An eccentric error method for machining regular polygon indexable inserts

Abstract

The present invention relates to a method for processing the eccentric error of a rotatable indexable insert with a regular polygon, belonging to the technical field of machine tool insert processing. The blank of the rotatable indexable insert with a regular polygon is clamped on the workpiece fixture of a peripheral grinding numerical control machine tool. According to the blank of the rotatable indexable insert with a regular polygon to be processed and its actual geometric features on the machine tool, an accurate processing method model for the eccentric error of the rotatable indexable insert with a regular polygon is established, the coordinate parameters of the processed part in the horizontal and vertical directions of the bracket are obtained, and then the offset compensation amount is obtained for processing. The present invention obtains the eccentric error data of the processed part and uses these data for supplementary calculation, so as to improve the processing accuracy of the insert. After experiments, the geometric accuracy of the processed insert after the eccentric compensation is within #imgabs0#. This method is generally applicable to common rotatable indexable inserts with regular polygons, and has the characteristics of high efficiency, high accuracy, and wide applicability.

Description

Technical Field

[0001] The present invention relates to a method for eccentric error of machining regular polygon indexable inserts, belonging to the technical field of machine tool insert machining. Background Art

[0002] In the grinding process of inserts, when loading and clamping the blank of standard regular polygon indexable inserts, an auxiliary tooling is usually used to control the phase error of the rotation axis B-axis. However, in the actual clamping process, the geometric center of the tool often does not coincide with the rotation center of the machine tool spindle, inevitably causing clamping eccentricity. If this clamping error cannot be compensated correctly, it will result in incorrect machining dimensions of the parts, deviation of the center, etc. In addition, this problem has rarely been publicly studied in China, and the research depth is only limited to simple insert styles, and a systematic mathematical model has not been established. In order to ensure the accuracy of the finished product, the detection of the insert eccentric error is imminent. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to propose a method for eccentric error of machining regular polygon indexable inserts in view of the deficiencies of the prior art, establish a mathematical model for the detection of the eccentric error of regular polygon inserts, clamp the blank of regular polygon indexable inserts on the workpiece fixture of a peripheral grinding numerical control machine tool, and establish an accurate machining method model for the eccentric error of regular polygon indexable inserts according to the actual geometric characteristics of the blank of the regular polygon indexable insert to be machined and its position on the machine tool, obtain the coordinate parameters of the workpiece in the horizontal and vertical directions of the carriage, and then obtain the offset compensation amount for machining to ensure the accuracy of the finished product.

[0004] To solve the above technical problem, the present invention proposes a method for eccentric error of machining regular polygon indexable inserts, which clamps the blank of regular polygon indexable inserts on the workpiece fixture of a peripheral grinding numerical control machine tool, and according to the actual geometric characteristics of the blank of the regular polygon indexable insert to be machined and its position on the machine tool, an accurate machining method model for the eccentric error of regular polygon indexable inserts is established, the coordinate parameters of the workpiece in the horizontal and vertical directions of the carriage are obtained, and then the offset compensation amount is obtained for machining; the specific machining method steps are as follows:

[0005] 1.1 Extend three sides of the workpiece to form an isosceles triangle or extend four sides of the workpiece to form a parallelogram. Regular polygons are divided into regular odd-sided polygons and regular even-sided polygons; for regular odd-sided polygons, extend the adjacent side and the opposite side of the inner angle to form an isosceles triangle, and for regular even-sided polygons, extend two pairs of opposite sides to form a parallelogram. Regular triangles and regular quadrilaterals are special cases of regular odd-sided polygons and regular even-sided polygons.

[0006] 1.2 Determine the inner angle of the regular polygon , where N is the number of sides.

[0007] 1.3 Calculate the coordinates of the workpiece in the horizontal and vertical directions , K: Coordinates of the geometric center point of a regular odd-sided polygon , K is , ; Coordinates of the geometric center point of a regular even-sided polygon , K is , .

[0008] 1.4 Calculate the angle between the perpendicular line of each side of the workpiece to be machined and the X-axis .

[0009] 1.5 According to the above center point , K coordinates and angle , determine the offset compensation amount of each side according to the following formula:

[0010] ,

[0011] where , ,...., are the X-axis displacement compensation amounts when machining each surface.

[0012] The present invention obtains the eccentric error data of the workpiece to be machined and uses these data for supplementary calculation, thereby improving the machining accuracy of the cutting tool. After experiments, the geometric accuracy of the machined cutting tool is within This method is generally applicable to common indexable inserts of regular polygons and has the characteristics of high efficiency, high accuracy, wide applicability, etc. Brief Description of the Drawings

[0013] Figure 1 is a schematic diagram of the structure of each axis of the four-axis CNC peripheral grinder of the present invention.

[0014] Figure 2 is a schematic diagram of the structure of the tool holder of the present invention.

[0015] Figure 3 is a schematic diagram of the structure in Embodiment 1 of the present invention.

[0016] Figure 4 is a schematic diagram of an isosceles triangle established for a regular pentagon in Embodiment 1 of the present invention.

[0017] Figure 5 is a schematic diagram of the structure of a regular even-sided polygon of the present invention. Detailed Description of the Invention

[0018] 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.

[0019] Embodiment 1: As Figures 1-4As shown, in the method for eccentric error of the machined regular pentagon indexable insert, the blank of the regular pentagon indexable insert is clamped on the workpiece fixture of the peripheral grinding numerical control machine tool, and the regular pentagon indexable insert is machined relying on the peripheral grinding machine tool. The motion axes of the numerically controlled four-axis peripheral grinder are as Figure 1 shown, and the rotation axis C is the base axis of the rotation axis B. The grinding wheel spindle box is installed on the X-axis, and the X-axis workbench is installed on the Y-axis.

[0020] 1.1 Take two adjacent sides of the inner angle of the workpiece and its opposite side to establish an isosceles triangle, and determine the inner angle of the regular pentagon

[0021] = 108º.

[0022] 1.2 Pre-calibrate the distance from the sensor to the rotation center of the machine tool B-axis ; Rotate the B-axis clockwise to make side perpendicular to the distance sensor, and record the distance from the sensor to the plane ; Rotate the B-axis clockwise to make side perpendicular to the distance sensor, and record the distance from the sensor to the plane ; Rotate the B-axis clockwise to make side perpendicular to the distance sensor, and record the distance from the sensor to the plane .

[0023] 1.3 Calculate the distance from each side to the rotation center of the machine tool B-axis:

[0024]

[0025] Let the straight line equation of the three sides be

[0026]

[0027] For convenient calculation, let , and we get:

[0028]

[0029] From the geometric relationship, the slope can be obtained:

[0030]

[0031] From the distance formula from the straight line to the origin, we get: , and we get:

[0032]

[0033] Simultaneously solve to obtain the coordinates of point A ,

[0034] Simultaneously solve to obtain the coordinates of point B ,

[0035] Simultaneously solve to obtain the coordinates of point C .

[0036] Calculate the coordinates of J and K: , .

[0037] Step 11: Calculate the angles between the perpendiculars of each side and the X-axis :

[0038]

[0039] Calculate the offset compensation amounts of each side, that is, decompose J and K in the directions perpendicular to each side:

[0040]

[0041] Example 2: As Figures 1-4 shown, for the method of eccentric error of this machined equilateral indexable insert, the blank of the equilateral indexable insert is clamped on the workpiece fixture of the peripheral grinding numerical control machine tool. The equilateral indexable insert is processed relying on the peripheral grinding machine tool. The motion axes of the numerically controlled four-axis peripheral grinding are as Figure 1 shown. The rotation axis C is the base axis of the rotation axis B. The grinding wheel spindle box is installed on the X-axis, and the X-axis worktable is installed on the Y-axis. An equilateral triangle is a special example of a positive odd number. For an equilateral triangle, there is no need to extend the three sides to form an isosceles triangle.

[0042] 1.1 Pre-calibrate the distance from the sensor to the rotation center of the machine tool B-axis as ; Rotate the B-axis counterclockwise by 60°, make side a vertical to the right, and record the distance from the sensor to surface a ; Rotate the B-axis clockwise by 30° to make side b perpendicular to the right, and record the distance from the sensor to surface b ; Rotate the B-axis counterclockwise by 60°, make side c vertical to the right, and record the distance from the sensor to surface c .

[0043] 1.2 Calculate the distances from each side to the rotation center of the machine tool B-axis:

[0044]

[0045] Assume the straight-line equations of the three sides are:

[0046]

[0047] For convenient calculation, let , we get:

[0048] ,

[0049] From the geometric relationship, the slope can be obtained as: ;

[0050] From the distance formula from the line to the origin, we have: , we get:

[0051]

[0052] By combining we obtain ,

[0053] By combining we obtain the coordinates of point A

[0054] By combining we obtain the coordinates of point B .

[0055] Calculate the coordinates of J and K: , .

[0056] Step 11: Calculate the angles between the perpendiculars of each side and the X-axis :

[0057]

[0058] Calculate the offset compensation amounts of each side, that is, decompose J and K in the directions perpendicular to each side:

[0059]

[0060] Example 3: As Figures 1-2 , shown in Figure 5, for the method of eccentric error of this machined regular hexagonal indexable insert, the blank of the regular hexagonal indexable insert is clamped on the workpiece fixture of the peripheral grinding numerical control machine tool, and the regular hexagonal indexable insert relies on the peripheral grinding machine tool for machining. The motion axes of the numerically controlled four-axis peripheral grinder are as Figure 1 shown. The rotation axis C is the base axis of the rotation axis B. The grinding wheel spindle box is installed on the X-axis, and the X-axis worktable is installed on the Y-axis.

[0061] 1.1 Extend two groups of opposite sides of the regular hexagon to obtain the parallelogram ABCD, and determine the interior angle of the regular hexagon = 120º.

[0062] 1.2 Pre-calibrate the distance from the sensor to the rotation center of the machine tool B-axis as ; Rotate the B-axis clockwise make The edge is perpendicular to the distance sensor and records the distance from the sensor to Face distance ; Rotate B axis clockwise make The edge is perpendicular to the distance sensor and records the distance from the sensor to Face distance ; Rotate B axis clockwise make The edge is perpendicular to the distance sensor and records the distance from the sensor to Face distance ; Rotate B axis clockwise Make the d side perpendicular to the distance sensor and record the distance from the sensor to the d surface ;

[0063] 1.3 Calculate the distance from each side to the center of rotation of the machine tool B axis:

[0064]

[0065] Let the equations of the four sides be

[0066]

[0067] To facilitate calculation, ,have to:

[0068]

[0069] From the geometric relationship, we can get the slope:

[0070]

[0071] From the distance formula from a straight line to the origin, we get: ,have to:

[0072]

[0073] Lian Li Get the coordinates of point B .

[0074] Lian Li Get the coordinates of point C .

[0075] Lian Li Get the coordinates of point D .

[0076] Lian Li Get the coordinates of point A .

[0077] Calculate the J and K coordinates:

[0078] The eleventh step: Calculate the angles between the perpendiculars of each side and the X-axis :

[0079] )

[0080] Calculate the offset compensation amount of each side, that is, decompose J and K in the direction perpendicular to each side:

[0081]

[0082] 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 gist 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 eccentric error of machining regular polygon indexable inserts, characterized in that: Clamp the regular polygon indexable insert blank on the workpiece fixture of the peripheral grinding numerical control machine tool. According to the regular polygon indexable insert blank to be machined and its actual geometric characteristics on the machine tool, establish an accurate machining method model for the eccentric error of the regular polygon indexable blade, obtain the coordinate parameters of the workpiece in the horizontal and vertical directions of the bracket, and then obtain the offset compensation amount for machining. The specific steps of the machining method are as follows: 1.1 Extend three sides of the workpiece to form an isosceles triangle or extend four sides to form a parallelogram. Regular polygons are divided into regular odd-sided polygons and regular even-sided polygons. For regular odd-sided polygons, extend the adjacent side and the opposite side of the interior angle to form an isosceles triangle. For regular even-sided polygons, extend two pairs of opposite sides to form a parallelogram. 1.2 Determine the interior angle of a regular polygon ; 1.3 Calculate the coordinates of the geometric center points of the cross-sections of the workpiece in the horizontal and vertical directions , K: Coordinates of a regular odd-sided polygon , K is , , where are the vertex coordinates of the triangle formed during the calculation of a regular odd-sided polygon; Coordinates of a regular even-sided polygon , K is , , Among them, are the vertex coordinates of the quadrilateral formed during the calculation for a regular even-sided polygon; 1.4 Calculate the angle between the perpendicular line of each side of the workpiece and the X-axis ; 1.5 According to the above geometric center point , K coordinates and included angle , determine the offset compensation amount of each side according to the following formula: ， Among them 、 、....、 are the X-axis displacement compensation amounts for machining each surface.

2. The method for eccentric error of machining regular polygon indexable inserts according to claim 1, characterized in that: The interior angle of the regular polygon , where N is the number of sides.

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