Abstract: A method of controlling a hydraulic valve includes putting a first control chamber under pressure and putting a second control chamber to return so as to cause a slide to move into one of two end positions, putting a second control chamber under pressure and putting the first control chamber to return, thereby causing the slide to move into the other one of the two end positions. An intermediate step of applying pressure to the one of the first or second control chamber that was connected to return can be provided so that both control chambers are maintained simultaneously under pressure for a determined length of time.

Abstract: The invention provides a hydraulic circuit for feeding an actuator (1) comprising first and second chambers (5, 6), the circuit comprising a slide valve (10) with a slide (16) that is movable between first and second extreme positions (18, 19) on either side of a stable central position (17) so that: in the central position, it connects the chambers (5, 6) of the actuator to a return port; in the first extreme position (18), it connects the first chamber (5) to a feed port and the second chamber to the return port; and in the second extreme position (19), it connects at least the second chamber (6) to the feed port. According to the invention, the hydraulic circuit includes pressure-maintaining means (20) for maintaining pressure in the first chamber of the actuator while the slide is passing through the central position on being moved from the first extreme position to the second extreme position.

Abstract: The invention provides a hydraulic circuit for feeding an actuator (1) comprising first and second chambers (5, 6), the circuit comprising a slide valve (10) with a slide (16) that is movable between first and second extreme positions (18, 19) on either side of a stable central position (17) so that: in the central position, it connects the chambers (5, 6) of the actuator to a return port; in the first extreme position (18), it connects the first chamber (5) to a feed port and the second chamber to the return port; and in the second extreme position (19), it connects at least the second chamber (6) to the feed port. According to the invention, the hydraulic circuit includes pressure-maintaining means (20) for maintaining pressure in the first chamber of the actuator while the slide is passing through the central position on being moved from the first extreme position to the second extreme position.

Abstract: A method of controlling a hydraulic valve includes putting a first control chamber under pressure and putting a second control chamber to return so as to cause a slide to move into one of two end positions, putting a second control chamber under pressure and putting the first control chamber to return, thereby causing the slide to move into the other one of the two end positions. An intermediate step of applying pressure to the one of the first or second control chamber that was connected to return can be provided so that both control chambers are maintained simultaneously under pressure for a determined length of time.

Abstract: A hydraulic actuator containing a hollow body defining a cylindrical cavity and a rod which is mounted to slide within the body along a sliding axis between two end positions and which is integral with a piston sliding in a sealed manner within the cylindrical cavity in order to define two chambers. The rod defines an interior passage, connecting the two chambers, which has a valve comprising a shut-off member which is returned towards a seat and closes the passage. The rod receives a push member which can move relative to the rod between a position apart from the shut-off member and a position forcing the shut-off member to open. The push member is constrained, when the rod reaches the end of its stroke, by the push member engaging with a portion of the hollow body.

Abstract: A hydraulic circuit for actuating an undercarriage, the circuit comprising: a feed line for feeding fluid and a return line; at least one door selector connected to the feed and return lines, the selector feeding door service lines, including an opening line and a closing line for opening and closing the doors; at least one undercarriage selector connected to the feed and return lines, feeding undercarriage service lines including a deployment line and a raising line for deploying and raising the undercarriage; and a door unhooking line and an undercarriage unhooking line. The door unhooking line is connected to at least one undercarriage service line while the undercarriage unhooking line is connected to at least one door service line, the circuit also including means for connecting the door service lines together during a door opening stage, and means for connecting the undercarriage service lines together during an undercarriage deployment stage.

Abstract: An actuator comprising a body in which a rod is mounted to slide, the actuator including a screw extending inside the rod to co-operate with a nut secured to the rod, the screw being driven in rotation by a motor. The rod is associated with a piston that slides in a cavity of the body so as to define two chambers therein, the chambers being filled with hydraulic fluid and being put into communication via fluid transfer means fitted with at least one regulator member adapted to throttle the fluid expelled from one of the chambers, in at least one travel direction of the rod.

Abstract: The invention relates to a hydraulic valve comprising a body in which a bore is formed in order to receive a sleeve that includes sealing seats that cooperate with a wall of the bore to define hydraulically isolated chambers that are connected to hydraulic ports in the body, the sleeve including connection holes in order to connect at least certain chambers with the inside of the sleeve and receiving a movable element that is slidable between two end positions in order to slide in leaktight manner against an inside wall of the sleeve, wherein the sleeve includes at least one regulator hole that opens out inside the sleeve in such a manner as to be the first bore to be uncovered or the last bore to be blocked by one of the fitted portions of the movable element when said element slides from one position to another, said fitted portion having at least one face portion that presents a setback that passes over the regulator hole.

Abstract: A hydraulic actuator comprising a hollow body (1, 3) defining a cylindrical cavity and a rod (5) which is mounted to slide within the body along a sliding axis between two end positions and which is integral with a piston sliding in a sealed manner within the cylindrical cavity in order to define two chambers (C1, C2). The rod defines an interior passage, connecting the two chambers, which has a valve (20) comprising a shut-off member (21) which is returned towards a seat (22) and closes the passage. The rod receives a push member (15, 26) which can move relative to the rod between a position apart from the shut-off member (21) and a position forcing the shut-off member to open. The push member is constrained, when the rod reaches the end of its stroke, by the push member engaging with a portion (3) of the hollow body.

Abstract: A hydraulic circuit for actuating an undercarriage, the circuit comprising: a feed line for feeding fluid and a return line; at least one door selector connected to the feed and return lines, the selector feeding door service lines, including an opening line and a closing line for opening and closing the doors; at least one undercarriage selector connected to the feed and return lines, feeding undercarriage service lines including a deployment line and a raising line for deploying and raising the undercarriage; and a door unhooking line and an undercarriage unhooking line. The door unhooking line is connected to at least one undercarriage service line while the undercarriage unhooking line is connected to at least one door service line, the circuit also including means for connecting the door service lines together during a door opening stage, and means for connecting the undercarriage service lines together during an undercarriage deployment stage.

Abstract: The invention relates to a hydraulic valve comprising a body in which a bore is formed in order to receive a sleeve that includes sealing seats that cooperate with a wall of the bore to define hydraulically isolated chambers that are connected to hydraulic ports in the body, the sleeve including connection holes in order to connect at least certain chambers with the inside of the sleeve and receiving a movable element that is slidable between two end positions in order to slide in leaktight manner against an inside wall of the sleeve, wherein the sleeve includes at least one regulator hole that opens out inside the sleeve in such a manner as to be the first bore to be uncovered or the last bore to be blocked by one of the fitted portions of the movable element when said element slides from one position to another, said fitted portion having at least one face portion that presents a setback that passes over the regulator hole.

Abstract: The invention relates to an actuator comprising a body in which a rod is mounted to slide, the actuator including a screw extending inside the rod to co-operate with a nut secured to the rod, the screw being driven in rotation by a motor. According to the invention, the rod is associated with a piston that slides in a cavity of the body so as to define two chambers therein, the chambers being filled with hydraulic fluid and being put into communication via fluid transfer means fitted with at least one regulator member adapted to throttle the fluid expelled from one of the chambers, in at least one travel direction of the rod.

Abstract: A nozzle and a device for the application of the nozzle are disclosed. In the nozzle a mechanism is provided so that the dimensions of the hole for the flow of fluid can be varied according to the pressure differential between the inlet and the outlet. The above can be applied to the making of nozzles and/or devices, the delivery rate of which is directly proportionate to the differential pressure between the inlet and the outlet.