Several embodiments of cylinder head and valve train configurations for an overhead valve internal combustion engine that permits increased valve area without interference and while maintaining simplified valve actuation. In each embodiment one pair of valves is operated by one cam shaft and lies on one side of a plane containing the axis of the cylinder. Three other valves are positioned primarily on the other side of the plane and reciprocate about axes that are not parallel with each other. These axes, however, intersect so that each of these three valves may be operated by the same cam shaft. In one embodiment of the invention the intersection of the valves axis is coincident with the axis of rotation of the respective cam shaft so as to permit direct actuation of the valves. In another embodiment the intersection lies substantially along a plane that intersects the stems of the valves when they are closed to facilitate operation of multiple valves from a single cam lobe by means of a single rocker arm.
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15. A valve train for an internal combustion engine comprising a cylinder bore closed by a cylinder head, a cam shaft journaled for rotation relative to said cylinder head, three poppet valves operated by said cam shaft and supported for reciprocation by said cylinder head, at least two of said valves being reciprocal about parallel axes, the third valve reciprocating about an axis that is not parallel to the axis of the first two valves, all of said axes intersect a common axis, said two of said valves having their heads disposed closer to said cylinder bore than said third valve when said valves are in their closed position, said valves all serving the same function.
3. A combustion chamber configuration for an internal combustion engine defined in part by a cylinder head adapted to communicate with a cylinder bore, a pair of valves serving the same function and lying within said cylinder head on one side of a plane containing the axis of the cylinder bore, a pair of valves positioned in said cylinder head and lying substantially on the other side of said plane but having a part thereby lying on said one side of said plane and performing a different function, a third valve positioned within said cylinder head on said other side of said plane and spaced further from said plane of the said other function valves, said third valves also serving said other function.
5. In a valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis comprising an overhead cam shaft, a plurality of poppet valves having head portions and stems and directly operated by said cam shaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axes that are not parallel to each other and each of which is inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the tips of the stems of said valves being disposed radially inwardly toward said cylinder bore axis from an axial extension of said cylinder bore.
7. A valve train wherein for an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis comprising an overhead cam shaft, a plurality of poppet valves having head portions and stems and directy operated by said cam shaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axes that are not parallel to each other and each of which is inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the tips of the stems of said valves being disposed radially inwardly toward said cylinder bore axis from an axial extension of said cylinder bore, said two valves performing the same function.
1. A valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis comprising an overhead cam shaft, a plurality of poppet valves having head portions and stem portions and operated by said cam shaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axes that are not parallel to each other and each of which is inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the tips of the stems of said valves being disposed radially inwardly toward said cylinder bore axis from an axial extension of said cylinder bore, the axis of reciprocation of said valves intersecting at a common line, said common line intersects the axis of rotation of said cam shaft.
10. A valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis comprising an overhead cam shaft, a plurality of poppet valves having head portions and stem portions and operated by said cam shaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axes that are not parallel to each other and each of which is inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the tips of the stems of said valves being disposed radially inwardly toward said cylinder bore axis from an axial extension of said cylinder bore, the axis of reciprocation of said valves intersecting at a common line, said common line of intersection lying substantially along the stems of said valves.
23. A valve train for a an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis
comprising an overhead cam shaft, a plurality of poppet valves having head portions and stem portions and operated by said cam shaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axes that are not parallel to each other and each of which is inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the tips of the stems of said valves being disposed radially inwardly toward said cylinder bore axis from an axial extension of said cylinder bore, the axis of reciprocation of said valves intersecting at a common line, a third valve operated by the cam shaft, communicating with the combustion chamber and reciprocal about an axis parallel to the axis of one of the two first mentioned valves.
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34. A valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis, said valve train comprising an overhead camshaft, a plurality of poppet valves having head portions and stem portions and operated by said camshaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axis that are not parallel to each other and each of which is an inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, said valves being actuated by said camshaft, the axis of rotation of said camshaft being disposed at a lesser distance from said cylinder bore axis than the radius of said cylinder bore, said valves being operated by direct actuation from said camshaft. 35. A valve train for an internal combustion engine as set forth in
intersects the axis rotation of the camshaft. 36. A valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of a cylinder bore having an axis, said valve train comprising an overhead camshaft, a plurality of poppet valves having head portions and stem portions and operated by said camshaft, at least two of said valves communicating with said combustion chamber of the engine, the improvement comprising said two valves being reciprocal about respective axis that are not parallel to each other and each of which is an inclined at an acute angle to said axis of the associated cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves the stems of said valves lying on one side, of said plane, said valves being actuated by said camshaft, the axis of rotation of said camshaft being disposed on said one side of said plane at a lesser distance from said plane than the radius of said cylinder bore. 37. A valve train for an internal combustion engine as set forth in claim 36 wherein the axis of reciprocation of the two valves intersect along a line that extends parallel to the plane containing the cylinder bore axis. 38. A valve train for an internal combustion engine as set forth in claim 36 further including a third valve reciprocal about a respective axis parallel to the axis of reciprocation of one of the other valves. A valve train for an internal combustion engine as set forth in claim 38 wherein the axis of reciprocation of the two valves intersect along a line that extends parallel to the plane containing the cylinder bore axis. 40. A valve train for an internal combustion engine as set forth in claim 39 wherein the valves are operated by direct actuation from the camshaft. 41. A valve train for an internal combustion engine as set forth in claim 40 wherein the line intersects the axis of rotation of the camshaft. 42. A combustion chamber configuration for an internal combustion engine defined in part by a recess in the lower face of a cylinder head adapted to communicate with a cylinder bore, a first pair of valves serving the same function and lying within said cylinder head on one side of a plane containing the axis of said cylinder bore, a second pair of valves positioned in said cylinder head and lying on the other side of said plane and performing a different function, a fifth valve positioned within said cylinder head on said other side of said plane and spaced further from said plane than said second pair of valves, said fifth valve serving the same function as said second pair of valves, the portion of said cylinder defining the seats of said second pair of valves and said fifth valve forming an inclined area and forming with the portion of said cylinder defining the seats for said one function valve a wedge shaped combustion chamber with the intersection of said cylinder head portions lying on said one side of said plane. 43. A combustion chamber configuration for an internal combustion engine as set forth in claim 42 further including a spark plug supported within the cylinder head and disposed away from the intersection of said cylinder head portions and in proximity to the cylinder bore axis. 44. A combustion chamber configuration for an internal combustion engine as set forth in claim 42 wherein the recess formed in the cylinder head lies at least in part within the area defined by the cylinder bore, a squish area is formed between the head of a piston reciprocating in the cylinder bore and a surface of the cylinder head facing the cylinder bore on at least one side of said recess. 45. A combustion chamber configuration for an internal combustion engine as set forth in claim 44 further including a spark plug supported within the cylinder head and disposed away from the intersection of said cylinder head portions and in proximity to the cylinder bore axis. 46. A combustion chamber configuration for an internal combustion engine as set forth in claim 45 wherein the squish area is defined at least in part by a pair of angularly related sections defined outwardly of an area encompassed by a respective one of the second pair of valves and the fifth valve, said angularly related sections being disposed at an angle to each other and at an angle to the plane. 47. A combustion chamber configuration for an internal combustion engine as set forth in claim 46 wherein the squish area is further defined by a portion disposed outwardly from the cylinder bore axis from the first pair of the valves and extends generally parallel to the plane. 48. A combustion chamber configuration for an internal combustion engine as set forth in claim 45 wherein the squish area is defined by an area disposed outwardly of the first pair of valves from the cylinder bore axis and which extends generally parallel to the plane. A valve train for an internal combustion engine as set forth in claim 42 wherein the further including rocker arm means for operating the second pair of valves and the fifth valve from a camshaft. 50. A valve train for an internal combustion engine as set forth in claim 49 wherein the rocker arms means comprises a plurality of rocker arms that are inclined at an obtuse angle to the plane. 51. A valve train for an internal combustion engine as set forth in claim 50 wherein the rocker arms are pivotally supported outwardly of the point where the camshaft engages the rocker arms. 52. A combustion chamber configuration for an internal combustion engine as set forth in claim 42 wherein the second pair of valves reciprocate along axes that are parallel to each other and at an acute angle to the plane, said fifth valve also lying at an acute angle to said plane but at a different acute angle that the acute angle of said second pair of valves. 53. A valve train for an internal combustion engine as set forth in claim 52 wherein the axis of reciprocation of the second pair of valves and the fifth valve intersect along a line that extends parallel to the plane containing the cylinder bore axis. 54. A valve train for an internal combustion engine as set forth in claim 53 wherein the second pair of valves and the fifth valve are operated by direct actuation from a camshaft. 55. A valve train for an internal combustion engine as set forth in claim 54 wherein the line intersects the axis of rotation of the camshaft. 56. A combustion chamber configuration for an internal combustion engine as set forth in claim 52 wherein the first pair of valves reciprocate along a parallel axes that lie at an acute angle to the plane on the other side thereof from the second pair of valves and the fifth valve. 57. A combustion chamber configuration for an internal combustion engine as set forth in claim 56 wherein the acute angle of the first pair of valves is greater than the angle of the axis of reciprocation of the fifth valve and less than the angle of reciprocation of the second pair of valves. 58. A combustion chamber configuration for an internal combustion engine as set forth in claim 56 wherein the acute angle of reciprocation of the first pair of valves is greater than the acute angle of reciprocation of the fifth valve. 59. A combustion chamber configuration for an internal combustion engine as set forth in claim 56 wherein the first pair of valves is operated by a first camshaft disposed on one side of the plane and the second pair of valves and fifth valve is operated by a second camshaft disposed on the other side of said plane, the distance between said second camshaft and said plane being less than the distance between said first camshaft and said plane. 60. A valve train for an internal combustion engine as set forth in claim 59 further including rocker arm means for operating the valves from the respective camshaft. 61. A valve train for an internal combustion engine as set forth in claim 60 wherein the rocker arm means comprises a plurality of rocker arms that are inclined at an obtuse angle to the plane. 62. A valve train for an internal combustion engine as set forth in claim 60 wherein the rocker arms are pivotally supported outwardly of the point where the camshaft engages the rocker arm. 63. A valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of said cylinder bore and having an axis, said valve train comprising a plurality of poppet valves having head portions and stem portions, two of said valves being reciprocal about respective axis that are not parallel to each other and each of which is inclined at an acute angle to said axis of said cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the heads of said two valves being disposed substantially on side of said plane, a second pair of poppet valves having their head portions disposed on the other side of said plane, the stems of said first pair of valves intersecting at a line that is disposed at a distance lesser than the distance from the cylinder bore axis than the radius of the cylinder bore. 64. A valve train for an internal combustion engine as set forth in claim 63 further including a first camshaft supported on one side of said head for operating the first two of said valves and a second camshaft rotatably supported on the other side of said plane for operating said second pair of poppet valves. 65. A valve train for an internal combustion engine as set forth in claim 64 further including a fifth valve performing the same function as the first pair of valves and disposed on said one side of said plane and operated by said first camshaft. 66. A valve train for an internal combustion engine as set forth in claim 65 wherein the axis of reciprocation of the first pair of valves and of the fifth valve intersect along a line that extends parallel to the plane containing the cylinder bore axis. 67. A valve train for an internal combustion engine as set forth in claim 66 wherein the valves are operated by direct actuation from the camshaft. 68. A valve train for an internal combustion engine as set forth in claim 67 wherein the line intersects the axis of rotation of the camshaft. 69. A valve train for an internal combustion engine as set forth in claim 66 further including rocker arm means for operating the first pair of valves from a camshaft. 70. A valve train for an internal combustion engine as set forth in claim 69 wherein the rocker arm means comprises a plurality of rocker arms that are inclined at an obtuse angle to the plane. 71. A valve train for an internal combustion engine as set forth in claim 70 wherein the rocker arms are pivotally supported outwardly of the point where the camshaft engages the rocker arms. 72. A valve train for an internal combustion engine as set forth in claim 66 wherein the line of intersection of the axis of reciprocation of the first pair of valves and the fifth valve is spaced at a distance from the plane less than the radius of the cylinder bore. 73. A valve train for an internal combustion engine as set forth in claim 72 wherein the first pair of valves and the fifth valve comprise intake valves and the second pair of valves comprise exhaust valves. 74. A valve train for an internal combustion engine having a generally concave combustion chamber formed in the lower surface of a cylinder head disposed at one end of a cylinder bore having an axis, said valve train comprising a plurality of poppet valves having head portions and stem portions, at least two of said valves communicating with said combustion chamber of said engine, said two valves being reciprocal about respective axis that are not parallel to each other and each of which is inclined at an acute angle to the axis of the associated cylinder bore and which intersects a plane containing said cylinder axis on the head side of the respective of said valves, an overhead camshaft rotatably supported relative to said cylinder head on the same side of said plane as the heads of said valves, and rocker arm means for operating said two valves from said camshaft, said rocker arm means having a first portion engaged with the tips of said valves and a second portion engaged with said camshaft for pivoting said rocker arms, said second portion being positioned at a point closer to the lower surfaces of said cylinder head than said first portion. 75. A cylinder head construction for an internal combustion engine for closing a cylinder bore, a pair of valves supported for reciprocation within said cylinder head and lying substantially on one side of a plane containing the axis of said cylinder bore, a third valve positioned within said cylinder head on said one side of said plane, said valves all serving the same function, coil spring means encircling the stems of said valves for urging said valves toward their closed position, a generally cylindrical spark plug recess formed in said cylinder head by an upstanding wall disposed in proximity to said cylinder bore axis for receiving a spark plug with its gap extending in the combustion chamber defined by said cylinder head and said cylinder bore, the coil spring means associated with said pair of valves lying on opposite sides of said wall and extending inwardly toward said plane relative to said wall and nesting around said wall, the coil spring means associated with the said third valve lying between the coil spring means of said pair of valves and on the same side of said plane and spaced outwardly from said plane and spaced from said wall so that said spark plug recess and said wall is nested between said coil spring means. 76. A cylinder head construction for an internal combustion engine for closing a cylinder bore and defining a combustion chamber therewith, a first pair of valves serving the same function and lying within said cylinder head on one side of a plane containing the axis of said cylinder bore, a second pair of valves positioned in said cylinder head and lying substantially on the other side of said plane and performing a different function, a fifth valve positioned within said cylinder head on said other side of said plane and serving the same function as said second pair of valves, a first camshaft rotatably journalled on said one side of said plane and having a pair of lobes for operating said first pair of valves, and a second camshaft rotatably journaled relative to said cylinder head on said other side of said plane and having three lobes for operating said other functions valves, said camshafts each being journaled by a pair of spaced apart bearings disposed on the respective side of said plane, outwardly of this respective lobes of said camshafts, said bearings for each of said camshaft being spaced equal distances. 77. A valve train for an internal combustion engine having a generally concave combustion chamber disposed at one end of said cylinder bore and having an axis, said valve train comprising a plurality of poppet valves having head portions and stem portions, two of said valves being reciprocal about respective axis that are not parallel to each other and each of which is included at an acute angle to said axis of said cylinder bore and which intersects a plane containing said cylinder bore axis on the head side of the respective of said valves, the heads of said two valves being disposed substantially on side of said plane, a second pair of poppet valves having their head portions disposed on the other side of said plane, the tips of the stems of said first pair of valves being disposed closer to said plane than the tips of the other of said pair of valves. 78. A valve train for an internal combustion engine as set forth in claim 77 further including a fifth poppet valve reciprocating on the same side of the plane as the first pair of poppet valve and inclined at said plane at an acute angle the same as the angle of one of said first pair of valves, the tip of the stem of said fifth valve being at the same distance from said plane as the tips of said first pair of valves. 79. A valve train for an internal combustion engine as set forth in claim 78 further including a spark plug disposed within the combustion chamber substantially on the axis of the cylinder bore. 80. A valve train for an internal combustion engine comprising a cylinder bore closed by a cylinder head, a camshaft journaled for rotation relative to said cylinder head, three poppet valves operated by said camshaft and supported for reciprocation by said cylinder head, at least two of said valves being reciprocal about parallel axis, the third valve being reciprocal about an axis that is not parallel to the axes of the first two of said valves, said first two of said valves having their heads disposed closer to said cylinder bore than said third valve when said valves are all in their closed position, said valves all serving the same function. 81. A valve train for an internal combustion engine as set forth in claim 80 wherein the three poppet valves are intake valves and further including two poppet type exhaust valves disposed on the opposite side of a plane passing through the cylinder bore and passing through at least two of the intake valves. 82. A valve train for an internal combustion engine as set forth in claim 81 further including a second camshaft journaled for rotation relative to the cylinder head and operating the exhaust valves. 83. A combustion chamber as set forth in claim 4 wherein the intake valves have a smaller head diameter than the exhaust valves. 84. A combustion chamber as set forth in claim 4 wherein the pair of intake valves reciprocate about respective parallel axes that lie at the same acute angle to the plane and the third intake valve reciprocates about an acute angle to the plane different than that of the pair of intake valves. 85. A combustion chamber configured for an internal combustion engine as set forth in claim 84 wherein the axis of reciprocation of the third intake valve is at a lesser acute angle to the plane than the pair of intake valves. 86. A combustion chamber as set forth in claim 4 further including a spark plug contained within the combustion chamber and lying substantially on the axis of the cylinder bore. |
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This invention relates to a four-cycle engine and more particularly to an improved valve and combustion chamber arrangement for such an engine.
As is well known, the performance of a four-cycle engine may be improved through the use of multiple intake and/or exhaust valves. By using multiple valves, the valve area communicating with each chamber may be increased. The use of multiple valves permits an increased valve area without increasing the inertia of individual valve components as would be true if merely larger valves were employed. Hence, higher engine speeds may be attained through the use of multiple valves. In addition, the use of multiple valves permits a greater valve area in a given combustion chamber area. The use of multiple valves, however, does present some difficulties. As a number of valves in a given chamber is increased, it is necessary to place the valves so that they do not interfere with each other during their opening and closing movement. In addition, the use of a greater number of valves may complicate the actuating system for the valves.
It is, therefore, a principal object of this invention to provide an improved and simplified multiple valve arrangement for an internal combustion engine.
It is a further object of the invention to provide a multiple valve arrangement wherein more than one valve is operated by the same cam shaft.
It is desirable to provide a direct valve actuation wherein the cam lobes act directly on the valves to operate them. Such an arrangement reduces the complexity of the valve train and further permits higher speeds due to the lower inertia. However, where multiple valves are employed, and particularly if a greater number of valves than two for either the intake or exhaust are employed, it has been difficult if not impossible to provide such direct action on all valves.
It is, therefore, yet a further object of this invention to provide a combustion chamber for an engine that permits the use of multiple, directly actuated valves.
A first feature of this invention is adapted to be embodied in a valve train for an internal combustion engine that comprises a cam shaft and a plurality of valves operated by the cam shaft, at least two of which communicate with the same chamber of the engine. In accordance with this feature of the invention, the two valve reciprocate about respective axes that are not parallel to each other.
Another feature of the invention is also adapted to be embodied in a valve train for an internal combustion engine. In accordance with this feature of the invention, the valve train includes a cam shaft and at least three valves operated by the cam shaft and which communicate with the same chamber of the engine. In accordance with this feature of the invention, the three valves each reciprocate about a respective axis and the axis of one of the valves is not parallel to the axes of the remaining valves.
Yet another feature of this invention is adapted to be embodied in a combustion chamber for a reciprocating engine. In accordance with this feature of the invention, a cylinder head forms a closure for a cylinder bore and defines at least in part the engine combustion chamber. The cylinder head is configured with at least two valves of the same function that lie on one side of a plane containing the axis of the cylinder bore. At least three valves of a different function also lie within the combustion chamber. One of these three valves is positioned further from the plane than the other two valves and these three valves lie predominantly on the other side of the enginethelesser greater inclination of the intake valves 19 to the center plane 18, the charge flowing through the intake passages 16 will impinge on the opposing portion of the cylinder wall 13 and be directed generally toward the center of the wall. The charge from the intake passage 17 will not impinge upon the cylinder wall as soon and, hence, this charge will be directed more toward the center of the cylinder bore 13. As the piston C moves upwardly, the flow from the intake passages 16, as indicated by the arrows S2 and S2 will impinge on the head of the piston and be redirected to flow in a generally circumferential direction to improve charge distribution within the combustion chamber 15.
In the illustrated embodiments there are three intake valves and only two exhaust valves. It is believed to be readily apparent to those skilled in the art that an arrangement may be employed with the exhaust valves similar to that employed with the intake valves so that three exhaust valves may also be utilized. Furthermore, more than three valves of each function may also be used in conjunction with the engine. Various other changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims.
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