Abstract: Emergency start-up device for a turboshaft engine of a helicopter, comprising: a hydraulic motor which is mechanically connected to said turboshaft engine; a hydropneumatic store which is connected to said hydraulic motor by a hydraulic circuit for supplying pressurized liquid to said hydraulic motor; and a hydraulic valve which has controlled quick opening, arranged on the hydraulic circuit between said store and said hydraulic motor, and is suitable for being placed on command at least in an open position in which the liquid can supply said hydraulic motor, or in a closed position in which said hydraulic motor is no longer supplied with pressurized liquid.

Abstract: Emergency start-up device for a turboshaft engine of a helicopter, comprising: a hydraulic motor which is mechanically connected to said turboshaft engine; a hydropneumatic store which is connected to said hydraulic motor by a hydraulic circuit for supplying pressurised liquid to said hydraulic motor; and a hydraulic valve which has controlled quick opening, arranged on the hydraulic circuit between said store and said hydraulic motor, and is suitable for being placed on command at least in an open position in which the liquid can supply said hydraulic motor, or in a closed position in which said hydraulic motor is no longer supplied with pressurised liquid.

Abstract: A hydraulic pump with two rotation directions has axial pistons bearing against a swashplate, the pump with a head having two chambers to be connected to a high-pressure circuit and to a low-pressure circuit. A port plate in the form of a flat plate is arranged between a rotary barrel and the head and has two identical ports passing through the thickness of the flat plate. The port plate pivots about an axis to be able to occupy two angular positions according to the direction of rotation of the pump. The pump has a hydraulic-control device for controlling the angular position of the port plate and is able automatically to bring about a change in angular position of the port plate when the direction of rotation of the pump is reversed, under the effect of a pressure differential between the two chambers of the head.

Abstract: A hydraulic pump having a plurality of pistons sliding in bores formed in a barrel mounted in rotation in a casing of the pump, the barrel bearing against a distribution port plate borne by a cylinder head. Two drainage channels place an inner space of the casing in respective communication with two suction/delivery orifices of the cylinder head. Each drainage channel is provided with a valve able to close the drainage channel in response to an overpressure in the suction/delivery orifice such that, according to the direction of rotation of the pump, the inner space of the casing is in communication through one of the drainage channels with the suction line; whereas the communication through the other drainage channel between the delivery side and the inner space of the casing is closed.

Abstract: A hydraulic motor that can be operated in both directions, the hydraulic motor comprising two two-way hydraulic ports each of which can be connected, selectively depending on the direction of rotation in which the motor is to be actuated, either to a source of pressurized liquid or to a device for collecting the liquid at a lower pressure, the hydraulic motor comprising a drain port communicating with an interior space of the motor case, which comprises: an intermediate pipe into which the drain pipe of the case opens, a first non-return valve positioned between the intermediate pipe and a first two-way hydraulic port and able to open toward the first two-way hydraulic port; and a second non-return valve positioned between the intermediate pipe and a second two-way hydraulic port and able to open toward the second two-way hydraulic port.