CN106759621B - Load-sensitive formula loading machine determines variable delivery hydraulic system - Google Patents
Load-sensitive formula loading machine determines variable delivery hydraulic system Download PDFInfo
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- CN106759621B CN106759621B CN201710005638.8A CN201710005638A CN106759621B CN 106759621 B CN106759621 B CN 106759621B CN 201710005638 A CN201710005638 A CN 201710005638A CN 106759621 B CN106759621 B CN 106759621B
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
- E02F9/2221—Control of flow rate; Load sensing arrangements
- E02F9/2225—Control of flow rate; Load sensing arrangements using pressure-compensating valves
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Abstract
The present invention relates to loader hydraulic systems more particularly to a kind of load-sensitive formula loading machine to determine variable delivery hydraulic system, includes logic control valve and flow control valve；The EF hydraulic fluid port of the logic control valve connects multi-way valve by the hydraulic-control throttling valve of flow control valve, and pilot valve is separately connected the pilot operated directional control valve KL hydraulic fluid port of logic control valve and the hydraulic-control throttling valve LS8 hydraulic fluid port of flow control valve.The present invention adds three-way pressure compensating device in current quantitative work system and hydraulic-control throttling valve group is closed, it is adaptive by by-pass tee pressure compensator Low-pressure load discharge and constant displacement pump load pressure to realize work system, and then realizes and loads the unrelated flow of variation and precisely export；And realize variable pump full working scope and become discharge capacity, utmostly play variable pump advantage.
Description
Technical field
The present invention relates to engineering machinery more particularly to a kind of loading machine to determine variable delivery hydraulic system.
Background technique
Loading machine is that a kind of operating efficiency is high, widely used engineering machinery, and hydraulic system is mainly by working hydraulic pressure system
System and steering hydraulic system composition.Domestic existing loader hydraulic system has full fixed dilivery hydraulic system, entire variable hydraulic system, determines
Variable delivery hydraulic system etc..The system that wherein full fixed dilivery hydraulic system, i.e. steering system and work system are all made of constant displacement pump, at
This is lower, but belongs to out middle position overflowing and speed system, and there are spill losses, restriction loss, middle bit-loss, therefore the hydraulic systems
Energy consumption is high, fever is big, efficiency is relatively low；Entire variable hydraulic system is closed using double load-reacting plunger pumps, load-sensitive
The Hydraulic Elements such as middle level control valve, relative quantification hydraulic system operation comfort will be got well, and be able to achieve power control and energy conservation, but main
Wanting problem is higher cost, very sensitive to system clean degree, small pollution will performance to product, quality, use the longevity
Life and reliability, that is, time between failures generation seriously affect；Determine variable delivery hydraulic system, i.e. steering system uses load-sensitive
Variable plunger pump, work system uses constant displacement pump, with regard to its cost and energy-saving effect comprehensive assessment, determine variable delivery hydraulic system with compared with
High cost performance, principle are simply easily achieved, but present is determined variable delivery hydraulic system and had the following problems in use:
(1) when complete machine equipment acts, the existing Variable plunger pump for determining variable system becomes constant pressure variable displacement pump interflow
To hydraulic system of working, i.e., on not up to variable pump before pressure regulator valve setting pressure, variable pump swash plate is in sail angle, pump
Discharge capacity maximum and displacement constant, actually this suitable constant displacement pump of stage constant pressure variable displacement pump.And then equipment is micro- at interflow
Control and there are high pressure restriction losses and spill losses variable pump advantage not to play to greatest extent when in maximum pressure.Such as Fig. 5
With shown in Fig. 6, the load of variable pump is quick in CN104405006A and CN104929183A technical solution disclosed in Parker and Xu work
Sense signal LS/X is derived from oil inlet P/A of multi-way valve, and when work system work, the load-sensitive valve both ends pressure difference of variable pump is low
In setting value, variable pump swash plate is in sail angle, is exported with maximum pump discharge, and interflow to work system loses become discharge capacity at this time
Function.
(2) existing to determine in variable system, paced work system is widely used out center six and leads to multi-way valve, and speed regulation is using side
The combination of road throttling and meter in, speed regulation effect is throttled by valve rod, and control goes the amount of opening of oil cylinder and oil return box
It realizes.Due to being that the pressure of meter out foundation is leaned on to overcome load pressure, governor control characteristics is by load pressure and oil pump
The influence of flow.When spool stroke is certain, load pressure increases, and the flow of oil cylinder is gone to be reduced by.Whole working load pressure
Power be it is unstable vary, the flow of hydraulic pump is also constantly changing, thus adjust the speed it maneuvering performance is very unstable, and manipulation is tired
It is difficult；And valve rod steering force is big, and since load pressure variation causes valve port △ P to change, hydraulic power variation causes valve rod steering force
Change, the scrambling of steering force, keeps fine tuning control more difficult.In short, the oil circuit poor controllability, operator will accurately control
Equipment be it is highly difficult, feel entirely by operator, experience and performance.
(3) for the existing constant displacement pump for determining variable system when work system does not work, flow can be by holding middle position multi-way valve
Fuel tank is flowed back to, biggish middle position linear loss is generated, so hydraulic system is caused to generate very big heat, energy consumption is big.
Summary of the invention
In view of the above-mentioned problems, it is an object of the invention to propose a kind of more energy saving, handling it is good, compared with high performance-price ratio
Load-sensitive formula loading machine determine variable delivery hydraulic system.
What the present invention was implemented with the following technical solutions: a kind of load-sensitive formula loading machine determines variable delivery hydraulic system, including
There are variable pump, constant displacement pump, fuel tank, flow control valve, pilot valve, boom cylinder and rotary ink tank, multi-way valve, shuttle valve block, flow
Amplify valve block, diverter, logic control valve；Variable pump connects flux amplification valve block, logic by the CF hydraulic fluid port of logic control valve
The T1 oil return opening of control valve is connected to fuel tank, and constant displacement pump connects multi-way valve by flow control valve, multi-way valve connect rotary ink tank with
The EF hydraulic fluid port of boom cylinder, the logic control valve connects multi-way valve by the hydraulic-control throttling valve of flow control valve, and pilot valve is logical
It crosses shuttle valve block and is separately connected the pilot operated directional control valve KL hydraulic fluid port of logic control valve and the hydraulic-control throttling valve LS8 hydraulic fluid port of flow control valve；
When the signal pressure that shuttle valve block LS6 passes to the hydraulic-control throttling valve LS8 hydraulic fluid port of flow control valve is low, pressure difference before and after hydraulic-control throttling valve
When pressure-compensated valve higher than logic control valve closes setting pressure, variable pump oil liquid is not to flow control valve interflow only for turning to
System, flow needed for constant displacement pump exports rotary ink tank and boom cylinder according to the hydraulic-control throttling valve opening of flow control valve are extra
Flow oil return box；When the signal pressure that shuttle valve block LS6 hydraulic fluid port passes to hydraulic-control throttling valve LS8 hydraulic fluid port is high, and rotary ink tank and dynamic
Flow needed for flow needed for arm oil cylinder is greater than constant displacement pump, hydraulic-control throttling valve front and back pressure difference are lower than the pressure-compensated valve of logic control valve
When closing setting pressure, variable pump collaborates to flow control valve to multi-way valve, provides shortcoming flow.
The flow control valve includes three-way pressure compensating device, damping hole, check valve, hydraulic-control throttling valve, pressure control
Valve, unloading valve and P6 hydraulic fluid port, P7 hydraulic fluid port, P8 hydraulic fluid port, LS7 hydraulic fluid port, LS8 hydraulic fluid port, T4 hydraulic fluid port；Three-way pressure compensating device into
Mouthful it is connected with P6 mouthfuls, the import of unloading valve, check valve, the outlet of three-way pressure compensating device and off-load valve outlet, pressure-control valve
Outlet is connect after connecting with T4 mouthfuls；One-way valved outlet is connected in P8 hydraulic fluid port, the import of hydraulic-control throttling valve and pressure-control valve
Pressure control mouth；The spring cavity of unloading valve is connected in the import of pressure-control valve；P6 hydraulic fluid port connects constant displacement pump, and the connection of P7 hydraulic fluid port is more
Road valve, P8 hydraulic fluid port are connect with the EF hydraulic fluid port of logic control valve, and LS7 hydraulic fluid port connects logic control valve LS3 hydraulic fluid port and transmits work and bears
Information carrying number, LS8 hydraulic fluid port are connect with shuttle valve block LS6 hydraulic fluid port；Pressure difference between the P7 hydraulic fluid port of hydraulic-control throttling valve, P8 hydraulic fluid port is by threeway pressure
The setting of force compensating device, the hydraulic-control throttling valve opening is adjusted according to the pilot signal that shuttle valve block transmits, needed for output services system
Flow.
The logic control valve includes fixed pressure reducing valve, pilot operated directional control valve, flow compensation valve, pressure-compensated valve, shuttle
Valve, check valve and P1 hydraulic fluid port, PX hydraulic fluid port, PSt hydraulic fluid port, LS1 hydraulic fluid port, LS2 hydraulic fluid port, LS3 hydraulic fluid port, KL hydraulic fluid port, CF hydraulic fluid port, EF
Hydraulic fluid port, T1 hydraulic fluid port；The P1 hydraulic fluid port is connected to CF hydraulic fluid port, and P1 hydraulic fluid port connects PX hydraulic fluid port, another way warp by fixed pressure reducing valve all the way
Check valve connects PSt hydraulic fluid port, connects flow compensation valve spring cavity by pilot operated directional control valve, passes through flow compensation valve, pressure compensation
Valve connects EF hydraulic fluid port；The LS2 hydraulic fluid port and the LS3 hydraulic fluid port select to be connected to the LS1 hydraulic fluid port through shuttle valve；The KL hydraulic fluid port
It is connected to pilot operated directional control valve control terminal；The spring cavity of the fixed pressure reducing valve and pilot operated directional control valve is connected to T1 hydraulic fluid port；The LS3 oil
Mouth is connected to pressure-compensated valve spring cavity；CF hydraulic fluid port preferential attachment Flow amplification valve block, P1 hydraulic fluid port link variable pump, T1 hydraulic fluid port connect
Connected tank, KL hydraulic fluid port are derived from the signal of shuttle valve block, and EF hydraulic fluid port connects flow control valve, and LS3 is derived from flow control valve load feedback
Mouthful, PX hydraulic fluid port connects diverter, and PSt hydraulic fluid port connects pilot valve；Pressure difference between EF hydraulic fluid port and LS3 hydraulic fluid port determines pressure-compensated valve
Aperture, control steering system whether to work system collaborate and collaborate flow.
The shuttle valve block include the first shuttle valve, the second shuttle valve, third shuttle valve, two-way pilot operated valve device and D1 hydraulic fluid port, D2 hydraulic fluid port,
C1 hydraulic fluid port, C2 hydraulic fluid port, LS5 hydraulic fluid port, LS6 hydraulic fluid port, D1 hydraulic fluid port, D2 hydraulic fluid port are connected to after the first shuttle valve gating by two-way pilot operated valve device
Third shuttle valve left end, C1 hydraulic fluid port, C2 hydraulic fluid port are connected to third shuttle valve right end, third shuttle valve outlet after the second shuttle valve gating
LS5 hydraulic fluid port, LS6 hydraulic fluid port；Two-way pilot operated valve device control terminal and the second shuttle valve outlet；The KL of LS5 hydraulic fluid port connection logic control valve
Hydraulic fluid port, LS6 hydraulic fluid port connect the LS8 hydraulic fluid port of flow control valve；D1 hydraulic fluid port, D2 hydraulic fluid port, C1 hydraulic fluid port, the connection pilot valve control of C2 hydraulic fluid port
Mouthful.
C1 hydraulic fluid port, the C2 hydraulic fluid port of the shuttle valve block are separately connected pilot valve rotating bucket control mouth A, rotating bucket control mouth C, D1 oil
Mouth, D2 hydraulic fluid port are separately connected pilot valve swing arm control mouth B, swing arm control mouth D, C1 hydraulic fluid port/C2 hydraulic fluid port fuel injection pressure signal and push two-way
Pilot operated valve device is in bottom, makes D1 hydraulic fluid port/D2 hydraulic fluid port signal-off.
The logic control valve further includes having safety valve, and safety valve connects P1 hydraulic fluid port and T1 hydraulic fluid port.
The steering system includes Flow amplification valve block.
Three-way pressure compensating device of the invention can be applied in constant displacement pump pressure compensating system.The pressure compensator is applied
In hydraulic system with constant displacement pump, and cooperate with throttle valve, not only solves automatic pressure compensation, proof load passes through throttling when changing
The flow of valve is basicly stable, and the outlet pressure of pump can be made to match always with load, realizes energy conservation, successively makes entire
The power of hydraulic system declines.The present invention determines variable delivery hydraulic system using load-sensitive formula loading machine, in current quantitative job family
Three-way pressure compensating device and hydraulic-control throttling valve group is added in system to close so that current quantitative pump open middle position overflowing and speed system upgrade at
Constant displacement pump load sensitive system realizes work system and passes through by-pass tee pressure compensator Low-pressure load discharge and quantitative pump load pressure
Force adaptive, and then realize that the flow unrelated with load variation precisely exports；Another technical solution of the present invention is also closed in variable pump
Pressure-compensated valve, and opening and closing and the liquid of the pressure-compensated valve and variable pump load-sensitive valve are added in diverter module logic control valve
Pressure difference is associated with before and after controlling throttle valve, is realized variable pump full working scope and is become discharge capacity, utmostly plays variable pump advantage.With existing skill
Art is compared and is had the advantages that
(1) in constant displacement pump pressure compensating system, when multi-way valve is in middle position and does not work, by three-way pressure compensating device to pump
Realize off-load, to pump up decompression and protective effect.Three-way pressure compensating device pressure unloading is small simultaneously, when realization system does not work
Energy conservation.
(2) when the system is operating, multi-way valve import and outlet pressure are poor when three-way pressure compensating device ensure that load variation
It is constant, system is realized precisely to be exported with the unrelated flow of load variation, that is, flows through the size and spool of multi-way valve flow
Be displaced it is related, it is unrelated with load variations；It can not only realize that the load of the flow controller front and back constant i.e. pressure compensator of pressure difference is mended very well
The effect of repaying, and it is poor that the outlet of pump can be made only than load pressure to be higher by a level pressure in real time, to realize that load pressure is adaptive
It answers.
(3) it is closed in diverter module logic control valve in variable pump and adds pressure-compensated valve, and the pressure-compensated valve and variable
The opening and closing of pump load sensitive valve is associated with pressure difference before and after hydraulic-control throttling valve, is realized variable pump full working scope and is become discharge capacity, utmostly
Play variable pump advantage.
Detailed description of the invention
Fig. 1 is systematic schematic diagram of the embodiment of the present invention；
Fig. 2 is the schematic diagram of logic control valve in the embodiment of the present invention；
Fig. 3 is the schematic diagram of shuttle valve block in the embodiment of the present invention；
Fig. 4 is the schematic diagram of flow control valve in the embodiment of the present invention；
Fig. 5 is system diagram disclosed in CN104405006A；
Fig. 6 is system diagram disclosed in CN104929183A；
Description of symbols in figure:
1- variable pump, 2- constant displacement pump, 3- filter, 4- fuel tank, 5- flow control valve, 6- accumulator, 7- pilot valve, 8- are dynamic
Arm oil cylinder, 9- rotary ink tank, 10- multi-way valve, 11- shuttle valve block, 12- steering cylinder, 13- Flow amplification valve block, 14- diverter,
15- logic control valve, 16- fixed pressure reducing valve, 17- pilot operated directional control valve, 18- flow compensation valve, 19- safety valve, 20- damping hole,
21- pressure-compensated valve, 22- damping hole, 23- shuttle valve, 24- damping hole, 25- check valve, 26- three-way pressure compensating device, 27- damping
Hole, 28- check valve, 29- hydraulic-control throttling valve, 30- pressure-control valve, 31- unloading valve, the first shuttle valve of 32-, 33- two-way pilot operated valve device,
The second shuttle valve of 34-, 35- third shuttle valve.
Specific embodiment
To further understand the present invention, technical solution of the present invention is done into one with reference to the accompanying drawings and detailed description
Step explanation, referring to Fig. 1 to Fig. 4:
As shown in Figure 1, hydraulic system in the present embodiment, including variable pump 1, constant displacement pump 2, filter 3, fuel tank 4, flow control
Valve 5 processed, accumulator 6, pilot valve 7, boom cylinder 8, rotary ink tank 9, multi-way valve 10, shuttle valve block 11, steering cylinder 12, flow are put
The compositions such as big valve block 13, diverter 14, logic control valve 15.The inlet port of variable pump 1 is connected with hydraulic oil container 4；Variable pump 1
Oil outlet is connected with the P1 of logic control valve 15 mouth；The LS4 mouth phase of the LS2 mouth of logic control valve 15 and Flow amplification valve block 13
Even；The CF mouth of logic control valve 15 is connected with the P2 of Flow amplification valve block 13 mouth；The KL mouth and shuttle valve block 11 of logic control valve 15
LS5 mouth be connected；The LS3 mouth of logic control valve 15 is connected with the LS7 of flow control valve 5 mouth；The EF mouth of logic control valve 15 with
The P8 of flow control valve 5 is connected；The T1 mouth of logic control valve 15 and the T2 mouth of diverter 14, the T3 of Flow amplification valve block 13
Mouth, the T4 mouth of flow control valve 5, multi-way valve 10 T5 mouth be connected after be connected again with filter 3, be finally connected with fuel tank 4；Logic
The Px mouth of control valve 15 is connected with the P4 of diverter 14 mouth；The P5 mouth of the Pst mouth of logic control valve 15 and accumulator 6, pilot valve 7
It is connected；The LS1 mouth of logic control valve 15 is connected with the LS of variable pump 1 mouth；The A/B mouth and steering cylinder 12 of Flow amplification valve block 13
Corresponding chambers be connected.The a of the L mouth Flow amplification valve block 13 of diverter 14 is connected；The R mouth and Flow amplification valve block of diverter 10
13 b is connected；The C mouth of pilot valve 7 is connected with the C2 mouth of the b1 of multi-way valve 10 mouth, shuttle valve block 11；The A mouth and multichannel of pilot valve 7
The a1 mouth of valve 10, the C1 mouth of shuttle valve block 11 are connected；The B mouth of pilot valve 7 and the a2 mouth of multi-way valve 10, the D1 mouth phase of shuttle valve block 11
Even；The D mouth of pilot valve 7 is connected with the D2 mouth of the b2 of multi-way valve 10 mouth, shuttle valve block 11；A1 mouth and the rotating bucket cylinder 9 of multi-way valve 10
Rodless cavity is connected；The B1 mouth of multi-way valve 10 is connected with the rod chamber of rotating bucket cylinder 9；The A2 mouth of multi-way valve 10 is with swing arm cylinder 8 without bar
Chamber is connected；The B2 mouth of multi-way valve 10 is connected with the rod chamber of swing arm cylinder 8；The LS8 of the LS6 mouth and flow control valve 5 of shuttle valve block 11
Hydraulic fluid port is connected；The inlet port of constant displacement pump 2 is connected with fuel tank 4；The oil outlet of constant displacement pump 2 is connected with the P6 of flow control valve 5 mouth；Stream
The P7 mouth of control valve 5 is connected with the P3 of multi-way valve 10 mouth.
In the present embodiment, as shown in Fig. 2, logic control valve includes fixed pressure reducing valve 16, pilot operated directional control valve 17, flow benefit
Repay valve 18, safety valve 19, damping hole 20, pressure-compensated valve 21, damping hole 22, shuttle valve 23, damping hole 24, check valve 25 and P1
The groups such as hydraulic fluid port, LS2 hydraulic fluid port, CF hydraulic fluid port, KL hydraulic fluid port, LS3 hydraulic fluid port, EF hydraulic fluid port, T1 hydraulic fluid port, PX hydraulic fluid port, PSt hydraulic fluid port, LS1 hydraulic fluid port
At.The P1 hydraulic fluid port is connected in fixed pressure reducing valve 16, the oil inlet of flow compensation valve 18, and is connected at pilot operated directional control valve 17
Oil inlet at bottom；The LS2 hydraulic fluid port connects the oil inlet when left end of shuttle valve 23 and pilot operated directional control valve 17 are in upper
Mouthful；The LS3 hydraulic fluid port is connected through damping hole 20 in 21 spring cavity of pressure-compensated valve, and is connected with 23 right end of shuttle valve；Shuttle valve 23 goes out
Hydraulic fluid port is connected through damping hole 24 in LS1 hydraulic fluid port；Fixed pressure reducing valve 16 is connected in 25 oil inlet of check valve and PX hydraulic fluid port, check valve 25
Oil outlet and PSt hydraulic fluid port connect；The liquid controling cavity and KL hydraulic fluid port of pilot operated directional control valve 17 are connected, and oil outlet is through damping hole 22 and flow
The spring cavity of recuperation valve 18 is connected；The oil outlet of flow compensation valve 18 is connected in the oil inlet of pressure-compensated valve 21, pressure compensation
The oil outlet and EF hydraulic fluid port of valve 21 are connected；19 oil inlet of safety valve and P1 hydraulic fluid port and CF hydraulic fluid port are connected, and oil outlet connects through T1 hydraulic fluid port
Oil return box 4.
In the present embodiment, as shown in figure 4, flow control valve includes three-way pressure compensating device 26, damping hole 27, check valve
28, hydraulic-control throttling valve 29, pressure-control valve 30, unloading valve 31 and P6 hydraulic fluid port, LS7 hydraulic fluid port, LS8 hydraulic fluid port, P7 hydraulic fluid port, T4 oil
The composition such as mouth.The oil inlet of three-way pressure compensating device 26 with P6 mouthfuls, unloading valve 31, check valve 28 oil inlet be connected, threeway pressure
The oil outlet of force compensating device 26 is connect after connecting with 31 oil outlet of unloading valve, 30 oil outlet of pressure-control valve with T4 mouthfuls；Check valve
28 oil outlets are connected in the pressure control port of P8 hydraulic fluid port, the oil inlet of three-way pressure compensating device 26 and pressure-control valve 30；
The spring cavity of unloading valve 31 is connected in the oil inlet of pressure-control valve 306.The oil outlet P7 and multichannel of three-way pressure compensating device 26
The import P3 connection of valve 10.
The operation principle of the present invention is that:
1, when without steering, without work.Diverter 14 does not work, then the LS4 oil duct of Flow amplification valve block 13 and oil return T3 phase
Logical, the LS pressure of feedback to variable pump 1 is 0.Pilot valve 7 does not work, and pilot valve output pressure is 0, at each spool of multi-way valve 10
Yu Zhongwei, valve port are closed, the 2/2-way valve 33 in shuttle valve block 11 be in it is upper in figure, because oil-collecting hole C1, C2, D1, D2 are equal
No pilot pressure input, so load signal LS5, LS6 output pressure of shuttle valve block 11 is zero, so in flow control valve 5
Hydraulic-control throttling valve 29 is in right position in figure, and valve port is in close state, and the pilot operated directional control valve 17 in logic control valve 15 is in just
The next in the beginning location drawing, 18 spring cavity of flow compensation valve and ante-chamber are all communicated with the hydraulic fluid port that pumps out of load-reacting pump, the valve
Core will always be in closed state, collaborate obstructed to the oil circuit of work system.Hydraulic-control throttling valve 29 in flow control valve 5 goes out
Mouth pressure is 0, and the three-way pressure compensating device 26 in flow control valve 5 is in open state, and the oil of constant displacement pump 2 is through three-way pressure
26 off-load oil return box of compensator；Load-sensitive valve spring cavity pressure in variable pump 1 is 0, and Ioad-sensing control valve is in figure
Left position, variable pump swash plate angle are minimum swash angle, and output flow 0,1 output pressure of variable pump is its Ioad-sensing control valve
Pressure differential resetting value, variable pump 1 are in stand-by operation state.
Work system does not work, when steering system works.
Pilot valve 7 does not work, and pilot valve output pressure is 0, and each spool of multi-way valve 10 is in middle position, and valve port is closed, shuttle valve
2/2-way valve 33 in block 11 be in it is upper in figure, because oil-collecting hole C1, C2, D1, D2 without pilot pressure input, so shuttle
Load signal LS5, LS6 output pressure of valve block 11 is 0, so the hydraulic-control throttling valve 29 in flow control valve 5 is in figure right
Position, valve port are in close state, and the pilot operated directional control valve 17 in logic control valve 15 is in initial position figure the next, flow-compensated
18 spring cavity of valve and ante-chamber are all communicated with P1 hydraulic fluid port, which will always be in closed state, are collaborated to the oil circuit of work system
It is obstructed.Enter diverter after the fixed pressure reducing valve 16 that rotation diverter 14, the oil liquid of variable pump 1 pass through logic control valve 15
14,14 pressure output control of diverter pushes 13 valve core movement of Flow amplification valve block, and 1 output flow of variable pump is through Flow amplification
Valve block 13 enters steering cylinder 12, turns to work.The load pressure of steering cylinder 12 is fed back by LS4 oil circuit to flux amplification valve
The LS mouth of the fixed poor flow valve spring cavity and variable pump 1 of block 13, keeps 1 output pressure of variable pump only one higher than steering load pressure
Pressure set points, variable pump 1 automatically adjust swash plate angle, flow needed for only output is corresponding with diverter revolving speed.Due to flow control
The outlet pressure of hydraulic-control throttling valve 29 in valve 5 processed is 0, and the three-way pressure compensating device 26 in flow control valve 5 is in open
State, therefore the oil of constant displacement pump 2 is through 26 off-load oil return box 4 of three-way pressure compensating device.
Steering system does not work, when work system works
(1) boom arm lift acts.2/2-way valve 33 in manipulation pilot valve 7 to boom arm lift position, shuttle valve block 11
It works upper in figure, the boom arm lift pilot pressure of pilot valve 7 is through shuttle valve 32, the 2/2-way valve 33, shuttle in shuttle valve block 11
Valve 35 passes to the hydraulic-control throttling valve 29 in flow control valve 5 and 17 liquid controling cavity of pilot operated directional control valve in logic control valve 15 respectively,
It when pilot pressure reaches a certain setting value, pushes 17 spool of pilot operated directional control valve to commutate into figure upper, keeps steering LS2 pressure anti-
It is fed to 18 spring cavity of flow compensation valve, the oil liquid pressure of variable pump 1 acts on 18 spool epicoele of flow compensation valve, flow compensation valve
18 open.
When 7 output pressure of pilot valve is lower, the hydraulic-control throttling valve 29 in flow control valve 5 is in small open-work, when
When pressure difference is greater than a certain setting value before and after the valve of hydraulic-control throttling valve 29,21 valve port of pressure-compensated valve in logic control valve 15 subtracts
Small, until closing, the not output flow of variable pump 1, variable pump 1, which does not conform to, at this time flow to work system.Simultaneously in flow control valve 5
26 both ends pressure difference of three-way pressure compensating device is more than spring setting value, and spool moves downward, and makes three-way pressure compensating device 23 and oil return
The aperture in road increases, and flow needed for 2 output services device of constant displacement pump enters raise-position on 10 swing arm of multi-way valve, and excess traffic is through three
Lead to the direct off-load of pressure compensator 23 to fuel tank 4.
When the output pressure of pilot valve 7 increases, the valve port of the hydraulic-control throttling valve 29 in flow control valve 5 increases, hydraulic control section
Pressure difference reduces before and after flowing the valve of valve 29, and the three-way pressure compensating device 26 in flow control valve 5 is turned down with drainback passage, when pressure difference is small
After spring setting value, three-way pressure compensating device 26 and drainback passage are closed, and 2 flow of constant displacement pump all flow to work system.Together
When reduce with the pressure difference of multi-way valve inlet pressure and load pressure, 21 valve port of pressure-compensated valve in logic control valve 15 is slow
Increasing, while load pressure reaches the LS mouth in variable pump 1 through shuttle valve 23, variable pump 1 exports oil liquid and enters hydraulic system of working,
Flow needed for supplementing work system realizes Dual-pump flow-converging, and 1 output flow size of variable pump depends in logic control valve 15 at this time
21 valve port opening of pressure-compensated valve.
(2) swing arm lowering action.Circuit theory is no longer described with " boom arm lift movement ".
(3) swing arm floating acts.Circuit theory is no longer described with " boom arm lift movement ".
(4) when steering system and work system work at the same time by taking boom arm lift acts as an example.When steering hydraulic system work,
When hydraulic system of working boom arm lift, the LS4 mouth of Flow amplification valve block 13 has load pressure signal, and pilot valve 7 also has pressure letter
Number, the LS4 signal of Flow amplification valve block 13 is transmitted to the left end interface of the shuttle valve 23 in logic control valve 15.Pilot valve 7 moves
Arm promotes pilot pressure and is passed in flow control valve 5 respectively through shuttle valve 32,2/2-way valve 33, the shuttle valve 35 in shuttle valve block 11
17 liquid controling cavity of pilot operated directional control valve in hydraulic-control throttling valve 29 and logic control valve 15, when pilot pressure reaches a certain setting value,
It pushes 17 spool of pilot operated directional control valve to commutate into figure upper, makes to turn to LS2 pressure feedback to 18 spring cavity of flow compensation valve, variable
The oil liquid pressure of pump 1 acts on 18 spool epicoele of flow compensation valve.The outlet pressure of hydraulic-control throttling valve 29 in flow control valve 5
26 spring cavity of three-way pressure compensating device in flow control valve 5,21 bullet of pressure-compensated valve in logic control valve 15 are passed to respectively
The right end interface of spring chamber and shuttle valve 23.2 oil liquid of constant displacement pump gives the upper raise-position fuel feeding of 10 swing arm of multi-way valve through flow control valve 5, more
Residual current amount is through 26 off-load oil return box of three-way pressure compensating device.
When steering system pressure ratio work system is high, the LS4 signal of Flow amplification valve block 13 is through in logic control valve 15
Shuttle valve 23 gate the LS hydraulic fluid port that is transmitted in variable pump 1.When pilot pressure reaches a certain setting value, logic control valve is pushed
17 spool of pilot operated directional control valve in 15 commutates into figure upper, makes to turn to LS2 pressure feedback to 18 spring cavity of flow compensation valve, change
The oil liquid pressure of amount pump 1 acts on 18 epicoele of flow compensation valve.When the engine is idling, 1 output flow of variable pump is less, if
Fast steering at this time, then 1 output flow of variable pump is not enough to push logic open by the pressure difference that 13 spool of Flow amplification valve block is formed
The flow compensation valve 18 of control valve 15 does not collaborate so 1 flow of variable pump all supplies steering system to work system.Variable
The output pressure of pump 1 is to turn to operating pressure plus the pressure value of poor flow valve setting fixed in Flow amplification valve block 13, variable pump 1
Output flow depends on the aperture of 13 spool of Flow amplification valve block of steering system.When 14 slow-speed of diverter or engine speed
When raising, 1 flow of variable pump meets the corresponding required flow of diverter revolving speed, and excess traffic is formed by Flow amplification valve block 13
Pressure difference will be above 18 pressure differential resetting value of flow compensation valve on logic control valve 15, to push 18 spool of flow compensation valve, flow open
Recuperation valve 18 is opened.Pressure difference is greater than the pressure of logic control valve 15 before and after the valve of the hydraulic-control throttling valve 29 in flow control valve 5
When 21 pressure differential resetting value of recuperation valve, the pressure-compensated valve 21 in logic control valve 15 is closed, and variable pump 1 is still only to steering system at this time
System fuel feeding, not to work system fuel feeding.Pressure difference is less than setting value before and after the valve of the hydraulic-control throttling valve 29 in flow control valve 5
When, the pressure-compensated valve 21 in logic control valve 15 is slowly opened, and extra oil liquid is made to flow to work system, realizes interflow, at this time
1 output pressure of variable pump is steering system maximum pressure.
When work system is higher than steering system pressure, work system load pressure signal LS3 is through in logic control valve 15
Shuttle valve 23 gate the LS hydraulic fluid port that is transmitted in variable pump 1.When the engine is idling, 1 output flow of variable pump is small, if diverter
14 quick rotations, 1 output flow of variable pump are not enough to push open logic control valve 15 by the pressure difference that Flow amplification valve block 13 is formed
Upper flow compensation valve 18 does not collaborate so 1 flow of variable pump all supplies steering system to work system.When diverter 14 is slow
Turn or engine speed increases, 1 flow of variable pump meets the corresponding required flow of diverter revolving speed, and excess traffic is put by flow
The pressure difference that big valve block 13 is formed will be above 18 pressure differential resetting value of flow compensation valve on logic control valve 15, to push open flow-compensated
18 spool of valve, flow compensation valve 18 are opened.Pressure difference is greater than logic control before and after the valve of the hydraulic-control throttling valve 29 in flow control valve 5
When 21 pressure differential resetting value of pressure-compensated valve in valve 15 processed, the pressure-compensated valve 21 in logic control valve 15 is closed, this variations per hour
Pump 1 is still only to steering system fuel feeding, not to work system fuel feeding.Before and after the valve of the hydraulic-control throttling valve 29 in flow control valve 5
When pressure difference is less than setting value, the pressure-compensated valve 21 in logic control valve 15 is slowly opened, and extra oil liquid is made to flow to work system,
Realize interflow, 1 output pressure of variable pump is work system maximum pressure at this time.
(5) work system pressure is more than unloading valve pressure unloading.When work system pressure rise is to more than flow control valve 5
When upper pressure-control valve 30 sets pressure, pressure-control valve 30 is opened, and 2 oil liquid of constant displacement pump is returned by 31 Low-pressure load discharge of unloading valve
Fuel tank, only variable pump 1 are work system and steering system fuel feeding.
1 constant pressure stop valve of variable pump sets 25MPa pressure, when work system pressure is more than 25MPa, the pump of variable pump 1
Mouth pressure makes constant pressure stop valve commutate to diagram left position, reduces 1 swash plate angle of variable pump, subtracts interflow to work system flow
Few, when work system pressure is more than 25MPa, leading to work system flow is 0 L/min, if the not work of diverter 14 at this time
Make, then variable pump 1 is in 25MPa high pressure, 0 L/min flow state of pressure keeping at this time.If diverter 14 works, variable pump 1
Flow needed for exporting steering system.
Claims (7)
- It include variable pump (1), constant displacement pump (2), fuel tank (4), stream 1. a kind of load-sensitive formula loading machine determines variable delivery hydraulic system Control valve (5), pilot valve (7), boom cylinder (8), rotary ink tank (9), multi-way valve (10), shuttle valve block (11), Flow amplification Valve block (13), small displacement diverter (14), logic control valve (15)；Variable pump (1) passes through the CF hydraulic fluid port of logic control valve (15) It connects flux amplification valve block (13), the T1 oil return opening of logic control valve (15) is connected to fuel tank (4), and constant displacement pump (2) passes through flow control Valve (5) processed connects multi-way valve (10), and multi-way valve (10) connects rotary ink tank (9) and boom cylinder (8), it is characterised in that: described The EF hydraulic fluid port of logic control valve (15) connects multi-way valve (10) by the hydraulic-control throttling valve (29) of flow control valve (5), pilot valve (7) pilot operated directional control valve (17) the KL hydraulic fluid port and flow control valve (5) of logic control valve (15) are separately connected by shuttle valve block (11) Hydraulic-control throttling valve (29) LS8 hydraulic fluid port；When the signal pressure that shuttle valve block (11) LS6 passes to hydraulic-control throttling valve (29) LS8 hydraulic fluid port of flow control valve (5) is low, liquid When controlling pressure-compensated valve (21) closing setting pressure of throttle valve (29) the front and back pressure difference higher than logic control valve (15), variable pump (1) oil liquid is not to flow control valve (5) interflow only for steering system, and constant displacement pump (2) is according to the hydraulic-control throttlings of flow control valve (5) Flow needed for valve (29) aperture exports rotary ink tank (9) and boom cylinder (8), excess traffic oil return box (4)；When shuttle valve block (11) LS6 hydraulic fluid port passes to the signal pressure height of hydraulic-control throttling valve (29) LS8 hydraulic fluid port, and rotary ink tank (9) Flow needed for being greater than constant displacement pump (2) with flow needed for boom cylinder (8), hydraulic-control throttling valve (29) front and back pressure difference are lower than logic control When the pressure-compensated valve (21) of valve (15) closes setting pressure, variable pump (1) collaborates to flow control valve (5) to multi-way valve (10), shortcoming flow is provided.
- 2. load-sensitive formula loading machine according to claim 1 determines variable delivery hydraulic system, it is characterised in that: the flow Control valve (5) includes three-way pressure compensating device (26), damping hole (27), check valve (28), hydraulic-control throttling valve (29), pressure control Valve (30), unloading valve (31) and P6 hydraulic fluid port, P7 hydraulic fluid port, P8 hydraulic fluid port, LS7 hydraulic fluid port, LS8 hydraulic fluid port, T4 hydraulic fluid port；Three-way pressure is mended It repays the import of device (26) to be connected with P6 mouthfuls, the import of unloading valve (31), check valve (28), the outlet of three-way pressure compensating device (26) It is connect after being connected with unloading valve (31) outlet, pressure-control valve (30) outlet with T4 mouthfuls；Check valve (28) outlet is connected in P8 oil The pressure control mouth of mouth, the import of hydraulic-control throttling valve (29) and pressure-control valve (30)；The spring cavity of unloading valve (31) is connected Import in pressure-control valve (30)；P6 hydraulic fluid port connects constant displacement pump (2), and P7 hydraulic fluid port connects multi-way valve (10), P8 hydraulic fluid port and logic The EF hydraulic fluid port of control valve (15) connects, and LS7 hydraulic fluid port connection logic control valve (15) LS3 hydraulic fluid port simultaneously transmits workload signal, LS8 Hydraulic fluid port is connect with shuttle valve block (11) LS6 hydraulic fluid port；Pressure difference between the P7 hydraulic fluid port of hydraulic-control throttling valve (29), P8 hydraulic fluid port is by three-way pressure Compensator (26) setting, hydraulic-control throttling valve (29) aperture are adjusted according to the pilot signal that shuttle valve block (11) transmits, and export work Make flow needed for system.
- 3. load-sensitive formula loading machine according to claim 1 determines variable delivery hydraulic system, it is characterised in that: described patrols Collecting control valve (15) includes fixed pressure reducing valve (16), pilot operated directional control valve (17), flow compensation valve (18), pressure-compensated valve (21), shuttle valve (23), check valve (25) and P1 hydraulic fluid port, PX hydraulic fluid port, PSt hydraulic fluid port, LS1 hydraulic fluid port, LS2 hydraulic fluid port, LS3 hydraulic fluid port, KL Hydraulic fluid port, CF hydraulic fluid port, EF hydraulic fluid port, T1 hydraulic fluid port；The P1 hydraulic fluid port is connected to CF hydraulic fluid port, and P1 hydraulic fluid port is connect all the way by fixed pressure reducing valve (16) Logical PX hydraulic fluid port, another way connect PSt hydraulic fluid port through check valve (25), connect flow compensation valve (18) bullet by pilot operated directional control valve (17) Spring chamber connects EF hydraulic fluid port by flow compensation valve (18), pressure-compensated valve (21)；The LS2 hydraulic fluid port and LS3 hydraulic fluid port warp Shuttle valve (23) selection is connected to the LS1 hydraulic fluid port；The KL hydraulic fluid port is connected to pilot operated directional control valve (17) control terminal；The definite value decompression The spring cavity of valve (16) and pilot operated directional control valve (17) is connected to T1 hydraulic fluid port；The LS3 hydraulic fluid port and pressure-compensated valve (21) spring cavity Connection；CF hydraulic fluid port preferential attachment Flow amplification valve block (13), P1 hydraulic fluid port link variable pump (1), and T1 hydraulic fluid port connects fuel tank (4), KL Hydraulic fluid port is derived from the signal of shuttle valve block (11), and EF hydraulic fluid port connects flow control valve (5), and LS3 is derived from flow control valve (5) load feedback Mouthful, PX hydraulic fluid port connects diverter (14), and PSt hydraulic fluid port connects pilot valve (7)；Pressure difference between EF hydraulic fluid port and LS3 hydraulic fluid port determines pressure Whether the aperture of force compensating valve (21), control steering system collaborate and collaborate flow to work system.
- 4. load-sensitive formula loading machine according to claim 1 determines variable delivery hydraulic system, it is characterised in that: the shuttle valve block It (11) include the first shuttle valve (32), the second shuttle valve (34), third shuttle valve (35), two-way pilot operated valve device (33) and D1 hydraulic fluid port, D2 oil Mouth, C1 hydraulic fluid port, C2 hydraulic fluid port, LS5 hydraulic fluid port, LS6 hydraulic fluid port, D1 hydraulic fluid port, D2 hydraulic fluid port pass through two-way liquid after the first shuttle valve (32) gate It controls valve (33) and is connected to third shuttle valve (35) left end, C1 hydraulic fluid port, C2 hydraulic fluid port are connected to third shuttle valve after the second shuttle valve (34) gate (35) right end, third shuttle valve (35) outlet LS5 hydraulic fluid port, LS6 hydraulic fluid port；Two-way pilot operated valve device (33) control terminal and the second shuttle valve (34) outlet；LS5 hydraulic fluid port connects the KL hydraulic fluid port of logic control valve (15), and LS6 hydraulic fluid port connects the LS8 of flow control valve (5) Hydraulic fluid port；D1 hydraulic fluid port, D2 hydraulic fluid port, C1 hydraulic fluid port, C2 hydraulic fluid port connect pilot valve (7) control mouth.
- 5. load-sensitive formula loading machine according to claim 4 determines variable delivery hydraulic system, it is characterised in that: the shuttle valve block (11) C1 hydraulic fluid port, C2 hydraulic fluid port is separately connected pilot valve (7) rotating bucket control mouth A, rotating bucket control mouth C, D1 hydraulic fluid port, D2 hydraulic fluid port difference It connects pilot valve (7) swing arm control mouth B, swing arm control mouth D, C1 hydraulic fluid port/C2 hydraulic fluid port fuel injection pressure signal and pushes two-way pilot operated valve device (33) In bottom, make D1 hydraulic fluid port/D2 hydraulic fluid port signal-off.
- 6. load-sensitive formula loading machine according to claim 3 determines variable delivery hydraulic system, it is characterised in that: the logic control Valve (15) processed further includes having safety valve (19), and safety valve (19) connects P1 hydraulic fluid port and T1 hydraulic fluid port.
- 7. load-sensitive formula loading machine according to claim 1 determines variable delivery hydraulic system, it is characterised in that: the steering system System includes Flow amplification valve block (13).
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| CN107269609B (en) * | 2017-07-26 | 2018-10-26 | 无锡市钻通工程机械有限公司 | Combining hydraulic system in load-sensitive valve |
| CN107339277B (en) * | 2017-08-31 | 2024-05-14 | 潍柴雷沃智慧农业科技股份有限公司 | Tractor load sensitive type multi-way valve |
| CN107762995B (en) * | 2017-09-13 | 2023-12-22 | 江苏恒立液压科技有限公司 | Novel electric proportion overflow device |
| CN107724454B (en) * | 2017-11-10 | 2019-09-17 | 广西柳工机械股份有限公司 | Loading machine determines variable delivery hydraulic system |
| CN110578726B (en) * | 2019-09-29 | 2024-04-30 | 徐工集团工程机械股份有限公司科技分公司 | Quantitative system variable hydraulic system |
| CN110745182A (en) * | 2019-10-21 | 2020-02-04 | 三一汽车起重机械有限公司 | Auxiliary steering control system and crane |
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| CN111086558B (en) * | 2019-12-26 | 2022-02-25 | 河北雷萨重型工程机械有限责任公司 | Hydraulic power-assisted steering system, control method and engineering vehicle |
| CN111255007B (en) * | 2020-03-02 | 2021-09-14 | 浙江高宇液压机电有限公司 | Loader constant-variable hydraulic system based on load signal direct control |
| CN111677717B (en) * | 2020-05-19 | 2022-04-08 | 江苏理工学院 | Hydraulic system of hydraulic valve test bench |
| CN113494111B (en) * | 2021-07-27 | 2022-08-05 | 柳州柳工液压件有限公司 | Main control valve, fixed variable hydraulic system and loader |
| CN113669314A (en) * | 2021-08-05 | 2021-11-19 | 天津工程机械研究院有限公司 | Hydraulic system of pure electric engineering vehicle |
| CN114215797B (en) * | 2021-11-15 | 2024-04-19 | 中船华南船舶机械有限公司 | Method for controlling flow of variable pump by hydraulic system |
| CN114109936B (en) * | 2021-11-29 | 2022-10-21 | 浙江大学 | Boom hydraulic transmission system and control method thereof |
| CN114658708A (en) * | 2022-04-11 | 2022-06-24 | 华侨大学 | Load rotating speed double-sensitive anti-flow saturation system and engineering mechanical device thereof |
| CN117432673B (en) * | 2023-12-13 | 2024-02-23 | 张家口宣化英诺威克凿岩机械有限公司 | Hydraulic station, action control system and method of new energy furnace disassembly machine and electronic equipment |
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| JP5500651B2 (en) * | 2010-12-28 | 2014-05-21 | キャタピラー エス エー アール エル | Fluid pressure circuit control device and work machine |
| EP2980324B1 (en) * | 2013-03-26 | 2021-10-27 | Doosan Infracore Co., Ltd. | Hydraulic system for construction equipment |
| CN104405006B (en) * | 2014-12-16 | 2016-09-07 | 派克汉尼汾流体传动产品（上海）有限公司 | Loading machine semi-variety hydraulic system |
| CN104929183B (en) * | 2015-05-21 | 2017-03-15 | 徐工集团工程机械股份有限公司科技分公司 | A kind of loader turned to based on Flow amplification determines variable delivery hydraulic system |
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Address after: 317000 358, zhe Road, Dayang street, Taizhou, Zhejiang. Applicant after: Zhejiang Gaoyu Hydraulic Mechanical and Electrical Co., Ltd. Address before: 317000 No. 358, extension Road, Dayang street, Taizhou, Zhejiang. Applicant before: Zhejiang Gaoyu Hydraulic Mechanical and Electrical Co., Ltd. |
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