Fixture for measuring blade with hole on mounting plate and measuring method

Abstract

The invention discloses a clamp for measuring a mounting plate perforated blade and a measuring method, and mainly relates to a three-coordinate clamp and a standard component for measuring a blade body profile of the mounting plate perforated blade, and the clamp comprises a base, a supporting seat, a pressing block, a positioning base, a positioning block, a positioning pin and a pressing bolt. Wherein the height of the positioning pin is 1 / 3 of the blade height of the to-be-measured blade, and the positioning pin is a standard component used for establishing a coordinate system during three-coordinate measurement. The measuring method comprises the following steps: S1, clamping a blade; s2, establishing a coordinate system; s3, compiling a measurement program; and S36, measuring and evaluating the blade. According to the invention, the three-coordinate clamp and the standard component are integrated, so that on the premise of ensuring the same measurement effect, the manufacturing difficulty of the blade standard component can be reduced, and the cost and the period of additionally manufacturing a single three-coordinate measurement standard component are greatly reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of aero-engine processing, and in particular relates to a fixture and a measuring method for measuring a blade with a hole on a mounting plate. Background Art

[0002] The blades of aircraft engines and gas turbines are mostly processed by one or a combination of methods such as precision forging, precision casting, precision electrolysis, rolling or CNC machining to obtain a blade body profile with no or small allowance. With the increasing requirements for the processing accuracy of blades, and the complex spatial curved surface structure of the blade profile, the measurement of the size and position accuracy after processing often requires contact measurement methods (such as three-dimensional coordinate measuring machines) for detection. Before three-dimensional measurement, the measurement coordinate system needs to be calibrated with standard parts to ensure the stability and accuracy of the measurement.

[0003] For contact measurement methods, during the measurement process, it is often necessary to manufacture standard parts for adjusting and calibrating the theoretical position or coordinate system of the measuring equipment. Therefore, the accuracy of blade standard parts is much higher than that of batch processed blades. Such standard parts have a long production cycle, are difficult to manufacture, and have high manufacturing costs.

[0004] Chinese invention patent with publication number CN116608807A discloses a standard part for measuring air film holes of high-pressure turbine blades, which can objectively evaluate air film holes with complex spatial distribution; Chinese invention patent with publication number CN101949680A discloses a design method for a blade standard part for surface measurement, which can solve the problem of blade measurement in optical projectors and inductance meters by simplifying the complex blade surface into a plate-like structure or a stepped structure; Chinese invention patent with publication number CN112197723A discloses a calibration standard sample and method in which a simulated workpiece and a standard ball are placed in one body, but the manufacturing difficulty of the standard sample is greater than that of a general workpiece, and it is difficult to promote and apply; Chinese invention patent with publication number CN116475788A discloses a stator blade standard part and processing method, and Chinese invention patent with publication number CN109746797A discloses a processing method for a standard part for arc tooth blades, both of which have high manufacturing costs and long processing cycles. Summary of the invention

[0005] In order to solve the above problems, the present invention aims to provide a fixture and a measuring method for measuring blades with holes in a mounting plate.

[0006] In order to achieve the above-mentioned object, the present invention adopts the following technical scheme: a fixture for measuring blades with holes on a mounting plate, comprising a base, a support seat is installed on the upper end surface of the base, a positioning base and a positioning block are installed on the support seat, and a clamping block is also fixed to the side end of the support seat by a clamping screw;

[0007] The positioning base is provided with a positioning pin, the positioning surface and the top surface of the positioning block are perpendicular to each other, a groove is provided in the positioning surface, and the clamping block, the positioning surface and the positioning base constitute a clamping area.

[0008] Preferably, the positioning block is a rectangular block, a groove is provided at a side end of the positioning block, positioning bases are respectively provided at both ends of the positioning block, and a positioning pin is provided on the positioning base at one end.

[0009] Preferably, a vertical groove is provided on the side surface of the support seat, and a threaded hole is provided in the groove.

[0010] Preferably, the clamping block is in an "L" shape, with a threaded hole on its long end, and a clamping screw fixes the clamping block in a groove formed in the support seat, and the short end extends out of the groove and faces the groove formed in the positioning surface of the positioning block.

[0011] Preferably, the positioning base and the positioning pin are both cylindrical, the diameter of the positioning pin is smaller than the positioning base, and the central axes of the two are on the same vertical line.

[0012] A method for measuring a blade with a hole in a mounting plate comprises the following steps:

[0013] Step 1: Clamp the blade, put the mounting hole of the blade to be measured into the positioning pin, the blade to be measured is close to the positioning surface of the positioning block, and at the same time, a force is applied from the positioning pin to the positioning base on the other side of the blade to make the mounting hole of the blade to be measured and the positioning pin in a tangent state. At this time, tighten the clamping bolt so that the positioning surface of the clamping block is close to the mounting plate of the blade to be measured, thereby completing the clamping of the blade to be measured;

[0014] Step 2: Establish a coordinate system, take points on the cylindrical locating pin, locating surface, and locating base, and establish a coordinate system including the X-axis, Y-axis, and Z-axis in the three-coordinate measurement software;

[0015] Step 3: Prepare a measurement program, import the theoretical three-dimensional model of the blade with holes on the mounting plate into the three-dimensional coordinate measurement software, and prepare a measurement program according to the characteristic parameter requirements of the blade to be measured;

[0016] Step 4: Measurement and evaluation. Start the three-dimensional coordinate measuring machine and compare the data measured in step 2 with the reference value. If the error is within the allowable range, it means that the three-dimensional coordinate measuring machine is in normal condition and batch measurement can be carried out. The measured data is fitted and evaluated, and the blades that meet the requirements are qualified.

[0017] The height of the locating pin is 1 / 3 of the height of the blade to be measured, and it is a standard part used to establish the coordinate system during three-coordinate measurement.

[0018] Preferably, step 2 is specifically as follows: points are taken on the cylindrical locating pin to obtain the central axis of the cylinder, points are taken on the locating surface of the locating block and the top surface of the locating base respectively, and then the central axis of the cylinder is offset by X0 to determine the X and Y axes; points are taken on the top surface of the locating pin to determine the Z axis, thereby establishing a coordinate system including the X axis, Y axis and Z axis in the three-coordinate measurement software.

[0019] Preferably, the characteristic parameters of step 3 are at least two of the blade basin and blade back contour, leading and trailing edge thickness, blade body thickness, leading and trailing edge position, chord width, overlap point position, curvature, torsion, parallelism, and verticality.

[0020] Compared with the prior art, the present invention has the following advantages: the present invention provides a device and a measuring method that integrates a fixture and a standard part for measuring a blade with a hole on a mounting plate, which can significantly shorten the production cycle and greatly reduce the difficulty and cost of manufacturing standard parts. The present invention can also be promoted and applied in the design of standard parts for similar blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the blade measuring fixture with a mounting plate and a hole in the present invention;

[0023] Figure 2 It is a schematic diagram of the tangent state between the mounting hole of the blade to be tested and the standard part and the coordinate system;

[0024] Figure 3 A front view of the blade clamping part of the present invention

[0025] Figure 4 for Figure 2 Top view

[0026] In the figure, 1-base, 2-support base, 3-positioning base, 4-positioning pin, 5-positioning block, 501-positioning surface, 502-top surface, 6-clamping block, 7-clamping bolt. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to the common technical knowledge and customary means in the field are included in the scope of the present invention.

[0028] Reference Figure 1 The present invention provides a fixture and standard parts for measuring blades with holes in a mounting plate, comprising a base 1, a support base 2, a clamping block 6, a positioning base 3, a positioning block 5, a positioning pin, i.e., a standard part 4, and a clamping bolt 7. The base 1, the support base 2, the positioning base 3, and the positioning block 5 are connected in sequence, the positioning pin, i.e., the standard part 4 is fixed to the positioning base 3, and the clamping block 6 is connected to the support base 2 through the clamping bolt 7. The positioning base 3 is provided with a positioning pin 4, the positioning surface 501 and the top surface 502 of the positioning block 5 are perpendicular to each other, a groove is provided in the positioning surface 501, and the clamping block 6, the positioning surface 501, and the positioning base 3 constitute a clamping area.

[0029] The positioning block 5 is a rectangular block, with a groove provided on the side end of the positioning block 5, and positioning bases 3 are provided at both ends of the positioning block 5, respectively, and a positioning pin 4 is provided on the positioning base 3 at one end. A vertical groove is provided on the side of the support seat 2, and a threaded hole is provided in the groove. The clamping block 6 is in an "L" shape, with a threaded hole provided on the long end thereof, and the clamping screw 7 fixes the clamping block 6 in the groove provided in the support seat 2, and the short end extends out of the groove and faces the groove provided on the positioning surface 501 of the positioning block 5. Both the positioning base 3 and the positioning pin 4 are cylindrical, and the diameter of the positioning pin 4 is smaller than that of the positioning base 3, and the central axes of the two are on the same vertical line.

[0030] The machining positioning point of the blade with hole of the mounting plate to be measured is consistent with that when it is clamped on the positioning pin, that is, the standard part 4. The present invention also provides a measurement method for measuring the blade with hole of the mounting plate.

[0031] The steps include:

[0032] S1. Clamping the blade: insert the positioning pin, i.e., the standard part 4, into the mounting hole of the blade to be measured from top to bottom, close to the positioning surface 501 of the positioning block 5, and at the same time give the blade a force from the positioning pin, i.e., the standard part 4 to the other side of the positioning base 3, so that the mounting hole of the blade to be measured and the positioning pin, i.e., the standard part 4 are in a tangent state. At this time, tighten the clamping bolt 7 so that the positioning surface 501 of the clamping block 5 is close to the mounting plate of the blade to be measured, thereby completing the clamping of the blade to be measured.

[0033] S2. Establish coordinate system: see Figure 2 , take points on the cylindrical locating pin 4 to obtain the central axis of the cylinder, take points on the locating surface 501 of the locating block 5 and the top surface of the locating base respectively, and then offset the central axis of the cylinder by X0 to determine the X and Y axes; take points on the top surface of the (locating pin) standard part 4 to determine the Z axis, thereby establishing a coordinate system including the X axis, Y axis and Z axis in the three-dimensional coordinate measurement software.

[0034] S3, compiling a measurement program: importing the theoretical three-dimensional model of the blade with holes in the mounting plate into the three-coordinate measurement software, and compiling a measurement program according to the characteristic parameter requirements of the blade to be measured. Further, the characteristic parameters are at least two of the blade basin and blade back contour, leading and trailing edge thickness, blade body thickness, leading and trailing edge position, chord width, overlap point position, bend, torsion, parallelism, and verticality.

[0035] S4, measurement and evaluation: Start the three-dimensional coordinate measuring machine, take points on the positioning surface 501, the top surface 502 and the positioning pin, i.e. the standard part 4, on the positioning block in S2, and compare the measured data with the reference value, i.e. the theoretical value of the blade body profile. If the error is within the allowable range, it means that the three-dimensional coordinate measuring machine is in normal condition and batch measurement can be carried out. Perform fitting evaluation on the measured data, and adopt overall fitting. The blades that are smooth and meet the requirements are qualified.

[0036] The above is a detailed introduction to a fixture and a measuring method for measuring blades with holes in a mounting plate provided by the present invention. This article uses specific examples to illustrate the structure and working principle of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A fixture for measuring blades with holes on mounting plates, characterized in that: It comprises a base (1), a support base (2) is installed on the upper end surface of the base (1), a positioning base (3) and a positioning block (5) are installed on the support base (2), and a clamping block (6) is fixed on the side end of the support base (2) by a clamping screw (7); The positioning base (3) is provided with a positioning pin (4); the positioning surface (501) and the top surface (502) of the positioning block (5) are perpendicular to each other; a groove is provided in the positioning surface (501); and the clamping block (6), the positioning surface (501) and the positioning base (3) together constitute a clamping area.

2. The fixture for measuring blades with holes in mounting plates according to claim 1 is characterized in that: The positioning block (5) is a rectangular block, a groove is provided at the side end of the positioning block (5), positioning bases (3) are respectively provided at both ends of the positioning block (5), and a positioning pin (4) is provided on the positioning base (3) at one end.

3. The fixture for measuring blades with holes in mounting plates according to claim 1, characterized in that: A vertical groove is provided on the side of the support seat (2), and a threaded hole is provided in the groove.

4. The fixture for measuring blades with holes in mounting plates according to claim 1, characterized in that: The clamping block (6) is in an "L" shape, with a threaded hole on its long end. The clamping screw (7) fixes the clamping block (6) in a groove formed in the support seat (2), and the short end extends out of the groove and faces the groove formed in the positioning surface (501) of the positioning block (5).

5. The fixture for measuring blades with holes in mounting plates according to claim 1, characterized in that: The positioning base (3) and the positioning pin (4) are both cylindrical, the diameter of the positioning pin (4) is smaller than that of the positioning base (3), and the central axes of the two are on the same vertical line.

6. A method for measuring a blade with a hole in a mounting plate using the fixture according to any one of claims 1 to 5, characterized in that: The following steps are included: Step 1: Clamp the blade, place the mounting hole of the blade to be measured into the positioning pin (4), and make the blade to be measured close to the positioning surface (501) of the positioning block (5). At the same time, give the blade a force from the positioning pin (4) to the other side positioning base (3), so that the mounting hole of the blade to be measured and the positioning pin (4) are in a tangent state. At this time, tighten the clamping bolt (7) so that the positioning surface (501) of the clamping block (5) is close to the mounting plate of the blade to be measured, thereby completing the clamping of the blade to be measured; Step 2: Establish a coordinate system, respectively take points on the cylindrical positioning pin (4), the positioning surface (501), and the positioning base (3), and establish a coordinate system including the X-axis, the Y-axis, and the Z-axis in the three-coordinate measurement software; Step 3: Prepare a measurement program, import the theoretical three-dimensional model of the blade with holes on the mounting plate into the three-dimensional coordinate measurement software, and prepare a measurement program according to the characteristic parameter requirements of the blade to be measured; Step 4: Measurement and evaluation. Start the three-dimensional coordinate measuring machine and compare the data measured in step 2 with the reference value. If the error is within the allowable range, it means that the three-dimensional coordinate measuring machine is in normal condition and batch measurement can be carried out. The measured data is fitted and evaluated, and the blades that meet the requirements are qualified.

7. The method for measuring blades with holes in a mounting plate according to claim 6, characterized in that: The height of the locating pin is 1 / 3 of the height of the blade to be measured, and it is a standard part used to establish the coordinate system during three-coordinate measurement.

8. The method for measuring a blade with a hole in a mounting plate according to claim 6 or 7, characterized in that: The specific steps of step 2 are as follows: points are collected on the cylindrical locating pin (4) to obtain the central axis of the cylinder; points are collected on the locating surface (501) of the locating block (5) and the top surface of the locating base respectively; and then the central axis of the cylinder is offset by X0 to determine the X and Y axes; points are collected on the top surface of the standard part, i.e. the locating pin (4), to determine the Z axis, thereby establishing a coordinate system including the X axis, the Y axis and the Z axis in the three-coordinate measurement software.

9. The method for measuring blades with holes in a mounting plate according to claim 6, characterized in that: The characteristic parameters of step 3 are at least two of the blade basin and blade back contour, leading and trailing edge thickness, blade body thickness, leading and trailing edge position, chord width, overlap point position, curvature, torsion, parallelism, and verticality.

Images