CN110345132B - Double-input characteristic test system for servo valve - Google Patents
Double-input characteristic test system for servo valve Download PDFInfo
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- CN110345132B CN110345132B CN201910645872.6A CN201910645872A CN110345132B CN 110345132 B CN110345132 B CN 110345132B CN 201910645872 A CN201910645872 A CN 201910645872A CN 110345132 B CN110345132 B CN 110345132B
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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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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/003—Machine valves
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- General Engineering & Computer Science (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
A dual-input characteristic test system for a servo valve comprises a measurement and control system and a test bed, wherein a tested servo valve is arranged on the working table surface of the test bed, an actuator is arranged on the test bed, and the tested servo valve drives the actuator to generate displacement proportional to a loading signal under the action of the loading signal and feeds the displacement back to the mechanical feedback displacement input end of the tested servo valve; the measurement and control system comprises a lower computer digital logic circuit and an upper computer human-computer interaction interface, a user inputs a loading signal through the upper computer human-computer interaction interface, the lower computer digital logic circuit converts the loading signal into a constant current source, applies the constant current source to the electrical input end of the servo valve to be measured, collects the displacement of the mechanical feedback displacement input end of the servo valve to be measured, and feeds the displacement back to the upper computer human-computer interaction interface for display, so that the user can judge whether the dual-input characteristic of the servo valve meets the requirement. The method can realize the function of independently testing the double-input characteristics of the servo valve, and achieve the purpose of judging the performance of the double-input characteristics.
Description
Technical Field
The invention relates to a dual-input characteristic testing system for a servo valve, and belongs to the technical field of hydraulic control.
Background
The electro-hydraulic servo valve is applied to a hydraulic control system and is a core control element for carrying out closed-loop control on position, pressure or speed of the system. The electromechanical dual-input servo valve is a type of electro-hydraulic servo valve, is commonly used in aerospace and aviation position vector servo control systems, and has dual-input characteristics of: the performance indexes of the servo system are directly influenced by characteristic indexes such as double-input hysteresis, double-input gain, double-input displacement, double-input symmetry and the like. The dual-input characteristic indexes cannot be independently tested in a common servo valve performance debugging test system, and the servo valve and the servo system are required to be tested in a joint test, so that the performance of the indexes cannot be predicted.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the dual-input characteristic testing system for the servo valve overcomes the defects of the prior art, realizes the function of testing the dual-input characteristic of the servo valve independently, and achieves the purpose of judging the performance of the dual-input characteristic.
The technical solution of the invention is as follows:
a double-input characteristic test system for a servo valve comprises a measurement and control system and a test bed;
the servo valve to be tested is arranged on the working table surface of the test bed, the actuator is arranged on the test bed, and the servo valve to be tested drives the actuator to generate displacement proportional to the loading signal under the action of the loading signal and feeds the displacement back to the mechanical feedback displacement input end of the servo valve to be tested;
the measurement and control system comprises a lower computer digital logic circuit and an upper computer human-computer interaction interface, a user inputs a loading signal through the upper computer human-computer interaction interface, the lower computer digital logic circuit converts the loading signal into a constant current source, applies the constant current source to the electrical input end of the servo valve to be measured, collects the displacement of the mechanical feedback displacement input end of the servo valve to be measured, and feeds the displacement back to the upper computer human-computer interaction interface for display, so that the user can judge whether the dual-input characteristic of the servo valve meets the requirement.
The test bed comprises an actuator, a feedback push rod, an axial displacement sensor and a double-input displacement sensor;
the tested servo valve is arranged on the working table surface of the test bed, the mechanical feedback displacement input end of the tested servo valve is vertically connected with the piston rod of the actuator through the feedback push rod, the axial displacement sensor is connected with the piston rod of the actuator through the sensor connecting rod, and the axial displacement sensor is parallel to the piston rod of the actuator; the dual-input displacement sensor is vertically connected to the piston rod of the actuator, and the lower computer digital logic circuit is used for acquiring the displacement of the dual-input displacement sensor; the load chamber of the servo valve to be tested is connected with two control chambers of the actuator.
The actuator comprises an actuator piston rod, an actuator left end cover, an actuator sleeve and an actuator right end cover;
actuator left end housing and actuator right-hand member end cover are installed respectively in the actuator sleeve left and right sides, and the actuator piston rod passes actuator left end housing and actuator right-hand member end cover to can carry out the side-to-side motion along the actuator piston rod sleeve, actuator piston rod sleeve and the integrative design of actuator left end cover.
The feedback push rod comprises a first push rod, a second push rod, a guide key and a bearing;
one end of the first push rod is connected with the inside of the head end of the second push rod in a threaded manner, and the other end of the first push rod is connected with the mechanical feedback displacement input end of the servo valve to be tested; the end of the second push rod is connected with the actuator piston rod through a bearing, a key groove is formed in the side wall of the second push rod, a guide key is arranged in the key groove, and the guide key is fixed on the inner wall of the sleeve of the actuator piston rod.
Through rotatory first push rod, adjust the initial position of actuator piston rod and be located middle zero position, prevent the motion in-process, actuator piston rod and actuator cylinder body collision.
The piston rod of the actuator is a conical rod.
The taper of the piston rod of the actuator is equal to the stroke of the piston rod of the actuator/the feedback stroke of the double input ends of the servo valve to be measured.
The test bed also comprises an installation transition block, the installation transition block is provided with an oil way, and a load cavity of the servo valve to be tested is connected with two control cavities of the actuator through the oil way on the installation transition block;
the tested servo valve and the actuator are arranged on the mounting transition block, and the mounting transition block is arranged on the working table surface of the test bed.
The double-input displacement sensor is connected with a sleeve of the piston rod of the actuator through a sensor sleeve.
The test procedure was as follows:
step 1: installing a tested servo valve on a test bed, and assembling a dual-input characteristic test system for the servo valve;
step 2: a user inputs a loading signal through a human-computer interaction interface of the upper computer;
and step 3: the servo valve outputs flow proportional to the loading signal, the piston rod of the actuator displaces, and the displacement is fed back to the mechanical feedback displacement input end of the servo valve to be tested through the feedback push rod;
and 4, step 4: the displacement of the mechanical feedback displacement input end is input to the lower computer digital logic circuit through the double-input displacement sensor, the lower computer digital logic circuit outputs the displacement to the upper computer human-computer interaction interface, and the upper computer human-computer interaction interface generates a test curve and a double-input characteristic index value according to the displacement and displays the test curve and the double-input characteristic index value so that a user can judge whether the double-input characteristic of the servo valve meets the requirement.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention designs the piston rod of the actuator with a taper structure, and realizes the conversion of the axial movement displacement of the actuator into the displacement input of the mechanical input end of the servo valve in the direction vertical to the axial movement displacement of the actuator through the reasonable taper angle design.
(2) The invention designs the feedback push rod with the key groove and the bearing structure, and the feedback push rod acts on the piston rod of the actuator through the bearing roller, so that the purposes of reducing friction force and avoiding rolling when the displacement is input into the servo valve are realized.
(3) The invention designs a vertical and horizontal double-displacement sensor structure mode, which not only can realize the displacement acquisition function of the mechanical input end of the servo valve, but also can realize the automatic position correction function of the piston rod of the actuator in the cylinder by utilizing an electric position closed-loop system under the condition of non-mechanical displacement input.
(4) According to the invention, the recovery spring is designed on the tested servo valve, and when the feedback push rod and the servo valve ejector rod are abraded due to friction, the function of self-compensation of the abraded part can be realized through the recovery spring.
(5) According to the invention, through the displacement curve, the test of indexes such as rated control displacement, dual-input gain, dual-input linearity, dual-input symmetry, dual-input hysteresis and the like of the dual-input characteristic servo valve can be realized, and the test of all dual-input characteristic projects is covered.
(6) The double-input displacement test curve can be drawn in real time during testing, and the automatic calculation and real-time display functions of various indexes after the drawing of the test curve is finished are realized.
Drawings
FIG. 1 is an external view of a dual input characteristic testing system for a servo valve;
FIG. 2 is a front view of a dual input characteristic testing system for a servo valve;
FIG. 3 is a top view of a dual input characteristic testing system for a servo valve;
FIG. 4 is a schematic perspective view of a dual input characteristic testing system for a servo valve;
FIG. 5 is a schematic view of a tapered piston rod;
FIG. 6 is a key slot and bearing arrangement feedback push rod;
FIG. 7 is a diagram of a human-computer interface of a host computer.
Detailed Description
As shown in fig. 1, the present invention provides a dual input characteristic testing system for a servo valve, which includes a measurement and control system and a test bed. The servo valve to be tested is arranged on the working table surface of the test bed, the actuator is arranged on the test bed, and the servo valve to be tested drives the actuator to generate displacement proportional to the loading signal under the action of the loading signal and feeds the displacement back to the mechanical feedback displacement input end of the servo valve to be tested 8.
The measurement and control system comprises a lower computer digital logic circuit and an upper computer human-computer interaction interface, a user inputs a loading signal through the upper computer human-computer interaction interface, the lower computer digital logic circuit carries out digital-to-analog conversion and amplification processing on the loading signal to obtain a constant current source, the constant current source is applied to an electrical input end of the servo valve to be measured, the displacement of a mechanical feedback displacement input end of the servo valve 8 to be measured is collected and fed back to the upper computer human-computer interaction interface to be displayed, and the user can judge whether the dual-input characteristic of the servo valve meets the requirement or not.
Specifically, as shown in fig. 2, the test bed comprises an actuator, a feedback push rod 9, an axial displacement sensor 11, a dual-input displacement sensor 1 and a transition mounting block, the servo valve to be tested is mounted on the working table of the test bed, the mechanical feedback displacement input end of the servo valve is vertically connected with the piston rod 3 of the actuator through the feedback push rod 9, the axial displacement sensor 11 is connected with the piston rod 3 of the actuator through a sensor connecting rod 10, and the axial displacement sensor 11 is parallel to the piston rod 3 of the actuator; the dual-input displacement sensor 1 is vertically connected to the piston rod 3 of the actuator, and the lower computer digital logic circuit is used for collecting the displacement of the dual-input displacement sensor; the load chamber of the servo valve to be tested is connected with two control chambers of the actuator. The excessive block 7 is installed to be provided with an oil path, and a load cavity of the servo valve 8 to be tested is connected with two control cavities of the actuator through the oil path on the excessive block 7. The tested servo valve 8 and the actuator are arranged on the excessive installation block 7, and the excessive installation block 7 is arranged on the working platform of the test bed.
The actuator comprises an actuator piston rod 3, an actuator left end cover 4, an actuator sleeve 5 and an actuator right end cover 6. Install respectively in the 5 left and right sides of actuator sleeve in actuator left end housing 4 and actuator right-hand member lid 6, actuator piston rod 3 passes actuator left end housing 4 and actuator right-hand member lid 6 to can carry out the side-to-side motion along 3 sleeves of actuator piston rod, 3 sleeves of actuator piston rod and 4 integrative designs of actuator left end housing. Fig. 3 is a plan view. Fig. 4 is a schematic perspective view of a dual input characteristic testing system for a servo valve.
As shown in fig. 6, the feedback rod 9 includes a first rod 91, a second rod 92, a guide key 17, and a bearing 18. One end of the first push rod 91 is connected to the inside of the head end of the second push rod 92 in a threaded manner, and the other end of the first push rod is connected with the mechanical feedback displacement input end of the servo valve 8 to be tested; the end of the second push rod 92 is connected with the actuator piston rod 3 through a bearing 18, a key groove is formed in the side wall of the second push rod 92, a guide key 17 is arranged in the key groove, and the guide key 17 is fixed on the inner wall of the sleeve of the actuator piston rod 3. Through rotatory first push rod 91, adjust the initial position of actuator piston rod 3 and be located middle zero position, prevent the motion in-process, actuator piston rod 3 and actuator cylinder body collision.
As shown in fig. 5, the actuator piston rod 3 is a tapered rod. The taper is the stroke of the piston rod 3 of the actuator/the double-input-end feedback stroke of the servo valve 8 to be measured. Fig. 5 is an enlarged view of I in fig. 2.
As shown in fig. 2, the dual input displacement sensor 1 is connected to the sleeve of the actuator piston rod 3 via a sensor sleeve 2.
FIG. 7 is a diagram of a human-computer interface of a host computer.
The digital logic circuit of the lower computer is provided with an amplifying circuit, the current frequency adjusting range can reach 0.01-10 Hz, and the input function of a triangular wave or sine wave constant current source can be realized.
The spring is installed to the relative one side of 8 mechanical feedback displacement input ends of servo valve under test, when wearing and tearing take place because of the friction between feedback push rod and the servo valve ejector pin under test, can realize wearing and tearing position self-compensation function through resumeing the spring.
The test process of the invention is as follows:
step 1: installing a tested servo valve on a test bed, and assembling a dual-input characteristic test system for the servo valve;
step 2: a user inputs a loading signal through a human-computer interaction interface of the upper computer;
and step 3: the servo valve outputs flow proportional to the loading signal, the piston rod 3 of the actuator is displaced, and the displacement is fed back to the mechanical feedback displacement input end of the servo valve to be tested through the feedback push rod 9;
and 4, step 4: the displacement of the mechanical feedback displacement input end is input to a lower computer digital logic circuit through the double-input displacement sensor 1, the lower computer digital logic circuit outputs the displacement to an upper computer human-computer interaction interface, and the upper computer human-computer interaction interface generates a test curve and a double-input characteristic index value according to the displacement and displays the test curve and the double-input characteristic index value so that a user can judge whether the double-input characteristic of the servo valve meets the requirement.
The invention can be designed into multiple stations, each station is designed according to the test bed scheme, and the double-input characteristic test of the double-input servo valve with three specifications of large, medium and small in the flow range of 20-200L/min is realized through the size design of the actuator sleeve.
The invention has the function of self-checking of system startup, and can realize the abnormal self-checking of various functions of pressure, temperature and the like before the system is started up.
Those skilled in the art will appreciate that the invention may be practiced without these specific details.
Claims (6)
1. A dual-input characteristic test system for a servo valve is characterized in that: comprises a measurement and control system and a test bed;
the servo valve to be tested is arranged on the working table surface of the test bed, the actuator is arranged on the test bed, and the servo valve to be tested drives the actuator to generate displacement proportional to the loading signal under the action of the loading signal and feeds the displacement back to the mechanical feedback displacement input end of the servo valve to be tested;
the measurement and control system comprises a lower computer digital logic circuit and an upper computer human-computer interaction interface, a user inputs a loading signal through the upper computer human-computer interaction interface, the lower computer digital logic circuit converts the loading signal into a constant current source, applies the constant current source to the electrical input end of the servo valve to be measured, collects the displacement of the mechanical feedback displacement input end of the servo valve to be measured, and feeds the displacement back to the upper computer human-computer interaction interface for display, so that the user can judge whether the dual-input characteristic of the servo valve meets the requirement;
the test bed comprises an actuator, a feedback push rod (9), an axial displacement sensor (11) and a double-input displacement sensor (1);
the servo valve to be tested is arranged on the working table surface of the test bed, the mechanical feedback displacement input end of the servo valve to be tested is vertically connected with the actuator piston rod (3) through a feedback push rod (9), the axial displacement sensor (11) is connected with the actuator piston rod (3) through a sensor connecting rod (10), and the axial displacement sensor (11) is parallel to the actuator piston rod (3); the dual-input displacement sensor (1) is vertically connected to the piston rod (3) of the actuator, and the lower computer digital logic circuit is used for acquiring the displacement of the dual-input displacement sensor; the load cavity of the tested servo valve is connected with two control cavities of the actuator;
the actuator comprises an actuator piston rod (3), an actuator left end cover (4), an actuator sleeve (5) and an actuator right end cover (6);
the left end cover (4) and the right end cover (6) of the actuator are respectively arranged at the left side and the right side of the actuator sleeve (5), the piston rod (3) of the actuator penetrates through the left end cover (4) and the right end cover (6) of the actuator and can move left and right along the sleeve of the piston rod (3) of the actuator, and the sleeve of the piston rod (3) of the actuator and the left end cover (4) of the actuator are integrally designed;
the feedback push rod (9) comprises a first push rod (91), a second push rod (92), a guide key (17) and a bearing (18);
one end of the first push rod (91) is connected to the interior of the head end of the second push rod (92) in a threaded manner, and the other end of the first push rod is connected with the mechanical feedback displacement input end of the servo valve (8) to be tested; the tail end of the second push rod (92) is connected with the actuator piston rod (3) through a bearing (18), a key groove is formed in the side wall of the second push rod (92), a guide key (17) is arranged in the key groove, and the guide key (17) is fixed on the inner wall of a sleeve of the actuator piston rod (3);
through rotatory first push rod (91), the initial position of adjusting actuator piston rod (3) is located middle zero position, prevents the motion in-process, and actuator piston rod (3) and actuator cylinder body collide.
2. The dual input characteristic testing system for a servo valve according to claim 1, wherein: the piston rod (3) of the actuator is a conical rod.
3. The dual input characteristic testing system for a servo valve according to claim 2, wherein: the conicity of the actuator piston rod (3) is = the stroke of the actuator piston rod (3)/the double-input-end feedback stroke of the servo valve (8) to be tested.
4. The dual input characteristic testing system for a servo valve according to claim 1, wherein: the test bed also comprises an installation transition block (7), the installation transition block (7) is provided with an oil way, and a load cavity of the servo valve (8) to be tested is connected with two control cavities of the actuator through the oil way on the installation transition block (7);
the tested servo valve (8) and the actuator are arranged on the excessive installation block (7), and the excessive installation block (7) is arranged on the working platform surface of the test bed.
5. The dual input characteristic testing system for a servo valve according to claim 1, wherein: the double-input displacement sensor (1) is connected with a sleeve of the actuator piston rod (3) through the sensor sleeve (2).
6. The dual input characteristic testing system for a servo valve according to claim 1, wherein: the test procedure was as follows:
step 1: installing a tested servo valve on a test bed, and assembling a dual-input characteristic test system for the servo valve;
step 2: a user inputs a loading signal through a human-computer interaction interface of the upper computer;
and step 3: the servo valve outputs flow proportional to the loading signal, the piston rod (3) of the actuator displaces, and the displacement is fed back to the mechanical feedback displacement input end of the servo valve to be tested through the feedback push rod (9);
and 4, step 4: the displacement of the mechanical feedback displacement input end is input to a lower computer digital logic circuit through a double-input displacement sensor (1), the lower computer digital logic circuit outputs the displacement to an upper computer human-computer interaction interface, and the upper computer human-computer interaction interface generates a test curve and a double-input characteristic index value according to the displacement and displays the test curve and the double-input characteristic index value so that a user can judge whether the double-input characteristic of the servo valve meets the requirement.
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| CN201910645872.6A CN110345132B (en) | 2019-07-17 | 2019-07-17 | Double-input characteristic test system for servo valve |
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| CN201910645872.6A CN110345132B (en) | 2019-07-17 | 2019-07-17 | Double-input characteristic test system for servo valve |
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| CN110345132B true CN110345132B (en) | 2021-07-09 |
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| CN114112347B (en) * | 2021-11-18 | 2024-04-09 | 庆安集团有限公司 | Small-size modular constant force loading life test device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN206449056U (en) * | 2016-08-30 | 2017-08-29 | 北京交通大学 | Dual input servo valve dual input characteristic test frock and test system |
| CN207526811U (en) * | 2017-10-27 | 2018-06-22 | 北京精密机电控制设备研究所 | A kind of nozzle-flapper servo valve prestage discharge coefficient test device |
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| CN2427664Y (en) * | 2000-07-07 | 2001-04-25 | 周泰经 | Microcomputerized speed regulator directed linkage type hydraulic arrangement |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN206449056U (en) * | 2016-08-30 | 2017-08-29 | 北京交通大学 | Dual input servo valve dual input characteristic test frock and test system |
| CN207526811U (en) * | 2017-10-27 | 2018-06-22 | 北京精密机电控制设备研究所 | A kind of nozzle-flapper servo valve prestage discharge coefficient test device |
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