US2182719A

US2182719A - Rotary fluid pressure engine and the like

Info

Publication number: US2182719A
Application number: US160953A
Authority: US
Inventors: Booth Ernest
Original assignee: Keelavite Co Ltd
Current assignee: Keelavite Co Ltd
Priority date: 1936-09-08
Filing date: 1937-08-26
Publication date: 1939-12-05
Anticipated expiration: 1956-12-05

Description

Dec. 5, 1939. BOOTH 2,182,719

ROTARY FLUID PRESSURE ENGINE AND THE LIKE Fi led Aug. 26, 193 7 2 S heets-She et 1 g0 17 21 28 12 n /'V \I A A l 22 24 23 V I8 3 a V4 1 2 -27. 22 T 2 AT 25 5 k a 6 v "7 'l 22 24 8 x Q -11 28 Fig. 2. 28 3 4- fk/l INVENTOI? Y rncst' 500th Dec. 5, 1939. v BOOTH 2,182,719

ROTARY FLUID PRESSURE ENGINE AND THE LIKE Filed Aug. 26, 193'? '2 Sheets-Sheet 2 4 ATTORNEY 8 ErneSUBw'th Patented Dec. 5,1939

' UNITED STATES PATENT OFFICE ROTARY FLUID PRESSURE ENGINE AND THE LIKE Great Britain Application August 26,

1937, Serial Nn- 16 ,95

In Great Britain September s, i335 13 Claims.

This invention relates to rotary fluid pressure engines, pumps, motors, meters and the like adapted to be operated by or to operate upon a fluid, hereinafter termed the working fluid, and

: whether employed primarily to .act on or to be operated by the working fluid or employed as or incorporated in devices, such as transmission devices.

For brevity, such engines, pumps, motors, meters and the like ,will be referred to herein as rotary engines.

This invention concerns rotary engines of the kindcomprising members which enclose between theman annular bladechamber and are rotatable relatively .to one another about the axis of the blade chamber, at least oneabutment fixed to one of the-members and extending across the chamber between inlet and outlet ports and. blades whichare peripherally part-circular in cross-sec- .tionand rotate continuously about their own axes in recesses in one of the radially opposed peripheries of the chamber, this periphery being carried upon the other member, and are so shaped that .during relative rotation of the members each blade projects across the blade chamber and makes a sealing fit with the opposite periphery as the blade passes through the part orparts of the chambernot occupied by an abutment but recedes into and is wholly contained in its recess during its passagepast the abutmentor abutments. It will be understood that since each blade must be wholly contained in its recess as it passes an abutment there will be a transitional period immediately before and after each blade passes an abutment during which it is respectively receding into its recess and emerging from it and does not therefore make a sealing fit with the opposite periphery of the blade chamber although it is passing through parts of the blade chamber not occupied by an abutment.

Theper'iphery in which the blade recesses are formed will be hereinafter termed the bladehousing periphery and the opposite periphery will be termed the blade-sealing periphery. Further, each part of a blade which lies between peripherally circular sealing parts and constitutes agap in the peripherally circular surface of the blade to permit passage past an abutment will be referred to as a non-sealing part of the blade. It will also be assumed in describing the invention that the member carrying the abutment or abutments j is stationary and that carrying the blade-housing periphery rotatesbut it is to be understood that the invention is applicable to other arrangements in which relative rotation takes place between the two members.

With rotary engines of the general kind re- --ferred toabove, employing as hitherto blades of approximately segmental cross-section, it is im- A itces to ha the-' pn-. a ine t r rt of the blades so as to conform with the surface of the abutment's adjacent to which they pass In consequence, in the case of a pump or'compressor apart of the'working fluid is transferred by the space thus left from the delivery or high pressure side of the abutment to the inlet orlow pres sure side. A similar effect may also take place due to the fact that during the passage of the blade through the part of the blade chamber not occupied by the abutment (hereinafter referred to as the swept part of the blade chamber) the blade does not completely fill the recess'in which it rotates but a space is left therein by the nonsealing part or parts of the blade, this space communicating first with the inlet side of the 'blade chamber and then, after'being closed to both sides thereof, with the outlet side. This, in' the case of an engine or motor, results in a certain degree of transference of working fluid from the high to the low pressure side of the blade, andin the case of a pump a sudden rush of working fluid 'into the space as it comes into communication with the high pressure side of the blade chamher, which may produce a certain degree of back pressure effect.

The object of the present invention is to provide certain improvements in rotary engines of the-kind referred to which will reduce or eliminate the above difliculties.

To this end according to the present invention the-blades ofa-rotary engine of the kind referred .to are of-part annular cross-section and the recesses in the bladehousing peripheryare similarly ofpart-annular.cross-section, that is .to say -in-the form ofv part-annular slots which accom- -m0date ,the blades as they pass the abutment or abutments but from which they emerge during theirrotation about their own ax es relatively tothe b lade-housing periphery to make an approximately fiuid-tight seal with the blade-seal-v mg periphery.

In this way the .width of the dead space between each blade and thesurface of an abutment adjacent towhich it passes, is confined to the width of, the. ends ,ofthepart-annular slot in which the chamber is less than with' the previous form of blade so that difiiculties due to the fact that this unoccupied portion of the recess isbrought successively intov communication with the inlet and outlet portions of the bladechamber are cor-' respondingly reduced.

Preferably the blade sealing periphery is formed or carried .on thesame member as the .bl wheniea i e O h the W 2 blade rotates instead of extending over the whole through the swept part or parts of the blade".

ripheries rotate together. In this case, the

blade-sealing periphery is provided opposite each blade recess with a groove having a part-circular surface of the same centre and radius of curva-' ture as the outer surface of the blade recess so as to make a seal with the part-circular surface of the blade when the blade extends across the blade chamber. It will be seen that with this arrangement each blade recess and the groove may be made in a single turning operation, the groove in fact forming in effect a part of the outer surface of the blade recess where this outer surface, after being interrupted by the blade chamber, cuts into the blade-sealing periphery. This arrangement not only provides area sealing between the blades and the bladesealing periphery but also has the advantage that it renders unnecessary complete accuracy in the positioning of the axes of the blades since slight inaccuracies will merely result in a slightly wider or narrower groove without affecting the obtaining of a substantially pressure-tight fit between the blades and the bladesealing periphery.

In rotary engines of the kind referred to the blades conveniently rotate relatively to the bladehousing periphery in a direction opposite to that in which this periphery rotates. With the present invention when the leading edge of a partannular blade has passed the leading edge of an abutment, a portion of working fluid becomes trapped in the open end of the annular slot in which the blade moves and the continued movement of the blade tends to compress this trapped fluid. Further, in an oil-lubricated gaseous fluid engine, lubricating oil may be similarly trapped. In order to meet this difficulty according to a further feature of the invention, as is more particularly desirable when the working fluid is substantially incompressible, provision may be made for placing the leading end of each blade recess, as it passes an abutment, first into communication with the outlet side of the blade chamber and then, when the trailing end of the blade recess has passed the leading edge of the abutment, into communication with the trailing end of the blade recess. In this way, the building up of excessive pressure in the recess by the advancing end of the blade is prevented and substantial equalisation of the pressure acting respectively on the leading and trailing edges of the blade is ensured. For example, the radius of curvature of the periphery of the concentric member in which the blade recesses are formed may be made slightly less between the two ends of each blade recess than over the remaining portions of the said periphery which effects a seal with the abutment. Alternatively, the same result may be obtained by the use of suitable slots or ports.

An important incidental advantage of the invention is that since the concentric member in which the blades rotate has portions which extend axially into the part-annular blades and form the inner walls of the annular blade recesses, the bearings for supporting these blades may lie in these portions and can therefore be of needle or elongated roller type without unduly increasing the overall axial length of the engine.

The invention may be carried into practice in various ways but one construction according to the invention is shown somewhat diagrammatically by way of example in the accompanying drawings which also show a modification of the invention and include diagrammatic views to illustrate the general principle of the invention.

In the accompanying drawings Figure 1 is a longitudinal axial section through one construction of rotary engine according to the invention,

Figure 2 is a cross-section through the engine shown in Figure 1 taken on the line ]III of Figure Figures 3, 4 and are diagrammatic views for the purpose of illustrating more clearly the general principle of the invention, and

Figure 6 illustrates a constructional modification of the invention.

In the construction illustrated in Figures 1 and 2 the engine, which is of the same general con struction as that described with reference to Figures and 11 in the specification of United States of America patent application Serial No. 88,231, comprises a generally cylindrical rotor I and a stator 2. The stator 2 comprises

end walls

3 and 4 through one of which passes a power shaft 5 rigidly connected to the rotor and supported in a ball bearing 6 while the other carries a ball bearing 1 for supporting the other end of the rotor, as shown.

Formed in the rotor I and concentric therewith are two annular recesses 8 and 9 extending into the rotor from opposite ends thereof and constituting annular blade chambers. the stator casing 2 into each annular chamber between an inlet Ill and an outlet II for working fluid is an abutment, these abutments being designated by the reference numerals I2 and I3. The inner part of the rotor I, that is to say the part forming the inner walls of the recesses 8 and 9, is provided with a pair of recesses I4 and I5 of part-annular cross-section the axes of which are parallel to one another and to the axis of rotation of the rotor I and are formed as shown. The axial length of the recesses I4 and I5 is substantially equal to the distance between the outer end wall of the blade chamber 8 and the outer end wall of the opposite blade chamber 9 and moving within each recess is a blade I6 of part-annular section the axial length of which is substantially equal to the said axial length of the recesses I4 and I5. It will thus be seen that the inner part of the rotor I forms the blade-housing periphery. Each blade I 5 is formed with a central web I! which serves to connect the part-annular peripheral portion of the blade to a blade shaft I8 the end portions of which lie in tunnels 22 in the central portion of the rotor. The peripheral surface of each web I1. is circular where it extends through the gap in the circumference of the blade and has a radius of curvature equal to that of the outer periphcry of the blade. Further, the part of each web which extends through the gap in the blade may be solid while the part lying between the shaft I8 and the blade may be hollow, so as to provide for dynamic balance of the blade as it rotates around the axis of its shaft.

As will be understood, the rotor I is provided with short cylindrical recesses I9 to receive the webs II, the axial length of these recesses being substantially equal to the axial length of the webs.

Each blade shaft I8 is provided with a pair of needle type roller bearings 20, 2I disposed in the cylindrical tunnels 22 in the central portion of the rotor I and also with a ball bearing 23 constituting an additional support.

The blade shafts and with them the blades Extending from are arranged to rotate in the rotor about their own axes in a direction opposite to that in which the rotor rotates and in such a manner that each.

secured to the blade shafts la, a fixed sun wheel 25 mounted on the stator casing Z and a pair of

intermediate gear wheels

26, 21 each meshing with ,one of the planet wheels Ziand with the sun wheel 25. Other forms of gearingor other j mechanisms may, however, be employed instead of that described for causing the desired rotation of the blades in their recesses about their own axes as therotor revolves.

Formed in the outer periphery of each blade chamber opposite each blade recess, that is to say in the blade-sealing periphery, is an axially extending channel 28 the surface of which is concentric with the blade recesses l4, l5 and forms in effect a continuation or part of the outer surface of the blade recess so that the outer periphery of the blade, as it passes during rotation over thesurface of the channel will make therewith a fine-clearance sealing fit. Thus, in turning the blade recesses, the channels are automatically formed and it will beseen that in this way satisfactory sealing between the blades and the blade-sealing periphery can be obtained without the necessity for ensuring complete accuracy in the positions of the blade axes and moreover that area sealing is obtained between the blade and the outer as well as. the inner periphery' of the blade chamber with the consequent advantages of such form of sealing over line sealing.

' It will be appreciated that the other relatively moving surfaces of the engine which in operation effect a sealing fit conveniently effect a fine-clearance sealing fit. Thus, the inner. peripheries of the blade chambers 8'and 9 conveniently effect 'a fine-clearance sealing fit with the inner faces of the abutments l2 and I3 and similarly the outer peripheries of the blade chambers effect a fine-clearance sealing fit with the outer surfaces of the abutments. ends 'of the abutments conveniently effect a fine-clearance sealing fit not only .with the web IT but with the central web portion of the rotor which extends radially in the plane of the web l'i between the adjacent ends of the blade chambers 8 and 9.

Similarly, the outer circumferential surface of the rotor effects a fine-clearance sealing fit with the surrounding portion of the stator casing 2.

Referring to Figures 3, 4 and 5, which are cross-sections of engines of the kind referred to through the rotor, the abutment and one blade, Figure 3 shows an arrangement in which, as hitherto, the blades are of approximately segmental form as applied to a construction in which the stator casing forms the outer peripheryof the blade chamber and the blades thus make a fine-clearance line sealing fit with this outer periphery as they rotate in their recesses and bodily with the rotor.

In this construction the'rotor is designated i the stator 2 the inlet and outlet ports w and H respectively, the annular blade chamberB the abutment l2 and the blades |6*--. It willbe seen that in the construction illustrated inFigure 3, which shows the rotor in the position. in which a blade is passing the abut-- For this purpose epicyclic' Again, the opposed ment 12 there is a considerable volume of dead space in the blade recess between the non-sealing part of the blade and the surface of the abutment.

F-igures4 and 5 show respectively two positions of the rotor in a construction according to the invention as illustrated in Figures land 2.

Thus Figure 4 shows the rotor at a corresponding position to that shown in Figure 3 and it willbe seen that with the construction according to the invention the dead space left in the blade recess is very considerably less, being limited to the two end portions of the annular recess 14.

Figure 5 shows the rotor in the position in which the leading end of the blade recess has passed the leading edge of the abutment 12 while the trailing end of the blade recess is still in the blade chamber. continued rotation of therotor into the position shown in Figure 3', the movement of the blade will tend to compress fluid between its leading edge and the abutment [2. In order to overcome this difficulty, one or more shallow grooves 30 may be formed between the ends of each blade recess orthe radius of curvature of the surface of the recess may be slightly reduced to provide an escape channel. This channel forms a passage through which working fluid can escape from the space in the blade recess in front of the advancing edgeof the blade. It will be seen that the channel 30 will communicate with the outlet side of the blade chamber until cut off by the portion of the periphery of the rotor immediately behind the trailing end of the blade recess, after which and until'the'leading end of the recess passes from the trailing edge of the abutment, the channel 30 can serve as a transfer passage along which fluid can pass from one end of the blade recess to the other.

In order to increase the efficiency of a rotary engine according to the invention, more particularly where the operating fluid is compressible, as in the case of an air compressor, a non-return check valve may, if desired, be fitted in the outlet from the blade chamber, this check valve being preferably arranged as near to the outlet end of the blade chamber as possible. In this way back pressure which would otherwise operate on the blades throughout the major portion of their effective travel around the blade chamberwill be cut off by the non-return valve which will, how ever, open automatically as the fluid in front of each blade reaches the requisite pressure to permit such fluidto pass to the outlet.

Figure 6 illustrates such a modification of the invention as applied to a construction which may be generally similar to that illustrated in Figures 1 and 2. Thus, in Figure 6, a non-return valve, indicated at 31, is arranged in the outlet passage 11.

Figure 6 also illustrates a modification designed to provide a higher compression ratio when operating with or upon air or like compressible working fluid and when employing a non-return valve such as that referred to above. In this construction the side of the abutment adjacent to the outlet H is extended, as shown at 32, and given an inner contour over this extended part which conforms approximately to the path traversed by'the rear edge of each blade after it has broken the seal with the outer periphery of the blade chamber preparatory to passing the abutment. In this way, it will be seen that the volume of fluid between each blade and the abutment immediately before the blade breaks seal withthe outer periphery of the'blad e'chamber It will be seen that during v is reduced and the compression ratio thus increased.

It is to be understood that the present invention may be applied to rotary engines of the kind described in the specifications of United States of America patent applications Serial Nos. 88,231 and 88,232, in which means are provided for varying the effective length of the blade chamber and thereby the capacity of the engine.

It is also to be understood that the construc tional forms of the invention may vary considerably. For example, in a construction generally similar to that shown in Figures 1 and 2, the channels 28 may be omitted and the peripheries of the blades may make a line sealing fit with the outer periphery of the blade chamber. Where high volumetric efficiencies are desired, however, it is usually preferable to provide the channels which thus give area sealing as between the blades and the outer periphery of the blade chamber.

Where the invention is applied to a power transmission device, it will be appreciated that the said device, if for use as a slipping clutch, may comprise a single rotary engine according to the invention with means for restricting or closing the outlet at will, while, if for use as a torque converter, may comprise two rotary engines according to the invention coupled together so that the fluid delivered by one constituting a pump is supplied to the other, operating as a motor, with or without means for varying the capacity of one or each of the rotary engines for the purpose of varying the torque or speed ratio transmitted by the device. Further, it will be appreciated that the rotor, stator and other parts may be built up in various ways as may be found convenient.

What I claim as my invention and desire to secure by Letters Patent is:

l. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of this blade chamber, at least one abutment rigid with one of the members and extending across the blade chamber be tween inlet and outlet ports which are stationary with respect to the abutment, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess in one of the radially opposed peripheries of the blade chamber with its axis of rotation lying within said one periphery, said one periphery being carried by the member not carrying the abutment, each blade being of such dimensions as at all times to lie at least partly within its part-annular recess but being capable of projecting across the blade chamber to make an approximately fluidtight seal with the opposite periphery or of lying wholly within its recess according to its rotational position, and means for causing continuous rotation of the blades in their recesses during relative rotation of the two members and in such timed relation to the relative rotation of these two members that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment.

2. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of that blade chamber, the two radially opposed peripheries of the blade chamber being constituted by parts of one of the two members, at least one abutment rigid with the other of the two members and extending across the blade chamber between inlet and outlet ports which are stationary with respect to the abutment, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess vin one of the radially opposed peripheries of the blade chamber with its axis of rotation lying within that periphery, this periphery being carried by the member not carrying the abutment, each blade being of such dimensions as at all times to lie at least partly within its part-annular recess but being capable of projecting therefrom across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly in its recess according to its rotational position and means for causing continuous rotation of the blades in their recesses during relative rotation of the two members and in such timed relation to the relative rotation of these two members that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess a during its passage past the abutment.

3. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of that blade chamber, the

two radially opposed peripheries of the blade chamber being constituted by parts of one of the two members, at least one abutment rigid with the other of the two members and extending across the blade chamber between inlet and outlet ports which are stationary with respect to the abutment, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess in one of the radially opposed peripheries of the blade chamber with its axis of rotation lying within that periphery, this periphery being carried by the member not carrying the abutment, each blade being of such dimensions as at all times to lie at least partly within its part-annular recess but being capable of projecting across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly in its recess according to its rotational position, the periphery of the blade chamber opposite each blade recess being provided with a groove whose surface is concentric with and has the same radius of curvature as the outer surface of the blade recess so as to provide area sealing between the outer surface of the blade and this groove, and means for &

causing continuous rotation of the blades in their recesses during relative rotation of the two members and in such timed relation to the relative rotation of these two members that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment.

4. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of this blade chamber, at least one abutment rigid with one of the members and extending across the blade chamber between inlet and outlet ports, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess in one of the radially opposed peripheries of the blade chamher, this periphery being carried, by the member not carrying the abutment, each blade being capable of projecting across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly within its recess according to its rotational position, means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, and means for placing the leading end of each blade recess, during its passage past an abutment, first in communication with the outlet side of the blade chamber and then, while both ends of the recess lie opposite the abutment, in communication with the trailing end of the recess.

5. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of that blade chamber, the

two radially opposed peripheries of the blade chamber being constituted by parts of one of the two members, an abutment rigid with the other of the two members and extending across the blade chamber between inlet and outlet ports, blades of part-annular cross-section rotatably mounted in part-annular recesses in one of the radially opposed peripheries and each capable of projecting therefrom across the blade chamber to make a substantially fluid-tight seal with the other periphery or of lying wholly in its recess according to its rotational position, means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, and means for placing the leading end of each blade recess, during its passage pastan abutment,first in communication with the outlet side of the blade chamber andthen, while both ends of the recess lie opposite the abutment, in communication with the trailing end of the recess.

6. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of that blade chamber, the two radially opposed peripheries of .the blade chamber being constituted by parts of one of the two members, an abutment rigid with the other of the two membersand extending across the blade chamber between inlet and outlet ports, blades of part-annular cross-section rotatably mounted in part-annular recesses in one of the radially opposed peripheries and each capable of projecting therefrom across the blade chamber to make a substantially fluid-tight seal with the other periphery or of lying wholly in its recess according to its rotational position, the periphery of the blade chamber opposite each blade recess being provided with a groove whose surface is concentric with and has the same radius of ourvature as the outer surface of the blade recessso as to provide area sealingv between the blade and this groove, means for causing continuous rotation of the blades in their'recesses during relative rotation of the two 'members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment,'and means for placing the leading end of each blade recess, during its passage past an abutment, first in communication with the outlet side of the blade chamber and then, while both ends of the recess lieopposite the abutment, in communication with the trail- I the member not carrying the abutment, each blade being capable of projecting across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly within its recess according to its rotational position, and means for causing continuous rotation of the blades in their recesses during relative rotation of the two members sothat each blade projects across the blade chamber as it passes through the part of the blade chamber not c,- cupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, those parts of the periphery containing the blade recesses which lie between the ends of each blade recess being slightly reduced in diameter as compared with the remaining parts of this periphery.

8. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of that blade chamber, the two radially opposed peripheries of the blade chamber being constituted by parts of one of the two members, an abutment rigid with the other of the two members and extending across the blade chamber between inlet and outlet ports, blades of part-annular cross-section rotatably mounted in part-annular recesses in one of the radially opposed peripheries and each capable of projecting therefrom across the blade chamber to make a substantially fluid-tight seal with the other periphery or of lying wholly in its recess according to its rotational position, and means for-causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, those parts of the periphery containing the blade recesses which lie between the ends of each blade recess being slightly reduced in diameter as compared with the remaining parts of this periphery.

9. A rotary engine comprising two members which enclose between them an annular blade chamber and 'are' rotatable relatively to one an'-' other about the axis of that blade chamber, the 7 projecting therefrom across the blade chamber tog'make a substantially fluid-tight seal with the other periphery or of lying wholly in its recess according to its rotational position, the periphery of the blade chamber opposite each blade recess being provided with a groove whose surface is concentric with and has the same radius of ourvature as the outer surface of the blade recess so as to provide area sealing between the blade and this groove, and means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, those parts of the periphery containing the blade recesses which lie between the ends of each blade recess being slightly reduced in diameter as compared with the remaining parts of this periphery.

10. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of this blade chamber, at least one abutment rigid with one of the members and extending across the blade chamber between inlet and outlet ports, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess in one of the radially opposed peripheries of the blade chamber so that portions of the member in which the part-annular recesses are formed extend axially into the blades, said one periphery being carried by the member not carrying the abutment, each blade being capable of projecting across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly within its recess according to its rotational position, blade supporting bearings disposed at least partly within those portions of the member containing the blade recesses which extend axially into the blades, and means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment.

11. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of this blade chamber, at least one abutment rigid with one of the members and extending across the blade chamber between inlet and outlet ports, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess in one of the radially opposed peripheries of the blade chamber, this periphery being carried by the member not carrying the abutment, each blade being capable of projecting across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly within its recess according to its rotational position, means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, and a non-return valve closing the fluid outlet and disposed inclose proximity thereto, the side of the abutment adjacent to the outlet having a contour which conforms closely to the path traversed by the trailing edge of each blade as itpasses across the blade chamber into its recess preparatory to passing the abutment.

12. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of that blade chamber, the two radially opposed peripheries of the blade chamber being constituted by parts of one of the two members, an abutment rigid with the other of the two members and extending across the blade chamber between inlet and outlet ports, blades of part-annular cross-section rotatably mounted in part-annular recesses in one of the radially opposed peripheries and each capable of projecting therefrom across the blade chamber to make a substantially fluid-tight seal with the other periphery or of lying wholly in its recess according to its rotational position, the periphery of the blade chamber opposite each blade recess being provided with a groove whose surface is concentric with and has the same radius of ourvature as the outer surface of the blade recess so as to provide area sealing between the blade and this groove, means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment, and a non-return valve closing the fluid outlet and disposed in close proximity thereto, the side of the abutment adjacent to the outlet having a contour which conforms closely to the path traversed by the trailing edge of each blade as it passes across the blade chamber into its recesses preparatory to passing the abutment.

13. A rotary engine comprising two members which enclose between them an annular blade chamber and are rotatable relatively to one another about the axis of this blade chamber, at least one abutment rigid with one of the members and extending across the blade chamber between inlet and outlet ports, blades each of which is of part-annular cross-section and is rotatably disposed in a part-annular recess in one of the radially opposed peripheries of the blade chamber so that portions of the member in which the part-annular recesses are formed extend axially into the blades, said one periphery being carried by the member not carrying the abutment, each blade being capable of projecting across the blade chamber to make an approximately fluid-tight seal with the opposite periphery or of lying wholly Within its recess according to its rotational position, blade-supporting bearings of the elongated roller type disposed at least partly within those portions of the member containing the blade recesses which extend axially into the blades, and means for causing continuous rotation of the blades in their recesses during relative rotation of the two members so that each blade projects across the blade chamber as it passes through the part of the blade chamber not occupied by an abutment but recedes into and is wholly contained in its recess during its passage past the abutment.

ERNEST BOOTH.