Patent Publication Number: US-3875905-A

Title: Rotary engine and drive gearing therefor

Description:
United States Patent Duquette Apr. 8, 1975 ROTARY ENGINE AND DRIVE GEARING [57] ABSTRACT THEREFOR A rotary engine is provided with a four-lobed chamber 7 lnvemur; Gagmn Duquem, 2 Fem Saint containing a five-sided rotor arranged to provide two Eustache Quebec Canada explosions for each side of the rotor, namely 10 explosions for each revolution of the rotor so as to obtain [22] F&#39;ledi 1973 greatly increased power and greater smoothness of op- Appl. No.: 338,984  
 [52] US. Cl l23/8.45; 4l8/6l A [5 l] Int. Cl. F02b 55/14 [58] Field of Search 4l8/6l A; 123/845. 8.0]; 74/802. 804; 82/l.3  
 [56} References Cited UNITED STATES PATENTS 3,2l3,7l4 lU/l965 Hejj et al. 418/61 A 3216.405 l1/l965 .lungbluth 4l8/6] A 3,244,l55 4/l966 Laudet l23/8.45 3.260,]35 7/l966 E.iscnhardt.... HS/6| A 3.587.534 6/1971 Weichclt 4l8/6l A 1744,94] 7/[973 Nestor 418/6] A Primary. E.\&#39;aminerC. J. Husar Assistant Examiner-Leonard Smith Attorney. Agent, or FirmBacon &amp; Thomas eration for approximately the same size of engine as a conventional rotary engine. There is further disclosed gearing for guiding the rotor in a path where its corners are constantly in contact with the chamber walls and for transmitting movement of the rotor to a drive shaft, which gearing is applicable to a rotor having any number of sides. Such gearing comprises an internal gear on the rotor concentric therewith, two pinions meshing with the internal gear at diametrically opposite points thereof, the pinions being eccentrically mounted on axes fixed with respect to the chamber, the internal gear having as many times the number of teeth of each of the pinions as there are faces on the rotor, and means connecting the pinions to the drive shaft preferably consisting of pinions rigid with the eccentric pinions and coaxially rotated therewith but concentric to the aforementioned axes of rotation and a gear concentric with and secured to the drive shaft and meshing with the concentric pinions.  
 10 Claims, 8 Drawing Figures PMENIEBAPR BISYS 3.875.905  
 SHEETIDFZ FIG.  
 PATENIEUAPR BIQYS 3 75 905 sum 2 q g ROTARY ENGINE AND DRIVE GEARING THEREFOR The present invention relates to rotary engines of the type having a chamber with a number of lobes and a rotor which revolves within the chamber in an eccentric path such that the corners of the rotor are in constant contact with the walls of the chamber. As the rotor moves within the chamber, each face thereof defines, with successive lobes, spaces acting successively as chambers in which the cycles of engine operation, namely intake compression, combustion and exhaust, take place. Engines of this type give improved performances compared with conventional piston type internal combustion engines of the same weight and they operate with less vibration due to the absence of reciprocating parts. Such engines furthermore are simpler in construction than comparable reciprocating piston engines because no valves, connecting rods and cam shafts are required even for four-cycle operation. I  
  Rotary engines of this type having a three-sided rotor and a two-sided chamber are well known and currently in production. It has also been proposed to provide a four-sided rotor revolving in a three-sided chamber. It is an object of the present invention to provide a rotary engine in which the rotor has a still greater number of sides and wherein each side forms a combustion chamber more than once during each rotor revolution. Better performance for a given engine weight and improved smoothness of operation is thereby obtained as compared to conventional rotary engines.  
  The invention accordingly provides a rotary engine comprising a chamber having four lobes, a five-sided rotor in the chamber, diametrically opposite ignition means at two junctures of the lobes, opposite intake ports in the lobes which trail each ignition means in the direction of rotation, the intake ports being remote from the ignition means, opposite exhaust ports in the lobes which lead each ignition means in the direction of rotation, the exhaust ports being remote from the ignition means, a drive shaft centrally in the chamber and gearing connecting the drive shaft to the rotor. In this arrangement, each of the five sides of the rotor forms an explosion chamber twice for each revolution of the rotor so that ten explosions altogether occur during each revolution of the rotor as compared with three explosions in the conventional three-sided rotor arrangement.  
  Further according to the invention, the gearing includes a gear on the rotor, opposite pinions meshing with the rotor gear, the pinions being eccentrically mounted on axes fixed with respect to the chamber and gearing connecting the pinions to the drive shaft. The result of this arrangement is that the rotor is revolved in its path in a positive fashion without relying for its positioning upon contact of the corners thereof with the chamber, as is the case in the conventional drive systems provided between the rotor and the drive shaft. As a result, the contact pressure of the corners of the rotor against the walls of the chamber is even throughout the operation of the engine, which prevents excessive wear of the chamber walls and of the corners of the rotor or sealing members provided at such corners.  
  Further according to the invention, the gearing connecting the pinions to the drive shaft comprises pinions rigid with the eccentric pinions coaxially rotated therewith but concentric with respect to the aforementioned axes and a gear concentric with and secured to the drive shaft meshing with the concentric pinions. This arrangement has the advantage of providing a balanced drive on the drive shaft and preventing the continuous lateral stresses which are imposed on the drive shaft in the conventional arrangements. As a result, there is less wobble of the drive shaft and less wear on the bearings in which it is mounted.  
  Further according to the invention, the rotor gear is an internal gear provided with five times the number of teeth of one of the eccentric pinions, which positively guides the rotor in its revolutionary path within the chamber.  
  Further according to the invention, the drive shaft gear may be either a sun gear or an internal gear. In the first case, the drive shaft will rotate in a direction opposite to the rotation of the rotor while in the second case, the drive shaft will rotate in the same direction as the rotor.  
  Further according to the invention, each eccentric pinion is preferably provided with the same number of teeth as each concentric pinion and the drive shaft gear has an integral number of times as many teeth as one of the pinions.  
  A further object of the invention is the provision of gearing associated with the rotor and the drive shaft which is applicable to a rotor having any number of sides.  
  Accordingly, in a rotary engine having a chamber, a rotor in the chamber having corners coinciding with the corners of a regular polygon of n sides, and a drive shaft, the invention provides the improvement comprising gearing for guiding the rotor in a path where its corners are constantly in contact with the chamber walls and for transmitting movement of the rotor to the drive shaft, the gearing comprising an internal gear on the rotor concentric with the polygon, two pinions meshing with the internal gear at diametrically opposite points thereof, the pinions being eccentrically mounted on axes fixed with respect to the chamber, the internal gear having 11 times as many teeth as each of the pinions, and connecting means between the pinions and the drive shaft.  
  Further according to the invention, counterweights are mounted on the eccentric pinions, excentric with respect to the aforementioned axes in a direction op possite the eccentric pinions so as to minimize the vibrations due to the eccentric pinions.  
  Preferred embodiments of the invention are illustrated by way of example in the accompanying drawings in which FIG. 1 is a cross-section of a rotary engine according to the invention;  
  FIG. 2 is a longitudinal section taken on line 2-2 of FIG. 1;  
  FIG. 3 is a longitudinal section similar to FIG. 2 showing a modified embodiment;  
  FIGS. 4 to 8 are diagrammatic cross-sections corresponding to FIG. 1 showing five sequential positions of the rotor.  
  Referring to FIGS. 1 and 2, the rotary engine comprises a block 10 closed on either side thereof by face plates 12 and 14. The block 10 has in the interior thereof a chamber with four lobes of equal size and evenly disposed about the center of the chamber. The lobes are designated in sequential clockwise direction as I, II, III and IV.  
  Diametrically opposite ignition means such as spark plugs 16 and 18 are provided at the junctions of lobes l-II and III-IV respectively.  
  A rotor 20 is mounted within the chamber of block 10. The rotor 20 has five sides designated respectively A-B-C-D and E in clockwise sequence, each side being slightly outwardly convex and provided with a concave central recess 22. The corners of rotor 20 at the junc ture between adjacent sides are provided with sealing members 24. These corners coincide with the corners of a regular pentagon.  
  The chamber lobes l and III which trail the spark plugs 16 and 18 respectively in the direction of rotation of the rotor as indicated by an arrow in FIGS. 4 to 8, are provided at portions thereof remote from the spark plugs with intake ports 2628 connected to a carburator or a fuel injection system (not shown). The lobes II and IV which lead spark plugs 16 and 18 respectively in the direction of rotation are provided remote from the spark plugs with exhaust ports 30-32 connected to an exhaust system (not shown).  
  A drive shaft 34 is mounted on bearings 36-38 secured to the face plates 12 and 14 respectively. The axis of drive shaft 34 is central with respect to the chamber in the interior of block 10. Rotor 20 is provided with an internal gear 40 concentric with the polygon defining the corners of the rotor 20. Internal gear 40 meshes with two diametrically opposite pinions 42 rigidly affixed on shafts 44 mounted for rotation on face plates 12 and 14. The pinions 42 are eccentric with respect to shafts 44 to the same degree and in the same direction. Shafts 44 also carry rigidly thereon diametrically opposite pinions 46 which are concentric with shafts 44 and mesh with a sun gear 48 concentric with and mounted on the drive shaft 34.  
  Shafts 44 also carry rigidly thereon adjacent eccentric pinions 42, eccentrically mounted counterweights 50 disposed in opposite direction from the eccentric pinions 42.  
  In the modified embodiment of FIG. 3, the sun gear 48 is replaced by an internal gear 48&#39; disposed beyond plate 14&#39; in a recess of an additional plate 52. Shafts 44&#39; extend beyond plate 14&#39; and carry concentric pinions 46 meshing with internal gear 48&#39;. The arrangement is otherwise identical to that of FIGS. 1 and 2.  
 OPERATION The internal gear 40 of the rotor is provided with as many times the number of teeth of each pinion 42 as there are sides to the rotor 20. Thus in the illustrated embodiment, the internal gear 40 has times the number of teeth of each pinion 42. For example, if each pinion has nine teeth, the internal gear has 45 teeth. The effect of the eccentric arrangement of pinions 42 is to revolve the rotor within the engine chamber while at the same time causing five lateral shifts of the rotor center such that the corners of the rotor follow the internal wall of each of lobes I, II, III and IV. These movements of the rotor are positive and the fact that the shafts 44 are fixed prevents any straying of the rotor from its determined path. The engine chamber is so designed that the lobes I, II, II and IV are in precise coincidence with the curves generated by the corners of rotor 20 during the above-described movement. As a result, not only the corners of the rotor and the sealing members 24 maintain continuous contact with the walls of the chamber lobes, but the pressure of the sealing members 24 on the chamber wall is constant throughout because the rotor 20 is entirely guided by the eccentric gear arrangement and the walls of the chamber do not play any factor in guiding the rotor. As a result, wear of the sealing members 24 and of the chamber walls is minimized.  
  The cycle sequence is illustrated in FIGS. 4 to 8. The various chambers in which the cycles of engine operation take place are defined in these figures with respect to the sides of the rotor.  
  In FIG. 4, side A is at the end of intake, chamber B is at the beginning of exhaust, side C is at intermediate intake, side D is at full compression at the beginning of combustion and side E is at intermediate exhaust. As the rotor advances to the position of FIG. 5, side A is at intermediate compression, B at intermediate exhaust, C at intermediate further advanced intake, D at intermediate combustion and E at the end of exhaust and beginning of intake.  
  In FIG. 6, side A has proceeded to the end of compression, B is at intermediate exhaust, C is near the end of intake, D is at the end of combustion and beginning of exhaust and E is at intermediate intake.  
  In FIG. 7, side A is at the beginning of combustion, B near the end of exhaust, C near the end of intake, D at intermediate exhaust and E at intermediate intake.  
  In FIG. 8, side A is at intermediate combustion, B is near the end of exhaust, C is at the end of intake and beginning of compression, D is at intermediate exhaust and E is at intermediate intake. The next position in the cycle is again that shown in FIG. 4 with the exception that side A now occupies the position of side B, B that of chamber C and so on in clockwise direction.  
  By following a single side, for example chamber A through the illustrations of FIGS. 4 to 8, it will be seen that the side goes through intake in FIG. 4, compression in FIG. 5 and 6, combustion in FIGS. 7 and 8 and subsequently exhaust through the exhaust port 30. Upon further revolution of the rotor, the side A will take in a charge of combustion gas through port 28, compress the combustion gas which will be ignited by spark plug 18 and after combustion has taken place, the spent gas will be exhausted through port 32 and the chamber adjacent side A will again be filled with combustion gas through port 26 as shown in FIG. 4. During each revolution of the rotor 20 therefor, each side undergoes two full four cycle sequences each including an explosion. There will therefore be IO explosions for.  
 each revolution of the rotor. It will also be seen that the explosions at the spark plug 16 are out of phase with.  
 the explosions of spark plug 18 so that the 10 explosions are evenly distributed in time for each revolution of the rotor 20. The fact that It) explosions are provided improves the performance of the engine and the smoothness of operation thereof. The fact that the explosions are staggered further improves smoothness of operation.  
  Revolution of the rotor 20 communicated to the eccentric gears 42 produces even speed rotation of shafts 44, which rotation is communicated through concentric pinions 46 or 46&#39; to the sun gear 48 or the internal gear 48&#39; producing rotation of shaft 34. The difference in the embodiments of FIGS. 2 and 3 is that in the embodiment of FIG. 2, the drive shaft 34 is rotated in upposite direction with respect to the rotor 20 while in the arrangement of FIG. 3, the drive shaft 34 rotates in the same direction as the rotor 20.  
  To insure proper timing of the sparking of spark plugs 16 and 18, the pinions 46 or 46&#39; have the same number of teeth as the pinions 42 and the sun gear 48 or sun gear 48 has a number of teeth which is an integral number of times the teeth provided on pinions 46. Thus for example, in the embodiment of FIG. 2, the sun gear 48 may have 3 times the number of teeth of the pinions while in the embodiment of FIG. 3, the internal gear 48 may have 5 times the number of teeth of pinions 46&#39;. As a result, the drive shaft 34 undergoes an integral number of rotations for an integral number of rotations of rotor 20 and the operation of spark plugs 16 and 18 may be controlled from shaft 34 through a conventional distributor (not shown).  
  Further to the above-defined advantages, the arrangement according to the invention also provides more rapid and uniform cooling of the chamber and rotor due to more frequent entry of combustion gas, less friction, less need for lubrication, a more silent operation as well as more complete combustion resulting in less emission of pollutants.  
  The purpose of recess 22 is to provide communication of chamber portions on either side of the spark plugs so that the whole compressed charge is ignited simultaneously as illustrated in FIG. 7.  
  Various modifications of the engine are possible within the scope of the invention. Thus, two of the lobes may be used for engine purposes while the other two lobes may be used as a compressor or turbo charger or one of the two remaining lobes may be used as a compressor and the other as a turbo charger.  
  With suitable modifications, the structure according to the invention may also be used as a hydraulic pump or a compressor or both or as a water pump.  
  Lubrication may be effected by forced circulation including filtering or by a mixture of oil and gasoline as in conventional two cycle engines. Furthermore, the spark plugs may be eliminated for diesel operations or replaced by glow plugs, and a fuel injection system added.  
  Cooling of the engine may be effected by circulating a fluid through appropriate passages in the block or by the combined action of air supplied by a fan or by movement of the vehicle, together with the cooling effect of a lubricating mixture of oil and gasoline.  
 I claim:  
  1. In a rotary engine having a chamber, a rotor in said chamber having corners coinciding with the corners of a regular polygon of n sides and a drive shaft; the improvement comprising gearing for guiding said rotor in a path where its corners are constantly in contact with the chamber walls and for transmitting movement of said rotor to said drive shaft, said gearing comprising an internal gear on said rotor concentric with said polygon,  
 two pinions meshing with said internal gear at diametrically opposite points thereof, said pinions being eccentrically mounted on axes fixed with respect to said chamber,  
 said internal gear having n times as many teeth as each of said pinions and connecting means between said pinions and said drive shaft.  
  2. In a rotary engine according to claim 1, counterweights mounted on said excentric pinions. excentric with respect to said axes in a direction opposite said pinions.  
 3. A rotary engine comprising a chamber having four lobes,  
 a five-sided rotor in said chamber,  
 diametrically opposite ignition means at two junctions of said lobes,  
 opposite intake ports in the lobes which trail each ignition means in the direction of rotation, said intake ports being remote from said ignition means, opposite exhaust ports in the lobes which lead each ignition means in the direction of rotation, said exhaust ports being remote from said ignition means,  
 a drive shaft on an axis extending centrally of said chamber and gearing connecting said drive shaft to said rotor and including a gear on said rotor,  
 opposite pinions meshing with said rotor gear, said pinions being eceentrically mounted on axes fixed with respect to said chamber, and  
 gearing connecting said pinions to said drive shaft.  
  4. A rotary engine according to claim 3, wherein said rotor gear is an internal gear.  
  5. A rotary engine according to claim 3, wherein said rotor gear has 5 times the number of teeth of one of said excentric pinions.  
  6. A rotary engine according to claim 3, wherein said gearing connecting said pinions to said drive shaft comprises pinions rigid with said eccentric pinions coaxially rotated therewith but concentric with respect to said axes and a gear concentric with and secured to said drive shaft meshing with said concentric pinions.  
  7. A rotary engine according to claim 6 wherein said drive shaft gear is a sun gear.  
  8. A rotary engine according to claim 6 wherein said drive shaft gear is an internal gear.  
  9. A rotary engine according to claim 6 wherein each excentric pinion has the same number of teeth as each concentric pinion.  
  10. A rotary engine according to claim 9, wherein said drive shaft gear has an integral number of times as many teeth as one of said excentric pinions.  
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