CN113775585A - Oil inlet and outlet independent control valve and system - Google Patents
Oil inlet and outlet independent control valve and system Download PDFInfo
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- CN113775585A CN113775585A CN202011575012.9A CN202011575012A CN113775585A CN 113775585 A CN113775585 A CN 113775585A CN 202011575012 A CN202011575012 A CN 202011575012A CN 113775585 A CN113775585 A CN 113775585A
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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
- F15B13/021—Valves for interconnecting the fluid chambers of an actuator
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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
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
- F15B11/166—Controlling a pilot pressure in response to the load, i.e. supply to at least one user is regulated by adjusting either the system pilot pressure or one or more of the individual pilot command pressures
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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
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more 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
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
- F15B19/007—Simulation or modelling
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Abstract
The invention belongs to the technical field of hydraulic pressure, and particularly relates to a control valve and a system capable of independently controlling the pressure and the flow of an oil inlet and an oil outlet of an actuator1An oil outlet D of the proportional flow valve communicated with the main oil way1The oil inlet of the proportional overflow valve is communicated with the oil outlet T of the main direction valve, and the oil outlet of the proportional overflow valve is communicated with the oil tank. The plug-in type control valve is adopted to respectively and independently control the pressure and the flow of the inlet and the outlet of the main directional valve, so that the independent control function of the oil inlet and the oil outlet is realized, the control mode is mature, and the large-flow low-pressure loss control is easy to realize;when the flow is small at zero position, the four sides of the main directional valve are linked to throttle to control the flow of the valve port, the control characteristic is good, the structure is simple, and the realization is easy.
Description
Technical Field
The invention belongs to the technical field of hydraulic pressure, and particularly relates to a control valve and a system capable of independently controlling the pressure and flow of an oil inlet and an oil outlet of an actuator.
Technical Field
The existing engineering machinery adopts a multi-way valve to control the movement speed and the direction of an actuator, each throttling edge of the multi-way valve is mechanically and fixedly connected and processed on the same valve core, and when the hydraulic actuator is controlled, oil inlets and oil outlets of the multi-way valve are simultaneously throttled, so that the system is high in energy consumption and generates heat. In order to prevent the flow output by the multi-way valve from being influenced by the change of the load pressure, a pressure compensation valve is required to be arranged at an oil inlet or an oil outlet of the multi-way valve to maintain the constant differential pressure of a valve port of the multi-way valve, and for the working condition exceeding the load, a balance valve or a throttle valve is often additionally arranged to form back pressure, so that the energy efficiency of the system is further reduced due to the pressure loss. In addition, the mode can only control the pressure or flow of one cavity of the actuator at the same time, and the controllability is poor, and the condition is more serious especially under the condition of exceeding the load.
In order to solve the above problems, the existing solution is to apply an independent inlet/outlet control technology to control the pressure and flow of two chambers of an actuator respectively, break through the linkage relationship of the oil inlet/outlet of the traditional control valve, increase the degree of freedom of control, and reduce the pressure loss of the system, and the loop principle of two three-position three-way valves or four two-position two-way valves is often adopted. US katpetler company with US14696869 discloses a loop principle of an oil inlet and outlet independent control system consisting of four sets of displacement force feedback two-way proportional throttle valves, which has been applied to medium and large excavators produced by the company to achieve a good energy-saving effect. However, the structure completely breaks away from the configuration of the multi-way valve for the existing engineering machinery, the design and the research and the development need to be carried out again, the four independently controlled valves are combined to control the same actuator, the whole structure is complex, the manufacturing difficulty is high, and particularly, the displacement force feedback principle is adopted, so that the characteristics of the valve are easily influenced by the feedback spring. No hydraulic enterprise capable of developing related products appears at home, and research work is mainly focused on colleges and universities.
In order to improve the response speed and control precision of the system, in the research of the existing oil inlet and outlet independent control system, a proportional servo valve and a sensor with excellent performance are mostly adopted, and are not compatible with the technology for controlling mature positive and negative flow and machine liquid and electro-hydraulic load, so that the system cannot adapt to the severe operating environment and working requirements of engineering machinery such as an excavator, a loader and the like. US patent No. US13939963, to eaton, discloses an oil inlet and outlet independent control valve configuration using two three-position three-way valves and integrated pressure and spool displacement sensors. Each three-position three-way proportional valve adopts a two-stage structure, a pilot stage adopts a high-frequency ring voice coil motor and a feedback spring rod structure, and an electric closed loop is adopted to control the displacement (opening area) of a main valve core, so that the whole principle is similar to that of a servo valve, and the three-position three-way proportional valve has good control characteristics but is difficult to adapt to the severe operating environment and working requirements of engineering machinery.
Disclosure of Invention
In order to solve the problems, the invention aims to provide the oil inlet and outlet independent control valve and the system which have the advantages of small pressure loss, simple structure, strong compatibility, lower cost and convenience for engineering application, and the matching of the host machine is conveniently realized.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides an oil inlet and outlet port independent control valve, includes main direction valve, I check overflow valve, II check overflow valve, its characterized in that: a proportional flow valve and a proportional overflow valve are further added, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1The oil inlet of the proportional overflow valve is communicated with the oil outlet T of the main direction valve, and the oil outlet of the proportional overflow valve is communicated with the oil tank.
The proportional flow valve comprises a main valve sleeve, a main valve core, a reset spring, a pilot valve, a first pressure sensor, a second pressure sensor, a flow controller, a proportional amplifier and a subtracter,an interpolation controller, a digital flow compensation model, a valve core flow passage L arranged on the main valve core1And a throttling groove CxThe main valve sleeve is provided with a control throttling edge F1The main valve core through shaft is arranged in the main valve sleeve, and the main valve core and the main valve sleeve form a main valve oil inlet C1Main valve oil outlet D1And a main valve control chamber E1Main valve oil inlet C1Through the valve core flow passage L1Communicating throttling groove CxThrottling groove CxControlled throttling edge F1And the main valve control chamber E1Communicating; the pressure sensor is arranged in a control cavity E of the main valve1A communicated cavity, a second pressure sensor is arranged at an oil outlet D of the main valve1A communicating chamber.
The pilot valve comprises a pilot valve core, a pilot valve body, a pilot valve spring and a proportional electromagnet, wherein the pilot valve core is arranged in the pilot valve body; pilot valve oil inlet X1And the main valve control chamber E1Communicated pilot valve oil outlet Y1And the main valve oil outlet D1And (4) communicating.
In the oil inlet and outlet independent control valve, the output signals of the first pressure sensor and the second pressure sensor are connected to a flow controller, the output signal of the flow controller is input to a proportional amplifier, and the proportional amplifier controls the output force of a proportional electromagnet; the flow controller comprises a subtracter, an interpolation controller and a digital flow compensation model.
The proportional flow valve is additionally provided with a pilot valve displacement sensor which is integrated on a proportional electromagnet and detects the displacement and the speed of a pilot valve core by detecting the position of an iron core of the proportional electromagnet, or a through shaft is arranged on the pilot valve core to directly detect the position and the speed of the pilot valve core. The output signal of the flow controller and the output signal of the pilot valve displacement sensor are input into the pilot valve displacement controller together, and the signals are processed by the proportional amplifier to control the output force or displacement of the proportional electromagnet.
The proportional flow valve further integrates a pressure control function and is provided with a third pressure sensor, a pressure controller and a control switch; the III pressure sensor is arranged at an oil inlet C of the proportional flow valve1The output end of the control switch controls the proportional electromagnet through a proportional amplifier, and the proportional flow valve can be selected to control the pressure or flow by switching the position of the control switch.
The oil inlet and outlet independent control valve has the main directional valve oil outlet T which can be set as the proportional flow valve and the proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve is communicated with an oil outlet T of the main directional valve1Is communicated with the oil tank.
The oil inlet and outlet independent control valve is characterized in that the main directional valve comprises: a closed center multi-way reversing valve with a load sensitive detection oil port LS; or an open center multi-way reversing valve with a middle oil way; or a three-position four-way proportional directional valve.
The oil inlet and outlet independent control valve is characterized in that the main directional valve comprises: one of hydraulic control, electric proportional direct control and electro-hydraulic proportional control.
The oil inlet and outlet independent control valve is characterized in that a proportional flow valve is arranged at a port P and/or a port T of a main directional valve, the proportional flow valve comprises a main valve sleeve, a main valve core and a pilot valve, a main valve control cavity is connected with a first pressure sensor, an oil outlet of the main valve is connected with a second pressure sensor, signal output ends of the first pressure sensor and the second pressure sensor are connected with a flow controller, an output signal of the flow controller is input to a proportional amplifier, and the proportional amplifier is connected with and controls a proportional electromagnet;
the method comprises the following steps:
the method comprises the following steps: obtaining a digital flow compensation model of the pilot valve by a test or simulation method;
step two: discretizing a digital flow compensation modelIs formed into
Is stored in the interpolation controller, wherein i is 1, 2, 3 … n; j is 1, 2, 3 … m;
step three: the pressure signals p detected by the I pressure sensor and the II pressure sensorA、pBThe pilot valve port differential pressure delta p is obtained in real time by a subtracter when being input into a flow controller*Input into an interpolation controller while simultaneously converting the desired flow rate qdInputting the interpolation controller;
step four: according to the principle of interpolation
And generating a flow correction signal, and compensating the displacement of the pilot valve electromagnet according to the flow correction signal.
A load sensitive system with independently controlled oil inlet and outlet ports comprises a power source, a load sensitive hydraulic pump, a main safety valve and at least 2 groups of control valves, wherein at least 1 group of control valves is an independent control valve with an oil inlet and outlet port; the power source is coaxially and mechanically connected with the load-sensitive hydraulic pump, the oil outlet of the load-sensitive hydraulic pump is communicated with the main safety valve and the main oil way, the oil inlets of all groups of control valves share the uniform main oil way, and the oil outlets are communicated with the oil tank after being communicated with the uniform oil return way.
The oil inlet and outlet independent control valve is as follows:
the main directional valve is a closed center multi-way reversing valve with a load sensitive detection oil port LS; a proportional flow valve is arranged at the port P of the closed center multi-way reversing valve, and a proportional overflow valve is arranged at the port T; proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve communicated with the main oil way1Is communicated with an oil inlet P of the closed center multi-way reversing valve; an oil inlet of the proportional overflow valve is communicated with an oil return port T of the closed center multi-path reversing valve, and an oil outlet of the proportional overflow valve is communicated with an oil return path.
Or
The main direction valve being a beltThe closed center multi-way reversing valve of the load sensitive detection oil port LS is characterized in that a proportional flow valve is arranged in front of an oil inlet P of the closed center multi-way reversing valve, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1Is communicated with an oil inlet P of the closed center multi-way reversing valve; a proportional flow valve is additionally arranged at the oil return port T of the closed center multi-way reversing valve, the oil inlet of the proportional flow valve is communicated with the oil return port T of the closed center multi-way reversing valve, and the oil outlet of the proportional flow valve is communicated with an oil tank.
A matching system for independently controlling flow of oil inlets and oil outlets comprises a power source, a main hydraulic pump, a main safety valve and at least 2 groups of control valves, wherein at least 1 group of control valves is an independent control valve for the oil inlets and the oil outlets; the power source is coaxially and mechanically connected with the hydraulic pump, the oil outlet of the hydraulic pump is communicated with the main safety valve and the main oil way, the oil inlets of all groups of control valves share the uniform main oil way, and the oil outlets are communicated with the oil tank through the uniform oil return way.
The power source is one of an electric motor and a diesel engine;
the main hydraulic pump is one of a fixed displacement pump and an electric proportional variable displacement pump;
the oil inlet and outlet independent control valve is as follows:
the main directional valve adopts a three-position four-way proportional directional valve, a proportional flow valve is arranged in front of a port P of an oil inlet of the three-position four-way proportional directional valve, and a proportional overflow valve is arranged at a port T; proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve communicated with the main oil way1The three-position four-way proportional directional valve is communicated with an oil inlet P of the three-position four-way proportional directional valve; an oil inlet of the proportional overflow valve is communicated with an oil outlet T of the three-position four-way proportional directional valve, and an oil outlet of the proportional overflow valve is communicated with an oil tank;
or
The main directional valve adopts a three-position four-way proportional directional valve, a proportional flow valve is additionally arranged in front of an oil inlet P of the three-position four-way proportional directional valve, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1The three-position four-way proportional directional valve is communicated with an oil inlet P of the three-position four-way proportional directional valve; a proportional flow valve is arranged at the oil outlet T of the three-position four-way proportional direction valve, the oil inlet of the proportional flow valve is communicated with the oil outlet T of the three-position four-way proportional direction valve, and the proportional flow valveThe oil outlet is communicated with the oil tank.
The utility model provides an oil inlet and outlet port independent control's negative flow system which characterized in that: the system comprises a power source, a negative flow throttling port, a negative flow detection oil way, a negative flow control hydraulic pump, a main safety valve and at least 2 groups of control valves, wherein at least 1 group of the control valves is an independent control valve of an oil inlet and an oil outlet; the power source is coaxially and mechanically connected with the negative flow control hydraulic pump, the oil outlet of the negative flow control hydraulic pump is communicated with the main safety valve and the main oil way, the oil inlets of all groups of control valves share a uniform main oil way, the oil outlets are communicated with the oil tank through a uniform oil return way, the oil outlet F of a neutral oil way of the main directional valve is communicated with a negative flow throttling port and a negative flow detection oil way, the negative flow detection oil way is communicated with a negative flow controller of the negative flow control hydraulic pump, and the negative flow throttling port is communicated with the oil tank.
The oil inlet and outlet independent control valve is as follows:
the main directional valve is an open center multi-way reversing valve with a middle oil way, a proportional flow valve is arranged at an oil inlet P of the open center multi-way reversing valve, and a proportional overflow valve is arranged at an oil outlet T of the open center multi-way reversing valve; proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve communicated with the main oil way1Is communicated with an oil inlet P of the open center multi-way reversing valve; an oil inlet of the proportional overflow valve is communicated with an oil outlet T of the open center multi-path reversing valve, and an oil outlet of the proportional overflow valve is communicated with an oil tank.
Or
The main directional valve is an open center multi-way directional valve with a middle oil way, a proportional flow valve is additionally arranged in front of an oil inlet P of the open center multi-way directional valve, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1The three-position four-way proportional directional valve is communicated with an oil inlet P of the three-position four-way proportional directional valve; a proportional flow valve is arranged at the oil outlet T of the open center multi-way reversing valve, the oil inlet of the proportional flow valve is communicated with the oil outlet T of the open center multi-way reversing valve, and the oil outlet of the proportional flow valve is communicated with an oil tank.
Compared with the prior art, the invention has the following beneficial effects:
the plug-in type control valve is adopted to respectively and independently control the pressure and the flow of the inlet and the outlet of the main directional valve, so that the independent control function of the oil inlet and the oil outlet is realized, the control mode is mature, and the large-flow low-pressure loss control is easy to realize; when the flow is small at zero position, the four sides of the main directional valve are linked to throttle to control the flow of the valve port, the control characteristic is good, the structure is simple, and the realization is easy;
the invention can better match and fuse the existing multi-way valve structure and the electro-hydraulic control technology, can directly match the existing three-position four-way reversing valve, the positive/negative flow and load sensitive multi-way valve and the corresponding system control principle, has good compatibility and lower cost, and has stronger practical engineering application value;
the invention provides an interpolation flow control algorithm of a proportional flow valve, which dynamically adjusts the displacement of a pilot valve core by calculating and detecting the pressure difference of a pilot valve port of the proportional valve and calculating the flow of the pilot valve port, amplifies the flow of a main valve by the flow of the pilot valve, realizes the accurate control of the flow of the valve port under the variable load working condition, and solves the problems of large pressure loss, small through-flow capacity, poor stability and the like caused by the traditional mechanical pressure difference compensator; based on the same structure, the proportional flow valve has a closed-loop safety redundancy function, when components such as a sensor and the like have faults, the proportional flow valve can be automatically converted into internal feedback control, and the system is prevented from being out of control;
the invention can conveniently realize various composite control modes of pressure/flow, pressure/pressure, flow/pressure and the like of the oil inlet and the oil outlet of the multi-way valve by additionally arranging different types of flow control type, pressure control type and composite control type plug-in type control valves at the inlet and the outlet of the main directional valve without complex control algorithms;
the invention can conveniently realize modular design, various cartridge valves can be replaced in situ, the same system can be arranged differently according to the working conditions and action requirements of different actuators, the combination form of inlet and outlet plug-in control valves of different types is adopted pertinently, and the control can be carried out according to the function of the main directional valve without installing the cartridge valves.
Drawings
FIG. 1 is a schematic diagram of a first structure of an independent control valve of an oil inlet and an oil outlet according to the present invention;
FIG. 2 is a schematic view of a second construction principle and a control method of the proportional flow valve of the present invention;
FIG. 3 is a schematic diagram of a second structure of the independent control valve for the oil inlet and the oil outlet according to the present invention;
FIG. 4 is a schematic diagram of a third structure of the independent control valve for the oil inlet and the oil outlet according to the present invention;
FIG. 5 is a schematic diagram of the present invention applied to a load sensitive system;
FIG. 6 is a schematic diagram of the flow matching system of the present invention;
fig. 7 is a schematic diagram of the negative flow control system of the present invention.
In the figure, 1-main direction valve, 2-I one-way overflow valve, 3-II one-way overflow valve, 5-proportion overflow valve, 27-power source, 28-load sensitive hydraulic pump, 29-main safety valve, 30-main oil circuit, 31-oil return circuit, 32-shuttle valve, 33-I group multi-way valve, 34-II group multi-way valve, 35-III group multi-way valve, 36-hydraulic cylinder, 37-hydraulic motor, 38-I proportion pressure reducing valve, 39-II proportion pressure reducing valve, 40-negative flow throttling opening, 41-negative flow detection oil circuit, 42-main hydraulic pump, 43-negative flow control hydraulic pump, A-I working oil opening, B-II working oil opening, P-main direction valve oil inlet, T-main direction valve oil outlet, the oil inlet of the E-middle oil way and the oil outlet of the F-middle oil way are connected with the LS-load sensitive detection oil port;
4-a proportional flow valve comprising: 7-main valve sleeve, 8-main valve core, 9-reset spring, 10-pilot valve, 11-pilot valve core, 12-pilot valve body, 13-pilot valve spring, 14-proportional electromagnet, 15-first pressure sensor, 16-second pressure sensor, 17-flow controller, 18-proportional amplifier, 19-subtracter, 20-interpolation controller, 21-digital flow compensation model, 22-pilot valve displacement sensor, 23-pilot valve displacement controller, 24-third pressure sensor, 25-pressure controller, 26-control switch, C1Proportional flow valve oil inlet, D1Proportional flow valve outlet port, X1-pilot valve oil inlet, Y1-pilot valve oil outlet, L1-a spool flow passage, CxA throttling groove, E1Main valve control chamber, F1-controlling the throttling edge.
Detailed Description
FIG. 1 shows a first structural principle of the independent control valve of oil inlet and outlet of the present invention, which comprisesThe check overflow valve comprises a main directional valve 1, an I-th check overflow valve 2 and an II-th check overflow valve 3, wherein an I-th working oil port A of the main directional valve 1 is communicated with the I-th check overflow valve 2, and an II-th working oil port B of the main directional valve 1 is communicated with the II-th check overflow valve 3; the main directional valve 1 adopts a hydraulically controlled closed center multi-way reversing valve with a load sensitive detection oil port LS, a proportional flow valve 4 is additionally arranged in front of an oil inlet P of the main directional valve 1, and an I main valve oil inlet C of the flow amplification proportional flow valve 41An oil outlet D of a first main valve communicated with the main oil way1Is communicated with an oil inlet P of the main directional valve; a proportional overflow valve 5 is additionally arranged behind an oil outlet T of the main direction valve 1, an oil inlet of the proportional overflow valve 5 is communicated with an oil return port T of the main direction valve, and an oil outlet of the proportional overflow valve 5 is communicated with an oil tank.
As shown in fig. 1, the proportional flow valve 4 comprises: the main valve sleeve 7, the main valve core 8, the reset spring 9 and the pilot valve 10; a valve core flow passage L is additionally arranged on the main valve core 81And a throttling groove Cx(ii) a The main valve core 8 is arranged in the main valve sleeve 7 and forms a main valve oil inlet C with the main valve sleeve 71Main valve oil outlet D1And a main valve control chamber E1Main valve oil inlet C1Through the valve core flow passage L1Communicating throttling groove CxThrottling groove CxAnd the main valve control chamber E1Connected, main valve control chamber E1With pilot valve oil inlet X1Communicated pilot valve oil outlet Y1And the main valve oil outlet D1And (4) communicating. The pilot valve 10 comprises: the pilot valve comprises a pilot valve core 11, a pilot valve body 12, a pilot valve spring 13 and a first proportion electromagnet 14; the pilot valve spool 11 is arranged in the pilot valve body 12, one end of a pilot valve spring 13 acts on the pilot valve body 12, the other end acts on the pilot valve spool 11, the proportional electromagnet 14 is connected with the pilot valve body 12, and an armature of the proportional electromagnet 14 acts on the other end face of the pilot valve spool 12.
The proportional flow valve 4 adopts an interpolation flow control method, and is additionally provided with a first pressure sensor 15, a second pressure sensor 16, a flow controller 17 and a proportional amplifier 18; the I pressure sensor 15 and the II pressure sensor 16 are respectively connected with the pilot valve oil inlet and the main valve oil outlet D1Communicate and detect the pressure signal pA、pBInput flow controller 1In the step 7, after the operation processing of the flow controller 17, the proportional electromagnet 14 is controlled through a proportional amplifier 18; the flow controller 17 includes a subtractor 19, an interpolation controller 20, and a digital flow compensation model 21.
The specific control method comprises the following steps: the digital flow compensation model 21 of the pilot valve is obtained by a test or simulation method, namely
The curve model, wherein the X axis is a flow compensation control signal, the Y axis is the square root of the pressure difference of the main valve, and the Z axis is output flow; the digital flow compensation model 21 is then discretized and the method
Is stored in the interpolation controller 20, where i is 1, 2, 3 … n; j is 1, 2, 3 … m;
then the pressure signals p detected by the I pressure sensor 15 and the II pressure sensor 16 are measuredA、pBThe real-time pilot valve differential pressure Deltap is obtained by a subtracter 19 when the pilot valve differential pressure Deltap is input into a flow controller 17*Input into the interpolation controller 20 while simultaneously applying the desired flow rate qdInput to the interpolation controller 20, based on the interpolation principle
The flow correction signal is calculated, the displacement of the electromagnet of the pilot valve 10 can be compensated by controlling the flow correction control signal, and the compensation of the displacement of the pilot valve 10 can be fed back to the flow of the main valve according to the displacement-flow compensation principle of the flow amplification type valve, so that the flow compensation function of the main valve is realized.
Fig. 2 shows a second design principle and a control method of the proportional flow valve 4. The proportional flow valve 4 is further provided with a pilot displacement sensor 22, the pilot displacement sensor 22 is connected with the proportional electromagnet 14, a feedback signal of the pilot displacement sensor 22 is input into a pilot valve core displacement controller 23 and passes through the pilot valve core displacement controllerAfter processing 23, the I proportion electromagnet 14 is controlled in a closed loop mode. The proportional flow valve 4 further integrates a pressure control function, and is additionally provided with a third pressure sensor 24, a pressure controller 25 and a control switch 26; third pressure sensor 24 and proportional flow valve 4 main valve oil inlet C1And signal output ends of the II pressure sensor 16 and the III pressure sensor 17 are connected with a pressure controller 25, output ends of the pressure controller 25 and the flow controller 17 are connected with an input end of a control switch 26, and an output end of the control switch 26 controls the proportional electromagnet 14 through a proportional amplifier 18. By switching the control switch 26, the proportional flow valve 4 can be selected for pressure control or flow control.
Fig. 3 shows a second structural principle of the oil inlet and outlet independent control valve of the present invention, which is different from fig. 1 in that the main directional valve 1 adopts an electric proportional control three-position four-way directional valve.
FIG. 4 shows a third structural principle of the oil inlet and outlet independent control valve of the present invention, which is different from FIG. 1 in that the main directional valve 1 adopts an open center multi-way directional valve with a neutral oil path controlled by a first proportional pressure reducing valve 38 and a second proportional pressure reducing valve 39, and integrates a flow regeneration function, a proportional flow valve 4 is additionally arranged behind an oil outlet T of the main directional valve 1, and an oil inlet C of the proportional flow valve 41An oil return port D communicated with an oil return port T of the main directional valve 1 and provided with a proportional flow valve 41Is communicated with the oil tank.
The first embodiment is as follows:
fig. 5 shows a principle of a load-sensitive system using the independent control valves of the oil inlet and the oil outlet in fig. 1, and the load-sensitive system includes a power source 27, a load-sensitive hydraulic pump 28, a main safety valve 29, and 3 sets of multi-way valves, wherein the multi-way valves share a uniform main oil path 30 and are communicated with an oil tank through a uniform oil return path 31. The oil outlet of the load sensitive hydraulic pump 28 is communicated with a main safety valve 29 and a main oil path 30, and an oil return path 31 is communicated with an oil tank. The first group of multi-way valves 33 are independent control valves of an oil inlet and an oil outlet, and are different from the independent control valves of the oil inlet and the oil outlet shown in fig. 1 in that a proportional flow valve arranged in front of an oil inlet P of a main directional valve 1 is integrated with a pressure control function, and an oil return port T of the main directional valve 1 is also additionally provided with a proportional flow valve integrated with the pressure control function; the second set of multiplex valves 34 are conventional load sensitive multiplex valves; the third group of multi-way valves are independent control valves of oil inlet and outlet ports, and are the same as the independent control valves of the oil inlet and outlet ports shown in the figure 1 in connection relation and composition structure.
The power source 27 is one of an internal combustion engine, a three-phase asynchronous motor, a variable frequency motor and a servo motor.
Example two:
fig. 6 shows a flow matching system principle using the independent control valves of the oil inlet and outlet shown in fig. 4, which includes a power source 27, a hydraulic pump 42, a main safety valve 29, 3 sets of multi-way valves, a first set of multi-way valves 33, a second set of multi-way valves 34, and a third set of multi-way valves 35, which are arranged in sequence from left to right, and all the independent control valves of the oil inlet and outlet share a unified main oil path 30 and are communicated with an oil tank through a unified oil return path 31. The power source 27 is a servo motor, the hydraulic pump 42 is a fixed displacement pump, an oil outlet of the hydraulic pump 42 is communicated with the main safety valve 29 and the main oil path 30, and an oil outlet of the main safety valve 29 and the oil return path 31 are communicated with an oil tank. The first group of multi-way valves 33 and the third group of multi-way valves 34 are independent control valves of oil inlet and outlet, and the second group of multi-way valves 35 are three-position four-way proportional valves.
The third group of the multi-way valves 35 are the same as the oil inlet and outlet independent control valves shown in fig. 4 in connection relationship and composition structure. The first group of the multi-way valve 33 is different from the oil inlet and outlet independent control valve shown in fig. 4 in that a proportional flow valve 4 is arranged behind the oil outlet T of the main directional valve 1, and the first main valve oil inlet C of the proportional flow valve 41An oil outlet D of a first main valve is communicated with an oil return port T of the main directional valve1And communicates with the oil return passage 31.
Example three:
fig. 7 shows a negative flow control system formed by applying the oil inlet/outlet independent control valves shown in fig. 5, which includes a power source 27, a negative flow control hydraulic pump 43, a main safety valve 29 and 3 sets of multi-way valves, from bottom to top, a first set of multi-way valves 33, a second set of multi-way valves 34, a third set of multi-way valves 35, the first set of multi-way valves 33, the second set of multi-way valves 34, and the third set of multi-way valves 35 are oil inlet/outlet independent control valves, and all the associated oil inlet/outlet independent control valves share a uniform main oil path 30 and are communicated with an oil tank through a uniform oil return path 31.
Wherein, the power source 27 is a diesel engine, the oil outlet of the negative flow control hydraulic pump 43 is communicated with the main safety valve 29 and the main oil path 30, and the oil return path 31 is communicated with the oil tank.
The first group of multi-way valves 33 have the same connection relationship and composition structure as the inlet and outlet independent control valves shown in fig. 7, a neutral oil path oil inlet E of the main directional valve 1 is communicated with an oil outlet of the negative flow control hydraulic pump 43, and a neutral oil path oil outlet F of the main directional valve 1 is communicated with a neutral oil path oil inlet E of the directional valve in the second multi-way valve 34.
The second group of multi-way valves 34 is different from the inlet and outlet independent control valve shown in fig. 7 in that a proportional overflow valve 5 is additionally arranged behind an oil outlet T of the main directional valve 1, an oil inlet of the proportional overflow valve 5 is communicated with an oil return port T of the main directional valve, an oil outlet of the proportional overflow valve 5 is communicated with an oil return path 31, and an oil outlet F of a neutral oil path in the main directional valve 1 is communicated with an oil inlet E of a neutral oil path in a directional valve in a tail valve group 53.
The group III multiway valve 35 is different from the independent inlet and outlet control valve shown in FIG. 7 in that a proportional flow valve 4 additionally arranged behind an oil return port T of the main directional valve 1 integrates a pressure control function; an oil outlet F of a middle oil way of the main directional valve 1 is communicated with a negative flow throttling port 40 and a negative flow detection oil way 41, the negative flow detection oil way 41 is communicated with a negative flow controller of a negative flow control hydraulic pump 43, and the negative flow throttling port 40 is communicated with an oil tank.
The foregoing merely illustrates several embodiments of the invention, which are described in greater detail and detail, and not to limit the scope of the invention. The present invention is not limited to the above-described circuit, and may be applied to other multi-actuator construction machines such as an excavator, a loader, a crane, and a telescopic arm forklift.
Claims (10)
1. The utility model provides an oil inlet and outlet independent control valve, includes main directional valve (1), I check overflow valve (2), II check overflow valve (3), its characterized in that: a proportional flow valve (4), a proportional overflow valve (5) and a proportional flow valve oil inlet C are further added1An oil outlet D of the proportional flow valve communicated with the main oil path (30)1Is communicated with an oil inlet P of the main direction valve, an oil inlet of the proportional overflow valve is communicated with an oil outlet T of the main direction valve, and an oil outlet of the proportional overflow valve is connected with an oil tankOpening;
the proportional flow valve comprises a main valve sleeve (7), a main valve core (8), a reset spring (9), a pilot valve (10), a first pressure sensor (15), a second pressure sensor (16), a flow controller (17), a proportional amplifier (18), a subtracter (19), an interpolation controller (20) and a digital flow compensation model (21), wherein a valve core flow channel L is arranged on the main valve core1And a throttling groove CxThe main valve sleeve is provided with a control throttling edge F1The main valve core through shaft is arranged in the main valve sleeve, and the main valve core and the main valve sleeve form a main valve oil inlet C1Main valve oil outlet D1And a main valve control chamber E1Main valve oil inlet C1Through the valve core flow passage L1Communicating throttling groove CxThrottling groove CxControlled throttling edge F1And the main valve control chamber E1Communicating; the pressure sensor (15) is arranged in a control cavity E of the main valve1A communicated cavity, a second pressure sensor (16) is arranged at an oil outlet D of the main valve1A communicating chamber;
the pilot valve (10) comprises a pilot valve core (11), a pilot valve body (12), a pilot valve spring (13) and a proportional electromagnet (14), wherein the pilot valve core is arranged in the pilot valve body, one end of the pilot valve spring acts on the pilot valve body, the other end of the pilot valve spring acts on the pilot valve core, the proportional electromagnet is connected with the pilot valve body, and an armature of the proportional electromagnet controls the displacement of the pilot valve core; pilot valve oil inlet X1And the main valve control chamber E1Communicated pilot valve oil outlet Y1And the main valve oil outlet D1Communicating;
the output signals of the first pressure sensor and the second pressure sensor are connected to a flow controller (17), the output signal of the flow controller is input to a proportional amplifier (18), and the proportional amplifier controls the output force of a proportional electromagnet; the flow controller comprises a subtracter (19), an interpolation controller (20) and a digital flow compensation model (21).
2. The oil inlet and outlet independent control valve as claimed in claim 1, wherein: the proportional flow valve is further additionally provided with a pilot valve displacement sensor (22), the pilot valve displacement sensor is integrated on the proportional electromagnet, and the displacement and the speed of the pilot valve core are detected by detecting the position of an iron core of the proportional electromagnet, or a through shaft is arranged on the pilot valve core to directly detect the position and the speed of the pilot valve core; the output signal of the flow controller and the output signal of the pilot valve displacement sensor are input into a pilot valve displacement controller (23) together, and the signals are processed by a proportional amplifier to control the output force or displacement of the proportional electromagnet.
3. The oil inlet/outlet independent control valve according to claim 1 or 2, wherein: the proportional flow valve further integrates a pressure control function and is provided with a III pressure sensor (24), a pressure controller (25) and a control switch (26); the III pressure sensor is arranged at an oil inlet C of the proportional flow valve1The signal output ends of the II and III pressure sensors are connected to a pressure controller, the output signals of the pressure controller and a flow controller are connected to the input end of a control switch (26), the output end of the control switch controls a proportional electromagnet through a proportional amplifier, and the proportional flow valve can be selected to control the pressure or flow through switching the position of the control switch.
4. The oil inlet and outlet independent control valve as claimed in claim 1, wherein: the oil outlet T of the main directional valve can also be set as the proportional flow valve, and the oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve is communicated with an oil outlet T of the main directional valve1Is communicated with the oil tank.
5. The oil inlet/outlet independent control valve as claimed in claim 1 or 4, wherein: the main direction valve is as follows: a closed center multi-way reversing valve with a load sensitive detection oil port LS;
or an open center multi-way reversing valve with a middle oil way;
or a three-position four-way proportional directional valve.
6. The oil inlet/outlet independent control valve as claimed in claim 1 or 4, wherein: the main direction valve is as follows: one of hydraulic control, electric proportional direct control and electro-hydraulic proportional control.
7. An oil inlet and outlet independent control valve is characterized in that: a proportional flow valve (4) is arranged at the port P and/or the port T of the main directional valve, the proportional flow valve (4) comprises a main valve sleeve, a main valve core and a pilot valve, a control cavity of the main valve is connected with a first pressure sensor, an oil outlet of the main valve is connected with a second pressure sensor, signal output ends of the first pressure sensor and the second pressure sensor are connected with a flow controller, an output signal of the flow controller is input to a proportional amplifier, and the proportional amplifier is connected with and controls the proportional electromagnet;
the method comprises the following steps:
the method comprises the following steps: obtaining a digital flow compensation model of the pilot valve by a test or simulation method;
step two: discretizing the digital flow compensation model and calculating the flow compensation model
Is stored in the interpolation controller, wherein i is 1, 2, 3 … n; j is 1, 2, 3 … m;
step three: the pressure signals p detected by the I pressure sensor and the II pressure sensorA、pBThe pilot valve port differential pressure delta p is obtained in real time by a subtracter when being input into a flow controller*Input into an interpolation controller while simultaneously converting the desired flow rate qdInputting the interpolation controller;
step four: according to the principle of interpolation
And generating a flow correction signal, and compensating the displacement of the pilot valve electromagnet according to the flow correction signal.
8. The utility model provides a sensitive system of hydraulic fluid port independent control load which characterized in that: the hydraulic control system comprises a power source (27), a load-sensitive hydraulic pump (28), a main safety valve (29) and at least 2 groups of control valves, wherein at least 1 group of the control valves is an oil inlet/outlet independent control valve; the power source is coaxially and mechanically connected with the load-sensitive hydraulic pump, the oil outlet of the load-sensitive hydraulic pump is communicated with the main safety valve and the main oil way (30), the oil inlets of all groups of control valves share a uniform main oil way, and the oil outlet is communicated with the oil tank after being communicated with a uniform oil return way (31);
the oil inlet and outlet independent control valve is as follows:
the main directional valve is a closed center multi-way reversing valve with a load sensitive detection oil port LS; a proportional flow valve is arranged at the port P of the closed center multi-way reversing valve, and a proportional overflow valve is arranged at the port T; proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve communicated with the main oil way1Is communicated with an oil inlet P of the closed center multi-way reversing valve; an oil inlet of the proportional overflow valve is communicated with an oil return port T of the closed center multi-path reversing valve, and an oil outlet of the proportional overflow valve is communicated with an oil return path;
or
The main directional valve is a closed center multi-way reversing valve with a load sensitive detection oil port LS, a proportional flow valve is arranged in front of an oil inlet P of the closed center multi-way reversing valve, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1Is communicated with an oil inlet P of the closed center multi-way reversing valve; a proportional flow valve is additionally arranged at the oil return port T of the closed center multi-way reversing valve, the oil inlet of the proportional flow valve is communicated with the oil return port T of the closed center multi-way reversing valve, and the oil outlet of the proportional flow valve is communicated with an oil tank.
9. The utility model provides an oil inlet and outlet independent control flow matching system which characterized in that: the hydraulic pump comprises a power source, a main hydraulic pump (42), a main safety valve and at least 2 groups of control valves, wherein at least 1 group of the control valves are independent control valves of an oil inlet and an oil outlet; the power source is coaxially and mechanically connected with the hydraulic pump, the oil outlet of the hydraulic pump is communicated with the main safety valve and the main oil way, the oil inlets of all groups of control valves share a uniform main oil way, and the oil outlets are communicated with the oil tank through a uniform oil return way;
the power source is one of an electric motor and a diesel engine;
the main hydraulic pump is one of a fixed displacement pump and an electric proportional variable displacement pump;
the oil inlet and outlet independent control valve is as follows:
the main directional valve adopts a three-position four-way proportional directional valve, a proportional flow valve is arranged in front of a port P of an oil inlet of the three-position four-way proportional directional valve, and a proportional overflow valve is arranged at a port T; proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve communicated with the main oil way1The three-position four-way proportional directional valve is communicated with an oil inlet P of the three-position four-way proportional directional valve; an oil inlet of the proportional overflow valve is communicated with an oil outlet T of the three-position four-way proportional directional valve, and an oil outlet of the proportional overflow valve is communicated with an oil tank;
or
The main directional valve adopts a three-position four-way proportional directional valve, a proportional flow valve is additionally arranged in front of an oil inlet P of the three-position four-way proportional directional valve, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1The three-position four-way proportional directional valve is communicated with an oil inlet P of the three-position four-way proportional directional valve; a proportional flow valve is arranged at the oil outlet T of the three-position four-way proportional direction valve, the oil inlet of the proportional flow valve is communicated with the oil outlet T of the three-position four-way proportional direction valve, and the oil outlet of the proportional flow valve is communicated with an oil tank.
10. The utility model provides an oil inlet and outlet port independent control's negative flow system which characterized in that: the system comprises a power source, a negative flow throttling port (40), a negative flow detection oil way (41), a negative flow control hydraulic pump (43), a main safety valve and at least 2 groups of control valves, wherein at least 1 group of the control valves is an oil inlet/outlet independent control valve; the power source is coaxially and mechanically connected with the negative flow control hydraulic pump, the oil outlet of the negative flow control hydraulic pump is communicated with the main safety valve and the main oil way, the oil inlets of all groups of control valves share a uniform main oil way (30), the oil outlet is communicated with the oil tank through a uniform oil return way, the oil outlet F of a neutral oil way of the main directional valve is communicated with a negative flow throttling port and a negative flow detection oil way, the negative flow detection oil way is communicated with a negative flow control hydraulic pump negative flow controller, and the negative flow throttling port is communicated with the oil tank;
the oil inlet and outlet independent control valve is as follows:
the main direction valve having a neutral oil pathThe oil inlet P of the open center multi-way reversing valve is provided with a proportional flow valve, and the oil outlet T of the open center multi-way reversing valve is provided with a proportional overflow valve; proportional flow valve oil inlet C1An oil outlet D of the proportional flow valve communicated with the main oil way1Is communicated with an oil inlet P of the open center multi-way reversing valve; an oil inlet of the proportional overflow valve is communicated with an oil outlet T of the open central multi-path reversing valve, and an oil outlet of the proportional overflow valve is communicated with an oil tank;
or
The main directional valve is an open center multi-way directional valve with a middle oil way, a proportional flow valve is additionally arranged in front of an oil inlet P of the open center multi-way directional valve, and an oil inlet C of the proportional flow valve1An oil outlet D of the proportional flow valve communicated with the main oil way1The three-position four-way proportional directional valve is communicated with an oil inlet P of the three-position four-way proportional directional valve; a proportional flow valve is arranged at the oil outlet T of the open center multi-way reversing valve, the oil inlet of the proportional flow valve is communicated with the oil outlet T of the open center multi-way reversing valve, and the oil outlet of the proportional flow valve is communicated with an oil tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011575012.9A CN113775585A (en) | 2020-12-28 | 2020-12-28 | Oil inlet and outlet independent control valve and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011575012.9A CN113775585A (en) | 2020-12-28 | 2020-12-28 | Oil inlet and outlet independent control valve and system |
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| Publication Number | Publication Date |
|---|---|
| CN113775585A true CN113775585A (en) | 2021-12-10 |
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ID=78835347
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011575012.9A Pending CN113775585A (en) | 2020-12-28 | 2020-12-28 | Oil inlet and outlet independent control valve and system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115681262A (en) * | 2022-10-27 | 2023-02-03 | 华东交通大学 | Load-sensitive electro-hydraulic conversion oil inlet module |
| CN116181727A (en) * | 2023-02-23 | 2023-05-30 | 湖州生力液压有限公司 | Energy-saving type electric control multi-way valve with proportion |
-
2020
- 2020-12-28 CN CN202011575012.9A patent/CN113775585A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115681262A (en) * | 2022-10-27 | 2023-02-03 | 华东交通大学 | Load-sensitive electro-hydraulic conversion oil inlet module |
| CN116181727A (en) * | 2023-02-23 | 2023-05-30 | 湖州生力液压有限公司 | Energy-saving type electric control multi-way valve with proportion |
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