JPH0788672A - Method and device for machining metal sheet and method for machining lead frame - Google Patents

Abstract

PURPOSE:To surely converge laser beam on a metal sheet and finely, precisely machine even in machining with laser beam while gushing assist gas in a time of machining the metal sheet. CONSTITUTION:In a time of machining a metal sheet 101 with irradiating pulse like laser beam 100 while gushing high pressure assist gas from a nozzle 2, high pressure liquid is spouted in the reverse direction against the assist gas gushing direction from a liquid gushing unit 6 installed on the back surface of the metal sheet 101. In such a way, the metal sheet 101 is held at a position that the push down force of the assist gas is balanced to the push up force of the high pressure liquid. Further, sealing fluid is fed so as to encircle the assist gas from a sealing gas gushing opening 10 installed on the front surface side of the metal sheet 101, and the balance of pressures between the front and back surfaces of the metal sheet 101 is corrected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal plate processing method and apparatus for irradiating a metal plate with a laser beam and ejecting an assist gas coaxially with the laser beam, and a metal plate processing apparatus. The present invention relates to a used lead frame processing method.

[0002]

2. Description of the Related Art Laser beam processing locally and instantaneously melts a metal plate, which is a work piece. Therefore, it is possible to process finer dimensions with higher dimensional accuracy than conventional pressing or etching. can do. In order to perform fine and high-precision processing on a metal plate with this laser beam processing method, it is essential to focus the laser beam finely with a condenser lens. In particular, the laser beam is focused on the metal plate. It is indispensable to make the light converge so that the focal point, that is, the focal position, does not shift. If the focus position shifts, fine and highly accurate machining may not be possible, or the machining itself may become impossible.

When processing is performed by the laser beam as described above, a relatively narrow area near the portion where the metal plate is to be processed is supported, and the metal plate is fed while being processed.
As a conventional method for supporting a metal plate to be processed, there is a method called the Kenzan method as described in Japanese Patent Laid-Open No. 4-284995. In this method, a metal plate to be processed is supported by at least three columnar supporting members, and a laser beam is applied to this.

[0004]

When processing is performed with a laser beam, the assist gas is usually jetted coaxially with the laser beam to be output. The ejection of the assist gas is performed to assist the combustion of the processed portion of the metal plate by laser beam irradiation, or to blow off and remove the generated molten material to suppress the formation of dross. When a thin metal plate such as a lead frame or a metal mask is supported by the Kenzan method or the like for laser beam processing, the metal plate is irradiated with the laser beam under the pressure of the assist gas ejected as described above. It bends as it is pushed downward from the surface (hereinafter called the surface). As a result, the focal position of the laser beam does not exist on the metal plate, and it is not possible to perform fine and highly accurate processing,
In some cases, the processing itself becomes impossible. Therefore, conventionally, it has been necessary to perform processing while correcting the bending deformation of the metal plate due to the assist gas.

In order to avoid the bending of the metal plate as described above, it is conceivable that the metal plate is supported by a support base having a certain size instead of the Kenzan system. But in this case,
Dross caused by the melt remaining without being completely removed by the assist gas and scattered spatter etc. were projected on the surface of the metal plate opposite to the surface irradiated with the laser beam (hereinafter referred to as the back surface). Since they adhere to each other in a state, they cannot be securely attached to the support base, and it becomes impossible to feed the metal plate while performing the processing. Therefore, it is necessary to remove these dross and spatter every time the processing of a certain area is completed, set again, and then perform the next processing, which is very troublesome.

Further, rather than supporting a relatively narrow portion of the metal plate as in the case of the Kenzan system or the system of supporting with a support table having a certain size as described above, the metal plate is not fed. If the dross sticks out on the back surface of the metal plate, it will not hinder the processing if it is processed with supporting a wide enough area, but in this case, the degree of sagging of the metal plate by the assist gas increases, and High-precision machining cannot be performed.

It is an object of the present invention to reliably focus a laser beam on a metal plate even when performing processing with a laser beam while ejecting an assist gas, so that fine and highly accurate processing can be performed. (EN) Provided are a metal plate processing method and a processing device, and a lead frame processing method using the metal plate processing device.

[0008]

To achieve the above object, according to the present invention, a metal plate is processed by irradiating a metal plate with a pulsed laser beam while ejecting a high-pressure assist gas from a nozzle. In the method for processing a metal plate, a high-pressure liquid is ejected from a surface of the metal plate opposite to a surface irradiated with the laser beam in a direction opposite to the ejection direction of the assist gas to support the metal plate. A method for processing a metal plate is provided.

In the above method for processing a metal plate, preferably, a surface of the metal plate irradiated with the laser beam is
A shield fluid having a pressure lower than the pressure of the assist gas is supplied so as to surround the assist gas.

To achieve the above object, according to the present invention, a metal plate is processed by irradiating a metal plate with a pulsed laser beam while ejecting a high-pressure assist gas from a nozzle. In the apparatus, a high-pressure liquid is ejected on the surface of the metal plate opposite to the surface irradiated with the laser beam in a direction opposite to the ejection direction of the assist gas, and the metal plate is supported via the liquid. An apparatus for processing a metal plate is provided, which has liquid supporting means for

In the above metal plate processing apparatus, preferably, a surface of the metal plate irradiated with the laser beam is
It further has a shield fluid supply means for supplying a shield fluid having a pressure lower than the pressure of the assist gas so as to surround the assist gas.

Further, it is preferable that the nozzle and the liquid ejecting means are coaxial and integrally formed.

Preferably, the liquid jetting means comprises:
Detecting means for detecting the distance between the liquid ejecting means and the metal plate is provided.

Further, preferably, there is provided a flow rate control means for controlling the flow rate of the liquid ejected from the liquid ejection means, or a pressure control means for controlling the pressure of the liquid ejected from the liquid ejection means.

Further, preferably, a through hole is provided at the center of the liquid jetting means.

Further, preferably, a ring-shaped member for receiving the liquid ejected from the liquid ejecting means is mounted coaxially with the nozzle on the surface of the metal plate irradiated with the laser beam.

Further, in order to achieve the above object, according to the present invention, there is provided a lead frame processing method characterized in that a lead frame is processed by a metal plate processing apparatus.

[0018]

When performing processing with a laser beam, the metal plate is pushed downward from the surface by the pressure of the high-pressure assist gas ejected from the nozzle together with the laser beam as described above. On the other hand, in the metal plate processing method of the present invention configured as described above, high pressure is applied to the surface of the metal plate opposite to the surface irradiated with the laser beam, that is, from the back surface in the direction opposite to the ejection direction of the assist gas. By ejecting the liquid of (3), a force opposite to the pressure of the assist gas in the direction of pushing up from the back surface is applied to the metal plate. As a result, the vertical position of the metal plate is maintained at a position where the pushing-down force by the assist gas and the pushing-up force by the high-pressure liquid are just balanced.

Further, since the assist gas is a gas, it has a low viscosity, and the pressure of the ejected assist gas sharply decreases as the distance from the nozzle ejecting the assist gas increases.
On the other hand, since the liquid ejected from the back surface of the metal plate has a high viscosity, the degree of pressure drop is smaller than that of the assist gas, and the pressure can be stably maintained over a wide range to some extent. Based on such a difference in properties between the two, even if the pressure of the assist gas slightly changes, the pressure of the liquid ejected from the back surface of the metal plate hardly changes, and the liquid causes a slight change in the pressure of the assist gas. It is possible to prevent the metal plate from being absorbed and to be bent, and to stably maintain its shape.

From the above, the distance between the tip of the nozzle and the metal plate can be kept substantially constant, and the laser beam can be reliably focused on the metal plate. That is, since the focus position of the laser beam does not shift during processing, fine processing can always be performed under good focusing conditions. Further, since the metal plate is prevented from being bent and deformed, it is possible to reduce the dimensional error. In particular, the present invention is effective in processing a thin metal plate that is easily deformed by the pressure of the assist gas. Furthermore, it is possible to remove the melt, spatter, dust, generated gas, etc., which is the source of dross, by mixing them with the liquid.

Further, as described above, the pressure of the assist gas sharply drops with distance from the nozzle and is unstable,
It is difficult to keep the balance with the liquid ejected from the back surface of the metal plate. In the present invention, by supplying the shield fluid so as to surround the assist gas on the surface of the metal plate, the instability of the pressure of the assist gas as described above is eliminated and the pressure balance between the front surface and the back surface of the metal plate is balanced. It is possible to correct. In this case, the reason why the shield fluid is ejected is to eliminate the instability of the pressure of the assist gas, so the pressure is set to a pressure lower than the pressure of the assist gas.

In the metal plate processing apparatus of the present invention, since the liquid jetting means is provided on the back surface of the metal plate,
The high-pressure liquid can be jetted in the direction opposite to the jetting direction of the assist gas, and the metal plate processing method of the present invention can be carried out. Further, since the metal plate is supported by the liquid ejecting means through the liquid, the dross or spatter due to laser beam irradiation does not directly contact the liquid ejecting means, and the metal plate is supported smoothly and surely. Supporting accuracy is also good. Therefore, it becomes possible to stably and easily feed the metal plate at high speed and low speed while performing the processing.

Further, since the nozzle and the liquid jetting means are coaxial and have an integral structure, it is possible to draw the same locus in one piece when performing machining on any locus, and always use the assist gas. It is possible to exactly balance the pushing down force and the pushing up force by the high-pressure liquid.

Further, by providing a through hole at the center of the liquid ejecting means, it is possible to wash away melts, spatters, dust, generated gas, etc. accompanying the processing together with the liquid from the through hole, and clean the liquid ejecting means. Can be kept. As a result, the piping of the liquid ejecting means will not be clogged, and maintenance and inspection will be facilitated. Further, since the processing can be performed without hindering the assist gas from penetrating the metal plate and flowing to the back surface, it is possible to sufficiently exert the function of the assist gas of blowing out the generated melt and suppressing the formation of dross.

Further, by providing the liquid ejecting means with the detecting means, the distance between the liquid ejecting means and the metal plate can be detected by the detecting means, and the distance can be controlled to be constant. As a result, the pressure of the liquid can be kept constant, and the distance between the nozzle tip and the metal plate can be kept constant. Further, the flow rate or pressure of the liquid ejected from the liquid ejecting means may be directly controlled.

By mounting a ring-shaped member coaxially with the nozzle on the surface of the metal plate, the liquid ejected from the liquid ejection means to the surface side through the ejection processing portion can be received by the ring-shaped member. As a result, it is possible to prevent the liquid that has flowed out to the surface side through the processed portion from scattering, and the liquid received by this ring-shaped member has the same action as the shield fluid described above, and the surface of the metal plate It becomes possible to correct the pressure balance on the back side and the back side.

Since the processing apparatus as described above can perform fine and highly precise processing on a thin metal plate, it is difficult to perform fine and highly accurate processing by conventional etching or pressing. It is suitable for forming a lead frame having a size and shape from a metal plate.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method and apparatus for processing a metal plate according to the present invention will be described with reference to FIGS.

FIG. 1 is a view showing a metal plate processing apparatus according to this embodiment, and is an enlarged sectional view of a lower portion of a processing head and a lower cover. In FIG. 1A, a nozzle 2 is provided below a processing head 1 so as to face a metal plate 101 to be processed.
Laser beam 10 is attached to the upper part of the nozzle 2.
A condenser lens 3 for condensing 0 is attached, and a protective glass 4 for protecting the inside of the processing head 1 is attached below the condenser lens 3. An assist gas supply port 5 is provided below the nozzle 2, and the assist gas supplied from the assist gas supply port 5 is supplied to the nozzle 2 as indicated by an arrow 301 in the figure.
It is ejected from the tip portion 2A.

On the surface of the metal plate 101 opposite to the surface on which the laser beam 100 is irradiated, that is, the back surface, the liquid ejector 6 is arranged so as to face the nozzle 2 and to be aligned with the center position. ing. This liquid ejector 6 has a lower cover 7
The lower cover 7 is supplied with a high-pressure liquid from the liquid supply port 8, and the metal plate 1 is supported through the liquid filled therein. Further, a gap sensor 9 which is a detecting means is attached to the lower cover 7, and the distance between the lower cover 7 and the metal plate 1 is detected. A plan view of the liquid ejector 6 is shown in FIG. However, FIG.
It is a BB sectional view of (a).

The liquid ejected from the liquid ejector 6 may be fresh water, but a liquid having a large viscosity in which silicates or phosphates are dissolved in fresh water is preferable. Such a liquid has a large viscosity, and also has an effect of protecting the metal plate 101 by forming a protective film on the surface of the metal plate 101.

A shield fluid ejection port 10 is provided on the outer periphery of the tip portion 2A of the nozzle 2, and the shield gas supplied from the shield fluid supply port 11 is indicated by an arrow 302 in the figure. Nozzle 2 as shown
Is ejected so as to surround the assist gas ejected from the front end portion 2A. However, instead of ejecting the shield gas from the shield fluid ejection port 10 as described above, the shield liquid may be ejected.

A laser beam 100 enters from a laser oscillator (not shown) to the condenser lens 3 in the processing head 1, and the laser beam condensed by the condenser lens 3 is the metal plate 1.
It is irradiated so as to focus on 01. As a result, the metal plate 101 is locally and instantaneously melted to form a processing portion (notch portion) 101a. In this state, the processing head 1 is moved relative to the metal plate 101 to perform processing. proceed. At this time, the assist gas is simultaneously ejected from the nozzle 2 coaxially with the laser beam 100 applied to the metal plate 101. The ejection of the assist gas is performed to assist the combustion of the processed portion of the metal plate 101 due to the irradiation of the laser beam 100, or to blow off and remove the generated melted material to suppress the formation of dross. The laser oscillator, the processing head, and the like have the same configurations as those conventionally known.

By the way, when a thin metal plate is supported by the Kenzan method or the like and laser beam processing is performed by the conventional method, the metal plate 101 receives the pressure of the assist gas.
At this time, the pressure of the assist gas is highest near the center of the nozzle 200 and becomes lower toward the periphery of the nozzle 200. Therefore, as shown in FIG. 2, the vicinity of the center of the nozzle 200 is pushed downward from the surface. Deflection. As a result, the focal position of the laser beam 100 does not exist on the metal plate 101, so that fine and highly accurate processing cannot be performed, and the processing itself may be impossible. Therefore, conventionally, it is necessary to perform the processing while correcting the flexural deformation of the metal plate 101 due to the assist gas.

On the other hand, in this embodiment, the metal plate 101
From the liquid ejector 6 provided on the back surface of the
Since a high-pressure liquid is jetted in the direction opposite to the jet direction of the assist gas as shown by, the metal plate 101 is given a force opposite to the pressure of the assist gas and pushed upward from the back surface. As a result, the vertical position of the metal plate 101 is maintained at a position where the pushing-down force by the assist gas and the pushing-up force by the high-pressure liquid are just balanced.

Further, since the assist gas is a gas, it has a low viscosity, and the pressure of the ejected assist gas sharply decreases as the distance from the nozzle ejecting the assist gas increases.
On the other hand, since the liquid ejected from the back surface of the metal plate has a high viscosity, the degree of pressure drop is smaller than that of the assist gas, and the pressure can be stably maintained over a wide range to some extent. Due to such a difference in properties between the two, even if the pressure of the assist gas slightly changes, the liquid ejector 6
Further, the pressure of the ejected liquid hardly changes, the liquid absorbs a subtle change in the pressure of the assist gas, the bending of the metal plate 101 is avoided, and the shape can be stably maintained.

Further, since the metal plate 101 is supported by the liquid ejector 6 through the liquid, the dross and spatter caused by the irradiation of the laser beam 100 hardly directly contact the liquid ejector 6, and the metal plate 101 is It is supported smoothly and surely, and its supporting accuracy is also good. Therefore, the metal plate 101 can be easily fed while performing the processing. Furthermore, it is possible to remove the melt, spatter, dust, generated gas, etc., which is the source of dross, by mixing them with the liquid.

Further, as described above, the pressure of the assist gas sharply decreases with distance from the nozzle, and is unstable,
It is difficult to maintain balance with the liquid ejected from the liquid ejector 6. On the other hand, in the present embodiment, the shield fluid ejection port 10 is provided on the outer periphery of the tip end portion 2A of the nozzle 2, and the shield fluid is supplied so as to surround the assist gas on the surface of the metal plate 101. It is possible to eliminate the instability of the pressure of the assist gas and correct the pressure balance between the front surface and the back surface of the metal plate 101. in this case,
The reason for ejecting the shield fluid is to eliminate the instability of the pressure of the assist gas, so the pressure is set to a pressure lower than the pressure of the assist gas.

The liquid ejected between the lower cover 7 and the metal plate 101 flows down from the outer peripheral portion of the lower cover 7.

Next, the supply system of the assist gas, the shield gas, and the liquid in the metal plate processing apparatus according to this embodiment will be described with reference to FIG. In FIG. 3, the high-pressure assist gas is supplied from the gas source 21 to the assist gas supply port 5 by opening the valve 22. The pressure at this time is indicated by the pressure gauge 23. Also, the shield gas is valve 32.
Shield fluid supply port 1 from gas source 31 by opening
1 is supplied. The pressure of this shield gas is the pressure reducing valve 33.
Is reduced to a pressure lower than the assist gas. The pressure at this time is indicated by the pressure gauge 34.

Further, the metal plate 101 is fed and positioned by the feeding roll 102 in the direction of arrow 103 in the figure. The feeding roll 102 also has a function of moving the laser beam irradiation position of the metal plate 101 in the X-axis direction. Further, although not shown in FIG. 3, a Y-axis moving base for moving the processing head 1 and the liquid ejector 6 at the same time is provided (see FIG. 4). However, the X axis and the Y axis are the metal plate 101.
Axes that are orthogonal to each other set on the surface of.

The liquid 40 is stored in the tank 41,
It is sent to the filter 43 through the pipe line 42. Dust, metal powder, etc. in the liquid are removed by the filter 43, and the liquid that has passed through the filter 43 is pumped by a pump 45 driven by a motor 44. The pressure of the liquid from the pump 45 is controlled by the pressure reducing valve 46, the flow rate is controlled by the flow rate control valve 47, and the liquid is supplied from the pipe line 48 to the liquid supply port 8 of the liquid ejector 6.
A pressure gauge 49 is attached on the downstream side of the flow control valve 47, and the pressure gauge 49 indicates the pressure of the liquid supplied to the liquid ejector 6. In addition, the valves 50 and 51 are connected to the pipeline 4.
Open and close 8.

The gap sensor 9 detects the distance between the lower cover 7 and the metal plate 1 as described above, and a signal based on the detection result is sent to the supply system controller 60.
The supply system control unit 60 includes a detection unit 61, a main control unit 62, and a liquid control unit 63. A signal based on the detection result of the gap sensor 9 is input to the detection unit 61, and the main control is performed based on the signal. In the section 62, the rotation speed of the motor 44 that drives the pump 45, the set value of the urging force of the pressure reducing valve 46, and the set value of the flow rate of the flow rate control valve 47 are calculated. , Pressure reducing valve 4
6. The flow rate control valve 47 is controlled.

As a result, the pressure and flow rate of the liquid sent to the liquid ejector 6 are controlled, and the force with which the lower cover 7 pushes the metal plate 101 upward through the liquid is controlled. Therefore, the distance between the lower cover 7 and the metal plate 101 can be controlled to be substantially constant, and the distance between the nozzle 2 and the metal plate 101 can be controlled to be substantially constant. The distance between the nozzle 2 and the metal plate 101 is determined by photographing the processing portion with a CCD camera during laser processing and determining the suitability based on the image information, or by determining the suitability based on the appearance and the processing quality after processing. It may be corrected from the time of the next processing.

From the above, the laser beam can be reliably focused on the metal plate 101. That is, since the focus position of the laser beam does not shift during processing, fine processing can always be performed under good focusing conditions. Further, since the metal plate 101 is prevented from being bent and deformed, the dimensional error can be reduced. It should be noted that instead of controlling both the pressure and the flow rate of the liquid sent to the liquid ejector 6, only one of them may be controlled.

Further, as shown in FIG. 4, the processing head 1 provided with the nozzle 2 is supported by the support arm 201, and the liquid ejector 6 is attached to the stand 202.
1 and the stand 202 are fixed to the fixing portion 203. At this time, the processing head 1 and the liquid ejector 6 are fixed so as to be coaxially arranged. The fixed portion 203 is attached to a movable portion 205 that moves on the Z-axis moving base 204 in the Z-axis direction. Further, the Z-axis moving base 204 is the Y-axis moving base 20.
6 is attached to a movable part 207 that moves in the Y-axis direction. However, the Z axis is an axis orthogonal to both the X axis and the Y axis, the movable portion 205 is moved by a motor 208 via a ball screw (not shown), and the movable portion 207 is moved by a motor 209 via a ball screw (not shown). Moving.

In the above structure, the processing head 1
Since the liquid ejector 6 and the liquid ejector 6 are fixed to the fixed portion 203, the positions of the both in the Z-axis direction can be integrally adjusted by moving the movable portion 205 without changing their relative positions, and the movable portion 207. By moving the metal plate 1
01 can be moved in the Y-axis direction. Further, since the processing head 1 and the liquid ejecting device 6 are coaxially fixed to each other, the both can be integrally moved in the X-axis direction on the metal plate 101 by the feeding roll 102 (see FIG. 3). it can. That is, the nozzle 2 and the liquid ejector 6 can be moved coaxially and integrally so as to draw the same locus, and even when machining is performed on any locus, the pressing force by the assist gas and the high-pressure liquid are always maintained. It can be exactly balanced with the pushing force by.

According to the present embodiment as described above, the metal plate 1
Since the high-pressure liquid is ejected from the liquid ejector 6 provided on the back surface of 01 in the direction opposite to the ejection direction of the assist gas, the vertical position of the metal plate 101 is maintained, and the metal plate 101 is bent and deformed. Is prevented. Further, based on the detection result of the gap sensor 9, the motor 44, the pressure reducing valve 4
6. Since the flow rate control valve 47 is controlled to control the pressure and flow rate of the liquid sent to the liquid ejector 6, the distance between the lower cover 7 and the metal plate 101 can be controlled to be substantially constant, and the nozzle 2 and The distance of the metal plate 101 can be controlled to be substantially constant. As a result, the laser beam can be reliably focused on the metal plate 101, and fine processing can always be performed under good focusing conditions. Also, the metal plate 1
Since 01 is prevented from being bent and deformed, dimensional error can be reduced.

Further, since the metal plate 101 is supported by the liquid ejector 6 through the liquid, the dross and spatter caused by the irradiation of the laser beam 100 do not directly contact the liquid ejector 6, and the metal plate 101 is smooth. In addition, it is reliably supported, and its supporting accuracy is also good. Therefore, the metal plate 101 can be stably and easily fed at high speed and low speed while performing the processing. Furthermore, it is possible to remove the melt, spatter, dust, generated gas, etc., which is the source of dross, by mixing them with the liquid.

Further, since the shield fluid jet port 10 is provided on the outer periphery of the tip portion 2A of the nozzle 2 and the shield fluid is supplied so as to surround the assist gas on the surface of the metal plate 101, the front surface and the back surface of the metal plate 101. The pressure balance of can be corrected.

Further, since the machining head 1 and the liquid ejector 6 are coaxially fixed to each other and have an integral structure, the nozzle 2 and the liquid ejector 6 are coaxial and integrally draw the same locus. Therefore, the pressing force by the assist gas and the pushing force by the high-pressure liquid can be exactly balanced at all times, regardless of the trajectory.

Further, the metal plate 101 is not bent and deformed, and the metal plate 101 is smoothly and surely supported by the liquid ejector 6 without being affected by dross or spatter, and its supporting accuracy is also good. A wide area can be processed at one time, and the processing efficiency is extremely good.

Next, another embodiment of the method and apparatus for processing a metal plate according to the present invention will be described with reference to FIG. In this embodiment, only the structure of the liquid ejector is different, and the other structures are the same as those in the above-mentioned embodiments. In FIG. 5, the same members as those in FIG. 1 are designated by the same reference numerals. As shown in FIGS. 5A and 5B,
The lower cover 7a of the liquid ejector 6a has a closed shape instead of the open shape like the lower cover 7 of FIG. 1, and a large number of holes 7b are provided on the upper surface of the lower cover 7a. However, FIG. 5B is a sectional view taken along line BB of FIG. Then, the high-pressure liquid supplied from the liquid supply port 8a is stored in the lower cover 7a and ejected from the hole 7b as indicated by an arrow 303 in the figure. With such a configuration, it is possible to prevent the melt, spatter, dust, and the like from entering the liquid inside the lower cover 7a.

A through hole 7c is formed in the center of the lower cover 7b.
Is provided. The liquid ejected between the lower cover 7a and the metal plate 101 flows down not only from the outer peripheral portion of the lower cover 7a but also from the through hole 7c and is collected. By providing the through hole 7c at the center of the lower cover 7a in this way, it is possible to wash away melts, spatters, dust, generated gas, etc. accompanying the processing from the through hole 7c together with the liquid.
Therefore, also by this, it is possible to prevent the melt, spatter, dust, and the like from mixing with the liquid in the lower cover 7a, and the piping of the liquid ejector 7a is not clogged.
Easy maintenance and inspection. In addition, the assist gas is the metal plate 1.
Since the processing can be performed without obstructing the flow through 01 to the back surface, the function of the assist gas of blowing off the generated melt can be sufficiently exerted.

As described above, according to this embodiment, the same effect as that of the above-described embodiment can be obtained, and the hole 7b of the lower cover 7a can be obtained.
Since the liquid is ejected more, it is possible to prevent dust and the like from mixing with the liquid in the lower cover 7a. Also, the lower cover 7b
Since the through hole 7c is provided in the center of the above, it is possible to avoid that the melted material, spatter, dust, generated gas, etc. accompanying the processing are washed away from the through hole 7c together with the liquid and mixed into the liquid in the lower cover 7a. Therefore, maintenance and inspection of the liquid ejector 7a becomes easy. Further, since processing can be performed without hindering the assist gas from penetrating the metal plate 101 and flowing to the back surface,
The function of the assist gas can be fully exerted.

Next, still another embodiment of the metal plate processing method and apparatus according to the present invention will be described with reference to FIG. In this embodiment, there is no structure for ejecting the shield gas, and instead a ring-shaped member is provided around the nozzle, and other structures are the same as those of the embodiment of FIG. In FIG. 6, the same members as those in FIG. 5 are designated by the same reference numerals. As shown in FIG. 6, the outer periphery of the tip portion 2b of the nozzle 2a is not provided with the shield fluid ejection port 10 as shown in FIGS. 1 and 5, but instead, a ring-shaped member 2c is mounted coaxially with the nozzle 2a. . The ring-shaped member 2c has a shape like a cover that covers the tip 2b of the nozzle 2a.

By the way, as the processing by the laser beam progresses, the processed portion 101 formed on the metal plate 101.
a is gradually increased, and the liquid ejected from the liquid ejector 6a flows out to the machining head 1 side through the machining section 101a. The liquid that has flowed out to the side of the processing head 1 is received by the ring-shaped member 2c as indicated by the arrow 304 in the figure, and is stored in the space 2d surrounded by the ring-shaped member 2c, and the excess liquid is indicated by the arrow 305 in the figure. It is collected together with the liquid flowing out from the outer periphery of the ring-shaped member 2c and flowing out from the liquid ejector 6a. Thus, by mounting the ring-shaped member 2c coaxially with the nozzle 2a, it is possible to prevent the liquid that has come out to the front surface side from scattering. In addition, the liquid received by the ring-shaped member 2c exhibits the same action as the shield fluid described in FIG. 1, and the surface of the metal plate 101 does not require the configuration for supplying the shield fluid shown in FIGS. It becomes possible to correct the pressure balance on the back side and the back side.

As described above, according to this embodiment, the same effect as that of the embodiment of FIG. 5 can be obtained, and further, it is possible to prevent the liquid that has flowed out to the surface side through the processed portion 101a from scattering. Figure 1
It is possible to correct the pressure balance between the front surface and the back surface of the metal plate 101 without requiring the configuration for supplying the shield fluid shown in FIG.

Next, still another embodiment of the method and apparatus for processing a metal plate according to the present invention will be described with reference to FIG. In this embodiment, one laser beam is split into four laser beams having the same output, each of the laser beams is focused on a metal plate, and each of the focused laser beams is simultaneously focused on the metal plate. By moving, four identical patterns are processed at the same time.

As shown schematically in FIG. 7, in the present embodiment, the laser beam 72 output from the laser beam generating unit 71 is converted into four laser beams 8 by the spectroscope 73.
1a to 81d. However, the laser beam generation unit 71 includes a laser oscillator, a beam former that changes the cross-sectional shape and the beam diameter of the laser beam, and the like. The spectroscope 73 is provided with semi-reflecting mirrors 74a to 74c and a total-reflecting mirror 74d. One-fourth of the incident laser beam is reflected by the semi-reflecting mirror 74a, and the incident laser beam is reflected by the semi-reflecting mirror 74b. One third of the beam is reflected, half of the incident laser beam is reflected by the semi-reflecting mirror 74c, and 100% of the incident laser beam is reflected by the total reflecting mirror 74d. As a result, the outputs of the four laser beams 81a to 81d from the spectroscope 73 are all equal.

The four laser beams 81a to 81d are incident on the processing heads 75a to 75d, respectively, and the condenser lenses 76a to 7d provided on the processing heads 75a to 75d, respectively.
The light is condensed at 6d, irradiated onto the metal plate 111, and processed. Further, on the back surface of the metal plate 111, each processing head 7
Liquid ejectors 77a to 77d are arranged so as to face 5a to 75d and have their center positions aligned.
The functions of these liquid ejectors 77a to 77d are the same as those shown in FIG. 1 or FIG.
It is fixed to 5d respectively. Also, although not shown,
A shield gas ejection port as shown in FIG. 1 or 5 or a ring-shaped member as shown in FIG. 6 is attached to each of the processing heads 75a to 75d.

The metal plate 111 is fed and positioned by the feeding roll 112 in the direction of arrow 113 in the figure. This feeding roll 112 is similar to FIG.
1 has a function of moving the laser beam irradiation position in the X-axis direction. Further, although not shown, a Y-axis moving base similar to that shown in FIG. 4 is provided, and the processing heads 75a to 75d are provided.
And the liquid ejectors 77a to 77d can be moved coaxially and integrally so as to draw the same trajectory. At this time, the metal plate 111 has four liquid ejectors 77a ...
Since it is supported by the liquid 77d through the liquid, the dross and the spatter due to the irradiation of the laser beams 81a to 81d do not directly contact the liquid ejectors 77a to 77d, and the metal plate 111 is supported smoothly and surely. Supporting accuracy is also good. Therefore, the metal plate 111
Can be easily delivered.

According to the present embodiment as described above, the above-mentioned 3
Not only the same effect as in the first embodiment can be obtained, but also four identical patterns can be processed at the same time. Also,
In this case, for each of the four identical patterns, one piece of control information such as the laser oscillation condition, the moving speed of the metal plate, the pressure and the flow rate of the liquid is sufficient, and thus the control becomes easy. Therefore, when a large number of patterns having the same shape are processed, low-cost and short-time production is possible, and mass production can be realized.

In the above embodiment, four identical patterns are processed at the same time, but a plurality of identical patterns other than four can be processed within a possible range.

Further, according to the above four examples, since it is possible to perform fine and highly accurate processing on a thin metal plate, it is difficult to perform processing by conventional etching or pressing. Moreover, it is suitable for forming a lead frame having a highly accurate size and shape from a metal plate.
In particular, in recent years, there has been a stricter demand for higher density mounting and higher integration of semiconductor chips, and in order to meet this demand, the lead frame on which the semiconductor chips are mounted is also required to have multiple pins and be fine and highly accurate. However, the present embodiment can sufficiently meet such a demand.

Further, in addition to the lead frame, a thin metal plate processed and having a fine and highly precise size and shape is used for a metal mesh sheet or screen printing used when solder plating is applied to a printed circuit board. There are metal masks and the like, and this embodiment can also be applied to these.

[0067]

According to the present invention, since the high pressure liquid is ejected from the back surface of the metal plate in the direction opposite to the ejection direction of the assist gas, the metal plate is not bent and deformed, and the nozzle tip and the metal plate are not deformed. The distance can be kept substantially constant, and the laser beam can be reliably focused on the metal plate.
Therefore, fine and highly accurate processing can be performed. Further, it is also possible to remove the melt, spatter, dust, generated gas or the like, which is a source of dross, by mixing it with the liquid.

Further, since the shield fluid is supplied so as to surround the assist gas, it is possible to correct the pressure balance between the front surface and the back surface of the metal plate.

Further, since the metal plate is supported by the liquid ejecting means via the liquid, the dross and spatter do not directly contact the liquid ejecting means, and the metal plate is supported smoothly and surely, and its supporting accuracy is high. Will also be good. Therefore, it is possible to stably and easily feed the metal plate at high speed and low speed while performing the processing.

Further, since the nozzle and the liquid ejecting means are coaxially and integrally formed, the pressures on the front surface and the back surface of the metal plate can be always balanced when processing is performed on any locus.

Further, since the through hole is provided at the center of the liquid ejecting means, it is possible to wash away the melt, spatter, dust, generated gas, etc. accompanying the processing together with the liquid, and keep the liquid ejecting means clean. This facilitates maintenance and inspection. Further, the function of the assist gas, which blows off the generated melt and suppresses the formation of dross, can be sufficiently exerted.

Further, since the ring-shaped member is attached coaxially with the nozzle, it is possible to prevent the liquid that has flowed out through the processing portion to the surface side from scattering, and the liquid received by the ring-shaped member can be used as a shield fluid. It can do the same thing.

Further, since the metal plate is not bent and deformed and is supported smoothly and surely, a large area can be machined at one time, and the machining efficiency becomes extremely good.

Since the processing apparatus as described above is capable of performing fine and highly accurate processing on a thin metal plate, it is possible to perform fine and highly accurate processing which has been difficult to process by conventional etching or pressing. A lead frame having dimensions and shape can be formed from a metal plate.

[Brief description of drawings]

FIG. 1A is a diagram showing a metal plate processing apparatus according to an embodiment of the present invention, in which an enlarged cross-sectional view of a lower portion of a processing head and a lower cover is shown, and FIG. FIG.

FIG. 2 is a cross-sectional view showing a state of processing using a conventional laser beam.

3 is a diagram showing a supply system of an assist gas, a shield gas, and a liquid in the metal plate processing apparatus of FIG.

4 is a machining head in the metal plate machining apparatus of FIG. 1;
It is a figure which shows a liquid ejector, a Y-axis moving stand, a Z-axis moving stand, etc.

5A is a view showing a metal plate processing apparatus according to another embodiment of the present invention, which is an enlarged cross-sectional view of a lower portion of a processing head and a lower cover, and FIG. It is a B sectional view.

FIG. 6 is a view showing a metal plate processing apparatus according to still another embodiment of the present invention, which is an enlarged cross-sectional view of a lower portion of a processing head and a lower cover.

FIG. 7 is a diagram schematically showing a metal plate processing apparatus according to still another embodiment of the present invention.

[Explanation of symbols]

 1 Processing Head 2 Nozzle 2A (Nozzle) Tip 2a Nozzle 2b (Nozzle) Tip 2c Ring Member 3 Condenser Lens 5 Assist Gas Supply Port 6 Liquid Ejector 6a Liquid Ejector 7 Lower Cover 7a Lower Cover 7b Hole 7c Through hole 8 Liquid supply port 8a Liquid supply port 9 Gap sensor 10 Shield fluid ejection port 11 Shield fluid supply port 21 Gas source 31 Gas source 40 Liquid 41 Tank 44 Motor 45 Pump 46 Pressure reducing valve 47 Flow control valve 60 Supply system control unit 61 Detection unit 62 Main control unit 63 Liquid control unit 71 Laser beam generation unit 72 Laser beam 73 Spectroscope 74a-74c Semi-reflecting mirror 74d Total reflection mirror 75a-75d Processing head 76a-76d Condensing lens 77a-77d Liquid ejector 100 Laser Beam 101 Metal plate 101a Processing part ( Away portion) 102 feed rolls 111 the metal plate 112 feed rolls 201 support arms 202 stand 203 fixed portion 206 Y-axis moving table 207 movable portion 209 motor

Claims (11)

[Claims] 1. A metal plate processing method for processing a metal plate by irradiating a metal plate with a pulsed laser beam while ejecting a high-pressure assist gas from a nozzle, wherein the laser beam of the metal plate is irradiated. A method for processing a metal plate, characterized in that a high-pressure liquid is ejected from a surface opposite to the surface on which the assist gas is ejected in a direction opposite to the ejection direction of the assist gas to support the metal plate. 2. The method for processing a metal plate according to claim 1, wherein a surface of the metal plate irradiated with the laser beam comprises:
A method for processing a metal plate, comprising supplying a shield fluid having a pressure lower than the pressure of the assist gas so as to surround the assist gas. 3. A metal plate processing apparatus for processing a metal plate by irradiating a metal plate with a pulsed laser beam while ejecting high-pressure assist gas from a nozzle, wherein the laser beam of the metal plate is irradiated. A metal plate having a liquid support means for ejecting a high-pressure liquid in a direction opposite to the ejection direction of the assist gas and supporting the metal plate through the liquid, on the surface opposite to the ejection surface. Processing equipment. 4. The metal plate processing apparatus according to claim 3, wherein a surface of the metal plate on which the laser beam is irradiated,
The apparatus for processing a metal plate, further comprising a shield fluid supply means for supplying a shield fluid having a pressure lower than the pressure of the assist gas so as to surround the assist gas. 5. The apparatus for processing a metal plate according to claim 3, wherein the nozzle and the liquid jetting means are coaxial and integrated with each other. 6. The metal plate processing apparatus according to claim 3, wherein the liquid ejecting means is provided with a detecting means for detecting a distance between the liquid ejecting means and the metal plate. apparatus. 7. The metal plate processing apparatus according to claim 3, further comprising flow rate control means for controlling a flow rate of the liquid ejected from the liquid ejection means. 8. The metal plate processing apparatus according to claim 3, further comprising pressure control means for controlling the pressure of the liquid ejected from the liquid ejecting means. 9. The apparatus for processing a metal plate according to claim 3, wherein a through hole is provided in the center of the liquid ejecting means. 10. The metal plate processing apparatus according to claim 3, wherein a ring-shaped member that receives the liquid ejected from the liquid ejecting means is coaxial with the nozzle on the surface of the metal plate irradiated with the laser beam. A metal plate processing device characterized by being attached. 11. A method for processing a lead frame, which comprises processing the lead frame with the apparatus for processing a metal plate according to any one of claims 3 to 10.