CN207437914U - Pilot-operated type static-difference-free water pressure overflow valve - Google Patents

Pilot-operated type static-difference-free water pressure overflow valve Download PDF

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Publication number
CN207437914U
CN207437914U CN201721413538.0U CN201721413538U CN207437914U CN 207437914 U CN207437914 U CN 207437914U CN 201721413538 U CN201721413538 U CN 201721413538U CN 207437914 U CN207437914 U CN 207437914U
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China
Prior art keywords
valve
pilot
main valve
main
guide
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Expired - Fee Related
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CN201721413538.0U
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Chinese (zh)
Inventor
张利
朱耿寅
马长征
张娟
王首军
夏自祥
李小冬
崔祥府
祝雁辉
王凤霞
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Jining University
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Jining University
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Abstract

The utility model relates to a pilot-operated no-static-difference water pressure overflow valve, belonging to the field of fluid transmission and control, comprising a pilot valve, a main valve and a valve channel closed loop feedback control system; the pilot valve comprises a pilot valve sleeve, a pilot valve core, a pilot valve body, a buffer spring and an end cover, wherein the main valve comprises a main valve body, a main valve core, a main valve sleeve, a main valve seat and a main valve reset spring, the closed-loop feedback control system of the valve channel comprises a miniature pressure sensor, a driver and a pore channel for communicating the pilot valve with the main valve, a pull rod of the driver is connected with one end of the pilot valve core, the pilot valve core is a single-side zero-opening two-way sliding valve, and three uniform pressure grooves are uniformly formed in the cylindrical surfaces of convex shoulders. The utility model discloses a pressure sensor direct detection main valve inlet pressure's change directly transmits the signal that detects for opening that the pilot valve was controlled to the driver, constitutes closed loop pressure feedback control and makes control accuracy high, corresponding fast, stability good, realizes not having the quiet difference control.

Description

Pilot-operated type floating water hydraulic relief valve
Technical field
The utility model belongs to Fluid Transmission and Control field, and in particular to a kind of pilot-operated type floating water hydraulic relief valve.
Background technology
Water hydraulic system with its pollution-free, good flame resistance, good economy performance, derive from a wealth of sources the advantages that become Fluid Transmission and Control One of important research direction.Wherein, hydraulic pressure pressure-control valve is one of critical elements of hydraulic transmission system.But traditional pressure Force control valve is all to have difference limen, setting-pressure accuracy is relatively low and water hydraulic system exist big leakage, poor lubricity, it is perishable the defects of, and When the nominal pressure of pilot valve is higher, static difference can also increase.The measure for the reduction static difference that people generally use is will to adjust at present Pressure scope is divided into four grades (0.6~0.8MPa, 4~16MPa, 8~20MPa, 16~32MPa), pressing force requirement design four Root free height, internal diameter be identical and rigidity and the different pressure spring of steel wire diameter are applied to the pressure regulation of four level ranges. Suitable spring is selected according to the difference of operating pressure, to ensure that static difference is small as far as possible.But inherently analyze, it is additional Spring force and the hydraulic power of stable state still remain, therefore static difference also exists always.
Utility model content
The purpose of this utility model is to provide a kind of pilot-operated type floating water hydraulic relief valve, solves existing apparatus because adding bullet Spring force, steady-state fluid force cause static difference still eventually there are the problem of.
The utility model pilot-operated type floating water hydraulic relief valve is controlled including pilot valve, main valve and the internal feedback of valve road closed loop System;The pilot valve includes guide's valve pocket, pilot valve, guide valve blocks, buffer spring and end cap, and guide's valve pocket is mounted on first In the hole of pilot valve body, pilot valve is mounted in guide's valve pocket, and buffer spring is between pilot valve and end cap, the main valve bag Containing main valve body, main valve plug, main valve housing, main valve seat and main valve resetting spring, main valve housing, main valve seat are mounted on the in vivo hole of main valve In, main valve seat is in the lower section of main valve housing, and is provided with sealing ring two between main valve housing, main valve seat and the in vivo hole of main valve, main Spool is mounted in main valve housing, and main valve resetting spring is mounted in the spring cavity of main valve plug afterbody;The valve road closed loop internal feedback Control system includes micro pressure sensor, driver and the duct of connection pilot valve and main valve, and main valve is connected with pilot valve Sealing ring four is provided at duct, micro pressure sensor is arranged at oil inlet, the pull rod connection pilot valve one of driver End, pilot valve are unilateral zero lap two-way guiding valve, and valve core of the spool valve is relatively more steady during opening and closing, and valve core of the spool valve can Effectively to inhibit self-excited vibration, noise can be effectively reduced, pilot valve is gap-matched with guide's valve pocket, and zero lap is slided Valve has linear flow gain, and performance is best, and unilateral guiding valve is simple to manufacture, uniform each on the convex shoulder cylindrical surface of pilot valve both ends Open three balancing slits;Sealing ring one is provided on the inside of driver.Driver is ultra-magnetic telescopic accurate displacement driver, is driven From band signal receiving device inside device.
The main valve plug is not likely to produce vibration, the operation is stable, main valve core head uses parabola using three section concentric structures Structure makes the water pressure impact force that main valve core head is subject to balanced and extends back, reduces the destruction of cavitation erosion, main valve plug and main valve seat Two-stage throttle orifice is formed, reduces the operting differential pressure of each valve port, improves the anti-cavitation ability of throttle valve, restriction uses Long straight-through channel type.Cavitation erosion, wire drawing, noise and the oscillation phenomenon of valve are effectively reduced, ensure that control accuracy and the use of valve Service life.
The pilot valve end face of the end cap one side is provided with arc-shaped slot, increases pilot valve kinetic damping, improves first The stability of pilot valve, end cap inside are fixed with cushion pad, make spool movement more steady.
The oil inlet is connected with guide duct with guide's valve pocket left end, and fixed damper is provided in guide duct, main Valve body epicoele is provided with the oil duct in the middle part of connection guide's valve pocket, and dynamic damper, and oil duct and guide duct are provided in oil duct Connection.
Water outlet is provided in the middle part of the main valve body, water outlet uses the right-angle structure that circular arc seamlessly transits.Reduce because Vortex, noise and cavitation erosion caused by back cavity area of passage is uneven.
Safety valve is provided on the pilot valve, safety valve includes valve body of safety valve, safety valve resetting spring and safety valve Spool, safe valve core is mounted in the hole of valve body of safety valve, and one end is connected with safety valve resetting spring, and safety valve resets bullet The spring other end is mounted in spring cavity, and the hole of the safe valve core other end and valve body of safety valve forms cone sealing, and safety valve valve Other end connection guide duct in the hole of body, the hole middle part upper end connection guide valve pocket middle part of valve body of safety valve, lower end connects out The mouth of a river.Safety valve forms a traditional pilot operated compound relief valve with main valve, when system pressure mutation or electronic circuit failure, energy It is enough to open immediately, make system decompression and keep system pressure constant.Guide is provided with plug screw at duct.
Guide valve blocks are made of stainless steel, and spool and valve pocket are made of engineering ceramic material, can effectively be resisted The cavitation erosion and wire drawing of water destroy, and pilot valve, the controllable very little of the fit clearance of guide's valve pocket.Main valve body, main valve seat are adopted It is made of stainless steel material, main valve plug is made of engineering plastic materials, and main valve plug and main valve seat are matched using soft or hard material, i.e., It can ensure sealing performance when valve port is closed, and the shock and vibration generated when closing can be reduced, prolong the service life.
Compared with prior art, the utility model has the advantage of:
1st, the variation of main valve inlet pressure is directly detected using pressure sensor, the signal of detection is directly passed to driving Device controls the unlatching of pilot valve, forms closed loop pressure feedback control, control accuracy height, fast response time, stability are good, realization Zero steady state error control.
2nd, pilot valve uses unilateral zero lap two-way guiding valve, more stablizes, uniform on the convex shoulder cylindrical surface of spool both ends Three balancing slits are respectively opened, reduce hydraulic card clamping force, spool is avoided to generate clamping phenomenon with valve pocket.
3rd, main valve plug uses parabolic structure using three section concentric structures, main valve core head, and main valve plug is formed with main valve seat Two-stage throttle orifice, restriction is using long straight-through channel type;Cavitation erosion, wire drawing, noise and the oscillation phenomenon of valve are effectively reduced, is protected The control accuracy and service life of valve are demonstrate,proved;Water outlet uses the right-angle structure that circular arc seamlessly transits, and reduces because of back cavity mistake Vortex, noise and cavitation erosion caused by flow area is uneven.
Description of the drawings
Fig. 1 is the structure diagram of the utility model;
Fig. 2 is the enlarged structure schematic diagram at A in Fig. 1;
In figure:1st, cushion pad, 2, buffer spring, 3, guide's valve pocket, 4, pilot valve, 5, guide valve blocks, 6, pull rod, 7, close Seal one, 8, driver, 9, valve body of safety valve, 10, safety valve resetting spring, 11, safe valve core, 12, main valve body, 13, main Spool, 14, main valve housing, 15, main valve seat, 16, micro pressure sensor, 17, guide duct, 18, main valve resetting spring, 19, solid Determine damper, 20, dynamic damper, 21, end cap, 22, balancing slit, 23, arc-shaped slot.
Specific embodiment
Below against attached drawing, specific embodiment of the present utility model is described in further detail.
Pilot-operated type floating water hydraulic relief valve as depicted in figs. 1 and 2, including anti-in pilot valve, main valve and valve road closed loop Present control system;The pilot valve includes guide's valve pocket 3, pilot valve 4, guide valve blocks 5, buffer spring 2 and end cap 21, guide Valve pocket 3 be mounted on guide valve blocks 5 hole in, pilot valve 4 be mounted on guide's valve pocket 3 in, buffer spring 2 pilot valve 4 with Between end cap 21, the main valve includes main valve body 12, main valve plug 13, main valve housing 14, main valve seat 15 and main valve resetting spring 18, main Valve pocket 14, main valve seat 15 are mounted in the hole in main valve body 12, and main valve plug 13 is mounted in main valve housing 14, main valve resetting spring 18 In the spring cavity of 13 afterbody of main valve plug;The valve road closed loop internal feedback control system include micro pressure sensor 16, Driver 8 and the duct of connection pilot valve and main valve, micro pressure sensor 16 are arranged at oil inlet, the pull rod 6 of driver 8 Connect pilot valve 4 one end, pilot valve 4 is unilateral zero lap two-way guiding valve, on 4 both ends convex shoulder cylindrical surface of pilot valve uniformly Respectively open three balancing slits 22.The inside of driver 8 is provided with sealing ring 1.
For the main valve plug 13 using three section concentric structures, 13 head of main valve plug uses parabolic structure, main valve plug 13 and master Valve seat 15 forms two-stage throttle orifice, and restriction is using long straight-through channel type.
4 end face of pilot valve of 21 one side of end cap is provided with arc-shaped slot 23, and 21 inside of end cap is fixed with cushion pad 1.
The oil inlet is connected with guide duct 17 with 3 left end of guide's valve pocket, and fixed damping is provided in guide duct 17 Device 19,12 epicoele of main valve body are provided with the oil duct at 3 middle part of connection guide valve pocket, and dynamic damper 20, and oil are provided in oil duct Road is connected with guide duct 17.The epicoele of main valve is provided with the duct of connection pilot valve right chamber.
12 middle part of main valve body is provided with water outlet, and water outlet uses the right-angle structure that circular arc seamlessly transits.
Safety valve is provided on the pilot valve, safety valve includes valve body of safety valve 9, safety valve resetting spring 10 and safety Valve core 11, safe valve core 11 is mounted in the hole of valve body of safety valve 9, and one end is connected with safety valve resetting spring 10, peace 10 other end of full valve resetting spring is mounted in spring cavity, and the hole of safe 11 other end of valve core and valve body of safety valve 9, which is formed, bores Sealing, and other end connection guide duct 17 in the hole of valve body of safety valve 9, the hole middle part upper end connection guide of valve body of safety valve 9 3 middle part of valve pocket, lower end connection water outlet.
Operation principle:Plug screw in guide duct 17 is taken down, liquid stream enters overflow valve from oil inlet P mouth and is divided into two-way, all the way It directly acts on main valve plug 13, another way then by guide duct 17 and fixed damper 19 to enter in pilot valve, into guide It is divided into after valve as two-way, all the way into the left chamber of pilot valve, all the way then into the intermediate cavity of pilot valve and through dynamic damper 20 enter the epicoele of main valve, then enter back into the right chamber of pilot valve, and safety valve is constantly in closure since the pressure of setting is larger State.As long as pilot valve is not turned on, the pressure of two chambers is just certain equal above and below main valve, and main valve is closed.
When micro pressure sensor 16, which detects inlet pressure P, is more than setting value, driver 8, which generates pulling force, makes pilot valve 4 move right, and control side and the guide's valve pocket 3 of pilot valve 4 form a small opening, the liquid stream warp of pilot valve intermediate cavity It crosses opening and flows to main valve water outlet T, liquid stream is by fixed damper 19 and generates pressure drop, and cavity pressure under main valve is made to be higher than epicoele pressure Power, main valve plug 13 move up, and main valve opens overflow, and is maintained at an equilbrium position, valve port pressure P and the driver 8 of main valve The linear variation of voltage signal, when running into external disturbance, micro pressure sensor 16 experiences this variation, and by signal transmission To driver 8, pressure into Mobile state is adjusted by changing voltage signal, closed loop feedback system is formed, when pilot valve 4 returns to During initial position, 13 stop motion of main valve plug, at this moment inlet pressure be substantially equal to set-point.
When external disturbing force acts on main valve plug 13 and makes its movement, the epicoele of main valve plug 13 will generate one and add Flow, this additional flow is by that will generate pressure drop during dynamic damper 20,4 or so two cavity pressure of pilot valve at this time Unequal, the stress balance of pilot valve is destroyed, and then generates additional dynamic adjustment power.For example, if main valve plug 13 is downward Movement, then pilot valve left chamber pressure is more than right chamber pressure, and at this moment additional dynamic, which adjusts power, makes pilot valve 4 move right, first Valve port opening increase is led, then makes left chamber rapid pressure drop, until pilot valve or so cavity pressure rebalances, is realized dynamic State feedback control, it is conducive to overflow valve and is rapidly reached stabilization, improves and improve the dynamic characteristic of overflow valve and jamproof Ability.
System pressure mutation is excessively high in order to prevent, and the utility model pilot-operated type floating water hydraulic relief valve, which is nested with, to be mounted with One safety valve, it forms a traditional pilot operated compound relief valve with main valve, (has larger pressure when system pressure mutation is very high Peak value) or electronic circuit fail when, safety valve is opened immediately, is made system decompression and is kept the constant of system pressure, safety valve As long as the maximum pressure being likely to occur in setting pressure slightly above system or circuit.
In conclusion the utility model directly detects the variation of main valve inlet pressure using pressure sensor, detection Signal is directly passed to driver to control the unlatching of pilot valve, forms closed loop pressure feedback control, and control accuracy is high, response speed Degree is fast, stability is good, realizes zero steady state error control;Pilot valve uses unilateral zero lap two-way guiding valve, more stablizes, spool both ends It is uniform on convex shoulder cylindrical surface respectively to open three balancing slits, reduce hydraulic card clamping force, spool is avoided to generate clamping phenomenon with valve pocket;It is main Spool uses parabolic structure using three section concentric structures, main valve core head, and main valve plug forms two-stage throttle orifice with main valve seat, Restriction is using long straight-through channel type;Cavitation erosion, wire drawing, noise and the oscillation phenomenon of valve are effectively reduced, ensure that the control of valve Precision and service life;Water outlet uses the right-angle structure that circular arc seamlessly transits, and reduces because back cavity area of passage is uneven Caused by vortex, noise and cavitation erosion.

Claims (6)

1. a kind of pilot-operated type floating water hydraulic relief valve, including pilot valve, main valve and valve road closed loop internal feedback control system;It is described Pilot valve includes guide's valve pocket (3), pilot valve (4), guide valve blocks (5), buffer spring (2) and end cap (21), guide's valve pocket (3) in the hole of guide valve blocks (5), pilot valve (4) is mounted in guide's valve pocket (3), and buffer spring (2) is in pilot valve Between core (4) and end cap (21), the main valve include main valve body (12), main valve plug (13), main valve housing (14), main valve seat (15) and Main valve resetting spring (18), main valve housing (14), main valve seat (15) are mounted in the hole in main valve body (12), main valve plug (13) installation In main valve housing (14), main valve resetting spring (18) is mounted in the spring cavity of main valve plug (13) afterbody;It is characterized in that:It is described Valve road closed loop internal feedback control system includes micro pressure sensor (16), driver (8) and the hole of connection pilot valve and main valve Road, micro pressure sensor (16) are arranged at oil inlet, pull rod (6) connection pilot valve (4) one end of driver (8), first Guide valve core (4) is unilateral zero lap two-way guiding valve, and uniformly three balancing slits are respectively opened on pilot valve (4) both ends convex shoulder cylindrical surface (22)。
2. pilot-operated type floating water hydraulic relief valve according to claim 1, it is characterised in that:The main valve plug (13) uses Three section concentric structures, main valve plug (13) head use parabolic structure, and main valve plug (13) forms two-stage throttling with main valve seat (15) Valve port, restriction is using long straight-through channel type.
3. pilot-operated type floating water hydraulic relief valve according to claim 1, it is characterised in that:End cap (21) one side Pilot valve (4) end face is provided with arc-shaped slot (23), and cushion pad (1) is fixed on the inside of end cap (21).
4. pilot-operated type floating water hydraulic relief valve according to claim 1, it is characterised in that:The oil inlet and pilot valve Set (3) left end is connected with guide duct (17), and fixed damper (19), main valve body (12) epicoele are provided in guide duct (17) The oil duct connected in the middle part of guide's valve pocket (3) is provided with, dynamic damper (20), and oil duct and guide duct are provided in oil duct (17) connect.
5. pilot-operated type floating water hydraulic relief valve according to claim 4, it is characterised in that:In the middle part of the main valve body (12) Water outlet is provided with, water outlet uses the right-angle structure that circular arc seamlessly transits.
6. pilot-operated type floating water hydraulic relief valve according to claim 5, it is characterised in that:It is provided on the pilot valve Safety valve, safety valve include valve body of safety valve (9), safety valve resetting spring (10) and safe valve core (11), safe valve core (11) in the hole of valve body of safety valve (9), and one end is connected with safety valve resetting spring (10), safety valve resetting spring (10) other end is mounted in spring cavity, and the hole of safe valve core (11) other end and valve body of safety valve (9) forms cone sealing, and Other end connection guide duct (17) in the hole of valve body of safety valve (9), the hole middle part upper end connection pilot valve of valve body of safety valve (9) It covers in the middle part of (3), lower end connection water outlet.
CN201721413538.0U 2017-10-28 2017-10-28 Pilot-operated type static-difference-free water pressure overflow valve Expired - Fee Related CN207437914U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201721413538.0U CN207437914U (en) 2017-10-28 2017-10-28 Pilot-operated type static-difference-free water pressure overflow valve

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201721413538.0U CN207437914U (en) 2017-10-28 2017-10-28 Pilot-operated type static-difference-free water pressure overflow valve

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109630493A (en) * 2019-01-24 2019-04-16 安徽理工大学 A kind of hydraulic pressure combination valve based on micro forming spool and special-shaped valve chamber
CN109854563A (en) * 2019-03-05 2019-06-07 安徽理工大学 A kind of pressure regulation pressure limiting combination overflow valve
CN112460321A (en) * 2021-01-11 2021-03-09 福鼎市鑫龙机械部件有限公司 Piston type electromagnetic pulse valve controlled by slide valve, control valve body and working method of piston type electromagnetic pulse valve
CN112747001A (en) * 2021-01-25 2021-05-04 湖南人文科技学院 Pilot-operated overflow valve with position feedback
CN113251021A (en) * 2021-06-01 2021-08-13 安徽理工大学 Two-position reversing valve with pilot function
CN113606369A (en) * 2021-07-21 2021-11-05 哈电集团哈尔滨电站阀门有限公司 Pilot-operated safety valve with novel structure and use method
CN113738923A (en) * 2021-08-25 2021-12-03 浙江大学 Pilot-operated high-pressure reducing valve with stable output flow and pressure and method thereof

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109630493A (en) * 2019-01-24 2019-04-16 安徽理工大学 A kind of hydraulic pressure combination valve based on micro forming spool and special-shaped valve chamber
CN109854563A (en) * 2019-03-05 2019-06-07 安徽理工大学 A kind of pressure regulation pressure limiting combination overflow valve
CN112460321A (en) * 2021-01-11 2021-03-09 福鼎市鑫龙机械部件有限公司 Piston type electromagnetic pulse valve controlled by slide valve, control valve body and working method of piston type electromagnetic pulse valve
CN112460321B (en) * 2021-01-11 2022-08-12 福鼎市鑫龙机械部件有限公司 Piston type electromagnetic pulse valve controlled by slide valve, control valve body and working method of piston type electromagnetic pulse valve
CN112747001A (en) * 2021-01-25 2021-05-04 湖南人文科技学院 Pilot-operated overflow valve with position feedback
CN113251021A (en) * 2021-06-01 2021-08-13 安徽理工大学 Two-position reversing valve with pilot function
CN113606369A (en) * 2021-07-21 2021-11-05 哈电集团哈尔滨电站阀门有限公司 Pilot-operated safety valve with novel structure and use method
CN113738923A (en) * 2021-08-25 2021-12-03 浙江大学 Pilot-operated high-pressure reducing valve with stable output flow and pressure and method thereof

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CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20180601

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