US2994195A

US2994195A - Jet reaction prime mover

Info

Publication number: US2994195A
Application number: US803724A
Authority: US
Inventors: James M Carswell
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-04-02
Filing date: 1959-04-02
Publication date: 1961-08-01
Anticipated expiration: 1978-08-01

Description

1961 .1. M. CARS-WELL 2,994,195

JET REACTION PRIME MOVER Filed April 2, 1959 6 Sheets-Sheet 1 l NV ENTOR FLUID M0T0Rj8 E y Aug. 1, 1961 J. M. CARSWELL 2,994,195

JET REACTION PRIME MOVER Filed April 2, 1959 6 Sheets-Sheet 2 I: THE Q INVENTOR Jfi/Wf M. CAR/VELL 1951 J. M. CARSWELL 2,994,195

JET REACTION PRIME MOVER Filed April 2, 1959 6 Sheets-Sheet 3 INVENTOR J/IM55 M. 41% h fLL Y/QZM 1961 J. M. CARSWELL 2,994,195,,

JET REACTION PRIME MOVER Filed April 2, 1959 e SheetsSh'eet '4-= INVENTOR JAMES M. 04/95 h/L 4 Aug- 1, 1961 J. M. CARSWELL JET REACTION PRIME MOVER med April 2, 1959 6 Sheets-Sheet 5 INVENTD R Aug, 1, 1961 J. M. CARSWELL 2,994,195

JET REACTION PRIME MOVER Filed April 2, 1959 e Sheets-Sheet e INVENTDR 2,994,195 JET REACTION PR'IlVIE MOVER James M. Carswell, Andover, Mass. (6202 Gould Ave., Seattle 8, Wash.) Filed Apr. 2, 1959, Ser. No. 803,724 15 Claims. (Cl. 60-3935) This invention relates to improvements in jet reaction prime movers of the type disclosed in my United States Patent No. 2,637,166, granted May 5, 1953, in which the reactions of high velocity jets are utilized to effect rotation of a rotor to provide output shaft power.

In order to provide a practical device of the above nature, the tip speed of the rotor must be high in order to achieve a reasonable value of propulsion efiiciency, and consequently the rotor must operate in a partial vacuum as otherwise the high speed requirement of the rotor tip would result in inordinate drag losses due to the movement of the rotor through the atmosphere.

It is the object of this invention to provide a jet re action prime mover which will itself support a partial vacuum in which the rotor will rotate and will also of itself effect removal of the products of combustion from the partial vacuum to the atmosphere, thereby enabling a device of this type to be constructed in a simple practical form to achieve an extremely high operating efliciency and consequently an extremely high power to weight ratio.

Another important object is to provide a rotor construction which will enable the desired high tip speeds to be safely achieved without detriment to the rotor. In this connection it is a further important object to provide a novel combustion chamber at each tip of the rotor which will provide a large mass flow to achieve a high power output from the rotor without materially reducing the high centrifugal stress capabilities of the rotor.

Again it is a further object to enable the fuel and combustion supporting air to be delivered to the combustion chambers in a manner which will place no limitation on the high tip velocities and stresses to which the rotor can be subjected.

A further important object is to provide an eificient cooling system which will preclude rotor temperatures from reaching any point where they would deleteriously affect the material from which the rotor is constructed.

Still another important object is to provide an efficient means of starting the device.

The principal feature of the invention resides in rotatably supporting a rotor within a casing and supersonically diffusing the products of combustion discharged from combustion chambers disposed at the tips of the rotor from the casing into the atmosphere to utilize the efliux of the products of combustion to sustain a partial vacuum within the casing which is the prerequisite of steady state operation, and at the same time to achieve such efiiux from a relatively low pressure area within the casing to a relatively high pressure area constituted by the atmosphere outside the casing.

Another important feature resides in forming the rotor as a novel slotted blade element to provide a crosssectional area along the axis of the blade which smoothly and continuously decreases outward from the axis of the blade rotation.

Also it is an important feature that the combustion chamber and nozzle formed at each tip of the blade be defined by walls having the general form of a catenary as described in the aforesaid patent, and also that the outer wall have a variable thickness varying from a minimum value at the apex thereof to some greater value adjacent to the bases thereof to provide for adequate mass flow thereby achieving high output power.

nited States atent O f 2,994,195 Patented Aug. 1, 1961 Another important feature resides in forming the rotor as a blade having a plane of symmetry normal to its axis of rotation and also to have an identical but opposite configuration on opposite sides of the axis of rotation with the combustion chamber at one end of the blade or rotor tip having a discharge nozzle symmetrically dispose-d with respect to the plane of symmetry and opening at one side of the blade to direct products of combustion tangentially of the rotational path of the blade and the combustion chamber at the other end of the blade or rotor tip being similarly constructed but opening at the opposite side of the blade, the combustion chambers being fed by fuel and air passage systems lying symmetrically on opposite sides of the plane of symmetry.

In this connection it is a feature to feed each combustion chamber by means of a pair of identical symmetrically disposed air passages extending longitudinally of the blade leading from the hub of the rotor at opposite sides of the plane of symmetry to the chamber, and associating with each air passage a fuel passage system comprising a series of fuel passages extending longitudinally of the blade and connected in parallel and lying beneath the air passage at the rotor hub and encircling or wrapping the air passage adjacent the combustion chamber to effect cooling thereof.

Another important feature resides in providing an elliptical entrance to the fuel passages with the entrances extending longitudinally of the fuel passages to minimize stress concentrations at the fuel passage entrances.

Still another important feature resides in leading the fuel from adjacent to the end of the blade or rotor into the combustion chamber through a cooling passage network arranged to cool the combustion chamber and nozzle. In this connection, the combustion chamber and nozzle are defined by a pair of spaced inner and outer loops having their apices contained in and being symmetrical on opposite sides of the plane of symmetry with the loops having a configuration corresponding to the configuration that would be assumed by a flexible membrane hanging in a centrifugal force field, and the cooling passage network comprises distribution ducts extending along the bases of the loops and collecting ducts extending along the apices of the loops, and a system of substantially parallel passages connected in parallel between the distributing and collecting ducts.

Another important feature resides in utilizing the rotor contour in conjunction with contoured shoes or feet provided in aligned support and output shafts which engage the rotor on opposite sides of the plane of symmetry thereof under axial pressure directed toward the rotor to support the rotor therebetween and efiect a mechanical junction between the rotor and shafts for the transmission of output power.

Another important feature resides in delivering the fuel to the fuel passages through these shafts and forming elliptical openings in the shaft shoes or feet corresponding to and mating with the elliptical entrances to the rotor fuel passages.

These and other objects and features of the invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a broken away, part plan, part horizontal sectional view of a jet reaction prime mover embodying the invention;

FIGURE 2 is a part diagrammatic, part mid-vertical sectional view of the device of FIGURE 1;

FIGURE 3 is an enlarged broken away elevational view of the rotor;

- FIGURE 4 is a view similar to FIGURE 3 but broken away to show the air and fuel passages and showing in section the labyrinth seal between the rotor and easing;

FIGURE is a broken away, part perspective, part sectional view, showing in detail the fuel feed between the foot or shoe of the shaft and the rotor, the parts being separated for purposes of illustration.

FIGURES 6 to 13 are transverse vertical sectional views taken on the lines 66 to 13-13 of FIGURE 3;

FIGURE 14 is a perspective view of the rotor;

FIGURE 15 is an enlarged part perspective, part transverse sectional view of one tip of the rotor;

FIGURE 16 is a further part perspective part sec tional view of the rotor tip;

FIGURE 17 is a broken away end elevational view of the rotor;

FIGURE 18 is a broken away front elevational view of one end of the rotor illustrating the combustion chamber and discharge nozzle;

FIGURE 19 is a diagrammatic view illustrating the system of cooling fuel passages utilized at the nozzle and combustion chamber;

FIGURE 20 is a further diagram illustrating the manner of fuel distribution, cooling and collection at the nozzle formation of the combustion chamber at each tip of the rotor;

FIGURE 21 is a diagram illustrating the manner in which the fuel passages leading from the hub of the rotor to the rotor tip are utilized to encircle the air passage to effect air cooling.

With reference particularly to FIGURES 1, 2, 4 and 14, the device constituting the jet reaction prime mover constitutes a rotor 1 illustrated particularly in FIGURE 14, and as shown in FIGURE 2 and FIGURE 4, this rotor is supported between shafts 2 having shoes or feet 3 which have their undersurfaces 4 contoured to bear on a contoured surface portion 5 of the rotor, as seen particularly in FIGURES 4 and 5.

The shafts 2 are axially aligned and the contoured surface portions 5 of the rotor are centered on the axis of the rotor and by applying a suitable inward thrust on the shafts 2 the rotor is firmly gripped therebetween by means of the interengaging contoured surfaces 4 and 5, to support the rotor for rotation about its axis coincident with the shaft axis, and at the same time to provide for the transmission at low torque but high speed of the rotor energy through to the shafts 2 which constitute the output power shaft system of the assembly.

Surrounding the rotor 1 is a casing generally designated at *6 in the form of a pair of dished sections 7 which converge at the periphery of the rotor 1 as indicated at 8, to define a throat formation 9 around the perimeter of the casing. The throat formation 9 opens outwardly into a ring formation 10 which opens to the atmosphere through a series of openings 11 which are adapted to be closed by valves 12 arranged to close upon the atmospheric pressure exceeding pressure within the ring formation 10 with which the throat formation 9 communicates. Preferably the valves 12 may be spring biased by suitable springs 13 to move towards the closed position, the springs being relatively light springs, being required merely sufficient to retain the valves closed when the outer and inner pressures are equal.

As shown in FIGURES 2 and 4, the rotor 1 is provided with an upper and a lower collar 14 fixed thereto concentric with the axis of rotation, each of the collars forming a labyrinth seal as indicated at 15 with the corresponding collar formation 16 provided on the easing, the labyrinth seals permitting a relatively minor air flow through from the atmosphere into the interior of the casing under partial vacuum conditions in the casing.

As will hereinafter be more fully described, air is directed to the rotor 1 inwardly through the casing collar formations 16 and rotor collars 14 into the rotor upon the collars 16 opening to the atmosphere. To close the air inlet suitable caps or covers 17 are slidably mounted on the shafts 2 to move axially thereof into and out of position, closing and opening the air entrances to the systems defined by said casing collars 16. These caps.

or covers 17 may be conveniently operated in any suitable manner, as for instance, by means of hydraulic jacks diagrammatically represented at 18.

Arranged above and below the casing 6 are toroidal tanks 19 which communicate with the interior of the casing through suitable passages 20 controlled by suitable valves 21 diagrammatically illustrated, and these tanks 19 form high vacuum tanks and are connected to suitable vacuum pumps diagrammatically illustrated at 22.

The details of the rotor 1 are shown particularly in FIGURE 3 and its associated sectional views, FIGURES 6 to 13, and in FIGURES 4, 15, 16, 17 and 18. In particular, the rotor as shown in FIGURES 3 and 4 has a plane of symmetry X--X which is normal to the axis of the rotor, and as shown particularly in FIGURE 14, the rotor is of identical but opposite construction on opposite sides of its axis. That is, any point on one half of the rotor is a vectorial counterpart of the corresponding point of the other half of the rotor. It will therefore be understood that in considering the detailed description of one half of the blade, it will apply equally as well to the other half, with the exception, of course, that there is a 180 rotation necessary to bring the corresponding parts of the blade into coincidence.

As will be seen from FIGURES 3 and 4 particularly, the rotor 1 may be considered as a blade element at the outer ends or tips of which are supported combustion chambers 23 and their discharge nozzles 24. According to the invention, the blade portion 1' of the rotor extending out to the combustion chambers and their discharge nozzles is formed to provide substantially constant tensile stress parallel to the axis of the blade along the blade, the axis of the blade being constituted by the locus of the centroids of the cross-sectional areas of the blade, the plane of each cross-sectional area of the blade being normal to the blade axis, as illustrated, for example, by the cross-sections of FIGURES 6 to 13.

Such a constant stress is achieved when the blade portion is constructed and decreases smoothly and continuously in cross-sectional area such that each cross-sectional area taken normal to the blade axis is proportional to ewhere X is proportional to the radial distance outwardly from the axis of rotation of the rotor along the blade axis. I have found that such a blade can be conveniently formed by providing a slot formation 25, extending radially outwardly from the rotational axis of the rotor to adjacent to the combustion chamber and

discharge nozzle

23 and 24 at the end of the blade portion 1 of the rotor, the slot being formed in the face of the blade portion of the rotor, through which thev discharge nozzle 24 opens, and progressively widening and deepening along the blade axis outwardly from the rotational axis of the rotor.

By the provision of such a slot formation, the requisite cross-sectional area variation along the axis of the blade can be achieved while at the same time the blade can be formed to have a smooth and continuous variation in the shape of each cross-sectional area in proceeding from the axis of rotation to the combustion chamber.

It will be understood, of course, that the blade being vectorially opposite on opposite sides of the axis of rotation, the slot formations 25 on opposite sides of the axis of rotation will be formed in the opposite faces of the blade and face in the same direction as the respective nozzles 24 to which they are adjacent, such nozzles opening in opposite directions to direct products of combustion from the combustion chambers substantially tangentially of the rotational path of the blade, and in opposite directions to provide an additive reactive thrust to drive the blade in rotation.

.As seen particularly from FIGURE 18, the combustion chamber 23 and the discharge nozzle associated therewith formed at each tip of the blade is formed by an inner wall or loop 26 and an outer wall or loop 27. These walls or loops are formed to have the shape assumed by a flexible membrane hanging in a field of centrifugal 6 force somewhat similar to a catenary. These

walls

26 and 27 have their apices as designated at 26 and 27 lying in the plane of symmetry of the rotor, and their

bases

28 and 29 disposed symmetrically above and below the plane of symmetry, the bases being designated at the point where these catenary-like walls join the blade portion 1' of the rotor.

As will be seen from FIGURE 18, the wall 27 progressively increases in thickness from its apex 27' towards its base 29 over an appreciable extent. This wall is so constructed that the tensile stress in the loop will be substantially constant over such appreciable portion of its length so that the perimeter of such a loop for a given tip speed may be made a maximum to provide a maximum nozzle cross-sectional flow area for maximum mass flow therethrough for optimum output power of the device.

As shown in FIGURES 3, 4 and 6 and 14, the rotor is provided with air passages 30 for delivering air to the combustion chambers 23. These air passages are symmetrically duplicated on opposite sides of the plane of symmetry of the rotor, and enter the rotor on opposite sides of the plane of symmetry through a circular entrance 31 centered on the axis of rotation of the rotor, and opening through a reinforcing ring 32 integral with the rotor.

As shown in FIGURE 4, air entering each of the entrances 31 divides and flows laterally through the air passages 30 leading to the opposite ends of the rotor. Because of the symmetrical arrangement of the air passages, each combustion chamber is fed by a pair of air passages, one above and one below the plane of symmetry, these two air passages 30 finally emptying into the combustion chamber as at 33, as shown in FIGURE 15.

The fuel is delivered to the combustion chamber flowing outwardly from the axis of the rotor to the end of the blade portion 1 by means of fuel passages 34 as shown in FIGURE 4, and particularly FIGURE 21. These fuel passages, like the air passages, are duplicated on opposite sides of the plane of symmetry of the rotor, and at the axis of the rotor they lie immediately beneath the air passages 30 and extend parallel to each other. These passages 34 are fed by means of fuel passages 35 formed in the shaft 2 and the transfer of fuel from the shaft 2 to the passages 34 takes place through the provision of fuel outlets 36 formed on the underside of the contoured surfaces of the shoes 3 of the shaft 2, such shoes being hollow.

The contoured surface of the rotor lying beneath the shoes or feet 3 of the shafts have corresponding fuel inlets 37, as shown in FIGURE 5 particularly. In order to minimize stress concentration, the fuel inlets 37, and hence the fuel outlets 35, which are adapted to register or mate therewith, are formed as elongated ellipses ex-. tending longitudinally of the fuel passages 34 and hence of the axis of the blade, with the geometric centers of such elongated ellipses lying in plane normal to the axis of the blade and containing the axis of revolution of the rotor.

As will be seen from FIGURE 21, as the fuel passages are viewed progressively outwardly from the axis of rotation of the rotor, they commence to encircle the air passage 30 with which they are associated until, at the outer portion of the blade portion of the rotor, they completely encircle such air passage.

As will be seen from FIGURE 19, at the end of the blade portion of the rotor, the fuel passages 35 enter into distributing conduits 38 which extend substantially normal to the axis of the blade along the

bases

28 and 29 of the inner and

outer Walls

26 and 27 defining the combustion chamber and discharge nozzle at the respective end of the rotor. From the distributing conduits 38, the fuel is delivered to collecting conduits 39, which again extend substantially normal to the axis of the blade, and extend along the apices 26' and 27' of the

walls

26 and 6 27, respectively, emptying into the combustsion chamber 23.

The flow of fuel from the distributing conduits 38 to the collecting conduits 39 takes place through a network of extremely fine passages 40 connected in parallel and extending throughout the length of the combustion chamber and discharge nozzle as shown particularly in FIG- URE 19. It will be understood that the individual passages making up this network of fine passages 40 will each be contained in a plane substantially parallel to the axis of the blade of the rotor and substantially normal to the axis of a jet of products of combustion discharged from the nozzle.

Thus it will be seen from FIGURE 20 that the direction of fuel flow in the distributing conduits 38 is in the same general direction as the jet velocity vector 41, while the fuel flow in the collecting conduits 39 is in substantially the opposite directions.

In operation, the rotor 1 is adapted to rotate with tip speeds which may be of the order of 5,000 feet per second, and in operation, air entering through the collar formation 16 of the casing and rotor entrance 31 and flowing outwardly through the air passages 30 to the tips of the rotor, will be compressed substantially adiabatically in a pressure ratio of the order of 500 to 1, with the result that the temperature of such air will be raised to temperatures in the order of 2,000 degrees Fahrenheit.

The fuel, on the other hand, which is substantially noncompressible, will be delivered to the distribution conduits 38 under the action of centrifugal force at a static pressure in the order of 100,000 lbs. per square inch (p.s.i.). Since the collecting conduits 39 open to the combustion chamber, it will be understood that the fuel,

in passing from the distributing conduits 38 to the collecting conduits 39, will experience a pressure drop of the order of 90,000 p.s.i. which will enable the fuel to be delivered through the line network of passages 40. The fuel, on entering the combustion chamber 23 will have a velocity head equivalent to approximately 5,000 p.s.i. and will ignite spontaneously in the high temperature atmosphere of the combustion chamber, and will be discharged from the discharge nozzle 24. In this connection, it is to be pointed out that the velocity of the discharging jet of products of combustion has a Very high Mach number relative to the nozzle, and a moderately high Mach number relative to the casing.

The fact that the jet so discharged provides, by virtue of its supersonic velocity relative to the casing, a means of sustaining a partial vacuum in the casing, and at the same time provides for the efllux of the products of combustion from this partial vacuum to the outside atmosphere by virtue of the fact that the casing is constructed to define a configuration involving a construction or throat formation 9 permitting supersonic diffusion.

It will be understood that by virtue of the configuration of the fuel passages 34, as shown in FIGURE 21, the fuel will be utilized to cool the blade carrying olf heat resulting from the compression of the air within the air passage surrounded by the fuel passages adjacent to the outer end of the blade portion of the rotor.

Similarly, the extensive fine network of passages 40 will act to cool the walls of the discharge nozzle and combustion chamber to prevent excessive temperatures in such elements.

It will be understood that the distributing and collecting

conduits

38 and 39 will be large in cross-section as compared to the fuel passages 34, and the network passages 40 will be very fine in cross-section relative to both the fuel passages 34 and the

conduits

38 and 39.

Operation The device is operated as follows:

First, with the rotor stationary, the caps or covers 17 are moved inwardly by the hydraulic jacks 18 to close the entrance through the casing collar formations 16 and the valves 21 are opened to place the interior of the casing in communication with the high vacuum tanks 19 and the.

vacuum pumps 22 are actuated to draw ofi air from the interior of the casing and from the high vacuum tanks. It will be understood that the valves 12 will be in the closed position due to the action of the springs 13 and the excess of atmospheric pressure as evacuation of the casing takes place. i

The rotor 1 is then brought up to speed by means of a starter shown diagrammatically at 42 in FIGURE 2, which may comprise any suitable auxiliary power plant. When the rotor has been brought up to the required tip speed and the requisite partial vacuum has been established in the casing, the valves 21 connecting the interior of the casing to the high vacuum tanks are closed, fuel is introduced into the rotor by operating fuel pumps 43, shown diagrammatically in FIGURE 2, to cause fuel to enter the fuel passages 35 in the shafts 2 through suitable fittings 4 4, the fuel being subsequently delivered to the tips of the rotor under centrifugal force. The hydraulic jacks 18 are then actuated to lift the caps or covers 17 to allow entry of air through the casing collar formation 16, whereupon air will be delivered under centrifugal force at a high temperature to the combustion chambers 23, causing ignition of the fuel entering the combustion chambers as above described.

The products of combustion from the fuel chambers 23 are directed outwardly by the discharge nozzle 24 tangentially of the path of travel of the rotor, and in opposite directions at opposite ends of the rotor, to provide a jet reaction couple driving the rotor. As noted above, the jets leave the rotor at a very high Mach number relative to the rotor, and a moderately high Mach number relative to the casing. By virtue of the convergent form of the casing, which forms a throat or constriction 9 surrounding the rotor and centered on its plane of symmetry, the mechanism of supersonic diffusion is made possible whereby the products of combustion of which the jets are formed are removed from the interior of the casing, which is at a partial vacuum, to the outside atmosphere. In this connection, it will be understood that the valves 12 will remain closed until the supersonically diffusing products of combustion have attained a static pressure slightly in excess of atmospheric pressure thus forcing them open against the slight biasing of the springs 13, thereby allowing the products of combustion to escape to the atmosphere. 1

The mechanism of supersonic diifusion which permits the efilux of the products of combustion to be accomplished from a low pressure region within the casing to the relatively high pressure region of the atmosphere has the further important characteristic of sustaining the lower pressure atmosphere within the casing, despite the fact that the valves 12 are open, placing the interior of the casing in communication with the atmosphere through the throat formation 9, and the rotor can operate in a steady state operation without requiring the application of any vacuum to the interior of the casing. In the event, however, that some unbalance should occur, the valves 21 may be operated by a suitable pressure-sensitive switch (not shown) responsive to interior casing pressures, to place the casing in communiaction with the interior of the high vacuum tanks 19 to restore the system to the proper operating conditions, that is, steady state operation.

i It will be understood that any suitable hydrocarbon such as gasoline may be employed as the fuel, and the rotor will be of suitable high strength material of the nature, for instance, of tool steel.

It will also be understood that precise details in the arrangement and assembly maybe modified, as will be apparent to those skilled in the art without departing from the spirit of the invention or scope of the appended.

claims.

What I claim as my invention is:

1. A jet reaction prime mover comprising a rotor in the form of a blade element supported to rotate about a central axis within a casing and having a combustion chamber at each end thereof, said combustion chambers ally of the rotational path of said blade element to efiectf rotation thereof, said casing opening to the atmosphere through a discharge throat formation, and said blade element decreasing smoothly and continuously in cross-sectional area proportionate to ewhere X is proportional to the radial distance from the axis of rotation of the blade, said blade element having a pair of slots therein' disposed on opposite sides of said rotation axis and'on opposite sides of said blade, each slot formation extending substantially from the axis of rotation to adjacent to the combustion chamber discharge nozzle on its respectiveside of the blade, each of said slots being progressively wider and deeper along its length outwardly from said rotation axis, and terminating at its outward end in a Wall defining one Wall of said adjacent combustion chamber discharge nozzle,

2. A device as claimed in claim 1 in which each of said combustion chamber discharge nozzles formed at the ends of said blade is defined by an inner wall comprising said end wall of the adjacent slot and a spaced outer' wall said inner and outer walls having a loop configuration corresponding to the configuration that would be assumed by a flexible membrane hanging in a centrifugal force field, the loop configuration of the outer of said walls having an apex at the outermost end of the rotor and progressively increasing in thickness over a substantial portion of the length thereof on opposite sides of, said apex to provide for substantially uniform tensile stress along a substantial portion of the length of said outer wall.

3. A jet reaction prime mover comprising a rotor in the form of a blade element supported to rotate about a central axis within a casing and having a combustion chamber and a discharge nozzle at each end thereof, and having air and fuel passage means leading to said combustion chambers, said blade element having a plane of symmetry normal to its axis of rotation, and being identical and opposite on opposite sides of the axis of rotation, said blade element decreasing smoothly and continuously in cross-sectional area along its length outwardly from said rotation axis and the combustion chamber and discharge nozzle at each end thereof is defined by a pair of spaced inner and outer loops having their apices contained in and being symmetrical on opposite sides of said plane of symmetry, said discharge nozzles defined by said loops opening laterally at opposite ends of said blade through opposite faces of said blade to direct products of combustion from said combustion chamhers as jets directed substantially parallel to the plane of symmetry and tangential to the path of rotation of said blade to rotate said blade, said blade having a slot extending substantially from said rotational axis to adjacent to the discharge nozzle at each end of said blade, said slot being formed in the face of the blade through which its respective discharge nozzle opens, and being bisected by said plane of symmetry and progressively widening and deepening radially outwardly from said rotation axis, said casing opening to the atmosphere through a discharge throat formation bisected by said plane of symmetry, said discharge nozzle being defined by an inner wall which defines the outer end of the adjacent slot and an outer wall spaced radially outwardly from said inner wall.

4. A device as claimed in claim 3 in which said air passage means comprise a pair of air passages symmetrically disposed with respect to said plane of symmetry,v

leading from the rotation axis of said blade to each combustion chamber.

5. A device as claimed in claim 4 in which said fuel passage means comprise a system of passages associated with each air passage and leading from the axis of rotation of the blade to each combustion chamber, said fuel passages being parallel and coplanar in the vicinity of the axis of rotation and completely surrounding their respective air passage in the vicinity of the combustion chamber.

6. A device as claimed in claim 5 in which said fuel passages have entrances thereto at said rotational axis, said entrances comprising elongated elliptical openings extending longitudinally of said fuel passages with the geometric center of each elliptical opening midway between the ends of said blade.

7. A device as claimed in claim 5 in which said fuel passages terminate in distribution conduits extending in the direction of said jets along the bases of said inner and outer loops defining each combustion chamber and discharge nozzle, said inner and outer loops having collecting conduits formed in the apices thereof substantially parallel to said distribution conduits and opening into the respective combustion chamber, said distribution and collecting conduits being large in cross-section compared with said fuel passages and being in communication throughout their length through a system of substantially parallel cooling passages connected in parallel and having a cross section small in relation to both the cross section of said conduits and the fuel passages leading to said distribution conduits.

8. A rotor for a jet reaction prime mover having a hub formation having an axis about which said rotor is adapted to rotate, said rotor having a plane of symmetry normal to said axis and being identical and opposite on opposite sides of said axis, said rotor having at each end thereof a combustion chamber and discharge nozzle and having air and fuel passages leading to each of said combustion chambers from said hub formation, said rotor decreasing smoothly and continuously in cross sectional area along its length outwardly from said axis and the combustion chamber and discharge nozzle at each end thereof being defined by a pair of spaced inner and outer loops having their apices contained in and being symmetrical on opposite sides of said plane of symmetry, said discharge nozzles defined by said loops opening laterally at opposite ends of said rotor through opposite faces of said rotor to direct products of combustion from said combustion chambers as jets directed substantially parallel to the plane of symmetry and normal to the length of the rotor, said rotor having a slot extending substantially from said axis to adjacent to the discharge nozzle at each end of said rotor, each of said slots being formed in the face of said rotor through which its respective discharge nozzle opens, and being bisected by said plane of symmetry and progressively widening and deepening radially outwardly from said rotation axis, said hub formation comprising at its most remote points from the plane of symmetry and on opposite sides thereof an annular reinforcing ring centered on said axis.

9. A device as claimed in claim 8 in which said air passages comprise passages having their entrances defined by said annular rings and leading radially from said annular rings to said combustion chambers, said air passages being symmetrical on opposite sides of said plane of symmetry.

10. A device as claimed in claim 9 in which said fuel passages comprise a system of passages associated with each air passage and at said hub lying inwardly of the respective air passage in relation to said plane of symmetry and being substantially parallel to each other and to the plane of symmetry, said fuel passages opening to the interior of each of said rings through elliptical openings extending longitudinally of said fuel passages and having their geometric centers midway between the ends of said rotor, and means for directing fuel through said openings into said fuel passages.

11. A device as claimed in claim 10 in which said fuel directing means comprises a pair of hollow shafts terminating in hollow foot formations having a series of elliptical openings in the bottom thereof corresponding to and adapted to overlie and registeringly engage with the aforesaid elliptical openings, said shafts and foot formations being received within said rings and engaging said rotor in compression therebetween.

12. A device as claimed in claim 11 in which said foot formations and the rotor surface having said elliptical openings therein engaged by said foot formations have mating contours.

13. A jet reaction prime mover comprising a rotor having a central axis, a casing means mounting said rotor in said casing to rotate about said central axis, said rotor having combustion chambers at the ends thereof, said combustion chambers having discharge nozzles opening to the exterior of said rotor in opposite directions at opposite ends of said rotor to direct products of combustion from said combustion chambers outwardly from said rotor tangentially of the path of rotation of said rotor, said casing opening to the atmosphere through a throat formation encircling said rotor, means for applying a partial vacuum to said casing preparatory to starting said rotor, and means for closing said casing to the atmosphere during operation of said partial vacuum applying means preparatory to starting said rotor, said rotor having an annular hub formation forming an entrance permitting air intake, a shaft to be driven concentrically disposed within said hub, said hub being connected to said casing through a labyrinth seal, and cover means slidable along said shaft for opening and closing the air intake entrance formed by said hub.

14. A device as claimed in claim 13 in which said means for closing said casing to the atmosphere comprise pressure responsive valve means associated with said throat formation.

15. A device as claimed in claim 13 in which said means for applying a partial vacuum to said casing comprise a high vacuum tank, passage means leading from said high vacuum tank to said casing, and valve means controlling fluid flow in said latter passage means.

References Cited in the file of this patent UNITED STATES PATENTS 2,637,166 Carswell May 5, 1953 FOREIGN PATENTS 801,281 Great Britain Sept. 10. 1958