US2641132A

US2641132A - Gyroscopic rotor frame

Info

Publication number: US2641132A
Application number: US50801A
Authority: US
Inventors: Clare E Barkalow
Original assignee: Sperry Corp
Current assignee: Sperry Corp
Priority date: 1948-09-23
Filing date: 1948-09-23
Publication date: 1953-06-09
Anticipated expiration: 1970-06-09

Description

June 9, 1953 ;n E, BARKALOW 2,641,132

GYROSCOPIC ROTOR FRAME Filed Sept. 23, 1948 INVENTOR Cum? E. BHR/m/.ow

f@ 73 j .62 BY i gli z ATTORQY Patented June 9, 1953 GYROSCOPIC KOTOR FRAME Clare E. Barkalow, Huntington, N. Y., assignor to The Sperry Corporation, a corporation of Delaware Application September 23, 1948, Serial No. 50,801

3 Claims.

This invention relates to frames for supporting gyroscopic rotors.

One of the features of the invention resides in the provision oi a structure of this character comprising a closed thin hollow spherical metallic shell formed of two interiitting hemispherical parts. Heretofore, full or partial shells of this geometrical shape have been employed to provide a covering for the main rotor supporting structural frame. Such coverings provided symmetrical surfaces adapted to carry indicia. The coverings were suitably fastened to the exterior of the main rotor supporting structure. In the present instance, the shell per se provides the structural frame for supporting the gyroscopic rotor. A shell of this type has the structural advantages over known closed types of frames of lighter weight, of not being subject to uneven internal stresses with changes in air pressure exteriorly of the shell, and of being similarly symmetrical relative to the spin axis of the rotor that it supports as well as its precession axis. In addition to the above, the closed shell per se provides a structural member of suincient strength and rigidity to support a gyroscopic rotor.

A further feature of the invention resides in the rotor frame structure combination of a thin spherical shell and a spaced pair of oppositely disposed bearing mountings connected to the respective hemispherical parts to project radially Within the shell.

Another feature of the invention resides in the provision of a thin hollow spherical metallic shell having two hemispherical parts with interitting portions connected thereto providing a circum* ferential band of greater thickness than the shell.

Other features, advantages and structural details of the invention will be apparent from the following description when read in connection with the accompanying drawing, wherein,

Fig. 1 is a sectional view of a rotor frame constructed in accordance with the present invention taken on line I-I, in Fig. 2;

Fig, 2 is an end elevation of the improved frame;

Fig. 3 is an enlarged detail sectional view of one of the electrical lead connections on the frame, and

Fig. 4 is a sectional View showing the connection between one of the trunnions and the spherical frame.

With reference to the drawing, the improved rotor frame is shown to include a thin spherical shell indicated generally at I0 formed of two substantially hemispherical parts II and I2 that are joined by a suitable screw threaded connection.

The thickness of the frame at the connection of the parts I I and I2 is heavier than the main body of the shell to provide a circumferential band or ring I3 thereon to which a pair of oppositely disposed trunnions I4 and I5 are suitably connected exteriorly of the shell. As shown in Fig. 1, the trunnions I4 and I5 engage suitable bearings in a gimbal ring such as shown in part at I6. The intertting portions of the respective hemispherical shells II and I2 form the ring or circumferential band i3 of the frame. Band I 3 is of greater thickness than the main body of the shell to provide for the connection between the parts I I and I2 as well as to lprovide an area suiiciently strong to connect the trunnions thereto. As shown in Fig. Ll, trunnion I4 is provided with Aa projecting part I'I that fits an opening in the part of ring I3 included in hemispherical shell II. The trunnions are mounted in such a manner that the connection is permanent and air-tight.

The frame further includes a spaced pair of oppositely disposed bearing mountings indicated at I 8 and I9 that project radially within the shell I0 and include axial openings that extend substantially through the shell. Shell IIJ is preferably rnade of a metal such as steel to provide sufficient strength and rigidity to support a gyroscopic rotor therein. As the shell is thin, the Weight of the same is lighter than conventional type closed or open frames made of relatively thick metal. or reinforced to obtain necessary structural rigidity which increases the weight of the same. In the improved frame, no internal or external ribbing or reenforcing is necessary due to the inherent rigidity of a sphere. As the weight of the improved frame is decreased over known type of frames for a gyroscope of the character shown, the quality of merit of the device, or the ratio of the angular momentum of the gyroscopic rotor to the weight of the rotor plus the weight of the frame supporting the same, is materially increased.

In the improved frame shown, the mountings I8 and I9 may be formed as a part of the shell by connecting the parts by a copper brazing operation. This secures the noted parts with the openings in the shell provided for the mountings arranged in concentric relation with the axial openings in the mountings for the bearings. The bearing mountings I8 and I9 project radially Within the shell I 0 to support the gyroscopic rotor to spin about a diametric axis within the shell with the center of gravity of the rotor coincident with thegeometrical center of the shell. Asshown in Fig. 1, the tubular bearing mount@ Known types of frames are ribbed ings I8, I9 are of greater thickness than the thickness of the thin spherical shell I0.

The gyroscopic rotor of the frame structure is indicated at 2D. This element is rotatably supported in the shell with its center of gravity at the center of the spherical shell. The gyroscopic rotor mounted in the improved frame is provided with an axially open shaft 2| that engages the spaced

ball bearings

22 and 23 in the respective mountings I8 and I9. The axial spacing between the bearings is maintained constant and uneffected by temperature changes during operation by means of a shaft mounting arrangement such as particularly described and claimed in U. S. Letters Patent No. 2,353,139, dated July l1, 1944, to Lennox F. Beach. This construction includes an axially positioned strut 24 of approximately the same length as the shaft 2l made of a material having approximately the same temperature coeihcient of expansion as the shaft. The means connecting the strut 24 and respective mountings IS and I8 is shown in the present instance to include the threaded

pins

25, 26 and a pair of axially adjustable pieces 2l, 28 that in the arrangement shown are connected to the respective mountings by threaded engagement. The outer races 2S and 30 for

bearings

23 and 22 respectively are xedly held in the respective pieces 2l and 28 by means of lock nuts SI and 32. Locking nuts 33 and 34 are provided for the

respective pins

25 and 26.

Further lock nuts

35 and 36 are utilized to hold the

adjustable pieces

21 and 28 in the proper positions in the mountings IB and I8 so that the

bearings

23 and 22 are located within the shell at equal axial distances from the center of the shell to properly position the gyroscopic rotor 2D. In accordance with the teachings of the hereinbefore noted patent, the

pins

25 and 28 are initially adjusted to place the strut 24 under compression. In the finished assembly of the frame, the axial openings in the bearing mountings I9 and I8 are closed by means such as the threaded plugs indicated at 31 and 38.

ln accordance with the invention, the gyroscopic rotor 2Q of the improved frame is spun by an electric motor having a pair of corresponding electrical rotors 39 and 40 included in the gyroscopic rotor and similar or corresponding electric stators 4I and 42 that are rixedly mounted on extending portions of the respective bearing niountings I9 and I8. The motor shown is oi the polyphase induction type having separate three phase wound stators and separate electric rotors of identical size and shape. The electrical rotors 39 and 40 are mounted in a flanged portion of the gyroscopic rotor 28, the arrangement being such that the same are located at equal distances along the spin axis of the gyroscopic rotor 2G to either' side of the geometrical center of the shell I5. The electrical stators 4I and 42 are similarly mounted on the bearing mountings I9 and I8, respectively, so the same are located at equal distances along the spin axis to either side of the center of the improved frame.

Electrical energy from a suitable source of alternating current (not shown) is supplied to the stators of the electric motor within the frame by way of three suitable leads 43. These leads, as shown in Figs. 2 and 3, enter the shell through individual plugs 44 that are shown in cylindrical form. The plugs 44 enter suitable openings in the shell I@ and may be silver soldered or otherwiseconnected to the shell. The lead in wires 43 at the plugs 44 are made of a glass sealing alloy as is the tubular insert 45 in the plugs so that a glass seal 46 may be provided as shown to connect the parts and insure an air-tight t. An insulating member 41 serves the purpose of holding the Wires 43 rmly in the plugs 44. Plates 48 formed as part of the plugs 44 are also provided to anchor the leads exteriorly of the plugs.

Balancing means for the improved frame is provided in the form of a plurality of symmetrically arranged threaded U-shape lugs suitably mounted on the exterior of the shell I0 as indicated at 49. Each of the lugs 49 engages a suitable adjustable balancing screw. Only six of the provided eight balancing screws appear in Fig. 2 of the drawing.

In the finished unit the threaded connections between the parts I I and I2 and the plugs 3'I and 38 are sealed, as for example, with soft solder. The air is then evacuated from the closed frame by suitable external suction applying means (not shown) through a tube formed as a part of a threaded nipple 52 xedly connected and sealed to the shell I8. When the proper vacuum is attained the tube 5i is pinched to form an air-tight joint as shown in Fig. 2. The finished frame is air-tight or hermetically closed.

Since many changes could be made in the above construction and many apparently Widely different embodiments of this invention could be made Without departure from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A gyroscopic rotor frame composed of a thin hollow spherical metallic shell having two liemispherical parts with interfltting portions connected thereto providing a circumferential band of greater thickness than the shell, a spaced pair of oppositely disposed bearing mountings connected to the respective hemispherical parts to project radially Within the shell, and a gyroscopic rotor supported within said shell by said bearing mountings to spin about an axis concentric with the axis of the circumferential band.

2. A gyroscopic rotor frame composed of a thin hollow spherical metallic shell having two hemispherical parts with interiitting portions connected thereto providing a circumferential band of greater thickness than the shell, a pair of exterior oppositely disposed trunnions mounted on the band portion of the shell, a. spaced pair of oppositely disposed bearing mountings connected to the respective hemispherical parts to project radially within the shell, and a gyrcscopic rotor supported within said shell by said bearing mountings to spin about an axis normal to the axis defined by said trunnions.

3. A gyroscopic rotor frame composed of a thin'hollow spherical metallic shell having two hemispherical parts wyith interiitting portions connected thereto providing a circumferential band of greater thickness than the shell, a spaced pair of oppositely disposed tubular bearing mountings of greater thickness than the shell connected to the respective hemispherical parts to project radially within the shell, and a gyroscopic rotor supported within said shell by said bearing mountings to spin about an axis concentric with the axis of the circumferential band.

CLARE E. BARKALOW. (Referenc on following page) Number Number Name Date Boykow June 17, 1930 Davis Aug. 19, 1930 Gillmor Jan. 8, 1935 Bennett Apr. 9, 1935 Smith Oct. 18, 1938 Beach July 11, 1944 Bousky Dec. 31, 1946 FOREIGN PATENTS Country Date Great Britain May 6, 1926