Patent Publication Number: US-2016245167-A1

Title: Rotary oscillating internal combustion engine

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to rotary internal combustion engines and in particular, it concerns an oscillatory rotating internal combustion engine. 
     Oscillatory rotating engines, pumps and compressor are known in the art. Such devises employ a plurality of rotors with interleaved vanes rotating around a central shaft arrangement. By changing the relative angular velocity of the rotors an oscillatory movement is superimposed on their uniform rotation, thereby modifying the volume of energy chambers defined by each pair of adjacent vanes of the different rotors. Inlet and exhaust ports are provided at appropriate points such that expansion and contraction of the working chambers will provide induction, compression, expansion and exhaust strokes. The forces that alternately drive adjacent pistons apart or together are transformed through gear sets that drive the output shaft. 
     SUMMARY OF THE INVENTION 
     The present invention is an oscillatory rotating internal combustion engine. 
     According to the teachings of the present invention there is provided, a rotary oscillating internal combustion engine comprising: (a) an engine housing; (b) an external rotor assembly rotatably deployed within the engine housing; and (c) an internal rotor rotatably deployed within the external rotor assembly; wherein at least one spark plug is deployed on the external rotor assembly so as to rotate wherewith. 
     According to the teachings of the present invention, the external rotor assembly includes power grooves formed in the outer circumferential surface of the external rotor assembly such that there is one the power groove for each the spark plug. 
     According to the teachings of the present invention, each the power grove includes a non-conductive liner and a conductive strip. 
     According to the teachings of the present invention, there is also provided at least one valve actuator deployed on the external rotor assembly so as to rotate wherewith. 
     There is also provided according to the teaching of the present invention, a rotary oscillating internal combustion engine comprising: (a) an engine housing/stator; (b) an external rotor assembly rotatably deployed within the engine housing; and (c) an internal rotor rotatably deployed within the external rotor assembly; wherein at least one valve actuator is deployed on the external rotor assembly so as to rotate wherewith. 
     According to the teachings of the present invention, the valve actuator includes an axle shaft that extends through sides plates of the external rotor assembly 
     According to the teachings of the present invention, there is also provided a valve having a bulbous valve stem tip that engages an elliptical valve control groove formed in the valve actuator such that as the valve actuator rotates the bulbous valve stem tip traverses a path of the elliptical valve control groove and in doing so, the valve is displaced between an open and a closed position. 
     According to the teachings of the present invention, there is also provided at least one spark plug deployed on the external rotor assembly so as to rotate wherewith. 
     There is also provided according to the teaching of the present invention, a gear set for use with a rotary oscillating device, the gear set comprising: (a) a first lobed drive gear associated with an external rotor assembly so as to rotate at a same oscillating rotational speed as the external rotor assembly; (b) a second lobed drive gear associated with an internal rotor so as to rotate at a same oscillating rotational speed as the internal rotor; and (c) a pair of driven gears rigidly connected together and to an output shaft so as to rotate at the same angular velocity, the pair of driven gears being driven by the first and second drive gears, the pair of driven gears being rigidly connected to an output shaft; wherein the first and the second drive gears and each one of the pair of driven gears all have the same size, shape and number of teeth. 
     According to the teachings of the present invention, each of the first and the second drive gears and each one of the pair of driven gears has at least one maximum point and at least one minimum point corresponding to at least one power stroke. 
     According to the teachings of the present invention, the at least one maximum point and at least one minimum point are configured as one of two, three, four, five and six maximum points and minimum points, corresponding to one of two, three, four, five and six power strokes per engine revolution respectively. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein: 
         FIG. 1  is an exploded drawing of  2  stroke oscillatory rotating internal combustion engine constructed and operational according to the teaching of the present invention, shown here with a  4  vane inner rotor,  8  combustion chamber outer rotor, gear drive sets and induction and exhaust components; 
         FIG. 2  is a longitudinal cross section of the engine of  FIG. 1 ; 
         FIG. 3  is a transverse cross section of the engine of  FIG. 1 ; 
         FIG. 4  is an isometric view of the outer rotor and intake and exhaust discs the engine of  FIG. 1 ; 
         FIG. 5  is a cross section of the outer rotor the engine of  FIG. 1 ; 
         FIG. 6A  is an isometric view of the outer rotor the engine of  FIG. 1 , here showing electrical contact strips on the outer edges; 
         FIG. 6B  is a detail of  FIG. 6A ; 
         FIG. 7  is a transverse cross section of the outer rotor the engine of.  FIG. 1 ; 
         FIG. 8  is an isometric cut-a-way view of an alternative valve arrangement, constructed and operational according to the teaching of the present invention, for use with a modified embodiment of the engine of  FIG. 1 ; 
         FIGS. 9 and 10  are details of the alternative valve arrangement of  FIG. 8 ; 
         FIG. 11-13  are isometric side views of two variations of drive configurations for the alternative valve arrangement of 8; 
         FIGS. 14A-19B  are diagrams of work cycle of one possible embodiment of an oscillatory rotating internal combustion engine constructed and operational according to the teaching of the present invention, illustrated here with a single vane inner rotor, twin combustion chamber outer rotor, producing two power strokes per shaft revolution and corresponding drive and driven gear pairs&#39; rotation; 
         FIG. 20  is a drawing of eccentric elliptical gear geometry for an engine having one power stroke per revolution; 
         FIG. 21  is a drawing of concentric elliptical gear set geometry for an engine having two power strokes per revolution; 
         FIG. 22  is a drawing of concentric three lobe gear set geometry for an engine having three power strokes per revolution; 
         FIG. 23  is a drawing of concentric four lobe gear set geometry for an engine having four power strokes per revolution; 
         FIG. 24  is a drawing of concentric five lobe gear set geometry for an engine having five power strokes per revolution; and 
         FIG. 25  is a drawing of concentric six lobe gear set geometry for an engine having six power strokes per revolution. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is an oscillatory rotating internal combustion engine. 
     The principles and operation of an oscillatory rotating internal combustion engine according to the present invention may be better understood with reference to the drawings and the accompanying description. 
     By way of introduction, a principal object of the invention is to provide a rotary piston apparatus employing two concentric rotating members and a centrally located, eccentrically mounted, coupling means between the two members to create compression and/or expansion power strokes for applications to pumps, compressors and internal combustion engines. 
     The oscillatory rotating internal combustion engine of the present invention provides one or more combustion chambers per rotor for varying possible power output. 
     It should be noted that the oscillatory rotating internal combustion engine of the present invention may be configured as either a 2 stroke or 4 stroke engine. 
     The oscillatory rotating internal combustion engine of the present invention also provides two pairs of elliptical and eccentrically rotating gears for maintaining a varying rotational speed ratio between the two rotating rotors and produce continuous rotational speed of power transmission trough a common output shaft. 
     The design of the oscillatory rotating internal combustion engine of the present invention further provides minimal acceleration and deceleration of said rotors, relative to engine case, so as to reduce vibration and force loads on the engine or pump. 
     The oscillatory rotating internal combustion engine of the present invention may be configured so as to perform a variety of the number of work cycles per output shaft revolution. 
     The oscillatory rotating engine of the present invention employs a circular housing in which, a pair of rotors with a plurality of interleaved vanes, revolves around the center of rotation. By changing the angular velocity of the rotors an oscillatory movement is introduced into their uniform rotation, thus modifying the volume of combustion chambers defined by one face a vane and the corresponding inner surface of the outer rotor. Inlet and exhaust are provided at appropriate points on side faces of outer rotor, while spark plugs deployed on the circumferential outer wall of the outer rotor, so that expansion and contraction of the working chambers will provide induction, compression, power and exhaust strokes. Oscillating power pulses produced are transformed to continuous power flow that drives the output shaft by means of two pairs of lobed gear sets of various possible shapes. Each pair of lobed gears has the same size, shape and number of teeth. Driven gears are rigidly connected together and rotate at the same angular velocity. Drive gears are rigidly connected to inner and outer rotors and rotate with said rotors. Relations and shapes of drive gear sets are directly related to number of combustion chambers and number of power strokes per rotors revolution. 
     Referring now to the drawings,  FIGS. 1-10  illustrate the structure of a preferred embodiment of the oscillatory rotating internal combustion engine of the present invention. An external rotor assembly  10  and internal rotor  2  are rotatably mounted in engine housing  5   
     External rotor assembly  10  is rigidly attached to external rotor drive gear  10 A and internal rotor  2  is rigidly attached to internal rotor drive gear  2 A. Two driven gears,  108  and  2 B are rigidly attached to output shaft  13  which is rotatably mounted in engine housing  5 , parallel to rotors  1  and  2  and rotates opposite to said rotors direction of rotation. 
       FIGS. 4-7  show the external rotor assembly  10  comprising external rotor  1 , intake disc  4 , incorporating a circular plate with intake ports  4 A and concentric hollow cylindrical protrusion  48 , exhaust disc  3 , incorporating a circular plate with exhaust ports  3 A and concentric hollow cylindrical protrusion  3 B. Exhaust disc  3  and intake disc  4  are concentrically and rigidly attached to respective side faces of external rotor  1 . Cylindrical shaped protrusions  3 B and  4 B are axially aligned and form external rotor  1  axis of rotation. 
     External rotor  1 , as best illustrated in  FIG. 5 , is substantially ring shaped with plurality of radially arranged cutouts  1 A forming the equivalent of reciprocating engine cylinders. Concave depressions  1 B on radial faces of cutouts  1 A form the engine combustion chambers with sparkplugs  1 C mounted in threaded bores  1 D (best seen in  FIG. 6A ). 
     It will be readily appreciated that one unique feature of the present invention is that the spark plugs  1 C are mounted on, and rotate with, the external rotor assembly  10 . In order to provide the necessary electrical connection to the rotating spark plugs  1 C, power grooves  100  are formed in the outer circumferential surface of the external rotor assembly  10  such that there is one power groove  100  for each spark plug  1 C. As best illustrated in  FIG. 6B , each power grove  100  includes a non-conductive liner  102  and a conductive strip  104 . It will be understood the corresponding brushes are configured on the inner surface of the stator segment  5 A of engine housing  5  and that conventional style spark plug wires may be employed to connect each of the power grooves  100  to a corresponding spark plug. It will be appreciated that the number of spark plugs  1 C and therefore the number of power grooves  100  may be varied according to the design requirements of a particular engine application. 
     Internal rotor  2  includes a cylindrical center portion with at least one radial protrusion  2 A, serving as piston, and an axial protruding shaft  2 B which rotates inside protrusions  3 B and  4 B of external rotor assembly  10 . 
     Exhaust side cover  9  is a circular, dish shaped cover, incorporating bearing housing  9 A, cooling slots  9 B and exhaust manifold opening  9 C. The exhaust cover  9  is concentrically and rigidly attached to the exhaust side face of engine housing  5 . 
     Intake side cover  8  is double circular shaped cover, incorporating bearing housing  8 A and intake manifold opening  8 B. The intake cover  8  is concentrically and rigidly attached to intake side face of engine housing  5 . 
     External rotor assembly  10  rotates in bearings  11  mounted in bearing housings  9 A and  8 A. 
     Engine housing  5  includes a ring shaped stator segment  5 A, in which the external rotor assembly  10  and the internal rotor  2  rotate, and disc shaped element having round tube  5 B and bearing housings  5 C, for bearings  12 , in which output shaft  13  rotates. 
     Intake manifold  6  includes a longitudinal sliced toroidal shaped ring and tangentially connected intake pipe  6 A. The intake manifold  6  is rigidly and concentrically attached to intake cover  8 . 
     Exhaust manifold  7  comprises a longitudinally sliced toroidal shaped ring and tangentially connected exhaust pipe  7 A. The exhaust manifold is rigidly and concentrically attached to exhaust cover  9 . 
       FIGS. 14A-19B  illustrate the engine phase cycle of the preferred embodiment of a two stroke work cycle of the oscillatory rotating internal combustion engine of the present invention. The drawings refer to a one vane  2 A internal rotor  2  and one chamber  1 A external rotor  1  with work cycles alternating in both sides of internal rotor vane  2 A, producing one work phase per internal rotor vane side, per rotors revolution. Intake and exhaust ports  4 A and  3 A respectively are at opposite sides of rotor  1  and are shown superimposed. The number of internal rotor vanes and power chambers can be increased to any desirable and practical number. 
       FIG. 14A  shows the relative position of the external rotor assembly  10  and the internal rotor  2  in which internal rotor vane  2 A is in Top Dead Center (TDC) for combustion chamber  1 D and at Bottom Dead Center (BDC) for combustion chamber  1 E. Air fuel mixture is drawn to chamber  1 E through port  4 A. At this stage a spark is introduced in chamber  1 D and work phase starts. 
     Corresponding drive gear positions are illustrated in  FIGS. 14B, 15B, 16B, 17B, 18B and 19B . 
       FIG. 15A  shows chamber  1 D in work phase and chamber  1 E at the end of the intake and exhaust phases where intake and exhaust ports  3 A,  4 A are closed by internal rotor vane  2 A. It should be noted that at this stage internal rotor  2  rotates faster than external rotor  1 , thus producing power/compression strokes at opposite sides of vane  2 A. 
       FIG. 16A  shows combustion chamber  1 D at end of power stroke and chamber  1 E during compression stage, prior to ports  3 A,  4 A being exposed by vane  2 A. 
       FIG. 17A  shows the relative position of the external rotor assembly  10  and the internal rotor  2  where internal rotor vane  2 A is in Top Dead Center (TDC) for combustion chamber  1 E and at Bottom Dead Center (BDC) for combustion chamber  1 D. Air fuel mixture is drawn to chamber  1 D through port  4 A and burnt gases expelled through opposite exhaust port  3 A. At this stage a spark is introduced in chamber  1 E and a work phase starts. At this point the relative rotational speed of the external rotor assembly  10  and the internal rotor  2  alternates due to gear set geometry and internal rotor  2  rotates slower than external rotor  1 , thus reversing power/compression strokes at opposite sides of vane  2 A. 
       FIG. 18A  shows chamber  1 E in work phase and chamber  1 D at end of intake and exhaust phases where intake and exhaust ports  3 A  4 A are closed by internal rotor vane  2 A. 
       FIG. 19A  shows combustion chamber  1 E at end of power stroke and chamber  1 D during compression stage, prior to ports  3 A,  4 A being exposed by vane  2 A. After completion of this stage, rotors  1  and  2  have completed one revolution comprising one power stroke for each side of internal rotor vane  2 A. Drive gears  10 A and  2 A, which rotate at alternating speeds, also complete one revolution and transmit alternating power pulses to gears  28  and  10 B, which rotate at constant speed. 
     It will be understood that during the above described work cycle, compressed air and fuel mixture is fed to inlet ports  4 A through intake manifold  6  which is stationary but fits closely to intake plate  4 . Scoops  4 C, located in intake plate  4 , aid in directing air fuel mixture to inlet ports  4 A. Burnt gases are expelled through exhaust manifold  7 , aided by centrifugal effect produced by scoops  3 B placed on exhaust plate  3 . 
     Referring back to  FIGS. 8-13 , which illustrate an alternative valve configuration for use in a four stoke embodiment of the oscillatory rotating engine of the present invention. As illustrated here, intake port  3 A and exhaust port  4 A are replaced with more conventional four stoke valve  200  having a valve stem  202  that extends such that the valve seat  204  closes an opening in the concave depression  1 B on radial faces of cutouts  1 A of the engine combustion chambers and a bulbous valve stem tip  206 . 
     The valves  200  are operated between an open and closed position by a valve actuator  210  that is rotatably mounted on the external rotor assembly  10 . It will be understood that the valve actuator  210  includes an axle shaft (now shown) that extends through the exhaust plate  3  and the intake plate  4  which form the side plates of the external rotor assembly  10 . 
     It will be readily recognized that this valve assembly does not include valve lifters as is the current industry standard. The bulbous valve stem tip  206  of valve stem  202  engages the modified-elliptical valve control groove  212  of the valve actuator  210  such that as valve actuator  210  rotates bulbous valve stein tip  206  traverses the path of the modified-elliptical valve control groove  212 . In doing so, valve  200  is displaced between an open and a closed position in a substantially continuous reciprocating motion while the oscillatory rotating engine of the present invention is running. That is to say, the valve  200  is pushed and pulled by the valve actuator  210 . It will be appreciated that the illustration of a modified-elliptical valve control groove is used here only as a non-limiting example and that the valve control groove may be configured with substantially any contour dependent on the valve displacement requirements of a particular design embodiment of an oscillatory rotating internal combustion engine of the present invention. It should be noted that, although not illustrated here, the use of a spring mechanism to force the valve  200  toward a closed position so as to enhance the sealing of the valve seat  204  for better performance of oscillatory rotating internal combustion engine of the present invention. 
     It will be readily appreciated that valve actuator  210  may be configured with substantially any number of elliptical valve control grooves so as to operate an appropriate number of valves as require by a particular engine design. 
     In its simplest embodiment, rotation of the valve actuator  210  is achieved by the interaction of a first gear rigidly attached to at least one end of the axle shaft of valve actuator  210  and a stationary second gear attached to the stator segment  5 A of engine housing  5 . 
     As illustrated in  FIGS. 11-12B , rotation of the valve actuator  210  is achieved by the interaction of a plurality of gears, a set of four first gears  220  rigidly attached to the end of the axle shaft of valve actuator  210 , a set of four intermediate rotation speed adjusting gears  222  and a stationary drive gear  224  attached to the stator segment  5 A of engine housing  5 . It will be appreciated that intermediate rotation speed adjusting gear  222  is configured so as to interact with first gear  220  via a first gear face  222   a  and with stationary drive gear  224  via a second gear face  222   b.  The ratio of the change of rotation speed is determined by the ratio of the size and/or number of teeth between the first gear face  222   a  and the second gear face  222   b.  Such a drive arrangement will be readily understood by one of skill in the art. 
     Alternatively, as illustrated in  FIG. 13  rotation of the valve actuator  210  is achieved by the interaction of a stationary drive gear  224  attached to the stator segment  5 A of engine housing  5 , a single intermediate rotation speed adjusting gear  222 , a set of four first gears  220  rigidly attached to the end of the axle shaft of valve actuator  210  one of which ( 210   a ) is operationally rotated via the single intermediate rotation speed adjusting gear  222  and the rotation is transferred to the other first gears  220  via a drive belt  228 . It will be appreciated that drive belt  228  may alternatively be implemented as a drive chain. Here too, such a drive arrangement will be readily understood by one of skill in the art. 
     Attention is now directed toward the drive linkage of the oscillatory rotating engine of the present invention. The rotary oscillating engine drive linkage has two roles: 
     A. Transmit and combine external and internal rotors oscillating, pulsing revolutions into a continuous and smooth rotation at the output shaft. 
     B. Govern acceleration and deceleration rates of said rotors while maintaining a continuous rotation without stops or reverse rotation, therefore reducing loads on engine components and smoothing out power output. 
     Generally speaking, drive gears  10 A and  2 A and driven gears  10 B and  20  are identical in size, shape and number of teeth and therefore complete one revolution simultaneously. It will be appreciated that the gear shape is directly related to number of engine power pulses per output shaft revolution. With that in mind, attention is directed to specific examples as illustrated in  FIGS. 20-25 . 
       FIG. 20  illustrates elliptical shaped gears with center of rotation offset to ellipse geometrical focus  20 ; said gear has one maximum point  23  and one minimum point  25  and thus produces one power pulse per rotors revolution. Size proportion between  20 - 23  and  20 - 25  determine the length of power stroke. Driven gears  100  and  2 B are rigidly attached to output shaft  13  at an angle of 180 degrees relative to each other thereby translating the variable relative speed between drive gears  10 A and  2 A, which are generated by the power and exhaust strokes of external rotor  10  and internal rotor  2 , into the constant rotational speed of output shaft  13 . It will be appreciated that the term “maximum point” is used herein to refer to a point of the circumference of the gear that is at the maximum distance from the center point of the gear. Likewise, the term “minimum point” is used herein to refer to a point of the circumference of the gear that is at the minimum distance from the center point of the gear. 
       FIG. 21  depicts elliptical gears with center of rotation at center of ellipse and driven gears fixed at 90 degrees relative to each other. This setup provides gears with two maximum points  25  and two minimum points  26 , thus producing two power strokes per rotors revolution. 
       FIGS. 22-25  illustrate drive gears sets with three, four, five and six maximum points  25  and minimum points  26 , providing three, four, five and six power strokes per rotors revolution respectively. The number of extremity points can be increased to any practical number in order to increase the number of power strokes per rotors revolution. Relative fixed angle between driven gears proportionally decreases with increase in gears number of maxima and minima points. Relative length difference between radial distances of extremity points in each gear set determines piston stroke angular distance and thus displacement. 
     It will be appreciated that the above descriptions are intended only to serve as examples and that many other embodiments are possible within the spirit and the scope of the present invention.