CN114542549A - High-precision pressure regulating loop - Google Patents
High-precision pressure regulating loop Download PDFInfo
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- CN114542549A CN114542549A CN202210146291.XA CN202210146291A CN114542549A CN 114542549 A CN114542549 A CN 114542549A CN 202210146291 A CN202210146291 A CN 202210146291A CN 114542549 A CN114542549 A CN 114542549A
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- 230000001105 regulatory effect Effects 0.000 title claims abstract description 47
- 238000012360 testing method Methods 0.000 claims abstract description 19
- 238000004891 communication Methods 0.000 claims description 3
- 238000006073 displacement reaction Methods 0.000 claims description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
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- 238000010586 diagram Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
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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
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
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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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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Fluid Pressure (AREA)
Abstract
The invention relates to a high-precision pressure regulating loop, which is used in a hydraulic proportional valve test bench, and comprises: parallelly connected high-pressure proportion overflow valve, low pressure proportion overflow valve and proportion choke valve, the pressure control circuit still includes: and the electromagnetic switch valve is used for adjusting the pressure adjusting requirements of different pressure grades through switching of the electromagnetic switch valve. According to the high-precision pressure regulating circuit provided by the invention, the high-precision pressure regulating requirement of more than 0.5% within the range of 0-30MPa can be realized by connecting the high-pressure proportional overflow valve, the low-pressure proportional overflow valve and the proportional throttle valve in parallel with the pressure regulating circuit, so that the testing requirements of proportional valves with different pressure grades are met.
Description
Technical Field
The invention relates to the technical field of hydraulic pressure, in particular to a high-precision pressure regulating loop.
Background
In test tests of steady-state flow characteristics, throttling characteristics, load characteristics and the like of the hydraulic proportional valve, the inlet pressure of the tested valve needs to be accurately adjusted. In order to meet the requirement of testing precision in national standards, the inlet pressure regulation precision and range have higher requirements. The traditional technical method adopts a high-pressure proportional overflow valve for regulation so as to meet the test requirement of the high-pressure proportional valve, and the pressure regulation range is large.
However, because the minimum regulating pressure of the regulating mode of the traditional high-pressure proportional overflow valve is higher and the pressure regulating precision is lower, when the low-pressure proportional valve is tested, the problems of insufficient pressure regulating range and lower regulating precision exist. In order to meet the requirement of high-precision inlet pressure regulation during the test of the high-low pressure proportional valve, the inlet pressure regulation loop of the tested valve with wide range and high precision is urgently required to be developed.
Disclosure of Invention
The problem of exist among the prior art because the minimum regulation pressure of traditional high pressure proportional overflow valve regulation mode is higher, and pressure regulation precision is lower, when testing the low pressure proportional valve, have that the pressure control range is not enough and the regulation precision is lower is solved in order to solve.
The invention mainly aims to provide a pressure regulating loop at an inlet of a tested proportional valve, which has wide pressure regulating range and high pressure regulating precision, is used in a high-performance proportional valve testing experiment table, and can meet the requirements of wide regulating range and high pressure regulating precision required by high-low pressure proportional valve testing.
The technical scheme provided by the invention is as follows:
a high precision pressure regulation circuit for use in a hydraulic proportional valve test stand, the pressure regulation circuit comprising: the high-pressure proportional overflow valve, the low-pressure proportional overflow valve and the proportional throttle valve are connected in parallel with the pressure regulating loop; the pressure regulating circuit further comprises: an electromagnetic on-off valve; and the switching of the electromagnetic switch valve is controlled to adjust the pressure adjusting requirements of different pressure grades.
In some embodiments, when the pressure range is 15-30MPa, switching to the high-pressure proportional relief valve for pressure regulation; when the pressure range is 2-15MPa, switching to the low-pressure proportional overflow valve for pressure regulation; and when the pressure range is below 2MPa, switching to the proportional throttle valve for pressure regulation.
In some embodiments, the pressure regulation circuit further comprises: a first solenoid valve, a second solenoid valve and a third solenoid valve;
the first solenoid valve, the second solenoid valve and the third solenoid valve are connected in parallel in the pressure regulating circuit.
In some embodiments, the pressure regulation circuit further comprises: a main pump source, a pilot pump source and a pressure sensor;
the main pump source and the pilot pump source are connected in series on a shaft, and the pressure sensor is arranged at an outlet of the main pump source and used for detecting a pressure value at the outlet of the main pump source.
In some embodiments, the high-pressure overflow valve, the low-pressure overflow valve and the proportional throttle valve are respectively arranged in a group at the inlet of the main pump source, and the high-pressure overflow valve, the low-pressure overflow valve and the proportional throttle valve are respectively used for controlling the communication between the high-pressure overflow valve, the low-pressure overflow valve and the outlet of the main pump source.
In some embodiments, when a 15-30MPa high-pressure proportional valve is tested, the second solenoid valve and the third solenoid valve are electrified, the first solenoid valve is powered off, and the high-pressure overflow valve is connected to the outlet of the main pump source to adjust the inlet pressure of a tested valve;
when the 2-15MPa low-pressure proportional valve is tested, the first electromagnetic valve and the third electromagnetic valve are electrified, the second electromagnetic valve is powered off, and the low-pressure overflow valve is connected to the outlet of the main pump source to adjust the inlet pressure of the tested valve;
when a proportional throttle valve with the pressure lower than 2MPa is tested, the first electromagnetic valve and the second electromagnetic valve are electrified, the third electromagnetic valve is powered off, the bypass flow at the outlet of the main pump source is adjusted through the proportional throttle valve, and the pressure at the outlet of the main pump source is constant by utilizing the pressure value detected by the pressure sensor at the outlet of the main pump source in a closed-loop control mode.
In some embodiments, the pressure regulation circuit further comprises: an oil tank; the oil tank is communicated with the main pump source and the pilot pump source, and the main pump source and the pilot pump source are used for sucking oil from the oil tank.
In some embodiments, the high pressure proportional relief valve and/or the low pressure proportional relief valve and/or the proportional throttle valve employ an electro proportional valve.
In some embodiments, the main pump source and the pilot pump source employ variable displacement pumps.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a high-precision pressure regulating circuit, which is used in a hydraulic proportional valve test bench, and comprises: parallelly connected high-pressure proportion overflow valve, low pressure proportion overflow valve and proportion choke valve, pressure regulation return circuit still includes: and the electromagnetic switch valve is used for adjusting the pressure adjusting requirements of different pressure grades through switching of the electromagnetic switch valve. According to the invention, the high-precision pressure regulation requirement of more than 0.5% in the range of 0-30MPa can be realized by connecting the high-pressure proportional overflow valve, the low-pressure proportional overflow valve and the proportional throttle valve in parallel with the pressure regulation loop, so that the test requirements of proportional valves with different pressure grades are met.
In order to make the technical means of the present invention more comprehensible, embodiments consistent with the present invention are described below in detail with reference to the accompanying drawings. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a hydraulic schematic of a high precision pressure regulation circuit of the present invention;
description of the drawings:
1-a main pump source; 2-a pilot pump source;
3-a high-pressure overflow valve; 4-a low-pressure overflow valve;
5-proportional throttle valve; 6-electromagnetic switch valve;
61-a first electromagnetic on-off valve main valve; 62-a second electromagnetic switch valve main valve;
63-a third electromagnetic switch valve main valve; 64-first solenoid valve;
65-a second solenoid valve; 66-a third solenoid valve;
7-an oil tank; 8-pressure sensor.
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.
The minimum regulating pressure of the traditional high-pressure proportional overflow valve regulating mode is high, the pressure regulating precision is low, and the problems of insufficient pressure regulating range and low regulating precision exist in the process of testing the low-pressure proportional valve. The invention provides a high-precision pressure regulating circuit which is used for accurately regulating the inlet pressure of a tested proportional valve and can simultaneously meet the testing requirements of a high-pressure/low-pressure proportional valve.
As shown in fig. 1, which is a hydraulic schematic diagram of a high-precision pressure regulating circuit of the present invention, the pressure regulating circuit includes: the high-pressure proportional overflow valve 3, the low-pressure proportional overflow valve 4, the proportional throttle valve 5 and the electromagnetic switch valve 6 are arranged in the pressure regulating loop in a three-valve parallel mode, and further the high-pressure proportional overflow valve 3 and/or the low-pressure proportional overflow valve 4 and/or the proportional throttle valve 5 are/is an electro-proportional valve. An electromagnetic switch valve 6 is arranged in each pressure regulating loop with three valves connected in parallel, and the pressure regulating requirements of different pressure grades are further realized by controlling the switching of the electromagnetic switch valve 6. The main valves of the electromagnetic opening/closing valve 6 are a first electromagnetic opening/closing valve main valve 61, a second electromagnetic opening/closing valve main valve 62, and a third electromagnetic opening/closing valve main valve 63, and the pilot control valves of the electromagnetic opening/closing valve 6 are a first electromagnetic valve 64, a second electromagnetic valve 65, and a third electromagnetic valve 66; the high-precision pressure regulating device comprises a main valve and a pilot control valve which jointly form an electromagnetic switch valve 6, and can realize the high-precision pressure regulating requirement of more than 0.5 percent within the range of 0-30MPa by connecting a high-pressure proportional overflow valve 3, a low-pressure proportional overflow valve 4 and a proportional throttle valve 5 in parallel with a pressure regulating loop, thereby meeting the testing requirements of proportional valves with different pressure grades.
In some embodiments, the high-pressure proportional overflow valve 3 is switched to regulate pressure in a wide pressure regulation range of 15-30MPa or above, the low-pressure proportional overflow valve 4 is switched to regulate pressure in a medium pressure regulation range of 2-15MPa, and the proportional throttle valve 5 is switched to regulate pressure in a pressure regulation range below 2MPa, so that the outlet pressure is collected in real time by the controller to perform pressure closed-loop control, and the set requirement of the outlet pressure is met.
In some embodiments, the pressure regulation circuit further comprises: a first electromagnetic opening/closing valve main valve 61, a second electromagnetic opening/closing valve main valve 62, a third electromagnetic opening/closing valve main valve 63, a first electromagnetic valve 64, a second electromagnetic valve 65, and a third electromagnetic valve 66, the first electromagnetic opening/closing valve main valve 61, the second electromagnetic opening/closing valve main valve 62, and the third electromagnetic opening/closing valve main valve 63, and the first electromagnetic valve 64, the second electromagnetic valve 65, and the third electromagnetic valve 66 being connected in series in the pressure regulation circuit; the first electromagnetic switching valve main valve 61 and the first electromagnetic valve 64, the second electromagnetic switching valve main valve 62 and the second electromagnetic valve 65, and the third electromagnetic switching valve main valve 63 and the third electromagnetic valve 66 are connected in parallel in the pressure regulating circuit. Further illustratively, the pressure regulation circuit further comprises: the main pump source 1 and the pilot pump source 2 are connected in series on a shaft, preferably, the main pump source 1 and the pilot pump source 2 are variable pumps, and the pressure sensor 8 is arranged at an outlet of the main pump source 1 and is used for detecting a pressure value at the outlet of the main pump source 1. Wherein, the high-pressure overflow valve 3, the low-pressure overflow valve 4 and the proportional throttle valve 5 are respectively arranged in a group at the inlet of the main pump source 1 and respectively control the communication between the high-pressure overflow valve and the outlet of the main pump source 1.
In some embodiments, the principle of operation is: when the 15-30MPa high-pressure proportional valve 3 is tested, the second electromagnetic valve 65 and the third electromagnetic valve 66 are electrified, the first electromagnetic valve 64 is powered off, and only the high-pressure overflow valve 3 is connected to the outlet of the main pump source 1 to adjust the inlet pressure of the tested valve; when the 2-15MPa low-pressure proportional valve 4 is tested, the first electromagnetic valve 64 and the third electromagnetic valve 66 are electrified, the second electromagnetic valve 65 is powered off, and only the low-pressure overflow valve 4 is connected to the outlet of the main pump source 1 to adjust the inlet pressure of the tested valve; when the proportional throttle valve 5 with the pressure below 2MPa is tested, the first electromagnetic valve 64 and the second electromagnetic valve 65 are powered on, the third electromagnetic valve 66 is powered off, the bypass flow at the outlet of the main pump source 1 is adjusted through the proportional throttle valve 5, and the pressure at the outlet of the main pump source 1 is constant in a closed-loop control mode by utilizing the pressure value detected by the pressure sensor 8 at the outlet of the main pump source 1.
In some embodiments, the pressure regulation circuit further comprises: and the oil tank 7 is communicated with the main pump source 1 and the pilot pump source 2, and the main pump source 1 and the pilot pump source 2 suck oil from the oil tank 7. It should be noted that, because the conventional single relief valve has a relatively large minimum set pressure of 2MPa or more and the pressure adjustment accuracy is about 1% of the range, the adjustment accuracy is insufficient in the pressure range of 2-15MPa and the pressure below 2MPa cannot be adjusted. The invention can realize the high-precision pressure regulation requirement of more than 0.5 percent within the range of 0-30MPa by connecting three valves of the high-pressure proportional overflow valve 3, the low-pressure proportional overflow valve 4 and the proportional throttle valve 5 in parallel to the pressure regulation loop, and meet the test requirements of proportional valves with different pressure grades. In addition, the invention is also used for accurately adjusting the inlet pressure of the tested proportional valve and can simultaneously meet the test requirements of the high-pressure/low-pressure proportional valve.
In the description of the present invention, "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, e.g., as being fixed or detachable or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Finally, it should be noted that the above-mentioned embodiments illustrate only preferred embodiments of the invention, and are not intended to limit the invention, so that various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement or the like made within the spirit and principle of the present invention is included in the scope of the claims of the present invention filed as filed.
Claims (9)
1. The utility model provides a high accuracy pressure regulation return circuit for in the hydraulic pressure proportional valve testboard, its characterized in that, the pressure regulation return circuit includes: the high-pressure proportional overflow valve (3), the low-pressure proportional overflow valve (4) and the proportional throttle valve (5) are connected in parallel with the pressure regulating loop; the pressure regulating circuit further comprises: an electromagnetic on-off valve (6); the electromagnetic switch valve (6) is controlled to switch, so that pressure regulation requirements of different pressure grades can be regulated.
2. A high-precision pressure regulating circuit according to claim 1, characterized in that when the pressure is in the range of 15-30MPa, the pressure is switched to the high-pressure proportional relief valve (3) for pressure regulation; when the pressure range is 2-15MPa, switching to the low-pressure proportional overflow valve (4) for pressure regulation; when the pressure range is below 2MPa, switching to the proportional throttle valve (5) for pressure regulation.
3. A high precision pressure regulating circuit according to claim 1 or 2, further comprising: a first solenoid valve (64), a second solenoid valve (65), and a third solenoid valve (66);
the first solenoid valve (64), the second solenoid valve (65) and the third solenoid valve (66) are connected in parallel in the pressure regulating circuit.
4. A high accuracy pressure regulator circuit as defined in claim 3 further comprising: a main pump source (1), a pilot pump source (2) and a pressure sensor (8);
the main pump source (1) and the pilot pump source (2) are connected in series on a shaft, and the pressure sensor (8) is arranged at the outlet of the main pump source (1) and used for detecting the pressure value at the outlet of the main pump source (1).
5. The high-precision pressure regulating circuit according to claim 4, wherein the high-pressure overflow valve (3), the low-pressure overflow valve (4) and the proportional throttle valve (5) are respectively arranged in a group at the inlet of the main pump source (1) and respectively control the communication between the high-pressure overflow valve and the outlet of the main pump source (1).
6. The high-precision pressure regulating circuit according to claim 4 or 5, characterized in that when testing a 15-30MPa high-pressure proportional valve (3), the second solenoid valve (65) and the third solenoid valve (66) are energized, the first solenoid valve (64) is de-energized, and the high-pressure overflow valve (3) is connected to the outlet of the main pump source (1) to regulate the inlet pressure of the tested valve;
when the 2-15MPa low-pressure proportional valve (4) is tested, the first electromagnetic valve (64) and the third electromagnetic valve (66) are electrified, the second electromagnetic valve (65) is powered off, and the low-pressure overflow valve (4) is connected to the outlet of the main pump source (1) to adjust the inlet pressure of a tested valve;
when a proportional throttle valve (5) below 2MPa is tested, the first electromagnetic valve (64) and the second electromagnetic valve (65) are electrified, the third electromagnetic valve (66) is powered off, the bypass flow at the outlet of the main pump source (1) is adjusted through the proportional throttle valve (5), and the pressure at the outlet of the main pump source (1) is constant by utilizing the pressure value detected by the pressure sensor (8) at the outlet of the main pump source (1) in a closed-loop control mode.
7. The high accuracy pressure regulator circuit of claim 6, further comprising: an oil tank (7); the oil tank (7) is communicated with the main pump source (1) and the pilot pump source (2), and the main pump source (1) and the pilot pump source (2) are used for sucking oil from the oil tank (7).
8. A high precision pressure regulating circuit according to claim 7, characterized in that the high pressure proportional relief valve (3) and/or the low pressure proportional relief valve (4) and/or the proportional throttle valve (5) employs an electro proportional valve.
9. A high accuracy pressure regulating circuit according to claim 7 or 8, characterized in that the main pump source (1) and the pilot pump source (2) employ variable displacement pumps.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210146291.XA CN114542549A (en) | 2022-02-17 | 2022-02-17 | High-precision pressure regulating loop |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210146291.XA CN114542549A (en) | 2022-02-17 | 2022-02-17 | High-precision pressure regulating loop |
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| CN114542549A true CN114542549A (en) | 2022-05-27 |
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| CN202210146291.XA Pending CN114542549A (en) | 2022-02-17 | 2022-02-17 | High-precision pressure regulating loop |
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| JPH11183348A (en) * | 1997-12-24 | 1999-07-09 | Japan Tobacco Inc | Material testing machine |
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| CN101871478A (en) * | 2010-07-07 | 2010-10-27 | 金碧华 | Loading device of hydraulic motor test board |
| CN201753720U (en) * | 2010-07-23 | 2011-03-02 | 浙江苏强格液压有限公司 | Loading device of hydraulic system |
| CN202164653U (en) * | 2011-04-02 | 2012-03-14 | 徐州徐工挖掘机械有限公司 | Hydraulic system of excavator with automatically controlled maximum pressure |
| CN102562563A (en) * | 2012-01-11 | 2012-07-11 | 福州大学 | Energy-saving stepless pressure regulating type hydraulic system for high-pressure pump performance test bench |
| CN203730436U (en) * | 2014-02-27 | 2014-07-23 | 北京南车时代机车车辆机械有限公司 | Anchor drilling rig and pilot oil source valve bank thereof |
| CN207598611U (en) * | 2017-11-27 | 2018-07-10 | 江苏恒立液压科技有限公司 | Multi-stage pressure regulating circuit |
| CN212155113U (en) * | 2020-01-09 | 2020-12-15 | 上海辛金路流体技术有限公司 | Hydraulic pump performance test bench |
-
2022
- 2022-02-17 CN CN202210146291.XA patent/CN114542549A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1053110A (en) * | 1989-12-31 | 1991-07-17 | 太原工业大学 | Combined decompressing and speed-regulating valve by hydroelectric proportion |
| JPH0899552A (en) * | 1994-09-30 | 1996-04-16 | Nissan Motor Co Ltd | Four wheel drive |
| JPH1113088A (en) * | 1997-06-24 | 1999-01-19 | Kubota Corp | Hydraulic control device for operation of rotary work machine |
| JPH11183348A (en) * | 1997-12-24 | 1999-07-09 | Japan Tobacco Inc | Material testing machine |
| CN101178062A (en) * | 2007-10-26 | 2008-05-14 | 中国人民解放军空军工程大学 | Variable hydraulic pump pressure flow characteristics auto-testing method |
| CN101871478A (en) * | 2010-07-07 | 2010-10-27 | 金碧华 | Loading device of hydraulic motor test board |
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| CN102562563A (en) * | 2012-01-11 | 2012-07-11 | 福州大学 | Energy-saving stepless pressure regulating type hydraulic system for high-pressure pump performance test bench |
| CN203730436U (en) * | 2014-02-27 | 2014-07-23 | 北京南车时代机车车辆机械有限公司 | Anchor drilling rig and pilot oil source valve bank thereof |
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| CN212155113U (en) * | 2020-01-09 | 2020-12-15 | 上海辛金路流体技术有限公司 | Hydraulic pump performance test bench |
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