JP5680982B2 - Numerical control information creation device - Google Patents

Description

  The present invention provides numerical control information for processing a region where the first rotary tool cannot enter when processing with the first rotary tool along the input shape with the second rotary tool having a smaller diameter than the first rotary tool. The present invention relates to a numerical control information creating apparatus and method for creating a computer.

  Conventionally, numerical control for recognizing a region where the first rotary tool cannot enter, that is, a so-called uncut region, and generating control information for removing the region with a second rotary tool having a smaller diameter than the first rotary tool Information creation devices are known. Such a conventional numerical control information creating apparatus will be described with reference to FIGS.

  FIG. 10 is a block diagram showing a configuration of a conventional numerical control information creation device. FIGS. 11 to 13 are diagrams showing a processing process in the numerical control information creating apparatus, and FIGS. 14A and 14B are diagrams showing a part of the processing result.

  Here, a case where the designated shape is a shape indicated by reference numeral 51 in FIG. 11 will be described as an example. In this case, the user extracts a designated shape 51 made up of an arc, a straight line, and other geometric shape elements from the component drawing, and inputs it to the shape input unit 1 of the numerical control information creation device. Further, the user can set the value of the machining allowance F left for the designated shape 51, the tool radius of the first rotary tool (first tool radius R1), the tool radius of the second rotary tool (second tool radius R2), the second The cutting width W and the like of the rotary tool are also input and set in the machining allowance setting unit 2, the first tool radius setting unit 3, the second tool radius setting unit 4, and the cutting width setting unit 9, respectively.

  The machining allowance offset processing unit 14 generates a machining shape 52 by offsetting the designated shape 51 by the machining allowance F set in the machining allowance setting unit 2 (see FIG. 11). In the first tool radius setting unit 3, a first tool radius R1 that is a tool radius of the first rotary tool is set. The tool shape offset processing unit 15 offsets the machining shape 52 generated by the machining allowance offset processing unit 14 by the first tool radius R1 set in the first tool radius setting unit 3, and obtains the movement trajectory of the tool. . Then, the tool shape offset processing unit 15 further offsets the movement locus in the reverse direction (outward direction) by a value corresponding to the first tool radius R1, thereby indicating a machining range indicating the machining range of the first rotary tool. A shape 53 (see FIG. 12) is generated.

  Unless otherwise specified, the shape offset is performed as follows. First, with respect to the line segment constituting the shape, a line segment having the same length that is translated by the offset amount in the offset direction is newly created. In addition, for the arc constituting the shape, a new arc is created by increasing or decreasing the radius by the offset amount so that the opening angle and the center position are the same and the arc moves to the offset direction. At this time, if the radius becomes 0 or less, the arc does not generate a new shape. And the shape which followed the newly created shape in order becomes an offset shape. At that time, the end points of the respective shapes become intersections of the new shapes. If the shapes are separated from each other, a new arc is formed between the shapes and the radius is offset by the offset amount and touching the front and rear shapes.

  The shape synthesis processing unit 8 synthesizes the machining shape 52 and the machining range shape 53, and obtains uncut regions 54a to 54d, which are shapes remaining by removing the machining range shape 53 from the machining shape 52 (see FIG. 13). . It can be said that the uncut regions 54 a to 54 d are a protruding range of the machining shape 52 with respect to the machining range shape 53. Subsequently, the numerical control information creating apparatus calculates numerical control information for removing the uncut regions 54a to 54d by pocket processing, which is general as region processing. Specifically, it is as follows. In the second tool radius setting unit 4, a rotary tool used for follow-up machining, that is, a second tool radius R <b> 2 that is a tool radius of the second rotary tool is set in advance. The pocket locus generating unit 16 uses the tool having the second tool radius R2 set in the second tool radius setting unit 4, and uses the inside of the uncut regions 54a to 54d obtained in the shape synthesis processing unit 8. A trajectory for performing removal processing is generated. At this time, the outer shapes of the uncut regions 54 a to 54 d are sequentially offset by the cutting width W set in the cutting width setting unit 9 to generate a tool locus. Finally, by outputting the tool trajectory generated so far to the output unit 13, the target follow-up trajectory can be obtained.

Japanese Patent Laid-Open No. 7-121219

  However, in such a conventional numerical control information generating apparatus, since the removal processing inside the uncut regions 54a to 54d is performed, there is a problem that a portion indicated by reference numeral 56 in FIG. 14A cannot be removed. In order to remove 56, a special treatment such as further defining and combining contour processing is required.

  In general, as shown in FIG. 14A, it is necessary to search for an internal position of a processed area 64 that can be regarded as having been processed by the first rotary tool, as a tool lowering position (machining start position) 58 in the initial stage of processing. Further, after descending to the tool lowering position 58, the vehicle travels toward the position 60 on the innermost offset line, but the traveling locus 62 from the tool lowering position 58 to the position 60 on the innermost offset line is long. There is also a problem that the work load becomes large due to contact between the work material and the tool half circumference over a distance.

  Further, for example, chips generated during the cutting of the uncut region 54d are generated in the uncut region 54d despite the presence of the large processed region 64 that extends in contact with the uncut regions 54a to 54d. However, since there is no discharge in the direction of the processed region 64, there is also a problem that it becomes a factor that hinders the stability of processing.

  Further, as shown in FIG. 14B, the coordinate value accuracy of the shape elements 51a and 51b constituting the designated shape 51 set in the shape input unit 1 is rough, and the shape elements 51a and 51b are broken lines forming a minute angle. Suppose there was. In this case, an uncut region 54e is generated between the machining shape 52 and the machining range shape 53 generated by offsetting the polygonal line (shape elements 51a and 51b) with the machining allowance F set in the machining allowance setting unit 2. It will be. Even if the maximum width 66 of the uncut region 54e is a thickness that should be ignored in actual machining, which is only a few μm, the conventional numerical control information creating apparatus strictly detects the uncut region as a remaining region. There was also a problem of being bad.

  The present invention has been made in view of the above-described problems of the prior art, and its purpose is not to combine a plurality of different machining definitions for removal of uncut material, and the tool lowering position at the start of machining. Is an effective machining trajectory that is always in the machined position, has good chip discharge performance during machining, and ignores uncut residue that is only a few μm thick, which should be ignored in actual machining. It is to provide a numerical control information creation device.

  The numerical control information creation device of the present invention is a numerical control information creation device that creates numerical control information for removing a remaining uncut area of a first rotary tool with a second rotary tool having a smaller diameter than the first rotary tool. A shape input unit that receives an input of a specified shape that is a shape to be machined, a tool radius setting unit that receives settings of tool radii of the first rotary tool and the second rotary tool, and an allowance remaining for the specified shape A machining allowance setting unit that accepts the setting, and a shape obtained by offsetting the specified shape to the side to be removed by the first rotary tool, with the sum of the machining allowance and the first tool radius, A value obtained by subtracting the second tool radius from the radius and offset to the side opposite to the side to be removed by the first rotary tool to calculate a first shape; and And the second tool radius The second shape calculation unit that calculates the second shape by offsetting to the side to be removed by the first rotary tool, and the shape that generates the remaining driven shape after removing the first shape from the second shape A synthesis processing unit, and a follow-up process trajectory generation unit that generates a trajectory when the second turning tool performs follow-up machining on an area left uncut by the first turning tool based on the follow-up machining shape. Features.

  In other words, the numerical control information creation device of the present invention is based on the designated shape, the first tool radius, the second tool radius, and the machining allowance, based on the outer shape of the region actually processed by the first rotary tool. A first shape offset by a small amount corresponding to the two tool radii and a second shape offset by the sum of the specified shape and the sum of the second tool radius and the offset addition amount are generated. And the shape of the range where the second shape protrudes from the first shape, that is, the follow-up machining shape which means the locus of the tool center drawn when the second rotary tool travels along the region where the first rotary tool is left uncut Is generated. Then, an offset shape group composed of a plurality of offset shapes located inside the follow-up shape is generated by sequentially applying an offset that does not target the shape element derived from the first shape to the follow-up shape. After moving along the innermost offset shape of the offset shape group as the trajectory for running the second rotary tool, it sequentially moves along the one outer offset shape, and finally along the follow-up machining shape. Output the trajectory. At that time, in order to connect the offset shapes, processing is started from the end point or the middle point of the element derived from the first shape included in each offset shape, and a route for pick-feeding is output together.

  In the present invention, since the shape that is reduced by the amount of the second tool radius is obtained as the first shape, the follow-up machining shape and the region where the first rotary tool is left uncut by the second rotary tool traveling in the inside are surely obtained. Will be removed. Further, since a slight amount is added and offset when obtaining the follow-up machining shape, it is possible to prevent detection of a narrow uncut residue that can be ignored in actual machining. In addition, since the driven shape always includes a shape element derived from the first shape, the outer periphery of the second rotary tool is processed by the first rotary tool when the center of the second rotary tool is placed on the element. Therefore, the tool lowering at the start of machining is safe without actual machining operation, and the second rotation from the position where the tool was lowered to the innermost offset shape. In the machining operation when the tool is heading, the work load is reduced because there is almost no contact between the work material and the tool half circumference. In addition, the machining operation performed by moving the center of the second rotary tool while moving to the run on the outer offset shape in order from the run on the innermost offset shape is a vast that has been machined by the first rotary tool. Since it is in a state of being opened to the side of a large area, chips generated during the machining are discharged to the vast area, and it is possible to generate an optimum trajectory for the follow-up process.

It is a block diagram which shows an example of the numerical control information creation method in this invention. It is a 1st figure of the process based on the numerical control information creation method of this invention. It is a 2nd figure of the process based on the numerical control information creation method of this invention. It is a 3rd figure of the process based on the numerical control information creation method of this invention. It is a 4th figure of the process based on the numerical control information creation method of this invention. It is a 5th figure of the process based on the numerical control information creation method of this invention. It is a 1st figure of the processing result based on the numerical control information creation method of this invention. A part of processing which constitutes the numerical control information creation method of the present invention is shown. A part of processing which constitutes the numerical control information creation method of the present invention is shown. It is a block diagram which shows an example of the conventional numerical control information creation method. It is a 1st figure of the process based on the conventional numerical control information creation method. It is a 2nd figure of the process based on the conventional numerical control information creation method. It is a 3rd figure of the process based on the conventional numerical control information creation method. It is a 1st figure which shows a part of process result based on the conventional numerical control information creation method. It is a 2nd figure which shows a part of process result based on the conventional numerical control information creation method.

  Hereinafter, a numerical control information creation device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a numerical control information creating apparatus according to an embodiment of the present invention. 2 to 6 are diagrams showing a process of creating numerical control information. FIG. 7 is a diagram showing the processing result of the numerical control information creation, and FIGS. 8 and 9 are diagrams showing a part of the processing of the numerical control information creation.

  Here, a case where the designated shape is a shape shown by 21 in FIG. 2 will be described as an example. In this case, the user extracts the designated shape 21 composed of arcs, straight lines, and other geometric shape elements from the component drawing, and inputs them to the shape input unit 1 of the numerical control information creation device. In addition, the user inputs the value of the finishing allowance F to be left for the specified shape 21 in accordance with the preset machining conditions to the allowance setting unit 2, and the cutting width at the time of follow-up machining to the cutting width setting unit 9, respectively. Set. Further, the tool radius (first tool radius) R1 of the first rotary tool is set to the first tool radius setting unit 3, and the tool radius (second tool radius) R2 of the second rotary tool (feed-up tool) is set to the second tool. Each is input to the radius setting unit 4 and set. Here, the second rotary tool is used when further removing the remaining shaving generated when the inside of the specified shape 21 is removed by the first rotary tool while leaving the set finishing allowance F. It is a tool. Therefore, a value smaller than the tool radius (first tool radius) R1 of the first rotary tool is set as the tool radius (second tool radius) R2 of the second rotary tool (R1> R2). Furthermore, in this embodiment, the offset addition amount α is also input and set to the offset addition amount setting unit 5. This offset addition amount will be described in detail later.

  When the setting of the above parameters is completed, the numerical control information creation device actually starts calculating the tool path. Here, the flow of calculation of the tool trajectory during the follow-up machining will be described in detail. As shown in FIG. 2, the first shape calculation unit 6 offsets the designated shape 21 inward by an amount (F + R1) given by the sum of the finishing allowance F and the first tool radius R1, and A tool path 22 is obtained. Subsequently, the tool trajectory 22 is offset in the opposite direction (outside) when the tool trajectory 22 is obtained by an amount (R1-R2) obtained by subtracting the second tool radius R2 from the first tool radius R1. A shape 23 is obtained.

  Next, as shown in FIG. 3, the second shape calculation unit 7 places the designated shape 21 inward by an amount (F + R2 + α) given by the sum of the finishing allowance F, the second tool radius R2, and the offset addition amount α. The second shape 24 is obtained by offsetting. As the offset addition amount α, a value slightly smaller than the minimum resolution in the position control of the numerical control device, for example, about 0.4 μm, is set and added to this offset amount. And the second shape 24 reliably cross each other. As a result, even if the deterioration of the coordinate value accuracy is accumulated through various processes, the shape synthesis is surely performed. Alternatively, when an amount of about 1 to 10 μm is set as the offset addition amount α and added to the offset amount, a remaining uncut region having a thickness of only about several μm, which should be ignored in actual machining, is not detected. In any case, the offset addition amount α is set to a small value (a value equal to or less than an allowable error) that can be ignored in actual machining.

  Next, as shown in FIGS. 4 and 5, the shape synthesizing unit 8 synthesizes the first shape 23 and the second shape 24, and excludes the first shape 23 from the second shape 24 to leave the driven shape. 25a to 25d (range shape in which the second shape 24 protrudes from the first shape 23) is obtained. Here, these follow-up shapes 25a to 25d are each composed of an element 23p (element shown by a thick line in FIG. 5) constituting the first shape 23 and an element 24p constituting the second shape 24. The In the present embodiment, among the elements constituting the driven-up shapes 25a to 25d, the element 23p constituting the first shape 23 holds the first shape information indicating that.

  Next, the offset processing unit 10 performs an operation of repeatedly performing an offset at the cutting width W set in the cutting width setting unit 9 for the follow-up processing shapes 25a to 25d. FIG. 6 is a diagram showing a state when this offset is repeated for the follow-up shape 25d. At this time, the shape element holding the first shape information, that is, the element 23p that originally forms the first shape 23 is excluded from the offset target.

  As a result, as shown in FIG. 6, on the inner side of the driven-in shape 25d, a substantially V-shaped offset line derived from the second shape and a curve derived from the first shape connecting the end points of the offset line, Thus, substantially triangular offset shapes 26a to 26d constituted by the above are obtained. Hereinafter, the plurality of offset shapes 26a to 26d are referred to as an offset shape group.

  Next, the machining start position processing unit 11 determines a start position when the center of the second rotary tool moves on the offset shape. The determination of the start position will be described with reference to FIGS. In order to make the explanation easy to understand, the curve ac, the curve fd, and the curve ig are illustrated in a shifted manner, but in actuality, these curves are all curves on the element 23p.

  When determining the start position, as shown in FIG. 8, first, among the plurality of offset shapes constituting the offset shape group, the innermost offset shape abc is specified. Subsequently, the midpoint o of the element ac having the first shape information among the elements constituting the offset shape abc is obtained. Then, the middle point o is set as a starting position for lowering the second rotary tool and starting machining.

  Alternatively, as shown in FIG. 9, the innermost offset shape abc is specified among a plurality of offset shapes constituting the offset shape group. Then, one of the intersection points of the element ac having the first shape information and the element ab or the element bc not having the first shape information among the elements ab, bc, ac constituting the offset shape abc, for example, the intersection point a And the position thereof may be set as a starting point for starting the machining by lowering the second rotary tool.

  Next, the pick feed processing unit 12 determines a path along which the tool center of the second rotary tool moves on the offset shape and the follow-up shape. In this path determination, when the processing start position processing unit 11 obtains the point o as the starting point, the offset shape def that is one outside from the offset shape abc that is the innermost, and the offset that is one further outside. A trajectory that changes to the shape ghi at the position of the middle point o (processing start point) is generated. Finally, a trajectory that moves on the outermost processing shape located on the outermost side is generated. That is, a path locus of oa-ab-bc-co-od-de-ef-fo-og-gh-hi-io ... is generated.

  Alternatively, when the processing start position processing unit 11 obtains the point a as the start point, the end point of the offset shape def is moved from the end point c of the innermost offset shape abc to the start point d of the one outer offset shape def. A trajectory that changes from f to the starting point g of the offset shape ghi that is one outside is generated. Finally, a trajectory that moves on the outermost processing shape located on the outermost side is generated. That is, a path trajectory of ab-bc-cd-de-ef-fg-gh-hi. Finally, the output unit 13 outputs the generated trajectory. In addition, although the case where the middle point o or the intersection point a is set as the machining start position is illustrated here, other points may be used as the machining start position as long as they are points on the shape element derived from the first shape.

  The locus generated by the above processing is also surely removed as shown by reference numeral 56 in FIG. 14A. Therefore, according to the present embodiment, a special treatment such as additional definition and combination of contour processing is not required to remove the portion. Moreover, since the descent position of the second rotary tool (machining start point o, point a, etc.) exists in the already machined area 27 (see FIG. 7), it is not necessary to pay attention to the tool descent position. Further, in the operation of entering the uncut region after the tool is lowered, there are almost no places where the second rotary tool comes into contact with the work material and the tool half circumference, and the processing load is small.

  Further, since the chips generated during the cutting of the uncut region are discharged to the vast processed region 27 existing in contact with the uncut region, the machining is stabilized. Further, since the detection of the uncut region 54e (see FIG. 14B) having a thickness of only a few μm that should be ignored in actual machining can be suppressed, machining efficiency is good.

  Therefore, according to the present embodiment, it is possible to generate a locus that can reliably and stably follow-up the uncut portion.

  1 shape input unit, 2 machining allowance setting unit, 3 first tool radius setting unit, 4 second tool radius setting unit, 5 offset addition amount setting unit, 6 first shape calculation unit, 7 second shape calculation unit, 8 shape synthesis Processing unit, 9 cutting width setting unit, 10 offset processing unit, 11 machining start position processing unit, 12 pick feed processing unit, 13 output unit, 14 machining allowance offset processing unit, 15 tool shape offset processing unit, 16 pocket locus generation unit, 21 Specified shape, 23 First shape, 24 Second shape, 25a to 25d Drive-up shape, 26a to 26d Offset shape, 27 Pre-processed region, 54a to 54d Uncut region

Claims (3)

A numerical control information creation device for creating numerical control information for removing a remaining uncut area in the first rotary tool with a second rotary tool having a smaller diameter than the first rotary tool,
A shape input unit that accepts input of a specified shape that is a shape to be processed;
A tool radius setting unit for receiving setting of the tool radius of the first rotary tool and the second rotary tool;
An allowance setting unit that accepts an allowance setting to be left for the specified shape;
A tool center trajectory of the first rotary tool obtained by offsetting the specified shape to the side to be removed by the first rotary tool is calculated by the sum of the machining allowance and the radius of the first rotary tool . the tool center path of the tool, further, a value obtained by subtracting the radius of the second rotary tool from the radius of the first rotating tool, the first offset to the side opposite to the side to remove processed by said first rotary tool A first shape calculation unit for calculating a shape;
A second shape calculation unit that calculates the second shape by offsetting the designated shape to the side to be removed by the first rotary tool, with the sum of the machining allowance and the radius of the second rotary tool;
A shape synthesis processing unit that generates a driven-up shape remaining by excluding the first shape from the second shape;
Based on the follow-up machining shape, an area left uncut by the first rotary tool, a trace generating unit for follow-up machining that generates a trace when the second rotary tool performs the follow-up machining,
A numerical control information creating apparatus characterized by comprising: The numerical control information creation device according to claim 1, further comprising:
An offset addition amount setting unit that receives a setting of an offset addition amount that is added as an offset amount when calculating the second shape,
The second shape calculator is configured to remove the specified shape with the first rotary tool with a value obtained by adding the offset addition amount to the sum of the machining allowance and the radius of the second rotary tool. Calculate the offset shape as the second shape,
A numerical control information creating apparatus characterized by that. The numerical control information creation device according to claim 1 or 2,
The follow-up machining trajectory generator is
A shape offset processing unit for calculating an offset shape group in which only the shape elements constituting the second shape among the follow-up processed shapes are sequentially offset inward;
Of shaped elements constituting the first shape, located between the ends of the offset shape group Urn Chi most inner offset shape, the points on the shaped element, as the start position of the processing by the second rotary tool A processing start position processing unit to be extracted;
A pick feed processing unit that generates a locus of a second rotary tool that moves along the offset shape and the follow-up shape;
A numerical control information creating apparatus comprising: