulley pressure plate is connected to the driving shaft.

[0022] The gravity balancer provided in the embodiment of the present application has a variable diameter tower pulley sleeved on the driving shaft, and then the variable diameter tower pulley is fixed to the driving shaft through a tower pulley pressure plate, which can reduce the axial installation space of the gravity balancer in the driving shaft, and can reduce the size of the entire gravity balancer, thereby reducing the installation space of the gravity balancer in the joint. For joints of the same size, the space freed up by the gravity balancer can allow the mobile device to have more movement stroke, that is, the movement stroke of the mobile device can be increased. In addition, this structure is very suitable for scenarios where the size of the drive shaft end is small, and can solve the problem that it is inconvenient to directly fix the variable diameter tower pulley on the drive shaft due to the small size of the drive shaft end.

[0023] In addition, the multiple positioning structures of the tower wheel pressure plate can not only realize the connection between the tower wheel pressure plate and the variable diameter tower wheel, but also play a role in adjusting the installation angle of the variable diameter tower wheel. When pre-tightening the spiral spring, it is necessary to pre-tighten the spiral spring by rotating the two variable diameter tower wheels. During installation, when one variable diameter tower wheel has adjusted the installation angle, the other variable diameter tower wheel also needs to be adjusted to the same installation angle, so that the installation angles of the two variable diameter tower wheels can be guaranteed to be consistent. When the installation angle of the other variable diameter tower wheel is adjusted, if there is no positioning structure adapted to the installation angle on the tower wheel pressure plate, the stability of the structure will be greatly affected. Therefore, the installation angle of the variable diameter tower wheel can be adjusted by multiple positioning structures so that the installation angles of the two variable diameter tower wheels remain consistent. It can be understood that, in theory, the more the number of positioning structures, the more conducive it is to finely adjust the installation angle of the variable diameter tower wheel, because the more the number of positioning structures, the smaller the angle between the two adjacent positioning structures, and the installation angle of the variable diameter tower wheel can be adjusted within a smaller angle range.

[0024] Optionally, the gravity balancer further includes a motor disposed in the housing, and the motor is connected to the drive shaft to drive the drive shaft to rotate.

[0025] The gravity balancer provided in the embodiment of the present application has a motor disposed in a housing, and the motor is integrated with other components of the gravity balancer, thereby realizing integrated assembly of the motor and other components, making the structural layout more compact, and can reduce the space occupied by other components of the gravity balancer and the motor in the joints. For joints of the same size, the extra space vacated by the integrated assembly of the gravity balancer can allow the mobile device to have more movement range, that is, the movement range of the mobile device can be increased.

[0026] Optionally, the gravity balancer further comprises an angle detection device, which is disposed on the variable diameter step pulley assembly and is used to detect the rotation angle of the variable diameter step pulley assembly.

[0027] In a second aspect, a joint is provided, comprising a fixing device, a moving device and a gravity balancer as implemented in any one of the above-mentioned first aspects, wherein the moving device is slidably connected to the fixing device, and the variable diameter step pulley assembly of the gravity balancer can drive the moving device to move in a vertical direction relative to the fixing device.

[0028] Optionally, the mobile device includes an installation device, which includes mutually connected installation parts and a fault detection device, the installation parts are connected to the gravity balancer through a transmission bar, and the fault detection device is used to detect the connection status of the transmission bar to detect whether the gravity balancer is operating normally, and the connection status of the transmission bar includes a normal connection state and an abnormal connection state.

[0029] The joint provided in the embodiment of the present application has a fault detection device in the installation device. The fault detection device can detect the connection status of the transmission bar, thereby detecting whether the gravity balancer is operating normally, so that the operation of the joint can be stopped in time when the gravity balancer is not operating normally, thereby improving the safety of the structure operation.

[0030] Optionally, the fault detection device comprises an elastic member, a swing rod and a sensor, one end of the swing rod is connected to the mounting member, and the sensor and the elastic member are arranged on the swing rod;

[0031] When the transmission bar is in the normal connection state, the rocker arm presses the elastic member, and the sensor is in the on state; when the transmission bar is in the abnormal connection state, the elastic member releases energy to reset the rocker arm, and the sensor is in the off state.

[0032] The joint provided in the embodiment of the present application, in the above-mentioned fault detection device, realizes the detection of the state of the transmission bar through the cooperation between the elastic part, the rocker rod and the sensor 3123 to achieve the detection of the state of the gravity balancer, and the structure is simple and easy to implement.

[0033] Optionally, the elastic member is arranged at an end of the rocker arm away from the mounting member.

[0034] In the joint provided in the embodiment of the present application, when the elastic part is arranged at the end of the rocker arm away from the mounting part, since the transmission bar is installed on the mounting part, the elastic part and the transmission bar can form a better seesaw form. When the state of the transmission bar changes, the state of the elastic part will change significantly, which is conducive to the sensor to quickly detect the state change of the elastic part and improve the detection sensitivity.

[0035] In a third aspect, a robotic arm is provided, comprising a joint as in any one of the implementations of the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic structural diagram of the joint provided in the embodiment of the present application.

[0037] Figure 2 It is a schematic state diagram of the joint provided in the embodiment of the present application in a fully retracted state and a fully extended state.

[0038] Figure 3 It is a schematic structural diagram of a joint without a cover plate provided in an embodiment of the present application.

[0039] Figure 4 yes Figure 3 Cross-section view from AA perspective.

[0040] Figure 5 It is a schematic structural diagram of a mobile device provided in an embodiment of the present application.

[0041] Figure 6 It is a schematic structural diagram of an installation device in a mobile device provided in an embodiment of the present application.

[0042] Figure 7 It is a schematic structural diagram of the gravity balancer provided in the embodiment of the present application at various angles.

[0043] Figure 8 It is a cross-sectional view of the gravity balancer provided in an embodiment of the present application.

[0044] Fig. 9 and Fig.10 It is a schematic structural diagram of the variable diameter step pulley provided in an embodiment of the present application.

[0045] Fig.11It is a cross-sectional view of the variable diameter step pulley provided in an embodiment of the present application.

[0046] Fig.12 It is a schematic diagram of the functional relationship between the diameter of the variable diameter step pulley and the rotation angle of the variable diameter step pulley provided in an embodiment of the present application.

[0047] Reference numerals

[0048] 100. Joints;

[0049] 1. Gravity balancer; 11. Housing; 121. Drive shaft; 122. First bearing cap; 123. Second bearing cap; 13. Volute spring; 14. Variable diameter tower pulley assembly; 141. Variable diameter tower pulley; 141a. First variable diameter tower pulley; 141b. Second variable diameter tower pulley; 1411. Mounting slot; 1412. Clamping slot; 15. Tower pulley pressure plate; 151. Positioning structure; 16. Locking device; 17. Motor; 171. Motor stator; 172. Motor rotor; 18. Angle detection device; 181. Code disk support; 182. Code disk; 183. Read head support; 184. Read head;

[0050] 2. Fixing device; 21. Base; 22. Guide rail; 23. Armature plate;

[0051] 3. Moving device; 31. Mounting device; 311. Mounting member; 313. Fixing member; 314. Rotating shaft; 312. Fault detection device; 3121. Elastic member; 3122. Rocker; 3123. Sensor; 32. Lifting column; 33. Adapter plate; 34. Linear detection device; 351. First reinforcing rib; 352. Second reinforcing rib; 361. First brake; 3611. Coil; 3612. Shrapnel; 362. Second brake; 3621. Braking rack; 3622. Spring; 363. Sliding block;

[0052] 4. Transmission bar. DETAILED DESCRIPTION

[0053] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0054] The prior art gravity balancer is equipped with a spiral spring. The elastic force provided by the spiral spring varies nonlinearly. For the same load, the torque it provides is not constant and cannot balance the gravity of the same load well. As a result, the spiral spring cannot adapt to the balance of different loads well, affecting the balancing effect of the gravity balancer.

[0055] Based on this, an embodiment of the present application provides a new gravity balancer, in which a spiral spring for balancing the gravity of the load is provided, and a variable diameter tower wheel assembly whose diameter change is adapted to the torque provided by the spiral spring is provided in the gravity balancer. Since the diameter D of the variable diameter tower wheel assembly is variable, according to the formula T=F*D / 2, for the same load, when the spiral spring provides a non-constant torque T, through the mutual cooperation of the change in the diameter D of the variable diameter tower wheel assembly and the torque T provided by the spiral spring, the gravity balancer can output a constant force F to stably balance the gravity of the load, so that the gravity balancer can adapt well to the balance of different loads and improve the balancing effect of the gravity balancer.

[0056] It should be understood that although the gravity balancer proposed in the background art is applied to a vertical joint, it should not be limited to the embodiments of the present application, and the gravity balancer can also be applied to other structures for balancing gravity. For example, the gravity balancer can also be applied to the gravity moment balance of a rotary switch, etc.

[0057] In addition, when the gravity balancer is applied to the vertical joint, the vertical joint can be applied not only to minimally invasive surgical robots, but also to other equipment that requires vertical movement and dragging, and the embodiments of the present application do not impose any limitations.

[0058] To facilitate understanding, first, combine Figures 1 to 6 , taking the scenario where the gravity balancer is applied to a vertical joint as an example, the overall structure of the joint provided by the embodiment of the present application is described. Figures 7 to 12 , the gravity balancer provided in the embodiment of the present application is described in detail.

[0059] Figure 1 It is a schematic structural diagram of the joint provided in the embodiment of the present application. Figure 2 is a schematic state diagram of a joint in a fully extended state and a fully extended state provided by an embodiment of the present application. Figure 2 (a) in the figure shows a joint in a fully extended state. Figure 2 (b) in the figure shows a schematic diagram of the joint in a fully expanded state. Figure 3 It is a schematic structural diagram of a joint without a cover plate provided in an embodiment of the present application.

[0060] refer to Figures 1 to 3 , the joint 100 includes a gravity balancer 1 (such as Figure 3As shown), a fixing device 2, and a moving device 3. The gravity balancer 1 is fixedly arranged in the fixing device 2. For example, the gravity balancer 1 is arranged on a side of the fixing device 2 away from the moving device 3. The gravity balancer 1 is transmission-connected to the moving device 3. The moving device 3 is slidingly connected to the fixing device 2, and the moving device 3 can move up and down in the vertical direction relative to the fixing device 2. Among them, the rotation of the variable diameter tower wheel assembly of the gravity balancer 1 can drive the moving device 3 to move in the vertical direction relative to the fixing device 2.

[0061] When the joint 100 is configured in a robot arm, one end of the joint 100 is connected to the previous joint of the robot arm, and the other end is connected to the next joint of the robot arm. Figure 1 and Figure 2 The upper end of the position shown in the figure) is connected to the upper joint of the robot arm, and the mobile device 3 is at the end away from the gravity balancer 1 (i.e. Figure 1 and Figure 2 The lower end of the orientation shown) is connected to the next joint of the robotic arm.

[0062] It should be understood that the vertical direction mentioned in the embodiments of the present application is the direction in which the gravity of the object is located.

[0063] refer to Figure 2 (a) and Figure 3 When the mobile device 3 does not move, the mobile device 3 can be retracted to the bottom of the gravity balancer 1 and accommodated in the fixing device 2. When the mobile device 3 moves downward along the vertical direction and reaches the downward limit position, the mobile device 3 is in a fully expanded state, such as Figure 2 When the moving device 3 moves upward in the vertical direction to the upper limit position, the moving device 3 continues to retract to the bottom of the gravity balancer 1, as shown in (b) in FIG. Figure 2 As shown in (a) in the figure, the joint moves by reciprocating motion.

[0064] Figure 4 yes Figure 3 Cross-section view from AA perspective. Figure 5 It is a schematic structural diagram of a mobile device provided in an embodiment of the present application.

[0065] refer to Figure 3 and Figure 4 The fixing device 2 includes a base 21, and a cavity is formed in the base 21 for accommodating the gravity balancer 1, the moving device 3 and other structures of the fixing device 2 (for example, the guide rail 22, the armature plate 23 and other structures of the fixing device 2).

[0066] Exemplarily, two guide rails 22 are arranged in parallel on the bottom surface of the base 21 for supporting the moving device 3 to move in the vertical direction.

[0067] Exemplarily, a groove (not shown) is provided on the bottom surface of the base 21 , and an armature plate 23 is embedded in the groove for cooperating with a first brake 361 (described below) of the mobile device 3 to achieve braking and movement of the mobile device 3 .

[0068] Exemplarily, a gravity balancer 1 is installed above the cavity of the base 21 to balance the gravity of the mobile device 3 and the structure mounted on the mobile device 3 .

[0069] Exemplarily, the base 21 is also provided with a sterile cover interface (not shown in the figure) for installing the sterile cover to sterilely isolate the robotic arm from the patient.

[0070] The structure of the fixing device 2 in the above example is only for illustrative purposes and should not be construed as limiting the embodiments of the present application. The fixing device 2 may include more components or structures.

[0071] refer to Figures 3 to 5 The moving device 3 includes a lifting column 32 and an adapter plate 33 . Exemplarily, the adapter plate 33 is disposed at one end of the lifting column 32 close to the gravity balancer 1 .

[0072] The end of the mobile device 3 away from the gravity balancer 1 is used to connect other joints of the robot arm. Specifically, the lifting column 32 in the mobile device 3 is at the end away from the gravity balancer 1 (for example, Figures 3 to 5 The lower end of the lifting column 32 in the orientation shown in FIG. 1 is used to connect other joints of the mechanical arm. For example, the lifting column 32 can be a hollow structure to minimize the gravity borne by the gravity balancer 1.

[0073] In an embodiment of the present application, various structures can be installed on the adapter plate 33 to realize various functions of the mobile device 3 (for example, a sliding connection between the mobile device 3 and the fixed device 2, a braking function of the mobile device 3, detecting the moving position of the mobile device 3, a transmission connection between the mobile device 3 and the gravity balancer 1, etc.).

[0074] The adapter plate 33 can be in any shape, for example, an L-shaped structure (such as Figure 5 As shown), flat structure, curved structure, etc., without any limitation here.

[0075] In some embodiments, reference Figure 5 A plurality of sliders 363 are provided on one side of the adapter plate 33. The plurality of sliders 363 cooperate with the guide rail 22 of the fixing device 2. The sliding connection between the moving device 3 and the fixing device 2 is realized through the adapter plate 33, so that the moving device 3 can move in the vertical direction relative to the fixing device 2.

[0076] In some embodiments, reference Figure 5A first reinforcing rib 351 and a second reinforcing rib 352 are respectively provided on two side surfaces of the adapter plate 33 to improve the supporting rigidity of the adapter plate 33 .

[0077] In some embodiments, reference Figure 5 A straight line detection device 34 is provided on the first reinforcing rib 351 , and the straight line detection device 34 cooperates with the scale provided on the base 21 of the fixing device 2 to detect the position of the moving device 3 moving in the vertical direction.

[0078] In some embodiments, reference Figure 3 and Figure 5 , a first brake 361 is provided on the adapter plate 33 for achieving braking and movement of the mobile device 3. Exemplarily, when the adapter plate 33 is in an L-shaped structure, the first brake 361 may be provided in the middle area of ​​the L-shaped structure.

[0079] In one example, the first brake 361 is an adsorption brake. The first brake 361 includes a permanent magnet (not shown in the figure), a coil 3611 and a spring 3612 (such as Figure 5 When the power is turned off, the end surface of the first brake 361 and the armature plate 23 of the fixing device 2 are strongly adsorbed to generate friction to prevent the movement of the moving device 3, and the spring sheet 3612 bends; when the power is turned on, the spring sheet 3612 releases the elastic force, so that the end surface of the first brake 361 is out of contact with the armature plate 23, and the moving device 3 can move normally.

[0080] Exemplarily, there may be a plurality of first brakes 361. For example, there are two first brakes 361 arranged in a vertical direction.

[0081] refer to Figure 3 and Figure 4 In some embodiments, a second brake 362 is further disposed on the adapter plate 33. For example, the second brake 362 may be disposed in a region adjacent to the second reinforcing rib 352 or on the second reinforcing rib 352.

[0082] In one example, the second brake 362 is a latch-type brake. The second brake 362 includes a block, an electromagnet (not shown), a brake rack 3621 and a spring 3622 (such as Figure 4 When the power is on, the electromagnet pulls the block away from the brake rack 3621, and the mobile device 3 can move up and down; when the power is off, the spring 3622 pushes the block into the teeth of the brake rack 3621 to prevent the mobile device 3 from moving downward due to gravity.

[0083] The second brake 362 is a one-way holding brake, which can work simultaneously with the first brake 361 to ensure the movement safety of the entire joint with a redundant configuration. That is, when one brake 362 fails and fails to function, the other brake can realize the braking and movement of the mobile device 3 to ensure the movement safety of the joint as much as possible.

[0084] Figure 6 It is a schematic structural diagram of an installation device in a mobile device provided in an embodiment of the present application.

[0085] refer to Figure 5 and Figure 6 In some embodiments, the mobile device 3 includes a mounting device 31, and the mounting device 31 is used to connect with the gravity balancer 1 through the transmission bar 4, so as to connect the mobile device 3 with the gravity balancer 1. The mounting device 31 is connected with the lifting column 32. For example, the mounting device 31 is arranged on the adapter plate 33 and connected with the lifting column 32 through the adapter plate 33. One end of the mounting device 31 is connected with the adapter plate 33, and the other end is connected with the gravity balancer 1 through the transmission bar 4 (for example, a wire rope).

[0086] Here, the transmission bar 4 can be, for example, a transmission belt, a rope (for example, a steel wire rope), a chain, or the like, which can be connected and move relatively smoothly under the action of an external force.

[0087] The number of the mounting devices 31 may be two, one mounting device 31 is connected to one transmission bar 4 , and the other mounting device 31 is connected to another transmission bar 4 .

[0088] For example, reference Figure 6 The mounting device 31 includes a mounting member 311 and a fixing member 313 that are connected.

[0089] The mounting member 311 is connected to the gravity balancer 1 through the transmission bar 4 to achieve the connection between the moving device 3 and the gravity balancer 1. In other words, the mounting member 311 is used to connect the transmission bar 4, and the transmission bar 4 is connected to the gravity balancer 1.

[0090] Exemplarily, the mounting member 311 may be a pre-tightening nut having a hollow structure, and the end of the transmission bar 4 may pass through the pre-tightening nut. Tightening the pre-tightening nut may straighten the transmission bar 4 so that the gravity balancer 1 can withstand gravity.

[0091] The fixing member 313 is connected to the adapter plate 33 to fix the mounting device 31 on the adapter plate 33 .

[0092] In some embodiments, reference Figure 6The installation device 31 also includes a fault detection device 312, one end of which is connected to the installation member 311, and the other end is connected to the fixing member 313. The fault detection device 312 is used to detect the connection state of the transmission bar 4 to detect whether the gravity balancer 1 is operating normally. The connection state of the transmission bar 4 includes a normal connection state and an abnormal connection state. The normal connection state of the transmission bar 4 can be a pre-tightened state or a tensioned state, and the abnormal connection state of the transmission bar 4 can be a loose state or a broken state.

[0093] Since the installation device 31 is provided with a fault detection device 312, the connection status of the transmission bar 4 can be detected by the fault detection device 312, so as to detect whether the gravity balancer 1 is operating normally, so as to stop the operation of the joint in time when the gravity balancer 1 is operating abnormally, thereby improving the safety of the structure operation.

[0094] In one example, reference Figure 6 The fault detection device 312 includes an elastic member 3121, a swing rod 3122 and a sensor 3123. One end of the swing rod 3122 is connected to the mounting member 311, so that the swing rod 3122 can change with the state of the transmission bar 4. The other end of the swing rod 3122 is connected to the fixing member 313. For example, the swing rod 3122 can be movably connected to the fixing member 313 through a rotating shaft 314. For example, the rotating shaft 314 can be a pin. Under the drive of an external force, the swing rod 3122 can swing around the rotating shaft 314.

[0095] The sensor 3123 is disposed on the rocker arm 3122 . Exemplarily, the sensor 3123 may be disposed adjacent to the elastic member 3121 , so that the state change of the elastic member 3121 may be detected conveniently and accurately.

[0096] The elastic member 3121 is disposed on the swing rod 3122 . When the swing rod 3122 swings, the state of the elastic member 3121 changes. The state of the transmission bar 4 can be detected through the state of the elastic member 3121 , so as to detect the state of the gravity balancer 1 .

[0097] Exemplarily, the elastic member 3121 is disposed at one end of the swing rod 3122 away from the mounting member 311, or in other words, the elastic member 3121 is disposed at one end of the swing rod 3122 close to the fixing member 313. In this way, the elastic member 3121 and the transmission bar 4 can form a seesaw, and when the state of the transmission bar 4 changes, the state of the elastic member 3121 will change significantly, which is conducive to the sensor 3123 to quickly detect the state change of the elastic member 3121 and improve the detection sensitivity.

[0098] Taking the mounting member 311 as a pre-tightening nut as an example, the end of the transmission bar 4 passes through the pre-tightening nut, and tightening the pre-tightening nut can straighten the transmission bar 4 so that the gravity balancer 1 can withstand gravity. Based on the above-mentioned fault detection device 312, when the transmission bar 4 is in a normal connection state (for example, a pre-tightened state or a tensioned state), the gravity balancer 3 bears force through the transmission bar 4, and the swing rod 3122 will swing in a direction away from the fixing member 313 (such as Figure 6 In the swing direction 1 shown in the figure, the swing rod 3122 presses the elastic member 3121, and at this time, the sensor 3123 is in the on state; when the transmission bar 4 is in an abnormal connection state (for example, a loose state or a broken state), the gravity balancer 3 does not bear force through the transmission bar 4, and the elastic member 3121 releases energy to reset the swing rod 3122, and the swing rod swings in the direction close to the fixing member 313 (as shown in the figure). Figure 6 The swing direction 2) is shown, at this time, the sensor 3123 is in the disconnected state.

[0099] That is to say, when the sensor 3123 is in the on state, it means that the transmission bar 4 is in a normal state, which also means that the gravity balancer 1 can bear the force, and the gravity balancer 1 is in a normal state and operates well. When the sensor 3123 is in the off state, it means that the transmission bar 4 is in an abnormal state, which also means that the gravity balancer 1 cannot bear the force, and the gravity balancer 1 is in an abnormal state and has a serious fault.

[0100] It should be noted that Figure 6 The fault detection device 312 in the installation device 31 shown detects that the gravity sensor 1 is in a normal state. At this time, the gravity balancer 3 bears the load normally through the transmission bar 4, the transmission bar 4 is in a normal connection state (for example, a pre-tightened state or a tensioned state), the rocker arm 3122 presses the elastic part 3121, and the sensor 3123 is in an on state.

[0101] In the above-mentioned fault detection device 312, the state of the transmission bar 4 is detected through the cooperation between the elastic member 3121, the rocker rod 3122 and the sensor 3123 to detect the state of the gravity balancer 1. The structure is simple and easy to implement.

[0102] Figure 7 It is a schematic structural diagram of the gravity balancer provided in the embodiment of the present application at various angles. Figure 8 It is a cross-sectional view of the gravity balancer provided in an embodiment of the present application.

[0103] refer to Figure 7 and Figure 8 The gravity balancer 1 includes a housing 11 and a drive shaft 121 (such as Figure 8 As shown), spiral spring 13 (as Figure 8As shown) and the variable diameter tower wheel assembly 14, the driving shaft 121 can drive the spiral spring 13 and the variable diameter tower wheel assembly 14, and the spiral spring 13 and the variable diameter tower wheel assembly 14 cooperate with each other so that the gravity balancer 1 outputs a constant force to balance the gravity of the load borne by the gravity balancer 1.

[0104] The housing 11 is formed with a receiving cavity, and the receiving cavity contains, for example, a drive shaft 121, a spiral spring 13 and other related components. The shape of the housing 11 can be any shape, and no limitation is made here. For example, the housing 11 is cylindrical.

[0105] The driving shaft 121 is used to drive the variable diameter step pulley assembly 14 to rotate and cause the spiral spring 13 to deform.

[0106] Exemplarily, the drive shaft 121 is connected to the housing 11 through a bearing and a bearing cover. The bearing is connected to the drive shaft 121 and the bearing cover respectively, and the bearing is connected to the housing 11.

[0107] refer to Figure 8 The gravity balancer 1 includes two bearings (not shown in the figure), two bearing covers (referred to as the first bearing cover 122 and the second bearing cover 123), one end of the drive shaft 121 is connected to the housing 11 through a bearing and the first bearing cover 122, and the other end of the drive shaft 121 is connected to the housing 11 through another bearing and the second bearing cover 123.

[0108] The spiral spring 13 is used to provide a torque for balancing the gravity of the load, and can also provide torques in different ranges to balance loads of different gravity, thereby increasing the load adjustment range of the gravity balancer 1 .

[0109] refer to Figure 8 The volute spring 13 is annular in structure and is sleeved on the drive shaft 121. One end of the volute spring 13 is connected to the drive shaft 121, and the other end is connected to the housing 11. Exemplarily, the volute spring 13 includes an inner hook and an outer hook, the outer hook is fixedly connected to the housing 11, and the inner hook is fixedly connected to the drive shaft 121, so as to realize the connection between the volute spring 13 and the housing 11 and the drive shaft 121. When the drive shaft 121 rotates, the volute spring 13 is deformed, or when the volute spring 13 is deformed, it drives the drive shaft 121 to rotate.

[0110] It should be noted that, before the joint 100 operates, the spiral spring 13 needs to be pre-tightened to a certain torque so that the gravity balancer 1 can bear the weight.

[0111] It should be understood that the spiral spring 13 can be disposed at any position of the driving shaft 121 , and no limitation is made herein.

[0112] The variable diameter step pulley assembly 14 is a structure with a continuously changing diameter. The change in the diameter of the variable diameter step pulley assembly 14 is adapted to the torque provided by the spiral spring 13, so that the gravity balancer 1 outputs a constant force to balance the gravity of the load. For the non-constant torque provided by the spiral spring 13, the variable diameter step pulley assembly 14 is used to cooperate with the spiral spring 13, so that the gravity balancer 1 outputs a constant force to stably balance the gravity of the load borne by the gravity balancer 1.

[0113] Among them, the variable diameter step pulley assembly 14 is arranged at the end of the driving shaft 121, the transmission bar 4 is wound on the variable diameter step pulley assembly 14, and the end of the transmission bar 4 is connected to the moving device 3, so as to realize the transmission connection between the variable diameter step pulley assembly 14 and the moving device 3 through the transmission bar 4, thereby realizing the transmission connection between the gravity balancer 1 and the moving device 3.

[0114] It should be understood that for the gravity balancer 1, the weight of the load it balances includes the weight of the mobile device 3 and the structure mounted on the mobile device 3. For example, the force output by the gravity balancer 1 is F, the weight of the mobile device 3 is G1, and the weight of the structure mounted on the mobile device 3 is G2, then F=G1+G2.

[0115] Due to its own characteristics, the torque provided by the volute spring 13 for the same load is not constant. The torque provided by the volute spring 13 will change with the rotation angle and fluctuate within a certain range. Based on the formula T=F*D2, it can be known that when D is constant and T is non-constant, the output force F is also constant. Since the change in the diameter D of the variable diameter tower wheel assembly 14 is adapted to the torque provided by the volute spring 13, for the same load, when the volute spring 13 provides a non-constant torque T, the change in the diameter D of the variable diameter tower wheel assembly 14 and the torque T of the volute spring 13 cooperate with each other, that is, the change in the diameter D of the variable diameter tower wheel assembly 14 is basically consistent with the change in the torque T provided by the volute spring 13, so that the gravity balancer 1 can output a constant force F to stably balance the gravity of the load, so that the gravity balancer can adapt well to the balance of different loads and improve the balancing effect of the gravity balancer.

[0116] It can be understood that when the balancing effect of the gravity balancer is improved, the stability and safety of the structure operation can be improved.

[0117] In the embodiment of the present application, the manner of making the change in the diameter of the variable-diameter step pulley assembly 14 adapt to the torque provided by the spiral spring 13 can be arbitrary and is not limited here.

[0118] In some embodiments, the variable diameter step pulley assembly 14 is formed with installation grooves distributed in a spiral line on its circumference, and the installation grooves are used to wind the transmission bar 4 so as to connect the load through the transmission bar 4 .

[0119] In the above example, a mounting groove based on a spiral line design is formed on the variable diameter step pulley assembly 14, so that the diameter of the variable diameter step pulley assembly 14 is related to the overall radial dimension of the mounting groove distributed in a spiral line. Since the design and process of the spiral line are relatively mature, the diameter change of the variable diameter step pulley assembly 14 can be designed relatively accurately, and the design difficulty and processing difficulty of the variable diameter step pulley 14 can be reduced to reduce costs.

[0120] In some embodiments, reference Figure 7 and Figure 8 The variable diameter step pulley assembly 14 includes two variable diameter step pulleys 141, which are respectively arranged at two ends of the driving shaft 121 in the same direction, and the diameter of the variable diameter step pulley 141 changes with the rotation angle of the variable diameter step pulley 141. The spiral spring 13 is located between the two variable diameter step pulleys 141.

[0121] The two reducing step pulleys 141 are arranged in the same direction, which means that the two reducing step pulleys 141 extend in the same direction, and both extend from one side to the other side in a direction parallel to the driving shaft 121. Figure 8 In the illustrated orientation, the two reducing step pulleys 141 extend from the left side to the right side of the drive shaft 121 in a direction parallel to the drive shaft 121 .

[0122] Fig. 9 and Fig.10 It is a schematic structural diagram of the variable diameter step pulley provided in an embodiment of the present application. Fig.11 It is a cross-sectional view of the variable diameter step pulley provided in an embodiment of the present application.

[0123] In the embodiment where the variable diameter step pulley assembly 14 includes two variable diameter step pulleys 141, refer to Figures 9 to 11 For each variable diameter step pulley 141, a mounting groove 1411 distributed in a spiral line is formed in the circumference of each variable diameter step pulley 141. The spiral line of each variable diameter step pulley 141 is a single spiral line.

[0124] For the variable diameter step pulley 141 formed with the installation groove 1411 distributed in a spiral line, the two variable diameter step pulleys 141 are arranged in the same direction, which can also be expressed as that the installation grooves 1411 of the two variable diameter step pulleys 141 extend in the same direction, and both extend from one side to the other side along the direction parallel to the driving shaft 121. Figure 8 In the illustrated orientation, the mounting grooves 1411 of the two reducing step pulleys 141 extend from the left side to the right side of the reducing step pulleys 141 in a direction parallel to the driving shaft 121 .

[0125] In this embodiment, the variable diameter step pulley assembly 14 includes two variable diameter step pulleys 141 respectively arranged at both ends of the driving shaft 121 in the same direction, and the diameter of each variable diameter step pulley 141 changes with the rotation angle of the variable diameter step pulley 141 (or the rotation angle of the driving shaft 121), so that the change in the diameter of the variable diameter step pulley assembly 14 can be adapted to the torque provided by the spiral spring 13. Moreover, by realizing the movement of the moving device 3 through the two variable diameter step pulleys 141 arranged at both ends of the driving shaft 121, the overall force of the moving device 3 and the gravity balancer 1 can be relatively balanced, which is conducive to the stable operation of the structure.

[0126] In order to more clearly illustrate the implementation principle, the above formula T=F*D / 2 is replaced by the function T of the rotation angle θ of the variable diameter step pulley 141 or the driving shaft 121. θ =F*D θ / 2, where T θ is the function of the torque of the spiral spring 13 as the rotation angle changes, D θ is a function of the diameter of the variable diameter step pulley 141 as the rotation angle changes. θ and D θ When the changes at any rotation angle are substantially consistent, the gravity balancer 1 can output a constant force at any rotation angle to stably balance the gravity of the load.

[0127] In the embodiment of the present application, the relationship between the diameter D of the variable diameter step pulley 141 and the position of the moving device 3 can be expressed as: Among them, D x The mobile device 3 is at the current position S x The diameter of the variable diameter step pulley 141, S x is the linear displacement of the moving device 3, D 0 is the diameter of the variable diameter step pulley 141 when the moving device 3 is at the starting point of the stroke (ie, the zero position), and k is the functional relationship between the diameter of the variable diameter step pulley 141 and the rotation angle of the variable diameter step pulley 141 .

[0128] Fig.12 Schematic diagram of the functional relationship between the diameter of the variable diameter step pulley 141 and the rotation angle of the variable diameter step pulley 141 provided in the embodiment of the present application. Fig.12 As shown, the rotation angle of the variable diameter step pulley 141 is proportional to the diameter of the variable diameter step pulley 141. When the rotation angle of the variable diameter step pulley 141 increases, the diameter of the variable diameter step pulley 141 increases. When the rotation angle of the variable diameter step pulley 141 decreases, the diameter of the variable diameter step pulley 141 decreases. If the variation law of the diameter of the variable diameter step pulley 141 and the rotation angle of the variable diameter step pulley 141 fluctuates slightly, the functional relationship between the two can be approximated as a straight line, and the slope is k=(D 2 -D 1 ) / (θ 2 -θ 1 ).

[0129] The variable diameter step pulley assembly 14 in the above example is only an example, and any structure that can make the change in the diameter of the variable diameter step pulley assembly 14 adapt to the torque is within the protection scope of the embodiment of the present application.

[0130] In other embodiments, the variable diameter step pulley assembly 14 may also include a variable diameter step pulley 141, which is disposed at one end of the driving shaft 121. In an embodiment in which a mounting groove distributed in a spiral line is formed in the circumference of the variable diameter step pulley 141, the mounting groove 1411 of the variable diameter step pulley 141 is distributed in a double spiral line. The mounting groove 1411 distributed in a double spiral line here can be understood as Fig.11 Two single helical installation grooves 1411 are stacked along the axial direction of the drive shaft 121, and the two single helical installation grooves 1411 are arranged in the same direction. In this structure, one transmission bar 4 is connected to the variable diameter step wheel 141, and the other transmission bar 4 is connected to the drive shaft 121, thereby realizing the connection between the gravity balancer 1 and the moving device 3.

[0131] In other embodiments, the mounting groove 1411 of the variable diameter step pulley 141 may also be formed based on other forms of curve designs, without any limitation herein, as long as the diameter of the variable diameter step pulley 141 can be changed.

[0132] In the embodiment where the variable diameter step pulley assembly 14 includes two variable diameter step pulley assemblies 141, in some embodiments, reference Figure 7 (a) and Figure 8 At least one variable diameter step pulley 141 is sleeved on the driving shaft 121, and at least one variable diameter step pulley 141 is provided with a step pulley pressure plate 15 on its end surface. The step pulley pressure plate 15 includes a plurality of positioning structures 151 (such as Figure 7 As shown in (a) in FIG. 1 , the step pulley plate 15 is connected to the variable diameter step pulley 141 through a plurality of positioning structures 151, and the step pulley plate 15 is connected to the drive shaft 121, so that the variable diameter step pulley 141 is fixed to the drive shaft through the step pulley plate 15. The plurality of positioning structures 151 are distributed along the circumference of the step pulley plate 15. Exemplarily, the plurality of positioning structures 151 are evenly distributed along the circumference of the step pulley plate 15.

[0133] In this embodiment, at least one reducing pulley 141 is sleeved on the drive shaft 121, which means that one or two reducing pulleys 141 are sleeved on the drive shaft 121. When one reducing pulley 141 is sleeved on the drive shaft 121, illustratively, another reducing pulley 141 can be fixedly disposed on the end surface of the drive shaft 121 to achieve the connection between the reducing pulley 141 and the drive shaft 121.

[0134] At least one of the end faces of the reducing step pulley 141 is provided with a step pulley pressure plate 15, which means that the end faces of one or two reducing step pulleys 141 are provided with a step pulley pressure plate 15. When the end face of one reducing step pulley 141 is provided with a step pulley pressure plate 15, the gravity balancer 1 includes one step pulley pressure plate 15, and when the end faces of two reducing step pulleys 141 are provided with a step pulley pressure plate 15, the gravity balancer 1 includes two step pulley pressure plates 15. In addition, when the end faces of two reducing step pulleys 141 are provided with a step pulley pressure plate 15 (that is, the gravity balancer 1 includes two step pulley pressure plates 15), each reducing step pulley 141 is sleeved on the driving shaft 121, and each reducing step pulley 141 is connected to the step pulley pressure plate 15 through the positioning structure 151 of the corresponding step pulley pressure plate 15.

[0135] For the sake of distinction and description, the two reducing pulleys 141 are respectively referred to as a first reducing pulley 141 a and a second reducing pulley 141 b . Taking the first reducing pulley 141 a as an example, the structure in which the reducing pulley 141 is fixed to the driving shaft 121 through the pulley pressure plate 15 is described.

[0136] refer to Figure 8 For the first reducing pulley 141a, the first reducing pulley 141a is sleeved on the end of the driving shaft 121, and the pulley pressure plate 15 is set on the end surfaces of the first reducing pulley 141a and the driving shaft 121. The pulley pressure plate 15 is respectively connected to the driving shaft 121 and the first reducing pulley 141a to fix the first reducing pulley 141a on the driving shaft 121 through the pulley pressure plate 15.

[0137] The step pulley pressing plate 15 is a plate-like structure, and its shape is not limited in any way. For example, the step pulley pressing plate 15 can be circular, square, etc.

[0138] In the above embodiment, the reducing tower wheel 141 is sleeved on the driving shaft 121, and then the reducing tower wheel 141 is fixed to the driving shaft 121 by the tower wheel pressure plate 15, which can reduce the axial installation space of the gravity balancer 1 on the driving shaft 121, and can reduce the size of the entire gravity balancer 1, thereby reducing the installation space of the gravity balancer 1 on the joint 100. For the joint 100 of the same size, the space vacated by the gravity balancer 1 can allow the moving device 3 to have more movement stroke, that is, the movement stroke of the moving device 3 can be increased; in addition, this structure is very suitable for the scenario where the end of the driving shaft 121 is smaller in size, and can solve the problem that the end of the driving shaft 121 is smaller in size and it is not convenient to directly fix the reducing tower wheel 141 on the driving shaft 121.

[0139] In the structure in which the step wheel pressure plate 15 is connected to the variable diameter step wheel 141 via a plurality of positioning structures 151, it should be understood that a structure (not shown in the figure) adapted to the positioning structure 151 is provided on the step wheel pressure plate 15, and the two cooperate to realize the connection between the step wheel pressure plate 15 and the variable diameter step wheel 141.

[0140] In the above embodiment, the multiple positioning structures 151 of the step pulley plate 15 can not only realize the connection between the step pulley plate 15 and the variable diameter step pulley 141, but also play a role in adjusting the installation angle of the variable diameter step pulley 141. When pre-tightening the spiral spring 13, it is necessary to pre-tighten the spiral spring 13 by rotating the two variable diameter step pulleys 141. During installation, when one variable diameter step pulley 141 has adjusted the installation angle (or installation position), the other variable diameter step pulley 141 also needs to be adjusted to the same installation angle, so as to ensure that the installation angles of the two variable diameter step pulleys 141 are consistent. When the installation angle of the other variable diameter step pulley 141 is adjusted, if there is no positioning structure 151 adapted to the installation angle on the step pulley plate 15, the stability of the structure will be greatly affected. Therefore, the installation angle of the variable diameter step pulley 141 can be adjusted by multiple positioning structures 151 so that the installation angles of the two variable diameter step pulleys 141 remain consistent. It can be understood that, in theory, a greater number of positioning structures 151 is conducive to finely adjusting the installation angle of the variable diameter tower wheel 141, because a greater number of positioning structures 151 means a smaller angle between two adjacent positioning structures 151, which allows the installation angle of the variable diameter tower wheel 141 to be adjusted within a smaller angle range.

[0141] As mentioned above, before operation, the volute spring 13 needs to be pre-tightened. In order to prevent the elastic force of the volute spring 13 from driving the drive shaft 121 to drive the variable diameter step pulley 141 to rotate, it is necessary to prevent the variable diameter step pulley 141 from rotating after the volute spring 13 is pre-tightened. Therefore, the embodiment of the present application proposes to prevent the rotation of the variable diameter step pulley 141 by a locking device.

[0142] In some embodiments, reference Figure 7 In (b), the gravity balancer 1 further includes a locking device 16, one end of which is connected to the housing 11, and the other end is used to lock the variable diameter step pulley 141 to prevent the variable diameter step pulley 141 from rotating. Exemplarily, the locking device 16 is disposed on one side of the radial direction of the variable diameter step pulley 141.

[0143] In the above embodiment, the locking device 16 can prevent the variable diameter step pulley 141 from rotating, so as to prevent the elastic force of the pre-tightened spiral spring 13 from driving the drive shaft 121 to drive the variable diameter step pulley 141 to rotate, thereby ensuring the stability of the structure;

[0144] Regarding the cooperation between the locking device 16 and the variable diameter step pulley 141, refer to Fig. 9At least one reducing step pulley 141 (for example, the second reducing step pulley 141b) is provided with a slot 1412, and the other end of the locking device 16 is used to cooperate with the slot 1412 to lock the reducing step pulley 141 to prevent the reducing step pulley 141 from rotating. The slot 1412 provided on the reducing step pulley 141 cooperates with the locking device 16, and the structure is simple and the operation is convenient.

[0145] In practice, the locking device 16 can be pressed toward the direction close to the card slot 1412, so that the end of the locking device 16 is stuck on the card slot 1412. Since the locking device 16 itself is fixed to the housing 11, the locking device 16 does not move, and therefore, the variable diameter step pulley 141 can be locked to prevent the variable diameter step pulley 141 from rotating. When the mobile device 3 is running, the locking device 16 is lifted toward the direction away from the card slot 1412, the locking device 16 is disengaged from the card slot 1412, and the variable diameter step pulley 141 can rotate normally.

[0146] One end of the locking device 16 is connected to the housing 11, and the locking device 16 may be directly connected to the housing 11, or may be indirectly connected through other components. For example, one end of the locking device 16 may be fixed to the bearing, and since the bearing is fixed to the housing 11, one end of the locking device 16 may be fixed to the housing 11 through the bearing.

[0147] A plurality of slots 1412 can be provided on the variable diameter step pulley 141. In theory, the more the better. In this way, when the variable diameter step pulley 141 is at any installation angle, there can be an adapted slot 1412 to cooperate with the locking device 16.

[0148] Exemplarily, the card slot 1412 can be a slot of any shape, such as a sawtooth shape, a rectangle, a trapezoid, etc.

[0149] It should be understood that the connection between the locking device 16 and the second variable diameter step pulley 141b shown in the figure is only for schematic illustration, and the locking device 16 can also be connected to the first variable diameter step pulley 141a without any limitation.

[0150] For the card slot 1412, illustratively, refer to Fig. 9 The slot 1412 is arranged on the radial structure of the maximum circumference of the variable diameter step pulley 141 .

[0151] Since the diameter of the radial structure of the largest circumference of the variable diameter tower wheel 141 is the largest, it means that the radial structure of the largest circumference of the variable diameter tower wheel 141 is closest to the locking device 16. In this way, the force used when pressing or lifting the locking device 16 is minimal, which facilitates user operation and improves user experience.

[0152] In some embodiments, the gravity balancer 1 further includes an angle detection device 18 disposed on the variable diameter step pulley assembly 14 . The angle detection device 18 is used to detect the rotation angle of the variable diameter step pulley assembly 14 .

[0153] When the variable diameter step pulley assembly 14 includes one variable diameter step pulley 141, the angle detection device 18 is disposed on the variable diameter step pulley 141. When the variable diameter step pulley assembly 14 includes two variable diameter step pulleys 141, the angle detection device 18 is disposed on any one of the variable diameter step pulleys 141. Figure 8 The angle detection device 18 is arranged on the second variable diameter step pulley 141b.

[0154] For example, reference Figure 8 , taking the angle detection device 18 provided on the second variable diameter step pulley 141b as an example. The angle detection device 18 is annular in structure, and is provided at the end of the second variable diameter step pulley 141b along the circumference of the second variable diameter step pulley 141b. The angle detection device 18 includes a code disc support 181, a code disc 182, a reader support 183 and a reader 184. The code disc 182 is fixed on the second variable diameter step pulley 141b through the code disc support 181, the reader support 183 is fixed on the housing 11, and the reader 184 is connected to the reader support 183. When the code disc 182 rotates, the rotation angle of the second variable diameter step pulley 141b is obtained through the reader 184.

[0155] In other embodiments, the angle detection device 18 may also be disposed on the driving shaft 121 , and may also be capable of detecting the rotation angle of the variable diameter step pulley assembly 14 .

[0156] In some embodiments, reference Figure 8 The gravity balancer 1 further includes a motor 17 disposed in the housing 11 , one end of the motor 17 is connected to the housing 11 , and the other end of the motor 17 is connected to the driving shaft 121 to drive the driving shaft 121 to rotate.

[0157] In this embodiment, the motor 17 is arranged in the housing 11, and the motor 17 is integrated with other components of the gravity balancer 1, thereby realizing the integration of the motor 17 and other components, making the structural layout more compact, and can reduce the space occupied by other components of the gravity balancer 1 and the motor 17 in the joint 100. For the joint 100 of the same size, the extra space vacated by the integrated gravity balancer 1 can enable the mobile device 3 to have more movement range, that is, the movement range of the mobile device 3 can be increased.

[0158] For example, reference Figure 8The motor 17 is annular in structure and is located on one side of the volute spring 13. The motor 17 includes a motor stator 171 and a motor rotor 172. The motor stator 171 is connected to the housing 11, and the motor rotor 172 is connected to the drive shaft 121. When the motor 17 is running, the motor rotor 172 drives the drive shaft 121 to rotate.

[0159] In the above embodiment, since the spiral spring 13 is sleeved on the drive shaft 121, there will be a part of space on one side of the spiral spring 13. The motor 17 is designed to be a ring structure and is located on one side of the spiral spring 13. The motor 17 just utilizes the space on one side of the spiral spring 13, avoiding the problem of increasing the overall size of the gravity balancer 1 due to additional occupation of other space, which is more conducive to saving space and has a compact layout, so that the overall size of the gravity balancer 1 is more inclined to be miniaturized.

[0160] In some embodiments, the housing 11 is provided with a mounting structure for mounting a drive control unit, and the drive control unit is used to control the movement of the load. Exemplarily, the mounting structure may be a mounting hole, a mounting slot, or the like.

[0161] It should be understood that in the embodiments of the present application, unless otherwise clearly specified and limited, the terms "connection", "fixed connection", "contact" and the like should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above-mentioned various terms in the embodiments of the present application can be understood according to specific circumstances.

[0162] Exemplarily, for "connection", it can be various connection methods such as fixed connection, rotating connection, flexible connection, sliding connection, one-piece molding, electrical connection, contact connection, etc.; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal connection between two elements or the interaction relationship between two elements.

[0163] Exemplarily, for "fixed connection", one element can be directly or indirectly fixedly connected to another element; the fixed connection can include mechanical connection, welding, bonding or integrated molding, among which the mechanical connection can include riveting, bolting, threaded connection, key connection, snap connection, lock connection, plug-in and other methods, and the bonding can include adhesive bonding and solvent bonding and other methods.

[0164] Exemplarily, the interpretation of "contact" can be direct or indirect contact between one element and another element; in addition, the contact between the two elements described in the embodiments of the present application can be understood as contact within the allowable range of installation error, and there may be a very small gap caused by the installation error.

[0165] It should also be understood that the “parallel” or “perpendicular” described in the embodiments of the present application may be understood as “approximately parallel” or “approximately perpendicular”.

[0166] It should also be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly indicate the number of technical features indicated. Features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0167] In the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first feature is in direct contact with the second feature, or the first feature and the second feature are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0168] It should also be understood that the terms "inside", "outside", "top", "bottom", "front", "back", etc., indicating the orientation or positional relationship (if any) are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present 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 the present application.

[0169] In the embodiments of the present application, "at least one" means one or more, and "more than one" means two or more. "At least part of an element" means part or all of an element. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B may be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0170] It should be noted that, in the embodiments of the present application, the same figure mark is used to represent the same component or the same part. For the same parts in the embodiments of the present application, the figure may only mark one of the parts or components as an example. It should be understood that the figure mark also applies to other identical parts or components.

[0171] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims. In short, the above is only a preferred embodiment of the technical solution of the present application, and is not used to limit the protection scope of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A gravity balancer (1), It is characterized in that The invention comprises a housing (11), a driving shaft (121) installed on the housing (11), a spiral spring (13) and a variable diameter step pulley assembly (14), wherein: The volute spring (13) is sleeved on the drive shaft (121), one end of the volute spring (13) is connected to the drive shaft (121), and the other end is connected to the housing (11); The variable diameter step pulley assembly (14) is arranged at the end of the driving shaft (121), and the change in diameter of the variable diameter step pulley assembly (14) is adapted to the torque of the spiral spring (13), so that the gravity balancer (1) outputs a constant force to balance the gravity of the load.

2. The gravity balancer (1) according to claim 1, It is characterized in that The variable diameter step pulley assembly (14) is formed with mounting grooves (1411) distributed in a spiral line on the circumference, and the mounting grooves (1411) are used to wind the transmission bar (4) so ​​as to connect the load through the transmission bar (4).

3. The gravity balancer (1) according to claim 1, It is characterized in that The variable diameter step pulley assembly (14) comprises two variable diameter step pulleys (141), the two variable diameter step pulleys (141) are respectively arranged at two ends of the driving shaft (121) in the same direction, and the diameter of the variable diameter step pulley (141) changes with the rotation angle of the variable diameter step pulley (141).

4. The gravity balancer (1) according to claim 3, It is characterized in that The gravity balancer also includes: A locking device (16), one end of which is connected to the housing (11), and the other end of which is used to lock the variable diameter step pulley (141) to prevent the variable diameter step pulley (141) from rotating.

5. The gravity balancer (1) according to claim 4, It is characterized in that At least one of the variable diameter step pulleys (141) is provided with a slot (1412), and the other end of the locking device (16) is used to cooperate with the slot (1412) to lock the variable diameter step pulley (141), and the slot (1412) is provided on a radial structure of the maximum circumference of the variable diameter step pulley (141).

6. The gravity balancer (1) according to claim 3, It is characterized in that At least one of the variable diameter step pulleys (141) is sleeved on the driving shaft (121); the end surface of at least one of the variable diameter step pulleys (141) is provided with a step pulley pressure plate (15); the step pulley pressure plate (15) includes a plurality of positioning structures (151); the step pulley pressure plate (15) is connected to the variable diameter step pulley (141) via the plurality of positioning structures (151).

7. A gravity balancer (1) according to any one of claims 1 to 6, It is characterized in that The gravity balancer further comprises a motor (17) disposed in the housing (11); the motor (17) is connected to the drive shaft (121) to drive the drive shaft (121) to rotate.

8. The gravity balancer (1) according to any one of claims 1 to 6, It is characterized in that The gravity balancer further comprises an angle detection device (18) which is arranged on the variable diameter step pulley assembly (14) and is used to detect the rotation angle of the variable diameter step pulley assembly (14).

9. A joint (100) comprising a gravity balancer (1) as claimed in any one of claims 1 to 8, It is characterized in that It comprises a fixing device (2) and a moving device (3), wherein the moving device (3) is slidably connected to the fixing device (2), and the variable diameter step pulley assembly (14) of the gravity balancer (1) can drive the moving device (3) to move in a vertical direction relative to the fixing device (2).

10. The joint (100) according to claim 9, It is characterized in that The moving device (3) comprises a mounting device (31), wherein the mounting device (31) comprises a mounting member (311) and a fault detection device (312) which are connected to each other, wherein the mounting member (311) is connected to the gravity balancer (1) via a transmission bar (4), and the fault detection device (312) is used to detect a connection state of the transmission bar (4) to detect whether the gravity balancer (1) is operating normally, wherein the connection state of the transmission bar (4) comprises a normal connection state and an abnormal connection state.

11. The joint (100) according to claim 10, It is characterized in that The fault detection device (312) comprises an elastic member (3121), a swing rod (3122) and a sensor (3123); one end of the swing rod (3122) is connected to the mounting member (311); and the sensor (3123) and the elastic member (3121) are arranged on the swing rod (3122); When the transmission bar (4) is in the normal connection state, the swing rod (3122) presses the elastic member (3121), and the sensor (3123) is in the on state; when the transmission bar (4) is in the abnormal connection state, the elastic member (3121) releases energy to reset the swing rod (3122), and the sensor (3123) is in the off state.

12. The joint (100) according to claim 11, It is characterized in that The elastic member (3121) is arranged at an end of the swing rod (3122) away from the mounting member (311).

13. A robotic arm, It is characterized in that Comprising a joint (100) as claimed in any one of claims 9 to 12.

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