Method and tooling for five-axis fine milling of end face reference surface of cast aluminum pattern block

Abstract

The application discloses a method and a tool for five-axis fine milling of an end face reference surface of a cast aluminum pattern block, and relates to the technical field of tire mold processing. The method can quantitatively correct the clamping posture deviation of the cast aluminum pattern block, based on a row*column grid distribution of a plurality of measuring points, through the deviation of actual values and ideal values of the measuring points in the Z-axis direction, the theoretical rotation angle of the cast aluminum pattern block for alignment can be accurately calculated, the posture is corrected through twice rotation transformation, and the coaxiality and perpendicularity of the end face reference surface and the cavity surface are ensured. The tool is characterized in that two positioning blocks are relatively moved in the first linear direction and simultaneously fit the assembly outer circle of the cast aluminum pattern block, and the two clamping blocks are synchronously close to each other in the second linear direction to contact and clamp the parting surface line of the cast aluminum pattern block from both sides, the positioning of the cast aluminum pattern block in the Z-axis direction is realized, the clamping positioning is accurate and reliable, and the tool can be adapted to cast aluminum pattern blocks of different specifications and has high universality.

Description

Technical Field

[0001] This invention relates to the field of tire mold processing technology, specifically to a method and tooling for five-axis precision milling of the end face reference surface of a cast aluminum tread block. Background Technology

[0002] As an important component of tire tread forming molds, the machining accuracy of the end face reference surface (upper and lower diameter end face) of cast aluminum pattern blocks directly affects the sealing performance, coaxiality, and forming quality of the tire shoulder area when the mold is closed, and also affects the symmetry and position of the cavity curve during the machining process.

[0003] Currently, the industry typically uses bench vises to clamp and machine the end face reference surface of cast aluminum patterned blocks, which has the following drawbacks: 1. Traditional machining methods cannot quantitatively detect and correct deviations, making it difficult to guarantee the coaxiality and perpendicularity of the end face reference surface and the cavity surface; 2. Low machining efficiency and poor consistency; 3. Insufficient positioning tooling accuracy. Existing tooling mostly uses a single reference for positioning, which cannot simultaneously meet the requirements of assembly outer circle centering, parting surface positioning, and clamping. Positioning errors are prone to accumulate, further reducing machining accuracy.

[0004] Therefore, developing a method and tooling that can quantitatively detect and correct the gripping posture deviation of cast aluminum patterned blocks and achieve high-precision machining of the end face reference surface is an urgent problem to be solved at this stage. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a method and tooling for five-axis precision milling of the end face reference surface of cast aluminum tread blocks, which can effectively solve the problems of low machining accuracy of the end face reference surface of cast aluminum tread blocks, inability to quantify and correct posture errors, and insufficient tooling positioning accuracy, thereby improving the mold closing accuracy of tire molds and the tire forming quality.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: On one hand, the present invention provides a method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, comprising the following steps: S1: Select a pattern based on the pattern surface of the cast aluminum patterned block. Line × Column grid distribution Measurement points ,in, Ideally, the patterned surface faces upwards, the rows in the grid are parallel to the Y-axis, and the columns are parallel to the X-axis. The measurement points... The ideal values ​​on the Z-axis are respectively The row length of the grid is The column length is ; S2: Clamp the cast aluminum patterned block and position it in the Z-axis direction, then sequentially measure the actual values ​​of all the measurement points on the Z-axis. ; S3: Calculate the deviation between the actual value and the ideal value at each measurement point. ; S4: Calculate the average deviation values ​​of the measurement points in the two outermost rows, respectively. and Based on the average deviation value, the height difference between the actual value and the ideal value of the measurement point in the row direction is calculated as follows: To obtain the theoretical angle difference in the row direction. ; S5: Calculate the average deviation values ​​of the measurement points in the outermost two columns, respectively. The height difference between the actual value and the ideal value of the measurement point in the column direction is calculated based on the average deviation value. Obtain the theoretical angle difference in the column direction. ; S6: Rotate the cast aluminum patterned block around the X-axis Angle, then rotate around the Y-axis The angle is adjusted to achieve alignment before proceeding with the machining process of the end face reference surface.

[0007] As a preferred technical solution, in step S1, under ideal conditions, the ideal center of one end diameter of the cast aluminum patterned block is O; in step S2, three points are randomly selected on one end diameter of the cast aluminum patterned block to calculate the actual center as o, and the ideal value is adjusted based on the difference between the ideal center O and the actual center o on the Z-axis. .

[0008] As a preferred technical solution, in step S2, the cast aluminum patterned block is clamped on a five-axis machine tool, and the five-axis machine tool is equipped with a contact probe to measure the actual value of the measurement point.

[0009] As a preferred technical solution, in step S1, .

[0010] As a preferred technical solution, in step S6, the cast aluminum patterned block rotates around the X-axis. The angle transformation matrix is The cast aluminum patterned block rotates around the Y-axis. The angle transformation matrix is .

[0011] As a preferred technical solution, the cast aluminum patterned block rotates around the X-axis. The angle then rotates around the Y-axis The total transformation matrix of the angle is .

[0012] Secondly, the present invention provides a tooling for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, applied to the aforementioned method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, comprising: Base plate; Two positioning blocks are provided on the base plate, and one positioning block can move relative to the other positioning block along a first linear direction; each positioning block is provided with a positioning surface. Two clamping blocks are provided on the base plate, and the two clamping blocks can move closer or further away from each other synchronously along a second straight line direction; each clamping block is provided with a clamping surface; the first straight line direction is perpendicular to the second straight line direction. Ideally, the first straight line direction is parallel to the Y-axis; the second straight line direction is parallel to the X-axis; the positioning surface fits into the outer circle of the cast aluminum patterned block, and the positioning surface is perpendicular to the Y-axis; the clamping block is in line contact with the parting surface of the cast aluminum patterned block, and the generatrix of the line contact is parallel to the Y-axis.

[0013] As a preferred technical solution, the base plate is provided with a fixed positioning seat, a first lead screw and a positive and negative lead screw, one positioning block is provided on the fixed positioning seat, the nut of the first lead screw is provided with a movable positioning seat, and the other positioning block is provided on the movable positioning seat; both nuts of the positive and negative lead screws are provided with clamping seats, and the two clamping blocks are respectively provided on the two clamping seats.

[0014] As a preferred technical solution, the clamping block is configured as a roller, which is rotatably mounted on the clamping seat, and the outer peripheral surface of the roller forms the clamping surface.

[0015] As a preferred technical solution, the base plate is provided with a first guide rail and a second guide rail. The first guide rail is parallel to the first lead screw, and a first moving block that can move along the first guide rail is provided. The movable positioning seat is fixedly connected to the first moving block. The second guide rail is parallel to the positive and negative lead screws, and a second moving block that can move along the second guide rail is provided. The clamping seat is fixedly connected to the second moving block. And / or, the cast aluminum patterned block is provided with a centering feature point.

[0016] The beneficial effects of this invention are as follows: 1. The method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to the present invention can quantitatively correct the clamping posture deviation of the cast aluminum patterned block, based on... Line × Column grid distribution By measuring the deviation between the actual and ideal values ​​of each measurement point in the Z-axis direction, the theoretical rotation angle for alignment of the cast aluminum pattern block can be accurately calculated. The posture of the cast aluminum pattern block is corrected through two rotation transformations to ensure the coaxiality and perpendicularity of the end face reference surface and the cavity surface. High-precision machining of the end face reference surface is achieved by using five-axis machine tool linkage. The flatness and parallelism tolerances of the end face reference surface are controllable, and the machining consistency of pattern blocks in different batches is significantly improved.

[0017] 2. The tooling for the five-axis precision milling end face reference surface of the cast aluminum patterned block of the present invention uses two positioning blocks to move relative to each other in the first linear direction and simultaneously fit with the assembly outer circle of the cast aluminum patterned block. The two clamping blocks move closer to each other in the second linear direction and can contact and clamp the parting surface line of the cast aluminum patterned block from both sides. This can realize the positioning of the cast aluminum patterned block in the Z-axis direction. The clamping and positioning are accurate and reliable, and it can be adapted to cast aluminum patterned blocks of different specifications, with strong versatility. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a 3-row × 3-column grid distribution of an embodiment of a method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to the present invention; Figure 2 This is a schematic diagram of the overall structure of a tooling for a five-axis precision milling reference surface of a cast aluminum patterned block according to the present invention. Figure 3 for Figure 2 Front view; Figure 4 This is a schematic diagram of the structure of a cast aluminum patterned block.

[0019] In the figure: 1-base plate, 11-first guide rail, 12-second guide rail, 2-positioning block, 21-positioning surface, 3-clamping block, 31-clamping surface, 41-fixed positioning seat, 42-movable positioning seat, 43-first lead screw, 44-positive and negative lead screw, 5-cast aluminum patterned block, 51-end face reference surface, 52-diameter, 53-assembly outer circle, 54-parting surface, 55-centering feature point. Detailed Implementation

[0020] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0021] Firstly, please refer to Figure 1 and Figure 4 This invention provides an embodiment of a method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, comprising the following steps: S1: Select a pattern based on the pattern surface of the cast aluminum patterned block 5. Line × Column grid distribution Measurement points ,in, Ideally, the patterned surface should face upwards, with rows in the grid parallel to the Y-axis and columns parallel to the X-axis, and measurement points... The ideal values ​​on the Z-axis are respectively The row length of the grid is The column length is ; In this embodiment, In other embodiments, and Other values ​​may also be used, based on the theoretical rotation angle for accurate measurement and calculation of the alignment of the cast aluminum patterned block; It should be noted that, under ideal conditions, the ideal center of the diameter 52 at one end of the cast aluminum patterned block 5 is O; in step S2, according to the principle of three points determining a circle, three points are randomly selected on the diameter 52 at one end of the cast aluminum patterned block 5 to calculate the actual center as o. Based on the difference between the ideal center O and the actual center o on the Z-axis, the ideal value is adjusted accordingly based on this difference. This achieves compensation for the deviation of the circle center.

[0022] S2: Clamp the cast aluminum patterned block 5 and position it along the Z-axis. Measure the actual values ​​of all measurement points on the Z-axis sequentially. ; Specifically, the cast aluminum patterned block 5 is clamped on a five-axis machine tool, which is equipped with a contact probe capable of accurately measuring each measurement point. The actual value; furthermore, when using a contact probe for measurement, based on the ideal state of each measurement point. The position of each measurement point is determined by the distance from each edge of the patterned surface, ensuring that the position of each measurement point during measurement is consistent with the position of each measurement point under ideal conditions.

[0023] S3: Calculate the deviation between the actual value and the ideal value at each measurement point. .

[0024] S4: Calculate the average deviation values ​​of the measurement points in the two outermost rows, respectively. Based on the average deviation value, the height difference between the actual value and the ideal value of the measurement point in the row direction is calculated as follows: To obtain the theoretical angle difference in the row direction. .

[0025] S5: Calculate the average deviation values ​​of the measurement points in the outermost two columns, respectively. The height difference between the actual value and the ideal value of the measurement point in the column direction is calculated based on the average deviation value. Obtain the theoretical angle difference in the column direction. .

[0026] S6: Rotate the cast aluminum patterned block 5 around the X-axis Angle, then rotate around the Y-axis After aligning the angle, the machining process of the end face reference surface 51 is carried out. Specifically, the cast aluminum patterned block 5 rotates around the X-axis. The angle transformation matrix is ; Cast aluminum patterned block 5 rotates around the Y-axis The angle transformation matrix is ; Furthermore, the cast aluminum patterned block 5 rotates around the X-axis. The angle then rotates around the Y-axis The total transformation matrix of the angle is .

[0027] Secondly, please refer to Figures 2-4 The present invention provides a tooling for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, which is applied to the aforementioned method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block. It includes a base plate 1, two positioning blocks 2 and two clamping blocks 3, all of which are disposed on the base plate 1. One positioning block 2 can move relative to another positioning block 2 along a first straight line direction; the positioning block 2 is provided with a positioning surface 21 that matches the assembly outer circle 53 of the cast aluminum patterned block 5; the two clamping blocks 3 can move closer or further away from each other synchronously along a second straight line direction; the clamping block 3 is provided with a clamping surface 31 that matches the parting surface 54 of the cast aluminum patterned block 5; the first straight line direction and the second straight line direction are perpendicular to each other. Ideally, when the cast aluminum patterned block 5 is clamped and positioned to the desired location, the first straight line direction is parallel to the Y-axis; the second straight line direction is parallel to the X-axis; the positioning surface 21 is in contact with the outer assembly circle 53 of the cast aluminum patterned block 5, and the positioning surface 21 is perpendicular to the Y-axis; the clamping block 3 is in line contact with the parting surface 54 of the cast aluminum patterned block 5, and the generatrix of the line contact is parallel to the Y-axis; so that before clamping the cast aluminum patterned block 5, it is only necessary to install the base plate 1 on the five-axis machine tool and keep the installation position of the base plate 1 consistent with the ideal state. When clamping the cast aluminum patterned block 5, under the combined action of the positioning surface 21 and the clamping surface 31, the cast aluminum patterned block 5 can be positioned in the Z-axis direction.

[0028] Specifically, please refer to Figure 2 and Figure 3The base plate 1 is provided with a fixed positioning seat 41, a first lead screw 43 and a forward and reverse lead screw 44. A positioning block 2 is provided on the fixed positioning seat 41. A movable positioning seat 42 is provided on the nut of the first lead screw 43. Another positioning block 2 is provided on the movable positioning seat 42. Under the drive of the first lead screw 43, the movable positioning seat 42 and a positioning block 2 can move in the direction of approaching or moving away from the other positioning block 2. Both nuts of the forward and reverse lead screw 44 are provided with clamping seats. Two clamping blocks 3 are respectively provided on the two clamping seats. Under the drive of the forward and reverse lead screw 44, the clamping blocks 3 on the two clamping seats can move closer or further away from each other synchronously.

[0029] Further, please refer to Figure 2 and Figure 3 The clamping block 3 is a roller, which is rotatably mounted on the clamping seat. The outer circumferential surface of the roller forms a clamping surface 31, ensuring that the roller makes line contact with the parting surface 54 of the cast aluminum patterned block 5.

[0030] In this embodiment, please refer to Figure 2 The base plate 1 is provided with a first guide rail 11 and a second guide rail 12. The first guide rail 11 is parallel to the first lead screw 43. The first guide rail 11 is provided with a first moving block that can move along it. The movable positioning seat 42 is fixedly connected to the first moving block to ensure that the movable positioning seat 42 moves stably along the first straight line direction. Similarly, the second guide rail 12 is parallel to the positive and negative lead screws 44. The second guide rail 12 is provided with a second moving block that can move along it. The clamping seat is fixedly connected to the second moving block to ensure that the two clamping blocks 3 move towards or away from each other stably and synchronously along the second straight line direction.

[0031] For further explanation, please refer to Figure 4 The cast aluminum patterned block 5 can also be provided with a centering feature point 55. On the one hand, when clamping the cast aluminum patterned block 5, the centering feature point 55 can improve the positional accuracy when gripping and effectively reduce the range of adjustment of the attitude of the cast aluminum patterned block 5. On the other hand, the centering feature point 55 is also the machining reference of the end face reference surface 51, further improving the machining accuracy.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations; any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, characterized in that, Includes the following steps: S1: Select a pattern based on the pattern surface of the cast aluminum patterned block (5). Line × Column grid distribution Measurement points ,in, ; Ideally, the patterned surface should face upwards, the rows in the grid should be parallel to the Y-axis, and the columns should be parallel to the X-axis. The measurement points... The ideal values ​​on the Z-axis are respectively The row length of the grid is The column length is ; S2: Clamp the cast aluminum patterned block (5) and position it in the Z-axis direction, and measure the actual values ​​of all the measurement points on the Z-axis in sequence. ; S3: Calculate the deviation between the actual value and the ideal value at each measurement point. ; S4: Calculate the average deviation values ​​of the measurement points in the two outermost rows, respectively. and The height difference in the row direction between the actual value and the ideal value of the measurement point is calculated based on the average deviation value. To obtain the theoretical angle difference in the row direction. ; S5: Calculate the average deviation values ​​of the measurement points in the outermost two columns, respectively. and The height difference in the column direction between the actual value and the ideal value of the measurement point is calculated based on the average deviation value. Obtain the theoretical angle difference in the column direction. ; S6: Rotate the cast aluminum patterned block (5) around the X-axis Angle, then rotate around the Y-axis After aligning the angle, the end face reference surface (51) is processed.

2. The method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 1, characterized in that, In step S1, under ideal conditions, the ideal center of one end diameter (52) of the cast aluminum patterned block (5) is O; in step S2, three points are randomly selected on one end diameter (52) of the cast aluminum patterned block (5) to calculate the actual center as o, and the ideal value is adjusted based on the difference between the ideal center O and the actual center o on the Z-axis. .

3. The method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 1, characterized in that, In step S2, the cast aluminum patterned block (5) is clamped on a five-axis machine tool, which is equipped with a contact probe to measure the actual value of the measurement point.

4. A method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 1 or 2, characterized in that, In step S1, .

5. The method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 4, characterized in that, In step S6, the cast aluminum patterned block (5) rotates around the X-axis. The angle transformation matrix is The cast aluminum patterned block (5) rotates around the Y-axis. The angle transformation matrix is .

6. The method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 5, characterized in that, The cast aluminum patterned block (5) rotates around the X-axis The angle then rotates around the Y-axis The total transformation matrix of the angle is .

7. A tooling for five-axis precision milling of the end face reference surface of a cast aluminum patterned block, applied to the method for five-axis precision milling of the end face reference surface of a cast aluminum patterned block as described in any one of claims 1-6, characterized in that, include: Base plate (1); Two positioning blocks (2) are provided on the base plate (1). One positioning block (2) can move relative to the other positioning block (2) along a first straight line direction. The positioning block (2) is provided with a positioning surface (21). Two clamping blocks (3) are provided on the base plate (1). The two clamping blocks (3) can move closer to or further away from each other synchronously along the second straight line direction. The clamping blocks (3) are provided with clamping surfaces (31). The first straight line direction is perpendicular to the second straight line direction. Ideally, the first straight line direction is parallel to the Y-axis; the second straight line direction is parallel to the X-axis; the positioning surface (21) fits against the outer circle (53) of the cast aluminum patterned block (5), and the positioning surface (21) is perpendicular to the Y-axis; the clamping block (3) is in line contact with the parting surface (54) of the cast aluminum patterned block (5), and the generatrix of the line contact is parallel to the Y-axis.

8. The tooling for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 7, characterized in that, The base plate (1) is provided with a fixed positioning seat (41), a first lead screw (43) and a forward and reverse lead screw (44). One positioning block (2) is provided on the fixed positioning seat (41). The nut of the first lead screw (43) is provided with a movable positioning seat (42). The other positioning block (2) is provided on the movable positioning seat (42). Both nuts of the forward and reverse lead screw (44) are provided with clamping seats. The two clamping blocks (3) are respectively provided on the two clamping seats.

9. The tooling for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 8, characterized in that, The clamping block (3) is configured as a roller, which is rotatably mounted on the clamping seat, and the outer circumferential surface of the roller forms the clamping surface (31).

10. The tooling for five-axis precision milling of the end face reference surface of a cast aluminum patterned block according to claim 8, characterized in that, The base plate (1) is provided with a first guide rail (11) and a second guide rail (12). The first guide rail (11) is parallel to the first lead screw (43). The first guide rail (11) is provided with a first moving block that can move along it. The movable positioning seat (42) is fixedly connected to the first moving block. The second guide rail (12) is parallel to the positive and negative lead screws (44). The second guide rail (12) is provided with a second moving block that can move along it. The clamping seat is fixedly connected to the second moving block. And / or, the cast aluminum patterned block (5) is provided with a centering feature point (55).

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