US 12,146,427 B2
Switchable rocker arm for controlling the lift of a valve bridge or a single valve of valve train group of an internal combustion engine and valve train group comprising at least a such switchable rocker arm
Davide Ferrario, Adro (IT); Francesco Mega, Adro (IT); and Matteo Magni, Adro (IT)
Assigned to STREPARAVA S.P.A. CON SOCIO UNICO, Adro (IT)
Appl. No. 18/247,005
Filed by STREPARAVA S.P.A. CON SOCIO UNICO, Adro (IT)
PCT Filed Sep. 21, 2021, PCT No. PCT/IB2021/058597
§ 371(c)(1), (2) Date Mar. 28, 2023,
PCT Pub. No. WO2022/069998, PCT Pub. Date Apr. 7, 2022.
Claims priority of application No. 102020000023077 (IT), filed on Sep. 30, 2020.
Prior Publication US 2023/0366335 A1, Nov. 16, 2023
Int. Cl. F01L 13/00 (2006.01); F01L 1/18 (2006.01); F01L 1/24 (2006.01); F01L 1/26 (2006.01); F01L 13/06 (2006.01)
CPC F01L 13/0005 (2013.01) [F01L 1/181 (2013.01); F01L 1/2411 (2013.01); F01L 1/267 (2013.01); F01L 13/06 (2013.01); F01L 2001/186 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A switchable rocker arm for controlling a lift of a valve bridge or of a single valve of a valve train group of an internal combustion engine; the switchable rocker arm being rotatable around a first axis and comprising:
a cam body configured to be driven in rotation by a cam about the first axis;
a valve body configured to act on the valve bridge or on the single valve;
wherein the switchable rocker arm is selectively switchable between a first configuration, in which the rotation of the cam body about the first axis generates a movement of the valve body about the first axis, and a second configuration in which the rotation of the cam body about the first axis does not generate any movement of the valve body;
characterized in that
inside the cam body or the valve body a cylinder is obtained for housing a sliding shaped piston movable between a first position and a second position; and
the switchable rocker arm comprising a locking device which cooperates with the shaped piston and configured in such a way that:
in the first position of the piston the locking device acts simultaneously on the cam body and on the valve body so as to constrain the switchable rocker arm in the first configuration; and
in the second position of the piston the locking device enters the cylinder so that the switchable rocker arm is in the second configuration;
wherein inside the cylinder a mobile collar is provided around a stem of the piston, the piston and the collar being configured so that for passing from the first to the second position the piston performs a first movement forced by hydraulically driven movement of the collar and thereafter the piston performs a second movement with the collar fixed forced by the penetration of the locking device inside the cylinder.