Torsion assembly for controllably providing torque to a camshaft

Abstract

A torsion assembly for providing controllable torsion to a camshaft, including: a spring assembly including a first spring; and, a contact element arranged to engage at least one lobe for the camshaft. For a locked mode: the contact element is arranged to be displaced by the at least one cam lobe; the contact element is arranged to compress the first spring; and the first spring is arranged to impart a first torque to the camshaft via the contact element. For an unlocked mode, the contact element is arranged to be displaced by the at least one cam lobe and the contact element is arranged to impart a second torque, less than the first torque, to the cam shaft via the contact element.

1 . A torsion assembly for providing controllable torsion to a camshaft, comprising:
 a spring assembly including a first spring; and,   a contact element arranged to engage at least one lobe for the camshaft, wherein:
 for a locked mode:
 the contact element is arranged to be displaced by the at least one cam lobe; 
 the contact element is arranged to compress the first spring; and, 
 the first spring is arranged to impart a first torque to the camshaft via the contact element; and, 
 
 for an unlocked mode:
 the contact element is arranged to be displaced by the at least one cam lobe; and, 
 the contact element is arranged to impart a second torque, less than the first torque, to the cam shaft via the contact element. 
 
   
     
     
         2 . The torsion assembly of  claim 1 , further comprising:
 a lock element including a non-displaceable distal end, wherein:   the contact element includes a switching roller finger follower, the switching roller finger follower including:
 a bearing arranged to contact the at least one camshaft lobe; and, 
 an arm:
 connected to the bearing; 
 disposed about a shaft; and 
 including:
 a first portion with a first end engaged with the spring assembly; and, 
 a second portion including a second end engaged with the distal end of the lock element, wherein: 
 
 
 for the locked mode:
 the bearing is arranged to be displaced by the at least one lobe; 
 the arm is arranged to non-rotatably connect to the shaft; 
 the second end is arranged to pivot on the distal end; and, 
 the first end is arranged to compress the first spring; and, 
 
 for the unlocked mode:
 the bearing is arranged to be displaced by the at least one lobe; 
 rotation of the arm with respect to the shaft is enabled; 
 the arm is arranged to rotate with respect to the shaft; 
 the first end is arranged to pivot on the spring assembly; and, 
 the second end is arranged to compress the second spring. 
 
   
     
     
         3 . The torsion assembly of  claim 2 , wherein for the unlocked mode, the first spring is not compressed. 
     
     
         4 . The torsion assembly of  claim 1 , wherein:
 the contact element includes a switching roller finger follower;   the switching roller finger follower includes an arm disposed about a shaft;   the arm includes:
 a first end engaged with the spring assembly; and, 
 a second end arranged to engage the at least one lobe for the camshaft; 
   for the locked mode:
 the arm is arranged to non-rotatably connect to the shaft; 
 the at least one lobe for the camshaft is arranged to displace the second end; and, 
 the first end is arranged to compress the first spring; and, 
 for the unlocked mode:
 the at least one lobe for the camshaft is arranged to displace the second end; and; 
 the arm is arranged to rotate about the shaft. 
 
   
     
     
         5 . A torsion assembly for providing controllable torsion to a camshaft, comprising:
 a housing;   a pressure chamber at least partially enclosed by the housing;   at least one pin partially disposed in the pressure chamber;   a first spring engaged with the at least one pin;   a second spring engaged with the housing;   a third spring; and,   a piston engaged with the second and third springs, wherein:
 for a locked mode:
 the first spring is arranged to displace the at least one pin to block displacement of the piston with respect to the housing; 
 the at least one cam lobe is arranged to displace the housing in the first direction to compress the third spring in the first direction to generate a first torque; and, 
 the housing is arranged to transmit the first torque to the camshaft; 
 
 for an unlocked mode:
 the pressure chamber is arranged to be pressurized to displace the at least one pin to enable displacement of the housing with respect to the piston; 
 the at least one cam lobe is arranged to displace the housing to compress the second spring in the first direction to generate a second torque, less than the first torque; and, 
 the housing is arranged to transmit the second torque to the camshaft. 
 
   
     
     
         6 . The torsion assembly of  claim 5 , wherein:
 the housing and the piston form a chamber; and,   the second spring is disposed in the chamber and engaged with the housing.   
     
     
         7 . The torsion assembly of  claim 6 , wherein:
 the piston includes a first component and at least one second component;   the at least one pin is disposed between the first component and the at least one second component; and,   for the locked mode, the at least one pin displaces with the piston.   
     
     
         8 . The torsion assembly of  claim 6 , wherein in the unlocked mode, the housing is displaceable with respect to the piston.