CN107882798A - Load simulation valve and loading machine variable system - Google Patents
Load simulation valve and loading machine variable system Download PDFInfo
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- CN107882798A CN107882798A CN201711102334.XA CN201711102334A CN107882798A CN 107882798 A CN107882798 A CN 107882798A CN 201711102334 A CN201711102334 A CN 201711102334A CN 107882798 A CN107882798 A CN 107882798A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/021—Valves for interconnecting the fluid chambers of an actuator
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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
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Abstract
The present invention relates to a kind of hydraulic system, to solve the shortcomings that inlet pressure of load-sensitive valve and the big load pressure pressure difference of load-sensitive valve extraction in existing load-reacting system, there is provided a kind of load simulation valve and loading machine variable system.Including steering hydraulic system and hydraulic system of working, steering hydraulic system includes steering variable pump, pressure-gradient control valve, steering gear, steering cylinder etc.；Hydraulic system of working includes operating variable pump, distributing valve, hydraulic pressure executive item, pilot valve, shuttle valve group etc.；When pilot handle has action, the load signal that will be produced on distributing valve, pass to and be connected to the second load simulation valve that first load simulation valve and working barrel to distributing valve of the steering pump to distributing valve bypass bypass, utilize the difference of the active area of two pressure differences on load simulation valve, the pressure difference for the load pressure that pump is produced with distributing valve is amplified, and the differential pressure action most amplified at last realizes system variable control on the flow control valve of pump.
Description
Technical field
The present invention relates to a kind of hydraulic system, more specifically to a kind of load simulation valve and loading machine variable system.
Background technology
For the characteristic realized control accuracy height and more saved, it is at most negative to be applied in loader hydraulic system
Carry sensitive variable system.The main hydraulic of load-reacting system includes load-reacting pump, load-sensitive distributes
Valve, load-sensitive flux amplification valve etc..Wherein load-sensitive distributing valve can become according to the size of valve port opening to load-sensitive
Measure pump feedback load pressure signal, load-reacting pump is exported corresponding flow according to valve port opening, avoid energy-conservation and
Spill losses, realize the purpose that control accuracy is high and saves.But load-reacting system is in order to realize that above-mentioned control is special
Property, variable pump and distributing valve extraction load pressure must consume certain pressure difference, the pressure difference generally 1.6Mpa~2.5Mpa it
Between, pressure difference is larger.And load-sensitive distributing valve is import partses, procurement cycle length, cost are higher.
The content of the invention
The technical problem to be solved in the present invention is for existing loading machine load-reacting system pump intake pressure and distribution
The problem of load pressure pressure difference of valve extraction is big, and a kind of load simulation valve and loading machine variable system are provided.
The present invention is such to realize the technical scheme of its purpose：There is provided a kind of load simulation valve, it is characterised in that bag
Two-position three-way valve, two position four-way valves, guiding valve are included, and with P1 hydraulic fluid ports, pressure signal delivery outlet, the fuel tank being connected with outside oil circuit
Circuit interface, pressure signal input port, guide's hydraulic fluid port；
The guiding valve includes valve element and the valve pocket being connected with the valve element of two position four-way valves, along valve element between valve element and valve pocket
It is axial arranged to have C1 chambers, C2 chambers, C3 chambers, C4 chambers, C5 chambers, C6 chambers；Wherein C1 chambers and C6 chambers are respectively positioned at the both ends of valve element and chamber
Active area of the interior hydraulic oil on valve element is identical, and the active area of the intracavitary hydraulic oil of C2 chambers and C5 chambers on valve element is identical,
C3 chambers and C4 chambers are adjacent and connected by relatively moving formed pressure relief valve port between valve element and valve pocket.
The two-position three-way valve has A1 hydraulic fluid ports, A2 hydraulic fluid ports, A3 hydraulic fluid ports, and two position four-way valve has B1 hydraulic fluid ports, B2 oil
Mouth, B3 hydraulic fluid ports, B4 hydraulic fluid ports.
The A2 hydraulic fluid ports and B2 hydraulic fluid ports are to be used for and the loop-coupled fuel tank circuit interface of fuel tank；The A1 hydraulic fluid ports and B1
Hydraulic fluid port is connected with P1 hydraulic fluid ports；The hydraulic control end of two-position three-way valve and two position four-way valves connects with guide's hydraulic fluid port；A3 hydraulic fluid ports and C1
Chamber connects, and B4 hydraulic fluid ports connect with C3 chambers and C5 chambers simultaneously, and B3 hydraulic fluid ports connect with C2 chambers；Pressure signal delivery outlet simultaneously with C2 chambers and
C4 chambers connect, and pressure signal input port connects with C6 chambers.
When guide's hydraulic fluid port has effective pilot pressure signal input, A1 hydraulic fluid ports turn on A3 hydraulic fluid ports, B1 hydraulic fluid ports and B4 hydraulic fluid ports
Conducting, B3 hydraulic fluid ports connect through damping hole with B2 hydraulic fluid ports；When guide's hydraulic fluid port does not have effective pilot pressure signal input, A3 hydraulic fluid ports and A2
Hydraulic fluid port turns on, and B2 hydraulic fluid ports turn on B3 hydraulic fluid ports and B4 hydraulic fluid ports simultaneously.
In above-mentioned load simulation valve, the C6 intracavitary is provided with back-moving spring.
The present invention is such to realize the technical scheme of its purpose：A kind of loading machine variable system is provided, including turned to
Hydraulic system and hydraulic system of working.
The hydraulic steering system includes steering cylinder, is connected with steering cylinder and controls the flexible steering of steering cylinder
The steering of pressure-gradient control valve, pumping hole and pressure-gradient control valve work oil inlet connection that device, preferential oil-feed port are connected with steering gear work oil inlet
Variable pump, the hydraulic oil container being connected with steering variable pump oil inlet.
The hydraulic system of working includes boom cylinder and rotary ink tank, is connected and controls with boom cylinder and rotary ink tank
What boom cylinder and rotary ink tank stretched closes the uncompensated distributing valve of middle position, the pilot valve being connected with distributing valve, pumping hole and distributing valve
The connection of work oil inlet and the operating variable pump that is connected with hydraulic oil container of oil inlet.
The flow more than needed interflow oil-out of the pressure-gradient control valve is connected with the work oil inlet of the distributing valve.
Characterized by further comprising shuttle valve, shuttle valve group and two foregoing load simulation valves, the load simulation described in two
Valve is respectively the first load simulation valve and the second load simulation valve.
After the connection of the load signal delivery outlet of the steering pressure signal output of the steering gear and pressure-gradient control valve with the shuttle
The pressure signal delivery outlet of the oil inlet connection of valve, another oil inlet of the shuttle valve and the first load simulation valve 8 connects
Connect, the oil-out of the shuttle valve is connected with the load feedback mouth of steering variable pump.
The connection corresponding with each oil inlet of shuttle valve group of each guide's oil circuit of the pilot valve, the oil-out of shuttle valve group simultaneously with
Guide's hydraulic fluid port of first load simulation valve and the second load simulation valve connects, the P1 hydraulic fluid ports and steering variable of the first load simulation valve
The pumping hole connection of pump, the P1 hydraulic fluid ports of the second load simulation valve are connected with the pumping hole of operating variable pump；The load pressure of the distributing valve
Power delivery outlet is connected with the pressure signal input port of the first load simulation valve and the second load simulation valve simultaneously；Second load simulation
The pressure signal delivery outlet of valve is connected with the load feedback mouth of operating variable pump.
In above-mentioned loading machine variable system, in addition to guide's delivery valve, the oil inlet of guide's delivery valve become with turning to
The pumping hole connection of pump is measured, the oil-out of guide's delivery valve and the pilot control oil inlet of pilot valve connect.
In above-mentioned loading machine variable system, the connection oil between the oil inlet and steering variable pump pumping hole of guide's delivery valve
Guide's oily filter is provided with road.
In above-mentioned loading machine variable system, between the oil-out of guide's delivery valve and the pilot control oil inlet of pilot valve
Connection oil circuit on be provided with guide check valve.
The present invention compared with prior art, advantages of the present invention：
(1) a kind of load simulation valve and loading machine variable system provided using patent of the present invention, can be greatly reduced pump
The pressure difference of mouth and distributing valve feedback pressure, compared to the load sensitive control system of classics, more save；
(2) i.e. achievable Variable Control is used in combination with the common middle position distributing valve that closes in load simulation valve, compared to tradition
Load-sensitive distributing valve, distribute valve arrangement and principle it is simpler, manufacturing cost is lower, substantially reduce complete machine hydraulic system into
This.
Brief description of the drawings
Fig. 1 is the schematic diagram of the first load simulation valve of the present invention.
Fig. 2 is the schematic diagram of the second load simulation valve of the present invention.
Fig. 3 is the schematic diagram of the loading machine variable system of the present invention.
Parts title and sequence number in figure：
Steering variable pump 1, pressure-gradient control valve 2, steering gear 3, steering cylinder 4, boom cylinder 5, bucket cylinder 6, shuttle valve 7, first
Load simulation valve 8, two-position three-way valve 81, two position four-way valves 82, guiding valve 83, the second load simulation valve 9, shuttle valve group 10, work become
Measure pump 11, guide's oily filter 12, distributing valve 13, pilot valve 14, guide check valve 15, guide's delivery valve 16, hydraulic oil container 17.
Embodiment
Illustrate specific embodiment below in conjunction with the accompanying drawings.
Loading machine variable system in the present embodiment is as shown in figure 3, the system includes steering hydraulic system and working hydraulic pressure
System, shuttle valve 7, shuttle valve group 10 and two load simulation valves, guide's delivery valve 16 etc..
Steering hydraulic system includes steering cylinder 4, is connected with steering cylinder 4 and controls the flexible steering gear of steering cylinder 4
3rd, the work oil inlet of pressure-gradient control valve 2, pumping hole and pressure-gradient control valve 2 that preferential oil-feed port CF is connected with the work oil inlet of steering gear 3 connects
The steering variable pump 1 connect, the hydraulic oil container 17 being connected with the oil inlet of steering variable pump 1.Steering variable pump 1 is from hydraulic oil container 17
Middle draw oil simultaneously exports from its pumping hole, and the hydraulic oil that steering variable pump 1 exports enters excellent from the work oil inlet of pressure-gradient control valve 2
First valve 2, exported from the preferential oil-feed port CF of pressure-gradient control valve 2 to the fuel feeding of steering gear 3, flow of having more than needed then closes from the flow more than needed of pressure-gradient control valve
Flow out hydraulic fluid port output.
Hydraulic system of working includes boom cylinder 5 and rotary ink tank 6, is connected and controls with boom cylinder 5 and rotary ink tank 6
Its flexible work for closing the uncompensated distributing valve 13 of middle position, the pilot valve 14 being connected with distributing valve 13, pumping hole and distributing valve 14 is entered
The operating variable pump 11 that hydraulic fluid port is connected and oil inlet is connected with hydraulic oil container 17.
The flow more than needed interflow oil-out EF of pressure-gradient control valve 2 is connected with the work oil inlet of distributing valve 13；The institute of steering variable pump 1
The hydraulic oil of output it is preferential meet flow needed for steering gear 3 in the case of by flow more than needed and operating variable pump 11 collaborate to point
With the fuel feeding of valve 13.
Two load simulation valves are respectively the first load simulation valve 8 and the second load simulation valve 9.
As shown in figure 1, the first load simulation valve 8 includes two-position three-way valve 81, two position four-way valves 82, guiding valve 83, and have
The P1 hydraulic fluid ports that are connected with outside oil circuit, pressure signal delivery outlet LSO, fuel tank circuit interface, pressure signal input port LSI, guide
Hydraulic fluid port P10.
In the first load simulation valve, guiding valve 83 includes valve element and the valve pocket being connected with the valve element of two position four-way valves 82, sliding
Valve 83 is axially disposed with C1 chambers, C2 chambers, C3 chambers, C4 chambers, C5 chambers, C6 chambers between valve element and valve pocket along valve element；Wherein C1 chambers and
Active area of the C6 chambers respectively positioned at the both ends and intracavitary hydraulic oil of valve element on valve element is S1, C2 chambers and C5 intracavitary hydraulic oil
Active area on valve element is S2, and C3 chambers and C4 chambers are adjacent, when being relatively moved between valve element and valve pocket, valve element and valve pocket
Between the pressure relief valve port connection C3 chambers and C4 chambers that are formed.
In the first load simulation valve 8, two-position three-way valve 81 has A1 hydraulic fluid ports, A2 hydraulic fluid ports, A3 hydraulic fluid ports, two position four-way valves 82
With B1 hydraulic fluid ports, B2 hydraulic fluid ports, B3 hydraulic fluid ports, B4 hydraulic fluid ports.
In the first load simulation valve 8, A2 hydraulic fluid ports and B2 hydraulic fluid ports are to be used to connect with the loop-coupled fuel tank loop of fuel tank
Mouthful；A1 hydraulic fluid ports and B1 hydraulic fluid ports are connected with P1 hydraulic fluid ports；The hydraulic control end A0 of two-position three-way valve 81 and two position four-way valves 82 hydraulic control end
B0 connects with guide's hydraulic fluid port P10；A3 hydraulic fluid ports connect with C1 chambers, and B4 hydraulic fluid ports connect with C3 chambers and C5 chambers simultaneously, B3 hydraulic fluid ports and C2
Chamber connects；Pressure signal delivery outlet LSO connects with C2 chambers and C4 chambers simultaneously, and pressure signal input port LSI connects with C6 chambers；C6 chambers
Inside it is provided with back-moving spring.The rigidity very little of back-moving spring, the elastic force that it is acted on valve element is compared with hydraulic fluid pressure
It is very small, it can be ignored.
In the first load simulation valve 8, when guide's hydraulic fluid port P10 has effective pilot pressure signal input, two-position three-way valve
81 are in right position, and A1 hydraulic fluid ports turn on A3 hydraulic fluid ports, and two position four-way valves 82 are in left position, and B1 hydraulic fluid ports turn on B4 hydraulic fluid ports, B3 hydraulic fluid ports
Connected through damping hole R1 with B2 hydraulic fluid ports；When guide's hydraulic fluid port P10 does not have effective pilot pressure signal input, two-position three-way valve 81 is in
Zuo Wei, A3 hydraulic fluid port turn on A2 hydraulic fluid ports, and two position four-way valves 82 are in right position, and B2 hydraulic fluid ports turn on B3 hydraulic fluid ports and B4 hydraulic fluid ports simultaneously.
As shown in Fig. 2 the second load simulation valve 9 includes two-position three-way valve 91, two position four-way valves 92, guiding valve 93, and have
The P1 hydraulic fluid ports that are connected with outside oil circuit, pressure signal delivery outlet LSO, fuel tank circuit interface, pressure signal input port LSI, guide
Hydraulic fluid port P10.
In the second load simulation valve 9, guiding valve 93 includes valve element and the valve pocket being connected with the valve element of two position four-way valves 92, sliding
Valve 93 is between valve element and valve pocket along the axial arranged C1 chambers of valve element, C2 chambers, C3 chambers, C4 chambers, C5 chambers, C6 chambers；Wherein C1 chambers and
Active area of the C6 chambers respectively positioned at the both ends and intracavitary hydraulic oil of valve element on valve element is S3, C2 chambers and C5 intracavitary hydraulic oil
Active area on valve element is S4, and C3 chambers and C4 chambers are adjacent, when being relatively moved between valve element and valve pocket, valve element and valve pocket
Between the pressure relief valve port connection C3 chambers and C4 chambers that are formed.
In the second load simulation valve 9, two-position three-way valve 91 has A1 hydraulic fluid ports, A2 hydraulic fluid ports, A3 hydraulic fluid ports, two position four-way valves 92
With B1 hydraulic fluid ports, B2 hydraulic fluid ports, B3 hydraulic fluid ports, B4 hydraulic fluid ports.
In the second load simulation valve 9, A2 hydraulic fluid ports and B2 hydraulic fluid ports are to be used to connect with the loop-coupled fuel tank loop of fuel tank
Mouthful；A1 hydraulic fluid ports and B1 hydraulic fluid ports are connected with P1 hydraulic fluid ports；The hydraulic control end A0 of two-position three-way valve 91 and two position four-way valves 92 hydraulic control end
B0 connects with guide's hydraulic fluid port P10；A3 hydraulic fluid ports connect with C1 chambers, and B4 hydraulic fluid ports connect with C3 chambers and C5 chambers simultaneously, B3 hydraulic fluid ports and C2
Chamber connects；Pressure signal delivery outlet LSO connects with C2 chambers and C4 chambers simultaneously, and pressure signal input port LSI connects with C6 chambers.C6 chambers
Inside it is provided with back-moving spring.The rigidity very little of back-moving spring, the elastic force that it is acted on valve element is compared with hydraulic fluid pressure
It is very small, it can be ignored.
In the second load simulation valve 9, when guide's hydraulic fluid port P10 has effective pilot pressure signal input, two-position three-way valve
91 are in left position, and A1 hydraulic fluid ports turn on A3 hydraulic fluid ports；Two position four-way valves 92 are in right position, and B1 hydraulic fluid ports turn on B4 hydraulic fluid ports, B3 hydraulic fluid ports
Connected through damping hole R2 with B2 hydraulic fluid ports；When guide's hydraulic fluid port P10 does not have effective pilot pressure signal input, two-position three-way valve 91 is in
Right position, A3 hydraulic fluid ports turn on A2 hydraulic fluid ports；Two position four-way valves 92 are in left position, and B2 hydraulic fluid ports turn on B3 hydraulic fluid ports and B4 hydraulic fluid ports simultaneously.
As shown in figure 1, the steering pressure signal output LS3 of steering gear 3 and the load pressure signal delivery outlet of pressure-gradient control valve 2
It is connected after LS2 connections with an oil inlet 7a of shuttle valve 7, the pressure of another oil inlet 7b of shuttle valve 7 and the first load simulation valve 8
The LSO connections of force signal delivery outlet, the oil-out 7c of shuttle valve 7 are connected with the load feedback mouth LS1 of steering variable pump 1.
The connection corresponding with each oil inlet of shuttle valve group 10 of each guide's oil circuit of pilot valve 14, the oil-out of shuttle valve group 10 is simultaneously
Be connected with guide's hydraulic fluid port P10 of the first load simulation valve 8 and the second load simulation valve 9, the P1 hydraulic fluid ports of the first load simulation valve 8 with
The pumping hole connection of steering variable pump 1, the P1 hydraulic fluid ports of the second load simulation valve 9 are connected with the pumping hole of operating variable pump 11；Distributing valve
13 load pressure delivery outlet LS5 while the pressure signal input port with the first load simulation valve 8 and the second load simulation valve 9
LSI connections；The pressure signal delivery outlet LSO of the second load simulation valve 9 and load feedback mouth LS7 of operating variable pump.
The oil inlet of guide's delivery valve 16 is connected with the pumping hole of steering variable pump 1, the oil-out of guide's delivery valve 16 and elder generation
The pilot control oil inlet connection of pilot valve 14.Company between the oil inlet of guide's delivery valve 16 and the pumping hole of steering variable pump 1
Connect and guide's oily filter 12 is provided with oil circuit.Between the oil-out of guide's delivery valve 16 and the pilot control oil inlet of pilot valve 14
Connection oil circuit on be provided with guide check valve 15.
The operation principle of loading machine variable system is as follows in the present embodiment：
First, complete machine idling attonity operating mode, pilot valve 14 exports without pilot pressure, corresponding with 14 each guide's oil circuit of pilot valve
Without effectively at guide's hydraulic fluid port P10 of the outlet of the shuttle valve group 10 of connection namely the first load simulation valve 8 and the second load simulation valve 9
Pilot pressure.
In the first load simulation valve 8, two-position three-way valve 81 is in left position, and two position four-way valves 82 are in right position.Due to two
Position four-way valve 82 moves without commutation, the valve pocket without motion of guiding valve 83.The left position that the C1 chambers of guiding valve 83 pass through two-position three-way valve 81
With fuel tank circuit communication, the pressure of C1 chambers is zero；The right side that C2 chambers, C3 chambers, C4 chambers, the C5 chambers of guiding valve 83 pass through two position four-way valves 82
Position and fuel tank circuit communication, C2 chambers, C3 chambers, C4 chambers, the pressure of C5 chambers are zero；The load pressure delivery outlet LS5 of distributing valve 13
Unloading pressure signal output, the pressure with the C6 chambers of the load pressure delivery outlet LS5 guiding valves 83 being connected is zero；The valve of guiding valve 83
The covering amount X0 of the equal no pressure of each chamber of core, the valve element without motion of guiding valve 83, valve element and valve pocket is zero (between C3 chambers and C4 chambers not
Connection).The steering pressure signal output LS3 of steering gear 3 is turned on by steering gear middle position with fuel tank loop, is turned to steering gear
The oil inlet 7a for the shuttle valve 7 that pressure signal delivery outlet LS3 is connected pressure is zero；Due to the C2 chambers of guiding valve 83 and the pressure of C4 chambers
Power is zero, and another oil inlet 7b pressure for the shuttle valve 7 being connected with the C2 chambers and C4 chambers of guiding valve 83 is also zero；Therefore, shuttle valve 7
Oil-out 7c pressure is zero, the pressure with the load feedback mouth LS1 of the oil-out 7c of the shuttle valve 7 steering variable pumps 1 being connected
Also it is zero.Now, the pumping hole of steering variable pump 1 maintains a low pressure, and discharge capacity is almost nil, does not open middle bit-loss；
In the second load simulation valve 9, its two-position three-way valve 91 is in right position, and two position four-way valves 92 are in left position.Due to
Two position four-way valves 92 move without commutation, the valve pocket without motion of guiding valve 93.The right side that the C1 chambers of guiding valve 93 pass through two-position three-way valve 91
Position connection fuel tank loop, the pressure of C1 chambers is zero；The left side that C2 chambers, C3 chambers, C4 chambers, the C5 chambers of guiding valve 93 pass through two position four-way valves 92
Position connection fuel tank loop, C2 chambers, C3 chambers, C4 chambers, the pressure of C5 chambers are zero；The load pressure delivery outlet LS5 of distributing valve 13 also without
Load pressure signal exports, and the pressure with the C6 chambers of the load pressure delivery outlet LS5 guiding valves 93 being connected is zero；The valve element of guiding valve 93
The equal no pressure of each oil pocket, the valve element without motion of guiding valve 93, the covering amount X1 of valve element and valve pocket is zero (between C3 chambers and C4 chambers not
Connection).Because the C2 chambers of guiding valve 93 and the pressure of C4 chambers are zero, the operating variable pump that is connected with the C2 chambers and C4 chambers of guiding valve 93
11 load feedback mouth LS7 pressure is zero.Now, the pumping hole of operating variable pump 11 maintains a low pressure, and discharge capacity is almost nil,
Middle bit-loss is not opened；
2nd, independent steering situation, pilot valve 14 is without output pressure, the shuttle valve of connection corresponding with 14 each guide's oil circuit of pilot valve
The guide hydraulic fluid port P10 no pressures input of the outlet connection of group 10.
In the second load simulation valve 9, its two-position three-way valve 91 is in right position, and two position four-way valves 92 are in left position.Due to
Two position four-way valves 92 move without commutation, the valve pocket without motion of guiding valve 93.The right side that the C1 chambers of guiding valve 93 pass through two-position three-way valve 91
Position connection fuel tank loop, the pressure of C1 chambers is zero；The left side that C2 chambers, C3 chambers, C4 chambers, the C5 chambers of guiding valve 93 pass through two position four-way valves 92
Position connection fuel tank loop, C2 chambers, C3 chambers, C4 chambers, the pressure of C5 chambers are zero；The load pressure delivery outlet LS5 of distributing valve 13 also without
Load pressure signal exports, and the pressure with the C6 chambers of the load pressure delivery outlet LS5 guiding valves 93 being connected is zero；The valve element of guiding valve 93
The equal no pressure of each oil pocket, the valve element without motion of guiding valve 93, the covering amount X1 of valve element and valve pocket is zero (between C3 chambers and C4 chambers not
Connection).Because the C2 chambers of guiding valve 93 and the pressure of C4 chambers are zero, the operating variable pump that is connected with the C2 chambers and C4 chambers of guiding valve 93
11 load feedback mouth LS7 pressure is zero.Now, the pumping hole of operating variable pump 11 maintains a low pressure, and discharge capacity is almost nil,
Middle bit-loss is not opened；
In the first load simulation valve 8, two-position three-way valve 81 is in left position, and two position four-way valves 82 are in right position.Due to two
Position four-way valve 82 moves without commutation, the valve pocket without motion of guiding valve 83.The left position that the C1 chambers of guiding valve 83 pass through two-position three-way valve 81
With fuel tank circuit communication, the pressure of C1 chambers is zero；The right side that C2 chambers, C3 chambers, C4 chambers, the C5 chambers of guiding valve 83 pass through two position four-way valves 82
Position and fuel tank circuit communication, C2 chambers, C3 chambers, C4 chambers, the pressure of C5 chambers are zero；The load pressure delivery outlet LS5 of distributing valve 13
Unloading pressure signal output, the pressure with the C6 chambers of the load pressure delivery outlet LS5 guiding valves 83 being connected is zero；The valve of guiding valve 83
The covering amount X0 of the equal no pressure of each oil pocket of core, the valve element without motion of guiding valve 83, valve element and valve pocket is zero.Due to the C2 of guiding valve 83
The pressure of chamber and C4 chambers is zero, and the oil inlet 7b pressure for the shuttle valve 7 being connected with the C2 chambers and C4 chambers of guiding valve 83 is also zero；Turn to
When device 3 has action, the steering pressure signal output LS3 of steering gear 3 is connected with the load pressure signal delivery outlet LS2 of pressure-gradient control valve 2
After logical, while the oil inlet 7a for passing through shuttle valve 7 is delivered to the load feedback mouth LS1 of steering variable pump 1 so that steering variable pump 1
Increase discharge capacity, until meeting the flow required for steering.
3rd, executive component (boom cylinder Huo and rotary ink tank) single movement operating mode, when pilot valve 14 has action, push away
The 13 corresponding main valve stem motion of dynamic distributing valve makes main valve stem have certain opening, and the pilot pressure that pilot valve 14 exports also passes through shuttle
The oil-out of valve group 10 is delivered to guide hydraulic fluid port P10, is applied to respectively on the first load simulation valve 8 and the second load simulation valve 9.
The right-hand member (hydraulic control end A0) of the two-position three-way valve 81 of first load simulation valve 8 and the left end (liquid of two position four-way valves 82
Control end B0), under first oil diverting port P10 pressure oil effect, promote the position four-way valve 82 of two-position three-way valve 81 and two to commutate.Guiding valve 83
Valve pocket follow two position four-way valves 82 to move right so that between the C3 chambers and C4 chambers of guiding valve 83 occur an amount of opening X0 (i.e.
The aperture of pressure relief valve port).The pump intake pressure of steering variable pump 1 is applied to the C1 chambers of guiding valve 83 by the right position of two-position three-way valve 81,
The load pressure of the load pressure delivery outlet output of distributing valve 13 is applied to the C6 chambers of guiding valve 83, be applied to the pressure P1 of C1 chambers with
It is applied to the load pressure PLS5 of C6 chambers pressure difference direction to the right, active area is S1；Meanwhile the pumping hole of steering variable pump 1
It is divided into two-way after the left position effect that pressure P1 passes through two position four-way valves 82, is applied to the C5 chambers of guiding valve 83 all the way, is applied to all the way
C3 chambers, the pressure P1 for being applied to C3 chambers realize decompression by amount of opening X0 pressure relief valve port, and the pressure after decompression is PLS4, effect
Fuel tank loop is transferred to the C4 chambers of guiding valve 83, and by the damping hole R1 of C2 chambers, two position four-way valves, 82 left position.It is applied to C5 chambers
Pressure PLS4s (pressure of C2 chamber with the pressure of C4 chamber equal) of the pressure P1 with being applied to C2 chambers pressure difference direction to the left, effect
Area is S2.
Due to the attonity of steering gear 3, the pressure of steering pressure signal output LS3 outputs is zero, turns to and presses with steering gear
The oil inlet 7a of shuttle valve 7 connected force signal delivery outlet LS3 pressure is zero；The pressure PLS4 of C2 chambers is applied to, passes through shuttle valve 7
Oil inlet 7b, oil-out 7c be ultimately transferred to the load feedback mouth LS1 mouths of steering variable pump so that steering variable pump 1 increases
Discharge capacity is until flow needed for distributing valve.
For guiding valve 83, due to back-moving spring rigidity very little, if ignoring spring force, pressure P1 and C6 of the valve element by C1 chambers
The pressure PLS5 of chamber, the pressure difference that active area is S1, and the pressure P1 of C5 chambers and C2 chambers pressure PLS4, active area S2
Pressure difference, valve element 83 reaches poised state in the presence of two this pressure differences.Because S1 is S2 N1 times (2≤N1≤3), effect
Pressure difference to the pressure P1 and the pressure PLS4 for being applied to C2 chambers of C5 chambers is to be applied to the pressure P1 of C1 chambers and be applied to C6 chambers
N1 times (2≤N1≤3) of pressure PLS5 pressure difference.The pressure difference for being applied to PLS4s of the pressure P1 of C5 chambers with being applied to C2 chambers is
The pressure difference being applied on the flow control valve of steering variable pump 1, i.e.,：By the first load simulation valve 8, steering variable pump is realized
1 pump intake pressure P1 and the load pressure PLS5 of distributing valve extraction pressure difference amplification, and the pressure difference signal most amplified at last is applied to
On the flow control valve of steering variable pump 1, reach the purpose of system variable control.
The left end (hydraulic control end A0) of the two-position three-way valve 91 of second load simulation valve 9 and the right-hand member (liquid of two position four-way valves 92
Control end B0) formerly in the presence of oil diverting port P10 pressure oil oil, promote the position four-way valve 92 of two-position three-way valve 91 and two to commutate.Guiding valve
93 valve pocket follows two position four-way valves 92 to left movement so that the C3 chambers of guiding valve an amount of opening X1 occur with C4 chambers and (depressurized
The aperture of valve port).The pump intake pressure oil of operating variable pump 1 is applied to the C1 chambers of guiding valve 93 by the left position of two-position three-way valve 91,
The load pressure for the load pressure delivery outlet output that distributing valve 13 exports is applied to the C6 chambers of guiding valve 93, is applied to the pressure of C1 chambers
To the left, active area is S3 in pressure PLS5 of the P2 with being applied to C6 chambers pressure difference direction；Meanwhile the pumping hole pressure of operating variable pump 1
It is divided into two-way after the right position effect that power P2 passes through two position four-way valves 92, is applied to the C5 chambers of guiding valve 93 all the way, is applied to C3 all the way
Chamber, the pressure P2 for being applied to C3 chambers realize decompression by amount of opening X1, and the pressure after decompression is PLS6, is applied to the C4 of guiding valve 9
Chamber, and fuel tank loop is transferred to by the damping hole R2 of C2 chambers, two position four-way valves, 92 right position.The pressure P2 of C5 chambers is applied to making
Use the pressure PLS6 of C2 chambers pressure difference direction to the right, active area is S4；
The pressure PLS6 (pressure of C2 chambers is equal with the pressure of C4 chambers) of C2 chambers is applied to, passes to operating variable pump 11
Load feedback mouth LS7 mouths so that operating variable pump 11 increases discharge capacity until flow needed for distributing valve.
For guiding valve 93, due to spring rate very little, if ignoring spring force, valve element by act on the pressure P2 of C1 chambers with
Pressure PLS5, the active area for being applied to C6 chambers are S3 pressure difference, and act on the pressure P2 of C5 chambers and be applied to C2 chambers
Pressure PLS6, the pressure difference that active area is S4, valve element 93 reach poised state in the presence of two pressure differences.Because S3 is S4
N2 times (2≤N2≤3), the pressure P2 for acting on C5 chambers and the pressure PLS6 for being applied to C2 chambers pressure difference are the pressures for acting on C1 chambers
N2 times (2≤N2≤3) of pressure PLS5s of the power P2 with acting on C6 chambers pressure difference.Act on the pressure P2 of C5 chambers and act on C2
The pressure PLS6 of chamber pressure difference is the pressure difference being applied on the flow control valve of operating variable pump 11, i.e.,：Pass through the second load
Analog valve 9, the amplification of the pressure difference for the load pressure PLS5 that the pump intake pressure P2 of operating variable pump 1 produces with distributing valve 13 is realized,
And the pressure difference signal most amplified at last is applied on the flow control valve of operating variable pump 11, reach the mesh of system variable control
's.
4th, executive component single movement operating mode, when pilot valve 14 has action and continues increase, promote distributing valve 13 corresponding
Valve rod continue increase opening, pilot valve 14 export pilot pressure also by shuttle valve group 10 to guide hydraulic fluid port P10, make respectively
Use on the first load simulation valve 8 and the second load simulation valve 9.
Because the opening of main valve stem increases, inlet pressure P3 and load pressure delivery outlet the LS5 extraction of distributing valve 13 are born
Carrying pressure PLS5 pressure difference reduces, and being applied to the C1 chambers of the first load simulation valve 8, pressure difference also reduces to the right with C6 chambers, direction, cunning
The valve element of valve 83 is moved to the left, amount of opening X0 increases so that the depressurization for being applied to the pressure P1 of C3 chambers weakens, the pressure of C2 chambers
Power PLS4 is raised, that is, being applied to the pressure difference of C5 chambers with C2 chambers, direction to the left reduces, and the valve element of guiding valve 83 starts to move right, opened
Mouth amount X0 reduces, and is finally reached poised state.Because the pressure PLS4 of C2 chambers is raised, pass through oil inlet 7b, the oil-out of shuttle valve 7
7c is delivered to the load feedback mouth LS1 of steering variable pump 1 pressure rise, is pushed to the flow control valve of steering variable pump 1
Right position, and then steering variable pump 1 is increased discharge capacity, until meeting the traffic demand of distributing valve 13.
Because the opening of the main valve stem of distributing valve 13 increases, the inlet pressure P3 and load pressure delivery outlet LS5 of distributing valve 13
Pressure difference reduce, being applied to the C1 chambers of the second load simulation valve 9, pressure difference also reduces to the left with C6 chambers, direction, the valve element of guiding valve 93
Move right, amount of opening X1 increases so that the depressurization for being applied to the pressure P2 of C3 chambers weakens, the pressure PLS6 liters of C2 chambers
Height, that is, being applied to the pressure difference of C5 chambers with C2 chambers, direction to the right reduces, and the valve element of guiding valve 83 starts to be moved to the left, and amount of opening X1 subtracts
It is small, it is finally reached poised state.Because the pressure PLS6 of C2 chambers is raised, the load feedback mouth LS7 of operating variable pump 11 is delivered to
Pressure rise, the flow control valve of operating variable pump 11 is pushed to right position, so make operating variable pump 11 increase discharge capacity, directly
To the traffic demand for meeting distributing valve 13.
5th, when steering and work system act simultaneously, the load of the load pressure delivery outlet output of distributing valve 13
Pressure is applied to the first load simulation valve 8 and the second load simulation valve 9 simultaneously, and negative by the first load simulation valve 8 and second
Analog valve 9 is carried, makes the pressure signal delivery outlet LSO output pressures PLS4 of the first load simulation valve 8, the pressure of the second load simulation valve
Signal output LSO output pressure signals PLS6.
The load feedback mouth LS7 mouths of operating variable pump 11 receive the pressure signal delivery outlet LSO of the second load simulation valve
After the pressure signal P LS6 of output, increase discharge capacity, until distributing valve traffic demand.
Because steering gear acts simultaneously, the steering pressure signal PLS3 of the steering pressure signal output output of steering gear 3
Converged with the pressure signal P LS2 phases of pressure-gradient control valve output and be applied to the oil inlet 7a of shuttle valve 7；The first load simulation valve 8 exports simultaneously
Pressure signal P LS4 be applied to the oil inlet 7b of shuttle valve 7；By the comparison of shuttle valve 7, larger pressure signal is produced, and pass through
Oil-out 7c is eventually transferred to the load feedback mouth LS1 of steering variable pump 1, and the flow that steering variable pump 1 exports preferentially meets to turn
To outside the demand of system, flow ECDC more than needed outflow hydraulic fluid port EF supply hydraulic systems.
Claims (6)
1. a kind of load simulation valve, it is characterised in that including two-position three-way valve, two position four-way valves, guiding valve, and with oily with outside
P1 hydraulic fluid ports, pressure signal delivery outlet (LSO), fuel tank circuit interface, pressure signal input port (LSI), the guide's hydraulic fluid port of road connection
(P10)；
The guiding valve includes valve element and the valve pocket being connected with the valve element of two position four-way valves, along valve element axial direction between valve element and valve pocket
It is disposed with C1 chambers, C2 chambers, C3 chambers, C4 chambers, C5 chambers, C6 chambers；Wherein C1 chambers and C6 chambers are respectively positioned at the both ends of valve element and intraluminal fluid
Press oil that active area on valve element is identical, the active area of the intracavitary hydraulic oil of C2 chambers and C5 chambers on valve element is identical, C3 chambers
And C4 chambers are adjacent and connected by relatively moving formed pressure relief valve port between valve element and valve pocket；
The two-position three-way valve has A1 hydraulic fluid ports, A2 hydraulic fluid ports, A3 hydraulic fluid ports, and two position four-way valve has B1 hydraulic fluid ports, B2 hydraulic fluid ports, B3
Hydraulic fluid port, B4 hydraulic fluid ports；
The A2 hydraulic fluid ports and B2 hydraulic fluid ports are to be used for and the loop-coupled fuel tank circuit interface of fuel tank；The A1 hydraulic fluid ports and B1 hydraulic fluid ports
It is connected with P1 hydraulic fluid ports；The hydraulic control end of two-position three-way valve and two position four-way valves connects with guide's hydraulic fluid port (P10)；A3 hydraulic fluid ports and C1
Chamber connects, and B4 hydraulic fluid ports connect with C3 chambers and C5 chambers simultaneously, and B3 hydraulic fluid ports connect with C2 chambers；Pressure signal delivery outlet (LSO) at the same with
C2 chambers connect with C4 chambers, and pressure signal input port (LSI) connects with C6 chambers；
When guide's hydraulic fluid port has effective pilot pressure signal input, A1 hydraulic fluid ports turn on A3 hydraulic fluid ports, and B1 hydraulic fluid ports turn on B4 hydraulic fluid ports,
B3 hydraulic fluid ports connect through damping hole with B2 hydraulic fluid ports；When guide's hydraulic fluid port does not have effective pilot pressure signal input, A3 hydraulic fluid ports and A2 hydraulic fluid ports
Conducting, B2 hydraulic fluid ports turn on B3 hydraulic fluid ports and B4 hydraulic fluid ports simultaneously.
2. load simulation valve according to claim 1, it is characterised in that the C6 intracavitary is provided with back-moving spring.
3. a kind of loading machine variable system, including steering hydraulic system and hydraulic system of working；
The hydraulic steering system includes steering cylinder, is connected with steering cylinder and controls the flexible steering gear of steering cylinder, be excellent
The steering of pressure-gradient control valve, pumping hole and pressure-gradient control valve work oil inlet connection that first oil-feed port (CF) is connected with steering gear work oil inlet becomes
Amount pump, the hydraulic oil container being connected with steering variable pump oil inlet；
The hydraulic system of working includes boom cylinder and rotary ink tank, is connected with boom cylinder and rotary ink tank and controls swing arm
What oil cylinder and rotary ink tank stretched closes the uncompensated distributing valve of middle position, the pilot valve being connected with distributing valve, pumping hole and distributing valve work
The operating variable pump that oil inlet is connected and oil inlet is connected with hydraulic oil container；
The flow more than needed interflow oil-out of the pressure-gradient control valve is connected with the work oil inlet of the distributing valve；
Characterized by further comprising the load simulation valve described in shuttle valve, shuttle valve group (10) and two claims 1 or 2, two
Described load simulation valve is respectively the first load simulation valve (8) and the second load simulation valve (9)；
After the connection of the load signal delivery outlet of the steering pressure signal output of the steering gear and pressure-gradient control valve with the shuttle valve
The pressure signal delivery outlet (LSO) of one oil inlet connection, another oil inlet of the shuttle valve and the first load simulation valve 8 is even
Connect, the oil-out of the shuttle valve is connected with the load feedback mouth of steering variable pump；
The connection corresponding with each oil inlet of shuttle valve group of each guide's oil circuit of the pilot valve, the oil-out of shuttle valve group is simultaneously with first
Guide's hydraulic fluid port (P10) of load simulation valve and the second load simulation valve connects, and the P1 hydraulic fluid ports of the first load simulation valve become with turning to
The pumping hole connection of pump is measured, the P1 hydraulic fluid ports of the second load simulation valve are connected with the pumping hole of operating variable pump；The load of the distributing valve
Pressure output (LS5) at the same with the pressure signal input port of the first load simulation valve (8) and the second load simulation valve (9)
(LSI) connect；The pressure signal delivery outlet (LSO) of second load simulation valve (9) and the load feedback mouth (LS7) of operating variable pump
Connection.
4. loading machine variable system according to claim 3, it is characterised in that also including guide's delivery valve (16), the elder generation
The oil inlet for leading delivery valve is connected with the pumping hole of steering variable pump, the oil-out of guide's delivery valve and the guide oil of pilot valve
Source oil inlet connection.
5. loading machine variable system according to claim 4, it is characterised in that oil inlet and steering in guide's delivery valve
Guide's oily filter (12) is provided with connection oil circuit between variable pump pumping hole.
6. loading machine variable system according to claim 4, it is characterised in that oil-out and guide in guide's delivery valve
Guide check valve (15) is provided with connection oil circuit between the pilot control oil inlet of valve.
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| CN201711102334.XA CN107882798B (en) | 2017-11-10 | 2017-11-10 | Load simulation valve and loading machine variable system |
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| CN201711102334.XA CN107882798B (en) | 2017-11-10 | 2017-11-10 | Load simulation valve and loading machine variable system |
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| CN107905288A (en) * | 2017-11-01 | 2018-04-13 | 广西柳工机械股份有限公司 | Loading machine double speed steering control system |
| CN108644169A (en) * | 2018-05-31 | 2018-10-12 | 中航力源液压股份有限公司 | The high pressure automatic control device of integrated preferential velocity's control |
| CN109268332A (en) * | 2018-11-15 | 2019-01-25 | 广西柳工机械股份有限公司 | High-low pressure unloading valve and loader hydraulic system |
| CN109649481A (en) * | 2019-01-03 | 2019-04-19 | 扬州盛达特种车有限公司 | A kind of automobile energy-saving fluid-link steering auxiliary system |
| CN110206774A (en) * | 2019-06-19 | 2019-09-06 | 烟台华特液压机械有限公司 | It is a kind of for increasing the valve of excavator hydraulic distributing valve oil circuit |
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| CN109649481A (en) * | 2019-01-03 | 2019-04-19 | 扬州盛达特种车有限公司 | A kind of automobile energy-saving fluid-link steering auxiliary system |
| CN110206774A (en) * | 2019-06-19 | 2019-09-06 | 烟台华特液压机械有限公司 | It is a kind of for increasing the valve of excavator hydraulic distributing valve oil circuit |
| CN110206774B (en) * | 2019-06-19 | 2024-02-23 | 烟台华特液压机械有限公司 | Valve for increasing oil way of hydraulic distribution valve of excavator |
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