A Measuring Method for the Clamping Phase Error of a Triangular Indexable Insert

Abstract

The present invention relates to a method for measuring the clamping phase error of a triangular indexable insert, belonging to the technical field of machine tool blade processing. In this method, the blank of the triangular indexable insert is clamped on the workpiece fixture of a peripheral grinding numerical control machine tool. According to the actual geometric features of the processed triangular indexable insert blank and its position on the machine tool, a triangle A0B0C without eccentric error clamping is obtained 0、 The included angle between the centerlines of the actually clamped triangle ABC is the phase error. This method can be input into the machine tool to measure and eliminate the phase error generated by clamping the blade. This method has the characteristics of high efficiency, high accuracy, and wide applicability

Description

Technical Field

[0001] The present invention relates to a method for measuring the clamping phase error of a triangular indexable insert, belonging to the technical field of machine tool insert processing. Background Art

[0002] In the grinding production of indexable inserts, auxiliary tooling is usually used to control the longitudinal axis phase error when clamping and loading the polygonal indexable insert blank. In actual clamping, the geometric center of the tool and the phase origin of the machine tool spindle do not coincide, forming a phase error, resulting in incomplete machining of the part and incorrect dimensions. However, the eccentricity of the tool cannot be directly measured by tools, and only the position of the auxiliary tooling bracket can be repeatedly tested during machining to reduce the phase error of the insert. This method leads to low processing efficiency and takes a long time to calculate the phase error of the tool by reverse calculation based on the dimensional deviation of the part. Especially in the process of small-batch flexible production, that is, the production of multiple types of small-batch inserts, it is often necessary to frequently replace and adjust the insert bracket to ensure the phase error of the insert. For some special-shaped inserts with holes, it is time-consuming and laborious to use the bracket for phase adjustment. There are problems such as low efficiency and unreliable adjustment. In order to ensure the accuracy of the finished product, it is urgent to measure the phase error of the insert. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to propose a method for measuring the clamping phase error of a triangular indexable insert in view of the deficiencies of the prior art. The method is characterized in that: the triangular indexable insert blank is clamped on the workpiece fixture of a peripheral grinding numerical control machine tool, and according to the processed triangular indexable insert blank and its actual geometric features on the machine tool, the included angle between the center lines of the triangle A0B0C0 clamped in the ideal state without eccentricity error and phase error and the center line of the actually clamped triangle ABC is calculated, which is the phase error , to ensure the accuracy of the finished product.

[0004] To solve the above technical problem, the present invention proposes a method for measuring the clamping phase error of a triangular indexable insert. As Figure 2 shown, the triangular indexable insert blank is clamped on the workpiece fixture of a peripheral grinding numerical control machine tool. According to the processed triangular indexable insert blank and its actual geometric features on the machine tool, as Figure 3 shown, the included angle between the center lines of the triangle A0B0C0 clamped in the ideal state without eccentricity error and phase error and the center line of the actually clamped triangle ABC is obtained, which is the phase error ; As Figure 4 shown, the specific measurement method steps include:

[0005] 1.1 Determine the distance d from the sensor to the rotation center of the B-axis of the machine tool and the inscribed circle diameter of the measured blank in advance .

[0006] 1.2 The sensor probe measures and records the distance to AC as .

[0007] 1.3 Let the angle between the line passing through the origin O and perpendicular to side AC and the X-axis be α degrees, and rotate the B-axis clockwise degrees , and construct the triangle A1B1C1 after the rotation of the B-axis .

[0008] 1.4 The sensor probe measures and records the distance to A1C1 as .

[0009] 1.5 Calculate the initial phase α of the blade clamping;

[0010] The distances from each side to the rotation center of the machine tool B-axis are: , record the size (height width) of the sensor probe as H W mm, and record half of the height H . From the geometric relationship, it can be obtained that ,

[0011] This equation is a transcendental equation without an analytical solution, so the bisection interval method is used to calculate its numerical solution;

[0012] (1) Establish the equation .

[0013] (2) is the angle under the ideal error-free condition. For the triangular blade, it is 30°. Considering the error range of ±0~10° and the error margin of 5°, it can be obtained that has a real root within .

[0014] (3) Let the tolerance be 1*10-4.

[0015] (4) Iterative solution: Let

[0016] The continuous function has only one real root within , and satisfies ;

[0017] a. Record , and take the midpoint of the interval ;

[0018] b. Judge the value of . If , then output , and stop; if , record , otherwise record ;

[0019] c. Record , then take ;

[0020] d. If , then output , stop; otherwise replace go to step (1).

[0021] 1.5 According to the above calculation, the phase error of the blade clamping , .

[0022] Input this method into the machine tool, and it can measure and eliminate the phase error generated by clamping the blade. Thus, the machining accuracy of the blade is improved. After experimental measurement, the experimental results show that after eliminating the phase error by using this method, the deviation is within ±4 . This method has the characteristics of high efficiency, high accuracy, wide applicability, etc. Brief Description of the Drawings

[0023] Figure 1 is a schematic diagram of the structures of each axis of the four-axis numerically controlled peripheral grinder of the present invention.

[0024] Figure 2 is a schematic diagram of the blade clamping body structure of the present invention.

[0025] Figure 3 is a schematic diagram of the ideal non-eccentric error state and the actual clamping of the triangular indexable blade of the present invention.

[0026] Figure 4 is a schematic diagram of the phase error measurement of the triangular indexable blade of the present invention.

[0027] Figure 5 is a schematic diagram of the phase error measurement example of the triangular indexable blade of the present invention. Detailed Description of the Preferred Embodiments

[0028] The following further describes in detail the specific embodiments of the present invention. Technologies or products not specified in the embodiments are all existing technologies or conventional products that can be obtained by purchase.

[0029] Embodiment 1: As Figure 5 shown, for this method of measuring the phase error of clamping the triangular indexable blade, this method requires using a square measuring probe. The size of the probe in this example is 40x25 mm. Record half of the height Clamp the triangular indexable insert blank on the workpiece fixture of the peripheral grinding CNC machine tool. According to the triangular indexable insert blank to be machined and its actual geometric features on the machine tool, calculate the included angle between the center line of triangle A0B0C0 clamped without eccentricity error and phase error in the ideal state and the center line of the actually clamped triangle ABC, which is the phase error. The specific measurement method steps include:

[0030] 1.1 Determine the distance from the sensor to the rotation center of the B-axis of the machine tool , and measure the diameter of the inscribed circle of the blank .

[0031] 1.2 The sensor measures and records the distance to AC as .

[0032] 1.3 Let the included angle between the straight line perpendicular to side AB at the origin O and the X-axis be α degrees, rotate the B-axis clockwise by 8 degrees, and construct triangle A1B1C1 after the rotation of the B-axis .

[0033] 1.4 The sensor probe measures and records the distance to A1C1 as .

[0034] 1.5 Calculate the initial phase α of the insert clamping;

[0035] The distances from each side to the rotation center of the B-axis of the machine tool are: ,

[0036] From the geometric relationship, it can be obtained that ,

[0037] This equation has no analytical solution, so the bisection interval method is used to calculate its numerical solution;

[0038] (5)Establish the equation .

[0039] (6) is the angle under the ideal error-free condition. For a triangular insert, it is 30°. Considering the error range of ±0~10° and the error margin of 5°, it can be obtained that There is a real root in .

[0040] (7)Set the tolerance as 1*10-4.

[0041] (8)Iterative solution: Let

[0042] The continuous function in has only one real root and satisfies ;

[0043] a. Denote , and take the midpoint of the interval ;

[0044] b. Determine the value of . If , then output , and stop; if , denote , otherwise denote:

[0045] ;

[0046] c. Denote , and then take ;

[0047] d. If , then output , and stop; otherwise replace and go back to step (1).

[0048] The calculation gives . Substituting it into yields:

[0049]

[0050] , and the calculation result holds.

[0051] 1.5 According to the above calculation of the blade clamping phase error , , the measured calculation error is 0.0327° = 1.962 .

[0052] The above has described the technical content of the present invention, but the protection scope of the present invention is not limited to the described content. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made to the technical content of the present invention without departing from the purpose of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for measuring the phase error of a triangular indexable insert during clamping, characterized in that: The triangular indexable insert blank is clamped on the peripheral grinding CNC machine tool workpiece fixture. According to the processed triangular indexable insert blank and its actual geometric characteristics on the machine tool, the angle between the center line of the ideal clamped triangle A0B0C0 without eccentricity error and phase error and the center line of the actual clamped triangle ABC is obtained, which is the phase error. ; The specific measurement method steps include: 1.1 Clamp the triangular indexable insert blank on the peripheral grinding CNC machine tool workpiece fixture; 1.2 According to the actual geometric characteristics of the clamped blank, construct the triangle A0B0C0 corresponding to the ideal clamping state and the triangle ABC corresponding to the actual clamping state; 1.3 Before measuring, determine the distance d from the sensor to the center of rotation of the machine tool B axis and measure the diameter of the inscribed circle of the blank. ; 1.4 The sensor probe measures and records the distance to AC. ; 1.5 Let the angle between the straight line passing through the origin O and perpendicular to the side AC and the X-axis be α degrees, and rotate the B axis clockwise Spend , and construct the B-axis rotation The triangle after that is A1B1C1; 1.6 The sensor probe measures and records the distance to A1C1. ; 1.7 Calculate the initial phase α of the insert clamping; The distance from each side to the center of rotation of the machine tool B axis is: , record the sensor probe height as Hmm, record half of the height H ; From the geometric relationship, we can get ,This equation is a transcendental equation and has no analytical solution, so the bisection interval method is used to calculate its numerical solution; (1) Establish the equation ; (2) Under ideal error-free conditions Angle, for triangular blades, is 30°, from the error within ±0~10°, 30°±10° and considering the error margin of 5°, we can get exist There is one real root; (3) Assume the tolerance is 1*10-4; (4) Iterative solution: Let , Continuous Function exist There is only one real root and it satisfies ; a. Remember , take the midpoint of the interval ; b. Discrimination If the value of , then the output , stop; if ,remember , otherwise remember ; c. Remember , then take ; d. If , then the output , stop; otherwise replace Go to step (1); 1.8 Calculate the blade clamping phase error based on the above , Since the blade is an equilateral triangle, .

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