A variable displacement vane pump has a control slide displaceable within its housing and a first control chamber and a second control chamber for receiving pressurized lubricant. A thermally adjustable control valve is provided in the housing for adjusting pump displacement based on a temperature of the lubricant. In addition to fluid communication channels in the control chambers, at least one vent port is provided in the second chamber. The control valve is configured to control pressure and fluid communication between the chambers along with the control slide. The control valve can help reduce pump displacement at lower temperatures and low engine speeds. At lower temperatures, the second control chamber can be pressurized by the first control chamber. At higher temperatures, the second control chamber can be vented through the control valve and/or the vent port, despite the position of the control slide.

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 machine includes a liquid lubrication system and a shaft, the shaft being rotatable about a rotation axis, the shaft including a first part, a second part engaged coaxially with the first part, and a journal bearing between the first part and the second part, the first part being rotatable relative to the second part about the rotation axis, a helical feature disposed between the first part and the second part and configured to define a helical pump between the first part and the second part, the pump being hydraulically connected to the liquid lubrication system, the journal bearing being disposed adjacent to the helical feature.

Machine provided with a machine element (2) and an oil pump (4) and a motor (3) to drive the machine element (2) and the oil pump (4), whereby the oil pump (4) is provided with a shaft (13) with a rotor (12), whereby the oil pump (4) is provided to pump oil from an oil reservoir (5) via an inlet channel (8) to nozzles that lead into the motor (3) and/or machine element (2) to lubricate and/or cool one or more bearings or other machine components, characterized in that in the inlet channel (8), near the oil pump (4) a dam (16) is provided that is higher than the height (A) of the central axis (18) of the shaft (13) of the oil pump (4) minus the smallest diameter (B) of the rotor (12) of the oil pump (4) divided by two.

A pump stage assembly including at least two pump suction stages and at least one pump pressure stage. The pump suction stages and the pump pressure stage are arranged spaced apart from one another in a pump housing PG and have a common drive shaft. The pump suction stages are formed by a first assembly of intermeshing external gearwheels that lie in a first plane, and the pump pressure stage is formed by a second assembly of intermeshing external gearwheels that lie in a second plane. A first delivery volume flow can be drawn in from a first region of a dry sump by a first pump suction stage, and a second delivery volume flow can be drawn in from a second region of the dry sump by a second pump suction stage. The two delivery volume flows intermix in the pump housing before they reach an oil tank.

A variable displacement vane pump is described. The pump includes a control chamber provided between a housing and a control slide. A pressure-controlled relief valve is in fluid communication with the outlet path and moves to block or unblock a relief port based on output pressure of the lubricant. A feedback channel fluidly connects the control chamber to an inlet path of the pump. The feedback channel further connects to a control port that is connected to a main control valve. The relief valve and control valve are distinct and not fluidly connected. The relief valve moves once the pressure in the outlet path exceeds a predetermined amount, opening the relief port, and thus delivers a portion of the output lubricant to the control chamber via the relief port, thereby pressurizing the control chamber and reducing eccentricity of the pump by displacing the control slide.

An oil pump includes a pump component, a valve container, a valve mechanism, and a circumvention passage. The valve container includes a through hole establishing communication between an inside and an outside of the valve container. The valve mechanism includes: a valve body contained in the valve container; a valve element contained movably in the valve body; a back pressure chamber disposed to face a first valve end of the valve element; a drive mechanism disposed to face a second valve end of the valve element and structured to generate a drive force to move the valve element; and an aperture positioned higher in a vertical direction than the through hole and formed in the valve body so as to establish communication between the back pressure chamber and the inside of the valve container. The circumvention passage establishes communication between the through hole and the aperture.

Lubrication systems of an aircraft engine and associated methods are provided. The lubrication system includes a chamber having a fluid inlet for receiving lubricating fluid into the chamber, and a fluid outlet for draining the lubricating fluid from the chamber. The fluid outlet is disposed on a wall defining part of the chamber. A rotor is disposed inside the chamber and interacts with the lubricating fluid inside the chamber. The rotor is rotatable in a rotation direction about a rotation axis. A perforated baffle is disposed in the chamber for interacting with the lubricating fluid inside the chamber. The perforated baffle includes a base attached to the wall of the chamber. The base of the perforated baffle is disposed at an angular position preceding the fluid outlet relative to the rotation direction of the rotor.

A gerotor pump is provided with a body defining a chamber with cylindrical wall sections and having a fluid inlet and a fluid outlet, and a cover. An internally toothed gear member is supported for rotation within the chamber about a first axis, and has a cylindrical outer wall defining a series of grooves. Each groove has an associated aperture extending through the gear member to an inner surface of the gear member, and is radially positioned between adjacent teeth of the internally toothed gear member. An externally toothed gear member is rotatably supported within the internally toothed gear member about a second axis spaced apart from the first axis, and is coupled for rotation with a drive shaft. The internally toothed gear member and externally toothed gear member cooperate to form a plurality of variable volume pumping chambers therebetween to pump fluid.

A two-cycle internal combustion engine with rear compression chamber, other than that of a crank case. This present engine has valves that can be screwed on the engine block near top dead center, and is actuated by air pressure. This present two-cycle engine yet uses an oil sump similar to that of a four-cycle engine, which eliminating the need to premix oil with the fuel. This present engine has a stationary piston which operates within a movable piston to form a rear-compression chamber. The movable piston has ports near its crown to transfer charge to the combustion chamber. The movable piston also has ports near bottom of its skirt to allow the fuel and air mixture to enter the rear compression chamber. This engine has a piston seat which is adapted to connect the movable piston to the connecting rod.