CN108331793B - Hydraulic pressure reposition of redundant personnel system of circuit control pressure proportion - Google Patents
Hydraulic pressure reposition of redundant personnel system of circuit control pressure proportion Download PDFInfo
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- CN108331793B CN108331793B CN201810123922.XA CN201810123922A CN108331793B CN 108331793 B CN108331793 B CN 108331793B CN 201810123922 A CN201810123922 A CN 201810123922A CN 108331793 B CN108331793 B CN 108331793B
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- Prior art keywords
- proportional
- pressure
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- valve
- hydraulic
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
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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
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/041—Removal or measurement of solid or liquid contamination, e.g. filtering
-
- 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
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
- F15B21/087—Control strategy, e.g. with block diagram
-
- 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
- F15B2211/205—Systems with pumps
- F15B2211/20507—Type of prime mover
- F15B2211/20515—Electric motor
-
- 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
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20538—Type of pump constant capacity
Abstract
The invention discloses a hydraulic pressure shunting system with a circuit for controlling pressure proportion, which comprises an oil tank, a shunting valve, a constant delivery pump, a motor and a proportion control circuit unit, wherein one output end of the shunting valve is respectively connected with a first electro-hydraulic proportion pressure valve and a first stop valve, the other output end of the shunting valve is respectively connected with a second electro-hydraulic proportion pressure valve and a second stop valve, the first electro-hydraulic proportion pressure valve is connected with a first proportion amplifier, and the proportion control circuit unit is connected with the first proportion amplifier and the second proportion amplifier. The invention takes two output branches of the proportional control circuit unit as executing elements, controls the voltage ratio of the two output branches by controlling the displacement of the electric brush of the potentiometer, and further controls the displacement ratio of the valve cores of the first electro-hydraulic proportional pressure valve and the second electro-hydraulic proportional pressure valve, thereby realizing the purpose of randomly distributing the pressure ratio of the two partial pressure branches, pushing the load to move, finally realizing the proportional distribution of any pressure, and having wide application range.
Description
Technical Field
The invention relates to a hydraulic shunt system, in particular to a hydraulic shunt system with a circuit for controlling pressure proportion.
Background
The electro-hydraulic proportional valve is an element in which a proportional electromagnet in the valve generates corresponding action according to an input electric signal, so that a valve core of a working valve generates displacement, the size of a valve port is changed, and pressure and flow output in proportion to input voltage is completed. Compared with a common hydraulic valve with manual regulation and on-off control, the electro-hydraulic proportional valve can obviously simplify a hydraulic system, realize control on complex programs and motion rules, facilitate mechanical and electrical integration, greatly improve the control level of the hydraulic system through electric signal control, have strong pollution resistance, greatly reduce working faults caused by pollution and improve the working stability and reliability of the hydraulic system. Therefore, the application field is increasingly widened, and the good application prospect is shown.
At present, a corresponding hydraulic system is specially designed for realizing a certain specific pressure ratio parameter, that is, one hydraulic system can only realize one specific pressure ratio and cannot realize other pressure ratios, if other pressure ratios are realized, other hydraulic systems need to be additionally designed for meeting the requirement, the application range is narrow, the cost is high, and therefore a hydraulic system capable of realizing pressure regulation in any ratio is urgently needed.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide a hydraulic shunt system with a circuit for controlling the pressure proportion, which can realize proportion distribution of any pressure and has a wide application range.
In order to achieve the above object, the present invention adopts the following technical solutions: a hydraulic pressure shunting system for controlling pressure proportion by a circuit comprises an oil tank, a shunting valve, a constant delivery pump, a motor and a proportion control circuit unit, wherein the oil tank, the input end of the shunting valve and the motor are all connected with the constant delivery pump, a coupler is connected between the motor and the constant delivery pump, one output end of the shunting valve is respectively connected with a first electro-hydraulic proportion pressure valve and a first stop valve, the other output end of the shunting valve is respectively connected with a second electro-hydraulic proportion pressure valve and a second stop valve, the input end of the first electro-hydraulic proportion pressure valve is connected with the output end of a first proportion amplifier, the input end of the first electro-hydraulic proportion pressure valve is also connected with the reverse input end of a first proportion amplifier through a first inductive displacement sensor, the input end of the second electro-hydraulic proportion pressure valve is connected with the output end of a second proportion amplifier, and the input end of the second electro-hydraulic proportion pressure valve is also connected with the reverse input, and two voltage output branches of the proportional control circuit unit are respectively connected with the homodromous input end of the first proportional amplifier and the homodromous input end of the second proportional amplifier.
Further, the proportional control circuit unit comprises a potentiometer, a movable end of the potentiometer is connected with a reverse input end of the subtraction operator module and a same-direction input end of the first following voltage operator module, one fixed end of the potentiometer is connected with a power supply and a same-direction input end of the subtraction operator module, an output end of the subtraction operator module is connected with a same-direction input end of the second following voltage operator module, and two voltage output branches of the proportional control circuit unit are respectively an output end of the first following voltage operator module and an output end of the second following voltage operator module.
Further, the oil supply amount of the fixed displacement pump is a constant value.
Further, an oil suction filter is connected between an oil inlet of the constant delivery pump and the oil tank.
Further, an air filter and a liquid level meter are arranged on the oil tank.
Compared with the prior art, the invention has the beneficial effects that: the invention takes two output branches of the proportional control circuit unit as executing elements, controls the voltage ratio of the two output branches by controlling the displacement of the electric brush of the potentiometer, and further controls the displacement ratio of the valve cores of the first electro-hydraulic proportional pressure valve and the second electro-hydraulic proportional pressure valve, thereby realizing the purpose of randomly distributing the pressure ratio of the two partial pressure branches, pushing the load to move, finally realizing the proportional distribution of any pressure, and having wide application range.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
Fig. 2 is a circuit diagram of the proportional control circuit unit according to the present invention.
In the figure: 1. the oil tank, 2, an oil absorption filter, 3, an air filter, 4, a liquid level meter, 5, a fixed displacement pump, 6, a coupler, 7, a motor, 8, a flow divider valve, 9, a first electro-hydraulic proportional pressure valve, 10, a first inductive displacement sensor, 11, a first proportional amplifier, 12, a first stop valve, 13, a second electro-hydraulic proportional pressure valve, 14, a second inductive displacement sensor, 15, a second proportional amplifier, 16, a second stop valve, 17, a proportional control circuit unit, 171, a potentiometer, 172, a subtraction arithmetic unit module, 173, a first following arithmetic unit module, 174 and a second following arithmetic unit module.
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.
As shown in fig. 1 and fig. 2, a hydraulic pressure shunting system with circuit-controlled pressure ratio comprises an oil tank 1, a shunting valve 8, a fixed displacement pump 5, a motor 7 and a proportional control circuit unit 17, wherein the input ends of the oil tank 1, the shunting valve 8 and the motor 7 are all connected with the fixed displacement pump 5, a coupling 6 is connected between the motor 7 and the fixed displacement pump 5, one output end of the shunting valve 8 is respectively connected with a first electro-hydraulic proportional pressure valve 9 and a first stop valve 12, the other output end of the shunting valve 8 is respectively connected with a second electro-hydraulic proportional pressure valve 13 and a second stop valve 16, the input end of the first electro-hydraulic proportional pressure valve 9 is connected with the output end of a first proportional amplifier 11, the input end of the first electro-hydraulic proportional pressure valve 9 is also connected with the reverse input end of the first proportional amplifier 11 through a first inductive displacement sensor 10, the input end of the second electro-hydraulic proportional pressure valve, the input end of the second electro-hydraulic proportional pressure valve 13 is also connected with the reverse input end of a second proportional amplifier 15 through a second inductive displacement sensor 14, and two output branches of a proportional control circuit unit 17 are respectively connected with the homodromous input end of the first proportional amplifier 11 and the homodromous input end of the second proportional amplifier 15; the proportional control circuit unit 17 comprises a potentiometer 171, a moving end of the potentiometer 171 is connected with a reverse input end of a subtraction operator module 172 and a same-direction input end of a first following voltage operator module 173, one fixed end of the potentiometer 171 is connected with a power supply and the same-direction input end of the subtraction operator module 172, the other fixed end of the potentiometer 171 is grounded, an output end of the subtraction operator module 172 is connected with a same-direction input end of a second following voltage operator module 174, and two voltage output branches of the proportional control circuit unit 17 are respectively an output end of the first following voltage operator module 173 and an output end of the second following voltage operator module 174; the oil supply quantity of the constant delivery pump 5 is a constant value, an oil suction filter 2 is connected between an oil inlet of the constant delivery pump 5 and the oil tank 1, and an air filter 3 and a liquid level meter 4 are arranged on the oil tank 1.
In this embodiment, one branch of the two input branches of the subtraction operator module 172 in the proportional control circuit unit 17 has a voltage U, and the other branch is controlled by the potentiometer 1711The output voltage of the subtractor module 172 is U2＝U-U1From fig. 2, it can be seen that the voltages of the two output branches of the proportional control circuit unit 17 are respectively U1And U2，U1And U2And a set constant value of U, since U1The value of (d) is linear with the displacement of the potentiometer 171 brush, the ratio of the voltages through the two output branches is:
in the formula, L1The displacement of the brush of the potentiometer 171, L the length of the resistor of the potentiometer 171, and K the voltage ratio of the two output branches of the proportional control circuit unit 17.
From the above formula, one can obtain: the purpose of voltage arbitrary proportion distribution of two output branches of the proportional control circuit unit can be realized by controlling the displacement of the potentiometer 171, the first following voltage operator module 173 and the second following voltage operator module 174 play roles of buffering, isolating and improving the carrying capacity, and can play a role of impedance matching in the circuit, so that the next-stage amplifying circuit can work better.
Two output branches of a proportional control circuit unit 17 are respectively connected with a homodromous input end of a first proportional amplifier 11 and a homodromous input end of a second proportional amplifier 15, the first proportional amplifier 11 and the second proportional amplifier 15 respectively output corresponding control currents, electromagnet push rods of a first electro-hydraulic proportional pressure valve 9 and a second electro-hydraulic proportional pressure valve 13 respectively output electromagnetic forces proportional to voltage, the electromagnetic forces act on a cone valve core of the first electro-hydraulic proportional pressure valve 9 and a cone valve core of the second electro-hydraulic proportional pressure valve 13 through force transmission springs respectively, meanwhile, a first inductive displacement sensor 10 and a second inductive displacement sensor 14 respectively detect actual positions of electromagnet armature push rods of the first electro-hydraulic proportional pressure valve 9 and the second electro-hydraulic proportional pressure valve 13 and perform negative feedback to the corresponding first proportional amplifier 11 and the second proportional amplifier 15, and an error signal obtained by comparing feedback voltage with set voltage is used for controlling the displacement of an armature, the closed-loop control of the armature position is formed in the valve, the influence of interference such as friction force can be eliminated by utilizing the closed-loop control of displacement, the spring seat can be ensured to have a certain position which is in direct proportion to a man input signal, and an accurate spring compression amount is obtained, so that the accurate control pressure of the pressure valve is obtained.
P1＝K1U1P2＝K1U2
In the formula: p1Regulating the pressure of the branch, P, for the first electro-hydraulic proportional pressure valve 92Regulating the pressure of the branch, K, for the second electrohydraulic proportional pressure valve 131For controlling the proportional relationship between pressure and input signal by means of electro-hydraulic proportional pressure valves, L1L is the length of the resistor of the potentiometer 171, and K is the voltage ratio of the two output branches of the proportional control circuit unit 17.
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 (2)
1. The utility model provides a hydraulic pressure reposition of redundant personnel system of circuit control pressure proportion, includes oil tank, flow divider, constant delivery pump, motor, its characterized in that: the proportional control circuit unit is also included, the oil tank, the input end of the diverter valve and the motor are all connected with the constant delivery pump, a coupler is connected between the motor and the constant delivery pump, one output end of the diverter valve is respectively connected with a first electro-hydraulic proportional pressure valve and a first stop valve, the other output end of the diverter valve is respectively connected with a second electro-hydraulic proportional pressure valve and a second stop valve, the input end of the first electro-hydraulic proportional pressure valve is connected with the output end of a first proportional amplifier, the input end of the first electro-hydraulic proportional pressure valve is also connected with the reverse input end of the first proportional amplifier through a first inductive displacement sensor, the input end of the second electro-hydraulic proportional pressure valve is connected with the output end of a second proportional amplifier, the input end of the second electro-hydraulic proportional pressure valve is also connected with the reverse input end of the second proportional amplifier through, two voltage output branches of the proportional control circuit unit are respectively connected with the homodromous input end of the first proportional amplifier and the homodromous input end of the second proportional amplifier;
the proportional control circuit unit comprises a potentiometer, the moving end of the potentiometer is connected with the reverse input end of the subtraction operator module and the equidirectional input end of the first following voltage operator module, one fixed end of the potentiometer is connected with a power supply and the equidirectional input end of the subtraction operator module, the output end of the subtraction operator module is connected with the equidirectional input end of the second following voltage operator module, two voltage output branches of the proportional control circuit unit are respectively the output end of the first following voltage operator module and the output end of the second following voltage operator module, and the oil supply amount of the constant delivery pump is a constant value;
the voltage ratio of the two output branches of the proportional control circuit unit is as follows:
wherein: u is a branch voltage of two input branches of the subtraction operator module in the proportional control circuit unit, U1The other branch is controlled by a potentiometer, and the output voltage of the subtraction arithmetic module is U2＝U-U1，L1Is the displacement of the potentiometer brush, L isThe length of the resistor body of the potentiometer, K is the voltage ratio of two output branches of the proportional control circuit unit;
the pressure ratio of the pressure of the first electro-hydraulic proportional pressure valve regulating branch to the pressure of the second electro-hydraulic proportional pressure valve regulating branch is as follows:
P1＝K1U1P2＝K1U2
wherein: p1Regulating the pressure of the branch, P, for the first electro-hydraulic proportional pressure valve2Regulating the pressure of the branch for a second electro-hydraulic proportional pressure valve, K1For controlling the proportional relationship between pressure and input signal by means of electro-hydraulic proportional pressure valves, L1The displacement of the potentiometer brush, L the length of the potentiometer resistor body and K the voltage ratio of the two output branches of the proportional control circuit unit;
an oil suction filter is connected between an oil inlet of the constant delivery pump and the oil tank.
2. The hydraulic pressure shunt system of claim 1, wherein: and an air filter and a liquid level meter are arranged on the oil tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810123922.XA CN108331793B (en) | 2018-02-07 | 2018-02-07 | Hydraulic pressure reposition of redundant personnel system of circuit control pressure proportion |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810123922.XA CN108331793B (en) | 2018-02-07 | 2018-02-07 | Hydraulic pressure reposition of redundant personnel system of circuit control pressure proportion |
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| Publication Number | Publication Date |
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| CN108331793A CN108331793A (en) | 2018-07-27 |
| CN108331793B true CN108331793B (en) | 2020-06-26 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101342402A (en) * | 2007-06-29 | 2009-01-14 | 科德曼及舒特莱夫公司 | Programmable shunt with electromechanical valve actuator |
| CN202937530U (en) * | 2012-11-12 | 2013-05-15 | 浙江蓝龙科技有限公司 | Idle stroke advancing flow distribution system of synthetic diamond press |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4582568A (en) * | 1983-09-15 | 1986-04-15 | Beloit Corporation | Apparatus for controlling the consistency of a pulp suspension |
| CN2146024Y (en) * | 1992-12-18 | 1993-11-10 | 浙江大学 | Digital electro-hydraulic ratio control apparatus |
| JP4429997B2 (en) * | 2000-11-30 | 2010-03-10 | 富士通株式会社 | Press machine |
| CN1235032C (en) * | 2004-05-13 | 2006-01-04 | 浙江大学 | Lubricating property testing device for port plate pair of axial plunger pump |
| CN202971383U (en) * | 2013-02-04 | 2013-06-05 | 海特克液压有限公司 | Proportional overflow valve with position feedback |
| CN104405733B (en) * | 2014-09-19 | 2017-10-20 | 江苏大学 | A kind of slider of bender balances electro-hydraulic servo synchronous control system |
| CN106015139B (en) * | 2016-07-20 | 2017-10-31 | 浙江大学 | The tensile and compression testing machine hydraulic loading system of adoption rate overflow valve Differential Control |
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2018
- 2018-02-07 CN CN201810123922.XA patent/CN108331793B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101342402A (en) * | 2007-06-29 | 2009-01-14 | 科德曼及舒特莱夫公司 | Programmable shunt with electromechanical valve actuator |
| CN202937530U (en) * | 2012-11-12 | 2013-05-15 | 浙江蓝龙科技有限公司 | Idle stroke advancing flow distribution system of synthetic diamond press |
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