CN121363645B

CN121363645B - Ball valve capable of automatically controlling pressure and cutting off

Info

Publication number: CN121363645B
Application number: CN202511779148.4A
Authority: CN
Inventors: 蔡雷; 丁学峰; 李群; 李波
Original assignee: Yancheng Aokai Mingtong Valve Co ltd
Current assignee: Yancheng Aokai Mingtong Valve Co ltd
Priority date: 2025-11-28
Filing date: 2025-11-28
Publication date: 2026-04-17
Anticipated expiration: 2045-11-28
Also published as: CN121363645A

Abstract

The invention belongs to the technical field of valves, and particularly discloses a ball valve capable of automatically controlling pressure and cutting off, which comprises a valve shell, wherein a sealing cavity is formed in the middle of the inner part of the valve shell, a spherical valve core is arranged in the middle of the inner wall of the sealing cavity in a sealing and rotating manner, the middle part of the spherical valve core is in a penetrating opening shape, an indication groove is formed in the bottom of the valve shell, and a transmission cavity is formed in the inner part of the valve shell above the sealing cavity.

Description

Ball valve capable of automatically controlling pressure and cutting off

Technical Field

The invention relates to the technical field of valves, in particular to a ball valve capable of automatically controlling pressure and cutting off.

Background

Ball valves are usually valves in which a ball with a circular channel is used as an opening and closing element, and the ball rotates with a valve body to realize opening and closing actions. The opening and closing member of the ball valve is a sphere with a through hole and rotates around the axis vertical to the channel, thereby achieving the purpose of opening and closing the channel, and the medium is usually conveyed by a pipeline in industrial or civil infrastructure, wherein the pipeline is regulated due to pressure variation, and a regulating mechanism, especially a ball valve, is used in the pipeline for regulating the flow rate so as to ensure optimal working conditions and environmental safety.

When the ball valve is used in a pipeline, the existing ball valve is usually required to be manually controlled to be switched on or switched off, and when the pressure in the pipeline changes, the ball valve cannot immediately make corresponding regulation and control actions to cut off or open the ball valve automatically, so that the normal operation of pipeline conveying operation is affected to a certain extent.

Disclosure of Invention

The invention provides a ball valve capable of automatically controlling pressure and cutting off in order to solve the problems in the prior art.

The ball valve comprises a valve shell, wherein a sealing cavity is formed in the middle of the interior of the valve shell, a spherical valve core is arranged in the middle of the inner wall of the sealing cavity in a sealing and rotating mode, the middle part of the spherical valve core is in a penetrating opening shape, an indication groove is formed in the bottom of the valve shell, a transmission cavity is formed in the interior of the valve shell above the sealing cavity, a transmission assembly is arranged in the transmission cavity, and a drainage assembly is arranged in the valve shell;

the top and the bottom of spherical case all are fixed with the pivot, and the pivot that is located spherical case top is slided and is run through to the transmission intracavity portion, and the pivot that is located spherical case bottom is slided and is run through to the inside of instruction groove, and the inside of valve casing is provided with the spacing subassembly that triggers drainage subassembly work.

Preferably, the butt joint pipes communicated to the inside of the sealing cavity are fixed at the two ends of the valve casing, sealing nuts are arranged on the outer surfaces of the two butt joint pipes, an alarm lamp ring is fixed on the outer surface of the valve casing close to one side edge, a return pipe is fixed at the top of the valve casing, and a groove is formed in one side of the return pipe at the top of the valve casing.

Preferably, the transmission assembly comprises a hollow rubber ring, the hollow rubber ring is fixed between the inner walls of the valve housing and is close to one side of the sealing cavity, an oil cavity is formed in the valve housing, a bending runner penetrating to the inner part of the hollow rubber ring is formed in one end of the oil cavity, a guide groove is formed between the inner walls of the two sides of the transmission cavity and is close to the rear side edge, and one end of the guide groove penetrates to the other end of the oil cavity.

Preferably, a rack is arranged between the inner walls of the guide grooves in a sliding manner, a piston is arranged between the inner walls of the oil cavity in a sliding manner, one end of the rack is fixed on one side of the piston, sealing rings are arranged on the outer surfaces of the piston close to the edges of the two sides, and the outer surfaces of the two sealing rings are correspondingly in sliding sealing fit with the inner walls of the oil cavity.

Preferably, the inside of transmission chamber is provided with the transmission ring gear, and transmission ring gear and rack intermeshing, transmission ring gear are fixed in the pivot at spherical case top, and triangular opening has been seted up to the top of rack near piston one side, and inside bottom surface one side of instruction groove is provided with the arc scale strip, is provided with the pointer in the pivot of spherical case bottom, and the one end of pointer extends to the arc scale strip inboard.

Preferably, the spacing subassembly includes the insulation board, and regulation chamber has been seted up to the inside of valve casing, and the insulation board slides and is located between the inner wall in regulation chamber, and the top of insulation board is fixed with the lifter, and the top slip of lifter runs through to the inside of recess, and one side surface of lifter is close to top edge department and has seted up the notch.

Preferably, the bottom of insulation board is fixed with the location picture peg, and the bottom slip of location picture peg runs through to the inside of guide way, and the bottom block of location picture peg is inside the triangle mouth, and the top of insulation board is fixed with the spring, and the top of spring is fixed at the inside top surface of adjusting the chamber.

Preferably, the inside of insulation board is provided with the metal core, and the both ends of metal core correspond to run through to the both sides surface of insulation board, and the both sides inner wall of regulation chamber is close to bottom edge department and all is fixed with the copper paster, electric connection between two copper paster and the alarm lamp ring, and the both ends of metal core all correspond and laminate each other with the surface of copper paster.

Preferably, the drainage assembly comprises a bridging tube, the top of the valve casing is provided with a backflow hole, the backflow hole is positioned at the inner side of the backflow pipe, the bridging tube is positioned in the backflow hole, the outer surface of the bridging tube is in sliding sealing fit with the inner wall of the backflow hole, and the inner top surface of the valve casing is provided with an annular opening.

Preferably, the annular opening is located the outside in backward flow hole, a plurality of first grid mouths that run through to backward flow hole inside have been offered along circumferencial direction equidistance to the inner wall of annular opening near top edge department, a plurality of second grid mouths have been offered along circumferencial direction equidistance to the outer surface of bridge connection pipe near bottom edge department, a plurality of first grid mouths all correspond and communicate each other with the second grid mouth, the bottom of bridge connection pipe extends to a plurality of first grid mouths below, the side mouth that runs through to backward flow hole inside has been offered to one side inner wall in regulation chamber, the slip is provided with the connecting rod between the both sides inner wall of side mouth, the one end of connecting rod is fixed on the surface of bridge connection pipe, the other end is fixed on the surface of insulation board.

Compared with the prior art, the invention has the beneficial effects that:

1. According to the invention, the opening and closing of the valve can be automatically regulated according to the pressure change in the pipeline, when the pressure in the pipeline rises, the transmission assembly is triggered to work, so that the spherical valve core is turned on, and when the maximum pressure value of the valve is reached, the opening of the spherical valve core in the valve housing is in the maximum state, the limiting assembly is triggered to limit the transmission assembly, the opening degree is prevented from being reduced due to the fact that the spherical valve core continues to rotate, and meanwhile, the drainage assembly is conducted when the limiting assembly works, and the flow in the valve housing is drained;

2. When the transmission assembly works, after the pressure in the pipeline rises, the pressure in the pipeline can press the hollow rubber ring to the inner wall of the valve shell to press the hydraulic oil in the valve shell to the oil cavity, the piston is pushed to one side of the transmission cavity, and the rack is driven to slide during pushing, so that the transmission toothed ring is driven to drive the spherical valve core to rotate, the opening of the spherical valve core is gradually opened with the two butt joint pipes, and the valve shell is communicated;

3. When the limiting component works, when the pressure in the pipeline rises to the maximum passing pressure value of the valve, the opening degree between the opening of the spherical valve core and the two butt joint pipes is in the maximum state, the triangular opening on the rack slides to the bottom of the positioning inserting plate, and the positioning inserting plate is pressed down and inserted into the triangular opening under the action of the elastic force of the spring, so that the rack can be positioned;

4. When the drainage component works, the positioning plugboard can synchronously drive the bridging pipe to slide downwards when being inserted into the triangular opening in a sliding way, and a plurality of second grid openings positioned on the bridging pipe slide to the position opposite to the first grid openings at the moment, so that the second grid openings are communicated with the first grid openings, liquid in the valve casing is drained to the outside, and the internal pressure is prevented from rising continuously.

Drawings

FIG. 1 is a schematic top perspective view of a ball valve with self-controlling pressure cutoff function according to the present invention;

fig. 2 is a schematic bottom perspective view of a ball valve capable of automatically controlling pressure and cutting off according to the present invention;

FIG. 3 is a schematic perspective view of a sectional side view of a ball valve with self-controlled pressure cutoff according to the present invention;

FIG. 4 is a schematic view of a cross-sectional perspective structure of the other side of a ball valve capable of self-controlling pressure and cutting off;

FIG. 5 is a schematic cross-sectional perspective view of a transmission assembly in a ball valve with self-controlled pressure cutoff according to the present invention;

FIG. 6 is a schematic diagram showing a cross-sectional perspective structure of a limiting assembly and a drainage assembly in a ball valve capable of self-controlling pressure and cutting off;

FIG. 7 is a schematic top perspective view of a rack and a driving ring gear in a ball valve capable of self-controlling pressure and cutting off;

FIG. 8 is an enlarged view of a portion of the invention at A in FIG. 4;

Fig. 9 is an enlarged view of a portion of the invention at B in fig. 6.

The valve comprises a valve shell, a valve housing, a valve butt, a valve 3, a sealing nut, a valve return, a valve 5, a groove, a valve 6, an indication groove, a valve 7, an arc-shaped scale bar, a valve 8, a pointer, a valve 9, a rotary shaft, a valve 10, an alarm lamp ring, a valve 11, a sealing cavity, a valve 12, a spherical valve core, a valve 13, a hollow rubber ring, a valve 14, a transmission cavity, a valve 16, a bending runner, a valve 17, a transmission toothed ring, a valve 18, a rack, a valve 19, a guide groove, a valve 20, a triangular opening, a valve 21, a piston, a valve 22, a sealing ring, a valve 23, a positioning inserting plate, a valve 24, an adjusting cavity, a valve 25, a lifting rod, a valve 26, a spring, a valve 27, an insulating plate, a valve 28, a copper patch, a valve 29, a metal core, a valve 30, a reflux hole, a valve 31, a bridging tube, a valve 32, a side opening, a valve 33, a connecting rod, a 34, a notch, a 35, an annular opening, a 36, a first grid opening and a second grid opening.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Referring to fig. 1-9, the invention provides a technical scheme that the ball valve capable of automatically controlling pressure and cutting off comprises a valve shell 1, wherein a sealing cavity 11 is formed in the middle of the valve shell 1, a spherical valve core 12 is arranged in the middle of the inner wall of the sealing cavity 11 in a sealing and rotating manner, the middle part of the spherical valve core 12 is in a penetrating opening shape, an indication groove 6 is formed in the bottom of the valve shell 1, a transmission cavity 14 is formed in the valve shell 1 above the sealing cavity 11, a transmission component is arranged in the transmission cavity 14, and a drainage component is arranged in the valve shell 1;

The top and the bottom of spherical case 12 all are fixed with pivot 9, the pivot 9 that is located spherical case 12 top slides and runs through to drive chamber 14 inside, the pivot 9 that is located spherical case 12 bottom slides and runs through to the inside of instruction groove 6, the inside of valve casing 1 is provided with the spacing subassembly that triggers drainage subassembly work, the both ends of valve casing 1 all are fixed with the butt joint pipe 2 that feeds through to sealed chamber 11 inside, the surface of two butt joint pipes 2 all is provided with sealing nut 3, the surface of valve casing 1 is close to one side edge and is fixed with alarm lamp ring 10, the top of valve casing 1 is fixed with back flow 4, the top of valve casing 1 is located back flow 4 one side and sets up flutedly 5.

The effect that it reached is, be connected valve casing 1 through butt joint pipe 2 and the outside pipeline at both ends, valve casing 1 is in unoperated state when pressure is less in the pipeline, in the inside of valve casing 1 when pressure risees in the pipeline, can trigger drive assembly work, make spherical case 12 rotate, and then turn on valve casing 1, can further drive assembly work along with pressure rising, when reaching the maximum pressure value of valve, the opening degree of spherical case 12 in valve casing 1 is the biggest state this moment, can trigger spacing subassembly and carry out spacing to drive assembly this moment, prevent that spherical case 12 continues to rotate and cause the opening degree to diminish, spacing subassembly during operation can switch on the drainage subassembly, thereby lead to the flow of valve casing 1 inside, prevent that inside pressure from continuously rising and cause valve casing 1 both ends pressure differential great and cause the pipeline to shake.

As shown in fig. 2, fig. 3, fig. 4, fig. 5, fig. 7 and fig. 8, the transmission assembly comprises a hollow rubber ring 13, the hollow rubber ring 13 is fixed between the inner walls of the valve housing 1, and is close to one side of the sealing cavity 11, the oil cavity 15 is arranged in the valve housing 1, a bending runner 16 penetrating to the inside of the hollow rubber ring 13 is arranged at one end of the oil cavity 15, a guide groove 19 is arranged between the inner walls of the two sides of the transmission cavity 14 and is close to the rear side edge, one end of the guide groove 19 penetrates to the other end of the oil cavity 15, a rack 18 is slidably arranged between the inner walls of the guide groove 19, a piston 21 is slidably arranged between the inner walls of the oil cavity 15, one end of the rack 18 is fixed at one side of the piston 21, sealing rings 22 are respectively arranged at the edges of the outer surfaces of the piston 21 close to the two sides, the outer surfaces of the two sealing rings 22 are respectively in sliding and are in contact with the inner walls of the oil cavity 15, a transmission toothed ring 17 is arranged in the transmission cavity 14, the transmission toothed ring 17 is meshed with the rack 18, the transmission toothed ring 17 is fixed on a rotating shaft 9 positioned at the top of the spherical valve core 12, a triangular opening 20 is arranged at one side of the top of the rack 18, a pointer 7 is arranged at one side of the inner bottom surface of the guide groove 6 is arranged at one side of the bottom 7, the inner bottom surface 7 of the guide groove 6 is arranged at one side 7 of the spherical pointer 7 is positioned at the bottom 7 to the inner side of the spherical pointer 8 is arranged at the inner side 8, and is arranged at the inner end of the curved pointer 8 is arranged at the end of the curved pointer 8.

The hydraulic oil is fully filled in the hollow rubber ring 13 and the oil cavity 15 at the beginning, the piston 21 is positioned in the oil cavity 15 and is close to one side of the bending flow channel 16, the opening of the spherical valve core 12 is positioned in the sealing cavity 11, the opening is not communicated with the butt joint pipes 2 at two ends of the valve shell 1, when the pressure in the pipeline rises after the valve shell 1 is in butt joint, the pressure in the pipeline can press the hollow rubber ring 13 to the inner wall of the valve shell 1, when the hollow rubber ring 13 receives the pressure, the internal hydraulic oil can be extruded into the oil cavity 15, the piston 21 in the oil cavity 15 is pushed to the side of the transmission cavity 14, the rack 18 is driven to slide during pushing, the transmission toothed ring 17 is driven to drive the spherical valve core 12 to rotate, the opening of the spherical valve core 12 and the two butt joint pipes 2 are gradually opened, the valve shell 1 is enabled to be communicated, the pointer 8 is driven to synchronously rotate when the spherical valve core 12 is gradually rotated, one end of the rotary pointer 8 synchronously corresponds to the inner side of the arc scale bar 7, and the rotary position of the spherical valve core 12 can be judged by observing the relative position of one end of the pointer 8 and the inner side of the arc scale bar 7.

As shown in fig. 1, fig. 4, fig. 7 and fig. 8, spacing subassembly includes insulation board 27, regulation chamber 24 has been seted up to the inside of valve casing 1, insulation board 27 slides and is located between the inner wall of regulation chamber 24, the top of insulation board 27 is fixed with the lifting rod 25, the top of lifting rod 25 slides and runs through to the inside of recess 5, the one side surface of lifting rod 25 is close to top edge department and has seted up the notch 34, the bottom of insulation board 27 is fixed with location picture peg 23, the bottom of location picture peg 23 slides and runs through to the inside of guide way 19, and the bottom block of location picture peg 23 is inside triangle mouth 20, the top of insulation board 27 is fixed with spring 26, the top of spring 26 is fixed at the inside top of regulation chamber 24, the inside of insulation board 27 is provided with metal core 29, the both ends of metal core 29 correspond and run through to the both sides surface of insulation board 27, both sides inner wall of regulation chamber 24 are close to bottom edge and all are fixed with copper paster 28, electric connection between two copper paster 28 and the alarm lamp ring 10, the both ends of metal core 29 correspond and laminating each other with the surface of copper paster 28.

The effect that it reached is, when rack 18 slides, the laminating is slided with rack 18 top to the bottom of locating picture peg 23, when the pressure in the pipeline risees to the biggest pressure value that passes through of valve, the opening of spherical case 12 and the opening degree between two butt joint pipes 2 are the biggest state this moment, and the triangle mouth 20 on the rack 18 slides to locating picture peg 23 bottom this moment, insert the triangle mouth 20 inside with locating picture peg 23 under the elastic force effect of spring 26, can fix a position rack 18, prevent it to continue to drive transmission toothed ring 17 and spherical case 12 and continue to rotate, make the opening degree between spherical case 12 and the butt joint pipe 2 diminish, before locating picture peg 23 inserts the triangle mouth 20, metal core 29 that is located on insulating board 27 is located two copper paster 28 top, when picture peg 23 inserts the triangle mouth 20 inside, can drive insulating board 27 and slide downwards, the both ends of metal core 29 correspond and laminate each other with two copper paster 28 this moment, make the circuit switch on and open outside alarm lamp ring 10, it has reached the maximum to have reached to report to people to report to the police and point to prompt that the pressure inside valve casing 1 has reached the maintenance is convenient for people to overhaul.

As shown in fig. 3, 6 and 9, the drainage assembly includes a bridging tube 31, a backflow hole 30 is formed at the top of the valve housing 1, the backflow hole 30 is located at the inner side of the backflow tube 4, the bridging tube 31 is located inside the backflow hole 30, a ring-shaped opening 35 is formed on the inner top surface of the valve housing 1, the ring-shaped opening 35 is located at the outer side of the backflow hole 30, a plurality of first grid openings 36 penetrating into the backflow hole 30 are formed at the inner wall of the ring-shaped opening 35 near the top edge at equal intervals along the circumferential direction, a plurality of second grid openings 37 are formed at the outer surface of the bridging tube 31 near the bottom edge at equal intervals along the circumferential direction, the plurality of first grid openings 36 are correspondingly communicated with the second grid openings 37, the bottom of the bridging tube 31 extends to the lower side of the plurality of first grid openings 36, a side opening 32 penetrating into the backflow hole 30 is formed in one side inner wall of the adjusting cavity 24, a connecting rod 33 is slidably arranged between two side inner walls of the side opening 32, one end of the connecting rod 33 is fixed on the outer surface of the bridging tube 31, and the other end is fixed on the outer surface of the insulating plate 27.

The effect that this reaches is, when locating picture peg 23 does not insert inside triangular mouth 20, a plurality of second grid mouths 37 on the bridge pipe 31 all are located first grid mouths 36 top, slide sealed laminating is sealed first grid mouths 36 through between the surface of bridge pipe 31 and the back flow hole 30 inner wall in back flow hole 30 inside, when locating picture peg 23 slides down and inserts triangular mouth 20, can drive bridge pipe 31 simultaneously and slide down, a plurality of second grid mouths 37 that are located on bridge pipe 31 are located the department that is opposite to first grid mouths 36 this moment, at this moment second grid mouths 37 and first grid mouths 36 intercommunication each other, fluid that is located valve casing 1 inside can get into bridge pipe 31 through second grid mouths 37 and first grid mouths 36, then discharge from back flow pipe 4, prevent valve body 1 internal pressure from continuously rising, make valve both ends pressure differential grow and cause the tremble to the pipeline.

Working principle: when the device is used, the valve shell 1 is connected with an external pipeline through the butt joint pipes 2 at two ends, hydraulic oil is fully filled in the hollow rubber ring 13 and the oil cavity 15 in the beginning, the piston 21 is positioned in the oil cavity 15 and is close to one side of the bending flow channel 16, the opening of the spherical valve core 12 is positioned in the sealing cavity 11 and is not communicated with the butt joint pipes 2 at two ends of the valve shell 1, when the internal pressure of the pipeline rises after the valve shell 1 is in butt joint, the pressure in the pipeline can press the hollow rubber ring 13 towards the inner wall of the valve shell 1, when the pressure of the hollow rubber ring 13 is increased, the internal hydraulic oil can be extruded towards the oil cavity 15, the piston 21 in the oil cavity 15 is pushed towards the transmission cavity 14, the rack 18 is driven to slide in the pushing process, the transmission toothed ring 17 is driven to drive the spherical valve core 12 to rotate, the opening of the spherical valve core 12 and the two butt joint pipes 2 are gradually opened, the valve shell 1 is communicated, and when the rack 18 slides, the bottom of the locating plugboard 23 is in sliding fit with the top of the rack 18, when the pressure in a pipeline rises to the maximum passing pressure value of a valve, at the moment, the opening of the spherical valve core 12 and the opening between the two butt joint pipes 2 are in the maximum state, the triangular opening 20 on the rack 18 slides to the bottom of the locating plugboard 23, the locating plugboard 23 is pressed down and inserted into the triangular opening 20 under the action of the elastic force of the spring 26, the rack 18 can be located, the transmission toothed ring 17 and the spherical valve core 12 are prevented from being continuously driven to rotate, the opening degree between the spherical valve core 12 and the butt joint pipes 2 is reduced, the insulating plate 27 is driven to slide downwards when the locating plugboard 23 slides downwards, at the moment, the two ends of the metal core 29 are correspondingly in mutual fit with the two copper patches 28, the circuit is conducted, the external alarm lamp ring 10 is opened, and when the locating plugboard 23 is not inserted into the triangular opening 20, the second grid openings 37 on the bridging tube 31 are all located above the first grid openings 36, the first grid openings 36 are sealed in the interior of the backflow hole 30 by sliding sealing fit between the outer surface of the bridging tube 31 and the inner wall of the backflow hole 30, when the positioning plug plate 23 is inserted into the triangular opening 20 in a sliding mode, the bridging tube 31 is synchronously driven to slide downwards, the second grid openings 37 on the bridging tube 31 slide to the position opposite to the first grid openings 36, at the moment, the second grid openings 37 are communicated with the first grid openings 36, fluid in the valve housing 1 can enter the bridging tube 31 through the second grid openings 37 and the first grid openings 36 and then is discharged from the backflow tube 4, and the pressure in the valve body 1 is prevented from rising continuously, so that the pressure difference between two ends of the valve is increased, and the pipe is caused to shake.

Although the present invention has been described with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described, or equivalents may be substituted for elements thereof, and any modifications, equivalents, improvements and changes may be made without departing from the spirit and principles of the present invention.

Claims

1. The utility model provides a ball valve that can control by oneself presses and cuts, its characterized in that, including valve casing (1), sealed chamber (11) have been seted up to the inside department that lies in the centre of valve casing (1), sealed rotation is provided with spherical case (12) in the middle of the inner wall of sealed chamber (11), the middle part of spherical case (12) is the through-opening form, indication groove (6) have been seted up to the bottom of valve casing (1), transmission chamber (14) have been seted up to the inside that lies in sealed chamber (11) top of valve casing (1), transmission chamber (14) inside is provided with drive assembly, the inside of valve casing (1) is provided with drainage assembly;

The top and the bottom of the spherical valve core (12) are both fixed with rotating shafts (9), the rotating shafts (9) positioned at the top of the spherical valve core (12) penetrate through the inside of the transmission cavity (14) in a sliding manner, the rotating shafts (9) positioned at the bottom of the spherical valve core (12) penetrate through the inside of the indication groove (6) in a sliding manner, and a limiting assembly for triggering the drainage assembly to work is arranged in the valve housing (1);

The transmission assembly comprises a hollow rubber ring (13), the hollow rubber ring (13) is fixed between the inner walls of the valve housing (1), one side close to the sealing cavity (11) is provided with an oil cavity (15), one end of the oil cavity (15) is provided with a bending flow passage (16) penetrating into the hollow rubber ring (13), a guide groove (19) is provided between the inner walls of the two sides of the transmission cavity (14) close to the rear side edge, one end of the guide groove (19) penetrates into the other end of the oil cavity (15), a rack (18) is slidably arranged between the inner walls of the guide groove (19), one end of the rack (18) is fixedly arranged on one side of the piston (21), the outer surfaces of the piston (21) are provided with sealing rings (22) close to the edges of the two sides, the outer surfaces of the two sealing rings (22) are correspondingly in sliding sealing fit with the inner walls of the oil cavity (15), the transmission cavity (14) is internally provided with a transmission toothed ring (17), the transmission toothed ring (17) is slidably arranged between the inner walls of the guide groove (19), one end of the guide groove (19) is fixedly provided with a piston (21) between the inner walls of the piston (21), one end of the rack (21) is fixedly arranged on one side of the piston (21), and the other end of the piston (12) is fixedly meshed with the spherical valve core (12), triangular openings (20) are formed in the top of the rack (18) close to one side of the piston (21), arc-shaped scale bars (7) are arranged on one side of the inner bottom surface of the indication groove (6), pointers (8) are arranged on rotating shafts (9) arranged at the bottoms of the spherical valve cores (12), and one ends of the pointers (8) extend to the inner sides of the arc-shaped scale bars (7).

2. The ball valve capable of automatically controlling pressure and cutting off according to claim 1, wherein two ends of the valve housing (1) are respectively fixed with a butt joint pipe (2) communicated to the inside of the sealing cavity (11), the outer surfaces of the two butt joint pipes (2) are respectively provided with a sealing nut (3), an alarm lamp ring (10) is fixed on the outer surface of the valve housing (1) close to one side edge, a return pipe (4) is fixed on the top of the valve housing (1), and a groove (5) is formed in one side of the return pipe (4) at the top of the valve housing (1).

3. The ball valve capable of automatically controlling pressure and cutting off according to claim 2, wherein the limiting component comprises an insulating plate (27), an adjusting cavity (24) is formed in the valve housing (1), the insulating plate (27) is slidably located between inner walls of the adjusting cavity (24), a lifting rod (25) is fixed to the top of the insulating plate (27), the top of the lifting rod (25) slidably penetrates into the groove (5), and a notch (34) is formed in the outer surface of one side of the lifting rod (25) close to the top edge.

4. The ball valve capable of automatically controlling pressure and cutting off according to claim 3, wherein a positioning insertion plate (23) is fixed at the bottom of the insulating plate (27), the bottom of the positioning insertion plate (23) penetrates through the guide groove (19) in a sliding mode, the bottom of the positioning insertion plate (23) is clamped inside the triangular opening (20), a spring (26) is fixed at the top of the insulating plate (27), and the top of the spring (26) is fixed on the inner top surface of the adjusting cavity (24).

5. The ball valve capable of automatically controlling pressure and cutting off according to claim 4, wherein a metal core (29) is arranged in the insulating plate (27), two ends of the metal core (29) correspondingly penetrate through two outer surfaces of the insulating plate (27), copper patches (28) are fixed on two inner walls of the two sides of the adjusting cavity (24) close to the bottom edge, the two copper patches (28) are electrically connected with the alarm lamp ring (10), and two ends of the metal core (29) are correspondingly attached to the outer surfaces of the copper patches (28).

6. The ball valve capable of automatically controlling pressure and cutting off according to claim 5, wherein the drainage component comprises a bridging tube (31), a backflow hole (30) is formed in the top of the valve casing (1), the backflow hole (30) is located at the inner side of the backflow tube (4), the bridging tube (31) is located inside the backflow hole (30), the outer surface of the bridging tube (31) is in sliding sealing fit with the inner wall of the backflow hole (30), and an annular opening (35) is formed in the inner top surface of the valve casing (1).

7. The ball valve capable of self-controlling pressure and cutting off according to claim 6, wherein the annular opening (35) is located at the outer side of the backflow hole (30), a plurality of first grid openings (36) penetrating into the backflow hole (30) are formed in the position, close to the top edge, of the inner wall of the annular opening (35) at equal intervals along the circumferential direction, a plurality of second grid openings (37) are formed in the position, close to the bottom edge, of the outer surface of the bridging tube (31) at equal intervals along the circumferential direction, the first grid openings (36) are correspondingly communicated with the second grid openings (37), the bottom of the bridging tube (31) extends to the position below the first grid openings (36), a side opening (32) penetrating into the backflow hole (30) is formed in the inner wall on one side of the adjusting cavity (24), a connecting rod (33) is slidably arranged between the inner walls on two sides of the side opening (32), one end of the connecting rod (33) is fixed on the outer surface of the bridging tube (31), and the other end of the connecting rod (33) is fixed on the outer surface of the insulating plate (27).