US2207749A - Birotary engine - Google Patents

Description

July 16, 1940. A. J. MEYER BIROTARY ENGINE FiledOct. 18, 19:58

ATTORNEY 2 Sheets-Sheet 1 July 16, A. J. MEYER BI'ROTARY ENGINE 1 Filed Oct. 18, 1938 2 Shets-Shet 2 Patented July 16, 1940 UNITED STATES PATENT OFFICE BIBOTARY ENGINE Application October 18, 1938, Serial No. 235,571

25 Claims. (Cl. 121-59) The present invention relates to engines and has particular reference to engines of the type in which a bank of radially arranged cylinders is mounted for relative rotary movement with re- 5 spect to an annular ported valve member encircling the cylinder bank and controlling the flow of gases to and from the cylinders. Engines of this kind may be constructed with the valve member stationary and the cylinder bank rotating or with the valve member and cylinder bank both rotating, but at different speeds, so as to produce relative rotary movement therebetween. In the former case, which is usually the preferred construction, the cylinder bank and crankshaft are both mounted for rotary movement, the relative movement between these parts being governed by gearing connecting the two. In such cases the cylinder bank and crankshaft may rotate in the same or opposite directions. In the 20 case where both cylinder bank and valve member rotate, the crankshaft is ordinarily stationary but this part also may rotate. In all cases, however, at least two ofthe major components on-the engine, one of which includes the valve --mmbgr and the other the fiy bank have a relative rotary movement and engines of this kind may therefore conveniently be referred to as birotary-engines regardless of the components of the engine which are chosen to have absolute rotation or the relative direction of rotation with respect to each other of the components which have relative rotary movement.

Birotary engines are particularly suited for air craft propulsion, which requires lower speed of rotation for the propeller drive than the most efficient \speed of rotation of the component of the engine from which power usually is taken. Consequently, in engines of this kind, reduction gearing is often required between the power shaft and the component of the engine from which it derives power-and this reduction gearing may conveniently be-combined with the gearing which connects the crankshaft and cylinder bank to maintain themin properly timed relation.

In engines of all kinds, one of the characteristics of operation is vibration due to variations in the value of the torque reaction of the engine.

In automotive types of engines the eifect'of such vibration has been greatly reduced and in fact 50 substantially eliminated by the use of highly resilient mountings between the engine and the structure in which it is mounted, such mountings being commonly referred .to as floating power engine mountings. These mountings are not only resilient but in many instances are so placed with reference to the center of gravity of the engine that the inertia of the mass of the engine itself assists in neutralizing the vibration due to variation in torque reaction. In radial engines, comparatively little has been done to neutralize vibration, due to torque reaction variations, the reason for this being that the problem is exceedingly difiicult to solve for this type of engine, due among other things to the fact that in the usual aircraft installation of radial engines no front support is practically obtainable for the stationary part of the engine.

In the birotary engine, particularly in that type of birotary engine in which the cylinder bank and crankshaft rotate in opposite direc- 1g tions, an unusual condition exists from which it has been inferred that the engine is inherently balanced with respect to torque reaction. This, however, can be shown by analysis to be not the case, and a primary object of the present invention is to provide a new and improved construction in birotary engines whereby in a very simple and practical manner vibration due to variations in torque reaction of the engine can be substantially neutralized. A further general object of the invention is to provide a novel and practical arrangement of gearing which will accomplish the desired function of providing properly timed relative-rotation between the relatively rotating components of the engine; which is well adapted to be used in combination with means for neutralizing variations in torque reaction and which is also well adapted in addition to its other functions to providefor a gear reduction between the power output shaft of the engine and the power delivering component of the engine from which the power is primarily derived.

Other and more detailedobiects of the invention, the manner in which the several objects are achieved, and the advantages to be derived 0 fromthe useof the invention will best be understood from a consideration of the ensuing portionof this specification, in which is described by way of example a preferred embodiment of construction, taken in conjunction with the accompanying drawings in which:

Fig. 1 is a side elevation of a birotary engine embodying the invention;

Fig. 2 is a front elevation of the engine shown in Fig. 1;

Fig. 3 is a side view, partly in elevation and partly in section and on enlarged scale, of a part of the engine'shown inl 'lg. 1;

' Rig. 4 is a section taken on line 4-4 of Fig. 3; and 55 Fig. 5 is a diagram illustrating the nature of the motions derived from the gearing illustrated in Fig. 3.

Referring now to the drawings, the engine illusture comprises front and rear casing members l8 and 12, respectively, between which the annular ported valve member I4 is fixed. In the embodiment illustrated, the engine is secured to the structure carrying it by means of suitable mounting brackets i8 formed on the rear casing member I2. These parts, which in the 'present embodiment are all rotationally stationary, may'be said to constitute one of the major components of the engine.

Rotatably mounted within the casing struc ture on suitable bearings I8 and 28 (Fig; 3) is the second major component of the engine consisting of a cylinder bank formed by a plurality of radially arranged cylinders 22 (of which there are seven in the present embodiment) secured to a crank case structure 24' carried by the bearings l8 and 28. While for simplicity of illustration only one cylinder bank has been illustrated, it will be understood that within the scope of the invention the engine may comprise a plurality of cylinder banks mounted in line one behind another.

Each of the cylinders 22 is provided with a suitable piston 24 and the piston of all of the cylinders of the bank are connected through any suitable arrangement of connecting rods, one of which is shown at 26in Fig. 3, to the crank pin 28 of a crankshaft 38 which may be considered as the third major component of the engine. Crankshaft 30 is mounted in suitable bearings for relative rotation with respect to both the cylinder bank and the stationary structure of the engine.

The several cylinders of the bank are open at their outer ends and have located therein sealing elements 32 of cuff-like form providing cylinder ports 34 through which gases are admitted to and exhausted from the cylinders as the cylinders pass the inlet ports and exhaust ports formed in the valve member. The position of the inlet ports is indicated at 36 on Fig. 2 and that of the exhaust ports at 38 on Figs. 2 and 3. The several ports in the valve member are closed when not in communication with a cylinder port by means of an annular sealing ring 40 carried by the cylinder bank and having suitable apertures therein through which the sealing elements 32 project. The specific form and arrangement of the sealing means between the ends of the cylinders and the valve member and also the combustion cycle of the engine are not material to the present invention and need not be described in detail herein for an understanding of this invention.

Referring now more particularly to Fig. 3, the power output shaft 42' of the engine, which shaft in the present embodiment may be considered as 8. fourth major component of the engine, is

mounted in alignment with the axis of rotation of the crank and is supported for relative rotation with respect to the crankshaft by means of a pilot bearing 44 in the front end of the crankshaft and abearing 46 carried by a front end plate 48 bolted to the stationary casing member I8 and forming a part of the stationary struc- I ture of the engine. The front end of the crankshaft has keyed or splined thereto an internal gear 58 meshing with a series of' planet pinions 52 carried on pins 54 which are in turn carried, in a planet carrier 58 of drum-like form, suitably apertured as shown in the lower portion of Fig. 3 to'permit the planets 52 to project into meshing contact with the crankshaft gear 58. The planet carrier 56 is fixed to the power shaft 42, advantageously by means of splines 58 on the carrier and on a disc-like flange 88 formed on the shaft. The planets 52 also mesh with a stationary gear 62, the mounting of which will be described more in detail later.

The cylinder. bank has fixed thereto a ring I by means of bolts 86 which also serve to retain.

a gear case member 88 which at its forward end is mounted on a bearing 18 to provide a support hereinafter more fully referred to.

Gear 64 meshes with a set of planet pinions 12 forming one part of a set of compound planets. the remaining part of which is formed by a set of planet pinions 14. The compound planets are mounted for rotation on pins Hi which, like the pins 54, are mounted in the planet carrier 58, and the part of the planet carrier in which the compound planets are mounted is provided with suitable apertures through which the planet pinions may project to mesh with their respective The pinions 14 mesh with a ring gear similar teeth or splines on an annular disc-like torque transmitting member 86 which at its outer periphery is clamped by means of bolts 88 to the stationary casing structure. Member 86 is made of elastic material such, for example, as Bakelite and is preferably designed with respect to its cross-sectional area so that the torque transmitted through the member will result in uniform unit stress therein. Materials other than Bakelite may be used for this member, the primary requisite of which is that the material shall be resilient and elastic in nature and at the same time of suflicient strength to transmit the 1'8! quired forces without distorting to an extent which will allow gears 62 and 18 to turn sufliciently to adversely effect the phase relation between the parts connected.

Advantageously, the hub portion 82a of the sleeve 82 is resiliently clamped between annular friction rings 98.and 92 which may advantageously be of Bakelite, these rings bearing on v the opposite side faces of the hub and exerting clamping pressure thereon by virtue of a series of rived from the above described gearing is as follows:

Upon rotation of the crankshaft of the engine, in counter-clockwise direction as viewed in Fig. 5, the crankshaft gear 50, rotating in the direction of the arrow llll in Fig. 5 causes the planets 52, which mesh with the stationary gear 82, (which for convenience of identification may be referred to as the inner stationary gear and which also is the sun gear of the planetary system including planets I! and crankshaft gear II) to rotate about their own axes in the direction of the arrow I02 and also to rotate in a circular path or orbit around the center of the gearing in the direction of the arrow I. The rotation of planets I2 in their orbital path causes the planet carrier to rotate in the same direc- "14 meshing with the stationary gear 18 (which may for convenience of identification be termed the outer stationary gear and which also is in effect the sun gear of the planetary system including the compound planets and the cylinder gear 64) are caused to move in an orbital path in the direction indicated by the arrow I in Fig. 5, and this orbital movement results in these pinions rotating about their own axes in the direction of the arrow I08. This rotation of pinions ll about their own axes, combined with the orbital movement imposed ,by the rotation of the planet carrier, causes the pinions 12, which mesh with the cylinder gear 84, to move in an orbital path indicated by arrow I I0 and to rotate about their own axes in the direction indicated by arrow H2. In the present embodiment,

pinions I2 are of larger diameter than pinions I4 and since the speeds of these two sets of pinions in their orbital paths and their speed of rotation about their own axes is the same, it will be evident that if the smaller pinion ll meshes with a stationary gear, as it does. the larger pinion 12 will impose on the gear with which it meshes a rotational movement in the direction of the arrow Ill. As viewed in Fig. 5, the assumed direction of rotation of the crankshaft gear 50 is' counter-clockwise as indicated by arrow Hill and the direction of rotation imposed by pinion 12 on the cylinder gear 84 is clockwise, as indicated by arrow 4., From a consideration of Fig. 5 it'will be apparent that ii the relative sizes of pinions 12 and I4 were to be reversed as compared with the relation shown in Figs. 3 and 5, and their respectivelyt gears correspondingly alteredin size, he direction of movement of the cylinder gear i4 imposed by the pinions 12 would be the reverse of that shown in Fig. 5 so that this gear would rotate in the same direction as the crankshaft gear. It will be thus evident that the gearing illustrated may be employed with equal facility to different kinds of birotary. engines in which the cylinders and crankshaft may rotate in opposite directions or in the same direction.

It is apparent that in any engine torque reaction must be transmitted between parts to which torque is applied in the generation of power or meshing because of. the delivery of power and the part or parts providing a mounting for the engine which parts may be said to provide or constitute a torque reaction absorbing abutment.

In the present engine, the reaction absorbing abutment is constituted by the stationary casing structure which is fixed against rotation and to which the net torque reaction from the power generating and delivering components of the engine must eventually be transmitted.

In the present form of engine, the cylinder bank, constituting one of the engine components, transmits torque reaction due to the side thrust of the pistons on the cylinders. This torque reaction is transmitted in the present instance through the cylinder gear and the planet carrier to the stationary gear 18. The net torque reaction from the power shafts, that is, the crankshaft 30 and the power output shaft 42, is transmited through the planet carrier to the stationary gear 82. Thus, it will be seen that all torque reaction between the several components of the engine is eventually transmitted through either gear 82 or gear "I8 to the sleeve 82. Variations in the value of the net torque reaction will tend to cause this sleeve to vibrate but such vibration is, in accordance with the present invention, substantially absorbed by the resilience of the elastic torque reaction absorbing member '6 interposed between this sleeve member, in which all torque reaction is concentrated, and the stationary torque absorbing abutment provided by the stationary component of the engine.

In connection with this function of the member 86, it is particularly to be noted that one feature of construction in accordance with the present invention permits this member to be loaded in torsion only. As will be observed from Fig. 3, the inner race, of the bearing III is fixed to an annular disc-like stationary member 98 which at one end bears against the stationary sleeve 82 and at its other end is clamped to the stationary casing structure by the bolts 88. It will thus be seen that the weight of the cylinder bank is supported at the forward end of the engine by what is in effect a bridge construction consisting of the rigid gear case member 88, bearing 10 and member 96, which transmits the weight directly to the stationary casing structure. This evidently relieves the member 86 from the support of any of the engine weight so that the only stress imposed on this member is the torsional stress of the torque transmitted through it.

In any system in which vibrations occur, there is constant interchange of the form of the energy represented by the vibrations, from kinetic to static, and vice versa. This condition we have in the present instance in which the sleeve member 82 tends to vibrate due to variations in .the torque reaction transmitted to this member. The energy which is being constantly transformed back and; forth between the kinetic and static forms is, in effect, locked in the system and can be dissipated only by some form of damping means which will serve to absorb the energy. Such damping means is provided in the present instance by the friction rings Ill and 92 which lation of the sleeve 82 relative to the stationary engines, and some features of which may be employed to the exclusion of others. The invention is accordingly to be understood as embracing all forms of structure falling within the scope of the appended claims.

What is claimed is:

1. A birotary engine comprising a, plurality of major engine components having relative rotary movement with respect to each other and including a component fixed against rotation andcon-" stituting' the component by'which the engine is I mounted, and means for maintaining the rela-' tively moving components in desired phase rela-' tion including an elastic'connection in the path of torque transmission between the mounti component and the remainder of said compo- .nents. v r

2. A birotary engine comprising a plurality-of major engine components mounted for relative rotary movement with respect to each other and including a component fixed against rotation and constituting the component by which. the engine is mounted, and means including gearing for maintaining the relatively movingcomponents in desired phase relation, said means further including an elastic connection in the path of torque transmission between the mounting component and the remainder of said components.

3. In a birotary engine, a plurality of ma-Jorengine components having relative rotary movement with respect to each other, an engine component providing means for mounting the engine, gearing interconnecting said relatively rotating components, and elastic means for resiliently transmitting from said gearing to the mounting component the torque reaction from said relatively rotating components.

4. In a birotary engine, stationary casing structure including a valve member, a cylinder bank mounted for rotation relative to said valve memher, a crankshaft mounted for rotation relative to said valve member and said cylinder bank, and means including an elastic member for transmitting torque reaction from the rotating components to said casing structure.

5. In a birotary engine, stationary casing structure including a valve member, a cylinder bank mounted for rotation relative to said valve member, a crank shaft mounted for rotation relative to said valve member and said cylinder bank,

gearing connecting said cylinder bank and said crankshaft including a part required to be held rotationally stationary relative to said casing structure and to which torque reaction from the w rotating components is transmitted, and an elastic member for connecting said part to said casing structure. i

6. In a birotary engine, a plurality of major engine components having relative rotary movement with respect to each other including a rotationally stationary component providing means for mounting the engine, planetary gearing interconnecting said relatively rotating components, said gearing including a gear required to be held 15 rotationally stationary relative to the mountlns the engine, and means including gearing for main taining the desired phase'relation betweenthe i several components, said means iincludingan elastic connection in the path of torque-trans- -mission between the mounting component and each of the remainder of said components. v

8. In a birotary engine, a cylinder bank and a crankshaft mounted for'relative rotary'move ment, with respect to eachother, gearson said 7 members, stationary gears, a planet carrier carrying a plurality of sets of planets for connecting H each of the first mentioned gears with a station ary gear, stationary engine mounting structure including a valve member cooperating with the cylinders, and an elastic connection between said stationary structure and said stationary gears. 9. In a birotary engine, a cylinder bank and a' crankshaft mounted for relative rotary movement with respect to'each other,-gears on said members, a plurality of stationary gears, a planet carrier carrying a plurality of sets of planets for connecting each of the first mentioned gears respectively with a different one of said stationary gears, and a power output shaft driven by said planet carrier.

I 10. m a birotary engine, a cylinder bank and V a crankshaft mounted for relative rotary move ment with respect to each other,.gears on said members, stationary mounting structure, stationary gears, a planet carrier carrying a plurality of sets of planets for connecting each of 0 relative to crankshaft speed, and a second plane '0 tary gearing associated with said first gearing and including a second stationary gear providingaf gear connection between the crankshaft and the cylinder bank. I v

12. In a birotary engine, a rotatable cylinder bank, a rotatable crankshaft, and gearing for maintaining the cylinder bank and crankshaft in desiredpha s'e relation, said gearing comprising twointerconnected planetary gear systems each including a" stationary ge'ar andfsaid systems .0

having'a common planet carrier and one of said gear systems includingv compound planets;

13. In a'birotary engine, a rotatable cylinder bank, a rotatable crankshaft, gearing for maintaining the cylinder bankand crankshaft in del sired phase relation,}said'gearing'comprising two .1 1 smnn d pl pew r common planet carrier; each of. said systems sin-'- eluding astationary geanand elastic-means for connectingsaid stationary gears to a rotatably stationary part to prevent their rotation and to absorb variations in' torque reaction transmitted to said stationary gears.

14. In a birotary engine, a rotatable cylinder bank, a rotatable crankshaftfa'first planetary Tl s stems-savings gearing including a crankshaft gear, a stationary gear and a planet carrier carrying planets meshing with said gears, and a second planetary gearing including a second stationary gear, a cylinder gear and compound planets connecting the cylinder gear with said second stationary gear, said compound planets being carried by said planet carrier.

15. In a birotary engine, a plurality of rotatably mounted engine components including a cylinder bank and a crankshaft, a crankshaft gear forming the ring gear of a planetary gearing, a stationary gear forming the sun gear of said gearing, a planet carrier carrying a set of planets meshing with said gears, a cylinder gear forming the ring gear of a second planetary gearing, a second stationary gear, and a set of compound planets carried by said planet carrier each of said compound planets comprising two pinions of different size one of which meshes with said cylinder gear and the other of which meshes with said second stationary gear.

16. In a birotary engine, a plurality of rotatably mounted engine components including a cylinder bank and a crankshaft, a crankshaft gear forming the ring gear of a planetary gearing, a stationary gear forming the sun gear of said gearing, I a planet carrier carrying a set of planets meshing with said gears, a cylinder gear forming the ring gear of a second planetary gearing, a second stationary gear, and a set of compound planets carried by said planet carrier each of said compound planets comprising two pinions of different size, the larger of which meshes with the cylinder gear and the smaller of which mesheswith the second stationary gear.

17. A birotary engine comprising a plurality of major engine components mounted for relative rotary movement with respect to each other, one of said components fixed against rotation and constituting the component by which the engine is mounted, means including gearing for timing the relative rotary movement between the several components, said gearing including a member required to be held stationary, an elastic connection between said member and said stationary component, and means carried by said stationary component and frictionally engaging said memher to damp vibration thereof caused by variations in the torque reaction transmitted thereto.

18. In a birotary engine, a stationary engine component, a plurality of engine components adapted to rotate relative to each other and relative to said stationary component, bearings for transmitting the weight of the rotatable components to the stationary component, and means including gearing for maintaining said. components in desired phase relation relative to each other, said means including an elastic member interposed in the path of torque transmission between said stationary component and the rotatable components and said member being free of the weight of any of said components.

19. In a birotary engine having a. cylinder bank, a crankshaft and stationary structure for mounting the engine, a crankshaft ring gear, a sun gear, an elastic connection between said sun gear and said stationary structure, a planet carrier carrying a set of planets meshing with said gears, and a power output shaft connected to said planet carrier.

20. In a. birotary engine having a cylinder bank, a crankshaft and stationary structure for mounting the engine, a power output shaft in alignment with the axis of the crankshaft, a

crankshaft ring gear, a planet carrier carrying a set of planets meshing with said gear, an annular gear around said power output shaft and meshing with said planets, a driving connection between said planet carrier and said power output shaft, and an elastic connection between said annular gear and said stationary structure.

21. In a birotary engine, a front casing structure, a disk-like elastic torque transmitting member fixed to the forward part of said structure, a sleeve member secured to said torque transmitting member and extending rearwardly therefrom coaxially of the axis of the engine, a crankshaft, a cylinder bank, and gearing including gears on said sleeve member for causing said crankshaft and said cylinder bank to rotate in predetermined phase relation with respect to each other and to said casing structure.

22. In a birotary engine, a front casing structure, a disk-like elastic torque transmitting member fixed to the forward part of said structure, a sleeve member secured to said torque transmitting member and extending rearwardly therefrom coaxially of the axis of the engine, a. crankshaft, a cylinder bank, gearing including gears on said sleeve member for causing said crankshaft and said cylinder bank to rotate in predetermined phase relation with respect to each other and to said casing structure, a. power output shaft extending through said sleeve member, and a connection between said power output shaft and said gearing for driving the power output shaft at a speed lower than that of the crankshaft.

23. In a birotary engine, a stationary mounting structure, a rotatable cylinder bank, a rotatable crankshaft, gearing connecting said crankshaft and said cylinder bank for maintaining the cylinder bank and crankshaft in desired phase rela' tion with respect to each other, said gearing including a part required to be held stationary, and a disk-like member of elastic material providing a torque transmitting connection between said stationary structure and said part required to be held stationary, said member having different thicknesses at different distances from its center to provide uniform unit stress in the mem her due to torque transmission therethrough.

24. In a birotary engine, a stationary mounting structure, a rotatable cylinder bank, a rotatable crankshaft, gearing connecting said crankshaftand said cylinder bank for maintaining the cylinder bank and crankshaft in desired phase relation with respect to each other, said gearing including a part required to be held stationary, a disk-like member of elastic material providing a torque transmitting connection between said stationary structure and said part required to be held stationary, means for frictionally contacting the side faces of said disk-like member, and springs for resiliently maintaining said means in pressure contact with said faces.

25. In a birotary engine, stationary housing structure, a rotatably mounted cylinder bank,'a rotatably mounted crankshaft, a rotatably mounted power output shaft in alignment with the axis of rotation of the crankshaft, a crankshaft gear, a first stationary gear, a planet carrier carrying a set of planets meshing with said gears, means for connectingthe planet carrier to said power output shaft, a cylinder gear, a second stationary gear, a set of compound planets carried by said planet carrier, the pinions of said compound planets being of different size, a sleeve member around said power output shaft, said stationary gears being fixed to said sleeve member, a torque transmitting member of elastic material for connecting one end of said sleeve member to said stationary structure, and parts including a bearing providing a connection between said cylinder bank and said stationary structure for carrying the weight of the cylinder bank independently of said gearing, whereby to subject said elastic member to torsional stress only. 1

ANDRE J. MEYER.

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