CN106151135A - A kind of concrete pumping hydraulic control system and concrete pumping machinery - Google Patents
A kind of concrete pumping hydraulic control system and concrete pumping machinery Download PDFInfo
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- CN106151135A CN106151135A CN201510204341.5A CN201510204341A CN106151135A CN 106151135 A CN106151135 A CN 106151135A CN 201510204341 A CN201510204341 A CN 201510204341A CN 106151135 A CN106151135 A CN 106151135A
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Abstract
The present invention relates to technical field of engineering machinery, open a kind of concrete pumping hydraulic control system and concrete pumping machinery, concrete pumping hydraulic control system includes enclosed pump assembly, the first pumping oil cylinder, the second pumping oil cylinder, enclosed pump assembly includes the second oil-out of the rodless cavity connection of the first oil-out and the second pumping oil cylinder connected with the rodless cavity of the first pumping oil cylinder, the rod chamber of the first pumping oil cylinder and the rod chamber connection of the second pumping oil cylinder；Also include: be arranged at the control valve on oil circuit between the rod chamber of the first pumping oil cylinder and the rod chamber of the second pumping oil cylinder；Control assembly, pumps the support load information of oil cylinder, to control enclosed pump assembly to the rodless cavity pumps hydraulic oil being in the pumping oil cylinder supporting load condition for obtaining the first pumping oil cylinder and second when concrete pumping machinery is shut down.Above-mentioned concrete pumping hydraulic control system can be shut down in time, and safety is higher, and then improves the stability of concrete pumping machinery.
Description
Technical field
The present invention relates to technical field of engineering machinery, particularly to a kind of concrete pumping hydraulic control system and
Concrete pumping machinery.
Background technology
Concrete pumping hydraulic control system applies to the control system of concrete pumping machinery, is applied to height
In the constructions such as layer pours；In concrete pumping hydraulic system, how to solve concrete pumping hydraulic control system
That unites waits that the problem expecting to slip cylinder is the emphasis that those skilled in the art need to consider in the design process.
Wait expect to slip cylinder refer to concrete pumping hydraulic system the clout carrying in pipe in time expecting because of deadweight backflow,
So that the phenomenon that the expansion link of the pumping oil cylinder in concrete pumping equipment bounces back.
At present, concrete pumping hydraulic system generally comprise have the enclosed pump assembly of two oil-outs, first
Pumping oil cylinder, the second pumping oil cylinder and distribution tilt cylinder, the rodless cavity of the first pumping oil cylinder and enclosed pump assembly
The connection of oil-out, the rodless cavity of the second pumping oil cylinder is with another oil-out of enclosed pump assembly even
Logical, the rod chamber of the first pumping oil cylinder and the second pumping oil cylinder is interconnected；Those skilled in the art are in design
Treat during concrete pumping hydraulic system and wait that the solution expecting to slip cylinder is all at enclosed pump assembly and wherein
Two-way plug-in valve is installed additional, when concrete pumping hydraulic system is in time expecting on oil-feed oil circuit between individual pumping oil cylinder
Need to close above-mentioned two-way plug-in valve, and then block the oil-feed oil between enclosed pump assembly and this pumping oil cylinder
Road, thus lock this pumping oil cylinder.
As a example by two-way plug-in valve is installed on the oil circuit between enclosed pump assembly and the first pumping oil cylinder, above-mentioned
In solution, when concrete pumping hydraulic system is in time expecting, distribution tilt cylinder need to swing back the first pumping oil all the time
Cylinder side so that locking first pumping oil cylinder carry load, i.e. when concrete pumping machinery is shut down by
During the second pumping oil cylinder carry load, concrete pumping hydraulic system still needs to action so that distribution tilt cylinder needs all the time
Swing back the first pumping oil cylinder side, have certain potential safety hazard, cause the less stable of concrete pumping machinery.
Summary of the invention
The invention provides a kind of concrete pumping hydraulic control system and concrete pumping machinery, this concrete
When hydraulic system operation searched by pump, safety is higher, and then improves the stability of concrete pumping machinery.
For reaching above-mentioned purpose, the present invention provides techniques below scheme:
A kind of concrete pumping hydraulic control system, including enclosed pump assembly, the first pumping oil cylinder, the second pump
Send oil cylinder, described enclosed pump assembly include the first oil-out that connects of rodless cavity with the first pumping oil cylinder and
Second oil-out of the rodless cavity connection of the second pumping oil cylinder, the rod chamber of described first pumping oil cylinder is with described
Connected by oil circuit between the rod chamber of the second pumping oil cylinder；Also include:
It is arranged at oil between the rod chamber of described first pumping oil cylinder and the rod chamber of described second pumping oil cylinder
Control valve on road；Described control valve disconnect when being in the first station described first pumping oil cylinder rod chamber with
Oil circuit between the rod chamber of described second pumping oil cylinder, connects described first pumping oil when being in the second station
Oil circuit between rod chamber and the rod chamber of described second pumping oil cylinder of cylinder；
Control assembly, be connected with described enclosed pump component signals, for obtaining when concrete pumping machinery is shut down
Take described first pumping oil cylinder and second and pump the support load information of oil cylinder, to control described enclosed pump assembly
The rodless cavity pump of the pumping oil cylinder supporting load condition it is in the first pumping oil cylinder and the second pumping oil cylinder
Liquor charging force feed.
In above-mentioned concrete pumping hydraulic control system, when the process of concrete pumping machinery pump concrete
In, regulate above-mentioned control valve to the second station, and then, concrete pump searches the first pumping oil cylinder of hydraulic system
Rod chamber and second pumping oil cylinder rod chamber between oil communication, enclosed pump assembly can control first
Pumping oil cylinder and the second pumping cylinder action carry out concrete pumping work；Shut down when concrete pumping machinery and treat
During material, regulating above-mentioned control valve and be in the first station, now, control valve is by the rod chamber of the first pumping oil cylinder
And second pumping oil cylinder rod chamber between oil circuit disconnect so that first pumping cylinder rod chamber in oil
Oil mass in amount and the second pumping cylinder rod chamber no longer changes；Meanwhile, concrete pumping machinery shuts down it
The duty of front enclosed pump assembly just makes a pumping in the first pumping oil cylinder and the second pumping oil cylinder
Oil cylinder is in the state supporting load, and control assembly can obtain the first pumping oil cylinder and second and pump oil cylinder
Support load information, with control enclosed pump assembly to first pumping oil cylinder and second pumping oil cylinder in be in support
The rodless cavity pumps hydraulic oil of the pumping oil cylinder of load condition, and then make concrete pumping machinery treat material process
In first pumping oil cylinder and second pumping oil cylinder in be in support load state pumping oil cylinder rodless cavity
Maintain certain pressure, so that being in the pumping oil cylinder locking of the state supporting load, wherein:
When the first pumping oil cylinder is in the state supporting load, enclosed pump assembly works on, and makes and first
The oil pressure of the first oil-out of the rodless cavity connection of pumping oil cylinder maintains certain pressure, now, the first pumping
In oil cylinder, the oil pressure in rodless cavity and the oil pressure in rod chamber are used for supporting load, and due to the first pumping oil cylinder
Rod chamber and second pumping oil cylinder rod chamber between oil circuit cut off by control valve, first pumping oil cylinder quilt
Locking.
When the second pumping oil cylinder is in support load condition, enclosed pump assembly works on, and makes and the second pump
The oil pressure sending the second oil-out that the rodless cavity of oil cylinder connects maintains certain pressure, now, the second pumping oil
In cylinder, the oil pressure in rodless cavity and the oil pressure in rod chamber are used for supporting load, and due to the second pumping oil cylinder
Oil circuit between the rod chamber of rod chamber and the first pumping oil cylinder is cut off by control valve, and the second pumping oil cylinder is locked
Only.
Therefore, above-mentioned concrete pumping hydraulic control system is in when material state, either the first pumping oil
Cylinder is in support load condition or the second pumping oil cylinder is in support load condition, concrete pumping hydraulic pressure control
System processed all can be shut down in time, and safety is higher, and then improves the stability of concrete pumping machinery.
Preferably, described enclosed pump assembly includes servo valve, main pump and main pump aperture oil cylinder；Servo valve
It is connected with controlling component signals, and described servo valve is connected with main pump aperture oil cylinder to control described by oil circuit
The oil-feed of main pump aperture oil cylinder and/or oil return, the piston rod of described main pump aperture oil cylinder is connected also with described main pump
Control main pump delivery and gyratory directions, described control assembly according to concrete pumping machinery before shutdown one
The electric support load described with power failure state acquisition that obtain of the automatically controlled end at the described servo valve two ends in the individual cycle is believed
Breath.
Preferably, described enclosed pump assembly also includes slippage pump and flushing valve；Wherein:
First hydraulic fluid port of described main pump connects with described first oil-out, the second hydraulic fluid port and described second oil-out
Connection；
The inlet port of described slippage pump connects with fuel tank, oil-out connect with the first hydraulic fluid port of described main pump and
Connect with the second hydraulic fluid port of described main pump, and the first hydraulic fluid port of the oil-out of described slippage pump and described main pump it
Between pipeline be provided with the check valve of the oil-out the first hydraulic fluid port towards described main pump, and described slippage pump is fuel-displaced
Between mouth and the second hydraulic fluid port of described main pump, pipeline is provided with the oil-out the second hydraulic fluid port towards described main pump
The first overflow valve it is provided with at check valve, and the oil-out of described slippage pump；
Described flushing valve includes that spool and valve body, described valve body have first connected with described first oil-out
The 3rd hydraulic fluid port that the second hydraulic fluid port that hydraulic fluid port connects with described second oil-out connects with fuel tank；Wherein, when
When the oil pressure of described first oil-out is more than the oil pressure of the second oil-out, described flushing valve is in the first work shape
State, the second hydraulic fluid port of described flushing valve connects with described 3rd hydraulic fluid port；When the oil pressure of described second oil-out is big
When the oil pressure of the first oil-out, described flushing valve is in the second duty, the first oil of described flushing valve
Mouth connects with described 3rd hydraulic fluid port；
Described servo valve has that the first hydraulic fluid port that the oil-out with described slippage pump connects connects with fuel tank
The 3rd hydraulic fluid port that two hydraulic fluid ports connect with described main pump aperture oil cylinder one end and described main pump aperture oil cylinder another
4th hydraulic fluid port of end connection；When described servo valve is in the first duty, the first oil of described servo valve
Mouth connects with the 3rd hydraulic fluid port, the second hydraulic fluid port and the connection of the 4th hydraulic fluid port；When described servo valve is in the second work shape
During state, the first hydraulic fluid port of described servo valve and the connection of the 4th hydraulic fluid port, the second hydraulic fluid port and the connection of the 3rd hydraulic fluid port；When
When described servo valve is in three duties, the first hydraulic fluid port of described servo valve, the second hydraulic fluid port, the 3rd oil
It is interconnected between mouth and the 4th hydraulic fluid port；Described servo valve passes through being switched between three kinds of duties
And control described main pump aperture oil cylinder and regulate described main pump delivery and gyratory directions.
Preferably, described flushing valve also includes:
The first oil pocket between described spool and described valve body, between described spool and described valve body
The second oil pocket；Described first oil pocket connects with described first oil-out, described second oil pocket and described second
Oil-out connects, and promotes described spool when the oil pressure of described first oil pocket is more than the oil pressure of described second oil pocket
It is in the first duty to the second oil pocket Slideslip to described flushing valve；When the oil pressure of described second oil pocket is big
When the oil pressure of the first oil pocket, in described second oil pocket, oil pressure promotes described spool to break away to described first oil pocket
Move to described flushing valve and be in the second duty.
Preferably, also include:
Shuttle valve, the first oil-in of described shuttle valve connects with described first oil-out, and the second of described shuttle valve enters
Hydraulic fluid port connects with described second oil-out；
It is arranged at the oil-out of described shuttle valve for gathering described first oil-out and described second oil-out
Between the pressure transducer of oil pressure of the bigger oil-out of oil pressure, described pressure transducer and described control assembly
Between signal connect, described control assembly controls institute for the pressure information gathered according to described pressure transducer
State the aperture of servo valve so that main pump delivery meets system load demand.
Preferably, also include:
Being arranged at the return line between oil-out and the fuel tank of described shuttle valve, described pressure transducer is arranged at
On described return line；
It is arranged at described return line and the second overflow between described pressure transducer and described fuel tank
Valve；
It is arranged on return line and hydraulic control between described second overflow valve and described pressure transducer
Check valve, and described hydraulic control one-way valve is closed, when described control valve when described control valve is in the second station
It is in described hydraulic control one-way valve during the first station to open.
Preferably, the pipeline between described second overflow valve and fuel tank is provided with radiator.
Preferably, the pipeline between oil-out and described second overflow valve and the described radiator of described flushing valve
Connection.
Preferably, described control valve is two-way plug-in valve.
Preferably, described hydraulic control system also includes that reversal valve, described reversal valve have and connects with oil sources
The second hydraulic fluid port that first hydraulic fluid port connects with the oil-in of described two-way plug-in valve connect with described fuel tank
Three hydraulic fluid ports, when described reversal valve is in the first duty, the first hydraulic fluid port of described reversal valve and the second oil
Mouth connection, when described reversal valve is in the second duty, the 3rd hydraulic fluid port of described reversal valve and the second oil
Mouth connection.
Preferably, the second overflow valve and hydraulic control one-way valve are included when described concrete pumping hydraulic control system
Time, the first guide cavity of described hydraulic control one-way valve connects with the second hydraulic fluid port of described reversal valve.
Present invention also offers a kind of concrete pumping machinery, this concrete pumping machinery includes above-mentioned technical side
Any one the concrete pumping hydraulic control system provided in case.
Accompanying drawing explanation
The oil circuit schematic diagram of the concrete pumping hydraulic control system that Fig. 1 provides for the present invention.
Detailed description of the invention
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clearly
Chu, be fully described by, it is clear that described embodiment be only a part of embodiment of the present invention rather than
Whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art are not making creation
The every other embodiment obtained under property work premise, broadly falls into the scope of protection of the invention.
Refer to Fig. 1, wherein, the oil circuit of the concrete pumping hydraulic control system that Fig. 1 provides for the present invention
Schematic diagram.
As it is shown in figure 1, the concrete pumping hydraulic control system that the embodiment of the present invention provides includes enclosed pump group
Part 1, first pumps oil cylinder 2, second and pumps oil cylinder 3, and enclosed pump assembly 1 includes and the first pumping oil cylinder 2
Rodless cavity 21 connection the first oil-out A and second pumping oil cylinder 3 rodless cavity 31 connection second
Oil-out B is logical between rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3 of the first pumping oil cylinder 2
Cross oil circuit to connect；Above-mentioned concrete pumping hydraulic control system also includes:
It is arranged at oil between rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3 of the first pumping oil cylinder 2
Control valve 4 on road, described control valve 4 includes the first station and the second station, and control valve 4 is in first
During station, what control valve 4 disconnected the rod chamber 22 of the first pumping oil cylinder 2 and the second pumping oil cylinder 3 has bar
Oil circuit between chamber 32, when control valve 4 is in the second station, control valve 4 connects the first pumping oil cylinder 2
Rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3 between oil circuit；
Control assembly, be connected with described enclosed pump component signals, for obtaining when concrete pumping machinery is shut down
Take described first pumping oil cylinder 2 and second and pump the support load information of oil cylinder 3, to control described enclosed pump
Assembly is in the nothing of the pumping oil cylinder supporting load condition in the first pumping oil cylinder 2 and the second pumping oil cylinder 3
Bar chamber pumps hydraulic oil.
Described load information includes pumping whether oil cylinder is in support load condition.Described support load condition refers to
Be when concrete pumping machinery is shut down, the concrete cylinder of pumping oil cylinder and concrete pumping machinery and S pipe,
Concrete conveyance pipeline connects, and now, the concrete in concrete delivery pipe is under gravity to pumping oil
The piston of cylinder produces certain pressure, and pumping oil cylinder now is i.e. in load condition.
It should be noted that the time of above-mentioned " when concrete pumping machinery is shut down " can be concrete pump
While sending machinery to stop pumping, it is also possible to be the certain time after concrete pumping machinery is shut down.
In above-mentioned concrete pumping hydraulic control system, when the process of concrete pumping machinery pump concrete
In, regulate above-mentioned control valve 4 and be in the second station, and then, the first of concrete pumping hydraulic control system
Oil communication between rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3 of pumping oil cylinder 2, enclosed
Pump assembly 1 can control the first pumping oil cylinder 2 and the second pumping oil cylinder 3 action carries out concrete pumping work；
When concrete pumping machinery is shut down in time expecting, regulate above-mentioned control valve 4 and be in the first station, now, control
Valve 4 is by the oil circuit between rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3 of the first pumping oil cylinder 2
Disconnect；Meanwhile, before concrete pumping machinery is shut down, the duty of enclosed pump assembly 1 just makes the first pump
Send a pumping oil cylinder in oil cylinder 2 and the second pumping oil cylinder 3 to be in the state supporting load, control assembly
The first pumping oil cylinder 2 and second can be obtained and pump the support load information of oil cylinder 3, to control enclosed pump group
Part 1 is in the nothing of the pumping oil cylinder supporting load condition in the first pumping oil cylinder 2 and the second pumping oil cylinder 3
Bar chamber pumps hydraulic oil, and then make concrete pumping machinery first pumping oil cylinder 2 and second during waiting to expect
The rodless cavity of the pumping oil cylinder being in the state supporting load in pumping oil cylinder 3 maintains certain pressure, so that
It is in the pumping oil cylinder locking of the state supporting load, wherein:
When the first pumping oil cylinder 2 is in support load condition, as shown in fig. 1, enclosed pump assembly 1 continues
Continuous work, makes the oil pressure of the first oil-out A connected with the rodless cavity 21 of the first pumping oil cylinder 2 maintain one
Fixed pressure, now, the oil pressure in the first pumping oil cylinder 2 rodless cavity 21 is to support load, and due to the
Oil circuit between rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3 of one pumping oil cylinder 2 is by control valve
4 cut off, and the first pumping oil cylinder 2 is locked out.
In like manner, when the second pumping oil cylinder 3 is in support load condition, enclosed pump assembly 1 works on,
The oil pressure making the second oil-out B connected with the rodless cavity 31 of the second pumping oil cylinder 3 maintains certain pressure,
Now, the oil pressure in the second pumping oil cylinder 3 rodless cavity 31 can support load, and due to the second pumping oil
Oil circuit between rod chamber 32 and the rod chamber 22 of the first pumping oil cylinder 2 of cylinder 3 is cut off by control valve 4,
Second pumping oil cylinder 3 is locked out.
Therefore, above-mentioned concrete pumping hydraulic control system is in when material state, either the first pumping oil
Cylinder 2 is in support load condition or the second pumping oil cylinder 3 is in support load condition, concrete pump liquor charging
Pressure control system all can be shut down in time, and safety is higher, and then improves the stability of concrete pumping machinery.
Further, enclosed pump assembly 1 includes servo valve 15, main pump 11 and main pump aperture oil cylinder 16,
Servo valve 15 is connected with controlling component signals, and described servo valve 15 is by oil circuit and main pump aperture oil cylinder 16
Connect, for controlling oil-feed and/or the oil return of described main pump aperture oil cylinder 16, described main pump aperture oil cylinder 16
For controlling discharge capacity and the gyratory directions of main pump 11.Described servo valve 15 includes the first automatically controlled end and second
Automatically controlled end, when the first automatically controlled end obtains electric, the left chamber (left side of Fig. 1) of described main pump aperture oil cylinder 16
Oil-feed, now, described main pump aperture oil cylinder 16 controls main pump to the first oil-out A fuel feeding, and control into
The fluid amount in the left chamber entering described main pump aperture oil cylinder 16 can control the discharge capacity of main pump 11.When second is automatically controlled
When holding electric, left chamber (right side of Fig. 1) oil-feed of described main pump aperture oil cylinder 16, now, described master
Pump aperture oil cylinder 16 controls main pump 11 to the second oil-out B fuel feeding.Therefore, only servo valve 15 need to be judged
Automatically controlled end electric and power failure state can judge which main pump 11 pump oil cylinder pumps hydraulic oil to.
Therefore, in the present embodiment, controlling assembly can be according to servo valve 15 before concrete pumping machinery is shut down
The electric first pumping oil cylinder 2 and second described with power failure state acquisition that obtain of the automatically controlled end in the individual cycle pumps oil cylinder
The support load information of 3.Such as, in the cycle before shutting down at concrete pumping machinery, servo valve
When the first automatically controlled end of 15 obtains electric and the second automatically controlled end dead electricity, in showing to shut down the previous cycle, main pump is to first
Pumping oil cylinder 2 pumps hydraulic oil, when shutting down, described first pumping oil cylinder 2 is i.e. in load condition, with
Reason can draw when the second automatically controlled end of servo valve 15 obtains electric and the first automatically controlled end dead electricity, described second pumping oil
Cylinder 3 is i.e. in load condition.
Specifically, as it is shown in figure 1, enclosed pump assembly 1 also includes, slippage pump 12, flushing valve 10；Its
In:
First hydraulic fluid port of main pump 11 and the first oil-out A connection, the second hydraulic fluid port and the second oil-out B connection；
The inlet port of slippage pump 12 connects with fuel tank, oil-out connect with the first hydraulic fluid port of main pump 11 and with
Second hydraulic fluid port connection of main pump 11, and manage between the oil-out of slippage pump 12 and the first hydraulic fluid port of main pump 11
Road is provided with the check valve 14 of the oil-out the first hydraulic fluid port towards main pump 11, and the oil-out of slippage pump 12 with
Between second hydraulic fluid port of main pump 11, pipeline is provided with the check valve of the oil-out the second hydraulic fluid port towards main pump 11
13；And at the oil-out of slippage pump 12, it is provided with the first overflow valve 17；
Flushing valve 10 includes spool and valve body, valve body have connect with the first oil-out A the first hydraulic fluid port,
The 3rd hydraulic fluid port that the second hydraulic fluid port connected with the second oil-out B connects with fuel tank；Wherein, fuel-displaced when first
When the oil pressure of mouth A is more than the oil pressure of the second oil-out B, flushing valve 10 is in the first duty, rinses
Second hydraulic fluid port of valve 10 and the connection of the 3rd hydraulic fluid port；When the oil pressure of the second oil-out B is more than the first oil-out A
Oil pressure time, flushing valve 10 is in the second duty, and the first hydraulic fluid port of flushing valve 10 and the 3rd hydraulic fluid port are even
Logical；
Servo valve 15 has second that the first hydraulic fluid port that the oil-out with slippage pump 12 connects connects with fuel tank
The 3rd hydraulic fluid port that hydraulic fluid port connects with main pump aperture oil cylinder 16 1 cavity and another chamber of main pump aperture oil cylinder 16
4th hydraulic fluid port of body connection；When servo valve 15 is in the first duty (the first automatically controlled end obtains electric,
Second automatically controlled end dead electricity), the first hydraulic fluid port of servo valve 15 and the connection of the 3rd hydraulic fluid port, the second hydraulic fluid port and the 4th oil
Mouth connection；When servo valve 15 is in the second duty, (the second automatically controlled end obtains electric, the first automatically controlled end
Dead electricity), the first hydraulic fluid port of servo valve 15 and the connection of the 4th hydraulic fluid port, the second hydraulic fluid port and the connection of the 3rd hydraulic fluid port；When
When servo valve 15 is in three duties (the second automatically controlled end and the first equal dead electricity of automatically controlled end), servo valve 15
The first hydraulic fluid port, the second hydraulic fluid port, be interconnected between the 3rd hydraulic fluid port and the 4th hydraulic fluid port；Servo valve 15 leads to
The switching crossed between three kinds of duties regulates the angle of swash plate in main pump 11 by main pump aperture oil cylinder 16
Degree, and then the discharge capacity of regulation main pump 11, make the discharge capacity of main pump 11 meet in system and be in support load condition
Pumping oil cylinder rodless cavity in the demand of oil pressure.
In the enclosed pump assembly of said structure, servo valve 15 can regulate by controlling main pump aperture oil cylinder 16
The angle of swash plate in main pump 11, therefore, concrete pumping machinery shuts down the work of servo valve 15 before waiting to expect
State can reflect the enclosed pump assembly 1 duty before concrete pumping machinery is shut down, and such as closes
The direction of rotation of formula pump assembly 1 and discharge capacity, therefore, control assembly be connected with servo valve 15 signal and
The duty of servo valve 15 in the cycle waited before expecting can be shut down according to concrete pumping machinery
Judge the duty of enclosed pump assembly 1, and, control assembly by making servo valve 15 maintain coagulation
The duty in the cycle before soil pumping machine shutdown can make enclosed pump assembly 1 maintain coagulation
Duty before soil pumping machine shutdown.
It should be noted that described " cycle " refers to concrete cylinder carries out suction of continuous print or discharging
Process, this process correspondence pumps the retraction of the piston rod of oil cylinder or stretches out process.
Meanwhile, in the enclosed pump assembly of said structure, either the oil pressure of the first oil-out A goes out more than second
The oil pressure of hydraulic fluid port B or the oil pressure of the second oil-out B oil pressure more than the first oil-out A, as long as the
Oil pressure between one oil-out A and the second oil-out B there are differences, and flushing valve 10 can by oil pressure relatively
High temperature oil in a low lateral line puts back to fuel tank, simultaneously by slippage pump 12 to the relatively low lateral line of oil pressure
In supplement cold oil, and then can in time enclosed pump assembly 1 be lowered the temperature.
More specifically, in order to improve flushing valve 10 according to oil between the first oil-out A and the second oil-out B
Change the regulating the speed between two kinds of duties of pressure relation, above-mentioned flushing valve 10 also includes:
The first oil pocket between spool and valve body, the second oil pocket between spool and valve body；First
Oil pocket and the first oil-out A connection, the second oil pocket and the second oil-out B connection, when the oil of the first oil pocket
Spool is promoted to be in the first work to the second oil pocket Slideslip to flushing valve 10 when pressure is more than the oil pressure of the second oil pocket
Make state；When the oil pressure of the second oil pocket is more than the oil pressure of the first oil pocket, in the second oil pocket, oil pressure promotes spool
It is in the second duty to flushing valve 10 to the first oil pocket Slideslip.
The flushing valve 10 of said structure can be closed according to oil pressure between the first oil-out A and the second oil-out B
The change of system adjusts between two kinds of duties automatically, and then can improve flushing valve 10 and go out according to first
The speed that between hydraulic fluid port A and the second oil-out B, the change of oil pressure relation adjusts between two kinds of duties.
Specifically, in order to reduce the main pump 11 output under treating material state in enclosed pump assembly 1, on
State concrete pumping hydraulic control system and also include shuttle valve 8 and pressure transducer 18；
Wherein, the first oil-in of shuttle valve 8 and the first oil-out A connection, the second oil-in and second fuel-displaced
Mouth B connection；
Pressure transducer 18 connects with the oil-out of shuttle valve 8, and pressure transducer 18 with control component signals
Connect, control assembly and control the aperture of servo valve 15 for the pressure information gathered according to pressure transducer 18,
And then make the angle of swash plate in main pump 11, so that the discharge capacity of main pump 11 meets system load demand, i.e. can
Maintain the force value required for system load.Specifically, the pressure collected is sent by pressure transducer 18
To controlling assembly, control assembly and this force value is generated corresponding control electric current to servo valve 15 to control master
The discharge capacity of pump 11.
Preferably, anti-to main pump in enclosed pump assembly in order to reduce in above-mentioned concrete pumping hydraulic control system
The requirement of sensitivity, above-mentioned concrete pumping hydraulic control system is answered also to include:
Being arranged at the return line between oil-out and the fuel tank of shuttle valve 8, pressure transducer 18 is arranged at back
On oil pipe line；
It is arranged at return line and the second overflow valve 5 between pressure transducer 18 and fuel tank；
It is arranged on return line and fluid-control one-way between the second overflow valve 5 and pressure transducer 18
Valve 6, and hydraulic control one-way valve 6 is closed, is in first when control valve 4 when control valve 4 is in the second station
During station, hydraulic control one-way valve 6 is opened.
When the first pumping oil cylinder 2 is in the state supporting load, as shown in fig. 1, with the first pumping oil
The oil pressure of the first oil-out A of rodless cavity 21 connection of cylinder 2 is more than the rodless cavity with the second pumping oil cylinder 3
The oil pressure of the second oil-out B of 31 connections, now, first connected with the first oil-out A in shuttle valve 8
Oil-in is opened, and the second oil-in that shuttle valve 8 connects with the second oil-out B simultaneously is closed, and, due to
Hydraulic control one-way valve 6 between oil-out and second overflow valve 5 of shuttle valve 8 is in opening, therefore, with
The oil pressure relief value that the pressure of the return line of shuttle valve 8 connection is set by the second overflow valve 5 controls, in theory,
This oil pressure relief value is equal to the oil pressure at shuttle valve 8 oil-out, meanwhile, the oil pressure at the first oil-out A and shuttle
Oil pressure at valve 8 oil-out is essentially identical, and the oil pressure and first in the first pumping oil cylinder 2 rodless cavity 21
Oil pressure at oil-out A is identical, thus pressure transducer 18 detect force value reflection be the first pump
Send the oil pressure in oil cylinder 2 rodless cavity 21, therefore, as long as the second overflow valve 5 is set suitable overflow pressure
Force value (such as, pumping stops the rodless cavity force value in previous cycle), pressure transducer 18 is in real time to control
Assembly feeds back its pressure collected so that main pump 11 constantly adjusts discharge capacity with by shuttle valve 8 oil-out
The oil that maintains in the OK range of described oil pressure relief value in the first pumping oil cylinder 2 rodless cavity 21 of pressure
Pressure may be used for supporting load, and owing to the rod chamber 22 and second of the first pumping oil cylinder 2 pumps oil cylinder 3
Rod chamber 32 between oil circuit cut off by control valve 4, first pumping oil cylinder 2 is locked out.
In like manner, when second pumping oil cylinder 3 be in support load condition time, with second pumping oil cylinder 3 without bar
The oil pressure of the second oil-out B of chamber 31 connection is more than the connected with the rodless cavity 21 of the first pumping oil cylinder 2
The oil pressure of one oil-out A, now, the second oil-in connected with the second oil-out B in shuttle valve 8 is opened,
The the first oil-in closedown simultaneously connect with the first oil-out A, and, due to the oil-out and the of shuttle valve 8
Hydraulic control one-way valve 6 between two overflow valves 5 is in opening, therefore, with the oil return pipe of shuttle valve 8 UNICOM
The oil pressure relief value that the pressure on road is set by the second overflow valve 5 controls, and in theory, this oil pressure relief value is equal to
Oil pressure at shuttle valve 8 oil-out, meanwhile, the oil pressure at the second oil-out B and the oil at shuttle valve 8 oil-out
Press essentially identical, so, the force value reflection that pressure transducer 18 detects is the second pumping oil cylinder 3
Oil pressure in rodless cavity 31, therefore, as long as setting suitable oil pressure relief value (ratio by the second overflow valve 5
As, pumping stops the rodless cavity force value in previous cycle), the oil pressure in the second pumping oil cylinder 3 rodless cavity 31
May be used for supporting load, and owing to the rod chamber 31 and first of the second pumping oil cylinder 3 pumps oil cylinder 2
Oil circuit between rod chamber 21 is cut off by control valve 4, and the second pumping oil cylinder 3 is locked out.
Second overflow valve 5 can arrange its minimum overflow force value according to operating mode, and main pump 11 transfers to be in and props up
First pumping oil cylinder 2 of support load condition or the oil pressure of the second pumping oil cylinder 3 disclosure satisfy that system load institute
The force value needed.
In a kind of preferred implementation, as it is shown in figure 1, set on the pipeline between the second overflow valve 5 and fuel tank
There is radiator 9.
Fluid in oil circuit by radiator 9 can be cooled down by radiator 9, thus reduces in system
The deep fat impact on fuel tank inner fluid temperature.
It is highly preferred that as it is shown in figure 1, when enclosed pump assembly 1 includes flushing valve 10, flushing valve 10
Pipeline connection between oil-out and the second overflow valve 5 and radiator 9.I.e. arranged by flushing valve 10 oil-out
The fluid gone out just enters in fuel tank after also passing through radiator 9 cooling, thus reduces intrasystem heat further
The oil impact on fuel tank inner fluid temperature.
On the basis of the respective embodiments described above, in a kind of embodiment, it is arranged at the first pumping oil cylinder 2
Between rod chamber 22 and the rod chamber 32 of the second pumping oil cylinder 3, the control valve 4 on oil circuit can be that two-way is inserted
Dress valve.
On the basis of the respective embodiments described above, in a kind of embodiment, as it is shown in figure 1, described hydraulic pressure control
System processed also includes:
Reversal valve 7, reversal valve 7 has the first hydraulic fluid port and the oil-in of two-way plug-in valve connected with oil sources
The 3rd hydraulic fluid port that second hydraulic fluid port of connection connects with fuel tank, when reversal valve 7 is in the first duty,
First hydraulic fluid port of reversal valve 7 and the connection of the second hydraulic fluid port, when reversal valve 7 is in the second duty, commutation
3rd hydraulic fluid port of valve 7 and the connection of the second hydraulic fluid port.
Preferably, above-mentioned reversal valve 7 can be two-position valve, it is also possible to for three-position valve, as shown in fig. 1,
Above-mentioned reversal valve is two-position three way magnetic valve.
Certainly, when concrete pumping hydraulic control system includes the second overflow valve 5 and hydraulic control one-way valve 6,
The first guide cavity of hydraulic control one-way valve 6 can connect with the second hydraulic fluid port of above-mentioned reversal valve 7.
Present invention also offers a kind of concrete pumping machinery, this concrete pumping machinery includes above-mentioned technical side
Any one the concrete pumping hydraulic control system provided in case.
Obviously, those skilled in the art can carry out various change and modification to the embodiment of the present invention and not take off
From the spirit and scope of the present invention.So, if these amendments of the present invention and modification belong to right of the present invention
Require and within the scope of equivalent technologies, then the present invention is also intended to comprise these change and modification.
Claims (12)
1. a concrete pumping hydraulic control system, including enclosed pump assembly, the first pumping oil cylinder, the
Two pumping oil cylinders, described enclosed pump assembly includes that connect with the rodless cavity of the first pumping oil cylinder first is fuel-displaced
The second oil-out that mouth connects with the rodless cavity of the second pumping oil cylinder, the rod chamber of described first pumping oil cylinder
And it is connected by oil circuit between the rod chamber of described second pumping oil cylinder；It is characterized in that, also include:
It is arranged at oil between the rod chamber of described first pumping oil cylinder and the rod chamber of described second pumping oil cylinder
Control valve on road；Described control valve disconnect when being in the first station described first pumping oil cylinder rod chamber with
Oil circuit between the rod chamber of described second pumping oil cylinder, when described control valve is in the second station, connection is described
Oil circuit between rod chamber and the rod chamber of described second pumping oil cylinder of the first pumping oil cylinder；
Control assembly, be connected with described enclosed pump component signals, for obtaining when concrete pumping machinery is shut down
Take described first pumping oil cylinder and second and pump the support load information of oil cylinder, to control described enclosed pump assembly
The rodless cavity pump of the pumping oil cylinder supporting load condition it is in the first pumping oil cylinder and the second pumping oil cylinder
Liquor charging force feed.
Concrete pumping hydraulic control system the most according to claim 1, it is characterised in that described
Enclosed pump assembly includes servo valve, main pump and main pump aperture oil cylinder；Servo valve connects with controlling component signals
Connect, and described servo valve is connected with main pump aperture oil cylinder to control entering of described main pump aperture oil cylinder by oil circuit
Oil and/or oil return, the piston rod of described main pump aperture oil cylinder be connected with described main pump and control main pump delivery and
Gyratory directions, described control assembly is watched according in concrete pumping machinery cycle before shutdown
Take valve two ends automatically controlled end electric and power failure state obtains described support load information.
Concrete pumping hydraulic control system the most according to claim 2, it is characterised in that described
Enclosed pump assembly also includes slippage pump and flushing valve；Wherein:
First hydraulic fluid port of described main pump connects with described first oil-out, the second hydraulic fluid port and described second oil-out
Connection；
The inlet port of described slippage pump connects with fuel tank, oil-out connect with the first hydraulic fluid port of described main pump and
Connect with the second hydraulic fluid port of described main pump, and the first hydraulic fluid port of the oil-out of described slippage pump and described main pump it
Between pipeline be provided with the check valve of the oil-out the first hydraulic fluid port towards described main pump, and described slippage pump is fuel-displaced
Between mouth and the second hydraulic fluid port of described main pump, pipeline is provided with the oil-out the second hydraulic fluid port towards described main pump
The first overflow valve it is provided with at check valve, and the oil-out of described slippage pump；
Described flushing valve includes that spool and valve body, described valve body have first connected with described first oil-out
The 3rd hydraulic fluid port that the second hydraulic fluid port that hydraulic fluid port connects with described second oil-out connects with fuel tank；Wherein, when
When the oil pressure of described first oil-out is more than the oil pressure of the second oil-out, described flushing valve is in the first work shape
State, the second hydraulic fluid port of described flushing valve connects with described 3rd hydraulic fluid port；When the oil pressure of described second oil-out is big
When the oil pressure of the first oil-out, described flushing valve is in the second duty, the first oil of described flushing valve
Mouth connects with described 3rd hydraulic fluid port；
Described servo valve has that the first hydraulic fluid port that the oil-out with described slippage pump connects connects with fuel tank
The 3rd hydraulic fluid port that two hydraulic fluid ports connect with described main pump aperture oil cylinder one end and described main pump aperture oil cylinder another
4th hydraulic fluid port of end connection；When described servo valve is in the first duty, the first oil of described servo valve
Mouth connects with the 3rd hydraulic fluid port, the second hydraulic fluid port and the connection of the 4th hydraulic fluid port；When described servo valve is in the second work shape
During state, the first hydraulic fluid port of described servo valve and the connection of the 4th hydraulic fluid port, the second hydraulic fluid port and the connection of the 3rd hydraulic fluid port；When
When described servo valve is in three duties, the first hydraulic fluid port of described servo valve, the second hydraulic fluid port, the 3rd oil
It is interconnected between mouth and the 4th hydraulic fluid port；Described servo valve passes through being switched between three kinds of duties
And control described main pump aperture oil cylinder and regulate described main pump delivery and gyratory directions.
Concrete pumping hydraulic control system the most according to claim 3, it is characterised in that described
Flushing valve also includes:
The first oil pocket between described spool and described valve body, between described spool and described valve body
The second oil pocket；Described first oil pocket connects with described first oil-out, described second oil pocket and described second
Oil-out connects, and promotes described spool when the oil pressure of described first oil pocket is more than the oil pressure of described second oil pocket
It is in the first duty to the second oil pocket Slideslip to described flushing valve；When the oil pressure of described second oil pocket is big
When the oil pressure of the first oil pocket, in described second oil pocket, oil pressure promotes described spool to break away to described first oil pocket
Move to described flushing valve and be in the second duty.
Concrete pumping hydraulic control system the most according to claim 2, it is characterised in that also wrap
Include:
Shuttle valve, the first oil-in of described shuttle valve connects with described first oil-out, and the second of described shuttle valve enters
Hydraulic fluid port connects with described second oil-out；
It is arranged at the oil-out of described shuttle valve for gathering described first oil-out and described second oil-out
Between the pressure transducer of oil pressure of the bigger oil-out of oil pressure, described pressure transducer and described control assembly
Between signal connect, described control assembly controls institute for the pressure information gathered according to described pressure transducer
State the aperture of servo valve so that main pump delivery meets system load demand.
Concrete pumping hydraulic control system the most according to claim 5, it is characterised in that also wrap
Include:
Being arranged at the return line between oil-out and the fuel tank of described shuttle valve, described pressure transducer is arranged at
On described return line；
It is arranged at described return line and the second overflow between described pressure transducer and described fuel tank
Valve；
It is arranged on return line and hydraulic control between described second overflow valve and described pressure transducer
Check valve, and described hydraulic control one-way valve is closed, when described control valve when described control valve is in the second station
It is in described hydraulic control one-way valve during the first station to open.
Concrete pumping hydraulic control system the most according to claim 6, it is characterised in that described
Pipeline between second overflow valve and fuel tank is provided with radiator.
Concrete pumping hydraulic control system the most according to claim 7, it is characterised in that described
Pipeline connection between oil-out and described second overflow valve and the described radiator of flushing valve.
9. according to the concrete pumping hydraulic control system described in claim 1-8, it is characterised in that institute
Stating control valve is two-way plug-in valve.
Concrete pumping hydraulic control system the most according to claim 8, it is characterised in that described
Hydraulic control system also includes that reversal valve, described reversal valve have the first hydraulic fluid port connected with oil sources with described
The 3rd hydraulic fluid port that second hydraulic fluid port of the oil-in connection of two-way plug-in valve connects with described fuel tank, changes when described
When valve is in the first duty, the first hydraulic fluid port of described reversal valve and the connection of the second hydraulic fluid port, change when described
When valve is in the second duty, the 3rd hydraulic fluid port of described reversal valve and the connection of the second hydraulic fluid port.
11. concrete pumping hydraulic control systems according to claim 9, it is characterised in that work as institute
State concrete pumping hydraulic control system when including the second overflow valve and hydraulic control one-way valve, described hydraulic control one-way valve
First guide cavity connect with the second hydraulic fluid port of described reversal valve.
12. 1 kinds of concrete pumping machineries, it is characterised in that include as described in any one of claim 1-11
Concrete pumping hydraulic control system.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510204341.5A CN106151135B (en) | 2015-04-27 | 2015-04-27 | A kind of concrete pumping hydraulic control system and concrete pumping machinery |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510204341.5A CN106151135B (en) | 2015-04-27 | 2015-04-27 | A kind of concrete pumping hydraulic control system and concrete pumping machinery |
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| CN106151135B CN106151135B (en) | 2018-09-28 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110131122A (en) * | 2019-03-29 | 2019-08-16 | 中联重科股份有限公司 | Prevent pumping system from slipping the control method, system and pumping installations of cylinder |
| CN111810474A (en) * | 2020-08-13 | 2020-10-23 | 四川新筑智能工程装备制造有限公司 | Wet spraying trolley pumping hydraulic control system |
| CN113227587A (en) * | 2018-12-26 | 2021-08-06 | 潍柴动力股份有限公司 | Hydraulic variable pump set and excavator |
| CN115324960A (en) * | 2022-07-25 | 2022-11-11 | 湖南中联重科智能高空作业机械有限公司 | Oil cylinder hydraulic system and overhead working machine |
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|---|---|
| CN106151135B (en) | 2018-09-28 |
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