Internal combustion engine

Abstract

An internal combustion engine has a cylinder block that defines a blind cylinder bore that terminates within the cylinder block. A piston is positioned within the blind cylinder bore. The piston is connected to two crankshafts. A combustion chamber is formed between the piston and the blind end of the cylinder bore. Various mechanisms can provide actuation, timing control, and during control of valves that control flow into and out of the combustion chamber.

1 - 20 . (canceled) 
     
     
         21 . An assembly for an internal combustion engine comprising:
 a cam shaft configured to rotate about a first axis;   an auxiliary shaft configured to rotate about a second axis;   a primary gear configured to rotate with the cam shaft about the first axis;   a first auxiliary gear configured to rotate with the auxiliary shaft about the second axis, the primary gear in mesh with the first auxiliary gear such that the cam shaft drives rotation of the auxiliary shaft; and   one or more cam lobes positioned on the cam shaft, the one or more cam lobes controlling movement of at least one valve of the internal combustion engine.   
     
     
         22 . The assembly of  claim 21 , wherein the one or more cam lobes comprise:
 one or more first cam lobes positioned on the cam shaft and configured to rotate with the cam shaft about the first axis; and   one or more second cam lobes positioned on the cam shaft and configured to rotate independently of the cam shaft, wherein rotation of the one or more second cam lobes is controlled by rotation of the auxiliary shaft.   
     
     
         23 . The assembly of  claim 22 , further comprising one or more second auxiliary gears configured to rotate with the auxiliary shaft about the second axis, wherein each of the one or more second cam lobes is coupled to or integrally formed with a cam gear, and wherein each cam gear is in mesh with one of the one or more second auxiliary gears. 
     
     
         24 . The assembly of  claim 22 , wherein each of the one or more first cam lobes controls movement of at least one intake valve and at least one exhaust valve of the internal combustion engine, and wherein each of the one or more second cam lobes controls movement of at least one intake valve and at least one exhaust valve of the internal combustion engine. 
     
     
         25 . The assembly of  claim 22 , wherein noses of the one or more first cam lobes are angularly offset relative to noses of the one or more second cam lobes about the first axis. 
     
     
         26 . The assembly of  claim 22 , wherein a ratio of first cam lobes to second cam lobes is 1:2. 
     
     
         27 . The assembly of  claim 22 , wherein each of the one or more first cam lobes are coupled to the cam shaft using a collet. 
     
     
         28 . The assembly of  claim 27 , wherein the collet has an inner surface with a fixed diameter and a taper outer surface with a variable diameter along a length of the collet. 
     
     
         29 . The assembly of  claim 27 , wherein the collet comprises a plurality of collet wedges that are at least partially separable from each other. 
     
     
         30 . The assembly of  claim 29 , wherein each collet wedge of the plurality of collet wedges has a trapezoidal cross section. 
     
     
         31 . The assembly of  claim 21 , wherein the primary gear is coupled to or integrally formed with the cam shaft. 
     
     
         32 . The assembly of  claim 21 , furthering comprising a differential assembly configured to adjust an angular position of the cam shaft relative to a crankshaft of the internal combustion engine such that timing of at least one of opening or closing of one or more of the at least one valve can be adjusted. 
     
     
         33 . The assembly of  claim 21 , wherein the auxiliary shaft includes one or more recessed portions along its length, the one or more recessed portions being aligned with the one or more cam lobes such that the auxiliary shaft and cam shaft can be in close proximity to each other without interference between the one or more cam lobes and the auxiliary shaft. 
     
     
         34 . The assembly of  claim 21 , wherein the cam shaft includes an oil passage extending along at least a portion of a length of the cam shaft. 
     
     
         35 . The assembly of  claim 34 , wherein the oil passage comprises a primary oil passage aligned with the first axis and one or more secondary oil passages connected to and extending at an angle from the primary oil passage. 
     
     
         36 . The assembly of  claim 21 , wherein an outer surface of the cam shaft includes one or more mounting portions having a greater roughness relative to a majority of the outer surface of the cam shaft. 
     
     
         37 . The assembly of  claim 21 , wherein at least one of the one or more cam lobes is configured to move a pushrod, and wherein the pushrod acts against one or more rocker arms to cause movement of the at least one valve. 
     
     
         38 . The assembly of  claim 21 , wherein at least one of the one or more cam lobes is configured to cause movement of a valve actuating arm comprising a paw, the paw positioned within a paw slot, the paw and the paw slot cooperating to restrain movement of the valve actuating arm. 
     
     
         39 . The assembly of  claim 21 , wherein at least one of the one or more cam lobes is configured to contact a cam follower mounted to a rocker arm, and wherein positioning of the rocker arm is controlled by a lash adjuster. 
     
     
         40 . An assembly for an internal combustion engine comprising:
 a first shaft configured to rotate about a first axis;   a second shaft configured to rotate about a second axis, wherein rotation of the second shaft is driven by rotation of the first shaft; and   a plurality of lobes positioned on the first shaft, wherein rotation of the first shaft causes corresponding rotation of at least one lobe of the plurality of lobes, and wherein rotation of the second shaft causes corresponding rotation of at least one lobe of the plurality of lobes.