Seedling pulling mechanism

Abstract

The invention discloses a seedling pulling mechanism which is characterized in that at least two seedling clamping rollers are fixedly mounted on a roller shaft, a left end pressure plate is fixedly mounted at the left end of the roller shaft, a right end pressure plate is fixedly mounted at the right end of the roller shaft, the seedling clamping rollers are located between the left end pressure plate and the right end pressure plate, and circular fixed seedling clamping plates are fixed on the outer circular surfaces of the seedling clamping rollers; a guide groove is formed in the seedling clamping roller; at least two seedling clamping push rods are installed in the seedling clamping roller, at least two reset springs and at least two movable seedling clamping plates are installed on the seedling clamping push rods, each movable seedling clamping plate is in sliding fit with the corresponding seedling clamping push rod, and the two ends of the reset spring at the left end abut against the position between the corresponding movable seedling clamping plate and the corresponding pressing disc at the left end respectively. The two ends of the middle end reset spring abut against the position between every two adjacent movable seedling clamping plates, and the movable seedling clamping plates are located in the guide grooves; a rolling ball retaining sleeve and a cylindrical cam are installed on the right side of the right-end pressing disc, the rolling ball retaining sleeve is fixedly connected with the right-end pressing disc, a rolling ball is installed in the rolling ball retaining sleeve, the rolling ball is of a spherical structure and abuts against the cam contour surface of the cylindrical cam, and the rolling ball retaining sleeve and the cylindrical cam can be matched in a relatively rotating mode; the right end of the seedling clamping push rod abuts against the rolling ball. The problems that abrasion of the cam contour surface of the cylindrical cam is aggravated and the seedling clamping push rod rotates are solved, the reliability and safety of equipment are improved, and the service life of the equipment is prolonged. And a modular structure is adopted, so that the manufacturing cost is reduced.

Description

Technical Field

[0001] The invention relates to the field of machinery, and in particular to a seedling pulling mechanism. Background Art

[0002] Prior art CN114568082A discloses a seedling throwing machine, the seedling pulling mechanism used in the seedling throwing machine includes a seedling pulling mechanism bracket, a cam plate, 16 seedling separation grid plates, and a roller; the cam plate and the seedling separation grid plates are fixed on the seedling pulling mechanism bracket, and the roller is rotatably mounted on the seedling pulling mechanism bracket. The seedling clamping assembly includes a slide bar, 5 clamping plate sliding sleeves, and 5 return springs. The clamping plate sliding sleeves are installed on the slide bar at intervals, and a roller is installed at the end of the slide bar, and the roller rests on the cam plate. The prior art has several technical defects: First, because the cam disk of the technology is a cylindrical cam, the cylindrical cam is a fixed part, and the roller can only rotate around its own axis. The axis of the roller intersects with the axis of the roller. When the roller drives the slide bar to rotate around the axis of the roller, the roller not only revolves around its own axis, but also revolves around the axis of the roller. There is not only rolling friction but also sliding friction between the matching surface of the roller and the cylindrical cam, which increases the wear of the matching surface of the roller and the cylindrical cam. In addition, the reaction force of the cylindrical cam on the slide bar will cause the slide bar to rotate. Second, the roller is an integral structure, which is difficult to process and assemble, and the cost is high. Summary of the invention

[0003] In view of this, the present invention proposes a seedling pulling mechanism, which solves the problems of aggravated wear of the cam profile surface of the cylindrical cam and self-rotation of the seedling clamping push rod, improves the reliability and safety of the equipment, and prolongs the service life of the equipment. The modular structure is adopted to reduce the manufacturing cost.

[0004] On the one hand, the present invention provides a seedling pulling mechanism, at least two seedling clamping rollers are fixedly installed on a roller shaft, a left-end pressure plate is fixedly installed on the left end of the roller shaft, and a right-end pressure plate is fixedly installed on the right end of the roller shaft, the seedling clamping roller is located between the left-end pressure plate and the right-end pressure plate, a circular fixed seedling clamping plate is fixed on the outer circumferential surface of the seedling clamping roller, and a guide groove is provided on the seedling clamping roller; at least two seedling clamping push rods are installed in the seedling clamping roller, and at least two return springs and at least two movable seedling clamping plates are installed on the seedling clamping push rods, and each movable seedling clamping plate is slidably matched with the seedling clamping push rod. The two ends of the left-end return spring respectively rest between the dynamic seedling clamping plate and the left-end pressure plate, and the two ends of the middle-end return spring respectively rest between the two adjacent dynamic seedling clamping plates, and the dynamic seedling clamping plate is located in the guide groove; a ball retaining sleeve and a cylindrical cam are installed on the right side of the right-end pressure plate, the ball retaining sleeve is fixedly connected to the right-end pressure plate, and a ball is installed in the ball retaining sleeve. The ball is a spherical structure, and the ball rests on the cam contour surface of the cylindrical cam. The ball retaining sleeve and the cylindrical cam can rotate relatively to each other, the left end of the seedling clamping push rod is connected to the left-end pressure plate, and the right end of the seedling clamping push rod rests on the ball.

[0005] In order to realize the process of slow loosening, long loosening, quick clamping and slow pulling of seedlings, in a further technical solution, the cylindrical cam includes a disc and a cylinder, the cylinder is fixed on the disc, and the cylinder and the disc are coaxial; the cam profile surface includes a first curved profile surface, a second curved profile surface, a first plane profile surface, and a second plane profile surface, the first curved profile surface, the second curved profile surface and the first plane profile surface are located on the end surface of the cylinder, and the second plane profile surface is located on the surface of the disc; the first curved profile surface is used to overcome the elastic force of the reset spring to push the clamping seedling push rod to move to the left to slowly loosen the seedlings; the first plane ... The first plane contour surface is used to keep the seedlings in a completely loosened state; the second curved contour surface is used to move the seedling clamping push rod to the right under the action of the elastic force of the reset spring to quickly clamp the seedlings; the second plane contour surface is used to keep the seedlings in a completely clamped state; the center angle R4 of the first plane contour surface is greater than the center angle R2 of the second plane contour surface, the center angle R3 of the first curved contour surface is more than twice the center angle R1 of the second curved contour surface, the center angle R2 of the second plane contour surface is greater than the center angle R3 of the first curved contour surface, and the cylinder height H1 is equal to the displacement stroke L1 of the dynamic seedling clamping plate.

[0006] In order to achieve the process of slow loosening, long loosening, quick clamping and slow pulling of seedlings, in a further technical scheme, the central angle R4 of the first plane contour surface is 150-170 degrees, the central angle R2 of the second plane contour surface is 90-100 degrees, the central angle R3 of the first curved contour surface is 20-30 degrees, and the central angle R1 of the second curved contour surface is 70-80 degrees; the sum of the central angle R4 of the first plane contour surface and the central angle R2 of the second plane contour surface and the central angle R3 of the first curved contour surface and the central angle R1 of the second curved contour surface is 360 degrees.

[0007] In order to reduce the cam profile of the cylindrical cam, avoid self-rotation of the rice-grassing push rod, improve the reliability and safety of the equipment, and extend the service life of the equipment, in a further technical scheme, the ball retaining sleeve includes an inner ring and an outer ring, an annular groove is formed between the inner ring and the outer ring, and the cylinder is inserted into the annular groove; a cylindrical hole is opened between the inner ring and the outer ring, and an oil nozzle hole is opened on the outer ring, the oil nozzle hole is communicated with the cylindrical hole, and a lubricating oil nozzle is installed on the oil nozzle hole; the ball is located in the cylindrical hole, and the right end of the rice-grassing push rod is inserted into the cylindrical hole; the roller shaft and the inner ring are fixedly connected by a locating pin.

[0008] In order to improve the efficiency of clamping the seedlings, in a further technical solution, the seedling clamping push rods include three, and the three seedling clamping push rods are evenly arranged; three cylindrical holes are opened between the inner ring and the outer ring, and three oil nozzle holes are opened on the outer ring, and the three oil nozzle holes are respectively communicated with the three cylindrical holes.

[0009] In order to improve the sealing performance, in a further technical solution, a sealing ring is installed at the right end of the rice seedling clamping push rod, the right end of the rice seedling clamping push rod is inserted into the inner ring of the sealing ring, the outer ring of the sealing ring is inserted into the right end pressure plate, and the end face of the sealing ring cooperates with the end face of the ball retaining sleeve to form a plane seal.

[0010] In order to realize the relative rotation between the roller shaft and the cylindrical cam, in a further technical solution, a bearing seat is installed at the right end of the roller shaft, and the cylindrical cam is connected to the bearing seat.

[0011] In order to improve the efficiency of clamping the seedlings, in a further technical solution, the seedling clamping rollers include 21, three fixing rods are fixed inside the 21 seedling clamping rollers, and the two ends of the three fixing rods are respectively connected and fixed to the left end pressure plate and the right end pressure plate to connect and fix the 21 seedling clamping rollers.

[0012] In order to improve the efficiency of seedling clamping, in a further technical solution, 7 return springs and 7 movable seedling clamping plates are installed on the seedling clamping push rod.

[0013] Compared with the prior art, the seedling pulling mechanism of the present invention has the following beneficial effects: The present invention adopts a plurality of seedling clamping rollers to assemble each other, and the corresponding number of seedling clamping rollers is assembled according to actual needs. Each seedling clamping roller has the same structure, so that modular production is realized, and production cost and maintenance cost are reduced.

[0014] In the present invention, a ball is installed in a ball retaining sleeve, the ball is a spherical structure, and the ball abuts against the cam profile surface of the cylindrical cam. The ball can rotate 360 ​​degrees, and there is only rolling friction between the ball and the cam profile surface of the cylindrical cam, and there is no sliding friction, which reduces the wear of the cam profile surface of the cylindrical cam, avoids the self-rotation of the rice seedling clamping push rod, improves the reliability and safety of the equipment, and prolongs the service life of the equipment.

[0015] The first curved contour surface of the present invention is used to overcome the elastic force of the return spring to push the seedling clamping push rod to move to the left side, and slowly loosen the seedlings; the first plane contour surface is used to keep the seedlings in a completely loosened state; the second curved contour surface is used to move the seedling clamping push rod to the right side under the action of the elastic force of the return spring, and quickly clamp the seedlings; the second plane contour surface is used to keep the seedlings in a completely clamped state, realizing the process of slow loosening, long loosening, quick clamping, and slow seedling pulling, ensuring that the seedling pulling process is accurate and reliable, quick to take and slow to release, and no damage to the seedlings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings: Figure 1 A three-dimensional diagram of a seedling pulling mechanism of the present invention; Figure 2 for Figure 1 The main view; Figure 3 for Figure 2 A-A sectional view; Figure 4 for Figure 2Left view of Figure 5 for Figure 1 Schematic diagram of cylindrical cam; Figure 6 for Figure 5 Top view; Figure 7 for Figure 5 Main view; Figure 8 for Figure 1 Schematic diagram of a ball retaining sleeve; Fig. 9 for Figure 8 A top view of Fig.10 for Fig. 9 B-B section view. DETAILED DESCRIPTION

[0017] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0018] like Figure 1 and Figure 2 and Figure 3 and Figure 4 As shown, the present invention preferably adopts a seedling pulling mechanism, 21 seedling clamping rollers 6 are fixedly installed on the roller shaft 1, a left end pressure plate 7 is fixedly installed on the left end of the roller shaft 1, and a right end pressure plate 11 is fixedly installed on the right end of the roller shaft 1, the 21 seedling clamping rollers 6 are located between the left end pressure plate 7 and the right end pressure plate 11, a circular fixed seedling clamping plate 61 is fixed on the outer circumferential surface of the seedling clamping roller 6, and a guide groove 60 is provided on the seedling clamping roller 6; three fixing rods 9 are fixed in the 21 seedling clamping rollers 6, and the two ends of the three fixing rods 9 are respectively connected and fixed to the left end pressure plate 7 and the right end pressure plate 11, so as to connect and fix the 21 seedling clamping rollers 6. The 21 seedling clamping rollers 6 can pull 21 seedlings by rotating one circle. The present invention adopts a plurality of seedling clamping rollers 6 to be assembled with each other, and the corresponding number of seedling clamping rollers 6 is assembled according to actual needs. Each seedling clamping roller 6 has the same structure, and the modular production is realized, which reduces the production cost and maintenance cost.

[0019] Three seedling clamping push rods 8 are installed in the seedling clamping roller 6. The three seedling clamping push rods 8 are evenly arranged and the interval angle of the three seedling clamping push rods 8 is 120 degrees. Seven return springs 80 and seven movable seedling clamping plates 81 are installed on the seedling clamping push rods 8. Each movable seedling clamping plate 81 is slidably matched with the seedling clamping push rods 8. The two ends of the left end return spring 80 are respectively against the movable seedling clamping plate 81 and the left end pressure plate 7. The two ends of the middle end return spring 80 are respectively against the adjacent two movable seedling clamping plates 81. The movable seedling clamping plate 81 is located in the guide groove 60. Rotating 120 degrees can pull out 7 seedlings, and rotating 360 degrees can pull out 21 seedlings.

[0020] like Figure 3 As shown, a ball retaining sleeve 4 and a cylindrical cam 3 are installed on the right side of the right end pressure plate 11, the ball retaining sleeve 4 is fixedly connected to the right end pressure plate 11, a ball 10 is installed in the ball retaining sleeve 4, the ball 10 is a spherical structure, the ball 10 abuts against the cam profile surface of the cylindrical cam 3, the ball retaining sleeve 4 and the cylindrical cam 3 can rotate relatively, the left end of the vine clamping push rod 8 is connected to the left end pressure plate 7, and the right end of the vine clamping push rod 8 abuts against the ball 10. The ball 10 can rotate 360 ​​degrees, and there is only rolling friction between the ball 10 and the cam profile surface of the cylindrical cam 3, and there is no sliding friction, which reduces the wear of the cam profile surface of the cylindrical cam 3, avoids the self-rotation of the vine clamping push rod, improves the reliability and safety of the equipment, and extends the service life of the equipment. A sealing ring 13 is installed at the right end of the rice-clamping push rod 8, the right end of the rice-clamping push rod 8 is inserted into the inner ring of the sealing ring 13, the outer ring of the sealing ring 13 is inserted into the right end pressure plate 11, and the end face of the sealing ring 13 cooperates with the end face of the ball retaining sleeve 4 to form a plane seal. A bearing seat 2 is installed at the right end of the roller shaft 1, and a cylindrical cam 3 is connected to the bearing seat 2.

[0021] like Figure 5 and Figure 6 and Figure 7As shown, the cylindrical cam 3 includes a disc 31 and a cylinder 30, the cylinder 30 is fixed on the disc 31, and the cylinder 30 is coaxial with the disc 31; the cam profile surface includes a first curved profile surface 300, a second curved profile surface 302, a first plane profile surface 301, and a second plane profile surface, the first curved profile surface 300, the second curved profile surface 302 and the first plane profile surface 301 are located on the end surface of the cylinder 30, and the second plane profile surface is located on the surface of the disc 31; the first curved profile surface 300 is used to overcome the elastic force of the reset spring 80 to push the clamping seedling push rod 8 to move to the left side, and slowly release the seedlings; the first plane profile surface 301 01 is used to keep the seedlings in a completely loosened state; the second curved contour surface 302 is used to move the seedling clamping push rod 8 to the right under the elastic force of the reset spring 80 to quickly clamp the seedlings; the second plane contour surface is used to keep the seedlings in a completely clamped state; the center angle R4 of the first plane contour surface 301 is greater than the center angle R2 of the second plane contour surface, the center angle R3 of the first curved contour surface 300 is more than twice the center angle R1 of the second curved contour surface 302, the center angle R2 of the second plane contour surface is greater than the center angle R3 of the first curved contour surface 300, and the height H1 of the cylinder 30 is equal to the displacement stroke L1 of the dynamic seedling clamping plate 81. The center angle R4 of the first plane contour surface 301 is 160 degrees, the center angle R2 of the second plane contour surface is 95 degrees, the center angle R3 of the first curved contour surface 300 is 25 degrees, and the center angle R1 of the second curved contour surface 302 is 80 degrees; the sum of the center angle R4 of the first plane contour surface 301, the center angle R2 of the second plane contour surface, the center angle R3 of the first curved contour surface 300, and the center angle R1 of the second curved contour surface 302 is 360 degrees. The process of slow loosening, long loosening, fast clamping, and slow pulling of seedlings is realized, ensuring that the pulling process is accurate and reliable, fast picking and slow release, and no damage to the seedlings.

[0022] like Figure 8 and Fig. 9 and Fig.10 As shown, the ball retaining sleeve 4 includes an inner ring 44 and an outer ring 43, an annular groove 40 is formed between the inner ring 44 and the outer ring 43, and the cylinder 30 is inserted into the annular groove 40; three cylindrical holes 41 are opened between the inner ring 44 and the outer ring 43, and three oil nozzle holes 42 are opened on the outer ring 43, the oil nozzle holes 42 are communicated with the cylindrical holes 41, and three lubricating oil nozzles 5 are installed on the three oil nozzle holes 42. Lubricating oil is injected into the cylindrical hole 41 through the three lubricating oil nozzles 5. The ball 10 is located in the cylindrical hole 41, and the right ends of the three vine clamping push rods 8 are inserted into the three cylindrical holes 41; the roller shaft 1 is fixedly connected to the inner ring 44 by the positioning pin 12. The self-rotation of the vine clamping push rod is avoided, the reliability and safety of the equipment are improved, and the service life of the equipment is extended.

[0023] The present invention preferably adopts a seedling pulling mechanism whose working process is as follows: the roller shaft 1 drives 21 seedling clamping rollers 6, the seedling clamping push rod 8 and the ball retaining sleeve 4 to rotate, the cylindrical cam 3 is fixed, and the ball 10 rolls on the cam contour surface. The ball 10 has rolling friction relative to the right end of the seedling clamping push rod 8, and the ball 10 has rolling friction relative to the cam contour surface. There is no sliding friction, which reduces the wear of the cam contour surface of the cylindrical cam 3, avoids the self-rotation of the seedling clamping push rod, improves the reliability and safety of the equipment, and extends the service life of the equipment. The first curved contour surface 300 overcomes the elastic force of the return spring 80 to push the rolling ball 10 and the seedling clamping push rod 8 to move to the left, the dynamic seedling clamping plate 81 moves to the left, the gap between the dynamic seedling clamping plate 81 and the fixed seedling clamping plate 61 increases, the seedlings are slowly released, and a slow loosening process is achieved; then, the rolling ball 10 is located on the first plane contour surface 301, and the seedlings remain in a completely loosened state, achieving a long-term loosened state; then, the rolling ball 10 is located on the second curved contour surface 302, and the seedling clamping push rod 8 moves to the right under the elastic force of the return spring 80, the gap between the dynamic seedling clamping plate 81 and the fixed seedling clamping plate 61 decreases, and the seedlings are quickly clamped to achieve a quick clamping process; finally, the roller shaft 1 continues to rotate, the rolling ball 10 is located on the second plane contour surface, the seedlings remain in a completely clamped state, and the seedlings are slowly pulled out, ensuring that the seedling pulling process is accurate and reliable, quick to take and slow to release, and no damage to the seedlings.

[0024] The above-mentioned technologies are common knowledge to those skilled in the art. The above-mentioned are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A seedling pulling mechanism, characterized in that: At least two seedling clamping rollers (6) are fixedly mounted on the roller shaft (1); a left end pressure plate (7) is fixedly mounted on the left end of the roller shaft (1); a right end pressure plate (11) is fixedly mounted on the right end of the roller shaft (1); the seedling clamping roller (6) is located between the left end pressure plate (7) and the right end pressure plate (11); a circular fixed seedling clamping plate (61) is fixed on the outer circumferential surface of the seedling clamping roller (6); and a guide groove (60) is provided on the seedling clamping roller (6); at least two seedling clamping push rods (8) are mounted inside the seedling clamping roller (6); at least two return springs (80) and at least two movable seedling clamping plates (81) are mounted on the seedling clamping push rod (8); each movable seedling clamping plate (81) is slidably matched with the seedling clamping push rod (8); two ends of the left end return spring (80) are respectively abutted against the seedling clamping plate (81); Between the movable seedling clamping plate (81) and the left end pressure plate (7), the two ends of the middle end return spring (80) respectively abut between two adjacent movable seedling clamping plates (81), and the movable seedling clamping plate (81) is located in the guide groove (60); a ball retaining sleeve (4) and a cylindrical cam (3) are installed on the right side of the right end pressure plate (11); the ball retaining sleeve (4) is fixedly connected to the right end pressure plate (11); a ball (10) is installed in the ball retaining sleeve (4); the ball (10) is a spherical structure; the ball (10) abuts against the cam profile surface of the cylindrical cam (3); the ball retaining sleeve (4) and the cylindrical cam (3) can rotate relative to each other; the left end of the seedling clamping push rod (8) is connected to the left end pressure plate (7), and the right end of the seedling clamping push rod (8) abuts against the ball (10).

2. The seedling pulling mechanism according to claim 1, characterized in that: The cylindrical cam (3) comprises a disc (31) and a cylinder (30), the cylinder (30) being fixed on the disc (31), and the cylinder (30) and the disc (31) being coaxial; the cam profile surface comprises a first curved profile surface (300), a second curved profile surface (302), a first plane profile surface (301), and a second plane profile surface; the first curved profile surface (300), the second curved profile surface (302), and the first plane profile surface (301) are located on the end surface of the cylinder (30), and the second plane profile surface is located on the surface of the disc (31); the first curved profile surface (300) is used to overcome the elastic force of the return spring (80) to push the seedling clamping push rod (8) to move to the left side, thereby slowly releasing the seedlings; The planar contour surface (301) is used to keep the seedlings in a completely loosened state; the second curved contour surface (302) is used to move the seedling clamping push rod (8) to the right under the elastic force of the return spring (80) to quickly clamp the seedlings; the second planar contour surface is used to keep the seedlings in a completely clamped state; the center angle R4 of the first planar contour surface (301) is greater than the center angle R2 of the second planar contour surface, the center angle R3 of the first curved contour surface (300) is greater than twice the center angle R1 of the second curved contour surface (302), the center angle R2 of the second planar contour surface is greater than the center angle R3 of the first curved contour surface (300), and the height H1 of the cylinder (30) is equal to the displacement stroke L1 of the movable seedling clamping plate (81).

3. The seedling pulling mechanism according to claim 2, characterized in that: The center angle R4 of the first planar contour surface (301) is 150-170 degrees, the center angle R2 of the second planar contour surface is 90-100 degrees, the center angle R3 of the first curved contour surface (300) is 20-30 degrees, and the center angle R1 of the second curved contour surface (302) is 70-80 degrees; the sum of the center angle R4 of the first planar contour surface (301) and the center angle R2 of the second planar contour surface, the center angle R3 of the first curved contour surface (300) and the center angle R1 of the second curved contour surface (302) is 360 degrees.

4. The seedling pulling mechanism according to claim 2, characterized in that: The ball retaining sleeve (4) comprises an inner ring (44) and an outer ring (43); an annular groove (40) is formed between the inner ring (44) and the outer ring (43); a cylinder (30) is inserted into the annular groove (40); a cylindrical hole (41) is formed between the inner ring (44) and the outer ring (43); an oil nozzle hole (42) is formed on the outer ring (43); the oil nozzle hole (42) is communicated with the cylindrical hole (41); a lubricating oil nozzle (5) is installed on the oil nozzle hole (42); the ball (10) is located in the cylindrical hole (41); the right end of the rice seedling clamping push rod (8) is inserted into the cylindrical hole (41); the roller shaft (1) is fixedly connected to the inner ring (44) by a positioning pin (12).

5. The seedling pulling mechanism according to claim 4, characterized in that: The seedling clamping push rods (8) include three, and the three seedling clamping push rods (8) are evenly arranged; three cylindrical holes (41) are provided between the inner ring (44) and the outer ring (43); three oil nozzle holes (42) are provided on the outer ring (43); and the three oil nozzle holes (42) are respectively communicated with the three cylindrical holes (41).

6. The seedling pulling mechanism according to claim 5, characterized in that: A sealing ring (13) is installed at the right end of the rice seedling clamping push rod (8), the right end of the rice seedling clamping push rod (8) is inserted into the inner ring of the sealing ring (13), the outer ring of the sealing ring (13) is inserted into the right end pressure plate (11), and the end surface of the sealing ring (13) cooperates with the end surface of the ball retaining sleeve (4) to form a plane seal.

7. The seedling pulling mechanism according to claim 6, characterized in that: A bearing seat (2) is installed at the right end of the roller shaft (1), and a cylindrical cam (3) is connected to the bearing seat (2).

8. The seedling pulling mechanism according to claim 1, characterized in that: The 21 seedling clamping rollers (6) are provided, and three fixing rods (9) are fixed inside the 21 seedling clamping rollers (6). The two ends of the three fixing rods (9) are respectively connected and fixed to a left end pressure plate (7) and a right end pressure plate (11), thereby connecting and fixing the 21 seedling clamping rollers (6).

9. The seedling pulling mechanism according to claim 1, characterized in that: Seven return springs (80) and seven movable seedling clamping plates (81) are installed on the seedling clamping push rod (8).

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