A device for stabilizing pressure inside a gear's housing or a wheel's hub includes a bladder, and a conduit coupled to the bladder and coupleable to a volume containing a lubricant. The bladder includes a chamber having a volume, and is configured such that the chamber's volume increases as a fluid enters the chamber, and decreases as fluid leaves the chamber. The conduit includes a first end positionable adjacent the lubricant containing volume, a second end coupled with the bladder, and a passage between the first and second ends, and is configured to hold fluid disposed in the passage and direct the fluid between the first and second ends. When the conduit is coupled to the lubricant containing volume, the volume of the bladder's chamber, the passage of the conduit and the lubricant containing volume are isolated from the ambient environment.

A method for lubricating a sealed bearing providing a first ring and a second ring capable of rotating concentrically relative to one another, and seals delimiting together with the first and second rings a sealed chamber. The method includes a removing a first predetermined quantity of lubricant from the sealed chamber until the pressure in the sealed chamber reaches a first pressure value, and then injecting a second predetermined quantity of lubricant in the sealed chamber until the pressure in the sealed chamber reaches a second pressure value, the first pressure value and the second pressure value being determined so that the pressure inside the sealed chamber remains within a predetermined interval, the boundaries of the interval being determined according to characteristics of the seals so that the sealed chamber remains waterproof to the lubricant when lubricant is removed from or injected in the sealed chamber.

The invention relates to an oil system (7) comprising a pump arrangement (11); a first gallery (13) for providing oil to a first engine site (14); a second gallery (15) for providing oil to a second engine site (16); a second gallery flow control device (25) for controlling flow of oil from the pump arrangement (11) to the second gallery (15); control circuitry (5); a first pressure sensor (27) for sensing the oil pressure in the first gallery (13); and a second pressure sensor (29) for sensing the oil pressure in the second gallery (15). The oil system (7) is controllable between: a first state in which the control circuitry (5) controls the second gallery flow control device (25) to an open state, and controls an oil pressure in the second gallery (15) by controlling the pump arrangement (11); and a second state in which the control circuitry (5) controls an oil pressure in the first gallery (13) by controlling the pump arrangement (11), and controls the oil pressure in the second gallery (15) by controlling the second gallery flow control device (25).

This oil pressure control device is provided with: an oil cooler which cools engine oil circulating through a hydraulic circuit of an engine; a bypass oil passage which bypasses the oil cooler; an oil cooler bypass valve by means of which an engine oil flow passage is switched between the oil cooler and the bypass oil passage; an oil pressure sensor which measures a first oil pressure, which is the oil pressure of engine oil; and a valve control unit which controls opening and closing of the oil cooler bypass valve to reduce the magnitude of a difference between the first oil pressure and a second oil pressure, which is a target oil pressure determined on the basis of the rotational speed of the engine and a fuel injection quantity.

The invention relates to a fluid circuit (3) comprising: a supply line (5) for carrying a fluid from a pump (4) connected to a fluid tank (2) to an equipment (8), the supply line having a portion which is divided into a main line (10) including a heat exchanger (13), and a by-pass line (15) for by-passing said heat exchanger; a first valve (31) for controlling the respective fluid flows in the main line (10) and in the by-pass line (15), and a first control device (33) for controlling the first valve (31) depending on a first parameter (T) of the fluid; a pressure regulation circuit for carrying fluid from the supply line (5) towards the fluid tank (2), said pressure regulation circuit comprising a pressure regulation valve (23) for controlling the flow of fluid directed back to the fluid tank (2); wherein the pressure regulation circuit comprises: a first recirculation line (21) branching from the supply line (5) downstream from the by-pass line outlet (17); a second recirculation line (22) branching from the supply line (5) upstream from the by-pass line inlet (16); a second valve (32) for controlling the respective fluid flows in the first recirculation line (21) and in the second recirculation line (22), and a second control device (33) for controlling the first valve (31) depending on a second parameter (T) of the fluid.

A gas turbine engine includes a fan, a compressor, a combustor, a turbine, a bypass duct, and a bearing compartment assembly. The bearing compartment assembly includes a fluid pump, a compartment, a fluid line between the fluid pump and the compartment, and a damper check valve located in the fluid line. The damper check valve is a unitary, monolithic component that is configured to restrict a reverse flow from the compartment to the fluid pump substantially more than the damper check valve restricts a standard flow from the fluid pump to the compartment.

A device for stabilizing pressure inside a gear's housing or a wheel's hub includes a bladder, and a conduit coupled to the bladder and coupleable to a volume containing a lubricant. The bladder includes a chamber having a volume, and is configured such that the chamber's volume increases as a fluid enters the chamber, and decreases as fluid leaves the chamber. The conduit includes a first end positionable adjacent the lubricant containing volume, a second end coupled with the bladder, and a passage between the first and second ends, and is configured to hold fluid disposed in the passage and direct the fluid between the first and second ends. When the conduit is coupled to the lubricant containing volume, the volume of the bladder's chamber, the passage of the conduit and the lubricant containing volume are isolated from the ambient environment.

A lubrication system including a drive fluid chamber and a lubricant chamber. A first movable member is movable from a first position to a second position within the drive fluid chamber in response to drive fluid pressure acting on the first movable member. A second movable member is movable between a first position and a second position within the lubricant chamber and is operatively coupled to the first movable member. A biasing member is positioned to bias the first movable member toward the first position. A relief valve is associated with the first movable member and, when the relief valve in an open state, the drive fluid pressure acting on the first movable member is reduced such that the biasing member moves the first movable member to the first position within the drive fluid chamber.

The invention relates to a lubrication device for a turbine engine, comprising an oil intake pipe (23) provided with a pump (24) for supplying oil and control means (25) located downstream from the supply pump (24), a supply pipe (26) intended for supplying oil to a member to be lubricated and a recirculation pipe (27), the control means (25) making it possible to direct all or part of the flow of oil from the intake pipe (23) towards the supply pipe (26) and/or towards the recirculation pipe (27), the pump (24) being driven by at least one rotary member of an accessory gearbox of the turbine engine.

A battery cooling system includes: a circulation circuit configured to circulate common oil to a transaxle, a battery, and an oil cooler; a first electric oil pump that is disposed in a first oil passage; a second electric oil pump that is disposed in a second oil passage; and a controller configured to control the first electric oil pump and the second electric oil pump. The controller is configured to operate the first electric oil pump and stop the second electric oil pump when a temperature of the battery is equal to or lower than a first predetermined value, and stop the first electric oil pump and operate the second electric oil pump when the temperature of the battery is higher than the first predetermined value.