Cabin door electromechanical actuator with energy absorption and displacement compensation functions and method

Abstract

The invention discloses a cabin door electromechanical actuator with energy absorption and displacement compensation functions and a method, and relates to aerospace equipment and related fields, the cabin door electromechanical actuator comprises a shell, a lead screw, a lead screw nut, a belleville spring and a wave spring, the shell is provided with a mounting groove, the lead screw is mounted in the mounting groove, and the belleville spring is mounted in the mounting groove relative to the shell; the lead screw has the freedom degree of moving in the axis direction of the lead screw and the freedom degree of rotating around the axis of the lead screw. An elastic mechanism deforming in the axis direction of the lead screw is arranged between the lead screw and the shell. The shell is provided with a driving structure used for driving the lead screw to rotate. The lead screw nut is arranged outside the lead screw in a sleeving mode and is in threaded connection with the lead screw. The lead screw nut is in sliding connection with the shell in the axis direction of the lead screw nut. The shell is connected with the cabin body, and the lead screw nut is connected with the cabin door. The device has energy absorption and buffering effects, and provides corresponding displacement compensation capability for a servo mechanism at the same time.

Description

Technical Field

[0001] The present invention relates to a servo mechanism, and in particular to a cabin door electromechanical actuator and method with energy absorption and displacement compensation functions, belonging to aerospace equipment and related fields. Background Art

[0002] Some aircraft doors open during flight, requiring them to open automatically under the influence of gravity, wind load, etc. This poses two difficulties:

[0003] 1) To ensure the corresponding speed, the servo actuator needs to withstand the impact from the weight of the door and other loads during the door opening process. The high impact energy poses a serious threat to the structure and life of the actuator;

[0004] 2) After the corresponding actuator closes the door, in order to prevent the actuator from excessively squeezing the door, a certain gap needs to be left between the actuator and the door. After the door is closed, the actuator needs to have a certain compensation function for the displacement.

[0005] Taking into account issues such as impact and displacement compensation, most of the existing aircraft door actuators in China currently use hydraulic actuation, and there is currently no corresponding solution for electromechanical door actuators.

[0006] Chinese patent CN 106965919B discloses a novel door actuator, which uses the force generated by the torsion deformation of the torsion bar and the resistance generated by the movement of the buffer to provide resistance for the opening movement of the gangway door.

[0007] The buffering method of the door actuator involved in this patent can only be applied to slowly opening doors and cannot meet the requirements of fast door opening. At the same time, the door actuator does not have the displacement compensation function after the door is closed. Summary of the invention

[0008] The technical problem solved by the present application is: to overcome the deficiencies of the prior art, to provide an electromechanical servo actuator with energy absorption and buffering effects, and at the same time to provide a corresponding displacement compensation capability for the servo mechanism.

[0009] The technical solutions provided by this application are as follows:

[0010] A cabin door electromechanical actuator with energy absorption and displacement compensation functions comprises a housing, a lead screw, a lead screw nut, a disc spring and a wave spring. The housing is provided with a mounting groove, in which the lead screw is mounted. Relative to the housing, the lead screw has the freedom to move along its own axis and the freedom to rotate around its own axis. An elastic mechanism deforming along the axis of the lead screw is provided between the lead screw and the housing; the housing is provided with a driving structure for driving the lead screw to rotate; the lead screw nut is sleeved on the outside of the lead screw and is threadedly connected to the lead screw, and the lead screw nut is slidably connected to the housing along its own axis; the housing is connected to the cabin body, and the lead screw nut is connected to the cabin door.

[0011] The elastic mechanism includes a wave spring and a disc spring, a bearing is arranged between the screw and the inner wall of the mounting groove of the housing, a limiting ring is arranged on the inner wall of the mounting groove of the housing, the bearing is located between the limiting ring and the bottom of the mounting groove, a wave spring is arranged between the bearing and the limiting ring, a disc spring is arranged at the bottom of the mounting groove of the housing, a shaft sleeve is arranged on the outer sleeve of the end of the screw facing the bottom of the mounting groove, the shaft sleeve contacts the side of the bearing away from the limiting ring, and the ends of the screw and the shaft sleeve contact the disc spring.

[0012] The bearing is an angular contact bearing.

[0013] The bearing comprises a first bearing and a second bearing, the second bearing is located at a side of the first bearing away from the limiting ring, the wave spring is located between the first bearing and the limiting ring, and the second bearing is in contact with the shaft sleeve.

[0014] The lead screw sleeve is provided with an annular spring, and the annular spring is located between the annular protrusion and the lead screw nut.

[0015] An annular protrusion is arranged on the outer circumferential surface of the lead screw, the annular protrusion contacts the end of the bearing facing the limiting ring, and the inner diameter of the wave spring is not less than the outer diameter of the annular protrusion.

[0016] The screw is coaxially fixed with a gear, and the gear is located between the first bearing and the second bearing; the driving structure includes a motor and a reduction device connected to the housing, the output shaft of the motor is connected to the input shaft of the reduction device, the output shaft of the reduction device is connected to a driving gear, and the driving gear is meshed with the gear.

[0017] A method for using a hatch door electromechanical actuator with energy absorption and displacement compensation functions, comprising:

[0018] During the door opening process, the motor does not work, and the door pushes the lead screw nut to move. When the lead screw nut moves to the position of the annular spring, it begins to compress the annular spring, and the annular spring begins to absorb kinetic energy and acts as a buffer for the mechanism. After the door is fully opened, the electromagnetic lock is locked, and the annular spring is in a compressed state.

[0019] During the closing process of the hatch, the motor drives the lead screw to rotate, the lead screw drives the lead screw nut to move, and then the lead screw nut pushes the hatch to gradually close. During this process, the lead screw squeezes the first bearing, the first bearing squeezes the second bearing, the second bearing squeezes the sleeve, and finally the force is transmitted to the disc spring, and the disc spring produces compression deformation; until the hatch is completely closed, the actuator electromagnetic lock is locked; and when the hatch is completely closed, there is a reserved gap between the hatch and the cabin body, and finally after the hatch is latched, the lead screw nut is pulled by the hatch, and the lead screw nut of the actuator pulls the lead screw outward to compensate for the gap, the lead screw pushes the second bearing, the first bearing squeezes the wave spring forward to complete the compensation, and the disc spring completes the force release.

[0020] In summary, this application at least includes the following beneficial technical effects:

[0021] (1) The present invention uses an annular spring to absorb the inertial energy impact borne by the servo mechanism after the hatch is opened, playing a role in buffering and absorbing part of the energy.

[0022] (2) The present invention adopts a combination of a wave spring and a disc spring at the support position of the transmission shaft to provide axial displacement compensation for the actuator under the premise that the actuator is locked. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Figure 1 is the structure diagram of the actuator;

[0024] Figure 2 This is an exploded schematic diagram of the actuator;

[0025] Figure 3 It is a cross-sectional view of the actuator through the axis of the lead screw;

[0026] Figure 4 for Figure 3 A partial enlarged view of the actuator.

[0027] Description of the accompanying drawings: 9, motor; 10, reduction gear; 11, housing; 12, ball screw;

[0028] 1. Screw nut; 2. Screw; 21. Gear; 3. Annular spring; 4. Wave spring; 5. First bearing; 6. Second bearing; 7. Bushing; 8. Disc spring. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] The present application embodiment discloses a hatch door electromechanical actuator with energy absorption and displacement compensation functions, such as Figure 1As shown in and 2, it includes a motor 9, a reduction gear 10, a housing 11 and a ball screw 12. The ball screw 12 includes a screw 2 and a screw nut 1. The screw 2 is rotatably installed in the housing 11, and the screw 2 can move along its own axis relative to the housing 11. The screw nut 1 is sleeved on the outside of the screw 2 and is threadedly connected with the screw 2. The screw nut 1 is slidably connected with the housing 11 along the axis of the screw nut 1. As the screw nut 1 rotates, the screw nut 1 can move relative to the axis of the screw 2. The extension and retraction of the screw nut 1 are adjusted by the direction of rotation so that the screw nut 1 extends from one end of the housing 11. The other end of the housing 11 is provided with a first connecting lug, and the first connecting lug is used to connect the cabin. The screw nut 1 is used to connect the cabin door. The motor 9 and the reduction gear 10 are installed in the housing 11, and the servo mechanism drives the screw 2 to rotate through the motor 9 and the reduction gear 10.

[0031] like Figure 3 and Figure 4 As shown, the housing 11 is provided with a mounting groove, the lead screw 2 is rotatably mounted in the mounting groove, and the lead screw nut 1 extends from the open end of the mounting groove. A limit ring is provided on the inner wall of the mounting groove of the housing 11, and the annular spring 3 is sleeved outside the lead screw 2 and located between the limit ring and the lead screw nut 1. The outer circumferential surface of the lead screw 2 is provided with an annular protrusion, and the side of the annular protrusion away from the lead screw nut 1 is the rear part of the lead screw 2. The rear part of the lead screw 2 is supported by the first bearing 5 and the second bearing 6 (rotational connection mode) and is connected to the reduction device 10 through gears. The first bearing 5 and the second bearing 6 are angular contact bearings, and the front end of the lead screw nut 1 is supported by a sliding bearing to ensure that the lead screw nut 1 can perform linear motion. The wave spring 4 is located between the first bearing 5 and the limiting ring, the inner diameter of the wave spring 4 is not less than the outer diameter of the annular protrusion, the second bearing 6 is located on the side of the first bearing 5 away from the limiting ring, the second bearing 6 is provided with a sleeve 7 on the side away from the first bearing 5, and a disc spring 8 is provided at the bottom of the mounting groove, the ends of the screw 2 and the sleeve 7 are in contact with the disc spring 8, so that when the screw 2 moves along its own axial direction, the wave spring 4 is compressed or the disc spring 8 is compressed.

[0032] The screw 2 is coaxially fixed with a gear 21, which is located between the first bearing 5 and the second bearing 6. The output shaft of the motor 9 is connected to the input shaft of the reduction gear 10, and the output shaft of the reduction gear 10 is connected to a driving gear, which meshes with the gear 21. Therefore, the screw 2 can be driven to rotate by the motor 9 and the reduction gear 10, and the screw 2 has the freedom to move along its own axis.

[0033] The basic principles and methods of operation are as follows:

[0034] like Figure 2As shown, the servo mechanism drives the lead screw 2 connected to the reduction device 10 to rotate through the motor 9 to achieve the extension and shortening of the stroke. When the door is opened, the actuator motor 9 does not work, the lead screw shortens, and the external load will push the lead screw nut 1 to move. At this time, the lead screw nut 1 obtains the maximum kinetic energy. In order to absorb the kinetic energy at this time, the annular spring 3 is added for buffering and absorbing energy. When the lead screw nut 1 moves to the position of the annular spring 3, it begins to compress the annular spring 3. The annular spring 3 begins to absorb kinetic energy and plays a buffering role for the mechanism. After the door is opened, the electromagnetic lock is locked, and the annular spring 3 is in a compressed state, completing all buffering and energy absorption.

[0035] During the door closing process, the motor 9 works, driving the lead screw 2 to rotate. When the servo mechanism is extended, the lead screw nut 1 moves forward, and the lead screw 2 moves relatively backward. The lead screw 2 squeezes the first bearing 5, the first bearing 5 squeezes the second bearing 6, and the second bearing 6 squeezes the sleeve 7. Finally, the force is transmitted to the disc spring 8, and the disc spring 8 produces a small compression deformation. When the door is completely closed, the actuator body is in an extended state, and the actuator electromagnetic lock is locked. In order to ensure that the actuator does not over-exert the door, a certain gap needs to be left between the actuator and the door. After the system is bolted, the actuator is stretched, and the actuator is in a locked state. Since the actuator screw cannot rotate at this time, the actuator's shaft system needs to move axially to compensate for the gap. At this time, the actuator's screw nut 1 pulls the screw 2 outward to compensate for the gap, and the screw 2 pushes the second bearing 6. The first bearing 5 squeezes the wave spring 4 forward to complete the compensation. At the same time, to ensure that the transmission system is stable and has no gap, the disc spring 8 completes the force release, squeezes the first bearing 5 to eliminate the bearing raceway gap, ensures the raceway pre-tightening of the first bearing 5 and the second bearing 6, and the actuator realizes the axial displacement compensation function.

[0036] The present invention installs an annular spring at the retracted end of the transmission shaft to absorb the energy impact generated by the hatch inertia and load inertia after the hatch is quickly opened, thereby playing a role in buffering and protecting the actuator;

[0037] The present invention adopts a combination of a wave spring and a disc spring at a supporting position of a transmission shaft to provide axial displacement compensation for the actuator under the premise that the actuator is locked.

[0038] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0039] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A door electromechanical actuator with energy absorption and displacement compensation functions, characterized in that: The invention comprises a housing (11), a lead screw (2), a lead screw nut (1), a disc spring (8) and a wave spring (4); the housing (11) is provided with a mounting groove, the lead screw (2) is mounted in the mounting groove, the lead screw (2) has the freedom to move along its own axis and the freedom to rotate around its own axis relative to the housing (11), an elastic mechanism deforming along the axis of the lead screw (2) is provided between the lead screw (2) and the housing (11); the housing (11) is provided with a driving structure for driving the lead screw (2) to rotate; the lead screw nut (1) is sleeved on the outside of the lead screw (2) and is threadedly connected to the lead screw (2), the lead screw nut (1) is slidably connected to the housing (11) along its own axis; the housing (11) is connected to the cabin body, and the lead screw nut (1) is connected to the cabin door.

2. The electromechanical actuator for a hatch door having energy absorption and displacement compensation functions according to claim 1, characterized in that: The elastic mechanism comprises a wave spring (4) and a disc spring (8); a bearing is arranged between the lead screw (2) and the inner wall of the mounting groove of the housing (11); a limiting ring is arranged on the inner wall of the mounting groove of the housing (11); the bearing is located between the limiting ring and the bottom of the mounting groove; a wave spring (4) is arranged between the bearing and the limiting ring; a disc spring (8) is arranged at the bottom of the mounting groove of the housing (11); a sleeve (7) is arranged on the outer sleeve of the end of the lead screw (2) facing the bottom of the mounting groove; the sleeve (7) contacts the side of the bearing away from the limiting ring; and the ends of the lead screw (2) and the sleeve (7) contact the disc spring (8).

3. The electromechanical actuator for a hatch door with energy absorption and displacement compensation functions according to claim 2, characterized in that: The bearing is an angular contact bearing.

4. The electromechanical actuator for a hatch door having energy absorption and displacement compensation functions according to claim 2, characterized in that: The bearing comprises a first bearing (5) and a second bearing (6), the second bearing (6) being located on a side of the first bearing (5) away from the limiting ring, the wave spring (4) being located between the first bearing (5) and the limiting ring, and the second bearing (6) being in contact with the shaft sleeve (7).

5. The electromechanical actuator for a hatch door with energy absorption and displacement compensation functions according to claim 2, characterized in that: The outer sleeve of the lead screw (2) is provided with an annular spring (3), and the annular spring (3) is located between the annular protrusion and the lead screw nut (1).

6. The electromechanical actuator for a hatch door with energy absorption and displacement compensation functions according to claim 2, characterized in that: The outer circumferential surface of the lead screw (2) is provided with an annular protrusion, the annular protrusion contacts the end of the bearing facing the limit ring, and the inner diameter of the wave spring (4) is not less than the outer diameter of the annular protrusion.

7. The electromechanical door actuator with energy absorption and displacement compensation functions according to claim 4, characterized in that: The lead screw (2) is coaxially fixed with a gear (21), and the gear (21) is located between the first bearing (5) and the second bearing (6); the driving structure comprises a motor (9) and a reduction device (10) connected to the housing (11), the output shaft of the motor (9) is connected to the input shaft of the reduction device (10), the output shaft of the reduction device (10) is connected to a driving gear, and the driving gear is meshed with the gear (21).

8. A method for using a hatch door electromechanical actuator with energy absorption and displacement compensation functions according to any one of claims 1 to 7, characterized in that: include: During the process of opening the hatch, the motor (9) does not work, the hatch pushes the lead screw nut (1) to move, and when the lead screw nut (1) moves to the position of the annular spring (3), it starts to compress the annular spring (3), and the annular spring (3) starts to absorb kinetic energy and acts as a buffer for the mechanism. After the door is fully opened, the electromagnetic lock is locked, and the annular spring (3) is in a compressed state; During the process of closing the hatch, the motor (9) drives the lead screw (2) to rotate, the lead screw (2) drives the lead screw nut (1) to move, and then the lead screw nut (1) pushes the hatch to gradually close. During this process, the lead screw (2) squeezes the first bearing (5), the first bearing (5) squeezes the second bearing (6), the second bearing (6) squeezes the shaft sleeve (7), and finally transmits the force to the disc spring (8), and the disc spring (8) produces compression deformation; until the hatch is completely closed, the actuator electromagnetic lock is locked; and when the hatch is completely closed, there is a reserved gap between the hatch and the cabin body. Finally, after the hatch is latched, the lead screw nut (1) is pulled by the hatch, and the lead screw nut (1) of the actuator pulls the lead screw (2) outward to compensate for the gap, the lead screw (2) pushes the second bearing (6), the first bearing (5) squeezes the wave spring (4) forward to complete the compensation, and the disc spring (8) completes the force release.

Images