CN104047912B - The digital pump controlled hydraulic differential cylinder in self-powered source - Google Patents
The digital pump controlled hydraulic differential cylinder in self-powered source Download PDFInfo
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- CN104047912B CN104047912B CN201410293460.8A CN201410293460A CN104047912B CN 104047912 B CN104047912 B CN 104047912B CN 201410293460 A CN201410293460 A CN 201410293460A CN 104047912 B CN104047912 B CN 104047912B
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Abstract
The invention discloses the digital pump controlled hydraulic differential cylinder in self-powered source, it comprises hydraulic pressure power unit oil hydraulic cylinder and hydraulic power parts power source, the structure of power source is: the oil inlet and outlet of the rod chamber of double-action differential hydro cylinder is by being connected with the first Pilot operated check valve in turn, an oil hydraulic motor in bidirectional shunt oil hydraulic motor, the fluid pipe-line of two-way quantitative oil hydraulic pump and the second Pilot operated check valve is connected with the filler opening that goes out of the rodless cavity of double-action differential hydro cylinder, a hydraulic port of another oil hydraulic motor in bidirectional shunt oil hydraulic motor is communicated with the fluid pipe-line between the oil hydraulic motor of in bidirectional shunt oil hydraulic motor and two-way quantitative oil hydraulic pump and another hydraulic port of another oil hydraulic motor is communicated with fuel tank by connecting line, the pump shaft of two-way quantitative oil hydraulic pump is connected with the motor shaft of motor.Adopt that this device can not leak, compact structure, without restriction loss.
Description
Technical field
The present invention relates to differential hydro cylinder, the invention particularly relates to a kind of pump control type hydraulic power unit of integrated self-powered source, belong to electrohydraulic control technology field and machinery manufacturing technology field.
Background technique
Electrohydraulic control system has volumetric void fraction and throttling to control two large classes.Throttling controls electrohydraulic system and mostly adopts selector valve, not only cannot bear the long-term requirement that commutates at a high speed, and restriction loss causes system heating excessive, causes energy dissipation.New developing direction is with the direct hydraulic control cylinder of oil hydraulic pump.In hydraulics, the final controlling element of extensive use is the differential hydro cylinder of singly lifting one's head.Differential hydro cylinder due to rod chamber and rodless cavity area not etc., like this as still continued to use the circuit theory controlling uniform section cylinder, system just cannot normally work, and makes the difference in flow of how balanced differential oil hydraulic cylinder become an important problem.
Patent " 200510020094.X " discloses a kind of controlled by electro-hydraulic proportional pump asymmetrical cylinder closed-loop speed system, by flow shunt relief valve and feed circuit, realizes the difference in flow of differential hydro cylinder.Patent " 200810007666.4 " discloses a kind of pump control type electrohydraulic actuator, is gone the difference in flow of balanced differential oil hydraulic cylinder by the mode of relief valve throttling.Patent " 201310241735.9 " discloses oil hydraulic cylinder control system and the controlling method of the combination drive of a kind of directly driving type servo-pump control electricity liquid, is balanced the difference in flow singly going out hair style oil cylinder by differential unloading valve.All to have employed relief valve balanced flow poor in above three inventions, and in use relief valve is in normally open, and therefore restriction loss comparatively greatly, and system energy efficiency is low and cause system to generate heat, and is not suitable for high-frequency condition of commutation.Patent " 200610012476.2 " discloses a kind of closed electrohydraulic controlling system, adopts the oil hydraulic pump of 3 hydraulic fluid ports to realize being connected with differential hydro cylinder, by the difference in flow of the thrust plate balanced differential oil hydraulic cylinder of oil hydraulic pump.This invention well solves restriction loss problem, but all needs for the differential hydro cylinder of different area difference the thrust plate redesigning oil hydraulic pump, this all more complicated in practical application and structural design; In addition need to be equipped with corresponding hydraulic power separately.Patent " 201310215195.7 " discloses a kind of hydraulic actuator, and oil sources is built-in, and not needing the auxiliary of external equipment, is a kind of integrated product.But the differential hydro cylinder rodless cavity in this invention is connected with fuel tank all the time, hydraulic system can only control flow and the pressure of rod chamber, and hydraulic actuator is ability bidirectional-movement under the effect of external pull only, and therefore service condition has sizable narrow limitation.
Summary of the invention
The object of the invention is to the deficiency overcoming prior art, provide a kind of oil circuit simple, can not leak, compact structure, to grow and the digital pump controlled hydraulic differential cylinder in energy-conservation self-powered source without restriction loss, life-span.
In order to achieve the above object, the technical solution used in the present invention is:
The digital pump controlled hydraulic differential cylinder in self-powered source of the present invention, it comprises hydraulic pressure power unit oil hydraulic cylinder and hydraulic power parts power source, the various piece of power source is all placed in containment vessel, described containment vessel is arranged on oil hydraulic cylinder by fixing device, and described oil hydraulic cylinder comprises a double-action differential hydro cylinder and inserts the built-in sensors of double-action differential hydro cylinder rodless cavity; the structure of described power source is: the oil inlet and outlet of the rod chamber of double-action differential hydro cylinder is by being connected with the first Pilot operated check valve in turn, an oil hydraulic motor in bidirectional shunt oil hydraulic motor, the fluid pipe-line of two-way quantitative oil hydraulic pump and the second Pilot operated check valve is connected with the filler opening that goes out of the rodless cavity of double-action differential hydro cylinder, a hydraulic port of another oil hydraulic motor in bidirectional shunt oil hydraulic motor is communicated with the fluid pipe-line between the oil hydraulic motor of in bidirectional shunt oil hydraulic motor and two-way quantitative oil hydraulic pump and another hydraulic port of another oil hydraulic motor is communicated with fuel tank by connecting line, the described pump shaft of two-way quantitative oil hydraulic pump is connected with the motor shaft of motor, described motor is connected with power system controller, described bidirectional shunt oil hydraulic motor is mechanically connected to together by two oil hydraulic motors by coupling, described first, two Pilot operated check valves form hydraulic lock, the rod chamber of double-action differential hydro cylinder is communicated with fuel tank each via the pipeline that is connected with safety valve with two pumping holes of rodless cavity and two-way quantitative oil hydraulic pump, described sensor is connected with power system controller by guide line, described sensor is to controller output displacement signal or rate signal, the feedback signal of sensor and given signal compare by described power system controller, then control signal is exported to motor to control the operation of motor.
The invention has the beneficial effects as follows: the digital pump controlled hydraulic differential cylinder in self-powered source of the present invention, its self-powered source, not only customer service hydraulic power unit needs external oil sources, oil circuit to lay complicated shortcoming; And integrated embedded control system, eliminate the external equipment of electrical control, as long as also input instruction signal of connecting with the mains can normally use.
Fluid is sealed in the inside of power source by the present invention by fuel tank, reduce the leakage phenomenon of hydraulic system, decreases the impact of outer bound pair hydraulic oil.
The present invention, by the volume shunting action of the bidirectional shunt oil hydraulic motor in hydraulic valve bank, solves the compensatory control problem for the asymmetric flow in double-action differential hydro cylinder two chamber well; Safety valve can not work when system worked well, only just can open when system overload, therefore solve restriction loss problem well, and safety valve structurally all adopts plug-in type, reduces the volume of power source better; System does not adopt solenoid directional control valve, makes system architecture compact, weight saving, decreases the restriction loss of system.
The present invention carrys out the commutation of hydraulic control power plant by driven by motor two-way quantitative oil hydraulic pump, and the form of this pump control cylinder can bear the requirement that commutates for a long time, long service life; The system caused compared to valve-controlled cylinder restriction loss is generated heat excessive phenomenon, and pump control cylinder significantly can save energy, meets the thinking of development of green low-energy consumption.
Accompanying drawing explanation
Fig. 1 is the digital pump controlled hydraulic differential cylinder schematic diagram in self-powered source of the present invention;
Fig. 2 is the digital pump controlled hydraulic differential cylinder structural representation in self-powered source of the present invention.
Embodiment
The digital pump controlled hydraulic differential cylinder in self-powered source of the present invention as shown in drawings, it comprises hydraulic pressure power unit oil hydraulic cylinder and hydraulic power parts power source, the various piece of power source is all placed in containment vessel, described containment vessel is arranged on oil hydraulic cylinder by fixing device, and described oil hydraulic cylinder comprises a double-action differential hydro cylinder 1 and inserts the built-in sensors 9 of double-action differential hydro cylinder 1 rodless cavity; the structure of described power source is: the oil inlet and outlet of the rod chamber of double-action differential hydro cylinder 1 is by being connected with the first Pilot operated check valve in turn, an oil hydraulic motor in bidirectional shunt oil hydraulic motor 5, the fluid pipe-line of two-way quantitative oil hydraulic pump 6 and the second Pilot operated check valve is connected with the filler opening that goes out of the rodless cavity of double-action differential hydro cylinder 1, a hydraulic port of another oil hydraulic motor in bidirectional shunt oil hydraulic motor 5 is communicated with the fluid pipe-line between the oil hydraulic motor of in bidirectional shunt oil hydraulic motor 5 and two-way quantitative oil hydraulic pump 6 and another hydraulic port of another oil hydraulic motor is communicated with fuel tank by connecting line, the described pump shaft of two-way quantitative oil hydraulic pump 6 is connected with the motor shaft of motor, described motor is connected with power system controller, described bidirectional shunt oil hydraulic motor 5 is mechanically connected to together by two oil hydraulic motors by coupling, described first, two Pilot operated check valves form hydraulic lock, the rod chamber of double-action differential hydro cylinder 1 is communicated with fuel tank each via the pipeline that is connected with safety valve with two pumping holes of rodless cavity and two-way quantitative oil hydraulic pump 6, described sensor is connected with power system controller 11 by guide line, described sensor is to controller output displacement signal or rate signal, the feedback signal of sensor and given signal compare by described power system controller, then control signal is exported to motor to control the operation of motor.
Described sensor is displacement transducer or velocity transducer.
The first Pilot operated check valve 3.1, second Pilot operated check valve 3.2 in this device, bidirectional shunt oil hydraulic motor 5, first, second, third and fourth safety valve 4.1,4.2,4.3,4.4 constitute hydraulic valve bank 12.Described bidirectional shunt oil hydraulic motor 5 is mechanically connected to together by two oil hydraulic motors by coupling, and play the effect of volume shunting, described oil hydraulic motor can be the oil hydraulic motor that gear type or plunger type equal-volume are less.First, second, third and fourth described safety valve 4.1,4.2,4.3,4.4 preferably all adopts plug-in type.Described motor 7 is generally actuating motor or stepper motor, motor 7 is provided with power system controller support, and power system controller 11 is arranged on power system controller support.Described power system controller 11 is commercially available, generally uses ARM chip, and the composition of controller is also generally all common version.Control procedure is: whole device is connected into a closed loop control system by controller, described sensor is connected with power system controller by guide line, controller is passed the signal in real time by sensor, the feedback signal of sensor and given signal compare by controller, control the operation of motor again, thus positioning control or speeds control are carried out to oil hydraulic cylinder.
The digital pump controlled hydraulic differential cylinder in self-powered source of the present invention in use, is divided into two kinds of working conditions: piston rod stretches out retracts with piston rod.When supposing that piston rod stretches out, the sense of rotation of motor 7 is forward.In the process of system worked well, first, second, third and fourth safety valve 4.1,4.2,4.3,4.4 does not participate in work, only has when overload and plays a protective role to system.Wherein, first and second safety valve 4.1 and 4.4 respectively to the rod chamber of differential hydro cylinder 1 and rodless cavity work or overload time shield, the pump intake pressure of third and fourth safety valve 4.2 and 4.3 pairs of two-way quantitative oil hydraulic pumps 6 shields.
When control piston bar stretches out, extraneous pulse signal controls motor 7 and rotates forward, two-way quantitative oil hydraulic pump 6 is driven to rotate, now the remote control mouth pressure of the first Pilot operated check valve 3.1 raises, first Pilot operated check valve 3.1 is opened, hydraulic oil flows into the rodless cavity of differential hydro cylinder 1 through pipeline 2, first Pilot operated check valve 3.1 of fluid pipe-line, bidirectional shunt oil hydraulic motor 5, two-way quantitative oil hydraulic pump 6, second Pilot operated check valve 3.2 from the rod chamber of differential hydro cylinder 1, piston rod stretches out.Because the hydraulic oil flowed out from rod chamber is less than the hydraulic oil flowing into rodless cavity, therefore bidirectional shunt oil hydraulic motor 5 can be made up a deficiency and be entered rodless cavity from fuel tank 8, realizes flow-compensated.
When control piston bar is retracted, extraneous pulse signal controls motor 7 and reverses, two-way quantitative oil hydraulic pump 6 is driven to rotate, now the remote control mouth pressure of the second Pilot operated check valve 3.2 raises, second Pilot operated check valve 3.2 is opened, hydraulic oil flows into the rod chamber of differential hydro cylinder 1 through pipeline 10, second Pilot operated check valve 3.2 of fluid pipe-line, two-way quantitative oil hydraulic pump 6, bidirectional shunt oil hydraulic motor 5, first Pilot operated check valve 3.1 from the rodless cavity of differential hydro cylinder 1, piston rod is retracted.Because the hydraulic oil flowed out from rodless cavity is greater than the hydraulic oil flowing into rod chamber, therefore bidirectional shunt oil hydraulic motor 5 can, by unnecessary hydraulic oil row oil-feed tank 8, realize flow-compensated.
When after piston rod movement to certain position, can make motor 7 stall, first, second Pilot operated check valve 3.1 and 3.2 forms hydraulic lock, and therefore the digital pump controlled hydraulic differential cylinder in self-powered source of the present invention can realize good positioning supports function.The digital pump controlled hydraulic differential cylinder in self-powered source of the present invention, in use engineering, sends signal by sensor to power system controller 11 all the time, forms closed loop control.
When outer load is the very large pressure acted on the piston rod; the rodless cavity pressure of differential hydro cylinder is very high; driven by motor oil hydraulic pump rotates forward the pressure that the maximum pump intake pressure obtained still is less than rodless cavity; second Pilot operated check valve 3.2 cannot be opened; now the 3rd safety valve 4.3 will be opened for oil hydraulic pump overflow, thus plays the effect of overload protection to oil hydraulic pump and motor.If outer load exceedes a certain limiting value, the rodless cavity of differential hydro cylinder will have the danger of explosion, and the 4th safety valve 4.4 will be opened for the rodless cavity pressure release of differential hydro cylinder, thus oil hydraulic cylinder is played to the effect of overload protection.
When outer load is the very large pulling force acted on the piston rod; the rod chamber pressure of differential hydro cylinder is very high; the reverse maximum pump intake pressure that obtains of driven by motor oil hydraulic pump is still less than the pressure of rod chamber; first Pilot operated check valve 3.1 cannot be opened; now the second safety valve 4.2 will be opened for oil hydraulic pump overflow, thus plays the effect of overload protection to oil hydraulic pump and motor.If outer load exceedes a certain limiting value, the rod chamber of differential hydro cylinder will have the danger of explosion, and the first safety valve 4.1 will be opened for the rod chamber pressure release of differential hydro cylinder, thus oil hydraulic cylinder is played to the effect of overload protection.
Claims (5)
1. the digital pump controlled hydraulic differential cylinder in self-powered source, it comprises hydraulic pressure power unit oil hydraulic cylinder and hydraulic power parts power source, it is characterized in that: the various piece of power source is all placed in containment vessel, described containment vessel is arranged on oil hydraulic cylinder by fixing device, and described oil hydraulic cylinder comprises a double-action differential hydro cylinder and inserts the built-in sensors of double-action differential hydro cylinder rodless cavity; the structure of described power source is: the oil inlet and outlet of the rod chamber of double-action differential hydro cylinder is by being connected with the first Pilot operated check valve in turn, an oil hydraulic motor in bidirectional shunt oil hydraulic motor, the fluid pipe-line of two-way quantitative oil hydraulic pump and the second Pilot operated check valve is connected with the filler opening that goes out of the rodless cavity of double-action differential hydro cylinder, a hydraulic port of another oil hydraulic motor in bidirectional shunt oil hydraulic motor is communicated with the fluid pipe-line between the oil hydraulic motor of in bidirectional shunt oil hydraulic motor and two-way quantitative oil hydraulic pump and another hydraulic port of another oil hydraulic motor is communicated with fuel tank by connecting line, the described pump shaft of two-way quantitative oil hydraulic pump is connected with the motor shaft of motor, described motor is connected with power system controller, described bidirectional shunt oil hydraulic motor is mechanically connected to together by two oil hydraulic motors by coupling, described first, two Pilot operated check valves form hydraulic lock, the rod chamber of double-action differential hydro cylinder is communicated with fuel tank each via the pipeline that is connected with safety valve with two pumping holes of rodless cavity and two-way quantitative oil hydraulic pump, described sensor is connected with power system controller by guide line, described sensor is to controller output displacement signal or rate signal, the feedback signal of sensor and given signal compare by described power system controller, then control signal is exported to motor to control the operation of motor.
2. the digital pump controlled hydraulic differential cylinder in self-powered source according to claim 1, is characterized in that: the safety valve on the pipeline be connected with the rod chamber of double-action differential hydro cylinder and two pumping holes of rodless cavity and two-way quantitative oil hydraulic pump all adopts plug-in type.
3. the digital pump controlled hydraulic differential cylinder in self-powered source according to claim 1 and 2, is characterized in that: described sensor is displacement transducer or velocity transducer.
4. the digital pump controlled hydraulic differential cylinder in self-powered source according to claim 3, is characterized in that: described oil hydraulic motor is gear-type hydraulic motor or plunger hydraulic motor.
5. the digital pump controlled hydraulic differential cylinder in self-powered source according to claim 4, is characterized in that: described motor is actuating motor or stepper motor.
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| CN201410293460.8A CN104047912B (en) | 2014-06-25 | 2014-06-25 | The digital pump controlled hydraulic differential cylinder in self-powered source |
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| CN104047912B true CN104047912B (en) | 2016-02-24 |
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| EP3566795A1 (en) * | 2018-05-07 | 2019-11-13 | Primetals Technologies Germany GmbH | Lifting device for a metallurgical ladle and treatment device for liquid metal |
| CN108916139B (en) * | 2018-06-15 | 2020-08-07 | 沪东中华造船(集团)有限公司 | Hydraulic type jig frame supporting system and using method thereof |
| CN110259770B (en) * | 2019-06-03 | 2020-10-30 | 长沙中联重科环境产业有限公司 | Compression garbage truck press-filling system and noise control method |
| CN114508520A (en) * | 2020-11-16 | 2022-05-17 | 中国石油化工股份有限公司 | Director hydraulic integrated system for coiled tubing |
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Patent Citations (6)
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| JPH04290604A (en) * | 1991-03-18 | 1992-10-15 | Hitachi Ltd | Fluid pressure servo system |
| CN1800654A (en) * | 2005-12-20 | 2006-07-12 | 武汉科技大学 | Asymmetric cylinder closed-loop speed system controlled by electro-hydraulic proportional pump |
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