Reed valve with multiple ports

Abstract

A reed valve seat with multiple ports allows a reed valve to operate under extreme pressures in a variable cam timing system. A check valve includes a valve seat in a variable cam timing phaser with a contact surface and multiple ports for fluid in control passages within the phaser to flow through. A reed creates a seal with the contact surface of the valve seat when the reed contacts the valve seat such that reverse flow of fluid in the variable cam timing phaser is prevented.

1 . A check valve comprising: 
 a) a valve seat in a variable cam timing phaser comprising a contact surface and having a plurality of ports for fluid in control passages within the phaser to flow through; and    b) a reed that creates a seal with the contact surface of the valve seat when the reed contacts the valve seat;    such that reverse flow of fluid in the variable cam timing phaser is prevented.    
   
   
       2 . A variable cam timing phaser comprising: 
 a) a housing having an outer circumference for accepting drive force;    b) a rotor for connection to a camshaft coaxially located within the housing, the housing and the rotor defining at least one vane separating a plurality of chambers, at least one chamber being an advance chamber and another chamber being a retard chamber, the vane being capable of rotation to shift the relative angular position of the housing and the rotor;    c) a spool valve comprising a spool having a plurality of lands slidably mounted within a bore in the rotor, the spool slidable from an advance position through a null position to a retard position;    d) a plurality of control passages in the housing and the rotor for selectively permitting fluid flow from the spool valve to the advance chamber and the retard chamber, wherein the lands of the spool block and connect the control passages such that by slidably moving the spool, the flow of fluid from a fluid input to the advance chamber and the retard chamber is controlled, varying the rotational movement of the housing relative to the rotor; and    e) at least one check valve comprising a valve seat comprising a contact surface and having a plurality of ports for fluid in the control passages to flow through, and a reed that creates a seal with the contact surface of the valve seat when the reed contacts the valve seat, such that reverse flow of fluid through the check valve is prevented.    
   
   
       3 . The variable cam timing phaser of  claim 2 , 
 wherein the spool comprises length and a first land and a second land, spaced apart a distance along the length, such that the first land and the second land have a circumference which provides a fluid blocking fit in a cylindrical recess of the rotor, and the length has a lesser circumference than the first land and the second land to permit fluid to flow; and    the cylindrical recess of the rotor comprising, in spaced-apart relationship along a length of the cylindrical recess from a first end of the cylindrical recess most distant from the camshaft to a second end of the cylindrical recess closest to the camshaft:    a first exhaust vent connecting the cylindrical recess to atmosphere;    a first return passage connecting the advance chamber to the cylindrical recess;    a first movement passage connecting the cylindrical recess to the advance chamber;    a central inlet passage connecting a central location in the cylindrical recess to a source of fluid;    a second movement passage connecting the cylindrical recess to the retard chamber;    a second return passage connecting the retard chamber to the cylindrical recess;    a second exhaust vent connecting the cylindrical recess to atmosphere;    the first exhaust vent, second exhaust vent, first return passage, second return passage, first movement passage, second movement passage and central inlet passage being spaced apart along the length of the cylindrical recess, and the first land and the second land being of sufficient length and distance apart such that;    when the spool is in a central position between the first end of the central recess and the second end of the central recess, the first land blocks the first return passage and the first movement passage, and the second land blocks the second movement passage and the second return passage;    when the spool is in a position nearer the first end of the central recess, the first movement passage and second return passage are unblocked, fluid from the central inlet passage flows into the first movement passage and the advance chamber, and fluid from the retard chamber flows into the second return passage and the second exhaust vent; and    when the spool is in a position nearer the second and of the central recess, the second movement passage and first return passage are unblocked, fluid from the central inlet passage flows into the second movement passage and the retard chamber, and fluid from the advance chamber flows into the first return passage and the first exhaust vent.    
   
   
       4 . The variable cam timing phaser of  claim 2 , wherein the check valve comprises a first check valve and a second check valve; 
 wherein the rotor further comprises a central cylindrical recess located along an axis of rotation;    wherein the central cylindrical recess of the rotor comprises: 
 a first movement passage connecting the cylindrical recess to the advance chamber, wherein the first check valve is located within the first movement passage, such that the first check valve is positioned to permit flow of fluid into the advance chamber;  
 a second movement passage connecting the cylindrical recess to the retard chamber, wherein the second check valve located within the second movement passage, such that the second check valve is positioned to permit flow of fluid into the retard chamber.  
   
   
   
       5 . The variable cam timing phaser of  claim 2;  wherein the check valve comprises a first check valve and a second check valve in the plurality of control passages connecting the advance chamber and the retard chamber, wherein the plurality of control passages recirculate fluid to and from the spool valve to the advance chamber and the retard chamber.  
   
   
       6 . The variable cam timing phaser of  claim 2 , wherein the variable cam timing phaser is selected from the group consisting of a cam torque actuated phaser and a torsion-assist phaser.  
   
   
       7 . A check valve comprising: 
 a) a valve seat in a rotary actuator comprising a contact surface and having a plurality of ports for fluid in control passages within the rotary actuator to flow through; and    b) a reed that creates a seal with the contact surface of the valve seat when the reed contacts the valve seat;    such that reverse flow of fluid in the rotary actuator is prevented.    
   
   
       8 . A rotary actuator comprising at least one camshaft comprising: 
 a fixed part with motion restricted to less than 360°, and a rotating part for accepting drive force and connection to a shaft coaxially located within the fixed part, the fixed part and the rotating part defining at least one vane separating a chamber in the fixed part into a clockwise chamber and a counterclockwise chamber, the vane being capable of rotation to shift the relative angular position of the fixed part and the rotating part; and    a check valve comprising a valve seat comprising a contact surface and having a plurality of ports for fluid in control passages within the rotary actuator to flow through, and a reed that creates a seal with the contact surface of the valve seat when the reed contacts the Valve seat, such that reverse flow of fluid in the rotary actuator is prevented.    
   
   
       9 . A check valve comprising: 
 a) a valve seat in a linear actuator comprising a contact surface and having a plurality of ports for fluid in control passages within the linear actuator to flow through; and    b) a reed that creates a seal with the contact surface of the valve seat when the reed contacts the valve seat;    such that reverse flow of fluid in the linear actuator is prevented.    
   
   
       10 . A linear actuator, comprising: 
 a housing;    a piston that moves within the housing in response to fluid pressure; and    a check valve comprising a valve seat comprising a contact surface and having a plurality of ports for fluid in control passages within the linear actuator to flow through, and a reed that creates a seal with the contact surface of the valve seat when the reed contacts the valve seat, such that reverse flow of fluid in the linear actuator is prevented.