WO2000029812A2 - Piezo-resistive position indicator - Google Patents
Piezo-resistive position indicator Download PDFInfo
- Publication number
- WO2000029812A2 WO2000029812A2 PCT/US1999/027412 US9927412W WO0029812A2 WO 2000029812 A2 WO2000029812 A2 WO 2000029812A2 US 9927412 W US9927412 W US 9927412W WO 0029812 A2 WO0029812 A2 WO 0029812A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sensor
- actuating
- valve
- accordance
- output signal
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/02—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using mechanical means
- G01D5/04—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using mechanical means using levers; using cams; using gearing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/003—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring position, not involving coordinate determination
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
- G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
- G01D5/16—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying resistance
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/0318—Processes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8158—With indicator, register, recorder, alarm or inspection means
- Y10T137/8225—Position or extent of motion indicator
- Y10T137/8242—Electrical
Definitions
- TECHNICAL FIELD This invention relates generally to position sensing systems and in particular to a system for and method of detecting valve position.
- Fluid transfer systems such as aircraft environmental control systems, extensively employ valves for delivery and regulation of engine bleed air for such purposes as passenger cabin pressurization and temperature control. Any failure of a valve to open or close will negatively affect environmental control system performance and, in some instances, affect aircraft dispatchability.
- valve failures can sometimes be calculated via measurements of the temperature and pressure of the bleed air, such failure detection schemes tend to be elaborate and require significant testing and analysis to ensure adequate function. Further, implementation of algorithms needed for such calculations increase development costs, airplane down time and retrofit cost. It is desirable to detect valve failure when the airplane is grounded and the systems are off.
- the preferred approach to valve failure detection is deterministic position indication through the use of valve position sensing instruments. With respect to such instruments, the position indicator, wiring, and interface circuit associated therewith, ideally, are cost effective, lightweight, interchangeable and able to operate in engine environments of severe vibration and temperature. Moreover, it is preferable to use a standardized design for all valve applications to achieve commonality and mass economy.
- a sensor beam provides a linear or non-linear continuous signal to a computer that translates the signal into a valve position reading.
- a sensor beam incorporating piezo- resistive components forming a Wheatstone bridge abuts a cam mounted on a butterfly valve spindle. Valve movement causes rotation of the cam that, in turn, imparts a bending moment to the Wheatstone bridge. This bending moment strains the piezo-resistive components, thereby altering the resistance of the Wheatstone bridge.
- the computer measures the resistance change by means of an output signal transmitted by the sensor beam and calculates valve position based thereon.
- FIG. 1 is a cross-sectional view of a valve portion of an aircraft environmental control system incorporating features of the present invention
- FIG. 2A is a cross-sectional view taken along Line 2-2 as depicted in FIG. 1;
- FIG. 2B is a view analogous to FIG. 2A depicting bending of a sensor beam by a cam according to principles of the present invention
- FIG. 3 is a partial split plan view of the top surface and bottom surface of a sensor beam incorporating features of the present invention
- FIG. 4 is an electrical schematic depiction of a preferred embodiment piezo-resistive Wheatstone bridge incorporated by a sensor beam incorporating features of the present invention
- FIG. 5 is a cross-sectional view analogous to that of FIG. 2A of an alternative embodiment of the present invention.
- FIG. 6 is a cross-sectional view of an alternative embodiment valve incorporating features of the present invention.
- FIG. 1 is a cross-sectional view of a valve portion of an aircraft environmental control system 10.
- Environmental control system 10 includes a pipe 20 through which fluid, such as air, may flow.
- the regulation of fluid flow through pipe 20 is controlled by a butterfly valve 30.
- Butterfly valve 30 comprises a valve member, such as a disk 40, which, in a closed position, blocks fluid flow through pipe 20, a drive spindle 50 and a dynamic seal, such as an elastomeric seal 60.
- Valve disk 40 is caused to rotate by means of an actuator (not shown) connected to drive spindle 50, the rotational torque being transmitted to disk 40 by drive spindle 50.
- Disk 40 is drivably connected to a lower end 80 of drive spindle 50 and is free to rotate within pipe 20.
- seal 60 engages the periphery of disk 40, thereby sealing off flow of fluid through pipe 20.
- seal 60 may be excluded such that no seal is created when valve 30 is in the closed position.
- an actuating member such as a substantially oblong or elliptical cam 90, disposed within an enclosure 100 and depicted in FIG. 1 with broken lines.
- cam 90 is circular and eccentrically mounted on spindle 50.
- Cam 90 at all times rotates on spindle 50 coincidentally with rotation of disk 40.
- Cam 90 abuts a sensor beam 110 fixably mounted within enclosure 100 by means of a clamp 160.
- beam 110 comprises a thin sheet metal substrate having a first portion 112 extending outwardly from clamp 160.
- beam 110 disposed upon beam 110 are piezo-resistive components, the resistance of which changes when strained, that are coated with and fixed by means of glass or ceramic.
- the advantages of constructing beam 110 in this manner are described in detail in the '048 patent.
- the ceramics/glasses used in this invention have a high temperature refiring capability
- the preferred embodiment beam 110 exhibits a composite thermal coefficient of expansion which is optimum for use in electronic devices, and exhibits a low dielective constant which allows for use with high frequency circuits and allows for greater applicability in electronic applications.
- the ceramics/glasses used in this invention exhibit strong adhesion to the metal substrate after firing and are very resistant to thermal stress. This avoids breakdown of beam 110 when exposed to high temperatures normally encountered in engine environments and/or the operation of electronic devices.
- Beam 110 electrically communicates an output signal through lead wires 120 to a computer or other display or read device represented by box 111 in Fig. 1.
- the arrangement of piezo-resistive components incorporated by beam 110 is such as to form a Wheatstone bridge, although other similarly functioning circuit configurations may be substituted.
- the Wheatstone bridge comprises an input 140, a ground 150, a pair of outputs 155A, 155B, eight terminals 145A, 145B, 145C, 145D, 145E, 145F, 145G, 145H, and four piezo-resistors Rl, R2, R3, R4.
- terminal 145D are situated on top surface 157 of beam 110 and piezo-resistors R2, R4 and terminals 145E, 145F, 145G, 145H are situated on bottom surface 158 of beam 110.
- terminal 145 A is electrically connected to terminal 145H
- terminal 145B is electrically connected to terminal 145E
- terminal 145C is electrically connected to terminal 145F
- terminal 145F is electrically connected to terminal 145F
- Connector means 156 may be standard electrical wiring or any other similarly functioning device known in the art.
- a continuous supply of input voltage from a voltage supply represented by 113 in Fig. 1 may be supplied to beam 110 through clamp 160 via input 140 and returns to outputs 155 A, 155B as an output voltage or signal. The value of this output signal is a function of the effective resistance of beam 110 created by the Wheatstone bridge. Because beam 110 is fixed by clamp 160, as shown in FIGS.
- beam 110 behaves as a cantilever beam such that when first portion 112 is bent or otherwise deflected by means of cam 90, piezo-resistors Rl, R2, R3, R4 are strained resulting in a change in the effective resistance of beam 110.
- cam 90 imparts a corresponding bending moment-induced strain upon first portion 112.
- first portion 112 at its point of contact with cam 90, is deflected a maximum distance of 0.1 inch.
- a continuous supply of direct current input voltage is supplied to beam 110.
- the effective resistance of beam 110 is altered, thereby causing a corresponding change in value of the output signal.
- a computer 111 may be used to readily convert the measured resistance change in beam 110 into a corresponding position of disk 40 within pipe 20. By determining the position of disk 40 within pipe 20, it may then be determined whether or not and the rate at which fluid is flowing through pipe 20.
- a biasing apparatus such as a pre-load spring 170, may apply an applicator pad 180 to beam 110 opposite cam 90.
- Spring 170 and pad 180 function to force abutment of beam 110 against cam 90 throughout the rotation range of cam 90, thereby doubling the output signal from beam 110 and increasing the accuracy of sensing the position of disk 40.
- FIG. 6 illustrates the manner in which principles of the present invention may be applied to a conventional flexduct valve 190. In ordinary operation, pressurized fluid enters flexduct valve 190 through an inlet 200 and is exhausted out of flexduct valve 190 through an outlet 210.
- Pressurization of an accessory is achieved by aligning outlet 210 with a receiver groove 220, thereby enabling the accessory to receive pressured working fluid from groove 220.
- a valve driver 230 is used to push flexduct valve outlet 210 out of alignment with receiver groove 220.
- upward pressure applied to flexduct valve 190 by valve driver 230 causes a bumper element 240 attached to flexduct valve 190 to forcefully contact a sensor beam 250 of substantially identical composition and function as that of beam 110 discussed above.
- beam 250 is deflected by an amount proportional to displacement of flexduct valve 190. Deflection of beam 250 may then be measured, in a manner similarly described above, as a means of determining the extent of misalignment, and thus absence of fluid communication, between flexduct outlet 210 and receiver groove 220.
- the present invention is not limited to cooperation with valves, but can also be used with actuators or throttles.
- the function of beam 110 can be adapted by various known mechanical devices such as cams, levers or linkages to convert rotary or linear movement to a small displacement that can be measured within the elastic range of the beam- Wheatstone bridge combination. It is intended that the scope of the invention not be limited in any way to the illustrative and alternative embodiments shown and described but that the invention be limited only by the claims appended hereto.
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000582766A JP2002530635A (en) | 1998-11-18 | 1999-11-18 | Position detection device |
EP99960489A EP1135666B1 (en) | 1998-11-18 | 1999-11-18 | Piezo-resistive position indicator |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10897698P | 1998-11-18 | 1998-11-18 | |
US60/108,976 | 1998-11-18 | ||
US09/358,773 US6308723B1 (en) | 1998-11-18 | 1999-07-22 | Piezo-resistive position indicator |
US09/358,773 | 1999-07-22 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2000029812A2 true WO2000029812A2 (en) | 2000-05-25 |
WO2000029812A3 WO2000029812A3 (en) | 2000-10-05 |
Family
ID=26806503
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1999/027412 WO2000029812A2 (en) | 1998-11-18 | 1999-11-18 | Piezo-resistive position indicator |
Country Status (5)
Country | Link |
---|---|
US (1) | US6308723B1 (en) |
EP (1) | EP1135666B1 (en) |
JP (1) | JP2002530635A (en) |
ES (1) | ES2257091T3 (en) |
WO (1) | WO2000029812A2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015105872A (en) * | 2013-11-29 | 2015-06-08 | タイコエレクトロニクスジャパン合同会社 | Rotation angle detection sensor and throttle device of internal combustion engine |
JP2015105871A (en) * | 2013-11-29 | 2015-06-08 | タイコエレクトロニクスジャパン合同会社 | Rotation angle detection sensor and throttle device of internal combustion engine |
WO2020016326A1 (en) | 2018-07-18 | 2020-01-23 | Université De Montpellier | Omnidirectional sensor for determining an environmental value of a pivoting object |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6807875B2 (en) | 2000-12-01 | 2004-10-26 | Honeywell International Inc. | Self-compensating position sensor |
US6895991B2 (en) * | 2002-08-09 | 2005-05-24 | Honeywell International, Inc. | Missile thrust system and valve with refractory piston cylinder |
US6951317B2 (en) | 2002-09-03 | 2005-10-04 | Honeywell International Inc. | Vehicle, lightweight pneumatic pilot valve and related systems therefor |
GB0225118D0 (en) * | 2002-10-29 | 2002-12-11 | Honeywell Normalair Garrett | Providing an indication of the position of a valve member |
US20040221896A1 (en) * | 2003-05-08 | 2004-11-11 | Ballenger Devane R. | Position detector for an electro hydraulic servo valve |
US7475607B2 (en) * | 2004-01-08 | 2009-01-13 | Honeywell International Inc. | Sensing apparatus with an integrated gasket on a beam component |
US7273068B2 (en) * | 2004-01-14 | 2007-09-25 | Honeywell International, Inc. | Electric driven, integrated metering and shutoff valve for fluid flow control |
US7093618B2 (en) * | 2004-04-30 | 2006-08-22 | Honeywell International, Inc. | Lounge valve mounting housing and assembly |
JP4496095B2 (en) * | 2005-01-18 | 2010-07-07 | 日本原子力発電株式会社 | Valve open / close detection sensor |
WO2008157298A2 (en) * | 2007-06-15 | 2008-12-24 | Board Of Regents, The University Of Texas System | Thin flexible sensor |
CN101871826A (en) * | 2009-04-22 | 2010-10-27 | 项晓明 | Continuous test device for torsion moment/bending moment of valve and test method thereof |
US8453527B2 (en) * | 2010-03-23 | 2013-06-04 | Baker Hughes Incorporated | Position-sensing device and method |
US20130283762A1 (en) * | 2012-04-27 | 2013-10-31 | General Electric Company | Rotary vane actuator operated air valves |
CA3111311C (en) | 2012-05-25 | 2022-10-18 | Mueller International, Llc | Position indicator for valves |
US20150034183A1 (en) * | 2013-08-01 | 2015-02-05 | General Equipment And Manufacturing Company, Inc., D/B/A Topworx, Inc. | Externally adjustable magnetic target setting |
DE102017115671A1 (en) * | 2017-07-12 | 2019-01-17 | Rolls-Royce Deutschland Ltd & Co Kg | Valve system for a fluid line system in an aircraft engine and method for operating a valve system for a fluid line system in an aircraft engine |
US11619560B2 (en) | 2019-10-18 | 2023-04-04 | Hamilton Sundstrand Corporation | Pressure ripple mitigation in pressure sensors |
EP4001720B1 (en) * | 2020-11-19 | 2023-12-27 | Goodrich Corporation | Valve position indicators |
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GB2139358A (en) * | 1983-05-05 | 1984-11-07 | Standard Telephones Cables Ltd | Piezo-resistive rotation transducer |
DE4228307A1 (en) * | 1992-08-26 | 1994-03-03 | Rexroth Mannesmann Gmbh | Proportional magnetic valve for hydraulic appts. e.g. regulating valve, pump or positioning motor - has strain gauge on leaf spring, one end of which is connected to housing, and other end of which is deflected according to position of control piston |
US5736635A (en) * | 1995-12-22 | 1998-04-07 | Alps Electric Co., Ltd. | Position sensor |
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US3034345A (en) * | 1959-05-19 | 1962-05-15 | Bell Telephone Labor Inc | Gauges using piezoresistive elements |
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US4777979A (en) | 1987-11-16 | 1988-10-18 | Westinghouse Electric Corp. | Position detector for clapper of non-return valve |
DE3838599A1 (en) | 1988-11-15 | 1990-05-17 | Bosch Gmbh Robert | SOLENOID VALVE, ESPECIALLY FOR FUEL INJECTION PUMPS |
US5132583A (en) * | 1989-09-20 | 1992-07-21 | Intevep, S.A. | Piezoresistive material, its preparation and use |
US5048343A (en) | 1990-04-30 | 1991-09-17 | Allied-Signal Inc. | Temperature-compensated strain-gauge amplifier |
DE69111591T2 (en) | 1990-08-31 | 1996-02-29 | Westonbridge Int Ltd | VALVE WITH POSITION DETECTOR AND MICROPUMP WITH IT. |
US5293900A (en) * | 1992-09-30 | 1994-03-15 | Hydro Electronic Devices Inc. (Hed) | Joystick with contactless direct drive device |
US5477149A (en) | 1993-12-29 | 1995-12-19 | Spencer; George M. | Method and apparatus for non-invasive monitoring of solenoid valves |
GB2286871B (en) | 1994-02-16 | 1997-11-05 | Btr Plc | Butterfly valve |
-
1999
- 1999-07-22 US US09/358,773 patent/US6308723B1/en not_active Expired - Lifetime
- 1999-11-18 JP JP2000582766A patent/JP2002530635A/en not_active Withdrawn
- 1999-11-18 EP EP99960489A patent/EP1135666B1/en not_active Expired - Lifetime
- 1999-11-18 ES ES99960489T patent/ES2257091T3/en not_active Expired - Lifetime
- 1999-11-18 WO PCT/US1999/027412 patent/WO2000029812A2/en active IP Right Grant
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2139358A (en) * | 1983-05-05 | 1984-11-07 | Standard Telephones Cables Ltd | Piezo-resistive rotation transducer |
DE4228307A1 (en) * | 1992-08-26 | 1994-03-03 | Rexroth Mannesmann Gmbh | Proportional magnetic valve for hydraulic appts. e.g. regulating valve, pump or positioning motor - has strain gauge on leaf spring, one end of which is connected to housing, and other end of which is deflected according to position of control piston |
US5736635A (en) * | 1995-12-22 | 1998-04-07 | Alps Electric Co., Ltd. | Position sensor |
Non-Patent Citations (1)
Title |
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See also references of EP1135666A2 * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015105872A (en) * | 2013-11-29 | 2015-06-08 | タイコエレクトロニクスジャパン合同会社 | Rotation angle detection sensor and throttle device of internal combustion engine |
JP2015105871A (en) * | 2013-11-29 | 2015-06-08 | タイコエレクトロニクスジャパン合同会社 | Rotation angle detection sensor and throttle device of internal combustion engine |
WO2020016326A1 (en) | 2018-07-18 | 2020-01-23 | Université De Montpellier | Omnidirectional sensor for determining an environmental value of a pivoting object |
FR3084155A1 (en) | 2018-07-18 | 2020-01-24 | Centre National De La Recherche Scientifique | OMNIDIRECTIONAL SENSOR FOR DETERMINING AN ENVIRONMENTAL VALUE OF A PIVOTING OBJECT |
Also Published As
Publication number | Publication date |
---|---|
JP2002530635A (en) | 2002-09-17 |
WO2000029812A3 (en) | 2000-10-05 |
EP1135666A2 (en) | 2001-09-26 |
US6308723B1 (en) | 2001-10-30 |
ES2257091T3 (en) | 2006-07-16 |
EP1135666B1 (en) | 2006-02-22 |
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