IP Library Granted Patent US 12,487,087
Granted Patent B2
US 12,487,087 · App. 18/121,059 · Granted Dec 2, 2025

Gyrocompass

Inventors: Takuya Watanabe (Tokyo, JP); Takashi Koyama (Tokyo, JP); Shota Nishiizumi (Tokyo, JP)
Assignee: Tokyo Keiki Inc.
G01C19/38G01C19/20
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Quick Facts
Patent No.
US 12,487,087
App. No.
18/121,059
Granted
Dec 2, 2025
Kind
B2
Abstract

A gyrocompass includes: a binnacle; a gyro case having a gyro rotor; a vertical ring mounted on the binnacle for rotation about a vertical axis, the vertical axis extending perpendicular to a gimbal axis and a horizontal axis, the gimbal axis extends in a direction of a spin axis of the gyro rotor and the horizontal axis extends perpendicular to the gimbal axis and parallel to a horizontal plane; a horizontal ring supported by the vertical ring for rotation about the gimbal axis and supporting the gyro case for rotation about the horizontal axis or supported by the vertical ring for rotation about the horizontal axis and supporting the gyro case for rotation about the gimbal axis; a horizontal servo motor for rotating the gyro case about the horizontal axis; and an azimuth servo motor mounted on the vertical ring for rotating the vertical ring about the vertical axis.

Claims (32)

1 . A gyrocompass, comprising:

a binnacle adapted to be fixedly mounted on a navigation vehicle;

a gyro case having a gyro rotor contained therein;

a vertical ring mounted on the binnacle for rotation about a vertical axis, the vertical axis extending perpendicular to a gimbal axis and to a horizontal axis, wherein the gimbal axis extends in a direction of a spin axis of the gyro rotor and the horizontal axis extends perpendicular to the gimbal axis and parallel to a horizontal plane;

a horizontal ring which is either (i) supported by the vertical ring for rotation about the gimbal axis and supporting the gyro case for rotation about the horizontal axis or (ii) supported by the vertical ring for rotation about the horizontal axis and supporting the gyro case for rotation about the gimbal axis;

a horizontal-axis-rotation torquer for rotating the gyro case about the horizontal axis; and

a vertical-axis-rotation torquer directly mounted on the vertical ring for rotating the vertical ring about the vertical axis.

2 . The gyrocompass according to claim 1 , wherein:

the horizontal ring is supported by the vertical ring for rotation about the horizontal axis and supporting the gyro case for rotation about the gimbal axis; and

the horizontal-axis-rotation torquer is directly mounted on the vertical ring.

3 . The gyrocompass according to claim 1 , further comprising:

a gyrocompass control system for controlling the horizontal-axis-rotation torquer and the vertical-axis-rotation torquer so as to maintain an orientation of the gyro case; and

a rotary connector comprising a stator mounted on a stationary part of the gyrocompass and a rotor mounted on a rotary part of the gyrocompass, wherein the stationary part comprises the binnacle and the rotary part comprises the gyro case, the vertical ring and the horizontal ring;

wherein the rotary connector provides (i) a first transfer channel for supplying electric power to the gyrocompass control system, the horizontal-axis-rotation torquer and the vertical-axis-rotation torquer and (ii) a second transfer channel which is a communication channel between the gyrocompass control system and an outside of the gyrocompass.

4 . The gyrocompass according to claim 3 , wherein:

the rotary connector comprises a rotary transformer;

the first transfer channel is provided by a first fixed coil mounted on the stator and a first rotatable coil mounted on the rotor; and

the second transfer channel is provided by a second fixed coil mounted on the stator and a second rotatable coil mounted on the rotor.

5 . The gyrocompass according to claim 4 , wherein:

the stator has a groove formed therein, in which the first fixed coil and the second fixed coil are received and mounted one on the other; and

the rotor has a groove formed therein, in which the first rotatable coil and the second rotatable coil are received and mounted one on the other.

6 . The gyrocompass according to claim 2 , further comprising:

a gyrocompass control system for controlling the horizontal-axis-rotation torquer and the vertical-axis-rotation torquer so as to maintain an orientation of the gyro case; and

a rotary connector comprising a stator mounted on a stationary part of the gyrocompass and a rotor mounted on a rotary part of the gyrocompass, wherein the stationary part comprises the binnacle and the rotary part comprises the gyro case, the vertical ring and the horizontal ring;

wherein the rotary connector provides (i) a first transfer channel for supplying electric power to the gyrocompass control system, the horizontal-axis-rotation torquer and the vertical-axis-rotation torquer and (ii) a second transfer channel which is a communication channel between the gyrocompass control system and an outside of the gyrocompass.

7 . The gyrocompass according to claim 6 , wherein:

the rotary connector comprises a rotary transformer;

the first transfer channel is provided by a first fixed coil mounted on the stator and a first rotatable coil mounted on the rotor; and

the second transfer channel is provided by a second fixed coil mounted on the stator and a second rotatable coil mounted on the rotor.

8 . The gyrocompass according to claim 7 , wherein:

the stator has a groove formed therein, in which the first fixed coil and the second fixed coil are received and mounted one on the other; and

the rotor has a groove formed therein, in which the first rotatable coil and the second rotatable coil are received and mounted one on the other.

Assignments (2)
ADDRESS CHANGE Recorded Apr 20, 2026
From: TOKYO KEIKI INC.
To: TOKYO KEIKI INC.
Reel/Frame 075414/0839 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 14, 2023
From: WATANABE, TAKUYA; KOYAMA, TAKASHI; NISHIIZUMI, SHOTA
To: TOKYO KEIKI INC.
Reel/Frame 062971/0254 →
Priority Claims (1)
JP 2022-093869 · Jun 9, 2022 · national
Continuity (1)
Related Publication 20230400304A1 · Dec 14, 2023
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