JP5802375B2 - Aircraft actuator - Google Patents

Description

  The present invention relates to an aircraft electric actuator, and more particularly to an aircraft electric actuator suitable for opening and closing various doors provided in an aircraft.

  In the technical field related to actuators for aircraft, research and development of EMA (Electro Mechanical Actuator) and EHA (Electro Hydrostatic Actuator) has become a global trend in order to reduce the weight of the aircraft by eliminating the hydraulic system. .

  Here, as a technique regarding EMA, for example, there is one described in Patent Document 1. In the electric actuator (EMA) described in Patent Document 1, two electric motors are arranged in one actuator. The two electric motors are disposed on both sides of the actuator portion via power transmission members. When one electric motor fails, the actuator can be operated by the other electric motor.

US Patent Application Publication No. 2007/0051847

  However, in the electric actuator described in Patent Document 1, as compared with an electric actuator using one electric motor, one electric motor and one set of power transmission member such as a gear connecting the electric motor and the actuator. The weight increases. Moreover, it will become a big electric actuator for one electric motor and one set of power transmission members.

  On the other hand, when an electric actuator (EMA) is used for a door such as a cargo compartment, when the electric motor fails and the door cannot be opened and closed automatically (electrically), for example, the door is opened by manually operating the actuator. Even if the door is opened and closed, there is no particular problem on the flight as long as the door can be completely closed. However, simply adding a manual operation mechanism to an existing EMA with an electric motor is not preferable for the safety of actuator operation.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an electric actuator (EMA) for an aircraft including a manual operation mechanism that can be manually operated safely. is there.

  The present invention relates to an electric actuator for an aircraft, and includes an electric motor, a speed reduction mechanism attached to an output side of the electric motor, and a screw shaft attached to an output side of the speed reduction mechanism via a power transmission member. A nut screwed to the screw shaft, a rod that expands and contracts via the nut by rotation of the screw shaft, a rod manual operation mechanism that meshes with the speed reduction mechanism and manually expands and contracts the rod; The rod manual operation mechanism includes a manual power transmission member meshing with the speed reduction mechanism, and one end portion at an end of the manual power transmission member so as to be movable relative to the manual power transmission member in the axial direction. Are arranged in a gap between the plunger that is engaged and a manual operation force is applied to the other end, a casing that accommodates the rod manual operation mechanism, and the plunger. A spring that biases the plunger in a direction away from the power transmission member, the plunger being serrated to the inner wall of the casing, and applying a manual operation force to the other end of the plunger. In addition, the electric actuator for an aircraft is characterized in that the plunger is rotated by releasing the serration coupling by pushing the plunger inward of the casing against the biasing force of the spring.

  According to this configuration, the plunger does not rotate unless the plunger is pushed inward of the casing. That is, the plunger does not rotate carelessly. Thereby, the operator can operate the electric actuator manually and safely.

  Further, in the present invention, the manual power transmission member includes a manual power transmission gear meshing with the speed reduction mechanism, a rod-shaped member disposed inside the manual power transmission gear and engaged with the plunger, and the manual power transmission gear. A clutch mechanism provided between the bar-shaped member and frictionally engaging the manual power transmission gear and the bar-shaped member, and when the rotational torque applied to the plunger exceeds a predetermined torque, the manual power It is preferable that the engagement between the transmission gear and the rod-shaped member is released by the clutch mechanism.

  According to this configuration, when the manual operation force is too large, the transmission of the manual operation force can be cut by the clutch mechanism, and damage to the speed reduction mechanism, the screw shaft, and the like can be prevented. That is, it is possible to prevent parts constituting the electric actuator from being damaged by manual operation. This effect leads to the effect that the electric actuator can be safely operated manually.

  Further, in the present invention, the electric motor is a motor incorporating a brake, and the speed reduction mechanism includes a sun gear, a plurality of planetary gears, a planetary carrier, and a ring gear arranged outside the plurality of planetary gears. The ring gear has a plurality of teeth that engage with the manual power transmission gear on the outer periphery of the end opposite to the side on which the planetary gear is disposed. When expanding and contracting the rod, the ring gear meshing with the manual power transmission gear is fixed by the serration coupling, so that the screw shaft is rotated by the rotation of the sun gear, and the rod is manually expanded and contracted The sun gear is fixed by the brake, the serration coupling is released, and the ring gear is rotated by a manual operation force. It is, it is preferable that the screw shaft is rotated to be.

  According to this configuration, a part such as a gear between the electric motor and the screw shaft and a part such as a gear between the rod manual operation mechanism and the screw shaft can be partially shared. As a result, a compact electric actuator can be obtained.

  According to the present invention, the operator of the electric actuator can safely operate the electric actuator manually.

It is a sectional side view showing the electric actuator for aircrafts concerning one embodiment of the present invention. It is the A section enlarged view of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The electric actuator for aircraft described below is assumed to be an electric actuator (EMA) for opening and closing the door of the cargo compartment of the aircraft, but the electric actuator for aircraft of the present invention is used to get on and off a person installed in the aircraft. It can also be used as an electric actuator for opening and closing a door for making it move, and it can also be used as an electric actuator for operating a door that opens and closes to raise and lower an aircraft leg. That is, the electric actuator for aircraft of the present invention can be used as an electric actuator for opening and closing various doors provided in the aircraft.

(Configuration of electric actuator for aircraft)
FIG. 1 is a side sectional view showing an aircraft electric actuator (hereinafter referred to as “electric actuator”) according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion A thereof.

  As shown in FIGS. 1 and 2, the electric actuator 1 includes a rod 7 disposed in the cylinder 13, and an electric motor 2 and a rod manual serving as a drive source for expanding and contracting (linearly moving) the rod 7. An operation mechanism 8 and a controller 9 for controlling the electric motor 2 are provided.

(Cylinder structure)
A rod 7, a nut 6, and a screw shaft 5 are disposed in the cylindrical cylinder 13. The rod 7 has a hollow cylindrical shape, and an attachment portion 7b to which a door-side member is attached is provided at one end thereof. At the other end of the rod 7, a ring-shaped protrusion 7 a that engages with the nut 6 is provided. The mounting portion 7b always protrudes from the cylinder 13. The protruding portion 7 a has a protruding portion 7 a 1 on the inner side, and is engaged with the recessed portion 6 a of the nut 6. That is, a recess 6a is provided on the outer periphery of the end portion of the nut 6, and the rod 7 and the nut 6 are contracted (retracted) when the rod 7 extends (advances) in the recess 6a. Maintain the engaged state.

  A screw shaft 5 is disposed inside the rod 7. The screw shaft 5 has a hollow cylindrical shape, and is threaded on the outer periphery from one end to the other end. The nut 6 is screwed onto the screw shaft 5. For example, a ball screw is used for screwing between the screw shaft 5 and the nut 6. A position sensor 11 and a position sensor rod 10 are arranged inside the screw shaft 5. The position sensor rod 10 is coaxial with the rod 7 and fixed to the rod 7. The position sensor 11 is a sensor for detecting the expansion / contraction position of the rod 7.

  Note that an angle detector such as an encoder, a resolver, or a hall sensor may be incorporated in the electric motor 2 and the expansion / contraction position of the rod 7 may be detected by the detector.

(Electric motor and its controller)
The electric motor 2 is a motor with a built-in electromagnetic brake 2a. When the electromagnetic brake 2a is excited, the brake is released, and the output shaft 2b of the electric motor 2 can rotate. Note that when the electric motor 2 is not supplied with electric power or the like, the electromagnetic brake 2a cannot be excited, so that the brake is applied, that is, the output shaft 2b of the electric motor 2 is not rotatable. As the electric motor 2, for example, a brushless DC motor can be cited, but a motor of another structure / type may be used.

  The controller 9 is a motor control means for controlling the electric motor 2. External signals, signals from the position sensor 11 and the like are input to the controller 9, and the controller 9 controls the rotation of the electric motor 2 based on these input signals. The controller 9 is attached to the side surface of the cylinder 13.

(Power transmission mechanism)
A power transmission mechanism between the electric motor 2 and the screw shaft 5 will be described. This power transmission mechanism includes a first spur gear mechanism 15, a planetary gear mechanism 3, a power transmission member 4, and a second spur gear mechanism 22 in order from the electric motor 2 side. That is, the screw shaft 5 is attached to the output side of the electric motor 2 via the first spur gear mechanism 15, the planetary gear mechanism 3, the power transmission member 4, and the second spur gear mechanism 22. The first spur gear mechanism 15, the planetary gear mechanism 3, the power transmission member 4, and the second spur gear mechanism 22 are housed in the casing 12 together with the rod manual operation mechanism 8 described later. A mounting portion 14 for mounting on the airframe is provided on the outer surface of the casing 12 opposite to the mounting portion 7 b provided on the rod 7. The casing 12 is attached to the side surface of the cylinder 13 opposite to the controller 9.

  Here, the spur gear provided on the outer periphery of the tip end of the output shaft 2b of the electric motor 2 and the spur gear 15a on the input side of the first spur gear mechanism 15 are meshed, and the output shaft portion of the first spur gear mechanism 15 is engaged. A sun gear 18 constituting the planetary gear mechanism 3 is fixed to 15b.

  The planetary gear mechanism 3 is a speed reduction mechanism attached to the output side of the electric motor 2, and includes a sun gear 18, a plurality of planetary gears 19, a planetary carrier 21 that rotates the planetary gears 19, and a ring gear 20. It has. The planet carrier 21 is a part formed in a bifurcated cross section (Y-shaped cross section). The ring gear 20 is disposed outside the plurality of planetary gears 19. A flat tooth 20a (a plurality of teeth) is provided on the inner surface on one end side of the ring gear 20, and a flat tooth 20b (a plurality of teeth) is provided on the outer surface on the other end side. The spur teeth 20a mesh with the planetary gear 19, and the spur teeth 20b mesh with a manual power transmission gear 29 described later. The planetary gear mechanism 3 is not necessarily used. For example, a spur gear mechanism in which a plurality of spur gears are combined may be used as the speed reduction mechanism.

  The power transmission member 4 is a coupling (joint) that connects the output shaft portion 21 a of the planetary carrier 21 and the input shaft portion 23 a of the spur gear 23 that constitutes the second spur gear mechanism 22. As the power transmission member 4, it is preferable to use a known coupling (joint) called “No-back”. A coupling (joint) called “No-back” is a joint having a structure in which torque from the output side (rod 7 side) does not reach the input side.

  The second spur gear mechanism 22 includes a spur gear 23 having an input shaft portion 23 a and a spur gear 24 that meshes with the spur gear 23. The spur gear 24 is fixed to the outer periphery of the screw shaft 5. Thrust bearings 25 are disposed on both sides of the spur gear 24. The thrust bearing 25 is a bearing for receiving an axial load acting on the spur gear 24 via the screw shaft 5.

(Rod manual operation mechanism)
The rod manual operation mechanism 8 is for manually extending and retracting the rod 7, and is accommodated in the casing 12 a portion of the casing 12. This rod manual operation mechanism 8 is movable relative to the manual power transmission member 26 meshing with the ring gear 20 constituting the planetary gear mechanism 3 and the rod-shaped member 30 constituting the manual power transmission member 26 in the axial direction thereof. And a plunger 27 formed on the surface.

  The plunger 27 is a cylindrical part having a stepped cavity 27c. The inner surface on one end side of the plunger 27 is splined, and the outer surface on the other end side is serrated. That is, the plunger 27 is spline-coupled 27a to the rod-shaped member 30 and serrated to the inner wall of the casing 12a. The serration coupling refers to a coupling for fixation (for rotation fixation) that is movable in the axial direction.

  Here, a coil spring 28 is disposed in the gap between the casing 12 a and the plunger 27. The coil spring 28 is a spring for biasing the plunger 27 in a direction away from the rod-shaped member 30 constituting the manual power transmission member 26. The type of spring is not limited to a coil spring.

  A proximity sensor 37 is disposed on the inner surface of the casing 12a that accommodates the plunger 27, and a detection target component 38 of the proximity sensor 37 is attached to the end of the plunger 27 on the splined side. Yes. The proximity sensor 37 is a sensor for detecting whether or not the plunger 27 is pushed inwardly of the casing 12a (the bar-shaped member 30 side).

  Next, the manual power transmission member 26 includes a rod-shaped member 30 that is spline-coupled to the plunger 27, a manual power transmission gear 29 disposed outside the rod-shaped member 30, and a space between the rod-shaped member 30 and the manual power transmission gear 29. And a clutch mechanism 31 provided in the vehicle.

  The manual power transmission gear 29 is disposed on one end side of the rod-shaped member 30. The other end side of the rod-shaped member 30 is spline-processed, and the spline-processed portion 30 a can enter the hollow portion 27 c of the plunger 27.

  The manual power transmission gear 29 is a spur gear and is meshed with the ring gear 20 constituting the planetary gear mechanism 3.

  The clutch mechanism 31 is for frictionally engaging the rod-shaped member 30 and the manual power transmission gear 29. The clutch mechanism 31 includes a roller 36, a ring 35, a disc spring 34, a ring 33, and a nut 32, which are ring-shaped parts.

  The rollers 36 are disposed on both sides of the inner portion of the manual power transmission gear 29. Two rings 35 are arranged outside the roller 36 so as to sandwich the two rollers 36, and are fixed to the rod-shaped member 30 with a key. Two disc springs 34 are arranged outside the ring 35 so as to sandwich the two rings 35 therebetween. Further, a ring 33 is disposed on the outer side, and a nut 32 is screwed into the end of the rod-shaped member 30.

  By adjusting the screwing force of the nut 32, the frictional engagement force between the ring 35 and the roller 36 and between the roller 36 and the inner portion of the manual power transmission gear 29, that is, the rod-shaped member 30 and the manual power transmission gear. The frictional engagement force with 29 can be adjusted.

(Electric actuator operation)
Next, the expansion and contraction operation of the rod 7 will be described separately for the electric case and the manual case. Since the operation of extending the rod 7 and the operation of contracting the rod 7 are the same operations except that the operation direction is opposite, the operation when the rod 7 is extended will be described here.

(Electric case)
The electric motor 2 is rotated by a command from the controller 9. At this time, since the plunger 27 is urged in the direction away from the rod-shaped member 30 by the urging force of the coil spring 28, the plunger 27 is stopped without rotating through the serration coupling 27b on the inner wall of the casing 12a. Further, the rod-shaped member 30 is similarly stopped because it is splined 27 a to the plunger 27, and the manual power transmission gear 29 that is frictionally engaged with the rod-shaped member 30 via the clutch mechanism 31 is also stopped. Yes. Therefore, the ring gear 20 that meshes with the manual power transmission gear 29 is also stopped (in a fixed state).

  When the electric motor 2 rotates, the output torque of the electric motor 2 is transmitted to the planetary gear mechanism 3 via the first spur gear mechanism 15. When the ring gear 20 is in a fixed state, the planetary gear 19 revolves while rotating by the rotation of the sun gear 18. As the planetary gear 19 revolves, the planetary carrier 21 rotates, and the output torque is transmitted to the screw shaft 5 via the power transmission member 4 and the second spur gear mechanism 22. As the screw shaft 5 rotates, the nut 6 moves in the forward direction, and when the nut 6 pushes the rod 7, the rod 7 extends. When the rod 7 extends to a predetermined position (the position sensor 11 detects the position of the rod 7), the electric motor 2 is stopped by the command from the controller 9 and the electromagnetic brake 2a is operated to stop and fix the rod 7. To do.

(Manual)
The other end 27d of the plunger 27 is pushed to push the plunger 27 inward of the casing 12a against the urging force of the coil spring 28. Thereby, the serration coupling 27b of the plunger 27 is disengaged, and the plunger 27 can be rotated. At this time, the detection target component 38 attached to the end of the plunger 27 moves in a direction away from the proximity sensor 37. In response to the signal from the proximity sensor 37, the controller 9 issues a signal for releasing the electromagnetic brake 2a (for applying the brake). As a result, the output shaft 2b of the electric motor 2 becomes non-rotatable. As a result, the first spur gear mechanism 15 also cannot rotate and the sun gear 18 is fixed.

  When the electromagnetic brake 2a is de-energized before the rod 7 is extended, and the electromagnetic brake 2a is used as a stop brake, the signal from the proximity sensor 37 is not necessary. In addition, when the electric motor 2 is not supplied with electric power (when the electric system is faulty), the electromagnetic brake 2a cannot be excited, so the brake is applied. The signal from 37 becomes unnecessary.

  Thereafter, the plunger 27 is manually rotated. The plunger 27 may be rotated using an air drill or the like. The manual rotational force applied to the plunger 27 is transmitted to the rod-shaped member 30, the clutch mechanism 31, and the manual power transmission gear 29, and the ring gear 20 that meshes with the manual power transmission gear 29 rotates. Since the sun gear 18 is fixed by the electromagnetic brake 2a, the planetary gear 19 revolves while rotating as the ring gear 20 rotates. As the planetary gear 19 revolves, the planetary carrier 21 rotates, and the manual rotational force is transmitted to the screw shaft 5 via the power transmission member 4 and the second spur gear mechanism 22. As the screw shaft 5 rotates, the nut 6 moves in the forward direction, and when the nut 6 pushes the rod 7, the rod 7 extends.

  Here, the clutch mechanism 31 is configured so that the frictional engagement between the rod-shaped member 30 and the manual power transmission gear 29 is released when the manual rotational force (rotational torque) applied to the plunger 27 exceeds a predetermined torque value. Is set. By setting the clutch mechanism 31 in this way, when the manual operating force is too large, the transmission of the manual operating force can be cut by the clutch mechanism 31, and the planetary gear mechanism 3 and the second spur gear Damage to the mechanism 22, the screw shaft 5, etc. can be prevented. That is, it is possible to prevent parts constituting the electric actuator 1 from being damaged by manual operation.

  According to the rod manual operation mechanism 8 of the electric actuator 1 according to the present embodiment, the plunger 27 rotates unless the plunger 27 is pushed inward of the casing 12a by the serration coupling 27b between the inner wall of the casing 12a and the plunger 27. There is no. That is, the plunger 27 does not rotate carelessly. As a result, the operator can manually extend and retract the rod 7 safely.

  Further, in the electric actuator 1 according to the present embodiment, the components on the output side after the planetary gear mechanism 3 can be shared between the electric operation and the manual operation. As a result, a compact electric actuator 1 can be obtained.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. .

1: Aircraft electric actuator 2: Electric motor 3: Planetary gear mechanism (deceleration mechanism)
4: Power transmission member 5: Screw shaft 6: Nut 7: Rod 8: Rod manual operation mechanism 12a, 12: Casing 26: Manual power transmission member 27: Plunger 27a: Spline coupling 27b: Serration coupling 28: Coil spring

Claims (2)

An electric actuator for an aircraft,
A planetary gear reduction mechanism attached to the output side of the electric motor incorporating the brake;
A rod that expands and contracts by the output of the planetary gear reduction mechanism;
A rod manual operation mechanism for manually expanding and contracting the rod;
With
The ring gear of the planetary gear speed reduction mechanism has teeth on its outer periphery,
The rod manual operation mechanism is provided so as to be capable of serration coupling to the casing, and has a plunger that engages with a manual power transmission gear that meshes with an outer peripheral tooth of the ring gear,
The rod manual operation mechanism includes a spring that biases the plunger in a direction in which the plunger is serrated to the casing,
When electrically extending and contracting the rod, the ring gear is fixed by the serration coupling, so that the rod expands and contracts by rotation of the sun gear of the planetary gear reduction mechanism,
When the rod is manually expanded and contracted, the sun gear is fixed by the brake, and the plunger can be rotated by removing the serration coupling by applying a manual operation force and resisting the biasing force of the spring. to, that is pre-Symbol ring gear Ri by the manual operation force is rotated, characterized in that the rod is telescopic, the electric actuator aircraft. The aircraft electric actuator according to claim 1 ,
The rod manual operation mechanism is
A rod-shaped member disposed inside the manual power transmission gear and engaged with the plunger;
A clutch mechanism provided between the manual power transmission gear and the rod-shaped member, and frictionally engaging the manual power transmission gear and the rod-shaped member;
With
When the rotational torque applied to the plunger exceeds a predetermined torque, the engagement between the manual power transmission gear and the rod-shaped member is released by the clutch mechanism.

Images