CN101329214A - Dynamic measuring apparatus of shaft core mobile approximate hydraulic valve core wall surface flow field pressure - Google Patents
Dynamic measuring apparatus of shaft core mobile approximate hydraulic valve core wall surface flow field pressure Download PDFInfo
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- CN101329214A CN101329214A CNA200810063193XA CN200810063193A CN101329214A CN 101329214 A CN101329214 A CN 101329214A CN A200810063193X A CNA200810063193X A CN A200810063193XA CN 200810063193 A CN200810063193 A CN 200810063193A CN 101329214 A CN101329214 A CN 101329214A
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Abstract
The invention discloses a dynamic measuring device of the flow field pressure of the wall surface of a semi-hydraulic valve plug with a movable shaft core. The inner side of the valve plug is processed into a through hole, and the normal direction of the wall surface of the valve plug is provided with pressure measuring pores that are distributeed along the axial and the circumferential directions. The inner side of the shaft core that is arranged in the through hole of the valve plug is processed into a deep hole, the normal direction of a wall surface of the shaft core is opened with over two pressure sensor orifices that distribute along the axial direction, and high-frequency pressure sensors are arranged inside the orifices. By moving and rotating the shaft core inside the through hole of the valve plug, the over two pressure sensors are simultaneously communicated with different pressure measuring pores of the valve plug, and the dynamic measurement of flow field pressure of an outer wall surface of the valve plug is realized, thus realizing the researches on flow field pressure distribution of gas cavity, wake flow desquamation property of gas cavity and noise of gas cavity, etc. The valve plug of the invention can take throttling valve structures with full circumferential openings or parts of circumferential openings, etc., and can be widely applied into real hydraulic valves. The dynamic measuring device of flow field pressure of the wall surface of the semi-hydraulic valve plug with the movable shaft core is an experimental platform, and can efficiently implement the researches on the control of working noise and vibration of slide valves and structure optimization of flow passages.
Description
Technical field
The present invention relates to hydraulic valve interior flow field device for pressure measurement, especially relate to the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of a kind of core.
Background technology
The hydraulic efficiency slide valve structure is a kind of basic structure form of hydraulic valve, and complete all openings, non-complete all openings are arranged, and can constitute reversal valve, directional throttle valve, throttling valve, flowrate control valve etc. on the function of valve, and the operation control mode has manually, ratio, servo etc.Because guiding valve flow passage structure complexity, size is less, and flow velocity is very fast, forms complicated fluid field pressure and distributes, and finally often causes the generation of this harmful phenomenon of air pocket.The existence of air pocket not only causes certain fluid field pressure loss, also often causes the vibration of Hydraulic Elements and a large amount of noises.The research of stream field pressure distribution and air pocket mechanism is the difficult point of studying both at home and abroad always.Nascent and the development of air pocket in the guiding valve is crumbled and fall and the runner pressure inside distributes closely relatedly, and the magnitude of Cavitation Noise is not only relevant with the air pocket development degree, also with the shedding frequence of the wake flow of crumbling and fall, crumbles and fall and distinguishes pressure important relation is arranged.Therefore, distribution of runner internal pressure and pressure change the variation tendency that frequency domain characteristic has been represented Cavitation Noise in a sense.Change along with structural parameters and flow parameter, runner internal pressure characteristic changes, the air pocket position, form and severe degree change, and then cause the variation of Cavitation Noise and vibration of element characteristic, distribution and frequency domain characteristic by the research fluid field pressure can be the optimal design of flow passage structure, and effective control of Cavitation Noise vibration provides good foundation.
According at present to the cavitation in the hydraulic valve discover that air pocket extends downstream with liquid flow after producing, and the position deviation of spool wall takes place to point to.Crumble and fall after the air pocket wake flow comes off is the immediate cause that causes Cavitation Noise.The come off pressure surge that causes of pressure distribution in zone of crumbling and fall and air pocket wake flow has very significant effects to the magnitude level of the noise of crumbling and fall.Therefore, the air pocket zone of crumbling and fall, promptly pressure distribution, the wave characteristic of nearly spool wall have important Research Significance.Have the research of miscarriage pressure distribution in some hydraulic valves at present, but research object is the pressure distribution of nearly valve body wall.According to its result of study that crumbles and fall that distributes of air pocket in the above-mentioned hydraulic valve, cause the wake flow of Cavitation Noise to come off to crumble and fall nearly spool wall place takes place, so the pressure investigation of nearly spool wall is had even more important meaning.Consider the liquid flow model of non-ideality simultaneously, the pressure measurements of nearly valve body wall and the pressure distribution in actual flow field are existence than big-difference.
Use pressure sensingly more than two, can gather the pressure signal of zones of different simultaneously, realize the kinetic measurement that fluid field pressure in a big way distributes, and then judge the trend that air pocket distributes; High-frequency pressure sensor axially is equally spaced, and can effectively catch the frequency domain characteristic that the air pocket wake flow comes off and crumbles and fall.
Summary of the invention
The object of the present invention is to provide the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of a kind of core.
In order to achieve the above object, the technical solution used in the present invention is:
Valve body is fixed on the valve seat, spool is packed in the valve body, the axle core cooperates with valve core through hole, the axle core can rotate in valve core through hole and axially relative displacement, the both sides of valve seat are the installing and locating plate respectively, dog screw on two location-plates withstands on the both ends of the surface of spool respectively, the location gauge block is installed between the axle core and spool end of a side, adjusting location gauge block is determined the axial location between spool and the axle core, spool wall normal direction has throttling channel bottom surface pressure measurement aperture and oil back chamber pressure measurement aperture, distributes vertically more than 3 groups; Axle core wall normal direction has the pressure transducer hole, distributes vertically more than two; High-frequency pressure sensor is equipped with in inside, pressure transducer hole, and the signal line passes axle core deep hole and the extraneous data acquisition system (DAS) in pressure transducer hole are joined.
Described oil back chamber pressure measurement aperture distributes more than six along central angles such as circumference, and is equally spaced vertically more than three groups; Pressure measurement aperture in throttling channel bottom surface is symmetrically distributed in both sides, throttling channel bottom surface, and axial spacing equates that pressure measurement little centerline hole in throttling channel bottom surface intersects with the axle wire mandrel; Axial line distance all equates between adjacent segments chute pressure measurement aperture axial distance, adjacent oil back chamber pressure measurement aperture axial distance and adjacent segments chute pressure measurement aperture and the oil back chamber pressure measurement aperture, is 2.0～3.0mm, hole diameter 0.1～0.5mm.
Described pressure transducer hole is offered along axle core wall normal direction, distributes vertically more than two; The pressure transducer pitch of holes equates that with throttling channel pressure measurement aperture axial spacing the pressure transducer pitch of holes equates with oil back chamber pressure measurement aperture axial spacing; Pressure transducer bore dia 0.5～1.0mm is greater than the diameter of throttling channel pressure measurement aperture and oil back chamber pressure measurement aperture.
Described location gauge block thickness equates with throttling channel pressure measurement aperture axial spacing that all location gauge block thickness equate with oil back chamber pressure measurement aperture axial spacing; During initial alignment, when promptly not having the location gauge block, pressure measurement aperture in top is identical with pressure transducer hole, top axial location.
The highest response frequency 100kHz of described high-frequency pressure sensor satisfies the frequency requirement of Cavitation Noise research; Two high-frequency pressure sensor are used simultaneously, satisfy the requirement on experimental period and the space.
The beneficial effect that the present invention has is:
This measurement mechanism is realized the throttle opening adjusting by dog screw, by changing the relative spool rotation of location gauge block quantity and axle core realization axle core pressure transducer hole, the i.e. aligning of the different pressure measurement apertures with spool of high-frequency pressure sensor.Use two above high-frequency pressure sensor simultaneously along an axle wire mandrel direction, realize air pocket wake flow the crumble and fall pressure distribution in zone and the real time dynamic measurement of pressure surge.The present invention measures accurately, and is easy to operate, and especially research has realistic meanings at the air pocket in the hydraulic efficiency slide valve.
Description of drawings
Fig. 1 is a general structure synoptic diagram of the present invention.
Fig. 2 is the A-A pressure measurement aperture distribution plan of Fig. 1.
Fig. 3 is that the B-B oil back chamber wall pressure of Fig. 2 is measured schematic cross-section.
Fig. 4 is that the C-C throttling channel base pressure of Fig. 2 is measured schematic cross-section.
Fig. 5 is that the D-D oil back chamber wall pressure of Fig. 2 is measured schematic cross-section.
Fig. 6 is that the D-D throttling channel base pressure of Fig. 2 is measured schematic cross-section.
Among the figure: 1. valve body, 2. spool, 3. a core, 4. valve seat, 5. location-plate, 6. setscrew nut, 7. hold-down nut, 8. oil-in, 9. oil-out, 10. throttling channel, 11. throttling channel bottom surface pressure measurement apertures, 12. pressure transducer holes, 13. high-frequency pressure sensor, 14. the valve body boss, 15. core deep holes, 16. location gauge blocks, 17. oil back chamber, 18. axle core, poppet shaft be to position change, 19. valve core through hole, 20. oil back chamber pressure measurement apertures, 21. signal wire, 22. the relative spool rotation of axle core, 23. throttling limits, 24. signals collecting and disposal system.
Embodiment
The present invention is further illustrated below in conjunction with drawings and Examples.
The purpose of this invention is to provide the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of a kind of core.By changing the change that location gauge block working quantity realizes axle core and spool axial location, promptly realize the aligning of pressure transducer hole and axial different pressure measurement apertures, relative valve core through hole turning axle core, the aligning of realization pressure transducer hole and circumferential different pressure measurement apertures; Spool changes valve body over to after working good with the axle core, by the axial location of setscrew nut realization with valve body, the i.e. adjustment of throttle opening; Pressure measurement aperture axial spacing, pressure transducer hole axial spacing and location gauge block thickness equates, aims at the location between convenient realization pressure transducer hole and the pressure measurement aperture; The pressure transducer bore dia is greater than the pressure measurement hole diameter; (10～100kHz) use two above high-frequency pressure sensor simultaneously, obtain the real-time distribution situation of pressure, high-frequency pressure sensor axially is equally spaced, and can effectively obtain the crumble and fall pressure surge characteristic in zone of air pocket, and then catches the time-frequency domain characteristic that the air pocket wake flow comes off, crumbles and fall.
As Fig. 1～shown in Figure 6, the present invention is fixed on valve body 1 on the valve seat 4 by four trip bolts; Axle core 3 closely cooperates with valve core through hole 19, guarantees that simultaneously a core 3 can rotate freely in valve core through hole 19 and axially relative displacement, determines that by location gauge block 16 axial location between spool 2 and the axle core 3 concerns; Spool 2 cooperates with axle core 3 and locatees in the valve body 1 of packing into later, and the axial location relation between spool 2 and the valve body 1 is regulated by the rotation of dog screw 6 and realized, promptly realizes the adjustment of throttle opening; Dog screw 6 is installed on the location-plate 5, and location-plate 5 other ends are fixed on the valve body 1 by gib screw 7; Spool 2 wall normal direction have throttling channel pressure measurement bottom surface pressure measurement aperture 11 and oil back chamber pressure measurement aperture 20, distribute vertically and circumferentially; Axle core 3 wall normal direction have pressure transducer hole 12, distribute vertically more than two; High-frequency pressure sensor 13 is equipped with in 12 inside, pressure transducer hole, and signal wire 21 links to each other with pressure transducer 13, is collected in disposal system 24 through axle in-core hole 15 with outer signals and joins.Oil back chamber pressure measurement aperture 20 distributes more than six along central angles such as circumference, and is equally spaced vertically more than three groups; Throttling channel bottom surface pressure measurement aperture 11 is symmetrically distributed in both sides, throttling channel 10 bottom surface, axial spacing equates, throttling channel bottom surface pressure measurement aperture 11 center lines and axle core 2 axes intersect, for full Zhou Kaiyou throttling channel 10 structures, pressure measurement aperture 11 in throttling channel bottom surface distributes more than 6 along central angles such as circumference.Axial line distance all equates between adjacent segments chute pressure measurement aperture 11 axial distances, adjacent oil back chamber pressure measurement aperture 20 axial distances and adjacent segments chute pressure measurement aperture 11 and the oil back chamber pressure measurement aperture 20, is 2.0～3.0mm, hole diameter 0.1～0.5mm.Pressure transducer hole 12 is offered along axle core 3 wall normal direction, distributes vertically more than two; Pressure transducer hole 12 spacings equate with throttling channel bottom surface pressure measurement aperture 11 axial spacings; Pressure transducer hole 12 diameters, 0.5～1.0mm is greater than the diameter of throttling channel bottom surface pressure measurement aperture 11 and oil back chamber pressure measurement aperture 20.All location gauge block 16 thickness equate with throttling channel bottom surface pressure measurement aperture 11 axial spacings; During initial alignment, when promptly not having location gauge block 16, throttling channel bottom surface pressure measurement aperture 11 is identical with pressure transducer hole, top 12 axial locations near the throttling limit 23.High-frequency pressure sensor 13 the highest response frequency 100kHz satisfy the frequency requirement of Cavitation Noise research; Two high-frequency pressure sensor 13 are used simultaneously, satisfy the requirement on experimental period and the space.
The portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device operating process of above-mentioned axle core is as follows:
As shown in Figure 1, axle core 3 is installed in the valve core through hole 19, the quality of fit and the surface working precision of having relatively high expectations when guaranteeing the fluid sealing, allow axle core 3 in valve core through hole 19, to rotate freely with axially displaced, the change of axial location realizes by the quantity of regulating location gauge block 16, be axle center, poppet shaft to position change 18, thereby realize that pressure transducer hole 13 is relative with axial different throttling channels bottom surface pressure measurement aperture 11 or oil back chamber pressure measurement aperture 20; The relative spool rotation 22 in axle center realizes that the throttling channel bottom surface pressure measurement aperture 11 or the oil back chamber pressure measurement aperture 20 that pressure transducer hole 13 and week make progress different are relative.Spool 2 cooperates in the valve body 1 of packing into after installing in axle core 3, realizes and the axial location of valve body 1 by dog screw 6, promptly adjusts the axial mutual alignment between valve body boss 14 and the throttling channel 10, thereby realizes the adjusting of throttle opening.In throttling valve when work,, hydraulic pressure has from oil-in 8 and flows to, and flows out from oil-out 9 by entering oil back chamber 17 after throttling channel 10 throttling actions again.Produce air pocket in throttling channel 10 throttling processes, cause noise and vibration.When throttle opening was big, air pocket produced along valve body 2 throttling limits 23, and extends downstream, direction deflection spool 2 walls in the extension process, and the air pocket wake flow comes off, and crumbles and fall at spool 2 walls, causes a large amount of high frequency noises and vibration.Throttle opening hour, air pocket directly produces in throttling channel 10 bottom wall, its wake flow points to spool 2 walls equally, the feature that crumbles and fall is identical.Learn with the characteristics of crumbling and fall that according to above-mentioned air pocket generation the nearly spool wall pressure situation and the air pocket origin cause of formation and variation tendency are in close relations.As shown in Figure 2, spool 2 walls are offered throttling channel bottom surface pressure measurement aperture 11 and oil back chamber pressure measurement aperture 20, communicate with liquid.Axle core wall has two above pressure transducer holes 12, in high-frequency pressure sensor 13 is housed.After pressure transducer hole 12 aligns with throttling channel bottom surface pressure measurement aperture 11 or oil back chamber pressure measurement aperture 20, high-frequency pressure sensor 13 will communicate with spool 2 wall liquid, and then realize pressure survey.Shown in Fig. 3,4,5,6, the use of two above high-frequency pressure sensor 13 can obtain pressure distribution situation of change in larger scope.High-frequency pressure sensor 13 is equally spaced along axle core 3 axis directions, during air pocket wake flow process spool wall flow further downstream, the pressure surge of different spool 2 wall high-frequency pressure sensor 13 situation of change in time will directly reflect the characteristics such as the frequency that crumbles and fall, amplitude of air pocket wake flow, and these have directly reflected the magnitude of Cavitation Noise and vibration.But high-frequency pressure sensor 13 the highest measured frequencies are 100kHz, the high frequency sound requirement of satisfying that Cavitation Noise and air pocket wake flow come off etc.
Claims (5)
1. the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of an axle core, it is characterized in that: valve body (1) is fixed on the valve seat (4), spool (2) is packed in the valve body (1), axle core (3) cooperates with valve core through hole (19), axle core (3) can rotate in valve core through hole (19) and axially relative displacement, the both sides of valve seat (4) are installing and locating plate (5) respectively, dog screw (6) on two location-plates (5) withstands on the both ends of the surface of spool (2) respectively, location gauge block (16) is installed between the axle core (3) and spool (2) end face of a side, adjusting location gauge block (16) is determined the axial location between spool (2) and the axle core (3), spool (2) wall normal direction has throttling channel bottom surface pressure measurement aperture (11) and oil back chamber pressure measurement aperture (20), distributes vertically more than 3 groups; Axle core (3) wall normal direction has pressure transducer hole (12), distributes vertically more than two; High-frequency pressure sensor (13) is equipped with in inside, pressure transducer hole (12), and the signal wire (21) of pressure transducer hole (12) joins through axle core deep hole (15) and extraneous data acquisition system (DAS) (24).
2. the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle core according to claim 1, it is characterized in that: described oil back chamber pressure measurement aperture (20) distributes more than six along central angles such as circumference, and is equally spaced vertically more than three groups; Throttling channel bottom surface pressure measurement aperture (11) is symmetrically distributed in throttling channel (10) both sides, bottom surface, and axial spacing equates, throttling channel bottom surface pressure measurement aperture (11) center line and axle core (2) axes intersect; Axial line distance all equates between adjacent segments chute pressure measurement aperture (11) axial distance, adjacent oil back chamber pressure measurement aperture (20) axial distance and adjacent segments chute pressure measurement aperture (11) and the oil back chamber pressure measurement aperture (20), be 2.0～3.0mm, hole diameter 0.1～0.5mm.
3. the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle core according to claim 1 is characterized in that: described pressure transducer hole (12) is offered along axle core (3) wall normal direction, distributes vertically more than two; Pressure transducer hole (12) spacing equates that with throttling channel pressure measurement aperture (11) axial spacing pressure transducer hole (12) spacing equates with oil back chamber pressure measurement aperture (20) axial spacing; Pressure transducer hole (12) diameter 0.5～1.0mm is greater than the diameter of throttling channel pressure measurement aperture (11) and oil back chamber pressure measurement aperture (20).
4. the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle core according to claim 1, it is characterized in that: described location gauge block (16) thickness equates with throttling channel pressure measurement aperture (11) axial spacing that all location gauge block (16) thickness equate with oil back chamber pressure measurement aperture (20) axial spacing; During initial alignment, when promptly not having location gauge block (16), top pressure measurement aperture (11) is identical with pressure transducer hole, top (12) axial location.
5. the portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle according to claim 1 core is characterized in that: the highest response frequency 100kHz of described high-frequency pressure sensor (13), satisfy the frequency requirement of Cavitation Noise research; Two high-frequency pressure sensor (13) are used simultaneously, satisfy the requirement on experimental period and the space.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200810063193XA CN100565150C (en) | 2008-07-22 | 2008-07-22 | The portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200810063193XA CN100565150C (en) | 2008-07-22 | 2008-07-22 | The portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle core |
Publications (2)
| Publication Number | Publication Date |
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| CN101329214A true CN101329214A (en) | 2008-12-24 |
| CN100565150C CN100565150C (en) | 2009-12-02 |
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| CNB200810063193XA Expired - Fee Related CN100565150C (en) | 2008-07-22 | 2008-07-22 | The portable nearly hydraulic valve core wall surface flow field pressure dynamic measurement device of axle core |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106125834A (en) * | 2016-06-21 | 2016-11-16 | 中兴通讯股份有限公司 | Electronic equipment and signal detecting method |
| CN106768608A (en) * | 2016-12-21 | 2017-05-31 | 安徽天利粮油集团股份有限公司 | Dryer pressure monitoring device |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101963538B (en) * | 2010-07-20 | 2012-02-01 | 南京工业大学 | Internal flow field pressure measuring device for hydraulic slide valve cavity body |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5406979A (en) * | 1986-06-16 | 1995-04-18 | Acf Manufacturing, Inc. | Valve and sensor arrangement |
| US5588462A (en) * | 1986-06-16 | 1996-12-31 | Agf Manufacturing, Inc. | Valve and sensor arrangement |
| DE29505320U1 (en) * | 1995-03-29 | 1995-05-24 | Postberg, Anne-Karin Maria, 63486 Bruchköbel | Shut-off valve for a measuring device |
| US5611256A (en) * | 1995-12-05 | 1997-03-18 | Chung; Chang S. | Differential pressure detecting system |
| US20040237637A1 (en) * | 2003-01-17 | 2004-12-02 | Andre Veinotte | Flow sensor for purge valve diagnostic |
| CN2745059Y (en) * | 2004-06-30 | 2005-12-07 | 宝山钢铁股份有限公司 | Four-way three-step servo valve core and valve pocket detecting device |
| US20060174948A1 (en) * | 2005-02-08 | 2006-08-10 | Deere & Company, A Delaware Corporation | Valve spool position sensor |
-
2008
- 2008-07-22 CN CNB200810063193XA patent/CN100565150C/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106125834A (en) * | 2016-06-21 | 2016-11-16 | 中兴通讯股份有限公司 | Electronic equipment and signal detecting method |
| CN106768608A (en) * | 2016-12-21 | 2017-05-31 | 安徽天利粮油集团股份有限公司 | Dryer pressure monitoring device |
| CN106768608B (en) * | 2016-12-21 | 2024-04-05 | 安徽天利粮油集团股份有限公司 | Dryer pressure monitoring device |
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| CN100565150C (en) | 2009-12-02 |
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Granted publication date: 20091202 Termination date: 20130722 |