An angle measuring device and method

Abstract

The present application relates to the field of variable blade angle measurement of an aero-engine, and particularly relates to an angle measurement device and method, comprising a measurement base, a measurement panel and a pointer; the measurement base is provided with a reference plane and a radial limiting plane perpendicular to the reference plane, and the end of the radial limiting plane is provided with a radial positioning structure of a machine case. During measurement, the reference plane is attached to the end face of the outer machine case, and the radial positioning structure is matched to realize radial positioning of the machine case, so that the axis of the machine case is always perpendicular to the reference plane; the pointer is rotationally arranged on the measurement panel, the measurement part thereof is attached to the blade surface to be measured, and the indication part points to the angle scale. The present application establishes a unified measurement reference through a multi-point positioning and guiding structure, is convenient to operate, significantly improves the precision and efficiency of blade angle measurement, and solves the problems of poor accuracy, low efficiency and high cost in the prior art.

Description

Technical Field

[0001] This invention relates to the field of measuring the angle of adjustable blades in aero engines, specifically to an angle measuring device and method, and more particularly to an angle measuring device and method suitable for measuring the angle of adjustable blades in aero engines. Background Technology

[0002] Aero engines are hailed as the "crown jewel of industry." In modern aero engines, especially high thrust-to-weight ratio turbofan engines and advanced axial compressors, adjustable blade technology is widely used to broaden the engine's stability margin, prevent surge, and improve operating efficiency under different conditions. These adjustable blades, typically mounted on the engine casing, include adjustable stator blades and adjustable guide vanes. Their basic working principle is based on changes in engine speed, inlet air temperature, pressure, and other operating parameters. A specialized actuation mechanism drives the blades to rotate around their journals, thereby changing the angle of attack of the blades relative to the airflow. Real-time angle adjustment optimizes the angle of attack of the airflow through the blade passage, thus improving the aerodynamic performance of the compressor or fan under off-design conditions such as low speed and high load. This effectively prevents airflow separation and rotational stall, playing a crucial role in ensuring engine thrust response, fuel economy, and structural integrity. The precision of the adjustable blade angle directly affects the overall performance, safety, and lifespan of the aero engine. Any deviation in the angle of an adjustable blade can lead to aerodynamic imbalance, reduced efficiency, increased vibration, and even, in extreme cases, serious malfunctions such as surge or blade fatigue fracture. Therefore, accurate measurement of the adjustable blade angle is an essential and crucial fundamental process in engine research and development, manufacturing, periodic overhauls, and routine maintenance during service.

[0003] In current aero-engine manufacturing and maintenance practices, the most traditional and common method for measuring adjustable blade angles is to use general-purpose measuring tools, such as mechanical angle gauges or vernier protractors. Operators must hold these tools and manually align their measuring surfaces with the specific profile of the blade being measured and a pre-set reference surface on the casing before reading the scale value. This method relies heavily on the operator's experience and visual judgment; the measurement process is highly dependent on manual skill, requiring operators to possess a high level of proficiency and stable operating techniques. To ensure the reliability of the measurement results, it is usually necessary for the same operator to perform multiple measurements and take the average, or for multiple operators to perform measurements separately and cross-verify, which undoubtedly increases the time and labor costs required for a single measurement. More advanced measurement methods introduce non-contact measurement technologies, such as three-dimensional measurement systems based on optical imaging or laser scanning. These systems acquire point cloud data of the blade surface using high-resolution cameras or laser profilometers, then use complex software algorithms for data processing and model fitting to ultimately calculate the blade angle. Compared to manual measurement, optical or laser measurement methods improve measurement accuracy and repeatability to a certain extent. However, such high-precision measuring equipment is extremely expensive and has high requirements for the operating environment.

[0004] Therefore, how to create a blade angle measurement solution that can overcome the above-mentioned defects and achieve accurate, convenient, reliable and low-cost measurement is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the problems of poor accuracy, low efficiency, and high cost in the measurement of adjustable blade angles of aero-engines in existing technologies, this invention provides an angle measurement device and method.

[0006] To achieve the above objectives, the present invention employs the following technical solution: This invention provides an angle measuring device, including a measuring base, a measuring panel, and a pointer; The measuring base includes a reference plane and a radial limiting surface perpendicular to it; the end of the radial limiting surface is provided with a casing radial positioning structure; during measurement, the reference plane is in contact with the end face of the outer casing, and the casing radial positioning structure cooperates with the reference plane to perform casing radial positioning, so that the casing axis is always perpendicular to the reference plane. The measuring panel is disposed on the radial limiting surface, the center line of the measuring panel is perpendicular to the reference plane, and the measuring panel is provided with an angle scale. The pointer is mounted on the measuring panel and includes a measuring part and an indicator part connected thereto. During measurement, the measuring part is in contact with the surface of the blade to be measured, and the indicator part is an angle scale.

[0007] Optionally, the radial positioning structure of the casing is a groove provided at the end of the radial limiting surface, and the groove is fitted with the stop structure of the inner casing.

[0008] Optionally, a guide rod is also provided at the end of the radial limiting surface, and during measurement, the cylindrical surface of the guide rod is in contact with the inner wall of the inner casing.

[0009] Optionally, a first support cylinder is provided between the pointer and the measuring panel. One end of the first support cylinder is connected to the measuring panel by a first screw, and the other end is hinged to the pointer by a first nut.

[0010] Optionally, the measuring panel is also provided with a fixing strip.

[0011] Optionally, a second supporting cylinder is provided between the fixing strip and the measuring panel, and the second supporting cylinder, the fixing strip and the measuring panel are fixedly connected by a second screw.

[0012] Optionally, the measuring panel and the radial limiting surface are positioned by a locating pin with a pin hole fit.

[0013] Optionally, the measuring panel is fixedly connected to the radial limiting surface by a third screw.

[0014] Optionally, the angle scale ranges from -10° to 50°, with the vertical scale line at 20° and the angle decreasing clockwise by 1° per division.

[0015] The present invention also provides an angle measurement method using the above-described angle measuring device, comprising: Make the reference plane fit with the end face of the outer casing, make the radial positioning structure of the casing radially position the inner casing, and make the casing axis always perpendicular to the reference plane. Move the angle measuring device along the circumference of the casing to the position of the blade to be measured, rotate the pointer measuring part to fit the surface of the blade to be measured, and record the angle scale reading indicated by the indicator on the measuring panel to complete the angle measurement.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention provides an angle measuring device. Through structural design of the measuring base, a reference plane is designed to force the base plane of the entire device to be perpendicular to the rotation axis of the casing, establishing an absolute horizontal reference. A radially limiting surface perpendicular to the reference plane and a radial positioning structure of the casing ensure precise radial positioning of the casing, guaranteeing that the device center coincides with the casing axis and preventing radial movement. By the contact between the measuring base reference surface and the casing end face, and the radial positioning surface and casing radial positioning structure working in tandem with the casing radial positioning, a measuring coordinate system strictly perpendicular to the casing axis and radially fixed is established. Based on this, a rotatable pointer whose measuring profile precisely matches the theoretical profile of the blade is used to force the pointer into contact with the blade profile. Any change in the blade angle forces the pointer to rotate around its axis by the same amount of angle, which is directly read from the position of the pointer tip on a pre-calibrated angle scale. Thus, the complex spatial blade angle measurement is transformed into a high-precision, reproducible planar angle measurement, achieving efficient, accurate, and reliable measurement. Compared to existing angle measuring devices, this application utilizes a reference plane and radial positioning structure to fix the device's spatial orientation, eliminating the need for operators to maintain balance. Measurements are completed simply by moving the device and rotating the pointer, significantly reducing the skill requirements and complexity of operation, and improving measurement accuracy and efficiency. Furthermore, when measuring all blades, the device's position relative to the casing axis remains constant, ensuring that all blades are measured on the same radial and axial cross-sections, resulting in highly repeatable and comparable measurement results. Compared to non-contact measurement technologies, this device is simpler in structure, lower in cost, and its accuracy is unaffected by the environment, making it more versatile.

[0017] The radial positioning structure of the casing is a groove at the end of the radial limiting surface, which engages with the stop structure of the inner casing. This engagement of the groove and stop is a simple, reliable, and easy-to-manufacture radial positioning method. Compared to existing technologies that lack radial limiting or employ complex clamping mechanisms, this structure can prevent radial movement in real time during measurement and device movement, avoiding device drop and damage to the blades and inner casing wall. Simultaneously, it ensures that the device's rotation center coincides with the casing axis, further improving measurement accuracy and operational safety.

[0018] The introduction of the guide rod allows the cylindrical surface of the guide rod to slide tightly against the inner wall of the inner casing when the device moves circumferentially. The movement trajectory of the forced device is a precise circular path around the axis of the casing, thus ensuring that all blades under test are measured on the same measurement section perpendicular to the blade axis. At the same time, the contact between the guide rod and the inner wall of the inner casing further assists in radial positioning, complementing the groove and ensuring that the device maintains a stable radial position during circumferential motion.

[0019] An axial clearance is provided by a first supporting cylinder, and a hinge structure is formed by screws and nuts, allowing the pointer to rotate smoothly and freely around a fixed axis without obstruction. This structure is simple and reliable, avoiding direct friction or jamming between the pointer and the panel, ensuring that the pointer deflects accurately under slight external force, thus truly reflecting the blade angle and improving the sensitivity and repeatability of the measurement.

[0020] The measuring panel is also equipped with a fixing strip, which is located on the movement path of the pointer. This effectively prevents the pointer from swinging excessively and avoids deformation or damage to the pointer due to excessive movement.

[0021] The measuring panel and the radial limiting surface are positioned by a positioning pin with a pin hole fit. The pin positioning can ensure that there is a unique and precise installation position between the measuring panel and the measuring base, avoiding the offset of the scale reference caused by repeated disassembly or processing errors, and ensuring that the scale value calibrated by the factory is always accurate and effective in actual use.

[0022] This invention also provides an angle measurement method using the aforementioned angle measuring device. This method aligns the reference plane with the outer casing end face and positions the casing radially with the inner casing radially, ensuring the casing axis remains perpendicular to the reference plane. A single placement operation establishes a globally unified reference, and subsequent measurements of all blades require only three simple actions: moving, rotating the pointer, and taking the reading. This significantly simplifies the process and reduces measurement time, meeting the urgent efficiency demands of production lines and maintenance sites. Furthermore, during movement, the circumferential motion trajectory of the device is strictly limited to an arc around the casing axis. Therefore, for all blades, the radial and axial positions (distance from the inner casing wall) of the pointer measuring part are identical, achieving true measurement of the same cross-section. This ensures strict physical comparability of measurement data, further improving measurement accuracy. Attached Figure Description

[0023] Figure 1 This is an axonometric view of an angle measuring device of the present invention placed in reverse.

[0024] Figure 2 This is a front view of an angle measuring device according to the present invention.

[0025] Figure 3 This is a left view of an angle measuring device according to the present invention.

[0026] Figure 4 This is a top view of an angle measuring device according to the present invention.

[0027] Figure 5 This is a structural diagram of the measuring base of an angle measuring device according to the present invention, wherein a is a left view, b is a top view, c is a front view, and d is an axonometric view.

[0028] Figure 6 This is a structural diagram of the measuring panel of an angle measuring device according to the present invention, wherein a is a left view, b is a top view, and c is an axonometric view.

[0029] Figure 7 This is a pointer structure diagram of an angle measuring device according to the present invention, wherein a is a left view, b is a top view, and c is an axonometric view.

[0030] Figure 8 This is a structural diagram of the guide rod of an angle measuring device according to the present invention, wherein a is the left view and b is the front view.

[0031] Figure 9 This is a structural diagram showing the installation position of an angle measuring device according to the present invention.

[0032] Among them, 1-third screw, 2-locating pin, 3-pointer, 31-measuring part, 32-indicating part, 4-measuring base, 41-reference plane, 42-radial limiting surface, 421-groove, 5-measuring panel, 6-first nut, 7-first support cylinder, 8-first screw, 9-guide rod, 10-second support cylinder, 11-fixing strip, 12-second screw, 13-outer casing, 14-inner casing. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0036] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0037] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0039] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0040] See Figures 1 to 4 This invention discloses an angle measuring device, including a measuring base 4, a measuring panel 5, a pointer 3, and a guide rod 9; See Figure 5 The measuring base 4 includes a reference plane 41 and a radial limiting surface 42 perpendicular to it. A casing radial positioning structure is provided at the end of the radial limiting surface 42. During measurement, the reference plane 41 is in contact with the end face of the outer casing 13, and the casing radial positioning structure cooperates with the reference plane 41 to perform casing radial positioning, ensuring that the casing axis is always perpendicular to the reference plane 41. Preferably, the casing radial positioning structure is a groove 421 provided at the end of the radial limiting surface 42, and the groove 421 is fitted with the stop structure of the inner casing 14. Preferably, the measuring base 4 is provided with positioning holes.

[0041] See Figure 6The measuring panel 5 is disposed on the radial limiting surface 42. Preferably, the measuring panel 5 is fixedly connected to the radial limiting surface 42 by a third screw 1. The centerline of the measuring panel 5 is perpendicular to the reference plane 41. The measuring panel 5 is provided with an angle scale. Preferably, the angle scale ranges from -10° to 50°, with the vertical scale line being 20°, and the angle decreasing clockwise by 1° per division. The measuring panel 5 is provided with positioning holes corresponding to the positioning holes on the measuring base 4. The two positioning holes are fitted and positioned by positioning pins 2. The measuring panel 5 is also provided with a fixing strip 11. A second supporting cylinder 10 is provided between the fixing strip 11 and the measuring panel 5. The second supporting cylinder 10, the fixing strip 11, and the measuring panel 5 are fixedly connected by a second screw 12.

[0042] See Figure 7 The pointer 3 is rotatably mounted on the measuring panel 5 and includes a measuring part 31 and an indicating part 32 connected thereto. During measurement, the measuring part 31 is in contact with the surface of the blade to be measured, and the indicating part 32 is an angle scale. Preferably, a first supporting cylinder 7 is provided between the pointer 3 and the measuring panel 5. One end of the first supporting cylinder 7 is connected to the measuring panel 5 by a first screw 8, and the other end is hinged to the pointer 3 by a first nut 6.

[0043] See Figure 8 The guide rod 9 is located at the end of the radial limiting surface 42. During measurement, the cylindrical surface of the guide rod 9 is in contact with the inner wall of the inner casing 14.

[0044] See Figure 9 In use, place the angle measuring device on the inner and outer casings; adjust the position of the angle measuring device so that the reference plane 41 of the measuring base 4 is in contact with the mounting edge of the outer casing 13, the groove 421 on the radial limiting surface 42 of the measuring base 4 is in contact with the stop of the inner casing 14, and the cylindrical surface of the guide rod 9 is in contact with the inner surface of the inner casing 14; move the angle measuring device left and right so that the lower inclined surface of the pointer 3, i.e., the measuring part 31, is completely in contact with the surface of the measuring blade. At this time, read the value on the measuring panel as the actual angle of the blade; when the blade angle changes, repeat the above measurement steps.

[0045] The present invention also provides an angle measurement method using the above-described angle measuring device, comprising: S1: Make the reference plane 41 fit with the end face of the outer casing 13, make the radial positioning structure of the casing radially positioned with the inner casing 14, and make the casing axis always perpendicular to the reference plane 41. S2: Move the angle measuring device along the circumference of the casing to the position of the blade to be measured, rotate the pointer 3 to make the measuring part 31 fit with the surface of the blade to be measured, and record the angle scale reading on the measuring panel 5 indicated by the recording indicator 32 to complete the angle measurement.

[0046] This method aligns the reference plane with the end face of the outer casing and positions the radial positioning structure of the casing radially with the inner casing, ensuring that the casing axis remains perpendicular to the reference plane. A single placement operation establishes a globally unified reference, and subsequent measurements of all blades require only three simple actions: moving, rotating the pointer, and taking the reading. This significantly simplifies the process and reduces the time required for a single measurement, meeting the urgent need for high efficiency in production lines or maintenance sites.

[0047] In summary, this invention provides an angle measuring device and method. During angle measurement, the measuring base 4 is in contact with the end faces of the inner and outer casings, ensuring that the axis of the casing is perpendicular to the reference plane 41. This eliminates the need for manual horizontal maintenance, improving measurement accuracy and reducing errors. The groove 421 on the measuring base 4 is in contact with the stop of the inner casing 14, preventing radial movement when the angle measuring device is moved and preventing it from falling and damaging the blades and casing. When measuring the blade angle, the guide rod 9 is in contact with the inner wall of the inner casing 14, ensuring a constant distance between the blade measurement section and the inner wall of the casing, guaranteeing that all blades are measured on the same section for accurate measurement. When moving the angle measuring device, the guide rod 9 is in contact with the inner wall of the inner casing, ensuring that the circumferential movement of the angle measuring device is a rotation around the casing axis, guaranteeing that all blade measurement sections are perpendicular to the blade axis, ensuring measurement consistency, significantly reducing the time and labor costs of manual verification, and improving testing efficiency and accuracy.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the technical solution of the present invention in any way. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can be modified and replaced in several simple ways, and these modifications and replacements are all within the scope of protection covered by the claims.

Claims

1. An angle measuring device, characterized in that, Includes a measuring base (4), a measuring panel (5), and a pointer (3); The measuring base (4) includes a reference plane (41) and a radial limiting surface (42) perpendicular to it; the end of the radial limiting surface (42) is provided with a casing radial positioning structure; during measurement, the reference plane (41) is in contact with the end face of the outer casing (13), and the casing radial positioning structure cooperates with the reference plane (41) to perform casing radial positioning, so that the casing axis is always perpendicular to the reference plane (41). The measuring panel (5) is set on the radial limiting surface (42), the center line of the measuring panel (5) is perpendicular to the reference plane (41), and the measuring panel (5) is provided with an angle scale; The pointer (3) is rotated and set on the measuring panel (5), including a measuring part (31) and an indicator part (32) connected thereto; during measurement, the measuring part (31) is in contact with the blade profile to be measured, and the indicator part (32) is the angle scale.

2. The angle measuring device according to claim 1, characterized in that, The radial positioning structure of the casing is a groove (421) provided at the end of the radial limiting surface (42), and the groove (421) is fitted with the stop structure of the inner casing (14).

3. The angle measuring device according to claim 1, characterized in that, The end of the radial limiting surface (42) is also provided with a guide rod (9). During measurement, the cylindrical surface of the guide rod (9) is in contact with the inner wall of the inner casing (14).

4. The angle measuring device according to claim 1, characterized in that, A first support cylinder (7) is provided between the pointer (3) and the measuring panel (5). One end of the first support cylinder (7) is connected to the measuring panel (5) by a first screw (8), and the other end is hinged to the pointer (3) by a first nut (6).

5. The angle measuring device according to claim 1, characterized in that, The measuring panel (5) is also provided with a fixing strip (11).

6. The angle measuring device according to claim 5, characterized in that, A second support cylinder (10) is provided between the fixing strip (11) and the measuring panel (5), and the second support cylinder (10), the fixing strip (11) and the measuring panel (5) are fixedly connected by a second screw (12).

7. The angle measuring device according to claim 1, characterized in that, The measuring panel (5) and the radial limiting surface (42) are positioned by a pin hole engagement via a positioning pin (2).

8. The angle measuring device according to claim 1, characterized in that, The measuring panel (5) is fixedly connected to the radial limiting surface (42) by the third screw (1).

9. The angle measuring device according to claim 1, characterized in that, The angle scale ranges from -10° to 50°, with the vertical scale line at 20°, decreasing clockwise by 1° per division.

10. An angle measurement method using the angle measuring device according to any one of claims 1-9, characterized in that, include: Make the reference plane (41) fit with the end face of the outer casing (13), make the radial positioning structure of the casing radially positioned with the inner casing (14), and make the casing axis always perpendicular to the reference plane (41). Move the angle measuring device along the circumference of the casing to the position of the blade to be measured, rotate the pointer (3) to make the measuring part (31) fit with the surface of the blade to be measured, and record the angle scale reading on the measuring panel (5) indicated by the recording indicator (32) to complete the angle measurement.

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