CN104358286A - Hydraulic control valve with shunt and converging selectable function and loader fixed and variable delivery hydraulic system - Google Patents
Hydraulic control valve with shunt and converging selectable function and loader fixed and variable delivery hydraulic system Download PDFInfo
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- CN104358286A CN104358286A CN201410627890.9A CN201410627890A CN104358286A CN 104358286 A CN104358286 A CN 104358286A CN 201410627890 A CN201410627890 A CN 201410627890A CN 104358286 A CN104358286 A CN 104358286A
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- fluid port
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Abstract
The invention relates to a hydraulic control valve with a shunt and converging selectable function and aims at solving the problems of energy loss and steering vibration of the existing loader fixed and variable delivery hydraulic system. According to the hydraulic control valve with the shunt and converging selectable function, disclosed by the invention, when a first hydraulic control valve is at a right position, the oil inlet of the first hydraulic control valve is unidirectionally communicated to a C port through a third one-way valve, and when the first hydraulic control valve is at a left position, the oil inlet of the first hydraulic control valve is communicated with the oil inlet of a second hydraulic control valve; the left hydraulic control end and the right hydraulic control of the second hydraulic control valve are respectively communicated with the C port via throttle orifices through the inlet of a first one-way valve; when the second hydraulic control valve is at the left position, the oil inlet of the second hydraulic control valve is communicated to the C port through the first one-way valve, and when the second hydraulic control valve is at the right position, the oil inlet of the second hydraulic control valve is unidirectionally communicated to the C port through the first one-way valve and unidirectionally communicated to an E port through the second one-way valve. When the hydraulic control valve with the shunt and converging selectable function is arranged in a loader fixed and variable delivery hydraulic system, the problems of the energy loss and the steering vibration can be avoided.
Description
Technical field
The present invention relates to a kind of Hydraulic Elements, particularly relate to a kind of interflow selection function pilot operated valve device and loader of dividing and determine variable delivery hydraulic system.
Background technology
The load-sensitive of current employing turns to combining hydraulic system, and its converging valve used is generally pressure-gradient control valve, and when hydraulic work system, pump is preferentially carried out oily supply steering hydraulic system by this pressure-gradient control valve, and unnecessary flow then collaborates in the middle of main valve oil circuit.When its be applied to coupling single argument pump and open meta banked direction control valves determine variable delivery hydraulic system time, hydraulic system is under Part load, actuator does not carry out action or carries out fine motion work, variable pump can be caused to be in huge discharge for oil condition, unnecessary flow can flow back to fuel tank by holding meta banked direction control valves, produces bit-loss and restriction loss greatly; Thus, cause hydraulic system to produce very large heat, energy consumption is large.In order to solve and avoid this problem, for coupling variable pump and open meta banked direction control valves determine variable delivery hydraulic system, whether the load hydraulic control mouth of normal precedence valve works according to hydraulic system of working by current existence makes it be in cut-off state, but consequently leads to steering hydraulic system instability of flow and turn to jitter problem.
Summary of the invention
The object of the invention is to can only to realize common preferential oil supply function for existing pressure-gradient control valve cause the energy loss of determining variable delivery hydraulic system and turn to jitter problem and provide a kind of loader possessing point pilot operated valve device of collaborating selectable punction and have this pilot operated valve device to determine variable delivery hydraulic system.
The present invention is the technical scheme realizing its object is such: structure a kind of point of interflow selection function pilot operated valve device, it comprises the first pilot operated valve device, second pilot operated valve device, first one way valve, second one way valve and the 3rd one way valve, first segment discharge orifice, second section discharge orifice, 3rd throttle orifice and P hydraulic fluid port, b hydraulic fluid port, T hydraulic fluid port, a hydraulic fluid port, C hydraulic fluid port, E hydraulic fluid port, P hydraulic fluid port is communicated in the oil-in of the first pilot operated valve device, b hydraulic fluid port and T hydraulic fluid port are communicated in the left and right hydraulic control end of the first pilot operated valve device respectively, when first pilot operated valve device is in right position its oil-in through the 3rd one way valve to C hydraulic fluid port one-way conduction, when first pilot operated valve device is in left position, its oil-in is communicated in the oil-in of the second pilot operated valve device, a hydraulic fluid port is communicated in the left hydraulic control end of the second pilot operated valve device through first segment discharge orifice, the left hydraulic control end of the second pilot operated valve device is communicated in the entrance of the first one way valve through the 3rd throttle orifice through second section discharge orifice, right hydraulic control end, the outlet of the first one way valve is in C hydraulic fluid port, when second pilot operated valve device is in left position its oil-in through the first one way valve to the conducting of C hydraulic fluid port, when the second pilot operated valve device is in right position its oil-in through the first one way valve to C hydraulic fluid port one-way conduction and through the second one way valve to E hydraulic fluid port one-way conduction.In above-mentioned point of interflow selection function pilot operated valve device, the right hydraulic control end of the first pilot operated valve device is spring cavity, and the T hydraulic fluid port be communicated with this spring cavity is oil return opening.The left hydraulic control end of the second pilot operated valve device is spring cavity.
The present invention is another technical scheme realizing its object is such: construct a kind of loader and determine variable delivery hydraulic system, comprise variable pump, steering gear, flux amplification valve, banked direction control valves, comprise aforesaid point of interflow selection function pilot operated valve device in addition, the a hydraulic fluid port of interflow selection function pilot operated valve device is divided to be communicated in the LS feedback port of steering gear, what C hydraulic fluid port was communicated in flux amplification valve turns to oil-in, E hydraulic fluid port is communicated in the working oil entrance of banked direction control valves, P hydraulic fluid port is communicated in the oil-out of variable pump, and b hydraulic fluid port is communicated in the pilot pressure oil circuit of banked direction control valves.Determine in variable delivery hydraulic system at loader of the present invention: constant displacement pump is by boom cylinder, the rotary ink tank fuel feeding of banked direction control valves to loader, and banked direction control valves controls by pilot valve.
When the equal attonity of the pilot valve of steering gear and banked direction control valves, because point fuel-displaced C hydraulic fluid port of interflow selection function pilot operated valve device and fuel-displaced E hydraulic fluid port are all cut off, the load-sensitive mouth no signal of variable pump, variable pump is fuel feeding not, avoids banked direction control valves and opens the energy loss that meta causes.
When steering gear single movement, the leading role due to steering gear makes the valve port of flux amplification valve open, simultaneously the steering gear load-sensitive LS load-sensitive mouth of mouth pressure signal transmission to variable pump and the hydraulic control a hydraulic fluid port of pilot operated valve device; Now, for a point interflow selection function pilot operated valve device, variable pump carrys out the oily oil-in directly being entered flux amplification valve by the first pilot operated valve device and the 3rd one way valve, and the E hydraulic fluid port of point interflow selection function pilot operated valve device does not have fluid to pass through; Variable pump only carries out fuel feeding according to needed for steering load, avoids there is excess traffic and opens meta oil sump tank by banked direction control valves, decrease energy loss; Divide the hydraulic control a hydraulic fluid port of interflow selection function pilot operated valve device to be connected with load signal simultaneously, eliminate the valve precompensation function of the second pilot operated valve device completely, the hydraulic control a hydraulic fluid port avoiding point interflow selection function pilot operated valve device is subject to the effect of jitter of the second pilot operated valve device and cause turn to jitter problem by causing turning to oil circuit when ending, and keeps the stationarity turned to.
When the pilot valve single movement of banked direction control valves, hydraulic system of working load signal is communicated with variable pump, effect due to the b mouth pressure of the first pilot operated valve device makes the valve rod action of the first pilot operated valve device and is in left position, second pilot operated valve device is in right position because its hydraulic control end a hydraulic fluid port does not have pressure oil effect, but lead to the C hydraulic fluid port cut-off of flux amplification valve, variable pump carrys out the oily working oil entrance all being fed to banked direction control valves by fuel-displaced E hydraulic fluid port, realizes the interflow of work branch.
When the pilot valve of steering gear and banked direction control valves all has action, variable pump comes oily elder generation and is supplied to flux amplification valve and steering cylinder as required, simultaneously according to turning to the contrast situation with workload signal, fuel feeding is carried out to banked direction control valves as required by fuel-displaced E mouth, avoid excess traffic loss in work and steering procedure, and ensure that steering load signal is communicated with the hydraulic control a mouth of pilot operated valve device all the time, keep the stationarity turned to.When variable pump 2 reaches the cut-out pressure of setting, variable pump 2 keeps high-pressure low-flow fuel feeding, decreases energy loss.
The present invention compared with prior art, function of the present invention and advantage:
When a, loader attonity, make steering pump be in low-pressure low flow state, fuel feeding hardly, save energy consumption;
In b, separately steering procedure, steering pump, according to steering load fuel feeding as required, reduces restriction loss and middle bit-loss;
C, work independently in process, steering pump can realize the interflow function of steering pump fluid according to work pilot control;
D, when working and turn to simultaneously action, steering pump is except according to steering hydraulic system demand fuel feeding as required, and unnecessary flow is supplied to hydraulic system of working;
E, when steering hydraulic system pressure or hydraulic system of working pressure reach the cut-out pressure of steering pump, realize Isobarically Control;
F, realization determine on the basis of variable delivery hydraulic system, recover the function that traditional load sensitive sensor turns to, solution turn to jitter problem;
G, the problem solving engine idle hard steering or turn to the number of turns too much.
Accompanying drawing explanation
Fig. 1 is that the present invention divides interflow selection function pilot operated valve device hydraulic principle schematic diagram;
Fig. 2 is the hydraulic principle schematic diagram that knuckle section in variable delivery hydraulic system determined by loader of the present invention.
In figure: fuel tank 1, variable pump 2, point interflow selection function pilot operated valve device 3, first pilot operated valve device 31, second pilot operated valve device 32, first one way valve 35, second one way valve 37 and the 3rd one way valve 38, first segment discharge orifice 33, second section discharge orifice 34, the 3rd throttle orifice 36, shuttle valve 4, steering gear 5, flux amplification valve 6, steering cylinder 7.
Detailed description of the invention
Below in conjunction with accompanying drawing, specific embodiments is described.
One as shown in Figure 1 divides interflow selection function pilot operated valve device 3, comprise it and comprise the first pilot operated valve device 31, second pilot operated valve device 32, first one way valve 35, second one way valve 37, the 3rd one way valve 38, first segment discharge orifice 33, second section discharge orifice 34, the 3rd throttle orifice 36 and P hydraulic fluid port, b hydraulic fluid port, T hydraulic fluid port, a hydraulic fluid port, C hydraulic fluid port, E hydraulic fluid port, P hydraulic fluid port is communicated in the oil-in of the first pilot operated valve device 31, b hydraulic fluid port and T hydraulic fluid port are communicated in the left and right hydraulic control end of the first pilot operated valve device 31 respectively, the right hydraulic control end of the first pilot operated valve device 31 is spring cavity, and the T hydraulic fluid port be communicated with this spring cavity is oil return opening.The left hydraulic control end of the second pilot operated valve device 32 is spring cavity, and this chamber is communicated with a hydraulic fluid port.
When first pilot operated valve device 31 is in right position, its oil-in is through the 3rd one way valve 38 to C hydraulic fluid port one-way conduction, and when the first pilot operated valve device 31 is in left position, its oil-in is communicated in the oil-in of the second pilot operated valve device 32; A hydraulic fluid port is communicated in the left hydraulic control end of the second pilot operated valve device 32 through first segment discharge orifice 33, the left hydraulic control end of the second pilot operated valve device 32 is communicated in the entrance of the first one way valve 35 through the 3rd throttle orifice 36 through second section discharge orifice 34, right hydraulic control end, the outlet of the first one way valve 35 is in C hydraulic fluid port, when second pilot operated valve device 32 is in left position its oil-in through the first one way valve 35 to C hydraulic fluid port one-way conduction, when the second pilot operated valve device 32 is in right position its oil-in through the first one way valve 35 to C hydraulic fluid port one-way conduction and through the second one way valve 37 to E hydraulic fluid port one-way conduction.
Loader determines knuckle section in variable delivery hydraulic system as shown in Figure 2.Loader shown in Fig. 2 knuckle section determined in variable delivery hydraulic system comprises fuel tank 1, variable pump 2, steering gear 5, flux amplification valve 6, steering cylinder 7, shuttle valve 4 and above-mentioned point interflow selection function pilot operated valve device 3.The pilot pressure oil sources of pressure oil as steering gear 5 is introduced in steering gear 5 from flux amplification valve 6, and control output end is communicated in the corresponding hydraulic fluid port of flux amplification valve 6 thus the relevant action of control steering cylinder 7.The a hydraulic fluid port of interflow selection function pilot operated valve device 3 is divided to be communicated in the LS feedback port of steering gear 5, what C hydraulic fluid port was communicated in flux amplification valve 6 turns to oil-in, E hydraulic fluid port is communicated in the working oil entrance of banked direction control valves, and P hydraulic fluid port is communicated in the oil-out of variable pump 2, and b hydraulic fluid port is communicated in banked direction control valves pilot control oil circuit.The LS feedback port of steering gear 5 is communicated in an entrance of shuttle valve 4, and the outlet of shuttle valve 4 is in the load-sensitive mouth of variable pump 2.In Fig. 2, loader is determined unshowned working hydraulic pressure part in variable delivery hydraulic system and is comprised constant displacement pump, banked direction control valves, rotary ink tank and boom cylinder, pilot valve etc., constant displacement pump is by boom cylinder, the rotary ink tank fuel feeding of banked direction control valves to loader, banked direction control valves controls by pilot valve, and the load feedback oil circuit of banked direction control valves is communicated in the another one entrance of shuttle valve 4.
In the present embodiment, when the equal attonity of the pilot valve of steering gear 5 and banked direction control valves, because point fuel-displaced C hydraulic fluid port of interflow selection function pilot operated valve device 3 and fuel-displaced E hydraulic fluid port are all cut off, the load-sensitive mouth no signal of variable pump 2, variable pump 2 not fuel feeding, avoids banked direction control valves and opens the energy loss that meta causes.
When steering gear 5 single movement, leading role due to steering gear 5 makes the valve port of flux amplification valve 6 open, the load-sensitive mouth of the load-sensitive of steering gear 5 simultaneously LS mouth pressure signal transmission to variable pump 2 and a hydraulic fluid port of point interflow selection function pilot operated valve device 3, now, for a point interflow selection function pilot operated valve device 3, the second pilot operated valve device 32 is made to be in left position, first pilot operated valve device 31 is in right position, the oily oil-in directly being entered flux amplification valve 6 by the first pilot operated valve device 31 and the 3rd one way valve 38 through C hydraulic fluid port of variable pump 2, the E hydraulic fluid port of interflow selection function pilot operated valve device 3 is divided not have fluid to pass through, variable pump 2 only carries out fuel feeding according to needed for steering load, avoids there is excess traffic and opens meta oil sump tank by banked direction control valves, decrease energy loss, divide the hydraulic control a hydraulic fluid port of interflow selection function pilot operated valve device 3 to be connected with load signal simultaneously, eliminate the valve precompensation function of the second pilot operated valve device 32 completely, the hydraulic control a hydraulic fluid port avoiding point interflow selection function pilot operated valve device 3 is subject to the effect of jitter of the second control valve and cause turn to jitter problem by causing turning to oil circuit when ending, and keeps the stationarity turned to.
When the pilot valve single movement of banked direction control valves, hydraulic system of working load signal is communicated with variable pump, effect due to the b hydraulic fluid port pressure of the first pilot operated valve device 31 makes the valve rod action of the first control valve 31 and is in left position, second pilot operated valve device 32 is in right position because its hydraulic control end a hydraulic fluid port does not have pressure oil effect, but lead to the C hydraulic fluid port cut-off of flux amplification valve, the oily working oil entrance all being fed to banked direction control valves by fuel-displaced E hydraulic fluid port of variable pump 2, realizes the interflow of work branch.
When the pilot valve of steering gear 5 and banked direction control valves all has action, variable pump comes oily elder generation and is supplied to flux amplification valve and steering cylinder as required, simultaneously according to turning to the contrast situation with workload signal, fuel feeding is carried out to banked direction control valves as required by fuel-displaced E mouth, avoid excess traffic loss in work and steering procedure, and ensure that steering load signal is communicated with the hydraulic control a mouth of pilot operated valve device all the time, keep the stationarity turned to.When variable pump 2 reaches the cut-out pressure of setting, variable pump 2 keeps high-pressure low-flow fuel feeding, decreases energy loss.
Claims (4)
1. one kind of point of interflow selection function pilot operated valve device, it is characterized in that comprising the first pilot operated valve device (31), second pilot operated valve device (32), first one way valve (35), second one way valve (37) and the 3rd one way valve (38), first segment discharge orifice (33), second section discharge orifice (34), 3rd throttle orifice (36) and P hydraulic fluid port, b hydraulic fluid port, T hydraulic fluid port, a hydraulic fluid port, C hydraulic fluid port, E hydraulic fluid port, described P hydraulic fluid port is communicated in the oil-in of described first pilot operated valve device, described b hydraulic fluid port and T hydraulic fluid port are communicated in the left and right hydraulic control end of described first pilot operated valve device respectively, when described first pilot operated valve device is in right position its oil-in through the 3rd one way valve to C hydraulic fluid port one-way conduction, when described first pilot operated valve device is in left position, its oil-in is communicated in the oil-in of described second pilot operated valve device, described a hydraulic fluid port is communicated in the left hydraulic control end of described second pilot operated valve device through first segment discharge orifice, the left hydraulic control end of described second pilot operated valve device is communicated in the entrance of described first one way valve through the 3rd throttle orifice through second section discharge orifice, right hydraulic control end, the outlet of described first one way valve is in described C hydraulic fluid port, when described second pilot operated valve device is in left position its oil-in through the first one way valve to the conducting of C hydraulic fluid port, when described second pilot operated valve device is in right position its oil-in through the first one way valve to C hydraulic fluid port one-way conduction and through the second one way valve to E hydraulic fluid port one-way conduction.
2. according to claim 1 point of interflow selection function pilot operated valve device, it is characterized in that the right hydraulic control end of described first pilot operated valve device is spring cavity, the T hydraulic fluid port be communicated with this spring cavity is oil return opening.
3. according to claim 1 point of interflow selection function pilot operated valve device, is characterized in that the left hydraulic control end of described second pilot operated valve device is spring cavity.
4. variable delivery hydraulic system determined by a loader, comprise variable pump (2), steering gear (5), flux amplification valve (6), banked direction control valves, characterized by further comprising point interflow selection function pilot operated valve device according to any one of claims 1 to 3, the a hydraulic fluid port of described point of interflow selection function pilot operated valve device is communicated in the LS feedback port of described steering gear, C hydraulic fluid port is communicated in the oil-in of described flux amplification valve, E hydraulic fluid port is communicated in the working oil entrance of described banked direction control valves, P hydraulic fluid port is communicated in the oil-out of described variable pump, b hydraulic fluid port is communicated in the pilot pressure oil circuit control of banked direction control valves.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410627890.9A CN104358286B (en) | 2014-11-10 | 2014-11-10 | Deciliter stream selects function pilot operated valve device and loader to determine variable delivery hydraulic system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410627890.9A CN104358286B (en) | 2014-11-10 | 2014-11-10 | Deciliter stream selects function pilot operated valve device and loader to determine variable delivery hydraulic system |
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| CN104358286A true CN104358286A (en) | 2015-02-18 |
| CN104358286B CN104358286B (en) | 2016-06-29 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201410627890.9A Active CN104358286B (en) | 2014-11-10 | 2014-11-10 | Deciliter stream selects function pilot operated valve device and loader to determine variable delivery hydraulic system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104929183A (en) * | 2015-05-21 | 2015-09-23 | 徐工集团工程机械股份有限公司科技分公司 | Loader constant and variable hydraulic system based on flow amplifying steering |
| CN105134678A (en) * | 2015-08-26 | 2015-12-09 | 徐工集团工程机械股份有限公司科技分公司 | Pilot control valve block, core opening and closing hydraulic system and engineering machine |
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| JP2003106305A (en) * | 2001-09-28 | 2003-04-09 | Kobelco Contstruction Machinery Ltd | Gyrating control circuit |
| CN201301466Y (en) * | 2008-11-13 | 2009-09-02 | 贵州詹阳动力重工有限公司 | Rotary oil supply loop for hydraulic excavator |
| CN102296664A (en) * | 2011-06-23 | 2011-12-28 | 徐州徐工挖掘机械有限公司 | Hydraulic driving device of excavator |
| CN102912823A (en) * | 2012-11-09 | 2013-02-06 | 浙江大学 | Rotary energy saving system of excavator |
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| DE10104298A1 (en) * | 2000-05-11 | 2001-11-15 | Mannesmann Rexroth Ag | Hydraulic control device for damping travel vibrations of mobile work apparatus involves hydro-cylinder supporting work tool, cylinder chambers of which are connectable via control valve arrangement with pressure medium source or tank |
| JP2003106305A (en) * | 2001-09-28 | 2003-04-09 | Kobelco Contstruction Machinery Ltd | Gyrating control circuit |
| CN201301466Y (en) * | 2008-11-13 | 2009-09-02 | 贵州詹阳动力重工有限公司 | Rotary oil supply loop for hydraulic excavator |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104929183A (en) * | 2015-05-21 | 2015-09-23 | 徐工集团工程机械股份有限公司科技分公司 | Loader constant and variable hydraulic system based on flow amplifying steering |
| CN105134678A (en) * | 2015-08-26 | 2015-12-09 | 徐工集团工程机械股份有限公司科技分公司 | Pilot control valve block, core opening and closing hydraulic system and engineering machine |
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| Publication number | Publication date |
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| CN104358286B (en) | 2016-06-29 |
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