CN109654079A - The outlet throttling load port separate control valves that full switch valve group is closed - Google Patents

The outlet throttling load port separate control valves that full switch valve group is closed Download PDF

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Publication number
CN109654079A
CN109654079A CN201710949115.9A CN201710949115A CN109654079A CN 109654079 A CN109654079 A CN 109654079A CN 201710949115 A CN201710949115 A CN 201710949115A CN 109654079 A CN109654079 A CN 109654079A
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China
Prior art keywords
valve
control
controlling unit
low pressure
pressure oil
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CN201710949115.9A
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CN109654079B (en
Inventor
丁孺琦
王胜
胡国良
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East China Jiaotong University
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East China Jiaotong University
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/023Excess flow valves, e.g. for locking cylinders in case of hose burst
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08Servomotor systems incorporating electrically operated control means
    • F15B21/087Control strategy, e.g. with block diagram

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

A kind of outlet throttling load port separate control valves for engineering machinery, so that inlet and outlet can independently be connected to high pressure or low pressure oil way, realize energy regeneration and recycling using two-bit triplet reversal valve as two chamber high-low pressure oil passage change-over valve of hydraulic cylinder;Guarantee that flow controlling unit is always positioned at hydraulic cylinder and exports on oil circuit by three position four-way directional control valve reversal valve, actuator speed is controlled in a manner of import standard-sized sheet, outlet throttle timing, inlet throttle is eliminated and loses and reduce flow control valve quantity;Flow controlling unit is in parallel using multiple two-way switch valves, by pulse code modulation or the digital control method of Pulse number modulation, realizes flow control function.All elements of the valve are switching mode, without using any ratio control unit.The present invention can be effectively reduced the development cost of load port separate control valves, further decrease valve port restriction loss.It can realize that inlet and outlet independent control, energy regeneration and recycling etc. reduce the function of system energy consumption simultaneously.

Description

The outlet throttling load port separate control valves that full switch valve group is closed
Technical field
The present invention relates to hydraulic control valve, especially a kind of engineering machinery hydraulic control valve.
Background technique
Construction machinery hydraulic system controls multiple actuators by limited quantity power source, and there is flow to become in real time with pressure requirements The features such as change, impedance load and Exceed load frequent changes.Control valve is the core control element of construction machinery hydraulic system.It passes Construction machinery hydraulic system control valve unite as the multi-way valve of single spool valves, passes in and out valve port mechanical linkage, therefore hardware versatility It is poor, it is handling to be difficult to be optimal with energy-saving.Load port separate control valves break the constraint of inlet and outlet mechanical couplings, can be only Site control import and export orifice size, be effectively improved traditional multi-way valve there are the problem of.But existing load port separate control valves It is all made of the combination of 2 3-position 4-way proportional direction valves or 4 bi-bit bi-pass proportioning valves, disengaging restriction is both needed to Proportional Valve-controlled System, therefore there are the losses of unnecessary inlet throttle, and since ratio control unit is more, cause development cost higher, safety Property and reliability are lower, tend not to meet the requirement of the low cost, high reliability in industrial products.
Summary of the invention
In order to overcome the shortcomings of the high cost of existing load port separate control valves, low reliability, the present invention provides one kind can Effectively meet inlet and outlet independent control function, while restriction loss is few, and element cost used is low, controls simple and safe and reliable Construction machinery hydraulic system control valve.
The technical solution adopted by the present invention to solve the technical problems is:
A kind of outlet throttling load port separate control valves that full switch valve group is closed, including rodless cavity high-low pressure oil circuit electromagnetic switching valve 1, rod chamber high-low pressure oil passage change-over valve 2, solenoid directional control valve 3, flow controlling unit 4;P mouthfuls of companies of the load port separate control valves Pump high pressure oil port, T mouthfuls of connection fuel tanks are connect, actuator port A and B are reversal valve actuator port a3 and b3, are passed in and out respectively with hydraulic cylinder Mouth connection;The reversal valve 3 controls the direction of motion and stopping of hydraulic cylinder using 3-position 4-way direction valve;Reversal valve 3 into Hydraulic fluid port p3 is connected to the actuator port a1 of rodless cavity high-low pressure oil passage change-over valve 1;The oil return opening t3 of reversal valve 3 and and rod chamber height The actuator port a2 of low pressure oil way switching valve 2 is connected to;Using two-bit triplet solenoid valve as high-low pressure oil passage change-over valve 1 and 2, make High pressure or low pressure oil way can be independently connected to by obtaining two chamber of hydraulic cylinder, realize the energy regeneration and recycling of hydraulic cylinder;
Flow controlling unit 4 is arranged between rod chamber high-low pressure oil passage change-over valve 1,2 and reversal valve 3, oil inlet a4 with change It is connected to the oil return opening t3 of valve 3, oil outlet b4 is connected with the actuator port a2 of switching valve 2;Guarantee the flow by reversal valve 3 On hydraulic cylinder outlet oil circuit, the speed of actuator is controlled with import standard-sized sheet, outlet throttling control method always for control unit 4 Degree reduces the quantity and inlet throttle loss of flow control valve.
Further, flow controlling unit is made of multiple unidirectional through-flow switch valves, switch valve group according to latus rectum by it is small to It is arranged in parallel greatly, to replace proportional control valve;Control mode uses pulse code modulation (pcm) or Pulse number modulation (PNM) Digital control method change the combination of switch valve on off operating mode by controlling the action sequence of each valve port unlatching/closing, after And adjust the output flow of flow controlling unit.
Further, the switch valve in the flow controlling unit is mounted in an independent valve block by inserting mode, And it is commonly mounted in a valve block with other reversal valves and switching valve by board-like mounting means.
Beneficial effects of the present invention are mainly manifested in:
1. can effectively meet the motion control requirement under four-quadrant load behavior by reversal valve work bit map;Meanwhile It realizes the functions such as flow regeneration, energy regenerating, reduces the energy loss of hydraulic system;
2. outlet throttling control mode makes import standard-sized sheet, the valve port pressure loss of inlet valve is reduced;Further, since only needing list Side throttling control, reduces the quantity of proportional flow control unit;
3. replacing conventional proportional valve using multiple switch valve parallel combination, save the cost simultaneously improves reliability.Simultaneously as each The latus rectum of switch valve is much smaller than the latus rectum of single proportioning valve, therefore can optimal control performance, raising response speed and robustness.
Detailed description of the invention
Fig. 1 is the outlet throttling load port separate control valves schematic diagram that full switch valve group according to the present invention is closed.
Fig. 2 is the schematic diagram of flow controlling unit.
Fig. 3 is the multi executors hydraulic control system schematic diagram for embodiment.
Fig. 4 is the pulse-code-odulation and output stream spirogram for the flow controlling unit of 5 switch valve parallel connections.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.
Referring to Fig.1, Fig. 2 and Fig. 3, a kind of outlet throttling load port separate control valves that full switch valve group is closed, the control valve Hydraulic actuator can be driven in four-quadrant loaded work piece.In impedance load, hydraulic cylinder is extended and retracts;In Exceed load When, two chamber of hydraulic cylinder can be connected to the differential mode of low pressure oil return line simultaneously, work and utilize Exceed load in energy recuperation mode Energy is without oil pump feed;In multi executors system, pump high-pressure oil passage can be connected to simultaneously by being lightly loaded two chamber of hydraulic cylinder, be worked in flow Regeneration mode reduces the fuel supply flow rate of pump.The speed of hydraulic cylinder can be adjusted by flow controlling unit, using pulse code tune The digital control method of (PCM) or pulse number modulation (PNM) is made, the unlatching of each switch valve in flow controlling unit is changed And closed state, the action sequence of regulating switch valve then adjust the total flow by flow controlling unit.
In the present embodiment, 1 power loss of switching valve, switching valve 2 it is electric, 3 electromagnet a of reversal valve obtains electric, and hydraulic cylinder is without bar Chamber connection pump high pressure oil, rod chamber are connected to low pressure oil return line, and flow control valve is between actuator port B and switching valve 2, piston Bar stretches out, and pushes resistant load, and movement velocity is adjusted by flow controlling unit 4;
In the present embodiment, the switching valve 1 obtains electric, 2 power loss of switching valve, and 3 electromagnet b of reversal valve obtains electric, hydraulic cylinder rodless cavity company Logical low pressure oil return line, rod chamber connection pump high pressure oil, flow control valve is between actuator port A and switching valve 2, piston contracting It returns, pushes resistant load, movement velocity is adjusted by flow controlling unit 4;
In the present embodiment, the equal power loss of switching valve 1 and 2,3 electromagnet a of reversal valve obtains electric, and hydraulic cylinder rodless cavity and rod chamber are equal Connection pump high pressure oil, piston stretch out, and form energy regeneration circuit, the oil return of rod chamber flows back to rodless cavity again, reduces the institute of pump Need flow;
In the present embodiment, the switching valve 1 and 2 it is electric, 3 electromagnet a of reversal valve obtains electric, and hydraulic cylinder rodless cavity and rod chamber are equal It is connected to low pressure oil return line, piston stretches out back, forms energy recovery circuit, and rod chamber is flowed back in the oil return of rodless cavity again, and recycling is super The energy more loaded is not necessarily to oil pump feed;
In the present embodiment, the switching valve 1 and 2 it is electric, 3 electromagnet b of reversal valve obtains electric, and hydraulic cylinder rodless cavity and rod chamber are equal It is connected to low pressure oil return line, piston retracts, and forms energy recovery circuit, and rod chamber is flowed back in the oil return of rodless cavity again, and recycling surmounts The energy of load is not necessarily to oil pump feed;
In the present embodiment, the switching valve 1, switching valve 2, reversal valve 3 and the equal power loss of flow controlling unit, during reversal valve 3 is in Position off state, each switch valve is closed in flow controlling unit, by the cutoff function of switch valve, so that hydraulic cylinder stops at Required position.
Referring to Fig. 4, the control method of flow controlling unit is as follows: in the present embodiment, for the stream of 5 switch valves composition Control unit is measured, flow of each switch valve in rated differential head isq i(i=1,2,3,4,5).Switch valve is received from number control 0 signal of device processed is then closed, and 1 signal received from digitial controller is then opened.The on off operating mode of switch valve is binary code 1, can realize in total 2 using 5 binary codes5The adjusting of kind control flow.Each binary code corresponds to one group of switch Combinations of states, the control flow under the state are then the sum of the flow by open state switch valve.Controller is according to target control Valve port opening needed for flow rate calculation processed exports corresponding binary code after quantization, can pass through outlet throttling control mode Realize the speed control of hydraulic cylinder.
It should be noted that the resolution ratio of flow control is determined by the switch valve quantity in flow controlling unit;If needed The resolution ratio of flow is improved, the difference of through-current capability when can expand the quantity of paralleling switch valve, and reduce each valve standard-sized sheet.

Claims (5)

1. the outlet throttling load port separate control valves that a kind of full switch valve group is closed, it is characterised in that: including rodless cavity high-low pressure Oil passage change-over valve, rod chamber high-low pressure oil passage change-over valve, reversal valve, flow controlling unit, the reversal valve actuator port and liquid Cylinder pressure inlet and outlet connection, the direction of motion and stopping of hydraulic cylinder are controlled using 3-position 4-way direction valve;The oil inlet of reversal valve It is connected to respectively with the high-low pressure oil passage change-over valve actuator port of rodless cavity and rod chamber with oil return opening, using two-bit triplet reversal valve As high-low pressure oil passage change-over valve, two chamber of hydraulic cylinder is allowed independently to be connected to high pressure or low pressure oil way, realizes hydraulic cylinder Energy regeneration and recycling.
2. outlet throttling load port separate control valves as described in claim 1, it is characterised in that: flow controlling unit is arranged in Between rod chamber high-low pressure oil passage change-over valve and reversal valve, guarantee that the flow controlling unit is in hydraulic cylinder always by reversal valve Export oil circuit on, with import standard-sized sheet, outlet throttling control method control actuator speed, reduce flow control valve quantity and Inlet throttle loss.
3. the outlet throttling load port separate control valves as described in claim 1 and 2, it is characterised in that: further, flow control Unit is made of multiple unidirectional through-flow switch valves, and switch valve group is arranged in parallel according to latus rectum is ascending, to replace ratio control Valve processed;Control mode controls each valve using pulse code modulation (pcm) or the digital control method of Pulse number modulation (PNM) Mouth unlatching/closing action sequence, changes the combination of switch valve on off operating mode, then adjusts the output stream of flow controlling unit Amount.
4. outlet throttling load port separate control valves as claimed in claim 1 or 2, it is characterised in that: the switching valve and change It is switching regulator solenoid valve to valve, the constituent element of the flow controlling unit is bi-bit bi-pass electromagnetic switch valve.
5. outlet throttling load port separate control valves as claimed in claim 1 or 2, it is characterised in that: in flow controlling unit Switch valve be mounted in an independent valve block by inserting mode, and pass through board-like installation side with other reversal valves and switching valve Formula is commonly mounted in a valve block.
CN201710949115.9A 2017-10-12 2017-10-12 Full-switch valve combined outlet throttle load port independent control valve Active CN109654079B (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110529450A (en) * 2019-08-14 2019-12-03 杭州国辰正域科技有限公司 Big flow low power consumption high-precision hydraulic speed regulation system based on differential principle before valve
CN111594069A (en) * 2020-05-19 2020-08-28 江苏理工学院 Turnover type elevator control method based on load port independent control
CN111997964A (en) * 2020-07-16 2020-11-27 浙江工业大学 High-frequency-response high-precision direction displacement hydraulic system and load control method thereof
CN112123725A (en) * 2020-07-16 2020-12-25 浙江工业大学 Injection molding machine die-casting electro-hydraulic system and control method thereof
CN113009937A (en) * 2021-04-19 2021-06-22 福州大学 Flow control system and control method for array type switch valve

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CN104929992A (en) * 2015-04-17 2015-09-23 燕山大学 Energy-saving design method for variable-load servo control system
CN105065361A (en) * 2015-09-09 2015-11-18 太原理工大学 Proportional flow unit under compound control of electromagnetic switch valves and proportional throttle valve in parallel
CN105422523A (en) * 2016-01-05 2016-03-23 浙江大学 Digital hydraulic flow regulation system
CN105757017A (en) * 2016-03-24 2016-07-13 中国北方车辆研究所 Load-sensitive proportional throttle valve for double-acting cylinders
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JPH11351202A (en) * 1998-06-10 1999-12-24 Shin Caterpillar Mitsubishi Ltd Load sensing hydraulic circuit
JP2002286002A (en) * 2001-03-26 2002-10-03 Kayaba Ind Co Ltd Hydraulic controlling device
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CN101864965A (en) * 2010-05-17 2010-10-20 浙江大学 Pressure flow rate composite synchronization control energy-saving type shield propelling system
CN102182730A (en) * 2011-05-05 2011-09-14 四川省成都普什机电技术研究有限公司 Movable arm flow re-generation system with potential energy recovery device for excavator
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110529450A (en) * 2019-08-14 2019-12-03 杭州国辰正域科技有限公司 Big flow low power consumption high-precision hydraulic speed regulation system based on differential principle before valve
CN111594069A (en) * 2020-05-19 2020-08-28 江苏理工学院 Turnover type elevator control method based on load port independent control
CN111594069B (en) * 2020-05-19 2021-08-24 江苏理工学院 Turnover type elevator control method based on load port independent control
CN111997964A (en) * 2020-07-16 2020-11-27 浙江工业大学 High-frequency-response high-precision direction displacement hydraulic system and load control method thereof
CN112123725A (en) * 2020-07-16 2020-12-25 浙江工业大学 Injection molding machine die-casting electro-hydraulic system and control method thereof
CN113009937A (en) * 2021-04-19 2021-06-22 福州大学 Flow control system and control method for array type switch valve

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