Aero-engine blade exhaust edge in-situ self-adaptive eddy current detection probe

Abstract

The invention relates to the technical field of nondestructive testing, and discloses an aero-engine blade exhaust edge in-situ self-adaptive eddy current testing probe which comprises a handle, a probe rod and a testing end, and the testing end is composed of a first connecting seat, a universal joint mechanism, a second connecting seat and a variable-angle joint mechanism. Two clamping plates are formed at the front end of the first connecting base and used for clamping a detection gap of the exhaust edge of the blade, and a multi-channel eddy current detection sensor array is arranged on the clamping face. The universal joint mechanism adopts a ball head and ball socket structure to realize multi-degree-of-freedom self-adaptive deflection, a fastening device is arranged to keep the detection end stable, a variable-angle joint mechanism is designed to be connected with a second connecting seat and a probe rod, and the bending angle can be adjusted within the range of 0-90 degrees. Through combination of an innovative universal structure and a variable-angle joint mechanism, multi-angle free adjustment of the detection end of the probe rod is realized, and the detection end can flexibly adapt to exhaust edges of aero-engine blades with different curvatures while the handle end is kept fixed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of non-destructive testing, in particular to an in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade. BACKGROUND

[0002] Aero-engine blades work in extremely harsh environments, and the stress concentration in the exhaust edge region is the key position for fatigue crack initiation and propagation. Regular in-situ detection of this area with high sensitivity is an important means to ensure flight safety. Eddy current testing technology is widely used in this field due to its high sensitivity to surface cracks, no need for coupling agent, and fast response speed.

[0003] However, the existing in-situ eddy current detection technology for blades faces many challenges: first, the internal space of the engine casing is extremely narrow and tortuous, and the blade to be tested is usually located deep inside, requiring a long probe to reach it, and the operating field of view is severely limited. Second, the exhaust edge of the blade, especially the back side, has a complex three-dimensional curved surface with continuously changing curvature from the blade root to the blade tip. Third, existing detection tools often use articulated probes, but usually only provide a single degree of freedom for swinging, which cannot adapt to complex three-dimensional curvature changes. To complete the detection of a single blade, multiple probes with different preset angles are required, and frequent changes during the detection process result in low efficiency. Moreover, rigid probes cannot maintain a constant and optimal state of adhesion to the curved surface, and the inevitable "lift-off effect" significantly reduces the sensitivity and signal-to-noise ratio of eddy current detection, increasing the risk of missing micron-level early cracks.

[0004] Therefore, there is an urgent need in the art for a high-sensitivity eddy current detection sensor and method that can automatically adapt to complex curvature changes, complete full-size scanning with a single probe, and ensure stable adhesion. SUMMARY

[0005] To solve the above problems, the present application provides an in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade, which can realize adaptive adhesion detection in a narrow space with long distance and a wide angle range, effectively improving the detection probability and efficiency of fatigue cracks in the exhaust edge of an aero-engine blade. The present application is implemented as follows:

[0006] An in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade, comprising a handle (3), a probe rod (2) connected to the handle (3), and a detection end (1) provided at the distal end of the probe rod (2), the detection end (1) comprising:

[0007] a first connecting seat (11) rotatably connected to a second connecting seat (13) through a universal joint mechanism (12);

[0008] A variable angle joint mechanism (14) is connected between the second connecting seat (13) and the distal end of the probe rod (2), and is configured to have a bending angle adjustable and lockable within a range of 0° to 90°;

[0009] The first connecting seat (11) is composed of a first clamping plate (111) and a second clamping plate (112) arranged in parallel and spaced apart, forming a detection gap (113) for accommodating and clamping the blade exhaust edge;

[0010] The first clamping plate (111) is provided with a multi-channel eddy current detection sensor array (15) for detecting defects of the blade exhaust edge;

[0011] The universal joint mechanism (12) is used to provide multi-degree-of-freedom adaptive deflection of the first connecting seat (11) relative to the second connecting seat (13), which cooperates with the variable angle joint mechanism (14) to enable the multi-channel eddy current detection sensor array (15) to be variable angle and adaptively fitted on the aero-engine blade exhaust edge with different curvature changes during detection.

[0012] The universal joint mechanism (12) includes a ball head (121) and a ball socket (122);

[0013] The ball head (121) is arranged on the first connecting seat (11), and the ball socket (122) is arranged on the second connecting seat (13), and the ball head (121) is embedded in the ball socket (122), so that the ball head can rotate relative to the ball socket;

[0014] The universal joint mechanism (12) further includes a fastening device for providing rotational damping or locking force.

[0015] Further, the variable angle joint mechanism (14) includes a first connecting member and a second connecting member hingedly connected to each other, and a locking knob for locking the hinged angle.

[0016] Further, the multi-channel eddy current detection sensor array (15) includes an absolute eddy current detection coil and a set of differential eddy current detection coils;

[0017] The absolute eddy current detection coil is used to monitor the lift-off effect between the probe and the blade exhaust edge in real time during detection to evaluate the fitting state;

[0018] The set of differential eddy current detection coils are arranged in a direction substantially perpendicular to the blade exhaust edge, for scanning and evaluating the length and topography of the crack defects on the blade exhaust edge.

[0019] Further, the absolute eddy current detection coil and the differential eddy current detection coil are independently arranged on the first clamping plate (111), and the absolute eddy current detection coil is located outside the scanning path of the differential eddy current detection coil array.

[0020] Further, the detection end further comprises a telescopic mechanism (16) arranged between the second connecting seat (13) and the variable-angle joint mechanism (14), so that the multi-channel eddy current detection sensor array (15) can be adaptively close to, aligned with and attached to the exhaust edge of the aero-engine blade in different spatial positions, and full coverage detection of the edge of the aero-engine blade is realized.

[0021] Further, the outer sleeve (161) is fixedly connected with the variable-angle joint mechanism (14);

[0022] The inner sleeve (162) is fixedly connected with the second connecting seat (13);

[0023] The inner sleeve (162) is slidably sleeved in the outer sleeve (161);

[0024] The locking screw (163) is screwed on the outer sleeve (161), and the end portion thereof can selectively abut against the inner sleeve (162) to fix the telescopic position.

[0025] Compared with the prior art, the beneficial effects of the present application are:

[0026] The present application realizes multi-angle free adjustment of the detection end of the probe rod by combining the innovative universal structure with the variable-angle joint mechanism, while keeping the handle end fixed, so that the detection end can be flexibly conformed to the exhaust edge of the aero-engine blade with different curvatures. Specifically, the present application has the following advantages:

[0027] I. The combination of the double-angle adjustment structure enables a single probe to perfectly conform to a complex three-dimensional curved surface, realizing one-key detection without frequent replacement of the probe or adjustment of the equipment, and solving the problem that a single probe in the prior art cannot adapt to complex curved surface detection.

[0028] II. By eliminating the lifting effect fluctuation caused by the loose conformance of the probe to the curved surface, the stability and consistency of the detection signal are ensured, so that the eddy current instrument is always in the best working state, the detection capability of micron-level fatigue cracks is significantly improved, and the blank of insufficient detection accuracy in the high-curvature area in the prior art is filled.

[0029] III. The long probe rod design meets the long-distance operation requirement, the self-adaptive characteristic greatly reduces the technical requirements and operation difficulty of the operator, improves the scanning speed and coverage efficiency, and is particularly suitable for in-situ detection environment, solving the pain points of difficult adjustment and low efficiency in narrow space in the traditional method. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the examples of the present application or the prior art or the descriptions in the prior art, the drawings are briefly introduced, and obviously, for those skilled in the art, without creative labor, other drawings can also be obtained according to these drawings.

[0031] Figure 1 The overall structure schematic diagram of example one.

[0032] Figure 2 The overall structure schematic diagram of example one. Figure 1 The specific structure schematic diagram of the detection end in example one.

[0033] Figure 3 The structure schematic diagram of the first connecting seat and the second connecting seat.

[0034] Figure 4 The overall structure schematic diagram of example one. Figure 3 The explosion structure schematic diagram of example one.

[0035] Figure 5 The specific structure schematic diagram of the detection end in example two.

[0036] 1-detection end;

[0037] 2-probe rod;

[0038] 3-handle;

[0039] 11-first connecting seat, 12-gimbal mechanism, 13-second connecting seat, 14-variable angle joint mechanism, 15-multi eddy current detection sensor array;

[0040] 111-first clamping plate, 112-second clamping plate, 113-detection gap;

[0041] 121-ball head, 122-socket;

[0042] 161-outer sleeve, 162-inner sleeve, 163-locking screw. DETAILED DESCRIPTION

[0043] In order to make the purposes, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application.

[0044] Example one

[0045] The embodiment provides a miniaturized blade exhaust edge in-situ adaptive vortex detection probe suitable for narrow internal space of an aero-engine. Figures 1-4 The specific structure and implementation mode are as follows.

[0046] The probe adopts a modular design and sequentially comprises a handle 3, a probe rod 2 and a detection end 1 from a proximal end to a distal end. The probe rod 2 is an elongated rigid pipe element, the proximal end of which is fixedly connected with the handle 3, and the distal end of which is connected with the detection end 1. The detection end 1 is a core component for performing a detection function, and has a small assembly size to adapt to extreme space constraints in the engine.

[0047] The detection end 1 mainly comprises a first connecting seat 11, a universal joint mechanism 12, a second connecting seat 13 and a variable-angle joint mechanism 14.

[0048] The first connecting seat 11 is located at the distal end and directly contacts the blade exhaust edge. The first connecting seat 11 is composed of a first clamping plate 111 and a second clamping plate 112 which are arranged in parallel and at intervals, and the first clamping plate 111 and the second clamping plate 112 are integrally formed or fixedly connected through a connecting piece, and together form a detection gap 113 with an adjustable width for accommodating and clamping the blade. A multi-channel eddy current detection sensor array 15 is embedded on the inner side of the first clamping plate 111 (i.e. the side facing the detection gap 113). In the embodiment, the overall length of the first connecting seat is about 10-15 mm.

[0049] The variable-angle joint mechanism 14 is connected between the proximal end of the second connecting seat 13 and the distal end of the probe rod 2. The variable-angle joint mechanism 14 is configured to have a bending angle adjustable and lockable in a range of 0° to 90°.

[0050] The first connecting seat 11 is composed of the first clamping plate 111 and the second clamping plate 112 which are arranged in parallel and at intervals, and forms the detection gap 113 for accommodating and clamping the blade exhaust edge.

[0051] The first clamping plate 111 is provided with the multi-channel eddy current detection sensor array 15 for detecting defects of the blade exhaust edge; the first clamping plate 111 and the second clamping plate 112 can be made of a lightweight and high-rigidity material (such as an aero aluminum material or a composite material), and a flexible gasket or replaceable wear-resistant material can be embedded on the inner side, so as to not only protect the surface of the blade, but also enhance clamping stability.

[0052] The gimbal mechanism 12 is used to provide multi-degree-of-freedom adaptive deflection of the first connecting seat 11 relative to the second connecting seat 13, which cooperates with the variable-angle joint mechanism 14 to enable the multi-channel eddy current detection sensor array 15 to be variable-angle and adaptively attached to the air engine blade exhaust edge with different curvature changes during detection. The present application realizes two-degree-of-freedom adaptive deflection, and the rotation gap is precisely adjusted to ensure flexible response to changes in the blade surface and avoid detection shaking caused by looseness. Compared with the structure of the traditional probe with single-degree-of-freedom adjustment, the gimbal of the present embodiment realizes greater range and more flexible multi-directional adaptation while maintaining a small size, and can be attached to the curved surface in real time without manual intervention.

[0053] The mechanism can adopt the form of a plurality of micro hinges connected in series, and the total length can be controlled to about 3 cm, and the structure is fine and small.

[0054] Further, the gimbal mechanism 12 includes a ball head 121 and a ball socket 122; the ball head 121 is arranged on the first connecting seat 11, and the ball socket 122 is arranged on the second connecting seat 13, the ball head 121 is embedded in the ball socket 122 to form a joint pair that can rotate in all directions, so that the ball head can rotate in all directions relative to the ball socket. The diameter of the gimbal component is about 0.5 cm, and the whole is very compact. In order to realize stability and flexibility under small size, the ball head can be made of ceramic material, and the ball socket can be made of oil-containing sintered bronze or PEEK engineering plastic.

[0055] The gimbal mechanism 12 further includes a fastening device for providing rotation damping or locking force. The fastening device can be a damping element or an elastic structure with adjustable pre-tightening force, so that the probe can be flexible and adaptive when attaching to the blade surface, and can also maintain sufficient stability to avoid shaking during detection. Specifically, one or more O-rings or Teflon elastic gaskets can be arranged in the opening edge or internal ring groove of the ball socket 122. It can not only prevent dust and oil from entering the ball socket, but also provide adjustable damping force for the rotation of the ball head, avoid shaking of the probe when it is adaptively attached, and ensure the stability of the detection process. Alternatively, a micro spring array can be integrated inside the gimbal to provide a slight automatic centering torque, which helps the probe to return to the initial reference position after leaving the blade, facilitating the next positioning.

[0056] Further, the variable-angle joint mechanism 14 includes a first connecting piece and a second connecting piece that are hingedly connected to each other, and a locking knob for locking the hinged angle. In the present embodiment, the structure is realized by connecting the shaft to the shaft seat, and the shaft seat is integrally formed with the second connecting seat, and the shaft is rotatably arranged at the end of the probe rod.

[0057] In operation, the operator first adjusts and locks the variable angle joint mechanism 14 according to the position and orientation of the blade, so that the detection end 1 is roughly aligned with the target area. Then the probe is sent in, so that the blade exhaust edge enters the detection gap 113. When the blade is contacted, the gimbal mechanism 12 starts to work, allowing the first connecting seat 11 to adaptively deflect in a set angle range, so that the sensor array 15 is finally fully and stably attached to the blade surface. The double adjustment mechanism of "pre-adjustment coarse positioning + gimbal fine self-adaptation" is the key to realizing efficient and high-precision in-situ detection in extremely limited space.

[0058] Further, the multi-channel eddy current detection sensor array 15 includes an absolute eddy current detection coil and a set of differential eddy current detection coils.

[0059] The absolute eddy current detection coil is used to monitor the lift-off effect between the probe and the blade exhaust edge in real time during the detection process, so as to evaluate the attachment state. If the lift-off signal fluctuation exceeds the limit, it indicates that the attachment is poor, and the probe attitude needs to be adjusted, thereby providing a prerequisite for the effectiveness of the detection data.

[0060] The set of differential eddy current detection coils are arranged in a direction substantially perpendicular to the blade exhaust edge, and are used to scan and evaluate the length and morphology of the crack defects on the blade exhaust edge. Each eddy current detection coil can be independently excited and received, realizing full coverage scanning of the blade exhaust edge region.

[0061] Further, the absolute eddy current detection coil and the differential eddy current detection coil are independently arranged on the first clamping plate 111, and the absolute eddy current detection coil is located outside the scanning path of the differential eddy current detection coil array. Placing the absolute eddy current detection coil on one side or behind the differential coil array prevents the electromagnetic field of the absolute coil from interfering with the electromagnetic field of the differential coil during scanning, ensuring the independence of the two signals.

[0062] Embodiment Two

[0063] Referring to the accompanying drawings, Figure 5 On the basis of Embodiment One, the detection end further includes a telescopic mechanism 16 arranged between the second connecting seat 13 and the variable angle joint mechanism 14, so that the multi-channel eddy current detection sensor array 15 can adaptively approach, align and attach to the aero-engine blade exhaust edge in different spatial positions, realizing full coverage detection of the edge of the aero-engine blade exhaust edge.

[0064] Further, the telescopic structure 16 adopts a precision sleeve structure, which is specifically composed of the following components:

[0065] The outer sleeve 161 is a short tubular structure with one end closed. The closed end is rigidly fixed to the distal end of the variable angle joint mechanism 14 by screwing or welding. The axial position of the outer sleeve 161 is determined by the variable angle joint mechanism 14;

[0066] The inner sleeve 162 is a section of a slidable precision shaft, the distal end of which is rigidly fixed to the proximal end of the second connecting seat 13 by screwing or fastening;

[0067] The proximal end of the inner sleeve 162 is slidably sleeved in the inner hole of the outer sleeve 161, and the two form a set of precision sliding pairs;

[0068] A locking screw 163 is screwed radially through the wall of the outer sleeve 161. When adjusted to the desired position, the locking screw 163 is tightened, the end of which abuts against the outer wall of the inner sleeve 162, and is fixed by a large friction force to prevent accidental displacement during detection.

[0069] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade, comprising a handle (3), a probe rod (2) connected to the handle (3), and a detection end (1) disposed at the distal end of the probe rod (2), characterized in that: The detection end (1) includes: A first connecting seat (11) is rotatably connected to a second connecting seat (13) via a universal joint mechanism (12); A variable angle joint mechanism (14) is connected between the second connecting seat (13) and the distal end of the probe (2), the variable angle joint mechanism (14) being configured to have an adjustable and lockable bending angle in the range of 0° to 90°; The first connecting seat (11) is composed of a first clamping plate (111) and a second clamping plate (112) arranged in parallel and at intervals, forming a detection gap (113) for accommodating and clamping the exhaust edge of the blade; The first clamping plate (111) is provided with a multi-channel eddy current detection sensor array (15) for detecting blade exhaust edge defects; The universal joint mechanism (12) is used to provide multi-degree-of-freedom adaptive deflection of the first connecting seat (11) relative to the second connecting seat (13). It cooperates with the variable angle joint mechanism (14) to enable the multi-channel eddy current detection sensor array (15) to be able to be variably and adaptively attached to the exhaust edge of the aero-engine blade with different curvature during the detection process.

2. The in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade according to claim 1, characterized in that, The universal joint mechanism (12) includes a ball joint (121) and a ball socket (122); The ball head (121) is disposed on the first connecting seat (11), and the ball socket (122) is disposed on the second connecting seat (13). The ball head (121) is embedded in the ball socket (122), so that the ball head can rotate omnidirectionally relative to the ball socket. The universal joint mechanism (12) also includes a fastening device for providing rotational damping or locking force.

3. The in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade according to claim 1, characterized in that, The variable angle joint mechanism (14) includes a first connector and a second connector that are hinged to each other, and a locking knob for locking the hinge angle.

4. A probe for in-situ adaptive eddy current detection of the exhaust edge of an aero-engine blade according to any one of claims 1 to 3, characterized in that, The multi-channel eddy current detection sensor array (15) includes an absolute eddy current detection coil and a set of differential eddy current detection coils; The absolute eddy current detection coil is used to monitor the lift-off effect between the probe and the exhaust edge of the blade in real time during the detection process, so as to evaluate the fit status. The set of differential eddy current detection coils are arranged in a direction approximately perpendicular to the exhaust edge of the blade, and are used to scan and evaluate the length and morphology of crack defects on the exhaust edge of the blade.

5. The in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade according to claim 4, characterized in that, The absolute eddy current detection coil and the differential eddy current detection coil are arranged independently on the first clamping plate (111), and the absolute eddy current detection coil is located outside the scanning path of the differential eddy current detection coil array.

6. A probe for in-situ adaptive eddy current detection of the exhaust edge of an aero-engine blade according to any one of claims 1 to 5, characterized in that, The detection end also includes a telescopic mechanism (16) disposed between the second connecting seat (13) and the variable angle joint mechanism (14), so that the multi-channel eddy current detection sensor array (15) can adaptively approach, align and fit against the exhaust edge of the aero-engine blade at different spatial positions, so as to achieve full coverage detection of the edge of the exhaust edge of the aero-engine blade.

7. The in-situ adaptive eddy current detection probe for the exhaust edge of an aero-engine blade according to claim 6, characterized in that, The telescopic mechanism (16) includes: The outer tube (161) is fixedly connected to the variable angle joint mechanism (14); The inner sleeve (162) is fixedly connected to the second connecting seat (13); The inner sleeve (162) is slidably fitted inside the outer sleeve (161); A locking screw (163) is screwed onto the outer sleeve (161), and its end can selectively abut against the inner sleeve (162) to fix the telescopic position.

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