A lead device for measuring dynamic stress of compressor blades

Abstract

The present invention relates to a lead device for measuring dynamic stress of compressor blades, comprising a lead assembly for transmitting stress signals, a strain gauge for measuring stress, and a measuring lead connecting the strain gauge and the lead assembly, as well as a hollow front lead tube and a hollow rear lead tube; the front lead tube is used to be installed in the rear journal of the compressor and is coaxially arranged with the rear journal; the rear lead tube is used to be installed in the turbine shaft and is coaxially arranged with the turbine shaft; the measuring lead passes through the front lead tube and the rear lead tube and is connected to the lead assembly. When measuring the dynamic stress of compressor blades, the device is installed in the compressor, the entire device is coaxially arranged with the rotating shaft of the compressor, rotates with the compressor and remains colinear with the rotating shaft of the compressor during rotation, so that the entire device will not be offset and will not affect the dynamic characteristics of the compressor, thereby achieving accurate measurement of the dynamic stress of the blades.

Description

Technical Field

[0001] The present invention relates to the technical field of engine structure detection, and more specifically, to a lead device for measuring dynamic stress of compressor blades. Background Art

[0002] Compressor blades are important parts of aircraft engines, but they are also parts that are prone to failure. In order to ensure the safety of engine operation, dynamic stress measurement and analysis tests are usually carried out on the blades during the engine design phase to evaluate and determine the allowable stress level and durability of the blades under all operating conditions.

[0003] At present, most compressor blades use the front lead method when conducting dynamic stress measurement and analysis tests, such as the dynamic stress measurement installation device for compressor blades of aircraft engines with a publication number of "CN205015110U" and a publication date of February 3, 2016. The advantage of this method is that the signal transmission distance is short, but it also faces the problem of limited space and too many test channels. There are high-risk factors such as the risk of test failure caused by the lack of synchronous test signals and endangering engine safety. The rear lead method has a strong ability to synchronize test signals and poses no threat to the engine. In order to ensure engine safety and test success, the rear lead method is originally a better choice. However, since the rear lead method increases the transmission distance, the test lead system structure is complex, and the leads or other components are easily offset during the rotation of the compressor, which has a significant impact on the overall dynamic characteristics of the compressor, resulting in a decrease in the accuracy of the test results, and the rear lead method cannot be used. Summary of the invention

[0004] In order to overcome the problem of low accuracy of dynamic stress measurement by rear lead-in method in the prior art, the present invention provides a lead-in device for dynamic stress measurement of compressor blades, which can lead out the lead-in from the rear end of the compressor blade without affecting the dynamic characteristics of the compressor blade itself.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: a lead device for measuring the dynamic stress of compressor blades, including a lead assembly for stress signal transmission, a strain gauge for measuring stress and a measuring lead connecting the strain gauge and the lead assembly, as well as a hollow front lead tube and a hollow rear lead tube; the front lead tube is used to be installed in the rear shaft neck of the compressor and is arranged coaxially with the rear shaft neck; the rear lead tube is used to be installed in the turbine shaft and is arranged coaxially with the turbine shaft; the measuring lead is connected to the lead assembly after passing through the front lead tube and the rear lead tube.

[0006] In the above technical scheme, the inner cavities of the hollow front lead tube and the hollow rear lead tube are located on the axis, the strain gauge is fixedly attached to the rotating blade of the compressor, and the measuring lead connected to the strain gauge extends along the inner wall of the drum of the blade to the rear shaft neck of the compressor, and then enters into the hollow front lead tube, and then passes through the other end of the front lead tube and enters into the inner cavity of the rear lead tube, and finally passes through the rear lead tube to connect with the feed assembly, so that the signal of the strain gauge is transmitted to the feed assembly, and then transmitted through the feed assembly. Since the front lead tube and the rear lead tube are respectively arranged coaxially with the rear journal and the turbine shaft, that is, coaxially with the rotating shaft of the compressor, and the measuring leads passing through the front lead tube and the rear lead tube are all located at the axis of the two, that is, coaxially with the rotating shaft of the compressor, when the front lead tube, the rear lead tube and the measuring lead follow the rotation of the compressor, the rotation axis of the three is colinear with the rotating shaft of the compressor, avoiding the three from being offset in any direction, thereby ensuring that the dynamic characteristics of the compressor blade itself will not be affected. At the same time, the front lead tube and the rear lead tube are fixed in sections in the compressor to facilitate the installation of the device.

[0007] Preferably, it also includes a positioning sleeve sleeved on the outer surface of the front lead tube and a support ring arranged on the outer surface of the front lead tube, the outer wall of the positioning sleeve is used for interference fit with the inner wall of the rear journal; the positioning sleeve is provided with a receiving cavity and an elastic member arranged in the receiving cavity; the surface of the front lead tube is provided with a protrusion, one end of the elastic member abuts against the bottom of the receiving cavity, and the other end abuts against the protrusion; the outer surface of the support ring is provided with an elastic sealing ring for abutting against the inner wall of the rear journal. The positioning sleeve is fixed in the rear journal, and the front lead tube is pushed in the direction of the blade by the elastic force of the elastic member, so that one end of the front lead tube can maintain abutment with the end of the rear journal, making the front lead tube more stable in the rear journal. The support ring is in contact with the inner wall of the rear journal through an elastic sealing ring, and the front lead tube is fixed on the axis of the rear journal during installation. Multiple support rings can be provided and arranged at intervals, so as to fix the front lead tube and reduce the weight of the entire device, thereby reducing the impact of the front lead tube on the rotation of the rear journal. The front lead tube is fixed by the support ring, providing support force for the front lead tube and increasing the rigidity of the front lead tube. The elastic sealing ring realizes the flexible connection between the front lead tube and the rear journal, so that the overall structure and dynamic characteristics of the compressor do not change significantly, and the installation is also more convenient.

[0008] Preferably, the outer surface of the front lead tube is provided with a clamping block, and the positioning sleeve is provided with a clamping groove clamped with the clamping block. After the front lead tube is pushed by the elastic member, the front lead tube is also clamped with the clamping groove of the positioning sleeve through the clamping block, so that the front lead tube and the positioning sleeve are completely fixedly connected, and the positioning sleeve and the rear shaft neck are interference fit, which is equivalent to the positioning sleeve and the rear shaft neck being fixedly connected, thereby making the front lead tube and the rear shaft neck fixedly connected in disguise, making the front lead tube and the rear shaft neck seem to be one body, and further reducing the influence of the front lead tube on the rotation of the compressor.

[0009] Preferably, the outer surface of the rear lead tube is sleeved with a tube sleeve, and the outer surface of the tube sleeve is provided with a support portion, and the support portion is used to abut against the inner wall of the turbine shaft. The rear lead tube is fixed on the axis of the turbine shaft by the limiting effect of the support portion, and the support portion can be provided in multiple and spaced apart, so as to achieve the goal of fixing the rear lead tube and reducing the weight of the entire device, thereby reducing the influence of the rear lead tube on the rotation of the turbine shaft. At the same time, the rear lead tube is fixed by the support portion, providing support force for the rear lead tube, and the rigidity of the rear lead tube can also be increased.

[0010] Preferably, an elastic rubber ring is provided on the outer surface of the support portion, and the support portion abuts against the inner wall of the turbine shaft through the elastic rubber ring. The elastic rubber ring is used to achieve a flexible connection between the rear lead tube and the turbine shaft, so that the overall structure and dynamic characteristics of the compressor do not change significantly, and the installation is also more convenient.

[0011] Preferably, one end of the rear lead tube is provided with a snap-in cavity, and the end of the front lead tube is installed in the snap-in cavity. The front lead tube and the rear lead tube are spliced, and the measuring lead is not exposed outside the two, ensuring that the measuring lead is always on the axis of the compressor shaft. The front lead tube and the rear lead tube are connected through the snap-in cavity, avoiding the addition of connectors that may cause changes in the dynamic characteristics of the compressor and turbine shaft.

[0012] Preferably, a shoulder is provided at one end of the rear lead tube close to the front lead tube, and the sleeve abuts against the shoulder. The sleeve is restricted by the shoulder during installation, so that the sleeve can be installed in place more quickly.

[0013] Preferably, it also includes a support seat and a hollow positioning shaft rotatably connected to the support seat, the positioning shaft is connected to the end of the rear lead tube away from the front lead tube; the measuring lead passes through the positioning shaft and is connected to the lead assembly. The hollow positioning shaft is coaxially arranged with the rear lead tube, and the measuring lead passes through the positioning shaft and is connected to the lead assembly. The positioning shaft can keep the measuring lead connected to the lead assembly in a state of being colinear with the compressor rotation axis, further reducing the influence of the measuring lead on the compressor rotation, so that the dynamic characteristics of the compressor are not affected.

[0014] Preferably, the induction assembly includes an induction and a slip ring bracket for supporting the induction; the induction includes a slip ring lead and a slip ring, and the measuring lead is connected to the slip ring lead; the slip ring bracket is fixedly connected to the support seat.

[0015] Preferably, the positioning shaft is provided with a polygonal hole, and the end of the rear lead tube is provided with a connection portion that matches the polygonal hole. The positioning shaft can rotate with the rear lead tube, reducing the movement obstruction caused by the relative movement of the positioning shaft and the measuring lead, thereby making the rotation of the measuring lead smoother. The positioning shaft and the rear lead tube do not need to be connected by a connector, reducing the influence of the connector on the rotation of the compressor.

[0016] Compared with the prior art, the beneficial effect is: when measuring the dynamic stress of the compressor blades, the device is installed in the compressor, the entire device is arranged coaxially with the compressor shaft, rotates with the compressor and remains colinear with the compressor shaft during rotation, so that the entire device will not be offset and will not affect the dynamic characteristics of the compressor, thereby achieving accurate measurement of the dynamic stress of the blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a lead device for measuring dynamic stress of compressor blades according to the present invention;

[0018] Figure 2 yes Figure 1 A partial enlarged view of position A;

[0019] Figure 3 yes Figure 1 A local enlarged view of position B;

[0020] Figure 4 yes Figure 1 A local enlarged view of the C position;

[0021] Figure 5 It is a schematic diagram of the working state of the present invention. DETAILED DESCRIPTION

[0022] The drawings are only for illustrative purposes and cannot be construed as limiting the present invention. To better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged, or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are only for illustrative purposes and cannot be construed as limiting the present invention.

[0023] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "long", "short" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0024] The technical solution of the present invention is further described in detail below through specific embodiments and in conjunction with the accompanying drawings:

[0025] Example

[0026] like Figure 1-4 The figure shows a lead device for measuring dynamic stress of compressor blades, including a lead assembly 1 for transmitting stress signals, a strain gauge 2 for measuring stress, a measuring lead 3 connecting the strain gauge 2 and the lead assembly 1, and a hollow front lead tube 4 and a hollow rear lead tube 5; the front lead tube 4 is used to be installed in the rear journal 11 of the compressor and is arranged coaxially with the rear journal 11; the rear lead tube 5 is used to be installed in the turbine shaft 12 and is arranged coaxially with the turbine shaft 12; the measuring lead 3 passes through the front lead tube 4 and the rear lead tube 5 and is connected to the lead assembly 1.

[0027] The invention also includes a positioning sleeve 6 sleeved on the outer surface of the front lead tube 4 and a support ring 403 arranged on the outer surface of the front lead tube 4. The outer wall of the positioning sleeve 6 is used for interference fit with the inner wall of the rear journal 11. The positioning sleeve 6 is provided with a receiving cavity 601 and an elastic member 602 arranged in the receiving cavity 601. The surface of the front lead tube 4 is provided with a protrusion 401. One end of the elastic member 602 abuts against the bottom of the receiving cavity 601, and the other end abuts against the protrusion 401. The outer surface of the support ring 403 is provided with an elastic sealing ring 4031 for abutting against the inner wall of the rear journal. The positioning sleeve 6 is fixed in the rear journal 11. Through the elastic force of the elastic member 602, the front lead tube 4 is pushed toward the direction of the blade, so that one end of the front lead tube 4 can keep abutting against the end of the rear journal 11, making the front lead tube 4 more stable in the rear journal 11. The support ring 403 is in contact with the inner wall of the rear journal through the elastic sealing ring 4031, and the front lead tube 4 is fixed on the axis of the rear journal during installation. A plurality of support rings 403 can be provided and arranged at intervals, so as to fix the front lead tube 4 and reduce the weight of the entire device, thereby reducing the influence of the front lead tube 4 on the rotation of the rear journal. The front lead tube 4 is fixed by the support ring 403, providing support force for the front lead tube 4, and increasing the rigidity of the front lead tube 4. The elastic sealing ring 4031 realizes the flexible connection between the front lead tube 4 and the rear journal, so that the overall structure and dynamic characteristics of the compressor do not change significantly, and the installation is also more convenient.

[0028] Specifically, the outer surface of the front lead tube 4 is provided with a clamping block 402, and the positioning sleeve 6 is provided with a clamping groove 603 clamped with the clamping block 402. After the front lead tube 4 is pushed by the elastic member 602, the front lead tube 4 is also clamped with the clamping groove 603 of the positioning sleeve 6 through the clamping block 402, so that the front lead tube 4 and the positioning sleeve 6 are completely fixedly connected, and the positioning sleeve 6 and the rear journal 11 are interference fit, which is equivalent to the positioning sleeve 6 and the rear journal 11 being fixedly connected, thereby making the front lead tube 4 and the rear journal 11 fixedly connected in disguise, making the front lead tube 4 and the rear journal 11 as one body, further reducing the influence of the front lead tube 4 on the rotation of the compressor.

[0029] The outer surface of the rear lead tube 5 is covered with a sleeve 7, and the outer surface of the sleeve 7 is provided with a support portion 701, and the support portion 701 is used to abut against the inner wall of the turbine shaft 12. The rear lead tube 5 is fixed on the axis of the turbine shaft 12 by the limiting effect of the support portion 701. The support portion 701 can be provided in multiple numbers and arranged at intervals, so as to fix the rear lead tube 5 and reduce the weight of the entire device, thereby reducing the influence of the rear lead tube 5 on the rotation of the turbine shaft 12. At the same time, the rear lead tube 5 is fixed by the support portion 701, providing support force for the rear lead tube 5, and the rigidity of the rear lead tube 5 can also be increased.

[0030] Specifically, an elastic rubber ring 702 is provided on the outer surface of the support portion 701, and the support portion 701 abuts against the inner wall of the turbine shaft 12 through the elastic rubber ring 702. The elastic rubber ring is used to achieve a flexible connection between the rear lead tube 5 and the turbine shaft 12, so that the overall structure and dynamic characteristics of the compressor and the turbine shaft do not change significantly, and the installation is also more convenient. The elastic rubber ring 702 and the elastic sealing ring 4031 can both be O-rings.

[0031] Furthermore, a snap-fit ​​cavity is provided at one end of the rear lead tube 5, and the end of the front lead tube 4 is installed in the snap-fit ​​cavity. The front lead tube 4 and the rear lead tube 5 are spliced, and the measuring lead 3 will not be exposed outside the two, ensuring that the measuring lead 3 is always on the axis of the compressor shaft. The front lead tube 4 and the rear lead tube 5 are connected through the snap-fit ​​cavity to avoid adding connectors and causing changes in the dynamic characteristics of the compressor and turbine shaft. A shoulder is provided at one end of the rear lead tube 5 close to the front lead tube, and the sleeve 7 abuts against the shoulder. The sleeve 7 is restricted by the shoulder and can be quickly installed in place during installation.

[0032] In addition, it also includes a support seat 8 and a hollow positioning shaft 9 rotatably connected to the support seat 8, the positioning shaft 9 is connected to one end of the rear lead tube 5 away from the front lead tube 4; the measuring lead 3 passes through the positioning shaft 9 and is connected to the lead assembly 1. The hollow positioning shaft 9 is coaxially arranged with the rear lead tube 5, and the measuring lead 3 passes through the positioning shaft 9 and is connected to the lead assembly 1. The positioning shaft 9 can keep the measuring lead 3 connected to the lead assembly 1 in a state colinear with the compressor rotation axis, further reducing the influence of the measuring lead 3 on the compressor rotation, so that the dynamic characteristics of the compressor are not affected. The positioning shaft 9 is provided with a polygonal hole, and the end of the rear lead tube 5 is provided with a connecting portion that cooperates with the polygonal hole. The positioning shaft 9 can rotate with the rear lead tube 5, reducing the movement obstruction caused by the relative movement of the positioning shaft 9 and the measuring lead 3, so that the rotation of the measuring lead 3 is smoother. The positioning shaft 9 and the rear lead tube 5 do not need to be connected with a connector, reducing the influence of the connector on the compressor rotation.

[0033] In this embodiment, the induction assembly 1 includes an induction and a slip ring bracket 101 for supporting the induction; the induction includes a slip ring lead 102 and a slip ring 103, and the measuring lead 3 is connected to the slip ring lead 102; the slip ring bracket 101 is fixedly connected to the support seat 8.

[0034] The working principle or workflow of this embodiment is as follows: Figure 5As shown, the inner cavities of the hollow front lead tube 4 and the hollow rear lead tube 5 are located on the axis, the strain gauge is fixedly attached to the rotating blade 10 of the compressor, the measuring lead 3 connected to the strain gauge extends along the inner wall of the drum of the blade to the rear shaft neck 11 of the compressor, and then enters into the hollow front lead tube 4, and then passes through the other end of the front lead tube 4 and enters into the inner cavity of the rear lead tube 5, and finally passes through the rear lead tube 5 to be connected to the induction assembly 1, so that the signal of the strain gauge is transmitted to the induction assembly 1, and then transmitted through the induction assembly 1. Since the front lead tube 4 and the rear lead tube 5 are respectively coaxially arranged with the rear journal 11 and the turbine shaft 12, that is, coaxially arranged with the rotating shaft of the compressor, and the measuring lead 3 passing through the front lead tube 4 and the rear lead tube 5 are all located at the axis of the two, that is, coaxially arranged with the rotating shaft of the compressor, when the front lead tube 4, the rear lead tube 5 and the measuring lead 3 rotate with the compressor, the rotation axis of the three is colinear with the rotating shaft of the compressor, avoiding the three from being offset in any direction, thereby ensuring that the dynamic characteristics of the compressor blade itself will not be affected. Through the action of the positioning sleeve 6 and the support part 701, the whole device is firmly connected with the compressor, and the whole lead device is integrated with the compressor, so that when the compressor rotates, it is not affected by the lead device. At the same time, the front lead tube 4 and the rear lead tube 5 are fixed in the compressor in sections, which is convenient for the installation of the device.

[0035] The beneficial effects of this embodiment are as follows: when measuring the dynamic stress of compressor blades, the device is installed in the compressor, and the entire device is arranged coaxially with the compressor shaft. It rotates with the compressor and remains colinear with the compressor shaft during rotation, so that the entire device will not be offset and will not affect the dynamic characteristics of the compressor, thereby achieving accurate measurement of the dynamic stress of the blades.

[0036] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A lead device for measuring dynamic stress of a compressor blade, comprising a lead assembly (1) for transmitting a stress signal, a strain gauge (2) for measuring stress, and a measuring lead (3) connecting the strain gauge (2) and the lead assembly (1), characterized in that: It also comprises a hollow front lead tube (4) and a rear lead tube (5); the front lead tube (4) is used to be installed in the rear journal of the compressor and is arranged coaxially with the rear journal; the rear lead tube (5) is used to be installed in the turbine shaft and is arranged coaxially with the turbine shaft; the measuring lead (3) passes through the front lead tube (4) and the rear lead tube (5) and is connected to the lead assembly (1); The invention also comprises a positioning sleeve (6) sleeved on the outer surface of the front lead tube (4) and a support ring (403) arranged on the outer surface of the front lead tube (4); the outer wall of the positioning sleeve (6) is used for interference fit with the inner wall of the rear journal; the positioning sleeve (6) is provided with a receiving cavity (601) and an elastic member (602) arranged in the receiving cavity (601); the surface of the front lead tube (4) is provided with a protrusion (401), one end of the elastic member (602) abuts against the bottom of the receiving cavity (601), and the other end abuts against the protrusion (401); the outer surface of the support ring (403) is provided with an elastic sealing ring (4031) for abutting against the inner wall of the rear journal; the outer surface of the front lead tube (4) is provided with a clamping block (402), and the positioning sleeve (6) is provided with a clamping groove (603) clamped with the clamping block (402).

2. A lead wire device for measuring dynamic stress of compressor blades according to claim 1, characterized in that: The outer surface of the rear lead tube (5) is sleeved with a tube sleeve (7), and the surface of the tube sleeve (7) is provided with a support portion (701), and the support portion (701) is used to abut against the inner wall of the turbine shaft.

3. A lead wire device for measuring dynamic stress of compressor blades according to claim 2, characterized in that: An elastic rubber ring (702) is provided on the outer surface of the support portion (701), and the support portion (701) abuts against the inner wall of the turbine shaft via the elastic rubber ring (702).

4. A lead wire device for measuring dynamic stress of compressor blades according to claim 2, characterized in that: One end of the rear lead tube (5) is provided with a clamping cavity, and the end of the front lead tube (4) is inserted into the clamping cavity.

5. A lead wire device for measuring dynamic stress of compressor blades according to claim 2, characterized in that: The rear lead tube (5) is provided with a shoulder at one end close to the front lead tube, and one end of the tube sleeve (7) abuts against the shoulder.

6. A lead wire device for measuring dynamic stress of compressor blades according to claim 1, characterized in that: It also comprises a support seat (8) and a hollow positioning shaft (9) rotatably connected to the support seat (8); the positioning shaft (9) is connected to one end of the rear lead tube (5) away from the front lead tube (4); the measuring lead (3) passes through the positioning shaft (9) and is connected to the lead assembly (1).

7. A lead wire device for measuring dynamic stress of compressor blades according to claim 6, characterized in that: The induction device assembly (1) comprises an induction device and a slip ring bracket (101) for supporting the induction device; the induction device comprises a slip ring lead (102) and a slip ring (103), and the measuring lead (3) is connected to the slip ring lead (102); the slip ring bracket (101) is fixedly connected to the support seat (8).

8. A lead wire device for measuring dynamic stress of compressor blades according to claim 6, characterized in that: The positioning shaft (9) is provided with a polygonal hole, and the end of the rear lead tube (5) is provided with a connecting portion that matches the polygonal hole.

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