A cooling cavity is provided inside a piston of an internal combustion engine. Inlet/outlet holes of the cooling cavity are provided in a bottom surface of the piston. A first oil jet that sprays oil toward the inlet/outlet hole, a second oil jet that sprays oil toward a part different from the inlet/outlet hole are included. The first oil jet is caused to spray oil in preference to the second oil jet.

An apparatus for controlling a piston cooling oil jet may include a main gallery supplied with oil, an oil jet gallery defining an oil injection path such that the oil through the main gallery is introduced and is sprayed to a lower portion of a piston, an oil jet valve opening the oil injection path such that the oil supplied to the main gallery is introduced into the oil jet gallery, and a controller electrically connected to the oil jet valve, and determining a target oil pressure through a first factor value corresponding to an RPM and an engine load, a second factor value determined by a predetermined target oil pressure curve, and a third factor value corresponding to an RPM and an oil temperature in the main gallery to control an opening degree of the oil jet valve using the target oil pressure.

An apparatus for controlling a piston cooling oil jet may include a main gallery supplied with oil, an oil jet gallery defining an oil injection path such that the oil through the main gallery is introduced and is sprayed to a lower portion of a piston, an oil jet valve opening the oil injection path such that the oil supplied to the main gallery is introduced into the oil jet gallery, and a controller electrically connected to the oil jet valve, and determining a target oil pressure through a first factor value corresponding to an RPM and an engine load, a second factor value determined by a predetermined target oil pressure curve, and a third factor value corresponding to an RPM and an oil temperature in the main gallery to control an opening degree of the oil jet valve using the target oil pressure.

A piston cooling jet is provided that may include a housing having an interior chamber that receives a fluid from an external source, and a conduit coupled with the housing and fluidly coupled with the interior chamber, the conduit having a bent shape to direct the fluid from the interior chamber of the housing toward an underside of an engine piston head. The piston cooling jet may also include a flow straightening nozzle coupled with the conduit and positioned to straighten flow of the fluid exiting from the conduit via the nozzle toward the underside of the engine piston head, the flow straightening nozzle having internal intersecting walls that intersect along a direction of the flow of the fluid in the conduit and out of the flow straightening nozzle.

A piston cooling jet is provided that may include a housing having an interior chamber that receives a fluid from an external source, and a conduit coupled with the housing and fluidly coupled with the interior chamber, the conduit having a bent shape to direct the fluid from the interior chamber of the housing toward an underside of an engine piston head. The piston cooling jet may also include a flow straightening nozzle coupled with the conduit and positioned to straighten flow of the fluid exiting from the conduit via the nozzle toward the underside of the engine piston head, the flow straightening nozzle having internal intersecting walls that intersect along a direction of the flow of the fluid in the conduit and out of the flow straightening nozzle.

A piston of an internal combustion engine may include a piston head, a piston hub and a connecting rod having a joint end connected via an articulated connection to the piston hub. A reservoir may be provided and configured to receive splash oil for cooling the piston head. The reservoir may include at least one splash outlet directed towards the piston head. The reservoir may be arranged at the joint end of the connecting rod on a side facing towards the piston head.

Provided is a valve housing configured to be inserted into an insertion hole that extends in a direction approximately orthogonal to an extending direction of an oil path and configured to be freely movable along an extending direction of the insertion hole. When an oil jet switching valve is closed, the tip end portion of the valve housing is configured to be pressed to the inner wall surface of the oil path by receiving an energized force from an energizing unit.

Provided is a valve housing configured to be inserted into an insertion hole that extends in a direction approximately orthogonal to an extending direction of an oil path and configured to be freely movable along an extending direction of the insertion hole. When an oil jet switching valve is closed, the tip end portion of the valve housing is configured to be pressed to the inner wall surface of the oil path by receiving an energized force from an energizing unit.

A structure for attaching an oil jet valve includes a bracket secured to an internal combustion engine with a seal member, an attachment concavity extending through the interior of the bracket, an insertion hole extending through the interior of the internal combustion engine, an oil jet valve, a first stepped part formed in the oil jet valve, a second stepped part formed in the attachment concavity, and an interlocking member. The width of a wide part of the first stepped part is less than the width of a narrow part of the second stepped part. The width of the wide part of the first stepped part is less than the width of a portion, of the inner surface of the attachment concavity, that faces the wide part of the first stepped part.

A pilot operated piston oil cooling jet control valve configured to be in communication with a main oil galley, an oil pan, and a cooling jet is provided. The pilot operated piston oil cooling jet control valve includes a valve body, a pilot valve, and a main stage poppet. The pilot valve is arranged within the valve body and includes a solenoid armature movable between a first position and a second position and a pilot poppet movable between a pilot open position where flow is provided to the oil pan and a pilot closed position where flow is inhibited to the oil pan. The main stage poppet is arranged within the valve body and is movable between a closed position where flow is inhibited to the cooling jet and an open position where flow is provided to the cooling jet.