CN104908941A - Rotor wing distance adjusting structure of helicopter test bed and upper rotor wing assembly - Google Patents

Abstract

The invention relates to the technical field of aeromechanical testing, in particular to a helicopter test bench rotor pitch adjustment structure and an upper rotor assembly. The structure includes an upper propeller hub, a positioning key and a limit pin. The inner wall of the upper propeller hub mounting hole is provided with an axial sliding keyway. When installing to the inner shaft, the positioning key enters the axial sliding keyway from the axial direction, and then according to the required rotor pitch, the positioning key is screwed into the circumferential positioning keyway on the side of the axial sliding keyway, and the positioning key is axially limited , and then insert the limit pin into the axial sliding keyway, so that the positioning key is limited in the circumferential direction, and then the upper propeller hub and the upper rotor are fixedly installed and locked when rotating. During this installation process, the inner shaft A plurality of positioning keys on the outer wall can be respectively matched with circumferential positioning key grooves, and the distance between the rotors can be adjusted according to actual needs, which is beneficial to the research of the aerodynamic performance of the helicopter.

Description

A helicopter test bench rotor pitch adjustment structure and upper rotor assembly

technical field

The invention relates to the technical field of aeromechanical testing, in particular to a helicopter test bench rotor pitch adjustment structure and an upper rotor assembly.

Background technique

There is complex aerodynamic interference between the upper and lower rotors of the coaxial helicopter, and the dual-rotor system has strong kinematic and aerodynamic coupling, so it is difficult to carry out accurate mathematical modeling and calculation analysis on it. The station has a unique advantage in the study of the aerodynamic interference of the upper and lower rotors of the coaxial helicopter.

The distance between the upper and lower rotors is one of the important parameters affecting the aerodynamic characteristics of the coaxial helicopter. The distance between the upper and lower rotors directly affects the induced velocities of the two rotors on the plane of the upper and lower paddle discs, and further affects the mutual induced power loss of the two rotors. Theoretically, an appropriate distance between the upper and lower rotors can effectively reduce the mutual induced power loss of the upper and lower rotors when the coaxial helicopter is hovering or flying forward, thereby improving the aerodynamic performance. In addition, for articulated rotors, if the distance between the upper and lower rotors is too small, it will easily cause the problem of "paddling" that may occur in certain flight conditions, but if the distance between the upper and lower rotors is too large, the space size and structural quality of the rotor will increase, and at the same time, it will waste the drag when flying forward. also increases. By adjusting the distance between the upper and lower rotors on the test bench and studying the aerodynamic performance of the upper and lower rotors under different distances, the most reasonable distance between the upper and lower rotors can be found.

At present, after the installation of the coaxial helicopter test bench is completed, the distance between the upper and lower rotors is fixed, which is not conducive to the study of the aerodynamic performance of the coaxial helicopter under different rotor distances, and because there are many mechanical and electrical units at the hub of the lower rotor, The available space is small, and the position adjustment of the lower rotor is difficult.

Therefore, in view of the above deficiencies, it is necessary to provide a helicopter test bench rotor pitch adjustment structure and an upper rotor assembly with an adjustable pitch.

Contents of the invention

(1) Technical problems to be solved

The object of the present invention is to provide a helicopter test bench rotor pitch adjustment structure and upper rotor assembly with adjustable pitch to solve the problem that the unadjustable upper and lower rotor pitch of the coaxial helicopter test bench is not conducive to the research of helicopter aerodynamic performance.

(2) Technical solutions

In order to solve the above technical problems, the present invention provides a helicopter test bench rotor pitch adjustment structure, which is characterized in that: it includes an upper propeller hub, a positioning key and a limit pin, and the upper propeller hub has a mounting hole matched with the inner shaft , a plurality of positioning keys are sequentially connected to the outer wall of the inner shaft from top to bottom, and an axial sliding keyway is provided on the inner wall of the mounting hole. When the upper propeller hub is installed on the inner shaft, the axial sliding keyway and the positioning key slide up and down to cooperate; The side of the axial sliding keyway is provided with a circumferential positioning keyway matched with at least one positioning key. After the positioning key is screwed into the circumferential positioning keyway from the axial sliding keyway, it cooperates with the circumferential positioning keyway. , the limit pin is set in the axial sliding keyway, and limits the circumferential angular displacement between the inner shaft and the upper propeller hub.

Wherein, the axial sliding key groove is an axial through groove.

Wherein, a plurality of circumferential positioning key grooves are arranged on the side of the axial sliding key groove from top to bottom, and each circumferential positioning key groove corresponds to a positioning key.

Wherein, the axial sliding key groove is arc-shaped.

Wherein, the positioning key is arc-shaped, and the circumferential positioning key groove and the axial sliding key groove have an angle in the circumferential direction.

Wherein, the positioning keys on the multiple inner shafts form a row from top to bottom, and multiple rows of positioning keys are arranged on the inner shafts; correspondingly, multiple rows of circumferential positioning key grooves are provided on the inner wall of the mounting hole.

Another aspect of the present invention provides an upper rotor assembly on a helicopter test bench, including an upper rotor, an inner shaft, an upper pitch-changing pull rod, an upper tilter rotating ring, an upper tilter non-rotating ring, and the above-mentioned rotor pitch adjustment structure; In the circumferential direction of the upper hub, the rotating ring of the upper tilter is located on the inner side of the non-rotating ring of the upper tilter, and is installed on the inner shaft; the two ends of the upper pitch change rod are respectively hinged with the upper hub and the rotating ring of the upper tilter.

(3) Beneficial effects

The above-mentioned technical scheme of the present invention has the following advantages: in the helicopter test bench rotor pitch adjustment structure and the upper rotor assembly provided by the present invention, an axial sliding keyway is set on the inner wall of the upper propeller hub mounting hole, and a plurality of positioning elements arranged on the outer wall of the inner shaft The key and the axial sliding keyway slide up and down. When the upper propeller hub is installed toward the inner shaft, the positioning key enters the axial sliding keyway from the axial direction, and then according to the required rotor pitch, the positioning key is screwed into the side of the axial sliding keyway. Circumferential positioning keyway, axially limit the positioning key, and then insert the limit pin into the axial sliding keyway, so that the circumferential positioning of the positioning key is performed, thereby realizing the fixed installation and rotation of the upper propeller hub and upper rotor In the locked state, during the installation process, multiple positioning keys on the outer wall of the inner shaft can be respectively matched with the circumferential positioning key grooves, and the rotor spacing can be adjusted according to actual needs, which is beneficial to the research of the aerodynamic performance of the helicopter.

Description of drawings

Fig. 1 is a structural diagram of an upper propeller hub in Embodiment 1 of the present invention;

Fig. 2 is a structural diagram of the upper end of the inner shaft in the rotor pitch adjustment structure of the helicopter test bench according to the embodiment of the present invention;

Fig. 3 is a structural diagram of the limit pin in the rotor pitch adjustment structure of the helicopter test bench according to the embodiment of the present invention;

Fig. 4 is a three-dimensional view of the rotor pitch adjustment structure of the helicopter test bench according to the embodiment of the present invention;

Fig. 5 is a top view of the assembly of the sizing hub and the upper end of the inner shaft in Embodiment 1 of the present invention;

Fig. 6 is A-A sectional view of Fig. 5;

Fig. 7 is a structural diagram of the rotor assembly on the test bench of the two-rotor helicopter according to the embodiment of the present invention.

In the figure: 1: upper propeller hub; 2: upper end of inner shaft; 3: upper pitch change rod; 4: upper automatic tilter rotating ring; 5: upper tilter non-rotating ring; 6: collective pitch rod; 7: lower propeller Hub; 8: Rotating ring of down tilter; 9: Non-rotating ring of down tilter; 10: Outer shaft sleeve; 11: Outer shaft; 12: Inner shaft; 13: Limit pin; 14: Lower pitch rod; 101 : axial sliding keyway; 102: circumferential positioning keyway; 201: positioning key.

Detailed ways

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

Embodiment one

As shown in Figures 1-6, a helicopter test bench rotor pitch adjustment structure provided by the embodiment of the present invention includes an upper propeller hub 1, a positioning key 201 and a limit pin 13. In the installation hole, a plurality of positioning keys 201 are sequentially connected on the outer wall of the inner shaft 12 from top to bottom, and the inner wall of the installation hole is provided with an axial sliding keyway 101. When the upper propeller hub 1 is installed on the inner shaft 12, the axial sliding keyway 101 slides up and down with the positioning key 201; the side of the axial sliding keyway 101 is provided with a circumferential positioning keyway 102 matched with at least one positioning key 201, and the positioning key 201 is screwed into the circumferential positioning keyway 102 by the axial sliding keyway 101 Finally, it cooperates with the circumferential positioning keyway 102. When the helicopter test bench is working, the limit pin 13 is arranged in the axial sliding keyway 101 to limit the circumferential angular displacement between the inner shaft 12 and the upper propeller hub 1, and prevent the upper rotor from appearing when it rotates. reversal phenomenon.

Wherein, as shown in Figure 3, the positioning key 201 is complementary to the above-mentioned axial sliding keyway 101 and the circumferential positioning keyway 102, and its function is to bear the axial force generated by the torque of the inner shaft 12 and the upper rotor; the positioning key 201 is installed When adjusting the axial height of the propeller hub 1 or the upper propeller hub 1, it can slide up and down in the above-mentioned axial sliding keyway 101, so that the upper propeller hub 1 has the axial degree of freedom of the inner shaft 12 and plays the role of adjusting the distance. When the table is working, it is embedded in the above-mentioned circumferential positioning keyway 102 to bear the load, and at the same time, the upper propeller hub 1 is positioned at a certain position of the inner shaft 12 .

In the above embodiment, an axial sliding keyway 101 is provided on the inner wall of the mounting hole of the upper propeller hub 1, and a plurality of positioning keys 201 provided on the outer wall of the inner shaft 12 slide and cooperate with the axial sliding keyway 101 up and down, and the upper propeller hub 1 moves toward the inner shaft. 12 When installing, the positioning key 201 enters the axial sliding keyway 101 from the axial direction, and then according to the required rotor pitch, the positioning key 201 is screwed into the circumferential positioning keyway 102 on the side of the axial sliding keyway 101, and the positioning key 201 is adjusted. Axially limit, and then insert the limit pin 13 into the axial sliding keyway 101, so that the positioning key 201 is limited in the circumferential direction, and then the upper propeller hub 1 and the upper rotor are fixed and installed and locked when rotating , during this installation process, a plurality of positioning keys 201 on the outer wall of the inner shaft 12 can cooperate with the circumferential positioning key grooves 102 respectively, and the rotor pitch can be adjusted according to actual needs, which is beneficial to the research of the aerodynamic performance of the helicopter.

Further, as shown in Figure 2, the axial sliding keyway 101 is an axial through groove, and when the test bench is not working, the positioning key 201 on the inner shaft 12 can slide up and down in the through groove, thereby greatly changing the upper propeller hub 1 The upper and lower positions on the inner shaft 12.

Specifically, the axial sliding keyway 101 is arc-shaped, and the positioning key 201 is arc-shaped. The arc-shaped structural design is more in line with the mechanical characteristics of the two; The positioning key 201 of the shaft 12 forms a geometric complement. When the test bench is working, the circumferential positioning keyway 102 can limit the position of the positioning key 201 of the inner shaft 12 in the axial and circumferential directions, and play a role in fixing the upper propeller hub 1 .

Preferably, as shown in FIG. 4 , a plurality of circumferential positioning keyways 102 are provided from top to bottom on the side of the axial sliding keyway 101, and each positioning key 201 cooperates with the corresponding circumferential positioning keyway 102, which can improve the upper The stability of the cooperation between the propeller hub 1 and the inner shaft 12.

Further, the positioning keys 201 on the plurality of inner shafts 12 form a row from top to bottom, and four rows of positioning keys 201 are arranged on the inner shaft 12. Correspondingly, four rows of circumferential keys are also arranged on the inner wall of the mounting hole of the upper hub 1. Locate the key grooves 102 and the four axial sliding key grooves 101; in this way, the stability of the cooperation between the upper propeller hub 1 and the inner shaft 12 can be further improved.

According to the foregoing embodiments, the functions of the key parts are as follows:

Circumferential positioning key groove 102: the circumferential positioning key groove 102 and the positioning key 201 of the inner shaft 12 form a geometric complementarity. When the test bench is working, the circumferential positioning keyway 102 can limit the position of the positioning key 201 of the inner shaft 12 in the axial and circumferential directions, and play a role in fixing the upper propeller hub 1 .

Positioning key 201 of the inner shaft 12: The positioning key 201 of the inner shaft 12 is a key distributed on the outer wall of the inner shaft 12, and its shape is complementary to the above-mentioned axial sliding keyway 101 and circumferential positioning keyway 102, and its function is to bear the torque of the inner shaft 12 and the upper The axial force generated by the rotor; the positioning key 201 of the inner shaft 12 can slide up and down in the above-mentioned axial sliding keyway 101 when the upper propeller hub 1 is installed or the axial height of the upper propeller hub 1 is adjusted, so as to adjust the distance. When the test bench is working, the above-mentioned circumferential positioning keyway 102 is embedded to bear the load.

Limit pin 13: When the test bench is working, the limit pin 13 is inserted into the above-mentioned axial sliding keyway 101 to limit the circumferential angular displacement between the inner shaft 12 and the upper propeller hub 1, and prevent the upper rotor from reversing when it rotates.

The concrete operation of this embodiment is as follows:

As shown in Figure 4, Figure 5 and Figure 6, when the test bench is not working, the upper propeller hub 1 is rotated counterclockwise (viewed from the top) at a certain angle (the angle is determined by the designed keyway angle), and the inner shaft 12 The positioning key 201 enters the axial sliding keyway 101. At this time, the upper propeller hub 1 has an axial degree of freedom, and the distance between the upper and lower rotors can be adjusted arbitrarily along the inner shaft 12 within a certain range; after adjusting the distance between the upper and lower rotors, the upper propeller hub 1 Rotate clockwise (from top to bottom) by the same angle as above, so that the positioning key 201 of the inner shaft 12 enters the circumferential positioning key groove 102. As shown in Figure 1, when the positioning key 201 of the inner shaft 12 is connected with the circumferential positioning key groove 102, the axial degree of freedom and the counterclockwise (viewed from top to bottom) rotational degree of freedom of the positioning key 201 of the inner shaft 12 are restricted, only It has a clockwise (viewed from top to bottom) rotation degree of freedom, so when the inner shaft 12 rotates counterclockwise (viewed from top to bottom), it can drive the upper propeller hub 1 to rotate counterclockwise (viewed from top to bottom) sports.

When the test bench is actually working, it is possible that the positioning key 201 of the inner shaft 12 is reversed relative to the upper hub 1 and enters the axial sliding keyway 101. In order to prevent this phenomenon, a As shown in Figure 3, the limit pin 13 is used to limit the clockwise (from top to bottom) degree of freedom of the positioning key 201 of the inner shaft 12. With the function of the limit pin 13, the upper propeller hub 1 is fixed on the inner shaft 12 to ensure that the test bench can work normally. In addition, after adjusting the position of the upper propeller hub 1 on the inner shaft 12, it is necessary to replace the upper pitch-variable tie rod 3 of the corresponding length to ensure the normal function of the pitch-variable control.

Embodiment two

As shown in Figure 7, the rotor assembly on the helicopter test stand provided by the present invention includes an upper rotor, an inner shaft 12, an upper pitch-changing pull rod 3, an upper tilter rotating ring 4, an upper tilter non-rotating ring 5 and the embodiment A described rotor pitch adjustment structure; the upper rotor is installed in the circumferential direction of the upper propeller hub 1, the upper tilter rotating ring 4 is located on the inner side of the upper tilter non-rotating ring 5, and is installed on the inner shaft 12; the upper pitch The two ends of the pull rod 3 are respectively hinged with the upper propeller hub 1 and the upper tilter rotating ring.

In this embodiment, the inner shaft 12, the upper propeller hub 1, the upper pitch-changing rod 3, and the upper tilter rotating ring 4 rotate coaxially; the corresponding lower rotor connection structure (including the outer shaft 11, the lower propeller hub 7, the lower pitch-changing Tie rod 14, collective distance pull rod 6, down tilter rotating ring 8) are reversed coaxially, the down tilting device rotating ring 8 is located inside the lower tilting device non-rotating ring 9, and the lower tilting device non-rotating ring 9 is connected to the outer shaft through a ball joint on the sleeve 10; wherein, the upper rotor is connected to the upper end 2 of the inner shaft through the spacing adjustment structure of the first embodiment.

Since the upper and lower rotors of the coaxial helicopter test bench are in the state of coaxial inversion during work, and the upper rotor and the rotating ring of the upper tilter are connected by the length-adjustable upper pitch-variable tie rod 3, therefore, in the working state The rotor spacing cannot be adjusted; but the present invention can adjust the rotor spacing through the rotor spacing adjustment structure before work, so that the test bench can work under different rotor spacing conditions, and the rotor spacing can also affect the aerodynamic performance of the coaxial helicopter. Research.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, some improvements and modifications can also be made, these improvements and modifications It should also be regarded as the protection scope of the present invention.

Claims (7)

1. a helicopter test cell rotor spacing adjustment structure, it is characterized in that: it comprises propeller hub, positioning key and locating dowel pin, described upper propeller hub has the mounting hole coordinated with interior axle, multiple positioning key is connected in turn on interior axle outer wall from top to bottom, the inwall of mounting hole offers the keyway that slides axially, when the inside axle of upper propeller hub is installed, the keyway that slides axially slides up and down with positioning key and coordinates; The side of keyway of sliding axially offers the circumferential positioning spline matched with at least one positioning key, after positioning key screws in circumferential positioning spline by the keyway that slides axially, match with circumferential positioning spline, during the work of helicopter test cell, locating dowel pin is arranged on and slides axially in keyway, the circumferential angular transposition of axle and upper propeller hub in limiting.

2. helicopter test cell rotor spacing adjustment structure according to claim 1, is characterized in that: described in the keyway that slides axially be axial pass trough.

3. helicopter test cell rotor spacing adjustment structure according to claim 1, is characterized in that: the slide axially side of keyway of described circumferential positioning spline is set to multiple from top to bottom, the corresponding positioning key of each circumferential positioning spline.

4. helicopter test cell rotor spacing adjustment structure according to claim 1, is characterized in that: described in the keyway that slides axially be arc.

5. helicopter test cell rotor spacing adjustment structure according to claim 4, is characterized in that: described positioning key is arc, and described circumferential positioning spline has angle with the keyway that slides axially in circumference.

6. helicopter test cell rotor spacing adjustment structure according to claim 3, is characterized in that: shape is in a row from top to bottom for the positioning key on multiple interior axle, interior axle is arranged many registration key; Mounting hole inwall is correspondingly offered the circumferential positioning spline of many rows.

7. a rotor assemblies on helicopter test cell, is characterized in that: it comprises rotor, interior axle, upper pitch-change-link, surface thereof device swivel eye, surface thereof device non rotating ring and the rotor spacing adjustment structure described in any one of claim 1-6; Upper rotor is arranged on the circumference of propeller hub, and surface thereof device swivel eye is positioned at the inner side of surface thereof device non rotating ring, and is arranged on interior axle; The two ends of upper pitch-change-link respectively with upper propeller hub and surface thereof device swivel eye hinged.