JPH0775911A - Automatic cutting method for steel plate - Google Patents

Abstract

PURPOSE:To products freely with high precision from an adurol plate. CONSTITUTION:When a steel plate to be cut is carried onto a table for a marking-off device, a marking-off scheduled line is searched for the periphery of a base material teaching line on the steel plate until equal spaces A1, A2, B1, B2 are formed in the cross direction and the longitudinal direction, so that a marking-off line is determined in optimum conditions and coordinates (x1, y1, x2, y2, x3, y3, x4, y4) at the corner of the marking-off line are determined. In accordance with such data, automatic NC cutting is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nesting method for gas-cutting a hot-rolled thick steel plate, and more particularly to a steel plate from a sound portion of an AS ROLL plate. The present invention relates to a nesting method and an NC automatic cutting method based on the nesting method that can perform the optimum and high efficiency.

[0002]

2. Description of the Related Art In a steel mill, a hot-rolled thick steel plate is cut into a predetermined product size by using a cutting machine.
This cutting method is roughly classified into mechanical cutting methods such as double side shear and end shear, and gas, plasma,
There is a fusing method using a laser or the like. The mechanical cutting method enables high-efficiency cutting, but the cutting thickness is limited.
(Currently, it is not possible to cut a steel plate with a thickness of about 50 mm or more.) Also, when performing complicated plate cutting from a single material, or when the material has a large lateral bend (camber). Not applicable.

Therefore, in such a case, the fusing method is used. Therefore, both a mechanical cutting machine and a fusing-type cutting machine are generally installed in a plate rolling mill. It should be noted that cutting by the fusing method (hereinafter collectively referred to as gas cutting) requires a large number of man-hours as compared with the mechanical cutting method, productivity is low, and the working environment is bad, so labor saving in recent years. The promotion of automation and automation is required.

By the way, in the above-mentioned gas cutting, a gas cutting machine having a gate-type structure is run on a rail, and steel plates to be cut (sides having ears and tail ends at the end) are provided on a surface plate (table). As-rolled steel sheet with crops (hereinafter referred to as "material") is cut into a predetermined product size.

In this cutting operation, the material is distributed by a crane (or other conveying means) and then finished in the following procedure.

First, the operator considers the cutting margin for each material, and cuts product dimensions and required test piece dimension lines (marking lines).
Perform the cutting work while moving the cutting machine aiming at this marking line After the cutting, inspection of the cross section (especially hot water and dross residue, cross section roughness, crater flaw, dimensional accuracy, etc.) Carry out the products that will be stamped or labeled by crane or other transportation means.

A technique relating to the cutting of a steel sheet is disclosed in, for example, Japanese Patent Laid-Open No. 1-95872.

[0008]

However, in the above-mentioned prior art, after the shape recognition device recognizes the planar shape of the material and the placement state from the predetermined reference line, the planned cutting line is determined, The material is cut one by one on the spot (the material is not moved to another place by a crane or the like), and the series of operations up to the above is performed in series.

There is a case where the raw material as rolled has winding at its end and a local warp occurs, and it is not always necessary to determine the product removal only from the planar shape of the raw material. I can't. This becomes a problem especially in a situation where the cutting margin is reduced due to the recent high yield design. Also,
In the case of a degassed material having a relatively thick material, the amount of entrainment tends to be large, and therefore the judgment requires visual observation or means using another detector. (A solution to this problem in the present invention will be described in detail in the teaching method described later.) Further, when performing automatic cutting using numerical control (hereinafter NC), numerical input is indispensable, There are various cutting patterns for taking a plurality of products and a test piece (TP) from one material.

Therefore, it is extremely troublesome to input a numerical value to the NC each time. For this reason, it takes a lot of time to complete the cutting, and work errors are likely to occur. As a result, work efficiency and productivity are reduced.

If a computer is used to design a product or TP, marking lines by NC, automatic selection of cutting model (cuttable plate thickness limit, determined by efficiency comparison), NC cutting condition instruction (selection of cutting torch number to be used) , The order of transfer of each torch, the instruction of cutting speed, etc.) are automatically scheduled, so that the work efficiency and the degree of freedom can be dramatically improved.

Further, if the respective functions of the cutting work (marking, cutting, and marking display) are continuously processed at the same place as in the conventional example, it is impossible to perform parallel processing on a plurality of steel plates. However, there is a drawback that work efficiency is poor.

When cutting a plurality of products and TP from one material, the amount of movement on the surface plate due to thermal deformation of each member is minimized. Therefore, the cutting order is optimized in order to obtain product dimensional accuracy. Is an important point.

Therefore, an object of the present invention is to provide a teaching and nesting method for steel sheet cutting which enables cutting from an azroll plate to be performed efficiently and freely by a cutting means adopting NC, and an automatic NC cutting method based on the teaching and nesting method. To provide.

[0015]

In order to achieve the above-mentioned object, the present invention according to claim 1 is characterized in that when a steel sheet to be cut is carried onto a table of a scribe device, a scribe line is formed on the steel sheet. The edge of the sound part is searched until uniform intervals are formed in the width direction and the length direction, and the marking line is determined when the optimum condition is obtained by this search, and the corner line of the marking line is determined. It is a nesting method that determines each coordinate, and based on this, a cutting torch route for cutting out multiple products is automatically set for the material to be cut, and automatic cutting is performed by a numerical control method. In addition, according to claim 3, in an automatic cutting method of a numerical control system for automatically cutting a plurality of products from the material by fusing based on the marking lines formed on the material surface, the product to be acquired is obtained. If the cutting line between is T-shaped when plasma cutting, and may become cross when gas cutting,
The flatness of these products is set, and stable cutting conditions are set without scratching the product.
Further, in claim 4, the edged surface of the material is detected based on the teaching line, and the cutting torch is moved from the outside to the inside at a speed slower than the steady cutting speed of the product based on the detection result, and at the same time, the product cutting is performed. In the area, we try to keep the speed constant.

[0016]

According to the above-described means, the planned marking line is set based on the teaching data obtained by teaching the periphery of the steel plate to be cut, and is it possible to remove the cutting line with the shortest distance around the cutting line with respect to the teaching line? The marking line is determined by searching whether or not the cutting coordinate point is obtained. As a result, it is possible to perform plate cutting of the product from the central portion of the sound portion of the azroll base material while avoiding the cropping portion and the winding portion, which enables automatic NC cutting.

Furthermore, when a plurality of products are cut into a material based on the data about the products and the cutting line between the plurality of products is T-shaped or cross-shaped, the cutting conditions are set separately for plasma cutting and gas cutting. Automatic disconnection is performed. Further, in order to prevent the product from moving on the table due to thermal deformation or the like, the products are sequentially separated from the outer product. As a result, high cutting dimension accuracy can be ensured.

Further, the end face detection sensor detects the end face of the material with ears on the basis of the teaching line, the torch speed of the gas cutting torch is reduced at the ears, and is returned to a steady speed when cutting the product. This enables automatic cutting from the edge surface of the material with ears.

[0019]

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

FIG. 1 is an explanatory view for explaining a nesting method for cutting a steel sheet according to the present invention. FIG. 2 is a plan view showing a schematic configuration of a steel sheet cutting line to which the nesting method for steel sheet cutting according to the present invention is applied.

As shown in FIG. 2, the transfer table 10, N
Scribing device 12 by C (numerical control), plasma & gas cutting machine 14 by NC, gas cutting machine 16 by NC
(Each of the cutting machines 14 and 16 is equipped with a cutting platen) is continuously arranged in a straight line. A temporary storage area 18 is provided in parallel with this line, and a transport table 24 is provided in parallel with the temporary storage area 18. A stamping machine 26 is provided at the upper part of the rear stage of the transport table 24.
Also, a marking device 28 is installed. An overhead crane 30 is movably arranged on the ceiling of the building so as to be movable to the upper parts of the marking device 12, the cutting machines 14 and 16, the temporary storage 18 and the transport table 24.

The marking device 12, the plasma / gas cutting / combining machine 14, and the gas cutting machine 16 are controlled by a control device and a computer (not shown) for controlling the whole. The temporary storage area 18 is used for the finished marking material 2
This is a place for temporarily storing the cutting completion material 22 which has been cut by the cutting machine 0 and the cutting machine. Also, the embossing machine 26
Is used to mark numbers and symbols on the surface of the steel plate, and the marking device 28 is also used to print numbers and symbols on the surface of the steel plate.

The product flow will be described below.
The material carried into the marking device 12 by the transport table 10 is automatically marked, and the marking completed material 20 with the marking completed is carried into the temporary storage area 18. The target material here is the as-roll base material with ears on the sides and crops on the ends, and a plurality of test pieces (T
P) is attached. In addition, there are cases where the camber is large and a plurality of products are divided and cut, and depending on the material, a plate increase treatment and a plate reduction (switching) treatment are performed.

The marking completion material 20 is transferred by the overhead crane 30 from the temporary storage 18 to the cutting machines 14, 16 or the transport table 24 in accordance with a command. The cutting completed material 22 that has been cut by the cutting machine 14 or the cutting machine 16 is
It is transported to the temporary storage area 18 again, and then the overhead crane 30
Then, it is transferred onto the transport table 24, carried into the marking machine 26 and the marking device 28, and subjected to predetermined marking and marking.

The marking operation in the marking device 12 is as follows.
(1) Supplying the material → (2) Attaching the barcode to the surface of the material (this meaning will be described later) → (3) Reading the barcode number using the barcode reader installed in the marking device → (4 ) Teaching → (5) Nesting →
(6) NC marking, automatic setting of cutting conditions → (7) Convert to NC data → (8) Transfer NC data to data server (buffering) → (9) Automatic marking (predetermined product on the surface of material, TP removal Enter the marking line of the product, TP
(Automatically fill in the number) → (10) Discharge of the scribbled material, and the above process is performed.

As described above, in the marking operation, a plurality of materials are collectively processed, and at the same time, all cutting setups are completed. And the various data necessary for NC disconnection, the material number (corresponding to the bar code number) as a key,
Store in data server.

Here, the meaning of using the bar code will be supplementarily described. The material for which the above marking has been completed will be placed in the temporary storage area 18.
A plurality of sheets will be temporarily placed on the cutting machine 14 or 1.
At the time when the material is supplied to 6, the material number must be recognized by the cutting machine 14 or 16, and if this is manually input, there is a risk of annoyance and an input error. I used a barcode to match the numbers.

Next, after the material is supplied from the temporary storage 18 to the surface plate of the cutting machine, the cutting work in the cutting machine 14 or 16 is executed in the following procedure.

(1) Read the bar code number pasted on the surface of the material using the bar code reader mounted on the cutting machine → (2) Cutting the material under the conditions corresponding to the bar code number The conditions are automatically requested to the data server, and the data is transferred to the NC controller of the cutting machine → (3) Using the marking line to read the inclination of the material on the surface plate → (4) Based on the inclination angle , NC cutting of products and test pieces along the marking line → (5) Product inspection, maintenance → (6) Discharge.

The marking line is necessary for the following reason.

I. Since the place where the material is taught → the nesting is different from the cutting place, at the time of starting the cutting by the cutting machine, a mark indicating the cutting start point is necessary in terms of machine operation.

Therefore, if the marking line is written on the material, the cutting start point becomes clear, and at the same time, work mistakes can be prevented.

II. When reading the inclination angle of the material of (3) on the surface plate, at least among the rectangular marking lines,
One is needed. The remaining planned cutting lines (marking lines) are stored in the data server, and there is no problem in the operation of the machine, and NC cutting can be performed on all the planned cutting routes (the lines do not have to be included in the material above). . Therefore, if there is a marking line with a length (about 4 to 5 m) that allows the inclination angle of at least one material to be read, the cutting machine is transferred to the cutting surface along this line, and the inclination angle of the material is controlled by the NC controller of the cutting machine. The automatic disconnection is possible by making the user recognize.

III. Since the planar shape of the material is indefinite, if the rectangular marking line is written on the surface of the material, the operator can know the planned cutting line, which is an advantage that the operator can work with peace of mind.

Next, the execution of the marking process by the marking device 12 will be described with reference to FIG.

Incidentally, S in FIG. 6 means a step.

First, as shown in FIG. 2, the material is carried into the marking device 12 (S101), and teaching is performed by this marking device (S102).

The teaching process is performed by using a CCD camera mounted on the marking device, and moving the position of the camera together with the marking device along the outer edge of the material by the operator's visual observation and remote operation to determine the outer peripheral point of the material. Each coordinate point from at least 4 points to about 20 points is stored in the data creation computer 21. That is, in order to cut a predetermined product from a sound part of a material having an irregular planar shape, the sound range of the material is recognized. If, at this time, there is a roll-in of the edge of the steel plate or a local warp, mark the unhealthy part on the surface of the material with chalk etc. in advance, and use the CCD camera to mark the outer edge of the material. If they are made visible together, it is possible to recognize the healthy range in a form that excludes that part.

Before the teaching process, the bar code is issued based on the information from the host computer 10 and attached to the surface of the material, and the bar code is also mounted on the marking device. The data is read by the reader and stored in the data creation computer 21 together with the teaching data. During this period, the material is kept stationary on the surface plate (or table) in order to store the teaching coordinate points of the material.

Next, the data creation computer 21 performs nesting (product and TP removal design) (S103).

The nesting means the product and the T based on the information from the host computer 10 from the substantially central portion of the sound range of the material recognized by the previous teaching.
The P cutting out position is determined. By automatically performing this process, it is possible to accurately design products and TPs in the shortest time.

Next, the NC data necessary for performing the NC cutting by the NC data converter (not shown) on the data from the data creating computer, that is, the NC marking condition (setting of the torch transfer order and the required data). Converting to the entry position (coordinates) of manufacturing number etc. and NC cutting conditions (cutting machine selection, cutting path route setting, torch transfer order, torch speed, acceleration / deceleration, distance between torch and steel plate, etc.) (S1)
04). Based on this marking condition data, marking device 1
In step 2, the marking process is automatically performed (S105). As described above, the content of the marking is the automatic marking of marking lines on the steel plate,
The production number and test piece number are automatically entered on the steel plate. The material on which the marking has been completed is transported to the temporary storage 18 by the overhead crane 30.

The marking results are accumulated in the data server and read out at the time of cutting together with the NC cutting conditions described above.
It is used as automatic cutting control data for the designated cutting machine 14 or 16 (S106). Before cutting, the material to be cut from the temporary storage 18 is the overhead crane 3
0 is used (the operation is manual) and is carried into the surface plate of the cutting machine.

At the time of this automatic cutting, the cutting machine 14 or 16
Tracking is performed based on the bar code read by the bar code reader installed in the, and as described above, automatic disconnection is started based on the disconnection condition from the data server. The cut product is transported to the next process (S1
07), the attached test piece (TP) is sent to the test piece processing center. Further, the cutting record for the cut product is fetched into the host computer.

Here, a nesting method for steel sheet cutting according to the present invention will be described with reference to FIG.

The product 1 and the product 2 are obtained by cutting the material in the middle. In many cases, the material carried into the marking device 12 is carried with an inclination (plate skew angle Θ). . Therefore, it is necessary to carry out the marking under the condition of the plate skew angle Θ = 0. In addition, the material has crops, wraps, etc., and it is necessary to avoid this and plate the product.

Therefore, in the present invention, nesting is automatically performed by the following procedure.

I Calculate the skew angle Θ II Rotate the coordinate axes III Set the marking line for the width of the plate IV Search the shortest distances A1 and A2 V Determine the marking line for the width of the plate (A1 = A2) ) VI Set the marking line on the plate length side VII Search the shortest distances B1 and B2 VIII Determine the marking line on the plate length side (B1 = B2) IX Each cutting coordinate point (x1, y1) to (x4, y4) The X marking screen is displayed on the X display screen (CRT of the terminal device of the computer). XI Move to the automatic cutting path setting.

By carrying out such a treatment, it is possible to carry out plate cutting of the product without fail in the shortest time.

In order to calculate the plate skew angle Θ of I, each of the points on one side of the raw material is linearly approximated among the coordinate points on the outer peripheral portion of the raw material read into the data creation computer during the teaching. The inclination angle with the table edge line is the skew angle (Θ) of the material.

Next, a method of automatically setting the cutting path will be described.

FIG. 3 is a diagram for explaining the automatic setting of the cutting path. In FIG. 3, (a), (b) and (c) show cutting by one torch (cutting jig), and (d), (e),
(F) shows cutting by two torches. First, 1
In the case of sheet taking, as shown in (a), the torch is moved from the start position along the marking line (solid line in the figure) as [1] → [2] → [3] → [4]. Further, in the case of taking two sheets, as shown in (b), one of the lengthwise directions is cut by [1] → [2], and then the torch is moved to the opposite side to [3] → [4]. ] In order. Then, the torch is moved so as to separate the test piece, and finally the middle of the product 1 and the product 2 is cut at [12]. In the case of a material with ears, the test piece is cut by moving the torch of [1] to [5] as shown in (c), then the end of the product 1 is cut by [7], and finally Intermediate product 1 and product 2 [8]
Disconnect with.

In the case of taking one sheet with two torches,
[1] → [2] → [3]
.. The torch is moved as shown, but the difference is that two torches are moved at the same time. Further, (f) is an example of a combination of an ear plate and a cutting plate, and in this case, a middle infinity (cutting-out margin) is taken in the middle.

As described above, the method of setting the cutting path route is as outside of the material as possible for the purpose of minimizing the movement amount on the surface plate due to the thermal deformation of the cutting member as described above. It is considered that the TP or the product is separated first, and the cutting line between the products is made last.

Next, the cutting process by the torch will be described in detail.

FIG. 4 is an explanatory view showing a cutting procedure in the case of cutting with two torches. In addition, the white circles in the figure indicate the product cut start points, and the black circles indicate the cut stop points.

(1) First, the bar code label that records the material number attached to the material is read, and the cutting condition data corresponding to this material number is transferred to the cutting machine. (2) Use The number of torches to be set is set (3) Reading the reference line MN (N is the origin) (4) Recognizing the plate skew angle (Θ) (5) Cutting start, between A and B torches (6) Detect the front surface of the plate front side (specifically, detect the end surfaces at points a and b from the inside of the product with the air height sensor) (7) Start preheating the B torch (about 15 seconds) (8) Start to cut on the B torch side (9) Temporarily stop the B torch when the preheating start point on the A torch side is reached (10) Start to preheat the A torch (about 15 seconds) (11) Cut both the A torch and the B torch (12) B torch cuts the product When the starting point is reached, the product is width-cut along the plate skew angle. (13) Width cutting toward the tail (TAIL) (Fig. 4)
[1]). At this time, continue to detect the tail end face with the air height sensor and make each torch height follow the flatness of the plate (14) Continue cutting until the end face on the far side of the tail is detected (up to point M) (15) A torch and Fire extinguishing B torch (16) Cross cutting on the tail side ([2] in Figure 4) (17) Machine movement (from tail to front), Cross cutting on the front side ([3] in Figure 4) (18) Machine movement (front to middle) (19) Middle cross cutting ([4] in Fig. 4) (20) End of cutting (21) Cutting data (dimensions, torch number, cutting time, etc.) Transfer to.

In this embodiment, since the plasma cutting machine and the gas cutting material machine are used for fusing, some restrictions occur due to the characteristics of the respective cutting machines. The constraint conditions for setting the cutting path route will be described below with reference to FIGS. 5, 7, 8 and 9.

When there are a plurality of products to be cut, typical cutting patterns are as shown in FIGS. 5 (a) and 5 (b). That is, there are shown a case (a) in which the cutting lines adjacent to each other have a T-shape, and a case (b) in which the cutting lines inside have a cross shape. In the case (a), 3 are shown.
The product (A, B, C) is taken, and in the case of (b), 4
You can get one (D, E, F, G) product.

First, the constraint conditions for plasma cutting will be described.

In this case, as shown in FIG. 7, a plurality of cutting means can be considered. FIG. 7 corresponds to FIG. 5A. In FIG. 7A, an example in which the product B and the product C are first cut and then the boundary with the product A is cut in the width direction is shown. Is. In FIG. 7B, the product B is cut along the inner periphery thereof, and then the boundary portion between the product A and the product C is cut.

Further, (c) of FIG. 7 is an example in which (a) and (a) are interchanged, and (d) has the same cutting direction as (c) while the cutting direction is opposite to (c). Here is an example. Although a cutting method as shown in FIG. 7E is also conceivable, it is not preferable because the cutting start point becomes the center.
However, when it is unavoidable to adopt this cutting method, a middle margin (cut-off margin) is provided, and both sides are cut.

In the cutting method of FIG. 7, the cutting method of (a) is most recommended, and the next method is (b). And, (c) is not so preferable, and (d),
(E) is a bad method. The reason for this is that the plasma arc has a large diameter as shown in FIG. 8 at the start of cutting, and cutting occurs on the product side.

Next, restrictions on cross cutting by the gas cutter will be further described with reference to FIG.

FIG. 9 shows details of the cutting portion when the gas is cut between the product A and the product B. FIGS. 9A, 9B and 9C are plan views, sectional views and cutting speed characteristics. Is shown. As shown in FIG. 5B, when the cutting line has a cross shape, cutting is performed after cutting, but when cutting is performed after cutting, the torch moves from the product A to the product B. Since a cutting width (groove) is generated when shifting to (3), insufficient preheating (that is, separation is impossible) on the product B side is caused. Therefore, as shown in (c) of FIG. 9, the torch speed is reduced (for example, 70%) at the cut portion and its vicinity, and the torch is temporarily stopped for a predetermined time.

Here, the cutting speed of 100% in (c) means
The value of the appropriate cutting speed for the thickness of the cutting material.

Next, regarding the method of cutting (running cut) from the material end face of the eared material at the time of gas cutting,
This will be described with reference to FIG.

First, as shown in FIG. 10A, the end face detection sensor 32 is moved from a certain position inside to the outside (end face side) with reference to the teaching line, and the change in the distance to the plate surface Determine the end face. Then, as shown in FIG. 10B, the torch 34 is moved from the side surface direction to the plate center direction based on the end face detection information to start cutting. At this time, as shown in (c) of FIG. 10, the torch speed is slowed down (for example, 70%) in order to obtain the residual heat time at the end face when the steel plate end face scrap is cut, and when the product is about to be cut, the torch speed is reached. To 100%. As a result, it is possible to prevent the uncut ears of the irregularly shaped ears on the gas cutting end surface outside the teaching line.

Incidentally, the above-mentioned end face detecting method is a technique which can be applied to any case of gas cutting, plasma cutting machine and the like.

[0070]

As described above, according to the present invention, when the steel plate to be cut is loaded on the table of the marking device,
With respect to the peripheral edge of the sound part of the steel plate, search the marking line until a uniform interval is formed in the width direction and the length direction, and the marking line is determined by the optimum condition obtained by this search, Since the respective coordinates of the corner portion of the marking line are determined, it is possible to carry out plate cutting of the product from the central portion of the sound portion of the azroll material while avoiding cropping and entrainment.

In the method for cutting a steel sheet according to claim 2, the cutting member (product or TP) is cut off from the outside in order, and at the same time, the common cutting line between the products is set at the end as much as possible. Because
High cutting dimension accuracy can be secured.

In the method for cutting a steel sheet according to claim 3, in the numerical control type cutting method for automatically cutting a plurality of products from the material by fusing based on the marking lines formed on the material surface, between the products to be acquired. If the cutting line of T is T-shaped or cross-shaped, plasma cutting is required for stable cutting without scratches on both sides of the product.
Since it can be set according to the gas cutting characteristics, it becomes possible to secure high cutting dimension accuracy and quality.

In the method for cutting a steel sheet according to claim 4, in the numerical control method of cutting a plurality of products from the material by fusing based on the marking lines formed on the material surface, the teaching line is used as a reference. The edge surface of the material is detected with this, and based on this detection result, the cutting torch is moved from the outer side to the inner side at a speed slower than the steady cutting speed of the product, and at the product cutting area, the steady speed is set. It is possible to automatically cut from the attached end surface.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating a nesting method for cutting a steel sheet according to the present invention.

FIG. 2 is a plan view showing a schematic configuration of a steel sheet cutting line to which a nesting method for steel sheet cutting according to the present invention is applied.

FIG. 3 is an explanatory diagram illustrating automatic setting of a cutting path according to the present invention.

FIG. 4 is an explanatory view showing a cutting procedure in the case of cutting with a two torch.

FIG. 5 is an explanatory view illustrating a method of cutting a steel sheet according to the present invention.

FIG. 6 is a flowchart showing a steel plate cutting process according to the present invention.

FIG. 7 is an explanatory diagram showing a cutting order at the time of plasma cutting in the cutting pattern of FIG.

FIG. 8 is a diagram illustrating a cutting start point and a cut stop point of the plasma cutting torch according to the present invention.

FIG. 9 is an explanatory diagram showing a cutting portion and cutting speed characteristics when performing gas cutting between two products.

FIG. 10 is an explanatory diagram illustrating a method of cutting the end surface of the material with ears.

[Explanation of symbols]

 10 Transport Table 12 Marking Device 14 Plasma & Gas Cutting Combined Machine 16 Gas Cutting Machine 18 Temporary Storage Site 20 Marking Complete Material 22 Cutting Complete Material 24 Transport Table 26 Engraver 28 Marking Device 30 Ceiling Crane 32 Edge Detection Sensor 34 Torch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahisa Yamamoto 1 Kimitsu, Kimitsu-shi, Chiba Nippon Steel Co., Ltd. Kimitsu Steel Co., Ltd. (72) Inventor Takamitsu Kobayashi 1212 Hitomi, Kimitsu, Chiba Stocks Company Kimitsu Division (72) Inventor Yoshiaki Saito Within 3-35-16 Nishikoiwa, Edogawa-ku, Tokyo Within Koike Acid Industry Co., Ltd.

Claims (4)

[Claims] 1. When the material to be cut is carried on to the table of the marking device during the work of fusing the product required from the material after rolling by gas cutting or the like, the marking line is marked on the sound part of the steel sheet. The edge is searched until uniform intervals are formed in the width direction and the length direction, and the marking line is determined when the optimum condition is obtained by this search, and each coordinate of the corner part of the marking line is determined. A nesting method for cutting a steel sheet, characterized by determining. 2. When the steel sheet to be cut is carried on the table of the marking device during the work of melting and cutting the product required from the material after rolling by gas cutting or the like, the marking line is marked on the sound part of the steel sheet. The edge is searched until uniform intervals are formed in the width direction and the length direction, and the marking line is determined when the optimum condition is obtained by this search, and each coordinate of the corner part of the marking line is determined. Based on the steel plate cutting nesting method to be determined, a cutting torch route for cutting out multiple products is automatically set for the material plate to be cut, and the steel plate is characterized by performing cutting with a numerical control method. Automatic cutting method. 3. In an automatic cutting method of a numerical control system for automatically cutting a plurality of products from the material by fusing based on the marking lines formed on the material surface, the cutting line between the products to be acquired is T when plasma cutting. Automatic cutting of steel plates characterized by setting the squareness of the plane of these products and setting stable cutting conditions that do not scratch the products when they form a letter shape or when they form a cross when gas cutting Method. 4. An automatic cutting method of a numerical control system for automatically cutting a plurality of products from the material by fusing based on marking lines formed on the material surface, wherein an end surface of the material is detected with reference to a teaching line. An automatic cutting method for steel plates with ears, characterized in that the cutting torch is moved from the outer side to the inner side at a speed slower than the steady cutting speed of the product based on the detection result, and at the steady cutting speed in the product cutting area.