Rolling locking assembly for camshaft phaser

Abstract

A camshaft phaser is provided that includes a stator and a rotor having a locking assembly. The locking assembly has a first unlocked position and a second locked position and is configured to roll against the stator in the first unlocked position and lock the rotor to the stator in the second locked position. The locking assembly can include a locking pin, a retention insert, and a rolling element arranged within the retention insert.

1 . A camshaft phaser, comprising:
 a stator;   a rotor having:   a plurality of vanes that form fluid chambers with the stator; and
 a locking assembly having:
 a retention insert disposed within an aperture, the retention insert movable in a longitudinal direction of the aperture and configured to receive a rolling element; 
 a locking pin disposed at least, partially within the aperture; and 
 a bias spring arranged between, the retention insert and locking pin; and 
 
 in a first unlocked position of the locking assembly, the retention insert is pushed against the stator via a first force and rolls on the stator via the rolling element; and
 in a second locked position of the locking assembly, the retention insert is pushed against the stator via a second force different than the first force. 
 
   
     
     
         2 . The camshaft phaser of  claim 1 , wherein the locking assembly is configured to roll against a flat axial surface of the stator. 
     
     
         3 . The camshaft phaser of  claim 1 , further comprising a cover that is non-rotatably attached to the stator, the locking assembly configured to roll against the cover. 
     
     
         4 . (canceled) 
     
     
         5 . The camshaft phaser of  claim 1 , wherein the rolling element is a ball or a roller. 
     
     
         6 . The camshaft phaser of  claim 1 , wherein the locking pin is configured to be hydraulically actuated via a groove extending directly from a locking end of the aperture, the groove arranged on an axial face of the rotor. 
     
     
         7 . (canceled) 
     
     
         8 . (canceled) 
     
     
         9 . The camshaft phaser of  claim 1 , wherein the locking pin protrudes from a locking end of the aperture to engage the stator. 
     
     
         10 . The camshaft phaser of  claim 9 , wherein the retention insert includes at least one outlet configured to provide an exit pathway for at least one of hydraulic fluid or air from the aperture. 
     
     
         11 . The camshaft phaser of  claim 10 , wherein an axial face of the rotor is configured with a vent passage extending directly from an end of the aperture. 
     
     
         12 . The camshaft phaser of  claim 11 , wherein the vent passage is transverse to a central axis of the aperture and extends radially inwardly from the end of the aperture. 
     
     
         13 . The camshaft phaser of  claim 1 , wherein the aperture is located within one of the plurality of vanes. 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . A method for operating a camshaft phaser, comprising:
 providing the camshaft phaser that includes:
 a stator; 
 a rotor having a plurality of vanes that form fluid chambers with the stator; and, 
 a locking assembly configured to selectively lock the rotor to the stator or selectively unlock the rotor from the stator, the locking assembly having:
 a retention insert disposed within an aperture the retention insert movable in a longitudinal direction of the aperture and configured to receive a rolling element; 
 a locking pin disposed at least partially within the aperture; and 
 a bias spring arranged between the retention insert and locking pin; and 
 
   actuating the locking assembly to unlock the rotor from the stator, defining a first unlocked position in which the retention insert is pushed against the stator via a first force; and   rotating the rotor relative to the stator, causing the rolling element to roll against the stator; and,   actuating the locking assembly to lock the rotor to the stator to prevent rotation of the rotor relative to the stator, defining a second locked position in which the retention insert is pushed via against the stator via a second force different than the first force.   
     
     
         17 . The method of  claim 16 , wherein the rotor further comprises:
 a first axial face of the rotor defining a first groove; and,   a second axial face of the rotor defining a second groove; and,   the first groove extending from a first end of the aperture, and the second groove extending from a second end of the aperture, the first groove configured to deliver pressurized hydraulic fluid to a locking pin, and the second groove configured as a vent passage for the aperture.   
     
     
         18 . The method of  claim 16 , wherein the actuating the locking assembly to unlock the rotor from the stator step and the rotating the rotor step are accomplished by hydraulic fluid pressure acting on the locking assembly and rotor, respectively. 
     
     
         19 . (canceled) 
     
     
         20 . The method of  claim 16 , wherein the actuating the locking assembly to lock the rotor to the stator step is accomplished by the bias spring arranged within the locking assembly, the bias spring providing a force that is greater than a hydraulic fluid force acting on the locking assembly in the second locked position. 
     
     
         21 . A camshaft phaser, comprising:
 a stator;   a rotor having:
 a plurality of vanes that form fluid chambers with the stator; and 
 a locking assembly having:
 a retention insert disposed within an aperture and configured to receive a rolling element; and: i) in an initial assembly state of the camshaft phaser, the retention insert is fixed to the aperture; and ii) after the initial assembly state of the camshaft phaser, the retention insert is movable within the aperture; and 
 a locking pin disposed at least partially within the aperture; and 
 a bias spring arranged between the retention insert and locking pin; and 
 after the initial installation state: 
 in a first unlocked position of the locking assembly, the retention insert is pushed against the stator via a first force and rolls on the stator via the rolling element; and 
 in a second locked position of the locking assembly, the retention insert is pushed against the stator via a second force different than the first force. 
 
   
     
     
         22 . The camshaft phaser of  claim 21 , wherein the second force is less than the first force. 
     
     
         23 . The method of  claim 16 , wherein the second force is less than the first force.