WO2013122099A1

WO2013122099A1 - Laser cutting method and laser cutting device

Info

Publication number: WO2013122099A1
Application number: PCT/JP2013/053383
Authority: WO
Inventors: 雅典赤木; 信一郎北川
Original assignee: 日産自動車株式会社; オートモーティブエナジーサプライ株式会社
Priority date: 2012-02-13
Filing date: 2013-02-13
Publication date: 2013-08-22
Also published as: JP5997911B2; JP2013163213A

Abstract

This laser cutting method and this laser cutting device address the problem of reliably removing an unneeded portion generated during laser cutting. In the present invention, the problem is solved by: further setting second cutting lines (paths c and h) for irradiation with a laser beam in regions on the side removed as the unneeded portion (scrap (120)) along parts (paths b and f) of first cutting lines (paths a, d, b, e, f, g, and i) for cutting out the product profile (101) from a sheet-shaped member; and beaming laser light along the first cutting lines and the second cutting lines.

Description

Laser cutting method and laser cutting apparatus

The present invention relates to a laser cutting method and a laser cutting device, and more particularly to a laser cutting method and a laser cutting device for cutting a sheet-like member with a laser.

In recent years, lasers have been used for cutting sheet-like members such as metal foils. Such laser cutting is also used for cutting when forming an electrode tab in manufacturing a battery (Patent Document 1).

JP 2009-032504 A

However, when forming the battery tab, if the metal foil that is the base of the battery tab is cut with a laser, burrs are generated along the cutting line irradiated with the laser beam. There is a problem that the burr may be caught when removing the cut unnecessary portion (scrap) and cannot be removed well.

Therefore, an object of the present invention is to provide a laser cutting method and a laser cutting apparatus that can reliably remove unnecessary portions generated during laser cutting.

In order to achieve the above object, the laser cutting method of the present invention sets a first cutting line for cutting a product shape from a sheet-like member, cuts along a part of the first cutting line, and cuts from the first cutting line. A second cutting line for further laser irradiation is set in a region to be removed as an unnecessary portion afterwards. Then, laser light is irradiated along the first cutting line and the second cutting line.

In order to achieve the above object, a laser cutting apparatus of the present invention has a laser irradiation means and a control means so that the control means follows the first cutting line and the second cutting line in the laser cutting method. Further, the irradiation direction of the laser light emitted from the laser irradiation means is controlled.

According to the present invention, since the second cutting line is provided along a part of the first cutting line that separates the member by irradiating the laser beam, in the portion irradiated with the laser beam by the second cutting line, The generated burrs will be separated from the unnecessary part side. Thereby, when removing an unnecessary part, the part which an unnecessary part side does not catch on the product side is made. Since there is a portion that is not caught by this product, the unnecessary portion is easily detached from the product side when the unnecessary portion is pulled away, and the unnecessary portion can be reliably removed.

It is the schematic for demonstrating the laser cutting device to which this invention is applied, (a) is a top view which shows the principal part seen from the top, (b) is a side view. It is a perspective view which shows the external appearance of the battery by which lamination sealing was carried out. (A) is a top view which shows the state before tab formation of a battery, (b) is a top view which shows the state after tab formation of a battery. It is explanatory drawing for demonstrating the cutting operation by a laser cutting device. It is explanatory drawing for demonstrating the cutting operation by the laser cutting device following FIG. It is an enlarged plan view of the electrode foil part for demonstrating the cutting line path | route used as the irradiation trace of the laser beam to electrode foil. It is an enlarged plan view of the electrode foil part for demonstrating the other cutting line path | route used as the irradiation trace of the laser beam to electrode foil.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Moreover, the size and ratio of each member in the drawings are exaggerated for convenience of explanation, and are different from the actual size and ratio.

1A and 1B are schematic views for explaining a laser cutting apparatus to which the present invention is applied, in which FIG. 1A is a plan view showing a main part viewed from above, and FIG. 1B is a side view.

This laser cutting device is a device for forming an electrode tab from an electrode foil drawn from the exterior of the battery. In the present embodiment, the electrode foil is a sheet-like member that creates a product shape by laser cutting. In this embodiment, the metal foil which has come out from the exterior of the battery in a state before being cut into the shape of the electrode tab which is a product shape is referred to as an electrode foil.

As shown in FIG. 1, a laser cutting device 1 includes a stage 11 on which a battery 100 as a workpiece is placed, a laser irradiation device 12 that irradiates laser light, and a scrap removal unit 13 that removes unnecessary portions (scrap 120) after cutting. Become.

The stage 11 is integrally attached with a base 14 on which electrode foils 111 and 112 (see FIG. 3) extending from the battery 100 are placed. A step is provided between the stage surface and the pedestal surface. This is because the

electrode foils

111 and 112 are placed on the pedestal 14 when the laminate-sealed portion of the battery 100 (referred to as the main body portion 110) is placed on the stage 11. .

By providing this pedestal 14, the

electrode foils

111 and 112 are not deformed when the scrap removing unit 13 is pressed against the scrap 120 from above, as will be described later.

The laser irradiation device 12 includes a laser irradiation unit 21 (laser irradiation unit) that irradiates the

electrode foils

111 and 112 with laser light, and a control unit 22 (control unit) that controls the laser light to draw a locus along a predetermined cutting line. )have. The laser irradiation unit 21 is attached to, for example, an arm 25 extending from the outside of the stage 11. The laser irradiation unit 21 rotates around two axes (axis 26 and axis 27) by motors (not shown). Instead of the arm 25 as described above, a laser irradiation unit 21 may be provided at the tip of the arm of the multi-axis robot so that the direction of the laser beam can be freely changed.

The control unit 22 controls the motors of the

shafts

26 and 27 so that laser light is irradiated along a cutting line to be described later. The control unit 22 also controls on / off of laser irradiation and the operation of the scrap removing unit 13. Although the control unit 22 is illustrated in FIG. 1B, the control unit 22 does not have to be in the vicinity of the stage 11, and is connected to each unit by a signal line or the like, and where the laser beam direction can be freely controlled. There may be.

The laser irradiation unit 21 is connected to a laser generation source (not shown), and laser light guided from the laser generation source is emitted from the tip of the laser irradiation unit 21.

The scrap removing section 13 is provided with two identical ones for removing scrap coming out from each of the two electrode tabs (positive tab and negative tab). Each scrap removing unit 13 includes an arm 31 and a suction pad 32 provided at the tip of the arm 31. The suction pad 32 has a motor (not shown) that moves the arm 31 about the fulcrum 33 so as to draw an arc (shown a). Although not shown, a suction port is provided on the contact surface of the suction pad 32 with the electrode foil 111 (112) to suck the electrode foil 111 (112). An air suction device is provided for this adsorption operation.

Here, an example of a battery will be described. FIG. 2 is a perspective view showing the appearance of a laminated battery. FIG. 3A is a plan view showing a state before tab formation, and FIG. 3B is a plan view showing a state after tab formation.

The battery 100 described here is a battery in which a power generation element is sealed with a laminate film. As is well known, a laminate film has a laminated film structure in which a metal foil (for example, an aluminum foil) is sandwiched between resin films. The battery 100 covered (sealed) with the laminate film is entirely covered with the laminate film 200 and has a power generation element inside. In the illustrated battery 100, the portion covered with the laminate film 200 (with the power generation element included) is referred to as a main body portion 110. In this battery 100, two tabs (positive electrode tab 101 and negative electrode tab 102) serving as electrode terminals are drawn from one side. The laminate film 200 is sealed by being bonded by thermal fusion or an adhesive at the peripheral edge portion 210 thereof.

In this battery 100, in the state before the tab formation, as shown in FIG. 3A, the electrode foils 111 and 112 before the tab is formed are left outside the main body 110 as they are. There are two electrode foils 111 and 112, one for the positive electrode and one for the negative electrode. Such electrode foils 111 and 112 are formed into the shape of the positive electrode tab 101 and the negative electrode tab 102 by laser cutting, as shown in FIG.

Next, the cutting operation by the laser cutting device 1 will be described.

4 and 5 are explanatory diagrams for explaining the cutting operation by the laser cutting device 1.

In the cutting operation by the laser cutting device 1, first, the battery 100 is placed on the stage 11, as shown in FIG. The battery 100 is in a state before the electrode foils 111 and 112 are cut into a tab shape (referred to as before the tab processing). At this time, the scrap removing unit 13 is in an open state as shown in FIG. When the battery 100 before the tab processing is placed on the stage 11, the electrode foils 111 and 112 are positioned so as to be on the pedestal 14. For this positioning, for example, an abutting member for abutting and positioning the end of the battery 100 on the stage 11 may be provided.

Subsequently, in the state shown in FIG. 4A, laser light is irradiated from the laser irradiation unit 21 to the electrode foils 111 and 112 of the battery 100 before the tab processing along a predetermined cutting line. This cutting line will be described later.

After the cutting, as shown in FIG. 4B, the arm 31 is tilted about the fulcrum 33 and the suction pad 32 is brought on the electrode foils 111 and 112 of the battery 100. In this state, the suction pad 32 sucks the scrap 120.

Thereafter, as shown in FIG. 5, the suction pad 32 is returned to the original position. At this time, the suction pad 32 moves in an arc shape. Therefore, the scrap 120 is not lifted vertically upward with respect to the electrode foils 111 and 112 of the battery 100 but is pulled obliquely (in the direction of the arrow b in the figure) in the direction above the fulcrum 33, which is the direction in which the suction pad 32 opens. Will be.

Note that the scrap 120 is collected by dropping the suction force when the suction pad 32 is opened approximately 45 degrees to 90 degrees, and dropping the scrap 120.

Next, the cutting line (laser beam irradiation locus) at the time of laser cutting will be described.

FIG. 6 is an enlarged plan view of an electrode foil portion for explaining a cutting line that becomes an irradiation locus of laser light to the electrode foil.

The cutting line that becomes the irradiation locus of the laser beam is set so that the laser beam can be irradiated with a single stroke. And part of the cutting line overlaps. That is, as shown in the figure, the cutting line that becomes the locus of the laser beam starts from the path a, passes through the path d following the path a, passes through the path b, passes through the path c that overlaps the path b, and then passes again. d, route b, route e, f, g, route h overlapping route f, route f, g, route i, route i. Here, the overlapping routes b and c and routes f and h are not completely on the same line, but are shifted toward the area where the routes c and h are on the scrap 120 side with respect to the routes b and f. This deviation is paths d and g. In this way, two island-shaped scraps 121 having substantially triangular shapes are formed by the routes b, c, d and the routes f, g, h together with the scrap 120 separated. Here, the paths a, b, d, e, f, g, and i are the first cutting lines, and the paths c and h are the second cutting lines. Therefore, the second cutting line is set along a part of the first cutting line in the middle of the first cutting line.

Note that the order of the routes d, b, and c and the routes f, g, and h may be reversed. That is, as shown in FIG. 7, the entire route passes through routes a, c ′, b ′, and d ′, passes again through c ′, passes through routes h ′, g ′, and f ′, and passes again through route h ′. The order may be to pass through the route i. In this case, the traveling direction of the laser trajectory of the cutting line when irradiating the laser with a single stroke is such that the second cutting line is performed first, and the effect is the same.

Thus, by setting the cutting line so that the island-shaped scrap 121 can be formed, the burr generated on the tab 101 side as a product and the burr generated on the scrap 120 side are separated by the amount of the island-shaped scrap 121. For this reason, when the scrap 120 is pulled away, the burr at this portion is not caught. The cut out island-shaped scrap 121 is a very small object, and may be sucked and collected by, for example, a suction machine (suction cleaner).

In the figure, only the electrode foil 111 to be the positive electrode tab 101 is shown, but the electrode foil 112 to be the negative electrode tab 102 has the same shape, and thus the first cutting line and the second cutting line are set similarly.

The preferred position for setting the overlapping route does not have to extend over the entire length of the cutting line, and may be a part of it as shown. This is determined by the direction in which the scrap 120 is removed and the position where the scrap 120 is sucked by the suction pad 32.

In this embodiment, as described above, when removing the scrap 120, the scrap 120 is sucked by the suction pad 32, and the suction pad 32 is moved in an arc shape and removed. For this reason, in a plan view (when the electrode foil is viewed from above), the paths b and f of the cutting line in the same direction as the locus of the arc drawn by the suction pad 32 are the gap (cutting portion) between the tab 101 and the scrap 120. Does not spread. For this reason, in the paths b and f, when the scrap 120 is removed, the burrs move in a rubbing direction and are easily caught. On the other hand, in the cutting line paths a, d, e, g, and i in the direction perpendicular to the movement track of the suction pad 32, the gap between the tab 101 and the scrap 120 moves in a plan view. For this reason, the burr is moved in a direction away from the burr and is not easily caught.

In the example of the cutting line described above, in plan view (when the electrode foil is viewed from above), the first cutting line along the paths b and f in the same direction as the arc trajectory drawn by the suction pad 32 respectively. Two cutting line paths c and h were provided. This has already been described and is the most preferred form.

However, the present invention is not limited to this. For example, in plan view (when the electrode foil is viewed from above), a second cutting line that overlaps only in one of the paths in the same direction as the arc trajectory drawn by the suction pad 32 is provided. Just as good.

This is related to the suction position of the suction pad 32 with respect to the scrap 120. The closer the suction position is to the cutting line and the wider the part is, the less affected the burr is. This is because the shape of the scrap 120 is difficult to deform at the cutting line portion close to the position where it is sucked by the suction pad 32, and even if a burr is caught at that portion, it can be removed without being deformed. On the other hand, the cutting line portion far from the position attracted by the suction pad 32 is easily deformed. Therefore, if a burr is caught, the scrap 120 may not be removed due to deformation while being caught. For this reason, when the second cutting line along the first cutting line sucks the protruding portion 125 of the two protruding

portions

125 and 126 of the scrap 120 having a concave shape, the second cutting line starts from the suction position. Even if it is provided on the far side of the protruding portion 126 side, it is effective.

When these are put together, the position where the second cutting line along a part of the first cutting line is provided is as follows.

First, when removing the scrap 120, the scrap 120 is moved obliquely upward and removed. At this time, the second cutting line is set at a position along the portion where the gap formed by cutting with the first cutting line does not widen in plan view. In particular, it is most preferable to provide the second cutting lines for the path portions of all the first cutting lines that are not widened in plan view.

Secondly, since the scrap 120 has a concave shape in which two projecting

portions

125 and 126 projecting to the tab shape (product shape) side are connected, of the two projecting

portions

125 and 126 having the concave shape. One (protruding part 125) of this is adsorbed with an adsorption pad. The second cutting line is provided in a region along the first cutting line between the protrusion 126 on the side not sucked by the suction pad 32 and the product shape.

In addition, when the scrap is not a concave shape but simply cuts off a rectangle, the second cutting line may be set at a position along a portion where the gap formed by cutting with the first cutting line does not widen in a plan view. .

In this way, by setting the second cutting line only on the part where the product shape is not cut, but only on the part where the burr is likely to be caught, the scrap can be surely removed and the laser irradiation path can be shortened as much as possible. be able to.

According to the embodiment described above, the following effects are obtained.

(1) By providing the second cutting line along a part of the first cutting line, the burrs on the tabs 101 and 102 (product) side after cutting and the burrs on the scrap 120 (unnecessary part) side formed by laser irradiation are provided. During this period, two laser irradiation trajectories are formed. In the portion irradiated with the laser along the second cutting line, the burrs on the tab (product) side after cutting and the burrs on the scrap 120 (unnecessary portion) side are not in direct contact with each other. It won't get caught. For this reason, the burr is hardly caught at the portion where the burr is most easily caught, and the scrap 120 can be reliably removed.

(2) By providing the second cutting line in the middle of the first cutting line, laser light can be irradiated along the first and second cutting lines without stopping laser irradiation.

(3) By setting the first cutting line and the second cutting line to be drawn with a single stroke, cutting can be performed at once without stopping the laser irradiation on the way. For this reason, the laser irradiation time can be shortened as much as possible.

(4) When the scrap 120 (unnecessary portion) is removed, the second cutting line is the first position where the gap between the product shape after cutting and the scrap 120 does not widen with the movement of the scrap 120 in plan view. It was decided to set in the area along one cutting line. For this reason, it is possible to prevent the burr from being caught at a portion where the burr is easily caught during scrap removal. In addition, since the second cutting line is provided only for the part that is most likely to catch the burr as described above, the laser irradiation trajectory is not extended as much as compared with the case of cutting only the first cutting line. In addition, scrap removal can be reliably performed.

(5) The scrap 120 (unnecessary portion) has a concave shape to which two projecting

portions

125 and 126 projecting toward the tabs 101 and 102 (product shape) are connected. Since the scrap 120 is removed by adsorbing and removing the portion of one of the projecting portions 125 with the suction pad 32, the second cutting line is formed on the side of the projecting portion 126 that is not attracted by the suction pad 23. It was provided along the cutting line. As a result, the burr can be prevented from being caught at a portion where the burr is more easily caught at the time of scrap removal.

(6) The control unit 22 is controlled to irradiate the laser beam emitted from the laser irradiation unit 21 along the first cutting line and the second cutting line described above. Thereby, in the part irradiated with the laser along the 2nd cutting line, the catch of a burr | flash becomes less and it becomes possible to remove the scrap 120 reliably.

The embodiment to which the present invention is applied has been described above, but the present invention is not limited to the above-described embodiment.

For example, the second cutting line may be set in an area on the scrap (unnecessary part) side substantially parallel to the first cutting line. In this case, the island-shaped scrap has a substantially rectangular shape.

Also, the second cutting line may be set in parallel to the scrap side area by a small amount that does not allow island scrap. In this case, the laser beam is irradiated again in the direction returning from the top of the portion irradiated with the laser beam according to the first cutting line, and this becomes the second cutting line. When laser irradiation is continued with a single stroke, the laser beam is further irradiated in the direction of the first cutting line. Therefore, in this case, laser light irradiation is performed three times on the same path. For this reason, the burrs formed by laser irradiation of the first cutting line are further melted and disappeared by two times of laser irradiation, and the burrs themselves are reduced and are not caught. However, if the second cutting line is set at the same position as the first cutting line, the laser beam is irradiated several times on the same cutting line. For this reason, the area | region which lose | disappears with a laser beam may become large, and there exists a possibility of reducing a product shape. Therefore, it is preferable that the second cutting line is set slightly in the area on the scrap side to such an extent that island-shaped scrap cannot be generated with respect to the first cutting line.

Further, the second cutting line may be provided not only on the part along the paths b and f but also on the part along the path e. By doing so, although the irradiation path of the laser beam becomes long, the burrs are less caught and the scrap 120 can be removed more reliably.

Also, the suction pad 32 for scrap removal is lowered after the laser irradiation, but this is to avoid interference between the laser beam and the scrap removal device (mainly the suction pad 32 and the arm 31). Therefore, by arranging the laser light and the scrap removal device so that they do not interfere even during laser irradiation, the suction pad 32 is lowered to the electrode foils 111 and 112 before laser irradiation, and after laser cutting, suction is performed. The pad 32 may be raised. As a result, the electrode foils 111 and 112 can be held by the suction pad 32 before the laser irradiation.

In addition, the battery has been described by taking an example in which two electrode tabs are drawn from one side. However, the battery is not limited to such a form. For example, the electrode tabs are drawn from two opposite sides. The present invention can also be applied to other batteries.

Furthermore, although embodiment mentioned above demonstrated as an example forming the tab shape of a battery as a sheet-like member which is a cutting | disconnection object, this invention is not limited to the tab formation of a battery, Laser of various sheet-like members It can be applied to cutting.

In addition, as long as the present invention has a configuration defined in the scope of claims, a configuration other than those described here may be added or a configuration may not exist, and various forms are possible. Needless to say, it is included in

Furthermore, this application is based on Japanese Patent Application No. 2012-28359 filed on February 13, 2012, the disclosures of which are referenced and incorporated as a whole.

1 Laser cutting device,
11 stages,
12 Laser irradiation device,
13 Scrap removal section,
14 pedestal,
21 Laser irradiation part,
22 control unit,
25 arms,
32 suction pads,
33 fulcrum,
100 batteries,
101, 102 tabs,
110 body part,
111, 112 electrode foil,
120 scrap,
121 island scrap,
125, 126 Projection.

Claims

Set a second cutting line along the part of the first cutting line for cutting out the product shape from the sheet-like member, and further performing laser irradiation on the region to be removed as an unnecessary part after cutting from the first cutting line, A laser cutting method comprising irradiating laser light along the first cutting line and the second cutting line.
The laser cutting method according to claim 1, wherein the second cutting line is set in a region along the middle of the first cutting line.
3. The laser cutting method according to claim 1, wherein the second cutting line is set so as to be drawn with one stroke together with the first cutting line.
When the unnecessary part is removed, the second cutting line is the first cutting line in which a gap between the product shape after cutting and the unnecessary part does not widen as the unnecessary part moves in a plan view. The laser cutting method according to any one of claims 1 to 3, wherein the laser cutting method is set in a region along the line.
The unnecessary portion has a concave shape in which two protruding portions protruding to the product shape side are connected, and the unnecessary portion is removed by adsorbing one of the protruding portions with an adsorption pad. 5. The method according to claim 1, wherein the second cutting line is provided in a region along the first cutting line between the protruding portion on the side that is not sucked by the suction pad and the product shape. The laser cutting method as described.
Control for controlling an irradiation direction of laser light emitted from the laser irradiation means so as to follow the first cutting line and the second cutting line by the laser irradiation means and the laser cutting method according to any one of claims 1 to 5. And a laser cutting device.