Tool and method for measuring axial dimension of rotor and stator

Abstract

According to the rotor and stator axial dimension measuring tool, the rotor and stator axial dimension is the axial distance between the rear mounting edge of an intermediate case and a centering boss, the tool comprises an external supporting frame and a core rod, and the external supporting frame is used for abutting against the rear mounting edge of the intermediate case; the core rod extends into a shaft cavity of the rotor and stator, and the tail end of the core rod abuts against the centering boss. Wherein the core rod is movably arranged on the external support frame, and the measuring balance surface is close to the front end side. The invention further provides a rotor and stator axial dimension measuring method. According to the rotor and stator axial dimension measuring tool and method, the low-pressure rotor and stator axial dimension measuring process can be simplified.

Description

Technical Field

[0001] The present invention relates to the field of engine assembly, and in particular to the field of measurement in the assembly stage. Background Art

[0002] Aircraft engines have a complex structure and a large number of parts. The engine body can be divided into a fan case unit, a core unit and a low-pressure turbine unit according to the unit body. Among them, one or two fulcrums supporting the unit body generally have clearance, which can produce axial movement. In order to ensure that the rotor and stator blades are not scraped during the test run, an adjustment pad must be selected at the rotor to adjust the axial clearance between the front and rear of the rotor disk. The size calculation of the adjustment pad is one of the key tasks in the assembly stage of aircraft engines. An adjustment pad of appropriate thickness can ensure engine performance and safety and reliability. However, traditional measurement methods require more steps and are more complicated to operate.

[0003] Therefore, how to quickly and accurately measure and calculate the axial dimensions of the low-pressure rotor and stator is extremely important for the subsequent selection of adjustment pads and docking of large components. Summary of the invention

[0004] The purpose of the present invention is to provide a rotor-stator axial dimension measuring tool, which can simplify the axial dimension measuring process of a low-pressure rotor-stator.

[0005] In order to achieve the above-mentioned purpose, a rotor-stator axial dimension measuring tool is used to measure the axial dimension of the rotor-stator. The rotor-stator includes a rear mounting edge of an intermediate casing located at the end of an intermediate casing and a centering boss located on the shaft. The axial dimension of the rotor-stator is the axial distance from the rear mounting edge of the intermediate casing to the centering boss. The tool includes an external support frame and a core rod. The external support frame is used to abut against the rear mounting edge of the intermediate casing; the core rod extends into the axial cavity of the rotor-stator, and its tail end is used to abut against the centering boss; wherein the core rod is movably arranged on the external support frame, and also includes a measuring datum surface close to the front end side.

[0006] In one or more embodiments, the centering boss is arranged on the fan shaft, and the tail end of the core rod is also provided with a spline for cooperating with the spline on the fan shaft.

[0007] In one or more embodiments, the tool further includes a clamping bolt connected to the front end of the mandrel, and the clamping bolt is used to push the mandrel to move axially.

[0008] In one or more embodiments, the tool further comprises a force sensor disposed between the hold-down bolt and the mandrel.

[0009] In one or more embodiments, the external support frame is detachably fixed to the rear mounting edge of the intermediate casing by bolt fasteners.

[0010] Another object of the present invention is to provide a method for measuring the axial dimensions of a rotor and a stator, which is measured using the above-mentioned rotor and a stator axial dimension measuring tool, and the method includes the following steps: placing an external support frame against the rear mounting edge of an intermediate casing; extending a core rod into the axial cavity of the rotor and abutting the tail end of the core rod against the centering boss; applying an axial force to the core rod to push the fulcrum bearing to a forward thrust state; measuring the distance from the measuring datum surface of the core rod to the rear mounting edge of the intermediate casing, and obtaining the length from the measuring datum surface of the core rod to the tail end; and finding the bearing clearance of the fulcrum bearing.

[0011] The above-mentioned rotor-stator axial dimension measurement tool and method do not need to separately measure the axial dimensions of the intermediate casing and the first and second fulcrums. After using a core rod to directly push the first and second fulcrum bearings to the forward position, the low-pressure rotor-stator axial dimension measurement can be directly performed. This can simplify the measurement process and reduce the measurement difficulty, thereby improving the engine assembly efficiency and quality, and providing quick guidance for the selection of adjustment pads. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0013] Figure 1 It is a simplified diagram of the engine structure;

[0014] Figure 2 It is a schematic diagram of the measurement principle of the existing low-pressure rotor-stator;

[0015] Figure 3 It is a schematic diagram of the coordination between the rotor-stator axial dimension measuring tool and the rotor-stator;

[0016] Figure 4A-4B is a schematic diagram of the mandrel;

[0017] Figure 5A-5B is a schematic diagram of the external support frame;

[0018] Figure 6 It is a flow chart of the method for measuring the axial dimensions of the rotor and stator.

[0019] Symbols and Markings

[0020] 1 Fan Blade

[0021] 2 Fan case

[0022] 3 Intermediate Casing

[0023] 4 Core engine rotor

[0024] 5 core machine Jingzi

[0025] 6 Low vortex rotor

[0026] 7 Low-pressure turbine stator case

[0027] 8 Turbine rear casing

[0028] 9-stage inter-casing

[0029] 10 Boost Stage

[0030] 11 Intermediate casing rear mounting edge

[0031] 12 Adjustment pad

[0032] 13 Locating shoulder

[0033] 14 Centering boss

[0034] 16 Fan shaft

[0035] 31 External support frame

[0036] 32 Mandrel

[0037] 33 Bolt fasteners

[0038] 34 Tightening bolt

[0039] 35 Force Sensor

[0040] 322 Spline

[0041] 323 Measurement reference surface DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0043] It should be noted that these and other subsequent drawings are only examples and are not drawn to scale, and should not be used to limit the actual scope of protection required by the present invention.

[0044] Figure 1 The brief structure of an aircraft engine is shown, including fan blades 1, a fan casing 2, an intermediate casing 3, a core engine rotor 4, a core engine stator 5, a low-vortex rotor 6, a low-pressure turbine stator casing 7, a turbine rear casing 8, an interstage casing 9, a boost stage 10 and a fan shaft 16, and also includes five fulcrums A, B, C, D, and E. The first fulcrum A and the second fulcrum B are generally ball bearings with axial clearance, which can produce axial micro-motion.

[0045] The connection between the core engine stator 5 and the intermediate casing 3 is the intermediate casing rear mounting edge 11 , which abuts against the front stator mounting edge. The fan shaft 16 has a positioning shoulder 13 and a centering boss 14 .

[0046] Among them, adjustment pads 12 need to be arranged at the first fulcrum A and the second fulcrum B to adjust the axial clearance behind the front disc of the rotor disc. Therefore, the axial distance from the rear mounting edge 11 of the intermediate casing to the centering boss 14 needs to be measured to determine the appropriate thickness of the adjustment pads 12.

[0047] The method for measuring the axial dimensions of a traditional low-pressure rotor is as follows.

[0048] like Figure 2 As shown, first measure the axial dimension L2 of the intermediate casing unit body, which is the distance from the intermediate casing rear mounting edge 11 to the intermediate casing front mounting edge, and the intermediate casing rear mounting edge abuts against the first and second fulcrum rear mounting edges N. Since the unit body size of the intermediate casing 3 is relatively large, higher requirements are placed on the specifications of the three-coordinate measuring equipment, and higher requirements are placed on flipping, hoisting, and measurement.

[0049] Then measure the axial distance VM from the one-two-pivot rear mounting edge N to the positioning shoulder 13 of the one-two-pivot unit body when the bearings of the first pivot A and the second pivot B are in the forward-pushed state.

[0050] Then, the axial dimension Lc from the centering boss 14 on the fan shaft 16 of the first and second pivots to the positioning shoulder 13 is obtained. Since the fan shaft centering boss 14 is far from the mounting edge N after the first and second pivots, and the fan shaft diameter is small, it is not conducive to direct measurement by a general measuring tool.

[0051] Subsequently, the bearing clearance ZY2 of the ball bearing at the second fulcrum B is found.

[0052] The axial dimension of the low-pressure rotor stator is calculated according to the formula, that is, the axial distance L1=L2+VM-Lc-(ZY2 / 2) from the rear mounting edge of the intermediate casing, that is, the front stator mounting edge to the centering boss 14 at the theoretical center position of the two-point bearing.

[0053] It can be seen that the above method has many dimension chains and the measurement is cumbersome. Often a data error will affect the entire calculation result.

[0054] The rotor-stator axial dimension measurement method and tooling disclosed in the present invention can effectively reduce the intermediate processes, simplify the current complex measurement and calculation processes, greatly reduce the quality risk links, and avoid inaccurate calculation results caused by tolerance accumulation.

[0055] Reference Figure 3As shown, the tooling includes an external support frame 31 and a core rod 32. The external support frame 31 abuts against the rear mounting edge 11 of the intermediate casing. For example, the external support frame 31 is fixed to the rear mounting edge 11 of the intermediate casing 3 by bolt fasteners 33. The core rod 32 extends into the rotor-stator shaft cavity to achieve axial positioning and cylindrical centering. The core rod 32 is used to push the bearings of the first and second fulcrums to produce axial movement inside, so that the bearings of the first and second fulcrums are in a forward push state for subsequent measurement.

[0056] like Figure 4A-4B As shown, the tail end 321 of the mandrel 32 abuts against the centering boss 14. Preferably, the tail end 321 of the mandrel 32 is provided with a spline 322, and the spline 322 is in contact with the spline on the bracket 16 to complete the fixation of the mandrel. The mandrel 32 is movably arranged on the external support frame 31, and also includes a measurement criterion surface 322 near the front end side.

[0057] The core rod 32 has an axial distance L core , where L core is the axial length from the reference surface 322 to the tail end 321 .

[0058] The tooling also includes a clamping bolt 34 and a force sensor 35 . The clamping bolt 34 passes through a threaded hole 318 on the external support frame 31 and is connected to the force sensor 35 . The front end of the core rod 32 is located in the positioning cavity 319 , and the force sensor 35 is located between the core rod 32 and the clamping bolt 34 .

[0059] like Figure 5A-5B As shown, the required axial force is applied to the force sensor 35 by the clamping bolt 34 to push the core rod 32 to move axially, so that the tail end 321 of the core rod 32 applies axial force to the centering boss 14, causing the ball bearings at the first and second fulcrums to move forward axially and be in a forward push state, which is the prerequisite for accurate measurement of the axial dimension L1.

[0060] Generally speaking, when the axial force is small, it is considered difficult to push the bearing to move, and when it is too large, it will also damage the engine parts. Therefore, when the axial force of the clamping bolt 34 displayed by the force sensor 35 is within the appropriate range, it can be considered that the ball bearing of the first and second fulcrums has axial displacement. The force range is determined according to different engine specifications. For example, in one embodiment, the axial force of the clamping bolt 34 in the range of 1000 to 1600N is regarded as an effective driving force. In this way, it is easy to achieve the forward push limit measurement position of the first and second fulcrum unit in the assembled state, so that the axial assembly size control of the intermediate casing and the first and second fulcrums is more accurate.

[0061] At this time, use a ruler, a depth gauge or other tool to measure the axial distance from the rear mounting edge 11 of the intermediate casing to the measuring reference surface 323 of the mandrel 32, which is recorded as Lmeasure. Lmeasure is located outside the engine shaft cavity, so it can be directly measured using a ruler, a depth gauge or other tool.

[0062] Therefore, the tooling directly simplifies the axial dimension calculation formula between the intermediate casing rear mounting edge 11 of the intermediate casing 3 and the centering boss 14 of the one-two-pivot low-pressure rotor stator to L1=Lmeasure+Lcore-(ZY2 / 2).

[0063] In this way, there is no need to measure the axial dimension separately before assembling the intermediate casing and the one or two fulcrums. The one or two fulcrums can be directly assembled to the intermediate casing, reducing the measurement items and calculations in the process. Instead, the axial dimension of the low-pressure rotor and stator is directly measured by measuring the axial distance L from the core rod 32 and the measuring reference surface 323 from the rear mounting edge 11 of the intermediate casing to the core rod 32, which breaks through the current complex dimension chain calculation method, reduces the measurement or transcription process of multiple dimensions, reduces risk links, and provides the possibility for quickly obtaining a suitable low-pressure adjustment pad.

[0064] In addition, the method of using the core rod 32 to push the bearing forward at one or two fulcrums internally is simpler than applying force to the outside of the unit body to make the bearing reach the forward-pushing state. It can also ensure that the bearing reaches the forward-pushing state, significantly reducing the impact of the forward-pushing state on the measurement error.

[0065] Combined with the introduction of the above-mentioned rotor-stator axial dimension measuring tool, it can be connected to a rotor-stator axial dimension measuring method, which includes the following steps: placing the external support frame against the rear mounting edge of the intermediate casing; extending the core rod into the axial cavity of the rotor-stator, and making the tail end of the core rod against the centering boss; applying axial force to the core rod to push the bearings of one or two fulcrums into a forward state; measuring the distance from the measuring aligning surface of the core rod to the rear mounting edge of the intermediate casing, and obtaining the length from the measuring aligning surface of the core rod to the tail end; finding the bearing clearance of the fulcrum bearing.

[0066] Finally, the axial spacing L1 from the rear mounting edge of the intermediate casing to the centering boss is directly obtained through the formula L1=Ltest+Lcore-(ZY2 / 2).

[0067] The above-mentioned axial dimension measurement method is easy to operate. The bearing is directly pushed forward by the internal core rod and measured using a handheld universal measuring tool. The axial assembly dimension error prevention control effect can be achieved without the aid of complex equipment such as three-coordinate measuring instruments. The dimension chain calculation can be shortened, greatly reducing the difficulty of dimension calculation.

[0068] The present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or multiple times in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0069] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A rotor-stator axial dimension measuring tool is used to measure the axial dimension of the rotor-stator. The rotor-stator includes an intermediate casing rear mounting edge located at the end of the intermediate casing and a centering boss located on the shaft. The axial dimension of the rotor-stator is the axial distance from the intermediate casing rear mounting edge to the centering boss, and is characterized in that: The tooling includes: An external support frame, used to abut against the rear mounting edge of the intermediate casing; A core rod extends into the shaft cavity of the rotor and stator, and its tail end is used to abut against the centering boss; Wherein, the core rod is movably arranged on the external support frame, and also includes a measurement criterion surface close to the front end side.

2. The rotor-stator axial dimension measuring tool as claimed in claim 1, characterized in that: The centering boss is arranged on the fan shaft, and the tail end of the core rod is also provided with a spline for matching with the spline on the fan shaft.

3. The rotor-stator axial dimension measuring tool as claimed in claim 1, characterized in that: The tool also includes a clamping bolt connected to the front end of the core rod, and the clamping bolt is used to push the core rod to move axially.

4. The rotor-stator axial dimension measuring tool as claimed in claim 3, characterized in that: The tool also includes a force sensor arranged between the clamping bolt and the core rod.

5. The rotor-stator axial dimension measuring tool as claimed in claim 1, characterized in that: The external support frame is detachably fixed to the rear mounting edge of the intermediate casing by bolt fasteners.

6. A method for measuring the axial dimensions of a rotor and a stator, characterized in that: The rotor-stator axial dimension measuring tool as claimed in any one of claims 1 to 5 is used for measurement, and the method comprises the following steps: Place the outer support frame against the rear mounting edge of the intermediate casing; Insert the mandrel into the shaft cavity of the rotor and stator, and make the tail end of the mandrel butt against the centering boss; Apply axial force to the mandrel to push the fulcrum bearing to a forward push state; Measure the distance from the measuring datum surface of the mandrel to the rear mounting edge of the intermediate casing to obtain the length from the measuring datum surface of the mandrel to the tail end; Find the bearing clearance of the pivot bearing.

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