Development of a switching roller finger follower for cylinder deactivation in internal combustion engines

Abstract

A switching rocker arm for engaging a cam includes a first arm having a first end and a second end, and a first and a second side arm; a second arm disposed between the first and second side arms, having a first end and a second end, where the second arm is an inner arm. The second arm is pivotably secured adjacent its first end to the first arm adjacent the first end of the first arm. The rocker arm includes an over-travel limiter that limits pivoting motion of the first arm relative to the second arm, where the over-travel limiter is pivotally coupled to the outer arm and interacts with the inner arm.

What is claimed is: 
     
         1 . A switching rocker arm for engaging a cam, comprising:
 a first arm having a first end, a second end, a first and a second side arm, wherein the first arm is an outer arm;   a second arm disposed between the first and second side arms, having a first end and a second end, wherein the second arm is an inner arm;   wherein the second arm is pivotably secured adjacent its first end to the first arm adjacent the first end of the first arm; and   an over-travel limiter that limits pivoting motion of the first arm relative to the second arm, wherein the over-travel limiter is pivotally coupled to the outer arm and interacts with the inner arm.   
     
     
         2 . The switching rocker arm of  claim 1 , wherein the over-travel limiter comprises a portion of the first end of the first arm. 
     
     
         3 . The switching rocker arm of  claim 1 , further comprising a latch that selectively pivotally couples the inner arm to the outer arm. 
     
     
         4 . The switching rocker arm of  claim 3 , wherein the latch pivotally couples the inner arm to the outer arm at the second end of each of the inner arm and the outer arm. 
     
     
         5 . The switching rocker arm of  claim 1 , wherein the latch comprises a circular cross-section. 
     
     
         6 . The switching rocker arm of  claim 5 , wherein at least one of the first arm and the second arm comprises an arcuate latch seat, wherein the latch in an extended position engages the arcuate latch seat to operatively engage the second arm with the first arm. 
     
     
         7 . The switching rocker arm of  claim 4 , further comprising a hydraulic lash adjuster that engages one of the inner arm and the outer arm, and wherein the hydraulic lash adjuster is a dual feed hydraulic lash adjuster. 
     
     
         8 . The switching rocker arm of  claim 5 , wherein the hydraulic lash adjuster comprises an oil passage fluidly coupled to the latch, and wherein the latch selectively pivotally couples the inner arm to the outer arm in response to one of supplied oil pressure and released oil pressure. 
     
     
         9 . The switching rocker arm of  claim 7 , wherein the latch is disposed adjacent a first end of the rocker arm, and where the hydraulic lash adjuster is fluidly coupled to the rocker arm at a position adjacent the first end of the rocker arm. 
     
     
         10 . The switching rocker arm of  claim 9 , wherein the first end of the rocker arm is adjacent the first end of the first arm. 
     
     
         11 . The switching rocker arm of  claim 9 , wherein the first end of the rocker arm is adjacent the second end of the first arm. 
     
     
         12 . The switching rocker arm of  claim 1 , wherein the first arm comprises a cam-contacting member to engage the first cam, and wherein the cam-contacting member comprises a slider pad. 
     
     
         13 . The system of  claim 12 , further comprising at least one biasing spring disposed between the first arm and the second arm, the at least one biasing spring biasingly coupled to the cam-contacting member. 
     
     
         14 . A switching rocker arm for engaging a cam, comprising:
 a rocker arm assembly for operative engagement with the cam, the rocker arm assembly comprising:   a first arm having a first end, a second end, a first and a second side arm, wherein the first arm is an outer arm;   a second arm disposed between the first and second side arms, having a first end and a second end, wherein the second arm is an inner arm;   wherein the second arm is pivotably secured adjacent its first end to the first arm adjacent the first end of the first arm;   an over-travel limiter that limits pivoting motion of the first arm relative to the second arm, wherein the over-travel limiter is pivotally coupled to the outer arm and interacts with the inner arm, and wherein the over-travel limiter comprises a portion of the first end of the first arm; and   a latch that selectively pivotally couples the inner arm to the outer arm.   
     
     
         15 . The switching rocker arm of  claim 14 , wherein the latch comprises a circular cross-section. 
     
     
         16 . The switching rocker arm of  claim 15 , wherein at least one of the first arm and the second arm comprises an arcuate latch seat, wherein the latch in an extended position engages the arcuate latch seat to operatively engage the second arm with the first arm. 
     
     
         17 . The switching rocker arm of  claim 14 , further comprising a hydraulic lash adjuster that engages one of the inner arm and the outer arm adjacent one of the first end and the second end of the one of the inner arm and the outer arm, and wherein the hydraulic lash adjuster is a dual feed hydraulic lash adjuster. 
     
     
         18 . The switching rocker arm of  claim 17 , wherein the hydraulic lash adjuster comprises an oil passage fluidly coupled to the latch, and wherein the latch selectively pivotally couples the inner arm to the outer arm in response to one of supplied oil pressure and released oil pressure. 
     
     
         19 . The switching rocker arm of  claim 18 , wherein the latch is disposed adjacent the one of the first end and the second end of the one of the inner arm and the outer arm. 
     
     
         20 . The switching rocker arm of  claim 14 , wherein the first arm comprises a cam-contacting member to engage the first cam, and wherein the cam-contacting member comprises a slider pad. 
     
     
         21 . The switching rocker arm of  claim 20 , further comprising at least one biasing spring disposed between the first arm and the second arm, the at least one biasing spring biasingly coupled to the cam-contacting member.