JPH08159772A - Gyrocompass - Google Patents

Abstract

PURPOSE: To provide a gyrocompass having high accuracy and reliability. CONSTITUTION: A rotary transformer 45 is provided between a rotary part including the gyrocompass 11 and a follow-up ring 15 and a fixed part on the side of a base stage. The rotary transformer 45 has a power supply channel for feeding the power and a signal channel for transmitting and receiving the signals. An azimuth servomotor 29 for rotating the rotary part includes a stator 29-1 having the toroidal three-phase windings and a rotor 29-2 having a permanent magnet. The rotor can be rotated at the intended rotary angle at every 60 deg. by sequentially exciting the secondary winding of the toroidal three-phase windings. Before the gyrocompass 11 is started, a zero-cross mode and a last- azimuth mode are actuated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gyro compass suitable for use in measuring the course of a navigation body such as a ship or an automobile.

[0002]

2. Description of the Related Art As a conventional gyro compass, for example, by the same applicant as the applicant of the present application, 1986 12
There is an example disclosed in Japanese Patent Application No. 60-125867 (Japanese Patent Application Laid-Open No. 61-283813) filed on March 13. Referring to FIGS. 12 and 13, the Japanese Patent Application No. 60-
The example disclosed in No. 125867 will be described.

FIG. 12 shows a front sectional structure of a conventional gyro compass, and FIG. 13 shows a plan structure thereof. As shown, the Z axis is taken in the vertical direction, and the X axis and the Y axis which are orthogonal to each other are taken in the horizontal plane. The gyro compass has a gyro case 111 having a liquid-tight structure, and a gyro rotor (not shown) that rotates at high speed is built in the gyro case 111. Such a gyro case 111 is arranged in a tank 115 filled with a highly viscous fluid such as Dan Pink oil, and is supported by a suspension line 113 extending below the upper end of the tank 115.

As shown in FIG. 13, an annular horizontal ring 11 is provided so as to surround the outside of the tank 115 and be spaced apart from it.
7 are arranged horizontally, and the horizontal ring 117 has horizontal shafts 115A, 115B on both sides in the diametrical direction along the Y-axis direction.
Have. On the other hand, the tank 115 has bearings 119A and 119B on both sides in the diametrical direction along the Y-axis direction.
The 17 horizontal shafts 115A and 115B are fitted to the inner rings of the corresponding bearings 119A and 119B of the tank 115.

The horizontal ring 117 has bearings 123A and 123B on both sides in the diametrical direction along the X-axis direction. Horizontal ring 11
A fork-shaped follower ring 121 is arranged so as to surround the outer side of 7 and is spaced therefrom.
1 is a gimbal shaft 117 on both sides in the diametrical direction along the X-axis direction.
A, 117B. Gimbal axis 11 of follower ring 121
7A and 117B are bearings 123 of the corresponding horizontal ring 117.
It is fitted to the inner rings of A and 123B.

Thus, the tank 115 rotates about the central axis of the horizontal shafts 115A and 115B along the Y-axis direction,
Further, it rotates with the horizontal ring 117 around the central axis of the gimbal shafts 117A and 117B along the X-axis direction.

As shown in FIG. 12, the follow-up ring 121 is mounted on the follow-up shaft 125 in the Z-axis direction. A board 127 is disposed below the gyro compass, and the board 127 has a center hole 127A and a cylindrical protrusion 127B. A bearing 129 having a smaller radius is mounted around the center hole 127A of the board 127, and a bearing 131 having a larger radius is mounted on the upper end of the cylindrical protrusion 127B. The follower shaft 125 is fitted to the inner ring of the inner bearing 129, and the cylindrical wall 121A of the follower ring 121 is fitted to the inner ring of the outer bearing 131.

Thus, the follow-up shaft 125 and the follow-up ring 121.
Is rotatably supported by two bearings 129 and 131.

A horizontal servomotor 141 is mounted on one horizontal shaft 115B of the tank 115. The horizontal servomotor 141 causes the tank 115 to move to the horizontal shaft 115.
It is driven to rotate around A and 115B. The horizontal servomotor 141 is a pancake type direct-acting type that does not use gears and pinions, and is attached to the inner rotor 141A attached to the horizontal shaft 115B of the tank 115 and the horizontal ring 117 corresponding thereto. And an outer stator 141B.

An azimuth servomotor 143 is mounted on the follow-up shaft 125, and the follower ring 121 is driven to rotate around the follow-up shaft 125 by the azimuth servomotor 143.
The azimuth servo motor 143 is a pancake type direct-acting type that does not use gears and pinions, and has an inner rotor 143A attached to the follower shaft 125 and an outer fixed portion attached to the board 127 corresponding thereto. Child 143B.

The follower ring 121 further has a cylindrical skirt portion 121B adjacent to the cylindrical wall 121A, and a slip ring 145 is provided along the skirt portion 121B. Electric power is supplied to the gyro rotor and the horizontal servomotor 141 via the slip ring 145. The slip ring 145 is an inner current collecting ring 145 attached to the skirt portion 121B of the follower ring 121.
A and the outer brush 145B attached to the board 127
And

A mounting portion 135 is mounted on the lower side of the board 127, and an azimuth encoder 147 is mounted in the mounting portion 135. The azimuth angle of the follower ring 121 with respect to the board 127 is detected by the azimuth encoder 147. The azimuth encoder 147 includes an inner shaft portion 147A attached to the coupling 133 attached to the lower end of the follower shaft 125 and an outer stator 147B corresponding to the inner shaft portion 147A attached to the board 127.

The follower shaft 125, the coupling 133 attached thereto, and the shaft portion 147A of the azimuth encoder 147.
And a rotor 143A of the azimuth servomotor 143, and
Follower ring 121 and slip ring 1 attached to it
The 45 collector rings 145A form an integral assembly. The assembly, the horizontal ring 117, and the tank 115 form an integral rotating unit that is rotatable around the center axis of the follow-up shaft 125.

Gyro case 11 for the tank 115
In order to detect the displacement of No. 1, a non-contact displacement detection device is provided. Such non-contact displacement detection devices are installed on both sides of the gyro case 111 along the X-axis direction. The non-contact displacement detection device includes a pair of coils on the equator on the north side and a pair of coils on the south side. Each pair of coils has a primary coil arranged in the gyro case 111 and a secondary coil corresponding to the primary coil mounted on the inner surface of the tank 115.

The tank 115 is equipped with a non-contact displacement detection device.
The amount of movement of the gyro case 111 in the X-axis direction and Y
The angular displacement about the axis and the angular displacement about the Z axis are independently detected. The detected angular displacement around the Y axis is
It is supplied to the horizontal servomotor 141 with or without an amplifier. Horizontal servo motor 14
1 is driven so that the tank 115 becomes the tank 1
It rotates about 15 horizontal axes 115A, and thereby the angular displacement of the tank 115 around the Y axis is controlled to be zero.

Similarly, the detected angular displacement about the Z-axis is supplied to the azimuth servomotor 143 with or without an amplifier. The azimuth servomotor 143 is driven to rotate the follower ring 121 and the horizontal ring 117, and thereby the angular displacement of the tank 115 about the Y axis is controlled to be zero.

In this way, no matter what direction the gyro case 111 is oriented, the suspension system 1 can be operated by such a servo system.
No twist occurs in 13. That is, the gyro is Z
It is not subject to any disturbance torque about its axis, ie about its vertical axis.

The finger pointing action of the gyro will be described with reference to FIG. In FIG. 14, the gyro case 111 is the tank 115.
FIG. 3 is a schematic diagram showing the state of being arranged inside, in which the damping liquid 116 is filled in the tank 115,
The gyro case 111 is suspended by the suspension line 113 while being immersed in the damping liquid 116.

Here, the position of the center of gravity of the gyro case 111 is O ₁ , and the center position of the tank 115 is O ₂ . The connection point between the suspension line 113 and the tank 115 is P, and the connection point between the suspension line 113 and the gyro case 111 is Q. Tank 11
The central axis of 5 passes through the line PO ₂ . Gyro rotor 110
A is the point at which the spin axis of intersects the gyro case 111.
Let B be the points on the tank 115 that correspond to these two points A and B, and are A ′ and B ′. Further, the horizontal plane is H-H '.

When the spin axis of the gyro rotor 110 is horizontal (θ = 0 °), the position O ₁ of the center of gravity of the gyro case 111 coincides with the center position O ₂ of the tank 115.
It is assumed that the spin axis of the gyro rotor 110 is inclined by the inclination angle θ with respect to the horizontal plane H-H '. The finger north end A side of the gyro case 111 is elevated with respect to the horizontal plane.

Since the suspension line 113 has a slight rigidity,
At this time, a bending curve is actually drawn as shown by the broken line. The movement amount ξ (O ₁ −O ₂ ) of the gyro case 111 in the direction along the spin axis with respect to the tank 115 also slightly decreases. However, the suspension line 113 is sufficiently flexible, the change in the amount of movement is small, and the effect is small in a practical design. Therefore, here, description will be made by ignoring such a change in the movement amount.

As described above, by the servo system, the tank 1
15 also inclines so that a straight line passing through the two points A ′ and B ′ on the tank 115 passes through the two points A and B on the gyro case 111. That is, the central axis PO ₂ of the tank 115 is inclined by the inclination angle θ with respect to the vertical line.

If the acceleration does not act from the outside, the force does not act in the spin axis direction of the gyro case 111.
The suspension line 113 coincides with the vertical line. Due to the tension T of the suspension line 113, a moment M about the center of gravity O ₁ of the gyro case 111 is generated. Center of gravity of gyro case 111 O
_If the distance between ₁ and the point Q is r, and the residual weight of the gyro case 111 excluding the buoyancy due to the damper liquid 116 is mg, the moment M is expressed as follows.

[0024]

## EQU1 ## M = Trsin θ = mgr sin θ

The moment M acts as a gyro torque around a horizontal axis (a line passing through the center of gravity O ₁ and perpendicular to the paper surface). In this way, "the torque proportional to the inclination angle of the spin axis with respect to the horizontal plane can be applied around the horizontal axis of the gyro", so that the finger north force is generated and the gyro compass can be obtained. By selecting the distance r, the weight mg, and the angular momentum of the gyro, the finger north movement cycle can be set to several tens of minutes to several hundreds of minutes.

[0026]

A slip ring is used in the conventional gyro compass, and the slip ring has been used to supply power to the gyro rotor and the horizontal servo motor and to transmit and receive a gyro signal.

In the conventional gyro compass, a pancake type direct drive motor is used as the azimuth servo motor. In the direct drive motor, in order to rotate the rotor by 360 °, the stator side is composed of a permanent magnet and the rotor side is composed of an exciting coil, and a slip ring is used as a switching mechanism of the exciting coil.

However, the slip ring is liable to cause a contact failure and has a short life due to mechanical friction.

It is known to use brushless motors to avoid the use of slip rings in azimuth servomotors. In a brushless motor, the stator side is composed of toroidal three-phase windings, and the rotor side is composed of permanent magnets.
The relative positional relationship between the toroidal three-phase winding and the permanent magnet is detected, and predetermined two windings of the three-phase winding are sequentially excited under the control of the commutator control circuit.

The relative positional relationship between the toroidal three-phase winding and the permanent magnet is detected by the azimuth oscillator. As an azimuth oscillator, it is known to use an incremental azimuth encoder with a zero-cross oscillator.

However, the azimuth axis (rotor of the rotary transformer) is increased by the incremental azimuth encoder.
In order to detect the absolute rotation angle of, it is necessary to detect the zero-cross point with a zero-cross oscillator. That is, the relative positional relationship between the toroidal three-phase winding and the permanent magnet could not be detected until after the zero-cross point was detected.

The conventional gyro compass has a drawback that it cannot be in a usable state, that is, in a stationary state, after several hours depending on the direction at the time of starting. For example, if the north end of the gyro finger does not face true north, it may take a considerable amount of time before the north end of the gyro finger faces true north.

In view of the above-mentioned problems, it is an object of the present invention to provide a gyro compass that does not use a slip ring and is more reliable and has a simpler structure.

In view of the above point, the present invention uses an incremental azimuth encoder having a zero-cross oscillator as an azimuth oscillator, and uses a toroidal three-phase winding on the stator side and a permanent rotor on the rotor side as an azimuth servomotor. An object of the present invention is to provide a gyro compass capable of detecting a zero-cross point in a gyro compass using a brushless motor having a magnet.

In view of the above point, the present invention is a gyro compass using an incremental type azimuth encoder, in which the zero crossing is detected and the azimuth at the time of stop is detected when the navigation body is not moving during the restart from the stop. That is, it is an object of the present invention to provide a gyro compass that can be used in a short time by starting from the true north direction.

[0036]

According to the present invention, for example, as shown in FIG. 1, a gyro having a spin axis in the X-axis direction and a support device for rotatably supporting the gyro about the Y-axis and the Z-axis. And a follower ring that supports the support device rotatably around the Y-axis, has a follow-up axis perpendicular to the base, and is rotatable around a vertical axis passing through the follow-up axis, and applies a finger north force to the gyro. In a gyro compass having a pointing device for giving, a rotary transformer is arranged between a rotating part including the gyro and rotatable about the Z-axis and a fixed part including the base. It is characterized by including a signal channel for communicating a signal between the fixed part and the rotary part via a digital serial communication circuit and a power channel for supplying power from the fixed part to the rotary part. To.

According to the present invention, in the gyro compass, the carrier frequency used for the signal channel and the power frequency used for the power channel are different.

According to the present invention, in the gyro compass, the power supply frequency supplied to the rotating portion via the power supply channel is equal to the frequency of the drive power supply for the gyro rotor.

According to the present invention, in the gyro compass, the gyro includes a pickup for detecting rotational displacements of the gyro rotor about the Y axis and the Z axis with respect to the gyro case, and the frequency of the coil exciting power source of the pickup is It is characterized in that it is equal to the excitation frequency of the rotary transformer.

According to the present invention, in the gyro compass, an east-west inclinometer for detecting the rotation angle of the gyro around the X axis and a north-south inclinometer for detecting the rotation angle of the gyro around the Y axis are provided in the rotating portion. The azimuth transmitter for detecting the rotation angle around the Z-axis of the rotating part is attached to the fixed part, and the gyro signal, the east-west inclinometer, the north-south inclinometer, and the above-mentioned inclinometer are attached via the signal channel. It is characterized in that the output signal of the azimuth oscillator is transmitted and received.

According to the present invention, a gyro having a spin axis in the X-axis direction, a supporting device for rotatably supporting the gyro about the Y-axis and the Z-axis, and a supporting device for rotatably supporting the gyro about the Y-axis. A gyro compass having a follower axis perpendicular to the base, and a follower ring rotatable about a vertical axis passing through the follower axis, and a finger north device for applying a finger north force to the gyro. An azimuth servo motor for rotating the rotating portion around the Z axis and an azimuth transmitter for detecting a rotation angle of the rotating portion around the Z axis are mounted below the tracking axis. Including a stator made of toroidal three-phase windings and a rotor made of permanent magnets,
The azimuth transmitter includes a azimuth encoder that incrementally detects the rotation angle of the rotating unit around the Z axis and a zero-cross oscillator. When the gyro compass is activated, the zero-cross mode is activated, and the commutator control circuit is controlled to control the commutator control circuit. Two of the toroidal three-phase windings are sequentially excited to rotate the rotor at an angle of 360 °, and the zero-cross oscillator is configured to generate a zero-cross detection signal. To do.

According to the present invention, in the gyro compass, in the zero-cross mode, the pair of two windings at the position corresponding to the zero-cross oscillator is first excited, and if the zero-cross signal is not generated by the two windings next, One pair of two windings adjacent to each other are excited, and thereby the zero cross can be detected with the minimum number of times of switching of the exciting coil.

According to the present invention, in the gyro compass, the last arm mode is activated when the zero-cross mode ends, whereby the north end of the finger of the gyro is oriented in the true north direction. And

[0044]

According to the gyro compass of the present invention, the flex gyro or TDG 11 is rotatably supported around two axes of the east-west axis, that is, the Y axis and the vertical axis, that is, the Z axis. The structure can be achieved more easily.

A rotary transformer 45, instead of a slip ring, is mounted between the rotating part and the fixed part, which are composed of the flex gyro or TDG 11, the follower ring 15, the north-south inclinometer 21, the east-west inclinometer 23 and the like.

The rotary transformer 45 has at least three channels. A power supply current is supplied from the stationary unit to the rotating unit via the first channel, and signals are transmitted and received between the stationary unit and the rotating unit via the second and third channels.

The azimuth servomotor 29 includes a stator 29-1 made of a toroidal three-phase winding and a rotor 2 made of a permanent magnet.
9-2 is included. First, the predetermined two windings of the three-phase winding are excited, the rotor 29-2 of the azimuth servo motor is rotated to a predetermined position, and further the two windings are sequentially excited to rotate the rotor 29.
By rotating -2 once, the zero-cross point can be detected by the zero-cross mode in which the zero-cross signal is generated without the absolute rotation angle by the azimuth transmitter.

The azimuth servomotor 29 includes a stator 29-1 made of a toroidal three-phase winding and a rotor 2 made of a permanent magnet.
9-2 is included. After detection of the zero-cross signal, the azimuth servo calculation unit 61 calculates the relative positional relationship between the stator 29-1 and the rotor 29-2, and the first two windings of the three-phase windings are excited. To be selected. By further exciting two windings in sequence, the rotor 29 of the azimuth servomotor 29 is
-2 can be freely rotated within a rotation angle of 360 °.

The azimuth transmitter uses an azimuth encoder 31 of the incremental type and has a zero cross. According to the invention, the zero-cross mode is activated, which detects the zero-cross quickly. In the zero-cross mode, first the two windings at the positions corresponding to the zero-cross oscillator are excited,
As a result, when the zero cross is not detected, the next two adjacent windings are excited. Thereby, the zero cross can be detected at the minimum rotation angle and in a short time without rotating the rotor 29-2 of the azimuth servo motor 29 once.

According to the present invention, the zero-cross mode is followed by the last-minute mode. In the last azimuth mode, the follow-up axis, that is, the azimuth axis 17 is forcibly rotated at the time of activation, and the gyro is arranged so that the north end of the finger faces the true north direction. As a result, the gyro can be used in a short time at startup.

[0051]

EXAMPLES Examples of the present invention will be described below with reference to FIGS. FIG. 1 shows a conceptual diagram of a gyro compass according to the present invention. The gyro compass of this example is a flex gyro or a TDG (tuned dry gyr).
o) 11 and such TDG 11 is mounted on the block 13.

As shown in the figure, the XYZ coordinate system fixed to the block 13 is considered, and the Z axis is taken in the vertical direction, and the X axis and the Y axis which are orthogonal to each other are taken in the horizontal plane.

The spin axis of the gyro is arranged along the X-axis, and when the north end of the finger of the gyro is set in the positive direction of the X-axis as shown, the Y-axis is arranged along the east-west direction. The block 13 is supported by a follower ring 15 so as to be rotatable around the Y axis, and the follower ring 15 follows the follower axis 1 along the Z axis.
7, the follower shaft 17 is mounted on the base 10 so as to be rotatable around the Z axis. Thus, block 13 is Y
It is rotatably supported around two axes, the axis and the Z axis.

The block 13 includes a north-south inclinometer or a north-south accelerometer 21 for detecting a tilt in the north-south direction, that is, a rotation tilt θ around the Y-axis, and an east-west inclinometer for detecting a tilt in the east-west direction, that is, a rotation tilt σ around the X-axis, or The east-west accelerometer 23 is attached.

Further, a horizontal servomotor or a horizontal DST (direct servo torquer) 27 is attached along the Y axis of the follower ring 15, and an azimuth servomotor or direction DST (direct servo torquer) is attached along the follower axis 17. ) 2
9 is attached. An azimuth encoder 31 is attached below the tracking shaft 17, and the azimuth encoder 31
The rotation angle of the follow-up shaft 17 around the Z axis is detected by.

The TDG 11 is equipped with a pickup (not shown) for detecting the displacement of the gyro rotor with respect to the gyro case. Such pickup detects the angular displacement of the gyro rotor about the Y axis and the Z axis. Are arranged as follows. A pickup that detects the angular displacement of the gyro rotor about the Y axis is called a horizontal pickup, and a pickup that detects the angular displacement of the gyro rotor about the Z axis is called an azimuth pickup.
In addition, the TDG 11 has a gyro rotor around the Y-axis and Z-axis.
Torque around the axis (not shown) Y Toruca and Z
ToruCa is provided.

When an angular displacement around the vertical axis (Z axis) occurs between the gyro case and the gyro rotor, the angular displacement is detected by the azimuth pickup, and the angular displacement signal is supplied to the azimuth servo computing section 61. It A drive signal is supplied from the azimuth servo calculation unit 61 to the azimuth servo motor 29 via the commutator control circuit 63. As a result, the TDG 11 is rotationally driven around the Z axis, and is controlled so that the angular displacement around the vertical axis (Z axis) between the gyro case and the gyro rotor becomes zero.

Similarly, when an angular displacement around the horizontal axis (Y-axis) occurs between the gyro case and the gyro rotor, the angular displacement is detected by the horizontal pickup, and the angular displacement signal is detected by the horizontal servo calculating section 65. Is supplied to. A drive signal is supplied from the horizontal servo calculator 65 to the horizontal servo motor 27. As a result, the TDG 11 is rotationally driven about the Y axis, and is controlled so that the angular displacement between the gyro case and the gyro rotor about the horizontal axis (Y axis) becomes zero.

Due to this action, no disturbance torque about the horizontal axis (Y axis) and the vertical axis (Z axis) is applied to the gyro.

Next, the finger pointing action of the gyro compass of this example will be described. The finger pointing action of the gyro compass is TD when the mounting surface of the gyro compass is on a horizontal plane.
G11 Y Toluca turns the gyro rotor around the Y axis,
That is, it is obtained by applying a torque Kθ (K is a ballast constant or a finger north constant) around the horizontal axis. However, when the mounting surface of the gyro compass is tilted in the east-west direction, the support mechanism of the gyro compass of this example does not have the east-west system freedom (degree of freedom around the X axis), and should be given to the gyro rotor by the Y torquer. The torque Kθ needs to be divided and applied.

Let T _{Y be} the torqueing signal to torque the gyro rotor around the Y axis by the Y torquer.
A torqueing signal for torqued the gyro rotor about the Z axis by the Z torquer is represented by T _Z. The torqueing signals T _Y and T _Z are represented by the following equation.

[0062]

## EQU2 ## T _Y = Kθ cos σ T _Z = −K θ sin σ

Here, θ is the output signal of the north-south accelerometer 21 (the rise in the south side is +), and σ is the output signal of the east-west accelerometer 23 (the rise in the west is +). K is the Shihoku constant.

The rotation tilt signal θ output from the north-south accelerometer 21 and the rotation tilt signal σ output from the east-west accelerometer 23 are supplied to the compass calculator 35. The compass calculator 35 calculates the torque signals T _Y and T _Z according to the equation (2).
Is calculated. These torqueing signals T _Y and T _Z are passed from the compass calculation unit 35 through the horizontal torqueing circuit 36 and the direction torqueing circuit 37, respectively, and are output from the Y of the TDG 11.
Supplied to Toluca and Z Toluca.

The Y torquer and Z torquer of the TDG 11 torque the gyro rotor about the Y axis, that is, about the horizontal axis. This torqueing amount is “to apply a torque proportional to the inclination of the spin axis with respect to the horizontal plane about the horizontal axis of the gyro”. In this way, a moment equivalent to the moment M shown in the equation of Formula 1 is generated, the finger north force is applied to the gyro case, and the gyro compass is configured.

An example of the gyro compass of the present invention will be described with reference to FIGS. FIG. 2 shows the front structure of the gyro compass of this example, and FIG. 3 shows the plan structure of the gyro compass of this example. The gyrocompass of this example has a board 41 and a cylindrical cover 43 attached to the board 41. In the cover 43, the TDG 11 is in the block 13
The block 13 is supported by a follower ring 15 so as to be rotatable around the Y axis.

As shown in FIG. 2, the block 13 has horizontal axes 13A and 13B on both sides in the east-west direction.
3A and 13B are fitted to the inner rings of the bearings 19A and 19B of the follower ring 15 which are arranged correspondingly. The block 13 includes a north-south inclinometer or north-south accelerometer 2 along the X-axis.
1 is attached. The follower ring 15 has an east-west inclinometer or east-west accelerometer 23 and a horizontal servomotor 27 along the Y-axis.
Is installed.

The horizontal servomotor 27 is shown in FIGS.
It may be a pancake type direct-acting type that does not use gears and pinions similar to the horizontal servomotor 141 described with reference to the inner rotor 27-1 attached to the horizontal shafts 13A and 13B of the block 13. Correspondingly, an outer stator 27-2 attached to the follower ring 15 is included.

A platform 49 is provided below the follower ring 15.
Is mounted on the platform 49, and the azimuth axis, that is, the tracking axis 17, is mounted on the platform 49.

Below the platform 49, a rotary transformer 45, a direction servo motor 29, and a direction encoder 31 are arranged. The rotary transformer 45 has a lower stator 45-1 mounted on the board 41 and an upper rotor 45-2 mounted on the platform 49. According to the present example, by using the rotary transformer 45 instead of the slip ring, the drawbacks of the slip ring are eliminated.

The azimuth servomotor 29 has an outer stator 29-1 mounted on the board 41 and an inner rotor 29-2 mounted on the platform 49. The azimuth encoder 31 may have the same structure as the azimuth encoder 147 described with reference to FIG. 12 and FIG.
Includes an inner shaft portion 31-1 attached to the coupling 47 attached to the lower end portion of and a corresponding outer stator 31-2 attached to the board 41.

Follower ring 15, platform 49, follower shaft 17, rotor 45-2 of rotary transformer 45, rotor 29-1 of direction servomotor 29, and direction encoder 3.
The first shaft portion 31-1 constitutes a rotating portion, and the rotating portion is rotatably supported by the bearing 53A mounted on the platform 49 and the bearing 51 mounted on the follow-up shaft 17.

FIG. 4 shows a structural example of the TDG 11, that is, the flex gyro. Details of the TDG or the flex gyro are, for example, by the same applicant as the applicant of the present application, 1985
Japanese Patent Application No. 60-103083 filed on May 15, 2015
Japanese Patent Application Laid-Open No. 61-260117.

As shown, the XYZ axes of the TDG 11 are taken. Taking the X axis along the spin axis of the gyro rotor,
A Y axis and a Z axis perpendicular to each other are taken. The coordinate system is the X-axis of the XYZ axes taken in block 13 in FIG.
It is aligned with the axes, Y and Z.

The flex gyro includes a housing 151 and an upper cap 1 mounted on the upper side of the housing 151.
53 and a lower cap 155 attached to the lower side. Housing 151 and upper and lower caps 153,
A gyro case is constituted by 155. An upper chamber is formed between the upper surface of the housing 151 and the upper cap 153, and the lower surface of the housing 151 and the lower cap 15 are formed.
A lower chamber is formed between 5.

A gyro rotor 159 is arranged in the upper chamber, and the gyro rotor 159 is elastically supported by a flex hinge 161. A shaft 165 is attached to the flex hinge 161, and the shaft 165 is supported by a center hole of an inner cylindrical protruding portion 151A of the housing 151 via a ball bearing 157.

A motor 167 is arranged in the lower chamber, and the motor 167 has a stator 167-1 and a rotor 167-2 corresponding thereto. The stator 167-1 is mounted on the inner wall of the outer cylindrical protrusion 151B of the housing 151, and the rotor 167-2 is mounted on the lower end of the shaft 165 so as to be surrounded by the stator 167-1.

The gyro rotor 159, the flex hinge 161, the shaft 165, and the rotor 167-2 form an integral assembly, and are configured so that they can rotate at high speed around the central axis of the shaft 165. The central axis of the shaft 165,
That is, the axis of rotation of such an assembly is the spin axis of the gyro rotor.

When an AC voltage is applied to the winding of the motor stator 167-1, the rotating magnetic field generated thereby acts on the rotor 167-2 of the motor. Thereby,
Torque is generated and the rotor 167-2 of the motor is
Rotate with respect to 7-1. Thus, the assemblies 159, 1
61, 165, 167-2 rotate around the X axis, and the gyro rotor 159 rotates at high speed around the spin axis.

The upper chamber is provided with a torquer 171 for applying a torque around the Y axis and the Z axis to the gyro rotor 159. This Toruca 171 corresponds to the Y Toruca and Z Toruca of the TDG 11 described with reference to FIG. Such a torquer 171 includes an annular permanent magnet 171-1 mounted on the gyro rotor 159 and the housing 1 corresponding thereto.
And a Toruca coil 171-2 mounted on the upper surface of 51. The Toruca coil 171-2 is arranged in the annular groove 159A of the gyro rotor 159 and at a distance from the annular groove 159A.

As shown by the arrow in the figure, the permanent magnet 171-1
A magnetic circuit Φ is formed along the annular groove 159A of the gyro rotor 159. By the cooperation of such a magnetic circuit and the magnetic field generated by the Toruca coil 171-2,
Torque is generated.

A pickup 173 is further arranged in the upper chamber. The pickup 173 corresponds to the horizontal pickup and the azimuth pickup of the TDG 11 described with reference to FIG. Pickup 173 is ToruCa 1
It is mounted on the upper surface of the housing 151 adjacent to 71.

Consider a case where the angular velocity about the Y axis or the Z axis orthogonal to the spin axis acts on the housing 151 while the gyro rotor 159 is rotating at a high speed. The gyro rotor retains its position relative to the inertial space by virtue of its orientation retention. Therefore, the gyro rotor 159 is rotationally displaced relative to the housing 151 about the Y axis or the Z axis. The amount of rotational deviation of the gyro rotor 159 around the Y axis or the amount of rotational deviation around the Z axis is detected by the pickup 173.

The configuration and operation of the azimuth servomotor 29 of this embodiment will be described with reference to FIGS. 5, 6 and 9. As shown in FIG. 5A, the azimuth servo motor 29 in this example may be, for example, a direct servo torquer (DST), the outer stator 29-1 includes three pairs of coils, and the inner rotor 29. -2 includes a permanent magnet M. 3 pairs of coils A-D, B
-E and CF are arranged on both sides in the diametrical direction with respect to each other, and the N pole and S pole of the permanent magnet M, that is, both ends are formed to be curved, and a slight gap is provided between the three pairs of coils. Are formed.

FIG. 6 shows three pairs of coils A-D, B-E and C-.
The connection of F is shown. The coils of each pair are connected in series. The same numbers among the numbers attached to the terminals at both ends of each coil are connected, for example, the terminal 2 of the coil A and the terminal 2 of the coil D are connected. 3 connected in series
The pair of coils are connected at one point 0 to form a star shape, as shown in FIG. 6B.

Next, the operation of the azimuth servo motor 29 will be described. As shown in FIG. 5B and FIG. 6B, an exciting current is supplied to two adjacent pairs of coils. Thereby the permanent magnet M
Is applied to the permanent magnet M, and the permanent magnet M is arranged so as to be close to the pair of coils to which the exciting current is not supplied. For example,
When the first and second pairs of coils A-D, B-E are excited, the permanent magnet M is placed close to the third coil C-F, that is, between the coils C and F. It

The region of the couple generated at this time is ± 90 °, and the rotor 29-2 cannot be rotated up to 360 ° by such couple. However, as shown in FIG. 5B, the rotor 29-2 can be freely rotated within 360 ° by sequentially supplying the exciting current to the two adjacent coils.

As shown in FIGS. 1 and 9, the azimuth servo calculator 61 receives the output signal of the azimuth encoder 31 and calculates the azimuth angle φ of the azimuth axis 17. Thereby, the relative position of the rotor 29-2 with respect to the stator 29-1 is determined, and the three pairs of coils A-D, B- of the azimuth servomotor 29 are determined.
Two pairs of coils are selected from E and C-F. The command signal is supplied to the azimuth servomotor 29 via the mutator control circuit 63. The two pairs of coils selected thereby are excited, the couple acts on the permanent magnet M, and the rotor 29-2 rotates.

Next, referring to FIG. 7, the rotary transformer 4
The configuration and operation of No. 5 will be described. Rotary transformer 45
Has an upper rotor 45-1 and a lower stator 45-2. As shown, the rotor 45-1 and the stator 45-
An electric signal is transmitted by the magnetic circuit MF generated between the two. The rotary transformer 45 of this example has three channels as shown. Outer first channel C
H1 is for power supply, the second channel CH2 is for bidirectional serial communication by digital signals, and the inner third channel CH3 is for transmission of the output signal of the azimuth pickup.

The signals transmitted and received via the rotary transformer 45 and the control loop will be described with reference to FIGS. 8 and 9. FIG. 8 shows a rotor 45 of the rotary transformer 45-
1 shows the control circuit arranged on the first side, and FIG. 9 shows the control circuit arranged on the stator 45-2 side of the rotary transformer 45.

First, a signal transmitted / received via the first channel CH1 will be described. A power supply circuit 82 is arranged on the stator 45-2 side of the rotary transformer 45,
The AC power source from the power source circuit 82 is supplied to the rectifier circuit 81 on the rotor 45-1 side via the first channel CH1. The DC power source obtained by the rectifier circuit 81 is used as a power source for the horizontal servo motor 29, a power source for driving the gyro rotor of the TDG 11, a power source for the north-south accelerometer 21 and the east-west accelerometer 23, and a power source for a control circuit.

An AC power supply is used for the gyro rotor, azimuth pickup, and horizontal pickup of the TDG 11, but by using the AC power supply frequency from the power supply circuit 82 as the gyro rotor power supply frequency and the pickup excitation frequency, the platform 49 is used. It is not necessary to provide a power supply for the gyro rotor and a power supply for pickup excitation on the top.

Next, a signal transmitted / received via the second channel CH2 will be described. Rotary transformer 45
Azimuth servo calculator 6 arranged on the stator 45-2 side of the
The azimuth angle φ of the navigation vehicle is calculated by 1. The azimuth signal φ, the speed signal V of the navigation vehicle, and the latitude signal λ are supplied to the digital serial communication circuit 77 on the stator 45-2 side via the interface unit 78.

Such a signal is further supplied from the digital serial communication circuit 77 to the digital serial communication circuit 75 on the rotor 45-1 side via the second channel CH2 of the rotary transformer 45. The digital signal supplied from the digital serial communication circuit 75 is supplied to the compass calculator 35. By making the frequency for digital serial communication about 2 to 100 times the frequency for power supply, the power supply circuit 82 and the digital serial communication circuit 7
Interference between 7 is avoided.

On the other hand, the output signals of the two accelerometers 21 and 23 are supplied to the AD converter 72, converted into digital signals, and supplied to the compass calculator 35. As described above, the compass calculation unit 35 calculates the equation (2). The torqueing signals T _Y and T _Z obtained thereby are supplied to the torquer circuits 36 and 37.

Finally, a signal transmitted / received via the third channel CH3 will be described. The output signals of the horizontal pickup and the azimuth pickup mounted on the TDG 11 are converted into digital signals by the AD converter 71.
The horizontal pickup digital signal is used by the horizontal servo calculation unit 6
It is supplied to the horizontal servo motor 29 via 5. On the other hand, the azimuth pickup digital signal is supplied to the digital serial communication circuit 74, and the third channel CH
3 is supplied to the digital serial communication circuit 76 on the stator 45-2 side of the gyro rotor. The azimuth pickup digital signal is supplied from the digital serial communication circuit 76 to the azimuth servo calculation unit 61.

On the other hand, the azimuth servo calculation unit 61 inputs the rotation angle signal LSB output from the azimuth encoder 31 to calculate the absolute rotation angle, that is, the azimuth angle φ, and supplies it as a gyro signal to the outside. Incidentally, the direction servo calculation unit 61
Is output to the azimuth servomotor 29 via the commutator control circuit 63.

According to this example, as shown in FIG. 8, on the rotor 45-1 side of the gyro rotor, the rectifying circuit 81, the torqueing circuits 36 and 37, the compass calculating section 35, the horizontal servo calculating section 65, and the AD converting circuit are provided. 71 and 72 and digital serial communication circuits 74 and 75 are arranged, and these may be mounted on the platform 49, for example.

Further, as shown in FIG. 9, the power supply circuit 82 arranged on the stator 45-2 side of the gyro rotor, the digital serial communication circuits 76 and 77, the interface section 78, the azimuth servo operation section 61, and the commutator control circuit. 63 and the like may be attached to the board 41, for example.

The operation of the gyro compass of the present invention will be described with reference to FIG. The gyro compass of this example is operated in three modes: a zero-cross mode, a last storm mode, and a compass mode. The startup sequence unit 62 is inserted on the input side of the commutator control circuit 63. The start-up sequence unit 62 has a zero-cross mode unit 62-1, a last-minute mode 62-2, and a compass mode 62-3. Direction servo calculation unit 61
Output is input to any of these three mode parts depending on the operation mode.

According to the present invention, the zero cross mode and the last arm mode are activated before the gyro compass is actually activated. Direction encoder 3 in zero-cross mode
Used by 1 to detect zero crossings. The azimuth encoder 31 is configured to incrementally detect the rotation angle of the azimuth axis, that is, the follow-up axis 17. The detection of the rotation angle is counted after detecting the origin, that is, the zero cross attached to the predetermined angular position.

The zero-cross mode will be described with reference to FIGS. 5A and 5B again. As described above, of the three pairs of coils A-D, B-E, and C-F of the azimuth servo motor 29, two adjacent pairs of coils, for example, the first and second pairs of coils A-D and B. When a current i ₁ is applied to −E, the permanent magnet M receives a couple due to the magnetic field generated by the coil, and rotates to the position of the coil in which no current flows, that is, the third pair of coils C-F and stops. To do. That is, the N pole and S of the permanent magnet M
The poles each stop in front of the third pair of coils CF.

Therefore, if the electric current is made to flow through the predetermined two pairs of coils in advance, the permanent magnet M is always arranged at the position of the other pair of coils. If no zero cross is detected thereby, then the next two pairs of adjacent coils, ie
A current i _{2 is} passed through the second and third pairs of coils BE and CF. As a result, the permanent magnet M receives a couple of forces, rotates to the position of the first pair of coils A to D, and stops. In this way, the permanent magnet M rotates every 60 ° by sequentially switching the exciting coil. Thereby, the zero cross is detected.

Even if the azimuth angle of the follow-up axis 17, that is, the absolute angle is unknown, the azimuth servo motor 2 is operated by this series of operations.
The zero cross can be detected by rotating the rotor 29-2 of 9 every 60 °.

FIG. 11 shows the zero-cross mode for detecting the zero-cross with the minimum number of times of exciter coil switching. The zero cross point is set between the predetermined two pairs of coils S1 and S3. For example, as shown in FIG. 5A, a zero cross point Z is set between the first pair of coils A-D and the third pair of coils C-F. First, when the zero-cross mode is started in step 100, a current is passed through the predetermined two pairs of coils S1 and S2 to excite them. For example, a current is passed through the first and second pairs of coils A-D and B-E. The permanent magnet M is arranged close to the coil S3 in which no current flows, that is, the third pair of coils C-F. In step 101, it is determined whether or not the zero cross is detected.

Since there is a zero-cross point Z between the two pairs of coils S1 and S3, normally, a zero-cross is detected in step 101 and the process ends in step 105. If no zero cross is detected in step 101,
Proceeding to step 103, the next two pairs of coils S2, S3,
That is, the second and third pairs of coils B-E and C-F are excited. As a result, the permanent magnet M rotates 60 °, and the coil S1 in which no current flows, that is, the first pair of coils A
Located close to -D. As a result, the zero cross is detected, and the process ends in step 105.

When the zero cross is still not detected, the process returns to step 101. Normally, a zero cross is detected in two steps 101 and 103. Thus
By setting the zero-cross point at a predetermined position, the zero-cross can be detected in the shortest number of times of switching and in a short time.

The function of the zero-cross mode unit 62-1 in the activation sequence unit 62 will be described with reference to FIG. 10 again. In the zero-cross mode, the rotational angular velocity of the azimuth servo motor 29 is controlled so that the follow-up shaft 17 rotates at the desired rotational angular velocity dφ _Z / dt. First, the desired rotation angular velocity signal dφ _Z / dt is zero cross mode unit 62.
-1 is supplied. The zero-cross mode unit 62-1 supplies the current value signal to the commutator control circuit 63. Such current value signals are supplied to two predetermined pairs of coils of the azimuth servo motor 29.

As a result, the rotor 29-2 of the azimuth servo motor 29 and the follow-up shaft 17 rotate, and the rotation angle is detected by the azimuth encoder 31, and the rotation angle signal LSB is detected.
Is supplied to the azimuth servo calculation unit 61. The azimuth servo calculation unit 61 inputs the rotation angle signal LSB and supplies it to the zero cross mode unit 62-1.

The zero-cross mode unit 62-1 calculates the number of LSBs per unit time, and thereby calculates the actual rotational angular velocity dφ _Z / dt of the tracking shaft 17. The zero-cross mode unit 62-1 determines the actual rotation angular velocity signal dφ _Z.
/ Dt and the desired rotational angular velocity signal dφ _Z / dt are compared,
A current value signal corresponding to the deviation between the two is calculated, and the calculated current value signal is passed through the commutator control circuit 63 to the azimuth servo motor 29.
Give feedback to. As a result, the follow-up shaft 17 rotates at the desired rotation angular velocity dφ _Z / dt.

At the same time, the zero-cross mode unit 62-1 is set to L
The SB numbers are integrated to calculate the actual rotation angle φ _i of the follower shaft 17. The rotation angle φ _i is supplied to the last armature mode unit 62-2 after the zero cross mode ends.

Thus, in the zero-cross mode of this example,
The azimuth servo motor 29 causes the follow-up shaft 17 to rotate at a desired rotation angular velocity dφ _Z / dt, so that the zero cross can be detected.

Next, the last-minute mode of this example will be described. According to the present invention, the last storm mode is used after the end of the zero cross mode and before starting the operation in the compass mode. In a gyrocompass of the type in which the rotation angle around the azimuth axis is detected by a zero-cross oscillator and an incremental encoder, when a zero-cross is detected by the zero-cross mode, the stopping azimuth is always mechanically constant. When the compass mode is operated in such a state, it takes time for the north end of the finger of the gyro compass to face north.

According to the last armature mode of this embodiment, the finger north end of the gyro compass is oriented in the true north direction in advance before operating the compass mode. As a result, the compass mode can be started with the north end of the finger of the gyro compass facing the true north direction.

When the gyro compass is stopped and then restarted, it is assumed that the navigation body is not moving during that time.
Therefore, when the zero-cross mode is started, the finger north end of the gyro compass faces the true north. From such a state,
When the zero cross is detected by the zero cross mode, the follow-up shaft 17 rotates by a predetermined rotation angle φ _i . The last armature mode of this example is configured to detect the rotation angle φ _i of the follow-up shaft 17 in the zero-cross mode, and after detecting the zero-cross, rotate the follow-up shaft 17 in the opposite direction by the rotation angle φ _i .

The function of the last-minute mode 62-2 in the startup sequence will be described with reference to FIG.
When the follow-up shaft 17 rotates by the rotation angle φ _{i in} the zero cross mode, the zero cross mode unit 62-1 supplies the rotation angle signal φ _i to the last armature mode unit 62-2. The lasting azimuth mode unit 62-2 supplies a current value signal to the commutator control circuit 63 in order to rotate the follower shaft 17 in the opposite direction by the rotation angle φ _i . Such current value signals are supplied to two predetermined pairs of coils of the azimuth servo motor 29.

As a result, the rotor 29-2 of the azimuth servo motor 29 and the follow-up shaft 17 are rotated, and the rotation angle is detected by the azimuth encoder 31 and supplied to the azimuth servo calculator 61 as the rotation angle signal LSB. The azimuth servo calculation unit 61 inputs the rotation angle signal LSB, calculates the absolute rotation angle of the follow-up shaft 17, that is, the azimuth angle, and supplies it to the last azimuth mode unit 62-2.

The last armature mode unit 62-2 calculates a current value signal to be supplied to the azimuth servomotor 29 from the azimuth angle and feeds it back to the azimuth servomotor 29 via the commutator control circuit 63. As a result, the follow-up shaft 17 rotates by the rotation angle φ _i . In this way, when the gyro compass mode is started, the finger north end of the gyro compass faces the true north.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and it will be understood by those skilled in the art that various other configurations can be adopted without departing from the gist of the present invention. Easy to understand.

[0120]

According to the present invention, since the rotary transformer 45 is used instead of the conventional slip ring, there is no contact failure and friction due to mechanical contact unlike the slip ring, and the reliability is high. There is an advantage that a gyro compass can be supplied.

According to the present invention, the azimuth servomotor is composed of toroidal three-phase windings, and by controlling the commutator control circuit, two windings of the toroidal three-phase windings are sequentially excited to rotate the rotor by 360 °. Since it can be rotated by the angle within, there is an advantage that the zero-cross detection signal can be generated by the zero-cross oscillator in the zero-cross mode when the gyro compass is activated.

According to the present invention, in the zero cross mode,
First, a pair of two windings at a position corresponding to the zero-cross oscillator is excited, and when a zero-cross signal is not generated, the next pair of adjacent two windings is excited. Therefore, there is an advantage that the zero cross can be detected with the minimum number of switching of the exciting coil.

According to the present invention, when the zero cross mode is finished, the last azimuth mode is activated, whereby the finger north end of the gyro is directed to the true north direction. There is an advantage that the compass mode can be started in the state of being aimed at.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a gyro compass according to the present invention.

FIG. 2 is a sectional view showing a front structure of an example of a gyro compass according to the present invention.

FIG. 3 is a cross-sectional view showing a planar configuration of an example of a gyro compass according to the present invention.

FIG. 4 is a cross-sectional view of an example TDG.

FIG. 5 is an explanatory diagram for explaining the operation of the azimuth servomotor used for the gyro compass according to the present invention.

FIG. 6 is an explanatory diagram illustrating connection of coils of the azimuth servo motor used in the gyro compass according to the present invention.

FIG. 7 is an explanatory diagram illustrating an example of a rotary transformer used in the gyro compass according to the present invention.

FIG. 8 is an explanatory diagram illustrating a rotor-side circuit of a rotary transformer.

FIG. 9 is an explanatory diagram illustrating a stator side circuit of a rotary transformer.

FIG. 10 is an explanatory diagram illustrating an example of a startup sequence of a gyro compass according to the present invention.

FIG. 11 is a flowchart illustrating a process of a zero cross mode according to the present invention.

FIG. 12 is a front sectional view of an example of a conventional gyro compass.

FIG. 13 is a plan sectional view of an example of a conventional gyro compass.

FIG. 14 is a diagram showing an outline of the inside of a conventional TDG tank.

[Explanation of symbols]

 10 base 11 TGD 13 block 13A, 13A 'horizontal axis 15 follower ring 17 follower axis 19 bearing 21 north-south inclinometer or north-south accelerometer 23 east-west inclinometer or east-west accelerometer 27 horizontal servomotor 27-1 rotor 27-2 fixed Child 29 Direction servo motor 31 Direction encoder 35 Compass calculation unit 36 Horizontal torqueing circuit 37 Direction torqueing circuit 41 Board device 43 Cover 45 Rotary transformer 47 Coupling 49 Platform 51, 53A Bearing 61 Direction servo calculation unit 62 Start sequence unit 63 Commutator control circuit 65 Horizontal Servo Calculation Unit 110 Gyro Rotor 111 Gyro Case 113 Suspended Wire 115 Tank 115A, 115B Horizontal Axis 116 Liquid 117 Horizontal Ring 117A, 117B Gimbal Axis 119A, 11 9B bearing 121 follower ring 121A cylindrical wall 121B skirt part 123A, 123B bearing 125 follower shaft 127 follower plate 127A center shaft 127B protrusion 129, 131 bearing 133 coupling 135 mounting part 141 horizontal servomotor 141A rotor 141B stator Motor 143A Rotor 143B Stator 145 Slip ring 145A Current collector ring 145B Brush 147 Direction encoder 151 Housing 153 Upper cap 155 Lower cap 157 Ball bearing 159 Gyro rotor 161 Flex hinge 161A Center hole 161-1 Ginval 161-2 Boss 161-2 -3 Outer peripheral ring 161-4 Inner hinge part 161-5 Outer hinge part 165 Shaft 167 Motor 167-1 Stator 167-2 Rotation 171-1 permanent magnet 171-2 Torukakoiru 173 pickup

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuichi Fujimoto 2-16-46 Minami Kamata, Ota-ku, Tokyo Within Tokimec Co., Ltd.

Claims (8)

[Claims] 1. A gyro having a spin axis in the X-axis direction, a support device for rotatably supporting the gyro about the Y-axis and the Z-axis, and a support for rotatably supporting the support device about the Y-axis. In a gyro compass having a follow-up ring having a follow-up axis perpendicular to, and a follow-up ring rotatable about a vertical axis passing through the follow-up axis, and a finger north device for applying a finger north force to the gyro, A rotary transformer is disposed between a rotating part that can rotate about the Z axis and a fixed part that includes the base, and the rotary transformer outputs a signal between the fixed part and the rotating part via a digital serial communication circuit. A gyro compass, comprising: a signal channel for communicating with the rotary unit and a power channel for supplying power from the fixed unit to the rotating unit. 2. The gyrocompass according to claim 1, wherein a carrier frequency used for the signal channel and a power supply frequency used for the power supply channel are different from each other. 3. The gyrocompass according to claim 1 or 2, wherein the power supply frequency supplied to the rotating portion via the power supply channel is equal to the frequency of the drive power supply of the gyrorotor. . 4. The gyro compass according to claim 1, 2 or 3, wherein the gyro includes a pickup for detecting rotational displacements of a gyro rotor with respect to a gyro case about a Y axis and a Z axis, and a coil excitation of the pickup. A gyro compass characterized in that the frequency of the power source is equal to the excitation frequency of the rotary transformer. 5. The gyro compass according to claim 1, 2, 3 or 4, wherein the rotating portion includes an east-west inclinometer for detecting a rotation angle of the gyro about the X axis and a rotation angle of the gyro about the Y axis. The north-south inclinometer that detects the rotation angle is attached to the fixed part, and the azimuth transmitter that detects the rotation angle around the Z-axis of the rotating part is attached to the fixed part. The gyro signal via the signal channel and the east-west inclinometer are installed. A gyro compass characterized in that the output signals of the north-south inclinometer and the azimuth transmitter are transmitted and received. 6. A gyro having a spin axis in the X-axis direction, a support device for rotatably supporting the gyro about the Y-axis and the Z-axis, and a support base for rotatably supporting the support device about the Y-axis. A follower ring having a follower axis perpendicular to the follower axis and rotatable about a vertical axis passing through the follower axis, and a finger north device for applying a finger north force to the gyro. An azimuth servomotor for rotating the rotating portion around the Z axis and an azimuth transmitter for detecting a rotation angle of the rotating portion around the Z axis are mounted on the lower side of the azimuth servomotor. The azimuth transmitter includes a stator made of wires and a rotor made of a permanent magnet, and the azimuth transmitter includes a azimuth encoder for incrementally detecting a rotation angle of the rotating portion around the Z axis and a zero cross transmitter. The zero-cross mode is activated at the time of starting, and by controlling the commutator control circuit, two windings of the toroidal three-phase windings are sequentially excited to rotate the rotor at an angle within 360 °, and the zero-crossing is performed. A gyrocompass, wherein the oscillator is configured to generate a zero-cross detection signal. 7. The gyrocompass according to claim 6, wherein, in the zero-cross mode, first, a pair of two windings at a position corresponding to the zero-cross oscillator is excited, and when the zero-cross signal is not generated, the A gyro compass characterized in that a pair of two windings adjacent to is excited so that a zero cross can be detected with a minimum number of times of switching of the exciting coil. 8. The gyro compass according to claim 6 or 7, wherein when the zero cross mode ends, the last azimuth mode is activated, whereby the north end of the finger of the gyro is directed in the true north direction. A gyro compass characterized by that.