ACTUATOR IN A LANDING GEAR SYSTEM OF AN AIRCRAFT

Abstract

The present invention relates to an actuator in a landing gear system of an aircraft, comprising: an electric drive for driving the actuator and first drive electronics for controlling the electric drive that are connected to the drive via an electric line, with second drive electronics for controlling the electric drive that are connected to the drive via an electric line, with the first drive electronics and the second drive electronics being redundant with respect to one another.

Claims

1. Actuator (1) in a landing gear system of an aircraft, comprising: an electric drive (2) for driving the actuator (1); and first drive electronics (3) for controlling the electric drive (2) that are connected to the drive (2) via an electric line (5), and second drive electronics (4) for controlling the electric drive (2) that are connected to the drive (2) via an electric line (6), with the first drive electronics (3) and the second drive electronics (4) being redundant with respect to one another.

2. An actuator (1) in accordance with claim 1, wherein the actuator (1) is an electromechanical actuator (1) or an electrohydraulic actuator (1); and the electric drive (2) is preferably a pump (7) of a hydraulic circuit with an electrohydraulic actuator (1).

3. An actuator (1) in accordance with claim 1, wherein the first drive electronics (3) are different from or identical to the second drive electronics (4).

4. An actuator (1) in accordance with claim 1, wherein the actuator (1) only has the one electric drive (2) and/or the actuator has a decentralized hydraulic circuit.

5. An actuator (1) in accordance with claim 1, wherein the electric drive (2) is an electric motor that is connected both to the first drive electronics (3) and to the second drive electronics (4), with the first drive electronics (3) and the second drive electronics (4) preferably being connected to one another via a communications link (8).

6. An actuator (1) in accordance with claim 5, wherein the electric motor (2) is a dual winding motor whose windings are electrically independent of one another, with one of the windings preferably cooperating with the first drive electronics (3) and the other winding cooperating with the second drive electronics (4).

7. An actuator (1) in accordance with claim 6, wherein the dual winding is present on a common shaft and/or on the same rotor magnets.

8. An actuator (1) in accordance with claim 5, wherein the electric motor (2) has redundantly implemented phases, with one of the redundant phases cooperating with the first drive electronics (3) and the other one of the redundant phases cooperating with the second drive electronics (4).

9. An actuator (1) in accordance with claim 5, furthermore having a switchover unit that permits a control of the motor either by the first drive electronics (3) or by the second drive electronics (4).

10. An actuator (1) in accordance with claim 5, wherein the electric motor (2) is a 3-phase permanent magnetic synchronous motor that is preferably provided with a resolver or with a Hall effect sensor for the motor regulation.

11. An actuator (1) in accordance with claim 1, furthermore having a first motor sensor (9) for determining an operating state of the drive (2) and a second motor sensor (10) for determining an operating state of the drive (2), with the first motor sensor (9) being electrically connected to the first drive electronics (3) and the second motor sensor (10) being electrically connected to the second drive electronics (5).

12. An actuator (1) in accordance with claim 1, wherein the actuator (1) is adapted to actuate landing gear or to control a landing gear wheel.

13. An actuator (1) in accordance with claim 1, wherein the performance of the actuator (1) or of the electric drive (2) is independent of the failure of one of the two mutually redundant drive electronics (3, 4).

14. An actuator (1) in accordance with claim 1, wherein the performance of the actuator (1) or of the electric drive (2) reduces on the failure of one of the two mutually redundant drive electronics (3, 4), for example by half.

15. A landing gear system of an aircraft that comprises a plurality of actuators (1) in accordance with claim 1, wherein the first drive electronics (3) and the second drive electronics (4) for the plurality of actuators (1) of the landing gear system are arranged together in a decentralized manner at a location.

16. An actuator (1) in accordance with claim 2, wherein the first drive electronics (3) are different from or identical to the second drive electronics (4).

17. An actuator (1) in accordance with claim 16, wherein the actuator (1) only has the one electric drive (2) and/or the actuator has a decentralized hydraulic circuit.

18. An actuator (1) in accordance with claim 3, wherein the actuator (1) only has the one electric drive (2) and/or the actuator has a decentralized hydraulic circuit.

19. An actuator (1) in accordance with claim 2, wherein the actuator (1) only has the one electric drive (2) and/or the actuator has a decentralized hydraulic circuit.

20. An actuator (1) in accordance with claim 17, wherein the electric drive (2) is an electric motor that is connected both to the first drive electronics (3) and to the second drive electronics (4), with the first drive electronics (3) and the second drive electronics (4) preferably being connected to one another via a communications link (8).

Description

[0025] Further details, features and advantages of the invention will be explained with reference to the following description of the Figures. There are shown:

[0026] FIG. 1: classical actuator systems with a central hydraulic supply from the prior art;

[0027] FIG. 2: electrohydraulic actuators with complete redundancy of a decentralized pressure generation from the prior art;

[0028] FIG. 3: a schematic representation of the present invention with reference to an electrohydraulic actuator;

[0029] FIG. 4: a schematic representation of the present invention with reference to an electromechanical actuator;

[0030] FIG. 5: a schematic representation of an EHA drive for nose wheel control and landing gear actuation in accordance with the invention; and

[0031] FIG. 6: a schematic representation of an electromechanical actuator for landing gear actuation in accordance with the invention.

[0032] FIG. 1 illustrates the prior art and shows two different actuators, with left one thereof serving the control of a nose wheel and the right one serving the actuation of landing gear. The individual actuators 1 are here linked via a central hydraulic supply 11. The corresponding motor for controlling the nose wheel or for actuating the landing gear is driven by the opening or regulating of valves. The redundant design of position sensors and of the associated electronics generates two signals that differ from one another and that are conducted to the valves 12.

[0033] FIG. 2 shows further prior art that manages without any central hydraulic supply. An electromechanical actuator 1 is shown in this Figure whose means for the pressure generation of the hydraulic fluid is designed as fully redundant. It can be recognized that the actuator 1 has two motors 2 and two pumps 7. The use of complete redundancies, however, produces an increase in costs and a higher weight.

[0034] FIG. 3 shows a schematic representation of an actuator in accordance with the invention. This Figure here shows an electrohydraulic actuator with a decentralized hydraulic supply. The central hydraulic supply of the consumer, that is of an element to be adjusted, is here generated by the motor 2 in conjunction with the pump 7 connected to the motor via a mechanical coupling. First drive electronics 1 can furthermore be recognized that are connected to the motor via a first electronic line 5. Besides, there are second drive electronics 4 that are likewise connected to the drive 2 via an electric line 6. Due to the provision of the partial redundancy in which only the drive electronics are designed as completely redundant and the motor is only present in a single design, it is possible to reduce a failure probability without increasing the weight and the costs as in the solution shown in FIG. 2. The electric motor 2 is redundantly controllable here.

[0035] FIG. 4 shows an actuator in accordance with the invention, namely an electromechanical actuator 1. The consumer here is directly connected to the electric motor 2 via a mechanical coupling. The redundant drive electronics 3, 4 do not substantially differ from the drive electronics of FIG. 3 here.

[0036] FIG. 5 shows an electrically redundant electrohydraulic drive for a nose wheel control and for a landing gear actuation. It can be seen here that the actuator 1 has a decentralized hydraulic supply that is driven via the electric motor 2 and the associated hydraulic pump 7. The electric motor 2 is here connected to the first drive electronics 3 via a first electric line 5 and to the second drive electronics 4 via a second electric line 6. It can be made out from the representation of the electric motor 2 that it is an electric motor with a dual winding, with the first winding of the dual winding being controllable by the first drive electronics 3 and the second winding of the dual winding being controllable by the second drive electronics 4. A communications link 8 can also be provided between the two drive electronics 3, 4. A first motor sensor 9 and a second motor sensor 10 are furthermore provided that can be of identical designs with respect to one another. The first motor sensor 9 is here connected to the first drive electronics 3, with the second motor sensor 10 being connected to the second drive electronics 4. All the input parameters (motor sensors 9, 10 or position sensors) required for the drive electronics are thereby designed as redundant and result in a small failure probability of the actuator. The total motor control of the electric motor 2 is also of redundant design since the failure of one drive electronic system 3, 4 can be compensated by the other drive electronic system due to the dual winding.

[0037] FIG. 6 shows an electrically redundantly designed electromechanical actuator for landing gear actuation in which the electronics are integrated in the actuator 1 in a decentralized manner. Due to safety demands, an independent possibility of landing gear extension in emergency operation is typically required by the authorities, which is satisfied by a dual winding motor 2 and the redundant electronics, in particular by the first and second drive electronics 3, 4 and the associated wiring 5, 6. Provision can furthermore be made that the two drive electronics 3, 4 are provided with dissimilar designs. The dissimilarity of the two drive electronics further reduces the failure probability.

[0038] The presented examples of the invention can use a 3-phase permanent synchronous motor with a resolver or a Hall effect sensor for the motor regulation. For the redundant control, the windings of the motor and the motor sensors are in a double configuration, whereby the shaft can be extended due to the higher space requirements. Other motor types are not excluded from the invention in this respect.

[0039] Provision can also be made that the performance of the redundant drives is realized with the same or reduced performance. Both drive electronics can accordingly be switched to active or, in a normal operation in which both drive electronics are functional, only one of the electronics can be switched to active and the other can be held in a standby mode. The advantage of the active-standby concept is found in the identical actuator response on the failure of a redundancy. Alternatively, in the other concept of the active-active operation, a power drop on the failure in one of the drive electronics is system-inherent. This is, however, required at times since in emergency operation, that is operated on the failure of a drive electronic system of certain actuators, a load of the emergency voltage network should be kept as small as possible.

[0040] Provision can additionally be made that the control valves 13 shown in FIG. 5 are implemented in double form and as redundantly controllable (dual coil) valves. The unlocking system 14 shown in FIG. 6 can likewise be required in double form and as a redundantly controllable (dual coil) unlocking device.