CN105757304A - High-precision flow servo control valve - Google Patents
High-precision flow servo control valve Download PDFInfo
- Publication number
- CN105757304A CN105757304A CN201610302802.7A CN201610302802A CN105757304A CN 105757304 A CN105757304 A CN 105757304A CN 201610302802 A CN201610302802 A CN 201610302802A CN 105757304 A CN105757304 A CN 105757304A
- Authority
- CN
- China
- Prior art keywords
- venturi tube
- flow
- ball screw
- precision
- cone governor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
- F16K17/20—Excess-flow valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/02—Actuating devices; Operating means; Releasing devices electric; magnetic
- F16K31/04—Actuating devices; Operating means; Releasing devices electric; magnetic using a motor
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Flow Control (AREA)
Abstract
The invention discloses a high-precision flow servo control valve applicable to a liquid pipeline. The high-precision flow servo control valve comprises a servo motor, a ball screw, an adjusting taper and a combined seam type venturi tube. The control valve is compact in design; due to design of the size of the combined seam type venturi tube, the flow variation and the linearity of the stroke of the adjusting taper are optimized, the precision and the stability of flow control are improved, and the control precision is also improved due to the data processing characteristics of a Dsp mainboard. The venturi tube and a valve body are made of high-strength corrosion-resistant stainless steel, a valve element is made of a copper alloy and is sealed by a nitrile rubber pad, and a limiting block is made of LY12 aluminum alloy. Due to adoption of the combined seam type venturi tube, when the inlet pressure varies within a range of 3-10MPa and the hydrogen peroxide output flow is greater than 100 g/s, the error can be controlled to be within a range of 0.1%, and the flow stability of an aerial conveying system can be ensured.
Description
Technical field
The present invention designs control valve, specifically, is a kind of high-precision flow pilot valve.
Background technology
Flow control valve is under certain inlet pressure, relies on the size changing throttling oral fluid resistance to control the flow of throttle orifice,
Ensure that the flow of circulation meets design requirement.
In rocket propulsion field, flow control valve is used for regulating the flow that tank inner oxidizing agent and fuel supply to combustion chamber, due to
The requirements such as the change propulsive to rocket, need to carry out supply flow rate certain control, to realize intended function, if to flow
Regulation do not reach certain requirement, influence whether the design performance of rocket engine.
For squash type solid-liquid rocket induction system, typically carried out the control of flow by Venturi tube, but due to Wen
The action principle of pipe is that the pressure reduction by upstream and downstream controls flow, although and generally upstream and downstream pressure reduction can be by certain
Structure be controlled by, but precision is the highest.In real work, flow control valve requires have certain structural strength and higher essence
Degree.
Summary of the invention
In order to solve the problems referred to above, patent of the present invention provides a kind of high-precision flow pilot valve, including shell, servo electricity
Machine, ball screw, cone governor, valve body, Venturi tube, sensor.Wherein, shell bottom, valve body are with Venturi tube from the bottom to top
Fix successively；Servomotor is fixed on shell bottom.
Described ball screw is arranged in shell, and it is the cone governor of conical section that ball screw is installed top；The conical section of cone governor
It is positioned at the fluid passage of Venturi tube；Valve inner is provided with sap cavity, and has feed pathway；Propellant enters through feed pathway
Sap cavity, is rotated by screw mandrel in driven by servomotor ball screw, and then drives cone governor to be axially moveable, in regulation Venturi tube
Fluid passage circulation area, make propellant enter fluid passage being flowed out by venturi outlet end；When cone governor is positioned at upwards
During extreme position, the liquid feeding end of Venturi tube is blocked by cone governor.
After Dsp development board obtains flow sensor input, according to the real-time traffic recorded, pid algorithm is used to control servomotor
Motion, the transmission rotating through ball screw of servomotor becomes direct acting, thus changes the position of cone governor so that Wen
Flow area in pipe changes, and plays the effect of flow-control.
The advantage of patent of the present invention is:
1, high-precision flow pilot valve of the present invention, the combination using flow sensor, Dsp mainboard and servomotor can be real
Now to the detection of real-time traffic in Venturi tube and control, the data processing function that Dsp mainboard is powerful, the servo electricity of combined high precision
Machine so that servomotor drives the speed of ball screw and cone governor to be in the magnitude of 0.01mm, add cone governor and
The combination of Venturi tube, can obtain higher flow control accuracy.
2, high-precision flow pilot valve of the present invention, can be processed by Dsp mainboard and set or monitoring data, control motor and turn
Dynamic, rely on the requirement that can meet changes in flow rate occasion causing Venturi tube flow area；
3, high-precision flow pilot valve of the present invention, uses incremental digital PID control algorithm, it is ensured that stablizing of servomotor work,
And then ensure stablizing of Flow-rate adjustment regulation.
4, high-precision flow pilot valve of the present invention, venturi tube flow is only relevant with inlet pressure so that controlling flow supply
When more simple and effective.
Accompanying drawing explanation
Fig. 1 is high-precision flow pilot valve structure chart of the present invention；
Fig. 2 is cone governor structural representation in high-precision flow pilot valve of the present invention.
In figure:
1-shell 2-servomotor 3-ball screw
4-cone governor 5-valve body 6-Venturi tube
7-sensor 8-Dsp mainboard 9-motor driver
10-sap cavity 11-rubber seal 12-rubber gasket
101-circular orientation boss A 301-screw mandrel 302-nut
401-cylindrical section 402-conical section 403-base
404-adpting flange 501-circular orientation boss B 502-liquid outlet channel
Specific embodiments
Below in conjunction with the accompanying drawings patent of the present invention is described further.
High-precision flow pilot valve of the present invention, including shell 1, servomotor 2, ball screw 3, cone governor 4, valve body
5, Venturi tube 6, sensor 7, Dsp mainboard 8 and motor driver 9, as shown in Figure 1.
Described shell 1 is tubular structure, uses LY12 aluminium alloy to make；Servomotor 2 is coaxially disposed with shell 1, front end
Circumferentially fixed it is arranged on shell 1 end, makes the output shaft of servomotor 2 be positioned at shell 1.Ball screw 3 is arranged at shell
In 1, the screw mandrel 301 of ball screw 3 is coaxially connected with the output shaft of servomotor 2 by shaft coupling.The spiral shell of ball screw 3
Female 302 circumferences coordinate with ring-side wall in the circular orientation boss A101 of design in shell 1 front inner wall, limit ball screw 3
Move radially.
Described cone governor 4 generally rod-like structure, uses intensity 316 stainless steels high, corrosion resistant to make, and bottom is cylindrical section
401, top is conical section 402, as shown in Figure 2.Cone governor 4 bottom is designed with base 403, and base 403 has recess cavity,
Global sections is inverted U.It is designed with adpting flange 404 in base 403 circumference.Cone governor 4 is coaxially disposed with ball screw 3,
It is fixed on the nut 302 of ball screw 3 by adpting flange 404.From there through the rotation of screw mandrel 301 in ball screw 3
Nut 302 can be driven together to move with cone governor 4, and when nut 302 moves downward, screw mandrel 3 can extend into base 403
Recess cavity in, and by recess cavity also realize cone governor 4 is moved spacing.
Valve body 5 is tubular structure, and internal diameter is more than the diameter of cone governor 4, and coaxial sleeve is outside cone governor 4, outside bottom is fixed on
On the front end face of shell 1.Valve body 5 indoor design has circular orientation boss B501, ring-side wall and tune in circular orientation boss B501
In the middle part of pitch cone 4, outer wall circumference coordinates, and arranges rubber gasket 12 realization sealing between the two；By circular orientation boss B501
Limit moving radially of cone governor 4.Venturi tube 6 uses intensity 316 stainless steels high, corrosion resistant to make, internal coaxial design
There is fluid passage；Venturi tube 6 is coaxially plugged on valve body 5 top, and Venturi tube 6 is by its liquid feeding end end and valve body 5 inwall
The annular shoulder of design coordinates location, and arranges rubber seal 11 realization sealing between the two.Owing to valve body 5 internal diameter is more than regulation
The diameter of cone 4, therefore circular orientation boss B501 within the liquid feeding end of Venturi tube 6, valve body 5 and shape between valve body 5 inwall
Sap cavity 7, sap cavity 7 is become to connect with the feed pathway 502 of design on valve body 5.
In above-mentioned pilot valve, when in ball screw 3, nut 302 is positioned at screw mandrel 301 top, the conical section of cone governor 4
402 fluid passages being positioned at Venturi tube 6, make cylindrical section 403 upper end be positioned at the fluid passage of Venturi tube 6 simultaneously, pass through
The liquid feeding end of Venturi tube 6 is blocked by cylindrical section 403.Hydrogen peroxide propellant feed pathway 502 on valve body 5 enters sap cavity
7, move by controlling servomotor 2, drive screw mandrel 301 to rotate, make nut 302 move down along screw mandrel 301, cone governor
4 move down in the lump, and now the cylindrical section 401 of cone governor 4 progressively disengages the liquid feeding end of Venturi tube 6, thus in sap cavity 7
Hydrogen peroxide propellant is adjusted the gap between conical section 402 sidewall of cone 4 and the liquid feeding end of Venturi tube 6 and enters Venturi tube 6
Fluid passage, is finally flowed out by the outlet end of Venturi tube.By controlling servomotor 2 counter motion, drive in ball screw 3
Screw mandrel 301 rotates backward, and makes nut 302 move upward along screw mandrel, cone governor 4 moves upward in the lump, now cone governor 4
Cylindrical section 401 inserts the liquid feeding end of Venturi tube 6, is blocked by the liquid feeding end of Venturi tube 6, now, and the confession of hydrogen peroxide propellant
Give and stop.To sum up, by the up and down motion of control and regulation cone 4, supply and the stopping supply of hydrogen peroxide propellant can be realized
Function；Simultaneously when hydrogen peroxide propellant supplies, by the displacement of the up and down motion of control and regulation cone 4, cone can be realized
Gap size regulation between shape section 402 sidewall and Venturi tube 6 liquid feeding end, and then realize hydrogen peroxide propellant at Venturi tube 6
Circulation area regulation in fluid passage, finally realizes the Flow-rate adjustment of hydrogen peroxide propellant.
Described sensor 7 is flow sensor, is arranged on the feeding pipe of propellant, flows through valve body 5 liquid for Real-time Collection
The mass flow data of the propellant in chamber；DPS mainboard 8 is used for receiving the mass flow data that sensor gathers, it is judged that its with set
The difference of constant flow, and then according to this difference, use pid algorithm to control the motion of servomotor 2, adjust the position of cone governor 4
Put, the circulation area of Venturi tube 6 is increased or decreased so that flow value is close to setting flow value.
The sensor 7 uses four-wire system, and wherein 1,2 terminals are 24V voltage input-terminal, and 3,4 terminals are RS-485 number
According to lead-out terminal, directly data on flows can be gathered by Dsp mainboard 8.
Dsp mainboard 8 is based on Digital Signal Processing, and data-interface is RS-485, by this interface by the number after analyzing and processing
According to passing to motor driver 9, motor driver 9 send pulse signal and drive servomotor 2 to work, servomotor 2
Angular displacement can be precisely controlled by pulse signal, and single step precision can be at about 0.01mm.
In the present invention, the fluid passage of Venturi tube 6 includes expansion segment and contraction section, and the angle of flare of expansion segment is 6 °～10 °, expands
Zhang Duanwei outlet end；The convergency of contraction section is 25 °～40 °, and contraction one end is liquid feeding end, and above-mentioned expansion segment is short with contraction
Connect, joint a diameter of 4～6mm.Venturi tube 6 endoperoxides Hydrogen propellant upstream pressure is 5Mpa when, peroxide
The biggest quality flow rate changing Hydrogen propellant is 767g/s.Conical section 402 cone angle of design cone governor 4 is 8 °～10 ° simultaneously, cone
High 5～8mm.The stroke of the flow and cone governor 4 that now flow through Venturi tube 6 has goodish linear relationship, and is flowing
During pressure change, discharge coefficient changes hardly, is conducive to improving the precision of Flow-rate adjustment.
Claims (5)
1. a high-precision flow pilot valve, it is characterised in that: include shell, servomotor, ball screw, cone governor,
Valve body, Venturi tube, sensor；Wherein, shell bottom, valve body are fixed the most successively with Venturi tube；Servomotor is fixed
In shell bottom；
Described ball screw is arranged in shell, and it is the cone governor of conical section that ball screw is installed top；The conical section of cone governor
It is positioned at the fluid passage of Venturi tube；Valve inner is provided with sap cavity, and has feed pathway；Propellant enters through feed pathway
Sap cavity, is rotated by screw mandrel in driven by servomotor ball screw, and then drives cone governor to be axially moveable, in regulation Venturi tube
Fluid passage circulation area, make propellant enter fluid passage being flowed out by venturi outlet end；When cone governor is positioned at upwards
During extreme position, the liquid feeding end of Venturi tube is blocked by cone governor.
2. as claimed in claim 1 a kind of high-precision flow pilot valve, it is characterised in that: by sensor, Dsp mainboard with
Motor driver carries out flow-control；Wherein, sensor is arranged on the feeding pipe of propellant, flows through valve for Real-time Collection
The mass flow data of the propellant in body fluid chamber；DSP mainboard be used for receive sensor gather mass flow data, it is judged that with set
The difference of constant flow, by motor driver according to this difference, drives servomotor work.
3. a kind of high-precision flow pilot valve, it is characterised in that: described cone governor is set by bottom
The base of meter is fixed with the nut in ball screw, particularly as follows: base is the inverted U cross section structure with recess cavity；Circumference sets
In respect of adpting flange；It is fixed on the nut of ball screw by adpting flange；And in nut motion process, screw mandrel is recessed
Stretch in chamber.
4. a kind of high-precision flow pilot valve, it is characterised in that: the nut week of described ball screw
Coordinate to the circular orientation boss A madial wall of design on outer casing inner wall, limit moving radially of ball screw.
5. a kind of high-precision flow pilot valve, it is characterised in that: it is fixed that valve inner is designed with annular
Position boss B, in circular orientation boss B, ring-side wall coordinates with cone governor outer wall circumference, limits regulation by circular orientation boss B
Moving radially of cone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610302802.7A CN105757304A (en) | 2016-05-09 | 2016-05-09 | High-precision flow servo control valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610302802.7A CN105757304A (en) | 2016-05-09 | 2016-05-09 | High-precision flow servo control valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105757304A true CN105757304A (en) | 2016-07-13 |
Family
ID=56323747
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610302802.7A Pending CN105757304A (en) | 2016-05-09 | 2016-05-09 | High-precision flow servo control valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105757304A (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106090388A (en) * | 2016-08-26 | 2016-11-09 | 湖北益健堂科技股份有限公司 | Electrical adjustment flow valve |
| CN108799229A (en) * | 2018-07-02 | 2018-11-13 | 燕山大学 | The long centrum spool numerical controlled voltage valve of Small Taper |
| CN110101442A (en) * | 2019-05-09 | 2019-08-09 | 宋月霞 | One kind being directed to clinical obstetrics with anti-outer-flowing type film breaking unit |
| CN111916926A (en) * | 2019-05-09 | 2020-11-10 | 博格华纳公司 | Electric connector and control valve comprising same |
| CN112032310A (en) * | 2020-07-27 | 2020-12-04 | 北京精密机电控制设备研究所 | High-precision gas mass flow control valve |
| CN112065605A (en) * | 2020-09-29 | 2020-12-11 | 航天科工火箭技术有限公司 | Variable thrust pump pressure type liquid rocket engine system |
| CN112211751A (en) * | 2020-09-17 | 2021-01-12 | 航天科工火箭技术有限公司 | Adjustable cavitation venturi |
| CN112746911A (en) * | 2020-12-29 | 2021-05-04 | 上海空间推进研究所 | Variable thrust engine flow regulating device and on-orbit protection method |
| CN112879180A (en) * | 2021-03-02 | 2021-06-01 | 北京航空航天大学 | Compact pintle injector adjustment mechanism |
| CN113090415A (en) * | 2021-04-13 | 2021-07-09 | 西北工业大学 | Variable flow solid-liquid mixing engine |
| CN113110627A (en) * | 2021-04-28 | 2021-07-13 | 北京航空航天大学 | High-precision, high-reliability and quick-response adjustable venturi |
| CN113124943A (en) * | 2021-04-28 | 2021-07-16 | 北京航空航天大学 | High-precision adjustable venturi based on grating ruler feedback |
| CN113175532A (en) * | 2021-04-28 | 2021-07-27 | 北京航空航天大学 | Adjustable cavitation venturi |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4134572A (en) * | 1977-02-16 | 1979-01-16 | Schmidt Alfred C | Adjustable flow metering orifice |
| US5538027A (en) * | 1995-04-11 | 1996-07-23 | Adamson; Keith W. | Pressure balancing foam valve |
| CN101799025A (en) * | 2009-05-15 | 2010-08-11 | 武汉科技学院 | Internal feedback type incremental hydraulic throttling digital valve |
| CN201827473U (en) * | 2010-03-31 | 2011-05-11 | 张国臣 | Cavitation venturi adjusting valve |
| CN102829010A (en) * | 2012-08-16 | 2012-12-19 | 北京润菲利德科技有限公司 | Directly moving type high-flow directional flow servo valve and control system using servo valve |
-
2016
- 2016-05-09 CN CN201610302802.7A patent/CN105757304A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4134572A (en) * | 1977-02-16 | 1979-01-16 | Schmidt Alfred C | Adjustable flow metering orifice |
| US5538027A (en) * | 1995-04-11 | 1996-07-23 | Adamson; Keith W. | Pressure balancing foam valve |
| CN101799025A (en) * | 2009-05-15 | 2010-08-11 | 武汉科技学院 | Internal feedback type incremental hydraulic throttling digital valve |
| CN201827473U (en) * | 2010-03-31 | 2011-05-11 | 张国臣 | Cavitation venturi adjusting valve |
| CN102829010A (en) * | 2012-08-16 | 2012-12-19 | 北京润菲利德科技有限公司 | Directly moving type high-flow directional flow servo valve and control system using servo valve |
Non-Patent Citations (2)
| Title |
|---|
| 周汉申: "《单组元液体火箭发动机设计与研究》", 31 August 2009, 中国宇航出版社 * |
| 沙占友等: "《新型专用数字仪表原理与应用》", 30 April 2006, 机械工业出版社 * |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106090388A (en) * | 2016-08-26 | 2016-11-09 | 湖北益健堂科技股份有限公司 | Electrical adjustment flow valve |
| CN108799229A (en) * | 2018-07-02 | 2018-11-13 | 燕山大学 | The long centrum spool numerical controlled voltage valve of Small Taper |
| CN110101442A (en) * | 2019-05-09 | 2019-08-09 | 宋月霞 | One kind being directed to clinical obstetrics with anti-outer-flowing type film breaking unit |
| CN111916926A (en) * | 2019-05-09 | 2020-11-10 | 博格华纳公司 | Electric connector and control valve comprising same |
| CN112032310A (en) * | 2020-07-27 | 2020-12-04 | 北京精密机电控制设备研究所 | High-precision gas mass flow control valve |
| CN112211751A (en) * | 2020-09-17 | 2021-01-12 | 航天科工火箭技术有限公司 | Adjustable cavitation venturi |
| CN112065605A (en) * | 2020-09-29 | 2020-12-11 | 航天科工火箭技术有限公司 | Variable thrust pump pressure type liquid rocket engine system |
| CN112746911A (en) * | 2020-12-29 | 2021-05-04 | 上海空间推进研究所 | Variable thrust engine flow regulating device and on-orbit protection method |
| CN112746911B (en) * | 2020-12-29 | 2022-07-19 | 上海空间推进研究所 | Variable thrust engine flow regulating device and on-orbit protection method |
| CN112879180A (en) * | 2021-03-02 | 2021-06-01 | 北京航空航天大学 | Compact pintle injector adjustment mechanism |
| CN113090415A (en) * | 2021-04-13 | 2021-07-09 | 西北工业大学 | Variable flow solid-liquid mixing engine |
| CN113110627A (en) * | 2021-04-28 | 2021-07-13 | 北京航空航天大学 | High-precision, high-reliability and quick-response adjustable venturi |
| CN113124943A (en) * | 2021-04-28 | 2021-07-16 | 北京航空航天大学 | High-precision adjustable venturi based on grating ruler feedback |
| CN113175532A (en) * | 2021-04-28 | 2021-07-27 | 北京航空航天大学 | Adjustable cavitation venturi |
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Application publication date: 20160713 |