JPH0763227B2 - Gyro rotor drive - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gyro rotor driving device that drives a gyro rotor, and more particularly to a gyro rotor driving device that smoothly raises the rotation of the gyro rotor from startup to synchronous rotation.

<Prior Art> A gyro rotor has a peculiar structure in which the rotor part is arranged outside the stator part for the purpose of increasing the moment of inertia compared to the total weight, but the principle is a general induction motor. There is no difference with. However, in the induction motor drive device, which is the premise of the present invention, a relatively large capacitor is connected to a specific phase at the time of startup, and when the rotation increases to some extent, the centrifugal force switch attached to the rotor portion switches to a smaller capacitor for synchronization. It is supposed to have a structure that rotates. On the other hand, the gyro rotor, on the other hand, is the same in that the condenser is switched and synchronized rotation is performed, but since it rotates at a high speed of 24000 rpm, a very slight (a few mg) imbalance in weight balance causes a very large vibration, which causes centrifugal force. There is a structural difference from the induction motor described above in that the force switch is not used.

Hereinafter, description will be given with reference to the drawings.

FIG. 2 is a schematic configuration diagram of a gyro compass, and FIG. 3 is a diagram for explaining a conventional technique.

In FIG. 2 and FIG. 3, the roller ball 11 containing the gyro rotor 15 has a conductive support liquid 14 so as not to come into contact with the liquid tank 8.
Float on. The power source E is composed of a slip ring 13, an upper counter electrode 8a, and a lower counter electrode 8b via a supporting liquid 14 and a rolling ball 11
Supplied internally. The roller ball 11 is supported by the repulsive force of the magnetic field generated by the repulsion wheel 11c in the support liquid 14 whose temperature is kept constant by temperature control in advance, the weight thereof is adjusted so as to slightly sink. While the wheel ball 11 is facing north and is stationary, the power source E and the follow-up electrodes 8d, 8 of the liquid tank 8 are held.
Bridge resistances 12a and 12b between e and the follower electrode 8 of the liquid tank 8
A Wheatstone bridge circuit is constituted by the supporting liquid resistance F _R between d and 8e and the strip electrode 11d of the ball 11. With this Wheatstone bridge circuit, the deviation of the relative position between the roller ball 11 and the liquid tank 8 is detected as an error voltage e _E , and the servo amplifier 10
Then, the servo motor 5 is driven, and the liquid tank 8 is rotated by following the wheel ball 11 through the gear mechanism 3. In this way, the direction of the vessel is continuously displayed on the compass card 2 and the pointer 1, and the azimuth signal OU is output from the synchro 4.

The inner gimbal ring 9 and the outer gimbal ring 6 are intended to always support the liquid tank 8 almost horizontally with respect to the box body 7 that moves in association with the motion of the ship, and the slip ring 13 is used for the liquid tank. The wire is not twisted when turning 8.

By the way, the driving device for driving the gyro rotor in the roller ball 11 is expensive in the two-phase and three-phase power sources, and because of the structural limitation of the roller ball support system, the electrodes cannot be provided at three locations. The reason is as follows.

Gyro rotor 15 (M is a motor) condenser (C ₁ ...
A circuit that inserts a small power resistance R ₁ into a phase that does not pass through C ₃ ) and extracts a voltage proportional to the flowing current, rectifies and smoothes it, and activates relay RL ₁ is connected, and a capacitor (C ₁ … C
_A circuit for switching the combined capacitance of the capacitors (C ₁ ... C ₃ ) by connecting the two-way three-terminal thyristor T ₁ with the contacts of the relay RL ₁ is connected to the phase passing through ₃ ).

That is, while the rotation speed of the gyro rotor 15 is low, the power resistance R ₁
The value of the current flowing through is large (relay RL ₁ is on, the combined capacitance of the capacitors is large), and the power resistance R ₁ increases as the rotation speed increases.
The value of the current flowing in (relay RL ₁ is off, the combined capacitance of the capacitors is small), and the gyro rotor 15 reaches synchronous rotation.

<Problems to be Solved by the Invention> However, in the configuration of this gyro rotor, the value of the current flowing through the power resistance R ₁ changes under the influence of the change in the supporting liquid resistance F _R. Also, the relay RL ₁ may be repeatedly turned on and off, and the rotation of the gyro rotor may not increase. That is, this is the case when the relay RL ₁ is turned off when the increase in rotation is not sufficient.
At this time, since the gyro rotor is driven with a small capacity even though the rotation increase is not sufficient, a larger current flows through the power resistance R ₁ than when the gyro rotor is driven with a large capacity, and the relay RL ₁ is restarted. It is turned on, and this is repeated thereafter. There are problems such as.

The present invention has been made in view of the above circumstances, and directly obtains the rotation speed of the gyro rotor by a rotation detection element, and smoothly increases the rotation of the gyro rotor from startup to synchronous rotation. An object of the present invention is to provide a gyro rotor driving device capable of performing the above.

<Means for Solving the Problems> In order to achieve such an object, the present invention reduces the capacity of the capacitor with an increase in the rotation speed of the gyro rotor, and smoothes the rotation of the gyro rotor until the synchronous rotation. In a gyro rotor driving device that raises to, directly detecting the rotation of the rotor portion of the gyro rotor,
The rotation detection element that outputs a pulse signal corresponding to the number of rotations, and the pulse signal of this rotation detection element counts, outputs an output signal when a certain number is counted, and resets the count by an input reset signal. A first counter, a reference oscillator that outputs a reference pulse signal having a period corresponding to a reference rotation speed that changes the capacitance of the capacitor, and the pulse signal of the reference oscillator is counted to count a fixed number. When the output signal is output at the same time, the count is reset by the input reset signal.
And a capacitance change circuit that reduces the capacitance of the capacitor when the count of the first counter ends earlier than the count of the second counter based on the output signals of the first counter and the second counter. Is provided, and the output signal of the counter on the side that has finished counting earlier resets the other counting counter, controls the capacitance change circuit, and follows the speed change counted by the first counter. The feature is that the rotation of the gyro rotor is smoothly increased.

<Embodiment> An embodiment of the present invention will be described below with reference to a specific configuration diagram of the present invention in FIG. 1 (FIG. 1A is a configuration diagram of a gyro rotor, and FIG. 1B is a drive circuit diagram). Will be described in detail.
In FIG. 1, the same parts as those in FIGS. 2 to 3 are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 1 (A), a part different from the conventional one is that a permanent magnet 19 is provided in a rotor part 18 of a gyro rotor 16 and
The rotation detecting element 17 for detecting the rotation of the rotor is provided with a rotation detecting element 17 configured by a Hall element that utilizes the Hall effect of generating a voltage when receiving a magnetic field of a permanent magnet, for example. This gyro rotor 16 has a stator portion 21 through windings.
The rotor portion 18 is disposed outside of, and the shaft of the rotor portion 18 is fixed to the case 20 via the bearing of the bearing housing 22 so as to rotate at high speed around the rotation axis (arrow),
It is fixed in the ball 11 by a support shaft 23. Such a gyro rotor 16 is driven by the drive circuit 24 shown in FIG. Although FIG. 1 (B) shows a case where two gyro rotors 16a and 16b are driven, only one of them (16a side, the same applies hereinafter) will be described in the following description (the other is similar). Configuration and operation).

In FIG. 1B, 17 is a rotation detecting element for detecting the number of rotations of the gyro rotor 16. Reference numeral 25 is a reference oscillator that outputs a reference value for the output value of the rotation detecting element (in the embodiment, it is assumed that the Hall element and the comparator circuit are built in, and the output voltage is composed of an IC that takes a binary logic). .
Reference numeral 26 designates the output value of the rotation detecting element 17 and the reference value, for example, two binary counters (hereinafter abbreviated as "counters").
Comparing unit consisting of K ₁ and K ₂ , four NAND gates (hereinafter abbreviated as “gate”) A _{1 to} A ₄ and two NOR gates (hereinafter abbreviated as “gate”) O ₁ and O _2. A comparing / storing circuit that compares the result at 27 and stores the result of the comparison in a storage unit 28 that is configured by a flip-flop (hereinafter abbreviated as “FF”) including two gates A ₅ and A ₆ . Reference numeral 29 is a capacitance changing circuit that activates the relay RL ₂ based on the output value of the comparison / storage circuit 26 to change the overall capacitance of the capacitor.

In FIG. 1 (B), the rotation detecting element 17 is a permanent magnet 19
It is assumed that the output voltage becomes OV when the rotor portion 18 rotates (when the rotor portion 18 rotates, a pulse train P (frequency) of OV and 5V, for example, which is proportional to the rotation speed is obtained). This pulse train P is input to the counter K ₁ of the comparison unit 27.

The counter K ₁ sequentially counts the pulse train P, counts a predetermined pulse train (this time is referred to as P ₁ ), and the high-order digit (hereinafter abbreviated as “MSB”) becomes high, for example, and FF28 via the gate O _1. And a signal for resetting the counter K ₂ via the gate A ₄ . This counter K ₁ receives the next signal of a predetermined pulse train P ₁ (when P ₁ goes low or when it goes to the next pulse train P ₂ ) via gates A ₁ and A ₂ . Will be reset. on the other hand,
The counter K ₂ also inputs the reference value of the pulse train q of the reference oscillator 25 and operates in the same manner as the gate K ₂ . That is, MSB becomes high and becomes a signal for resetting the FF 28 via the gate O ₂ , and becomes a signal for resetting the counter K ₁ via the gate A ₂ . This counter K ₂ is reset by the next signal from the reference oscillator 25 via the gates A ₃ and A ₄ as described above.

According to such a configuration of the comparison unit 27, the gyro rotor 16
While the rotation of the counter is slow and the frequency of the output of the rotation detecting element 17 is lower than the reference value of the reference oscillator 25, the MSB of the counter K ₂ becomes high first and the counter K ₁ is continuously reset. Therefore
The FF 28 is in the reset state, the relay RL ₂ is turned on, and the gyro rotor 16a is driven by the parallel capacitance of the capacitors C ₄ and C ₅ . As the rotation of the gyro rotor 16 increases, the frequency of the output of the rotation detecting element 17 becomes higher than the reference value of the reference oscillator 25. Therefore, conversely to the above, the MSB of the counter K ₁ becomes high before the counter K _2. Is set, the relay RL ₂ is turned off, and the gyro rotor 16 is driven only by the capacity of the capacitor C ₄ .

The gate A ₇ is provided to turn off the relay RL ₂ when both of the two gyro rotors exceed the set rotation speed.

That is, it is for confirming that the rotations of the two gyro rotors are both above a certain level and changing the capacitance of the condenser to smoothly increase the rotations of the two gyro rotors.

Further, 30 is a prevention circuit.This prevention circuit 30 prevents the rotation of the gyro rotor due to the large capacity capacitor before the interruption when the power is interrupted during the operation of the gyro rotor and the power is supplied again. This is provided in order to prevent the drop and to initialize the FF28 to the set state after the power is restored. This prevention circuit 30 may be set in any of the comparison / storage circuits.

<Other Application Examples> The configuration for detecting the rotation of the gyro rotor 16 is not limited to the one described above. For example, the rotation detection element may be an optical element that detects the lightness and darkness by color-coding the rotating portion. Also, it goes without saying that the drive circuit may be provided inside or outside the roller ball. Furthermore, although the above-mentioned technique has been described in the case of using a gyro rotor, the present invention is not limited to this and can be widely used for general induction machines.

<Effects of the Invention> As described above in detail with reference to the embodiments of the present invention,
According to the gyro rotor driving device of the present invention having a configuration in which the rotation speed of the gyro rotor is detected by the rotation detection element, compared with a reference value and stored, and the capacity of the capacitor connected to the induction motor is changed by this output. 1): The switching timing (rotation speed) can be freely set by the frequency of the reference oscillator and is accurate. (2): Most components are IC
Because it can be configured with, it is possible to produce at a small size and light weight at low cost. (3): Since it is a method of switching the capacitor by directly detecting the rotation speed, when used in a gyro compass, it is not affected by line resistance such as supporting liquid resistance and adjustment is made for individual characteristics of the gyro rotor, etc. Operation is stable. (4) The configuration is suitable for a high-speed rotating body such as a gyro rotor.

[Brief description of drawings]

FIG. 1 is a specific configuration diagram of the present invention, FIG. 2 is a schematic configuration diagram of a gyro compass, and FIG. 3 is a diagram for explaining a conventional technique. 11 …… Rolling ball, 16 …… Gyro rotor, 17 …… Rotation detecting element, 24 …… Drive circuit, 25 …… Reference oscillator, 26 …… Comparison / memory circuit, 29 …… Capacity change circuit.

Claims (1)

[Claims] 1. A gyro rotor driving device for reducing the capacity of a capacitor as the rotation speed of a gyro rotor increases so as to smoothly increase the rotation of the gyro rotor up to a synchronous rotation. Detect and
A rotation detection element that outputs a pulse signal corresponding to the number of rotations, and the pulse signal of this rotation detection element counts, outputs an output signal when a certain number is counted, and resets the count by an input reset signal. A first counter, a reference oscillator that outputs a reference pulse signal having a period corresponding to a reference rotation speed that changes the capacitance of the capacitor, and the pulse signal of the reference oscillator is counted to count a fixed number. When the output signal is output at the same time, the count is reset by the input reset signal.
And a capacitance change circuit for reducing the capacitance of the capacitor when the count of the first counter ends earlier than the count of the second counter based on the output signals of the first and second counters. Is provided, and the output signal of the counter that has finished counting earlier resets the other counting counter, controls the capacitance change circuit, and follows the speed change counted by the first counter. A gyro rotor driving device characterized by smoothly increasing the rotation of the gyro rotor.