Myopic surgery with negative pressure suction ring capable of precisely regulating adsorption force and method of using the same

Abstract

The application belongs to the technical field of negative pressure suction rings and relates to a myopia surgery negative pressure suction ring capable of precisely regulating suction force and a use method thereof. The negative pressure suction ring comprises an upper ring shell, a clamping fixing assembly and a lifting adjusting assembly. The clamping fixing assembly is connected to a connecting port, the suction ring can be quickly installed on a full-femtosecond surgery machine, the surgery treatment efficiency is accelerated, and the workload of medical staff is saved. Then, an air suction port is connected to a negative pressure suction port, and an air outlet is connected to an air bag air inlet. The sealed air bag can be inflated to seal the suction ring and the connecting port. The negative pressure suction port can form a negative pressure in the suction ring to suck the eyeball of a patient, thereby facilitating full-femtosecond surgery treatment. When the clamping fixing assembly is started, the lifting adjusting assembly can be started. The lower ring shell can be driven to move up and down along the screw rod by the lifting adjusting assembly, thereby achieving the effect of precise regulation and increasing the applicability of surgery and the practicality of the suction ring.

Description

Technical Field

[0001] This invention belongs to the field of negative pressure suction ring technology, and particularly relates to a negative pressure suction ring for myopia surgery with precisely adjustable adsorption force and its usage method. Background Technology

[0002] From initially simply wanting to get rid of glasses, to the hope of improving eyesight, and finally to the ultimate goal of improving overall visual quality and enhancing quality of life, people's pursuits have undergone tremendous changes. People have begun to hope for good vision at all distances, that is, clear vision at near, intermediate, and far distances; and they hope to have good vision in all weather conditions, that is, good visual quality in various brightness and contrast environments; and they also hope to have suitable visual quality for most of their lives.

[0003] A search revealed that application number CN201020244868.3 discloses a negative pressure suction ring for corneal refractive surgery. The ring includes a negative pressure suction ring body, two blade tracks on both sides of the upper surface of the ring body, a negative pressure suction tube and a blade drive nut tube on the end face of the ring body. The ring body has two interconnected perforations, one larger at the bottom and one smaller at the top. The larger perforation at the bottom forms the outer suction ring, and the smaller perforation at the top forms the inner suction ring. Crucially, the inner suction ring is elliptical. This invention effectively prevents pericorneal hemorrhage, reduces surgical risks, and improves postoperative stability.

[0004] The problems with the above technical solutions are as follows: existing negative pressure suction rings are used to fix the eyeball during myopia surgery. However, the existing negative pressure suction rings need to be adjusted and positioned according to the height of the patient's eyeball during use. Moreover, the existing negative pressure suction rings are all one-piece sets and cannot play a self-adjusting role, which reduces the practicality of the negative pressure suction rings. Furthermore, during myopia surgery, they need to be installed on the myopia surgery treatment equipment, and their sealing and fixing methods have certain limitations, which can easily lead to cumbersome installation steps and delay the treatment efficiency. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a negative pressure suction ring for myopia surgery with precisely adjustable adsorption force that can overcome or at least partially solve the above problems, as well as a method of using the ring.

[0006] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by the present invention is as follows: a negative pressure suction ring for myopia surgery with precisely adjustable adsorption force, including an upper ring shell, a clamping and fixing assembly, and a lifting and adjusting assembly. The clamping and fixing assembly includes an upper fixing plate and a lower fixing plate, with the upper fixing plate disposed above the lower fixing plate. The upper and lower fixing plates are provided with a plurality of components fixedly connected to the upper and lower sides of the inner wall of the upper ring shell. A first sliding groove is provided in the middle of the upper fixing plate, and a lifting shaft is installed in the first sliding groove. A connecting bracket is rotatably installed in the middle of the lifting shaft. The lifting and adjusting assembly includes a drive plate, one end of which is rotatably installed on a sliding rod. A groove is provided on one side of the drive plate, and a connecting block is rotatably installed in the groove. One end of the connecting block is fixedly connected to a mounting sheet metal, and a top rod is rotatably installed in the mounting sheet metal.

[0007] Preferably, a sealing airbag is fixedly connected to the upper edge of the upper ring housing, and an air inlet is provided on one side of the sealing airbag. A clamping and fixing assembly is installed inside the upper ring housing, and a lifting and adjusting assembly is installed in cooperation with the clamping and fixing assembly. A lower ring housing is installed on the lifting and adjusting assembly, and a plurality of evenly distributed mounting sleeves are provided on the upper surface of the lower ring housing. A lifting ring is fixedly connected to the lower end of the upper ring housing, and the lifting ring is installed inside the lower ring housing. A connection port is provided above the clamping and fixing assembly, and a pressure plate is fixedly connected to the outer surface of the connection port.

[0008] Preferably, a plurality of evenly distributed sealing protrusions are fixedly connected to the outer surface of the lifting ring, and a sealing mating block is provided on the outer side of the sealing protrusions. The sealing mating block is fixedly connected to the upper edge of the inner wall of the lower ring shell. A connecting ring is fixedly connected to the lower surface of the lower ring shell, and a limit ring is fixedly connected to the inner wall of the connecting ring. A suction nozzle is fixedly connected to the lower surface of the connecting ring, and a negative pressure suction port is provided on one side of the suction nozzle.

[0009] Preferably, a spring push rod is provided at the other end of the connecting bracket, a mounting groove is provided at the lower end of the spring push rod, a spring sleeve is installed in the middle of the spring push rod, the spring sleeve is located at the edge of the upper surface of the upper ring shell, the upper end of the spring push rod is configured to cooperate with the pressure plate, and transmission rods are rotatably installed at both ends of the lifting shaft.

[0010] Preferably, mounting rods are rotatably mounted on the lower ends of the transmission rods on both sides, clamping plates are fixedly connected to the lower ends of the mounting rods on both sides, support rods are rotatably mounted on both sides of the lower ends of the clamping plates, lower fixing plates are rotatably mounted on the lower ends of the support rods on both sides, and a second sliding groove is provided at the lower ends of the support rods on both sides, with a sliding rod installed in the second sliding groove.

[0011] Preferably, a ball is fixedly connected to the other end of the top rod. The ball is installed inside a ball seat, which is fixedly connected to the upper surface of the slider. The slider is installed inside a rotating ring, which is installed inside a slide rail. The slide rail is fixedly connected to the middle of the inner wall of the upper ring housing.

[0012] Preferably, a gear ring is fixedly connected to the outer surface of the rotating ring, and a number of evenly distributed gears are connected to the outer side of the gear ring through meshing. A lead screw is fixedly connected to the lower surface of each gear, and each lead screw is rotatably mounted on the upper ring housing and extends to the lower part of the upper ring housing. A threaded mating rod is threadedly connected to the lower part of each lead screw, and the threaded mating rod is fixedly connected to the mounting sleeve.

[0013] A preferred method for using a negative pressure suction ring for myopia surgery, which allows for precise control of suction force, includes the following steps:

[0014] S1. First, the suction ring is connected to the connection port through the clamping and fixing component, which can quickly install the suction ring on the femtosecond LASIK machine, speeding up the surgical treatment efficiency while saving the workload of medical staff.

[0015] S2. Then connect the inhalation port to the negative pressure suction port, and then connect the outlet port to the air bag inlet. This can make the sealing air bag inflate and seal the suction ring and the connection port. The negative pressure suction port can create negative pressure inside the suction ring, thereby suctioning the patient's eyeball and facilitating the femtosecond LASIK surgery.

[0016] S3. When the clamping and fixing component is activated, the lifting and adjusting component is also activated. The lifting and adjusting component can move the lower ring housing up and down along the screw, thereby achieving precise adjustment, increasing the applicability of the surgery, and improving the practicality of the suction ring.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. This invention, through the clamping and fixing component connected to the connection port, allows for the rapid installation of the suction ring onto the femtosecond LASIK surgical machine, accelerating surgical efficiency while saving the workload of medical staff. Subsequently, the suction port is connected to the negative pressure suction port, and the air outlet is connected to the air inlet of the airbag. This allows the sealing airbag to inflate, sealing the suction ring and the connection port. The negative pressure suction port creates negative pressure inside the suction ring, thereby suctioning the patient's eyeball and facilitating femtosecond LASIK surgery. When the clamping and fixing component is activated, it also activates the lifting and adjusting component. The lifting and adjusting component moves the lower ring shell up and down along the lead screw, achieving precise adjustment, increasing the applicability of the surgery, and improving the practicality of the suction ring.

[0019] 2. In this invention, a spring top rod is installed inside a spring sleeve. When the negative pressure suction ring is fitted into the connection port, the spring top rod contacts the pressure plate and moves downward along the spring sleeve. Through the connecting bracket, the lifting shaft moves up and down in the first slide groove. By rotating the transmission rod and support rod at both ends of the connecting bracket onto the clamping plate, the clamping plate can be moved inward, thereby clamping and fixing the connection port, making it easier to install the negative pressure suction ring onto the approximate surgical treatment machine.

[0020] 3. In this invention, a drive plate is installed on the slide rod on the support rod, and the drive plate pushes the rotating ring to rotate inside the slide rail via the top rod. Since the outer side of the rotating ring is connected to the gear through the gear ring, it can drive the lead screw to rotate. The lead screw is connected to the threaded mating rod through the thread engagement, which can adjust the height between the upper ring shell and the lower ring shell, thereby better achieving the function of fixing the eyeball. Attached Figure Description

[0021] Figure 1 This is a schematic perspective view of the attraction ring connection structure provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic perspective view of the overall structure provided in the embodiment of the present invention;

[0023] Figure 3 This is a partial structural schematic perspective view provided in an embodiment of the present invention;

[0024] Figure 4 This is another partial structural schematic perspective view provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic perspective view of the overall exploded structure provided in an embodiment of the present invention;

[0026] Figure 6 This is a schematic perspective view of the clamping and fixing assembly and the lifting and adjusting assembly provided in the embodiments of the present invention;

[0027] Figure 7 This is a schematic perspective view of the clamping and fixing assembly structure provided in an embodiment of the present invention;

[0028] Figure 8 This is a schematic perspective view of the lifting and adjusting component structure provided in an embodiment of the present invention;

[0029] Figure 9 This is provided by the embodiments of the present invention. Figure 8 Enlarged 3D structural diagram at point a;

[0030] Figure 10 This is provided by the embodiments of the present invention. Figure 8 Enlarged 3D structural diagram at point b.

[0031] In the diagram: 1. Upper ring housing; 2. Sealing airbag; 3. Clamping and fixing assembly; 4. Airbag inlet; 5. Lifting and adjusting assembly; 6. Lower ring housing; 7. Sealing mating block; 8. Lifting ring; 9. Sealing protrusion; 10. Suction nozzle; 11. Negative pressure suction port; 12. Connection port; 13. Pressure plate; 14. Mounting sleeve; 15. Limiting ring; 16. Connecting ring; 301. Spring sleeve; 302. Spring push rod; 303. Mounting groove; 304. Connecting bracket; 305. Lifting shaft; 306. No. 1 slide groove; 307. Upper fixed plate; 308. Transmission rod; 309. Mounting rod; 310. Clamping plate; 311. Support rod; 312. Second slide groove; 313. Slide rod; 314. Lower fixed plate; 501. Drive plate; 502. Top rod; 503. Slide rail; 504. Rotating ring; 505. Gear; 506. Lead screw; 507. Threaded mating rod; 508. Gear ring; 509. Groove; 510. Connecting block; 511. Mounting sheet metal; 512. Sphere; 513. Ball seat; 514. Slider. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0033] The structure of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] like Figures 1 to 10 As shown, the negative pressure suction ring for myopia surgery with precisely adjustable adsorption force provided in this embodiment of the invention includes an upper ring shell 1, a clamping and fixing assembly 3, and a lifting and adjusting assembly 5. The clamping and fixing assembly 3 includes an upper fixing plate 307 and a lower fixing plate 314. The upper fixing plate 307 is disposed above the lower fixing plate 314. The upper fixing plate 307 and the lower fixing plate 314 are provided with a plurality of upper and lower fixed connections to the inner wall of the upper ring shell 1. A first sliding groove 306 is provided in the middle of the upper fixing plate 307. A lifting shaft 305 is installed in the first sliding groove 306. A connecting bracket 304 is rotatably installed in the middle of the lifting shaft 305. The lifting and adjusting assembly 5 includes a drive plate 501. One end of the drive plate 501 is rotatably installed on a slide rod 313. A groove 509 is provided on one side of the drive plate 501. A connecting block 510 is rotatably installed in the groove 509. One end of the connecting block 510 is fixedly connected to a mounting sheet metal 511. A top rod 502 is rotatably installed in the mounting sheet metal 511.

[0035] A sealing airbag 2 is fixedly connected to the upper edge of the upper ring housing 1. An airbag inlet 4 is provided on one side of the sealing airbag 2. A clamping and fixing assembly 3 is installed inside the upper ring housing 1. A lifting and adjusting assembly 5 is installed in conjunction with the clamping and fixing assembly 3. A lower ring housing 6 is installed on the lifting and adjusting assembly 5. Several evenly distributed mounting sleeves 14 are provided on the upper surface of the lower ring housing 6. A lifting ring 8 is fixedly connected to the lower end of the upper ring housing 1. The lifting ring 8 is installed inside the lower ring housing 6. A connecting port 12 is provided above the clamping and fixing assembly 3. A pressure plate 13 is fixedly connected to the outer surface of the connecting port 12. Several evenly distributed sealing protrusions 9 are fixedly connected to the outer surface of the lifting ring 8. A sealing mating block 7 is provided on the outer side of the sealing protrusions 9. The sealing mating block 7 is fixedly connected to the upper edge of the inner wall of the lower ring housing 6. A connecting ring 16 is fixedly connected to the lower surface of the lower ring housing 6. The inner wall of the connecting ring 16 is fixedly connected to... A limit ring 15 is connected to a suction nozzle 10 fixedly connected to the lower surface of a connecting ring 16. A negative pressure suction port 11 is provided on one side of the suction nozzle 10. The suction nozzle 10 is connected to the connecting port 12 through a clamping and fixing assembly 3. This allows the suction ring to be quickly installed on the femtosecond LASIK machine, which speeds up the surgical treatment and saves the workload of medical staff. Then, the suction port is connected to the negative pressure suction port 11, and the air outlet is connected to the air inlet 4 of the airbag. This allows the sealing airbag 2 to inflate and seal the suction ring and the connecting port 12. The negative pressure suction port 11 can create a negative pressure inside the suction ring, thereby suctioning the patient's eyeball and facilitating femtosecond LASIK surgery. When the clamping and fixing assembly 3 is activated, it can also activate the lifting and adjusting assembly 5. The lifting and adjusting assembly 5 can drive the lower ring shell 6 to move up and down along the lead screw 506, thereby achieving precise adjustment, increasing the applicability of the surgery, and improving the practicality of the suction ring.

[0036] A spring push rod 302 is provided at the other end of the connecting bracket 304. A mounting groove 303 is provided at the lower end of the spring push rod 302. A spring sleeve 301 is installed in the middle of the spring push rod 302. The spring sleeve 301 is located at the edge of the upper surface of the upper ring housing 1. The upper end of the spring push rod 302 cooperates with the pressure plate 13. Transmission rods 308 are rotatably mounted at both ends of the lifting shaft 305. Mounting rods 309 are rotatably mounted at the lower ends of the transmission rods 308 on both sides. Clamping plates 310 are fixedly connected to the lower ends of the mounting rods 309 on both sides. Support rods 311 are rotatably mounted on both sides of the lower end of the clamping plates 310. Lower fixing plates 314 are rotatably mounted at the lower ends of the support rods 311 on both sides. A mounting plate 314 is provided at the lower end of the support rods 311 on both sides. A second slide groove 312 is provided, and a slide rod 313 is installed in the second slide groove 312. The slide rod 313 is installed in the spring sleeve 301 via a spring push rod 302. When the negative pressure suction ring is put into the connection port 12, the spring push rod 302 contacts the pressure plate 13 and drives the spring push rod 302 to move downward along the spring sleeve 301. Through the connecting bracket 304, the lifting shaft 305 moves up and down in the first slide groove 306. The transmission rod 308 and the support rod 311 at both ends of the connecting bracket 304 are rotated and installed on the clamping plate 310, which can drive the clamping plate 310 to move inward, thereby clamping and fixing the connection port 12, and more quickly installing the negative pressure suction ring on the approximate surgical treatment machine.

[0037] The other end of the push rod 502 is fixedly connected to a ball 512, which is installed inside a ball seat 513. The ball seat 513 is fixedly connected to the upper surface of the slider 514, which is installed inside a rotating ring 504. The rotating ring 504 is installed inside a slide rail 503, which is fixedly connected to the middle of the inner wall of the upper ring housing 1. A gear ring 508 is fixedly connected to the outer surface of the rotating ring 504. Several evenly distributed gears 505 are connected to the outer side of the gear ring 508 through meshing. A lead screw 506 is fixedly connected to the lower surface of each gear 505. Each lead screw 506 is rotatably mounted on the upper ring housing 1 and extends to the bottom of the upper ring housing 1. The lower part of each lead screw 506 is open to... A threaded rod 507 is threadedly engaged and fixedly connected to the mounting sleeve 14. When the fixed plate 314 below the support rod 311 rotates, a drive plate 501 is installed on the slide rod 313 on the support rod 311. The drive plate 501 pushes the rotating ring 504 to rotate within the slide rail 503 via the push rod 502. Since the outer side of the rotating ring 504 is engaged with the gear 505 through the gear ring 508, it can drive the lead screw 506 to rotate. The lead screw 506 is threadedly engaged with the threaded rod 507, which can adjust the height between the upper ring housing 1 and the lower ring housing 6, thereby better achieving the function of fixing the eyeball.

[0038] refer to Figures 1 to 10 The method for using the negative pressure suction ring for myopia surgery, which allows for precise adjustment of suction force, includes the following steps:

[0039] S1. First, the suction ring is connected to the connection port 12 through the clamping and fixing component 3. The suction ring can be quickly installed on the femtosecond LASIK machine, which speeds up the surgical treatment efficiency and saves the workload of medical staff.

[0040] S2. Then connect the inhalation port to the negative pressure suction port 11, and then connect the outlet port to the air bag inlet 4. This can make the sealing air bag 2 inflate and seal the suction ring and the connection port 12. The negative pressure suction port 11 can create negative pressure inside the suction ring, thereby suctioning the patient's eyeball to facilitate femtosecond laser surgery.

[0041] S3. When the clamping and fixing component 3 is activated, the lifting and adjusting component 5 can be activated simultaneously. The lifting and adjusting component 5 can drive the lower ring housing 6 to move up and down along the lead screw 506, thereby achieving precise adjustment, increasing the applicability of the surgery, and improving the practicality of the suction ring.

[0042] Working principle of the invention:

[0043] In use, the suction ring is first connected to the connection port 12 via the clamping and fixing component 3, which allows for quick installation of the suction ring onto the femtosecond LASIK machine, accelerating surgical efficiency and saving the workload of medical staff. Then, the suction port is connected to the negative pressure suction port 11, and the air outlet is connected to the air inlet 4 of the airbag. This allows the sealing airbag 2 to inflate and seal the suction ring and connection port 12. The negative pressure suction port 11 creates negative pressure inside the suction ring, thereby suctioning the patient's eyeball and facilitating femtosecond LASIK surgery. When the clamping and fixing component 3 is activated, it also activates the lifting and adjusting component 5. The lifting and adjusting component 5 moves the lower ring housing 6 up and down along the lead screw 506, thereby achieving precise adjustment, increasing the applicability of the surgery, and improving the practicality of the suction ring.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can exercise their rights without departing from the scope of the present invention.

Claims

1. A negative pressure suction ring for myopia surgery with precisely adjustable suction force, comprising an upper ring shell (1), a clamping and fixing assembly (3), and a lifting and adjusting assembly (5), characterized in that: The clamping and fixing assembly (3) includes an upper fixing plate (307) and a lower fixing plate (314). The upper fixing plate (307) is located above the lower fixing plate (314). There are several upper fixing plates (307) and lower fixing plates (314), which are fixedly connected to the upper and lower sides of the inner wall of the upper ring shell (1). A first sliding groove (306) is provided in the middle of the upper fixing plate (307). A lifting shaft (305) is installed in the first sliding groove (306). A connecting bracket (304) is rotatably installed in the middle of the lifting shaft (305). The lifting adjustment assembly (5) includes a drive plate (501), one end of which is rotatably mounted on a slide rod (313). A groove (509) is provided on one side of the drive plate (501), and a connecting block (510) is rotatably mounted in the groove (509). One end of the connecting block (510) is fixedly connected to a mounting sheet metal (511), and a top rod (502) is rotatably mounted in the mounting sheet metal (511). The other end of the connecting bracket (304) is provided with a spring push rod (302), the lower end of the spring push rod (302) is provided with an installation groove (303), the middle part of the spring push rod (302) is provided with a spring sleeve (301), the spring sleeve (301) is provided at the edge of the upper surface of the upper ring shell (1), the upper end of the spring push rod (302) is matched with the pressure plate (13), and the two ends of the lifting shaft (305) are rotatably installed with transmission rods (308); The other end of the top rod (502) is fixedly connected to a ball (512), the ball (512) is installed in the ball seat (513), the ball seat (513) is fixedly connected to the upper surface of the slider (514), the slider (514) is installed in the rotating ring (504), the rotating ring (504) is installed in the slide rail (503), and the slide rail (503) is fixedly connected to the middle of the inner wall of the upper ring shell (1).

2. The negative pressure suction ring for myopia surgery with precisely adjustable adsorption force as described in claim 1, characterized in that: A sealing airbag (2) is fixedly connected to the upper edge of the upper ring shell (1). An airbag inlet (4) is provided on one side of the sealing airbag (2). A clamping and fixing assembly (3) is installed inside the upper ring shell (1). A lifting and adjusting assembly (5) is installed in cooperation with the clamping and fixing assembly (3). A lower ring shell (6) is installed in the lifting and adjusting assembly (5). Several evenly distributed mounting sleeves (14) are provided on the upper surface of the lower ring shell (6). A lifting ring (8) is fixedly connected to the lower end of the upper ring shell (1). The lifting ring (8) is installed inside the lower ring shell (6). A connection port (12) is provided above the clamping and fixing assembly (3). A pressure plate (13) is fixedly connected to the outer surface of the connection port (12).

3. The negative pressure suction ring for myopia surgery with precisely adjustable adsorption force as described in claim 2, characterized in that: The outer surface of the lifting ring (8) is fixedly connected with a number of evenly distributed sealing protrusions (9). A sealing mating block (7) is provided on the outer side of the sealing protrusions (9). The sealing mating block (7) is fixedly connected to the upper edge of the inner wall of the lower ring shell (6). A connecting ring (16) is fixedly connected to the lower surface of the lower ring shell (6). A limit ring (15) is fixedly connected to the inner wall of the connecting ring (16). A suction nozzle (10) is fixedly connected to the lower surface of the connecting ring (16). A negative pressure suction port (11) is provided on one side of the suction nozzle (10).

4. The negative pressure suction ring for myopia surgery with precisely adjustable adsorption force as described in claim 1, characterized in that: The lower ends of the transmission rods (308) on both sides are rotatably mounted with mounting rods (309), and the lower ends of the mounting rods (309) on both sides are fixedly connected with clamps (310). Support rods (311) are rotatably mounted on both sides of the lower ends of the clamps (310), and lower fixing plates (314) are rotatably mounted on the lower ends of the support rods (311) on both sides. The lower ends of the support rods (311) on both sides are provided with second slide grooves (312), and slide rods (313) are installed in the second slide grooves (312).

5. The negative pressure suction ring for myopia surgery with precisely adjustable adsorption force as described in claim 1, characterized in that: A gear ring (508) is fixedly connected to the outer surface of the rotating ring (504). A number of evenly distributed gears (505) are connected to the outer side of the gear ring (508) through tooth meshing. A lead screw (506) is fixedly connected to the lower surface of each gear (505). Each lead screw (506) is rotatably mounted on the upper ring housing (1) and extends to the lower part of the upper ring housing (1). A threaded mating rod (507) is connected to the lower part of each lead screw (506) through thread meshing. The threaded mating rod (507) is fixedly connected to the mounting sleeve (14).

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