US1677331A - Gyroscopic apparatus - Google Patents

Description

July 17, 1928.

A. CHESSIN GYROSCOPIC APPARATUS Filed Dec. 23, 1919 WITNESSES:

Patented July 1 7, 1928.

UNITED STATES PATENT OFFICE.

ALEXANDER GHESSIN, OF NEW YORK, N. Y.

eYnoscorIo APPARATUS.

Application filed December 23, 1919. Serial No. 346,921.

gravity, will retain its direction in absolute space, i. e. in the space in which our earth.

1s moving. The axis of such a gyroscope, if set in the meridian of the place of observation, will accordingly, move away from this meridian as the earth rotates. Gyroscopic compasses, therefore, must be provided with means for driving the gyro axis towards the meridian. In present day devices, this so called precession of the gyroscope is effected either directly, or indirectly, by means of a gravity torque. It is'an important and distinctivefeature of my invention that no such use is made of gravity and that the means for driving or spinning the gyroscope constitute also means for causing it to precess towards the meridian.

Another important feature of my invention is its simplicity, because all the elements needed to make it function as a compass are combined in the means for spinning the gyroscope.

A further and new feature of importance is the motor, which provides both the power for spinning the gyroscope and the power for making it precess.

The use of magnetic pull, in lieu of gravity, torause precession, forms also a new and useful feature. Other novel features will appear from the detailed description of my invention.

Before passing to this description, let it he noted that only parts of the complete structure in each case are shown in the draw mgs, namely, the parts which directly embody the new features. Thus, although the.

specifications and drawings, as shown, have reference, in particular, to marine compasses. the gimbal rings, in which the described parts would be suspended in the well known manner, are omitted so as not to complicate the drawings. Likewise, no invention being claimed of the manner of frictionless suspension used for the specified and described parts, various forms of such spension are either briefly indicated, or merely assumed, again, in order not to complicate the drawings with irrelevant matter. This method of omitting well known devices from the specifications and drawings is adhered to t roughout.

' It may be well, also, to define at the outset certain terms used in the description of my invention. One of these terms is axis of the driving torque. A torque being equivalent to a couple of forces, the axis of the torque is the axis of this equivalent couple. The torque itself is represented by a line of definite length and direction, and we may speak of its components just as we speak of the components of a force. Another term, viz: normally, used in reference to horizontal or vertical axes, relates to positions under, conditions of perfect equilibrium,i. e. when the structure suspended in gimbals is not swinging, and the gyroaxis itself is at rest. Finally, while I avoid the use of the word precession in general, I have retained it, in preference to the word turning, for the movement of the gyroscope towards the meridian, because the use of the term precession in this connection has become familiar in the art.

Referring to the accompanying drawings:

' Figure 1 is a vertical cross section of a gyroscopic device illustrating one of the preferred forms of my invention. The gyroscope, in this case, is the rotor of an. electric motor and it can tilt relatively to the stator, which forms a art of the casing shown in cross section, t e casing itself being suspended in a torsionless manner, although the mechanism which makes the suspension torsionless is not shown. 1

Figure 2 is a horizontal cross section of the same device.

Figure 3 is a front elevation of another form of my invention, in'which the gyroscope is made to spin by the impact of a jet of liquid or gas.

Figure 4 is a detail of this second form of my invention, being a top view of the spinning body.

Figure 5 is a diagram of the forces acting in this, and in the preceding, cases, the diagram on the right being for the first, the preferred, form, and the diagram on-the left for the second form. l

Figure 6 is a front elevation, and Figure 7 a side elevation, of a third form of my invention, in which any method of spinning the gyroscope may be used.

Figure 8 is a front elevation of still another form of my invention. A frictionless suspension is assumed in this and in the preceding forms, although only ordinary bearings are shown in the drawings.

Certain portions of Figure 3 are shown in cross section to better illustrate the operation for that form of my invention.

In the following description and claims,

' specific names are necessarily used for identifying parts, but they are intended to be as generic in their application to similar parts as the art will permit.

When the meridian is mentioned, it is always in reference to the meridian of the place of observation, or, more correctly, in reference to the meridian at the center of the roscope.

Re erring particularly to Figures 1 and 2, 1 is a cross section of a casing which contains an induction motor;2 is the stator of this induction motor and is an integral part of the casing with which it is connected by means of extensions 3 which are arranged to leave open spaces for the swinging of the ring 4. This ring 4 is rotatably mounted in the casing at 5 and carries the rotor 6 of the induction motor, the rotor itself constituting the gyroscope in this case. The

casing 1 is suspended in a torsionless manner, indicated diagrammatically by the wire 7, from a frame not shown in the drawing, and it is assumed that this latter frame is connected with the body carrying the whole apparatus by means of gimbals in the well known manner.

The principle of operation of this device as a compass will now be explained. Let the gyroscope axle, i. e. the axle of the rotor, be set horizontally, away from the meridian. As the Earth rotates, the gyroscope developes a tendency to tilt relatively to the horizon, as is indicated on Figure 1 by the dotted lines. The magnetic pull between the stator and the rotor of the induction motor will draw the rotor back into the position indicated on Figure 1 by the full lines. In. ac-

' the meridian,

cordance with the well known action of gyroscopes, this will effect a turning motion, or precession, of the rotor, together with the casing, about the vertical towards the meridian. This action is reversed when the gyroscope axle passes to the other side of and the gyroscope will oscillate back and forth about this meridian.

The forces developed by the tendency of the rotor to tilt relatively to the stator are shown diagrammatically on the right side of Figure 5, for the upper halfpf the rotor when the rotor is inclined in a direction opposite to the one indicated on Figure 1. symmetrically disposed forces, with directions reversed, act on the lower half of the rotor. It will be observed that the resultant f of the magnetic pull gives a component P which drives or spins the rotor and a component P which draws the rotor back from its inclined position. It will be further observed that the point of application of this resultant of the magnetic pull is off the equatorial plane of the rotor. Therefore, besides the torque which causes the rotor to turn with the ring 4 in the bearings 5, which we may call the precessional torque, a torque is developed about the line M of Figure 1, and the vertical component of this latter torque is such as to oppose the swinging motion of the gyroscope about the vertical. This opposition is maximum at the moment when the gyroscope passes the meridian (because at this moment the axle of the rotor makes its maximum angle with the horizon), and it is minimum when the gyroscope reaches the end of a precessional swing (because at such times the gyroscope axle is horizontal). The result is that the oscillations of the gyroscope about the meridian are damped, i. e. the swings steadily diminish in amplitude.

Referring now particularly to Figure 3, the casing l of the preferred form is replaced by the frame 8, having a hollow base:

9 which rests on an air cushion inside the base 10 of a frame 11, the frame 8 being rotatably mounted in the frame 11 on pivots 12. The air, which is supplied by means of a flexible tube 13, enters the base 10 of the frame 11 through perforations centrally disposed and is allowed partly to escape through the open space 14 and part1 to enter the hollow base 9 through perforations in its bottom, whence the air is led into the nozzles 15 through ducts in the pil-- lars 16 of the frame 8. The ring 4 of the preferred form is here replaced bythc ring 17 rotatably mounted in the frame 8 at 18. The ring 17 carries the spinning body 19 rotatably mounted in this ring at 20. The spinning body is in the form of a wheel having curved blades 21. The principle of operation in. this device is similar to that of my preferred form. lVhen the axis of spin of the gyroscope wheel is inclined to the horizon, the jet, of air from the nozzle 15 strikes the blades 21 off their centers, forcing the wheels axle back into a horizontal position, which, again, results in precession of the body about the tions about the meridian. The diagram of forces, shown on the left of Figure 5, in which f now represents the component of the air impulse normal to the blade curve, again illustrates the fact that a force f is produced for driving the wheel and a force f for causing it to return to the vertical vertical and oscilla-,

Ilia

cation of the force f being off the equatorial plane of the wheel, atorque is produced about the vertical which effects a damping of the bodys oscillations about the meridian.

Passing on to Figure: 6 and 7, the upper and lower circular discs 22, connected by the uprights .23, constitute a frame, corresponding to the frame 8 of the preceding case. This frame is rotatably mounted on pivots 24 in another frame 25, corresponding to the frame 11 of the preceding case. While only ordinary pivot bearings are shown, any one of the known types of mounting for frictionless rotation about the vertical is assumed and would be adopted in practice. A frame 26 is rotatably mounted in the uprights 23 at 27, and carries a gyroscope28 pivoted in the frame 26 at 29. The two discs 22 carry each a permanent or an eleotromagnet 30. The frame 26 has portions 31 of soft iron which are affected by the magnetic pull of the magnets 30 when the gyroscope tilts relatively to the horizon.

Figure 8 illustrates a form of my invention wherein centrifugal forces are utilized to arrive at the same refults as in my preferred form. Two gyroscopes 37 are shown, connected by means of universal joints 38 at their respective centers with the driving axles of two motors 33 and 34, these motors being jointly mounted in the frame 32 for. free rotation about a vertical axis. The two motors rotate in opposite direction so that they exercise no gyroscopic effect. The two gyroscopes 37, however, spin in the same direction. This is effected by means of reversing gears enclosed in the casing 35 which is attached to one of the motors, a counterweight 36 being attached to the other motor to preserve balance. The action of centrifugal forces, when the gyroscopes are inclined to the driving axles of the motors, is to draw the gyroscopes into positions wherein their axes of spin coincide with the axes of the driving axles of the motors. The result is in every way similar to that observed and explained for my preferred and for my second forms of invention.

Itshould be observed that, owing to the damping feature of my invention, as in other gyroc'opic compasses having this feature, the gyro-axis, when at rest, is not exactly horizontal, nor exactly in the meridian, but makes a very small angle with the meridian and is slightly inclined to the horizon. There are numerous ways to compensate for the slight deficetaon from the exact NS position, and various means are known to the art for making the compass card read dead-beat. Compen ating devices include other corrections, such as, for instance, corrections for latitude changes. These and similar corrective means are omitted from my specifications, drawings and claims, forreasons already stated in the preamble to the description, but it is to be under'tood that they are omitted without prejudice to the appended claims, wherein reference is made to a definite position relatively to the meridian, rather than to the meridian itself, having in mind the slight angle which the gyro-axis, without the above mentioned corrections, makes with the meridian, in its position of rest relatively to the Earth. It

will further be understood that various omissions, substitutions and changes in the form and in the details of my device and in its operation may be made by those skilled in the art, without departing from the spirit of the invention.

Having duly described my claim:

1. A gyroscopic compass comprising a framesuspended for rotation, about a vertical axis, a gyroscope mounted in said frame to tilt about a horizontal axis, and means to spin said gyroscope, which means exert a torque on the gyroscope about said horizontal axis to resist the tilting thereof.

2. An apparatus comprising a frame mounted for rotation about an axis, a gyroscope mounted in said frame to tilt about a second axis, and means to spin said gyro scope, which means exert .a torque on the gyroscope'about said second axis to resist the tilting thereof.

3. A gyroscopic compass comprising a frame, means whereby said frame is suspended for rotation about a vertical axis, a gyro fcope pivotally mounted in said frame to tilt about a horizontal axis at right angles to its axis of spin, and electro-magnetic means to spin said gyroscope and resist-the tilting thereof. I

4. The combination with a gyroscope mounted to turn about an axis other than invention, I

its axis of spin, of means to spin said gyroscope, which means exert a torque on said gyroscope about said other axis to resist turnin thereof about sald other axis.

5. The combination with a gyroscope having substantially three degrees of rotational freedom, of means to spin said gyroscope, which means exert a torque on said gyroscope about an axis other than the axis of spin, to restrain the rotational freedom of the gyroscope about said other axis.

6. The combination with a. gyroscope hav ing substantially three degrees of rotational freedom, of means for spinning said gyroscop'ev about one axis, said means exerting a torque onthe gyroscope having components about two other axes to restrain rotational freedom of the gyroscope about said two other axes. g

7. The combination with a. gyroscope, of means whereby said gyroscope is mounte to tilt about an axis and to spin about another axis, of electromagnetic means to spin said gyroscope and resist tilting about said other axis. r

8. In a gyroscopic compass, a frame mounted for free rotation about a vertical axis, a second frame mounted in the first frame to turn about a horizontal axis, a gyroscope mounted in the second frame to spin about an'axis perpendicular to'said hori-' zontal axis, and means to spin saidgyroscope,

said means exerting a torque about said horizontal axis to resist turning of said second frame;

9. In gyroscopic compass, a structure mounted for free rotation about'a vertical axis and comprising a frame, a second frame pivoted in the first frame to turn about a horizontal axis, and a motor composed of a stator and a rotor, said stator being integral \With said first frame and said rotor being pivoted in said second frame to spin about an axis perpendicular to said horizontal axis, said motor comprising means for exerting a torque about'said horizontal axis to resist turning of said second frame.

'10. in a gyroscopic compass, a frame, means whereby said frame is suspended for free rotation about a vertical axis, a second frame pivoted in the first frame to rotate about a horizontal axis, a gyroscope pivoted in said second frame to spin about a normally horizontal axis perpendicular to said first mentioned horizontal axis, and electromagnetic means to spin said gyroscope and resist deviation of its axis of spin from a horizontal position.

11. A gyroscopic compass comprising a frame, means whereby said frame is suspended for free rotation about a vertical axis, a gyroscope mounted in said frame to freely turn about a horizontal axis perpendicular to its axis of spin when the gyroscope is not spinning, and means for exerting a torque a out said horizontal axis to resist turning of said gyroscope thereon when the gyroscope spins.

' 12. A gyroscopic apparatus comprising a frame, means whereby said frame is mounted for free rotation about an axis, a gyroscope mounted in said frame to freely turn about a second axis other than 't-s axis of spin when the gyroscope is not spinning, and means for exerting a torque about said second axis to resist turning of said gyroscope thereon when the gyroscope spins.

" 13. A gyroscopic comp-ass comprising a frame suspended for free rotation about a vertical axis, a, gyroscope mounted in said frame to tilt about a horizontal axis perpendicular to its axis of spin, and means to resist the-tilting of said gyroscope within a predetermined angle, which means become inoperative upon the tilting of said gyroscope exceeding said predetermined angle.

14. A gyroscopic apparatus comprising a frame mounted for free rotation about an axis, a gyroscope mounted in said frame to turn about a second axis other than its axis of spin, and means to resist turning about said second axis Within a predetermined angle, which/means become inoperative upon the tilting of said gyroscope exceeding said predetermined angle.

15. An apparatus comprising a motor mounted for rotation about an axis and composed of a stator and a rotor which may turn relatively to one another about a second axis perpendicular to the rotor axle, said motor being adapted to resist relative turning of the stator and the rotor about said second axis within an angle not exceeding a predetermined angle.

16. An apparatus comprising a frame mounted for rotation about an axis, and an electric motor, the stator of said motor being attached to said frame, and the rotor being mounted therein to tilt relatively to said stator.

17. An apparatus comprising a frame mounted for rotation about a vertical axis, and an electric motor, the stator of said motor being attached to said frame, and the rotor being mounted therein to tilt about a horizontal axis.

18. In a gyroscopic comp-ass, means comprising a motor suspended for rotation about a vertical axis and composed of a stator and a rotor which may tilt relatively to one another about a horizontal axis, for producing a torque upon a relative tilt therebetween, said torque having components about both of said axes.

19. In a gyroscopic apparatus, means com prising a motor mounted for rotation about an axis and composed ofa stator and a rotor which. may. tiltrelatively to one another about a second axis, for producing a torque upon a relative t-ilt therebetween, having a component about said second axis.

ALEXANDER CHESS-IN.

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