CN214304614U

CN214304614U - Pilot-operated proportional pressure reducing valve

Info

Publication number: CN214304614U
Application number: CN202120234049.9U
Authority: CN
Inventors: 宋兆柱
Original assignee: Beijing Hongji Shida Hydraulic Co ltd
Current assignee: Beijing Hongji Shida Hydraulic Co ltd
Priority date: 2021-01-27
Filing date: 2021-01-27
Publication date: 2021-09-28
Anticipated expiration: 2031-01-27

Abstract

The application relates to the field of pressure reducing valves, in particular to a pilot type proportional pressure reducing valve, which has the technical scheme that: the oil-saving valve comprises an outer valve body, wherein a liquid inlet cavity, a liquid outlet cavity and a pressure relief long hole communicated with an oil tank are formed in the outer valve body, a valve core cover is arranged on the outer valve body, a main piston is arranged in the outer valve body, a liquid outlet pressure cavity is formed by the end face, close to the liquid inlet cavity, of the main piston and the outer valve body, and a liquid inlet pressure cavity is formed by the end face, far away from the liquid outlet pressure cavity, of the main piston and the valve core cover; a first communicating hole for communicating the liquid outlet cavity with the liquid outlet pressure cavity is formed in the main piston, a second communicating hole for communicating the liquid inlet cavity with the liquid inlet pressure cavity is formed in the main piston, and the main piston is connected with a stabilizing valve; the outer valve body is provided with a pilot valve for controlling the liquid pressure in the liquid inlet pressure cavity. The oil pressure at the oil outlet of the pilot type pressure reducing valve is gradually increased, the impact of components in the hydraulic oil circuit is reduced, and the risk of damage of the components in the hydraulic oil circuit is reduced.

Description

Pilot-operated proportional pressure reducing valve

Technical Field

The application relates to the field of pressure reducing valves, in particular to a pilot type proportional pressure reducing valve.

Background

At present, a pressure reducing valve is a pressure control valve which reduces an inlet pressure to a certain required outlet pressure through regulation and enables the outlet pressure of the pressure reducing valve to maintain stable by means of energy of hydraulic oil.

In the related art, chinese patent publication No. CN104061353A discloses a pilot-operated pressure reducing valve, which includes a pressure regulating hand wheel, a spring and a valve cover, wherein the spring includes a pressure regulating spring and a main valve spring, a regulating screw is mounted on the pressure regulating hand wheel, the regulating screw is mounted on the valve cover, the pressure regulating spring is disposed in the valve cover, the pressure regulating spring is connected to one end of the pilot valve, the other end of the pilot valve is fixed with a pilot valve core, the pilot valve core is fixed on a pilot valve seat, a remote control port is disposed at the tail end of the pilot valve seat, an oil drainage port is disposed at the lower end of the pilot valve seat, a valve body is fixed at the lower end of the valve cover, a main valve spring is disposed in the valve body, an oil inlet is disposed at the lower end of the main valve spring, a main valve core is disposed on the oil inlet, a pressure reducing port is disposed on the main valve core, an oil outlet is disposed at one side of the pressure reducing port, a damping hole is disposed at one side of the lower end of the main valve core, and an end cover is disposed at the bottom of the main valve core.

In view of the above-mentioned related art solutions, the inventors found that: when the pilot type reducing valve is started to work, the pressure of the oil inlet is increased sharply, and the pressure of the oil outlet does not reach the required pressure, so that the pressure of the whole hydraulic oil way is increased sharply, components in the oil way are impacted, and the risk of damage to the components in the oil way is increased.

SUMMERY OF THE UTILITY MODEL

In order to make the oil pressure of pilot-operated formula relief pressure valve delivery port department increase gradually, reduce the impact of components and parts in the hydraulic pressure oil circuit, and then reduce the risk of components and parts damage in the hydraulic pressure oil circuit, this application provides pilot-operated formula proportional pressure relief valve.

The application provides a guide's formula proportional pressure reducing valve adopts following technical scheme:

the pilot-operated proportional pressure reducing valve comprises an outer valve body, wherein a liquid inlet cavity, a liquid outlet cavity and a pressure relief long hole communicated with an oil tank are formed in the outer valve body; a first communicating hole for communicating the liquid outlet cavity with the liquid outlet pressure cavity is formed in the main piston, a second communicating hole for communicating the liquid inlet cavity with the liquid inlet pressure cavity is formed in the main piston, and a stabilizing valve for stabilizing the pressure of liquid flowing into the liquid inlet pressure cavity is connected to the end face, far away from the liquid outlet pressure cavity, of the main piston; the outer valve body is provided with a pilot valve for controlling the liquid pressure in the liquid inlet pressure cavity.

By adopting the technical scheme, when the pilot type pressure reducing valve is started, the liquid pressure in the liquid inlet cavity is suddenly increased, the high-pressure liquid flows through the second communication hole and passes through the stabilizing effect of the stabilizing valve, so that the liquid pressure in the liquid inlet pressure cavity is gradually increased, the liquid pressure in the liquid outlet pressure cavity cannot resist the high-pressure liquid in the liquid outlet pressure cavity due to the small pressure of the liquid outlet cavity, the high-pressure liquid in the liquid outlet pressure cavity pushes the main piston to move to communicate the liquid inlet cavity with the liquid outlet cavity, the high-pressure liquid flows into and out of the liquid cavity from the liquid inlet cavity, the liquid pressure in the liquid outlet cavity is increased, the liquid pressure in the liquid outlet pressure cavity is increased, the main piston is pushed to disconnect the liquid inlet cavity from the liquid outlet cavity, the liquid pressure in the liquid outlet cavity is stopped to be increased, and the liquid pressure in the liquid outlet cavity is determined by the liquid pressure in the liquid inlet pressure cavity. The stabilizing valve gradually raises the liquid pressure in the liquid inlet pressure cavity and further gradually raises the liquid pressure in the liquid outlet cavity, rather than as the liquid pressure in the liquid inlet cavity is increased suddenly, so that the pressure of a hydraulic oil circuit connected with the pilot type pressure reducing valve can be gradually raised, and further the risk of damage of elements in the hydraulic oil circuit is reduced.

Preferably, the pilot valve includes a pilot valve body, the pilot valve body is arranged on the outer valve body, a pilot fixed valve core with two through end faces is connected inside the pilot valve body, a pilot movable valve core capable of plugging the pilot fixed valve core is matched with a shaft hole inside the pilot valve body, a space enclosed by an end face of the pilot fixed valve core far away from the pilot movable valve core and the pilot valve body is communicated with the liquid inlet pressure cavity, a region enclosed by the pilot movable valve core, the pilot fixed valve core and the pilot valve body is communicated with the oil tank, and an electromagnetic coil capable of controlling a force enabling the pilot movable valve core to abut against the pilot fixed valve core is arranged on the pilot valve body.

By adopting the technical scheme, when the pilot-operated type pressure reducing valve is used, the oil pressure of the liquid inlet cavity is increased, the oil pressure of the liquid inlet pressure cavity is gradually increased, the oil pressure at one end, away from the pilot-operated valve core, of the pilot-operated valve core is gradually increased, further, third thrust moving towards the direction away from the pilot-operated valve core is generated on the pilot-operated valve core, the electromagnetic coil works, fourth thrust resisting the separation of the pilot-operated valve core and the pilot-operated valve core is given to the pilot-operated valve core, when the third thrust is gradually increased until the third thrust is slightly larger than the fourth thrust, the pilot-operated valve core is separated from the pilot-operated valve core, and liquid at one end, away from the pilot-operated valve core, of the pilot-operated valve core can flow through the interior of the pilot-operated valve core and flow into the oil tank, so as to be reduced in pressure. Therefore, the pressure of the liquid in the liquid inlet pressure cavity is always maintained at the pressure required by people, and the design of the electromagnetic coil enables people to control the magnitude of the fourth thrust by controlling the electromagnetic coil, so that the pressure of the liquid in the liquid inlet pressure cavity is controlled, and the oil pressure in the liquid outlet cavity is controlled.

Preferably, the solenoid is detachably connected to the pilot valve body.

Through adopting above-mentioned technical scheme, compare in through the pilot-operated case of spring control, such design makes solenoid can be more convenient pull down or install from the pilot-operated valve body, and then not only conveniently change solenoid when solenoid damages, conveniently change the solenoid of multiple model moreover, and then make the scope of fourth thrust size wider, and then make pilot-operated relief pressure valve application scope wider.

Preferably, the pilot valve body is made of an aluminum material.

Through adopting above-mentioned technical scheme, compare in the structure that pilot valve body made for the plastics material, the structural strength of aluminium system material is higher, and then makes the pilot valve body not fragile more to the life of pilot valve has been prolonged.

Preferably, the peripheral surface of the pilot valve core is provided with a flat pressing groove which is communicated with two end surfaces of the pilot valve core.

By adopting the technical scheme, when the pilot operated valve core moves in the pilot valve body, the liquid at one end of the pilot operated valve core can flow to the other end through the flat pressure groove, so that the pilot operated valve core can smoothly move in the pilot valve body.

Preferably, the peripheral surface of the main piston is wrapped with a valve core cylinder, the valve core cylinder is matched with an outer valve body shaft hole, a liquid inlet hole communicated with the inside of the valve core cylinder and the liquid inlet cavity, a liquid outlet hole communicated with the inside of the valve core cylinder and the liquid outlet cavity and a pressure relief hole communicated with the inside of the valve core cylinder and the pressure relief long hole are formed in the valve core cylinder, the end surface, away from the liquid inlet hole, of the valve core cylinder is abutted to a valve core cover, and the valve core cover is in threaded connection with the outer valve body.

Through adopting above-mentioned technical scheme, compare in the too much hole of external valve body internal processing, the setting up of a case makes the inside too much accurate hole of need not to process of outer valve body, and can realize the function to the processing of a case section of thick bamboo, and a case section of thick bamboo is compared in outer valve body and easily processes, makes the pilot-operated formula relief pressure valve change in processing like this to the production efficiency of pilot-operated formula relief pressure valve has been improved.

Preferably, the pilot valve body is provided with an external plug capable of communicating the inside and the outside of the pilot valve body.

Through adopting above-mentioned technical scheme, people can be through external end cap with the inside and oil circuit intercommunication of pilot valve body, and then make the pilot valve can control partial oil circuit, the connector has been reserved to setting up to more oil circuits of pilot valve control or components and parts of external end cap, makes the pilot-operated formula relief pressure valve have better expansibility.

Preferably, the outer valve body is internally provided with a one-way hole for communicating the liquid inlet cavity with the liquid outlet cavity, and the outer valve body is in threaded connection with a one-way valve which enables liquid in the one-way hole to flow from one end close to the liquid outlet cavity to one end close to the liquid inlet cavity.

By adopting the technical scheme, after the pilot type pressure reducing valve is connected to the hydraulic oil circuit, the hydraulic oil circuit stops working, the oil pressure of the liquid inlet cavity is almost zero, the oil pressure of the liquid outlet cavity is still the pressure during working, the pressure of the liquid outlet cavity is greater than that of the liquid inlet cavity, the one-way valve is conducted, the pressure of the liquid cavity is released, and then the pressure of the hydraulic oil circuit behind the liquid outlet of the pilot type pressure reducing valve is released. The design of the one-way valve enables the hydraulic oil circuit to automatically release pressure, so that all components of the oil circuit are in a light load state, and the hydraulic oil circuit is protected.

In summary, the present application has the following technical effects:

1. by arranging the stabilizing valve, the oil pressure in the liquid inlet pressure cavity can not be increased rapidly, so that the oil pressure in the liquid outlet cavity is gradually increased, and the impact of components in the hydraulic oil circuit is reduced, thereby protecting the hydraulic oil circuit;

2. through having set up solenoid, make people conveniently change the oil pressure of entering hydraulic pressure intracavity according to the needs of hydraulic pressure oil circuit to make the application range of guide's formula relief pressure valve more extensive.

Drawings

FIG. 1 is a cross-sectional view of a pilot operated pressure relief valve in an embodiment of the present application;

fig. 2 is a partially enlarged view of a portion a in fig. 1.

In the figure, 1, an outer valve body; 11. a liquid inlet cavity; 12. a liquid outlet cavity; 13. a spool bore; 14. a one-way hole; 15. a first pilot connection hole; 16. a first pilot pressure relief vent; 17. a pressure relief slot hole; 2. a valve core assembly; 21. a valve cartridge barrel; 211. a liquid inlet hole; 212. a liquid outlet hole; 213. a pressure relief vent; 214. a pressure relief groove; 215. a first spring groove; 216. a pilot hole; 22. a primary piston; 221. a liquid passing groove; 222. a first communication hole; 223. a second communication hole; 224. connecting holes; 23. a valve core cover; 231. a second spring groove; 232. a pressure tank; 24. a first elastic member; 25. a first spring housing; 26. a second spring housing; 3. a pilot valve; 31. a pilot valve body; 311. firstly, guiding a groove; 312. a second pilot connection hole; 313. a second pilot pressure relief vent; 32. a pilot fixed valve core; 321. a pilot control hole; 33. a pilot operated valve spool; 331. a flat pressing groove; 34. a conical plug; 35. a plug is externally connected; 36. a pilot liquid inlet zone; 37. firstly, leading out a liquid area; 38. an electromagnetic coil; 4. a stabilizing valve; 41. stabilizing the valve body; 411. a stabilizing slot; 412. a pilot liquid inlet hole; 413. a third spring groove; 414. a pilot liquid through hole; 42. stabilizing the valve core; 421. a fourth spring groove; 422. a damping hole; 43. a second elastic member; 44. a stabilizing plug; 5. a one-way valve; 6. a liquid inlet pressure cavity; 7. and a liquid outlet pressure cavity.

Detailed Description

The present application is described in further detail below with reference to the attached drawings.

Referring to fig. 1, the application provides guide's formula proportional pressure reducing valve, including outer valve body 1, case subassembly 2 and pilot valve 3, feed liquor chamber 11 and play sap cavity 12 have been seted up to outer valve body 1 is inside, feed liquor chamber 11 all communicates with outer valve body 1 outside with play sap cavity 12, case subassembly 2 sets up the break-make in outer valve body 1 is inside and can control feed liquor chamber 11 and play sap cavity 12, pilot valve 3 sets up on outer valve body 1.

The valve core assembly 2 comprises a valve core cylinder 21 and a main piston 22, a valve core hole 13 matched with the valve core cylinder 21 is formed in the outer valve body 1, the valve core hole 13 is communicated with the liquid inlet cavity 11 and the liquid outlet cavity 12, one end, far away from the liquid inlet cavity 11, of the valve core hole 13 close to the liquid outlet cavity 12 is communicated with the outer space of the outer valve body 1, a valve core cover 23 is arranged on the outer valve body 1, one end of the valve core cover 23 extends into the valve core hole 13 and is in threaded connection with the inner wall of the valve core hole 13, the end face, extending into the valve core hole 13, of the valve core cover 23 is abutted against one end of the valve core cylinder 21, and one end, far away from the valve core cover 23, of the valve core cylinder 21 is abutted against the bottom of the valve core hole 13. The valve core cylinder 21 is provided with a liquid inlet hole 211 which penetrates through the valve core cylinder 21 and communicates the interior of the valve core cylinder 21 with the liquid inlet cavity 11; the valve core cylinder 21 is provided with a liquid outlet 212 which penetrates through the valve core cylinder 21 and is communicated with the interior of the valve core cylinder 21 and the liquid outlet cavity 12; the peripheral surface of the valve core cylinder 21 is provided with a pressure relief hole 213 penetrating through the valve core cylinder 21, the pressure relief hole 213 is positioned at one side of the liquid outlet hole 212 close to the valve core cover 23, the outer cylinder wall of the valve core cylinder 21 is provided with a pressure relief groove 214, the pressure relief groove 214 is arranged corresponding to the pressure relief hole 213, the inside of the pressure relief groove 214 is communicated with the pressure relief hole 213, and the outer valve body 1 is provided with a pressure relief long hole 17 for communicating the inside of the pressure relief groove 214 with the outside of the outer valve body 1. The main piston 22 is matched with the shaft hole of the inner wall of the valve core cylinder 21, and the peripheral surface of the main piston 22 is provided with a liquid passing groove 221 which can be communicated with the liquid inlet hole 211 and the liquid outlet hole 212 or the liquid outlet hole 212 and the pressure relief hole 213.

When the pilot type pressure reducing valve is used, high-pressure liquid enters the liquid inlet cavity 11, the high-pressure liquid flows into the valve core cylinder 21 from the liquid inlet cavity 11 through the liquid inlet hole 211, when the main piston 22 moves towards the direction close to the bottom of the valve core hole 13, the liquid passing groove 221 is communicated with the liquid inlet hole 211 and the liquid outlet hole 212, the high-pressure liquid flows into the liquid outlet cavity 12 through the inside of the liquid passing groove 221 and the liquid outlet hole 212, and the liquid pressure in the liquid outlet cavity 12 is increased; when the liquid pressure in the liquid outlet chamber 12 increases to the required pressure, the main piston 22 moves towards one end close to the valve core cover 23, so that the liquid inlet hole 211 is disconnected from the liquid outlet hole 212, and the liquid in the liquid outlet chamber 12 maintains the required pressure; when the pressure of the liquid outlet cavity 12 is too high, the main piston 22 moves towards the direction close to the valve core cover 23, so that the liquid passing groove 221 communicates the liquid outlet hole 212 with the pressure relief hole 213, the too-high pressure liquid of the liquid outlet cavity 12 flows through the liquid outlet hole 212 and flows into the pressure relief hole 213 through the liquid passing groove 221, the too-high pressure liquid continuously flows through the pressure relief groove 214 and flows out of the outer valve body 1 from the pressure relief long hole 17, the pressure relief long hole 17 is communicated with the oil tank, and the too-high pressure liquid finally flows into the oil tank, so that the liquid pressure of the liquid outlet cavity 12 is reduced, and the pressure of the liquid outlet cavity 12 is maintained at the required pressure. Compare in processing too much hole to outer valve body 1 inside, the setting up of a valve core section of thick bamboo 21 makes outer valve body 1 inside need not to process too much precision hole, and can realize the function to a valve core section of thick bamboo 21 processing, and a valve core section of thick bamboo 21 is compared in outer valve body 1 and easily processes, makes the leading formula relief pressure valve change in processing like this to the production efficiency of leading formula relief pressure valve has been improved.

Referring to fig. 1, the area enclosed by the end surface of the main piston 22 far away from the valve core cover 23, the hole bottom of the valve core hole 13 and the inner wall of the valve core cylinder 21 forms the liquid outlet pressure chamber 7. A first communication hole 222 for communicating the liquid outlet pressure cavity 7 and the liquid passing groove 221 is formed in the end surface of the main piston 22 far away from the valve core cover 23 and facing the interior of the main piston 22; the end surface of the main piston 22 close to the valve core cover 23 is opened with a connecting hole 224 towards the interior of the main piston 22, the connecting hole 224 is opened coaxially with the main piston 22, the peripheral surface of the main piston 22 is opened with a second communicating hole 223 capable of communicating the liquid inlet hole 211 with the connecting hole 224, and the orifice of the second communicating hole 223 positioned on the peripheral surface of the main piston 22 is positioned at one side of the overflowed liquid groove 221 far away from the valve core cover 23.

Referring to fig. 1 and 2, a stabilizing valve 4 is disposed at an end of the main piston 22 away from the outlet pressure chamber 7, a first spring sleeve 25 is disposed on an end surface of the main piston 22 away from the outlet pressure chamber 7, the first spring sleeve 25 is wrapped around the stabilizing valve 4, a first spring slot 215 capable of accommodating the first spring sleeve 25 is disposed on an end surface of the main piston 22 away from the outlet pressure chamber 7, an end surface of the first spring sleeve 25 away from the spool cover 23 is capable of abutting against a bottom of a first spring slot 215, a first elastic member 24 is abutted against the first spring sleeve 25, the first elastic member 24 is wrapped around the stabilizing valve 4, a second spring sleeve 26 is abutted against an end of the first elastic member 24 away from the first spring sleeve 25, a second spring slot 231 capable of accommodating the stabilizing valve 4, the second spring sleeve 26 and the first elastic member 24 is disposed on an end surface of the spool cover 23 close to the main piston 22, the second spring sleeve 26 abuts against a bottom of the second spring slot 231, the bottom of the second spring groove 231 is provided with a pressure groove 232 capable of accommodating the stabilizing valve 4, and the groove wall of the pressure groove 232, the groove wall of the first spring groove 215, the groove wall of the second spring groove 231 and the space enclosed by the outer side of the stabilizing valve 4 form a liquid inlet pressure chamber 6.

When the pilot-operated pressure reducing valve is started, the liquid passing groove 221 is not communicated with the liquid inlet hole 211 and the pressure relief hole 213, and at the moment, high-pressure liquid flows into the second communication hole 223 from the liquid inlet cavity 11 through the liquid inlet hole 211 and then continues to flow through the connection hole 224 and flows into the liquid inlet pressure cavity 6 through the interior of the stabilizing valve 4; the low-pressure liquid in the liquid outlet cavity 12 flows into the liquid passing groove 221 from the liquid outlet hole 212, further flows into the first communication hole 222, and finally flows into the liquid outlet pressure cavity 7. The low-pressure liquid in the liquid outlet pressure cavity 7 generates a first thrust to the main piston 22, the first thrust moves close to the valve core cover 23, the high-pressure liquid in the liquid inlet pressure cavity 6 generates a second thrust to the stabilizing valve 4, the second thrust moves close to the bottom of the valve core hole 13, the stabilizing valve 4 drives the second spring sleeve 26 and the main piston 22 to move towards the direction far away from the valve core cover 23, the liquid passing groove 221 is further communicated with the liquid inlet hole 211 and the liquid outlet hole 212, and the second spring sleeve 26 extrudes the first elastic piece 24 to enable the first elastic piece 24 to generate an elastic force to the second spring sleeve 26, and the elastic force moves towards the direction far away from the bottom of the valve core hole 13. When the pressure in the liquid outlet cavity 12 gradually increases, the first thrust is gradually increased until the first thrust is smaller than the second thrust, the elastic force generated by the first elastic member 24 pushes the stabilizer valve 4 to drive the main piston 22 to move in the direction away from the bottom of the valve core hole 13 until the liquid inlet hole 211 is disconnected from the liquid outlet hole 212, and then the pressure in the liquid outlet cavity 12 maintains the required pressure.

The outer wall of the valve core cylinder 21 is provided with a pilot hole 216 communicating the outside of the valve core cylinder 21 with the liquid inlet pressure cavity 6, and the outer valve body 1 is provided with a first pilot connecting hole 15 communicating the inside of the pilot valve 3 with the pilot hole 216; the outer valve body 1 is provided with a first pilot pressure relief hole 16, and the first pilot pressure relief hole 16 communicates the inside of the pressure relief groove 214 with the inside of the pilot valve 3.

The pilot valve 3 can be through the pressure of liquid in the first guide connecting hole 15 control feed liquor pressure chamber 6, and then can control the second thrust, because the second thrust can be controlled, and then can control feed liquor hole 211 and play liquid hole 212's intercommunication, make the pressure that goes out liquid chamber 12 can be by effectual control or regulation, such setting up makes people can adjust and stabilize the oil pressure that the pilot-operated relief pressure valve goes out liquid department, and then satisfy the demand of whole oil circuit to the pilot-operated relief pressure valve goes out liquid department oil pressure.

Referring to fig. 1 and 2, the stabilizing valve 4 includes a stabilizing valve body 41 and a stabilizing valve core 42, the stabilizing valve body 41 is disposed at one end of the main piston 22 close to the valve core cover 23, the stabilizing valve body 41 has a two-section coaxial stepped shaft structure, a shaft end with a small diameter of the stabilizing valve body 41 is in threaded connection with the connecting hole 224, a third spring groove 413 is formed on a peripheral surface of a shaft end with a large diameter of the stabilizing valve body 41, and a groove wall of the third spring groove 413 abuts against the second spring sleeve 26. The end face of the large-diameter section of the stabilizing valve body 41 is provided with a stabilizing groove 411, the stabilizing groove 411 is cylindrical, the stabilizing valve core 42 is matched with the groove wall shaft hole of the stabilizing groove 411, a stabilizing plug 44 for plugging the stabilizing groove 411 is fixedly connected in the stabilizing groove 411, the bottom of the stabilizing groove 411 is far away from the stabilizing plug 44, and the stabilizing valve core 42 is close to the bottom of the stabilizing groove 411. The end face of the stabilizing valve core 42 close to the stabilizing plug 44 is provided with a fourth spring groove 421, the end face of the stabilizing plug 44 close to the stabilizing valve core 42 is abutted with a second elastic piece 43 capable of pushing the stabilizing valve core 42 to move towards the direction far away from the stabilizing plug 44, and one end of the second elastic piece 43 far away from the stabilizing plug 44 is abutted with the bottom of the fourth spring groove 421. The bottom of the fourth spring groove 421 is provided with a damping hole 422 which penetrates through the stable valve core 42 and has a damping effect on hydraulic oil, the bottom of the third spring groove 413 is provided with a pilot liquid passing hole 414 which penetrates through the stable valve body 41, the pilot liquid passing hole 414 is positioned between the stable valve core 42 and the stable plug 44, and the bottom of the stable groove 411 is provided with a pilot liquid inlet hole 412 which circumferentially penetrates through the stable valve body 41.

When the pilot type pressure reducing valve works normally, the pressure of the liquid outlet cavity 12 is stably maintained at the required pressure, when people adjust the pressure of the liquid inlet pressure cavity 6 through the pilot valve 3, high-pressure liquid of the liquid inlet cavity 11 flows into the connecting hole 224 and flows to the end face, far away from the stabilizing plug 44, of the stabilizing valve core 42 along the pilot liquid inlet hole 412, because the damping hole 422 has an effect of hindering the flow of the liquid, the high-pressure liquid and the liquid inside the fourth spring groove 421 form a pressure difference, the high-pressure liquid pushes the stabilizing valve core 42 to move towards the direction close to the stabilizing plug 44, the second elastic piece 43 is further extruded, the stabilizing valve core 42 blocks the pilot liquid passing hole 414, and therefore the pressure of the liquid inlet pressure cavity 6 is stabilized. Meanwhile, high-pressure liquid flows into the fourth spring groove 421 through the damping hole 422, pressure is gradually balanced, the stabilizing valve core 42 is no longer used for plugging the pilot liquid passing hole 414, the pressure of the liquid inlet pressure cavity 6 is steadily increased, and the pressure of the liquid outlet cavity 12 is steadily increased until the required pressure is reached. The design of the stabilizing valve 4 ensures that when people control the pressure of the liquid outlet cavity 12 through the pilot valve 3, the pressure of the liquid outlet cavity 12 cannot suddenly change, so that the pressure in the hydraulic oil circuit behind the liquid outlet of the pilot type reducing valve cannot suddenly change, and the hydraulic oil circuit is protected.

The pilot valve 3 includes a pilot valve body 31, the pilot valve body 31 is an aluminum mechanism, the pilot valve body 31 is fixedly connected to the side surface of the outer valve body 1, a cylindrical first guide groove 311 is formed in the pilot valve body 31, one end of the first guide groove 311 is communicated with the external environment, a pilot fixed valve core 32 is fixedly connected in the pilot groove 311, a pilot movable valve core 33 is matched with an inner shaft hole of the pilot groove 311, the pilot movable valve core 33 is arranged between the pilot fixed valve core 32 and the bottom of the pilot groove 311, and a flat pressure groove 331 which facilitates liquid to flow from one end surface of the pilot movable valve core 33 to the other end surface is formed in the peripheral surface of the pilot movable valve core 33. A pilot control hole 321 penetrating through the pilot fixed valve core 32 is coaxially formed in the end face of the pilot fixed valve core 32, the end of the pilot fixed valve core 33 close to the pilot fixed valve core 32 is a conical plug 34, and one end of the conical plug 34 close to the pilot fixed valve core 32 can extend into the pilot control hole 321 and plug the pilot control hole 321. The pilot valve body 31 is provided with an external plug 35 capable of plugging the notch of the pilot groove 311, a space enclosed by the external plug 35, the groove wall of the pilot groove 311 and the pilot fixed valve core 32 is a pilot liquid inlet area 36, a space enclosed by the groove wall of the pilot fixed valve core 32, the pilot movable valve core 33 and the pilot guide groove 311 is a pilot liquid outlet area 37, a second pilot connecting hole 312 for communicating the first pilot connecting hole 15 with the pilot liquid inlet area 36 is formed in the pilot valve body 31, and a second pilot pressure relief hole 313 for communicating the first pilot pressure relief hole 16 with the pilot liquid outlet area 37 is formed in the pilot valve body 31. One end of the pilot valve body 31, which is far away from the external plug 35, is connected with an electromagnetic coil 38 through a thread, wherein the electromagnetic coil can control the thrust of the pilot valve spool 33 to push the conical plug 34.

When the pilot type pressure reducing valve is started, high-pressure liquid flows into the liquid inlet cavity 11, the high-pressure liquid further flows into the liquid inlet pressure cavity 6, flows through the pilot hole 216 through the first pilot connecting hole 15 and the second pilot connecting hole 312, the high-pressure liquid flows into the pilot liquid inlet area 36, the high-pressure liquid continues to flow into the pilot control hole 321, a third thrust force which enables the conical plug 34 to move towards the direction away from the pilot fixed valve core 32 is generated on the conical plug 34, the electromagnetic coil 38 works to enable the pilot movable valve core 33 to push the conical plug 34 to generate a fourth thrust force which moves towards the direction close to the external plug 35, after the third thrust force is gradually increased until the third thrust force is slightly larger than the fourth thrust force, the conical plug 34 moves the pilot liquid outlet area 37 towards the direction away from the pilot fixed valve core 32 to be communicated with the pilot liquid inlet area 36, the pilot liquid outlet area 37 is communicated with the oil tank through the first pilot pressure relief hole 16 and the second pilot pressure relief hole 313, and the pressure of the pilot liquid inlet area 36 is reduced until the generated third thrust force is equal to the fourth thrust force, thus, the pressure of the pilot liquid inlet area 36 and the pressure of the liquid inlet pressure cavity 6 communicated with the pilot liquid inlet area 36 are always kept at the set pressure, and the pressure of the liquid outlet cavity 12 is kept at the set pressure.

Compare and make in pilot valve body 31 with plastics, the pilot valve body 31 that aluminium system material made has higher structural strength, makes the whole more not fragile of pilot valve 3, and then prolongs the life of pilot-operated formula relief pressure valve. Compared with the situation that the fourth thrust generated by the pilot operated valve core 33 is generated by the elastic part, the fourth thrust can be adjusted due to the design of the electromagnetic coil 38, and meanwhile, due to the detachable design of the electromagnetic coil 38, people can conveniently replace the electromagnetic coil 38 in time when the electromagnetic coil 38 is damaged, so that the service life of the pilot operated pressure reducing valve is further prolonged; and people can change the model of the electromagnetic coil 38 according to the requirements of different oil paths on the pilot-operated reducing valve, so that fourth thrust in different ranges is generated, and the requirements of the oil paths are met. The flat pressure groove 331 is provided to balance the liquid pressures on both end surfaces of the pilot spool 33, and to smoothly move the pilot spool 33 inside the pilot groove 311.

The inside one-way hole 14 that communicates feed liquor chamber 11 and play liquid chamber 12 of seting up of outer valve body 1, threaded connection has one end and one-way hole 14 to be close to the check valve 5 of 12 one end butts in play liquid chamber on the outer valve body 1, and check valve 5 can make in the one-way hole 14 liquid only from being close to 12 one end flow directions in play liquid chamber and being close to 11 one ends in feed liquor chamber.

When the pilot type pressure reducing valve is connected to a hydraulic oil circuit, after the hydraulic oil circuit stops working, the pressure of the liquid inlet of the pilot type pressure reducing valve is almost zero, the pressure of the liquid outlet is still the pressure during working, the pressure of the liquid outlet cavity 12 is larger than the pressure of the liquid inlet cavity 11, the check valve 5 is conducted, the pressure of the liquid cavity 12 is released, and then the pressure of the hydraulic oil circuit connected with the liquid outlet of the pilot type pressure reducing valve is released. The design of the one-way valve 5 enables the hydraulic oil circuit to automatically release pressure, so that all components of the oil circuit are in a light load state, and the hydraulic oil circuit is protected.

In the embodiment, the first elastic member 24 and the second elastic member 43 are both springs, and other first elastic members 24 and second elastic members 43 with the same effect are still suitable.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims

1. The pilot-operated proportional pressure reducing valve is characterized in that: the oil-gas pressure relief valve comprises an outer valve body (1), wherein a liquid inlet cavity (11), a liquid outlet cavity (12) and a pressure relief long hole (17) communicated with an oil tank are formed in the outer valve body (1), a valve core cover (23) is arranged on the outer valve body (1), a main piston (22) capable of communicating the liquid inlet cavity (11) with the liquid outlet cavity (12) or communicating the liquid outlet cavity (12) with the pressure relief long hole (17) is arranged in the outer valve body (1), a liquid outlet pressure cavity (7) is formed between the end face, close to the liquid inlet cavity (11), of the main piston (22) and the outer valve body (1), and a liquid inlet pressure cavity (6) is formed between the end face, far away from the liquid outlet pressure cavity (7), of the main piston (22) and the valve core cover (23);

a first communicating hole (222) communicating the liquid outlet cavity (12) and the liquid outlet pressure cavity (7) is formed in the main piston (22), a second communicating hole (223) communicating the liquid inlet cavity (11) and the liquid inlet pressure cavity (6) is formed in the main piston (22), and a stabilizing valve (4) for stabilizing the liquid pressure flowing into the liquid inlet pressure cavity (6) is connected to the end face, far away from the liquid outlet pressure cavity (7), of the main piston (22);

the outer valve body (1) is provided with a pilot valve (3) for controlling the liquid pressure in the liquid inlet pressure cavity (6).

2. The pilot-operated proportional pressure reducing valve according to claim 1, wherein: the pilot valve (3) comprises a pilot valve body (31), the pilot valve body (31) is arranged on the outer valve body (1), a pilot fixed valve spool (32) with two through end faces is connected inside the pilot valve body (31), a pilot movable valve spool (33) capable of plugging the pilot fixed valve spool (32) is matched with a shaft hole inside the pilot valve body (31), a space formed by the end face, far away from the pilot movable valve spool (33), of the pilot fixed valve spool (32) and the pilot valve body (31) is communicated with the liquid inlet pressure cavity (6), a region formed by the surrounding of the pilot movable valve spool (33), the pilot fixed valve spool (32) and the pilot valve body (31) is communicated with the oil tank, and an electromagnetic coil (38) capable of controlling the force enabling the pilot movable valve spool (33) to abut against the pilot fixed valve spool (32) is arranged on the pilot valve body (31).

3. The pilot-operated proportional pressure reducing valve according to claim 2, wherein: the electromagnetic coil (38) is detachably connected to the pilot valve body (31).

4. The pilot-operated proportional pressure reducing valve according to claim 2, wherein: the pilot valve body (31) is made of an aluminum material.

5. The pilot-operated proportional pressure reducing valve according to claim 2, wherein: the peripheral surface of the pilot valve core (33) is provided with a flat pressing groove (331) which is communicated with two end surfaces of the pilot valve core (33).

6. The pilot-operated proportional pressure reducing valve according to claim 2, wherein: the peripheral surface of the main piston (22) is provided with a valve core cylinder (21), the valve core cylinder (21) is matched with the shaft hole of the outer valve body (1), the valve core cylinder (21) is provided with a liquid inlet hole (211) communicated with the inside of the valve core cylinder (21) and the liquid inlet cavity (11), a liquid outlet hole (212) communicated with the inside of the valve core cylinder (21) and the liquid outlet cavity (12) and a pressure relief hole (213) communicated with the inside of the valve core cylinder (21) and the pressure relief long hole (17), the end surface of the valve core cylinder (21) far away from the liquid inlet hole (211) is abutted to a valve core cover (23), and the valve core cover (23) is in threaded connection with the outer valve body (1).

7. The pilot-operated proportional pressure reducing valve according to claim 2, wherein: the pilot valve body (31) is provided with an external plug (35) which can communicate the inside with the outside of the pilot valve body (31).

8. The pilot-operated proportional pressure reducing valve according to claim 1, wherein: the inner part of the outer valve body (1) is provided with a one-way hole (14) for communicating the liquid inlet cavity (11) with the liquid outlet cavity (12), and the outer valve body (1) is in threaded connection with a one-way valve (5) which enables liquid in the one-way hole (14) to flow to the end close to the liquid inlet cavity (11) only from the end close to the liquid outlet cavity (12).