Novel method for machining tail blade lock notch groove through planing and slotting machine

Abstract

The invention discloses a novel method for machining a last blade lock notch groove through a planing and slotting machine, relates to the technical field of machining of rhombic lock notch grooves of steam turbine rotors, and aims to solve the problems that according to an existing last blade lock notch groove method, when an acute angle is machined, a tool is prone to breakage, so that the lock notch groove is punctured, and the perpendicularity of the lock notch groove is poor. The method comprises the following steps that firstly, a to-be-machined lock notch rhombus and quadrilateral CAD drawing is drawn and comprises to-be-machined parts at the left end and the right end of a lock notch and a feed space, and each to-be-machined part is divided into an acute triangle part, a rectangular part and an obtuse triangle part; 2, a tool is selected, and a rough slotting tool is selected as the tool; the machining method is used for machining the locking groove of the tail blade of the steam turbine rotor, the machining allowance is sequentially reduced through rough machining, semi-finish machining and finish machining, the machining efficiency is ensured, and the possibility that the cutter is broken when the acute angle is machined is also prevented.

Description

Technical Field

[0001] The invention relates to the technical field of processing diamond-shaped locking grooves of steam turbine rotors, and in particular to a method for processing locking grooves of last blades using a novel planing and slotting machine. Background Art

[0002] The blade lock groove at the end of the inverted trapezoidal blade root groove of the turbine rotor is generally a diamond quadrilateral structure, which is usually processed by a planing machine. When processing on a CNC planing machine, it is necessary to select a suitable slotting tool according to the acute angle and obtuse angle of the diamond quadrilateral lock groove, and then compile a special CNC program for processing according to the size of the lock groove. The diamond quadrilateral lock groove has a pair of obtuse angles and a pair of acute angles. In order to process it into the required angle, a diamond quadrilateral slotting tool with the same angle is required to be used for processing to ensure the angle of the quadrilateral lock groove after processing.

[0003] However, when the tool processes the diamond-shaped sharp-angled part of the locking groove, due to the thin structure and poor strength of the tool tip and the concentrated cutting allowance at the sharp-angled part, the tool is subjected to strong impact during processing and often breaks during processing the sharp-angled part, causing the tool fragments to pierce the locking groove; at the same time, due to the tool letting go during processing, there is a slight verticality difference between the groove mouth and the groove bottom. Summary of the invention

[0004] The present invention aims to solve the problems of locking groove puncture and poor verticality of the locking groove caused by easy breakage of the tool when machining the sharp angle in the existing method for machining the locking groove of the last blade, and further provides a new method for machining the locking groove of the last blade by a planing and slotting machine to solve the problems raised in the above background technology.

[0005] The technical solution of the present invention is:

[0006] A novel method for machining a locking groove of a last blade by a planing and slotting machine, the method comprising the following steps:

[0007] Step 1: Draw a CAD drawing of the diamond-shaped quadrilateral of the lock to be processed, including the workpieces to be processed and the feed space at the left and right ends of the lock, wherein the workpiece to be processed is divided into an acute-angle triangle part, a rectangular part and an obtuse-angle triangle part;

[0008] Step 2: Select a tool, and select a rough insert tool;

[0009] Step 3: Rough machining the rectangular part of the workpiece to be machined in the lock diamond quadrilateral. The rough inserting tool enters from the feed space. The tool cutting starting point is the acute angle side of the feed space. The rough inserting tool reciprocates and machines according to a serpentine trajectory. Finally, the machining ends at a 0.1mm margin left at the rectangle of the straight edge workpiece, and the tool withdraws from workpiece 4.

[0010] Step 4: Replace the tool and select the fine insert tool;

[0011] Step 5: Semi-finishing the acute triangle part of the workpiece to be processed in the lock diamond quadrilateral. The fine inserting tool piece enters from the feed space and uses the tool acute angle piece for cutting. During processing, the tool acute angle piece is parallel to the two sides of the lock diamond quadrilateral acute angle piece, and the tool is moved from right to upper left. Each cut is 0.05mm. Finally, a 0.5mm margin is left on the upper bevel, and a 0.2mm margin is left on the right-angled side of the upper triangle of the straight side. The tool withdraws from the feed space;

[0012] Step 6: Semi-finishing the obtuse triangle part of the workpiece to be processed in the lock diamond quadrilateral. The fine inserting tool enters from the feed space and uses the tool obtuse part for cutting. During processing, the tool obtuse part is parallel to the two sides of the obtuse part of the lock diamond quadrilateral, and the tool is moved from right to upper left. Each cut is 0.05mm. Finally, a 0.5mm margin is left on the lower bevel, and a 0.1mm margin is left at the acute angle vertex of the triangle at the lower end of the straight side. The tool withdraws from the feed space;

[0013] Step 7: Finish machining the allowance at the acute angle of the workpiece to be machined. The fine inserting tool piece enters from the feed space and uses the tool acute angle piece for cutting. During machining, the sharp angle side cutting edge of the fine inserting tool piece coincides with the upper bevel. The fine inserting tool piece processes along the upper bevel toward the vertex of the acute angle piece. Each cut is 0.2mm. The machining is completed when the distance between the straight edge of the fine inserting tool piece and the straight edge of the lock diamond quadrilateral is 0.1mm, and the tool is withdrawn.

[0014] Step 8, fine machining the allowance at the obtuse angle of the workpiece to be machined, the fine inserting tool piece enters from the feed space, and the tool obtuse angle piece is used for cutting. During machining, the cutting edge of the obtuse angle side of the fine inserting tool piece coincides with the lower bevel, and the fine inserting tool piece is machined along the lower bevel toward the vertex of the obtuse angle piece, and each cut is 0.2mm, until the tool obtuse angle piece coincides with the obtuse angle piece of the lock mouth rhombus quadrilateral, and the straight edge of the fine inserting tool piece coincides with the straight edge of the lock mouth rhombus quadrilateral;

[0015] Then the fine inserting tool piece moves along the straight edge from bottom to top, cutting 0.2mm per cut, until the acute angle piece of the tool overlaps with the acute angle piece of the four sides of the lock rhombus, and then the fine inserting tool piece moves along the straight edge from top to bottom again, cutting until the blunt angle piece of the tool overlaps with the blunt angle piece of the four sides of the lock rhombus; finally, the fine inserting tool piece moves along the straight edge from bottom to top again, cutting 0.2mm per cut, until the blunt angle piece of the tool overlaps with the blunt angle piece of the four sides of the lock rhombus, completing three reciprocating turnings;

[0016] Step 9. According to the methods of steps 2 to 8, process the workpiece area on the symmetrical side of the four sides of the lock diamond to complete the processing of the entire four sides of the lock diamond.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] A new method for machining the locking groove of the last blade by using a planing and slotting machine. The locking groove of the last blade of a turbine rotor is machined by using a planing and slotting machine. The machining of the locking groove is divided into rough machining, semi-finishing, and finishing after leaving a small amount of allowance. The rectangular part of the workpiece to be machined is machined by a rough slotting tool, and then the acute triangle part and the obtuse triangle part of the workpiece to be machined are machined by a fine slotting tool. Finally, the allowance part is machined by a fine slotting tool. The feed amount when using the fine slotting tool is reduced, and the cutting resistance of the tool during finishing is greatly reduced. In this way, the occurrence of the tool hitting the sharp corner of the locking diamond quadrilateral is avoided to prevent the fine slotting tool from breaking. Through rough machining, semi-finishing and finishing, the machining allowance is reduced in sequence, which not only ensures the machining efficiency, but also prevents the possibility of tool breakage when machining sharp angles.

[0019] In the existing processing technology, the straight edge of the lock rhombus quadrilateral is processed once. During processing, the tool is subjected to the cutting resistance, and there is a tool yield when processing from the slot mouth to the bottom of the slot. The bottom processing size is inaccurate, resulting in the processing surface piece 9 not being perpendicular to the bottom surface. The technology of the present invention adopts a reciprocating three-time processing method for the straight edge of the lock slot rhombus quadrilateral. This processing method can accurately correct the tool yield part of the processing surface, ensure that the verticality of the straight edge and the bottom of the lock slot after processing is controlled within 0.02, and meet the requirements of the lock slot design drawing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the lock rhombus quadrilateral of the present invention;

[0021] Figure 2 It is a schematic diagram of the rough processing of the lock rhombus quadrilateral of the present invention;

[0022] Figure 3 It is a schematic diagram of the semi-finishing of the acute angle of the rhombus quadrilateral of the lock mouth of the present invention;

[0023] Figure 4 yes Figure 3 A partial enlarged view of

[0024] Figure 5 It is a schematic diagram of the semi-finishing of the obtuse angle of the lock rhombus quadrilateral of the present invention;

[0025] Figure 6 yes Figure 5 A partial enlarged view of

[0026] Figure 7 This is a schematic diagram of the rough insert structure of the present invention;

[0027] Figure 8 This is a schematic diagram of the structure of the precision inserting knife of the present invention;

[0028] Fig. 9 It is a schematic diagram of the precision processing of the lock rhombus quadrilateral of the present invention.

[0029] In the figure: 1, acute-angled part; 2, obtuse-angled part; 3, part to be processed; 4, feed space; 5, rough insert part; 6, fine insert part; 7, tool acute-angled part; 8, tool obtuse-angled part; 9, straight-edge part; 10, beveled part; 11, upper triangular part I; 12, upper triangular part II; 13, upper triangular part III; 14, beveled part; 15, lower triangular part I; 16, lower triangular part II; 17, lower triangular part III; H1, width to be processed; H2, feed space width; H3, rough insert cutting width; H4, rough insert overall width; H5, fine insert cutting width; H6, fine insert overall width; H7, rough machining cutting depth; H9, machining width; H10, semi-finishing area width; H11, fine insert width; D1, bevel allowance; D2, straight edge allowance. DETAILED DESCRIPTION

[0030] Specific implementation method 1: See Figure 1-9 As shown, a novel planing and slotting machine method for processing the locking groove of the last blade, this embodiment has the following steps:

[0031] Step 1: Draw a CAD drawing of a diamond-shaped quadrilateral of the lock to be processed, including the workpiece 3 to be processed and the feed space 4 at the left and right ends of the lock, wherein the workpiece 3 to be processed is divided into an acute triangle part, a rectangular part and an obtuse triangle part;

[0032] Step 2: Clamp the workpiece and select a tool, which is a rough inserting tool 5;

[0033] Step 3: Rough machining of the rectangular part of the workpiece 3 to be machined in the lock diamond quadrilateral. The rough inserting tool 5 enters from the feed space 4. The tool cutting starting point is the acute angle side of the feed space 4. The rough inserting tool 5 performs machining by reciprocating the cutter in a serpentine trajectory. The machining ends at a point where a 0.1mm margin is left at the rectangle of the straight edge workpiece 9. The tool withdraws from the workpiece 4.

[0034] Step 4: Replace the tool and select the fine insert tool 6;

[0035] Step 5, semi-finishing the acute triangle part of the workpiece 3 to be processed in the lock diamond quadrilateral, the fine inserting tool 6 enters from the feed space 4, and the tool acute angle part 7 is used for cutting. During processing, the tool acute angle part 7 is parallel to the two sides of the lock diamond quadrilateral acute angle part 1, and the tool is moved from right to upper left, with each cut cutting 0.05mm, and finally the upper bevel 10 is processed with a 0.5mm margin, and the upper end of the straight side 9 The triangle right angle side has a 0.2mm margin, and the tool withdraws from the feed space 4;

[0036] Step 6, semi-finishing the obtuse triangle part of the workpiece 3 to be processed in the lock rhombus quadrilateral, the fine inserting tool 6 enters from the feed space 4, and the tool obtuse angle part 8 is used for cutting. During processing, the tool obtuse angle part 8 is parallel to the two sides of the obtuse angle part 2 of the lock rhombus quadrilateral, and the tool is moved from right to upper left, with each cut cutting 0.05mm, and processing to the lower bevel 14 leaving a 0.5mm margin, and leaving a 0.1mm margin at the acute angle vertex of the triangle at the lower end of the straight edge 9. Then the fine inserting tool 6 and the straight edge 9 keep 0.1mm and start processing from bottom to top, and each cut cutting 0.2mm until the acute angle side is 0.5mm away from the upper bevel 10 of the lock rhombus, and the straight edge 9 leaves a 0.1mm margin, and the tool withdraws from the feed space 4;

[0037] Step 7, fine machining the allowance at the acute angle of the workpiece 3, the fine inserting tool 6 enters from the feed space 4, and uses the tool acute angle piece 7 to cut. During machining, the sharp angle side cutting edge of the fine inserting tool 6 coincides with the upper bevel 10, and the fine inserting tool 6 is machined along the upper bevel 10 toward the vertex of the acute angle piece 1, with each cut cutting 0.2mm, and the machining is completed when the distance between the straight edge of the fine inserting tool 6 and the straight edge 9 of the locking diamond quadrilateral is 0.1mm, and the tool is withdrawn;

[0038] Step 8, fine machining the allowance at the obtuse angle of the workpiece 3 to be machined, the fine inserting tool 6 enters from the feed space 4, and the tool obtuse angle part 8 is used for cutting. During machining, the obtuse angle side cutting edge of the fine inserting tool 6 coincides with the lower bevel 14, and the fine inserting tool 6 is machined along the lower bevel 14 toward the vertex direction of the obtuse angle part 2, and each cut is cut by 0.2mm, until the tool obtuse angle part 8 coincides with the locking rhombus quadrilateral obtuse angle part 2, and the straight edge of the fine inserting tool 6 coincides with the straight edge 9 of the locking rhombus quadrilateral;

[0039] Then, the fine inserting tool 6 moves along the straight edge 9 from bottom to top, cutting 0.2mm per cut, until the tool acute angle piece 7 overlaps with the lock-mouth rhombus quadrilateral acute angle piece 1, and the fine inserting tool 6 moves along the straight edge 9 from top to bottom again, cutting until the tool blunt angle piece 8 overlaps with the lock-mouth rhombus quadrilateral blunt angle piece 2; finally, the fine inserting tool 6 moves along the straight edge 9 from bottom to top again, cutting 0.2mm per cut, until the tool blunt angle piece 7 overlaps with the lock-mouth rhombus quadrilateral acute angle piece 1, completing three reciprocating turnings;

[0040] Step 9. According to the methods of steps 2 to 8, process the area of ​​the workpiece 3 on the symmetrical side of the four sides of the lock diamond, and complete the processing of the entire four sides of the lock diamond.

[0041] Further, first draw the CAD drawing of the lock rhombus quadrilateral to be processed, design and process the precision inserting tool 6 with the same obtuse angle and acute angle as the lock rhombus quadrilateral. Execute to complete step three, according to Figure 2Move the tool in the direction of the arrow of the middle serpentine path. After completing the processing of the rectangular part of the workpiece 3 to be processed, the remaining parts to be processed are: 0.1mm allowance of the upper acute triangle part, the lower obtuse triangle part and the straight edge part 9. Execute to complete step 5. After completing the semi-finishing of the acute triangle part of the workpiece 3 to be processed, the remaining parts to be processed are: 0.2mm allowance of the upper acute triangle straight edge part, 0.5mm allowance of the upper bevel 10, 0.1mm allowance of the lower obtuse triangle part and the straight edge part 9. Execute to complete step 6. After completing the semi-finishing of the obtuse triangle part of the workpiece 3 to be processed, the remaining parts to be processed are: 0.5mm allowance of the upper bevel 10, 0.5mm allowance of the lower bevel 14 and 0.1mm allowance of the straight edge part 9. Execute to complete step 7. Complete the finishing of the allowance of the acute angle of the workpiece 3 to be processed. The remaining parts to be processed are: 0.5mm allowance of the lower bevel 14 and 0.1mm allowance of the straight edge part 9. Execute to step eight to complete the processing of all remaining allowances.

[0042] Furthermore, the rectangular part of the workpiece to be processed is processed with a rough insert, and the acute triangle part and the obtuse triangle part of the workpiece to be processed are processed with a fine insert, and finally the remaining part is processed with a fine insert. The feed amount when using the fine insert is reduced, and the cutting resistance of the tool during fine processing is greatly reduced. This avoids the occurrence of tool breakage at the sharp corners of the lock rhombus quadrilateral, so as to prevent the fine insert from breaking. Through rough processing, semi-finishing and fine processing, the processing allowance is reduced in turn, and the processing efficiency is maximized.

[0043] Furthermore, in step eight, the last 1mm margin of the straight edge pieces 9 on the four sides of the diamond-shaped lock groove is processed by reciprocating three times. This processing method can accurately correct the tool-allowing part of the processing surface and ensure that the verticality of the straight edge and the bottom of the lock groove after processing is controlled within 0.02, meeting the requirements of the lock groove design drawings.

[0044] Specific implementation method 2: See Figure 3-4 As shown, the specific steps of cutting the acute triangle part in step 5 are as follows:

[0045] Step 51: Calculate the processing width H9 of the upper triangle area;

[0046] Step 52: Divide the upper triangle area processing width H9 into N layers for processing according to the fine inserting tool width H11, N = H9 ÷ (H11 / 2). If the calculation result shows that the processing width of the last layer is less than 1mm, it can be merged into the previous layer for processing;

[0047] Step 53: If N=3, the upper triangle is divided into three parts: upper triangle part Ⅰ11, upper triangle part Ⅱ12, and upper triangle part Ⅲ13. The tool enters from the tool feed space 4 and processes the upper triangle part Ⅰ11, upper triangle part Ⅱ12, and upper triangle part Ⅲ13 in sequence;

[0048] Step 54: The fine inserting tool 6 enters from the feed space 4 and is cut using the tool acute angle piece 7. During processing, the tool acute angle piece 7 is parallel to the two sides of the lock diamond quadrilateral acute angle piece 1, and the tool is moved from right to upper left, with each cut cutting 0.05mm. Finally, a 0.5mm margin is left on the upper bevel 10, and a 0.2mm margin is left on the upper triangular right-angled side of the straight edge 9. The tool withdraws from the feed space 4.

[0049] Specific implementation method three: see Figure 5-6 As shown, the specific steps of cutting the obtuse triangle part in step six are as follows:

[0050] Step 61: Calculate the processing width H10 of the lower triangle area;

[0051] Step 62: Divide the lower triangle area processing width H10 into N layers for processing according to the fine inserting tool width H11, N = H9 ÷ (H110 / 2). If the calculation result shows that the processing width of the last layer is less than 1mm, it can be merged into the previous layer for processing;

[0052] Step 63: If N=3, the lower triangle is divided into three parts: lower triangle part Ⅰ15, lower triangle part Ⅱ16, and lower triangle part Ⅲ17. The tool enters from the tool feed space 4 and processes the lower triangle part Ⅰ15, lower triangle part Ⅱ16, and lower triangle part Ⅲ17 in sequence;

[0053] Step 64: The fine inserting tool 6 enters from the feed space 4 and is cut using the tool obtuse-angled part 8. During processing, the tool obtuse-angled part 8 is parallel to the two sides of the locking rhombus quadrilateral obtuse-angled part 2, and the tool is moved from right to upper left, with each cut cutting 0.05mm. Finally, a 0.5mm margin is left on the lower bevel 14, and a 0.1mm margin is left at the acute angle vertex of the triangle at the lower end of the straight edge 9. The tool exits from the feed space 4.

[0054] Furthermore, the above embodiment specifically describes the semi-finishing processing method of the acute triangle part and the obtuse triangle part. In the two processings, the tool acute angle piece 7 is parallel to the two sides of the locking diamond quadrilateral acute angle piece 1 and the tool obtuse angle piece 8 is parallel to the two sides of the locking diamond quadrilateral obtuse angle piece 2. When the tool moves to the processing end point, the acute angle piece 1 and the obtuse angle piece 2 of the workpiece 3 to be processed respectively form the same angle as the tool acute angle piece 7 and the tool obtuse angle piece 8 of the fine inserting tool piece 6, thereby determining the angle of the locking groove when the processing is completed.

[0055] Specific implementation method four: see Figure 2 As shown, in step three of the present embodiment, when rough machining the rectangular part of the workpiece 3 in the locking diamond quadrilateral, the rough machining cutting depth H7 in the positive direction of the Z axis is 0.2 mm each time, and the tool is first cut downward in the X axis direction, and the cutting width of each tool is 0.05 mm.

[0056] Specific implementation method five: see Figure 2 As shown, in step 2 of this embodiment, the rough inserting tool 5 is selected from: a blade whose width to be processed H1 is smaller than the cutting width H3 of the rough inserting tool, and whose overall width H4 of the rough inserting tool is smaller than the width H2 of the feed space.

[0057] Specific implementation method six: see Figure 2 As shown, in step 4 of this embodiment, the fine inserting tool 6 is selected from: a blade whose processing width H1 is smaller than the fine inserting tool cutting width H5, and whose overall width H6 of the fine inserting tool is smaller than the feed space width H2 of the feed space 4.

[0058] Specific implementation method seven: See Figure 2 As shown, the precision inserting tool piece 6 of this embodiment uses: the tool acute angle piece 7 is the same as the locking rhombus quadrilateral acute angle piece 1, and the tool obtuse angle piece 8 is the same as the locking rhombus quadrilateral obtuse angle piece 2.

[0059] Furthermore, the rough inserting tool 5 is selected: the rough inserting tool cutting width H3 is greater than the width to be processed H1, so as to ensure that there is sufficient processing depth so that the width to be processed H1 can be fully processed. The rough inserting tool has a blade whose overall width H4 is less than the width H2 of the feed space, so that there is enough space when feeding, preventing the tool from not being able to penetrate into the feed space 4. The selection of the above-mentioned fine inserting tool 6 is similar. The fine inserting tool 6 is selected: the tool acute angle piece 7 is the same as the sharp angle piece 1 of the four sides of the lock rhombus, and the tool obtuse angle piece 8 is the same as the obtuse angle piece 2 of the four sides of the lock rhombus, so that after the processing is completed, the four corners of the lock slot rhombus form the same angles as the tool acute angle piece 7 and the tool obtuse angle piece 8 of the fine inserting tool 6.

[0060] Specific implementation method eight: See Figure 2 As shown, the method of this embodiment adopts a vertical planing machine for processing.

[0061] Specific implementation method nine: See Figure 2 As shown, the blade material of the rough inserting tool 5 and the fine inserting tool 6 in this embodiment is M42, and the tool body material is 45# steel.

[0062] Specific implementation method ten: See Figure 2 As shown, the specific part of clamping the workpiece in step 1 in this embodiment is as follows:

[0063] Step 1: Insert the two ends of the shaft into the support fixture respectively;

[0064] Step 1 and 2: Use fasteners to tighten the shaft diameter in the support fixture from top to bottom;

[0065] Step 1 and 3: Install protective sleeves on both ends of the shaft diameter, and the workpiece clamping is completed.

Claims

1. A novel method for machining the locking groove of the last blade by a planing and slotting machine, characterized in that: The method comprises the following steps: Step 1: Draw the CAD drawing of the diamond-shaped quadrilateral of the lock to be processed. It includes a workpiece (3) to be processed at the left and right ends of the lock and a tool feed space (4), wherein the workpiece (3) to be processed is divided into an acute-angled triangle part, a rectangular part and an obtuse-angled triangle part; Step 2: Clamp the workpiece, select a tool, and select a rough insert tool (5); Step 3: Rough machining of the rectangular portion of the workpiece (3) to be machined in the lock diamond quadrilateral. The rough inserting tool (5) enters from the feed space (4). The tool cutting starting point is the acute angle side of the feed space (4). The rough inserting tool (5) performs machining by reciprocating the cutter in a serpentine trajectory. The machining is finally completed at a position where a 0.1 mm margin is left at the rectangular portion of the straight edge workpiece (9). The tool is then withdrawn from workpiece 4. Step 4: Replace the tool and select the fine insert tool (6); Step 5: semi-finishing the acute triangle part of the workpiece (3) to be processed in the lock-mouth rhombus quadrilateral. The fine inserting tool (6) enters from the feed space (4) and uses the tool acute angle part (7) to cut. During processing, the tool acute angle part (7) is parallel to the two sides of the lock-mouth rhombus quadrilateral acute angle part (1). The tool is moved from right to upper left, and each cut is 0.05 mm. Finally, a 0.5 mm margin is left on the upper bevel (10), and a 0.2 mm margin is left on the upper end of the straight side (9). The tool is withdrawn from the feed space (4); Step 6: semi-finishing the obtuse triangle part of the workpiece (3) to be processed in the lock-mouth rhombus quadrilateral. The fine inserting tool (6) enters from the feed space (4) and uses the tool obtuse angle part (8) to cut. During processing, the tool obtuse angle part (8) is parallel to the two sides of the obtuse angle part (2) of the lock-mouth rhombus quadrilateral, and the tool moves from right to upper left. Each cut cuts 0.05mm until the lower bevel (14) has a 0.5mm margin, and the triangle acute angle vertex at the lower end of the straight edge (9) has a 0.1mm margin. Then, the fine inserting tool (6) and the straight edge (9) keep 0.1mm from bottom to top, and each cut cuts 0.2mm until the acute angle side has a 0.5mm distance from the upper bevel (10) of the lock-mouth rhombus, and the straight edge (9) has a 0.1mm margin. The tool withdraws from the feed space (4); Step 7, fine machining the allowance at the acute angle of the workpiece (3), the fine inserting tool (6) enters from the feed space (4), and uses the tool acute angle piece (7) to cut. During machining, the sharp angle side cutting edge of the fine inserting tool (6) coincides with the upper bevel (10), and the fine inserting tool (6) is machined along the upper bevel (10) toward the vertex of the acute angle piece (1), with each cut cutting 0.2mm. The machining is completed when the distance between the straight edge of the fine inserting tool (6) and the straight edge (9) of the locking diamond quadrilateral is 0.1mm, and the tool is withdrawn; Step 8, finishing the allowance at the obtuse angle of the workpiece (3), the fine inserting tool (6) enters from the feed space (4), and uses the tool obtuse angle piece (8) to cut, during which the obtuse angle side cutting edge of the fine inserting tool (6) coincides with the lower bevel (14), and the fine inserting tool (6) processes along the lower bevel (14) toward the vertex of the obtuse angle piece (2), with each cut cutting 0.2 mm, until the tool obtuse angle piece (8) coincides with the locking diamond quadrilateral obtuse angle piece (2), and the straight edge of the fine inserting tool (6) coincides with the straight edge (9) of the locking diamond quadrilateral; Then, the fine inserting tool (6) moves along the straight edge (9) from bottom to top, cutting 0.2 mm per cut, until the tool acute angle piece (7) overlaps with the lock-mouth rhombus four-sided acute angle piece (1), and the fine inserting tool (6) moves along the straight edge (9) from top to bottom again, cutting until the tool blunt angle piece (8) overlaps with the lock-mouth rhombus four-sided blunt angle piece (2); finally, the fine inserting tool (6) moves along the straight edge (9) from bottom to top again, cutting 0.2 mm per cut, until the tool acute angle piece (7) overlaps with the lock-mouth rhombus four-sided acute angle piece (1), completing three reciprocating turnings; Step 9, according to the methods of steps 2 to 8, process the area of ​​the workpiece (3) on the symmetrical side of the four sides of the lock diamond, and complete the processing of the entire four sides of the lock diamond.

2. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1 is characterized in that: The specific steps of cutting the acute triangle part in step 5 are as follows: Step 51: Calculate the processing width of the upper triangle area (H9); Step 52: Divide the upper triangle area processing width (H9) into N layers for processing according to the fine insert width (H11), N = H9 ÷ (H11 / 2). If the calculation result shows that the processing width of the last layer is less than 1mm, it can be merged into the previous layer for processing; Step 53: If N=3, the upper triangle is divided into three parts: upper triangle part I (11), upper triangle part II (12), and upper triangle part III (13). The tool enters from the tool feed space (4) and processes the upper triangle part I (11), upper triangle part II (12), and upper triangle part III (13) in sequence; Step 54: The fine inserting tool (6) enters from the tool feed space (4) and is cut using the tool acute angle piece (7). During processing, the tool acute angle piece (7) is parallel to the two sides of the lock rhombus quadrilateral acute angle piece (1), and the tool is moved from right to upper left, with each cut cutting 0.05mm until the upper bevel (10) is processed with a 0.5mm margin, and a 0.1mm margin is left at the upper end of the straight edge (9) The right angle of the triangle, the tool is withdrawn from the tool feed space (4).

3. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1, characterized in that: The specific steps of cutting the obtuse triangle part in step 6 are as follows: Step 61: Calculate the processing width of the lower triangle area (H10); Step 62: Divide the lower triangle area processing width (H10) into N layers for processing according to the fine insert width (H11), N = H9 ÷ (H110 / 2). If the calculation result shows that the processing width of the last layer is less than 1mm, it can be merged into the previous layer for processing; Step 63: If N=3, the lower triangle is divided into three parts: lower triangle part I (15), lower triangle part II (16), and lower triangle part III (17). The tool enters from the tool feed space (4) and processes the lower triangle part I (15), lower triangle part II (16), and lower triangle part III (17) in sequence; Step 64: The fine inserting tool (6) enters from the feed space (4) and is cut using the tool blunt angle piece (8). During processing, the tool blunt angle piece (8) is parallel to the two sides of the lock rhombus quadrilateral blunt angle piece (2), and the tool is moved from right to upper left, with each cut cutting 0.05mm. Finally, a 0.5mm margin is left at the lower bevel (14), and a 0.1mm margin is left at the acute angle vertex of the triangle at the lower end of the straight edge (9). The tool is then withdrawn from the feed space (4).

4. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1 is characterized in that: Step 3: When rough machining the rectangular part of the workpiece (3) in the locking diamond quadrilateral, the rough machining cutting depth (H7) in the positive direction of the Z axis is 0.2 mm each time, and the tool is cut downward in the X axis direction first, and the cutting width of each tool is 0.05 mm.

5. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1 is characterized in that: In step 2, the rough inserting tool (5) is selected from blades whose width to be processed (H1) is smaller than the cutting width (H3) of the rough inserting tool and whose overall width (H4) of the rough inserting tool is smaller than the width of the feed space (H2).

6. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1 is characterized in that: In step 4, the fine inserting tool (6) is selected from blades whose width to be processed (H1) is smaller than the cutting width (H5) of the fine inserting tool, and whose overall width (H6) of the fine inserting tool is smaller than the feed space width (H2) of the feed space (4).

7. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 6 is characterized in that: The precision inserting tool piece (6) is selected from the following blades: the acute angle piece (7) of the tool is the same as the acute angle piece (1) of the locking rhombus quadrilateral, and the blunt angle piece (8) of the tool is the same as the blunt angle piece (2) of the locking rhombus quadrilateral.

8. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1 is characterized in that: The method adopts a vertical planing machine for processing.

9. The method for machining the locking groove of the last blade by a new type of planing and slotting machine according to claim 1 is characterized in that: The blade material of the rough inserting knife piece (5) and the fine inserting knife piece (6) is M42, and the knife body material is 45# steel.

10. The novel planing and slotting machine method for processing the locking groove of the last blade according to claim 1, characterized in that: The specific parts of clamping the workpiece in step 1 are as follows: Step 1: Insert the two ends of the shaft into the support fixture respectively; Step 1 and 2: Use fasteners to tighten the shaft diameter in the support fixture from top to bottom; Step 1 and 3: Install protective sleeves on both ends of the shaft diameter, and the workpiece clamping is completed.

Images