Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
  • G01C19/00—Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
  • G01C19/56—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
  • G01C19/5607—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using vibrating tuning forks
  • G01C19/5621—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using vibrating tuning forks the devices involving a micromechanical structure
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
  • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
  • H03H9/24—Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive
  • H03H9/2405—Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive of microelectro-mechanical resonators
  • H03H9/2468—Tuning fork resonators
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
  • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
  • H03H9/24—Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive
  • H03H9/2405—Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive of microelectro-mechanical resonators
  • H03H9/2468—Tuning fork resonators
  • H03H9/2494—H-shaped, i.e. two tuning forks with common base

Definitions

• This invention relates to symmetrical mechanical resonators and in
• classical tuning fork includes two tines connected to a common stem
• piezoelectric crystalline quartz They have also been used as angular
• tines combines with the inertial rotation of the tuning-fork base to induce
• vibration modes in the conventional tuning fork these being:
• the second and fourth modes are parasitic and lead to
• It is a still further object of the invention is to provide a 2-axis rate
• a symmetrical mechanical resonator is
• the said mechanical resonator may be, in particular, a tuning fork
• resonator a frame-type resonator, or any planar resonator.
• coupling means also comprises means for indirectly exciting said movable masses by applying at least one force that acts on said mechanical coupling
• a planar symmetrical mechanical resonator in a further embodiment, is provided.
• inertial angular rare sensor comprises a mechanical resonator
• Fig. 1 illustrates a prior art tuning fork.
• Fig. 2 illustrates an H-type conventional tuning fork.
• Fig. 3 illustrates a conventional frame-type symmetrical resonator.
• Fig. 4 illustrates a tuning fork according to the present invention.
• Fig. 5 illustrates an idealized equivalent of a tuning fork according
• Fig. 6 illustrates an H-type tuning fork according to the present
• Fig. 7 illustrates a frame-type double tuning fork resonator
• Fig. 8 illustrates a frame-type symmetrical resonator according to
• Fig. 9 illustrates another frame-type symmetrical resonator
• Fig. 10 shows a modified flexible element employed in the gyro
• Fig. 11 shows a flexible element as in Fig. 10 but including two
• Fig. 12 illustrates a centrally excited tuning fork according to the
• Fig. 13 illustrates a centrally excited H-type tuning fork according
• Fig. 14 illustrates a centrally excited frame-type symmetrical
• Fig. 15 illustrates a 2-axis rate-sensor according to the present
• Fig. 16 illustrates a modified 2-axis rate-sensor according to the
• Fig. 1 illustrates a conventional, prior art, tuning fork mechanism
• asymmetrical mode is indicated by long arrows.
• Stem 12 is optional and
• the tines may be directly connected to the mounting base.
• Fig. 2 illustrates a two-ended conventional tuning fork, as described
• a mounting structure 16 is common to all the tines.
• Fig. 3 illustrates a frame type, double-tuning fork resonator
• the purpose of the present invention is to provide symmetrical
• Fig. 4 illustrates a tuning fork according to the present
• the tuning fork includes tines 20 and 21, a mounting base 61,
• the purpose of the coupling is to force the two tines to
• apertures portions will be found in the following embodiments as well.
• the two tines 20 and 21 are stiff and are
• the spring 28 represent the equivalent
• Fig. 6 illustrates an H-type tuning fork according to the present
• the respective tines are coupled as before and stems 29 and 30 allow torsional motion of the tuning fork around its line of symmetry.
• Fig. 7 illustrates a frame-type resonator according to the present
• the structure is essentially two tuning forks with their
• 64 and 65 indicate two mounting bases.
• Fig. 8 illustrates another frame-type resonator according to the
• each mechanism comprising bars 34, 35, 36, 37. 66,
• mechamcal couplings 37 are coupled on either side by mechamcal couplings 37 (two altogether), as
• Fig. 9 illustrates a modified frame-type resonator of Fig. 8 where
• Fig. 10 the modified flexible element is employed in the gyro
• the flexible element comprises two flexible elements
• Fig. 12 illustrates an
• the excitation frequency should be one half the
• the electrode set could be of the comb type described in "A
• piezoelectric crystalline sensor is by deflecting element 42 by means of
• Fig. 13 illustrates the application of the above excitation concept to
• Fig. 14 illustrates the application of the above excitation method to
• Fig. 15 illustrates a two-axis vibratory
• rate-sensor including four vibrating
• the four tines are linked with mechamcal couplings 49, 50, 51, and 52,
• Fig. 16 illustrates a modified two-axis angular rate sensor

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• Physics & Mathematics (AREA)
• Acoustics & Sound (AREA)
• Engineering & Computer Science (AREA)
• General Physics & Mathematics (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Gyroscopes (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=11067127

Family Applications (1)

Country Status (4)

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Family Cites Families (2)

• 1995
  • 1995-02-23 IL IL11277095A patent/IL112770A0/xx unknown
• 1996
  • 1996-02-08 WO PCT/US1996/001716 patent/WO1996026445A1/en not_active Application Discontinuation
  • 1996-02-08 EP EP96908464A patent/EP0805984A4/de not_active Withdrawn
  • 1996-02-08 AU AU51697/96A patent/AU5169796A/en not_active Abandoned

Non-Patent Citations (2)

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