CN116080896A - Single-drive pitch synchronous adjusting device and method for coaxial contra-rotating propeller aircraft - Google Patents
Single-drive pitch synchronous adjusting device and method for coaxial contra-rotating propeller aircraft Download PDFInfo
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- CN116080896A CN116080896A CN202211347721.0A CN202211347721A CN116080896A CN 116080896 A CN116080896 A CN 116080896A CN 202211347721 A CN202211347721 A CN 202211347721A CN 116080896 A CN116080896 A CN 116080896A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/30—Blade pitch-changing mechanisms
- B64C11/44—Blade pitch-changing mechanisms electric
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/46—Arrangements of, or constructional features peculiar to, multiple propellers
- B64C11/48—Units of two or more coaxial propellers
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/46—Arrangements of, or constructional features peculiar to, multiple propellers
- B64C11/50—Phase synchronisation between multiple propellers
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- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a single-drive pitch synchronous adjusting device and method of a coaxial disrotatory propeller aircraft, wherein the device comprises a main adjusting seat (1), a front slip ring (2), a base (3), a front propeller hub (4), a front blade (5), a rear blade (6), a front adjusting base (7), a rear slip ring (8), a rear adjusting base (9), a rear propeller hub (10), a motor bracket (12), a first rotating shaft (13), a second rotating shaft (14), a front guide rod (15), a rear guide rod (16), a variable propeller sleeve (17), a cylindrical pin (18), an adjusting push rod (19) and a limiting steel sleeve (20); the method comprises the following steps: and calculating the number of turns n of the servo motor to be rotated, and controlling the servo motor to rotate, so that the front blade (5) and the rear blade (6) on the front hub (4) and the rear hub (5) synchronously rotate. The invention has simple structure and can realize synchronous fine adjustment of angles of the vane parts on different rotating shafts or fixed supports of the coaxial center.
Description
Technical Field
The invention relates to the field of aerospace, in particular to a single-drive pitch synchronous adjusting device and method for a coaxial contra-rotating propeller aircraft.
Background
The coaxial contra-rotating propeller aircraft has the advantages of small volume compared with a single-rotor helicopter and high energy utilization rate in addition to small volume because no tail rotor is needed for providing balance torque, so that the coaxial contra-rotating propeller aircraft is increasingly in an important position in various application fields such as aviation shooting, air monitoring and the like.
The contra-rotating propeller of the existing coaxial contra-rotating propeller aircraft consists of propellers which are respectively arranged on the inner shaft and the outer shaft of the same axis and have opposite steering and same rotating speed. Because the front propeller and the rear propeller turn oppositely, the rear propeller can partially absorb the wake vortex energy loss caused by the front propeller, and the contra-rotating propeller can balance the torque and improve the propulsion efficiency.
However, coaxial contra-rotating propeller aircraft require constant blade pitch changes during operation so that the contra-rotating propeller can operate at optimal blade angles under any operating conditions.
In the prior art, the adjustment of the moving freedom degree and the other two rotating freedom degrees for changing the blade angles of the upper blade and the lower blade is realized through three actuators, or the blade angles of the front blade and the rear blade are respectively and independently adjusted in a double-driving mode.
These solutions make it difficult to achieve a synchronous adjustment of the front and rear blades of the coaxial counter-rotating propeller by means of a single drive or a single actuator.
Disclosure of Invention
The invention aims to provide a single-drive pitch synchronous adjusting device of a coaxial contra-rotating propeller aircraft, which comprises a main adjusting seat, a front slip ring, a base, a front propeller hub, front blades, rear blades, a front adjusting base, a rear slip ring, a rear adjusting base, a rear propeller hub, a motor bracket, a first rotating shaft, a second rotating shaft, a front guide rod, a rear guide rod, a variable propeller sleeve, a cylindrical pin, an adjusting push rod and a limiting steel sleeve.
The end face of the main adjusting seat is provided with a threaded hole, and the threaded hole is matched with the external thread of the screw rod, so that the screw rod is connected to the main adjusting seat.
The main adjusting seat is connected with the front slip ring through a rolling bearing.
The main adjusting seat and the front slip ring can move together in the axial direction, and the main adjusting seat and the front slip ring can rotate around the axial line.
The end face of the main adjusting seat is provided with a guide rod mounting hole, and the guide rod mounting hole is used for mounting a guide rod.
The base is coaxial with the front hub.
A group of rolling bearings are arranged between the inner cylindrical surface of the base and the outer cylindrical surface of the front propeller hub, and a steel sleeve is arranged between the rolling bearings.
The inner ring of the rolling bearing between the base and the front propeller hub is axially limited by two lock nuts, and the outer ring of the bearing is limited by a motor bracket.
The front propeller hub is provided with a plurality of first through holes, and the first through holes are used for installing front propeller blades.
And a plurality of front guide rod mounting holes are formed in the plane, perpendicular to the axis, of the front propeller hub.
The front hub is keyed to the first rotor shaft.
The front adjusting base is connected with the rear sliding ring through a rolling bearing.
The front adjustment base and the rear slip ring are jointly movable in the axial direction. The front adjustment base and the rear slip ring are rotatable relative to each other about an axis.
And the front adjusting base and the rear adjusting base are respectively provided with an adjusting push rod mounting hole.
And a plurality of second through holes are formed in the rear hub and are used for installing rear paddles.
And a plurality of rear guide rod mounting holes are formed in the plane, perpendicular to the axis, of the rear hub.
The rear hub is connected with the second rotating shaft through a key.
The motor support is used for installing a servo motor.
The end face of the motor support is provided with a third through hole, the third through hole is matched with the guide sleeve, and the guide sleeve is matched with the guide rod arranged on the main adjusting seat, so that the main adjusting seat can only slide along the axial direction.
The front guide rod passes through a front guide rod mounting hole on the front propeller hub and then is connected with the front adjusting base, and the other end of the front guide rod is connected with the front slip ring.
One end of the rear guide rod penetrates through a rear guide rod mounting hole in the rear propeller hub and then is connected with the rear adjusting base, and the other end of the rear guide rod is connected with the rear slip ring.
The variable pitch sleeve is connected with the adjusting push rod through a pin shaft, and the pin shaft is prevented from falling off by a clamping ring.
The variable pitch sleeve is fixedly connected with the front blade and the rear blade through cylindrical pins.
One end of the adjusting push rod penetrates through the adjusting push rod mounting holes on the front adjusting base and the rear adjusting base and is connected with the front adjusting base and the rear adjusting base through threaded pins; the other end of the adjusting push rod is connected with the variable pitch sleeve in the front blade and the rear blade.
And the outer part of the limiting steel sleeve is contacted with the circular plane of the inner surfaces of the front propeller hub and the rear propeller hub for preventing the blades from falling out.
Further, when the adjusting device works, the servo motor drives the screw rod to rotate, so that the main adjusting seat moves, and further the front adjusting base and the rear adjusting base synchronously move, and the front blades and the rear blades on the front propeller hubs and the rear propeller hubs synchronously rotate.
Further, a plurality of blade assembly mounting holes with the same size, namely first through holes, are uniformly distributed on the outer cylindrical surface of the front hub along the circumference.
The outer cylindrical surface of the rear propeller hub is uniformly provided with a plurality of blade mounting holes with the same size along the circumference, namely second through holes.
Further, the spline housing is also included.
The spline housing is fixed with the front propeller hub, and the internal spline of the spline housing is connected with the front propeller hub
The first rotating shaft external spline is matched with the first rotating shaft external spline to limit the circumferential mutual rotation of the front hub and the first rotating shaft, and the axial directions of the front hub and the first rotating shaft are limited through the clamping ring.
The front propeller hub is connected with the second rotating shaft through a bearing, and the bearing plays a supporting role.
The rear hub is matched with the external spline on the second rotating shaft through the internal spline. The internal spline is used for limiting the mutual rotation of the rear hub and the second rotating shaft.
A shaft sleeve is arranged between the front propeller hub and the rear propeller hub, a locking nut is arranged at the tail part of the second rotating shaft, and the position of the axis of the rear propeller hub is limited. One side of the shaft sleeve is contacted with the end face of the inner ring of the bearing for supporting the front hub, the other side of the shaft sleeve is contacted with the inner end face of the rear hub, and the front hub and the rear hub do not interfere with each other.
Further, the two ends of the rear guide rod are respectively connected with the rear sliding ring and the rear adjusting base and fixedly connected with the rear adjusting base through the inner hexagon screw and the hexagon nut.
Further, a circlip is included.
And the elastic retainer ring limits the axial direction of the rolling bearing.
Further, the shape of the adjusting push rod mounting hole comprises a straight-sided ellipse.
Further, one end of the adjusting push rod is connected with the front adjusting base and the rear adjusting base through threaded pins, and the other end of the adjusting push rod is connected with a variable pitch sleeve on the front blade assembly through a pin shaft and a clamping ring.
Further, the first through holes and the second through holes are uniformly distributed in the circumferential direction.
The method for using the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft comprises the following steps:
1) Measuring and obtaining the initial angle theta of the front blade and the rear blade 1 Length of pitch sleeve l 1 Adjusting the length l of the push rod 2 。
2) Determining a desired adjusted blade angle θ 2 。
3) Calculating the distance between the axis of the front blade rotating shaft before and after adjustment and the axis of the round hole of the front adjusting base provided with the threaded pin, or calculating the distance between the axis of the rear blade rotating shaft before and after adjustment and the axis of the round hole of the rear adjusting base provided with the threaded pin, namely:
4) Adjusting the moving distance L of the base before calculation 1 And adjusting the moving distance L of the base 2 The method comprises the following steps:
L 1 ＝L 2 ＝x 2 -x 1 (3)
5) Calculating the number of turns n of the servo motor, namely:
wherein p is the lead of the lead screw. Distance l=l 1 ＝L 2 ；
6) The servo motor is controlled to rotate according to the number of rotation turns n of the servo motor, so that the main adjusting seat is moved, the front adjusting base and the rear adjusting base are further moved synchronously, and the front blades and the rear blades on the front propeller hubs and the rear propeller hubs are synchronously rotated. The technical effect of the invention is undoubtedly that the invention has the following advantages:
1) Only one driving part is used for driving the angle adjusting device, so that the energy consumption is low and the reliability is high;
2) The device has simple structure, and can realize synchronous fine adjustment of angles of the blade parts on different rotating shafts or fixed supports of the coaxial center;
3) The mechanism is integrally symmetrical, the sizes of all parts of the front-back angle adjusting device are the same, and the angle adjustment synchronism is good;
4) The mechanism has good guiding performance and high adjustment precision, and the rotating shaft can still keep good stability even if rotating at a high speed;
5) The device occupies small space, is convenient to adjust, and can be suitable for various complex working conditions;
6) The invention can replace the blade with a cutter and other parts, the universality of the device is stronger, and the application range is wider.
Drawings
FIG. 1 is a schematic diagram of an oblique view of the present invention;
FIG. 2 is a cross-sectional view of FIG. 1;
FIG. 3 is a schematic diagram of the primary mechanism of the present invention;
FIG. 4 is a schematic structural view of a front blade assembly;
FIG. 5 is a schematic structural view of a rear slip ring;
FIG. 6 is a schematic diagram of the principle of operation of the primary mechanism of the present invention;
FIG. 7 is a partial cross-sectional view of the front blade assembly;
in the figure: the main adjusting seat 1, the front slip ring 2, the base 3, the front hub 4, the front blade 5, the rear blade 6, the front adjusting base 7, the rear slip ring 8, the rear adjusting base 9, the rear hub 10, the spline housing 11, the motor bracket 12, the first rotating shaft 13, the second rotating shaft 14, the front guide rod 15, the rear guide rod 16, the pitch sleeve 17, the cylindrical pin 18, the adjusting push rod 19, the limiting steel sleeve 20, the guide rod 21 and the guide sleeve 22.
Detailed Description
The present invention is further described below with reference to examples, but it should not be construed that the scope of the above subject matter of the present invention is limited to the following examples. Various substitutions and alterations are made according to the ordinary skill and familiar means of the art without departing from the technical spirit of the invention, and all such substitutions and alterations are intended to be included in the scope of the invention.
Example 1:
referring to fig. 1 to 7, the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller comprises a main adjusting seat 1, a front slip ring 2, a base 3, a front propeller hub 4, a front blade 5, a rear blade 6, a front adjusting base 7, a rear slip ring 8, a rear adjusting base 9, a rear propeller hub 10, a motor bracket 12, a first rotating shaft 13, a second rotating shaft 14, a front guide rod 15, a rear guide rod 16, a pitch sleeve 17, a cylindrical pin 18, an adjusting push rod 19 and a limiting steel sleeve 20.
The end face of the main adjusting seat 1 is provided with a threaded hole, and the threaded hole is matched with the external thread of the screw rod, so that the screw rod is connected to the main adjusting seat 1.
The main adjusting seat 1 is connected with the front slip ring 2 through a rolling bearing.
The main adjusting seat 1 and the front sliding ring 2 can move together in the axial direction, and the main adjusting seat 1 and the front sliding ring 2 can rotate around the axial line.
The end face of the main adjusting seat 1 is provided with a guide rod mounting hole, and the guide rod mounting hole is used for mounting a guide rod.
The inner ring of the rolling bearing between the base 3 and the front propeller hub 4 is axially limited by two locking nuts, and the outer ring of the bearing is limited by a motor bracket;
specifically, the base 3 and the front propeller hub 4 are coaxial, a group of rolling bearings are arranged between the outer cylindrical surface of the front propeller hub 4 and the inner cylindrical surface of the base 3, a steel sleeve is arranged between the two rolling bearings, external threads are processed on the front propeller hub 4, the bearing inner ring is axially limited through a nut, and the bearing outer ring is limited through the end surface of the motor bracket 12, so that the front propeller hub 4 can only rotate around the base;
the front hub 4 is provided with a plurality of first through holes, and the first through holes are used for installing the front blades 5.
A plurality of front guide rod mounting holes are formed in the plane, perpendicular to the axis, of the front propeller hub 4.
The front hub 4 is keyed to the first shaft 13.
The front adjusting base 7 and the rear slip ring 8 are connected through a rolling bearing.
The front adjustment base 7 and the rear slip ring 8 are jointly movable in the axial direction. The front adjustment base 7 and the rear slip ring 8 are rotatable relative to each other about an axis.
The front adjusting base 7 and the rear adjusting base 9 are respectively provided with an adjusting push rod mounting hole.
The rear hub 10 is provided with a plurality of second through holes, and the second through holes are used for installing the rear blades 6.
The rear hub 10 is provided with a plurality of rear guide rod mounting holes on a plane perpendicular to the axis.
The rear hub 10 is keyed to the second shaft 14.
The motor bracket 12 is used for installing a servo motor.
The end face of the motor bracket 12 is provided with a third through hole, the third through hole is matched with a guide sleeve 22, and the guide sleeve 22 is matched with a guide rod 21 arranged on the main adjusting seat 1, so that the main adjusting seat 1 can only slide along the axial direction.
The front guide rod 15 passes through a front guide rod mounting hole on the front propeller hub 4 and then is connected with the front adjusting base 7, and the other end of the front guide rod is connected with the front slip ring 2.
One end of the rear guide rod 16 passes through a rear guide rod mounting hole on the rear hub 10 and then is connected with the rear adjustment base 9, and the other end is connected with the rear slip ring 8.
The variable pitch sleeve 17 is connected with the adjusting push rod 19 through a pin shaft, and the pin shaft is prevented from falling off by a clamping ring;
the pitch control sleeve 17 is fixedly connected with the front/rear blades through cylindrical pins 18;
one end of the adjusting push rod 19 passes through adjusting push rod mounting holes on the front adjusting base 7 and the rear adjusting base 9 and is connected with the front adjusting base 7 and the rear adjusting base 9 through threaded pins; the other end of the adjusting push rod 19 is connected with the variable pitch sleeves in the front blade 5 and the rear blade 6.
The limiting steel sleeve 20 is arranged between the front/rear blade and the variable pitch sleeve, the inner surface of the front/rear blade hub is provided with a circular plane at the position where the through hole of the front/rear blade is arranged, and the outer part of the limiting steel sleeve is contacted with the circular plane of the inner surface of the front/rear blade hub for preventing the blade from falling off;
when the adjusting device works, the servo motor drives the screw rod to rotate, so that the main adjusting seat 1 moves, and further the front adjusting base 7 and the rear adjusting base 9 synchronously move, and the front blades 5 and the rear blades 6 on the front propeller hubs 4 and the rear propeller hubs 10 synchronously rotate.
The outer cylindrical surface of the front propeller hub 4 is uniformly provided with a plurality of blade assembly mounting holes with the same size along the circumference, namely first through holes.
The outer cylindrical surface of the rear hub 10 is uniformly provided with a plurality of blade mounting holes with the same size, namely second through holes along the circumference.
And also includes a spline housing 11.
The spline housing 11 is fixed with the front propeller hub 4, and the internal spline of the spline housing 11 is connected with
The external splines of the first rotating shaft 13 are matched to limit the circumferential mutual rotation of the front hub 4 and the first rotating shaft 13, and limit the axial directions of the front hub 4 and the first rotating shaft 13 through the clamping ring.
The front hub 4 is connected with the second rotating shaft 14 through a bearing, and the bearing plays a supporting role.
The rear hub 10 is engaged with external splines on the second shaft 14 by internal splines. The internal spline is used to limit the mutual rotation of the rear hub 10 and the second shaft 14.
A shaft sleeve is arranged between the front propeller hub 4 and the rear propeller hub 10, a locking nut is arranged at the tail part of the second rotating shaft, and the axial position of the rear propeller hub is limited. One side of the shaft sleeve is contacted with the end face of the inner ring of the bearing for supporting the front hub, the other side of the shaft sleeve is contacted with the inner end face of the rear hub, and the front hub 4 and the rear hub 10 do not interfere with each other.
Two ends of the rear guide rod 16 are respectively connected with the rear sliding ring 8 and the rear adjusting base 9 and fixedly connected with the rear adjusting base through socket head cap screws and hexagon nuts.
And the elastic retainer ring is also included.
And the elastic retainer ring limits the axial direction of the rolling bearing.
The shape of the adjusting push rod mounting hole comprises a straight-edge ellipse.
One end of the adjusting push rod 9 is connected with the front adjusting base 7 and the rear adjusting base 9 through threaded pins, and the other end of the adjusting push rod is connected with a variable pitch sleeve 17 on the front blade assembly through a pin shaft and a clamping ring.
All the adjusting push rods (9) are connected with the front/rear adjusting base at one side and connected with the variable pitch sleeve (17) in the front/rear blade assembly at the other side; (the adjusting push rod (9) is not directly connected with the front/rear paddles, and the variable paddle sleeve is fixedly connected with the front/rear paddles through cylindrical pins);
the fore/aft blade assemblies each include: front/rear paddles, a paddle changing sleeve, a limiting steel sleeve and a cylindrical pin; (these parts are integral during adjustment and move simultaneously).
The first through holes and the second through holes are uniformly distributed in the circumferential direction.
The method for using the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft comprises the following steps:
1) Measuring and obtaining the initial angles theta of the front blade 5 and the rear blade 6 1 Length l of pitch sleeve 17 1 Adjusting the length l of the push rod 19 2 。
2) Determining a desired adjusted blade angle θ 2 。
3) Calculating the distance x between the axis of the rotating shaft of the front blade 5/rear blade 6 and the axis of the round hole of the threaded pin on the front adjusting base 7/rear adjusting base 9 before and after adjustment 1 Distance x 2 The method comprises the following steps:
if the initial angle of the front blade (5) is measured in the step 1, the distance calculated in the step 3 is the frontThe distance between the axis of the blade rotating shaft and the axis of the round hole corresponding to the front adjusting base and provided with the threaded pin. If the initial angle of the rear blade (6) is measured in the step 1, the same is true. I.e. when θ 1 、θ 2 When the initial angle of the front blade and the adjusted blade angle are adopted, x is 1 、x 2 The distance between the axis of the front blade rotating shaft and the axis of the round hole of the front adjusting base, on which the threaded pin is arranged, is shown. When theta is as 1 、θ 2 When the initial angle of the rear blade and the adjusted blade angle are adopted, x 1 、x 2 The distance between the axis of the rotating shaft of the rear blade and the axis of the round hole of the threaded pin arranged on the rear adjusting base before and after adjustment is shown.
4) Calculate the moving distance L of the pre-adjustment base 7 1 And the moving distance L of the rear adjustment base 9 2 The method comprises the following steps:
L 1 ＝L 2 ＝x 2 -x 1 (3)
5) Calculating the number of turns n of the servo motor, namely:
wherein p is the lead of the lead screw. Distance l=l 1 ＝L 2 ；
6) The servo motor is controlled to rotate according to the number of rotation turns n of the servo motor, so that the main adjusting seat 1 is moved, the front adjusting base 7 and the rear adjusting base 9 are further moved synchronously, and the front blades 5 and the rear blades 6 on the front propeller hubs 4 and the rear propeller hubs 10 are synchronously rotated.
Example 2:
in this embodiment, the number of front blades and the number of rear blades of the coaxial counter-rotating propeller are 6 and 4, respectively. The single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft comprises: the main adjusting seat 1, the front sliding ring 2, the base 3, the front adjusting base 7, the rear sliding ring 8, the rear adjusting base 9, the front guide rod 15, the rear guide rod 16, the front blade 5, the rear blade 6, the adjusting push rod 19, the motor bracket 12, the front blade hub 4, the rear blade hub 10, the motor bracket 12, the first rotating shaft 13, the second rotating shaft 14, the pitch sleeve 17, the cylindrical pin 18 and the limiting steel sleeve 20.
Pitch refers to the distance that the rotor or fixed wing propeller of a helicopter travels up or forward with 360 degrees of rotation. The greater the angle of inclination between the blades of the propeller and the plane of rotation, the greater the pitch, and when the angle of the blades and the plane of rotation is 0, the pitch is also 0.
The device is divided into a front inclination angle adjusting mechanism and a back inclination angle adjusting mechanism, wherein the front inclination angle adjusting mechanism and the back inclination angle adjusting mechanism are composed of a plurality of crank block mechanisms uniformly distributed along the circumferential direction, and the number of the mechanisms can be adjusted according to actual requirements; the crank in the crank slide block mechanism is a variable pitch sleeve, the connecting rod is an adjusting push rod, and the slide blocks are respectively a front adjusting base and a rear adjusting base.
A plurality of through holes are circumferentially and uniformly distributed on the front propeller hub 4 and the rear propeller hub 10 and are used for installing blades 5; the front propeller hub 4 is perpendicular to an axis plane and is provided with three front guide rod mounting holes, a plurality of blade assembly 5 mounting holes with the same size are uniformly distributed on the outer cylindrical surface of the front propeller hub along the circumference, the front guide rods penetrate through the guide rod mounting holes on the front propeller hub and are connected with the front adjusting base 7 and are fixed through inner hexagon screws, the spline housing is fixedly connected with the front propeller hub through the screw mounting holes by utilizing the inner hexagon screws, and the inner spline of the spline housing and the outer spline of the first rotating shaft are matched and limited to circumferentially rotate mutually and limit the axis direction of the spline housing by utilizing the clamping ring.
Three rear guide rod mounting holes are formed in the plane, perpendicular to the axis, of the rear propeller hub 10, a plurality of blade mounting holes with the same size are uniformly distributed on the outer cylindrical surface of the rear propeller hub along the circumference of the rear guide rod, the rear guide rods pass through the rear guide rod mounting holes in the rear propeller hub, and the two ends of each rear guide rod are respectively connected with the rear slip ring 8 and the rear adjustment base 9 and fixedly connected through socket head cap screws; the front hub 4 and the rear hub 10 are respectively connected with the first rotating shaft and the second rotating shaft in a key way.
The front adjusting base and the rear sliding ring are connected through the rolling bearing, the elastic retainer ring is used for limiting the axis direction of the rolling bearing, the front adjusting base and the rear sliding ring can move together in the axis direction, and meanwhile, the front adjusting base and the rear sliding ring can rotate around the axis.
The main adjusting seat is connected with the front slip ring through the rolling bearing, the elastic retainer ring is used for limiting the axis direction of the rolling bearing, the adjusting base and the front slip ring can jointly move in the axis direction, and meanwhile, the adjusting base and the front slip ring can mutually rotate around the axis.
The installation holes of the adjusting push rods 19 on the front adjusting base 7 and the rear adjusting base 9 are in runway shapes, one end of each adjusting push rod 19 penetrates through the installation holes of the adjusting push rods on the front adjusting base 7 and the rear adjusting base 9 and is connected with the front adjusting base 7 and the rear adjusting base 9 through threaded pins, and the other end of each adjusting push rod 19 is connected with the pitch control sleeve 17 through a shaft and a clamping ring.
The end face of the main adjusting seat 1 is provided with a threaded hole, and the internal thread is matched with the external thread of the screw rod; the end face of the main adjusting seat 1 is provided with a guide rod mounting hole for mounting a guide rod, and the guide rod is in tight fit with the guide rod mounting hole.
The rear blade 6 is used for installing a servo motor, a through hole is formed in the end face of the rear blade, the through hole is in tight fit with a guide sleeve, and the guide sleeve is matched with a guide rod arranged on the main adjusting seat 1, so that the main adjusting seat 1 can only slide along the axial direction.
The screw rod is driven to rotate through the servo motor, the main adjusting seat 1 moves successively, the front adjusting base and the rear adjusting base move synchronously, and finally synchronous rotation of blades on the front propeller hub and the rear propeller hub is realized.
The adjusting steps are as follows:
step one: obtaining the initial angle theta of the blade 1 And the final angle theta after the required adjustment 2 At the same time set the crank length as l 1 The length of the connecting rod is l 2 ；
Step two: by the dimension parameter and the angle theta of the crank slide block mechanism 1 、θ 2 Obtaining the distance x between the rotating shaft of the blade in the crank block mechanism and the main adjusting seat 1 before and after the distance adjustment 1 、x 2 The method comprises the following steps of:
step three: according to the distance value x obtained in the step two 1 And x 2 The obtained slide movement distance L is:
L＝x 2 -x 1
step four: the lead screw p is that the lead screw rotates one circle, the moving distance of the nut can be known, and the rotation number of turns n of the angle servo motor required by rotation is as follows:
example 3:
the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft comprises a main adjusting seat 1, a front slip ring 2, a base 3, a front propeller hub 4, a front propeller blade 5, a rear propeller blade 6, a front adjusting base 7, a rear slip ring 8, a rear adjusting base 9, a rear propeller hub 10, a motor bracket 12, a first rotating shaft 13, a second rotating shaft 14, a front guide rod 15, a rear guide rod 16, a variable propeller sleeve 17, a cylindrical pin 18, an adjusting push rod 19 and a limiting steel sleeve 20.
The end face of the main adjusting seat 1 is provided with a threaded hole which is matched with the external thread of the screw rod, so that the screw rod is connected to the main adjusting seat 1;
the main adjusting seat 1 is connected with the front slip ring 2 through a rolling bearing;
the main adjusting seat 1 and the front sliding ring 2 can jointly move in the axial direction, and the main adjusting seat 1 and the front sliding ring 2 can mutually rotate around the axial line;
the end face of the main adjusting seat 1 is provided with a guide rod mounting hole, and the guide rod mounting hole is used for mounting a guide rod;
the base 3 is coaxial with the front hub 4;
a group of rolling bearings are arranged between the inner cylindrical surface of the base 3 and the outer cylindrical surface of the front propeller hub 4, and a steel sleeve is arranged between the rolling bearings;
the inner ring of the rolling bearing between the base 3 and the front propeller hub 4 is axially limited by two locking nuts, and the outer ring of the bearing is limited by a motor bracket;
the front propeller hub 4 is provided with a plurality of first through holes, and the first through holes are used for installing front propeller blades 5;
a plurality of front guide rod mounting holes are formed in the plane, perpendicular to the axis, of the front propeller hub 4;
the front hub 4 is keyed to the first shaft 13.
The front adjusting base 7 and the rear slip ring 8 are connected through a rolling bearing;
the front adjusting base 7 and the rear slip ring 8 can move together in the axial direction; the front adjusting base 7 and the rear slip ring 8 can mutually rotate around an axis;
the front adjusting base 7 and the rear adjusting base 9 are respectively provided with an adjusting push rod mounting hole;
the rear hub 10 is provided with a plurality of second through holes, and the second through holes are used for installing the rear blades 6;
a plurality of rear guide rod mounting holes are formed in the plane, perpendicular to the axis, of the rear hub 10;
the rear hub 10 is in key connection with the second rotating shaft 14;
the motor bracket 12 is used for installing a servo motor;
a third through hole is formed in the end face of the motor bracket 12, the third through hole is matched with a guide sleeve 22, and the guide sleeve 22 is matched with a guide rod 21 arranged on the adjusting seat, so that the main adjusting seat 1 can only slide along the axial direction;
the front guide rod 15 passes through a front guide rod mounting hole on the front propeller hub 4 and then is connected with the front adjusting base 7, and the other end of the front guide rod is connected with the front slip ring 2;
one end of the rear guide rod 16 passes through a rear guide rod mounting hole on the rear hub 10 and then is connected with the rear adjustment base 9, and the other end of the rear guide rod is connected with the rear slip ring 8;
the variable pitch sleeve 17 is connected with the adjusting push rod 19 through a pin shaft, and the pin shaft is prevented from falling off by a clamping ring;
the variable pitch sleeve 17 is fixedly connected with the front blade 5 and the rear blade 6 through a cylindrical pin 18;
one end of the adjusting push rod 19 passes through adjusting push rod mounting holes on the front adjusting base 7 and the rear adjusting base 9 and is connected with the front adjusting base 7 and the rear adjusting base 9 through threaded pins; the other end of the adjusting push rod 19 is connected with the variable pitch sleeves in the front blade 5 and the rear blade 6;
and the limiting steel sleeve 20 is respectively arranged between the front blade 5, the rear blade 6 and the variable pitch sleeve, and the outer part of the limiting steel sleeve 20 is contacted with the circular plane of the inner surfaces of the front propeller hub 4 and the rear propeller hub 10 for preventing the blades from falling out.
Example 4:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein when the adjusting device works, a servo motor drives a screw rod to rotate, so that a main adjusting seat 1 moves, and further a front adjusting base 7 and a rear adjusting base 9 synchronously move, and the front blade 5 and the rear blade 6 on a front propeller hub 4 and a rear propeller hub 10 synchronously rotate.
Example 5:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein a plurality of blade assembly mounting holes with the same size, namely first through holes, are uniformly distributed on the outer cylindrical surface of the front propeller hub 4 along the circumference;
the outer cylindrical surface of the rear hub 10 is uniformly provided with a plurality of blade mounting holes with the same size, namely second through holes along the circumference.
Example 6:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein the single-drive pitch synchronous adjusting device also comprises a spline housing 11;
the spline housing 11 is fixed with the front propeller hub 4, and the internal spline of the spline housing 11 is connected with
The external splines of the first rotating shaft 13 are matched to limit the circumferential mutual rotation of the front hub 4 and the first rotating shaft 13, and limit the axial directions of the front hub 4 and the first rotating shaft 13 through a clamping ring;
the front propeller hub 4 is connected with the second rotating shaft 14 through a bearing, and the bearing plays a supporting role;
the rear hub 10 is matched with an external spline on the second rotating shaft 14 through an internal spline; the internal spline is used for limiting the mutual rotation of the rear hub 10 and the second rotating shaft 14;
a shaft sleeve is arranged between the front propeller hub 4 and the rear propeller hub 10, a locking nut is arranged at the tail part of the second rotating shaft, and the axial position of the rear propeller hub is limited; one side of the shaft sleeve is contacted with the end face of the inner ring of the bearing for supporting the front hub, the other side of the shaft sleeve is contacted with the inner end face of the rear hub, and the front hub 4 and the rear hub 10 do not interfere with each other.
Example 7:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein two ends of the rear guide rod 16 are respectively connected with the rear slip ring 8 and the rear adjusting base 9 and are fixedly connected through an inner hexagon screw and a hexagon nut.
Example 8:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein the device also comprises a circlip;
and the elastic retainer ring limits the axial direction of the rolling bearing.
Example 9:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is as shown in the embodiment 3, wherein the shape of the adjusting push rod mounting hole comprises a straight-edge ellipse.
Example 10:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein one end of the adjusting push rod 9 is connected with the front adjusting base 7 and the rear adjusting base 9 through threaded pins, and the other end of the adjusting push rod is connected with the pitch changing sleeve 17 on the front blade assembly through a pin shaft and a clamping ring.
Example 11:
the main content of the single-drive pitch synchronous adjusting device of the coaxial contra-rotating propeller aircraft is shown in the embodiment 3, wherein the first through holes and the second through holes are uniformly distributed in the circumferential direction;
example 12:
the method of using the single drive pitch synchronous adjustment device of coaxial contra-rotating propeller aircraft of embodiments 1-11, comprising the steps of:
1) Before measurement is obtainedInitial angle θ of blade 5 and rear blade 6 1 Length l of pitch sleeve 17 1 Adjusting the length l of the push rod 19 2 ；
2) Determining a desired adjusted blade angle θ 2 ；
3) The distance between the rotating shaft axis of the front blade 5 and the rotating shaft axis of the rear blade 6 and the rotating shaft axis of the round hole of the threaded pin on the rear adjusting base 9 are calculated, namely:
wherein x is 1 For the distance before adjustment; x is x 2 Is the adjusted distance;
3) Calculate the moving distance L of the pre-adjustment base 7 1 And the moving distance L of the rear adjustment base 9 2 The method comprises the following steps:
L 1 ＝L 2 ＝x 2 -x 1
4) Calculating the number of turns n of the servo motor, namely:
wherein p is the lead of the lead screw; distance l=l 1 ＝L 2 ；
5) The servo motor is controlled to rotate according to the number of rotation turns n of the servo motor, so that the main adjusting seat 1 is moved, the front adjusting base 7 and the rear adjusting base 9 are further moved synchronously, and the front blades 5 and the rear blades 6 on the front propeller hubs 4 and the rear propeller hubs 10 are synchronously rotated.
Claims (10)
1. The utility model provides a coaxial disrotatory propeller aircraft's single drive pitch synchronous regulation device which characterized in that: the novel variable-pitch propeller comprises a main adjusting seat (1), a front slip ring (2), a base (3), a front propeller hub (4), front paddles (5), rear paddles (6), a front adjusting base (7), a rear slip ring (8), a rear adjusting base (9), a rear propeller hub (10), a motor bracket (12), a first rotating shaft (13), a second rotating shaft (14), a front guide rod (15), a rear guide rod (16), a variable-pitch sleeve (17), a cylindrical pin (18), an adjusting push rod (19) and a limiting steel sleeve (20).
The end face of the main adjusting seat (1) is provided with a threaded hole which is matched with the external thread of the screw rod, so that the screw rod is connected to the main adjusting seat (1);
the main adjusting seat (1) is connected with the front slip ring (2) through a rolling bearing;
the main adjusting seat (1) and the front slip ring (2) can move together in the axial direction, and the main adjusting seat (1) and the front slip ring (2) can rotate around the axial line;
the end face of the main adjusting seat (1) is provided with a guide rod mounting hole, and the guide rod mounting hole is used for mounting a guide rod;
the base (3) is coaxial with the front hub (4);
a group of rolling bearings are arranged between the inner cylindrical surface of the base (3) and the outer cylindrical surface of the front propeller hub (4), and a steel sleeve is arranged between the rolling bearings;
the inner ring of the rolling bearing between the base (3) and the front propeller hub (4) is axially limited by two locking nuts, and the outer ring of the bearing is limited by a motor bracket;
a plurality of first through holes are formed in the front propeller hub (4), and the first through holes are used for installing front paddles (5);
a plurality of front guide rod mounting holes are formed in a plane, perpendicular to the axis, of the front propeller hub (4);
the front hub (4) is keyed to the first shaft (13).
The front adjusting base (7) is connected with the rear sliding ring (8) through a rolling bearing;
the front adjusting base (7) and the rear sliding ring (8) can move together in the axial direction; the front adjusting base (7) and the rear slip ring (8) can mutually rotate around the axis;
the front adjusting base (7) and the rear adjusting base (9) are respectively provided with an adjusting push rod mounting hole;
a plurality of second through holes are formed in the rear propeller hub (10), and the second through holes are used for installing rear paddles (6);
a plurality of rear guide rod mounting holes are formed in a plane, perpendicular to the axis, of the rear propeller hub (10);
the rear hub (10) is connected with the second rotating shaft (14) in a key way;
the motor bracket (12) is used for installing a servo motor;
a third through hole is formed in the end face of the motor support (12), the third through hole is matched with a guide sleeve (22), and the guide sleeve (22) is matched with a guide rod (21) arranged on the adjusting seat, so that the main adjusting seat (1) can only slide along the axial direction;
the front guide rod (15) passes through a front guide rod mounting hole on the front propeller hub (4) and then is connected with the front adjusting base (7), and the other end of the front guide rod is connected with the front slip ring (2);
one end of the rear guide rod (16) passes through a rear guide rod mounting hole on the rear propeller hub (10) and then is connected with the rear adjustment base (9), and the other end of the rear guide rod is connected with the rear slip ring (8);
the variable pitch sleeve (17) is connected with the adjusting push rod (19) through a pin shaft, and the pin shaft is prevented from falling off by a clamping ring;
the variable pitch sleeve (17) is fixedly connected with the front blade (5) and the rear blade (6) through cylindrical pins (18);
one end of the adjusting push rod (19) passes through adjusting push rod mounting holes on the front adjusting base (7) and the rear adjusting base (9) and is connected with the front adjusting base (7) and the rear adjusting base (9) through threaded pins; the other end of the adjusting push rod (19) is connected with a variable pitch sleeve in the front blade (5) and the rear blade (6);
the limiting steel sleeve (20) is respectively arranged between the front blade (5), the rear blade (6) and the variable pitch sleeve, and the outer part of the limiting steel sleeve (20) is in contact with the circular plane of the inner surfaces of the front hub (4) and the rear hub (10) for preventing the blades from falling off.
2. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: when the adjusting device works, the servo motor drives the screw rod to rotate, so that the main adjusting seat (1) moves, and then the front adjusting base (7) and the rear adjusting base (9) synchronously move, and the front blades (5) and the rear blades (6) on the front propeller hub (4) and the rear propeller hub (10) synchronously rotate.
3. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: the outer cylindrical surface of the front propeller hub (4) is uniformly provided with a plurality of blade assembly mounting holes with the same size along the circumference, namely first through holes;
the outer cylindrical surface of the rear hub (10) is uniformly provided with a plurality of blade mounting holes with the same size along the circumference, namely second through holes.
4. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: the spline housing (11) is also included;
the spline housing (11) is fixed with the front propeller hub (4), the internal spline of the spline housing (11) is matched with the external spline of the first rotating shaft (13), so that the front propeller hub (4) and the first rotating shaft (13) are limited to rotate circumferentially, and the axial directions of the front propeller hub (4) and the first rotating shaft (13) are limited through the clamping ring;
the front propeller hub (4) is connected with the second rotating shaft (14) through a bearing, and the bearing plays a supporting role;
the rear hub (10) is matched with an external spline on the second rotating shaft (14) through the internal spline; the internal spline is used for limiting the mutual rotation of the rear hub (10) and the second rotating shaft (14);
a shaft sleeve is arranged between the front propeller hub (4) and the rear propeller hub (10), and a lock nut is arranged at the tail part of the second rotating shaft to limit the axial position of the rear propeller hub; one side of the shaft sleeve is contacted with the end face of the inner ring of the bearing for supporting the front propeller hub, the other side of the shaft sleeve is contacted with the inner end face of the rear propeller hub, and the front propeller hub (4) and the rear propeller hub (10) are not interfered with each other.
5. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: two ends of the rear guide rod (16) are respectively connected with the rear sliding ring (8) and the rear adjusting base (9) and are fixedly connected through an inner hexagon screw and a hexagon nut.
6. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: the elastic retainer ring is also included;
and the elastic retainer ring limits the axial direction of the rolling bearing.
7. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: the shape of the adjusting push rod mounting hole comprises a straight-edge ellipse.
8. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: one end of the adjusting push rod (9) is connected with the front adjusting base (7) and the rear adjusting base (9) through a threaded pin, and the other end of the adjusting push rod is connected with a variable pitch sleeve (17) on the front blade assembly through a pin shaft and a clamping ring.
9. A single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to claim 1, characterized in that: the first through holes and the second through holes are uniformly distributed in the circumferential direction.
10. Method of use of a single drive pitch synchronous adjustment device for coaxial contra-rotating propeller aircraft according to any one of claims 1 to 9, characterized in that it comprises the following steps:
1) Measuring and obtaining the initial angle theta of the front blade (5) and the rear blade (6) 1 Length l of pitch sleeve (17) 1 Adjusting the length l of the push rod (19) 2 ；
2) Determining a desired adjusted blade angle θ 2 ；
3) The distance between the rotating shaft axis of the front blade (5) and the rotating shaft axis of the rear blade (6) and the rotating shaft axis of the rear blade (9) are calculated, namely:
wherein x is 1 For the distance before adjustment; x is x 2 Is the adjusted distance;
3) Calculating the movement distance L of the pre-adjustment base (7) 1 And a rear adjustment base (9) for moving distance L 2 The method comprises the following steps:
L 1 ＝L 2 ＝x 2 -x 1 (3)
4) Calculating the number of turns n of the servo motor, namely:
wherein p is the lead of the lead screw; distance l=l 1 ＝L 2 ；
5) The servo motor is controlled to rotate according to the number of turns n of the servo motor, so that the main adjusting seat (1) moves, the front adjusting base (7) and the rear adjusting base (9) move synchronously, and the front blades (5) and the rear blades (6) on the front propeller hub (4) and the rear propeller hub (10) rotate synchronously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211347721.0A CN116080896A (en) | 2022-10-31 | 2022-10-31 | Single-drive pitch synchronous adjusting device and method for coaxial contra-rotating propeller aircraft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211347721.0A CN116080896A (en) | 2022-10-31 | 2022-10-31 | Single-drive pitch synchronous adjusting device and method for coaxial contra-rotating propeller aircraft |
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| CN116080896A true CN116080896A (en) | 2023-05-09 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116576152A (en) * | 2023-07-12 | 2023-08-11 | 中国空气动力研究与发展中心低速空气动力研究所 | Wind tunnel fan blade fixing device and wind tunnel fan with adjustable blade mounting angle |
-
2022
- 2022-10-31 CN CN202211347721.0A patent/CN116080896A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116576152A (en) * | 2023-07-12 | 2023-08-11 | 中国空气动力研究与发展中心低速空气动力研究所 | Wind tunnel fan blade fixing device and wind tunnel fan with adjustable blade mounting angle |
| CN116576152B (en) * | 2023-07-12 | 2023-09-22 | 中国空气动力研究与发展中心低速空气动力研究所 | Wind tunnel fan blade fixing device and wind tunnel fan with adjustable blade mounting angle |
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