US875036A

US875036A - Gyroscope.

Info

Publication number: US875036A
Application number: US33272306A
Authority: US
Inventors: Narciss Ach
Original assignee: Individual
Current assignee: Individual
Priority date: 1906-08-30
Filing date: 1906-08-30
Publication date: 1907-12-31
Anticipated expiration: 1924-12-31

Description

N. AGH. GYROSGOPE.

APPLICATION FILED AUG. 30, 1906.

PATENTED DEC. 31, 1907.

1 3 SHEETS-SHEET 3.

Fig. 5.

. I15 16 460 El"- 46 7'55 137 1 ,1111 1% 1 1 0 I 46 HI 460 6 10 12 I 11 & j 3 8 No. 875,036. PATENTED DEC. 31, 1907. N. AGH.

I GYROSGOPE.

APPLICATION FILED AUG: so. 1906.

3 SHEETS-SHEET 2.

No; 875,036. PATENTBD DEC. 31 190.7.

N. AGH.

GYROSGOPE. APPLICATION FILED AUG. 30, 1906.

3 SHEETS-SHEET 1.

a scope in spite of arbitrary movements of the 17, 18 on

bearings

19, 20. .The bearing 19 is UNITED STATES PATENT OFFICE.

NARc s s AGH, or MARBURG, GERMANY.

GYBOSCOPE.

Specification of Letters Patent.

Patented Dec. 31, 1907.

Application filed August 30. 1906. Serial No. 332,723.

have invented certain new and useful Improvements in and Relating to Gyroscopes, of which the following is a specification.

My invention relates to gyroscopes and has for its object to provide such improvements in gyroscopes which secure the invariabilityv of the axis of. rotation of the gyrocarrier of the gyroscope.

Therefore my invention com rises means to do away with the influence o gravity acting on the spinning body and causing frictionv between the axle and its bearing which undergoes changes on variation of the inclination of the axis of rota-tiontowards the horizontal plane.

My invention furthermore comprises means for securing an invariable position of the axis of rotation of the spinning body and of the rotatable frames forming support for same with relation to their carrier in spite .of any rotations of the support of such gyroscope carrier.

. Other objects of my invention will become clear from the following specification and the annexed drawings forming part of same.

In the drawings Figure 1 is a verticalsectional view of an embodiment of my invention. Fig. 2 is a side elevation of the rota table frame carrying the axle of the spinning body of the gyroscope. Fig. 3 is a detail view showing a modified device for securing an invariable inclination-of the revo-. luble axle of'the spinning body. Fig. 4 is a detail view of a modified form of connection between the spinning body and its carrying shaft. Fig. 5 shows diagrammatically part of a modification, in which each of the two y rotatable frames of the gyroscope is controlling an actuating device for the platform carrying the gyroscope. This figure at the same time illustrates a spinning body consisting of a hollow ring divided into cavities by partitions.

In the drawings 1 designates the platform of a ship or some other object on which it is intended to use the gyroscope.

2 is a double acting pump forming a curved tube and containing a piston 3 carrying a ring-shaped rod 4 firmly connected to a plate 5.

' I 6 is a pillar mounted on the plate by a taining the electromotor12.

meral 38.

' ball-bearing 7 and carrying a Worm wheel 8.

9 is a worm meshing with said worm wheel and mounted on an axle 10 which forms the common axle of two electromotorsll, 12.

13 is a source of electric power. The

electromotors

11, 12 are included in the'current circuit of such electric source in such a manner that the two motors tend to rotate the axle 10 in o posite directions.

On the pillar 6 is mounted a platform 14 carrying a column 15.

16 is a rotatable frame mounted by pins revolubly mounted in the column and the bearing 20 is revolubly mounted in a bracket 21. The

bearings

19, 20 are provided with

pulleys

22, 23 respectively.-

24 is an axle mounted in a bracket 25 of the platform 14 and driven by a motor 26 which is likewise mounted on the platform 14. Mounted on the axle 24 are

ulleys

27, 28 which are connected with

pul eys

22, 23

by

cords

29, 30 respectively, said cords com municating rotation in opposite directions to said

pulleys

22, 23 and

bearings

19, 20.

31' is a pole piece rigidly connected with the frame 16 and immersed into a receptacle 32 containing a fluid 33 forming a resistance included in the electric current circuit con pole. piece also immersed into fluid-resistance 33 opposite the pole piece 31 and rigidly .mounted whereas the pole piece 31 is adapted to follow the movements of frame 16. The current conductorsincluding the said

electromotors

11, 12 and the fluid-resistance 33 are clearly indicated on the drawing.

35 is a frame rotatably mounted inthe frame 16 and 'carrying the axle 36 of the The axis of rotation of spinning body 37.

16 is indicated by the nuframe 35 in frame The axle 36 of the spinning body 37 is provided at one end with a disk 39 havinga ballbearing 40.

41 are supporting pieces for the balls which are connected by links 42 with the frame 35.

43 are springs mounted on the frame 35 34 is a second and having a tendency to raise the supporting pieces 41 which, are made of flexible metal, which permits the springs 43 to relieve the pressure on the pointed end of the axle 36 when the frame 35 is inclined so that the bearing 44 is downward, the tendency of the springs 43 being to push the supporting inclined posipoint, said point running in a bearing 44 carriedby the frame 35 and adjustable in axial direction. v

The spinni body 37 is rovided with a heavy run 45 orming a hol ow ring Figs. 1 and 2 or a ring provided with a number of cavities symmetrically arranged all around said rin The cavity or the several cavities of the ring 45 which are separated from each other by partitions 460, Fig. 5 are filled ,with a heavy material of fluid, granular orpulverulent condition, for instance mercury or metal filings. The filling material of the cavities of ring 45 is indicated on the drawing with the numeral 46. Firmly connected with frame 35 are current-inducing bodies 47 of two electromotors for currents with more than one phase. The numerals 48 designate the induced bodies of the said electromotors, such induced bodies being mounted on the axle 36 of the spinning body 37. The inducing bodies 47 encircling the induced bodies 48, as is clearly shown on the drawing. 49 and 50 are two coils carried by frame 35 and included in the circuit of a source of electric. power 51. The connectlon betweensaid two

coils

49, 50 and the poles of thesource of electric power 51 are clearly shown on the drawing.

.52 1s an iron core shiftably mounted withinthe coils 49 and 50 and adapted to be moved towards one side or the other depending from the kind of energizing the

coils

49 and 50. 53 is a ri shaped vessel mounted on plate 14 and iilled with-mercury 54.

55 and 56 are metallic rods connected to frame 35 and forming art of the current-cirference-b etween the kmd of supportmgof cuits which include coils 49 and 50.

The one pole of the source of electric power 511s connected to the mercury filling 54 of ,the ring-shaped vessel 53 so that energizing 'of

coils

49 and 50 only takes place when the corresponding circuits are closed by immersng of

rods

55 or,5,6 into the mercury filling 54. The circuit connections are arrangedv in. such a manner that the current flows through coils .49 and 50 in opposite directions.

' In Fig. 3 I have shown a modification of the last named device in which the coils 49 and 50'are not fixed to frame 35 but to frame 16 whereas the iron core 52 is fixed to 1' frame 35 in substantially vertical position.

shown in Fi 4

heavy bodies

57, 58 are connected' to t e revoluble axlewhich in this e -case is ag'ain designated with the numeral 36,

I i has in the otherfigures, by

wires

59 and 60.

The

wires

59 and 60 prevent the flying away of the heavy bodies 57 58 on rotation of the axle 36. Referrin now to the embodiment of the invention 3 own in Figs. 1 and 2-the opera tion of the device described is as follows: Assuming that the platform 1 is the platform of a ship and the shi is moving on the sea, then the waves 0 the sea will cause the platform of theship to continuously change its inclination towards the horizontal plane. Y

If now the device is placed on the latform of the shi in such a manner that t e cylinder of the ouble-acting pump 2 is in vertical direction to the lon 'tudinal axis of the ship then the ring4 of t e pump will be moved by known means, which are not re resented on the drawing and which do not orm the object of this invention, in such a manner that the rollin movement of the ship is compensated so t at the plate 5 'in a direction parallel to rin 4 remains always horizontal In the embo iment shown on the drawin only means are provided for compensating t e variable inclinations of the platform of the ship towards the horizontal plane in one sin le d1- rection, say in the direction perpendic ar to the longitudinal axis of the shi Of course it would be possible to provi e also means for taking up the variable inclinations of the platform of the ship with relation to the horizontal plane-in everyother direction.

a The effect of a device like the double-actingdpump 2 is this that the plate 5 is rigidly-- he 100 in horizontal position, although the platform 1 is rolling and that the horizontal position is'not altered even if a pressure asymmetrical to the point in which the plate is sup orted' by ring 4 is exerted on the surface of t e plate, for lnstance at the point ofthe electric source 13. This is an essential difthe gyroscope used in connection with my invention and the supportlng of the gyroscope by means of a system suspended after -the manner of Cardan.

If new the ship runs continuously in one definite direction, the parts of the gyroscope system will remain in their position with relation to the plate 5. However if the shi ,which. all this time is rotatingwith highwalocity has a tendency to retain its original direction of axis of rotation. Now the telidency of the members connecting-the platform 1 of the ship with the axis of rotation of the spinni body to deviatesaid axis is overcorheb t eelectrical means for adjust- 3 ing the positionof plate 14 with relation to plate 5. .Namely't ese adjusting means op- 1'1 5 alters the direction of its course this wou d erate in such a manner that onturning of of said motor in such a manner that the axle of the two

motors

11, 12 is rotated till the resistance in said current of the motor 12 has attained again the value of the original .position of the parts. The rotation of the axle 10 produces a rotation of the pillar 6 with plate 14. This rotation of the plate 14 now produces on frame 16 substantially the'same rotating tendency as the tendency of the displacement of parts produced by the alterat'ion of the direction of the course of the ship.

In this way the effect of the alteration of the course of the ship on the direction of the axle of rotation of the spinning body is substan- 'tially excluded.

For further correcting the influence of the varying direction of the course of the ship adjusting means similar to those described and controlled by frame 35 could be used. The effect would also be essentially the same if instead of frame 16 frame 35 would be used for controlling the adjusting means because the' displacement of plate 14 with relation to frame 16 causes avariation of the inclination of the revoluble axle 36 of the spinning body towards the horizontal plane 14.

Fig. 5 shows a modification where correcting means are provided controlled as well by frame 35 as by' frame 16. The operation of such controlling means is substantially the same as that described with reference to Fig. 1, where only frame 16 controls the operation of the actuating means for platform 14. The pole piece connected to frame 35 is designated 310', the opposite pole piece 340, and the fluid resistance 330.

Besides the alteration of the direction of the course of the ship the invariability of the direction of the axis of rotation of the spinning body is disturbed by the friction of said axis in its bea'ringsand by the friction of the rotatable frames 16 and 35 in their bearings. As a means for overcoming this friction I have shown-

rotatable bearings

19 and 20 for the

pins

17 and 18 carrying frame 16. It is known that theinfluence of the friction is much more considerable if an obj ect is put into movement from the situation of rest. Therefore the influence of'friction is diminished if the bearings of a rotatable body are permanently rotated so that there exists no friction resulting from the starting of the rotatable object. The friction diminishing effect is the completest possible if 00- operating bearings, that is to say bearings belonging to one singleaxle, are rotated n opposite directions, or if same" are only ossphere of cillated so that the influence of friction exerted by the oscillation in one direction is compensated by the influence exerted by the oscillation in the opposite direction. The

influence of friction must be considered also in so far as it is caused by the weight of the I rotating body resting in its bearings.

It is known to those skilled in the art that the spinning bod is practically a body of considerable weig t. Now it is an essential .point in a gyroscope that the rotating masses are arranged symmetricall to the axes of rotation. However the in uence of gravity cannot be excluded by merely distributing the mass of the rotating. elements symmetrically to the axes of rotation if the axes of rotation do not remain in invariable position.

Assuming that the mass connected to the v axle 36 of the spinning body is arranged symmetrically to such axes and to the axis '38 of frame 35 so' that the bearings of the axle 36 are free from tension in axial direction as long as the axle 36 remains in horizontal position, then pressure will be exerted on the bearings of said axle 36 if frame35 is rotated about the axis38. The bearing of the axle 36 in that part of the frame 35' which is inclined toward plate 14 must sustain tension in the direction of the axle 36 resulting from the influence of gravity. In order to secure equal pressure on both bearings of the revoluble axle of the spinning body the upper bearing is formed by the spring actuated parts 41 connected to frame 35. The springs 43 take up one part of the weight of'the spinning body and of its axle in a position inclined towards the horizontal plane. In this way the disturbing influence of the inclination of the revoluble axle of the spinning body towards the horizontal plane is diminished or entirely eliminated.

.The springs 43 are so regulated that the weight of the spinning body is uniformly distributed on the hearings on' bot-h sides of the spinninglbody so that an actual movement of axle 36 in an axial direction does not take place even if the frame 35 assumes a'considerable inclination toward the horizontal plane. The springs 43 are intended to be operated only in the case where the revoluble axle of the spinning body is not kept. horizontal.

This is'the case under preferred conditions where the said axle is adjusted so as to be arallel to the axis of the earth. When this is done the variation of the inclination of the rotatable axis is kept within certain limits provided that the ship or other carrier of the gyrosco e permanently remains either on the nort ern' or on the southern hemlthe earth. For this reason the conical step bearing on the right and the ball bearing on the left in the embodiment shown in Figs. 1 and 2 of the drawingsare made to be adapted to resist displacement of the axle invariable inclination ofjthe axle of the spinto resist left hand displacement.

If an alteration of the inclination of the revoluble axle of the spinning body towards the horizontal plane takes place, the iron core 52 immediately readjusts the carrying frame 35 of said axle. Namely under normal conditions the

metallic rods

55 and 56 connected to frame 35 are immersed at the same time into the mercury filling 54 of the receptacle 53. Therefore under normal conditions the current circuits of both the

coils

49 and 50 are closed securing an invariable position of the iron core 52. If however by some external influence the frame 35 which carries the axle 36 of the spinning body alters its inclination .towardsthe horizontal'plane then the one rod, say 55, is immersed deeper into the mercury,the level of which always remains in a horizontal plane, whereas the second rod, say 56, is elevated, above the level of the mercury 54 so that the current circuit through the one coil, say 49, remains closed, whereas the current circuit through the other coil, say 50, is interrupted. The consequence of such interrupting of the current circuit of the one coil is a shifting of the iron core 52 in such a direction that the weight of the frame 35 on that side of .the axle 38 which had been elevated. is increased. This producing a tendency to depress the elevated part of the frame 35 and to bring it back to its normal position in which the two

rods

55 and 56 are immersed at the same time into the mercury 54. The same-effect would beobtained if the coils were not fixed to frame 35 and the iron core shiftable within the cores but if instead the coils would be fixed to frame 16 and the core in substan-. tially vertical osition fixed to frame 35. In this instance t e tendency of the coils to shift the iron. core would result in a pull on frame 35. 1

' The device above deseribed for securing ning body toward the horizontal plane is sub stantiallyintended to secure a position of the axle parallel to the horizon, the variation of the'inclination in this case being very small. Theyielding means comprising springs 43 are in this instance substantially inoperative so that the effectiveness of the ap aratus is not interrupted by the fact that t e conical step bearing 44 on the right and the ball bearing 40 on the left of the axles 36 only prevent displacement of said shaft and rotatable parts toward the right. If it-is intended to keep the axle of the spinning body in a position different from'that parallel to the horizon, for instance, in a position par-' allel to the axis of the earth; the mercury contained in the vessel 53 may .be poured out or the

rods

55 and 56 may be taken off gyroscope it is to forms theessential condition for the practical use of a gyroscope is effected by two electromotors for currents with more than one phase comprising. the inducing bodies 47 firmly mounted on the frame 35 and the induced bodies 48 mourited on the axle 36. It has been-found that the use of currentinduced bodies mounted on the axle 36 and bein separated from the spinning body 37 is 0 high practical value if suc induced bodies form part of an electromotor for currents with more than one'phase, es ecially if the induced bodies 48 are encircle by the inducing bodies 47 y While I have described in the foregoing specification a gyroscope which is provided with a number of improvements adapted to diminish the disturbing influences of the movement of a shi or, other carrier of the e' understoodthat it is not necessary that all the said im rovements are used in combination with eac other and that at the same time without departing from the spirit and the scope of my invention numerous changes may be made with relation to the details of construction.

Having now particularly described and ascertained the nature of my invention, and in what mannerthe same is to be performed, I declare that what I claim is:

1. A gyroscope comprising an arbitrary number of spinning bodies, a rotatable frame, an axle supporting said spinning bodies and. revolubly mounted in said rotatable frame, pivots for said frame, supporting means for said pivots and frame, means for rotating said axle with'said spinning body, at least adapted to be displaced with relation to the carrying axle by centrifugal force.

2. A gyroscope comprising an arbitrary number of spinning bo( ies, an axle supportbody ing same, a rotatable frame, said axle revolubly mounted in said rotatable frame, pivots for said frame, supporting means for said pivots and frame, means for rotating said.

axle with said spinning body, at least one part of the mass of the spinning body adapted to be displaced with relation to the carrying axle by centrifugal force, and means for securing permanent connection between the axle of rotation ofthe spinning body andth displaceable parts of its mass.

3. A gyroscope comprisin at least one spinning body provided wit at least one cavity, lling material in said cavity adapted to be displacedon rotation-of the splnning body, an'axle su orting said spinning bod said axle revolubly mounted in a rotatab e frame and supporting means "forsaid last named frame, I

'41 A gyroscope comprisin spinning body provided wit 'at least one 7 cavity forming a ring, filling material in said 65 The rotation of the spinning body which cavity adapted to be displaced on rotation 130 at least one at least one bly mounted in a rotatable frame and supporting means for said last named frame.

6. A gyroscope comprising at least one spinning body'provided with at least one cavity forming a ring, said cavity containing mercury, an axle supporting said spinning body or bodies, said axle revolublymounted in a rotatable frame and supporting means for said last named frame.

7. A gyroscope comprisin at least one spinning body provided with at least one cavity forming a ring, filling material in said cavity adapted to be displaced on rotation of the spinning body, an axle supportin said spinning body, said axle bein arrange concentrically to said ring and substantially perpendicular to the plane of the ring and revolubly mounted in a rotatable frame and supporting means for said last named frame.

8. A gyroscope comprising an axle revolubly mounted in a rotatable frame, pivots for said frame and means for supporting said pivots, a heavy ring-shaped body encircling said axle and in connection with same the connecting member adapted to allow limited freedom of movement of said axle and ring with relation to each other by centrifugal force and power-actuated means for rotating said axle and heavy ring.

9. Ag 'roscope comprising at least one spinning body, an axle supporting said spinning body, said axle revolubly mounted in a rotatable frame, supporting means for said last named frame, bearings for said axle in said rotatable frame and means on opposite sides of said spinning body adapted to relieve the pressure of the spinning body operative in axial direction.

10. A gyroscope comprising at least one spinning body, an axlesupporting said spinning body, said axle revolubly mounted in a rotatable frame, supporting means for said last named frame, bearings for said axle in said rotatable frame and spring actuated means on one side of said spinning body adapted to relieve the pressure of the spinning body operative in axial direction and means on the other sideof the spinning body likewise adapted to relieve the pressure of the spinning body operative in axial direction.

11. A gyroscope comprising at least one spinning body, an ax e supporting said spinning body, said axle revolubly mounted in a rotatable frame, su )porting meansfor said last named frame, earings for said. axle in said rotatable frame, sprin actuated means co-acting with the axle of 51s spinning body on opposite sides of said spinning body adapted to relieve the pressure of the spinning body operative in axial direction.

12. A-gyroscope comprising atleast one spinning body, an axle sup orting said spinning body, said axle revolu ly mounted in a rotatable frame, supporting means for said last named frame, bearings for said axle in said rotatable frame co-acting with said axle on opposite sides of the spinning body mounted on the axle, the bearing surfaces of said bearing beings turned towards the sameside, so as to allow distribution of the axial pressure on bearings on opposite sides of .the spinning body. v

13. A gyroscope comprising at least one spinning body, an axle supporting Said.-j spin ning body, said axle revolubly mounted ina rotatable frame, supporting meansfor said last named frame, bearings for said 'axle in said rotatable frame on opposite sides of the. spinning body, spring actuated means inoperative connection with said bearings adapted to relieve the pressureof the spinning body in axial direction.

14. A gyroscope comprising at least one spinning body, an axle supporting said spinning body, said axle revolubly mounted in a rotatable frame, supporting means" for said last named frame, automatical adjusting means adapted to secure substantially invariableposition of the axes of rotation, of said frame and spinning body with relation'to the support of said frame and spinning body.

' 15. A gyroscope comprising at least one spinning body, an axle supporting said spinning body, a support, rotatable frames between said support and said axle, the axle of the spinning body being revolubly mounted in one of said frames, a further support carrying said first named support, a rotatable connection between said two supports, and power actuated means for rotating said frame carrying support. I

16. A gyroscope comprising at least'one spinning body, an axle supporting said spinning body, a support, rotatable frames between said support and said axle, the axle of the spinning body being revolubly mounted in one of said frames, a further support carrying said first named support, a rotatable connection between saidtwo supports,

"ower actuated means for rotating said frame carrying support and automatical adjusting means adapted to control sa d power actuated means, said automatical adjusting means operated by the frame which is directly carried by the frame carrying support.

17. A gyroscope comprising at least one spinning body, n axle supporting said spin-' ning body, a support, rotatable frames between said support and said axle, the axle of the spiriningbody being revolubly mount ed in one of said frames, a'furth'er support carrying saidfirst named support, a rotatable connection between said two supports,

ower actuated means for rotating said rame carrying support and automatical adjusting means adapted to control said power actuated'means, said automatical adjusting means operated by the frame which carries the'spinning body and it's revoluble axle, said adjusting means being operated by the spinning body carrying frame.

18. A gyroscope comprising at least one spinning body, an axle supporting said spinning body, a support, rotatable frames between said support and said axle, the axle of the spinning body being revolubly mounted in one of said frames, a further support tween said support and said axle, the axle of the spinning ody being revolubly mounted in one of said frames, automatical adjusting means adapted to adjust said last named frame so 'as to secure an invariable inclination of the same.

20. A gyroscope comprising at least one spinning body, an axle supporting said spinning body, a support, rotatable frames between said su port and said axle, the axle of the spinning ody being revolubly mounted in one of said frames, a horizontal platform, current controlling means forming a bridge between said frame and said platform, automatical adjusting means operated by such current and adapted to adjust said spinning body carrying frame so as to secure an invariable inclination of thesame.

- 21. A gyroscope comprising at least one spinning body, an axle supporting said spinning body, a support, rotatable frames be-' tween said su port and said axle, the axle of the spinning body being revolubly mounted in one of said frames, a weight in adjustable connection with said axle carrying frame and automatical means for adjusting said weight so as to secure an invariableinclination of saidcarrying frame.

22. A oscope comprising'at least on spinning ody, an axle supporting said spin-.

ning body, a support, rotatable frames between said su port and said axle, the axle of the spinning ody being revolubly mounted in one of said frames, a weight in adjustable connection with said axle carrying frame, a coil connected to said frame and adapted to be energized by electric current, said coil in operative connection with said weight, a hori- -'zontal platform, current controlling means tween said support and said axle, the axle of the spinning body being revolubly mount- 'ed in one of said frames, rotatable bearings carrying said rotatable frames and axle of the spinning body, said rotatable bearings being arranged in pairs in axial alinement, means adapted to rotate one bearing of each pair in one direction and the other in the opposite direction.

25. A oscope comprising at least one spinning ody, an axle supporting said spinning body, a support, rotatable frames be tween said support and said axle, the axle of the spinning body'being revolubly mounted in one of said frames, a carrier for said support, power actuated means in connection with said carrier adapted to rigidly hold the carrier in a predetermined position, parallel to the horizontal plane.

26. A gyroscope comprising at least one spinning body, an axle supporting said spinning body, a support, rotatable frame connection between said support and said axle including a carrying frame in which the axle of the spinnin body is revolubly mounted and a rotatab e platform in which the c said support for the rotatable frames of thegyroscope is mounted. i

27. A gyroscope comprising at least one means for rotating said spinning body and its revoluble axle, said current actuated means forming an electromotor for currents with more than one base and comprising current inducing bo ies, mounted on the spinning body carrying frame and current induced bodies different from the s inning body and mounted on the axle of t e spinning body. A

28. A gyroscope comprising-at least one spinning body, an axle supporting said spinning body, a support,- rotatable frames between said support and said axle, the axle of more than one phase and comprising current the spinning body being revolubly mounted i body and encircled by said current inducing 10 in one of said frames, current actuated means means. for rotating said spinning body and its rev- In testimony whereof I have signed this oluble axle, said current actuated means specification in the presence of two subscribforming an electromotor for currents with ing witnesses.

NARCISS ACH.

inducing bodies, mounted on the spinning Witnesses: -body carrymg frame and current induced JEAN GRUND, bodies mounted on the axle of the spinning CARL GRUND.