CN111828409A - Hydraulic drive unit based on two-stage energy supply and load port independent valve control technology - Google Patents

Hydraulic drive unit based on two-stage energy supply and load port independent valve control technology Download PDF

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Publication number
CN111828409A
CN111828409A CN202010719032.2A CN202010719032A CN111828409A CN 111828409 A CN111828409 A CN 111828409A CN 202010719032 A CN202010719032 A CN 202010719032A CN 111828409 A CN111828409 A CN 111828409A
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Prior art keywords
valve
load port
drive unit
load
port independent
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CN202010719032.2A
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Inventor
晁智强
薛大兵
韩寿松
宁初明
刘相波
靳莹
李华莹
谭永营
李勋
王飞
郭浩
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Zhejiang Rail Transit Operation Management Group Co ltd
Academy of Armored Forces of PLA
Institute of Quartermaster Engineering Technology Institute of Systems Engineering Academy of Military Sciences
Original Assignee
Zhejiang Rail Transit Operation Management Group Co ltd
Academy of Armored Forces of PLA
Institute of Quartermaster Engineering Technology Institute of Systems Engineering Academy of Military Sciences
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Priority to CN202010719032.2A priority Critical patent/CN111828409A/en
Publication of CN111828409A publication Critical patent/CN111828409A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F15B1/024—Installations or systems with accumulators used as a supplementary power source, e.g. to store energy in idle periods to balance pump load
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F15B1/027—Installations or systems with accumulators having accumulator charging devices
    • F15B1/0275—Installations or systems with accumulators having accumulator charging devices with two or more pilot valves, e.g. for independent setting of the cut-in and cut-out pressures
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/625—Accumulators

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

The invention relates to the technical field of robots, and discloses a hydraulic drive unit based on two-stage energy supply and load port independent valve control technology, which comprises a load port independent valve, a two-position two-way servo valve, a switch valve, a hydraulic cylinder and a control unit, wherein the load port independent valve comprises a load and a pressure switching valve, the load port independent valve realizes the control of an actuator by using four two-position two-way valves through the arrangement of the load port independent valve, the load port independent valve is different from a three-position four-way valve, the load port independent valve control can realize the independent throttling control of the inlet and outlet of the actuator, the energy supply of two pressures is realized by connecting two groups of two-position two-way servo valves and the switch valve with the output ends at two sides of the pressure switching valve, then the pressure switching is realized by the pressure switching valve, under the condition of meeting the requirement of the hydraulic drive unit, low-pressure, the energy consumption of the hydraulic driving unit is reduced, and the efficiency is improved.

Description

Hydraulic drive unit based on two-stage energy supply and load port independent valve control technology
Technical Field
The invention relates to the technical field of robots, in particular to a hydraulic drive unit based on two-stage energy supply and load port independent valve control technology.
Background
In the moving process of the quadruped robot, the load change amplitude of the leg hydraulic driving unit is large, and the proportion of the large load existing time in the whole moving period is small, namely the hydraulic driving unit in the system is stressed in an intermediate state with not too large load most of the time, so that most of the hydraulic driving units are in an excess pressure state, and the throttling loss at the valve opening of the servo valve is inevitably caused. Therefore, the smaller the load of the hydraulic drive unit, the greater the throttling loss thereof. In summary, to reduce the energy consumption of the hydraulic system of the quadruped robot, efforts must be made to increase the degree of matching of the system pressure supply with the hydraulic drive unit requirements. Therefore, a hydraulic drive unit based on two-stage power supply and load port independent valve control technology is needed to solve the above problems.
Disclosure of Invention
Technical problem to be solved
In view of the defects of the prior art, the invention provides a hydraulic drive unit based on two-stage energy supply and load port independent valve control technology to solve the problems.
(II) technical scheme
In order to achieve the purpose, the invention provides the following technical scheme: hydraulic drive unit based on two-stage energy supply and load mouth independent valve accuse technique, including load mouth independent valve, two lead to servo valve, the ooff valve, pneumatic cylinder and the control unit, load mouth independent valve includes load and pressure switching valve, the load is connected with the connecting rod structure of pressure switching valve, the quantity of two lead to servo valve and ooff valve is two, the both sides output of pressure switching valve is connected with the input of two lead to servo valve and ooff valve respectively, the output interconnect of two ooff valves, the output of two lead to servo valves all is connected with pneumatic cylinder and the control unit's input.
(III) advantageous effects
Compared with the prior art, the invention provides a hydraulic drive unit based on two-stage energy supply and load port independent valve control technology, which has the following beneficial effects:
1. this hydraulic drive unit based on two-stage energy supply and load mouth independent valve accuse technique, setting through the load mouth independent valve, load mouth independent valve utilizes four two-position two-way valves to realize the control to the executor, different with the three-position cross valve, load mouth independent valve accuse can realize advancing the executor, the independent throttle control of export is controlled, through utilizing two sets of two-position two-way servo valve and ooff valve to be connected with the both sides output of pressure switching valve, realize the energy supply of two kinds of pressures, then realize pressure switching through the pressure switching valve, under the demand condition who satisfies hydraulic drive unit, preferentially use low pressure fluid to supply energy, can reduce loss of pressure to a certain extent, reduce hydraulic drive unit's energy consumption, high efficiency.
2. According to the hydraulic driving unit based on the two-stage energy supply and load port independent valve control technology, the problem of coupling of the throttling effects of the inlet and the outlet of the three-position four-way valve in the single-pump multi-actuator hydraulic system is solved through the application of the load port independent valve control technology in the hydraulic driving unit, meanwhile, the load port independent valve control technology can achieve large system back pressure, and the stability of the system is improved.
Drawings
FIG. 1 is a schematic diagram of the control principle of the present invention;
fig. 2 is a schematic view of the control principle of the load port independent valve of the present invention.
In the figure: 1 load port independent valve, 11 loads, 12 pressure switching valves, 2 two-position two-way servo valves, 3 switch valves, 4 hydraulic cylinders and 5 control units.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-2, the present invention provides a hydraulic driving unit based on two-stage energy supply and load port independent valve 1 control technology, including a load port independent valve 1, two-position two-way servo valves 2, a switch valve 3, a hydraulic cylinder 4 and a control unit 5, where the load port independent valve 1 includes a load 11 and a pressure switching valve 12, the load 11 is connected with a link structure of the pressure switching valve 12, the number of the two-position two-way servo valves 2 and the number of the switch valve 3 are two, output ends of the pressure switching valve 12 are respectively connected with input ends of the two-position two-way servo valve 2 and the switch valve 3, output ends of the two switch valves 3 are connected with each other, output ends of the two-position two-way servo valves 2 are both connected with input ends of the hydraulic cylinder 4 and the control unit 5, the load port independent valve 1 uses four two-position two-way valves to control an actuator, unlike a three-position, the control of the load port independent valve 1 can realize independent throttling control of an inlet and an outlet of an actuator, two groups of two-position two-way servo valves 2 and a switch valve 3 are utilized to be connected with output ends at two sides of a pressure switching valve 12, energy supply of two kinds of pressure is realized, then pressure switching is realized through the pressure switching valve 12, energy supply is performed by preferentially using low-pressure oil under the condition of meeting the requirement of a hydraulic driving unit, pressure loss can be reduced to a certain degree, the energy consumption of the hydraulic driving unit is reduced, the efficiency is improved, the application of the control technology of the load port independent valve 1 in the hydraulic driving unit solves the problem of coupling of the inlet throttling effect and the outlet throttling effect of a three-position four-way valve in a single-pump multi-actuator hydraulic system, meanwhile, the control technology of the load port independent valve 1 can realize larger system back pressure, and the.
And similarly, assuming that the energy supply flow and the pressure of the hydraulic oil source are always stable, the actuator in the hydraulic drive unit is in a static balance state. The relationship between the flow rate of the rod-free chamber and the area of the two chambers of the hydraulic cylinder 4 can be expressed as follows:
Figure BDA0002599292110000031
wherein Q isa、QbFlow into the rodless and rod chambers, respectively, of the hydraulic cylinder 4, Aa、AbThe areas of the rodless chamber and the rod chamber of the hydraulic cylinder 4, respectively.
The relationship between the flow rate of the rodless and rod chambers of the hydraulic cylinder 4 and the opening of the load port 11 can be expressed as:
Figure BDA0002599292110000032
Figure BDA0002599292110000033
wherein, CdIs the flow coefficient, w is the orifice circumference, xa、xbThe valve core displacement amount, Δ p, of the inlet and outlet throttle valves, respectivelya、ΔpbDifferential pressure before and after the inlet and outlet throttle valves, delta pa＝ps-pa，Δpb＝pb-0＝pb。
Order:
Figure BDA0002599292110000041
Figure BDA0002599292110000042
comprehensive type
Figure BDA0002599292110000043
Figure BDA0002599292110000044
Figure BDA0002599292110000045
And
Figure BDA0002599292110000046
obtaining:
Figure BDA0002599292110000047
namely:
μ2(ps-pa)＝R2pb
the hydraulic cylinder 4 is always in a static equilibrium state, namely:
F＝paAa-pbAb
will be the formula mu2(ps-pa)＝R2pbSubstituted formula F ═ paAa-pbAbObtaining:
Figure BDA0002599292110000048
the relationship between the movement speed and the flow of the hydraulic cylinder 4 is as follows:
Figure BDA0002599292110000049
is composed of
Figure BDA00025992921100000410
And
Figure BDA00025992921100000411
obtaining:
Figure BDA00025992921100000412
the energy conversion efficiency η' of the hydraulic drive unit is then:
Figure BDA00025992921100000413
formula (II)
Figure BDA00025992921100000414
The areas of the two cavities of the middle hydraulic cylinder 4 cannot be changed, so the efficiency eta 'of the hydraulic driving unit is only related to the opening degree of a valve core displacement throttling port of the inlet and outlet throttling valves, the ratio mu of the opening degrees of the inlet and the outlet of the three-position four-way valve cannot be changed, the throttling port is restricted by the load 11F and cannot be randomly adjusted, and the efficiency eta' of the hydraulic driving unit can hardly be manually controlled; the ratio mu of the inlet throttle valve port to the outlet throttle valve port can be changed at any time under the 1-control technology of the load port independent valve
Figure BDA0002599292110000051
It is known that the efficiency η' of the hydraulic drive unit is higher as the throttle inlet is larger and smaller, that is, the throttle inlet is larger and the throttle outlet is smaller, so that the efficiency of the hydraulic drive unit can be improved by employing the throttle outlet as much as possible while ensuring that the throttle inlet is in a large opening state during the operation of the hydraulic drive unit.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (4)

1. Hydraulic drive unit based on two-stage energy supply and load mouth independent valve accuse technique, including load mouth independent valve (1), two-way servo valve (2), ooff valve (3), pneumatic cylinder (4) and the control unit (5), its characterized in that: the load port independent valve (1) comprises a load (11) and a pressure switching valve (12), and the load (11) is connected with a connecting rod structure of the pressure switching valve (12).
2. The hydraulic drive unit based on two-stage energy supply and load port independent valve control technology of claim 1, wherein: the number of the two-position two-way servo valves (2) and the number of the switch valves (3) are two, and the output ends of the two sides of the pressure switching valve (12) are respectively connected with the input ends of one two-position two-way servo valve (2) and one input end of one switch valve (3).
3. The hydraulic drive unit based on two-stage power supply and load port independent valve control technology of claim 2, wherein: the output ends of the two switch valves (3) are connected with each other.
4. The hydraulic drive unit based on two-stage power supply and load port independent valve control technology of claim 3, wherein: and the output ends of the two-position two-way servo valves (2) are connected with the input ends of the hydraulic cylinder (4) and the control unit (5).
CN202010719032.2A 2020-07-23 2020-07-23 Hydraulic drive unit based on two-stage energy supply and load port independent valve control technology Pending CN111828409A (en)

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Publication number Priority date Publication date Assignee Title
US20060218912A1 (en) * 2005-03-30 2006-10-05 Shin Caterpillar Mitsubishi Ltd. Hydraulic system having variable back pressure control
CN103122648A (en) * 2012-12-28 2013-05-29 上海三一重机有限公司 Multi-way valve hydraulic control system, rectilinear walking control valve and excavator
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
CN105570203A (en) * 2016-01-12 2016-05-11 浙江大学 Efficient and high-precision hydraulic control system adopting combination of pump and valve
CN106402059A (en) * 2016-12-26 2017-02-15 徐工集团工程机械有限公司 Load port individual valve, hydraulic bus control system and engineering machinery
CN108167257A (en) * 2017-12-30 2018-06-15 浙江大学 The TBM support shoe hydraulic systems of Parallel Control
CN108343649A (en) * 2018-04-14 2018-07-31 华东交通大学 Load port based on single side outlet throttling control valve group/discharge capacity autonomous control system
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Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060218912A1 (en) * 2005-03-30 2006-10-05 Shin Caterpillar Mitsubishi Ltd. Hydraulic system having variable back pressure control
CN103122648A (en) * 2012-12-28 2013-05-29 上海三一重机有限公司 Multi-way valve hydraulic control system, rectilinear walking control valve and excavator
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
CN105570203A (en) * 2016-01-12 2016-05-11 浙江大学 Efficient and high-precision hydraulic control system adopting combination of pump and valve
CN106402059A (en) * 2016-12-26 2017-02-15 徐工集团工程机械有限公司 Load port individual valve, hydraulic bus control system and engineering machinery
CN108167257A (en) * 2017-12-30 2018-06-15 浙江大学 The TBM support shoe hydraulic systems of Parallel Control
CN108343649A (en) * 2018-04-14 2018-07-31 华东交通大学 Load port based on single side outlet throttling control valve group/discharge capacity autonomous control system
CN208185095U (en) * 2018-04-14 2018-12-04 华东交通大学 Load port based on single side outlet throttling control valve group/discharge capacity autonomous control system

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