JP2002144287A - Cutting method of resin workpiece and device for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a pattern from coming out onto a rear face of a worked sheet in half cutting, to improve the working efficiency by reducing the pressure force in cutting, and to improve the durability of a cutting blade. SOLUTION: A tool horn 6 is mounted on an ultrasonic vibrator 7, and a cutting blade 4 is fixed to the tool horn 6. A heating coil 5 is mounted around the cutting blade 4 while surrounding the same. Vacuum suction holes are formed on a lower face of a receiving pressure surface plate 1 to suck and hold the worked sheet 3. The supply of the current of high frequency to the heating coil 5 is started in a state that the worked sheet 3 is set on the receiving pressure surface plate 1, and the preparation for cutting work is completed as shown in a drawing (a), whereby a temperature of the cutting blade 4 is raised. A surface of the worked sheet 3 arrives at a tip part of the cutting blade 4 after a predetermined time from the start of the lowering of the receiving pressure surface plate 1 as shown in a drawing (b). The cutting is completed in a drawing (c).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cutting a resin workpiece such as a thermoplastic resin sheet.

[0002]

2. Description of the Related Art When cutting a resin workpiece, ultrasonic vibration is applied to a cutting blade or heated to improve the working efficiency. FIG. 9A is a cross-sectional view of a conventional cutting apparatus using ultrasonic vibration, and FIG. 9B is a cross-sectional view taken along line AA of FIG. 9A. As shown in FIG. 9, the work sheet 13 made of resin
Are arranged on the receiving pressure platen 11. Receiving pressure platen 11
A tool horn 16 having a cutting blade 14 fixed to the distal end thereof is installed opposite to. The tool horn 16 is fixed to an ultrasonic vibrator or a fixed horn fixed to the ultrasonic vibrator (both are not shown).

[0003] In cutting, the tool horn is lowered (or the receiving pressure plate is raised) and ultrasonic pressure is applied to the cutting blade 14 while applying pressure so that the cutting blade penetrates the sheet 13 to be processed. Alternatively, the cutting operation is terminated without causing the cutting blade to penetrate the work sheet, and processing in a so-called half-cut state is performed. A processing method of applying only ultrasonic vibration to the cutting blade or a processing method of using only the heating blade is described in, for example, JP-A-2000-95056 and JP-A-7-1567.
It is publicly known from Japanese Patent No. 39 and the like.

[0004]

In the above-described cutting method in which only ultrasonic vibration is applied to the cutting blade, since the cutting blade is at room temperature, a large pressing force is required and a sharp and thin cutting blade must be used. Is required. In addition, in this method, it is difficult to cut a workpiece without applying a large amplitude ultrasonic vibration to the cutting blade. Therefore, generally, an ultrasonic vibration having an amplitude of 30 μm or more is applied to the cutting blade. become. As a result, the following problems occur in the cutting method using only the ultrasonic vibration. The cutting blade is susceptible to stress rupture because the cutting blade with low mechanical strength must be used in addition to the large vibration amplitude being applied to the cutting blade. Further, the service life of the cutting blade is shortened. Since a large stress acts on the workpiece, a certain kind of undesired "telli" is generated on the back side of the cut surface (the front side as the product).

On the other hand, in the conventional method in which cutting is performed by simply heating the cutting blade, it is necessary to heat the cutting blade to a temperature 30 ° C. or more higher than the melting temperature of the workpiece material.
The following problems occur. The cutting part is apt to be drooped or deformed. When the molten resin adheres to the cutting blade and burns, a "smell" is generated, thereby deteriorating the working environment.
At the same time, the "sharpness" of the cutting blade also drops.

[0006] Therefore, the problem to be solved by the present invention is to solve the above-mentioned problems of the prior art. The object of the present invention is, firstly, to prevent the cutting blade from being damaged or reduced in sharpness. Second, it is necessary to prevent the appearance of an undesired pattern on the back surface of the cut surface when performing half-cutting, and to cause dripping or deformation in the cut portion. Is to be without.

[0007]

According to the present invention, in order to solve the above-mentioned problems, according to the present invention, while applying ultrasonic vibration to a cutting blade, the cutting blade is pushed into a resin workpiece to perform cutting. In the method of cutting a processed product, a method of cutting a resin processed product, which performs cutting while heating the tip portion of the cutting blade, is provided. Preferably, the tip of the cutting blade is heated, and the tip of the cutting blade is heated by an electromagnetic induction heating method.

According to another aspect of the present invention, there is provided a tool horn for transmitting vibration of an ultrasonic vibrator, a cutting blade attached to a tip of the tool horn, and a cutting blade. A heating device capable of heating rapidly, and a device for cutting a resin workpiece, provided.

[Operation] According to the cutting method of the present invention, in which ultrasonic vibration is applied to the cutting blade while heating it, the following operation and effects can be expected. Since the pressing force at the time of cutting can be reduced and the vibration amplitude of the cutting blade can be suppressed to 30 μm or less, breakage of the cutting blade can be prevented and the service life thereof can be prolonged. Set the heating temperature of the cutting blade to 1 from the melting temperature of the workpiece material.
The temperature can be kept low at about 0 to 20 ° C., and the adhesion of the molten resin can be prevented. It is possible to prevent an undesired pattern from appearing on the surface (back side of the cut surface) of the product, and to obtain a sharp cut surface.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a first embodiment of the present invention. FIG. 1A shows a state in which a preparation operation is completed, FIG. 1B shows a state immediately before a cutting operation is started, FIG. 1C shows a state when the cutting operation is completed. As shown in FIG. 1A, a tool horn 6 is fixed to an ultrasonic vibrator 7 which vibrates in a vertical direction, and a cutting blade 4 is attached to the tool horn 6.
Is fixed. A heating coil 5 is provided around the cutting blade 4 so as to surround it. The heating coil 5 is supported by a support member (not shown).
And it is moved so as not to disturb the cutting operation.
A cavity for flowing cooling water is opened inside the heating coil 5.

The receiving pressure platen 1 is supported by a pressure cylinder 2 which can move up and down. A vacuum suction hole is opened in the lower surface thereof so that the work sheet 3 can be sucked and held. I have. Further, when the processing of the sheet to be processed 3 is performed through the entire film thickness, an “escape groove” is formed in a portion where the cutting blade 4 of the receiving pressure platen 1 contacts. Note that a fixed horn may be interposed between the ultrasonic vibrator 7 and the tool horn 6. Here, since the cutting blade 4 is formed of a ferromagnetic material such as stainless steel, when a high-frequency current is supplied to the heating coil 5, heat is generated by electromagnetic induction heating. However, since the tool horn 6 is formed of a non-ferromagnetic material such as duralumin, the tool horn 6 hardly generates heat even when the heating coil 5 is energized.

FIG. 2 is a time chart showing the operation of the apparatus of the first embodiment. As shown in FIG. 1A, the work sheet 3 is set on the receiving pressure platen 1, and preparation for the cutting operation is completed. At time t1 (see FIG. 2),
The supply of the high-frequency current to the heating coil 5 is started, whereby the cutting blade 4 immediately starts generating heat and the temperature rises rapidly. At the same time, the pressure cylinder 2 starts lowering the receiving pressure platen 1. At time t2, as shown in FIG. 1B, the surface of the sheet 3 reaches the tip of the cutting blade 4. When the receiving pressure platen 1 is further lowered, cutting of the sheet to be processed is started. At the same time, the heating coil 5 starts to descend to avoid contact with the sheet 3 to be processed. Here, the time from t1 to t2, that is, the time from the start of heating to the start of cutting is set to about 0.1 to 1 second. It is difficult to heat the cutting blade to a sufficiently high temperature within 0.1 second, and the time is set to 1 second or less so as not to waste energy.

[0013] Since the ultrasonic vibration is applied to the cutting blade 4 and the cutting blade 4 is heated, the resistance received by the cutting blade from the sheet to be processed is low. In other words, the cutting proceeds smoothly due to the low pressing force. FIG. 3A is a diagram schematically showing the progress of cutting when only the ultrasonic vibration is applied and when the method of the present invention is applied.
In each case, the pressing force and the cutting time are kept constant. FIG. 3B shows a cross-sectional structure of the cutting blade 4. In a conventional example using only ultrasonic vibration, the thickness d of the cutting blade is 0.1 mm.
8 mm or less, an efficient cutting operation could not be performed unless the angle θ of the tip was 30 ° or less, but according to the present invention, the thickness d of the cutting blade was 0.8 mm or more, Even if the angle θ of the part is 30 ° or more, it is possible to perform a sufficiently efficient cutting operation. In addition, according to the present invention, since the vibration amplitude can be reduced, it is possible to prevent a breakage accident of the cutting blade and to dramatically improve the durability thereof. Further, according to the present invention, the cutting can be performed with a low pressing force, whereby the stress deformation of the workpiece can be reduced. Therefore, when the cutting is completed in the half-cut state, it is possible to obtain an effect that the cut pattern is not observed from the cut back surface side.

At time t3, the energization of the heating coil 5 is completed, and thereafter, the cutting operation is performed using the residual heat. At time t4, as shown in FIG. 1C, the cutting blade 4 penetrates the work sheet 3, and the cutting operation is completed. At this time, the heating coil 5 reaches the lowest point of its operation range. The receiving pressure platen 1 and the heating coil 5 start rising at time t5, and return to the initial state shown in FIG. 1A at time t6. In FIG. 1, the cutting blade is shown in a straight line, but its shape (planar shape as viewed from the cutting edge) can take any shape such as a circle, a rectangle, and a curve.

FIGS. 4A and 4B are cross-sectional views showing a second embodiment of the present invention. In FIG. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals,
Duplicate description will be omitted. This embodiment is different from the first embodiment in that the heating coil 5 can be moved not only in the vertical direction but also in the horizontal direction. When starting the cutting operation, first, as shown in FIG. 4A, the work sheet 3 is sucked and held by the receiving pressure platen 1. In this state, energization of the heating coil 5 is started to cause the cutting blade 4 to generate heat. When the temperature of the cutting blade 4 has risen sufficiently, the heating coil 5 is raised to a height exceeding the cutting blade 4, and then the power supply is terminated and the blade is moved in the horizontal direction (FIG. 4).
Move to the position shown in (b)].

Next, as shown in FIG. 4B, the receiving pressure platen 1 is lowered to cut the sheet 3 to be processed. The second embodiment may be modified as follows. That is, the heating coil 5 is arranged above the cutting blade 4, and the heating coil 5 performs only horizontal movement. With such a configuration, mechanical simplification can be achieved.

FIG. 5A is a sectional view showing a third embodiment of the present invention, and FIG. 5B is a time chart showing the operation thereof. In FIG. 5A, the same reference numerals are given to the same parts as those in FIG. 1, so that the overlapping description is omitted, but in the present embodiment, the heating coil 5 is incorporated. At the same time, a coil holder 8 capable of adsorbing and holding the sheet to be processed is fixed to the receiving pressure platen 1.

Next, a cutting method using the cutting apparatus of the third embodiment will be described with reference to FIG. From time t1, the receiving pressure platen 1 starts to descend from the state shown in FIG. 5A, and at time t2, the work sheet 3 comes into contact with the tip of the cutting blade 4, and the receiving pressure platen 1 Stops once. Then, energization of the heating coil 5 is started, and heating of the cutting blade 4 is started. At time t3, the cutting blade 4 is sufficiently heated and the energization to the coil is stopped. At the same time, the lowering of the receiving pressure platen 1 is restarted, and ultrasonic vibration is applied to the cutting blade. At time t4, the receiving pressure platen reaches the lowest point and the cutting is completed. At time t5, the receiving pressure platen 1 starts to rise and returns to the initial position at time t6. In the present embodiment, the application of the ultrasonic vibration is stopped at the time t5, but can be stopped at an appropriate time after the time t4.

FIG. 6A is a sectional view showing a fourth embodiment of the present invention, and FIG. 6B is a time chart showing the operation. In FIG. 6A, the same reference numerals are given to the same parts as those in FIG. 1, so that the overlapping description is omitted, but in this embodiment, the cutting blade 4 is fixed. The tool horn 6 is configured to move up and down together with the ultrasonic vibrator 7. The position of the receiving pressure platen 1 is fixed.

Next, the cutting operation of the fourth embodiment is shown in FIG.
This will be described with reference to FIG. In the state shown in FIG. 6A, energization of the heating coil 5 starts at time t1. At time t2 when the cutting blade 4 is sufficiently heated, the power supply to the heating coil is stopped, and at the same time, the lowering of the tool horn 6 is started (at this time, the position of the heating coil does not change). At time t3, the workpiece sheet 3 comes into contact with the cutting blade 4, and the application of ultrasonic vibration to the cutting blade 4 is started. The tool horn 6 continues descending at time t
At 4, the tool horn reaches the lowest point and cutting is complete. At time t5, the tool horn 6 starts to rise and at time t
At 6, return to the initial position. In the present embodiment, the application of the ultrasonic vibration is stopped at time t5, but at time t4.
Thereafter, it can be stopped at an appropriate time.

FIGS. 7 and 8 are cross-sectional views showing fifth and sixth embodiments of the present invention, respectively. In the first to fourth embodiments, the cutting blade is fixed to the tool horn, but in the fifth and sixth embodiments, the cutting blade is not fixed. In FIG. 7, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and overlapping descriptions will be omitted. In this embodiment, a non-woven fabric sheet 9 is stuck on the tool horn 6. Then, the cutting blade 4 is arranged on the nonwoven fabric sheet 9. The cutting operation on the sheet 3 to be processed in the present embodiment is the same as that in the first embodiment. In the apparatus of the present embodiment, the nonwoven fabric sheet 9 can transmit the ultrasonic vibration from the tool horn to the cutting blade 4 without greatly attenuating. On the other hand, noise (unpleasant treble) generated by the ultrasonic vibration can be greatly attenuated by the nonwoven fabric sheet. In addition, since the impact between the cutting blade and the tool horn is reduced, surface roughness of the tool horn can be prevented and the durability of the tool horn can be improved. Note that the nonwoven fabric sheet may be attached to the cutting blade side, or may be simply arranged without being attached.

In FIG. 8 showing the sixth embodiment, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and duplicate explanations will be omitted. In this embodiment,
A vacuum suction hole 10 is provided inside the tool horn 6, and is evacuated by a vacuum pump (not shown). The cutting blade 4 arranged on the vacuum suction hole 10 is vacuum-sucked on the tool horn 6. Cutting blade 4 shown in FIG.
In the configuration in which the woven sheet 3 is simply arranged, the misalignment is likely to occur, and the cutting blade and the sheet may not be separated smoothly when the woven sheet 3 is lifted. Thus, these disadvantages can be resolved.

While the preferred embodiment has been described above,
The present invention is not limited to these embodiments, but can be appropriately changed without changing the gist of the invention. For example, in the embodiment, the receiving surface of the receiving press platen is in the horizontal plane, but may be vertical. Further, in the embodiment, the receiving pressure platen and the tool horn move up and down, but both of them may be moved up and down. In the embodiment, the work sheet is held by the receiving pressure plate. However, instead of this configuration, an auxiliary plate is provided between the cutting blade and the receiving pressure plate to hold the work sheet. You may make it. In addition, it is possible to more efficiently heat the cutting blade by interposing a heat insulating material between the tool horn and the cutting blade. Further, the heating of the cutting blade can be performed by directly supplying a current to the cutting blade.

[0024]

As described above, according to the present invention, the cutting blade is heated only during the cutting operation while applying the ultrasonic vibration to the cutting blade, so that the following effects can be obtained. Since the cutting can be performed with a small pressing force, the deformation due to the stress during the half cutting can be suppressed to a small extent, and the appearance of the pattern by the cutting blade on the back surface can be suppressed. The same thickness can be cut in a shorter time as compared with the conventional method, and the working efficiency can be improved. By reducing the pressure and shortening the cutting time, the durability of the cutting blade can be improved. Even if the cutting blade is not thin and its tip is not sharp, cutting can be performed and the vibration amplitude of the cutting blade can be suppressed to a small degree, thereby preventing the breakage of the cutting blade. And its durability can be further improved. No dripping or deformation occurs in the cut portion of the workpiece, and a sharp cut surface can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a time chart showing the operation of the first embodiment of the present invention.

FIG. 3 is a sectional view for explaining the effect of the first embodiment of the present invention.

FIG. 4 is a sectional view showing a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of a third embodiment of the present invention and a time chart showing the operation thereof.

FIG. 6 is a cross-sectional view of a fourth embodiment of the present invention and a time chart illustrating the operation thereof.

FIG. 7 is a sectional view showing a fifth embodiment of the present invention.

FIG. 8 is a sectional view showing a sixth embodiment of the present invention.

FIG. 9 is a sectional view of a conventional example.

[Explanation of symbols]

 1, 11 Receiving press platen 2 Press cylinder 3, 13 Worksheet 4, 14 Cutting blade 5 Heating coil 6, 16 Tool horn 7 Ultrasonic vibrator 8 Coil holder 9 Nonwoven fabric sheet 10 Vacuum suction hole

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Johhiro Ota 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Co., Ltd. (72) Inventor Junichi Kumaki 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F term (reference) 3C021 EA05 EA09 3C060 AA04 CA03 CF02 CF13

Claims (23)

[Claims] 1. A method for cutting a resin workpiece, wherein the cutting blade is pushed into a resin workpiece while applying ultrasonic vibration to the cutting blade, and the cutting is performed while heating the tip of the cutting blade. A method for cutting a resin workpiece. 2. The method according to claim 1, wherein the cutting blade cuts the resin workpiece to an intermediate depth and terminates the cutting operation. 3. The method for cutting a resin workpiece according to claim 1, wherein the vibration direction of the ultrasonic vibration is parallel to a cutting surface formed on the workpiece. 4. The cutting work of the resin workpiece is started within 0.1 to 5 seconds after the heating of the tip of the cutting blade is started. The method for cutting a resin workpiece according to any one of the above. 5. The heating of the tip of the cutting blade is completed simultaneously with or earlier than the completion of the cutting work of the resin workpiece by the cutting blade.
5. The method for cutting a resin workpiece according to any one of items 1 to 4. 6. The method for cutting a resin workpiece according to claim 1, wherein the cutting blade itself serves as a heating element to heat the tip of the cutting blade. 7. The method for cutting a resin workpiece according to claim 1, wherein the tip of the cutting blade is heated by an electromagnetic induction heating method. 8. The cutting blade according to claim 1, wherein the ultrasonic vibration of the tool horn is transmitted to the cutting blade through an interposer.
7. The method for cutting a resin workpiece according to any one of items 7 to 7. 9. The method for cutting a resin workpiece according to claim 8, wherein the interposer is made of a nonwoven fabric. 10. The ultrasonic vibration amplitude of said cutting blade is 30.
The method for cutting a resin workpiece according to any one of claims 1 to 9, wherein the thickness is not more than μm. 11. The method for cutting a resin workpiece according to claim 1, wherein a heating temperature of the cutting blade during a cutting operation is equal to or lower than a melting temperature of the resin workpiece. . 12. A tool horn for transmitting vibration of an ultrasonic vibrator, a cutting blade driven by the tool horn to perform ultrasonic vibration, and heating means capable of rapidly heating the cutting blade. An apparatus for cutting a resin workpiece, comprising: 13. The resin processing apparatus according to claim 12, wherein said heating means has a coil disposed around said cutting blade, and a power supply for supplying a high-frequency current to said coil. Cutting equipment. 14. The apparatus according to claim 13, wherein the coil is supported by a support independent of the tool horn. 15. The apparatus according to claim 1, wherein the coil is movable in a direction parallel or vertical to the vibration direction of the ultrasonic vibration of the tool horn, or in the parallel and vertical directions. 15. The apparatus for cutting a resin workpiece according to 13 or 14. 16. The resin processing machine according to claim 12, wherein the cutting blade is formed of a ferromagnetic material, and the tool horn is formed of a non-ferromagnetic material. Cutting equipment. 17. The apparatus for cutting a resin workpiece according to claim 12, wherein said heating means is a means for directly supplying an electric current to said cutting blade. 18. The tool according to claim 12, wherein the cutting blade is fixed to a tip of the tool horn.
The cutting device for a resin workpiece according to any one of the above. 19. The apparatus for cutting a resin workpiece according to claim 12, wherein the cutting blade is supported without being fixed to the tool horn. 20. The apparatus according to claim 19, wherein the cutting blade is supported by the tool horn by vacuum suction means. 21. The resin workpiece according to claim 12, wherein ultrasonic vibration energy is supplied to the cutting blade from the tool horn via an interposer. Cutting device. 22. The apparatus for cutting a resin workpiece according to claim 12, wherein the thickness of the cutting blade is 0.8 mm or more. 23. An angle θ between two surfaces of a tip portion of the cutting blade is 30 ° or more.
23. The apparatus for cutting a resin workpiece according to any one of claims to 22.