GB2162314A - Transducer - Google Patents

Transducer Download PDF

Info

Publication number
GB2162314A
GB2162314A GB8518730A GB8518730A GB2162314A GB 2162314 A GB2162314 A GB 2162314A GB 8518730 A GB8518730 A GB 8518730A GB 8518730 A GB8518730 A GB 8518730A GB 2162314 A GB2162314 A GB 2162314A
Authority
GB
United Kingdom
Prior art keywords
filaments
transducer
support
base
tuning fork
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.)
Granted
Application number
GB8518730A
Other versions
GB2162314B (en
GB8518730D0 (en
Inventor
J C Greenwood
D Wilson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Original Assignee
STC PLC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by STC PLC filed Critical STC PLC
Publication of GB8518730D0 publication Critical patent/GB8518730D0/en
Publication of GB2162314A publication Critical patent/GB2162314A/en
Application granted granted Critical
Publication of GB2162314B publication Critical patent/GB2162314B/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/18Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration in two or more dimensions
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00Measuring force or stress, in general
    • G01L1/16Measuring force or stress, in general using properties of piezoelectric devices
    • G01L1/162Measuring force or stress, in general using properties of piezoelectric devices using piezoelectric resonators
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00Measuring force or stress, in general
    • G01L1/18Measuring force or stress, in general using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
    • G01L1/183Measuring force or stress, in general using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material by measuring variations of frequency of vibrating piezo-resistive material
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/0802Details
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/097Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by vibratory elements
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P2015/0805Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration
    • G01P2015/0822Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration for defining out-of-plane movement of the mass
    • G01P2015/0825Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration for defining out-of-plane movement of the mass for one single degree of freedom of movement of the mass
    • G01P2015/0828Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration for defining out-of-plane movement of the mass for one single degree of freedom of movement of the mass the mass being of the paddle type being suspended at one of its longitudinal ends

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Gyroscopes (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)

Abstract

A transducer for stress or strain measurement comprises a pair of parallel stretched silicon filaments 12 which vibrate in antiphase in their common plane. The resonant vibrational frequency is determined by the external forces applied to the filaments. The transducer may be employed as a sensor element in an inertial guidance system. The filaments form a double-ended tuning fork structure attached at its roots 13, 14 to a single crystal silicon support 11 having flexible regions 15 by which external forces are applied to the filaments. Piezoelectric layers or electrostrictive pn junctions at the roots 13, 14 establish filament vibration which may then be detected electrically or optically. <IMAGE>

Description

SPECIFICATION Transducer This invention relates to transducers for use e.g. as stress gauges for measuring stress or strain and in particular to such a transducer in which the responsive element is a mechanical resonator.
According to the invention there is provided a transducer responsive to a force applied thereto, the transducer including a single crystal silicon support structure, and a pair of parallel silicon filaments forming a double ended tuning fork structure and coupled to the support via the two base or root portions of the tuning fork, means disposed on the base or root portions for vibrating the filaments in antiphase and in their common plane, and means whereby a force applied to the support is transmitted to the filaments thereby determining their resonant frequency.
As the filaments vibrate in antiphase in a common plane the structure is dynamically balanced and is thus relatively insensitive to spurious resonances introduced via the mounting of the device. The structure may be used in a variety of applications but is of particular use as an accelerometer in an inertial guidance system.
An embodiment of the invention will now be described with reference to the accompanying drawing in which: Figure 1 is a three quarters view of the transducer; Figure 2 is a plan view of the transducer, Figure 3 is a sectional view in the plane x-x of Fig. 2, and Figure 4 is a schematic diagram of an inertial guidance system employing transducers of the type shown in Figs. 1, 2 and 3.
Referring to the drawings, the transducer comprises a support frame structure 11 of single crystal silicon across which a parallel pair of silicon filaments 12 are stretched. The filaments are formed as a double ended tuning fork structure supported via its base or root portions 13, 14 on the frame 11. In this way the filaments 1 2 are substantially isolated from the support.
The support structure 11 is provided with two relatively thin portions 1 5 whereby the structure may be flexed to apply a tension force to the filaments 1 2 thereby determining their resonant vibrational frequency.
In use the filaments vibrate in antiphase and in a mode confined to their common plane. This ensures that the structure is dynamically balanced.
Excitation of the resonator filaments may be achieved by shock excitation or by a positive feedback arrangement, the drive force being applied via the base or root portions 13, 14.
Typically the base portions 13, 14 of the structure are doped to provide electrostrictive regions 1 6. A pn junction is provided between each portion 13, 14 and the supporting frame 11. An electric field applied across this junction such that the junction is reverse biassed produces a stress that is proportional to the square of the electric field. Application of an oscillating field, with a suitable steady voltage bias, causes corresponding changes of tension in the filaments 1 2 driving them into resonance in antiphase. Alternatively excitation of the filaments may be provided via a piezoelectric layer (not shown) deposited on the base portion. Typically such a layer comprises zinc oxide or barium titanate.The drive force is applied to the filaments via the base or root portions such that the arrangement. is compressed or stretched so that the filaments are driven into an antiphase vibrational mode in their common plane. As the filaments are substantially decoupled from the frame 11 by the base portions 13, 14, and as the drive is applied directly to the filaments and not via the frame 11, the arrangement has a high Q factor.
Oscillation of the filaments may be detected electrically, or optically via an optical fibre directed at one filament. Light transmitted along the fibre is reflected from the filament and modulated with the resonant frequency.
In some applications the filaments 1 2 may be driven into and/or maintained in oscillation by an optical drive signal via photovoltaic devices (not shown) disposed on the base portions 13, 1 4. An optical feedback system may be used to maintain oscillation. Such a technique is described in out UK specification No. 2,121,953 (J.C. Greenwood 42).
The structure may be formed by selective etching from a body of single crystal silicon, the device configuration being defined by boron doping or by the use of an electrolytic etch stop. Typically the filaments are defined by doping with boron to a level of about 4 X 10'9 atoms/cc. The silicon body is then masked and exposed to a selective etch comprising a mixture of catechol, ethylene diamine and water, or potassium hydroxide and isopropyl alcohol. Such techniques are more fully described in our published specification No. 1,211,496 (J.C. Greenwood-6).
The transducer has particular application as an accelerometer. For this purpose the frame 11 is mounted via one end portion 1 1a (Fig.
1) on a support (not shown), the free portion of the frame providing an inertial mass. Movement of the free portion of the frame about the thin portions 1 5 in response to an acceleration causes corresponding tension or compression of the filaments 1 2. Fig. 4 shows a schematic diagram of an inertial guidance system, e.g. for use in a vehicle. Accelerations in the X, Y and Z directions are sensed by corresponding transducers 41, 42 and 43.
The outputs of these transducers are fed via respective X, Y and Z amplifiers (44 to 46) to a central control unit 47. In response to the input signals received from the amplifiers, and to preset course information, the control unit provides output signals to X, Y and Z guidance controls (48-50) whereby a desired course may be maintained.

Claims (8)

1. A transducer responsive to a force applied thereto, the transducer including a single crystal silicon support structure, and a pair of parallel silicon filaments forming a double ended tuning fork structure and coupled to the support via the two base or root portions of the tuning fork, means disposed on the base or root portions for vibrating the filaments in antiphase and in their common plane, and means whereby a force applied to the support is transmitted to the filaments thereby determining their resonant frequency.
2. A transducer as claimed in claim 1, wherein said support structure has a flexible portion whereby a force may be transmitted to the filaments by distortion of the support.
3. A transducer as claimed in claim 1 or 2, wherein electrostrictive means are provided whereby the filaments, in use, are maintained in oscillation.
4. A transducer as claimed in claim 1 or 2, wherein piezoelectric means are provided whereby the filaments, in use, are maintained in oscillation.
5. A transducer as claimed in claim 4, wherein said piezoelectric means comprise a layer of zinc oxide or barium titanate deposited on each said base portion.
6. A transducer substantially as described herein with reference to Figs. 1 to 3 of the accompanying drawings.
7. An inertial guidance system incorporating one or more transducers as claimed in any one of claims 1 to 6.
8. A vehicle provided with a guidance system as claimed in claim 7.
GB8518730A 1984-07-25 1985-07-24 Transducer Expired GB2162314B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB848418914A GB8418914D0 (en) 1984-07-25 1984-07-25 Transducer

Publications (3)

Publication Number Publication Date
GB8518730D0 GB8518730D0 (en) 1985-08-29
GB2162314A true GB2162314A (en) 1986-01-29
GB2162314B GB2162314B (en) 1987-12-16

Family

ID=10564413

Family Applications (2)

Application Number Title Priority Date Filing Date
GB848418914A Pending GB8418914D0 (en) 1984-07-25 1984-07-25 Transducer
GB8518730A Expired GB2162314B (en) 1984-07-25 1985-07-24 Transducer

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB848418914A Pending GB8418914D0 (en) 1984-07-25 1984-07-25 Transducer

Country Status (1)

Country Link
GB (2) GB8418914D0 (en)

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2185106A (en) * 1985-12-13 1987-07-08 Gen Electric Co Plc An optically-driven vibrating sensor
EP0244086A2 (en) * 1986-04-26 1987-11-04 Stc Plc Resonator device
GB2197069A (en) * 1986-11-03 1988-05-11 Stc Plc Optically driven sensor device
GB2201776A (en) * 1987-01-24 1988-09-07 Schlumberger Electronics Resonantly vibratable sensors
FR2627592A1 (en) * 1988-02-22 1989-08-25 Sagem PENDULUM ACCELEROMETER NOT SERVED WITH RESONANT BEAM
US4912990A (en) * 1989-02-27 1990-04-03 Sundstrand Data Control, Inc. Magnetically driven vibrating beam force transducer
US4945765A (en) * 1988-08-31 1990-08-07 Kearfott Guidance & Navigation Corp. Silicon micromachined accelerometer
EP0419596A1 (en) * 1989-02-27 1991-04-03 Sundstrand Data Control Accelerometer with coplanar push-pull force transducers.
US5060526A (en) * 1989-05-30 1991-10-29 Schlumberger Industries, Inc. Laminated semiconductor sensor with vibrating element
US5165279A (en) * 1989-07-06 1992-11-24 Sundstrand Corporation Monolithic accelerometer with flexurally mounted force transducer
US5170665A (en) * 1989-08-08 1992-12-15 Denis Janiaud Accelerometric sensor with flectional vibratory beams
GB2303450A (en) * 1993-08-03 1997-02-19 Univ Brunel DETF load cell
EP0762132A2 (en) * 1995-08-24 1997-03-12 Murata Manufacturing Co., Ltd. Acceleration sensor
EP0855583A2 (en) * 1996-10-31 1998-07-29 Consorzio ABB per lo Sviluppo Tecnologico Device for measuring a pressure
WO1998053328A1 (en) * 1997-05-23 1998-11-26 Sextant Avionique Micro-accelerometer with capacitive resonator
US5962786A (en) * 1995-09-26 1999-10-05 Onera (Office National D'eudes Et De Recheres Aerospatiales) Monolithic accelerometric transducer
JP2008209388A (en) * 2006-10-13 2008-09-11 Seiko Epson Corp Acceleration sensor
JP2008309731A (en) * 2007-06-18 2008-12-25 Epson Toyocom Corp Acceleration detection unit and acceleration sensor
US7565840B2 (en) * 2005-12-13 2009-07-28 Epson Toyocom Corporation Acceleration sensor element and acceleration sensor
EP2607906A1 (en) * 2011-12-20 2013-06-26 Honeywell International Inc. Double-ended tuning fork with outrigger excitation
JP2015025796A (en) * 2013-06-21 2015-02-05 国立大学法人名古屋大学 Load sensor with quartz crystal resonator
RU2569409C1 (en) * 2014-09-10 2015-11-27 Открытое акционерное общество "Научно-исследовательский институт физических измерений" Tuning-fork measuring transformer of mechanical stresses and deformations
GB2556040A (en) * 2016-11-10 2018-05-23 Geometric Design Ltd Vibrating-element force transducer
US9998089B2 (en) 2012-12-14 2018-06-12 General Electric Company Resonator device
RU2726723C1 (en) * 2019-12-24 2020-07-15 Федеральное государственное бюджетное образовательное учреждение высшего образования "Астраханский государственный технический университет" ФГБОУ ВО "АГТУ" Device for measuring drilling mud pressure in well
RU2737901C1 (en) * 2020-01-27 2020-12-04 Федеральное государственное бюджетное образовательное учреждение высшего образования "Астраханский государственный технический университет" ФГБОУ ВО "АГТУ" Method of drilling fluid pressure measurement in well

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4215570A (en) * 1979-04-20 1980-08-05 The United States Of America As Represented By The United States Department Of Energy Miniature quartz resonator force transducer
US4299122A (en) * 1978-10-11 1981-11-10 Yokogawa Electric Works, Ltd. Force transducer
EP0050307A2 (en) * 1980-10-20 1982-04-28 Quartex, Inc. Resonator force transducer
EP0052318A1 (en) * 1980-11-17 1982-05-26 Quartex, Inc. Force transducer
EP0060185A1 (en) * 1981-03-04 1982-09-15 The Bendix Corporation Vibrating beam rotation sensor
GB2115551A (en) * 1982-02-09 1983-09-07 Itt Ind Ltd Load sensor
GB2121953A (en) * 1982-06-10 1984-01-04 Itt Ind Ltd Improvements in transducers

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4299122A (en) * 1978-10-11 1981-11-10 Yokogawa Electric Works, Ltd. Force transducer
US4215570A (en) * 1979-04-20 1980-08-05 The United States Of America As Represented By The United States Department Of Energy Miniature quartz resonator force transducer
EP0050307A2 (en) * 1980-10-20 1982-04-28 Quartex, Inc. Resonator force transducer
EP0052318A1 (en) * 1980-11-17 1982-05-26 Quartex, Inc. Force transducer
EP0060185A1 (en) * 1981-03-04 1982-09-15 The Bendix Corporation Vibrating beam rotation sensor
GB2115551A (en) * 1982-02-09 1983-09-07 Itt Ind Ltd Load sensor
GB2121953A (en) * 1982-06-10 1984-01-04 Itt Ind Ltd Improvements in transducers

Cited By (41)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2185106A (en) * 1985-12-13 1987-07-08 Gen Electric Co Plc An optically-driven vibrating sensor
GB2185106B (en) * 1985-12-13 1990-04-25 Gen Electric Plc A sensor
EP0244086A3 (en) * 1986-04-26 1989-07-19 Stc Plc Resonator device resonator device
EP0244086A2 (en) * 1986-04-26 1987-11-04 Stc Plc Resonator device
US4813271A (en) * 1986-04-26 1989-03-21 Stc Plc Resonator device
GB2197069B (en) * 1986-11-03 1990-10-24 Stc Plc Sensor device
GB2197069A (en) * 1986-11-03 1988-05-11 Stc Plc Optically driven sensor device
GB2201776A (en) * 1987-01-24 1988-09-07 Schlumberger Electronics Resonantly vibratable sensors
FR2627592A1 (en) * 1988-02-22 1989-08-25 Sagem PENDULUM ACCELEROMETER NOT SERVED WITH RESONANT BEAM
EP0331557A1 (en) * 1988-02-22 1989-09-06 Societe D'applications Generales D'electricite Et De Mecanique Sagem Non-assisted pendulum accelerometer with a resonating beam
US4939935A (en) * 1988-02-22 1990-07-10 Societe D'applications Generales D'electricite Et De Mecanique Pendular non-servoed tuning beam accelerometer
US4945765A (en) * 1988-08-31 1990-08-07 Kearfott Guidance & Navigation Corp. Silicon micromachined accelerometer
US4912990A (en) * 1989-02-27 1990-04-03 Sundstrand Data Control, Inc. Magnetically driven vibrating beam force transducer
EP0419596A1 (en) * 1989-02-27 1991-04-03 Sundstrand Data Control Accelerometer with coplanar push-pull force transducers.
EP0419596A4 (en) * 1989-02-27 1991-07-24 Sundstrand Data Control, Inc. Accelerometer with coplanar push-pull force transducers
US5060526A (en) * 1989-05-30 1991-10-29 Schlumberger Industries, Inc. Laminated semiconductor sensor with vibrating element
US5165279A (en) * 1989-07-06 1992-11-24 Sundstrand Corporation Monolithic accelerometer with flexurally mounted force transducer
US5170665A (en) * 1989-08-08 1992-12-15 Denis Janiaud Accelerometric sensor with flectional vibratory beams
GB2303450B (en) * 1993-08-03 1997-07-09 Univ Brunel Detf load cell
GB2303450A (en) * 1993-08-03 1997-02-19 Univ Brunel DETF load cell
EP0762132A3 (en) * 1995-08-24 1998-04-15 Murata Manufacturing Co., Ltd. Acceleration sensor
EP0762132A2 (en) * 1995-08-24 1997-03-12 Murata Manufacturing Co., Ltd. Acceleration sensor
US5962786A (en) * 1995-09-26 1999-10-05 Onera (Office National D'eudes Et De Recheres Aerospatiales) Monolithic accelerometric transducer
EP0855583A2 (en) * 1996-10-31 1998-07-29 Consorzio ABB per lo Sviluppo Tecnologico Device for measuring a pressure
EP0855583A3 (en) * 1996-10-31 1999-03-24 Consorzio ABB per lo Sviluppo Tecnologico Device for measuring a pressure
US5969257A (en) * 1996-10-31 1999-10-19 Consorzio Abb Per Lo Sviluppo Tecnologico Pressure measuring membrane with resonant element vibrating orthogonal to membrane movement
WO1998053328A1 (en) * 1997-05-23 1998-11-26 Sextant Avionique Micro-accelerometer with capacitive resonator
FR2763694A1 (en) * 1997-05-23 1998-11-27 Sextant Avionique CAPACITIVE RESONATOR MICRO-ACCELEROMETER
US6311556B1 (en) 1997-05-23 2001-11-06 Sextant Avionique Micro-accelerometer with capacitive resonator
US7565840B2 (en) * 2005-12-13 2009-07-28 Epson Toyocom Corporation Acceleration sensor element and acceleration sensor
JP2008209388A (en) * 2006-10-13 2008-09-11 Seiko Epson Corp Acceleration sensor
JP2008309731A (en) * 2007-06-18 2008-12-25 Epson Toyocom Corp Acceleration detection unit and acceleration sensor
EP2607906A1 (en) * 2011-12-20 2013-06-26 Honeywell International Inc. Double-ended tuning fork with outrigger excitation
JP2013130567A (en) * 2011-12-20 2013-07-04 Honeywell Internatl Inc Double-ended tuning fork with outrigger excitation
US8887567B2 (en) 2011-12-20 2014-11-18 Honeywell International Inc. Double-ended tuning fork with outrigger excitation
US9998089B2 (en) 2012-12-14 2018-06-12 General Electric Company Resonator device
JP2015025796A (en) * 2013-06-21 2015-02-05 国立大学法人名古屋大学 Load sensor with quartz crystal resonator
RU2569409C1 (en) * 2014-09-10 2015-11-27 Открытое акционерное общество "Научно-исследовательский институт физических измерений" Tuning-fork measuring transformer of mechanical stresses and deformations
GB2556040A (en) * 2016-11-10 2018-05-23 Geometric Design Ltd Vibrating-element force transducer
RU2726723C1 (en) * 2019-12-24 2020-07-15 Федеральное государственное бюджетное образовательное учреждение высшего образования "Астраханский государственный технический университет" ФГБОУ ВО "АГТУ" Device for measuring drilling mud pressure in well
RU2737901C1 (en) * 2020-01-27 2020-12-04 Федеральное государственное бюджетное образовательное учреждение высшего образования "Астраханский государственный технический университет" ФГБОУ ВО "АГТУ" Method of drilling fluid pressure measurement in well

Also Published As

Publication number Publication date
GB2162314B (en) 1987-12-16
GB8518730D0 (en) 1985-08-29
GB8418914D0 (en) 1984-08-30

Similar Documents

Publication Publication Date Title
GB2162314A (en) Transducer
US4813271A (en) Resonator device
US4567451A (en) Resonator having optical feedback coupling
US4901586A (en) Electrostatically driven dual vibrating beam force transducer
US7605391B2 (en) Optically coupled resonator
US4381672A (en) Vibrating beam rotation sensor
US6745627B1 (en) Electrostatic drive for accelerometer
US7379629B1 (en) Optically coupled resonant pressure sensor
EP1376087B1 (en) High temperature resonant integrated microstructure sensor
GB2186688A (en) Vibrating beam or string force transducer with single isolator springs
US5537872A (en) Angular rate sensor
US6453744B2 (en) Low radiation capture cross-section electrode material for prompt radiation environments
US4264838A (en) Force balanced piezoelectric vibratory rate sensor
US4503715A (en) Load sensors
US3431808A (en) Torsion-operated oscillators
US4706259A (en) Mounting and isolation system for tuning fork temperature sensor
EP1166129A1 (en) Vibrating beam force sensor
GB2215053A (en) Electro-mechanical oscillating transducer devices
CA1201903A (en) Load sensors
JP3129022B2 (en) Acceleration sensor
Langdon Micromachining of Silicon for Sensors
GB2215052A (en) Resonantly vibrating temperature sensor
JPH03238330A (en) Optical type vibration force sensor

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee