RU2460040C1 - Gyroscope (versions) - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: as per the first version, gyroscope includes housing 1 inside which there located is hydraulic motor comprising of stator 2 with coils creating rotary magnetic field actuating rotor 3 on spherical ball-bearing support 4. Ferrite ring 5 of rectangular section is rigidly fixed in end part of rotor 3 as movable element of angle transmitters and moment transmitters. Angle transmitters 6 and moment transmitters 7 are arranged on housing 1 of gyroscope opposite ferrite ring 5. As per the second version of gyroscope, steel ring of rectangular section is rigidly fixed on inner surface of ferrite ring 5.

EFFECT: invention allows improving accuracy parameters and enlarging the range of measured angular speeds.

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Description

The invention relates to instrumentation and can be used to create gimballess gyroscopes on a spherical ball bearing, which can be used, for example, as sensitive elements of gyrostabilizers or two-channel angular velocity meters.

Known gyroscope [1] containing a housing, a gyromotor, cardan suspension, angle sensors and torque sensors, rotated relative to each other by 90 ° around the longitudinal axis of the gyroscope.

The main disadvantage of this gyroscope is the presence of a cardan suspension, which leads to a significant drift of the gyroscope due to the need to use current leads to supply power to the windings of the gyromotor, angle sensors and torque sensors and ball bearings to ensure rotation of the frames of the cardan suspension.

The closest in technical essence to the claimed device is a gyroscope [2], comprising a housing with a hermetically sealed cover, a gyromotor, a rotor on a spherical ball bearing, transformer-inductive angle sensors and electromagnetic torque sensors. The stator of the gyrodrive consists of two burst packages, separated by a non-magnetic element, and a winding, the turns of which cover both packages. The winding of the gyromotor, in addition to its main function (creating a rotating magnetic field that rotates the rotor), performs the function of the primary winding of the transformer-inductive angle sensor. The secondary windings of the angle sensors are wound separately on each package, with each pair of windings geometrically offset relative to each other by 90 °, which allows measurements on two axes. With a symmetric arrangement of the hysteresis rotor ring relative to the stator packets, the same EMF will be induced in the windings of the angle sensors. When this ring is shifted to either side, the magnitude of the induced EMF in the windings of the angle sensors will be different. The torque sensors are structurally made similarly to angle sensors and are geometrically shifted relative to them by 90 °.

The disadvantage of this gyroscope is: its low accuracy of measuring the useful signal, caused by the presence of interference caused by the operation of the gyromotor due to eddy currents as a result of using the hysteresis ring of the rotor as a movable element (rotor) of the angle sensors; limited range of measured angular velocities (due to the small shoulder, the torque sensor is a moving element); the impossibility of correcting the drift of the gyroscope, depending on the moment of rotation of the electromagnetic field created by the stator, since in this case the hysteresis ring must be demagnetized and cannot be a moving element (rotor) of angle sensors and torque sensors [3].

The aim of the invention is to improve the accuracy of the gyroscope and the expansion of the range of measured angular velocities.

To achieve this, in the first version of the gyroscope, comprising a housing with a gyrodrive located inside it, including a stator with coils and a rotor on a spherical ball bearing, transformer-inductive angle sensors and electromagnetic torque sensors, according to the invention, in the end part of the rotor as a movable sensor element angle and moment sensors, a ferrite ring of rectangular cross section is rigidly fixed, and angle sensors and moment sensors are placed on the gyroscope body opposite the ferrite ring.

The second version of the gyroscope is characterized in that a steel ring of rectangular cross section is fixedly fixed inside the ferrite ring.

Significant differences of the proposed gyroscope compared with the known one is the introduction of a rigidly fixed rectangular ferrite ring into the end part of the rotor, which acts as a movable element of the angle and moment sensors, which are placed on the gyroscope body opposite the ferrite ring. A significant difference between the second version of the gyroscope is the introduction of an additional steel ring inside the ferrite.

These significant differences can improve the accuracy of the gyroscope by eliminating interference in the useful signal generated by the operation of the gyrodrive, and expand the range of measured angular velocities by increasing the arm of the torque sensor - a movable element.

The invention is illustrated by drawings.

Figure 1 presents the first version of the proposed gyroscope side view in section; figure 2 is a view of the first option in section along the line aa; figure 3 - diagram of the operation of the angle sensors; figure 4 - scheme of operation of the torque sensors; figure 5 is a side view of a second variant of the proposed gyroscope in side view.

In the proposed preferred implementation of the gyroscope according to the first embodiment, the gyroscope rotor 3 (with a hysteresis ring 8 and a ferrite ring 5) has a bell-shaped shape and is installed in the inner ring of the spherical ball bearing 4. The spherical ball bearing 4 provides three degrees of freedom of the rotor 3, allowing an unlimited rotation angle around own rotation axis (X axis) and limited angles (± 45 ') of rotation around the other two axes (Y and Z). The rotor 3 is driven by a gyro motor, the stator 2 of which is mounted on the outer ring of the spherical ball bearing 4. The radial ball bearing 10 acts as a stop and serves to limit the rotation angles of the rotor 3 around the axes Y and Z.

To register the angle of rotation of the rotor 3 around the measuring axes Y and Z, angle sensors 6 are designed, the fixed (stator) part of which is made, for example, in the form of a U-shaped core, on which two identical coils 12 are worn, one of these coils is an excitation winding, and the second with a signal winding. The angle sensor 6 for each channel contains two such cores with coils 12 located diametrically and offset relative to the gyro sensitivity axes by an angle of 45 ° (FIG. 2, FIG. 3). The excitation windings of the angle sensor of one channel are connected in series and connected in parallel with the excitation windings of the angle sensor of another channel to an alternating current source U, for example, with a voltage of ~ 8 V, frequency 11,600 Hz. The signal windings are connected in a differential circuit. With this switching on of the windings, the steepness of the sensor increases compared to other switching schemes. When a supply voltage is applied to the field windings of the angle sensor 6, the voltage is transformed on the signal windings. The total value of this voltage on both signal windings is practically independent of the position of the rotor 3 (at small rotation angles) and plays the role of the supply voltage of the bridge circuit. The air gaps δ ₁ and δ ₂ between the ferrite ring 5 and the cores of the angle sensor 6 at the neutral position of the rotor 3 are equal to δ ₁ = δ ₂ , the inductances of both signal windings are the same and the bridge is balanced.

When the rotor 3 is rotated relative to the neutral, for example, by an angle ψ (Fig. 3), the indicated air gaps change: for one core, the air gap increases, and for the other it decreases. In this case, the inductance of one signal winding increases, and the other decreases. As a result, the balance of the bridge is violated and a voltage proportional to the doubled angle of rotation of the rotor 3 appears on the output diagonal of the bridge circuit. A change in the direction of rotation of the rotor 3 causes a 180 ° change in the phase of the output voltage, i.e. The characteristic of the angle sensor 6 is reversible. Zero adjustment of the angle sensor 6 is carried out, for example, by shifting the coils 12 of the signal windings.

The selected scheme of operation of the sensors of the 6th angle combines the advantages of transformer and inductive sensors. It does not create, relative to the measuring axis, the moment of dry friction forces, because is non-contact, and the moments due to the forces of attraction of the rotor to the cores are directed in opposite directions and therefore are almost completely compensated.

To create control moments, electromagnetic sensors 7 of the moment, working on direct current, are used. Structurally, the torque sensor 7 is similar to the angle sensor 6 and contains two channels, diametrically located on the housing 1 and combined with the sensitivity axes of the core gyroscope, for example, from cermet. A control coil 14 is put on the middle rod of each core, for example, having a U-shape, (FIG. 2, FIG. 4). The main advantage of electromagnetic sensors is their structural and technological simplicity and the possibility of obtaining significant moments.

A movable element (rotor) common to angle sensors 6 and moment sensors 7 is a ferrite ring 5, for example, from material M2000 NM1-17 PYAO.707.094 TU. The ferrite ring 5 is located in the end part of the rotor 3 and does not interfere in the signal windings of the angle sensors 6 created by the operation of the gyro motor.

The gyroscope is closed by a casing 9, is sealed and filled with a helium-hydrogen mixture to a pressure of, for example, 750 mm Hg. in order to reduce the aerodynamic moment of resistance and its effect on the drift of the gyroscope (through the projection of this moment on the axis of sensitivity of the gyroscope). For removal and supply of electrical signals, pressurizes 13.

In the second version of the gyroscope (Fig. 5), a steel ring 15 is fixedly fixed inside the ferrite ring 5, for example, steel material 20895 GOST 11036-75. Due to this, the steepness of the characteristic of the torque sensor increases and, therefore, the measured angular velocity increases when the gyroscope is operating at elevated temperatures.

The gyroscope works as follows. In the zero position due to symmetry, the output signal from the angle sensors 6 is absent. In the measurement mode, if there is an angular velocity, for example, relative to the Y axis, the gyroscope body 1 will begin to turn around this axis, and the rotor 3 will tend to keep the kinetic moment vector direction unchanged in inertial space. The gaps δ ₁ and δ ₂ between the ferrite ring 5 and the end surfaces of the cores of the angle sensors 6 will change and a signal will appear at the output of the angle sensor 6, the amplitude of which is proportional to the measured angle, and the phase determines the sign of the angular displacement. This signal is electrically processed and supplied to the coils of the torque sensor 7 along the Z axis, while the rotor 3 will precess (rotate) with respect to the Y axis according to the gyroscopy rule, trying to reduce the mismatch on the angle sensor 6 to zero. A measure of the angular velocity is the current in the coils of the sensor 7 of the moment. Quadratic dependence

where w is the measured angular velocity;

k is the scale factor of the torque sensor;

I is the current in the coil of the torque sensor.

When using the gyroscope as a sensitive element of the gyrostabilizer, the signal from the angle sensor 6 is electrically processed and fed, for example, to the gyro stabilizer unloading engine. The gyroscope torque sensor 7 is used either to compensate for the drift of the gyro platform, or to control, if necessary, the turn of the gyro platform.

Thus, in comparison with the prototype, the use of the proposed device as sensitive elements of gyrostabilizers or two-channel angular velocity meters improves the accuracy parameters and widens the range of measured angular velocities.

Information sources

1. AS of the USSR No. 431808 Three-stage gyroscope // IPC G01C 19/00, declared on 11.26.1971

2. US patent No. 3517562, NKI 74 / 5.6, IPC G01C 19/28, issued June 30, 1970 (prototype).

3. RF patent No. 2410658, IPC G01M 1/34, 2009

Claims (2)

1. A gyroscope containing a housing with a gyrodrive located inside it, including a stator with coils and a rotor on a spherical ball bearing, transformer-inductive angle sensors and electromagnetic torque sensors, characterized in that in the end part of the rotor, as a movable element of angle sensors and sensors moment, a ferrite ring of rectangular cross section is rigidly fixed, and angle sensors and moment sensors are placed on the gyroscope case opposite the ferrite ring. 2. A gyroscope containing a housing with a gyrodrive located inside it, including a stator with coils and a rotor on a spherical ball bearing, transformer-inductive angle sensors and electromagnetic torque sensors, characterized in that in the end part of the rotor, as a movable element of angle sensors and sensors moment, a ferrite ring of rectangular section is rigidly fixed, inside which a steel ring of rectangular section is fixedly fixed, and angle sensors and torque sensors are placed on the body castrated contrast ferrite ring.

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