A rotary extrusion test fixture for assessing the fatigue life of elastic rings

Abstract

The present invention relates to the technical field of aero-engines, and discloses a rotary extrusion test fixture for assessing the fatigue life of an elastic ring. By adjusting a bias adjustment mechanism, a slider applies an extrusion force to an inner ring along the radial direction of the inner ring. Since the inner ring is softly connected to a rubber tube adapter, it will produce radial displacement after being extruded by a force transmission bearing, and the extrusion force is transmitted to the elastic ring, thereby achieving extrusion of the elastic ring. In addition, when the tester fixture is working, a rotary drive mechanism drives the rotary fixture and the elastic ring to rotate together, and the slider is connected to the inner ring by a force transmission bearing. The slider does not rotate with the rotary fixture, and the contact point of the slider with the inner ring of the rotary fixture can be relatively stationary. The contact extrusion point of the elastic ring with the inner ring or the outer ring can perform circumferential motion in the rotating coordinate system of the rotary fixture, so that the elastic ring undergoes extrusion deformation in a full cycle, thereby achieving fatigue life assessment of the elastic ring under full cycle extrusion.

Description

Technical Field

[0001] The invention relates to the technical field of aviation engines and discloses a rotary extrusion test tool for assessing the fatigue life of an elastic ring. Background Art

[0002] Aircraft engine operational failures often stem from the abnormal condition of individual components. Failure of key components can severely impact engine performance, necessitating the assessment of these critical components during aircraft engine development. Elastic rings are damping elements in the rotor support structure of aircraft engines. Failure of these rings can affect the rotor's damping characteristics, leading to excessive engine vibration. Assessing the fatigue properties of elastic rings ensures smooth engine operation.

[0003] During engine rotor rotation, the bearing is subjected to unbalanced forces from the rotor, causing deformation of the elastic ring. This unbalanced force is then transmitted to the support seat through the outer wall of the elastic ring. In particular, the elastic ring is designed with staggered inner and outer bosses, making it more susceptible to deformation than the bearing outer ring and support seat.

[0004] In simplified analysis, the elastic ring is considered to be an elastically deformable body, the support seat is a fixed rigid body, and the outer ring of the bearing is an external rigid body with circular motion. The working process of the elastic ring is a process of continuous extrusion and deformation when the inner and outer rings are in contact with each other and move relative to each other; as shown in the attached figure, Figure 1 As shown, the inner circle of the inner rigid body, O2, moves in a circle with a radius of e around the outer circle of the stationary outer rigid body, O1. Figure 1 The offset e of the relative motion of the inner and outer circles is used as an indicator. The content of the fatigue life assessment test of the elastic ring 1 is that the elastic ring 1 is subjected to the extrusion deformation of the given offset e in a full circle cycle. The extrusion direction at a certain moment is Figure 1 The conventional test fixture for fatigue life assessment of the elastic ring 1 is complex in structure and difficult to adjust the bias pressure during the extrusion test of the elastic ring 1 . Summary of the Invention

[0005] The purpose of the present invention is to provide a rotary extrusion test fixture for assessing the fatigue life of an elastic ring. By adjusting the bias adjustment mechanism, the slider applies an extrusion force to the inner ring along the radial direction of the inner ring, thereby achieving extrusion of the elastic ring. During the rotation of the rotating shaft, the contact extrusion point between the elastic ring and the inner ring or the outer ring can perform circumferential motion in the rotating coordinate system of the rotary fixture, so that the elastic ring undergoes extrusion deformation in a full cycle, thereby achieving fatigue life assessment of the elastic ring under full cycle extrusion.

[0006] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0007] A rotary extrusion test fixture for assessing the fatigue life of an elastic ring comprises a rotating shaft and a rotary fixture coaxially connected to the rotating shaft, wherein the rotating shaft is mounted on a base via a bearing seat; the rotary fixture comprises a coaxially arranged inner ring and an outer ring, an elastic ring being arranged between the inner ring and the outer ring; the outer ring is coaxially connected to the rotating shaft via a rigid transition section, and the inner ring is coaxially connected to the rotating shaft via a flexible tube; and further comprises a bias adjustment mechanism, wherein a slider is mounted on the bias adjustment mechanism, and the slider is coaxially rotatably connected to the inner ring via a force transmission bearing, and the bias adjustment mechanism is used to apply an extrusion force along the radial direction of the elastic ring to the elastic ring via the slider and the inner ring.

[0008] Furthermore, an inner boss is provided on the inner wall of the elastic ring, and an outer boss is provided on the outer wall of the elastic ring. The inner boss and the outer boss of the elastic ring are staggered in the circumferential direction.

[0009] Furthermore, the inner boss contacts the outer wall of the inner ring, the outer boss contacts the inner wall of the outer ring, and an anti-rotation key is provided between the elastic ring and the outer ring to prevent the elastic ring from rotating relative to the outer ring.

[0010] Furthermore, a biasing wheel is provided between the outer wall of the force transmission bearing and the inner wall of the inner sleeve ring.

[0011] Furthermore, the bias adjustment mechanism includes a base plate, a top plate is fixed directly above the base plate, a guide rod is fixed between the top plate and the base plate, the slider is located between the top plate and the base plate, and a guide hole is provided on the slider for cooperating with the guide rod; a threaded hole parallel to the guide rod is provided on the slider, an adjusting bolt is provided in the threaded hole, and the bottom of the adjusting bolt is in contact with the upper surface of the base plate.

[0012] Furthermore, the adjusting bolt extends out of the upper surface of the top plate, and the end of the adjusting bolt located on the upper surface of the top plate is provided with a rotating handle, the top plate is provided with a scale, and the rotating handle of the adjusting bolt is provided with a pointer assembly that cooperates with the scale.

[0013] Furthermore, the flexible tube is a rubber tube, the inner wall of the flexible tube is connected to the outer wall of the rotating shaft by an interference fit, and the inner wall of the flexible tube is connected to the outer wall of the inner ring by an interference fit.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention adjusts the bias adjustment mechanism so that the slider applies an extrusion force to the inner ring along the radial direction of the inner ring, thereby achieving extrusion of the elastic ring; during the rotation of the rotating shaft, the contact extrusion point between the elastic ring and the inner ring or the outer ring can perform circumferential motion in the rotating coordinate system of the rotating tooling, so that the elastic ring is subjected to extrusion deformation in a full cycle, thereby achieving fatigue life assessment of the elastic ring under full cycle extrusion. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the extrusion deformation of the elastic ring during operation;

[0017] Figure 2 Schematic diagram of the rotary extrusion test fixture structure in the embodiment;

[0018] Figure 3 This is a schematic diagram of the installation structure of the rotary extrusion test fixture for performing fatigue life assessment of the elastic ring in the embodiment;

[0019] Among them, 1. elastic ring; 2. rotating tooling; 3. rotating shaft; 4. bearing seat; 5. inner ring; 6. outer ring; 7. rigid transition section; 8. flexible tube; 9. slider; 10. force transmission bearing; 11. inner boss; 12. outer boss; 13. anti-rotation key; 14. biasing wheel; 15. bottom plate; 16. top plate; 17. guide rod; 18. adjusting bolt; 19. rotating handle; 20. rotating drive mechanism. DETAILED DESCRIPTION

[0020] The present invention will be described in further detail below with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the present invention to the following embodiments, as all technologies implemented based on the present invention fall within the scope of the present invention.

[0021] Example

[0022] See also Figure 1-Figure 3 , a rotary extrusion test fixture for assessing the fatigue life of an elastic ring, comprising a rotating shaft 3 and a rotating fixture 2 coaxially connected to the rotating shaft 3, the rotating shaft 3 being mounted on a base through a bearing seat 4; the rotating fixture 2 comprises a coaxially arranged inner ring 5 and an outer ring 6, an elastic ring 1 being arranged between the inner ring 5 and the outer ring 6; the outer ring 6 is coaxially connected to the rotating shaft 3 through a rigid transition section 7, and the inner ring 5 is coaxially connected to the rotating shaft 3 through a flexible tube 8; and further comprising a bias adjustment mechanism, on which a slider 9 is mounted, the slider 9 being coaxially rotatably connected to the inner ring 5 through a force transmission bearing 10, the bias adjustment mechanism being used to apply an extrusion force radially along the elastic ring 1 to the elastic ring 1 through the slider 9 and the inner ring 5.

[0023] In this embodiment, when fatigue life assessment of the elastic ring 1 is required, one end of the rotating shaft 3 is connected to a rotary drive mechanism 20 (e.g., a motor), which drives the rotating shaft 3. The rotating shaft 3 is connected to the outer collar 6 via a rigid connection section, ensuring that the outer collar 6's axial, radial, and circumferential motion is synchronized with that of the rotating shaft 3. The rotating shaft 3 is connected to the inner collar 5 via a flexible tube 8. The flexible tube 8 primarily provides torsional stiffness, ensuring that the inner collar 5's circumferential motion is synchronized with that of the rotating shaft 3 and capable of transmitting radial displacement. During the rotation of the rotating shaft 3, the bias adjustment mechanism is adjusted to enable the slider 9 to apply an extrusion force to the inner ring 5 along the radial direction of the inner ring 5. Since the inner ring 5 is connected to the rubber tube soft connection, it will produce a radial displacement e after being squeezed by the force transmission bearing 10, and the extrusion force is transmitted to the elastic ring 1, thereby squeezing the elastic ring 1; in addition, when the tester tooling is working, the rotation drive mechanism 20 drives the rotating tooling 2 and the elastic ring 1 to rotate together, and the slider 9 and the inner ring 5 are connected by the force transmission bearing 10. The slider 9 will not rotate with the rotating tooling 2, and the contact point between the slider 9 and the inner ring 5 of the rotating tooling 2 can be relatively stationary; while the contact extrusion point between the elastic ring 1 and the inner ring 5 or the outer ring 6 can perform circumferential motion in the rotating coordinate system of the rotating tooling 2, so that the elastic ring 1 undergoes extrusion deformation in a full cycle, thereby realizing fatigue life assessment of the elastic ring 1 under cyclic extrusion in a full cycle.

[0024] The inner boss 11 contacts the outer wall of the inner ring 5, and the outer boss 12 contacts the inner wall of the outer ring 6. The rotary extrusion test fixture in this embodiment can also set an anti-rotation key 13 between the elastic ring 1 and the outer ring 6 to prevent the elastic ring 1 from rotating relative to the outer ring 6, thereby realizing synchronous rotation between the elastic ring 1 and the outer ring 6 during rotation, so that the contact extrusion point between the elastic ring 1 and the inner ring 5 can move circumferentially in the rotating coordinate system of the rotary fixture 2, so that the elastic ring 1 is subjected to the extrusion effect from the inner ring 5 in a full cycle, thereby realizing fatigue life assessment of the elastic ring 1 under full cycle extrusion when the elastic ring 1 and the outer ring 6 are relatively fixed.

[0025] In this embodiment, a biasing wheel 14 is arranged between the outer wall of the force transmission bearing 10 and the inner wall of the inner ring 5 to ensure the transmission of the extrusion force between the force transmission bearing 10 and the inner ring 5, and to avoid direct contact between the outer wall of the force transmission bearing 10 and the inner wall of the inner ring 5, thereby reducing the wear of the outer wall of the force transmission bearing 10 and extending the service life of the force transmission bearing 10.

[0026] The bias adjustment mechanism of the present invention is an adjustment mechanism that can be adjusted to cause the slider 9 to move radially, thereby exerting an extrusion effect on the inner collar 5, such as a hydraulic rod or a threaded torque loading mechanism. This embodiment provides a schematic diagram of a bias adjustment mechanism using a threaded torque loading mechanism, comprising a base plate 15, a top plate 16 fixed directly above the base plate 15, a guide rod 17 fixed between the top plate 16 and the base plate 15, the slider 9 positioned between the top plate 16 and the base plate 15, and a guide hole provided in the slider 9 for engaging with the guide rod 17. The slider 9 is provided with a threaded hole parallel to the guide rod 17, and an adjustment bolt 18 is provided in the threaded hole, the bottom of which contacts the upper surface of the base plate 15. By rotating the adjustment bolt 18, the slider 9 is displaced along the axial direction of the adjustment bolt 18, thereby adjusting and limiting the offset of the slider 9 and ensuring that the extrusion force is stable and not easily changed.

[0027] The adjusting bolt 18 extends out of the upper surface of the top plate 16, and a rotating handle 19 is provided at the end of the adjusting bolt 18 located on the upper surface of the top plate 16. A scale is provided on the top plate 16, and a pointer assembly that cooperates with the scale is provided on the rotating handle 19 of the adjusting bolt 18, so that the adjusting bolt 18 can be rotated conveniently by rotating the rotating handle 19, and the precise control of the offset of the inner ring 5 of the rotary extrusion test fixture can be achieved through the pointer assembly and the scale display.

[0028] The flexible tube 8 in this embodiment is a rubber tube, and the inner wall of the flexible tube 8 is connected to the outer wall of the rotating shaft 3 by an interference fit. The inner wall of the flexible tube 8 is connected to the outer wall of the inner ring 5 by an interference fit, ensuring that the stiffness in the torsional direction of the rotating shaft 3 can be normally transmitted to the inner ring 5, thereby driving the inner ring 5 to rotate, and generating a periodic cyclic extrusion effect on the elastic ring 1.

[0029] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A rotary extrusion test fixture for assessing the fatigue life of an elastic ring, characterized in that: The invention relates to a rotary tool (2) comprising a rotating shaft (3) and a rotating tool (2) coaxially connected to the rotating shaft (3), wherein the rotating shaft (3) is mounted on a base via a bearing seat (4); the rotating tool (2) comprises a coaxially arranged inner ring (5) and an outer ring (6), wherein an elastic ring (1) is arranged between the inner ring (5) and the outer ring (6); the outer ring (6) is coaxially connected to the rotating shaft (3) via a rigid transition section (7), and the inner ring (5) is coaxially connected to the rotating shaft (3) via a flexible tube (8); and the invention also comprises a bias adjustment mechanism, wherein a slider (9) is mounted on the bias adjustment mechanism, and the slider (9) is coaxially rotatably connected to the inner ring (5) via a force transmission bearing (10), and the bias adjustment mechanism is used to adjust the bias pressure to the inner ring (5) via the slider (9) and the inner ring (5). The elastic ring (1) applies an extrusion force in the radial direction of the elastic ring (1); the bias adjustment mechanism includes a bottom plate (15), a top plate (16) is fixed just above the bottom plate (15), a guide rod (17) is fixed between the top plate (16) and the bottom plate (15), the slider (9) is located between the top plate (16) and the bottom plate (15), and a guide hole is provided on the slider (9) to cooperate with the guide rod (17); a threaded hole parallel to the guide rod (17) is opened on the slider (9), an adjusting bolt (18) is provided in the threaded hole, and the bottom of the adjusting bolt (18) contacts the upper surface of the bottom plate (15); a bias wheel (14) is provided between the outer wall of the force transmission bearing (10) and the inner wall of the inner ring (5).

2. The rotary extrusion test fixture for assessing the fatigue life of an elastic ring according to claim 1, characterized in that: The inner wall of the elastic ring (1) is provided with an inner boss (11), and the outer wall of the elastic ring (1) is provided with an outer boss (12). The inner boss (11) and the outer boss (12) of the elastic ring (1) are staggered in the circumferential direction.

3. The rotary extrusion test fixture for evaluating the fatigue life of an elastic ring according to claim 2, characterized in that: The inner boss (11) contacts the outer wall of the inner ring (5), the outer boss (12) contacts the inner wall of the outer ring (6), and an anti-rotation key (13) is provided between the elastic ring (1) and the outer ring (6) to prevent the elastic ring (1) from rotating relative to the outer ring (6).

4. The rotary extrusion test fixture for evaluating the fatigue life of an elastic ring according to claim 1, characterized in that: The adjusting bolt (18) extends out of the upper surface of the top plate (16), and a rotating handle (19) is provided at the end of the adjusting bolt (18) located on the upper surface of the top plate (16). A scale is provided on the top plate (16), and a pointer assembly matching the scale is provided on the rotating handle (19) of the adjusting bolt (18).

5. The rotary extrusion test fixture for evaluating the fatigue life of an elastic ring according to claim 1, characterized in that: The flexible tube (8) is a rubber tube, and the inner wall of the flexible tube (8) is connected to the outer wall of the rotating shaft (3) by an interference fit, and the inner wall of the flexible tube (8) is connected to the outer wall of the inner ring (5) by an interference fit.

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