A diamond tool feature recognition method based on guide motor current signal

Abstract

A diamond tool feature recognition method based on a guide rail motor current signal relates to a diamond tool processing method. A diamond tool that has completed single crystal diamond blank welding is fixed on a tool holder, and the set arc center coincides with the center of a rotary table; the feed rail drives the tool tip to contact the grinding wheel, and the rotary table swings back and forth; the feed rail feeds forward to complete rough grinding; the feed rail feeds at a constant rate, the rotary table swings at a constant speed, and the current signal of the guide rail motor is collected; the current signal corresponding to the tool within one cycle of the reciprocating swing of the rotary table is processed, and the features of each point on the arc blade are quantified, and the grinding pressure and grinding speed are set according to the feature signal value; and fine grinding is performed. By collecting and analyzing the current signal of the guide rail motor, the feature signals of each point on the arc blade are obtained, and the softness and hardness of each point are quantified, without the need for diamond crystal orientation, thereby improving the processing efficiency and accuracy of the tool.

Description

Technical Field

[0001] The invention relates to a diamond tool processing method, in particular to a diamond tool feature recognition method based on a guide rail motor current signal, and belongs to the technical field of ultra-precision manufacturing equipment. Background Art

[0002] In recent years, ultra-precision cutting technology has been used more and more widely. As an indispensable tool in ultra-precision cutting technology, the demand for single-crystal diamond tools has also increased year by year. Arc-edged diamond tools are the most commonly used single-crystal diamond tools. The waviness accuracy of the arc-edged tool directly determines the surface accuracy of the machined parts. Therefore, the processing of the arc-edged tool has very high requirements, usually needing to reach the sub-micron level. However, diamond crystals have strong anisotropy, and the material hardness of each position of the diamond crystal is different, that is, the characteristics of each position are different, which greatly increases the processing difficulty and processing time of arc-edged diamond tools.

[0003] Diamond tool feature identification is a preliminary preparation for tool grinding, which has a great impact on the subsequent processing accuracy and efficiency. At present, domestic and foreign diamond tool manufacturers still use the diamond crystal orientation method for tool feature identification, which requires orienting the crystal and then roughly judging the characteristics of each position of the tool based on experience. This is not only cumbersome and inefficient, but also introduces two errors after welding and installation of the oriented crystal. The tool features cannot be accurately identified, let alone quantified, and the material removal efficiency is uncontrollable, resulting in the overall processing accuracy and efficiency of arc-edged diamond tools being unable to be improved.

[0004] In summary, there is an urgent need for a targeted, fast and accurate diamond tool feature recognition method to solve the current problem of difficult feature recognition of arc-edged diamond tools, which is of great significance for the high-precision and high-efficiency processing of diamond tools. Summary of the invention

[0005] In order to overcome the shortcomings of the background technology, the present invention provides a diamond tool feature recognition method based on the guide motor current signal. The method acquires the feature signal of each point on the circular arc blade of the diamond tool by collecting and analyzing the guide motor current signal. The hardness of each point is quantitatively represented, and no diamond crystal orientation is required, thereby improving the processing efficiency and precision of the tool.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A diamond tool feature recognition method based on a guide rail motor current signal, the applied machine tool comprises a machine tool base as a bottom platform, a transverse slide rail and a feed guide rail vertically arranged and installed on the surface of the machine tool base, a spindle component is installed on the transverse slide rail, the spindle component drives and installs a grinding wheel, a CCD camera is fixed above the grinding wheel, the feed guide rail controls the feeding action through the guide rail motor, a rotary table is installed on the feed guide rail, a tool holder is installed at an eccentric position on the rotary table, and the tool holder is used to clamp and fix the diamond tool;

[0008] The feature recognition method comprises the following steps:

[0009] S1. The diamond tool that has completed the welding of the single crystal diamond blank is fixedly mounted on the tool holder to ensure that the center of the arc set by the diamond tool coincides with the center of the rotary table;

[0010] S2. Adjust the lateral position of the spindle component so that the rotating surface of the grinding wheel disc corresponds to the diamond tool, operate the feed guide rail to drive the diamond tool to approach the grinding wheel disc, and use the CCD camera to observe until the tip of the diamond tool contacts the grinding wheel disc, and start the rotary table to drive the diamond tool to swing back and forth;

[0011] S3. Control the feed rail to feed forward until the tip of the diamond tool is ground into a circular arc edge, and all points on the circular arc edge can participate in the grinding, thus completing the rough grinding of the diamond tool;

[0012] S4. Keep the feed rail at a constant rate, control the rotary table to swing at a constant speed, use the computer to retrieve the current information of the rail motor, and collect the current signal of the rail motor within one cycle of the reciprocating swing of the rotary table;

[0013] S5. Process the current signal of the guide motor, filter out the high-frequency part greater than 10HZ in the signal, and then divide the signal into several segments according to the time interval, respectively obtain the average value of the signal in each segment, and then correspond the midpoint of each time segment to the position on the circular arc edge of the diamond tool one by one, and obtain the current signal I of the guide motor corresponding to the diamond tool at these positions during one cycle of the reciprocating swing of the rotary table. The value of the current signal I is positively correlated with the hardness of the circular arc edge of the diamond tool. When the diamond material removal rate and the grinding speed are unchanged, the characteristic signal value of the diamond tool is:

[0014] e=k1*f1*v / S

[0015] In the formula, S represents the diamond material removal rate, f1 represents the grinding pressure, v represents the grinding speed, and k1 is the proportionality coefficient.

[0016] The relationship between the output f2 of the guide motor and the current signal I is f2=k2*I, where k2 is the proportional coefficient, and the grinding pressure f1 and the output f2 of the guide motor are regarded as the action force and reaction force, so the characteristic signal value of the diamond tool is:

[0017] e=k1*k2*I*v / S

[0018] The formula is dimensionless, where the proportional coefficients k1, k2 and the constant grinding speed v are multiplied together, and the product is the characteristic signal correction coefficient K, then the characteristic signal value of the diamond tool is:

[0019] e=K*I / S

[0020] The characteristics of each point on the circular arc edge of the diamond tool are quantified by the current signal I of the guide motor, and the grinding pressure f1 and the grinding speed v are set according to the characteristic signal value e in the subsequent diamond tool grinding process;

[0021] S6. Control the feed guide rail to complete the tool retraction action and carry out the subsequent fine grinding of the diamond tool.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: the traditional method requires first orienting the diamond crystal, then welding the diamond to the tool handle, and then installing it on the tool holder. After two errors are introduced by welding and installation, the direction of the tool finally installed on the machine tool has an error. However, the present invention does not require diamond crystal orientation, and directly identifies the characteristics of the diamond on the machine tool after the tool is welded and installed. Therefore, the two errors introduced by welding and installation in the traditional method can be eliminated. By collecting and analyzing the current signal of the guide motor, the characteristic signal of each point on the circular arc blade of the diamond tool is obtained, and the softness and hardness of each point are quantitatively represented, which effectively improves the processing efficiency and processing accuracy of the circular arc blade of the diamond tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is an overall structural diagram of a machine tool used in the feature recognition method of the present invention. DETAILED DESCRIPTION

[0024] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] The traditional diamond crystal orientation process is cumbersome, which will increase the time of preliminary preparation work and reduce the tool processing efficiency. After the diamond crystal is oriented, there are two problems of introducing installation errors during welding and installation, which leads to reduced tool processing accuracy. In addition, diamond crystal orientation can only reflect the crystal plane and crystal phase of the crystal, and cannot directly and quantitatively reflect the characteristics of the crystal material, resulting in the inability to adjust the processing parameters in a targeted and accurate manner according to the characteristics of the crystal material.

[0026] The present invention proposes a diamond tool feature recognition method based on the guide rail motor current signal, and the machine tool reference Figure 1 As shown, it includes a machine tool base 1 as a bottom platform, a transverse slide rail 2 and a feed guide rail 9 arranged vertically on the surface of the machine tool base 1, a spindle component 3 is installed on the transverse slide rail 2, and a grinding wheel 4 is driven and installed on the spindle component 3. The spindle component 3 can move left and right along the transverse slide rail 2 to adjust the lateral position of the grinding wheel 4 and the diamond tool 6. A CCD camera 5 is fixed above the grinding wheel 4. The feed guide rail 9 controls the feeding action through a guide rail motor 10. A rotary table 8 is installed on the feed guide rail 9. A tool holder 7 is installed at an eccentric position on the rotary table 8. The tool holder 7 is used to clamp and fix the diamond tool 6. The feed guide rail 9 can control the rotary table 8 to move forward and backward to adjust the longitudinal position of the diamond tool 6 and the grinding wheel 4.

[0027] The feature recognition method comprises the following steps:

[0028] S1. The diamond tool 6 that has been welded to the single crystal diamond blank is fixedly mounted on the tool holder 7, ensuring that the center of the arc set by the diamond tool 6 coincides with the center of the rotary table 8. The rotary table 8 and the feed guide rail 9 are ultra-precision components. The radial rotation accuracy of the rotary table 8 is higher than 0.1μm / 120°, the positioning accuracy of the feed guide rail 9 is higher than 0.1μm / 100mm, and the current feedback resolution of the guide motor 10 is higher than 1mA;

[0029] S2. Adjust the lateral position of the spindle component 3 so that the rotating surface of the grinding wheel 4 corresponds to the diamond tool 6, operate the feed guide 9 to drive the diamond tool 6 to approach the grinding wheel 4, and use the CCD camera 5 to observe until the tip of the diamond tool 6 contacts the grinding wheel 4, and the grinding sound is heard, and start the rotary table 8 to drive the diamond tool 6 to swing back and forth, and the swing angle range is -60° to +60°;

[0030] S3. Control the feed rail 9 to feed forward until the tip of the diamond tool 6 is ground into a circular arc edge, and each point on the circular arc edge can participate in the grinding, that is, the rough grinding of the diamond tool 6 is completed;

[0031] S4. Keep the feed rail 9 at a constant rate, the rate range is 0.05-0.3μm / s, control the rotary table 8 to swing at a constant speed, the rate range is 0.5-3° / s, use the computer to retrieve the current information of the guide motor 10, and collect the current signal of the guide motor 10 during the reciprocating swing of the rotary table 8 in one cycle;

[0032] S5. Process the current signal of the guide motor 10, filter out the high-frequency part (>10HZ) in the signal, and then divide the signal into several segments according to the time interval, the time interval range is 1-10s, and respectively obtain the average value of the signal in each segment, and then correspond the midpoint of each time segment to the position on the circular arc edge of the diamond tool 6 one by one, so as to obtain the current signal I of the guide motor 10 corresponding to the diamond tool 6 at these positions during one cycle of the reciprocating swing of the rotary table 8, wherein the value of the current signal I is positively correlated with the hardness of the circular arc edge of the diamond tool 6, that is, the point with a relatively large value in the current signal I corresponds to the position with a higher hardness on the circular arc edge of the diamond tool 6, and the point with a relatively small value in the current signal I corresponds to the position with a lower hardness on the circular arc edge of the diamond tool 6.

[0033] Because the diamond material removal rate S is approximately proportional to the grinding pressure f1 and the grinding speed v, and approximately inversely proportional to the characteristic e of the diamond material (the hardness of each point), that is, S = k1*f1*v / e, where k1 is the proportionality coefficient.

[0034] When the diamond material removal rate S and the grinding speed v remain unchanged, the characteristic e of the diamond material only corresponds to the grinding pressure f1. The characteristic signal value of the diamond tool 6 can be obtained by changing the formula:

[0035] e=k1*f1*v / S

[0036] That is, the greater the required grinding pressure f1, the higher the diamond hardness, and vice versa, the lower the diamond hardness. The grinding pressure f1 and the output f2 of the guide motor 10 can be regarded as a pair of action and reaction forces, which are equal in magnitude and opposite in direction. The output f2 of the guide motor 10 is proportional to the value of the current signal I of the guide motor 10, that is, f2=k2*I, where k2 is the proportionality coefficient. Therefore, the characteristic signal value of the diamond tool 6 is:

[0037] e=k1*k2*I*v / S

[0038] The formula is dimensionless, where the proportional coefficients k1, k2 and the constant grinding speed v are multiplied together, and the product is the characteristic signal correction coefficient K, then the characteristic signal value of the diamond tool 6 is:

[0039] e=K*I / S

[0040] In this way, the characteristics of each point on the circular arc edge of the diamond tool 6 can be quantitatively expressed through the current signal I of the guide motor 10. In the subsequent grinding process of the diamond tool 6, the grinding pressure f1 and the grinding speed v can be set according to the characteristic signal value e to accurately control the material removal at each position of the circular arc edge of the diamond tool 6, and finally a high-precision tool is processed;

[0041] S6. Control the feed guide rail 9 to complete the tool retraction action and perform subsequent fine grinding of the diamond tool 6.

[0042] By collecting and analyzing the current signal of the guide motor 10, the present invention can efficiently and directly obtain the characteristic signal of each point on the circular arc blade of the diamond tool 6, that is, a quantitative representation of the softness and hardness of each point. This can not only save the traditional diamond crystal orientation step and save time, but also improve the accuracy of feature recognition, and further improve the processing efficiency and processing accuracy of the circular arc blade of the diamond tool 6.

[0043] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other forms of assembly without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and range of equivalents of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0044] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A diamond tool feature recognition method based on guide rail motor current signal, characterized in that: The applied machine tool comprises a machine tool base (1) as a bottom platform, a transverse slide rail (2) and a feed guide rail (9) arranged vertically and mounted on the surface of the machine tool base (1); a spindle component (3) is mounted on the transverse slide rail (2); the spindle component (3) drives a grinding wheel (4) to be mounted; a CCD camera (5) is mounted and fixed above the grinding wheel (4); the feed guide rail (9) controls the feeding action through a guide rail motor (10); a rotary table (8) is mounted on the feed guide rail (9); a tool holder (7) is mounted at an eccentric position on the rotary table (8); and the tool holder (7) is used to clamp and fix a diamond tool (6); The feature recognition method comprises the following steps: S1. The diamond tool (6) having completed welding of the single crystal diamond blank is fixedly mounted on the tool holder (7) to ensure that the center of the arc set by the diamond tool (6) coincides with the center of the rotary table (8); S2. Adjust the lateral position of the spindle component (3) so that the rotating surface of the grinding wheel (4) corresponds to the diamond tool (6), operate the feed guide rail (9) to drive the diamond tool (6) to approach the grinding wheel (4), use the CCD camera (5) to observe until the tip of the diamond tool (6) contacts the grinding wheel (4), and start the rotary table (8) to drive the diamond tool (6) to swing back and forth; S3. Control the feed rail (9) to feed forward until the tip of the diamond tool (6) is ground into a circular arc edge, and each point on the circular arc edge can participate in the grinding to complete the rough grinding of the diamond tool (6); S4. Maintain the feed rail (9) at a constant rate of feed, control the rotary table (8) to swing at a constant speed, use the computer to retrieve the current information of the guide motor (10), and collect the current signal of the guide motor (10) during a reciprocating swing cycle of the rotary table (8); S5. Process the current signal of the guide motor (10), filter out the high-frequency part greater than 10 Hz in the signal, and then divide the signal into several segments according to the time interval, respectively obtain the average value of the signal in each segment, and then correspond the midpoint of each time segment to the position on the circular arc blade of the diamond tool (6) one by one, and obtain the current signal I of the guide motor (10) corresponding to the diamond tool (6) at these positions during one cycle of the reciprocating swing of the rotary table (8). The value of the current signal I is positively correlated with the hardness of the circular arc blade of the diamond tool (6). When the diamond material removal rate and the grinding speed are unchanged, the characteristic signal value of the diamond tool (6) is: e=k1*f1*v / S In the formula, S represents the diamond material removal rate, f1 represents the grinding pressure, v represents the grinding speed, and k1 is the proportionality coefficient. The relationship between the output f2 of the guide motor (10) and the current signal I is f2=k2*I, where k2 is a proportionality coefficient, and the grinding pressure f1 and the output f2 of the guide motor (10) are regarded as the action force and the reaction force, so the characteristic signal value of the diamond tool (6) is: e=k1*k2*I*v / S The formula is dimensionless, where the proportional coefficients k1, k2 and the constant grinding speed v are multiplied together, and the product is the characteristic signal correction coefficient K. The characteristic signal value of the diamond tool (6) is: e=K*I / S The characteristics of each point on the circular arc edge of the diamond tool (6) are quantitatively represented by the current signal I of the guide motor (10), and the grinding pressure f1 and the grinding speed v are set according to the characteristic signal value e during the subsequent grinding process of the diamond tool (6); S6. Control the feed guide rail (9) to complete the tool retraction action and perform subsequent fine grinding of the diamond tool (6).

2. The method for identifying diamond tool features based on guide rail motor current signals according to claim 1, characterized in that: The radial rotation accuracy of the rotary table (8) is higher than 0.1 μm / 120°, the positioning accuracy of the feed guide rail (9) is higher than 0.1 μm / 100 mm, and the current feedback resolution of the guide rail motor (10) is higher than 1 mA.

3. The method for identifying diamond tool features based on guide rail motor current signals according to claim 1, characterized in that: In S5, the signal is divided into stages according to time intervals, and the time interval range is 1-10s.

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