Tokimec Inc.

Kabushikikaisha Tokyo Keiki

Kazuteru Sato

Takeshi Hojo

Kanshi Yamamoto

Michio Fukano

Noriyuki Akaba

Takao Murakoshi

Shigeru Nakamura

Yoshinori Kamiya

Shin-ichi Kawada

Fuyuki Hane

Mikio Morohoshi

Masashi Konno

Atsushi Kawakami

Koichi Umeno

Youji Okamura

Masahiko Saito

Takashi Saijo

Mutumi Takahashi

Kazuya Arai

Yasuke Kosai

Akihiro Cho

This invention relates to a vibration-type gyro apparatus for measuring an angular velocity using the Coriolis force exerted on a tuning fork. The tuning fork has two vibrational members symmetric about a Z axis. The two vibrational members vibrate along Z axis and are displaced along a Y axis by the Coriolis force. Each of the two vibrational members includes a cantilevered tabular member arranged along an XZ plane and has a shape symmetric about the center axis thereof. Electrode sections are formed on the two sides of the vibrational members, and electrodes are formed in the internal space of a casing at positions corresponding to the electrode sections. The electrodes are arranged by being deviated outward or inward of the center axis of the vibration members with respect to the electrode sections. Each of the electrodes is supplied with a displacement detection AC voltage and a control voltage from a detection and drive circuit.

Vibration-type gyro apparatus for calculating angular velocity

An antenna having a central axis is supported on a supporting member which in turn is supported on an azimuth gimbal. The antenna and the supporting member are rotatable around an elevation axis perpendicular to the central axis gimbal is supported on a base and is rotatable around an azimuth axis perpendicular to the elevation axis. A first gyro having an input axis parallel to the elevation axis is secured to the supporting member, and a second gyro having an input axis perpendicular to both the central axis and the elevation angle axis is secured to the supporting member. An accelerometer is provided for outputting a signal representative of an inclination angle of the central axis relative to a horizontal plane. An azimuth transmitter is provided for outputting a signal representative of a rotation angle of the azimuth gimbal around the azimuth axis. The difference between a signal corresponding to the altitude angle of the satellite and the signal of the accelerometer is fed to the torquer of the first gyro, while the output signal of the azimuth transmitter and the signals corresponding to the ship's heading azimuth and a satellite azimuth angle are fed to a torquer of the second gyro to thereby direct the central axis of the antenna to the satellite.

Antenna directing apparatus

A navigation apparatus utilizing a global positioning system having at least first and second satellite reception antennas installed on a navigation vehicle with a predetermined distance therebetween, a first azimuth computing unit for computing a first azimuth angle of the navigation vehicle from satellite radio waves received at the first and second antennas and a phase difference therebetween, a second azimuth computing unit for computing a second azimuth angle from a time change of antenna positions calculated from the satellite radio wave received at the first or second reception antenna, first and second multiplying units for multiplying outputs of the first and second azimuth computing units with predetermined coefficients respectively, an adding unit for adding outputs of the first and second multiplying units to produce a third azimuth angle, and a coefficient control unit for varying coefficient values of the first and second multiplying units in accordance with either the satellite arrangement or turning frequency of the navigation vehicle.

Navigation apparatus using a global positioning system

A gyro apparatus having a tuning fork and a detecting portion for detecting the moment generated by Coriolis force in the tuning fork is disclosed, in which the detecting portion is formed of a rectangular-shaped hinge, a base portion to which both ends of the rectangular-shaped hinge are fixed and a pair of detection piezo-electric elements fixed to the rectangular-shaped hinge spaced apart from each other in its up and down direction and in which the tuning fork is fixed to the central portion of the rectangular-shaped hinge between the pair of detection piezo-electric elements such that the tuning fork axis becomes substantially perpendicular to the longitudinal direction of the rectangular-shaped hinge portion and parallel to the plane of the rectangular-shaped hinge and the center of mass of the tuning fork coincides with the center of the rectangular-shaped hinge.

Gyro apparatus

A vibration-type gyro apparatus is disclosed, which includes a vibration mass portion, a piezo-electric element for detecting the displacement of the apparatus and a preamplifier having an input resistance R and supplied with the output from the piezo-electric element, wherein the input resistance R is selected to have a value substantially expressed as R.apprxeq.1/C.omega. (where C is an electrostatic capacity of the piezo-electric element and .omega. is a vibration angular velocity of the mass portion) so that the gyro apparatus will be substantially free of variations due to temperature changes.

Vibration-type gyro apparatus

A gyro apparatus is disclosed which includes a base table, a detecting piezoelectric element attached at its one end to the base table such that its longitudinal direction, is perpendicular to the surface of the base table, a tuning fork having a vibration surface parallel to the surface of the base table and disposed such that its axis is parallel to the surface of the detecting piezoelectric element, and an L-shaped attaching portion attached to a base portion of the tuning fork such that its one leg portion is parallel to said surface of the base table and extended in the direction to vibration mass portions of the tuning fork, wherein the one leg portion is attached with the other end of the detecting piezoelectric element.

Growing community of inventors

Tokyo, Japan

Kazuteru Sato