CN1945028A - Hydraulic balance valve capable of automatically adapting load change - Google Patents
Hydraulic balance valve capable of automatically adapting load change Download PDFInfo
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- CN1945028A CN1945028A CN 200610102007 CN200610102007A CN1945028A CN 1945028 A CN1945028 A CN 1945028A CN 200610102007 CN200610102007 CN 200610102007 CN 200610102007 A CN200610102007 A CN 200610102007A CN 1945028 A CN1945028 A CN 1945028A
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Abstract
The present invention is a kind of hydraulic balance valve capable of adapting load change automatically, belongs to the field of hydraulic control valve technology, and aims at solving the problem of matching the balance capacity and load. The hydraulic balance valve includes one main valve, one load adapting valve and one control valve. The main valve and the control valve are cone valves, and the load adapting valve is one slide valve. The load adapting valve has four external oil ports, one valve core with serial small holes, one strong spring and one weak spring, and can raise the regulating performance of the hydraulic balance valve. The present invention has the advantages of no low frequency jitter, capacity of regulating the throttle size automatically based on load to save energy, no leakage, and easy manufacture.
Description
Technical field
The present invention adapts to the hydraulically balanced valve of load variations automatically, belong to the hydraulic control valve class, relate to a kind of hydraulic control equilibrium valve of using in the control equilibrium valve, particularly crane telescopic cylinder of the vertical or various oil hydraulic cylinders that tilt to install of various open circuits of being used for.
Background technique
In the engineering machinery in modern times, construction machinery equipment, widely apply the hydraulic pressure load bearing system, wherein equilibrium valve is the crucial hydraulic package of this type systematic, the quality of its performance directly affects machine performance.Traditional hydraulically balanced valve is because its valve port is constant in the complete machine running, at the hydraulic pressure load bearing system during at bearing downlink, if load variations, the valve core opening of equilibrium valve is difficult to adapt to the variation of load, make hydraulic system in the decline process, produce low-frequency jitter, " nodding " phenomenon that promptly is commonly called as causes system extremely unstable, has a strong impact on the safety reliability of complete machine.During equilibrium valve work, mainly rely on and produce a counterpressure and load balance on the equilibrium valve.Traditional equilibrium valve mainly hinders balanced loaded weight by a fixing liquid, and when the resistance of this liquid is bigger, if load weight hour, system can cause the waste of energy; Less when the resistance of this liquid, if when load weight is big, system can produce phenomenons such as impact, vibration.This phenomenon is perplexing the designer and the hydraulic package manufacturing enterprise of the system that uses hydraulically balanced valve always.
Summary of the invention
The hydraulically balanced valve purpose that the present invention adapts to load variations automatically is, allow the balanced capacity of equilibrium valve change automatically with the variation of load, thereby problems such as the low-frequency jitter of resolution system in running, impact, vibration, provide simultaneously a kind of easy processing, highly sensitive, operate steadily, hydraulically balanced valve reliably.
The hydraulically balanced valve that the present invention adapts to load variations automatically is characterized in that mainly comprising main valve, adaptive load valve and control valve, each valve includes valve body, spool and two chambeies, front and back, main valve and control valve are cone valve structure, the adaptive load valve is a sliding valve structure, outer oil-collecting hole A, B, K, X are arranged on the valve body, oil pocket a, b are arranged in the main valve, and corresponding with the A mouth is a chamber; Main valve is made up of main valve plug 12, valve body 10, spring 11, nut 9, and spool tightly is attached to by spring on the inner conical surface of valve body, and control oil enters the right-hand member of piston 13 by the K mouth, opens main valve; The adaptive load valve is positioned at the main valve left end, form by valve pocket 15, spool 19, weak spring 16, spring seat 17, strong spring 18 and control piston 3, gapped cooperation between spool 19 and the valve pocket 15, in spool circumferential a series of aperture e is arranged, spool 19 tightly sticks together by weak spring 16, strong spring 18 and spring seat 17 with valve pocket 15, the adaptive load valve includes a strong spring 18 and a weak spring 16, two springs link together by spring seat 17, low pressure stage weak spring 16 works, high pressure section spring seat 17 automatic spacings, strong spring 18 works; Control valve is in parallel with main valve, is made up of control spool 8, spring 7, valve piece 6 and nut 5, links together by screw and main valve body.
The hydraulically balanced valve of described automatic adaptation load variations is characterized in that the spool 19 of described adaptive load valve is a cartridge type, and one end sealing has 3～5 roads sulculus that goes in ring near the outside of closed end; The other end opens wide, and there is a series of circumferential aperture e its outside, the valve pocket 15 supporting with it, and its internal diameter equates gapped cooperation with the external diameter nominal size of spool 19.
The hydraulically balanced valve of described automatic adaptation load variations is characterized in that described main valve is a Pilot operated check valve, adopts cone valve structure, and main valve plug is attached on the valve port of valve body 10 tightly by hollow nut 9 and spring 11.
The hydraulically balanced valve of described automatic adaptation load variations is characterized in that described control valve is an one-way valve, adopts cone valve structure.
The hydraulically balanced valve of described automatic adaptation load variations is characterized in that described adaptive load valve has one to be the drain tap X that makes things convenient for the design of adaptive load valve spring 16 and 18.
The hydraulically balanced valve of described automatic adaptation load variations is characterized in that the promising flow according to system of described adaptive load valve, makes the initial value of restriction e and the adjustable lever 1 of flow system flow coupling.
The hydraulically balanced valve of described automatic adaptation load variations is characterized in that the circumferential aperture e of described adaptive load valve, and the pressure reduction in orifice size vertically and d chamber and c chamber is hyperbolic relation.
The advantage that the present invention adapts to the hydraulically balanced valve of load variations automatically is: owing to adopted the adaptive load valve, equilibrium valve can adapt to the variation of load effectively, though be to the constant system of load, or the system of load variations, this valve can both well adapt to; Owing to adopted the adaptive load valve, can fundamentally solve the low-frequency jitter problem that the conventional balanced valve exists; Equally,, can automatically regulate the size of restriction, thereby can save energy, can rely on deadweight and load weight automatic steady ground descending fully according to load variations owing to adopted the adaptive load valve; Main valve and control valve adopt cone valve structure, when heavy burden is static, can prevent from effectively to leak, and prevent that weight from falling under the deadweight effect, guarantee safe operation; Because this valve all is made up of the most frequently used cone valve, guiding valve, so the easy processing of this valve; This valve is provided with adjustable lever, can regulate the area of initial restriction, makes this valve can adapt to different flow system flow scopes, and therefore, this valve has wider application area; When weight rose, because flow flows to the B mouth only by control valve from the A mouth, so the resistance of whole process liquid is little, energy loss was little, the efficient height.
Description of drawings
Fig. 1 adapts to the structural representation of the hydraulically balanced valve of load variations automatically, among the figure: 1 adjustable lever, 2 end caps, 3 control pistons, 4 control valve pieces, 5 screw plugs, 6 valve pieces, 7 springs, 8 control spools, 9 nuts, 10 valve bodies, 11 springs, 12 main valve plugs, 13 pistons, 14 valve plates, 15 valve pockets, 16 weak springs, 17 spring seats, 18 strong springs, 19 spools, A master's hydraulic fluid port one, B master's hydraulic fluid port two, X drain tap, K control port, a, b, c, d, f oil pocket, e throttling pore, g oilhole;
The structural representation of the spool of Fig. 2 adaptive load valve;
The unfolded drawing of the spool of Fig. 3 adaptive load valve;
Fig. 4 adapts to the schematic diagram of the hydraulically balanced valve of load variations automatically;
Fig. 5 present embodiment is applied in the schematic diagram on the hydraulic hoist.
Embodiment
Below in conjunction with accompanying drawing embodiment the hydraulically balanced valve that the present invention adapts to load variations is automatically described in further detail.
Referring to Fig. 1, the hydraulically balanced valve that adapts to load variations automatically comprises main valve, adaptive load valve, control valve, valve plate 14 and adjustable lever 1.Control valve is fixed by bolts to the top of main valve, and valve plate 14 is fixed by bolts to the right side of main valve, adjustable lever be positioned at main valve the left side and with adaptive load valve core 19 over against.Wherein control valve comprises control valve valve body 6, control valve spool 8, spring 7 and screw plug 5, and the main hydraulic fluid port A and the B of two chambeies and main valve connect before and after it, and its spool is a cone valve structure.
Main valve includes main valve body 10, main valve plug 12, spring 11, nut 9.Main valve plug is a cone valve structure.Nut 9 is a hollow structure, links up b chamber and c chamber.
The adaptive load valve is made up of valve pocket 15, spool 19, weak spring 16, spring seat 17, strong spring 18 and control piston 3.A series of circumferential aperture is arranged, referring to Fig. 2 and Fig. 3 on the spool 19.By spring 16, spring seat 17 and spring 18 valve pocket tightly is pressed on the valve body of main valve, the bottom of valve pocket has through hole, with hollow nut 9, c chamber and a chamber is linked up.The Regulation spring of adaptive load valve contains the Regulation spring 16 a little less than a strong Regulation spring 18 and, two springs link together by spring seat 17, the low pressure stage weak spring works, high pressure section spring seat automatic spacing, strong spring works, thereby can effectively reduce the size of valve, improve the adjusting function of valve.
Fig. 4 is the schematic diagram that adapts to the hydraulically balanced valve of load variations automatically.The symbolic reference here the symbol different with GB, but the symbol of the THE CONTROLLABLE of principle can be described more.
Fig. 5 is that present embodiment is applied in the hydraulic schematic diagram on the hydraulic hoist amplitude of oscillation oil cylinder.The main hydraulic fluid port B of this valve links to each other with the rodless cavity of hoist amplitude of oscillation cylinder; The A mouth links to each other with the B1 mouth of control valve with high-pressure oil pipe; Control port K links to each other with the rod chamber of hoist amplitude of oscillation cylinder respectively, the A1 mouth of control valve links to each other; The X mouth is a drain tap, directly takes back fuel tank.Other two hydraulic fluid port P, T of hoist control valve connect pressure oil-source and oil sump tank respectively.
The working procedure of this valve is as follows:
1. when hoist normally hoists, the 3-position 4-way control valve is changed to the position of right-hand member.At this moment, pressure oil communicates with hydraulic fluid port A by the hydraulic fluid port B1 of control valve; The rod chamber of hoist amplitude of oscillation cylinder communicates with fuel tank by the hydraulic fluid port A1 of control valve.Pressure oil enters from main hydraulic fluid port A, act on the cavity of resorption of main valve and control valve, overcome spring 7 and spring 11 is opened main valve and control valve, because the main valve epicoele has the adaptive load valve, therefore, pressure oil is mainly by opening control valve, enter the rodless cavity of amplitude of oscillation cylinder from A mouth, a chamber, d chamber, B mouth, promote the oil cylinder piston bar and stretch out, the fluid that the thick stick chamber is arranged of amplitude of oscillation cylinder is through the A1 mouth, through the control valve oil sump tank, this is the operating mode that hoists normally.
2. when allowing telescopic crane boom be parked in the air, the 3-position 4-way control valve is changed to the neutral position, cut-out pressure oil enters the channel of this valve master hydraulic fluid port A, stops to the oil hydraulic cylinder fuel feeding, under piston rod deadweight and load effect, tries hard to make piston rod descending.At this moment, main valve plug 12 and control spool 8 are being close under the effect of spring 11 and 7 on valve body 10 and 6, and the channel by between main hydraulic fluid port A and main hydraulic fluid port B cuts off the descending oil stream of hoist, stops the piston rod retraction, and telescopic crane boom is rested in the air.Described main valve plug of this valve and control spool adopt cone valve structure, can reduce leakage effectively, prevent that weight from falling under the deadweight effect, guarantee safe operation.
3. hoist bears a heavy burden when descending, the 3-position 4-way control valve is changed to the position of left end.At this moment, the rod chamber of the amplitude of oscillation cylinder of hoist communicates with the A1 mouth of control valve, the K mouth of this valve; Pressure oil communicates with the rod chamber and the control port K of amplitude of oscillation cylinder by the hydraulic fluid port A1 of control valve.The pressure oil of control port K affacts the right chamber of piston 13, overcomes the pretightening force and the hydraulic coupling that acts on spool 12 left sides of spring 11, promotes main valve plug 12 and moves to left; The spool 8 of control valve tightly sticks together with valve piece 6 under the effect of spring force and hydraulic coupling.At this moment, the oil of B mouth enters the f chamber through oil-through hole g on the one hand, acts on the left end of control piston 3, under the effect of hydraulic coupling, overcome the pretightening force of spring 18 or spring 11, the spool 19 that promotes the adaptive load valve moves right, and the orifice size (aperture e) between d chamber and the c chamber is reduced.At this moment, the fluid of amplitude of oscillation cylinder rodless cavity arrives the A mouth by B mouth, d chamber, aperture e, c chamber, hollow nut 9, b chamber, a chamber, through the B1 mouth oil sump tank of control valve.Descending with hoist, act on the load variations on the amplitude of oscillation cylinder, make the variation in pressure of amplitude of oscillation cylinder rodless cavity.When the pressure of amplitude of oscillation cylinder rodless cavity raise, the pressure that acts on control piston 3 left ends also raise, and will push away spool 19 to the right, and restriction e is reduced, and under the constant situation of dependable flow, the pressure in d chamber will raise, with load matched.On the contrary, when the pressure of amplitude of oscillation cylinder rodless cavity reduced, the pressure that acts on control piston 3 left ends also reduced, under the effect of spring 18 and 16, will push away spool 19 left, restriction e is increased, under the constant situation of dependable flow, the pressure in d chamber will reduce, with load matched.
Claims (7)
1. a hydraulically balanced valve that adapts to load variations automatically is characterized in that comprising main valve, adaptive load valve and control valve, each valve includes valve body, spool and two chambeies, front and back, main valve and control valve are cone valve structure, the adaptive load valve is a sliding valve structure, outer oil-collecting hole A, B, K, X are arranged on the valve body, oil pocket a, b are arranged in the main valve, and corresponding with the A mouth is a chamber; Main valve is made up of main valve plug 12, valve body 10, spring 11, nut 9, and spool tightly is attached to by spring on the inner conical surface of valve body, and control oil enters the right-hand member of piston 13 by the K mouth, opens main valve; The adaptive load valve is positioned at the main valve left end, form by valve pocket 15, spool 19, weak spring 16, spring seat 17, strong spring 18 and control piston 3, gapped cooperation between spool 19 and the valve pocket 15, in spool circumferential a series of aperture e is arranged, spool 19 tightly sticks together by weak spring 16, strong spring 18 and spring seat 17 with valve pocket 15, the adaptive load valve includes a strong spring 18 and a weak spring 16, two springs link together by spring seat 17, low pressure stage weak spring 16 works, high pressure section spring seat 17 automatic spacings, strong spring 18 works; Control valve is in parallel with main valve, is made up of control spool 8, spring 7, valve piece 6 and nut 5, links together by screw and main valve body.
2. according to the hydraulically balanced valve of right 1 described automatic adaptation load variations, it is characterized in that the spool 19 of described adaptive load valve is a cartridge type, one end sealing has 3～5 roads sulculus that goes in ring near the outside of closed end; The other end opens wide, and there is a series of circumferential aperture e its outside, the valve pocket 15 supporting with it, and its internal diameter equates gapped cooperation with the external diameter nominal size of spool 19.
3. according to the hydraulically balanced valve of right 1 described automatic adaptation load variations, it is characterized in that described main valve is a Pilot operated check valve, adopt cone valve structure, main valve plug is attached on the valve port of valve body 10 tightly by hollow nut 9 and spring 11.
4. according to the hydraulically balanced valve of right 1 described automatic adaptation load variations, it is characterized in that described control valve is an one-way valve, adopt cone valve structure.
5. according to the hydraulically balanced valve of right 1 described automatic adaptation load variations, it is characterized in that described adaptive load valve has one to be the drain tap X that makes things convenient for the design of adaptive load valve spring 16 and 18.
6. according to the hydraulically balanced valve of right 1 described automatic adaptation load variations, it is characterized in that the promising flow of described adaptive load valve, make the initial value of restriction e and the adjustable lever 1 of flow system flow coupling according to system.
7. according to the hydraulically balanced valve of right 2 described automatic adaptation load variations, it is characterized in that the circumferential aperture e of described adaptive load valve, the pressure reduction in orifice size vertically and d chamber and c chamber is hyperbolic relation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200610102007XA CN100441885C (en) | 2006-10-10 | 2006-10-10 | Hydraulic balance valve capable of automatically adapting load change |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200610102007XA CN100441885C (en) | 2006-10-10 | 2006-10-10 | Hydraulic balance valve capable of automatically adapting load change |
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| Publication Number | Publication Date |
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| CN1945028A true CN1945028A (en) | 2007-04-11 |
| CN100441885C CN100441885C (en) | 2008-12-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNB200610102007XA Expired - Fee Related CN100441885C (en) | 2006-10-10 | 2006-10-10 | Hydraulic balance valve capable of automatically adapting load change |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100513804C (en) * | 2007-05-19 | 2009-07-15 | 浙江圣邦机械有限公司 | Self-aligning dual hydraulic ball valve |
| CN102032230A (en) * | 2010-12-04 | 2011-04-27 | 林友根 | Throttling valve |
| CN102971614A (en) * | 2010-06-28 | 2013-03-13 | Ta海德罗尼克斯有限责任公司 | Valve assembly for a differential pressure sensor with safety valve |
| CN106949110A (en) * | 2017-04-10 | 2017-07-14 | 四川长江液压件有限责任公司 | A kind of pump flow stabilizing valve |
| CN108661964A (en) * | 2018-06-29 | 2018-10-16 | 杭州诺祥科技有限公司 | A kind of side valve type asymmetric cylinder bidirectional hydraulic balance system |
| CN108709000A (en) * | 2018-08-22 | 2018-10-26 | 佛山信卓派思机械科技有限公司 | A kind of flow type balanced valve of setting pressure automatic adjustment |
| CN108825574A (en) * | 2018-07-20 | 2018-11-16 | 太原理工大学 | A kind of hydraulically balanced valve of automatic adaptation load variation and changes in flow rate |
| CN109611403A (en) * | 2019-01-23 | 2019-04-12 | 洛阳理工学院 | A kind of overflow type hydraulically balanced valve with vibration-damping function |
| CN110374949A (en) * | 2018-04-13 | 2019-10-25 | 丹佛斯动力系统（浙江）有限公司 | Valve and hydraulic system with the valve |
| CN110513345A (en) * | 2019-09-04 | 2019-11-29 | 太原理工大学 | A kind of load memory valve |
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| US3884262A (en) * | 1970-09-11 | 1975-05-20 | Koppen Lethem Trading | Pressure control device for a hydraulic circuit |
| JPS56156570A (en) * | 1980-05-06 | 1981-12-03 | Aisin Seiki Co Ltd | Check valve combined with balance piston type relief valve |
| JPS5757971A (en) * | 1980-09-20 | 1982-04-07 | Aisin Seiki Co Ltd | Combined valve |
| CN86201814U (en) * | 1986-03-27 | 1987-06-24 | 城乡建设环境保护部长沙建筑机械研究所 | Balanced valve |
| US6135135A (en) * | 1997-12-12 | 2000-10-24 | Alliedsignal Inc. | Force balanced proportional bypass valve |
| CN1170067C (en) * | 2001-12-07 | 2004-10-06 | 卢永松 | Hydraulic balancing valve |
| CN2804450Y (en) * | 2005-06-01 | 2006-08-09 | 刘恒海 | Balancing valve |
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- 2006-10-10 CN CNB200610102007XA patent/CN100441885C/en not_active Expired - Fee Related
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100513804C (en) * | 2007-05-19 | 2009-07-15 | 浙江圣邦机械有限公司 | Self-aligning dual hydraulic ball valve |
| CN102971614A (en) * | 2010-06-28 | 2013-03-13 | Ta海德罗尼克斯有限责任公司 | Valve assembly for a differential pressure sensor with safety valve |
| CN102971614B (en) * | 2010-06-28 | 2014-12-17 | Ta海德罗尼克斯有限责任公司 | Valve assembly for a differential pressure sensor with safety valve |
| CN102032230A (en) * | 2010-12-04 | 2011-04-27 | 林友根 | Throttling valve |
| CN102032230B (en) * | 2010-12-04 | 2013-04-10 | 林友根 | Throttling valve |
| CN106949110A (en) * | 2017-04-10 | 2017-07-14 | 四川长江液压件有限责任公司 | A kind of pump flow stabilizing valve |
| CN110374949A (en) * | 2018-04-13 | 2019-10-25 | 丹佛斯动力系统（浙江）有限公司 | Valve and hydraulic system with the valve |
| CN110374949B (en) * | 2018-04-13 | 2020-12-04 | 丹佛斯动力系统（浙江）有限公司 | Valve and hydraulic system with same |
| CN108661964A (en) * | 2018-06-29 | 2018-10-16 | 杭州诺祥科技有限公司 | A kind of side valve type asymmetric cylinder bidirectional hydraulic balance system |
| CN108825574A (en) * | 2018-07-20 | 2018-11-16 | 太原理工大学 | A kind of hydraulically balanced valve of automatic adaptation load variation and changes in flow rate |
| CN108825574B (en) * | 2018-07-20 | 2020-01-03 | 太原理工大学 | Hydraulic balance valve automatically adapting to load change and flow change |
| CN108709000B (en) * | 2018-08-22 | 2019-11-15 | 浙江斯丹特阀门股份有限公司 | A kind of flow type balanced valve of setting pressure automatic adjustment |
| CN108709000A (en) * | 2018-08-22 | 2018-10-26 | 佛山信卓派思机械科技有限公司 | A kind of flow type balanced valve of setting pressure automatic adjustment |
| CN109611403A (en) * | 2019-01-23 | 2019-04-12 | 洛阳理工学院 | A kind of overflow type hydraulically balanced valve with vibration-damping function |
| CN109611403B (en) * | 2019-01-23 | 2023-08-15 | 洛阳理工学院 | Overflow type hydraulic balance valve with vibration reduction function |
| CN110513345A (en) * | 2019-09-04 | 2019-11-29 | 太原理工大学 | A kind of load memory valve |
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| CN100441885C (en) | 2008-12-10 |
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Granted publication date: 20081210 Termination date: 20111010 |