Method and System for eliminating external piercing in nc cutting of nested parts

[0001] The present invention relates to the field of cutting elements out of sheets or boards, in particular methods, devices and a computer-readable medium ensuring the improvement of cutting elements by creating the possibility of positioning or start notches between neighboring elements, as well as the efficient distribution of their remains.

BACKGROUND OF THE INVENTION [0002] Conventional metal cutting technologies are well known in the art. For example, oxy-acetylene cutting technology has been used since the early 1920s, with the technology used to direct the gas stream of a mixture of oxygen and acetylene to burn a steel plate. The hot narrow gas stream directed through the burners at high pressure actually burns the material, because when the high temperature is used and the gas fuel is used, the iron easily melts. It is a traditional and fast way of cutting iron and steel, which has been used for over a hundred years. Oxygen-acetylene cutting technology allows cutting desired and defined shapes in steel with a thickness of up to one foot. Plasma cutting technology is relatively new, it was developed around 1970, with the technology of cutting steel, steel used to make protective coats and aluminum, in which a stream of ionized gas is used to support the electric arc that ensures combustion and melting of the material. This technology allows cutting up to ten times faster than with an oxy-acetylene torch, but its range of use is limited to metals less than six inches thick, and generally less than two inches thick.

[0003] High resolution plasma cutting technology is an improvement of plasma cutting technology using torches designed to cut material sheets to a thickness of up to half an inch. This technology ensures more accurate, narrow cuts in such thinner material. Laser cutting technology is the contemporary of plasma cutting technology. In the case of laser cutting technology, a highly focused laser beam is directed at the material, which causes the material to burn or melt. In some cases the laser may have gas assist. Laser cutting technology has advantages over other technologies because it requires much less power, ensures much greater cutting accuracy, obtaining a minimum cutting width and enables cutting of a wide range of metal and non-metal materials, including steel, aluminum, wood, plastics, etc. .

[0004] US 6,359 251 B1 describes a method in which a plasma arc system is integrated into a single controller providing power control of the plasma arc system.

[0005] Waterjet cutting technology is another cutting technology developed in the seventies that uses abrasive media introduced into a very narrow high speed water jet.

[0006] Waterjet cutting technology is generally used to cut stone and ceramics, but that it can also be used to cut thin metals without heating them.

[0007] EP 1342526 A discloses another cutting technology for making edges, in which a bevel cutting method is used to reduce the cutting time and reduce the surface of the waste, in which a cutting line extending in the first direction and a cutting line extending in a different direction, which provides the ability to regulate rotation.

[0008] The terms "profile", "path" and "outline" are essentially equivalent terms that refer to a set of lines and arcs forming the periphery of a part. Paths are usually closed, and this applies to both internal and external paths. If they describe unclosed internal paths, they are called "slots". Unclosed external paths are a problem because you don't know where the item is until you close the path. Cutting shapes is sometimes called 'profiling' or 'contouring'. Strictly speaking, the path is usually the contour along which the cutting device is moved, in general NC terminology (numerical control) it is called the "tool path". The element consists of a single external profile and potentially many holes in the element, which are called internal profiles and are made of a block or sheet of material called a workpiece.

[0009] US 6,609,044 BA describes a method in which conventional software is used to create accepted NC codes in the method, thereby creating an optimized element cutting program ensuring minimizing rapid displacements. This makes it possible to reduce the time required to perform all the required cuts in the sheet material.

[0010] The term "edge start" refers to a cut that can be started directly at the edge of the plate. In fact, the puncture is only used to make the hole, which then allows cutting the edge. This is different from cutting from above, which is similar to sawing. The idea of ​​starting from the edge is to heat the edge to the required combustion or melting temperature before entering the material. This requires a certain delay at the edge. In some NC control systems, this function is available as part of standard coding, but most require programming of the machine to stand at the edge for a specified period of time until the material has been heated to such an extent that cutting can be performed. Although starting from the edge is beneficial, when using continuous cutting, a hole piercing is generally required for each element. Edge start enables cutting material twice as thick as when it is necessary to pierce the material. Another advantage is that, compared to piercing, cutting can be started almost immediately, because the entire edge of the material can at the same time be heated to the flash point. The result is no melt explosion from the pierced hole and no overheating of the take-off area to pass through the material. In the current state of the art, edge start is extremely beneficial but rarely used. In the present invention, edge start points are created automatically for all elements belonging to the group.

[0011] The term "cutting gap" refers to the radius of the hole formed by the torch. Usually it corresponds to half the width of the linear cut using a round torch. The cut gap is critical for cutting. When cutting the shape, the center of the torch must therefore be kept at least a distance equal to the "cutting gap" from the shape profile so that the cut part has the correct dimension. This shift of the desired shape to the center of the torch is known as "cut gap compensation" and is one of the most demanding functions implemented by NC control. It should also be noted that the thicker the material, the more power it needs to make the cut. As a result, the cutting diameter increases and the cutting gap increases. When using lasers and sheet metal about 0.15 mm thick, the cutting gap may be very small. For thick material (for example, 2 inch or 50 mm thick boards), it can be 4 mm, with a total cutting width of 8 mm. [0012] For each of the above cutting technologies, it is common practice to cut each element separately by creating a start hole or "piercing" adjacent to the element, and then performing cutting, i.e. separating the element from the surrounding material. Performing a puncture, however, is associated with significant costs, because cutting through the material through requires considerable energy and time. The start hole is also extremely destructive and must begin at a considerable distance from the element to avoid damage to the element, which can be associated with both its final shape and the metallurgical construction of the heat-treated area surrounding the puncture.

[0013] Generally speaking, in the field of material cutting, it is common practice to optimize the operation of the cutting tool in a manner that ensures cutting from the edge of the material. The cutting tool is rarely suitable for puncturing material, so a separate process is often used for this purpose. Traditionally, it is necessary to pierce the material to create a hole, thanks to which it is possible to use an edge cutting tool. To cut multiple items, you must create multiple burns. Each of the piercing processes is time consuming, causes material loss and damage.

[0014] There is therefore a need for a method and system that allows cutting elements or separating them from the surrounding material, without having to create individual entry holes or punctures for each element.

SUMMARY OF THE INVENTION [0015] The present invention provides a method for cutting at least two elements from a workpiece having the features set out in claim 1, a computer readable medium having the features set out in claim 8 and a device for cutting at least two elements from the workpiece having the features specified in claim 9.

[0016] Preferred embodiments of the invention are disclosed in the dependent claims.

[0017] In the present invention, a numerically controlled device and method for cutting a workpiece with a cutting tool is provided to form a block of material at least two elements having specific shapes. The method may preferably comprise the steps of: identifying each of the elements using one or more contour lines; cutting the workpiece along one of the identifying contour lines to cut one of said elements; forming at least one branch, the branch being shaped in such a way as to ensure removal of additional material and creation of limited areas, a notch or holes used for subsequent cutting without re-piercing the block of material, the obtained limited area or hole being referred to hereinafter as parts of this description; resume cutting the element along the identifying contour line until the element is cut out. Ideally, creating a start cutout does not change the external geometry of the current element in any way that causes a change in the shape of the cut element or damage to the element. The process involves moving the cutting tool to a pre-made start notch and then to an adjacent and associated identification contour line; and repeating the cutting process until all the elements that should be cut out of the sheet are cut.

[0018] A device for making a cutting opportunity in a workpiece, such as a plastic sheet or metal plate, may advantageously include a cutting tool, which includes: a head assembly comprising a cutting head, a platform or a bed on which the sheet is placed; and a programmable computer or numerical control (NC) device designed to control the position and movement of the tool relative to the platform along the programmed path; another, usually separate computer designed to generate a computer program; the program itself created and saved in a computer file; the drive assembly connected to the at least one tool and platform to move the tool relative to the platform along the programmed path, wherein after the drive unit has moved the tool to a position enabling cutting of the element from the plate or sheet, it is also moved to form a start notch located on programmed track.

[0019] The invention can advantageously be used in conjunction with a numerically controlled device for cutting out elements having specific shapes from a material block and comprising: a module identifying each of said elements using one or more contour lines, the cutting tool cutting the workpiece along one of the identifying contour lines for making one of said elements; a module designed to form at least one branch, wherein a start notch is associated with said branch, and the cutting tool cuts the workpiece along the contour line associated with the start notch; and a module designed to resume cutting the element along the identifying contour line.

BRIEF DESCRIPTION OF THE DRAWINGS [0020]

Fig. 1 shows a numerically controlled system for cutting parts according to the present invention;

Fig. 2 shows a conventional rectangular sheet or plate, with ideal shapes cut out using conventional technology;

Fig. 3 shows a commonly used conventional method for cutting elements from a sheet with minimizing the number of punched holes;

Fig. 4 shows a second method for cutting elements from a sheet;

Fig. 5a illustrates another conventional method of cutting elements from a sheet while minimizing the number of punched holes;

Fig. 5b illustrates yet another conventional method of cutting elements from a sheet while minimizing the number of punched holes;

Fig. 6a shows a first exemplary method of making cutting opportunities that complies with the principles of the invention;

Fig. 6b shows in more detail the first exemplary method of making cutting opportunities shown in Fig. 6a;

Fig. 7a shows a second exemplary method of making cutting opportunities that complies with the principles of the invention;

Fig. 7b shows a cutting opportunity made using the exemplary method of Fig. 7a;

Fig. 8 shows an example of making cutting opportunities in accordance with the principles of the invention;

Fig. 9 is a block diagram of a process for identifying part contours that is in accordance with the principles of the invention;

Fig. 10 is a block diagram of a process for identifying cutting opportunities that is in accordance with the principles of the invention; and

Fig. 11 is a block diagram of the process of performing the operations described herein.

Fig. 12 illustrates the application of the process of making cutting cutouts used to break out residual material during cutting out elements from the material, which is carried out at the place of the process.

[0021] It will be appreciated that these drawings are only intended to illustrate the concept of the invention and are not intended to define the limitations of the invention. The embodiments shown in the drawings and described in the accompanying detailed description should be considered as exemplary embodiments, and not as the only way to implement the invention. The same reference numbers were also used to designate similar elements, possibly with additional identifying marks where appropriate.

DETAILED DESCRIPTION OF THE INVENTION [0022] A numerically controlled ("NC") device or simply a device is a cutting device with a numerical control module that directs the path of the cutting tool. This device usually requires the use of a human readable list of coordinates and commands written with the letters AZ and numbers 0-10. Additional characters usually include the dot "." And a positive ("+") and negative ("-") character. Orthogonal planar axes of the machine are usually marked with the letters "X" and "Y", although in some programming languages ​​this is due to the position in the text line, where the first number is "X" and the second number is "Y". This list of displacements and activities is usually called the NC program. Numerically controlled devices are widely used in all areas of the manufacturing industry. The devices to which the present invention relates are known as machines for forming material in the form of a flat sheet or plate using an oxy-acetylene flame, plasma, laser and / or water jet. The device of Fig. 1 includes components of the present invention, such as a tool having a head assembly 130 and a cutting head or tool 125, as well as a cradle or platform 140. The production of elements from materials such as steel, aluminum, plastics involves the use of a new method and device that ensure that the cutting tool is guided along the contour cutting line, while locating sectors on the workpiece in which there is a start cutout of the material for easier carrying out process and optimization of time and materials required to produce many components. The computer used for this purpose is programmed in such a way as to ensure that the cutting notches used to produce many elements are made, which includes the steps of: identifying each of said elements using one or more contour lines; and forming at least one branch on the contour line, wherein one or more cutting start notches are associated with said branch, as will be explained in more detail below. In this innovative system, the numerical control module 110 is in the form of a dedicated computer system that operates in a manner that ensures the execution of coded instructions in accordance with the objectives of the present invention, thereby controlling the movement of the head assembly 130 along the guide attached to gate 135, i.e. in the Y + direction. The control module 110 may further control gate 135 in such a way as to ensure its movement along a guide parallel to the bed 140, i.e. in the X + direction. The combination of these movements usually allows for rectilinear motion and circular motion in the X / Y plane. The cutting head 125, for example in the form of a torch or laser, is mounted on the head assembly 130 and controlled so as to obtain cutting shapes of the elements 155, 160 from the material, e.g. from a sheet of 150 elements. The numerically controlled system 100 can be used in conjunction with any of the contactless cutting technologies discussed above.

[0023] Fig. 2 is an exemplary sheet of 150 elements, where multiple elements 155, 160, 165, 170, 175, 180, 185, 190 and 195 are visible. The elements shown here are geometric shapes that can be represented by circles, discs, squares, rectangles, etc., but in practice these elements can be very complex and may contain combinations of simpler geometric shapes. A set of elements placed on sheet metal 150, which are intended to be cut in one operation, is usually called a "group". It is important to note that the additional geometry and plate cuts resulting from the addition of inputs and outputs for burns can dramatically affect the position of elements in a group and the spacing between elements belonging to a group. For example, the size of the puncture has a significant impact on the permissible distance between elements.

[0024] Related "pierce points" 157, 162, 167, 172, 177, 182, 187, 192 and 197 are also shown. As discussed above, conventional cutting processes are primarily edge cutting techniques that require a puncture or hole to be formed. in the vicinity of the desired element. Those skilled in the art are aware that puncture points, for example point 157, must be located in such a way as to avoid damage to the desired element, since this initial hole or entry point may be much larger than the nominal "cutting gap" cutting tool. The burners usually produce a round hole whose radius is known or referred to as the "cutting gap". This is half the width of the linear cut using a round torch.

[0025] The size of the cutting gap is also a critical value of the cutting process because the cutting tool cannot be moved in a manner consistent with the exact profile or contour geometry. If it was moved in a manner consistent with the exact geometry, the resulting element would be too small or the hole would be too large. Therefore, when cutting out the shape, the center of the torch must be kept at a distance from the "cutting gap" from the shape profile, so that the cut out element is the right size. This shift of the desired shape to the center of the torch is called "cutting gap compensation" and is one of the most demanding functions performed by the numerical control module. In accordance with the principles of the present invention, the "cutting gap" will continue to refer to substantially half the width of the linear cut using the cutting tool, regardless of whether the cutting tool is in the form of a torch, laser, water jet, etc. When using lasers and sheet metal, the cutting gap may be very small, usually around 0.10 mm, while for thick materials, e.g. 2 inch or 50 mm thick sheets, the cutting gap may be 4 mm with a total cutting width of 8 mm.

[0026] In the program, the tool path is represented to obtain control of the device in such a way as to ensure that the contours of the elements are followed. Basically, it has the form of a series of lines and arcs along which the device controlled by the program will follow, with the cutting on and off as per the instructions. This path must contain all the nuances of entrances, exits, the order of elements and the direction of the cutting gap. Typically, the toolpath matches the desired element geometry, and the control module's task is to generate tool positions taking into account the width or radius of the cutting process. This is the tool path shifted.

[0027] Fig. 3 shows one exemplary method 300 for cutting multiple boards using a single pierce. In this exemplary method, which is called "bridging," elements 310, 315 and 320 are substantially identical and are disposed along a common axis. In the case of metal cutting with a torch, 330 is performed at the beginning of the cutting path. Then the torch is directed so that it follows the contour within the cut gap, which is indicated by arrows 335, 340, 345, 350, 355, 357, 360 and 365, with the purpose of separating elements 310, 315 and 320 from surrounding material. However, bridges 370 and 375 connecting elements 310, 315 and 320 are left, because the contour path, indicated by, for example, arrows 345 and 357, is not long enough to achieve complete separation of the elements from each other. Bridges 370 and 375 are then removed using a hand torch to completely separate components 310, 315 and 320. Specialists in this field will recognize that wider and darker contour lines show already cut lines, while thinner lines the contours represent path segments that have not yet been cut.

[0028] Positive bridging (cutting with bridging) has the advantages of fewer punctures, tighter grouping of elements and that, if desired, the entire group of elements can be lifted and delivered as a single object, which is then separated. However, this method has the disadvantage that the elements must be separated by hand, and their arrangement requires that all elements are cut, with the first element to be cut last. In this case, element deformation may occur due to the cumulative movement of the sheet caused by heating.

[0029] Figure 4 shows a second, less conventional method 400 for cutting multiple items using a single pierce. In this exemplary method, which the author calls "negative bridging," elements 410, 415, 420 and 425 are substantially identical and are disposed along a common axis. Again, with metal torch cutting technology, puncture 430 is performed at the beginning of the cutting path. Then the torch is directed so that it follows the contour within the cut gap, which is indicated by arrows 435 to 467, with the purpose of separating elements 410, 415, 420 and 425 from the surrounding material. In this case, the bridge connecting the elements is cut into the overlap in order to keep the bridge until the element is completely separated. For example, before proceeding to cut element 415, the torch cut path marked by arrow 437 extends to the bottom of bridge 440. For reverse cutting, which is marked by arrow 439, the cut path extends to the top of bridge 440. The cut path extends further along the top of the bridge 440 and intersects the path indicated by arrow 437, so that element 415 is separated from the surrounding material and adjacent element 410.

[0030] Negative bridging (cutting without bridging) is advantageous because it provides fewer burns per panel and tighter grouping of elements, and no additional work is needed to separate the elements after cutting. However, this method has the disadvantage that the elements are separated during the cutting process so that partially cut elements can be moved when removing adjacent elements. It is also important to note that negative bridging is not used in the cutting field, but is an extension of the bridging technique shown in Figure 3. Negative bridging is not used because it is not well understood and is difficult to automate.

[0031] Fig. 5a shows an example of a conventional chain cutting method or technique 500 in which multiple elements are cut using a single pierce point. In this example, the elements 510, 520, 530 and 540 are substantially identical and are arranged along a common axis. First, a 550 burn is made, and the torch path associated with item 510 is indicated by arrows 555, 556, 558, and 560. The intersection of path 560 and path 555 separates element 510 from the surrounding material. The torch continues cutting the material so that path 565 can reach element 520. Similar to element 510, the torch cuts element 520, which is accomplished by continuing movement along the cutting path indicated by arrows 570, 572, 574 and 575. Chain cutting is preferred because one piercing is used to cut a number of parts, and therefore a reduction in cutting time is provided by making fewer burns. It is necessary to make longer cuts that ensure the transition from one element to another, which results in loss of material and operating time of the device. Despite the fact that this technique causes waste of time and material, it is widely used in devices without numerical control and performing operations sequentially, because in this case cutting out many elements does not require the intervention of the operator.

[0032] Fig. 5b illustrates a second method for cutting multiple items using a single puncture, which is referred to herein as the "star puncture". In this method, the element 598 is separated from the surrounding material by creating a piercing point 591 and then guiding the tool according to the cutting vectors 593, 594, 595, 596. The tool is then guided along the cutting vector line 592 to the puncture point 591, possibly with the cutting tool turned off. A similar procedure is then repeated for element number 599, with the cutting tool being moved along the 597 vector line to the contour line (with at least the cutting tool cutting width subtracted), which ensures cutting along the contour line of the 599 element, after which the tool returns along 597. This provides some increase in efficiency by reusing the costly and harmful piercing and the less costly cutting process than the chain cutting of Fig. 5a, but it is still necessary to create a piercing for each star group.

[0033] Fig. 6a illustrates a method of creating cutting opportunities used for cutting multiple items, which is in accordance with the principles of the present invention and comprising the steps of: identifying each of said items using one or more contour lines; and forming at least one branch along the contour line, wherein one or more start notches are associated with the branch. In fig. 6a shows a method 600 for cutting elements from a base material, i.e. element sheets, which is in accordance with the principles of the present invention. In the presented method, puncture 602 is initiated using the methods discussed above, after which it is possible to start the process of separating the element 630 from the surrounding material, which is made using a cutting tool, e.g. a torch, making a cut along the contour lines marked with vectors or arrows 603, 604, 606 and 608. Then, at 616, the direction of movement of the torch is changed and the start cutout, hole or edge is started to be done by moving the cutting tool along the vectors or arrows 610, 612, 614. Start cutout 633 is ready when the cutting tool returns to point 616 along contour line 615, which has already been cut. Element 630 is separated by cutting along the contour lines of element 630, which are indicated by arrows 618, 620 and 622.

[0034] Those skilled in the art will recognize that when displaced along contour line 615, the cutting torch may be turned on or off. For some torches, you must turn off the torch to prevent the path from widening. This is not necessary for other torches or cutting tools. It depends on the type of torch and the physical size of the cutting opportunity, which is shown as "the width of the resumption of the cutting or cutting opportunity" and "the height of the resumption of the cutting or cutting opportunity", i.e. the dimensions of the cutting opportunity. The smaller the start cutout, the less need to turn off the torch. Depending on the cutting speed, it may also be necessary to stop the torch at the re-entry point 616 if the material has cooled.

[0035] According to the principles of the invention, each time an element is cut out, one or more of these "starting cutouts", projections or edges, which are the starting point for an adjacent element, are made. The exact shape of these start cutouts depends on the type of material, cutting process and material thickness. It can be seen that the cutting width 632 and cutting height 634 can be determined based on the cutting gap of the torch being used. It is important to note that in the current state of the art cutting of the previously cut cutting path is usually unacceptable due to the risk of cutting loss associated with cooling at 616, torch blow-in and cutting widening, as is the case with some cutting technologies such as plasma arc cutting.

[0036] Fig. 6b illustrates in more detail a cutting process in accordance with the principles of the invention shown in Fig. 6a, in which at least two elements having specific shapes are cut from the workpiece. In one embodiment, the process comprises the steps of: identifying each of said elements using one or more contour lines; cutting the workpiece along one of the identifying contour lines to form one of said elements; forming at least one branch, wherein the branch is associated with a cutting opportunity; cutting the workpiece along the contour line associated with the starting notch; and then resuming cutting the element along the identifying contour line. The method usually further comprises moving the cutting tool to the cutting opportunity and to the associated adjacent identifying contour line, followed by repeating the process. In this example, elements 640 and 645 are arranged side by side. Element 640 is defined by element lines or contour lines 750-753, and element 645 is defined by element lines or contour lines 656-658. In this case, a break point 655 is created, and the cut is made in the direction of the contour line 650. Since the cutting torch has a defined finite cutting width that is equal to twice the cutting gap, the cutting torch is positioned substantially at a distance from the desired clearance line 650, which is equal to the cutting gap width. The cutting torch is then moved along line 662 of the vector to cut out element 640 and separate it from the surrounding material. In this case, the cutting torch is moved in a clockwise direction at a known distance from each of the contour lines 651, 652, and 653, i.e. at a distance equal to the width of the cutting gap.

[0037] When the torch is moved parallel to the contour line 652, the direction of its movement along path 641, i.e. vectors 652, 654, 656, 658 shown in Fig. 6a, is changed so as to create a notch 644. In this case the size of the notch 644 is substantially comparable to twice the width of the cutting torch. The material in the cutout 644 is therefore removed by the cutting process, and not simply separated from the material.

[0038] When the cutting torch returns to its starting point along path 660, element 640 is separated from the surrounding material. The cutting tool is moved along said contour line associated with the first element at a constant speed. The cutting torch can be turned off, after which the cutting tool is moved rapidly at a second constant speed along vector 649 to the contour line of the adjacent element and to the start notch 647, and then is turned on again to begin separating the element 645 from the surrounding material. In this case, the starting edge is represented by point 647, which corresponds to the outer edge of the cut made using the cutting torch.

[0039] It may be appreciated by those skilled in the art that the creation and use of a cutting opportunity 644 is advantageous in that it eliminates the need to pierce the surrounding material to obtain the entry point used to start cutting. The process may also generate a series of cutting notches along which displacements of the working part of the cutting tool are made during the cutting process.

[0040] The size of the cutting opportunity is further large enough to prevent damage to the previously cut element by positioning the cutting torch far enough away from the element. In one aspect of the invention, the elements 640 and 645 can be arranged close to each other, at a distance equal to four times the size of the cutting gap radius, which does not pose a risk of damage to the edges of the element, as there are no puncture damage between the elements.

[0041] For the cutting operation shown in Figs. 6a and 6b, displacement along path 615 involves cutting along a path that has already been cut. For some materials or cutting operations, such as when cutting with plasma, this movement may damage the edges of the element. In fig. 7a illustrates a second aspect of creating a cutting opportunity in accordance with the principles of the invention that causes minimal damage to the item being cut. In this aspect of the invention, cutting is initiated, as described above, along center line 750 to perform cutting along line 770 of the element. At point 751, the cutting tool is moved away from the edge 770 of the element, and its movement continues along the path 754. In this way, the cutting tool is positioned far from line 770 of the element, and the cut is made along line 752, which leaves uncut material 765. The cutting tool is then moved along lines 754, 756, 758 and 760 of the path, returning to point 751, in which the cutting tool was initially moved away from the element line 770.

[0042] The cutting tool is then moved along the path line 762 to complete the cut along the line 770 of the element. It is apparent that the cutting tool is offset from the element line 770 by substantially half (1/2) the cutting width of the cutting tool, however, those skilled in the art are aware that the offset distance can be any distance and it is important that the cutting tool has returned to a position that allows cutting to continue along the desired line of the element.

[0043] Fig. 7b illustrates the end of the cutting process of Fig. 7a, where a smooth cut is performed along line 770 of the element. As it is seen, the size and shape of the cutting opportunity also need not be limited to twice the width of the cutting gap, as shown in Fig. 6b. However, the cutting opportunity can be made in such a way that the material within the cutting opportunity, which is designated by reference number 780, can be separated from the surrounding material in a manner similar to that of the manufactured items.

[0044] Fig. 8 shows an example of the application of the principles of the present invention to separate a group of elements from a single sheet 800. In this case, elements 810, 815, 820, 825, 830, 835, 840, 845 and 850 are arranged on sheet 800 using known ways. In some cases, the elements can be arranged freely, while in other cases, the elements can be arranged in a way that allows the maximum number of elements to be obtained from a sheet or workpiece. The process therefore involves identifying each element and arranging the contour lines in such a way as to maximize the number of elements on the workpiece. For example, in one aspect of the invention, the elements may be arranged to leave only a sufficient distance to form between the cutting elements. Therefore, one aspect of the invention includes determining algorithms for identifying contour lines based on the geometry of the elements produced by cutting the workpiece.

[0045] Also shown herein is one or more cutting opportunities associated with the designed elements. For example, cutting opportunity 812 is associated with element 810 and provides an entry point used to separate adjacent element 815 from surrounding material. Similarly, cutting opportunity 817 is associated with element 815 and provides an entry point used to initiate the cutting process to separate element 820 from the surrounding material. In another aspect of the invention, the cutting notches 832 and 834 are associated with the element 830. In this case, the cutting notch 832 provides the entry point used to start the cutting process to separate the element 835 from the surrounding material, while the cutting notch 834 provides the entry point used to start a cutting process to separate item 840 from the surrounding material.

[0046] The methods used herein can also provide for the generation of a series of start notches along which displacements of the cutting tool are made during machining of the part and the accompanying steps of generating one or more motion commands ensuring movement of the cutting tool along the contour line determined by the contour line processing module used by a numerically controlled device. Because each element is separated from the surrounding material, the associated cutting opportunity thus provides an entry point used to start the process of cutting out or separating the next or subsequent element. Because during the test of a cut out element the start notch can not be distinguished from a normal cut when testing the cut out part, it is possible to generate more than one start notch for the element. This, in turn, can be used if necessary to minimize empty motions between elements. Additional start cutouts can be used to cut to the edge of the plate and break off the remains of the material openwork to remove it. Here again, the marked fast displacements 870, 871, 872, 873, 874, 875, 876 and 877 should be noted, in which the numerically controlled torch receives the command to interrupt the cut and move at very high speed to the start cut-outs, where the cut begins edges, with points 812, 817, 822, 819, 832, 834, 842 and 844.

[0047] The device and the process ensuring the production of elements according to the concept of the present invention usually require the use of solutions enabling determination of tolerances between adjacent contour lines; executing one or more computer instructions to generate a sequence of commands containing motion orders, with each motion command signal indicating the desired position of the cutting tool relative to a characteristic mark or reference point such as a reference point on the workpiece or such as a place on an NC platform . as well as the location of contour line paths and branches in relation to the start notches and start notches in relation to neighboring elements; moving the cutting tool relative to the reference point in the form of a sequence of incremental motions carried out in accordance with the commands containing motion orders, where if the desired position indicated by the current motion order signal is a branch located on the programmed path, moving the tool relative to the reference point along the programmed contour line is performed until the position of the tool relative to the reference point is within the allowable distance from the start cutout, and when the position of the tool relative to the platform is within the allowable distance from the start cutout, the tool movement relative to the reference point is made in the direction of the point located on the programmed contour line outside the branch, according to the announced signal of the next move.

[0048] Fig. 9 is a block diagram of a process 900 providing for identifying and classifying outer contours or lines of elements as elements, and inner contours as holes and slots, in accordance with one aspect of the invention. The coordinates of the contour lines, startup notches and branches can be calculated using a computer-aided design (CAD) system. In the case of a numerically controlled device, the process 900 is stored on a computer-readable medium or in a computer file (collectively referred to as "computer-readable medium"), which ensures the execution of the program that implements the cutting operations described herein. In this case, the process includes a stroke that is in the form of a sequence of lines or areas forming a curve line. A closed or almost closed contour is one in which the end of the contour contacts or substantially contacts its beginning. It can be either the periphery of the element or an opening within the element. Also take into account the allowance for gaps, which are unclosed contours forming the marking of a flat element, such as inscriptions on the element. In block 905, all strokes are identified and classified as closed or unclosed. Block 910 determines whether there are unallocated strokes left. If the answer is affirmative, then in block 915 the largest unassigned element or element outline is selected.

[0049] In block 915, the largest remaining outer contour of the element is selected. In block 920, an element is identified by assigning an identification number to it. In one aspect, the item number is incremented by one relative to the last identification number. In another aspect, a temporary sequential negative element number is associated with the outlines that are within the outlines of the constraining or identified elements.

[0050] In block 925, all identified strokes and strokes that are geometrically completely contained within the selected boundary stroke, are assigned the same element number as a negative number, -npart. These are usually holes located in the selected element, but you must take into account the possibility of a very tightly filled plate with elements inside other elements. Thus, inside the closed contour there may be an external contour of another element inside the element or an opening located in such an internal part, it is even possible for an element inside the element, which in turn is inside another element. This logic is to enable the infinite internal positioning of elements, as in the case of Russian dolls inserted into one another (matryoshka), where parts are inside other parts inside other parts, etc.

[0051] In order to eliminate embedded elements and element strokes, in block 935 each identified hole is further examined to determine whether it also has completely contained strokes. If the answer is affirmative, then such strokes are removed from the current determination process as belonging to the current elements. As a result of this elimination, strokes that do not contain other strokes are simply referred to as holes in the contour limiting the element.

[0052] Processing then continues at block 945, in which the determination is made whether to check subsequent strokes with the identification number -npart. If the answer is yes, then processing continues at block 930. However, if the answer is negative, there are further elements that must be identified and processing continues at block 910. Any strokes eliminated in step 935 are then available for retesting. These strokes will be associated with elements nested inside other elements. Strokes identified as elements are no longer available, while the second largest element is identified in 915.

[0053] Once all contours have been classified and identified, the allocation process stops at block 920. At this point, each contour has a component number that is positive for the outer periphery and negative for the inner periphery of the same element. The internal contours are also identified as holes or gaps, which is of computational importance when assigning the size of the cut gap, but is otherwise not important in the invention. The total number of elements was also determined. Figure 10 is a block diagram of a process 1000 providing determination of cutting opportunities in accordance with the principles of the present invention. In this case, after defining the elements on the sheet, the outlines of the elements are analyzed in block 1010 and identified in block 1015, as described with reference to Fig. 9. The 900 process may include methods for creating contour line paths, branch points, and start notches using programs that generate arrays and matrices containing X-Y coordinates forming different cutting paths. This usually involves calculating multiple points representing the first stroke line and the next stroke line.

[0054] In block 1020, the elements are arranged in a sequence of cuts, which is done, for example, using rows and columns. In block 1025, a start point is selected for each element that is as close as possible to the previous element. For the first element, the point closest to the edge of the plate is selected. A block is placed on the screen in block 1030 to identify the selected position. In one aspect of the invention, the operator can move this marker according to his personal preferences, but it has been chosen so that it is as close as possible, on a clean stroke, far from complicated fragments and in an area where there is enough space for placing a start notch or break point.

[0055] In block 1040, the shortest distance between the selected element and adjacent elements is determined. At block 1050, a determination is made as to whether this distance is within a known small distance. If the answer is negative, then in block 1055 a determination is made whether there is a distance from the adjacent element to the previously cut element. If the answer is yes, then in block 1045 a proximal cut is created on the proximal element.

[0056] However, if the answer is negative, then at block 1060 a determination is made whether the specified spacing is too close. If the answer is affirmative, then in block 1065 the size of the notch is changed. However, if the answer is negative, then in block 1070 the determination is made whether a plate edge has been detected. If the answer is affirmative, then a disc marker is added in block 1075. Otherwise, in block 1080, the start notch is placed at the nearest point, after which the next element is selected. In block 1090, it is determined whether all elements have been selected. If the answer is negative, processing continues at block 1040 to specify at least one startup notch in the next element. [0057] In Fig. 11 there is shown a block diagram of process 1100 in which the principles of the invention implemented in the exemplary processing flow have been implemented. The course of the process creates a number of conditions for generating the cutting process that individually and together ensure the achievement of the objectives of the invention. For example, the process begins with the generation condition associated with the creation of the file 1105 containing all geometric displacements 1115 that form an element or group of elements on the plate 1110. These geometrical objects have the form of lines, arcs and points, as discussed above. The group is analyzed in block 1120 and the entry and start notches are determined in block 1130 as described above. In one aspect of the invention, block 1165 provides the ability for operators to perform interactive operations with respect to input, output, and start notches. The operator's interactive actions are useful to reduce the use of automated inverted element avoidance functions, bypass fasteners or holes in the material, as well as from the point of view of other preferences that are defined in terms of operations and go beyond the general definition of the problem. In block 1140, it is necessary to perform a geometric transformation to add and edit movements and objects, which allows you to create start cuts from the edges.

[0058] In block 1150, holes and elements are cut in order that is sufficiently well known in the prior art, and therefore there is no need to discuss this operation in detail. In block 1160, the strokes are converted to NC code. An example of this operation is shown in block 1170. The NC code is sent to the NC control module shown as block 1180, where the codes are converted into the motions of the cutting torch or cutting torches.

[0059] In the above description of the methodology according to the invention, the numerically controlled device shown in Fig. 1 includes a programmable control module 110, for example in the form of a computer, which is programmed to provide control of the movement of the cutting head in accordance with processes 900 to 1100 and along a programmed path, wherein after moving the tool 130 relative to the platform 140 by the drive unit 135 to position within the allowable range of distance from the branch located in the programmed path, the tool 130 is moved relative to the platform 140 towards the start notch located off the offshoot on the programmed path.

[0060] The method of creating start notches to start cutting from the edge includes adding device motions to the original contour, which achieves the goals of creating a start notch of sufficient size and shape to allow resumption of cutting at the edge of the material and to avoid introducing piercing returns to the original contour , while eliminating damage to the element having the right shape, as well as minimizing problems such as cutting loss, excessive metal temperature and inadvertent blowing of adjacent material. The method also allows the device to break openwork left as a result of cutting out individual elements by creating additional start cutouts intended for cutting to the edge of the plate where it is necessary, as well as ensuring fragmentation of openwork waste, which allows it to be removed. The presented method does not refer to the specific geometric shape of the start cutout, but this shape changes depending on the material and the cutting process, however, to achieve the stated goals it is sufficient to use different geometric shapes. The method of calculating the optimal location of the start notches makes it easier to break the plate by cutting to the edge of the plate made from the start notch, which makes it possible to reuse the start notches to make a cut from the start notch to the start notch, which can be used to completely break off the remaining openwork.

[0061] Figure 12 shows the resulting significant use of the cutting opportunity process that follows from the above assumptions. At the same time, when the elements are cut from the material using the start notches in such a way as to eliminate piercing if possible, it is possible to create additional start notches intended for breaking the plate. Completely breaking off residual material can result in significant savings in material handling and increase employee safety. After cutting out and removing elements, the openwork of the material must usually be broken into smaller pieces. Currently, plate breaking is in most cases carried out manually. As shown in fig. 11, the use of start notches leads in each case to a significant fragmentation of the remaining material, because the cuts connect one remaining hole to the adjacent hole, joining together all the contours. Additional, strategically placed cutouts can, however, result in even smaller pieces and more accurate breaking, especially in the area between the element and the edge of the plate. Most importantly, the use of start notches allows this operation to be carried out on site, without damaging the items to be removed. In a conventional solution, the elements must be removed before any attempt is made to break the openwork. This, in turn, usually causes the remaining openwork to move or strike it, which makes it difficult to automate the breaking process. The method of simultaneous breakage therefore has great advantages.

[0062] Fig. 12 shows the creation of a mostly vertical cutting by the board made from top to bottom, for this specific purpose it is carried out using elements 1220 and 1230 and additional cuts 1201, 1202, 1203. For this purpose, start cutout 1206, while the outline of element 1220 is then connected to the board by cut 1202. Start cutouts 1210 and 1212 are also created, while the outlines of parts 1220 and 1230 are joined using cut 1201. Finally, a cutout 1204 is created, which is used together with cut 1203 to cut to the opposite edge of the board. In this way, a full cut through the board is made using cuts 1202, 1201 and 1203 and elements 1220 and 1230, so that the board is completely broken along the vertical line visible in the drawing consisting of cuts 1202, 1206, 1220, 1210, 1201, 1212, 1230, 1204, 1203.

[0063] One embodiment of the present invention can be used to break a plate to the required degree, which is a unique and innovative way of breaking the remaining material, even when elements are still cut from the material, which is done in such a way that after cutting all items, both residues and items are ready to be removed.

[0064] In the present invention, the defined device must be able to start cutting on the raw edge of the material without performing a piercing cycle. The possibility of starting from the edge is not as such claimed in the present invention and is understandable in the present state of the art, but the basic idea of ​​the invention is that the possibility of starting from the edge is an inseparable feature of the device. In the current state of the art, most numerically controlled devices perform a traditional piercing cycle when starting cutting, which requires positioning on the entire plate. Plasma cutting devices will usually refuse to start cutting from the edge of the plate. It is required that most of the numerically controlled devices allow you to perform a start cycle from the edge, which allows you to start cutting from the raw edge and is designed to facilitate this operation. It is also expected that the NC program code will be assigned to this type of start, not to the commonly used pierce cycle that automatically accompanies cutting start.

[0065] The device shown in fig. 1 therefore includes a computer programmed so as to select at least one of many start notches together with the conditions for generating the process and to select at least one of many start notches; to select multiple start notches and to be able to reuse any start notch; that he chooses multiple start cutout positions that can be used to provide for easier accidental breakage of the fabric opening; to place contour lines in such a way that a minimum distance is sufficient to create a notch between adjacent elements; to place contour lines in such a way as to obtain the maximum number of elements on the workpiece; to generate a series of cutting notches along which said cutting tool moves during the movement of the cutting tool for machining the workpiece; to generate one or more motion commands to move said cutting tool along the contour line defined by these contour line processing modules; to move the cutting tool in accordance with said movement orders; to generate said start notches based on the calculated spacing in such a way that said start notches are spaced from the next contour line by said spacing towards said series.

[0066] Specialists in the field of material processing will realize that the calculation of the order and position of the cutting notches is carried out so as to optimize the order in which cuts are made, the positions depending on the order in which the elements are cut from the workpiece, which in turn depends on production requirements, heat dissipation, displacements caused by stress relief and production preferences.

[0067] The basic novel features of the present invention are shown, described and highlighted with reference to its illustrated embodiments, but it should be understood that in the examples and details of the disclosed devices and in their operation, various specialists may be introduced by those skilled in the art. omissions, substitutions and changes which do not result in departing from the scope of the patent claims. For example, the present invention has been disclosed with respect to sheet and plate cutting technology, which are usually made of metals, but those skilled in the art will recognize that the present invention can be used for many materials and devices. All flat materials have essentially the same problem, from cutting a pile of material for clothes and furniture to cutting leather for shoes. The described technology is most useful in very large metalworking plants (steel and aluminum), but it can also be used for wood, concrete, marble, glass, ceramics, mica, fiberglass plates used to produce printed circuits, and even for cutting out individual elements from a silicon wafer. For any flat material cutting process, the problem is essentially that the material piercing must usually be performed using a tool designed for optimal edge cutting and not for piercing, for example with ordinary shears. However, thanks to the present invention, edge cutting can be a normal and defined plate cutting operation, by adding process generation conditions such as a mathematical formula and appropriate algorithms to create geometric groups, change geometry to create the described start cutouts that allow starting from edges and cutting whole group of elements or pants without piercing.