Abstract: The present disclosure relates to a hydraulic rocker arm for a combustion engine, the rocker arm comprising a valve chamber enclosing a hydraulic valve arrangement configured to at a first state enable oil to flow to and from an oil supply thereby actuating a piston of said rocker arm, and at a second state stopping oil flow between two channels of said rocker arm. The rocker arm further comprise a pressure relief valve in hydraulic communication with said valve chamber, the relief valve being configured to, upon a exceeding a pre-determined load level, discharge oil from the rocker arm. Further, the valve chamber comprises a discharge channel connected to said pressure relief valve, wherein a part of an outer surface of said hydraulic rocker arm forms an inner cavity dimensioned to secure said pressure relief valve (10) to said rocker arm.

Abstract: A valve mechanism system in a hydraulic rocker arm for a combustion engine includes a check valve spring, a check valve ball and a control piston. The spring contacting the ball are arranged in a seat in a recess in the arm. The recess has a first opening to a rocker arm channel connected to a hydraulic element and a second opening to a rocker arm oil supply via a second channel. The piston has a first end with a pin axially aligned with the piston arranged in contact with the ball on the opposite side of the ball from the spring. The ball is movable between a first position allowing oil to flow to and from the oil supply and a second position stopping oil from flowing between the two channels. A control piston spring is arranged on a second end of the piston such that it biases the piston towards the ball.

Abstract: A valve mechanism system in a hydraulic rocker arm (1) for a combustion engine comprises a check valve spring (2) and a check valve ball (3). Said spring (2) is arranged to be in contact with the check valve ball (3) and said spring (2) and ball (3) are arranged in a seat (4) in a recess (5) in the rocker arm (1). The recess (5) has a first opening (6) to a rocker arm channel (7) connected to a hydraulic element and a second opening (8) to a rocker arm oil supply via a second channel (9). The system further comprises a control piston (10) having a first end with a pin (11) axially aligned with the control piston (10) arranged in contact with said check valve ball (3) on the opposite side of the check valve ball (3) from the check valve spring (2). The check valve ball (3) is movable between a first position allowing oil to flow to and from the oil supply and a second position stopping oil from flowing between the two channels (7, 9).

Abstract: Method and apparatus for positioning a coupling means in a gearbox in a first gear position, a second gear position and an intermediate neutral position. The apparatus includes a housing (5) that forms a working cylinder (6), a main piston (7) arranged in the working cylinder (6) in order to interact operationally therewith, and a piston rod (8) connected rigidly to the main piston and extending from a first side thereof out of the housing (5). The piston rod (8) is connected to the coupling means or mechanism (4) outside the housing. The main piston (7) is arranged displaceably between three different positions in the working cylinder that correspond to the first and second gear positions, and the neutral position. An auxiliary piston (11) is also arranged displaceably inside the housing. The auxiliary piston (11) is adapted to operationally interact with the working cylinder and is arranged on a second, opposite side of the main piston relative to the first side.

Abstract: Method and apparatus for positioning a coupling means in a gearbox in a first gear position, a second gear position and an intermediate neutral position. The apparatus includes a housing (5) that forms a working cylinder (6), a main piston (7) arranged in the working cylinder (6) in order to interact operationally therewith, and a piston rod (8) connected rigidly to the main piston and extending from a first side thereof out of the housing (5). The piston rod (8) is connected to the coupling means or mechanism (4) outside the housing. The main piston (7) is arranged displaceably between three different positions in the working cylinder that correspond to the first and second gear positions, and the neutral position. An auxiliary piston (11) is also arranged displaceably inside the housing. The auxiliary piston (11) is adapted to operationally interact with the working cylinder and is arranged on a second, opposite side of the main piston relative to the first side.