US2419063A

US2419063A - Gyroscope control

Info

Publication number: US2419063A
Application number: US303734A
Authority: US
Inventors: Fischer Franz
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-11-10
Filing date: 1939-11-10
Publication date: 1947-04-15
Anticipated expiration: 1964-04-15

Description

April 1947- F. FISCHER emoscogg CONTROL Filed Nov. 10, 1939 I Patented Apr. 15, 1947 GYROSCOPE CONTROL Franz Fischer, Berlin-Wilmersdorf, Germany vested in the Attorney General of the United v States ApplicationNovember 10, 1939, Serial No. 303,734

In Germany November 10, 1938 3 Claims. 74-5).

This invention relates to gyroscopes, and more particularly to gyroscopic horizons for vehicles such as aircraft.

Devices have heretofore been proposed oi. this character wherein a gyroscopic horizon is provided with means which are responsive to gravity for imparting stabilizing forces or moments thereto. Such means, for example, pendulums tend to leave their true vertical position when the craft upon which they are mounted changes course or speed thereby producing longitudinal or transverse accelerations. Pendulums under the-action of these'disturbing accelerations will assume an apparent instead of a true vertical position. The stabilizing forces which are dependent upon the position 0! the pendulum will consequently have the effect to move'the plane of the gyroscopic horizon into such a position that it is perpendicular to the apparent vertical rather than the true vertical.

One of the objects of the present invention is to provide novel means for maintaining a gyroscopic horizon in a plane perpendicular to the true vertical.

Another object of the invention is to provide novel means for maintaining a gyroscopic horizon in the true horizontal wherein the effect of the longitudinal or transverse accelerations of a vehicle upon which the novel means are mounted are compensated for.

A further object is to provide novel means for stabilizing a gyroscopic horizon, the directive force of which means is effective at all times during the operation 01' the gyroscopic horizon.

Another object is to provide a gyroscopic horizon which is at all times under the influence of stabilizing means.

The above and further objects and novel features will more fully appear from the detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for purposes of illustration only and are not intended as a definition of the limits of the invention, reference for this latter purpose being had to the appended claims.

In the drawings, wherein like reference characters refer to like parts throughout the-several views,

Fig. l is an isometric view partly in section and partly diagrammatic of one embodiment of the invention;

Fig. 2 is an isometric view partly in section of acceleration compensating means employed with a second embodiment of the invention; and

Fig. 3 is an isometric view of a gravity responsive stabilizing device which may be employed with the embodiment of Fig, 2.

The forms of the invention illustrated in the accompanying drawings, by way of example,

comprise a. conventional"gyroscopic horizon, apparatus having stabilizing means which are constituted by means for exerting a turning moment at a suitable point upon the gyrohorizon, the last named means being a gravity responsive device, for example, a pendulum which governs the stabilizing force producing means in accordance with departures of the gyro horizon from a predetermined relationship with the gravity responsive device. Novel means are provided for stabilizing the gravity responsive device and for compensating for the eiTect of disturbing accelerations thereupon comprising means for measuring accelerations which arise in a, direction of oscillation of the gravity responsive device. The latter, under the action of the stabilizing the true vertical and thus maintains the horizon in the true horizontal plane. T 1

In the foam shown in'F'ig. l-the gyroscopic horizon is constituted by a conventional rotor III which is rotatable on trunnions ii which are mounted for rotation upon an inner gimbal ring l2, the latter being provided with trunnions II.

The latter trunnions are conventionally mounted upon an outer gimbal ring or frame H which is mounted by means of trunnions [5 upon fixed bearings i6, upon a vehicle such as aircraft. The trunnions l5 are parallel to the transverse axis of the craft, the direction of advance of the craft being indicated by arrow l1.

The center of gravity of the gyro rotor preterably coincideswith the point of intersection of the axes of trunnions l3 and i5.

Suitable stabilizing moment producing means which act directly upon the mounting of the gyroscope, and which are controlled by, means which are later to be explained, comprise a rotary magnet it which includes an armature i9 which is rigidly connected to an extension of the I tremity of one of the above mentioned oppositely wound exciter windings. A sliding contact 23a is connected by means of a lead 24 through a power source 25 to a common tapping point of the above mentioned exciter windings.

Resistance 23 and sliding contact :34 comprise parts of the above mentioned gravity responsive device, the remainder of which is constituted .by a mounting member 23 for the resistance 23, the member being preferably rigidly connected to one of the trunnions l5. Sliding contact 23a is rigidly attached to a pendulum 21 which is attached to and mounted for movement with a shaft 23, the latter resting in a fixed bearing 23.

In operation of the apparatus so far described both the windings of the armature i9 are energized equally in the zero or central position of the sliding contact 230. as shown in Fig. 1. Consequently the oppositely acting turning moments acting on a trunnion l3 compensate one another and no stabilizing force is communicated to the gyro. However, if the plane of rotation of the rotor angularly deviates from the horizontal about the axes of trunnions l5, the deviation being due, for example, to bearing friction, the mounting member 26 and therewith the resistance 23 will anzularly shift, thereby moving the sliding resistance 23a away from its central position upon the resistance. The rotarymagnet i3 will exert a turning moment upon the trunnion l3 which corresponds in magnitude and direction to the movement of the resistance 23 and sliding member 23a from the initial position, thereby causing the gym to precess about the outer gimbal trunnions until the mounting member 23 and therewith the resistance 23 are restored to their initial centralized position. Thus the axis of rotation of the rotor will tend to seek a position which is parallel to the longitudinal axis of the pendulum, i. e., the apparent vertical.

Novel means are provided for maintaining the pendulum in the true vertical comprising apparatus for measuring, in the embodiment shown, accelerations in the direction of advance, and for exerting a compensating moment upon the pendulum in response to the measured acceleration. The means are constituted by a rotary magnet 30 having an armature 3| which is preferably rigidly attached to shaft 23 upon which the pendulum is mounted. The armature 3| is provided with a. double winding analogous to the one previously mentioned in connection with rotary magnet l3.

The rotary magnet 33 is operatively connected, in a manner to later appear, with acceleration measuring means comprising a propeller 32 which is rotatable by the relative or head wind and which, by means of a shaft 33 which is provided with slip rings 34, rotates a housing member 35 which is preferably cylindrical. Rotatably mounted within the housing 35 is a shaft 35 upon which is attached a fly wheel 31. Resilient means are provided causing the shaft 35 to rotate with the housing 35 comprising a spring member 33 which is preferably coiled about the shaft, and in a rest position is in the shape of a spiral of Archimedes or a logarithmic curve, as shown in Fig. i. with the inner extremity of the spring.

attached to the shaft and the outer extremity of the spring attached to the housing. Suitable means for damping relative movements of the shaft 35 and member 35 are provided comprising an eddy current damper including, for example. a cylinder 39 upon shaft 33, the cylinder being rotatable within a magnet 43.

The operative interconnection of rotary magnet 33 and the acceleration responsive means comprises a potentiometer device 4| which is constituted by a resistance 42 which. in the form shown, is semi-circular in shape and in contact with a sliding finger 43, the latter being rigidly connected to shaft 35, and the resistance being mounted upon the member 35. The finger 43, by means of the spring 33, lead 44, one of the slip-rings 34, and a lead 45, is connected to the armature 3|. The opposite extremities of the resistance 42, by means of suitable leads, are connected to two of the slip-rings 34 and, by means of leads 43 and 41, are connected to the positive and negative terminals of a source of electric energy. Interconnecting these positive and negative terminals is a resistance 43 to the center of which is connected a lead 43, the latter being also connected to armature 3|.

In operation the angular speed of shaft 33 is proportional to the relative or head wind and therefore to the air speed of the plane. At a constant air speed of a plane. 1. e., ata constant speed of the propeller 32, the housing 35 and the fly wheel 31 are in synchronous rotation and the potentiometer apparatus 4| is in a centralized position as shown in the drawing. However, if due to an acceleration or deceleration the speed of the propeller 32 changes, then the housing 35 is accelerated or decelerated therewith. Fly wheel 31, due to inertia, continues to rotate temporarily at its previous angular speed and the finger 43 of the potentiometer is deflected from the central position in response to the acceleration or deceleration As a result of the coupling by means of the spring 33, the fly wheel 31 and therewith finger 43 are brought to the new speed of rotation of the housing 35 and finger 43 is recentralized.

As long as there exists between the two rotatable members 35 and 31 a relative displacement which is correct in direction, and at least approximately correct in magnitude, to the flight acceleration'or deceleration, then a corresponding relative displacement occurs between the finger 43 and resistance 42 of the potentiometer. The movement of flnger 43 from its central position will cause the rotary magnet 33 to produce a moment which will compensate or balance the disturbing moment created by the acceleration or deceleration of the craft. If the angular speed of the flywheel 31 becomes equal to that of housing 35, then the flnger 43 returns to a central position and the rotary magnet 33 no longer receives electric impulses.

A second embodiment of a measuring device for acceleration is shown in F18. 2 wherein a propeller (not shown) is operatively connected adjacent the armature and rigidly attached to the housing or cylindrical member 5| and adapted for rotation therewith. Also mounted upon housing 5| are diametrically opposed brushes 53 which are in contact with a conventional commutator 51. The diametrically opposed brushes are electrically connected by means of leads 53 and slip-rings 53, there being one lead and one slipbodiment no mechanical coupling is employed.

Consequently, in operation there occurs in the event of an acceleration of the housing 5| relative to the shaft 52 an electromagnet braking action between the armature 54 and the advancing or lagging poles 55. The poles in this manner exert a torque upon th armature which tends to ynchronize the speed of said armature and housing 5|. The current which is created during the relative rotation of the parts of the generator comprises a measure of the angular acceleration of the propeller and is conducted by the commutator, the brushes and connected conductors to the above mentioned rotary magnet.

A modification of the arrangement of the pendulum device and the interconnected rotary magnet above described is illustrated in Fig. 3, which is similar to the above mentioned pendulum device with the exception that a resistance 60, which is analogous to the resistance 23, is rigidly mounted upon the aircraft proper rather than mounted upon a trunnion such as'i'i (Fig. 1).

There is thus provided novel means for maintaining the rotor of a gyroscopic horizon in a correct and true horizontal position, the means being simple in construction and light in weight. Furthermore, the novel means are extremely sensitive but are not easily moved out of adjustment. The parts for the acceleration measurin apparatus are well shielded and only such forces act upon the rotating part thereof which are responsive to the speed and acceleration of the craft.

Although two embodiments of the present invention have been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. For example, instead of employing a propeller to rotate one of the members of the acceleration measuring devices, it is possible to operatively interconnect one of said members directly to the engine of the aircraft. Also it would be possible to control, e. g., shaft 33 by means of a conventional type of speedometer in such a manner that the speed of said shaft is a function of thespeed of the aircraft. Various changes may be made in the design and arrangement of the parts without departing from the spirit and scope of the invention as the same will now be understood by those skilled in the art. For a definition of the limits means, means actuable by electricity for exerting a stabilizing moment upon the true vertical defining means, a generator including an armature and pole shoes, a flywheel drivably connected to the armature, a propeller drivably connected to the pole shoes, and means for electrically connecting the generator and said means actuable by electricity.

2. The combination with a gyro horizon including a gimbal ring suspension, the horizon being mounted upon a vehicle, of means for-exerting a force upon the suspension, means responsive to movements of the gyro from the true vertical for controlling the first named means to return the gyro to said true vertical, a flywheel member, a rotatable member, a propeller operatively connected to the rotatable member, means for resiliently interconnecting the flywheel and rotatable member, and means for exerting a force upon the second named means in response to changes from a predetermined angular relation of said members, whereby said gyro is prevented from assumin an apparent vertical position during acceleration and deceleration of the vehicle.

3. In apparatus of the class described, a gyro rotor mounted in a gimbal ring suspension adapted to. be carried on an aircraft, means for exerting a turning moment upon the suspension, gravity responsive means for governing the firstnamed means, means for exerting a turning moment upon the gravity responsive means, a member rotatable at a speed proportional to the velocity of flight, a fiy wheel resiliently interconnected to said member, and means for controlling the moment exerted-upon said gravity responsive mean in response to changes in angular relationship between the member and fly wheel to preventsaid gravityvresponsive means from estab lishing an apparent vertical.

FRANZ FISCHER.

REFERENCES CITED The following references are of record in the file of this patent: UNITED STATES "PATENTS Number