Tokimec Inc.

Kabushikikaisha Tokyo Keiki

Tokyo Keiki Company Limited

K.k. Tokyo Keiki

Kabushiki Kaisha Tokyo Keikio

Takeshi Hojo

Michio Fukano

Shinichi Kawada

Takafumi Nakaishi

Kanshi Yamamoto

Takao Murakoshi

Kazuteru Sato

Shigeru Nakamura

Isao Masuzawa

Shin-ichi Kawada

Kazushige Murabayashi

Mamoru Akimoto

Fuyuki Hane

Mikio Morohoshi

Kazuaki Tani

Yoshinori Kamiya

Koichi Umeno

Masashi Konno

Mitsuru Katoh

Fuyuki Hame

Mutumi Takahashi

Kazuya Arai

Mitsuru Kato

Yasuke Kosai

Akihiro Cho

Toru Maeda

Yoshiyuki Okada

Naoki Sakuraoka

Youji Okamura

Shin-Ichi Kawada

Masahiko Saito

Noboru Itakura

Takashi Saijo

To provide a gyro compass for the use of a high speed ship, in a gyro compass of the type having north-seeking means which is applied to support a gyro sphere or gyro case immersed in a liquid in a tank, a substantially first-order lag filter is provided in an azimuth follow-up loop or a damping loop, the substantially first-order lag filter having a time constant T.sub.F which is approximately equal to a ratio C/k.sub.T of the viscosity torque coefficient C to the twisting torque coefficient k.sub.T of the torque produced between the tank and the gyro case. A speed error correcting means has a substantially first-order lag filter having a time constant which is approximately equal to that of the north-seeking means, and is applied to correct the output of azimuth indicator by a speed error correcting angle through the substantially first-order lag filter.

Gyro compass

An anti-rolling apparatus according to the present invention includes rail members which are formed in straight form and disposed perpendicular to a rolling axis of an object whose rolling is to be reduced, a movable weight capable of reciprocating along the rail members, and two springs for generating a stability force for the movable weight, wherein the two springs are elongated or contracted alternately when the movable weight is reciprocated.

Anti-rolling apparatus

An electrostatic supporting type acceleration detecting gyro apparatus is formed as an active type so as to be able to positively cancel a displacement of a gyro rotor. Control DC voltages for generating electrostatic supporting forces and displacement detection AC voltages for detecting a displacement of gyro rotor are applied to electrostatic supporting electrodes, and mechanism control circuits detect displacement indicating voltage signals (P.sub.1A) through (P.sub.4B). A displacement of the gyro rotor and the control DC voltages applied to the electrostatic supporting electrodes are computed based on the displacement detection voltages (P.sub.1A) through (P.sub.4B) outputted from the mechanism control circuits.

Acceleration-detecting type gyro and manufacturing method thereof

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 acceleration detection gyro apparatus is of the electrostatic supporting type. This gyro apparatus call be made inexpensive, long in life, excellent in durability and can be applied to a wide variety of fields. A gyro rotor (20) is supported relative to a gyro case (21) by an electrostatic supporting force in a non-contact fashion and rotated about the spin axis along the Z axis by a rotor driving system. The gyro rotor (20) is disk-shaped and constructed by forming metal thin film electrodes on both surfaces of a plate member made of preferably an insulating material. The gyro apparatus includes a slave control system for slaving a displacement of the gyro rotor (20) relative to the gyro case (21) in the Z-axis direction (spin axis direction) and a central position control system for slaving a displacement of the gyro rotor (20) in the X-axis and Y-axon directions.

Method of making a gyro apparatus

A fiber optic gyro can overcome the defects encountered with conventional fiber optic gyros of phase-modulation method, closed-loop system with serrodyne modulation and digital modulation. A reference phase difference .DELTA..beta. and a ramp phase difference .sigma. are generated in an interference light intensity signal I by use of a triangular waveform, i.e., delta serrodyne waveform signal. The reference phase difference .DELTA..beta. is changed to constant values .DELTA..beta..sub.A and .DELTA..beta..sub.B whose absolute values are the same and whose signs are different at every times T.sub.A and T.sub.B. A phase x of the interference light intensity signal I becomes equal to x=.DELTA..theta.+.sigma.+.DELTA..beta.. The ramp phase difference .sigma. is controlled so as to satisfy .DELTA..theta.+.sigma.=0. Accordingly, at the stable point of the control loop, a Sagnac phase difference .DELTA..theta. is equal to the ramp phase difference .sigma.. Further, a phase x of the interference light intensity signal I does not contain the Sagnac phase difference .DELTA..theta., and hence x=.DELTA..beta.. Also, a fiber optic gyro can eliminate a bias, in particular, optically-generated bias. In a fiber optic gyro of phase-modulation method or delta serrodyne system, a phase controller is supplied with a phase control voltage signal V.sub.S of period T and a square wave signal V.sub.2 of period T for correcting an optical bias caused by an amplitude modulation generated by the phase control voltage signal V.sub.S in the added form. The square wave signal V.sub.2 has a constant magnitude H and is inverted in polarity at points in which the phase control voltage signal V.sub.S is maximized or minimized. The magnitude H and the polarity of the square wave signal V.sub.2 are selected such that an optical bias is minimized.

Closed loop type fiber optic gyroscope for measuring absolute rotation

An acceleration detection gyro apparatus is of the electrostatic supporting type. This gyro apparatus can be made inexpensive, long in life, excellent in durability and can be applied to a wide variety of fields. A gyro rotor (20) is supported relative to a gyro case (21) by an electrostatic supporting force in a non-contact fashion and rotated about the spin axis along the Z axis by a rotor driving system. The gyro rotor (20) is disk-shaped and constructed by forming metal thin film electrodes on both surfaces of a plate member made of preferably an insulating material. The gyro apparatus includes a slave control system for slaving a displacement of the gyro rotor (20) relative to the gyro case (21) in the Z-axis direction (spin axis direction) and a central position control system for slaving a displacement of the gyro rotor (20) in the X-axis and Y-axis directions.

Electrostatic rate gyroscope

Acceleration-detection type gyro

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 gyro compass having a gyro case housing therein a gyro and supported with freedom of three axes, functions for outputting a signal corresponding to an inclined angle of the gyro spin axis relative to the horizontal plane, and a function for applying a torque around a vertical axis of the gyro case in proportion to an input signal. A controller is supplied with a signal corresponding to the inclined angle and a latitude value at which the gyro compass is located, and a constant relative to the input latitude value is determined by the controller after the gyro compass is energized. A signal, resulting from differentiating the signal corresponding to the inclined angle during a predetermined time, is added to the product of the signal corresponding to the inclined angle and the constant. This added signal functions as the input signal for the gyro, whereby a constant optimum north-seeking movement is carried out regardless of the change of the latitude value. An error corrector is provided having supplied to it the signal corresponding to the inclined angle, the speed signal of the vehicle and its heading azimuth signal, and a bias error caused by the inclined angle of the gyro compass spin axis and an azimuth error caused by the movement of the vehicle are estimated and calculated to thereby reduce an azimuth error caused by any bias error and the vehicles' movement.

A gyro compass having a gyro case housing therein a gyro and supported with freedom of three axes, functions for outputting a signal corresponding to an inclined angle of the gyro spin axis relative to the horizontal plane and a function for applying a torque around a vertical axis of the gyro case in proportion to an input signal, and a controller supplied with the signal corresponding to the inclined angle and a latitude value at which the gyro compass is located, wherein a constant relative to the input latitude value is set by the controller after the gyro compass is energized, a signal, which results from differentiating the signal corresponding to the inclined angle during a predetermined time, is added to a signal, which results from multiplying the signal corresponding to the inclined angle with the constant and an added result is set as the input signal, whereby a constant optimum north-seeking movement is carried out regardless of the change of the latitude value to thereby reduce a settle time. Also, the gyro compass having an error corrector supplied with the signal corresponding to the inclined angle, a speed signal of a navigation vehicle and its heading azimuth signal, wherein a bias error caused by the inclined angle of the gyro compass spin axis and an azimuth error caused by the movement of the navigation vehicle are estimated and calculated to thereby reduce an azimuth error caused by the bias error.

A gyro compass having a gyro case housing therein a gyro whose spin axis is held substantially in the horizontal plane, a supporting device for supporting the gyro case with freedom of three axes and means for applying a torque proportional to an inclined angle of the gyro spin axis relative to the horizontal plane around a vertical axis of the gyro case perpendicular to the spin axis is disclosed in which there are provided a detecting device for detecting an inclination angle of the spin axis relative to said horizontal plane, torquer for applying a torque to the gyro case about its vertical axis, and an acceleration error controlling device for receiving an output signal from the detecting means and for controlling the torquer such that the torquer produces a predetermined torque to be applied to the gyro case about its vertical axis.

A force generating apparatus having spacings through which magnetic fluxes are traveled, a magnetic circuit including two permanent magnets supplying magnetic fluxes to the spacings and a conductor disposed in the direction perpendicular to the magnetic fluxes in the spacings is comprised of two pair of permanent magnets of the same size, and a member for disposing the two pair of permanent magnets such that magnetic axes thereof are opposed in parallel to each other, wherein a total sum of magnetic moments caused by the two pair of permanent magnets is cancelled out. Therefore, the force generating apparatus can be prevented from producing a harmful torque even if an external magnetic field acts thereon.

Force generating apparatus

A pair of torquer magnets each comprising a cup-shaped yoke is provided with a disk-like permanent magnet and a pole piece. A through-hole provided through the center of the torquer magnet and a spool member made of a magnetic compensating metal is inserted into and fixed in the through-hole. The spool is shaped to have a central portion intermediate its end of a substantially smaller diameter.

Thermally stabilized accelerometer

A gyro compass having a gyro case incorporating a gyro of which the spin axis is substantially horizontal, a vertical ring disposed around the outer periphery of the gyro case and for rotatably supporting the gyro case around a vertical axis, a follow-up pickup for detecting an angular displacement between the gyro case and the vertical ring around the vertical axis, an accelerometer having an input axis parallel to the spin axis, a vertical torquer mounted on the vertical ring for applying a torque of magnitude proportional to an input signal to the gyro case around the vertical axis, and a control apparatus for receiving an output signal of the accelerometer and for supplying its output to the vertical torquer, in which during a predetermined time after the gyro compass is started to operate, the output signal from the accelerometer is differentiated to produce a differentiation signal which is then supplied to the vertical torquer to reduce a settling time of the north-seeking action.

Growing community of inventors

Kuroiso, Japan

Takeshi Hojo