Valve actuator assembly

Abstract

A valve actuator assembly includes an axially moveable valve and a ramp roller thrust drive. The ramp roller thrust drive includes at least first and second opposed thrust plates, each plate including one or more ramps. A roller is positioned between corresponding opposed plate ramps and a rotation of one of the thrust plates relative to the other thrust plate causes the plates to move axially relative to one another such that axial motion is imparted to the valve.

1 . A valve actuator assembly comprising: 
 an axially movable valve; and    a ramp roller thrust drive including at least first and second opposed thrust plates, each plate including one or more ramps, and further including at least one roller positioned between corresponding opposed plate ramps, wherein a rotation of one of the thrust plates relative to the other thrust plate causes the plates to move axially relative to one another such that axial motion is imparted to the valve.    
   
   
       2 . The valve actuator assembly of  claim 1 , wherein the valve is in an internal combustion engine.  
   
   
       3 . The valve actuator assembly of  claim 1 , wherein the ramp roller thrust drive is a double roller thrust drive including a third stacked thrust plate.  
   
   
       4 . The valve actuator assembly of  claim 3 , wherein the center thrust plate is caused to rotate and the other two of the thrust plates are prevented from rotating.  
   
   
       5 . The valve actuator assembly of  claim 4 , wherein at least one of the stationary thrust plates is prevented from rotating using a slotted clip and a pin.  
   
   
       6 . The valve actuator assembly of  claim 1 , further including a lash adjuster for biasing the valve in a closed position.  
   
   
       7 . The valve actuator assembly of  claim 1 , further including a spring for biasing the valve in a closed position.  
   
   
       8 . The valve actuator assembly of  claim 7 , further including a valve keeper for coupling the spring to the valve.  
   
   
       9 . The valve actuator assembly of  claim 7 , wherein one of the thrust plates provides a seat for the spring.  
   
   
       10 . The valve actuator assembly of  claim 1 , wherein a valve stem of the valve extends axially through at least one thrust plate and keeps the plates in a proper relationship to one another.  
   
   
       11 . The valve actuator assembly of  claim 1 , further including at least one snap ring for coupling a movable plate to a valve stem of the valve.  
   
   
       12 . The valve actuator assembly of  claim 1 , further including a plate actuating mechanism configured to rotate one of the thrust plates relative to the other thrust plate.  
   
   
       13 . The valve actuator assembly of  claim 12 , wherein the plate actuating mechanism includes one of an electromagnetic actuator and an electromechanical actuator.  
   
   
       14 . The valve actuator assembly of  claim 12 , wherein the plate actuating mechanism is configured to provide oscillating motion to one of the thrust plates.  
   
   
       15 . The valve actuator assembly of  claim 12 , wherein the plate actuating mechanism includes a crankshaft and a connecting rod.  
   
   
       16 . The valve actuator assembly of  claim 1 , further including a coupling mechanism linking the ramp thrust drive and the valve, wherein the coupling mechanism multiplies an amount of axial movement of the ramp thrust drive which is imparted to the valve.  
   
   
       17 . The valve actuator assembly of  claim 16 , wherein the coupling mechanism includes one of a finger follower and a pivot rocker arm.  
   
   
       18 . The valve actuator assembly of  claim 1 , wherein the roller and the ramps include gear teeth.  
   
   
       19 . A valve actuator assembly comprising: 
 a valve axially movable between a closed position for preventing a flow of gas to or from a combustion chamber of an internal combustion engine and an open position for allowing a flow of gas to or from the combustion chamber;    a ramp roller thrust drive including at least first and second opposed thrust plates, each plate including one or more ramps and including a corresponding roller positioned between opposed plate ramps such that rotation of one of the thrust plates relative to the other thrust plate causes the plates to move axially relative to one another such that axial motion is imparted to the valve; and    a plate actuating mechanism configured to provide oscillating rotative motion to one of the thrust plates relative to the other thrust plate.    
   
   
       20 . A method for actuating an axially movable valve, the method comprising: 
 providing a ramp roller thrust drive including at least first and second opposed thrust plates, each plate including one or more ramps, and further including at least one roller positioned between corresponding opposed plate ramps; and    rotating one of the thrust plates relative to the other thrust plate to impart axial motion to the valve.