A method for producing a reduced friction sliding surface on a machine element includes applying a coating comprising amorphous carbon to a surface of the machine element and locally heating the coating with a laser. The coating is heated to a temperature below an evaporation temperature of the coating to achieve a local volumetric increase in the coating and a local increase in a layer thickness of the coating. A surface structure of the coating includes a multiplicity of elevations resulting from a local phase transformation of the coating from amorphous carbon into graphite due to the locally heating.

A method for producing a reduced friction sliding surface on a machine element includes applying a coating comprising amorphous carbon to a surface of the machine element and locally heating the coating with a laser. The coating is heated to a temperature below an evaporation temperature of the coating to achieve a local volumetric increase in the coating and a local increase in a layer thickness of the coating. A surface structure of the coating includes a multiplicity of elevations resulting from a local phase transformation of the coating from amorphous carbon into graphite due to the locally heating.

Even in the case where, due to distortion (undulation) or the like of an end surface of an adjusting screw abutting on a valve stem end, there exists a non-linear undulation movement amount in a movement amount of the end surface with respect to a rotation return angle of the adjusting screw, the undulation movement amount is continuously measured, and a screw return movement amount based on a screw pitch and on the rotation return angle is continuously calculated, and, when a total movement amount of the undulation movement amount and the screw return movement amount has attained a prescribed clearance, return rotation is ended.

Even in the case where, due to distortion (undulation) or the like of an end surface of an adjusting screw abutting on a valve stem end, there exists a non-linear undulation movement amount in a movement amount of the end surface with respect to a rotation return angle of the adjusting screw, the undulation movement amount is continuously measured, and a screw return movement amount based on a screw pitch and on the rotation return angle is continuously calculated, and, when a total movement amount of the undulation movement amount and the screw return movement amount has attained a prescribed clearance, return rotation is ended.

A method for producing a reduced friction sliding surface on a machine element includes applying a coating comprising amorphous carbon to a surface of the machine element and locally heating the coating with a laser. The coating is heated to a temperature below an evaporation temperature of the coating to achieve a local volumetric increase in the coating and a local increase in a layer thickness of the coating. A surface structure of the coating includes a multiplicity of elevations resulting from a local phase transformation of the coating from amorphous carbon into graphite due to the locally heating.

A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

The invention relates to a method for producing a sliding surface on a machine element, in particular a cam follower, wherein the machine element is first provided with a coating on at least part of the surface of the machine element, into which coating a surface structure is then introduced by laser structuring. In order to be able to introduce a surface structure that does not penetrate the coating even in the case of low layer thicknesses (s1) of the coating, the introduction of the surface structure is performed by laser interference structuring.

The invention relates to a method for producing a sliding surface on a machine element, in particular a cam follower, wherein the machine element is first provided with a coating on at least part of the surface of the machine element, into which coating a surface structure is then introduced by laser structuring. In order to be able to introduce a surface structure that does not penetrate the coating even in the case of low layer thicknesses (s1) of the coating, the introduction of the surface structure is performed by laser interference structuring.

An exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode includes: a rocker shaft that defines a pressurized oil supply conduit; a rocker arm that receives the rocker shaft and rotates around the rocker shaft, the rocker arm including a rocker arm oil supply passage defined in the rocker arm; a valve bridge for engaging a first exhaust valve and a second exhaust valve; a hydraulic lash adjuster assembly, disposed on the rocker arm, including a first plunger body movable between a first position and a second position; and a check valve, disposed on the rocker arm, including an actuator for selectively releasing pressure in the hydraulic lash adjuster assembly. In the engine braking mode, by rotation of the rocker arm the pressurized oil supply conduit is brought into fluid communication with the rocker arm oil supply passage.