A two-stroke engine comprises a first oiling system and a second oiling system. The first oiling system includes a low-pressure pump that distributes oil from a first oil tank to the two-stroke engine. The second oiling system includes a pump mechanically coupled to a crankshaft of the two-stroke engine, wherein the pump distributes oil from a second oil tank to an accessory at a pressure greater than the first oil pressure, wherein oil distributed to the accessory is returned to the second oil tank.

A system for protecting an engine from damage due to vibration while the engine is not operating is provided. The system includes an engine having a crankshaft, at least one piston, at least one bearing, a lubricating fluid source, and a fluid pump associated therewith and a controller operationally connected to and configured to control the fluid pump. When the system is in a first mode, the controller is configured to control the fluid pump in a duty cycle to maintain a predetermined minimum fluid pressure of the lubricating fluid such that a lubricating fluid film is present between the at least one bearing and the crankshaft while the engine is not operating.

According to one embodiment, a rotorcraft includes a body, a rotor blade, a drive system that can be operated to rotate the rotor blade, and an emergency valve control unit. The drive system contains a first gearbox assembly, a second gearbox assembly, a first lubrication system that can deliver lubricant to the first gearbox assembly, and a second lubrication system that can deliver lubricant to the second gearbox assembly. The drive system also contains an emergency valve that can be opened to deliver lubricant from the first lubrication system to the second gearbox assembly. The emergency valve control unit can instruct the emergency valve to open.

A cooling and lubrication system for a motor vehicle drive unit includes a drive unit sump, a first mechanically-driven pump, a second mechanically-driven pump, and an oil/air separator reservoir, among other possible components. The drive unit sump holds drive unit fluid. The first mechanically-driven pump fluidly communicates with the drive unit sump, and the second mechanically-driven pump fluidly communicates with the drive unit sump. The oil/air separator reservoir resides downstream of the first mechanically-driven pump and resides downstream of the second mechanically-driven pump.

In at least one implementation, an engine oil circuit for a vehicle includes first and second oil circuits, and first and second oil pumps. The first oil circuit is communicated with at least one first engine component and the first oil pump is communicated with the first oil circuit to supply fluid flow in the first oil circuit at a first flow rate and a first pressure. The second oil circuit is communicated with at least one second engine component and may be segregated from the first oil circuit. The second oil pump is communicated with the second oil circuit to supply fluid flow in the second oil circuit at a second flow rate and a second pressure. At least one of the second flow rate or the second pressure is different than the first flow rate or the first pressure.

A system. The system includes a valve assembly. The valve assembly includes a first port, a second port fluidically couplable with the first port upon application of negative pressure at the first port, a third port fluidically couplable with the first port upon application of positive pressure at the first port, and a first check valve positioned between the first port and the second port. The system also includes a second check valve fluidically couplable with the third port upon the application of the positive pressure at the first port. The second check valve is positioned external to the valve assembly.

A disclosed lubrication system for a turbofan engine includes a pump for driving lubricant through a lubrication circuit, at least one sensor generating a signal indicative of an engine operating condition and at least one valve for controlling a flow of lubricant through the lubrication circuit. A controller controls operation of the valve to vary the flow of lubricant based on the engine operating condition to maintain lubricant flow within predefined operating limits.

A power unit includes at least one drive source that outputs rotational power to a drive target other than pumps; a first pump rotationally driven by the rotational power of the drive source; a second pump rotationally driven by the rotational power of the drive source, the second pump being different form the first pump; and a power transmission structure that transmits the rotational power of the drive source to the first and second pumps. The power transmission structure includes transmission components and transmits the rotational power to the first pump through one of the transmission components and to the second pump through another of the transmission components.

There is provided a control device for a vehicle oil supply device that includes a mechanical oil pump configured to be rotatable forward and in reverse, an electric oil pump configured to suction oil stored in an oil storage portion that is common to the mechanical oil pump and the electric oil pump, a first filtering member provided to a first strainer of the mechanical oil pump, and a second filtering member provided to second strainer of the electric oil pump. The control device includes a controller configured to control the rotational speed of the electric oil pump. The controller is configured to restrict the rotational speed of the electric oil pump when the mechanical oil pump is rotated in reverse compared to when the mechanical oil pump is rotated forward.

A two-stroke engine comprises a first oiling system and a second oiling system. The first oiling system includes a low-pressure pump that distributes oil from a first oil tank to the two-stroke engine. The second oiling system includes a pump mechanically coupled to a crankshaft of the two-stroke engine, wherein the pump distributes oil from a second oil tank to an accessory at a pressure greater than the first oil pressure, wherein oil distributed to the accessory is returned to the second oil tank.