Actuating device for moving a movable cover of a thrust reverser

Abstract

An actuating device for moving a mobile cap of a thrust reverser, which includes: an actuator having a first element, such as a screw, and a second element, such as a nut, collaborating with the first element in such a way that turning the first element causes the second element to move in a translational movement. A locking piece is rotationally mobile between a locked position in which the locking piece prevents the first element from turning, and an unlocked position in which the locking piece allows the first element to turn. An unlocking piece is rotationally mobile between an active position in which the unlocking piece urges the locking piece towards the unlocked position and a passive position in which the unlocking piece allows the locking piece to return to the locked position.

Claims

1. An actuating device (1) for moving a movable cover of a thrust reverser, comprising: an actuator including a first element (3) and a second element (4) mounted movable in translation relative to the first element, one of the first element and the second element being a screw, and the other being a nut configured to cooperate with the screw, such that rotation of the first element (3) relative to the second element (4) brings about translation of the second element (4) relative to the first element (3), and a locking device (17) including a locking piece (18) movable in rotation between a locked position wherein the locking piece (18) prevents rotation of the first element (3) and an unlocked position wherein the locking piece (18) allows rotation of the first element (3), wherein the locking device (17) includes a tooth (20, 21) mounted so as to rotate together with the first element (3), and the locking piece (18) includes a latch (47) including a locking portion (48) having a convex portion (50) and a plane or substantially concave portion (51), the convex portion (50) being configured to interfere with the tooth (20, 21) when the convex portion (50) is facing the tooth (20, 21) and the plane or substantially concave portion (51) is facing away from the tooth (20, 21) to prevent rotation of the first element (3), and the plane or substantially concave portion (51) being configured to allow rotation of the first element (3) when the plane or substantially concave portion (51) is facing the tooth (20, 21) and the convex portion (50) is facing away from the tooth (20, 21), wherein the plane or substantially concave portion (51) of the latch (47) is complementary in shape to the surface of the tooth (20, 21) which it is configured to face, wherein the tooth (20, 21) is asymmetrical so that, in the locked position, the locking piece (25) prevents rotation of the first element (3) in a first direction (A) and allows rotation of the first element (3) in a second direction (B), opposite to the first direction, wherein the locking portion (48) exhibits a semi-circular shape.

2. The actuating device according to claim 1, wherein the locking piece (18) is configured, in the locked position, to come into engagement with the tooth (20, 21) to prevent rotation of the first element (3).

3. The device according to claim 1, comprising an unlocking device (23) including an unlocking piece (25) movable in rotation between an active position wherein the unlocking piece (25) urges the locking piece (18) toward the unlocked position and a passive position wherein the unlocking piece (25) allows the locking piece (18) to return to the locked position, and a drive member (24) configured to drive the unlocking piece (25) in rotation in order for the unlocking piece (25) to move the locking piece (18) toward the unlocked position.

4. The device according to claim 3, wherein the locking piece (18) is capable of meshing with the unlocking piece (25) so that rotation of the unlocking piece (25) controls rotation of the locking piece (18).

5. The device according to claim 3, wherein the drive member (24) includes a rotating electromagnet (31).

6. The device according to claim 3, wherein the unlocking device (23) includes a return spring (32) configured to urge the unlocking piece (25) into the passive position.

7. The device according to claim 3, wherein the unlocking device (23) includes a stop (35) and a retainer (34) rotationally fixed to the unlocking piece (25) and movable in translation relative to the unlocking piece (25) between a retaining position wherein rotation of the retainer (34) is limited by the stop (35) and a release position wherein the retainer (34) is free in rotation.

8. The device according to claim 7, comprising a return member (41) adapted for urging the retainer (34) into the retaining position.

9. The device according to claim 7, comprising a rod (40) movable in translation relative to the first element (3) and configured to be urged by the second element (4) so as to move the retainer (34) into the release position.

10. The device according to claim 9, wherein the mobile rod (40) extends at least partially inside the first element (3).

11. The device according to claim 7, further including a manual unlocking device (54) for driving the retainer (34) in rotation so as to bring the unlocking piece (25) into the active position without activating the drive member (24).

12. The device according to claim 1, wherein the first element (3) is the screw and the second element (4) is the nut.

13. The device according to claim 1, wherein the tooth (20, 21) comprising a top surface and a flank surface, the flank surface extending from the top surface to connect the top surface to the locking device (17), the convex portion being configured to interfere with the flank surface of the tooth (20, 21) when the convex portion (50) is facing the tooth (20, 21) and the plane or substantially concave portion (51) is facing away from the tooth (20, 21) to prevent rotation of the first element (3), and the plane or substantially concave portion (51) being configured to allow rotation of the first element (3) when the plane or substantially concave portion (51) is facing the top surface of the tooth (20, 21) and the convex portion (50) is facing away from the tooth (20, 21), wherein the plane or substantially concave portion (51) of the latch (47) is complementary in shape to the top surface of the tooth (20, 21).

Description

PRESENTATION OF THE DRAWINGS

(1) Still more features and advantages will appear from the description that follows, which is purely illustrative and not limiting, and must be read with reference to the appended figures of which:

(2) FIG. 1 shows schematically, in longitudinal section, a device conforming to a first embodiment of the invention,

(3) FIG. 2 shows schematically, in perspective, a portion of the device of FIG. 1,

(4) FIG. 3 shows schematically, in rear view, the locking device of the device of FIG. 1,

(5) FIG. 4 shows schematically, in rear view, the unlocking device of the device of FIG. 1,

(6) FIG. 5 is a detail view showing schematically the shape of a locking piece,

(7) FIGS. 6A to 12C show schematically steps in the operation of the device conforming to the first embodiment,

(8) FIG. 13 shows schematically, in perspective, a portion of the actuating device conforming to a second embodiment of the invention,

(9) FIGS. 14A and 14B shows schematically in rear view the locking device of the device of FIG. 1, respectively in the unlocked and in the locked position,

(10) FIGS. 15A and 15B show schematically in cross section the unlocking device of the device of FIG. 1, respectively in the active and in the passive position.

DETAILED DESCRIPTION OF AN EMBODIMENT

(11) In FIG. 1, the device 1 shown includes a housing 2, a screw 3 extending from the housing 2 and a nut 4.

(12) The screw 3 has a body 10 with a generally cylindrical shape and is mounted in rotation relative to the housing 2 of the device about a rotation axis X corresponding to the longitudinal axis of the screw 3 and also corresponding to a deployment axis of the actuator.

(13) The screw 3 includes a first end 5 (or input end), designed to receive a driving torque, and a second end 6 (or free end) extending some distance from the first end 5. The actuator 1 includes a conical input wheel 7 mounted in a fixed manner with the screw 3, at the first end 5 of the screw. The conical input wheel 7 meshes with a meshing portion 8 of a drive shaft 9, so as to transmit a rotary motion of the drive shaft 9 to the screw 3.

(14) The nut 4 extends around the body 10 of the screw 3 and is designed to be fixed to an actuator tube 55 having an end 56 connected to a mobile component of the thrust reverser (a movable cover for example) through a ball joint connection 57 with anti-rotation stops.

(15) The nut 4 is mounted movable in translation relative to the screw 3 along the longitudinal axis X of the screw 3 to move the actuator tube between two extreme positions corresponding respectively to a retracted configuration and a deployed configuration of the actuator.

(16) The body 10 of the screw has a cylindrical outer surface 11 wherein is formed a helical groove 12. The nut 4 has an inner cylindrical surface 13 wherein is formed a helical groove 14. The screw 3 and the nut 4 cooperate through the helical grooves 12 and 14 wherein are accommodated balls 15 such that rotation of the screw 3 relative to the housing 2 brings about translation of the nut 4 relative to the screw 3 in the X direction.

(17) The device 1 also includes a drive shaft 9 having a first end 15 and a second end 16. The first end 15 is shaped so as to be connected to a first motor shaft of a thrust reverser or flexible shaft 58, the first motor shaft being connected to a drive motor positioned remotely from the actuating device. The second end 16 includes a conical wheel 8 arranged to mesh with the conical input wheel 7 of the screw 3 so as to drive the screw 3 in rotation.

(18) When the motor is activated, rotation of the screw 3 concomitantly drives translation of the nut 4 between a first extreme position (corresponding to a retracted position of the device) wherein the mobile component of the thrust reverser is retracted, and a second extreme position (corresponding to a deployed position of the device) wherein the mobile component of the thrust reverser is deployed, thus making it possible to deflect the air flow toward the front of the nacelle.

(19) The device 1 also includes a locking device 17 visible in FIG. 3 for locking the screw 3 in rotation when the actuator is in the retracted configuration, and thus avoiding unwanted deployment of the actuator, particularly in the flight phase.

(20) The locking device 17 includes a first locking piece 18 in the form of a pawl 46 mounted in rotation relative to the housing 2, and a second locking piece 19 having two teeth 20 and 21, the second locking piece 19 being mounted in a fixed manner to the screw 3. The pawl 46 is movable in rotation between a locked position (illustrated in FIG. 3) wherein the pawl 46 comes into engagement with one of the teeth 21, thus preventing rotation of the screw 3, and an unlocked position (illustrated for example in FIG. 7) wherein the pawl 46 is separated from the tooth 21, thus allowing rotation of the screw 3.

(21) The locking device 17 also includes a return spring 22 (such as a torsion spring) capable of driving the pawl 46 in rotation into the locked position to hold the pawl 46 in engagement with the tooth 21.

(22) Moreover, the device 1 includes an unlocking device 23 including a drive member 24 and an unlocking piece 25.

(23) The unlocking piece 25 is mounted in rotation relative to the housing 2 through a ball bearing 26 mounted between the housing 2 and the unlocking piece 25. The unlocking piece 25 is movable in rotation relative to the housing 2 about an axis of rotation which is the axis of rotation X of the screw 3, between an active position wherein the unlocking piece 25 drives the locking piece 18 into the unlocked position and a passive position wherein the unlocking piece 25 allows return of the locking piece 18 into the locked position.

(24) The unlocking piece 25 has a first small-diameter cylindrical portion 27 and a second large-diameter cylindrical portion 28.

(25) The unlocking piece 25 also includes a pin 29 visible in FIG. 3, positioned on the edge of the large-diameter cylindrical portion 28. The pin 29 is capable of driving the pawl 46 by causing it to pivot into the unlocked position when the unlocking piece 25 is driven in rotation in a first direction (shown in FIG. 2 by arrow A).

(26) Moreover, the unlocking piece 25 includes a roller 30 carried by the unlocking piece 25, also positioned on the edge of the large-diameter portion 28. The roller 30 is capable of pressing the pawl 46 to hold the pawl 46 in engagement with the tooth 21 when the pawl 46 is in the locked position and the unlocking piece 25 is in the passive position.

(27) The drive member 24 includes an electromagnet 31 positioned around the small-diameter portion 27 of the unlocking piece 25. When it is activated, the electromagnet 31 drives in rotation the unlocking piece 25 in a first direction of rotation (arrow A) into the active position in order to unlock the pawl 46.

(28) The unlocking device 23 further includes a return spring 32 capable of driving the unlocking piece 25 in another rotation direction (shown by arrow B), opposite to the first rotation direction into the passive position, so as to return the pawl 46 to the locked position when the electromagnet 24 is not activated.

(29) Moreover, the actuating device 1 includes a retaining device 33 allowing the pawl 46 to be held in the unlocked position as long as the actuator is not in the retracted configuration, even when the electromagnet 24 is not activated.

(30) The retaining device 33 includes a retainer piece 34 and a stop 35 capable of cooperating with the retainer piece 34 to selectively prevent or allow rotation of the unlocking piece 25.

(31) The retainer piece 34 includes a pusher 36 extending inside the unlocking piece 25 in the X direction, and a retaining finger 37 fixed to one end of the pusher 36 and extending in a radial direction relative to the pusher 36. More precisely, the pusher 36 extends inside the small-diameter portion 27 of the unlocking piece 25. The pusher 36 is mounted in a rotationally fixed manner to the unlocking piece 25, but is mobile in translation relative to the unlocking piece 25, in the X direction. To this end, the outer surface 38 of the pusher 36 and the inner surface 39 of the unlocking piece 25 are equipped with longitudinal grooves, the grooves of the rod 38 being capable of cooperating with the grooves of the unlocking piece 25 to allow translation of the rod 38 relative to the unlocking piece 25 while still preventing rotation of the pusher 36 relative to the unlocking piece 25.

(32) The retainer 34 is movable in translation relative to the unlocking piece 25 between a retaining position (illustrated for example in FIG. 12A) wherein rotation of the retainer 34 is limited by the stop 35, and a release position (illustrated for example in FIG. 1) wherein the retainer 34 is out of reach of the stop 35 and is consequently free in rotation.

(33) The actuating device 1 also includes a rod 40 movable in translation relative to the screw 3, the mobile rod 40 extending at least partially inside the screw 3. The mobile rod 40 is capable of being driven in translation by the nut 4 when the nut 4 reaches the first extreme position corresponding to the retracted configuration of the device 1.

(34) The retainer 34 is capable of being driven by the mobile rod 40 to move the retainer 34 in a first direction (shown by arrow C in FIG. 1) into the release position.

(35) Moreover, the retaining device 33 includes a return spring 41 capable of driving the retainer 34 in a second direction (shown by arrow D), opposite to the first direction, to return the retainer 34 to the retaining position when the mobile rod 40 is no longer driving the retainer 34.

(36) The stop 35 is fixed to the housing 2 and includes a pin 42 protruding from the housing 2 in a direction substantially parallel to the X direction. The pin 42 is capable of cooperating with the finger 37 to prevent rotation of the retainer 34 (and consequently of the unlocking piece 25) relative to the housing 2. More precisely, when the retainer 34 is in the retaining position, the finger 37 comes into radial abutment against the pin 42 under the influence of the return spring 32, the pin 42 preventing rotation of the retainer 34.

(37) As can be seen in FIG. 4, the actuating device 1 also includes a manual unlocking device 54 for driving the retainer 34 in rotation, so as to bring the unlocking piece into the active position, in the case of assembly or maintenance operations on the actuating device. More precisely, the manual unlocking device 54 includes a pusher which can be moved manually to drive the finger 37 to cause the retainer 34, and consequently the unlocking piece 25, to pivot into the active position.

(38) FIG. 5 is a detail view showing schematically the shape of the pawl 46.

(39) As illustrated in FIG. 5, the pawl 46 exhibits a second hollow portion 45 capable of coming into contact with the unlocking pin 29 when the unlocking piece 25 drives the pawl 46 into the unlocked position. The shape of the second hollow portion 45 makes it possible to reduce the friction force due to the pawl 46 resting on the pin 29 at the end of the unlocking process and during retention of the pawl 46 in the unlocked position.

(40) FIGS. 7A to 12C show schematically some operating steps of the actuating device 1.

(41) The actuating device is initially in the retracted configuration (FIG. 6A), the nut 4 being in its first extreme position.

(42) As shown in FIG. 6B, the pawl 46 is in the locked position. The free end 43 of the pawl is in abutment against the tooth 21, which prevents any rotation of the screw 3. Moreover, the roller 30 retains the pawl 46 in the locked position. In this configuration, deployment of the actuating device 1 is not possible.

(43) Moreover, as illustrated in FIGS. 6A and 6C, the retainer 34 is in the release position, the finger 37 of the retainer being out of reach of the stop 35.

(44) When the pilot commands the deployment of the thrust reverser, a control system triggers power supply to the electromagnet 31 (FIG. 7A). The electromagnet 31 then applies a torque to the unlocking piece 25, which has the effect of causing the unlocking piece 25 to rotate about the X axis, in the first direction indicated by arrow A (FIGS. 7B and 7C).

(45) Rotation of the unlocking piece 25 has the effect, initially, of disengaging the roller 30 from the pawl 46 (FIG. 9B) and simultaneously causing the finger 37 to pivot.

(46) While the unlocking piece 25 is driven in rotation by the electromagnet 31 (FIG. 8A), the pin 29, in a second step, drives the pawl 46 (FIG. 8B) to separate the pawl 46 from the tooth 21. More precisely, the pin 29 drives the pawl 46 once the roller 30 is no longer in contact with the pawl 46. Moreover, the finger 37 pivots (FIG. 8C) and passes beyond the stop 35.

(47) Once the pawl 46 is in the unlocked position (FIGS. 9A and 9B), the actuating device 1 can be deployed. In fact, the pawl 46 allows rotation of the screw 3. The screw 3 is driven in rotation such that the nut 4 translates along the screw 3 in the X direction while moving away from the first extreme position. In moving away from the first extreme position, the nut 4 ceases to drive the mobile rod 40 and consequently the retainer 34. The retainer 34 is moved in translation along the X axis in the second direction D under the influence of the return spring 41. This has the effect that the finger 37 positions itself behind the stop 35 (FIGS. 9A and 9C), the stop preventing rotation of the retainer 34 (and consequently of the unlocking piece 25) in the second direction (arrow B).

(48) From this moment on, the electromagnet 31 can be deactivated, with the pawl 46 returning to the locked position. Indeed, the retainer 34 holds the unlocking piece 25 in the active position, that is a position wherein the unlocking piece 25 holds the pawl 46 in the unlocked position.

(49) This has as a consequence that the actuating device 1 cannot be locked so long as the nut 4 has not returned to the first extreme position, that is as long as the actuating device has not returned to the retracted configuration.

(50) When the thrust reverser is retracted, the screw 3 is driven in rotation such that the nut 4 translates along the screw 3 in the X direction toward the first extreme position. When approaching the first extreme position, the nut 4 drives the mobile rod 40 and consequently the retainer 34. The retainer 34 is moved in translation along the X axis in the first direction C (FIG. 10A) under the influence of the thrust of the rod 40. This has the effect of moving the finger 37 out of reach of the stop 35.

(51) Once the finger 37 is out of reach of the stop 35 (FIGS. 11A and 9C), the stop 35 no longer prevents rotation of the retainer 34 (and consequently of the unlocking piece 25). The retainer 34 (and consequently the unlocking piece 25) is driven in rotation in the second direction (arrow B) under the influence of the return spring 32 (FIG. 11B). The unlocking piece 25 releases the pawl 46 which pivots into the locked position under the influence of the return spring 22.

(52) Rotation of the unlocking piece 25 also has the effect of returning the roller 30 into contact with the pawl 46 (FIG. 12B) and of simultaneously causing the finger 37 to pivot. The free end of the pawl 46 comes into abutment against the tooth 21 and the roller 30 supports the pawl 46 to hold the pawl 46 in engagement with the tooth 21.

(53) Thus, complete retraction of the actuating device brings about an automatic return of the locking device into the locked position. Once the locking device is in the locked position, the locking device can no longer be unlocked unless the pilot again commands the deployment of the thrust reverser, which triggers activation of the electromagnet.

(54) FIG. 13 shows schematically an actuating device 1 conforming to a second embodiment of the invention.

(55) The actuating device 1 according to the second embodiment is identical to the device of the first embodiment, with the exception of the fact that the locking piece 18 is a cylindrical latch 47 mounted in rotation relative to the housing 2 about an axis X parallel to the X axis.

(56) The cylindrical latch 47 includes, on the one hand, locking portion 48, and on the other hand a drive portion 49.

(57) As illustrated in FIGS. 14A and 14B, the locking portion 48 exhibits a half-moon shape. More precisely, the locking portion 48 includes a convex portion 50 for engagement and a concave (or substantially flat) portion 51 for disengagement, capable of being selectively positioned facing the tooth 21 when the latch 47 is driven in rotation.

(58) When the latch 47 is in the unlocked position (FIG. 14A), the concave portion 51 is positioned facing the tooth 21 so as to allow rotation of the second locking piece 19 (and consequently of the screw). When the latch 47 is in the locked position (FIG. 14B), the convex portion 50 is positioned facing the tooth 21 so as to interfere with the tooth 21 and thus prevent rotation of the screw 3.

(59) As illustrated in FIGS. 15A and 15B, the drive portion 49 includes a toothed sector 52. The unlocking piece 25 also includes a toothed sector 53 arranged so as to mesh with the toothed sector 52 of the latch 47. Thus, rotation of the latch 47 is controlled by rotation of the unlocking piece 25.

(60) Rotation of the unlocking piece 25 in the first direction of rotation (arrow A) has the consequence of causing the latch 47 to pivot into the unlocked position (illustrated in FIG. 15B).

(61) Conversely, rotation of the unlocking piece 25 in the second direction (arrow B), opposite to the first direction, has the effect of causing the latch 47 to pivot into the locked position (illustrated in FIG. 15A).

(62) The operation of the actuating device 1 according to the second embodiment is identical to the operation of the actuating device 1 according to the first embodiment.