CN103742473A - Split type pilot load control valve - Google Patents
Split type pilot load control valve Download PDFInfo
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- CN103742473A CN103742473A CN201310749304.3A CN201310749304A CN103742473A CN 103742473 A CN103742473 A CN 103742473A CN 201310749304 A CN201310749304 A CN 201310749304A CN 103742473 A CN103742473 A CN 103742473A
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- valve
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- 239000003921 oils Substances 0.000 claims abstract description 29
- 230000015572 biosynthetic process Effects 0.000 claims description 11
- 238000005755 formation reactions Methods 0.000 claims description 11
- 230000000694 effects Effects 0.000 abstract description 3
- 210000002832 Shoulder Anatomy 0.000 description 5
- 239000010720 hydraulic oils Substances 0.000 description 3
- 238000007906 compression Methods 0.000 description 2
- 230000003247 decreasing Effects 0.000 description 2
- 238000000034 methods Methods 0.000 description 2
- 238000010587 phase diagrams Methods 0.000 description 2
- 230000001737 promoting Effects 0.000 description 2
- 230000000630 rising Effects 0.000 description 2
- 238000010586 diagrams Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Abstract
Description
Technical field
The present invention relates to hydraulic control component, especially relate to a kind of split type guide's load control valve.
Background technique
In hydraulic system applications such as engineering machinery, crane gear and winch, can often there is the situation that load force direction is consistent with load movement direction, this kind of load is called as and surmounts load (negative load).Bear the hydraulic system that surmounts load, need to have special control valve to control from the flow of the hydraulic oil in load flow oil return source, thus the speed that control load is transferred, and this kind of control valve is commonly referred to as load control valve or equilibrium valve.Because induced pressure is higher, loading condition is complicated, and the metering characteristics of load control valve directly determine speed control characteristic and the speed stability of hydraulic system.
Yet, at crane variable-amplitude hydraulic system even load pressure, along with load, to transfer and in the application that increases, normal load control valve often exists along with load is transferred, induced pressure increases and then lowering velocity increases the problem of even stall.In these are applied, load control valve becomes the bottleneck of hydraulic system performance, is badly in need of the load control valve that design can be resisted the lowering velocity increase causing because induced pressure raises.
In view of this, apply new principle, new method, development is applicable to exist the speed increase novel load control valve causing because induced pressure raises that is highly resistant to of the hydraulic system that surmounts load to have important practical meaning in engineering.
Summary of the invention
In order to realize the control that has load lowering velocity in the hydraulic system that surmounts load in background technique, especially overcome the existing problem of conventional load control valve of the lowering velocity increase causing because induced pressure raises, the object of the present invention is to provide a kind of split type guide's load control valve, owing to adopting leading type structure, this valve acts on control piston-pilot valve core assembly by pilot pressure, indirectly control main valve plug motion, the hydraulic system that surmounts load for existence, this load control valve can accurately be controlled load lowering velocity.Overcompensation function, will can, in the application that crane variable-amplitude hydraulic system even load pressure increases along with transferring, effectively suppress induced pressure and increase the speed increase problem of bringing this valve.
The technical solution used in the present invention is:
Main valve housing of the present invention is installed in the cylindrical hole of main valve body, main valve plug small end is through main valve housing and be positioned at oil back chamber, the large end of main valve plug and main valve housing endoporus are for being slidably matched, the large end of main spool spring seat is placed in the large end step hole of main valve housing, and compress the large end of main valve housing, main spool spring seat small end is pressed on the rear portion of main valve housing by main valve end cap, one end of main valve Returnning spring is placed in the bottom, hole of main valve plug, and the other end of main valve Returnning spring is placed in the bottom, hole of main spool spring seat;
Guide's valve pocket is installed in the cylindrical hole of guide valve blocks one end, main valve housing bottom forms oil back chamber with main valve body opening and guide's valve pocket bottom jointly with pilot valve body opening, guide's spool small end is through guide's valve pocket and be positioned at oil back chamber, the large end of guide's spool is placed in guide's valve pocket and forms and be slidably matched, the large end of the tight guide's valve pocket of the large side pressure of pilot valve spring seat, the small end of pilot valve spring seat is pressed in guide valve blocks cylindrical hole by pilot valve right end cap, one end of pilot valve Returnning spring is set on the large end shoulder of guide's spool, the other end of pilot valve Returnning spring is placed in the bottom, hole of pilot valve spring seat, overcompensation damping is installed in the hole near guide's spool of the large end of pilot valve Returnning spring one side, the large bottom of main valve plug portion, the large bottom of main valve housing portion, main valve body opening, main valve end cap, the large bottom of guide's spool portion, the large bottom of guide's valve pocket portion, pilot valve body opening and pilot valve right end cap surround control sensitive cavity jointly, between guide valve blocks and main valve body, be bolted,
Control piston is placed in the cylindrical hole of the guide valve blocks the other end and with guide valve blocks and forms and be slidably matched, and the small end of control piston withstands on the small end through guide's spool of guide's valve pocket; One end of control spring withstands on the cylindrical hole bottom of guide valve blocks, and the other end of control spring withstands on control piston shoulder, and control piston damping is installed in control piston hole; Pilot valve left end cap is arranged on guide valve blocks by bolt, and pushes down the large end of control piston; Control piston, guide valve blocks and pilot valve left end cap coordinate formation control chamber jointly, and the center hole of pilot valve left end cap is control port X, and control port X is communicated with control chamber;
Main valve body cylindrical hole middle part, the large end of main valve plug outside, main valve housing, guide valve blocks cylindrical hole middle part, the large end of guide's spool outside, guide's valve pocket coordinate formation load cavity jointly; Main valve body is provided with return opening A and is communicated with oil back chamber, and main valve body is provided with load hydraulic fluid port B and is communicated with load cavity; Oil back chamber can be communicated with load cavity by main valve plug middle part valve port; Control sensitive cavity and be communicated with load cavity by the large end rectangle groove of main valve plug, controlling sensitive cavity can be communicated with load cavity by the valve port of the large end of guide's spool, and controlling sensitive cavity can be communicated with guide's valve core cavity by overcompensation damping internal holes; Guide's spool cylindrical hole, overcompensation damping and guide's valve pocket coordinate formation guide valve core cavity, and guide's valve core cavity can be communicated with oil back chamber by guide's spool small end valve port; Guide valve blocks coordinates formation draining chamber with control piston, guide valve blocks radially drain tap L is communicated with draining chamber; Aperture left side in control piston damping is control chamber, and right side is draining chamber.
Described guide's spool is parallel with main valve plug axis, and guide's spool is identical with the little extreme direction of main valve plug.
Described guide's spool is coaxial with control piston, and guide's spool is relative with control piston small end.
On described guide's spool, overcompensation damping is installed, makes load control valve there is overcompensation function.
The beneficial effect that the present invention has is:
For existence, surmount in the hydraulic system of load, this load control valve can accurately be controlled the flow by load control valve, and then the speed that load is transferred is carried out the control of efficiently and accurately; Owing to adopting leading type structure, this valve acts on control piston-pilot valve core assembly by pilot pressure, indirectly controls main valve plug motion, surmounts the hydraulic system of load for existence, and this load control valve can accurately be controlled load lowering velocity.Because the overcompensation damping structure of guide's spool, this valve has overcompensation function, and this valve can, in the application that crane variable-amplitude hydraulic system even load pressure increases along with transferring, effectively be suppressed induced pressure and increase the speed increase problem of bringing.The matching design of guide's spool and guide's valve pocket, when guide's spool is closed, load cavity is directly linked up with controlling sensitive cavity, raises rapidly, thereby promote main valve plug quick closedown thereby make to control sensitive cavity pressure, makes load control valve have quick closedown function.
Accompanying drawing explanation
Fig. 1 is structural principle schematic diagram of the present invention.
Fig. 2 is the sectional drawing in A-A cross section in Fig. 1.
Phase diagram when Fig. 3 is unidirectional the opening of load rising load control valve.
Fig. 4 is the phase diagram of load decline load control valve guide while opening.
Fig. 5 is the partial enlarged view at C place in Fig. 1.
Fig. 6 is the partial enlarged view at D place in Fig. 1.
In figure: 1, pilot valve left end cap, 2, control piston, 3, control piston damping, 4, guide valve blocks, 5, control spring, 6, guide's spool, 7, guide's valve pocket, 8, overcompensation damping, 9, pilot valve spring seat, 10, pilot valve Returnning spring, 11, pilot valve right end cap, 12, main valve plug, 13, main valve housing, 14, main valve Returnning spring, 15, main spool spring seat, 16, main valve end cap, 17, main valve body, 18, control chamber, 19, draining chamber, 20, oil back chamber, 21, guide's valve core cavity, 22, load cavity, 23, control sensitive cavity.
Embodiment
Below in conjunction with drawings and Examples, the invention will be further described.
As shown in Figure 1, the present invention includes pilot valve left end cap 1, control piston 2, control piston damping 3, guide valve blocks 4, control spring 5, guide's spool 6, guide's valve pocket 7, overcompensation damping 8, pilot valve spring seat 9, pilot valve Returnning spring 10, pilot valve right end cap 11, main valve plug 12, main valve housing 13, main valve Returnning spring 14, main spool spring seat 15, main valve end cap 16 and main valve body 17.
As Fig. 1, shown in Fig. 2, main valve housing 13 is installed in the cylindrical hole of main valve body 17, main valve plug 12 small ends are through main valve housing 13 and be positioned at oil back chamber 20, the large end of main valve plug 12 and main valve housing 13 endoporus are for being slidably matched, the large end of main spool spring seat 15 is placed in the large end step hole of main valve housing 13, and compress the large end of main valve housing 13, main spool spring seat 15 small ends are pressed on the rear portion of main valve housing 13 by main valve end cap 16, one end of main valve Returnning spring 14 is placed in the bottom, hole of main valve plug 12, the other end of main valve Returnning spring 14 is placed in the bottom, hole of main spool spring seat 15, guide's valve pocket 7 is installed in guide valve blocks 4 cylindrical holes, main valve housing 13 bottoms and main valve body 17 holes and guide's valve pocket 7 bottoms and guide valve blocks 4 holes form oil back chamber 20 jointly, guide's spool 6 small ends are through guide's valve pocket 7 and be positioned at oil back chamber 20, the large end of guide's spool 6 is placed in the interior formation of guide's valve pocket 7 and is slidably matched, overcompensation damping 8 is installed in the hole near guide's spool 6 of the large end of pilot valve Returnning spring 10 1 side, the large end of the tight guide's valve pocket 7 of pilot valve spring seat 9 large side pressure, the small end of pilot valve spring seat 9 is pressed in guide valve blocks 4 cylindrical holes by pilot valve right end cap 11, one end of pilot valve Returnning spring 10 is set on the large end shoulder of guide's spool 6, the other end of pilot valve Returnning spring 10 is placed in the bottom, hole of pilot valve spring seat 9, the large bottom of main valve plug 12 portion, the large bottom of main valve housing 13 portion, main valve body 17 holes, main valve end cap 16, the large bottom of guide's spool 6 portion, the large bottom of guide's valve pocket 7 portion, guide valve blocks 4 holes, pilot valve right end cap 11 surround jointly controls sensitive cavity 23, between guide valve blocks 4 and main valve body 17, be bolted.Control piston damping 3 is installed in control piston 2 holes, and control piston 2 is placed in the cylindrical hole of guide valve blocks 4 and with guide valve blocks 4 and forms and be slidably matched, and the small end of control piston 2 withstands on the small end through guide's spool 6 of guide's valve pocket 7; One end of control spring 5 withstands on the cylindrical hole bottom of guide valve blocks 4, and the other end of control spring 5 withstands on control piston 2 shoulders, and pilot valve left end cap 1 is arranged on guide valve blocks 4 by bolt, and pushes down the large end of control piston 2; The common formation control chamber 18 that coordinates of control piston 2, guide valve blocks 4 and pilot valve left end cap 1, the center of pilot valve left end cap 1 is provided with control port X, and control port X is communicated with control chamber 18.
As shown in Figure 1, Figure 2, Figure 3 shows, main valve body 17 is provided with return opening A and is communicated with oil back chamber 20, and main valve body 17 is provided with load hydraulic fluid port B and is communicated with load cavity 22; Main valve body 17 cylindrical hole middle parts, the large end of main valve plug 12 outside, main valve housing 13, guide valve blocks 4 cylindrical hole middle parts, the large end of guide's spool 6 outside, common cooperation of guide's valve pocket 7 form load cavity 22, and oil back chamber 20 can be communicated with load cavity 22 by main valve plug 12 middle part valve ports; Control sensitive cavity 23 and be communicated with load cavity 22 by the large end rectangle groove of main valve plug 12, controlling sensitive cavity 23 can be communicated with load cavity 22 by the valve port of guide's spool 6 large ends, and controlling sensitive cavity 23 can be communicated with guide's valve core cavity 21 by overcompensation damping 8 internal holes; Guide's spool 6 cylindrical holes, overcompensation damping 8 and guide's valve pocket 7 coordinate formation guide valve core cavity 21, and guide's valve core cavity 21 can be communicated with oil back chamber 20 by guide's spool 6 small end valve ports; Guide valve blocks 4 coordinates formation draining chamber 19 with control piston 2, guide valve blocks 4 radially drain tap L is communicated with draining chamber 19.
Described guide's spool 6 is parallel with main valve plug 12 axis, and guide's spool 6 is identical with the little extreme direction of main valve plug 12.
Described guide's spool 6 is coaxial with control piston 2, and guide's spool 6 is relative with control piston 2 small ends.
On described guide's spool 6, overcompensation damping 8 is installed, makes load control valve there is overcompensation function.Along with induced pressure increases, the hydraulic fluid flow rate by load control valve reduces, the effect of the safety of proof load and hydraulic system.
The matching design of guide's spool 6 and guide's valve pocket 7, when guide's spool 6 is closed, load cavity 22 is directly linked up with controlling sensitive cavity 23, thereby make to control sensitive cavity 23 pressure, raises rapidly, thereby promote main valve plug 12 quick closedowns, make load control valve there is quick closedown function.
As shown in Figure 1, the split type guide's load control valve of the present invention mainly comprises main valve plug assembly, pilot valve core assembly, control piston assembly and valve component.Main valve plug assembly comprises main valve plug 12, main valve housing 13 and main valve Returnning spring 14, main valve plug is placed in main valve housing, and can in main valve housing, move vertically, main valve Returnning spring 14 one end withstand on the bottom of main valve plug endoporus, wherein the oil back chamber 20 of main valve plug left end communicates with load control valve return opening A, load cavity 22 communicates with load control valve load hydraulic fluid port B, and main valve plug right-hand member cavity volume is for controlling sensitive cavity 23; Pilot valve core assembly consists of guide's spool 6, guide's valve pocket 7, overcompensation damping 8 and pilot valve Returnning spring 10, guide's spool is placed in guide's valve pocket, and formerly in guide valve bushing, move vertically, overcompensation damping 8 is installed on guide's spool afterbody by screw thread, pilot valve Returnning spring one end is enclosed within guide's spool afterbody ladder place, and withstand its convex shoulder, and wherein overcompensation damping left end cavity volume is guide's valve core cavity 21, overcompensation damping right-hand member cavity volume is for controlling sensitive cavity 23; Control piston assembly consists of control piston 2 and control spring 5, control piston is placed in guide valve blocks cylindrical hole and can moves vertically therein, guide valve blocks cylindrical hole bottom is withstood in control spring one end, the other end is enclosed within on control piston and withstands control piston, wherein the control chamber 18 of control piston left end communicates with load control valve control port X, and the draining chamber 19 of control piston right-hand member communicates with load control valve drain tap L; Valve component consists of main valve body 17, guide valve blocks 4, main valve end cap 16, pilot valve left end cap 1 and pilot valve right end cap 11, main valve end cap and main valve body are threaded connection, main valve body is connected by 6 interior hexagonal cylindrical hook bolts with guide valve blocks, pilot valve left end cap is connected by 4 interior hexagonal cylindrical hook bolts with guide valve blocks, and pilot valve right end cap and guide valve blocks are threaded connection.
Fig. 2 has shown the be communicated with situation of load control valve load hydraulic fluid port B with load cavity 22.
When Fig. 3 is load rising, the state of load control valve during as one-way valve opens, now hydraulic oil enters load control valve from A mouth, promoting main valve plug 12 compression main valve Returnning springs 14 moves to main valve end cap 16 directions, valve port is opened, and hydraulic oil enters load cavity 22 through valve port, and then flows out from B mouth, load control valve is during as one-way valve opens, and guide's spool 6, control piston 2 are motionless in original position.
Figure 4 shows that when load declines, state when load control valve guide opens, first, pilot control pressure oil enters control chamber 18 from control port X, promoting control piston 2 compression control springs 5 moves to guide's spool 6 directions, under the promotion of control piston 2, guide's spool 6 moves to pilot valve right end cap 11 directions, poppet port between guide's spool 6 and guide's valve pocket 7 is opened, link up guide's valve core cavity 21 and oil back chamber 20, guide's valve core cavity 21 pressure decreaseds, owing to controlling sensitive cavity 23, be connected by overcompensation damping 8 with guide's valve core cavity 21, so control sensitive cavity 23 pressure decreaseds, main valve plug 12 stress balances are broken, main valve plug 12 moves to main valve end cap 16 directions, primary valve is opened, the pressure oil of B mouth is by load cavity 22, primary valve enters oil back chamber 20, and then flow out from load control valve A mouth.
Fig. 5 is the partial enlarged view at C place in Fig. 1, load cavity 22 and the situation that is communicated with of controlling sensitive cavity 23 have been shown, when guide valve core 6 moves right in the ban, load cavity 22 is blocked with control being communicated with of sensitive cavity 23, when guide valve core 6 sets back in the ban, load cavity 22 is communicated with again with control sensitive cavity 23, now the pressure oil in load cavity enters and controls sensitive cavity 23, the pressure of controlling sensitive cavity 23 raises, thereby promote main valve plug 12, to the direction away from main valve end cap 16, move, and then load control valve is closed.
Fig. 6 is the partial enlarged view at D place in Fig. 1, the details that has shown the large end valve mouth of main valve plug, when guide opens, the pressure of controlling sensitive cavity 23 reduces because of opening of guide's spool 6, main valve plug stress balance is broken, main valve plug moves to the direction of main valve end cap 16, now the large end valve of the main valve plug flow area of making a slip of the tongue increases, the pressure oil of load cavity 22 enters and controls sensitive cavity 23 through this valve port, controlling sensitive cavity pressure raises, main valve plug reaches stress balance again, and then is stabilized in certain enable possition.
Claims (4)
Priority Applications (1)
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CN201310749304.3A CN103742473B (en) | 2013-12-31 | 2013-12-31 | Split type pilot load control valve |
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CN201310749304.3A CN103742473B (en) | 2013-12-31 | 2013-12-31 | Split type pilot load control valve |
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CN103742473A true CN103742473A (en) | 2014-04-23 |
CN103742473B CN103742473B (en) | 2015-12-09 |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104358728A (en) * | 2014-11-04 | 2015-02-18 | 浙江大学 | Secondary load control valve integrating overflow function on pilot valve core |
CN104454736A (en) * | 2014-12-15 | 2015-03-25 | 山东华伟液压设备制造有限公司 | Load holding valve and running method thereof |
CN106050775A (en) * | 2016-06-11 | 2016-10-26 | 宁波文泽机电技术开发有限公司 | Pilot control valve of improved structure |
CN106122144A (en) * | 2016-06-29 | 2016-11-16 | 宁波文泽机电技术开发有限公司 | The pilot-actuated valve operated steadily |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105971956B (en) * | 2016-05-31 | 2017-11-10 | 盐城市锦瑞石油机械有限公司 | A kind of pilot-actuated valve |
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CN2804450Y (en) * | 2005-06-01 | 2006-08-09 | 刘恒海 | Balancing valve |
CN202732526U (en) * | 2012-08-20 | 2013-02-13 | 宁波市博尔法液压有限公司 | Combined hydraulic balance valve |
WO2013059777A1 (en) * | 2011-10-21 | 2013-04-25 | Sun Hydraulics Corporation | Dynamically adjusting counterbalance valve |
CN103343829A (en) * | 2013-07-24 | 2013-10-09 | 南京工业大学 | Balance valve and testing system thereof |
CN203655762U (en) * | 2013-12-31 | 2014-06-18 | 浙江大学 | Split type pilot load control valve |
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2013
- 2013-12-31 CN CN201310749304.3A patent/CN103742473B/en active IP Right Grant
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CN2247735Y (en) * | 1995-01-27 | 1997-02-19 | 长沙交通学院 | Combined integrated block hydraulically balanced valve |
US5878647A (en) * | 1997-08-11 | 1999-03-09 | Husco International Inc. | Pilot solenoid control valve and hydraulic control system using same |
JP2001153170A (en) * | 1999-11-30 | 2001-06-08 | Sanwa Tekki Corp | Constant pressure valve and hydraulic vibration damping device |
CN1350125A (en) * | 2001-12-07 | 2002-05-22 | 卢永松 | Hydraulic balancing valve |
CN1587718A (en) * | 2004-08-04 | 2005-03-02 | 浙江大学 | Pure water unloading overflow valve |
CN2804450Y (en) * | 2005-06-01 | 2006-08-09 | 刘恒海 | Balancing valve |
WO2013059777A1 (en) * | 2011-10-21 | 2013-04-25 | Sun Hydraulics Corporation | Dynamically adjusting counterbalance valve |
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CN103343829A (en) * | 2013-07-24 | 2013-10-09 | 南京工业大学 | Balance valve and testing system thereof |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104358728A (en) * | 2014-11-04 | 2015-02-18 | 浙江大学 | Secondary load control valve integrating overflow function on pilot valve core |
CN104454736A (en) * | 2014-12-15 | 2015-03-25 | 山东华伟液压设备制造有限公司 | Load holding valve and running method thereof |
CN104454736B (en) * | 2014-12-15 | 2016-06-15 | 山东华伟液压科技有限公司 | A kind of load holding valve and method of work thereof |
CN106050775A (en) * | 2016-06-11 | 2016-10-26 | 宁波文泽机电技术开发有限公司 | Pilot control valve of improved structure |
CN106122144A (en) * | 2016-06-29 | 2016-11-16 | 宁波文泽机电技术开发有限公司 | The pilot-actuated valve operated steadily |
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