Gravity balancing mechanism, trolley base and surgical robot

Abstract

The present invention discloses a gravity balancing mechanism, a trolley base, and a surgical robot, which relate to the technical field of medical equipment. The balancing mechanism includes a crank mechanism and an elastic member. One end of the crank mechanism and one end of the elastic member are both fixed to a stationary component. The other end of the elastic member is connected to the input end of the crank mechanism to apply a linearly varying force to the crank mechanism. The output end of the crank mechanism is connected to a moving component. The crank mechanism transmits a linearly varying force so that the output end applies a force opposite to the direction of gravity of the moving component to the moving component. The present invention converts the elastic force of an ordinary compression spring into an output tension of a slider through the crank mechanism. By setting up the crank mechanism, not only can an almost constant balancing force be achieved using an ordinary spring, but also different rod lengths can be determined to enable the slider to output balancing forces of different sizes, thereby better meeting different gravity balancing requirements. The invention has strong versatility and can also meet the full life cycle of the equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of medical equipment, and in particular to a gravity balancing mechanism, a trolley base and a surgical robot. Background Art

[0002] With the continuous development of medical devices, computer technology, and control technology, minimally invasive surgery has become increasingly widely used due to its advantages such as minimal surgical trauma, short recovery time, and reduced patient pain. Minimally invasive surgical robots, with their high dexterity, high control precision, and intuitive surgical images, can avoid operational limitations such as hand tremors during filtering operations, making them widely applicable to surgical areas such as the abdominal, pelvic, and thoracic cavities.

[0003] Currently, minimally invasive surgical robots consist of a main control console and a slave manipulator arm. The main control console collects the doctor's operating signals, which are processed by the control system and then generate control signals for the slave manipulator arm, which then performs the surgical operation. The main control console can be deployed by manually pushing it. When pushing the main control console, to ensure that the main control console can pass through certain terrains, there needs to be a certain height difference between the console's universal casters and the lowest point of its chassis. After the main control console is deployed in place, the universal casters need to be locked to provide a more stable operating platform. At the same time, the pedal base, which is equipped with various control foot switches, needs to be lowered to the ground to make it more comfortable for the surgeon to use their feet. Since the pedal base has a certain weight, a gravity balancing mechanism is required to make it easier to control its rise. However, the space on the base is limited, so the volume of the gravity balancing mechanism is required to be relatively high.

[0004] Chinese patent CN217793334U discloses a doctor control platform, which includes a doctor trolley frame, a main operating arm installed on the doctor trolley frame and a display unit with adjustable height; the main operating arm is used by the doctor to operate to control the instrument to complete the operation; a trolley base is installed at the bottom of the doctor trolley frame; the doctor trolley frame includes an armrest, a column, a side push handle assembly and a fixing frame; two side push handle assemblies are arranged on the same side of the armrest; one end of the two side push handle assemblies is respectively connected to the end of the corresponding armrest, and the other end of the two side push handle assemblies is connected to the fixing frame; the display unit and / or the fixing frame are slidably connected to the side of the column. Among them, a solution for achieving gravity balance by setting up multiple balancing components is also disclosed, but the elastic component in this solution uses a constant force spring. The standard constant force spring on the market provides a standard constant tension, and the constant tension is relatively small. In the gravity balancing mechanism, the gravity to be balanced is large, so the structure uses two groups on each side, a total of eight constant force springs; and the constant tension of the standard constant force spring has a certain gradient, and it is difficult to better match the gravity to be balanced, and it is difficult to make the two exactly equal, unless the constant force spring is customized according to the gravity to be balanced, but the cost of customized constant force springs is high; and, since the balanced gravity is large, the constant force spring that provides a large constant tension generally has a short lifespan, which cannot cover the full life cycle of the equipment, so the structure needs to be replaced regularly, causing inconvenience. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a gravity balancing mechanism, a trolley base and a surgical robot.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A gravity balancing mechanism is assembled between a stationary component and a moving component and is used to balance the gravity of the moving component. The mechanism includes a crank mechanism and an elastic member. One end of the crank mechanism and one end of the elastic member are both fixed to the stationary component. The other end of the elastic member is connected to the input end of the crank mechanism to apply a linearly changing force to the crank mechanism. The output end of the crank mechanism is connected to the moving component. The crank mechanism transmits the linearly changing force so that the output end applies a force to the moving component in the opposite direction to the gravity of the moving component.

[0008] Based on the above technical solution, further, the stationary component includes a base, the crank mechanism includes a telescopic arm assembly, one end of the elastic member is fixed on the base, and the other end of the elastic member is docked with the input end of the telescopic arm assembly to apply a linearly changing force to the input end.

[0009] Based on the above technical solution, further, the telescopic arm assembly includes a first telescopic arm and a second telescopic arm, one end of the first telescopic arm is connected to the base through a fixed hinge, the other end of the first telescopic arm is connected to one end of the second telescopic arm through a movable hinge, and the other end of the second telescopic arm is connected to the moving part.

[0010] Based on the above technical solution, further, the crank mechanism also includes an output slider, the second telescopic arm is connected to the moving component through the output slider, and the second telescopic arm and the output slider are connected through a movable hinge.

[0011] Based on the above technical solution, further, a fixing portion is provided on the base, and the first telescopic arm is connected to the base via the fixing portion.

[0012] Based on the above technical solution, further, it also includes a guide mechanism, the guide mechanism includes a guide column, the guide column is installed on the base, and an elastic member is sleeved on the guide column.

[0013] Based on the above technical solution, further, the guide mechanism also includes a guide block and a guide rod, the guide rod is installed on the base, the guide block moves along the guide rod, and the guide column and the elastic member are jointly inserted into the guide block.

[0014] Based on the above technical solution, further, the interior of the base is a groove structure, the guide mechanism is located in the groove, and a first through hole is opened on the base, and a first guide hole is opened on the guide block. The guide column extends from the outside of the base through the first through hole to the inside of the groove until it is inserted into the first guide hole.

[0015] Based on the above technical solution, further, a second through hole is provided on the base, one end of the first telescopic arm is connected to a bearing, and the bearing is located in the second through hole.

[0016] Based on the above technical solution, further, an avoidance groove is provided at the bottom of the guide block, and the crank mechanism moves below the avoidance groove.

[0017] Based on the above technical solution, further, at least one second guide hole is opened on the guide block, one end of the guide rod is fixed to one side of the base, and the other end of the guide rod passes through the second guide hole and is fixed to the other side of the base.

[0018] Based on the above technical solution, further, the guide rod is also provided with an oil-free bushing, and the oil-free bushing is located in the second guide hole.

[0019] Based on the above technical solution, further, the elastic member is a spring that can provide a linearly changing force.

[0020] A trolley base comprises a gravity balancing mechanism, wherein the stationary component comprises a base frame, and the moving component comprises a control pedal.

[0021] A surgical robot comprises a trolley base.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention uses a crank mechanism to convert the elastic force of an ordinary compression spring into the output tension of a slider. After design and calculation, a specific appropriate rod length can be matched in a specific scenario, and the linearly changing elastic force provided by the ordinary compression spring can be converted into a nearly constant output tension at the output slider. The error can currently be controlled within 5%. Compared with the existing technology, this crank mechanism not only uses ordinary springs to achieve a nearly constant balancing force, but also can determine different rod lengths to make the slider output different amounts of balancing force, better meeting different gravity balance requirements. It has strong versatility. On the other hand, the lifespan of ordinary compression springs is much longer than that of constant force springs, and this mechanism can also meet the full life cycle of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A perspective view of the gravity balancing mechanism of the present invention from the front end perspective;

[0025] Figure 2 for Figure 1 AA cross-sectional view;

[0026] Figure 3 It is a structural diagram of the gravity balance mechanism of the prior art;

[0027] Figure 4 A perspective view of the gravity balancing mechanism of the present invention from the rear end perspective;

[0028] Figure 5 for Figure 3 BB cross-sectional view;

[0029] Figure 6 Schematic diagram of the structure of the base in the gravity balancing mechanism of the present invention;

[0030] Figure 7 for Figure 6 A schematic diagram of the structure of the relative angles of the base;

[0031] Figure 8 This is a structural diagram of the gravity balancing mechanism of the present invention with the base hidden;

[0032] Figure 9 This is a structural diagram of the gravity balance mechanism of the present invention in a retracted state;

[0033] Figure 10This is a structural diagram of the gravity balance mechanism of the present invention in an extended state;

[0034] Figure 11 It is a structural schematic diagram of the guide block of the present invention;

[0035] Figure 12 for Figure 11 A schematic diagram of the structure of the relative angles of the middle guide block;

[0036] Figure 13 A simplified diagram of the telescopic arm assembly of the present invention during its extension and retraction process;

[0037] Figure 14 This is a schematic diagram of the balancing force without considering friction in Example 1 of the present invention;

[0038] Figure 15 for Figure 14 The vertical axis enlarged graph;

[0039] Figure 16 This is a schematic diagram of the balancing force in consideration of friction in Example 1 of the present invention;

[0040] Figure 17 for Figure 16 The vertical axis enlarged graph;

[0041] Figure 18 A simplified diagram showing that the direction of the spring force and the force of the output slider are not perpendicular in Example 2 of the present invention;

[0042] Figure 19 This is a structural diagram of a trolley base of the prior art in Example 3 of the present invention;

[0043] Figure numerals: 1. First telescopic arm; 2. Second telescopic arm; 3. Output slider; 4. Elastic member; 5. Base; 6. Fixed hinge; 7. Moving hinge; 8. Guide column; 9. Guide block; 10. Guide rod; 11. First guide hole; 12. Second guide hole; 13. Avoidance groove; 14. Fixed plate; 15. Bearing; 16. Oil-free bushing; 17. Fixed part; 18. First through hole; 19. Second through hole; 20. Spring pin; 21. Constant force spring; 22. Spring mounting seat; 23. Control pedal. DETAILED DESCRIPTION

[0044] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention may be combined accordingly without conflict.

[0045] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. The technical features in the various embodiments of the present invention can be combined accordingly without conflicting with each other.

[0046] In the description of the present invention, it should be understood that when an element is considered to be "connected" to another element, it can be directly connected to the other element or indirectly connected, that is, there are intermediate elements. On the contrary, when an element is said to be "directly" connected to another element, there are no intermediate elements.

[0047] In the description of the present invention, it should be understood that the terms "first" and "second" are used solely for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly specifying the number of technical features being described. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of such features.

[0048] Example 1

[0049] like Figure 1-Figure 5 As shown, a gravity balancing mechanism is assembled between a stationary part and a moving part for balancing the gravity of the moving part, comprising a crank mechanism and an elastic member 4. One end of the crank mechanism and one end of the elastic member 4 are both fixed to the stationary part, and the other end of the elastic member 4 is connected to the input end of the crank mechanism to apply a linearly changing force to the crank mechanism. The output end of the crank mechanism is connected to the moving part. The crank mechanism transmits a linearly changing force so that the output end applies a force to the moving part in the opposite direction to the gravity of the moving part.

[0050] Specifically, the stationary part includes a base 5, combined with Figure 6 and Figure 7As shown, the crank mechanism includes a telescopic arm assembly, one end of an elastic member 4 is fixed to a base 5, and the other end of the elastic member 4 is connected to the input end of the telescopic arm assembly to apply a linearly varying force to the input end. The telescopic arm assembly includes a first telescopic arm 1, a second telescopic arm 2, and an output slider 3. A fixed portion 17 is provided on the base 5. One end of the first telescopic arm 1 is connected to the base 5 via the fixed portion 17 on the base 5 via a fixed hinge 6. The other end of the first telescopic arm 1 is connected to one end of the second telescopic arm 2 via a movable hinge 7. The other end of the second telescopic arm 2 is connected to a moving component. The second telescopic arm 2 is connected to the moving component via the output slider 3, and the second telescopic arm 2 is connected to the output slider 3 via the movable hinge 7. In other words, the first telescopic arm 1, the second telescopic arm 2, and the output slider 3 can all rotate about their respective mounting hinges, while the output slider 3 can only move linearly up and down relative to the base 5. The "fixed" and "movable" terms of the hinge refer to whether its position relative to the base 5 changes.

[0051] Furthermore, the gravity balancing mechanism also includes a guide mechanism, combined with Figure 11 and Figure 12 As shown, the guide mechanism includes a guide column 8, a guide block 9, and a guide rod 10. The guide column 8 is mounted on the base 5 and is sleeved with an elastic member 4. This elastic member 4 is a spring capable of providing a linearly variable force. Specifically, this embodiment uses a conventional compression spring. The guide rod 10 is mounted on the base 5, along which the guide block 9 moves. The guide column 8 and the elastic member 4 are both inserted into the guide block 9. At least one guide rod 10 is provided. The interior of the base 5 is a groove structure, and the guide mechanism is located in the groove. A first through hole 18 and a second through hole 19 are provided on the base 5. A bearing 15 is also provided at the position of the second through hole 19. The bearing 15 is rotatably connected to one end of the first telescopic arm 1. A first guide hole 11 and at least one second guide hole 12 are provided on the guide block 9. The guide column 8 extends from the outside of the base 5 through the first through hole 18 to the inside of the groove until it is inserted into the first guide hole 11. One end of the guide rod 10 is fixed to one side of the base 5, and the other end of the guide rod 10 passes through the second guide hole 12 and is fixed to the other side of the base 5 through a fixing plate 14. An oil-free bushing 16 is also provided on the guide rod 10. The oil-free bushing 16 is located in the second guide hole 12. Through the oil-free bushing 16, the guide block 9 can slide smoothly in the base 5 along at least one guide rod 10. A avoidance groove 13 is also provided at the bottom of the guide block 9, and the crank mechanism moves below the avoidance groove 13. The avoidance groove 13 is provided to reduce the weight of the gravity balancing mechanism itself on the one hand, and to facilitate the crank mechanism to be accommodated in the avoidance groove 13 when it is retracted, thereby avoiding unnecessary interference between the crank mechanism and the bottom of the guide block 9 when it is retracted, thereby reducing the height dimension of the entire mechanism.

[0052] Specifically, the working principle of the gravity balance mechanism is: combined with Figures 8-10 As shown, the force generated by the compressed spring pushes the guide block 9, causing it to press against the end of the first telescopic arm 1 mounted with the bearing 15. At this point, the spring imparts a rotational torque to the first telescopic arm 1, which, through the crank mechanism, drives the output slider 3 upward, ensuring that the output slider 3 consistently exerts an upward pulling force. By using an appropriate rod length, the output slider 3 can maintain a nearly constant upward pulling force throughout its entire travel range.

[0053] Specifically, combined Figure 13 As shown, when designing and calculating the rod length, auxiliary software such as Metalab can be used to perform force analysis and fitting calculations on the crank mechanism and spring. For example, if the output slider 3 is required to provide an approximately constant force F, the tension is applied to the end of the output slider 3. At this time, the force analysis of the crank mechanism is performed, and the expression f(F) for the torque applied to the first telescopic arm 1 by the force is listed. At the same time, a more suitable standard compression spring is selected, and the expression f(spring) for the torque applied by the spring to the first telescopic arm 1 is listed. The calculation involves several parameters, such as the main rod length L1 of the first telescopic arm 1, the main rod length L2 of the second telescopic arm 2, the length L3 of one end of the clamping guide block 9 in the first telescopic arm 1, the rod length L3 of the clamping guide block 9 in the first telescopic arm 1, the angle θ between the rod and the perpendicular line of the main rod length L1 of the first telescopic arm 1, and the installation position S of the spring on the base 5. During design, these five values ​​can be used as independent variables to programmatically calculate the absolute value of the difference between f(F) and f(spring) within the full range of travel to minimize it, thereby determining the rod length and spring installation position of each telescopic arm. Of course, the entire analysis and calculation involves more parameters than those listed above. Those skilled in the art will appreciate that other values ​​can also be used as independent variables to perform the analysis and calculation based on structural design needs.

[0054] Specifically, combined Figure 13As shown, when the spring expands and contracts horizontally, the elastic force it provides varies linearly. To ensure that the tension applied to the output slider 3 is approximately constant, specific parameters such as rod length and angle are designed. When the given input parameters vary, the resulting structure will also change, and is not limited to the configurations listed in this embodiment. After the spring is selected, the configuration presented in this embodiment is based on the following input parameters: the distance T from the spring end to the surface of the bearing 15, the diameter D of the bearing 15, Y (the vertical distance between the center of the dynamic hinge 7 on the output slider 3 and the center of the fixed hinge 6 within the full travel range, which can also be understood as the initial position Y1 and the end position Y2), and LX (the horizontal distance between the two). The remaining five parameters are calculated: the main rod length L2 of the second telescopic arm 2, the main rod length L1 of the first telescopic arm 1, the length L3 of one end of the pressing guide block 9 in the first telescopic arm 1, the angle θ between the vertical line of the main rod length L1 of the first telescopic arm 1, and the spring installation position S on the base 5. The horizontal distance from the spring's head end to the center of the fixed hinge 6 represents the spring installation position. The error of the result obtained in this embodiment is within 5%, which can meet the needs of gravity balance. Generally, those skilled in the art will first complete the spring selection, and then use at least Y and LX as input parameters. Of course, the characteristics of the spring can also be used as the calculation quantity, but this may occur in existing products on the market. It is impossible to select a spring with the calculated characteristics, and customization is required, thereby increasing the cost of the equipment. Combined with Figure 14-17 As shown, Figure 14 This is a schematic diagram of the balancing force without considering friction in Example 1 of the present invention; Figure 15 for Figure 14 The vertical axis enlarged graph; Figure 16 This is a schematic diagram of the balancing force in consideration of friction in Example 1 of the present invention; Figure 17 for Figure 16 The vertical axis enlarged diagram; set the expected balance force to 18kgf, through Figure 14 and Figure 15 As can be seen, when balancing force is not considered, the figure shows a range of 17.9kgf to 18.1kgf. Compared to the desired 18kgf, the error is very small, only 0.55%, which meets the requirements. When balancing force is considered for reciprocating motion, the figure shows a range of 17.6kgf to 18.4kgf, with an error of 2.2%, which also meets the requirements.

[0055] Example 2

[0056] Different from Example 1, Figure 18As shown, the relative directions of the spring force and the force of the output slider 3 in this embodiment are no longer perpendicular, and can be parallel, for example. Of course, any other angle is possible, as long as space permits. The spring applies a downward force, which, through the conversion of the telescopic arm, will provide an upward force to the output slider 3. It will be understood that this embodiment is an exemplary illustration of the positional relationship between the spring force and the output slider, and is not limited to perpendicular or parallel relationships. Of course, the crank mechanism is not limited to having only two telescopic arms, but the structure of two telescopic arms is the simplest, and the analysis and fitting calculations are also simple.

[0057] Example 3

[0058] Based on the gravity balance mechanism of embodiment 1, different from Figure 19 The schematic diagram of the structure of a conventional trolley base is shown. A trolley base is implemented, wherein the stationary component includes a base frame, which is mounted on the trolley base, and a gravity balancing mechanism. The moving component includes a control pedal 23, which is mounted on the trolley base. This trolley base has the same technical effects as Example 1.

[0059] Example 4

[0060] Based on the trolley base of Example 3, a surgical robot is implemented, which also has the same technical effects as Example 3.

[0061] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A gravity balancing mechanism for a doctor's trolley base, mounted between the base frame and the control pedal of the doctor's trolley base, for balancing the gravity of the control pedal, characterized in that: The crank mechanism comprises a crank mechanism and an elastic member, one end of the crank mechanism and one end of the elastic member are both fixed to the base frame, the other end of the elastic member is connected to the input end of the crank mechanism to apply a linearly varying force to the crank mechanism, and the output end of the crank mechanism is connected to the control pedal. The crank mechanism transmits the linearly varying force so that the output end applies a substantially constant force to the control pedal in the opposite direction of the gravity of the control pedal, wherein substantially constant means that the fluctuation amplitude is ≤5% within the full stroke range of the crank mechanism; The base frame includes a base, the crank mechanism includes a telescopic arm assembly, one end of the elastic member is fixed to the base, and the other end of the elastic member is connected to the input end of the telescopic arm assembly to apply a linearly changing force to the input end; The telescopic arm assembly includes a first telescopic arm and a second telescopic arm, one end of the first telescopic arm is connected to the base through a fixed hinge, the other end of the first telescopic arm is connected to one end of the second telescopic arm through a movable hinge, and the other end of the second telescopic arm is connected to the moving component; Wherein, the crank mechanism further includes an output slider, the second telescopic arm is connected to the control pedal via the output slider, and the second telescopic arm and the output slider are connected via a movable hinge.

2. The gravity balancing mechanism of the doctor's trolley base according to claim 1, characterized in that: The base is provided with a fixing portion, and the first telescopic arm is connected to the base via the fixing portion.

3. The gravity balancing mechanism of the doctor's trolley base according to claim 1, characterized in that: The utility model also comprises a guide mechanism, which comprises a guide column installed on the base and an elastic member sleeved on the guide column.

4. The gravity balancing mechanism of the doctor's trolley base according to claim 3 is characterized in that: The guide mechanism further comprises a guide block and a guide rod, the guide rod is mounted on the base, the guide block moves along the guide rod, and the guide column and the elastic member are inserted into the guide block together.

5. The gravity balancing mechanism of the doctor's trolley base according to claim 3, characterized in that: The interior of the base is a groove structure, the guide mechanism is located in the groove, and a first through hole is opened on the base, a first guide hole is opened on the guide block, and the guide column extends from the outside of the base through the first through hole to the inside of the groove until it is inserted into the first guide hole.

6. The gravity balancing mechanism of the doctor's trolley base according to claim 3, characterized in that: The base is further provided with a second through hole, one end of the first telescopic arm is connected to a bearing, and the bearing is located in the second through hole.

7. The gravity balancing mechanism of the doctor's trolley base according to claim 4, characterized in that: The bottom of the guide block is also provided with an avoidance groove, and the crank mechanism moves below the avoidance groove.

8. The gravity balancing mechanism of the doctor's trolley base according to claim 4, characterized in that: The guide block is further provided with at least one second guide hole. One end of the guide rod is fixed to one side surface of the base, and the other end of the guide rod passes through the second guide hole and is fixed to the other side surface of the base.

9. The gravity balancing mechanism of the doctor's trolley base according to claim 8, characterized in that: An oil-free bushing is also sleeved on the guide rod, and the oil-free bushing is located in the second guide hole.

10. The gravity balancing mechanism of the doctor's trolley base according to claim 1, characterized in that: The elastic member is a spring that provides a linearly changing force.

11. A surgical robot, characterized in that: The invention comprises a gravity balancing mechanism of the doctor's trolley base as described in any one of claims 1-10.

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