US 3828741 A
An internal combustion engine in which the usual crankshaft is replaced by a grooved drum connected to the pistons by rigid links passing through a slot into the lateral wall of each cylinder and into which engine the cylinders are closed at both ends and form a combustion chamber at each end of each piston. The rigid links couple the pistons in pairs to prevent rotation of the pistons on themselves while producing rotation of the grooved drum by converting the rectilinear movement of the pistons into rotary movement of the drive shaft of the engine.
Claims available in
Description (OCR text may contain errors)
mitten states eaten [191 Bixier 1 KNTERNAL CQMBUSTHON ENGllNE  Inventor: Antonio Bixier, 266 Geoffroy St.,
Pont Viau, Laval, Province of Quebec, Canada  Filed: Jan. 11, 1973  Appl. No.: 322,826
 Foreign Application Priority Data Jan. 13, 1972 Canada 132392 [52} US. Cl 123/58 AB, 123/61 R, 123/62, 123/58 R  int. Cl. F021) 75/26  Field of Search 123/61 R, 62, 58 AB, 58 R, 123/58 A, 58 BB, 58 BA l 56] References (Iited UNlTED STATES PATENTS 1,007,331 10/1911 Brown 1,643,584 9/1927 Picketts 123/62 1,762,437 6/1930 Franklin 123/58 AB 1,802,902 4/1931 Brau l t v. 123/58 AB 3,745,981 7/1973 Warner 123/58 AB Aug. 13, 1974 Primary Examiner-Wendell E. Burns Attorney, Agent, or FirmPierre Lesperance 5 7 ABSTRAT An internal combustion engine in which the usual crankshaft is replaced by a grooved drum connected to the pistons by rigid links passing through a slot into the lateral wall of each cylinder and into which engine the cylinders are closed at both ends and form a combustion chamber at each end of each piston. The rigid links couple the pistons in pairs to prevent rotation of the pistons on themselves while producing rotation of the grooved drum by converting the rectilinear movement of the pistons into rotary movement of the drive shaft of the engine.
A preferred embodiment defines a two-stroke engine having a novel intake system formed by each piston including an internal cavity, an intake member transversely projecting into the internal cavity of each piston dividing the same into two intake chambers, and with check valves and channels associated with each intake chamber.
3 Claims, 7 Drawing Figures INTERNAL COMBUSTION ENGINE This invention relates to internal combustion engines.
The internal combustion engines which are now in common use comprise cylinders which are closed at one end only and a piston into each cylinder defining a combustion chamber at one end only of the latter. A piston rod connects the other end of each piston to a crankshaft to convert the rectilinear movement of the pistons into a rotary movement of a drive shaft. There results from such arrangement that each. group of a piston and cylinder is inefficiently used, since only one end of the piston operates to produce work, the other end of the same piston merely constituting a dead weight. Furthermore, the usual crankshaft constitutes a complex element of relatively expensive construction.
It has beenknown to replace the crankshaft by a grooved cylindrical cam secured to the drive shaft, but this was done by using conventional groups of piston and cylinder parallel to the cam and by connecting the piston rods to the cylindrical cam to rotate the latter. Such arrangement is unsatisfactory since the piston rods must then be positively supported and thus, there is produced a supporting mechanism for the latter which nullifies the simplicity otherwise obtained by avoiding the crankshaft.
It is a general object of the invention to eliminate the conventional crankshaft from internal combustion engines and to provide a simple connecting assembly between the pistons and the drive shaft to preserve the advantages obtained by the above-mentiond elimination.
It is another general object of the invention to provide an engine which includes groups of piston and cylinder having a combustion chamber at each of the opposite ends of each cylinder, such as to produce an engine, the weight to power ratio of which is relatively low and consequently which is more efficient.
It is another object of the invention to provide a twocycle internal combustion engine which is of simple construction.
The invention will now be described in detail with reference to preferred embodiments thereof, which are illustrated, by way of example only, in the accompanying drawings, wherein:
FIG. 1 is a cross-sectional and diagrammatic view of an engine according to the present invention;
FIG. 2 is a longitudinal cross-section of a cylinder and piston as seen along line 2-2 in FIG. 1;
FIG. 3 is a side view of a drive shaft assembly forming part of the present invention;
FIGS. 4 and 5 are detail views of different pairs of ball bearings engaging into the groove of the cam forming drum; and
FIGS. 6 and 7 are longitudinal cross-sectional views of a cylinder and piston for a two-cycle engine, shown into different positions respectively.
The illustrated engine includes a drive shaft 1 fixedly retained by bearings 2 or other suitable elements. A gear 3, of any appropriate type, is secured to the shaft 1 and transmits rotation thereto in any appropriate manner. A flywheel 4 is mounted onto the shaft 1 to regulate the rotation of the latter.
A cam 5 having the shape of a cylindrical solid body, or drum, is secured to thedrive shaft 1 for rotation therewith. The cam 5 has a generally ellipsoidal groove 6 running around the circumference thereof between longitudinally and diametrically spaced extreme points defining the stroke of the pistons which are hereinafter described.
According to one embodiment of the invention, the engine includes four cylinders A, B, C, and D, as shown in FIG. 1. Each cylinder A, B, C or D is closed at both ends, as illustrated in FIG. 2, such as to form a combustion chamber at each end ofa piston 7 movable into the corresponding cylinder. Each end of each cylinder A. B, C, and D is provided with a spark plug 8, an intake valve 9 and an exhaust valve 10 of any well known construction.
Each cylinder is formed with a longitudinal slot 11 through its lateral wall. Rigid links or connectors 12 are secured to the pistons 7 respectively, pass through the lateral wall of the cylinders through the slots ill and are joined in pairs to form a projection 13. A pair of ball bearings 14 are rotatably mounted on the free end of each projection 13 and engage with the opposite parallel faces of the groove 6 respectively, such that for each projection a ball bearing engages one face and the other ball bearing engages the other opposite face. This may be achieved either by offsetting the axes of the ball bearing, as shown in FIG. 4, or by forming shoulders into each of the two opposite faces, as shown in FIG. 5.
It should be noted that both bearings transmit the driving force of the pistons to the cam or drum 5 by acting on one or the other of the two opposite faces through one or the other of the two ball bearings 14 which thus rotate in opposite directions and avoid substantial friction with the cam.
The heretofore described engine is a four-cycle engine which is arranged such that the two projections 13 engage into the groove 6 at diametrically opposite points, such that when a projection 13 is at one of the two extreme points of the stroke. the other projection 13 is at the other extreme point. Thus, the engine is built such that the two pistons on one side, which are connected to the same projection 13, travel together and the other two pistons also travel together. The engine is also synchronized such that there is a two-stroke delay between the cylinders A and B as well as between the cylinders C and D. There results that when there is an explosion at one end of the cylinder A, there is intake at the corresponding end of the cylinder B. During that operation, at the other end of A there is exhaust and at the other end of B, there is compression of the air fuel mixture. The same happens between C and D but, obviously, with an appropriate phase shift.
FIGS. 6 and 7 show a two-stroke engine, also having cylinders forming two combustion chambers at the opposite ends respectively of a single piston.
The group of a piston and cylinder of FIGS. 6 and 7 comprises a cylinder 15 closed at both ends and having a pair of exhaust ports 16, one for each combustion chamber, and a longitudinal slot 11 for the possage of a rigid link 12 for connection to the cam 5. A spark plug 17 is provided at each end of the cylinder 15. A hollow member 18 forms a passage for the intake of the air fuel mixture, enters into the cylinder 15 and effectively divides the latter at its center. The hollow intake member 18 includes check valves 19 and 20 on its opposite sides respectively.
A piston 21 is housed into the cylinder and defines the two combustion chambers at its opposite ends. The piston 21 is hollow forming a pair of intake chambers for the air fuel mixture on opposite sides respectively of the intake member 18. A passage 22 is provided on each side of the intake member 18 and is adapted to allow the passage of the air fuel mixture from each intake chamber into the corresponding combustion chamber.
As seen in FIG. 6, the intake chamber on the left is filled with a quantity of uncompressed mixture and the combustion chamber is filled with the compressed mixture. On the right, the exhaust of the burnt gases is produced through the corresponding exhaust port 16, assisted by scavenging produced by the mixture which had previously been compressed into the intake chamber on the right by the preceding stroke of the piston 21. The mixture which was thus compressed fills the combustion chamber on the right passing through the passage 22 on the same side. After explosion into the combustion chamber on the left, the piston 21 displaces towards the right closing the passage 22. This allows the intake of the mixture into the intake chamber on the right and the compression of the mixture into the combustion chamber on the right. During that operation, the mixture previously admitted into the intake chamber on the left becomes more and more compressed until the position of FIG. 7 is reached. This corresponds to the position of FIG. 6 but reversed from left to right. Consequently, the explosion in the combustion chamber on the right will produce the opposite movement by closing of the valve and opening of the valve 19.
1. An internal combustion engine comprising a drive shaft, cylinders fixedly mounted around and parallel to said shaft, a piston mounted into each of said cylinders, the latter and the corresponding pistons being constructed and arranged to form a combustion chamber at each end of each of said pistons. a cylindrical cam coaxially and rigidly secured to said drive shaft and having a groove of generally ellipsoidal shape extending around the circumference thereof between points of the latter which are longitudinally and diametrically spaced apart from each other, each of said cylinders having a longitudinal slot through the wall thereof, rigid links projecting through said slots and rigidly interconnecting together two transversely adjacent pistons of transversely adjacent and distinct cylinders respectively, and each of said rigid links including a projection extending transversely of said cylindrical cam intermediate the two corresponding adjacent cylinders and operatively engaging the lateral walls of said ellipsoidal groove for rotational action thereon upon bodily longitudinal displacement of the corresponding two pistons.
2. An internal combustion engine as defined in claim 1, wherein said lateral walls of said grooves are parallel one to the other and a pair of ball bearings are mounted on each of said projections and are arranged to roll onto said lateral walls respectively.
3. An internal combustion engine as defined in claim 2, wherein each of said pistons includes an internal cavity, an intake member for the fuel mixture projects through the lateral wall of each of said cylinders and into the corresponding internal cavity and is constructed and arranged to divide the latter into two intake chambers for said mixture, 21 pair of check valves are fixed to each of said intake members in communication with said intake chambers respectively, and channels connect said intake chambers to said combustion chambers respectively and are arranged to allow the flow of the fuel mixture from the intake chambers to the combustion chambers.