An APU bleed air electric actuator capable of automatically shutting down

Abstract

The present invention belongs to the technical field of aviation accessories, and specifically relates to an APU bleed air electric actuator that can be automatically closed, comprising: an electric motor, an electric control mechanism, an bleed air valve, a power-off automatic reset mechanism and a control component. The APU bleed air electric actuator can be automatically closed after power failure at any position to protect the auxiliary power unit (APU) of the aircraft, thereby improving the reliability of the aircraft auxiliary power system and greatly improving flight safety.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation accessories, and in particular relates to an APU bleed air electric actuator which can be automatically closed. Background Art

[0002] Aircraft APU bleed valve is mainly used in the auxiliary power unit (APU) located at the tail end of the aircraft. It controls the on-board control signal to control the on-off of the air turbine starter intake and the adjustment of the air volume. Before the aircraft takes off, the auxiliary power unit (APU) provides power and air source to the aircraft main engine. During the flight of the aircraft, if the main engine stops in the air, the auxiliary power unit (APU) can be started at high altitude at a certain altitude to provide power for the engine to restart. When the auxiliary power unit (APU) suddenly loses power, whether the APU bleed valve electric actuator can effectively cut off the amount of air entering the auxiliary power unit (APU) is crucial to the safety of the aircraft. Therefore, while improving the reliability of the aircraft auxiliary power unit (APU), it is very necessary to increase the safety protection of the APU bleed valve electric actuator for the auxiliary power unit (APU). With the development of all-electric aircraft, the disadvantage of electric actuators that cannot work after power failure has been highlighted. Summary of the invention

[0003] In view of this, the present invention proposes an APU bleed air electric actuator that can be automatically turned off, which can realize the APU bleed air electric actuator that can be automatically turned off after power failure at any position to protect the auxiliary power unit (APU) of the aircraft, thereby improving the reliability of the aircraft auxiliary power system and greatly improving flight safety.

[0004] In order to achieve the above technical objectives, the specific technical solutions adopted by the present invention are:

[0005] An APU bleed air electric actuator capable of automatically closing is used to control the bleed air valve of the APU, comprising: an electric motor, an electric operating mechanism, a bleed air valve, a power-off automatic reset mechanism and a control component;

[0006] The motor is controlled by the control component to output an opening displacement torque for opening the air induction valve and a closing displacement torque for closing the air induction valve by the power-off automatic reset mechanism;

[0007] The electric operating mechanism transmits the opening displacement torque and the closing displacement torque to the air induction valve and the power-off automatic reset mechanism respectively when the electric actuator is powered on;

[0008] The electric operating mechanism transmits the closing displacement torque to the air induction valve when the electric actuator is powered off.

[0009] Furthermore, the electric operating mechanism includes a worm gear, a sun gear, a planetary gear, a planet carrier, an inner gear ring and an electromagnetic brake;

[0010] The worm end of the worm gear is arranged in transmission with the motor, and the worm wheel end of the worm gear is arranged in transmission with the sun gear; the planetary gears are at least two groups, and both are meshed with the sun gear;

[0011] The inner gear ring is meshed with each planetary gear based on the inner teeth; the planet carrier is installed on each of the planetary gears and is also arranged in transmission with the air induction valve and the power-off automatic reset mechanism;

[0012] When the electric actuator is powered on, the electromagnetic brake locks the transmission rotation of the inner gear ring coaxial with the sun gear; when the electric actuator is powered off, the electromagnetic brake disengages the transmission rotation of the inner gear ring coaxial with the sun gear.

[0013] Furthermore, the power-off automatic reset mechanism includes a preload spring and a cam; the cam is arranged in a transmission with the planetary carrier; the electric motor provides an opening displacement torque for the air induction valve and drives the cam to rotate forwardly based on the planetary carrier, and the forward rotation of the cam causes the preload spring to generate a preload force; when the electromagnetic brake disengages the transmission rotation of the inner gear ring coaxial with the sun gear, the preload spring returns and drives the cam to rotate in the opposite direction, and the reverse rotation of the cam outputs the closing displacement torque to the air induction valve.

[0014] Furthermore, the electric motor and the worm end of the worm gear are arranged based on a first reduction spur gear transmission system.

[0015] Furthermore, the electromagnetic brake and the inner gear ring are arranged based on a second reduction spur gear train transmission; the electromagnetic brake and the second reduction spur gear train are steplessly meshed.

[0016] Furthermore, the electric actuator also includes a displacement sensor; the displacement sensor is used to detect the opening amount of the air induction valve; and the detection result is output to the control component.

[0017] Furthermore, the electric actuator also includes a filter; the filter is electrically connected to the control component and is used to transmit discrete signals of the aircraft on which the electric actuator is installed to the control component.

[0018] By adopting the above technical solution, the present invention can bring the following beneficial effects:

[0019] By setting a cam mechanism with constant torque output and an electromagnetic clutch brake in the electric actuator, the aircraft APU bleed valve can be closed with high reliability after any power failure, reducing the harm of ventilation volume to the auxiliary power unit (APU) after power failure, and greatly improving the safety of the auxiliary power unit (APU). At the same time, the power failure automatic reset controller has high integration, light weight, low electrical power, simple control logic, and high practical utilization value. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a working principle diagram of the APU bleed air electric actuator that can be automatically closed in a specific embodiment of the present invention;

[0022] Among them: 1. Electric motor; 2. Electric operating mechanism; 201. First reduction spur gear system; 202. Worm gear; 203. Bearing; 204. Sun gear; 205. Planetary gear; 206. Internal gear ring; 207. Planet carrier; 208. Electromagnetic brake; 209. Second reduction spur gear system; 3. Air induction valve; 4. Automatic reset mechanism in case of power failure; 401. Spring; 402. Cam; 5. Angular displacement sensor; 6. Control component; 601. Controller; 602. Filter; 603. Socket. DETAILED DESCRIPTION

[0023] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0024] The following describes the embodiments of the present disclosure through specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0025] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0026] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The illustrations only show components related to the present disclosure rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0027] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0028] In one embodiment of the present invention, an APU bleed air electric actuator capable of automatically closing is provided to control the bleed air valve 3 of the APU, such as Figure 1 As shown, it includes: a motor 1, an electric operating mechanism 2, an air induction valve 3, a power-off automatic reset mechanism 4 and a control component 6;

[0029] The motor 1 is controlled by the control component 6, and outputs an opening displacement torque for opening the air induction valve 3 and a closing displacement torque for closing the air induction valve 3 by the automatic reset mechanism 4 when power is off;

[0030] The electric operating mechanism 2 transmits the opening displacement torque and the closing displacement torque to the air induction valve 3 and the power-off automatic reset mechanism 4 respectively when the electric actuator is powered on;

[0031] The electric operating mechanism 2 transmits the closing displacement torque to the air induction valve 3 when the electric actuator is powered off.

[0032] In this embodiment, the electric operating mechanism 2 includes a worm gear 202, a sun gear 204, a planetary gear 205, a planetary carrier 207, an inner gear ring 206 and an electromagnetic brake 208;

[0033] The worm end of the worm gear 202 is arranged to be in transmission with the motor 1, and the worm wheel end of the worm gear 202 is arranged to be in transmission with the sun gear 204; there are at least two sets of planetary gears 205, both of which are meshed with the sun gear 204;

[0034] The inner gear ring 206 is meshed with each planetary gear 205 based on the inner teeth; the planet carrier 207 is installed on each planetary gear and is also arranged in transmission with the air induction valve 3 and the power-off automatic reset mechanism 4;

[0035] When the electric actuator is powered on, the electromagnetic brake 208 locks the transmission rotation of the inner gear ring 206 coaxial with the sun gear 204 ; when the electric actuator is powered off, the electromagnetic brake 208 disengages the transmission rotation of the inner gear ring 206 coaxial with the sun gear 204 .

[0036] In this embodiment, the power-off automatic reset mechanism 4 includes a preload spring 401 and a cam 402; the cam 402 is arranged in a transmission with the planetary carrier 207; the motor 1 provides the air inlet valve 3 with an opening displacement torque, while the planetary carrier 207 drives the cam 402 to rotate forward, and the forward rotation of the cam 402 causes the preload spring 401 to generate a preload force; when the electromagnetic brake 208 disengages the transmission rotation of the inner ring gear 206 coaxial with the sun gear 204, the preload spring 401 returns to its position and drives the cam 402 to rotate in the reverse direction, and the reverse rotation of the cam 402 outputs a closing displacement torque to the air inlet valve 3.

[0037] In one embodiment, the electric actuator further includes a displacement sensor; the displacement sensor is used to detect the opening amount of the air induction valve 3; and the detection result is output to the control component 6.

[0038] In some embodiments, the displacement sensor is an angular displacement sensor 5 .

[0039] In this embodiment, the motor 1 and the worm end of the worm gear 202 are arranged based on a transmission of the first reduction spur gear train 201 .

[0040] In one embodiment, the electromagnetic brake 208 and the inner gear ring 206 are arranged based on the second reduction spur gear train 209; the electromagnetic brake 208 is steplessly meshed with the second reduction spur gear train 209. The inner gear ring 206 of this embodiment is provided with external teeth; the external teeth of the inner gear ring 206 are meshed with the second reduction spur gear train 209.

[0041] In this embodiment, the electric actuator further includes a filter 602 ; the filter 602 is electrically connected to the control component 6 , and is used to transmit discrete signals of the aircraft on which the electric actuator is installed to the control component 6 .

[0042] The APU bleed air electric actuator that can be automatically closed in this embodiment includes a motor 1, an electric operating mechanism 2, a bleed air valve 3, a power-off automatic reset mechanism 4, an angular displacement sensor 5 and a control component 6. The flange mounting plate of the motor 1 is connected to the housing of the electric operating mechanism 2 by bolts, and the output shaft of the electric operating mechanism 2 is connected to the valve disc shaft of the bleed air valve 3 by a spline or a branch. The power-off automatic reset mechanism 4 includes a spring 401 and a cam 402, and the cam 402 is connected to the rotating shaft of the bleed air valve 3 by a spline or a branch. The flange mounting plate of the angular displacement sensor 5 is connected to the housing of the electric operating mechanism 2 by bolts, and the rotating shaft is connected to the rotating shaft of the bleed air valve 3 by a flat key. The electric control mechanism 2 comprises a first reduction spur gear train 201, a worm gear 202, a bearing 203, a sun gear 204, a planetary gear 205, an inner gear ring 206, a planetary carrier 207, an electromagnetic brake 208 and a second reduction spur gear train 209; the control component 6 comprises a controller 601, a filter 602 and a socket 603, and the control component 6 is integrated in the housing of the electric control mechanism 2 and is connected to the machine through the socket 603; the air induction valve 3 comprises a valve body, a valve disc, a sealing plate, a rotating shaft, a plug and a bearing 203, and the structural forms include a ball valve, a plug valve and a butterfly valve.

[0043] The outer gear of the inner gear ring 206 in the electric operating mechanism 2 is meshed with the second reduction spur gear system 209, the output shaft of the electromagnetic brake 208 is meshed with the second reduction spur gear system 209, the outer surface of the outer ring of the inner gear ring 206 is pasted with modified polytetrafluoroethylene fabric through a special process to achieve low friction rotation, one end of the first reduction spur gear system 201 is connected to the output shaft of the motor 1 through a pin, and the other end is connected to the worm gear 202 through a locking nut; the angular displacement sensor 5 often uses a precision conductive potentiometer or RVDT to achieve synchronous feedback of the angular position.

[0044] The APU bleed air electric actuator capable of automatically shutting down in this embodiment has the following features:

[0045] Automatic shutdown design when power is lost at any position

[0046] A mechanical automatic reset mechanism is designed in the electric actuator. Through the electromagnetic brake 208 and the stepless meshing of the gears, the electric actuator can be automatically shut down after power failure at any position, completely cutting off the ventilation volume, which can effectively protect the auxiliary power unit APU, avoid safety accidents caused by power failure, and further improve the reliability and safety of the auxiliary power unit APU.

[0047] Low energy consumption design

[0048] In order to realize the automatic closing function of the product in the event of power failure at any position, an automatic reset mechanism 4 is designed. By designing a reasonable contour line of the cam 402, the force arm from the center of the cam 402 to the pressure action line changes accordingly, so that the product of the spring 401 force and the force arm remains constant, thereby obtaining a constant torque that only needs to overcome the closing of the air induction valve 3, greatly reducing the power of the motor 1.

[0049] Combination design

[0050] In order to facilitate the rapid and accurate operation and maintenance of the device in the field, the electric operating mechanism 2, the air bleed valve 3, and the power-off automatic reset mechanism 4 are designed to be combined. The mounting end faces of the electric operating mechanism 2 and the air bleed valve 3 have flange mounting plates, and the mounting end faces of the power-off automatic reset mechanism 4 and the air bleed valve 3 have flange mounting plates, which are easy to maintain.

[0051] Low friction and small size design

[0052] The inner gear ring 206 in the gear train is a key component for the electric control and the power-off automatic reset mechanism 4. The outer surface of the inner gear ring 206 is pasted with modified polytetrafluoroethylene fabric through a special process to achieve low friction and small volume of the inner gear ring 206.

[0053] The working principle of the APU bleed air electric actuator that can be automatically closed in this embodiment is as follows:

[0054] 1. When the system power supply is normal, the motor 1 works. Specifically, the control component 6 supplies power to the electromagnetic brake 208 for braking, and the inner gear ring 206 in the electric operating mechanism 2 is reliably locked through the second reduction spur gear train 209 .

[0055] a. The device issues an operation instruction on the machine, and the device collects the opening instruction of the air induction valve 3 through the socket 603 in the control component 6. The controller 601 analyzes and processes the discrete signal to realize the opening instruction of the air induction valve 3, controls the motor 1 to rotate forward, and drives the air induction valve 3 to move in the opening direction through the output shaft of the electric operating mechanism 2. At the same time, the cam 402 in the power-off automatic reset mechanism 4 is driven to rotate the compression spring 401 through the rotating shaft of the air induction valve 3. The angular displacement sensor 5 feeds back the collected signal of the air induction valve 3 being opened to the controller 601 and the machine through the socket 603. The controller 601 gives the motor 1 a stop instruction. During the whole working process, the angular displacement sensor 5 collects signals in real time, and timely and accurately feeds back the angular position of the air induction valve 3 to the control component 6 and the machine. The machine sends a control current signal in combination with the intake volume demand. The analog current collection and processing circuit in the control component 6 collects and processes the control current, drives the motor 1 to complete the function of the rotation direction and rotation speed instruction information, and thus controls the opening of the air induction valve 3 in real time;

[0056] b. The device issues an operation instruction on the machine, and the device collects the closing instruction of the air induction valve 3 through the socket 603 in the control component 6. The controller 601 analyzes and processes the discrete signal to realize the closing instruction of the air induction valve 3, controls the motor 1 to reverse, and drives the air induction valve 3 to move in the closing direction through the output shaft of the electric operating mechanism 2. The angular displacement sensor 5 feeds back the collected signal of the air induction valve 3 being closed to the controller 601 and the machine through the socket 603. The controller 601 gives the motor 1 a stop working instruction. During the whole working process, the angular displacement sensor 5 collects signals in real time, and timely and accurately feeds back the angular position of the air induction valve 3 to the control component 6 and the machine. The machine sends a control current signal in combination with the intake volume demand. The analog current collection and processing circuit in the control component 6 collects and processes the control current, and drives the motor 1 to complete the function of the rotation direction and rotation speed instruction information, thereby controlling the opening of the air induction valve 3 in real time.

[0057] 2. When the system loses power, the motor 1 is powered off and braked. At the same time, the worm gear 202 in the electric operating mechanism 2 is self-locked, locking the sun gear 204 immobile. The output torque of the power-off automatic reset mechanism 4 is output through the inner ring gear 206 and the planetary carrier 207 to output the rotational torque.

[0058] According to the principle that the force arm from the center of the cam 402 to the pressure action line in the power-off automatic reset mechanism 4 and the force product of the spring 401 are kept constant, the torque provided by the initial preload force of the spring 401 overcomes the closing torque of the air induction valve 3. When a power failure suddenly occurs in the system, the electromagnetic brake 208 is powered off and released, and the spring 401 in the power-off automatic reset mechanism 4 releases the force to push the cam 402 to rotate in the closing direction of the air induction valve 3. The rotating shaft of the air induction valve 3 drives the inner gear ring 206 to rotate through the planet carrier 207, and then releases the torque through the second reduction spur gear train 209 and the electromagnetic brake 208, thereby realizing the automatic closing of the air induction valve 3 after power failure.

[0059] The advantages of the APU bleed air electric actuator that can be automatically closed in this embodiment are as follows:

[0060] This embodiment achieves the function of highly reliable closing of the aircraft APU bleed air valve 3 after any power failure by setting a cam 402 mechanism with constant torque output and an electromagnetic clutch brake in the electric actuator, thereby reducing the harm of the ventilation volume to the auxiliary power unit APU after power failure, and greatly improving the safety of the auxiliary power unit APU. At the same time, the power failure automatic reset control mode has high integration, light weight, low electric power, simple control logic, and high practical utilization value.

[0061] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. An APU bleed air electric actuator capable of automatically closing, used to control the bleed air valve of an APU, characterized in that: include: Electric motor, electric control mechanism, air bleed valve, power-off automatic reset mechanism and control components; The motor is controlled by the control component to output an opening displacement torque for opening the air induction valve and a closing displacement torque for closing the air induction valve by the power-off automatic reset mechanism; The electric operating mechanism transmits the opening displacement torque and the closing displacement torque to the air induction valve and the power-off automatic reset mechanism respectively when the electric actuator is powered on; The electric operating mechanism transmits the closing displacement torque to the air induction valve when the electric actuator is powered off; The electric operating mechanism includes a worm gear, a sun gear, a planetary gear, a planet carrier, an inner gear ring and an electromagnetic brake; The worm end of the worm gear is arranged in transmission with the motor, and the worm wheel end of the worm gear is arranged in transmission with the sun gear; the planetary gears are at least two groups, and both are meshed with the sun gear; The inner gear ring is meshed with each planetary gear based on the inner teeth; the planet carrier is installed on each of the planetary gears and is also arranged in transmission with the air induction valve and the power-off automatic reset mechanism; When the electric actuator is powered on, the electromagnetic brake locks the transmission rotation of the inner gear ring coaxial with the sun gear; when the electric actuator is powered off, the electromagnetic brake disengages the transmission rotation of the inner gear ring coaxial with the sun gear; The power-off automatic reset mechanism includes a preload spring and a cam; the cam is arranged in a transmission with the planetary carrier; the electric motor provides the air induction valve with an opening displacement torque while driving the cam to rotate forwardly based on the planetary carrier, and the forward rotation of the cam causes the preload spring to generate a preload force; when the electromagnetic brake disengages the transmission rotation of the inner gear ring coaxial with the sun gear, the preload spring returns and drives the cam to rotate in the reverse direction, and the reverse rotation of the cam outputs the closing displacement torque to the air induction valve.

2. The electric actuator according to claim 1, characterized in that: The electric motor and the worm end of the worm gear are driven by a first reduction spur gear system.

3. The electric actuator according to claim 1, characterized in that: The electromagnetic brake and the inner gear ring are driven based on a second reduction spur gear train; the electromagnetic brake is steplessly meshed with the second reduction spur gear train.

4. The electric actuator according to claim 1, characterized in that: The electric actuator also includes a displacement sensor; the displacement sensor is used to detect the opening amount of the air induction valve; the detection result of the displacement sensor is output to the control component.

5. The electric actuator according to claim 1, characterized in that: The electric actuator further comprises a filter; the filter is electrically connected to the control component and is used to transmit a discrete signal of the aircraft on which the electric actuator is installed to the control component.

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