US2325530A - Fluid driven gyroscope - Google Patents

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July 27, 1943. F. w. MEREDITH 2,325,530

. FLUID DRIVEN GYROSCOPE Filed Jan. 15, 1945 Z2 ran??? Patented July 27, 1943 assignor to S. Smith & Sons (Motor Accessories) Limited, London, England, a British company Application January 15, 1943, Serial No. 472,525 In Great Britain November 21, 1941 11 Claims. (01.253-56 This invention relates. to fluid driven gyroscopes and is directed towards. increasing the. ef ficiency thereof.

Normally, the periphery of the gyroscope rotor is provided with a surround, usually, a part of the rotor casing, and "the driving fluid circulates in an annular space between the surround and the periphery of the rotorfi The width of this space between the surround and periphery in a plane containing the rotor axis, is usually uniform across the peripheral surface; that is to say, the surround is uniformly spaced from the rotor periphery across the axial width thereof.

The working fluid entersthe central part of the surround, engages the rotor buckets and then spreads out laterally in an. axial direction. over the rotor periphery. In order to increase, the driving torque it is desirable to increase. the viscous resistance of the fluid at the centre where the fluid is rotating at'a greater speed than. the rotor. This can be done by making the separation between the surround and. the rotor periphery small. This, however, results in an increase of viscous resistance in the region of the lateral fiow over the rotor periphery, where the fluid is circulating at alesser speed than the rotor and therefore causing drag on the, rotor. Consequently, in determining the separationbetween the surround and the rotor periphery a compromise has previously been made between increased torque and increased. drag. The object of the present invention is to overcome this diihculty. 7

According to the present invention, afl'uid driven gyroscope having a surround encircling;

the periphery of the gyroscope rotor is so constructed as to provide a space between theseparts which is less at the centre of the periphery'than at its sides, which surround is provided with a number of air passages directed in an inclined manner on to said periphery. The separation increases gradually towards the sides to ensure streamline flow and the avoidance ofturbulence.

- periphery of the rotoris roughened overits. central portion, for example by knurling.

In one construction in accordance, withth invention the periphery of the rotor is curved so that the maximumradius. of. therotor isat the centre and, the minimum-at theside s. A band runninground the central partof the. periphery,

or the part of maximum radius is knurled in the same wayas the. edge of a knob is knurled to enable a finger grip to be obtained, but the knurling is made rather finer and is of a crisscross character.

The surround is provided with a cylindrical inner surface and a number of jet passages are arranged to extend through the surround with their axes lying in a central transverse plane and each inclined to a radius of the gyroscope whereby a ring of driving jets is formed, each preferably directed on to the periphery of the rotor. These jets communicate with an annular air chamber formed between an outer wall of a casing and the surround, which annular chamanother, form of the casing.

Referring to Figure 1, the numeral i0 represents the gyroscope rotor which is encircled by a surround ll having a number of jet passages i2 inclined to the radius of the rotor. An outer casing I3 is spaced away fromv the surround so as to provide an annular air chamber id. The annular air chamberis provided with a suitable air inlet passage 5' in' the wall of the casing.

As will be seen from Figure 2, the casing is shown in Figure 1, and are rendered fluid-tight by'a spigot joint i9 and'packing ring 26 formed between these parts' The spindle 2! of the rotor is supported by ball bearings 22; the outer race 23 of which is carried by the casing. The races 23',are provided with axial passages 24 through which the spent air from the driving jets may escape from the casing. It may, however, be preferableto plug these passages 24 and provide alternative passagesin. the casing which operate/as. anti-topple or precession modifying jets in known manner. the inner surface 25 of. the surround is cylindri- It will be. noted that cal in shape, whereas the periphery 26 of the rotor is curved, thereby providing a space between the periphery and said inner surface which gradually increases from the central portion of the through the passages 12 is obtained by means which maintain the pressure in the annulus l i higher than in the casing. The arrangement shown in Figure 3 differs from that of Figure 2 in that the surround H is, formed separately] rotor so as to provide an annular space between them which is of less depth around the central circumference of the periphery than at the sides thereof, the depth of said annular space being uniform in any given radial plane throughout its full circular extent.

4. A fluid driven gyroscope comprising a rotor, a surround encircling the periphery of the rotor and having a cylindrical inner surface, which 10 surround is provided with passages adapted to direct pressure fluid on to said periphery in an appropriate direction to drive the rotor, the periphery of whichrotor is curved across its width from the casing part it and is channel-shaped in cross-section having its flanges 23 clamped between the two casing parts. i

In both of the illustrated the distance between the surround and the .of an inch. Consequently, the high speed Iof the air issuing from the passages around the periphery and the resultant high viscous, resistance gives a large driving torque to the knurled band. The distance of the surface of the surround'from the rotor periphery increases to fifty-thousands of an inch at the sides of the rotor, which results in a reduction'in the viscous drag. in order to improve the streamlined flow towards the side of the rotor it will be noted that the sides of the casing part are conical in shape.

In the above constructions, the efflciency is found to be high and at the same'time the conto provide an annular space between them which isof less depth around a central radial plane of said rotor than at parallel radial planes spaced from said central planathe depth of said annular space being uniform in any given radial plane throughout its full circular extent.

2. A'fluid driven gyroscope comprising a rotor, a surround encircling the periphery of the rotor, said surround containing passages adapted to direct fluid on to said periphery in an appropriate direction to drive the rotor, means for causing flow of fluid insaid passages'toward said rotor, said periphery and surround being shaped to provide an annular space between them which increases gradually from a centralradial plane of said rotor to its sides, the depth of said ann'ular space'being uniformiin any given radial plane throughout its full "circular extent.

A fluid driven gyroscope comprising a rotor; a surround encircling the periphery of the rotor said surround containing passages adapted to direct fluid on to said periphery'in'an appropriate direction to drive the rotor, means for causing flow of fluid in said passages toward said rotor, one ofj which above recited members of the yroscope hasa cylindrical surface and the :other a curved surface across the width of the constructions,

central knurled band of the rotor and thus between the mouths of the passages l2 and the knurled band, is about eight-thousandths so as to-provide an annular space between it and the surround which is of less depth around the central circumference of the periphery than at the sides, the depth of said annular space being uniform in any given radial plane throughout its full circular extent.

5. A fluid driven gyroscope comprising a rotor the periphery of which is provided with a central circumferential" band roughened as by knurling, a surround encircling the periphery of the rotor and containing passages adapted to direct fluid under pressure on to said periphery in an appropriate direction to drive the rotor, said periphery and surround being shaped to provide between them a space which is less around the central circumference of the periphery than its sides. 7 r

6. An air driven gyroscope comprising a rotor, a'surround encircling the periphery of the rotor and formed witha number of pressure air passages each directed in an inclined manner to the adjacent radius of thegyroscope, which periphery and surround are shaped to'provide between them an annular space which is of less depth around a certain central radial plane of said rotor than at parallel radial planes spaced from said central plane, the depth of said annular space being uniform in any given radial plane throughout its full circular extent.

'7. An airdriven gyroscope comprising a rotor, a surround encircling the periphery of the rotor and having-a number of air passages formed therein and each inclined to the adjacent radius of the rotor, a casing encircling said surround and spaced away from it to provide an annular chamber, an air conduit communicating with said chamber, said periphery and surround being shaped to provide an annular space between them which is of less depth around a central circumference of the periphery than at the sides thereof, the depth of said annular space being uniform in any given radial plane throughout its full circular extent, and means forthe educticn of air from said latter space.

8. A fluid driven gyroscope comprising a rotor, an outercasing encircling said rotor, a surround formedintegrally with said casing as to provide an' annular air chamber, an air conduit communicating with said chamber, said surround being pr'ovidedwith a number of air passages, each inclined to the adjacent radius of the rotor, the periphery of the rotor and the surround being shaped to provide between them an annular space which is of less depth around the central circumference of the periphery than at the sides thereof, the depth of said annular space being uniform in any given radial plane throughout its full circular extent,'and means for the eduction'of air from said latter space.

An air driven gyroscope comprising a rotor,

a surround encircling the periphery of the rotor and containing air passages adapted to direct air in an appropriate direction on to said periphand means communicating with said space for i the eduction of air therefrom.

10. A fluid driven gyroscope comprising a rotor, a two-part casing around the rotor, a surround formed integrally with one of the parts of the casing so as to provide an annular chamber encircling the periphery of the rotor, which surround contains air passages adapted to direct air in an appropriate direction on to said periphery to drive the rotor, an air conduit communicating with said annular chamber, said periphery and surround being so shaped as to provide an annular space between them which is of less depth around the central circumference 11. A fluid driven gyroscope comprising a rotor,

a two-part casing around the rotor, a surround encircling a periphery of the rotor and clamped between the two parts of the casing so as to provide an annular space between it and the casing, said surround being provided with a number of air passages, each inclined to the adjacent radius of the rotor, an'air conduit communicating with said annular spacasaid periphery of the rotor and the surround being so shaped as to provide an annular space between them which is of less depth around the central circumference of the periphery than at the sides thereof, the depth of said annular space being uniform in any given radial plane throughout its full circular extent, and. another air conduit communicating with this latter space for the eduction of air therefrom.

FREDERICK WILLIAM MEREDITH.

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