JP2008178926A - Cutting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that although it is necessary to prevent thermal deformation of a tool due to heat generated during cutting operation in addition to improve driving accuracy of a cutting machine when performing highly accurate machining in cutting, the highly accurate cutting cannot be done because part of the heat generated on a cutting chip is conducted to a shank and causes the tool to deform. <P>SOLUTION: A cutting device is used, which includes a tool shank to which the cutting chip is mounted, a temperature sensor for measuring the temperature of the shank and outputting its temperature information, a calculator for inputting the temperature information output from the temperature sensor and outputting a control signal for lowering the temperature when the temperature rises compared with a desired temperature of the shank and for raising the temperature to put the shank at the desired temperature when the temperature lowers, and a temperature conditioner for inputting the control signal output from the calculator to adjust the temperature of the tool shank at its desired temperature. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cutting apparatus that performs high-precision processing using a cutting tool.

  There are cases where sub-micron precision processing is required for components of electronic equipment and optical equipment such as infrared lenses using germanium (hereinafter referred to as Ge) and silicon (hereinafter referred to as Si). In that case, cutting using a precision machine tool is used.

  In precise cutting, the movement trajectory of the cutting tip that is the cutting edge of the cutting tool must be controlled with high accuracy and processed into a desired shape. For this purpose, not only the drive accuracy of the processing machine is improved, but also the heat generated during the process, for example, frictional heat due to cutting, and thermal deformation of the machine or tool due to heat generated by driving the motor / spindle, etc. are suppressed. There is a need.

  Therefore, as a method for suppressing the processing heat from the tool blade edge among the generated heat, conventionally, a cutting fluid such as water or oil, or a gas such as air, nitrogen or carbon dioxide is injected into the cutting tool blade edge in the cutting process. (See, for example, Patent Document 1).

  As another method for cooling the cutting edge, a method of cooling the tip of a cutting tool using a fluid passage or a Peltier element for temperature adjustment is shown (for example, see Patent Document 2).

Japanese Patent Laid-Open No. 2-95540 (pages 1 and 2, FIG. 1) JP-A-2005-279860 (pages 3-7, FIGS. 1-9)

  In order to realize high-precision machining as described above, it is necessary to remove machining heat generated between the tool and the workpiece and suppress deformation due to heat conduction to the tool shank. However, even if the cutting fluid is used, only the vicinity of the machining point can be cooled, so that heat cannot be completely removed, and part of the heat may be transferred to the tool shank to cause deformation.

  Further, even if the cutting tip is cooled by using a fluid passage for temperature adjustment or a Peltier element, the generated heat cannot be completely removed, and part of the heat is transferred to the tool shank. As a result, the tool shank expands and deforms, causing deterioration in machining accuracy. On the other hand, when the cooling is excessive, the temperature of the tool shank is lowered and the tool shank is contracted, which may degrade the processing accuracy.

  The present invention has been made in order to solve the above-described problems, and even when heat generated during machining is transmitted to the tool shank, the movement trajectory of the tool blade edge is not affected, thereby cutting the workpiece. The purpose is to perform high-precision machining in submicron units.

The cutting device according to the present invention includes:
A tool shank for attaching a cutting tip for cutting a workpiece;
A temperature sensor that measures the temperature of the tool shank and outputs temperature information of the tool shank;
The temperature information output from the temperature sensor is input, and when the temperature is increased with respect to a desired temperature of the tool shank, the temperature is decreased, and when the temperature is decreased, the temperature is increased and the temperature is increased. A computer that outputs a control signal such that the tool shank has a desired temperature;
A temperature adjuster that inputs the control signal output from the calculator and adjusts the temperature of the tool shank to a desired temperature;
It is provided with.

  According to the present invention, when a part of the heat at the cutting tip is transmitted to the tool shank, the tool shank can be kept at a predetermined temperature because it is removed by the temperature adjuster. Therefore, the deformation of the tool shank due to the processing heat can be prevented, and the workpiece can be cut to perform high precision processing in submicron units.

Embodiment 1 FIG.
FIG. 1 shows a block diagram of a cutting apparatus according to Embodiment 1 of the present invention. The tool shank 2 is attached to the tool moving table 1 in the cutting apparatus. Further, a cutting tip 3 is fixed to the tip of the tool shank 2. The workpiece is processed by the cutting tip 3 by moving the tool moving table 1. FIG. 1 shows a state in which a workpiece is being processed by the cutting tip 3, 4 a is a pre-processed surface that is a state before processing on the workpiece, and 4 b is a processing that is a state after processing on the workpiece. Shows the surface.

  A temperature sensor 5 for measuring the temperature of the tool shank 2 is attached to the tool shank 2. The temperature sensor 5 measures the temperature of the tool shank 2 and outputs temperature information 6. The temperature information 6 output from the temperature sensor 5 is input to the computer 7. The computer 7 reduces the temperature when the temperature rises with respect to the desired temperature of the tool shank 2 by the temperature adjuster 8 attached to the tool shank 2, and raises the temperature when the temperature falls, so that the temperature of the tool shank 2 is increased. Is given a control signal 9 so that the temperature becomes a desired temperature.

  For example, the computer 7 compares the input temperature information 6 with a desired temperature in the tool shank 2 given in advance, and sends a control signal 9 for temperature rise or temperature drop to the temperature adjuster 8 according to the temperature difference. The temperature of the tool shank 2 is set to a desired temperature. The temperature adjuster 8 receives the control signal 9 from the computer 7 and adjusts the temperature of the tool shank 2 to a desired temperature.

  Thereby, when a part of the heat is transferred to the tool shank 2, the heat transferred to the tool shank 2 is removed by the temperature adjuster 8, so that the temperature of the tool shank 2 can be set to a desired temperature and the deformation of the tool can be suppressed. . Even when the tool shank 2 is overcooled, the temperature of the tool shank 2 can be raised by the temperature adjuster 8 so as to compensate for the cooling, and the temperature of the tool shank 2 can be set to a desired temperature. Therefore, tool deformation can be suppressed, and the workpiece can be cut to perform high-precision machining in submicron units.

  In the first embodiment, the calculator 7 may be included in the tool moving table 1. Examples of the workpiece include an infrared lens of Ge or Si, iron, and aluminum, but the workpiece is not limited to these. The material of the tool shank 2 includes, for example, iron, but the material of the tool shank 2 is not limited to this. In addition, examples of the material of the cutting tip 3 include diamond, but the material of the cutting tip 3 is not limited to this.

  As the temperature adjuster 8, for example, a Peltier element or the like can be considered. In this case, the Peltier element control signal output from the computer 7 is used to cool the heat generated during processing using the Peltier element. However, the temperature adjuster 8 need not be a Peltier element as long as the temperature can be adjusted, and the type thereof is not limited.

Embodiment 2. FIG.
FIG. 2 shows a block diagram of a cutting apparatus according to Embodiment 2 of the present invention. In FIG. 2, the configuration operation from the tool shank 2 to the temperature sensor 5 is the same as that in the first embodiment, and thus the description thereof is omitted.

  FIG. 3 is a graph showing the amount of thermal expansion of the tool shank 2 with respect to temperature change when iron is used as the material of the tool shank 2. Data processing corresponding to the graph of FIG. 3 is executed by, for example, the computer 7 in FIG. The horizontal axis of FIG. 3 shows the change temperature (° C.) with respect to the desired temperature of the tool shank 2, and the vertical axis shows the thermal expansion amount of the tool shank 2, that is, the shank expansion amount (μm) with respect to the change temperature. The thermal expansion amount of the tool shank 2 is the thermal expansion amount in the Z-axis direction in FIG.

  When the length of the tool shank 2 is represented by L (m), the coefficient of thermal expansion is represented by α (/ ° C.), and the change temperature is represented by ΔT (° C.), the amount of thermal expansion ΔL (m) of the tool shank 2 is represented by the following equation. Is done.

図３では、工具シャンク２の長さＬを３０（ｍｍ）、鉄の熱膨張率αを１２×１０^−６（／℃）とした場合の、変化温度ΔＴ（℃）に対する熱膨張量ΔＬ（μｍ）を示している。

In FIG. 3, when the length L of the tool shank 2 is 30 (mm) and the thermal expansion coefficient α of iron is 12 × 10 ⁻⁶ (/ ° C.), the thermal expansion amount ΔL (with respect to the change temperature ΔT (° C.) μm).

  The computer 7 in FIG. 2 calculates the thermal expansion amount of the tool shank 2 based on the temperature information 6 output from the temperature sensor 5 according to the graph shown in FIG. For example, the change temperature of the tool shank 2 is obtained based on the temperature information 6 input to the computer 7. When the material of the tool shank 2 is iron, the thermal expansion amount of the tool shank 2 with respect to the change temperature is known according to FIG. 3, so the conversion table of the change temperature and the thermal expansion amount is provided in the computer 7, and the change temperature is calculated. It may be converted into a thermal expansion amount and output. The thermal expansion amount calculated by the computer 7 is output as a correction signal 10 to the tool movement adjustment unit 11 provided inside the tool movement table 1.

  The tool movement adjusting unit 11 moves the tool moving table 1 or the tool shank 2 itself in the Z-axis direction of FIG. 2 based on the input correction signal 10 and cancels the thermal expansion amount of the tool shank 2.

  Thereby, even when a part of heat is transmitted to the tool shank 2, the thermal expansion amount of the tool shank 2 can be corrected. Even when the tool shank 2 is overcooled, the shrinkage amount of the tool shank obtained from the amount of cooling can be corrected in the same manner as in the case of thermal expansion. Therefore, it is possible to correct the displacement of the cutting tip 3 attached to the tool shank 2 due to thermal fluctuation, and it is possible to cut the workpiece and perform high precision machining in submicron units.

  In the second embodiment, since the thermal expansion amount, which is the displacement amount of the tool shank 2, is obtained and corrected based on the temperature information 6, the tool shank 2 is responsive to the response of the temperature adjuster 8 compared to the first embodiment. Further high-precision control can be performed without the difficulty of control such that the temperature of the liquid is too high or too low.

  In the second embodiment, the tool moving table 1 and the tool shank 2 itself are moved to correct the amount of thermal expansion of the tool shank 2, but a movement adjusting unit is provided on the spindle for fixing the workpiece. Alternatively, the correction signal 10 output from the computer 7 may be input to correct the spindle position with respect to the Z-axis direction shown in FIG.

Embodiment 3 FIG.
FIG. 4 shows a block diagram of a cutting apparatus according to Embodiment 3 of the present invention. In FIG. 4, the configuration operation from the tool shank 2 to the temperature sensor 5 is the same as that of the first embodiment, and thus the description thereof is omitted.

  The temperature information 6 output from the temperature sensor 5 is input to the computer 7. The calculator 7 reduces the temperature of the tool shank 2 when the temperature rises, and raises the temperature when the temperature is lowered with respect to the desired temperature of the tool shank 2 by the temperature adjuster 8 attached to the tool shank 2. A control signal 9 is given so that the temperature becomes a desired temperature. The operations up to the above are the same as in the first embodiment.

  In addition, the computer 7 has a function of judging the life of the cutting tip 3 by monitoring the amount of change of the input temperature information 6 per unit time or the amount of change of the output control signal 9 per unit time.

  For example, the computer 7 includes a life determination unit 12. The life determination unit 12 has a function of outputting the control signal 9 to the temperature adjuster 8 based on the temperature information 6 as described above. In addition, the life determination unit 12 has a function of taking out the temperature information 6 or the control signal 9 at regular time intervals and calculating the amount of change per unit time.

  When the cutting tip 3 is worn, the tip of the cutting tip 3 is rounded. As a result, the processed surface 4b obtained by cutting the workpiece becomes rough, and the desired shape accuracy cannot be maintained, and at the same time, the processing heat easily accumulates on the cutting tip 3.

  Then, the temperature rise of the cutting tip 3 becomes large. Since processing heat is transferred from the cutting tip 3 to the tool shank 2, the temperature rise of the tool shank 2 is increased, and the temperature change amount per unit time of the tool shank 2 is also steep. Further, since the temperature change amount per unit time of the tool shank 2 becomes steep, the change amount per unit time of the control signal 9 also increases.

  In the life determination unit 12, a threshold is set for the amount of change per unit time of the input temperature information 6 or the amount of change per unit time of the control signal 9 to be output. When the amount of change per unit time of the temperature information 6 or the amount of change per unit time of the control signal 9 exceeds a predetermined threshold, it is determined that the cutting tip 3 is at the end of its life. The life determination unit 12 that has determined that the cutting tip 3 has a life outputs a stop signal 13 to the tool moving base 1. When the stop signal 13 is input, the tool driving unit 14 of the tool moving table 1 moves the cutting tip 3, that is, the tool moving table 1 away from the workpiece, and stops the operation of the tool including the tool moving table 1 and the like. .

  If the life determination unit 12 determines that the cutting tip 3 is not at the end of its life, the life determination unit 12 outputs a control signal 9 to the temperature regulator 8 based on the temperature information 6 as in the first embodiment. To do.

  Thereby, the effect similar to Embodiment 1 can be acquired. In addition, it has a function of determining the life of the cutting tip 3 during processing. Therefore, it is possible to avoid a case where a desired processing accuracy cannot be obtained by processing the workpiece using the cutting tip 3 that has reached the end of life, or a case where the workpiece is accidentally damaged.

  In the third embodiment, the life determination unit 12 determines the life of the cutting tip 3 based on the change amount of the temperature information 6 per unit time or the change amount of the control signal 9 per unit time. However, if the threshold value is determined with respect to the temperature information 6 itself or the control signal 9 itself instead of the amount of change, and the temperature information 6 or the control signal 9 exceeds a predetermined threshold value, the life determination unit 12 indicates that the cutting tip 3 is at the end of its life. Therefore, the tool moving table 1 may be stopped by determining that the temperature has suddenly increased and outputting the stop signal 13 to the tool driving unit 14 of the tool moving table 1.

Embodiment 4 FIG.
FIG. 5 shows a block diagram of a cutting apparatus according to Embodiment 4 of the present invention. In FIG. 5, the configuration operation from the tool shank 2 to the temperature sensor 5 is the same as that in the second embodiment, and thus the description thereof is omitted.

  The temperature information 6 output from the temperature sensor 5 is input to the computer 7. Similarly to the second embodiment, the calculator 7 calculates the thermal expansion amount of the tool shank 2 based on the temperature information 6 output from the temperature sensor 5 according to the graph shown in FIG. Output. The operations up to the above are the same as in the second embodiment.

  In addition, the calculator 7 has a function of judging the life of the cutting tip 3 by monitoring the amount of change of the input temperature information 6 per unit time or the amount of change of the correction signal 10 to be output per unit time.

  For example, the computer 7 includes a life determination unit 12. As described above, the life determination unit 12 has a function of outputting the correction signal 10 to the tool movement adjustment unit 11 based on the temperature information 6. In addition, the life determination unit 12 has a function of taking out the temperature information 6 or the correction signal 10 at regular time intervals and calculating the amount of change per unit time.

  When the cutting tip 3 is worn, the tip of the cutting tip 3 is rounded. As a result, the processed surface 4b obtained by cutting the workpiece becomes rough, and the desired shape accuracy cannot be maintained, and at the same time, the processing heat easily accumulates on the cutting tip 3.

  Then, the temperature rise of the cutting tip 3 becomes large. Since processing heat is transferred from the cutting tip 3 to the tool shank 2, the temperature rise of the tool shank 2 is increased, and the temperature change amount per unit time of the tool shank 2 is also steep. Further, since the temperature change amount per unit time of the tool shank 2 becomes steep, the change amount per unit time of the correction signal 10 also increases.

  In the life determination unit 12, a threshold is set for the amount of change per unit time of the input temperature information 6 or the amount of change per unit time of the correction signal 10 to be output. When the amount of change per unit time of the temperature information 6 or the amount of change per unit time of the correction signal 10 exceeds a predetermined threshold, it is determined that the cutting tip 3 has a lifetime. The life determination unit 12 that has determined that the cutting tip 3 has a life outputs a stop signal 13 to the tool moving base 1. When the stop signal 13 is input, the tool driving unit 14 of the tool moving table 1 moves the cutting tip 3, that is, the tool moving table 1 away from the workpiece, and stops the operation of the tool including the tool moving table 1 and the like. .

  If the life determination unit 12 determines that the cutting tip 3 is not a life, the life determination unit 12 sends a correction signal 10 to the tool movement adjustment unit 11 based on the temperature information 6 as in the second embodiment. Output.

  Thereby, the same effect as Embodiment 2 can be acquired. In addition, it has a function of determining the life of the cutting tip 3 during processing. Therefore, it is possible to avoid a case where a desired processing accuracy cannot be obtained by processing the workpiece using the cutting tip 3 that has reached the end of life, or a case where the workpiece is accidentally damaged.

  In the fourth embodiment, the life determination unit 12 determines the life of the cutting tip 3 based on the change amount of the temperature information 6 per unit time or the change amount of the correction signal 10 per unit time. However, when the threshold value is determined for the temperature information 6 itself or the correction signal 10 itself that is the thermal expansion amount instead of the change amount, and the temperature information 6 or the correction signal 10 exceeds a predetermined threshold value, the life determination unit 12 determines the cutting tip. The tool moving table 1 may be stopped by determining that the temperature has suddenly increased since 3 is a life and outputting a stop signal 13 to the tool driving unit 14 of the tool moving table 1.

Embodiment 5. FIG.
FIG. 6 shows a cutting apparatus according to Embodiment 5 of the present invention. A heat insulating material 15 is inserted between the tool shank 2 and the cutting tip 3 so that heat generated during processing stays in the cutting tip 3 and is not transmitted to the tool shank 2.

  Thereby, it is possible to suppress the heat generated during the process from being transmitted to the tool shank 2 simply by inserting the heat insulating material 15, and the tool shank 2 can be easily installed without the temperature sensor 5, the calculator 7, and the temperature adjuster 8. Deformation can be suppressed.

  In addition, as a material of the heat insulating material 15, a multi-hard ceramic etc. are mentioned, for example. However, as long as the heat insulating material 15 can insulate the heat transmitted from the cutting tip 3 to the tool shank 2, the kind thereof is not limited.

  Moreover, the deformation | transformation of the tool shank 2 can further be suppressed by using together the heat insulating material 15 in the above-mentioned Embodiment 5 with respect to Embodiment 1 to Embodiment 4.

Embodiment 6 FIG.
FIG. 7 shows a cutting apparatus according to Embodiment 6 of the present invention. By attaching the cooling fin 16 to the cutting tip 3, the processing heat of the cutting tip 3 is dissipated into the air and removed.

  Accordingly, the deformation of the tool shank 2 can be easily suppressed without the temperature sensor 5, the computer 7, the temperature adjuster 8, and the like.

  In addition, as a material of the cooling fin 16, aluminum etc. are mentioned, for example. However, the type of the cooling fin 16 is not limited as long as the processing heat of the cutting tip 3 can be removed.

  Further, by inserting a heat insulating material 15 between the tool shank 2 and the cutting tip 3 and using the heat insulating material 15 and the cooling fin 16 together, it is possible to prevent heat generated during processing from being transferred from the cutting tip 3 to the tool shank 2. Good. By using the heat insulating material 15 and the cooling fins 16 in combination, it is possible to further suppress tool deformation due to heat generated during processing transmitted to the tool shank 2.

  Moreover, it is possible to further prevent heat from being transmitted to the tool shank 2 by using the cooling fins 16 in the above-described sixth embodiment together with the first to fourth embodiments. In that case, you may use the heat insulating material 15 together as mentioned above.

1 is a block diagram of a cutting apparatus according to Embodiment 1 of the present invention. The block diagram of the cutting apparatus in Embodiment 2 of this invention is shown. It is the graph which showed the thermal expansion amount of the tool shank 2 with respect to the temperature change at the time of using iron for the material of the tool shank 2. The block diagram of the cutting apparatus in Embodiment 3 of this invention is shown. The block diagram of the cutting apparatus in Embodiment 4 of this invention is shown. 10 shows a cutting apparatus according to Embodiment 5 of the present invention. It shows the cutting apparatus in Embodiment 6 of this invention.

Explanation of symbols

1. Tool moving table2. Tool shank 3. Cutting tip 4a. Pre-processed surface 4b. 4. Processed surface 5. Temperature sensor Temperature information7. Calculator 8 Temperature controller 9. Control signal 10. Correction signal 11. Tool movement adjusting unit 12. Life determination unit 13. Stop signal 14. Tool drive unit 15. Insulation 16. Cooling fins

Claims (9)

A tool shank for attaching a cutting tip for cutting a workpiece;
A temperature sensor that measures the temperature of the tool shank and outputs temperature information of the tool shank;
The temperature information output from the temperature sensor is input, and when the temperature is increased with respect to a desired temperature of the tool shank, the temperature is decreased, and when the temperature is decreased, the temperature is increased and the temperature is increased. A computer that outputs a control signal such that the tool shank has a desired temperature;
A temperature adjuster that inputs the control signal output from the calculator and adjusts the temperature of the tool shank to a desired temperature;
A cutting apparatus characterized by comprising: The calculator includes a life determination unit,
The life determination unit obtains a change amount per unit time of the temperature information or the control signal, and stops cutting when the change amount per unit time is larger than a predetermined threshold value, and is smaller than the predetermined threshold value. 2. The cutting apparatus according to claim 1, wherein the control signal is output to the temperature adjuster so that the tool shank has a desired temperature. The calculator includes a life determination unit,
The life determination unit stops cutting when the temperature information or the control signal is greater than a predetermined threshold value, and when the temperature information or the control signal is smaller than the predetermined threshold value, the tool shank has a desired temperature at the temperature adjuster. The cutting apparatus according to claim 1, wherein the control signal is output. A tool shank for attaching a cutting tip for cutting a workpiece;
A temperature sensor that measures the temperature of the tool shank and outputs temperature information of the tool shank;
The temperature information output from the temperature sensor is input, the thermal expansion amount of the tool shank corresponding to the difference between the desired temperature of the tool shank and the temperature information is obtained, and a signal corresponding to the thermal expansion amount is output. A calculator to
A tool movement that inputs a signal corresponding to the thermal expansion amount output from the calculator, moves the cutting tip in the thermal expansion direction of the tool shank, and corrects the amount of displacement of the cutting tip due to thermal expansion. An adjustment unit;
A cutting apparatus characterized by comprising: The calculator includes a life determination unit,
The life determination unit obtains a change amount per unit time of the temperature information or the thermal expansion amount, and when the change amount per unit time is larger than a predetermined threshold, the cutting is stopped, and from the predetermined threshold The cutting apparatus according to claim 4, wherein if it is smaller, a signal corresponding to the thermal expansion amount is output to the tool movement adjusting unit, and the amount of displacement of the cutting tip due to thermal expansion is corrected. The calculator includes a life determination unit,
The life determination unit stops cutting when the temperature information or the thermal expansion amount is larger than a predetermined threshold value, and when the temperature information or the thermal expansion amount is smaller than the predetermined threshold value, the tool movement adjustment unit sends a signal corresponding to the thermal expansion amount. The cutting device according to claim 4, wherein the amount of displacement of the cutting tip due to thermal expansion is corrected.   The cutting apparatus according to claim 1, wherein a heat insulating material is attached between the cutting tip and the tool shank.   The cutting apparatus according to claim 1, wherein a cooling fin that releases heat generated in the cutting tip is attached to the cutting tip.   9. The cutting apparatus according to claim 1, wherein the workpiece is an infrared lens.

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