JP2006043858A - Cutting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting method, preventing vibration of a tool during cutting, preventing a defective of a cutting edge, easily controlling the cutting work, and improving the working efficiency and the working accuracy. <P>SOLUTION: This cutting method includes: a first working process for cutting a shape 20 of a recessed groove part 2 using a first tool 10; a second working process of repeating the operation of moving forward a second tool 11 in the axial direction to a working remaining part 21 of the first working process to perform cutting, and moving backward the same, again moving the second tool in the axial direction to perform cutting, and moving backward the same to form a groove part 22, and cutting and removing the working remainder; and a third working process of repeating the operation of moving forward the tool 11 to the working remainder of the second working process mainly in the axial direction to perform cutting, moving backward the same, moving the tool 11 by a predetermined amount D2 along the recessed groove part, again moving forward the tool 11 mainly in the axial direction to perform cutting, and moving backward the same to cut and remove the working remainder. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cutting method for a mold or the like, and in particular, mainly a thrusting operation in which a tool is moved in the axial direction for cutting, and the time required for cutting can be shortened to improve the processing efficiency, and high accuracy. The present invention relates to a cutting method capable of chamfering.

  Conventionally, when a stepped portion 50 having an inclined surface is formed on a metal material used in a mold or the like, first, a tool 51 such as a large-diameter end mill is first used along the inclined surface 52 as shown in FIG. 10a. When it is necessary to cut the remaining processing portion (fillet) 53 of the rounded portion of the joint portion between the side portion and the bottom portion of the cutting surface, a tool 54 such as a small-diameter end mill is used as shown in FIG. The fillet portion is removed. In this cutting process, the tools 51 and 54 are moved along the stepped portion 50 in the radial direction perpendicular to the axial direction for cutting, and the horizontal running process such as the contour process and the mode process was mainly performed. .

  Further, as shown in FIG. 10c, when a concave portion 55 such as a V-groove composed of inclined surfaces on both sides is formed on a metal material, it hits the inclined surface 56 of the V-groove using a tool 51 such as a large-diameter end mill. Or slightly above the inclined surface 56. Next, as shown in FIG. 10d, when it is necessary to cut and remove the processing remaining portion 57 at the lower end, the bottom portion of the V groove is cut to a desired shape using a small diameter tool 54. Also in this cutting process, the tools 51 and 54 are moved and cut along the radial direction orthogonal to the axial direction, that is, the extending direction of the recessed part 55, and the transverse running process such as the contour process or the mode process is performed. Was the subject.

  Further, in the conventional die cutting method described in Patent Document 1, a milling tool is protruded and moved in the direction of its rotation axis in order to form a die surface having a curved outline in at least one direction with respect to the die. In the die cutting method, in which the piercing to be cut is sequentially repeated in one direction of the dies, the milling tool is moved to the end of the piercing process to the contour of the die surface at the stroke end of the piercing. It is characterized by moving along the diagonally downward along the cutting.

JP-A-8-243827

  By the way, in the cutting method shown in FIG. 10 described above, since the radius of the recess of the target finish shape is small, the tool used for cutting has a small diameter and a long tool length. In addition, since the tool has a small diameter and a long tool length, in the conventional machining method that mainly moves laterally, which moves the tool in the horizontal direction, the tool bends during machining due to insufficient rigidity of the tool, For this reason, the feed rate cannot be increased, and the machining efficiency and machining accuracy are reduced. In addition, vibrations occur during machining due to the bending of the tool, resulting in a cutting tool defect.

  In the cutting method described in Patent Document 1, the milling tool is moved obliquely downward along the contour of the die surface to the cutting position at the stroke end of the punching process and cuts it. Control is complicated, and in the case of program control, there is a problem that it takes time to create a program. Also, the protruding direction of the milling tool that forms the part relief part and the parting surface is different from the protruding direction of the ball end mill and flat end mill that forms the mold surface, hole part and edge part, and the cutting process is complicated. There was a problem.

  The present invention has been made in view of such problems, and the object of the present invention is that the main component of the machining reaction force acting on the tool during the cutting process is the tool axis direction. It is an object of the present invention to provide a cutting method capable of reducing the machining reaction force acting in the radial direction of the tool and preventing the tool from vibrating and preventing the cutting tool from being lost. It is another object of the present invention to provide a cutting method that can easily control the cutting process and can improve the processing efficiency and the processing accuracy.

  In order to achieve the above object, a first aspect of the cutting method according to the present invention includes a first machining step for cutting a rough shape of a concave portion or a stepped portion and a machining remaining portion of the first machining step. A second machining step, wherein the second machining step advances the tool in the axial direction with respect to the machining remainder of the first machining step, cuts the tool, and then retracts the tool. Is moved by a predetermined amount in the radial direction, the tool is advanced again in the axial direction, cut and then retreated, and the remaining machining is removed by cutting. The tool is moved in the axial direction, that is, cutting is performed by a thrusting operation, and then the tool is moved in the radial direction and the thrusting operation is repeated to perform a groove-shaped cutting process, and the remaining machining portion of the first processing step is removed.

  The cutting method of the present invention configured as described above performs a first process for forming a rough shape of a recess or a stepped part using a tool such as a milling cutter or an end mill, and a process left by the first process. The tool is advanced with respect to the remaining portion in the axial direction for cutting, and the tool is retracted to move in a free state to move in a radial direction along the extending direction of the recess or stepped portion. Then, the tool is advanced again in the axial direction at the moved position, cut and then retracted, and this operation is repeated to form a groove along the extending direction of the recess or stepped portion. In this way, in the second machining step, the tool is cut by moving in the axial direction, that is, by a pushing operation, so that no radial reaction force perpendicular to the axial direction is generated in the tool during machining, and the vibration of the tool is suppressed. As a result, the processing efficiency can be increased and the processing accuracy can be increased. Moreover, control is easy and cutting can be performed easily.

  A second aspect of the cutting method according to the present invention includes a first processing step for cutting a rough shape of the concave portion or the stepped portion, and a third processing step for cutting and removing a processing remaining portion of the first processing step. In the third machining step, the tool is moved backward with respect to the machining remainder of the first machining step after being cut mainly in the axial direction, and the tool is moved in the radial direction. The tool is moved by a predetermined amount, and this tool is again moved mainly in the axial direction to cut and then retreat, and the remaining machining portion is cut and removed. In the third machining step, the tool is mainly moved in the axial direction along the surface of the concave portion or the stepped portion with respect to the remaining machining portion of the first machining step, and is cut by performing an oblique thrust operation.

  According to the cutting method configured as described above, the first processing for forming the approximate shape of the concave portion or the stepped portion is performed using the tool, and the tool is applied to the remaining processing portion remaining in the first processing. Cutting is carried out mainly in the axial direction along the surface of the recess or step portion, and the tool is moved backward to move in a free direction to a predetermined amount in the radial direction along the extending direction of the recess or step portion. Then, at the moved position, the tool is again moved along the surface of the concave portion or the stepped portion to advance mainly in the axial direction and cut back, and this operation is repeated to form a wall portion along the concave portion or the stepped portion. . Thus, in the third machining step, the tool is cut along the surface of the concave portion or the stepped portion, that is, the wall is machined by an oblique thrust operation by moving the tool mainly in the axial direction. Thus, a large reaction force does not act on the workpiece, so that the vibration of the tool can be suppressed and the machining efficiency can be increased, and the machining accuracy can be increased. Moreover, control is easy and cutting can be performed easily.

  A third aspect of the cutting method according to the present invention includes a first processing step for cutting a rough shape of the concave portion or the step portion, and second and third processing for cutting and removing a processing remaining portion of the first processing step. A cutting method comprising a machining step, wherein the second machining step moves the tool in the axial direction with respect to the machining remainder of the first machining step, cuts the tool, and then retracts the tool to form a recess or step. The tool is moved by a predetermined amount in the radial direction along the extending direction of the tool, the tool is advanced again in the axial direction, cut and then retreated, and the remaining machining is removed by cutting. The tool is moved backward with respect to the remaining machining portion of the second machining step after cutting mainly in the axial direction, and this tool is moved by a predetermined amount in the radial direction along the extending direction of the recess or stepped portion. , This tool again proceeds mainly in the axial direction Is characterized by cutting and removing the machining remainder by repeating the operation for after recession was cut by.

  The cutting method of the present invention configured as described above performs a first cutting process for forming a rough shape of a concave portion or a stepped portion using a tool, and a remaining processing portion remaining in the first cutting process. Then, the tool is advanced in the axial direction for cutting, and the tool is moved backward to move in a free state in the radial direction along the extending direction of the recess or stepped portion. Then, the tool is advanced again in the axial direction at the moved position, cut and then retracted, and this operation is repeated to form a groove along the recess or step. After that, the tool is moved mainly along the surface of the recess or stepped portion along the surface of the recess or stepped portion with respect to the remaining machining portion of the second machining step, and then cut back to a free state, and the extension of the recess or stepped portion is made. It moves by a predetermined amount in the radial direction along the exit direction. Then, at the moved position, this tool is again moved along the surface of the recess or stepped portion mainly in the axial direction and then cut back, and this operation is repeated to form a wall portion along the recessed portion or stepped portion. To do. In this way, in the second machining step, the tool cuts the groove by moving in the axial direction, and in the third machining step, the tool cuts the wall by moving mainly in the axial direction. The reaction force does not act greatly, the vibration of the tool can be suppressed and the machining efficiency can be increased, and the machining accuracy can be increased. In the cutting method of the present invention, the absolute value of the reaction force acting on the tool (the combined value in the XYZ three-axis directions) is not reduced.

  As a preferable specific aspect of the cutting method according to the present invention, the second machining step is performed by moving the tool with a short axial stroke and performing shallow thrust cutting, and then moving the tool with a long axial stroke. It is characterized by deep and deep cutting. Multi-stage cutting may be performed by gradually increasing the axial stroke in a plurality of stages. If comprised in this way, even if a recessed part or a level | step difference part is deep, a recessed part and a groove part can be formed with a sufficient precision at a 2nd process process. Moreover, breakage can be prevented even if the diameter of the tool is small.

  Further, as another aspect of the cutting method according to the present invention, in the first aspect described above, after the second processing step, the tool is mainly used in the axial direction with respect to the remaining processing portion of the second processing step. After moving and cutting, the tool is moved backward, the tool is moved in the radial direction by a moving amount smaller than a predetermined amount of movement in the second machining step, and the tool is moved again mainly in the axial direction and then moved backward. And a fourth machining step of performing a remaining corner machining to finish a predetermined surface by cutting and removing the machining remaining portion by repeating the above operation. According to this configuration, the tool is moved by a movement amount smaller than a predetermined amount of movement of the tool used in the second machining process in the fourth machining process, and the machining remainder and the cusp part in the second machining process are allowed. The surface is cut and removed to a predetermined smooth surface. This fourth machining step is also an oblique butt machining mainly based on the butt movement according to the surface of the recess or stepped portion, and the tool used in the fourth machining step is less likely to generate vibration during cutting, Improvement of machining efficiency and machining accuracy are achieved.

  As still another aspect of the cutting method according to the present invention, in the second aspect or the third aspect described above, after the third processing step, a tool is applied to the remaining processing portion of the third processing step. Along the surface of the recess or step portion, the axial direction is mainly advanced to cut and then retreat, and this tool is moved in the radial direction along the extending direction of the recess or step portion. The tool is moved by a movement amount smaller than a predetermined amount, and the tool is moved along the surface of the recessed portion or the stepped portion again, the axial direction is mainly advanced to cut and then retreat, and the machining remaining portion is cut and removed. It is characterized by comprising a fourth processing step for performing the remaining corner processing to finish a predetermined surface. According to this configuration, the tool is moved by a movement amount smaller than a predetermined amount of movement of the tool used in the third machining process in the fourth machining process, and the remaining machining part and the cusp part in the third machining process are cut. The tool used in the 4th machining process is less likely to vibrate during cutting because it is an oblique thrust process that is finished with a predetermined surface and is mainly thrust along the surface of the recess or step. Improvement of machining efficiency and machining accuracy are achieved.

  According to the present invention, after forming the rough shape of the concave portion or the stepped portion, the remaining processing portion is cut and removed by the thrusting operation of moving and cutting the tool in the axial direction, and the tool is not moved in the lateral direction, or the tool is The remaining part of the work is cut and removed by the oblique thrusting operation that moves in the axial direction, and the tool moves less in the lateral direction, so that a large working reaction force does not act on the tool during cutting. Is prevented from vibrating. For this reason, machining accuracy can be improved, lateral movement (pick amount) of the tool can be increased, and machining efficiency can be increased. In addition, the cutting edge portion of the tool is prevented, and the durability of the tool can be improved.

  Hereinafter, a first embodiment of a cutting method according to the present invention will be described in detail with reference to the drawings. 1A and 1B show a metal material to be cut by the cutting method according to the present embodiment, wherein FIG. 1A is a perspective view in which a recessed groove portion is formed, FIG. 1B is a perspective view in which a step portion is formed, and FIG. (D) is a sectional view in the longitudinal direction, FIG. 2 is a plan view and a sectional view for explaining the cutting operation, FIG. 3 is a perspective view for explaining the cutting operation, and FIG. FIG. 5 is a perspective view and a cross-sectional view illustrating in detail the cutting operation of FIG. 3d, and FIG. 6 is another operation of the cutting operation of FIG. 3d. FIG. 7 is a flowchart for explaining the operation of the cutting method. In addition, this embodiment respond | corresponds to the 3rd aspect described in Claim 3 of the cutting method which concerns on this invention.

  First, a cutting method for forming a concave groove 2 as a concave portion in a metal material 1 such as a mold will be described with reference to FIG. In the metal material 1 shown in FIG. 1a, a groove 2 is formed using a tool such as a milling cutter or an end mill. The concave groove portion 2 is formed by inclined surfaces 2a and 2b whose wall surfaces on both sides are curved, and has a shape in which a small rounded portion 2c is formed at the tip of the lower end, and is dug in the Z-axis direction from the upper surface. It extends in the axial direction. Moreover, although mentioned later in detail, the level | step-difference part 3 is formed in 1 A of metal raw materials shown by FIG. 1b. The metal material 1B shown in FIGS. 1c and 1d is formed with a recess 4 whose both ends are closed. The cutting method of the present invention is a processing method for forming the concave groove portion 2, the stepped portion 3, and the concave portion 4 as described above, for example, in a metal block used in a mold or the like.

  When forming the concave groove portion 2 having the shape as shown in FIG. 1a, first, in the first machining step shown in step S1, as shown in FIGS. 2a, b and 3a, the first large diameter tool 10 is formed. Cutting is performed using. The tool 10 uses, for example, a ball end mill with a ball-shaped tip, but a flat end mill with a flat tip or a radius end mill with a chamfered corner may be used in accordance with the shape of the bottom surface of the groove. .

  In the first processing step S1 using the ball end mill 10, for example, while the ball end mill is rotated, the ball end mill 10 is moved to the axial direction (Z direction) and cut to a predetermined depth. It moves in the extending direction, that is, in the radial direction (X direction) at a predetermined cutting speed, and is cut into the approximate shape 20 of the groove portion 2. The concave groove portion 2 has a small radius of curvature of the rounded portion 2c at the bottom, and a concave groove portion having a desired shape cannot be obtained by cutting with the tool 10, and the remaining machining portion 21 of the first machining step is used as another tool, that is, Cutting is performed using the second and subsequent tools described in (1). In the first machining step S1, a cutting tool can be shortened because a large-diameter tool can be used. In the first machining step, the first ball end mill 10 may be cut while being advanced only in the axial direction, moved backward in the radial direction, and may be cut in the radial direction. It does not specify the direction.

  Next, the machining remaining portion 21 of the first machining process is cut and removed in the second machining process S3, but before that, the necessity of the second machining process is determined in step S2. Specifically, the wall due to the machining residue on both sides after the groove machining in the second machining step is performed so that the cutting on the side surface of the tool on the traveling direction side of the tool is not performed during the wall machining in the third machining step S5. If it is determined that both wall heights H0 are equal to or greater than the predetermined lateral running allowable height, the second processing step is performed. On the other hand, after it is determined that there is a wall due to the remaining machining on only one side after grooving in the second machining step, or even if walls are formed on both sides, at least the wall height on one side will run sideways. If it is determined that the value is less than the value, the second processing step is not performed. This determination will be described in detail with reference to FIGS.

  Further, in step S2, it may be determined whether the remaining machining portion 21 in the first machining step is within a range that can be sufficiently machined in the third machining step S5 without performing the second machining step S3. For example, when the radius of the rounded portion 2c at the lower end of the concave groove portion 2 is relatively large and the height of the processing remaining portion 21 is relatively small, the second processing step is omitted, and the third processing step is directly performed. Can be migrated. Thus, for example, if it can be determined that the second machining step is unnecessary at the design stage, the second machining step is passed, and a program is created so as to shift to the third machining step. Note that the necessity of the second processing step may be determined by visually judging the height of the processing remaining portion 21 and the like and determining whether or not to implement it.

  If there is a need for the second processing step, the second processing step S3 shown in step S3 is performed. In the second machining step, as shown in FIGS. 2c, d, and 3b, the small-diameter flat end mill 11 is rotated as the second tool while being advanced in the axial direction (Z direction), and the first machining is performed by the thrusting operation. The remaining machining portion 21 left in the process is cut. The hole 22a is cut by moving the flat end mill in the axial direction to a depth at which the tip of the flat end mill 11 contacts the curved inclined surfaces 2a and 2b on both sides or slightly above the depth. Then, the flat end mill 11 is moved backward to be separated from the metal material 1 to be free, and the flat end mill is moved in the radial direction (X direction) by a predetermined amount (pick amount D1) in the extending direction of the groove 2. . Thereafter, the flat end mill 11 is advanced again in the axial direction at the moving position, and the machining remaining portion 21 is cut by the pushing operation to form the hole 22b, and the backward movement is repeated to make the holes 22a, 22b. A groove portion 22 is formed along the extending direction (X direction) of the recessed groove portion 2.

  In this second processing step, as shown in FIG. 2c, both end portions in the longitudinal direction (X direction) of the groove portion 2 are open, and the first hole 22a is cut away from the end portion of the groove portion. Perform by processing. Next, the second hole 22b is cut adjacent to the first hole 22a (lower side in the drawing) on the end side of the groove. Then, the third hole 22c, the fourth hole 22d, etc. are cut adjacent to the opposite side of the first hole 22a (upper side in the figure), and the other end of the groove is cut. Thus, the groove part 22 along the groove part is formed in the center part of the groove part 2 from one side to the other side. The holes 22a, 22b,... May be cut from the open end, but if the end is cut, a large reaction force in the X direction is generated on the tool, causing the tool to vibrate. This is not preferable because the blade part is broken. Further, by opening the cutting portion with the second hole 22b, it is possible to prevent chipping and to prevent the cutting edge of the tool from being lost.

  In this way, in the second processing step, the groove portions 22a, 22b... Formed by moving the flat end mill 11 only in the axial direction (Z direction) are continuously formed in the X direction to form the groove portions 22 on both sides of the groove portions. Becomes the remaining processing portions 23 and 23 of the second processing step, and the lower portion of the groove portion becomes the remaining processing portion 24. Since the groove portion 22 is formed with a continuous hole portion, the bottom surface of the groove portion 22 is flat, a cylindrical surface is continuously formed on the side surface (wall surface), and an arc-shaped stepped cusp portion 25 is formed. The height h of the cusp portion differs depending on the diameter of the flat end mill 11 and the amount of movement in the radial direction (pick amount D1). When the tool diameter is large, the height of the cusp portion 25 decreases, and the holes 22a, 22b,. When the pitch (pick amount D1) is set large, the height of the cusp portion becomes large.

  In this way, in the second machining step, the flat end mill 11 is cut by a thrusting operation that moves forward in the axial direction (Z direction), so that the flat end mill 11 has a machining reaction in the radial direction (X direction, Y direction). Since the force is small, it can be moved by a large lateral movement amount (pick amount) D1, and the processing efficiency can be increased. Further, since the flat end mill 11 has a small processing reaction force in the radial direction, it is difficult for vibration to occur at the tip portion, and the processing accuracy of the groove portion 22 in which the hole portions 22a, 22b,.

  Further, in the second machining step, when the machining depth is not so large as shown in FIG. 2d, one cutting process is sufficient, but the machining distance is large, and the moving distance for moving the flat end mill 11 in the axial direction is sufficient. When is large, it is preferable to perform cutting several times by dividing the moving distance. That is, although not shown, the flat end mill is moved with a short axial stroke to perform shallow piercing to form a shallow groove in the X direction, and then moved with a long axial stroke to deep groove by deep piercing. Are formed in the X direction. If the desired depth is not reached even after dividing into two times, the axial stroke is further lengthened to perform multi-stage piercing. By performing multi-step piercing in this way, even when a tool such as an end mill cuts deeply with a small diameter, it can be prevented from being broken because it cuts stepwise.

  Thereafter, the remaining machining portions 23 and 24 of the second machining step S3 are cut and removed in the third machining step S5, but before that, the necessity of the third machining step is determined in step S4. Specifically, in step S4, when it is determined that the thickness of the remaining machining portion is equal to or greater than a predetermined tool allowable depth of cut so that a plurality of depths of cutting are not required at the time of ball end milling in the subsequent process, Step 3 is performed. Further, it is determined whether the remaining machining portions 23 and 24 in the second machining step are within a range that can be sufficiently machined in the fourth machining step S6 without performing the third machining step S5. For example, when the radius of the rounded portion 2c at the lower end of the recessed groove portion 2 is relatively large and the thickness of the processing remaining portion 24 is small, the third processing step S5 is omitted, and the fourth processing step S6 is directly performed. Can be migrated. Also in this case, for example, since the necessity of the third machining process can be determined at the design stage, a program can be created in advance. Moreover, you may judge the presence or absence of necessity visually.

  If there is a need for the third processing step, the third processing step shown in step S5 is performed. In the third machining step, as shown in FIGS. 2e, f, and 3c, for example, a flat end mill 11 is used as a third tool, and this flat end mill is moved forward in the axial direction (Z direction), The remaining machining portion 23 in the second machining step is cut. The operation of mainly moving in the axial direction is to move the flat end mill 11 in the axial direction (Z direction) and move it in the Y direction toward the center of the groove 2 with a movement amount smaller than the movement amount in the axial direction. It is an operation, and is actually moved along the inclined surfaces 2a and 2b and the curved surface. When the inclination angle of the inclined surface exceeds 45 degrees, the movement distance in the Y direction is smaller than the movement distance in the Z direction, and the tool can be moved mainly in the axial direction.

  That is, the wall surface 26 is formed to the lower end of the groove part 22 along the curved inclined surface 2a. As described above, the tool 11 is moved mainly in the axial direction, so that the tool is cut mainly in the pushing operation. Therefore, the machining reaction force in the radial direction is reduced, and the deflection amount of the tool 11 is reduced. For this reason, the vibration at the time of cutting of the flat end mill 11 is prevented, and the processing accuracy is improved. Further, the pick amount D2 to be moved in the X direction can be set large, and the processing efficiency can be increased. In addition, although the same flat end mill 11 as the 2nd tool was used as a 3rd tool, you may use other tools, such as a radius end mill.

  When one wall surface 26 is formed, the flat end mill 11 is moved backward, and the flat end mill is separated from the metal material 1 to be in a free state. Then, the flat end mill 11 is moved in the Y direction to perform the opposite wall processing. That is, the flat end mill 11 enters and moves along the opposite inclined surface 2 b to form the wall surface 27 up to the lower end of the groove 22. After the wall surfaces 26 and 27 are formed on the inclined surfaces 2a and 2b facing each other, the flat end mill 11 is moved along the X direction, and the flat end mill 11 enters and retreats at the moved position to sequentially form the wall surfaces 26 and 27. To do. Since the flat end mill 11 is mainly moved in the axial direction (Z direction), a large machining reaction force does not act at the time of cutting, and the flat end mill 11 can be moved by a large lateral movement amount (pick amount) D2 in the X direction. Can be increased.

  In the third machining step S5, the wall surface on both sides is cut with the groove portion 22 formed in the second machining step S3 as the center, but after the one side machining is performed along one inclined surface 2a, the other side It is preferable to process the other side along the inclined surface 2b. In this way, by alternately performing the cutting process by the flat end mill 11 as the third tool around the groove part 22, the cusp part 25 of the opposing machining remaining part 23 remaining in the second machining process is hardly affected. Cutting is possible. That is, since the opposite cusp part is cut about half in the third processing step on one side, the influence of the cusp part is reduced when the flat end mill 11 is advanced and moved to the center of the concave groove part. .

  In other words, as shown in FIG. 4a, when all of the one inclined surface 2a is cut and then the other inclined surface 2b is cut, the cusp portion 25 formed in the second machining step enters the protruding position. The tool 11 that has been touched and interferes. That is, as shown in FIG. 4c, even if the tool 11 enters the portion where the width of the groove portion 22 is large, it does not come into contact with the opposite wall surface. However, as shown in FIG. Contact and interfere with the opposite wall. When the tool 11 interferes with the wall surface in this manner, a machining reaction force in the radial direction acts on the tool and vibrates to reduce the machining accuracy, and there is a possibility that the blade portion may be broken, as shown in FIG. By alternately cutting so as to cut the other inclined surface 2b after cutting one inclined surface 2a, the interference between the tool 11 and the cusp portion 25 can be reduced or prevented, and the accuracy of the third machining step can be prevented. Is improved, and the finished state of the recessed groove portion 2 can be improved.

  After the third processing step described above, a fourth processing step, which is a remaining corner processing, is performed to finish a predetermined surface. In the fourth machining step S6, as shown in FIGS. 3d and 5, the ball end mill 12 is used as the fourth tool, and the ball end mill 12 is rotated along the inclined surfaces 2a and 2b and the curved surface of the concave groove portion 2. The remaining machining portion 24 in the third machining step and the cusp portions of the wall surfaces 26 and 27 are cut. Since the ball end mill 12 performs cutting by moving mainly in the axial direction, cutting can be performed with a cutting edge portion having a low peripheral speed at the tip of the tool, and a machining reaction force component in the thrust direction can be increased. Further, even when the tool length is long, it is possible to perform processing while suppressing the amount of bending of the tool. As a result, the vibration of the ball end mill 12 is prevented and the processing accuracy is improved. In addition, the tool life can be extended. Note that the fourth processing step S6 is not necessarily required when the surface of the groove portion 2 is finished sufficiently smoothly in the third processing step S5.

  The ball end mill 12 is moved along the inclined surface 2a on one side and cut, and then the ball end mill is moved back. The ball end mill 12 is moved along the inclined surface 2b on the opposite side and cut, and then the ball end mill is moved back. The tool is moved away from the metal material 1 to be in a free state, and the tool is moved in the radial direction by a moving amount (pick amount D3) along the extending direction (X direction) of the groove 2. The pick amount D3 may be set to the same amount as the amount of movement of the second tool 11 or the amount of movement of the third tool 11, but is preferably smaller than these amounts of movement. The cutting cusp height of the groove portion 2 can be reduced, and the finished surface state can be made smooth.

  In the fourth processing step S6, after cutting along the inclined surface 2a, the opposing inclined surfaces 2b are alternately cut. Then, as shown in FIGS. 5b to 5d, in order to improve chip discharge by cutting, the amount of movement to be advanced in the axial direction (Z direction) is divided into a plurality of times. That is, as shown in FIGS. 5a and 5b, the ball end mill 12 is first advanced along the arrows 28 and 29 at a high position of the inclined surfaces 2a and 2b to perform cutting, and then the inclined surface 2a as shown in FIG. 5c. 2b, the ball end mill 12 is advanced along the arrows 30 and 31 to perform cutting. Finally, as shown in FIG. 5d, the ball end mill 12 is moved to the positions of the arrows 32 and 32 at the lower positions of the inclined surfaces 2a and 2b. The cutting is performed in three stages by proceeding along 33. In general, tip piercing by a ball end mill has poor chip evacuation and cannot be cut efficiently, but cutting can be performed in stages in the Z direction to increase cutting efficiency.

  Also in the above-described fourth machining step S6, the movement of the ball end mill 12 is mainly in the axial direction, and the ball end mill is moved forward in the axial direction (Z direction) and moved in the central direction (Y direction) of the recessed groove portion 2. I am letting. Since the ball end mill 12 is not moved in the lateral direction (X direction) in this way, a large machining reaction force does not act in the radial direction of the ball end mill, and vibration of the ball end mill can be prevented to improve machining accuracy. Further, since the vibration of the ball end mill 12 is prevented, chipping of the ball end mill is prevented and durability can be improved.

  Further, in the fourth machining step, when the machining remaining portion 24 of the third machining step is removed by cutting, the machining may be performed as shown in FIG. In FIGS. 6a and 6b, the ball end mill 12 is gradually advanced along one inclined surface 2a, and cutting is performed by making it advance like 12a, 12b, and 12c. Next, the ball end mill 12 is gradually advanced along the inclined surface 2b on the other side, and the remaining machining remaining portions are advanced like 12d, 12e, and 12f to be cut. In this way, the ball end mill 12 is moved in the Z direction and moved in the Y direction to cut the remaining machining portion 24, and then the cutting is performed in the X direction successively to cut and remove all the remaining machining portion 24 in a smooth state. Thus, the groove portion 2 can be completed.

  In the fourth processing step, cutting can be performed as shown in FIG. In FIG. 6c, the ball end mill 12 cuts on the left inclined surface 2a side like 12g, and then cuts on the right inclined surface 2b side like 12h. Next, the cutting is performed by proceeding as 12i on the left side, and the cutting is performed by proceeding as 12j on the right side. Similarly, cutting is performed as 12k, 12l, 12m, and 12n alternately. Thereby, the processing reaction force component in the thrust direction can be further increased. Then, as described above, the end mill 12 is moved in the X direction to remove all the remaining machining portion 24 of the groove 2 to make a smooth surface.

  Next, another embodiment showing the first aspect of the present invention will be described. The cutting method of this embodiment performs an operation on the N side in the determination of the necessity of the third processing in step S4 in the flowchart of FIG. That is, this embodiment is characterized in that it is the first aspect of the present invention without the third processing step as compared to the first embodiment described above. Other substantially equivalent configurations are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this embodiment, the first machining step S1 cuts the rough shape of the concave portion and the stepped portion, the second machining step S2 performs the groove processing close to the bottom surface of the concave groove portion 2, and the second processing step. Since the remaining machining is within the allowable range, the third machining process is omitted and the machining is performed so as to proceed to the fourth machining process S6. That is, after the first machining step S1 and the second machining step S2, the height and width of the machining remaining portion are within the allowable range, so that the machining step for performing the third wall machining in step S4 is omitted. In the machining step S6, the remaining corners such as the cusp portion that is the remaining machining portion are removed.

  In this embodiment, after performing the first machining step using the first tool 10, the second machining step S <b> 2 for cutting the machining remaining portion 21 of the first machining using the second tool 11 is performed. Then, the fourth machining step S6 is performed. In the second machining step, the second tool 11 is advanced in the axial direction (Z direction) in the same manner as in the above embodiment, so that the second tool 11 is cut. No machining reaction force in the radial direction (X direction, Y direction) acts on. For this reason, it is possible to increase the picking amount D1 for moving the second tool 11 in the radial direction, that is, in the lateral direction by moving the second tool 11 in the axial direction and then retracting it, thereby increasing machining efficiency. In addition, since the second tool 11 hardly generates vibration, the processing accuracy can be improved.

  Further, in the fourth machining step S6, the fourth tool 12 enters and moves in the axial direction (Z direction) as a main direction, that is, is cut by oblique thrusting with a small horizontal movement distance with respect to the vertical direction. A large machining reaction force does not act on the fourth tool. For this reason, it is possible to increase the picking efficiency D3 by moving the fourth tool in the radial direction (X direction), that is, in the lateral direction after cutting with the fourth tool 12, and thereby increasing the machining efficiency. it can. Further, since the machining reaction force is small, the vibration of the tool 12 is prevented during cutting, and the machining accuracy can be increased. In this embodiment, since the concave portion or the stepped portion can be formed by removing the third processing step depending on the shape of the concave portion or the stepped portion, the processing time can be significantly reduced as compared with the first embodiment. it can.

  Still another embodiment showing the second aspect of the present invention will be described. The cutting method according to this embodiment performs an operation on the N side in the determination of the necessity of the second machining in step S2 in the flowchart of FIG. That is, this embodiment is characterized in that it is the second aspect of the present invention without the second processing step as compared to the first embodiment described above. Other substantially equivalent configurations are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this embodiment, the concave portion and the stepped portion are cut in the first processing step S1, and the remaining processing portion in the first processing step is within an allowable range. Therefore, the second processing step S3 is performed. Processing that is omitted and proceeds to the third processing step S5 is performed. That is, after the first machining step S1, the height, width, and the like of the machining remaining portion 21 are within an allowable range, so that there is no need for the machining step S3 in which the second groove machining is performed in step S2. In step S4, there is a need for the third machining step S5, and wall processing of the side surface of the groove 2 is performed in the third machining step S5. Thereafter, in the fourth machining step S6, the remaining corners such as the cusp portions that are the remaining machining portions are removed.

  In this embodiment, after performing the first machining process using the first tool 10, the third machining process S <b> 4 for cutting the machining remaining portion 21 of the first machining using the third tool 11 is performed. Then, the fourth machining step S6 is performed. In the third machining step, the third tool 11 is moved in the axial direction (Z direction) as in the previous embodiment, that is, in the horizontal direction with respect to the vertical direction. Therefore, a large machining reaction force does not act on the third tool 11. For this reason, the cutting amount can be increased after cutting with the third tool, and the pick amount D2 for moving the third tool in the radial direction, that is, in the lateral direction (X direction) can be increased. . Further, since the machining reaction force applied to the third tool 11 is small, the vibration of the tool is prevented during cutting, and the machining accuracy can be increased.

  Further, in the fourth machining step S6, the fourth tool 12 enters and moves in the axial direction (Z direction) as a main direction, that is, is cut by oblique thrusting with a small horizontal movement distance with respect to the vertical direction. A large machining reaction force does not act on the fourth tool. For this reason, it is possible to increase the picking efficiency D3 by moving the fourth tool in the radial direction (X direction), that is, in the lateral direction after cutting with the fourth tool 12, and thereby increasing the machining efficiency. it can. Further, since the machining reaction force is small, the vibration of the tool 12 is prevented during cutting, and the machining accuracy can be increased. In this embodiment, since the concave portion or the stepped portion can be formed by removing the second processing step depending on the shape of the concave portion or the stepped portion, the processing time can be greatly shortened as compared with the first embodiment. it can.

  Next, a case where the step 3 shown in FIG. 1b is cut by the cutting method of the present invention will be described with reference to FIG. 1b and FIG. The step portion 3 formed on the metal material 1A includes an upper surface 3a, a step surface 3b, and an inclined surface 3c connecting the upper surface 3a and the step surface 3b, and a corner portion between the inclined surface 3c and the step surface 3b. In addition, a small rounded portion 3d is formed. When forming the stepped portion, as shown in FIG. 8a, the arc portion 35 is cut along the X direction as a rough shape of the stepped portion in the metal block in the first processing step. An arc portion 35 having a large curvature radius is formed along the X direction using a first tool having a large radius (not shown). In the first machining step, since a tool having a large diameter can be used, movement in the X direction can be performed quickly, the machining efficiency can be increased, and cutting can be performed in a short time.

  After the first machining step, as shown in FIG. 8b, a second machining step is performed in which the groove portion 36 is cut along the X direction using the flat end mill 11 as the second tool. The flat end mill 11 is rotated to advance in the axial direction (Z direction), cut, retreat, move away from the metal material 1A, and then move in the X direction with the pick amount D1 to repeat the holes 36a, 36b. ... are continuously formed to form the groove 36. In this embodiment, since the radius of the circular arc portion 35 is large and the height H1 of the remaining machining portion is large even if the groove portion 36 is formed, the groove portion 36 is advanced to a distance that does not reach the bottom surface 3b in order to form another groove portion. ing.

  That is, as shown in FIG. 8 c, after the groove portion 36 is formed by the flat end mill 11, the groove portion 37 is formed in parallel with the groove portion 36. This groove portion 37 is also formed by repeating the cutting operation of moving the flat end mill 11 in the axial direction to the stepped surface 3b, cutting it slightly deeper than the groove portion 36, then retracting it and moving it in the X direction. In this second machining step, the grooves 36 and 37 are cut in parallel, but also in this second machining step, the tool 11 such as a flat end mill advances along the axial direction for cutting. The machining reaction force in the radial direction does not act on the tool 11, and the pick amount D1 to be moved in the X direction can be set large, so that the machining efficiency can be increased. Moreover, since the machining reaction force in the radial direction does not act on the tool 11, the vibration of the tool is prevented, and the machining accuracy can be increased.

  Thus, after performing the 2nd processing process in two steps, as shown in Drawing 8d, it shifts to the 3rd processing process. In the third processing step, the flat end mill 11 is mainly moved in the axial direction (Z direction) to cut the second processing remaining portion. That is, the flat end mill 11 used in the second machining is used as it is as the third tool, and is moved along the inclined surface 3c and is moved horizontally along the step surface 3b to perform wall machining and bottom machining. Do. Since the movement along the inclined surface 3c is mainly movement in the axial direction, a large machining reaction force does not act on the tool 11, and even the movement along the stepped surface 3b is large because the thickness of the remaining machining portion is small. The machining reaction force does not act, and the machining can be carried out by moving in the X direction with a large pick amount D2, thereby improving the machining efficiency. The movement mainly in the axial direction means an oblique thrusting process in which the movement is large in the Z direction and small in the Y direction. Further, during cutting, the tool 11 is unlikely to vibrate, and the processing accuracy is improved.

  After the third processing step, a fourth processing step is performed as shown in FIG. 8e, and the remaining processing portion of the third processing step is cut off. The ball end mill 12 is used as the fourth tool, and the cusp portion or the like that is the remaining processing portion of the third processing step is cut. The ball end mill 12 is moved along the inclined surface 3c mainly in the axial direction to cut and remove the cusp portion to finish the wall surface smoothly. Since the stepped surface 3b is flattened by the flat end mill 11 in the previous step, the processing by the ball end mill is not particularly required. Also in this wall machining, since the tool 12 is mainly advanced in the axial direction, a large machining reaction force does not act on the tool, the pick amount D3 to be moved in the X direction can be set large, and the machining efficiency can be increased. Further, the tool 12 is less likely to vibrate and the machining accuracy is improved.

  In this embodiment, as shown in FIGS. 8B and 8C, the second machining process is performed in two stages to form the groove 36 and the groove 37. However, the arc formed in the first machining process is shown. When the radius of curvature is small, such as the arc portion 35A shown in FIG. 8f, and the height H2 of the remaining machining portion 36A of the groove portion 36A cut and formed by the flat end mill 11 in the second machining step is within the allowable range H. Can finish the second processing step with only one groove formation. That is, since the height H2 is small, the second machining process can be completed in one stage when it is in a range that can be sufficiently cut by the next third machining process.

  Furthermore, the case where the cutting process of the closed recessed part 4 shown in FIG. 1c is performed with the cutting method of the present invention will be described with reference to FIG. When the concave portion 4 is formed in the metal material 1B, the second processing step is performed after the rough shape 41 of the concave portion is cut along the X direction in the first processing step shown in FIGS. 9a, 9b, and 9c. In the second machining step, a second tool such as a flat end mill is used, and cutting is performed by advancing the tool in the axial direction (Z direction) as in the above embodiment. In this case, the first hole 42a is cut by thrusting while being separated from the end of the recess 4. Next, the second hole 42b is cut on the end side of the recess adjacent to the first hole (left side in the figure). Then, the third hole 42c, the fourth hole 42d, etc. are cut adjacent to the opposite side of the first hole (right side in the figure), and the other end of the recess 4 is cut.

  In this way, a groove portion 42 is formed from one side to the other side in which a hole formed along the recess is continuous at the center of the recess 4. Thus, since the groove part 42 is formed by connecting the hole parts, the cusp part 43 where the adjacent arcs are joined is formed on the side surface of the groove part, and the cusp part increases as the pitch (pick amount) of the continuous hole parts increases. Height increases. When the groove is formed deeper in the second processing step, a groove 44 is further formed below the groove 42 as shown in FIG. 9d. The groove portion 44 is also cut to the bottom surface 45 of the groove portion 4 or near the bottom surface by advancing the tool in the axial direction, and the remaining machining portion in the first machining step is removed. When the radius of curvature of the bottom of the groove 4 is small, it is preferable to use a tool having a small diameter for forming the lower groove 44. Since the cutting of the grooves 42 and 44 in the second machining step is also performed by advancing the tool in the axial direction, the machining reaction force in the radial direction does not act on the tool, and a large amount of pick can be taken to move in the X direction. Therefore, the processing efficiency can be increased. In addition, since the tool is unlikely to vibrate, it is possible to prevent the cutting edge of the tool from being lost and improve the processing accuracy.

  Thereafter, as in the above-described embodiment, the necessity of the third machining step S5 is determined in step S4, and if necessary, the third machining step is performed. In the third machining step S5, a wall portion on the side surface of the groove formed by grooving in the second machining step S3 using a third tool such as a flat end mill or a ball end mill, as in the above embodiment. Processing is performed. That is, as shown in FIG. 9e, the removal of the machining remaining portion and the cusp portion 43 formed on the wall surface of the groove portion 42 is performed mainly in the axial direction of the tool, and the cutting portion 46a is formed with the third tool. Then, the tool is retracted, and the tool is mainly advanced in the Z direction along the wall surface at the position where the tool is moved in the X direction to form the cutting portion 46b. Next, the cutting portions 46c, 46d,... Are formed in the same manner, and this operation is repeated to cut and remove the remaining processing. Also in this example, it is preferable that the cutting parts of the third processing are alternately cut and removed along the X direction.

  Further, although not shown after the third machining step S5, the remaining corner portion is cut and removed in the fourth machining step S5 as necessary, as in the above embodiment. In this fourth machining step, a tool such as a ball end mill is used to remove the cusp portion or the like that is the third machining remaining portion to make it smooth and complete the shape of the recess 4. In the second processing step shown in FIG. 9a, the first hole 47a is formed on the right side of the first hole 42a in FIG. 9a as shown in FIG. 9f, and then the second hole 47b and the third hole 47c are formed on the left side. , The order may be changed so that the third hole 47d and subsequent holes are formed on the right side.

  Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention described in the claims. Design changes can be made. For example, although the example in which the recessed part, the recessed groove part, the step part, and the like are formed by an inclined surface is shown, a shape in which the recessed part or the like is formed by a vertical surface may be used. Moreover, the tool used at each process can use appropriate tools, such as a milling machine and various end mills.

  As an application example of the present invention, for example, a block-shaped metal lump other than the mold can be cut using this cutting method. In addition, the object to be cut is not limited to metal, and can be applied to cutting use of any material.

The metal raw material used by one Embodiment of the cutting method which concerns on this invention is shown, (a) is a perspective view of the state which formed the ditch | groove part, (b) is a perspective view of the state which formed the level | step difference part, (c) Is a perspective view of a state in which a recess is formed, (d) is a cross-sectional view along the longitudinal direction of (c). Operation | movement description of the cutting method of the ditch | groove part shown to Fig.1 (a) is shown, (a), (b) is the top view and sectional drawing which show a 1st process process, (c), (d) is 2nd. The top view and sectional drawing which show these processing processes, (e), (f) is the top view and sectional drawing which show a 3rd processing process. The operation | movement description of the cutting method which concerns on this invention is shown, (a) is a perspective view which shows a 1st process process, (b) is a perspective view which shows a 2nd process process, (c) is a 3rd process process. FIG. 8D is a perspective view showing a fourth processing step. 3 (c) shows in detail the operation of the third machining step, (a) and (b) are plan views showing the cutting sequence, and (c) and (d) are AA lines in (a). Sectional drawing and BB sectional drawing. The operation | movement description of the 4th manufacturing process of FIG.3 (d) is shown in detail, (a) is a perspective view, (b)-(d) is sectional drawing which shows a cutting step. Sectional drawing which shows the other example of operation | movement description of the 4th manufacturing process of FIG.3 (d) in detail. The flowchart which shows operation | movement description of the cutting method which concerns on this invention. The perspective view explaining operation | movement which cuts the level | step-difference part shown to FIG. 1b. The operation | movement description which cuts the recessed part shown to FIG. 1c is shown, (a) is a top view which shows a 2nd manufacturing process, (b) is the CC sectional view taken on the line, (c) is DD sectional view. (D) is principal part sectional drawing of other operation | movement description, (e) is a top view which shows a 3rd process process, (f) is a top view which shows the other operation | movement description of a 2nd process process. The conventional cutting method is shown, (a) is a cross-sectional view of the pre-processing of the recess, (b) is a cross-sectional view of the post-processing, (c) is a cross-sectional view of the pre-processing of the step portion, (d) is the post-processing Sectional drawing.

Explanation of symbols

  1: metal material, 2: concave groove (recess), 2a, 2b: inclined curved surface, 2c: rounded portion, 3: stepped portion, 3a: upper surface, 3b: stepped surface, 3c: inclined surface, 3d: rounded portion, 4 : Concave part, 10: Ball end mill (first tool), 11: Flat end mill (second and third tools), 12: Ball end mill (fourth tool), 20, 41: Outline of first processing step Shape, 21, 23, 24: processing remainder, 22, 36, 36A, 37, 42: groove, 22a, 22b ..., 42a, 42b ...: hole, 25: cusp part (processing rest), 35, 35A: arc Part (schematic shape of the first machining process), S1: first machining process, S3: second machining process, S5: third machining process, S6: fourth machining process, D1: second tool Movement amount (pick amount), D2: third tool movement amount (pick amount), D3: The amount of movement of the 4 of the tool (the amount of pick)

Claims (6)

A cutting method comprising: a first processing step of cutting a rough shape of a recess or a step portion; and a second processing step of cutting and removing a processing remaining portion of the first processing step,
In the second machining step, the tool is advanced in the axial direction with respect to the machining remainder of the first machining step, cut and then retracted, the tool is moved by a predetermined amount in the radial direction, and the tool is re-axially moved. A cutting method characterized by cutting and removing the remaining machining portion by repeatedly moving in a direction and cutting and then moving backward. A cutting method comprising: a first processing step of cutting a rough shape of a recess or a step portion; and a third processing step of cutting and removing a processing remaining portion of the first processing step,
In the third machining step, the tool is moved backward with respect to the remaining machining portion of the first machining step after being cut mainly in the axial direction, and the tool is moved by a predetermined amount in the radial direction. The cutting process is characterized in that the remaining part of the process is cut and removed by repeating the operation of retreating after cutting with the axial direction mainly advanced again. A cutting method comprising: a first processing step of cutting a rough shape of a recess or a step portion; and a second and third processing step of cutting and removing a processing remaining portion of the first processing step,
In the second machining step, the tool is moved in the axial direction with respect to the machining remaining portion of the first machining step, cut and then retracted, and the tool is moved in the radial direction along the extending direction of the recessed portion or the stepped portion. Move by a predetermined amount, and repeat the operation of moving the tool in the axial direction again and cutting it back and then removing the remaining machining by cutting,
In the third machining step, the tool is moved backward with respect to the remaining machining portion of the second machining step after being cut mainly in the axial direction, and the tool is moved along the extending direction of the recessed portion or the stepped portion. A cutting method characterized by moving the tool by a predetermined amount in the radial direction and cutting and removing the remaining machining portion by repeatedly moving the tool again in the axial direction and then cutting back.   2. The second machining step according to claim 1, wherein after the tool is moved with a short axial stroke to perform shallow piercing, the tool is moved with a long axial stroke to perform deep piercing. 3. The cutting method according to 3.   After the second machining step, the tool is moved backward in the axial direction with respect to the machining remaining portion of the second machining step and then moved backward, and the tool is moved in the radial direction in the second machining step. The tool is moved by a movement amount smaller than a predetermined amount, the operation of the tool is again advanced mainly in the axial direction, and then the operation of retreating is repeated to cut and remove the remaining machining portion, and the remaining corner machining is performed to finish the predetermined surface. The cutting method according to claim 1, further comprising a fourth machining step.   After the third machining step, the tool is moved in the axial direction with respect to the remaining machining portion of the third machining step and then moved backward, and the tool is moved in the radial direction in the third machining step. The tool is moved by a movement amount smaller than a predetermined amount, the operation of the tool is again advanced mainly in the axial direction, and then the operation of retreating is repeated to cut and remove the remaining machining portion, and the remaining corner machining is performed to finish the predetermined surface. The cutting method according to claim 2, further comprising a fourth machining step.

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