CN214699048U

CN214699048U - Medical instrument

Info

Publication number: CN214699048U
Application number: CN202120685284.8U
Authority: CN
Inventors: 王雨溥
Original assignee: Agile Medical Technology Suzhou Co ltd
Current assignee: Agile Medical Technology Suzhou Co ltd
Priority date: 2021-04-02
Filing date: 2021-04-02
Publication date: 2021-11-12
Anticipated expiration: 2031-04-02

Abstract

The utility model discloses a medical instrument, relating to the medical technical field, comprising an executor, a driving unit, a hollow transmission rod, an upper fixed plate and a lower fixed plate; the driving unit comprises a screw rod, a nut, a guide piece and a driving piece, wherein the nut is provided with a transmission hole and a guide hole, the transmission hole is in transmission fit with the screw rod, and the guide piece is in clearance fit with the guide hole in the nut; the screw rod and the two ends of the guide piece are respectively connected with the upper fixing plate and the lower fixing plate, the upper end of the driving piece is connected with the nut, the lower end of the driving piece extends into the hollow transmission rod and is connected with the actuator after passing through the hollow transmission rod, and the central axis of the driving piece in the hollow transmission rod is parallel to the central axis of the hollow transmission rod. The utility model discloses a mechanism is more compact, and the leading wheel subassembly more saves space in the vertical direction distribution.

Description

Medical instrument

Technical Field

The utility model belongs to the technical field of the medical treatment technique and specifically relates to a medical instrument is related to.

Background

Surgical robots assist in minimally invasive surgery and are becoming mature and widely used. During the operation of the surgical robot, a doctor sends an instruction through the master control end, the multiple mechanical arms at the slave end are operated to cooperate with each other to complete the surgery at a specified position, the instrument power box is arranged on the mechanical arm at the slave end, one end of the instrument power box is connected to the mechanical arm, and the other end of the instrument power box is connected to the actuator. The instrument power box is used as a driven end driving mechanism of the surgical robot to drive an executing mechanism, and is matched with different instructions sent by medical staff at a main control end to complete various actions or postures, such as pitching, rotating, deflecting/clamping and the like. And when the number of arms of the existing surgical robot is large, such as four or more, the size of the instrument power box is larger, the movement space of the opposite arm is smaller, and the movement range is limited.

Chinese patent CN106109019B provides an instrument box and surgical instruments, the instrument box includes a turnover table component, two groups of driving wires, two wire rotating bodies and four output wires, each group of driving wires includes two driving wires, two fixed points formed on the rotating component of each group of driving wires are symmetrical about a first intersection point, four fixed points formed on the rotating component of the four driving wires are sequentially connected to form a first parallelogram, the intersection point of the diagonal line of the first parallelogram is the first intersection point, the other ends of the two driving wires in each group of driving wires are wound on the corresponding wire rotating bodies in opposite directions, thereby the turnover table component is driven to move based on the four driving wires, then the output wires transmit the motion of the turnover table component to the terminal instrument component, so that the terminal instrument component realizes the motion in multiple directions and multiple degrees of freedom, and the design of the instrument box is simplified, the volume of the instrument box is reduced, and the space utilization rate of the instrument box is improved.

Chinese patent CN105286999B discloses a minimally invasive surgical instrument with terminal rotation function, which comprises an instrument terminal and an instrument box, wherein the instrument terminal comprises an opening and closing component, the opening and closing component comprises left and right opening and closing forceps, the left and right opening and closing forceps are rotatably mounted on a terminal self-rotating seat through a support shaft, the terminal self-rotating seat is rotatably mounted on a deflection base, the terminal self-rotating seat is connected with a rotation driving device, a deflection wheel is fixed on the deflection base, the front end of a terminal support is rotatably connected on the deflection base through a rotating shaft of the deflection wheel to connect the front end of a long shaft with the terminal support, the rear end of the long shaft is fixedly connected with a rotating shaft of the instrument box, an opening and closing transmission device, a terminal rotation transmission device, a deflection transmission device and a rotation transmission device are arranged in the instrument box. The device adopts a novel four-degree-of-freedom layout form, and can effectively reduce the difficulty of the robot in the operation operations such as suturing and knotting besides higher flexibility.

Chinese patent CN102171006B discloses an automated medical system that utilizes a passive preload system connected to a tendon wrapped around a capstan to control the tension of slack in the tendon. The passive preload system can utilize springs or other structures to apply tension to the tendons. The capstan may be motor driven when the tendon is required to pull on a structural member of the instrument. For example, to apply a clamping pressure or move the structural member against a resistive force, capstan friction can generate tendon tension many times that applied by the passive preload system. But when the tendon is not required to apply force to the member, the capstan can be released so that the spring system provides sufficient tension to prevent the tendon from moving laterally or otherwise failing in operation. A small tension in a relaxed tendon can reduce tendon friction, particularly in instruments with a flexible shaft.

The above-mentioned published patents all relate to the technical field of medical instruments, wherein the CN106109019B patent adopts a steel wire rope as a driving wire, and a guide wheel corresponds to a driving wire, the motion of a plurality of output wires and a terminal instrument component connected with the output wires is controlled by a turnover table component connected with the driving wire, the turnover table is composed of rotating parts, the structure is complex, and disorder is easy to occur; although the steel wire rope in the patent CN105286999B is arranged on the wire fixing mechanism, the wire fixing mechanism is connected with the tail end rotation transmission device, and the guide wheel of the invention is arranged on the rotating shaft, so that the occupied space is large; the CN102171006B patent is mainly fixed to the reel through a tendon (mentioned in CN 102171006) at one end and extends to the actuator end through an elongated rod at the other end; different motors drive different reel wheels to rotate, so that the cables can be shortened or lengthened, and the actions or postures of pitching, rotating and the like of the executing mechanism can be completed. Although the scheme is widely applied, the winch and various guide wheels are distributed on the same horizontal plane, so that the power box of the instrument is flat, and the length and width directions of the power box are larger, so that the size of the power box of the instrument is larger. In summary, the above technical problems still exist in the prior art.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides a medical instrument.

In order to realize the utility model discloses a purpose, the utility model discloses a technical scheme as follows:

a medical instrument comprises an actuator, a driving unit, a hollow transmission rod, an upper fixing plate and a lower fixing plate; the driving unit comprises a screw rod, a nut, a guide piece and a driving piece, wherein the nut is provided with a transmission hole and a guide hole, the transmission hole is in transmission fit with the screw rod, and the guide piece is in clearance fit with the guide hole in the nut; the screw rod and the two ends of the guide piece are respectively connected with the upper fixing plate and the lower fixing plate, the upper end of the driving piece is connected with the nut, the lower end of the driving piece extends into the hollow transmission rod and is connected with the actuator after passing through the hollow transmission rod, and the central axis of the driving piece in the hollow transmission rod is parallel to the central axis of the hollow transmission rod.

Further, the device also comprises at least one swing actuator, wherein the swing actuator is installed between the upper fixing plate and the lower fixing plate; the swing actuator includes the driving unit; the actuator includes a swing assembly; the tail end of a driving piece of the driving unit penetrates through the hollow transmission rod and then is connected with the swinging assembly.

Further, the device also comprises at least one pitching actuator, wherein the pitching actuator is installed between the upper fixing plate and the lower fixing plate; the pitch actuator comprises the drive unit; the actuator includes a pitch assembly; the tail end of a driving piece of the driving unit penetrates through the hollow transmission rod and then is connected with the pitching assembly.

The upper fixing plate is fixed on the lower fixing plate, the lower fixing plate is fixed on the lower fixing plate, the upper end of the hollow transmission rod is inserted into the lower fixing plate, the upper end of the hollow transmission rod is connected with the rotary actuator, and the lower end of the hollow transmission rod is connected with the actuator.

Furthermore, the driving part is a cable, the cable comprises a first cable and a second cable which move in opposite directions, the head ends of the first cable and the second cable are connected with the nut, the tail end of the cable is introduced into the hollow transmission rod of the actuator, and the central axis of the cable is parallel to the central axis of the hollow transmission rod; the cable in the swing actuator is wound on the swing assembly, and the cable in the pitching actuator is wound on the pitching assembly.

Further, the driving unit further comprises an upper guide wheel assembly and a lower guide wheel assembly, the upper guide wheel assembly is fixed above the nut, and the lower guide wheel assembly is fixed below the nut; the first cable is wound on the upper guide wheel assembly, and the second cable is wound on the lower guide wheel assembly.

Further, the driving member is a rigid rod.

Furthermore, the rotary actuator comprises a main transmission shaft, a driving gear and a driven gear, the driven gear is sleeved at the upper end of the hollow transmission rod, the driving gear is mounted on the main transmission shaft and meshed with the driving gear, and the driving gear and the driven gear are both mounted on the lower fixing plate; the upper end of the main transmission shaft is fixedly connected with the upper fixing plate through a supporting bearing, and the inner ring at the upper end of the supporting bearing is provided with a limiting clamp spring.

Furthermore, a limiting component is arranged on the driven gear and used for limiting the driven gear to move.

Furthermore, the limiting component straddles on the driven gear, two ends of the limiting component extend downwards to be connected with the lower fixing plate respectively, a through hole is formed in the middle of the limiting component, the through hole is coaxial with the hollow transmission rod, and the through hole is sleeved on the hollow transmission rod.

Further, the driving members are evenly arranged within the hollow driving rod.

Compared with the prior art, the beneficial effects of the utility model are embodied in that:

(1) compared with a winch mechanism, the utility model is driven by a screw rod or a thread mechanism, the driving shaft mechanism is more compact, and the guide wheels are distributed in the vertical direction to save more space;

(2) the utility model adopts the motor to drive the screw rod or the thread, thereby realizing more accurate transmission;

(3) the utility model can also utilize the self-locking performance of the screw rod or the thread, and the actuator can still keep the original posture under the condition of power failure of the motor;

(4) the utility model discloses a power transmission mode is not restricted to the cable, can also adopt rigid rod drive executor.

Drawings

FIG. 1 is a schematic structural view of a medical device of the present application;

FIG. 2 is a schematic view of a portion of the medical device of the present application;

FIG. 3 is a schematic view of the device shown in FIG. 2 without the mounting plate;

FIG. 4 is a schematic view of a rotary actuator;

fig. 5 is a schematic structural view of a swing actuator in embodiment 1;

FIG. 6 is a distribution diagram of a plurality of cables in the hollow transmission rod of the embodiment 1;

FIG. 7 is a schematic structural view of the medical device according to embodiment 2, wherein the guide member is a rigid rod;

the reference numbers are as follows: 1. an upper fixing plate; 2. a hollow transmission rod; 3. an actuator; 4. a screw rod; 5. a nut; 6. a guide member; 7. a drive member; 71. a first cable; 72. a second cable; 73. a rigid rod; 8. a main drive shaft; 9. a driving gear; 10. a driven gear; 12. a lower fixing plate; 13. a swing actuator; 14. a pitch actuator; 15. a limiting component; 16. an upper guide wheel assembly; 161. a first guide wheel; 162. a second guide wheel; 17. a lower guide wheel assembly; 171. a third guide wheel; 172. and a fourth guide wheel.

Detailed Description

In order to make the objects and technical solutions of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the following embodiments.

Example 1

1-6, a medical instrument comprising an actuator 3, a drive unit, a hollow transmission rod 2, an upper fixed plate 1 and a lower fixed plate 12; the drive unit comprises a screw 4, a nut 5, a guide 6 and a drive 7. The nut 5 is provided with a transmission hole and a guide hole, the transmission hole is in transmission fit with the screw rod 4, and the guide piece 6 is in clearance fit with the guide hole on the nut 5 and used for limiting the rotational freedom degree of the nut 5; the lead screw 4 with the both ends of guide 6 respectively with upper fixed plate 1 and bottom plate 12 link to each other, and wherein the tip is fixed on bottom plate 12 under the lead screw 4, and the upper end of lead screw 4 is connected with upper fixed plate 1, and guide 6 sets up between bottom plate 12 and upper fixed plate 1 and the lower extreme of guide 6 is fixed on bottom plate 12, supports through guide 6 between bottom plate 12 and the upper fixed plate 1, guarantees the relative position relation between upper fixed plate 1 and the bottom plate 12. The upper end of the driving piece 7 is connected with the nut 5 through the fixing part, the lower end of the driving piece 7 extends into the hollow transmission rod 2 to the end of the actuator 3 and is connected with the actuator 3, and the central axis of the driving piece 7 in the hollow transmission rod 2 is parallel to the central axis of the hollow transmission rod 2. The driving elements 7 are arranged uniformly within the hollow driving rod 2. As shown in fig. 3, the guide 6 is cylindrical, the guide 6 is located on one side of the screw 4, and the guide 6 is engaged with the nut 5. The guide piece 6 can also be a trapezoid rod or a rod with a limit groove along the vertical direction; the present embodiment does not limit the specific shape of the guide bar 6 as long as the guide bar can limit the rotation of the nut 5.

1-6, further comprising at least one oscillation actuator 13, said oscillation actuator 13 being mounted between said upper and lower fixed

plates

1, 12; the swing actuator 13 includes the driving unit; the actuator 3 comprises a swing assembly; the tail end of a driving piece 7 of the driving unit penetrates through the hollow transmission rod 2 and then is connected with the swinging component.

The medical device of the present embodiment further comprises at least one pitch actuator 14, wherein the pitch actuator 14 is installed between the upper fixing plate 1 and the lower fixing plate 12; the pitch actuator 14 includes the driving unit; the actuator 3 comprises a pitch assembly; the tail end of a driving part 7 of the driving unit penetrates through the hollow transmission rod 2 and then is connected with the pitching assembly.

The medical instrument of the present embodiment further comprises a rotary actuator, the rotary actuator is installed between the upper fixing plate 1 and the lower fixing plate 12, the upper end of the hollow transmission rod 2 is inserted into the lower fixing plate 12, the upper end of the hollow transmission rod 2 is connected with the rotary actuator, and the lower end of the hollow transmission rod 2 is connected with the actuator 3.

Specifically, the medical device of the present application may include only one pitch actuator 14, one roll actuator 13, one pitch actuator 14 and one roll actuator 13, or one pitch actuator 14, one roll actuator 13 and one rotation actuator, and the like, which are all within the protection scope of the present application and can be set according to actual requirements.

As shown in fig. 2 and 3, the swing actuator 13 is provided in two, and the pitch actuator 14 is provided in one.

As shown in fig. 2 to 6, the driver 7 is provided as a cable, and the driver 7 of the swing actuator 13 includes a first cable 71 and a second cable 72; the head ends of a first cable 71 and a second cable 72 in the swing actuator 13 are respectively fixed on the nut 5 through a fixing part, and the tail ends of the cables are respectively led into the hollow transmission rod 2; the first cable 71 and the second cable 72 in the swing actuator 13 are driven by the nut 5 to perform reverse linear motion; the head ends of the cables in the pitch actuators 14 are respectively fixed on the nuts 5 through fixing parts, and the tail ends of the cables are all led into the hollow transmission rod 2; the cable in the pitching actuator 14 is driven by the nut 5 to perform reverse linear motion; the central axes of the first and second cables 71 and 72 of the swing actuator 13 and the central axis of the cable of the pitch actuator 14 extending into the hollow transmission rod 2 are parallel to the central axis of the hollow transmission rod 2; the first cable 71 and the second cable 72 of the roll actuator 13 are wound around the roll assembly, and the cables of the pitch actuator 14 are wound around the pitch assembly.

The driving unit further comprises an upper guide wheel assembly 16 and a lower guide wheel assembly 17, the upper guide wheel assembly 16 and the lower guide wheel assembly 17 are distributed in the vertical direction, the upper guide wheel assembly 16 is fixed above the nut 5 through a fixed base, and the lower guide wheel assembly 17 is fixed below the nut 5 through a fixed base; the first cable 71 is wound around the upper guide wheel assembly 16, and the second cable 72 is wound around the lower guide wheel assembly 17. The upper guide wheel assembly 16 and the lower guide wheel assembly 17 are arranged, so that firstly, in the wire winding and wire unwinding processes, cables between the upper guide wheel assembly 16 and the nut 5 and between the lower guide wheel assembly 17 and the nut 5 can be parallel to the axis of the screw rod 4, and secondly, the central axis of the cable extending into the hollow transmission rod 2 is always parallel to the central axis of the hollow transmission rod 2. Specifically, two fixing bases are fixed above and below the nut 5 by means of screws and the like, each fixing base comprises two fixing panels arranged in parallel, the upper guide wheel assembly 16 can be installed between the two fixing panels by means of screws and the like, and the lower guide wheel assembly 17 is also installed between the two fixing panels by means of screws and the like.

The rotary actuator comprises a main transmission shaft 8, a driving gear 9 and a driven gear 10, the driven gear 10 is sleeved at the upper end of the hollow transmission rod 2, a supporting bearing is arranged at the joint of the driven gear 10 and the hollow transmission rod 2 and used for realizing the self-use rotation of the driven gear 10 and the hollow transmission rod 2, the driving gear 9 is installed on the main transmission shaft 8, the driving gear 9 is meshed with the driven gear 10, and the driving gear 9 and the main transmission shaft 8 are installed on a lower fixing plate 12 through the supporting bearing respectively; the upper end of the main transmission shaft 8 is fixedly connected with the upper fixing plate 1 through a supporting bearing, a limiting snap spring is installed on an inner ring at the upper end of the supporting bearing, and an outer ring at the lower end of the supporting bearing is fixedly connected with the upper fixing plate 1.

The lower fixing plate 12 is further provided with a limiting part 15, preferably, the limiting part 15 straddles over the driven gear 10 and is used for limiting the horizontal movement or the longitudinal movement of the driven gear 10, two ends of the limiting part 15 respectively extend downwards until being connected with the lower fixing plate 12, a through hole is further formed in the middle of the limiting part 15, and the through hole is coaxial with the hollow transmission rod 2 and is sleeved on the hollow transmission rod 2.

Description of the working principle of a medical device according to the type shown in fig. 1-6: the main transmission shaft 8 rotates to drive the driving gear 9 to rotate, the driving gear 9 rotates to further drive the driven gear 10 meshed with the driving gear to rotate, the driven gear 10 rotates to drive the hollow transmission rod 2 to rotate, and the hollow transmission rod 2 rotates to further drive the actuator 3 to complete rotation.

As shown in fig. 5, the upper guide wheel assembly 16 on the swing actuator 13 includes a first guide wheel 161 and a second guide wheel 162, the lower guide wheel assembly 17 includes a third guide wheel 171 and a fourth guide wheel 172, the first cable 71 in the swing actuator 13 first bypasses the first guide wheel 161 and then bypasses the second guide wheel 162 in parallel with the axis of the screw rod 4, and the first cable 71 passing through the second guide wheel 162 is always parallel with the central axis direction of the hollow transmission rod 2 until extending to be connected with the swing assembly on the actuator 3; the second cable 72 firstly downwardly bypasses the fourth guide wheel 172 and then bypasses the third guide wheel 171 in parallel with the axis of the screw rod 4, the second cable 72 after passing through the third guide wheel 171 is always parallel with the axis direction of the hollow transmission rod 2 until extending to be connected with the swinging component on the actuator 3, wherein the tail end of the first cable 71 and the tail end of the second cable 72 are connected to different sides of the same swinging component on the actuator 3.

The principle of movement of the upper and lower

guide wheel assemblies

16, 17 on pitch actuator 14 is the same as the principle of movement of the upper and lower

guide wheel assemblies

16, 17 of roll actuator 13, i.e. the cables in pitch actuator 14 are connected to different sides of the same pitch assembly on implement 3.

The screw 4 in the swing actuator 13 rotates to drive the nut 5 coupled with the screw 4 to move, the nut 5 is matched with the guide piece 6, and the guide piece 6 limits the nut 5 to only move up and down but not rotate around the screw 4. When the screw rod 4 rotates to drive the nut 5 to move upwards, the swing assembly on the actuator 3 is pulled to move towards one direction through the second cable 72, and meanwhile, the first cable 71 releases part of the first cable 71, so that the swing of the swing assembly is not subjected to resistance generated by the first cable 71; when the nut 5 is driven by the rotation of the screw rod 4 to move downwards, the swing assembly is pulled to move towards the other direction through the first cable 71, and meanwhile, the second cable 72 releases part of the second cable 72, so that the swing of the swing assembly cannot be subjected to the resistance action generated by the second cable 72, and the actions of deflection, clamping and the like of the swing assembly at the end of the actuator 3 are realized.

The movement principle of the driving unit of the pitch actuator 14 is the same as that of the driving unit in the swing actuator 13, and under the action of the driving unit, the cable in the pitch actuator 14 drives the pitch component to move, that is, the pitch motion of the pitch component at the end of the actuator 3 is realized.

Example 2

As shown in fig. 7, unlike the present embodiment 1, the driving member 7 of the present embodiment is a rigid rod 73,

one end of a rigid rod 73 in the swing actuator 13 is connected with the nut 5 in the swing actuator 13, and the other end of the rigid rod 73 is connected with a swing assembly at the end of the actuator 3. In particular, the upper end of the rigid rod 73 is rigidly connected to the nut 5 by welding or other rigid connection means

When the screw rod 4 in the swing actuator 13 rotates to drive the nut 5 to move upwards, the rigid rod 73 drives the swing assembly at the end of the actuator 3 to move towards one direction, and when the screw rod 4 drives the nut 5 to move downwards, the rigid rod 73 drives the swing assembly at the end of the actuator 3 to move towards the other direction, so that the swinging, tightening and other actions of the swing assembly at the end of the actuator 3 are realized.

The movement principle of the rigid rod 73 in the pitch actuator 14 is the same as that of the rigid rod 73 in the roll actuator 13, and the pitching action of the pitch component at the end of the actuator 3 is realized.

The above description is only for the embodiments of the present invention, and the description is specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several changes and modifications can be made, which all fall within the scope of the present invention.

Claims

1. A medical instrument is characterized by comprising an actuator, a driving unit, a hollow transmission rod, an upper fixing plate and a lower fixing plate; the driving unit comprises a screw rod, a nut, a guide piece and a driving piece, wherein the nut is provided with a transmission hole and a guide hole, the transmission hole is in transmission fit with the screw rod, and the guide piece is in clearance fit with the guide hole in the nut; the screw rod and the two ends of the guide piece are respectively connected with the upper fixing plate and the lower fixing plate, the upper end of the driving piece is connected with the nut, the lower end of the driving piece extends into the hollow transmission rod and is connected with the actuator after passing through the hollow transmission rod, and the central axis of the driving piece in the hollow transmission rod is parallel to the central axis of the hollow transmission rod.

2. The medical device of claim 1, further comprising at least one oscillation actuator mounted between said upper and lower fixed plates; the swing actuator includes one of the driving units; the actuator includes a swing assembly; the tail end of a driving piece of the driving unit penetrates through the hollow transmission rod and then is connected with the swinging assembly.

3. The medical instrument of claim 2, further comprising at least one pitch actuator mounted between the upper and lower fixed plates; said pitch actuator comprises one said drive unit; the actuator includes a pitch assembly; the tail end of a driving piece of the driving unit penetrates through the hollow transmission rod and then is connected with the pitching assembly.

4. The medical instrument of claim 3, further comprising a rotary actuator mounted between the upper and lower fixed plates, wherein the upper end of the hollow drive rod is inserted into the lower fixed plate, and wherein the upper end of the hollow drive rod is connected to the rotary actuator and the lower end of the hollow drive rod is connected to the actuator.

5. The medical instrument of claim 4, wherein the driving member is a cable, the cable includes a first cable and a second cable with opposite movement directions, the head ends of the first cable and the second cable are connected to the nut, and the tail ends of the cables are introduced into the hollow transmission rod of the actuator, and the central axis of the cables is parallel to the central axis of the hollow transmission rod; the cable in the swing actuator is wound on the swing assembly, and the cable in the pitching actuator is wound on the pitching assembly.

6. The medical device of claim 5, wherein said drive unit further comprises an upper guide wheel assembly and a lower guide wheel assembly, said upper guide wheel assembly being secured above said nut and said lower guide wheel assembly being secured below said nut; the first cable is wound on the upper guide wheel assembly, and the second cable is wound on the lower guide wheel assembly.

7. The medical device of claim 1, wherein the driving member is a rigid rod.

8. The medical apparatus according to claim 4, wherein the rotary actuator comprises a main transmission shaft, a driving gear and a driven gear, the driven gear is sleeved on the upper end of the hollow transmission rod, the driving gear is mounted on the main transmission shaft, the driving gear and the driven gear are meshed, and the driving gear and the driven gear are both mounted on the lower fixing plate; the upper end of the main transmission shaft is fixedly connected with the upper fixing plate through a supporting bearing, and the inner ring at the upper end of the supporting bearing is provided with a limiting clamp spring.

9. The medical instrument as claimed in claim 8, wherein the driven gear is provided with a limiting member for limiting the movement of the driven gear.

10. The medical apparatus as claimed in claim 9, wherein the position-limiting member straddles the driven gear, and both ends of the position-limiting member extend downward to connect with the lower fixing plate, respectively, and a through hole is formed in the middle of the position-limiting member, the through hole is coaxial with the hollow transmission rod, and the through hole is sleeved on the hollow transmission rod.

11. A medical device according to claim 10, wherein the driving members are arranged uniformly within the hollow driving rod.