[0013] The drawings show the structure of the present invention, and the relevant details will be further described below in conjunction with the drawings. The pneumatic or hydraulic single-seat regulating valve includes a valve body 1, a valve cover 10 and a valve stem 11. The valve body 1 is provided with an inlet channel 33 and an outlet channel 16, and the inlet channel 33 and the outlet channel 16 pass through the center flow The central flow channel 22 is connected with a valve seat 23 and a valve disc 8 forming a sealing pair. The valve disc 8 is driven by the valve stem 11 to move up and down. The outer periphery of the central flow channel 22 corresponds to the upper part of the valve body 1. A first cavity, a second cavity, a third cavity, and a fourth cavity are sequentially arranged outside; the valve seat 23 can be moved up and down and arranged in the first cavity, and the upper end of the valve seat 23 can move out of the first cavity. A cavity, the lower end of the valve seat 23 is provided with a step 6, which separates the first cavity into a closed upper piston cavity 35 and a lower piston cavity 34. The upper piston cavity 35 is in communication with the inlet passage 33, and the lower piston cavity 34 and The outlet channel 16 is connected, the lower piston cavity 34 is connected to the outlet channel 16 through the right through hole 17, the step 6 at the lower end of the valve seat 23 is provided with a connecting pipe 24, the upper end of the connecting pipe 24 is connected to the upper piston cavity 35, and the connecting pipe 24 The lower end passes through the lower piston cavity 34 to communicate with the inlet passage 33. A first compression spring 21 is connected between the lower end of the valve seat 23 and the bottom of the first cavity; a scraper sleeve 20 is rotatably provided in the second cavity, and the scraper sleeve 20 is provided with The inner cavity is provided with a push rod 27 that can move up and down. The right side of the push rod 27 is provided with an upward driving slope 7 and a second compression is connected between the upper end of the push rod 27 and the upper end of the inner cavity of the scraping sleeve 20 The upper end of the inner cavity of the scraper sleeve 20 is connected with the outlet channel 16 and the lower end of the scraper sleeve 20 is provided with a right lower through hole 25. When the valve seat 23 moves down, the right lower through hole 25 connects the upper piston cavity 35 and the scraper sleeve 20 inner cavity, the upper part of the scraping sleeve 20 is equipped with a scraping head 26 that can move left and right. A return spring 36 is connected to the scraping head 26. The right end of the scraping head 26 can extend in the direction of the flow channel and penetrate through the sealing surface of the valve seat 23 The width of the scraper head 26 is provided with a drive slot 13 in the middle, the push rod 27 passes through the drive slot 13, and the drive slope 7 of the push rod 27 is in transmission cooperation with the drive slot 13; the third cavity is provided with a control sleeve 18 and a conversion sleeve 19 , The control sleeve 18 is fixedly arranged, the conversion sleeve 19 can be rotated and moved up and down in the control sleeve 18, the control sleeve 18 is provided with a spiral groove 31, the spiral groove 31 is provided with a push head 30, and the push head 30 is connected to the conversion sleeve 19, The inside of the conversion sleeve 19 is provided with a clamping block 5, the left side of the scraping sleeve 20 is provided with an extension part that extends into the third cavity, and the extension part is provided with a clamping slot 29, which slides axially with the clamping block 5, Circumferential transmission coordination; the fourth cavity is provided with a switching rod 32 that can float up and down, the upper end of the switching rod 32 and the upper end of the fourth cavity are connected with a third compression spring 4, and the upper end of the fourth cavity is connected to the outlet channel 16 is connected, the lower end of the fourth cavity is connected with the inlet channel 33, the valve body 1 is provided with an upper left through hole 3 that penetrates the outside, the fourth cavity and the top of the spiral groove 31, and is provided with a through hole 3 that penetrates the outside, fourth The lower left through hole 2 at the bottom of the cavity and the spiral groove 31, the switching rod 32 is provided with a first communication hole 37, a second communication hole 38, a third communication hole 39 and a fourth communication hole 40, when the switching rod 3 2 When moving up, the second connecting hole cooperates with the upper left through hole 3 to connect the outside world with the top of the spiral groove 31, and the fourth connecting hole cooperates with the lower left through hole 2 to connect the inlet channel with the bottom of the spiral groove 31. When the switch lever 32 moves down, the first The communication hole cooperates with the upper left through hole 3 to connect the outlet channel and the top of the spiral groove 31, and the third communication hole cooperates with the lower left through hole 2 to connect the outside world and the bottom of the spiral groove 31.
[0014] A driving device 15 is connected to the upper end of the valve stem 11, the driving device 15 is connected to the valve cover 10 through a bracket 12, and the driving device 15 is an air cylinder or a hydraulic cylinder.
[0015] A guide sleeve 9 is pressed between the valve cover 10 and the valve body 1, and the valve rod 11 passes through the guide sleeve 9.
[0016] The working process of the present invention: when the valve flap 8 is driven by the valve stem 11 to move down and approach the valve seat 23, when more solid particles are stuck at the sealing pair, the flow area between the valve flap 8 and the valve seat 23 decreases, and the outlet The pressure of the medium in the passage 16 drops, and the pressure of the medium in the inlet passage 33 increases. When the valve seat 23 receives the inlet passage 33 and flows into the upper piston cavity 35, the downward force of the medium is greater than the outlet passage 16 flows into the lower piston cavity 34 When the sum of the upward force of the medium and the upward force of the first compression spring 21, the valve seat 23 moves down, and the medium in the upper piston chamber 35 enters the lower right through hole 25 and pushes the push rod 27 to move upward, the push rod 27 The scraper head 26 is pushed to extend in the direction of the flow channel and penetrates the width of the sealing surface of the valve seat 23; at the same time, the upward force of the medium in the inlet passage 33 by the switching rod 32 is greater than the downward force of the third compression spring 4 and the outlet passage 16 The sum of the downward force of the inner medium, the inlet channel 33 is connected to the bottom of the spiral groove 31, and the top of the spiral groove 31 is connected to the atmosphere. The medium in the inlet channel 33 pushes the switching rod 32 upward, so that the medium in the inlet channel 33 enters the spiral groove 31 The bottom part pushes the push head 30 to move upward along the spiral groove 31. Because the push head 30 is fixedly connected to the conversion sleeve 19, and the conversion sleeve 19 is provided with a block extending into the slot 29, when the push head 30 rotates upward The conversion sleeve 19 is driven to rotate upward, and the scraper sleeve 20 is driven to rotate horizontally, that is, the scraper head 26 is driven to rotate along the circumferential direction of the sealing surface of the valve seat 23 to scrape off the solid particles stuck in the sealing pair.
[0017] When the solid particles at the seal pair are scraped off, the flow area between the valve flap 8 and the valve seat 23 increases, the medium pressure at the outlet channel 16 returns to the original pressure value, and the push rod 27 acts on the second compression spring 28 and the force and Under the action of the medium pressure in the outlet channel 16, the scraper head 26 returns to its original position under the action of the return spring 36. At the same time, the valve seat 23 is pushed upward by the medium in the lower piston chamber 34 and the first compression spring 21 moves upward. The sum of the force of the valve seat 23 is greater than the downward force of the medium in the upper piston chamber 35, and the valve seat 23 moves up to the original position; at the same time, the switching rod 32 receives the downward force of the third compression spring 4 and the outlet channel The sum of the downward force of the medium in 16 is greater than the upward force of the medium in the inlet channel 33 by the switching rod 32, the switching rod 32 moves down, the outlet channel 16 communicates with the top of the spiral groove 31, and the bottom of the spiral groove 31 communicates with the atmosphere, so the push head Under the action of the medium pressure in the outlet channel 16, the push head 30 rotates and moves down along the spiral groove 31, and finally drives the scraper sleeve 20 to rotate horizontally to the original position.
[0018] When the valve is about to be closed, the valve disc 8 moves down, and the sealing surface of the valve disc 8 presses against the sealing surface of the valve seat 23. At this time, the medium pressure in the outlet channel 16 drops, the valve seat 23 moves down, and the valve disc 8 moves down together. Because the upward force on the push rod 27 is greater than the downward force, the push rod 27 pushes the scraper 26 to move to the right and presses against the outer circle of the valve flap 8, which will not affect the sealing between the valve seat 23 and the valve flap 8.
[0019] In summary, the above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc., made within the spirit and principle of the present invention should be included in the protection scope of the present invention.