JPH02273049A - Electrically-driven actuator - Google Patents

Abstract

PURPOSE:To prevent the sticking of an actuator by a method wherein the title actuator is provided with a collet lock device, having a plurality of pawls movable axially, a lock plate, insertable into the collet lock device, and a lock releasing electrically-driven actuator for taking the lock plate out of the collet lock device. CONSTITUTION:When a pilot throws a sticking releasing switch, a lock releasing electrically-driven actuator 7 is operate. through a connector 10 to push a lock plate 11 out and release the lock of a collet lock device 6. The lock plate 11 of the collet lock device 6 is released, a pawl 6a is deflected inwardly by the external force of a piston 5 at a locking step on the inner wall of a cylinder barrel 9 and the look is released whereby an actuator unit 14 is stroked. According to this method, the sticking of the electrically-driven actuator 14 may be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric actuator applied to an actuator of a control surface actuating device and a landing gear of an aircraft.

C. Prior Art] FIG. 3 shows a typical example of a conventional electric direct-acting actuator. In FIG. 0, the normal operation of the actuator is to transfer the output of the electric motor 13 to the spur gears 10, 11, .
Spur gear12. It operates by transmitting power to the piston 4 via the ball screw 5 and pole nut 6 reduction mechanism and transmission device. In a typical actuator configuration, the mounting bracket 2 of the actuator is attached to the fixed side with a bolt, and the rod end 3 is attached to the movable side.

Since a conventional electric actuator is composed of many mechanical parts as shown in the figure, the biggest problem is that it cannot function due to mechanical fixation inside the actuator.

Causes of sticking include seizure due to poor lubrication in functional parts such as bearings, spur gears, ball screws, and pole nuts, damage to parts due to overload or lack of durability, jamming of foreign objects, and electric motors due to excessive use. The motor may be overheating, etc.

For example, in Fig. 3, if the pole nut 6 catches a foreign object attached to the ball screw 5 during normal operation and a sticking occurs between the ball screw 5 and the pole nut 6, the piston 4 becomes inoperable and cannot extend or retract. .

If the piston 4 becomes stuck while the aircraft is being steered or the landing gear is being lifted or lowered, this will result in a very dangerous situation, and it is conceivable that the aircraft will rupture.

Therefore, if a sticking occurs inside the electric actuator, the electric actuator is immediately freed and the electric actuator is overridden (0νERRIDE) by an external force (aerodynamic force or the weight of the legs), and the control surface is brought to the neutral position and the legs are It is necessary to operate it to the leg down position.

Hydraulic cylinders are commonly used in aircraft because, in addition to securing large output through hydraulic pressure, using a simple hydraulic cylinder reduces the probability of the actuator sticking.
This is because there is an advantage that the actuator can be easily overridden by a simple bypass system.

Even in the case of electric actuators, if the piston becomes inoperable due to sticking, an override function similar to that of a hydraulic cylinder is required so that the minimum necessary operations can be performed to safely fly or land the aircraft. The current situation is unresolved.

[Problems to be Solved by the Invention] The conventional electric actuator described above has the following problems to be solved.

(1) If mechanical fixation occurs inside the actuator in an electric actuator, the actuator will be mechanically held in the fixed position. Therefore, when used to operate the control surface of an aircraft, in the worst case, the control surface may be held at the maximum rudder angle position, resulting in a dangerous situation in terms of flight performance.

(2) When an electric actuator is used to lift and lower the union on the landing gear of an aircraft or to open and close the landing gear door, if the actuator becomes inoperable due to mechanical fixation inside the actuator during operation, the landing gear You will not be able to lower it.

[Means to solve the problem]

As a solution to the above problem, the present invention is provided so as to be slidable in the axial direction along the inner periphery of the cylinder barrel, and is located near the bottom of the cylinder barrel so that when the cylinder barrel bends outward, it locks onto the cylinder barrel and moves inward. A collet lock device has a plurality of claws that can be moved in the axial direction to follow the rod end when the rod is bent, and the collet lock device is provided inside the collet lock device so that it can be inserted and removed, and when the collet lock device is inserted, the claws can be removed. A lock plate that locks the cylinder barrel by pressing it in the opposite direction and releases the pawl from the cylinder barrel when released, and a lock release that releases the lock plate from the collet lock device. An object of the present invention is to provide an electric actuator characterized by comprising an electric actuator.

[For production]

Since the present invention is configured as described above, it has the following effects.

That is, the lock plate is fitted by pressing the claw of the collet locking device slidably provided along the inner circumference of the cylinder barrel outward at the bottom of the cylinder barrel, and in this state,
Electric motor and gears that operate (extend and retract) the rod end.
If the ball screw, pole nut, piston, etc. are fixed to the collet lock device, in normal operation, the cylinder barrel fixed to the driven side of the aircraft will
The rod end fixed to the driven side of the aircraft performs normal operation without any problems.

In the unlikely event that a problem occurs with the electric motor, gears, ball screw ball nand piston, etc. and the rod end becomes unable to operate, the lock plate can be removed from the collet lock device by operating the electric actuator for long release. The collet locking device, which was locked to the cylinder barrel with a claw, can now slide in the axial direction of the cylinder barrel, allowing the driven side and driven side to move freely in the direction in which the rod end should move (extension or retraction). Can be close to each other or separated from each other. That is, the problem caused by the electric actuator being stuck is eliminated.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a vertical cross-sectional view of an electric actuator incorporating a lock release device according to the present embodiment, and the configuration in which the electric actuator is normally operated is the same as that of a conventional actuator, in which the planetary gear set 2 is operated by the output of the electric motor 1. , a pole nut 3, and a ball screw 4 to operate a piston 5 of the actuator.

The difference from the conventional example, that is, the characteristic point of this embodiment is a lock release device 8 consisting of a collet lock device 6 and a small electric actuator 7 for lock release, and an override function of the electric actuator and its mechanism. That is, in order to add the lock release device 8 to the electric actuator, the functional parts of the conventional electric actuator are arranged in a straight line, and a cylinder barrel 9 is provided on the outside of the electric actuator, so that it can be used as a hydraulic cylinder type electric actuator. It is configured.

Next, the operation of the lock release device 8 will be explained. 1. During the operation of lowering the landing gear of an aircraft (not shown), the planetary gear system of the electric actuator! Assume that the piston 2 is damaged and the piston 5 is stuck in the leg-up position (the position shown in FIG. 1 where the piston 5 is retracted) and becomes inoperable.

In this case, when the pilot turns on the lock release switch, power is supplied to the lock release compact electric actuator tough via the lock release connector 10, and the lock release electric actuator 7 is activated. Then the second
As shown in the figure, the lock plate 11 is pushed out (protrudes to the right in the figure), and the lock of the collet lock device 6 is released.

That is, as will be described later, the claw 6a of the collet lock device 6 is in a state where it can be freely bent inward.

On the other hand, since the external force due to the weight of the legs is constantly applied in the direction of extending the piston 5 via the rod end 12, when the lock plate 11 of the collet lock device 6 comes off, the claw 6a of the collet lock device 6 becomes free and the piston 5 Due to the applied external force, the pawl 6a is deflected inward by the locking step on the inner diameter of the cylinder barrel 9, and the lock is released, causing the entire actuator section 14 to stroke like a hydraulic piston, as shown in FIG.

The cylinder barrel 9 is bolted to the driven side of the fuselage via a spherical bearing 13, and is connected to the driven side of the body via a rod end 12, so that the entire actuator section 14 is It is moved by the free fall of the legs (external force), and the legs can be lowered to the normal position.

FIG. 2 shows the operating state of the lock release device 8 and the overriding state of the electric actuator. If the relative motion between the actuator section 14 and the cylinder barrel 9, which is shown as a stroke in the figure, is the same as the stroke required for normal operation, the normal operation range can be covered no matter where the normal operation is stuck.

Incidentally, since the impact upon landing is absorbed by the script body, this actuator will not be shortened by the impact.

In the figure, 15 is a jack screw, 16 is a connector, 16a is an electric wire, 17 is an actuator housing, 18 to 20 are splines, and 21 is a motor housing for the electric motor l.

Since this embodiment is constructed as described above, even if it becomes stuck during operation, it can be immediately released from the stuck state by energizing the lock release electric actuator, so that the control surface of the aircraft can be adjusted to its maximum rudder. This has many advantages, such as preventing the user from being exposed to a dangerous situation due to being locked in the corner, and avoiding jamming when the legs are lowered.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects. That is, by eliminating sticking, which was the biggest problem with conventional electric actuators, it is possible to obtain an electric actuator with high reliability comparable to that of a hydraulic actuator. As a result, it has become possible to employ this electric actuator as a control surface actuator and landing gear actuator of an aircraft.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of an electric actuator according to an embodiment of the present invention, and FIG. 2 shows a state in which the electric actuator of the above embodiment is stuck and the cylinder barrel 9 is released when the long release device is activated. 3 is a longitudinal sectional view of a conventional example. 1... Electric motor, 2... Planetary gear device. 3...・Ball nut, 4...Ball screw 5...Piston 6...Choleratrotsuta device. 7...Electric actuator for lock release. 8...Lock release device 9...Cylinder barrel. 1O...Connector , 11... lock plate 12
···Rod ends. 13... Spherical bearing 14/Nen) Actuator section. Figure 3

Claims (1)

[Claims] It is provided so as to be able to slide in the axial direction along the inner circumference of the cylinder barrel, and is located near the bottom of the cylinder barrel. When it bends outward, it locks into the cylinder barrel, and when it bends inward, it follows the rod end. A collet lock device has a plurality of pawls that are movable in the axial direction, and the collet lock device is provided inside the collet lock device so that it can be inserted and removed, and in the fitted state, the pawls are pressed outward and locked to the cylinder barrel. The lock plate is provided with a lock plate that allows the claw to be released from the cylinder barrel in a detached state, and a lock release electric actuator that detaches the lock plate from the collet lock device. Characteristic electric actuator.