JPH10328886A - Holding device for working thin sheet and its holding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep flatness and tension constant under an optimal working condition without giving an elastic deformation to a thin sheet and moreover without generating strain. SOLUTION: This holding device is provided with clamping mechanisms 30A, 30B respectively clamping both end parts of the sheet 10 with the load of a compressing spring 36 via rubber plates 34, the tension providing mechanism 40 pulling one side of the clamping mechanism in the direction widening the sheet with an air cylinder 42, and the supporting mechanism 50 including the lower part support 52 for supporting the working part of the widened sheet from the lower side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holding apparatus and a holding method for processing a thin sheet, and more particularly, to a sheet thickness of 0.4 mm.
Flatness and tension under optimal processing conditions so as not to apply elastic deformation to the thin sheet and to prevent distortion from occurring, which is suitable for use when performing fine processing with laser light on the entire surface of a thin metal sheet of a degree or less. The present invention relates to a holding device for processing a thin sheet and a holding method for holding the thin sheet on the holding device for processing, which can keep the thickness constant.

[0002]

2. Description of the Related Art When performing fine processing by laser light on the entire surface of a thin metal sheet, the flatness of the metal sheet is required. That is, when laser processing such as cutting is performed on a thin metal sheet, the laser beam focused through a lens or the like is on the metal sheet. When the positional relationship between the condensed beam and the metal sheet changes, processing quality such as cutting width and cutting shape accuracy is affected. Also, when the metal sheet is moved in accordance with the movement of the processing position, it is necessary to always hold the metal sheet so as not to fluctuate in the height direction or the like. Therefore, conventionally, as illustrated in FIG. 7, both ends of the metal sheet 10 are clamped by clamp mechanisms 12A and 12B including a clamp lever 14 and a fixing screw 16 for mechanically sandwiching and holding the sheet, respectively, and the sheet is pulled. The metal sheet 10 is held flat by pulling the clamp mechanism 12B on the side with a screw mechanism 20 having a screw handle 22 for pulling the sheet.

[0003]

However, if the metal sheet 10 is strongly pulled by the screw feed mechanism 20 in order to increase the flatness of the metal sheet 10, the metal sheet 10 is elastically deformed and stretched, resulting in a defective product. Become.
In addition, even if elastic deformation is not caused, when tension is applied by the screw feed mechanism 20, the entire metal sheet 10 is elongated, and it is necessary to correct the amount of elongation in terms of processing accuracy. Furthermore, every time the metal sheet 10 is set, it is necessary to apply tension by the screw feed mechanism 20, which not only complicates the operation but also makes it difficult to set an appropriate tension every time. there were.

[0004] In particular, when the metal sheet is pulled from four directions, it is difficult to stretch the metal sheet uniformly without causing waving or wrinkling, and the difference in displacement between the center and the end of the metal sheet is kept within a certain range. There was also a problem that it was difficult to control.

On the other hand, instead of pulling the metal sheet, a method of mechanically pressing the metal sheet from above and below can be considered. In this case, for example, when the processed portion of the metal sheet is supported like a table from below, the height of the processed portion is kept constant even if the entire metal sheet is bent, and the problem of elongation of the metal sheet is caused. Does not occur.

However, since the metal sheet bends differently at the center and at the end of the metal sheet, the fluctuation of the height position is large, for example, 100 μm or more when viewed over the entire area. If the laser beam focused through a lens or the like is applied to the metal sheet to melt it and blow it out with the assist gas ejection pressure to form a hole, the center of the nozzle from which the assist gas is ejected is processed. Since the pressure due to the assist gas is also applied to the portion, the position change is likely to occur. If the metal sheet is mechanically pressed from the top to prevent this position change, not only will the metal surface be damaged, but also the position change due to the assist gas pressure will not be sufficiently eliminated. I was

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and is intended to keep the flatness and the tension constant under optimum processing conditions so as not to give an elastic deformation and generate a distortion. A first object is to provide a possible holding device for processing thin sheets.

A second object of the present invention is to provide a holding method for holding a thin sheet by the holding apparatus for processing a thin sheet.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a working holding device for holding a thin sheet in an expanded state during working, wherein both ends of the sheet are clamped by spring loads via respective elastic pressing members. At least one pair of clamp means, at least one of the clamp means,
The first object has been solved by providing tension applying means for pulling a sheet in a direction in which the sheet is spread by fluid pressure, and support means including a lower support for supporting a processed portion of the spread sheet from below. is there.

Further, at least one of a spring load of the clamp means, a fluid pressure of the tension applying means, and a height of the lower support can be adjusted.

[0011] The support means may further include an upper support nozzle disposed above the lower support with the sheet interposed therebetween and for blowing gas for pressing the sheet against the lower support.

Further, there is provided unclamping means for overcoming the load of the spring and releasing the sheet from the elastic pressing member.

According to the present invention, there is also provided a similar holding apparatus for processing a thin sheet, wherein a lower support for supporting a processing portion of the spread sheet from below is provided, and the lower support is disposed above the lower support with the sheet interposed therebetween. The first object is achieved by providing a support means including an upper support nozzle for blowing gas for pressing the sheet against the lower support.

According to the present invention, when the thin sheet is held by the processing holding device, first, both ends of the sheet are clamped by the spring of the clamp means, and then the sheet is pressed by the fluid pressure of the tension applying means. After pulling in the direction of spreading, the lower support of the support means is raised to hold the sheet at a predetermined position, thereby solving the second problem.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

According to the first embodiment of the present invention, as shown in FIG. 1, a rubber plate having a coefficient of friction in a range of, for example, 0.3 to 0.8 for clamping both ends of a metal sheet 10 is provided. A clamp plate 32 provided on a contact surface with the metal sheet 10 and movable in the direction of arrow A; a compression spring 36 for urging the clamp plate 32 in a direction to press the metal sheet 10; A pair of clamp mechanisms 30 including a load adjusting screw 38 for adjusting the load of the pair 36
A, 30B and a sheet pulling side clamping mechanism 30B
As shown by the arrow B in the direction in which the metal sheet 10 is spread.
0, a lower support 52 that can be raised and lowered, as shown by an arrow C, for supporting the processed portion of the spread sheet from below, and a lower support 52 with the metal sheet 10 interposed therebetween. And a support mechanism 50 including an upper support nozzle 56 for blowing gas for pressing the metal sheet 10 against the surface of the lower support 52.

The load of the compression spring 36 pressing the clamp plate 32 can be adjusted by a load adjusting screw 38.

The tension of the metal sheet 10 can be adjusted by the air pressure applied to the air cylinder 42 of the tension applying mechanism 40. The means for pulling the metal sheet at a predetermined tension is not limited to an air cylinder.

The height of the lower support 52 can also be adjusted.

The upper support nozzle 56 is provided with a processing head 60 for performing laser processing as shown in FIG.
It is integrated with. The processing head 60 includes a lens 64 for converging a processing laser beam 62 and a processing nozzle 66 provided at a tip (lower end in the figure) of the processing head 60.
An assist gas flow path 68 for supplying an assist gas (for example, oxygen) for blowing away the metal sheet 10 melted by the laser inside the processing nozzle 66;
A support gas flow path for supplying a support gas (for example, compressed air) for pressing the metal sheet 10 against the lower support 52 on the lower surface of the metal sheet 10, and the support gas is blown onto the surface of the metal sheet 10 from the lower surface of the processing head 60. And the upper support nozzle 56.

As shown in detail in FIG. 3, a large number of support gas outlets 72 of the support nozzle 56 are provided around the processing nozzle 66 in a circumferential shape.

The lower support 5 immediately below the processing nozzle 66
An assist gas suction port 54 is formed on the second side as shown in FIG.

In FIG. 2, reference numeral 74 denotes a pressure gauge.

When holding the metal sheet 10,
First, both ends of the metal sheet 10 are clamped via the rubber plate 34 of the clamp plate 32.

Next, a tension in the range of, for example, 15 to 30 kg is applied to the metal sheet 10 and pulled by the air cylinder 42 of the tension applying mechanism 40.

When tension is applied by the air cylinder 42 in this manner, a certain degree of flatness can be ensured. However, in order to further ensure the flatness, the lower support 52 is raised and lightly pressed against the lower surface of the metal sheet 10. Then, the processed portion of the metal sheet 10 is held at a predetermined height. The height of the lower support 52 can be adjusted within a range of 2 mm below to 2 mm above, for example, with respect to the clamp reference of the lower surface of the metal sheet.

When the processing position does not move, the support by the lower support 52 alone is stable, but when the processing position is changed, the height of the metal sheet may fluctuate. Therefore, the distance G between the upper support nozzle 56 and the surface of the metal sheet 10 is a predetermined value (for example, 50 to 50).
Then, compressed air having a constant pressure P (for example, 0.5 to 4 kg) is blown from the support gas outlet 72 to the surface of the metal sheet 10. The metal sheet is pressed against the surface of the lower support 52 by this support gas, so that even if the processing position is changed at a high speed, the height variation of the metal sheet surface is kept within, for example, 50 μm.

In this way, after the initial setting, the optimum conditions can be repeatedly and automatically set.
A thin metal sheet of 4 mm or less, under the same conditions each time,
It can be held without wrinkles and with minimal elongation.

In the present embodiment, the support by the clamp mechanism, the tension applying mechanism and the lower support 52 is used together with the support by the compressed air blown from the upper support nozzle 56. In addition, the variation in the height position of the metal sheet can be suppressed to, for example, 50 μm in the entire region.

It is also possible to omit the blowing of the support gas by the upper support nozzle or to use only the support mechanism by the lower support and the upper support nozzle.

The types of the assist gas and the support gas blown from the upper support nozzle 56 are not limited to oxygen and compressed air. The elastic pressing member for pressing the sheet is not limited to the rubber plate.

In this embodiment, since only one clamp mechanism 30B is pulled by the tension applying mechanism 40, the configuration is simple. Note that a tension applying mechanism is also provided in the other clamp mechanism 30A, and the metal sheet 1
0 may be pulled from both sides.

Next, a second embodiment of the present invention will be described in detail with reference to FIGS.

In the second embodiment, the same clamping mechanisms 30A and 30B as in the first embodiment
The clamp width can be adjusted by mounting the mounts 80A, 80B on the mounts 80A, 80B movable upward in the direction of arrow D and fixing the mounts 80A, 80B with the fixing handle 84 according to the width of the metal sheet 10. At the same time, the unclamping mechanism 86 for releasing the clamp by pulling up the clamp plate 32 of each clamping mechanism against the compression spring 36.
Is provided.

At the time of clamping, as shown in FIG. 6, the clamping mechanisms 30A and 30B are
Thus, the metal sheet 10 is fixed to the same width, and the end 30E of the clamping mechanism is made flush with the height at which the metal sheet 10 is clamped.

Next, the unclamping mechanism 86 is operated by, for example, an air cylinder (not shown) to
The metal sheet 10 is inserted from the lateral direction of the clamp mechanism (for example, the operation side in FIG. 5) in a state where the clamp plate 32 is lifted upward by overcoming the above load, and set at a predetermined position.

Thereafter, unclamping by the unclamping mechanism 80 (clamping of the metal sheet 10 by the compression spring 36) → pulling the clamp mechanism 30B by the air cylinder 42 of the tension applying mechanism 40 to apply a constant tension to the metal sheet 10 → Processing of metal sheet 10 by processing head 60 (completion) → Release of tension application by tension application mechanism 40 → Series of unclamping operation by unclamping mechanism 80
Work can be done automatically. After the unclamping, the metal sheet 10 is taken out.

Therefore, if the insertion and removal of the thin metal sheet from the lateral direction are automatically performed using an automatic supply / discharge device or the like, the automatic operation can be continuously performed without the intervention of an operator. Become.

In this embodiment, the air cylinder is used for the tension applying mechanism and the unclamping mechanism. However, the method of applying the tension and the driving method of the unclamping mechanism are as follows.
It is not limited to the one using an air cylinder.

In each of the above embodiments, the present invention is applied to a metal sheet, but the present invention is not limited to metal.

[0041]

According to the present invention, under the optimum processing conditions, the thin sheet is not elastically deformed and is not distorted.
Flatness and tension can be kept constant.

In particular, when the upper support nozzle is used, even if the processed portion of the sheet moves at a high speed, it is possible to suppress a change in the height position of the processed portion on the sheet surface.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a first embodiment of a metal sheet processing holding device according to the present invention.

FIG. 2 is a longitudinal sectional view showing a processing head according to the first embodiment.

FIG. 3 is a bottom view showing the shape of the upper support nozzle.

FIG. 4 is a top view showing the shape of the lower support.

FIG. 5 is a plan view showing a second embodiment of the present invention.

FIG. 6 is a perspective view of the same main part.

FIG. 7 is a cross-sectional view showing the configuration of an example of a conventional holding apparatus for processing a thin sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Metal sheet 30A, 30B ... Clamp mechanism 32 ... Clamp plate 34 ... Rubber plate 36 ... Compression spring 38 ... Load adjustment screw 40 ... Tension applying mechanism 42 ... Air cylinder 50 ... Support mechanism 52 ... Lower support 56 ... Upper support nozzle 60 ... Processing head 62 ... Laser beam 66 ... Processing nozzle 68 ... Assist gas flow path 72 ... Support gas outlet 86 ... Unclamp mechanism

Claims (6)

[Claims] 1. A processing holding device for holding a thin sheet in an expanded state at the time of processing, wherein at least one pair of clamping means for clamping both ends of the sheet by a spring load via respective elastic pressing members. A tension applying means for pulling at least one of the clamping means in a direction in which the sheet is expanded by fluid pressure, and a support means including a lower support for supporting a processed portion of the expanded sheet from below. Characteristic holding device for processing thin sheets. 2. The processing of a thin sheet according to claim 1, wherein at least one of a spring load of said clamping means, a fluid pressure of said tension applying means, and a height of said lower support are adjustable. For holding device. 3. The apparatus according to claim 1, wherein said support means comprises:
The holding apparatus for processing a thin sheet further includes an upper support nozzle which is disposed above the lower support with the sheet interposed therebetween and blows gas for pressing the sheet against the lower support. 4. A holding apparatus for processing a thin sheet according to claim 1, further comprising unclamping means for overcoming the load of said spring and releasing said sheet from said elastic pressing member. . 5. A processing holding device for holding a thin sheet in an expanded state during processing, comprising: a lower support for supporting a processed portion of the expanded sheet from below; An upper support nozzle which is disposed above and blows gas for pressing the sheet against the lower support, and a support means comprising: a support device for processing a thin sheet. 6. When holding a thin sheet with the holding device for processing according to any one of claims 1 to 4, first, both ends of the sheet are clamped by a spring of the clamping means, and then the tension applying means is provided. A method for holding a thin sheet, wherein the sheet is pulled in a direction in which the sheet is spread by the fluid pressure, and the lower support of the support means is raised to hold the sheet at a predetermined position.