CN117869414A - A piston device - Google Patents

Abstract

The present invention discloses a piston device, belonging to the field of pistons, including a piston cylinder, the inner top of the piston cylinder is slidably connected with an upper piston rod, and the top of the piston cylinder is provided with a sealing mechanism; the sealing mechanism includes a fixing part fixed to the inner wall of the top of the piston cylinder, and a sealing part is fixed inside the fixing part; the fixing part fixes the sealing part to the inside of the piston cylinder, so that the upper piston rod can move back and forth inside the piston cylinder. The contact area between the protective tube and the X-shaped sealing ring is small, which reduces friction, and PTFE is a material with the smallest known friction coefficient, which further reduces friction, so the contact pressure between the X-shaped sealing ring and the protective tube does not need to be too large, and at the same time, the effect of the working fluid pressure in the piston further reduces the contact pressure. Under low pressure, the PTFE material is wear-resistant and has a long service life, and the elastic force of the surrounding rubber has a self-repairing effect on wear, reducing the wear on the X-shaped sealing ring.

Description

A piston device

Technical Field

The present invention relates to the field of pistons, and more particularly to a piston device.

Background technique

The piston rod is a connecting component that supports the piston to do work. It is mostly used in oil cylinders and cylinder motion actuators. It is a moving component that moves frequently and has high technical requirements. Take the hydraulic cylinder as an example. It consists of: cylinder barrel, piston rod, piston, and end cover. The quality of its processing directly affects the life and reliability of the entire product.

A Chinese patent with authorization announcement number CN114151406A discloses a piston device that can reduce the reverse impact energy between the balancing mechanism and the transmission mechanism as a whole and the driving mechanism, and on the other hand, can also reduce the reverse impact energy transmitted from the outside; thereby, the impact of the reverse impact force on the piston device can be reduced, effectively reducing the mechanical damage of the piston device.

Although the above patent solves the problem that when the piston device moves, the processing object suddenly breaks, causing a huge reverse impact force on the piston device, resulting in damage to the shaft, bearings and other parts of the piston device, but the reciprocating piston device generally relies on the friction between the piston seal and the piston cylinder wall, and the friction between the piston rod and the piston end cover shaft hole seal to achieve sealing and positioning. The friction damage of the seal leads to output power loss; and the seal is always in a state of motion, resulting in constant wear and tear of the seal, which needs to be replaced frequently. However, when replacing the seal, the piston body needs to be disassembled, which increases the maintenance time and makes replacing the seal more cumbersome.

Summary of the invention

In view of the problems existing in the prior art, the purpose of the present invention is to provide a piston device, which reduces friction by reducing the contact area between the protective tube and the X-type sealing ring, and PTFE is the material with the smallest known friction coefficient, which further reduces friction. Therefore, the contact pressure between the X-type sealing ring and the protective tube does not need to be too large. At the same time, the contact pressure is further reduced by the effect of the working fluid pressure in the piston. Under low pressure, the PTFE material is wear-resistant and has a long service life. The elastic force of the surrounding rubber has a self-repairing effect on wear, thereby reducing the wear on the X-type sealing ring.

To solve the above problems, the present invention adopts the following technical solutions.

A piston device comprises a piston cylinder, an upper piston rod is slidably connected to the inner top of the piston cylinder, and a sealing mechanism is arranged on the top of the piston cylinder;

The sealing mechanism comprises a fixing member fixed to the inner wall of the top of the piston cylinder, and a sealing member is fixed inside the fixing member;

A fixing member, wherein the fixing member fixes the sealing member inside the piston cylinder so that the upper piston rod can reciprocate inside the piston cylinder;

The fixing member comprises a piston gland fixedly connected to the top of the piston cylinder by threads, and a sealing support is placed on the inner upper end of the piston cylinder;

A sealing member is pressed against the upper piston rod to increase the sealing performance between the upper piston rod and the piston cylinder.

The sealing component includes: a protective tube is sleeved on the outer surface of the upper piston rod, a lower conical pressure ring is arranged on the top of the sealing support, an elastomer is placed on the outer surface of the lower conical pressure ring, an X-shaped sealing ring is arranged between the elastomer and the lower conical pressure ring, an upper conical pressure ring is placed on the inner surface of the upper half of the X-shaped sealing ring, the upper conical pressure ring and the lower conical pressure ring are not in contact with the protective tube, and the inner surface protrusion of the X-shaped sealing ring is in contact with the protective tube.

Furthermore, a water outlet pagoda head is fixedly connected to the left side of the piston cylinder, a water outlet of the water outlet pagoda head is fixedly connected to a flexible watering pipe, and a water outlet of the flexible watering pipe is fixedly connected to a rigid watering pipe.

Furthermore, a guide sleeve is fixedly connected to the top outer surface of the upper piston rod, a linear bearing is fixedly connected to the bottom of the guide sleeve, the center lines of the linear bearing, the upper piston rod and the piston cylinder coincide, and the X-shaped sealing ring and the protective tube are both made of PTFE.

Furthermore, the bottom of the piston cylinder is connected to a soil temperature regulating member via a thread, the inner top of the soil temperature regulating member is fixedly connected to a lower piston, a first O-shaped support is movably connected between the top of the lower piston and the piston cylinder, a second O-shaped support is movably connected below the first O-shaped support, a first O-ring is movably connected between the first O-shaped support and the second O-shaped support, the bottom of the soil temperature regulating member is movably connected to a water inlet pagoda head rotating cylinder via a thread, the bottom of the water inlet pagoda head rotating cylinder is movably connected to a water inlet pagoda head, the inner bottom of the water inlet pagoda head rotating cylinder is movably connected to a fourth O-shaped support, the upper part of the fourth O-shaped support is movably connected to a third O-shaped support, and a second O-ring is movably connected between the third O-shaped support and the fourth O-shaped support.

Furthermore, a sleeve is rotatably connected to the top outer surface of the piston cylinder, a plurality of extrusion rods are extended from the inner wall of the sleeve, and second movable grooves are provided inside the piston cylinder at positions corresponding to the plurality of extrusion rods.

Furthermore, extrusion grooves are provided inside the elastic body corresponding to the movement tracks of the multiple extrusion rods, and the shapes of the multiple extrusion grooves are all crescent-shaped, and the side of the extrusion rod close to the elastic body points to the inner protruding position of the elastic body.

Furthermore, the plurality of piston cylinders extend toward the position of the sleeve to form a second extension block, the interior of the sleeve is provided with a third movable groove for accommodating the movement of the plurality of second extension blocks, and the interior of the plurality of third movable grooves is provided with a second spring welded to the second extension block.

Furthermore, an extension rod is slidably connected to the inner top end of the sleeve, and multiple extension rods are extended from one side away from the X-shaped sealing ring to form a first extension block. First movable grooves are opened inside the sleeve at positions corresponding to the multiple first extension blocks, and multiple first extension blocks are slidably connected to the inside of the first movable grooves.

Furthermore, a first spring is welded to the bottom of each of the plurality of extending rods, and the plurality of first springs are in a naturally extended state when the extending rods do not move downward.

Furthermore, the outer surface of the piston gland extends to form an outer cylinder, which is located directly above the extension rod. A sealing gasket is fixedly connected between the piston gland and the outer cylinder, and a plurality of circular holes in a circular array with an angle of five degrees are provided at the inner bottom of the outer cylinder corresponding to the position of the extension rod.

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

1. This solution reduces friction by reducing the contact area between the protective tube and the X-type sealing ring. PTFE is a material with the smallest known friction coefficient, which further reduces friction. Therefore, the contact pressure between the X-type sealing ring and the protective tube does not need to be too large. At the same time, the effect of the working fluid pressure in the piston further reduces the contact pressure. Under low pressure, the PTFE material is wear-resistant and has a long service life. The elastic force of the surrounding rubber has a self-repairing effect on wear, thereby reducing the wear on the X-type sealing ring.

2. This solution squeezes the X-shaped sealing ring through the elastic body. As the wear degree of the X-shaped sealing ring increases, the squeezing of the X-shaped sealing ring by the elastic body is gradually increased, so that the X-shaped sealing ring is always kept in contact with the protective tube, so that the X-shaped sealing ring can be used for a longer time, and the X-shaped sealing ring does not need to be replaced when it encounters some wear. The extrusion rod moves to gradually squeeze the extrusion groove, so that the raised position of the X-shaped sealing ring is always in contact with the protective tube.

3. In this solution, while the sleeve rotates, the second extension block rotates relatively inside the third movable groove, so that the second extension block squeezes the second spring, making the sleeve rotate more smoothly. Under the action of the second spring, the sleeve can return to the original position with the squeezing rod, so that the squeezing rod can be reused.

4. This solution moves the extension rod so that the extension rod moves downward with the first extension block, which facilitates the movement of the first extension block inside the first movable groove. The first movable groove restricts the movement of the extension rod by restricting the first extension block, making the fixation of the sleeve and the piston cover more stable.

5. This solution limits the movement of the piston gland after the extending rod is inserted into the round hole, so that the piston gland will not come off when the device vibrates. The sleeve always squeezes the outer cylinder counterclockwise through the extending rod, and the piston gland rotates counterclockwise to strengthen the fixation between the piston cylinder, thereby preventing the piston gland from coming off when the device vibrates. The sealing gasket further strengthens the seal between the piston gland and the piston cylinder to prevent the liquid inside the piston cylinder from flowing out when the sleeve is rotated to adjust the contact degree between the X-shaped sealing ring and the protective tube.

6. This solution makes the center lines of the linear bearing, upper piston rod and piston cylinder coincide with each other, so that when the linear bearing moves the upper piston rod, the upper piston rod is centered in the reciprocating motion. The improvement in processing accuracy can eliminate the sealing ring on the piston in general applications, reducing friction power loss and sealing ring failure loss.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of a piston device of the present invention;

FIG2 is a cross-sectional view of a piston of the present invention;

FIG3 is an exploded view of the piston of the present invention;

FIG4 is a diagram showing a use scenario of the piston of the present invention;

FIG5 is an enlarged view of part A of FIG2 ;

FIG6 is a partial cross-sectional view of the piston of the present invention;

Fig. 7 is a half-section view of the sleeve of the present invention;

FIG. 8 is a schematic structural diagram of the piston gland of the present invention.

Description of the numbers in the figure:

1. Upper piston rod; 2. Second extension block; 3. Second moving groove; 4. Extrusion groove; 5. Third moving groove; 6. Sealing pad; 7. Sealing mechanism; 71. Sealing element; 711. Protective tube; 712. Lower conical pressing ring; 713. Elastomer; 714. X-shaped sealing ring; 715. Upper conical pressing ring; 72. Fixing element; 721. Piston gland; 722. Sealing support; 8. Piston cylinder; 9. First O-shaped support; 10. First O-shaped ring; 11. Second O-shaped support; 12. Lower piston; 13. Soil temperature regulating part; 14. Water inlet pagoda head rotating cylinder; 15. Third O-shaped support; 16. Second O-shaped ring; 17. Fourth O-shaped support; 18. Water inlet pagoda head; 19. Water outlet pagoda head; 20. Flexible watering pipe; 21. Rigid watering pipe; 22. Linear bearing; 23. Guide sleeve; 24. Sleeve; 25. Extrusion rod; 26. Extension rod; 27. First extension block; 28. First moving groove; 29. First spring; 30. Outer cylinder; 31. Round hole; 32. Second spring.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative work are within the scope of protection of the present invention.

Embodiment 1:

Please refer to Figures 1 to 6, a piston device includes a piston cylinder 8, the top of the piston cylinder 8 is slidably connected to the upper piston rod 1, and the top of the piston cylinder 8 is provided with a sealing mechanism 7; the sealing mechanism 7 includes a fixing member 72 fixed to the inner wall of the top of the piston cylinder 8, and a sealing member 71 is fixed inside the fixing member 72; the fixing member 72 fixes the sealing member 71 inside the piston cylinder 8, so that the upper piston rod 1 can reciprocate inside the piston cylinder 8; the fixing member 72 includes a piston gland 7 fixedly connected to the top of the piston cylinder 8 by a thread 21, a sealing support 722 is placed at the upper end of the piston cylinder 8; a sealing member 71, the sealing member 71 squeezes the upper piston rod 1 to increase the sealing between the upper piston rod 1 and the piston cylinder 8, the sealing member 71 includes: a protective tube 711 is sleeved on the outer surface of the upper piston rod 1, a lower conical pressing ring 712 is arranged on the top of the sealing support 722, an elastic body 713 is placed on the outer surface of the lower conical pressing ring 712, an X-shaped sealing ring 714 is arranged between the elastic body 713 and the lower conical pressing ring 712, the X-shaped sealing ring 71 An upper conical pressing ring 715 is placed on the inner surface of the upper half of 4, and the upper conical pressing ring 715 and the lower conical pressing ring 712 are not in contact with the protection tube 711. The inner surface protrusion of the X-shaped sealing ring 714 fits the protection tube 711. The bottom of the piston cylinder 8 is connected to the soil temperature regulating member 13 through a thread, and the inner top of the soil temperature regulating member 13 is fixedly connected to the lower piston 12. The top of the lower piston 12 is movably connected to the piston cylinder 8 with a first O-shaped support 9, and the lower part of the first O-shaped support 9 is movably connected to the second O-shaped support 11. A first O-ring 10 is movably connected between the first O-shaped support 9 and the second O-shaped support 11, the bottom of the soil temperature regulating member 13 is movably connected to a water inlet pagoda head rotating cylinder 14 through a thread, the bottom of the water inlet pagoda head rotating cylinder 14 is movably connected to a water inlet pagoda head 18, the inner bottom of the water inlet pagoda head rotating cylinder 14 is movably connected to a fourth O-shaped support 17, the upper part of the fourth O-shaped support 17 is movably connected to a third O-shaped support 15, and a second O-ring 16 is movably connected between the third O-shaped support 15 and the fourth O-shaped support 17.

First, the protective tube 711 is put on the surface of the upper piston rod 1. Since the protective tube 711 is a material that is easily deformed by heat, the protective tube 711 is heated so that the protective tube 711 can be firmly put on the surface of the upper piston rod 1 after cooling. The upper piston rod 1 is inserted into the interior of the piston cylinder 8, and then the sealing support 722 is placed in the interior of the piston cylinder 8. Then, the lower conical pressing ring 712 is placed on the surface of the sealing support 722, and then the X-shaped sealing ring 714 is placed on the surface of the sealing support 722. Then, between the X-shaped sealing ring 714 and the protective tube 711, The upper conical pressing ring 715 is filled with the elastomer 713 from the gap between the X-shaped sealing ring 714 and the piston cylinder 8, and the piston gland 721 is rotated and fixed on the top of the piston cylinder 8, and then the lower piston 12 is fixed by threads at the bottom of the piston cylinder 8. The first O-shaped support 9, the first O-shaped ring 10 and the second O-shaped support 11 are placed between the piston cylinder 8 and the lower piston 12 in sequence, and the water inlet pagoda head rotating cylinder 14 is fixed by threads at the bottom of the soil temperature regulating member 13, and the third O-shaped support 15, the second O-ring 16 and the fourth O-shaped support 17 are used to fix the water inlet The pagoda head 18 pumps water into the piston cylinder 8 through the water inlet pagoda head 18, and the inner cavity of the piston cylinder 8 is pressurized by the movement of the upper piston rod 1 again, so that the water reaches the inside of the flexible watering pipe 20 after passing through the water outlet pagoda head 19, and then reaches the rigid watering pipe 21 again, and the rigid watering pipe 21 is used to replenish water to the plants. When the upper piston rod 1 moves, the contact area between the protection tube 711 and the X-shaped sealing ring 714 is small, which reduces friction, and PTFE is a material with the smallest known friction coefficient, which reduces friction again, so the contact pressure between the X-shaped sealing ring 714 and the protection tube 711 is not The contact pressure is further reduced due to the working fluid pressure in the piston. Under low pressure, the PTFE material is wear-resistant and has a long service life. The elastic force of the surrounding rubber has a self-repairing effect on wear, thereby reducing the wear on the X-shaped sealing ring 714 and avoiding the need to replace the X-shaped sealing ring 714 after wear. There is no need for a rubber O-ring coated with PTFE. The coated O-ring is made by inserting PTFE into a rubber ring and then welding the joint. This is likely to cause leakage points and early failure risks at the joint. At the same time, the existing coating process cannot produce a smaller coated O-ring.

As shown in FIG. 4 , a guide sleeve 23 is fixedly connected to the top outer surface of the upper piston rod 1 , a linear bearing 22 is fixedly connected below the guide sleeve 23 , and the center lines of the linear bearing 22 , the upper piston rod 1 and the piston cylinder 8 coincide.

By aligning the center lines of the linear bearing 22, the upper piston rod 1 and the piston cylinder 8, when the linear bearing 22 moves the upper piston rod 1, the upper piston rod 1 is centered in the reciprocating motion. The improvement in processing accuracy allows the piston upper sealing ring to be eliminated in general applications, reducing friction power loss and sealing ring failure loss.

As shown in Figures 2 and 5, the top outer surface of the piston cylinder 8 is rotatably connected to a sleeve 24, and the inner wall of the sleeve 24 extends to form a plurality of extrusion rods 25. The interior of the piston cylinder 8 is provided with second movable grooves 3 corresponding to the positions of the plurality of extrusion rods 25, and the interior of the elastomer 713 is provided with extrusion grooves 4 corresponding to the moving trajectories of the plurality of extrusion rods 25. The shape of the plurality of extrusion grooves 4 is a crescent shape, and the side of the extrusion rod 25 close to the elastomer 713 points to the protruding position inside the elastomer 713.

When the X-shaped sealing ring 714 is worn for a period of time, the sleeve 24 is rotated to move the sleeve 24 with the extrusion rod 25 inside the second moving groove 3. When the sleeve 24 moves, it also moves inside the extrusion groove 4, and the side wall of the extrusion groove 4 in contact with the extrusion rod 25 gradually approaches the piston cylinder 8. When the extrusion rod 25 moves, it gradually squeezes the side wall of the extrusion groove 4, so that the elastomer 713 squeezes the X-shaped sealing ring 714. As the wear degree of the X-shaped sealing ring 714 gradually increases, the elastomer 713 squeezes the X-shaped sealing ring 714, so that the X-shaped sealing ring 714 always keeps in contact with the protective tube 711, so that the X-shaped sealing ring 714 can be used for a longer time, and the X-shaped sealing ring 714 does not need to be replaced when it encounters some wear. The extrusion rod 25 moves and gradually squeezes the extrusion groove 4, so that the raised position of the X-shaped sealing ring 714 always contacts with the protective tube 711.

As shown in Figure 7, multiple piston cylinders 8 extend toward the position of the sleeve 24 to form a second extension block 2. The interior of the sleeve 24 is provided with a third movable groove 5 for accommodating the movement of multiple second extension blocks 2. The interior of the multiple third movable grooves 5 is provided with a second spring 32 welded to the second extension block 2.

While the sleeve 24 rotates, the second extension block 2 rotates relatively inside the third movable groove 5, so that the second extension block 2 squeezes the second spring 32, making the sleeve 24 rotate more smoothly, and under the action of the second spring 32, the sleeve 24 can return to the original position with the squeezing rod 25, so that the squeezing rod 25 can be reused.

As shown in Figure 5, the multiple extension rods 26 extend from one side away from the X-shaped sealing ring 714 to form a first extension block 27, and the interior of the sleeve 24 is provided with first movable grooves 28 corresponding to the positions of the multiple first extension blocks 27, and the multiple first extension blocks 27 are slidably connected to the interior of the first movable grooves 28.

By moving the extending rod 26, the extending rod 26 moves downward with the first extending block 27, which facilitates the first extending block 27 to move inside the first moving groove 28. The first moving groove 28 restricts the movement of the extending rod 26 by restricting the first extending block 27, making the fixation of the sleeve 24 and the piston cover 721 more stable.

As shown in Figure 5, the bottom of the multiple extension rods 26 is welded with a first spring 29, and the multiple first springs 29 are in a natural extended state when the extension rods 26 do not move downward. The outer surface of the piston cover 721 extends to form an outer cylinder 30, and the outer cylinder 30 is located directly above the extension rod 26. A sealing gasket 6 is fixedly connected between the piston cover 721 and the outer cylinder 30. The inner bottom of the outer cylinder 30 corresponds to the position of the extension rod 26 and is provided with a plurality of circular holes 31 in a circular array with an angle of five degrees.

By opening a plurality of circular holes 31 at the bottom of the outer cylinder 30, the sleeve 24 can be fixed according to the X-shaped sealing ring 714 with different degrees of wear, and the extension rod 26 is inserted into the circular hole 31 to limit the movement of the piston gland 721, so that the piston gland 721 will not be detached when the device vibrates, and the sleeve 24 is always subjected to a counterclockwise force due to the squeezing of the second extension block 2 by the second spring 32, and the sleeve 24 is always squeezing the outer cylinder 30 counterclockwise through the extension rod 26, and the piston gland 721 rotates counterclockwise to strengthen the fixation with the piston cylinder 8, and again prevents the piston gland 721 from being detached when the device vibrates, and the sealing gasket 6 is used to strengthen the seal between the piston gland 721 and the piston cylinder 8 to prevent the liquid inside the piston cylinder 8 from flowing out when the rotating sleeve 24 adjusts the contact degree between the X-shaped sealing ring 714 and the protective tube 711.

Instructions for use: Water reaches the interior of the piston cylinder 8 through the water inlet pagoda head 18, and the upper piston rod 1 moves vertically downward under the action of the linear bearing 22. The contact pressure between the protective tube 711 and the X-shaped sealing ring 714 does not need to be too large. At the same time, the contact pressure is further reduced by the action of the working fluid pressure in the piston. The PTFE material is wear-resistant under low pressure, and the elastic force of the elastomer 713 has a self-repairing effect on the X-shaped sealing ring 714. After the wear degree of the X-shaped sealing ring 714 increases, the extrusion rod 25 extrude the elastomer 713 by rotating the sleeve 24, and the X-shaped sealing ring 714 is driven to extrude toward the protective tube 711, so that the X-shaped sealing ring 714 contacts the protective tube 711 again. As the X-shaped sealing ring 714 wears, the extrusion force of the elastomer 713 on the X-shaped sealing ring 714 gradually increases, and the sleeve 24 is fixed inside the different circular holes 31 by the extension rod 26, and the sleeve 24 extrudes the outer cylinder 30 counterclockwise, so that the piston gland 721 and the piston cylinder 8 are fixed more firmly.

The above is only a preferred specific implementation of the present invention; however, the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solution and its improved conception within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims (10)

1. Piston device, including piston cylinder (8), the inside top sliding connection of piston cylinder (8) has last piston rod (1), its characterized in that: the top of the piston cylinder (8) is provided with a sealing mechanism (7);

the sealing mechanism (7) comprises a fixing piece (72) fixed on the inner wall of the top of the piston cylinder (8), and a sealing piece (71) is fixed inside the fixing piece (72);

a fixing member (72), wherein the fixing member (72) fixes the sealing member (71) inside the piston cylinder (8) so that the upper piston rod (1) can reciprocate inside the piston cylinder (8);

the fixing piece (72) comprises a piston gland (721) fixedly connected to the top of the piston cylinder (8) through threads, and a sealing support (722) is arranged at the upper end of the interior of the piston cylinder (8);

-a seal (71), said seal (71) pressing against the upper piston rod (1) for increasing the tightness between the upper piston rod (1) and the piston cylinder (8).

The sealing member (71) comprises a protection pipe (711) sleeved on the outer surface of the upper piston rod (1), a lower conical pressing ring (712) is arranged at the top of the sealing support (722), an elastic body (713) is arranged on the outer surface of the lower conical pressing ring (712), an X-shaped sealing ring (714) is arranged between the elastic body (713) and the lower conical pressing ring (712), an upper conical pressing ring (715) is arranged on the inner surface of the upper half part of the X-shaped sealing ring (714), the upper conical pressing ring (715) and the lower conical pressing ring (712) are not in contact with the protection pipe (711), and the inner surface of the X-shaped sealing ring (714) is protruded and attached to the protection pipe (711).

2. A piston assembly as claimed in claim 1, wherein: the left side of piston cylinder (8) fixedly connected with goes out water pagoda head (19), the delivery port fixedly connected with flexible watering pipe (20) of play water pagoda head (19), the delivery port fixedly connected with rigidity watering pipe (21) of flexible watering pipe (20).

3. A piston assembly as claimed in claim 1, wherein: the top surface fixedly connected with uide bushing (23) of last piston rod (1), the below fixedly connected with linear bearing (22) of uide bushing (23), the central line coincidence of linear bearing (22), last piston rod (1) and piston cylinder (8), the material of X type sealing washer (714) and protection tube (711) is the PTFE material.

4. A piston assembly as claimed in claim 1, wherein: the bottom of piston cylinder (8) is through threaded connection having soil temperature regulating part (13), the inside top fixedly connected with of soil temperature regulating part (13) is piston (12) down, swing joint has first o type support (9) between piston (12) top and the piston cylinder (8) down, the below swing joint that first o type supported (9) has second o type support (11), swing joint has first o type circle (10) between first o type support (9) and second o type support (11), the bottom of soil temperature regulating part (13) is through threaded swing joint having into water pagoda head rotary cylinder (14), the bottom swing joint of water pagoda head rotary cylinder (14) has into water pagoda head (18), the inside bottom swing joint of water pagoda head rotary cylinder (14) has fourth o type support (17), the top swing joint that fourth o type supported (17) has third o type support (15), third o type support (15) and fourth o type support (17) between the second o type rotary cylinder (16).

5. A piston assembly as claimed in claim 1, wherein: the top surface of piston cylinder (8) rotates and is linked with sleeve (24), the inner wall extension of sleeve (24) is formed with a plurality of extrusion poles (25), second removal groove (3) have all been seted up to the inside position that corresponds a plurality of extrusion poles (25) of piston cylinder (8).

6. A piston assembly as set forth in claim 5 wherein: the extrusion grooves (4) are formed in the elastic body (713) corresponding to the movement tracks of the extrusion rods (25), the extrusion grooves (4) are semi-crescent, and one side, close to the elastic body (713), of the extrusion rods (25) points to the protruding position of the inner side of the elastic body (713).

7. A piston assembly as claimed in claim 1, wherein: the piston cylinders (8) extend to the positions of the sleeves (24) to form second extension blocks (2), third moving grooves (5) for accommodating the movement of the second extension blocks (2) are formed in the sleeves (24), and second springs (32) welded with the second extension blocks (2) are arranged in the third moving grooves (5).

8. A piston assembly as claimed in claim 1, wherein: the inside top sliding connection of sleeve (24) has extension pole (26), and a plurality of extension pole (26) are kept away from one side of X type sealing washer (714) and are all extended and form first extension piece (27), first removal groove (28) have all been seted up to the inside of sleeve (24) corresponding to the position of a plurality of first extension pieces (27), a plurality of first extension pieces (27) all sliding connection in the inside of first removal groove (28).

9. A piston assembly as set forth in claim 8 wherein: the bottoms of the plurality of the extending rods (26) are welded with first springs (29), and the plurality of the first springs (29) are in a natural extending state when the extending rods (26) do not move downwards.

10. A piston assembly as claimed in claim 1, wherein: the outer surface of the piston gland (721) extends to form an outer cylinder (30), the outer cylinder (30) is positioned right above the extending rod (26), a sealing gasket (6) is fixedly connected between the piston gland (721) and the outer cylinder (30), and a plurality of circular holes (31) which are in an annular array and have included angles of five degrees are formed in the inner bottom of the outer cylinder (30) at positions corresponding to the extending rod (26).