Design method of milling fixture for air inlet and outlet edge flashes of precisely-forged rotor blade

Abstract

The invention relates to the technical field of aero-engine blade machining, in particular to a design method of a precision forging rotor blade intake and exhaust edge flash milling clamp, which comprises the following steps: S1, determining a blade positioning point; s2, designing a blade body positioning structure; s3, designing a Z-axis positioning knot; s4, a journal positioning structure is designed, specifically, two V-shaped block assemblies are installed on the bottom plate, one V-shaped block assembly is used for supporting a lower journal of the blade, and the other V-shaped block assembly is used for supporting an upper journal of the blade; and S5, a pressing structure is designed, specifically, a support is installed on the bottom plate, and a plurality of pressing blocks are installed on the support and used for pressing the blade body and the shaft neck of the blade correspondingly. According to the milling clamp designed in the invention, six-point positioning is formed on the blade, and the requirement of spatial rotation or translation degree of freedom controlled by six positioning points of the blade is met.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing of aircraft engine blades, and in particular to a design method for a fixture for processing the flashing and milling of an intake and exhaust side of a precision forged rotor blade. Background Art

[0002] The characteristic of blade precision forging technology is that the blade body and the inner side of the tenon are forged without excess, which eliminates the subsequent CNC milling process of the blade body. The precision forging technology greatly improves the production efficiency of the blade, and the blade body does not require CNC milling, and the forging streamline is completely retained, which conforms to the anti-fatigue manufacturing concept, increases the strength and load-bearing capacity of the blade, and is beneficial to improving the fatigue life of the blade.

[0003] Figure 1 It is a schematic diagram of the flash of the precision forged blade body section. The precision forged blade blank has a 2mm flash allowance at the inlet and exhaust edges of the blade body. The dimensional tolerances of aq and ah of the finished blade are generally ±0.1mm. In order to meet the accuracy requirements of the subsequent process benchmark conversion, when milling the flash of the inlet and exhaust edges, the dimensional tolerances of aq and ah of the finished blade need to be compressed to 0-0.08mm. At the same time, the aq dimensional fluctuation of each section of the blade body is required to be no more than 0.06mm.

[0004] The precision forged blades are thin-walled parts and are easily deformed during clamping, resulting in unstable dimensions during intake and exhaust edge milling. In order to meet the high precision requirements of intake and exhaust edge milling and solve the problem of unstable dimensions during milling, it is urgently necessary to provide a design method for the intake and exhaust edge milling fixture for precision forged rotor blades. Summary of the invention

[0005] The main purpose of the present invention is to propose a design method for a precision forged rotor blade intake and exhaust edge milling fixture, aiming to solve the above technical problems.

[0006] To achieve the above object, the present invention proposes a design method for a precision forged rotor blade intake and exhaust milling fixture, comprising the following steps:

[0007] S1. Determine the blade positioning points: select six positioning points on the blade, numbered K1 to K6 in sequence, wherein positioning points K1 to K3 are located on the blade back profile, positioning point K4 is located on the inner surface of the blade tenon, and positioning points K5 and K6 are located on the lower journal and upper journal of the blade respectively;

[0008] S2. Design the blade positioning structure: install multiple support columns on the bottom plate, and the support columns are used to support the profile at the corresponding positions of the positioning points K1, K2, and K3 on the blade;

[0009] S3. Design a Z-axis positioning structure: install a Z-axis positioning pin on one of the support columns, and the Z-axis positioning pin is used to abut against the positioning point K4 on the inner surface of the tenon to form a Z-axis limit for the blade;

[0010] S4. Design the journal positioning structure: install two V-shaped block assemblies on the bottom plate, one of which is used to support the lower journal of the blade, and the other is used to support the upper journal of the blade;

[0011] S5. Design a clamping structure: install a bracket on the base plate, and install multiple clamps on the bracket to clamp the blade body and shaft neck of the blade respectively.

[0012] Preferably, the support column includes a first support column and a second support column; the Z-axis locating pin is installed on the second support column; a first protrusion is integrally formed at the top of the first support column, and the top profile of the first protrusion matches the blade back profile at the positioning point K3 on the blade; a second protrusion and a third protrusion are integrally formed at the top of the second support column; the top profiles of the second protrusion and the third protrusion respectively match the blade back profile at the positioning points K1 and K2 on the blade; the contours of the top profiles of the first protrusion, the second protrusion and the third protrusion are all quadrilateral shapes, and the side lengths are 4 to 6 mm.

[0013] Preferably, the V-shaped block assembly includes a base, a V-shaped block and a cover plate; the base is fixedly mounted on the bottom plate; a V-shaped groove is provided on the top of the V-shaped block; a vertical slide groove is provided on the front side of the base, and the V-shaped block is slidably mounted in the slide groove; the cover plate is mounted on the front side of the base by screws, and a cylindrical head screw is screwed on the cover plate to tighten the V-shaped block.

[0014] Preferably, a vertical waist-shaped hole is provided on the V-shaped block, and a spring is installed in the waist-shaped hole; a limit pin is inserted on the base, and the limit pin extends into the waist-shaped hole of the V-shaped block; the spring is always in a compressed state, and the upper end of the spring rests on the top wall of the waist-shaped hole; a notch is provided on the limit pin, and the lower end of the spring rests on the horizontal plane of the notch.

[0015] Preferably, the bracket includes a crossbeam and a pillar, and the two pillars are fixedly mounted on the top surface of the base plate near the two ends; the crossbeam is mounted on the top of the two columns; four clamping screws are screwed on the crossbeam; the pressure block includes a first pressure block, a second pressure block and two shaft neck pressure blocks respectively mounted on the four clamping screws; the first pressure block and the second pressure block are respectively used to clamp the blade body of the blade; the two shaft neck pressure blocks are respectively located directly above the two V-shaped block assemblies and are used to clamp the upper shaft neck and lower shaft neck of the blade.

[0016] Preferably, the first pressing block is located directly above the first supporting column; the second pressing block is located directly above the second supporting column; a fourth protrusion is integrally formed on the bottom surface of the first pressing block; the bottom profile of the fourth protrusion matches the blade basin profile corresponding to the positioning point K3 on the blade; a fifth protrusion and a sixth protrusion are integrally formed on the bottom surface of the second pressing block, and the bottom profiles of the fifth and sixth protrusions match the blade basin profiles corresponding to the positioning points K1 and K2 on the blade; the contours of the bottom profiles of the fourth, fifth and sixth protrusions are all quadrilateral shapes with side lengths of 4 to 6 mm.

[0017] Preferably, the second protrusion and the third protrusion on the top of the second supporting column are arranged at intervals to form a first groove; the fifth protrusion and the sixth protrusion on the bottom surface of the second pressing block are arranged at intervals to form a second groove.

[0018] Preferably, the clamping screw includes a screw section, a connecting column and a spherical body from top to bottom; the outer diameter of the connecting column is smaller than the diameter of the spherical body; a ball head mounting hole is arranged on the top surface of the shaft neck pressure block; the connecting column and the spherical body are inserted into the ball head mounting hole, and the spherical body is slidingly matched with the ball head mounting hole; a locking screw is screwed on the shaft neck pressure block, and the inner end of the locking screw is close to the outer cylindrical surface of the connecting column but not tightened.

[0019] Preferably, splitting grooves are respectively provided on the first pressure block and the second pressure block, and a ball head accommodating hole is provided at the lower end of the splitting groove; the spherical body is installed in the ball head accommodating hole, and the spherical body and the ball head accommodating hole are slidably matched; the connecting column is arranged in the splitting groove, and the groove width of the splitting groove is larger than the outer diameter of the connecting column; a pin is inserted on the crossbeam; limiting grooves are respectively provided on the side surfaces of the first pressure block and the second pressure block; the lower end of the pin extends into the limiting groove; there is a gap between the outer peripheral surface of the pin and the inner wall of the limiting groove.

[0020] Preferably, the portion where the Z-direction locating pin contacts the inner surface of the blade tenon is a hemispherical head structure.

[0021] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0022] (1) In the present invention, a plurality of support columns are installed on the bottom plate, and the support columns are used to support the profile at the positions corresponding to the positioning points K1, K2, and K3 on the blade; a Z-direction positioning pin is installed on one of the support columns, and the Z-direction positioning pin is used to abut against the positioning point K4 on the inner surface of the tenon to form a Z-direction limit for the blade; two V-shaped block assemblies are installed on the bottom plate, one of which is used to support the lower journal of the blade, and the other is used to support the upper journal of the blade; a bracket is installed on the bottom plate, and a plurality of pressing blocks are installed on the bracket to respectively press the blade body and journal of the blade. In the present invention, the designed milling fixture forms a six-point positioning for the blade, which meets the requirements of the spatial rotation or translation freedom controlled by the six positioning points of the blade.

[0023] (2) The milling fixture designed by the present invention has the Y-axis translation of the blade in the spatial freedom controlled by the first support column and the second support column for the positioning points K1, K2, and K3. In order to avoid over-positioning, the V-block is slidably installed in the slide groove, and a cylindrical head screw is screwed on the cover plate to tighten the V-block. That is, when the blade is clamped, after the blade is placed on the first support column and the second support column, the V-groove on the V-block is always in contact with the blade shaft neck under the action of the spring. The V-block is first locked with the cylindrical head screw, and then the shaft neck is pressed with the shaft neck pressure block. Therefore, the V-block is designed to be a movable structure in the Y-axis direction, so that the V-block can both effectively support the blade and avoid over-positioning.

[0024] (3) In the milling fixture designed in the present invention, the clamping screw is connected to the first clamping block, the second clamping block, and the journal clamping block using a spherical body, forming a follow-up connection structure. During the process of clamping the blade, each clamping block can swing around the X-axis and the Y-axis in a small range, so that the clamping surface can reliably contact the blade, thereby ensuring the reliability of blade clamping and avoiding micro-movement of the blade during flash milling.

[0025] (4) By adopting the milling fixture designed by the present invention to clamp the blades, inconsistent deformation of the precision forged blades due to over-positioning and micro-movement during the milling process due to unstable clamping, which makes the aq and ah dimensions of the intake and exhaust edges unqualified, is avoided. This is beneficial to ensure that the aq and ah dimensional tolerances are 0 to 0.08 mm, and the aq dimensional fluctuation of each section of the blade body is not greater than 0.06 mm. By using this fixture, the dimensional consistency after milling is good, which improves the milling quality of the intake and exhaust edges. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art 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 the structures shown in these drawings without paying creative work.

[0027] Figure 1 This is a schematic diagram of the flash edge of the blade section of the precision forged blade;

[0028] Figure 2 is a schematic diagram of six positioning points selected on the blade;

[0029] Figure 3 for Figure 1 Middle AA section view;

[0030] Figure 4 for Figure 1 Middle BB section view;

[0031] Figure 5 for Figure 1 Middle CC section view;

[0032] Figure 6 A front view of the milling fixture designed for the present invention;

[0033] Figure 7 A top view of the milling fixture designed for the present invention;

[0034] Figure 8 A three-dimensional structural diagram of the milling fixture designed for the present invention;

[0035] Fig. 9 It is a three-dimensional structural diagram of the V-shaped block assembly in the present invention;

[0036] Fig.10 A top view of a V-shaped block assembly of the present invention;

[0037] Fig.11 for Fig.10 Middle DD section view;

[0038] Fig.12 It is a structural schematic diagram of the base in the present invention;

[0039] Fig.13 It is a schematic diagram of the structural decomposition of the V-shaped block, the spring and the limit pin in the present invention;

[0040] Fig.14 It is a schematic diagram of the structural decomposition of the clamping screw and the journal pressing block in the present invention;

[0041] Fig.15It is a structural schematic diagram of the second supporting column in the present invention;

[0042] Fig.16 It is a structural schematic diagram of the assembly of the second pressing block, the pressing screw and the pin in the present invention;

[0043] Fig.17 It is a structural schematic diagram of the first supporting column in the present invention;

[0044] Fig.18 It is a structural schematic diagram of the assembly of the first pressing block, the clamping screw and the pin in the present invention.

[0045] Explanation of the accompanying drawings: 1. bottom plate; 2. pillar; 3. crossbeam; 4. base; 5. V-shaped block; 5a. V-shaped groove; 5b. waist-shaped hole; 6. cover plate; 7. cylindrical head screw; 8. limit pin; 8a. notch; 9. spring; 10. first supporting column; 10a. first protrusion; 11. second supporting column; 11a. second protrusion; 11b. third protrusion; 11c. first groove; 12. Z-direction locating pin; 13. clamping screw; 13a. screw segment; 13b. spherical body; 13c. connecting column; 14. first pressure block; 14a. fourth protrusion; 15. second pressure block; 15a. fifth protrusion; 15b. sixth protrusion; 16. journal pressure block; 16a. ball head mounting hole; 17. limit screw; 18. split groove; 19. ball head receiving hole; 20. pin; 21. limit groove. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0048] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0049] As shown in the accompanying drawings, a design method for a precision forged rotor blade intake and exhaust milling fixture includes the following steps:

[0050] S1. Determine the blade positioning points: select six positioning points on the blade, numbered K1 to K6 in sequence, wherein positioning points K1 to K3 are located on the blade back profile, positioning point K4 is located on the inner surface of the blade tenon, and positioning points K5 and K6 are located on the lower journal and upper journal of the blade respectively;

[0051] S2. Design the blade body positioning structure: install multiple support columns on the bottom plate 1, and the support columns are used to support the profile at the corresponding positions of the positioning points K1, K2, and K3 on the blade;

[0052] S3. Design a Z-axis positioning structure: install a Z-direction positioning pin 12 on one of the support columns, and the Z-direction positioning pin 12 is used to abut against the positioning point K4 on the inner surface of the tenon to form a Z-direction limit for the blade;

[0053] S4. Design the journal positioning structure: install two V-shaped block assemblies on the bottom plate 1, wherein one V-shaped block assembly is used to support the lower journal of the blade, and the other V-shaped block assembly is used to support the upper journal of the blade;

[0054] S5. Design a clamping structure: install a bracket on the base plate 1, and install a plurality of clamping blocks on the bracket to respectively clamp the blade body and the shaft neck of the blade.

[0055] Combination Figures 2 to 5 As shown, in the blade coordinate system, according to the forging structure, the coordinates of the positioning point K1 on the blade body are (8, -0.452, 13.8), the coordinates of the positioning point K2 are (-7, 0.969, 13.8), and the coordinates of the positioning point K3 are (0, 1.55, 38.8). The coordinates of the positioning point K4 on the inner surface of the blade tenon are (3, 5, 7.84), the coordinates of the positioning point K5 at the lower journal are (0, 4, -6.2), and the coordinates of the positioning point K6 at the upper journal are (0, 4.5, 56.8).

[0056] Combination Figure 6 , Fig.15 and Fig.17 As shown, the support column includes a first support column 10 and a second support column 11; the Z-direction locating pin 12 is installed on the second support column 11; a first protrusion 10a is integrally formed at the top end of the first support column 10, and the top profile of the first protrusion 10a matches the blade back profile at the positioning point K3 on the blade; a second protrusion 11a and a third protrusion 11b are integrally formed at the top end of the second support column 11; the top profiles of the second protrusion 11a and the third protrusion 11b respectively match the blade back profile at the positioning points K1 and K2 on the blade; when the blade is clamped, the first protrusion 10a is supported on the profile at the blade back positioning point K3, and the second protrusion 11a and the third protrusion 11b are respectively supported on the profiles at the positioning points K1 and K2 on the blade back. Specifically, the top profiles of the first protrusion 10a, the second protrusion 11a, and the third protrusion 11b are designed in the shape of a blade back, and the contours of the top profiles are all quadrilateral with a side length of 4 to 6 mm, so that the top profiles of the first protrusion 10a, the second protrusion 11a, and the third protrusion 11b form a small area surface contact with the blade back.

[0057] Combination Figures 9 to 13 As shown, the V-shaped block assembly includes a base 4, a V-shaped block 5 and a cover plate 6; the base 4 is fixedly mounted on the bottom plate 1; a V-shaped groove 5a is arranged on the top of the V-shaped block 5; a vertical slide groove 4a is arranged on the front of the base 4, and the V-shaped block 5 is slidably mounted in the slide groove 4a; the cover plate 6 is mounted on the front of the base 4 by screws, and a cylindrical head screw 7 is screwed on the cover plate 6 for tightening the V-shaped block 5. Further, a vertical waist-shaped hole 5b is arranged on the V-shaped block 5, and a spring 9 is installed in the waist-shaped hole 5b; a limit pin 8 is inserted on the base 4, and the limit pin 8 extends into the waist-shaped hole 5b of the V-shaped block 5; the spring 9 is always in a compressed state, and the upper end of the spring 9 abuts against the top wall of the waist-shaped hole 5b; a notch 8a is opened on the limit pin 8, and the lower end of the spring 9 abuts against the horizontal surface of the notch 8a. The spring 9 always exerts an upward force on the V-shaped block 5, pushing the V-shaped block 5 to always abut against the journal of the blade.

[0058] Since the Y-axis translation of the blade in the spatial freedom is controlled by the first support column 10 and the second support column 11 for the positioning points K1, K2, and K3, in order to avoid over-positioning, the V-block 5 is designed as a movable structure in the Y-axis direction, so that the V-block 5 can both effectively support the blade and avoid over-positioning. The specific clamping operation process is as follows: After the blade is placed on the first support column 10 and the second support column 11, the blade body is first pressed by the pressure block corresponding to the blade body. At this time, under the action of the spring 9, the V-groove 5a on the V-block 5 is always in contact with the blade journal. The V-block 5 is first locked with the cylindrical head screw 7, and then the journal is pressed. In this embodiment, the thickness of the plate body where the V-groove 5a is located is 2 to 3 mm, and the V-groove 5a forms a line contact with the cylindrical surface of the upper journal and the lower journal.

[0059] Combination Figure 8 , Figure 18 to Figure 18 As shown, the bracket includes a crossbeam 3 and a support 2, and the two support 2 are fixedly installed on the top surface of the bottom plate 1 near the two ends; the crossbeam 3 is mounted on the top of the two columns 2; four clamping screws 13 are screwed on the crossbeam 3; the pressure block includes a first pressure block 14, a second pressure block 15 and two journal pressure blocks 16 respectively installed on the four clamping screws 13; the first pressure block 14 and the second pressure block 15 are respectively used to clamp the blade body of the blade; the two journal pressure blocks 16 are respectively located directly above the two V-shaped block assemblies and are used to clamp the upper journal and lower journal of the blade. By rotating the clamping screw 13, the clamping screw 13 can drive the corresponding pressure block to clamp the blade while descending.

[0060] Furthermore, the first pressing block 14 is located directly above the first supporting column 10; the second pressing block 15 is located directly above the second supporting column 11; a fourth protrusion 14a is integrally formed on the bottom surface of the first pressing block 14; the bottom profile of the fourth protrusion 14a matches the blade basin profile corresponding to the positioning point K3 on the blade; a fifth protrusion 15a and a sixth protrusion 15b are integrally formed on the bottom surface of the second pressing block 15, and the bottom profiles of the fifth protrusion 15a and the sixth protrusion 15b match the blade basin profile corresponding to the positioning points K1 and K2 on the blade; in order to reduce the contact surface area between the first pressing block 14 and the second pressing block 15 and the blade, the contours of the bottom profiles of the fourth protrusion 14a, the fifth protrusion 15a and the sixth protrusion 15b are designed to be quadrilateral shapes with a side length of 4 to 6 mm. Furthermore, the second protrusion 11a and the third protrusion 11b on the top of the second support column 11 are arranged at intervals to form a first groove 11c; the fifth protrusion 15a and the sixth protrusion 15b on the bottom surface of the second pressing block 15 are arranged at intervals to form a second groove 15c. The first groove 11c and the second groove 15c are used to reduce the contact area with the blade.

[0061] In this embodiment, the clamping screw 13 includes a screw segment 13a, a connecting column 13c and a spherical body 13b from top to bottom; the outer diameter of the connecting column 13c is smaller than the diameter of the spherical body 13b; a ball head mounting hole 16a is provided on the top surface of the shaft neck pressure block 16; the connecting column 13c and the spherical body 13b are inserted into the ball head mounting hole 16a, and the spherical body 13b is slidably matched with the ball head mounting hole 16a; a set screw 17 is screwed on the shaft neck pressure block 16, and the inner end of the set screw 17 is close to the outer cylindrical surface of the connecting column 13c but not tightened. Furthermore, a splitting groove 18 is respectively provided on the first pressing block 14 and the second pressing block 15, and a ball head receiving hole 19 is provided at the lower end of the splitting groove 18; the spherical body 13b is installed in the ball head receiving hole 19, and the spherical body 13b is slidably matched with the ball head receiving hole 19; the connecting column 13c is arranged in the splitting groove 18, and the groove width of the splitting groove 18 is greater than the outer diameter of the connecting column 13c; a pin 20 is inserted into the crossbeam 3; a limiting groove 21 is respectively provided on the side surface of the first pressing block 14 and the second pressing block 15; the lower end of the pin 20 extends into the limiting groove 21; there is a gap between the outer peripheral surface of the pin 20 and the inner wall of the limiting groove 21.

[0062] By adopting the above structure, a follow-up connection structure is formed between the clamping screw 13 and each clamping block. In the process of clamping the blade, each clamping block can swing in a small range around the X-axis and the Y-axis, so that the clamping surface can reliably contact the blade, thereby ensuring the reliability of blade clamping and avoiding micro-movement of the blade during flash milling.

[0063] Combination Figure 6 As shown, the part where the Z-direction positioning pin 12 contacts the inner surface of the blade tenon is a hemispherical head structure, and the hemispherical surface is tangent to the inner surface of the blade tenon to form a point contact, and the contact point is the positioning point K4.

[0064] In this embodiment, the first support column 10, the second support column 11, the first pressure block 14, the second pressure block 15, the shaft neck pressure block 16 and the V-shaped block 5 are all made of aluminum alloy 2A12 material, and the remaining clamp materials are made of tempered 45 steel material, which can not only ensure the strength of the clamp structure but also avoid crushing the blade surface.

[0065] In this embodiment, the base 4, the first supporting column 10, the second supporting column 11, and the pillar 2 are all fixedly mounted on the bottom plate 1 by means of positioning pins and screws, and the pillar 2 and the crossbeam 3 are also fastened and connected by means of positioning pins and screws.

[0066] In this embodiment, the principle of six-point positioning is as follows: positioning points K1, K2, and K3 control the rotation around the X-axis and around the Z-axis and the translation along the Y-axis in the spatial freedom of the blade, and are the main reference for blade positioning. The Z-direction positioning pin 12 corresponds to the positioning point K4 on the inner surface of the tenon. Because the blade is subjected to very little force in the Z direction during milling, the Z-direction positioning pin 12 is designed to contact the blade in a hemispherical shape, and is in point contact with the blade, which can ensure the positioning accuracy of the blade and achieve the purpose of controlling the translation of the Z axis in the spatial freedom of the blade. The two V-shaped block assemblies correspond to the upper journal positioning point K6 and the lower journal positioning point K5 of the blade, respectively. Because the translation of the Y axis in the spatial freedom of the blade is controlled by the positioning points K1, K2, and K3, the V-shaped block 5 in the V-shaped block assembly is designed as a movable structure in the Y-axis direction to avoid over-positioning. The upper journal positioning point K6 and the lower journal positioning point K5 control the rotation around the Y axis and the translation along the X axis in the spatial freedom of the blade. In summary, the positioning structure of the fixture completely restricts the six degrees of freedom of the blade space (rotation around the XYZ axes and translation along the XYZ axes) according to the six-point positioning of the blade to achieve the positioning effect.

[0067] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A design method for a precision forged rotor blade intake and exhaust milling fixture, characterized in that: The steps include: S1. Determine the blade positioning points: select six positioning points on the blade, numbered K1 to K6 in sequence, wherein positioning points K1 to K3 are located on the blade back profile, positioning point K4 is located on the inner surface of the blade tenon, and positioning points K5 and K6 are located on the lower journal and upper journal of the blade respectively; S2. Designing a blade body positioning structure: installing a plurality of support columns on the base plate (1), the support columns being used to support the profile at positions corresponding to the positioning points K1, K2, and K3 on the blade; S3. Design a Z-axis positioning structure: install a Z-direction positioning pin (12) on one of the support columns, the Z-direction positioning pin (12) is used to abut against a positioning point K4 on the inner surface of the tenon to form a Z-direction limit for the blade; S4. Designing a journal positioning structure: installing two V-shaped block assemblies on the bottom plate (1), wherein one V-shaped block assembly is used to support the lower journal of the blade, and the other V-shaped block assembly is used to support the upper journal of the blade; S5. Design a clamping structure: install a bracket on the base plate (1), and install a plurality of clamping blocks on the bracket to respectively clamp the blade body and the shaft neck of the blade.

2. The design method of a precision forged rotor blade intake and exhaust edge milling fixture as claimed in claim 1, characterized in that: The support column comprises a first support column (10) and a second support column (11); the Z-direction positioning pin (12) is installed on the second support column (11); A first protrusion (10a) is integrally formed at the top end of the first supporting column (10), and the top profile of the first protrusion (10a) matches the back profile of the blade at the positioning point K3 on the blade; a second protrusion (11a) and a third protrusion (11b) are integrally formed at the top end of the second supporting column (11); the top profiles of the second protrusion (11a) and the third protrusion (11b) respectively match the back profiles of the blade at the positioning points K1 and K2 on the blade; The top profiles of the first protrusion (10a), the second protrusion (11a) and the third protrusion (11b) are all in a quadrilateral shape, and the side length is 4 to 6 mm.

3. The design method of a precision forged rotor blade intake and exhaust edge milling fixture as claimed in claim 1, characterized in that: The V-shaped block assembly comprises a base (4), a V-shaped block (5) and a cover plate (6); the base (4) is fixedly mounted on the bottom plate (1); a V-shaped groove (5a) is arranged on the top of the V-shaped block (5); a vertical slide groove (4a) is arranged on the front of the base (4), and the V-shaped block (5) is slidably mounted in the slide groove (4a); the cover plate (6) is mounted on the front of the base (4) by means of screws, and a cylindrical head screw (7) is screwed on the cover plate (6) for tightening the V-shaped block (5).

4. The design method of a precision forged rotor blade intake and exhaust edge milling fixture as claimed in claim 3, characterized in that: A vertical waist-shaped hole (5b) is provided on the V-shaped block (5), and a spring (9) is installed in the waist-shaped hole (5b); a limit pin (8) is inserted on the base (4), and the limit pin (8) extends into the waist-shaped hole (5b) of the V-shaped block (5); the spring (9) is always in a compressed state, and the upper end of the spring (9) abuts against the top wall of the waist-shaped hole (5b); a notch (8a) is provided on the limit pin (8), and the lower end of the spring (9) abuts against the horizontal surface of the notch (8a).

5. The design method of a precision forged rotor blade intake and exhaust edge milling fixture as claimed in claim 2, characterized in that: The bracket comprises a crossbeam (3) and a support column (2), wherein the two support columns (2) are respectively fixedly mounted on the top surface of the base plate (1) near the two ends; the crossbeam (3) is mounted on the top of the two upright columns (2); and four clamping screws (13) are screwed on the crossbeam (3); The pressing block comprises a first pressing block (14), a second pressing block (15) and two journal pressing blocks (16) respectively mounted on four clamping screws (13); the first pressing block (14) and the second pressing block (15) are respectively used for clamping the blade body of the blade; the two journal pressing blocks (16) are respectively located directly above the two V-shaped block assemblies and are used for clamping the upper journal and the lower journal of the blade.

6. The design method of a precision forged rotor blade intake and exhaust edge milling fixture as claimed in claim 5, characterized in that: The first pressing block (14) is located directly above the first supporting column (10); the second pressing block (15) is located directly above the second supporting column (11); A fourth protrusion (14a) is integrally formed on the bottom surface of the first pressing block (14); the bottom profile of the fourth protrusion (14a) matches the blade basin profile corresponding to the positioning point K3 on the blade; A fifth protrusion (15a) and a sixth protrusion (15b) are integrally formed on the bottom surface of the second pressing block (15), and the bottom profiles of the fifth protrusion (15a) and the sixth protrusion (15b) match the blade basin profiles corresponding to the positioning points K1 and K2 on the blade; The bottom profiles of the fourth protrusion (14a), the fifth protrusion (15a) and the sixth protrusion (15b) are all in a quadrilateral shape, and the side length is 4 to 6 mm.

7. The method for designing a fixture for machining the flash and edge milling of the precision forged rotor blades as claimed in claim 6, characterized in that: The second protrusion (11a) and the third protrusion (11b) on the top of the second supporting column (11) are arranged at intervals to form a first groove (11c); the fifth protrusion (15a) and the sixth protrusion (15b) on the bottom surface of the second pressing block (15) are arranged at intervals to form a second groove (15c).

8. The method for designing a fixture for machining the flash and milling of the inlet and exhaust edges of precision forged rotor blades as claimed in claim 5, characterized in that: The compression screw (13) comprises, from top to bottom, a screw rod section (13a), a connecting column (13c) and a spherical body (13b); the outer diameter of the connecting column (13c) is smaller than the diameter of the spherical body (13b); A ball head mounting hole (16a) is provided on the top surface of the shaft neck pressure block (16); the connecting column (13c) and the spherical body (13b) are inserted into the ball head mounting hole (16a), and the spherical body (13b) and the ball head mounting hole (16a) are slidably matched; a set screw (17) is screwed on the shaft neck pressure block (16), and the inner end of the set screw (17) is close to the outer cylindrical surface of the connecting column (13c) but not pressed tightly.

9. The design method of a precision forged rotor blade intake and exhaust edge milling fixture as claimed in claim 8, characterized in that: The first pressing block (14) and the second pressing block (15) are respectively provided with split grooves (18), and the lower ends of the split grooves (18) are provided with ball head receiving holes (19); The spherical body (13b) is installed in the ball head receiving hole (19), and the spherical body (13b) and the ball head receiving hole (19) are slidably matched; the connecting column (13c) is arranged in the splitting groove (18), and the groove width of the splitting groove (18) is greater than the outer diameter of the connecting column (13c); A pin (20) is inserted into the crossbeam (3); limiting grooves (21) are respectively provided on the side surfaces of the first pressing block (14) and the second pressing block (15); the lower end of the pin (20) extends into the limiting groove (21); and a gap exists between the outer peripheral surface of the pin (20) and the inner wall of the limiting groove (21).

10. The method for designing a fixture for precision forging rotor blade intake and exhaust milling according to claim 1, characterized in that: The portion where the Z-direction positioning pin (12) contacts the inner surface of the blade tenon is a hemispherical head structure.

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