CN108035945B - Control valve group for quantitative system flow proportion output - Google Patents
Control valve group for quantitative system flow proportion output Download PDFInfo
- Publication number
- CN108035945B CN108035945B CN201810013073.2A CN201810013073A CN108035945B CN 108035945 B CN108035945 B CN 108035945B CN 201810013073 A CN201810013073 A CN 201810013073A CN 108035945 B CN108035945 B CN 108035945B
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- valve
- control valve
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- proportional
- working port
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- 238000013016 damping Methods 0.000 claims description 2
- 238000006073 displacement reaction Methods 0.000 abstract description 13
- 230000007246 mechanism Effects 0.000 abstract description 10
- 150000001875 compounds Chemical class 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 72
- 239000000725 suspension Substances 0.000 description 6
- 239000007788 liquid Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 238000007667 floating Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 239000010720 hydraulic oil Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000010729 system oil Substances 0.000 description 1
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
- 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
- F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
- F15B1/02—Installations or systems with 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
- 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
-
- 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
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention relates to a hydraulic technology, in particular to a control valve group for proportional output of flow of a quantitative system, which comprises a proportional flow control valve, a proportional reversing valve, a pressure compensator, a constant flow valve, a one-way valve, a P oil port, a T oil port, an A1 working port, an A2 working port, a B1 working port and a B2 working port. The valve group realizes the accurate control of the movement speed and displacement of the actuating mechanism by controlling the input signal of the proportional flow control valve, and meanwhile, the movement speed of the actuating mechanism is not influenced by the pressure of the working load; by adjusting the valve port size of each proportional flow control valve, a plurality of execution mechanisms can work simultaneously to complete the compound action without being influenced by load pressure.
Description
Technical Field
The invention relates to a hydraulic technology, in particular to a control valve group for quantitative system flow proportional output.
Background
In practical engineering machinery or industrial hydraulic systems, in order to accurately control output flow, load sensitive variable systems are mostly adopted, but the system has higher cost, harsh use conditions and difficult debugging. The quantitative system is low in price and convenient to maintain and is widely applied, but the control mode mainly adopts bypass throttling, and the output flow is controlled by adjusting the opening of a throttling groove of the valve rod. However, the control mode is obviously affected by load change, and the accurate control of the actuating mechanism is difficult.
Disclosure of Invention
The invention aims to provide a control valve group for quantitative system flow ratio output, which has low cost and high flow control precision.
In order to achieve the aim of the invention, the technical scheme of the invention is as follows: a control valve group for proportional output of flow of a quantitative system comprises a proportional flow control valve, a proportional reversing valve, a pressure compensator, a constant flow valve, a one-way valve, a P oil port, a T oil port, an A1 working port, an A2 working port, a B1 working port and a B2 working port;
the P oil port is respectively communicated with inlets of a proportional flow control valve and a pressure compensator, outlets of the proportional flow control valve are respectively communicated with an A1 working port, an A2 working port, a B1 working port and a B2 working port through one-way valves, the A1 working port, the A2 working port, the B1 working port and the B2 working port are respectively communicated with the T oil port through proportional reversing valves, and a spring cavity of the pressure compensator is communicated with an inlet of a constant flow valve and then takes load signals of the outlets of the proportional flow control valve; the outlet of the pressure compensator and the constant flow valve are communicated with the T oil port, and an overflow valve is arranged between the P oil port and the T oil port.
Preferably, the one-way valve between the outlet of the proportional flow control valve and the working port is a load-holding one-way valve.
Preferably, a damping hole is arranged between the inlet of the constant flow valve and the spring cavity of the pressure compensator.
Preferably, after the pressure compensator is communicated with the inlet of the constant flow valve, an outlet load signal of the proportional flow control valve is assembled through the one-way valve.
Preferably, after the pressure compensator is communicated with the inlet of the constant flow valve, an outlet load signal of the proportional flow control valve is assembled through the shuttle valve.
The invention has the beneficial effects that:
(1) And (3) accurate control of speed displacement of an actuating mechanism: by controlling the input signal of the proportional flow control valve, the accurate control of the movement speed and displacement of the actuating mechanism is realized, and meanwhile, the movement speed of the actuating mechanism is not influenced by the pressure of the working load.
(2) The executing mechanism can compound actions: the oil inlets of the four proportional flow control valves are connected with the oil inlets in parallel, and a plurality of execution mechanisms can work simultaneously by adjusting the valve port size of each proportional flow control valve, so that the compound action is completed, and the influence of load pressure is avoided.
(3) Low pressure unloading: after the actuating mechanism finishes the movement, the oil in the spring cavity controlled by the pressure compensator returns to the oil tank through the constant flow valve, so that the system oil is unloaded through the pressure compensator at low pressure, and the system is more energy-saving.
(4) The quantitative system realizes the accurate control of the output flow, is not influenced by load change, and has low cost, convenient maintenance and wide application range.
Drawings
FIG. 1 is a schematic diagram of a first embodiment of the present invention;
FIG. 2 is a schematic diagram of a second embodiment of the present invention;
fig. 3 is a schematic diagram of the invention applied to an agricultural machine suspension and leveling system.
The figure indicates:
101-proportional flow control valve I, 102-proportional flow control valve II, 103-proportional flow control valve III, 104-proportional flow control valve IV, 105-relief valve, 106-pressure compensator, 107-constant flow valve, 108-proportional reversing valve, 109-one-way valve I, 110-one-way valve II, 111-electronically controlled shut-off valve, 112-one-way valve III, 113-one-way valve IV, 114-electronically controlled shut-off valve, 115-one-way valve V, 116-one-way valve VI, 117-proportional reversing valve, 118-one-way valve VII, 119-one-way valve VIII; 120-shuttle valve I, 121-shuttle valve II, 122-shuttle valve III, and A1 oil port, A2 oil port, B1 oil port, B2 oil port, T oil port and P2 oil port;
1-flow ratio output control valve group I, 2-high pressure filter, 3-hydraulic gear pump, 4-oil absorption filter, 5-liquid level liquid thermometer, 6-hydraulic air filter, 7-hydraulic oil tank, 8-working switching valve group, 9-quick-change connector, 10-clutch control valve, 11-hydraulic clutch, 12-energy accumulator, 13-quick-change connector, 14-flow ratio output control valve group II, 15-car body landing leg oil cylinder, 16-stop valve, 17-emergency manual operation valve group, 18-suspension system right lifting cylinder and 19-suspension system left lifting cylinder.
Detailed Description
For further understanding of the present invention, the following description of the technical solution of the present invention refers to fig. 1 and 2, in conjunction with the accompanying drawings and detailed description.
In this embodiment, as shown in fig. 1, the P2 oil ports of the flow ratio output control valve group are respectively connected with the inlets of the four ratio flow control valves 101/102/103/104, the inlet of the overflow valve 105 and the inlet of the pressure compensator 106; the outlet of the proportional flow control valve 101 is communicated with the inlet of the proportional reversing valve 117 and the A1 oil port through a one-way valve 119, the outlet of the proportional flow control valve 102 is communicated with the inlet of the electric control stop valve 114 and the B1 oil port through a one-way valve 116, and the outlets of the proportional reversing valve 117 and the electric control stop valve 114 are connected to the T1 port; the proportional flow control valve 103 and the proportional flow control valve 104 are connected in a similar manner as before; the outlets of the four proportional flow control valves 101/102/103/104 are communicated with the inlets of the hydraulic control cavity and the constant flow valve 107 of the pressure compensator 106 through the one-way valve 109/112/115/118, and the outlets of the pressure compensator 106 and the constant flow valve 106 are communicated with the port T1.
Taking the invention applied to an agricultural machinery suspension and leveling system as an example, as shown in fig. 2, a gear pump 3 of a quantitative system is connected with a working switching valve group 8 through a high-pressure filter 2, and a Pz1 oil port of the working switching valve group 8 is connected with a Pz2 oil port of a clutch control valve group 10 through a quick-change connector; the A port of the working switching valve group 8 is connected with the P3 port of the vehicle body leveling valve group 14, and the B port is connected with the P2 port of the lifting control valve group 1; the oil ports A3-A6 of the flow ratio output control valve group II14 are respectively connected with a large cavity of the body support leg oil cylinder 15; oil ports B1 and B2 of the lifting control valve group 1 are respectively connected with a large cavity of the lifting oil cylinder, and oil ports A1 and A2 are respectively connected with a small cavity of the lifting oil cylinder; the Az port of the clutch control valve group 10 is connected with a hydraulic clutch 11, the Af port is connected with an energy accumulator 12, and the T port is connected with an oil return tank 7. The flow ratio output control valve group III is used for controlling the suspension lifting oil cylinders, adjusting the expansion and contraction amount of the left lifting oil cylinder and the right lifting oil cylinder, and realizing the self-adaptive adjustment of the cultivation resistance and cultivation posture (height and angle) of the matched farm machinery. The flow ratio output control valve group II14 is used for adjusting the landing leg oil cylinder of the vehicle body, so that the vehicle body level of the tractor is kept on a larger sloping field, and the clutch control valve group 10 controls the hydraulic clutch 11 of the tractor.
The first embodiment and the second embodiment only differ in that the check valve I109, the check valve III112 and the check valve V115 are replaced by the shuttle valve I120, the shuttle valve II 121 and the shuttle valve III 122.
The working principle of the invention is as follows:
when the suspension system is lifted, the movement of the right lifting oil cylinder is taken as an example.
(1) When the oil cylinder lifts, the electromagnet of the proportional flow control valve 104 in the flow proportional output control valve group I is powered on, the opening of a valve port is regulated according to an oil cylinder displacement feedback signal, oil pumped out enters a large cavity of the lifting oil cylinder through the proportional flow control valve 104 and the one-way valve 110, the oil cylinder stretches out, when the oil cylinder moves to a specified displacement, the proportional flow control valve 104 is controlled to be closed by a displacement sensor feedback signal, the movement of the oil cylinder is stopped, and excessive oil pumped in the movement process is unloaded back to the oil tank through the pressure compensator 106; the electromagnet of the electric control stop valve 111 is electrified and works at the right position in the figure, and the small-cavity oil of the hydraulic cylinder returns to the oil tank through the electric control stop valve 111.
(2) When the oil cylinder descends, before the farm tool contacts the ground, the electromagnet of the proportional reversing valve 108 adjusts the opening size of the proportional valve to control the descending speed and displacement of the oil cylinder, at the moment, the electromagnet of the third proportional flow 103 control valve works at the maximum control current, the valve port is fully opened, the pumped oil enters a small cavity of the lifting oil cylinder through the proportional flow control valve 103 and the one-way valve 113, and the oil in the large cavity returns to the oil tank through the proportional reversing valve 108.
(3) When the farm tool is in contact with the ground, the electromagnet of the proportional reversing valve 108 works at the maximum control current, the valve port is fully opened, at the moment, the electromagnet of the proportional flow control valve 103 adjusts the valve port of the proportional valve according to the displacement feedback signal of the oil cylinder, so that the movement displacement and speed of the oil cylinder are controlled, and the pump surplus oil in the movement process is unloaded back to the oil tank through the pressure compensator 106. When the movement of the oil cylinder is finished, all electromagnets are powered off, the load pressure of the oil cylinder is unloaded through the constant flow valve 107, and the pumped oil liquid is unloaded back to the oil tank through the middle position of the three-position four-way electromagnetic directional valve 803.
(4) Floating bit: when the proportional reversing valve 108 and the electric control stop valve 111 in the lifting valve group are powered on simultaneously, the two valves work at the right position in the figure, at the moment, the large cavity and the small cavity of the oil cylinder are communicated, and the system works in a floating state.
(5) When the car body is leveled, the movement of the first oil cylinder from the right in the figure is taken as an example.
The electromagnet of the proportional flow control valve 1401 in the flow proportional output control valve group II14 is powered on, the opening size of the proportional flow control valve is adjusted according to the displacement feedback signal of the landing leg oil cylinder of the vehicle body, the movement displacement of the oil cylinder is controlled, the oil liquid pumped out enters the large cavity of the landing leg oil cylinder through the proportional flow control valve 1401 and the one-way valve 1407, the oil cylinder stretches out, when the oil cylinder moves to the specified displacement, the proportional flow control valve 1401 is controlled to be closed by the feedback signal of the displacement sensor, the movement of the oil cylinder is stopped, and the excess oil liquid pumped in the movement process is unloaded back to the oil tank through the pressure compensator 1403. When the landing leg cylinder descends, the electromagnet of the proportional flow control valve 1401 works at the maximum current, the valve port is fully opened, the electromagnet of the proportional reversing valve 1405 is powered, the size of the valve port is regulated, and the descending speed of the cylinder is controlled.
Claims (5)
1. A control valves for ration system flow ratio output, its characterized in that: the hydraulic control system comprises a proportional flow control valve, a proportional reversing valve, a pressure compensator, a constant flow valve, a one-way valve, a P oil port, a T oil port, an A1 working port, an A2 working port, a B1 working port and a B2 working port;
the P oil port is respectively communicated with inlets of a proportional flow control valve and a pressure compensator, outlets of the proportional flow control valve are respectively communicated with an A1 working port, an A2 working port, a B1 working port and a B2 working port through one-way valves, the A1 working port, the A2 working port, the B1 working port and the B2 working port are respectively communicated with the T oil port through proportional reversing valves, and a spring cavity of the pressure compensator is communicated with an inlet of a constant flow valve and then takes load signals of the outlets of the proportional flow control valve; the outlet of the pressure compensator and the constant flow valve are communicated with the T oil port, and an overflow valve is arranged between the P oil port and the T oil port.
2. The control valve set for metering system flow ratio output of claim 1, wherein: the one-way valve between the outlet of the proportional flow control valve and the working port is a load-holding one-way valve.
3. The control valve set for metering system flow ratio output of claim 1, wherein: and a damping hole is arranged between the inlet of the constant flow valve and the spring cavity of the pressure compensator.
4. The control valve set for metering system flow ratio output of claim 1, wherein: and after the pressure compensator is communicated with an inlet of the constant flow valve, an outlet load signal of the proportional flow control valve is assembled through the one-way valve.
5. The control valve set for metering system flow ratio output of claim 1, wherein: and after the pressure compensator is communicated with the inlet of the constant flow valve, an outlet load signal of the proportional flow control valve is assembled through the shuttle valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810013073.2A CN108035945B (en) | 2018-01-07 | 2018-01-07 | Control valve group for quantitative system flow proportion output |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810013073.2A CN108035945B (en) | 2018-01-07 | 2018-01-07 | Control valve group for quantitative system flow proportion output |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108035945A CN108035945A (en) | 2018-05-15 |
| CN108035945B true CN108035945B (en) | 2024-04-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810013073.2A Active CN108035945B (en) | 2018-01-07 | 2018-01-07 | Control valve group for quantitative system flow proportion output |
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| CN (1) | CN108035945B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110411526B (en) * | 2019-08-14 | 2021-05-14 | 杭州启飞智能科技有限公司 | Method for calculating cumulative dose of plant protection unmanned aerial vehicle |
| CN112985872B (en) * | 2021-05-20 | 2021-08-17 | 成都康拓兴业科技有限责任公司 | Oil mist separation and transportation test bed and test method of aviation oil mist separator |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS646502A (en) * | 1987-06-30 | 1989-01-11 | Hitachi Construction Machinery | Hydraulic circuit apparatus controlled by load sensing |
| CN103671335A (en) * | 2013-12-19 | 2014-03-26 | 杭叉集团股份有限公司 | Load-sensitive electric proportional multi-loop valve |
| CN106032261A (en) * | 2016-07-20 | 2016-10-19 | 浙江大学 | Tension control device of high-power hydraulic winch |
| CN207750316U (en) * | 2018-01-07 | 2018-08-21 | 浙江高宇液压机电有限公司 | Control valve group for the output of quantitative system flow proportional |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2569547B1 (en) * | 2010-05-11 | 2019-03-27 | Parker-Hannificn Corporation | Pressure compensated hydraulic system having differential pressure control |
-
2018
- 2018-01-07 CN CN201810013073.2A patent/CN108035945B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS646502A (en) * | 1987-06-30 | 1989-01-11 | Hitachi Construction Machinery | Hydraulic circuit apparatus controlled by load sensing |
| CN103671335A (en) * | 2013-12-19 | 2014-03-26 | 杭叉集团股份有限公司 | Load-sensitive electric proportional multi-loop valve |
| CN106032261A (en) * | 2016-07-20 | 2016-10-19 | 浙江大学 | Tension control device of high-power hydraulic winch |
| CN207750316U (en) * | 2018-01-07 | 2018-08-21 | 浙江高宇液压机电有限公司 | Control valve group for the output of quantitative system flow proportional |
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| CN108035945A (en) | 2018-05-15 |
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