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EP-4735750-A1 - LOST-MOTION ACTUATING DEVICE FOR A THRUST REVERSER

EP4735750A1EP 4735750 A1EP4735750 A1EP 4735750A1EP-4735750-A1

Abstract

The invention relates to an actuating device (1) for an aircraft thrust reverser system (3) comprising at least one thrust reverser device (2), the actuating device (1) comprising at least one motorized drive unit (10) situated on an upstream side of a first lost-motion lock (12a) and designed to actuate an input shaft (11) of this first lock (12a), the first lock being designed, when unlocked, to actuate an output shaft driving a flexible synchronization shaft (13) situated on a downstream side, and the actuating device (1) further comprising at least one first movable jack rod (14b) which is mechanically connected to the flexible synchronization shaft and secured to a movable element of the thrust reverser device (2), the first movable rod belonging to a first set of movable rods which is associated with the first lock (12a).

Inventors

  • DEMARES, Florian
  • MORADELL-CASELLAS, PIERRE
  • Peyron, Vincent Jean-François

Assignees

  • Safran Nacelles

Dates

Publication Date
20260506
Application Date
20240624

Claims (9)

  1. 1. ^Actuation device (1) for a thrust reverser system (3) for an aircraft comprising at least one thrust reverser device (2), said actuation device (1) comprising at least one motorized drive unit (10) located on a so-called upstream side of a first lost-motion lock (12a) and adapted to actuate an input shaft (11) of said first lost-motion lock (12a), said first lock being adapted to, when unlocked, actuate an output shaft driving a flexible synchronization shaft (13) located on a so-called downstream side, opposite said upstream side, and said actuation device (1) further comprising at least one first movable cylinder rod (14b), mechanically connected to said flexible synchronization shaft and secured to a movable element of said thrust reverser device (2), said first movable rod belonging to a first set of movable rods associated with said first lost-motion lock (12a).
  2. 2. Device according to the preceding claim, in which said output shaft is directly connected to a second movable rod (14a) of the cylinder, also integral with a movable element of said thrust reverser device (2) and belonging to said first set of movable rods.
  3. 3. Actuating device (1) according to one of the preceding claims, in which said motorized drive unit (10) is adapted to actuate a second lost-motion lock (12b), adapted to actuate a second set of movable rods (14c, 14d).
  4. 4. Device according to the preceding claim, in which said thrust reverser device (2) comprises two movable elements (2a, 2b) and in which said first assembly (14a, 14b) is integral with a first movable element (2a), and said second assembly (14c, 14d) is integral with a second movable element (2b).
  5. 5. Actuating device (1) according to one of claims 3 or 4, in which said first and second locks (12a, 12b) each comprise a preload arrangement (17a, 17b) provided to oppose any movement when an imposed force is less than a preload threshold.
  6. 6. Actuating device (1) according to one of claims 3 to 5, in which a brake (20) is inserted between said first lock (12a) and said second lock (12b).
  7. 7. Actuating device (1) according to one of claims 3 to 6, further comprising a flexible coupling shaft (18) capable of transmitting forces between the first and second sets of movable rods.
  8. 8. Thrust reversal system (3) comprising a thrust reversal device (2) and an actuating device (1) according to one of claims 1 to 7.
  9. 9. Nacelle (100) for an aircraft comprising at least one thrust reversal system (3) according to the preceding claim.]

Description

Lost motion actuation device for thrust reverser [0001] FIELD OF THE INVENTION [0002] The present invention relates to a thrust reversal system for an aircraft. [0003] An aircraft, in particular an airplane, is typically powered by turbomachines, in particular turbojets, each housed in nacelles designed to channel the air flows generated by the turbomachine. Such a nacelle may also house various equipment, such as a thrust reverser system. [0004] The role of a thrust reverser is to facilitate the landing of the aircraft. In operation, the thrust reverser system allows part of the airflow to be redirected forward, which generates a thrust opposite to the direction of movement of the aircraft and thus helps to reduce its speed. This system thus complements the braking of the wheels. [0005] There are different types of thrust reverser systems. These include door reversers and grid reversers. [0006] A thrust reversal system relies on a mechanism for actuating movable elements such as cowls or doors, which are movable between two positions, in order to engage or disengage the thrust reversal function. [0007] Generally speaking, thrust reverser systems (with doors or grids) are based on the movement of a cowl, in particular in translation for a grid reverser, by means of actuators. The translation is generally in a direction substantially parallel to a longitudinal axis of the nacelle. [0008] A distinction can be made between single-piece cowls (or "O-duct" according to the English terminology) and "D-duct" cowls formed of two half-cowls. According to this terminology, the letters O and D refer to the shape of the single-piece cowl (annular or substantially annular) or, respectively, of a half-cowl. Document FR 2 914 700 describes in more detail a single-piece cowl for a thrust reverser system. [0009] The translation of the hood is typically carried out by means of a plurality of actuators. Typically, 4 or 6 actuators can be provided per hood, or 2 or 3 per half-hood in the case of a “D-duct” architecture. [0010] These actuators are typically actuating cylinders, the movable rod of which is integral with the hood or half-hood. [0011] Obviously, it is crucial to avoid any accidental sliding of the cylinder, because opening the hood at an inopportune moment (during the flight phase, in particular) can have extremely serious consequences for the aircraft and fatal consequences for its crew. [0012] Safety devices are therefore necessary, in particular locking systems acting directly on the cylinders, in order to prevent the unwanted opening of the hood. The rules for certifying a flight reverser require the installation of three locks, including two so-called primary locks, for each hood or each half-hood. The third lock is independent of the first two so as to prevent the same order from being able to open the reverser in flight in an unwanted manner. [0013] Patent application FR3008741 describes integrating a lock directly into the drive cylinder, by means of a lost motion drive cylinder. [0014] This “lost movement” mechanism consists of a first part of an input movement being used to unlock the lock, then, once the lock is unlocked, the subsequent movement being used to deploy the movable rod. [0015] When closing the thrust reverser, the movable rod retracts into the cylinder body, then engages the locking system again when the first part of the input screw excursion is reached. Movement between the locking position and the closed stop is not prohibited. [0016] In patent application FR3008741, it is proposed to have a single motorized drive unit (or PDU for “Power Drive Unit”) in English) which supplies two drive cylinders associated with the same half-hood. Each cylinder is also associated with a lost movement lock. [0017] This proposal is not entirely satisfactory because it has been noted through experience that the locks do not necessarily unlock synchronously, which results in the hood not always opening smoothly but rather by "jerks". Furthermore, and above all, this proposal requires having one lock per cylinder, which is very penalizing in terms of manufacturing cost, maintenance, and mass. [0018] SUMMARY OF THE INVENTION [0019] One of the aims of the invention is to improve the state of the art. [0020] It makes it possible to reduce the mass of the thrust reversal system, and the corresponding costs, by pooling a single lock for several movable cylinder rods, while avoiding the unwanted unlocking of this lock by the forces coming from the different movable rods downstream. [0021] For these purposes, according to a first aspect, the present invention can be implemented by an actuating device for an aircraft thrust reverser system comprising at least one thrust reverser device, said actuating device comprising at least one motorized drive unit located on a so-called upstream side of a first lost motion lock and adapted to actuate an input shaft of said first lost motion lock, said first lock being adapted