JPH09216127A - Tool path generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct highly efficient processing by generating the scanning path of a processing tool with an area where an area removed by processing operation for the next stage subtracted from a finishing stock area to be left at the time of coarse processing for a particular stage serving as a finish processing area for a particular stage. SOLUTION: The first stage cross-section contour A2 which is offset in Z direction by the length of finishing stock in Z-direction is outputted and stored. Of the finish processing area which is offset from a target processing area at the time of the output of the first stage coarse processing area, the area from which the second stage processing area is removed is outputted as the finish processing area. A plan sectional view of the finish processing area is C. The second stage coarse processing area B2 is outputted. The second stage finish processing area is outputted, however, a plan sectional view of the second finish processing area is B because the (N+1)th stage (3rd stage) processing area is not present.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool path generation device for generating a tool path, and for example, a tool path generation device for controlling a processing machine that performs removal machining by moving a tool according to the tool path. is there.

[0002]

2. Description of the Related Art FIG. 14 shows, for example, a publication {applied mechanical engineering.
It is a block diagram of a general tool path generation device used for machining shown in the September 1993 issue, pages 48 to 49}.
In the figure, 100 is a machining area generation unit that obtains an area for generating a tool path, and 101 is a tool path generation unit that obtains a tool path for scanning a tool for machining the machining area obtained by the machining area generation unit. Is. Conventionally, in machining such as cutting and electric discharge contouring, rough machining is usually performed first with a high machining speed but low accuracy, and then finish machining with high machining accuracy but slow machining speed is performed. FIG. 15 is an explanatory view showing a perspective view showing a target multistage machining shape in machining and a cross-sectional view taken along the line II ′ in this perspective view, and FIG. 16 is an explanation explaining a machining region by a tool path generation device. 16 (a) is a plan view showing the cross-sectional shape of the first step shown by the line P in FIG. 15, and FIG. 16 (b) is Q
FIG. 16C is a plan view showing the cross-sectional shape of the second step indicated by the line.
[FIG. 4] is a plan view showing an originally required finish-processed surface shape of the first step.

FIG. 17 is a flow chart showing the operation of a conventional tool path generating device. In step st1, the three-dimensional shape data of the target machining shape is read, in step st2 the finishing allowance of each stage is set, and in step st3
Calculate and output the cross-sectional shape of each step. Step st4
Then, the processing step order (N) is set to the initial value 1, and step st
Offsetting the finishing allowance in the X, Y, and Z directions inside the target machining shape based on the cross-sectional shape of each step output in 3
The rough machining area of the step (for example, A2 in FIG. 16) is output. In step st5, the finish machining area offset from the target machining shape is output as the first stage rough machining area when the first stage rough machining area is output. A plan sectional view of this finishing region is A in FIG. Steps
At t6, the repetition of the above steps is instructed, N = 2 is set, and the process proceeds to the output of the machining area of the second stage. Second step s
At t4, B2 of FIG. 16 is output as the rough machining area of the second stage, and at step st5, B of FIG. 16 is output as the finishing machining area of the second stage. That is, in the conventional tool path generation device, the area to be machined in rough machining and the area to be machined in finishing are the same except for the difference in finishing allowance.

Further, since the larger the diameter of the tool is, the faster the machining speed is, it is desirable to carry out the machining using a tool having the largest diameter in view of the machining speed. However, depending on the shape, when a tool having a large diameter is used, unprocessed parts may be left at corners and the like. In such a case, there are two methods for removing the residual material. 1
One is a method in which a tool that does not leave a machining residue is used in advance, and the second is a method in which a tool path with a small tool is generated for a portion left with a large tool. The latter method will be described with reference to the drawings.

18 and 19 are explanatory views for explaining a processing state using conventional large and small tools (electrodes).
FIG. 18A is a machining region in which a target pocket machining shape is shown by dots in a plan view seen from above, and FIG. 18B is a cross-sectional view showing a cross section of two types of machining electrodes a11 and a12 having different diameters. It is a figure. 19 (a) is a schematic view schematically showing the trajectory of the electrode when processed with the basic electrode a11, FIG. 19 (b) is a plan view showing a residual region when processed with the basic electrode a11, and FIG. FIG. 8B is a plan view showing an area set to include the above-mentioned leftover area in order to perform processing with the electrode a12 having a tool diameter smaller than that of the basic electrode a11 again for such leftover area. Note that, conventionally, the user sets the machining area on the electrode a12 after confirming the unmachined area after machining, but the user preliminarily sets the machining area on the portion where the unmachined area is considered in consideration of the tool radius. May be set.

[0006]

Problems to be Solved by the Invention FIGS. 20 (a) to 20 (d)
FIG. 16 is a process diagram showing, in the order of processes, machining by the above-described conventional tool path generation device when machining the multi-stage machining shape shown in FIG. 15. That is, first, roughing is performed on the first stage and then finishing is performed, and then roughing on the second stage is performed and then finishing is performed on the second stage. FIG. 21A is an explanatory view showing the setting of the processing area when the above-described conventional processing is performed, and FIG. 21B is an explanatory view showing the setting of the target processing area. FIG. 21 (a)
As is clear from a comparison between (b) and (b), when processing is performed as in the prior art, the portion indicated by the arrow in FIG. 21 (a) is a portion that is scraped by roughing processing, so there is no need for finishing processing. Should be. In other words, since the conventional tool path generator determines rough machining and finishing machining as described above,
There is a problem that a tool path for finishing is generated up to a useless part. In particular, in the case of electric discharge contour machining in which machining is performed by scanning a cylindrical electrode, the machining speed and the moving speed in the finishing machining are very slow, which causes a problem of a large waste of machining time.

Further, in the conventional tool path generation device using large and small tools, there is a problem that the user has to bother to set the remaining portion. Also, usually
Since the leftover portion is set to be large in consideration of safety, an extra area is to be machined by a small tool having a low machining speed or moving speed, and this dead time becomes very large.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a tool path generating device for performing efficient machining with less waste of machining time.

[0009]

A first tool path generating device according to the present invention provides a scanning path of a processing tool for a processing machine which scans the processing shape having a plurality of steps by processing the processing tool. In the tool path generation device for generating a specific stage, when the machining of a specific stage is performed, a region obtained by subtracting the region removed by the machining of the next stage from the finishing allowance region left at the time of rough machining of the stage, The scanning path of the machining tool is generated as the finishing machining area.

A second tool path generating device according to the present invention is
A difference area between a target machining shape and a region machined by the first machining tool in a tool path generation device that generates a scanning path of the machining tool for a machining machine that scans the machining tool to machine the target machining shape. Is defined as a region left unprocessed by the machining tool, and the region left unmachined is machined by a second tool having a smaller diameter than the first machining tool.

A third tool path generating device according to the present invention is
In the second tool path generating device, the machining tool is a cylindrical electrode tool for electric discharge contour machining, and the shape of the remaining region is calculated with the inner diameter of the cylindrical electrode tool as the tool diameter.

A fourth tool path generating device according to the present invention is
In the second tool path generation device described above, the shape of the remaining region is calculated by estimating the tool diameter as large as the discharge gap as the diameter of the machining tool.

A fifth tool path generating device according to the present invention is
In the second tool path generating device, a first machining area width including a remaining area of the first machining tool is set, and the first machining area width is set to the machining area width of the second machining tool. A machining tool path for sequentially offsetting and machining is generated.

A sixth tool path generating device according to the present invention is
In the fifth tool path generation device, the first processing region width is set based on the diameter of the first processing tool.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. FIG. 1 is a block diagram of a general tool path generation device. In the figure, reference numeral 100 denotes a processing area generation unit that obtains an area for tool path generation, and a shape is generated from processing shape information that is normally input, and is a processing target. This is a part for extracting the area shape. Reference numeral 101 in the drawing is a tool path generation unit that obtains a tool path for the processing area obtained by the processing area generation unit, and processes the area generated by the processing area generation unit according to the input processing conditions, finishing allowance, and electrode data. This is a part for generating a tool path for performing.

FIG. 2 is a block diagram showing the operation of the machining area generator 100 associated with the tool path generator according to the first embodiment of the present invention. In the figure, 1 is a three-dimensional shape input unit for inputting a three-dimensional shape model, 2 is a cross-sectional shape output unit for each stage that outputs a two-dimensional cross-sectional shape in an arbitrary stage from the input three-dimensional shape, and 3 is The cross-sectional shape storage unit of each stage, which stores the cross-sectional shape of each step output by the cross-sectional shape output unit 2, inputs the finishing allowance in the XY direction and the finishing allowance in the Z direction of each shape in any step. Finishing cost input section, 5
Is a finish allowance storage unit for storing the finish allowance of each stage input by the finish allowance input unit 2 for inputting the finish allowance of each shape in an arbitrary stage, and 6 is a finish allowance offset at the time of rough machining of each stage Finishing allowance offset shape output unit for outputting the shape; 8 is a finishing allowance offset shape storage unit for storing the finish-offset length offset shape of each stage outputted by the finishing allowance offset shape output unit 6 , 9a is a rough machining area output unit for each stage that outputs the rough machining area for each stage from the shape stored in the finish allowance offset shape storage unit, and 9b is a finish machining area output unit for obtaining the finish machining area. 7 is a finishing allowance offset shape storage unit 8 of each stage
And a finishing area roughing area output section 9a, 9b at each stage.

Next, the operation of the machining area generator 100 will be described. Here, FIG. 3 is a flowchart showing the flow of processing in the processing area generation unit 100. The flow of processing will be specifically described assuming that the shape shown in FIG. 15 is a target processing shape obtained by processing a rectangular parallelepiped work. That is, in step st1, the three-dimensional shape is first read in, and in step st2, the finishing allowance in the XY direction of each stage at the height set in step st1 is set. In step st3, the shape of the cross section at each step is calculated from the three-dimensional shape read in step st1, and is output and stored. When the target processed shape is FIG. 15, two shapes, that is, the first step sectional shape A and the second step sectional shape B shown in FIG. 16 are obtained. In step st4,
The machining step sequence (N) is set to an initial value of 1, and the sectional shape of each step output and stored in step st3 is offset in the XY direction by the length of the finishing allowance in the XY direction, and finished in the Z direction. The sectional shape A2 (FIG. 16) of the first step, which is offset in the Z direction by the length of the margin, is output and stored. The shape generated in step st4 becomes a target area in which a tool path for rough machining is generated. In step st5,
Of the finishing machining area offset from the target machining area at the time of outputting the first-stage rough machining area, the area excluding the second-stage machining area is output as the finishing machining area. A plan sectional view of this finishing region is C shown in FIG.
At step st6, the repetition of the above steps is instructed, and N
= 2 and proceed to the output of the processing area in the second stage. In the second step st4, the rough machining area B2 of the second stage is output. In step st5, the finishing machining area of the second stage is output, but since there is no N + 1th stage (third stage) machining area here, the plan sectional view of the finishing machining area of the second stage is shown in FIG. It becomes B of. XY of finishing area
The contour line in the direction may be inside or outside the finishing allowance in the XY directions depending on the processing order.

In the present embodiment, there is no useless tool path, so that there is an effect that the machining time is shortened. Particularly, in the case of the electric discharge contour machining, the machining speed and the moving speed of the finishing machining are slow, so that the effect is very large.

The tool path generation unit 101 takes into consideration the processing width of the tool used in each process for each of the rough machining and finish machining areas output by the machining area generator 100. Is calculated and output. The form of the machining path can be selected from a zigzag type, a turning type, a multiple closed loop type, and the like.

Embodiment 2 FIG. 4 is a configuration diagram of a tool path generation device according to the second embodiment of the present invention, and is 100 in the figure.
Is a machining area generation unit for obtaining an area for tool path generation,
Reference numeral 101 is a tool path generation unit that obtains a tool path for the processing area obtained by the processing area generation unit, and reference numeral 102 is a leftover area extraction unit.

5 (a) to 5 (d) and 6 (a) to 6 (a).
FIG. 7E is an explanatory diagram showing the operation of the remaining area extracting unit 102 of the present invention, and FIG. 7 is a flowchart showing the processing flow of the remaining area extracting unit 102. First, a closed loop that sequentially offsets the tool path of the first step using the basic tool a11 {Fig. 6 (d)} for the initial shape a1 {Fig. 5 (a)} that is the target machining shape by the machining width of the tool A tool path (machining path) a2 of the mold is generated by the tool path generation unit {FIG. 5 (b): step st1}. Step st1
The machining tool path a3 that is actually machined and the moving tool path a4 for the tool to simply move between the machining tool paths are divided from the tool path generated in step {FIG. 5 (c): step st2}. Since the machining tool path a3 is a tool path obtained by offsetting the contour of the machining shape, it has a closed loop shape. Next, a region a6 to be machined while the basic tool is moving along each machining tool path a5 is calculated {FIG. 5 (d): step st3}. The shape a7 obtained by subtracting the machining area a6 from the initial shape a1 which is the first machining area calculation target becomes the machining area calculation target shape in the next machining tool path a8 {FIG. 6 (a): step st
4}. As a result of repeating this process for all the machining tool paths in sequence, the obtained shape is the remaining area a9 {FIG. 6 (b): step st6}. In step st7, with respect to the residual shape a9 obtained in step st6, the tool path of the second process using the residual machining tool a12 {FIG. 6 (e)} is sequentially closed loop type for each machining width of the tool. Is generated as the tool path a10 of {Fig. 6 (c)}.

In the second embodiment, when the unmachined area is obtained, the difference between the machining areas is calculated every time the machining tool path is generated. First, the machining areas for all tool paths are calculated. In addition, finally, the unprocessed region may be obtained by performing a difference calculation between the target processed shape and the rough processed region. According to the present invention, the operation of setting the remaining portion by the user is automated, so the operation is simple. In addition, it is not necessary to set a large remaining portion in consideration of safety, so that unnecessary processing is eliminated and processing time is shortened.

Embodiment 3 FIG. In the case of electric discharge contour machining, since the tool electrode is consumed and deformed during machining, it is necessary to use a virtual tool shape that allows for the deformation. FIG. 8 is a side view of a tool used for electric discharge contour machining,
(A) is a side view of the tool before it is used for electric discharge contour machining,
(B) is a side view after use. That is, since tool consumption occurs in the same machining, when a cylindrical tool is used, the tool has a truncated cone shape as shown in the figure, so the machining depth between the center and end of the tool is different. Will end up. In order to make the machining area after machining on a flat portion, it is necessary to extract the unremained area with a tool whose inner diameter is the outer shape. That is, in the processing area calculation in step st2 of FIG.
The machining area is calculated using the tool shape after use instead of the actual tool shape. In addition, since the electric discharge contour machining is non-contact machining, the workpiece is excessively machined by the discharge gap.Therefore, the machining area is calculated using the virtual electrode shape with a large dimension for the discharge gap. By doing so, higher processing accuracy can be obtained. According to this embodiment, in the electric discharge contour machining, there is an effect that the leftover region is set in consideration of the electric discharge gap and the tool shape, and a tool path with no waste and high accuracy is generated.

Embodiment 4 FIG. 9 is a configuration diagram of a tool path generation device according to the fourth embodiment of the present invention, in which 100 is a machining area generation unit for obtaining an area for tool path generation, 101
Is a tool path generation unit that obtains a tool path for the processing area obtained by the processing area generation unit, and 103 is a remaining area tool path generation unit. FIG. 10 is a flowchart showing the flow of processing, which is shown in FIGS.
(C) is an explanatory view showing a remaining area machining tool path generation method, and particularly illustrates the tool path generation method for the island portion.
That is, FIG. 11A shows a portion to be set as a target processing area (point portion in the figure), b2 is an island shape, and FIG. 11B is an enlarged view of the island shape. Usually, the residual material is left behind by a basic tool, for example, around an island for pocketing or a contour portion. Therefore, in the present embodiment,
The machining tool path generation width b3 for the remaining area is input in advance for such a place.

In step st1 of FIG. 10, the island shape b2, which is a non-machined portion included in the target machined shape.
Ask for. At step st2, for the island shape b2,
A region b3 in which the offset tool path around the island is generated is calculated. Further, the contour shape b4 is obtained for the island shape b2. An island contour shape b4 corresponding to the tool path generation area b3
The shape b6 offset by b5 described below is calculated. The value of the offset distance b5 is the machining allowance b
7. When the radius of the remaining area machining tool is b8, the tool path pitch is b9, and the tool path count is b10 (variable), b5 = b9 * b10 + b7 + b8.
Among these parameters, b7, b8, and b9 are preset values, and the tool path count b1
The upper limit of 0 is set to the maximum value at which the offset shape b6 does not exceed the tool path generation width b3. An example of the offset tool path obtained as described above is shown in FIG. Count b10
Offset tool path (tool center locus) when is 0 is b
The tool path when 60 and b10 are 1 is shown by b61. A shape group obtained by offsetting the island contour shape b4 by the offset amount b5 is set as b6, and becomes a machining tool path b12 of an island-offset tool path. If there is a region b13 that is not machined in step st3, the machining tool path b
The tool path b that checks the interference between each of the tool path shapes 12 and the area b13 and avoids the interference part b14
Correct to 15. In step st4, a connecting tool path b16 (not shown) that connects the offset tool path b15 corrected by the interference check is added to generate an island around offset tool path b17 (not shown). Step st
In 5, when a plurality of island shapes b2 are present, a tool path b18 including a tool path that connects the respective island-offset tool paths b17 formed by sequentially repeating the process
(Not shown).

According to the present embodiment, the remaining region machining tool route is automatically determined only by setting the route generation width b3 for the remaining region machining tool, so that the operation is simplified. Further, since the tool path is created by using the island contour shape, it is possible to avoid setting the unprocessed machining area unnecessarily large and to shorten the processing time.

Embodiment 5 FIG. In the fourth embodiment, b3 is input, but it is clear that what is left behind is at least the radius of the tool and not more than the diameter, so the value is automatically set. According to the present embodiment, it is not necessary to set the margin for leaving by the leftover tool, so that there is an effect that the user's operation becomes easier.

Embodiment 6 FIG. FIGS. 13A to 13C are explanatory views for explaining machining by the tool path generation device according to the sixth embodiment of this invention. When the final machining shape as shown in FIG. 13A is to be machined, the area to be machined by the basic tool a11 is shown in FIG.
The region processed in 12 is shown in FIG. FIG.
(B) is not the final shape shown in FIG. 13 (a) in advance, but b
This is an area that is offset by 3 widths toward the inside of the processing area and made smaller. FIG. 13C shows an unprocessed area corresponding to the offset in FIG. 13B. From the above, the basic tool a1
1 and the area to be machined by the unmachined area machining tool a12 do not overlap, and unnecessary machining is not required. Further, the area width of FIG. 13C may be slightly larger than b3 for safety. According to the present embodiment, since the machining area of the basic tool is reduced for the island shape and the contour shape that may normally cause a residual material, the same portion is machined redundantly by the basic tool and the residual area processing tool. There is no need to do it. In particular, in the case of electric discharge contour machining, the machining speed of the remaining area machining tool is very slow, so that the effect is great.

The above-described embodiments are more effective when used in combination.

[0030]

According to the first tool path generating device of the present invention, the scanning path of the processing tool is generated for the processing machine which scans the processing shape having a plurality of steps by scanning the processing tool. In the tool path generating device, when machining a specific step, the area obtained by subtracting the area removed by the machining of the next step from the finishing allowance area left during rough machining of the step is the finishing machining area of the specific step. As described above, by generating the scanning path of the processing tool, there is an effect that the processing time is reduced and efficient processing can be performed.

According to the second tool path generating device of the present invention, in the tool path generating device for generating the scanning path of the processing tool for the processing machine which scans the processing tool to process the target processing shape, A difference region between the machining shape and a region machined by the first machining tool is defined as a residual region by the machining tool, and machining is performed by a second tool having a smaller diameter than the first machining tool with respect to the residual region. As a result, there is an effect that the processing time is reduced and efficient processing can be performed.

According to the third tool path generating device of the present invention, in the second tool path generating device, the machining tool is a discharge contour machining cylindrical electrode tool, and the inner diameter of the cylindrical electrode tool is the tool diameter. As a result, by calculating the shape of the remaining area, there is an effect that the remaining area can be appropriately set.

According to the fourth tool path generating device of the present invention, in the second tool path generating device, the diameter of the machining tool is estimated to be larger by the discharge gap, and the shape of the leftover region is calculated. By calculating
There is an effect that the processing time is less wasted, the processing is efficient, and the processing can be performed with high accuracy.

According to the fifth tool path generating device of the present invention, in the second tool path generating device, the first machining area width including the unmachined area by the first machining tool is set, It is said that the first machining region width is sequentially offset by the machining region width of the second machining tool to generate a machining tool path for machining, thereby enabling efficient machining with less waste of machining time. effective.

According to the sixth tool path generating apparatus of the present invention, in the fifth tool path generating apparatus, the first machining area width is set based on the diameter of the first machining tool. Therefore, it is possible to easily perform efficient machining with less waste of machining time.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a general tool path generation device.

FIG. 2 is a block diagram showing an operation of a machining area generation unit related to the tool path generation device according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a flow of processing in a machining area generation unit related to the tool path generation device according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram of a tool path generation device according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing an operation of a remaining area extraction unit related to the tool path generation device according to the second embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an operation of a remaining area extraction unit related to the tool path generation device according to the second embodiment of the present invention.

FIG. 7 is a flowchart showing a processing flow of a remaining area extraction unit related to the tool path generation device according to the second embodiment of the present invention.

FIG. 8 is an explanatory side view of a tool used for electric discharge contour machining according to the tool path generation device of the third embodiment of the present invention.

FIG. 9 is a configuration diagram of a tool path generation device according to a fourth embodiment of the present invention.

FIG. 10 is a flowchart showing a processing flow of a leftover machining tool path generation unit according to the fourth embodiment of the present invention.

FIG. 11 is an explanatory diagram illustrating an operation of a leftover machining tool path generation unit according to the fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram illustrating an operation of a leftover machining tool path generation unit according to the fourth embodiment of the present invention.

FIG. 13 is an explanatory diagram illustrating machining performed by the tool path generation device according to the sixth embodiment of this invention.

FIG. 14 is a configuration diagram of a general tool path generation device.

FIG. 15 is an explanatory diagram showing a multistage processed shape to be obtained by processing.

FIG. 16 is an explanatory diagram illustrating a machining area by the tool path generation device.

FIG. 17 is a flowchart showing the operation of a conventional tool path generation device.

FIG. 18 is an explanatory diagram illustrating a processing state using conventional large and small tools.

FIG. 19 is an explanatory diagram illustrating a processing state using conventional large and small tools.

FIG. 20 is a process diagram showing the processing by a conventional tool path generation device in process order.

FIG. 21 is an explanatory diagram illustrating a processing region.

[Explanation of symbols]

7 Processing Area Extraction Unit, 102 Leftover Area Extraction Unit, 1
03 Leftover area Machining tool path generation unit, a1 Target machining shape, a7 Leftover area.

Claims (6)

[Claims] 1. A tool path generation device for generating a scanning path of a machining tool for a machining machine for scanning a machining shape having a plurality of steps by machining the machining tool when machining a specific step. A tool path generation device for generating a scanning path of a machining tool as a finishing processing area of the specific step, an area obtained by subtracting an area removed by the processing of the next step from a finishing allowance area left at the time of rough processing of the step. 2. A target machined shape and a first machined tool are machined in a tool path generator that generates a scanning path of the machined tool for a machine that scans the machined tool to machine the target machined shape. The difference area from the area is set as the remaining area by the machining tool, and the first area is set to the remaining area.
A tool path generation device that processes with a second tool that has a smaller diameter than the processing tool. 3. The machining tool according to claim 2, wherein the machining tool is a cylindrical electrode tool for electric discharge contour machining, and the shape of the remaining region is calculated with the inner diameter of the cylindrical electrode tool as the tool diameter. Tool path generation device. 4. The tool path generation device according to claim 2, wherein the shape of the remaining region is calculated by estimating the tool diameter as large as the discharge gap as the diameter of the machining tool. 5. The machine tool according to claim 2, wherein a first machining area width including a residual area of the first machining tool is set, and the first machining area width is set to the second machining tool. A tool path generation device for generating a processing tool path for sequentially processing by offsetting only the processing region width. 6. The tool path generating device according to claim 5, wherein the first machining area width is set based on a diameter of the first machining tool.