JP2009220218A - Method of cutting pocket by end mill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of cutting a pocket by an end mill, improving a machining efficiency by cutting at a large feed rate without lowering a machining accuracy by changing a cutting method using an existing end mill. <P>SOLUTION: In this method, the end mill T so disposed as to be orthogonal to a bottom surface is used for the finish tolerance of the pocket comprising a bottom surface finish tolerance Rt along the bottom surface, a wall surface finish tolerance Rk along a wall surface, and a corner tolerance Cn in the position where the bottom surface finish tolerance Rt and the wall surface finishing tolerance Rk overlap with each other. Only one of the bottom surface finish tolerance Rt from which the corner tolerance Cn is excluded, or the wall surface finish tolerance Rk from which the corner tolerance Cn is excluded is at first cut in a first cutting step. The remaining tolerance including the corner tolerance is cut, and the bottom surface finish tolerance from which the corner tolerance is excluded and the wall surface finish tolerance from which the corner tolerance is excluded are cut separately in a second cutting step. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pocket-shaped cutting method using an end mill used in molding of a mold or the like.

Conventionally, when machining a pocket shape in a mold (work), a blade extending from the tip center Tc of the substantially cylindrical tool to the tip outer periphery and further from the tip outer periphery to the tool side rear end side is provided. The obtained end mill T (see FIGS. 3A and 3B) is used for processing.
Here, the conventional finish cutting in the pocket shape of the cylindrical space will be described with reference to FIG. First, the bottom surface finishing allowance Rt is left on the bottom surface of the pocket Po, and the wall surface finishing allowance Rk is left on the wall surface of the pocket Po. These are cut with an end mill T to obtain a finished shape. FIG. 6B shows a plan view of the pocket Po as viewed from the opening side, and FIG. 6A shows a CC cross-sectional view in FIG. 6B. The shape of the pocket Po is not limited to a cylindrical shape.
As shown in FIG. 6A, in the conventional cutting method, first, the end mill T [1] is moved along the inner wall of the pocket at the position where the end mill T is inserted a predetermined distance L [1] from the pocket entrance. It is moved in the direction orthogonal to TZ, and the wall surface finishing allowance Rk [1] (see FIG. 6C) is cut on the tool side surface of the end mill T. Here, if the distance L [1] is too long, the amount of cutting by the tool side surface of the end mill T increases, cutting resistance increases, tool vibration may occur, and processing accuracy may decrease, so an appropriate distance ( Wall finish depth) is set.
Subsequently, the end mill T is further inserted by a predetermined distance L [2], the end mill T [2] is moved along the inner wall of the pocket in a direction perpendicular to the tool rotation axis TZ, and the wall surface is finished on the tool side surface of the end mill T. The machining allowance Rk [2] (see FIG. 6C) is cut. This operation is repeated, and at the position of the end mill T [3] where the end of the end mill T reaches the bottom surface finishing allowance Rt, the wall surface finishing allowance Rk [3] and the bottom surface finishing allowance Rt [3] are cut. .
Here, at the position of the end mill T [3], the wall surface finishing allowance Rk [3] and the bottom surface finishing allowance Rt [ 3] at the same time, cutting resistance increases, tool vibration occurs, and machining accuracy may be reduced. Therefore, in order to prevent the occurrence of this tool vibration, conventionally, the feed rate of the end mill T is reduced in the cutting of the corner removal allowance Cn.
However, since the feed rate of the entire cutting process is reduced by the feed rate of the corner removal allowance Cn, the machining time is lengthened and the machining efficiency is lowered.
Therefore, in the prior art described in Patent Document 1, by improving the shape of the end mill, it is possible to feed the end mill at a higher speed than in the past even when cutting at the corner removal allowance Cn, thereby improving machining efficiency. A radius end mill that can be made is proposed.
JP 2007-030074 A

In the prior art described in Patent Document 1, since the shape of the end mill, which is a cutting tool, is changed, the end mill of an existing machine tool must be replaced. A machining program corresponding to the replaced end mill is also required. Therefore, it takes a lot of time and money to create a machining program corresponding to the improved end mill and to arrange and replace the improved end mill.
The present invention was devised in view of such points, and by using an existing end mill and changing the cutting method, the cutting is performed at a higher feed rate without lowering the processing accuracy. It is an object of the present invention to provide a pocket cutting method using an end mill that can further improve efficiency.

As means for solving the above-mentioned problems, the first invention of the present invention is a pocket cutting method using an end mill as described in claim 1.
The pocket cutting method using an end mill according to claim 1 is provided with a blade that extends from the center of the tip of the substantially cylindrical tool to the outer periphery of the tip, and further extends from the outer periphery of the tip toward the rear end of the tool side surface. This is a pocket cutting method using an end mill that uses an end mill that rotates about an axis to finish-cut a pocket having a finishing allowance remaining on each of a bottom surface and a wall surface.
The pocket finishing allowance includes a bottom finishing allowance along the bottom surface, a wall finishing allowance along the wall surface, and a corner allowance where the bottom finishing allowance and the wall finishing allowance overlap. The pocket and the end mill are arranged so that the tool rotation axis is orthogonal to the bottom surface of the pocket, and the corner cutting allowance is removed in the first cutting step using the end mill. Only one of the bottom surface finishing allowance or the wall surface finishing allowance excluding the corner finishing allowance is cut first.
Then, in the second cutting process following the first cutting process, the remaining machining allowance including the corner machining allowance is cut, and the bottom surface finishing allowance excluding the corner machining allowance and the corner removing It is a pocket cutting method by an end mill, in which the wall surface finishing allowance excluding the allowance is cut separately without simultaneously cutting.

A second invention of the present invention is a pocket cutting method using an end mill as described in claim 2.
The pocket cutting method by the end mill according to claim 2 is the pocket cutting method by the end mill according to claim 1.
In the first cutting step, the tip of the end mill is disposed near the center of the bottom surface of the pocket, and the end mill is relatively positioned in the axial direction of the tool rotation axis with respect to the bottom surface of the pocket. Cut and cut using a bottom blade provided on the surface of the tip of the end mill, and then, from the cut position, the end mill is perpendicular to the tool rotation axis with respect to the pocket. The bottom surface finishing allowance excluding the corner finishing allowance for the bottom finish depth is provided on the tool side surface of the end mill without moving the wall finish finishing allowance relative to the direction. The bottom surface flat part cutting which cuts using a side blade is performed, and the bottom surface finishing allowance excluding the corner cutting allowance for the cutting and the bottom flat part cutting. Repeat until no, cutting only the bottom surface finishing allowance except for the corner allowance earlier than the wall finishing allowance.
In the second cutting step, the end mill and the pocket are arranged so that a tip of the end mill is inserted from the inlet portion of the pocket by a wall finishing depth, and the end mill is inserted into the tool with respect to the pocket. A wall surface that is moved in a direction perpendicular to the rotation axis and along the inner wall of the pocket to cut a wall surface finishing allowance for the wall surface finishing depth in the pocket using the side blade of the end mill. Contour cutting is performed, and after the wall surface contour cutting, the end of the end mill is further inserted by the wall surface finishing depth, and the wall surface contour cutting is performed to newly cut the wall finishing allowance for the wall surface finishing depth. The operation is sequentially repeated until the bottom of the pocket is reached, and the wall finishing allowance including the corner allowance is cut. It is a pocket cutting method by the mill.

The third invention of the present invention is a pocket cutting method by an end mill as described in claim 3.
The pocket cutting method by the end mill according to claim 3 is the pocket cutting method by the end mill according to claim 1.
In the first cutting step, the end mill and the pocket are arranged so that a tip of the end mill is inserted by a wall finishing depth from an entrance portion of the pocket, and the end mill is placed on the tool rotation axis with respect to the pocket. The wall surface excluding the corner machining allowance corresponding to the wall surface finishing depth in the pocket without cutting the bottom machining allowance by moving in a direction orthogonal to the inner wall of the pocket Wall finishing contour cutting is performed by using a side blade provided on the side surface of the tool of the end mill. After the wall contour cutting, the end of the end mill is further inserted by the wall finishing depth. The wall surface finishing allowance is newly cut by performing the contour cutting of the wall surface and excluding the corner allowance for the wall finishing depth. Work, and sequentially repeated until it reaches the bottom of the pocket, cutting only the wall finishing allowance except for the corner allowance earlier than the bottom surface finishing allowance.
In the second cutting step, the tip of the end mill is disposed near the center of the bottom surface of the pocket, and the end mill is relatively positioned in the axial direction of the tool rotation axis with respect to the bottom surface of the pocket. Cut by cutting and cutting using a bottom blade provided on the surface of the tip of the end mill, and then, from the cut position, the end mill is used as the tool rotation axis with respect to the pocket. Relatively moving in the orthogonal direction, the bottom surface finishing allowance including the corner removing allowance for the bottom finish depth is cut using the side blade of the end mill, and the bottom flat portion cutting is performed. Repeat the cutting and bottom surface flat part cutting until the bottom finishing allowance including the corner allowance is eliminated, including the corner allowance. Cutting the bottom surface finishing allowance, a pocket cutting method by the end mill.

A fourth invention of the present invention is a pocket cutting method by an end mill as described in claim 4.
The pocket cutting method by the end mill according to claim 4 is the pocket cutting method by the end mill according to any one of claims 1 to 3, wherein a shape of a boundary portion between the wall surface and the bottom surface of the pocket is the wall surface and the wall surface. A pocket cutting method using an end mill, which has an arc shape that smoothly connects the bottom surface, and a curved portion having a curvature corresponding to the arc shape is cut using a radius end mill provided on a blade near the outer periphery of the tip portion. is there.

In the pocket cutting method using the end mill according to claim 1, the pocket finishing allowance includes a bottom finishing allowance along the bottom surface, a wall finishing allowance along the wall surface, a bottom finishing allowance, and a wall finishing allowance. It is divided into the corner removal allowance of the position where overlaps.
Then, by not cutting both the bottom surface finishing allowance excluding the corner allowance and the wall surface finishing allowance excluding the corner allowance, an increase in cutting resistance is avoided.
Thereby, it is possible to cut at a larger feed speed without lowering the processing accuracy. Therefore, it is possible to increase the feed rate of the entire cutting process, and it is possible to further improve the processing efficiency using the existing end mill.

In the pocket cutting method using the end mill according to claim 2, only the bottom surface finishing allowance excluding the corner allowance is cut in the first cutting step. In the subsequent second cutting step, the wall surface finishing allowance is cut including the corner removing allowance.
By cutting in the above order, the cutting resistance increases without cutting both the bottom finishing allowance excluding the corner allowance and the wall finishing allowance excluding the corner allowance at the same time. Avoid that.
Thereby, it becomes possible to cut at a larger feed speed without lowering the machining accuracy using an existing end mill, and the machining efficiency can be further improved.

In the pocket cutting method by the end mill according to claim 3, only the wall surface finishing allowance excluding the corner removing allowance is cut in the first cutting step. In the subsequent second cutting step, the bottom finishing allowance including the corner removing allowance is cut.
By cutting in the above order, the cutting resistance increases without cutting both the bottom finishing allowance excluding the corner allowance and the wall finishing allowance excluding the corner allowance at the same time. Avoid that.
Thereby, it becomes possible to cut at a larger feed speed without lowering the machining accuracy using an existing end mill, and the machining efficiency can be further improved.

  According to the pocket cutting method using the end mill according to claim 4, the arc shape of the boundary portion between the bottom surface and the wall surface of the pocket can be appropriately cut by the curved portion of the radius end mill.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic side view of an embodiment of a machine tool 1 that performs pocket-shaped machining on a workpiece W using the “pocket cutting method by an end mill” of the present invention. 2 shows a perspective view of the machine tool 1 shown in FIG. 1 as viewed from the right rear (the cover 30 is not shown). In all drawings in which the X axis, the Y axis, and the Z axis are described, the Y axis indicates the vertically upward direction, the Z axis indicates the horizontal direction, and the direction in which the end mill T cuts into the workpiece W. The axis indicates the horizontal direction orthogonal to the Z axis.

● [Configuration of machine tool 1 (FIGS. 1 and 2)]
The machine tool itself can use the existing machine tool 1 as described below. The present invention is characterized by a feed method (cutting method) of the end mill T described later.
The end mill T and the tool holder Ta are attached to the main shaft 22. The main shaft 22 is rotated about a main shaft rotation axis parallel to the Z-axis direction by a main shaft rotation drive motor 23. The work W is fixed to a work table 24 fixed on the bed 10.
The spindle rotation drive motor 23 is mounted on the Z-axis slide table 16 and can be reciprocated in the Z-axis direction within the column 12 by the Z-axis drive motor 21.
The spindle rotation drive motor 23, the Z-axis slide table 16, and the Z-axis drive motor 21 are integrated and reciprocated in the Y-axis direction along the Y-axis guide rail 13 by the Y-axis drive motor 20 provided in the column 12. Is possible.
The column 12 can be reciprocated in the X-axis direction along the X-axis guide rail 11 with respect to the bed 10 serving as a base by an X-axis drive motor 19.

The spindle rotation drive motor 23, the Z-axis drive motor 21, the Y-axis drive motor 20, and the X-axis drive motor 19 are controlled based on a control signal from a control device (not shown).
The tool magazine 50 provided above the column 12 accommodates various processing tools (including an end mill T) attached to various tool holders Ta. Based on a control signal from a control device (not shown), the machine tool 1 positions the spindle 22 at a tool change position adjacent to the tool magazine 50 and rotates the magazine in the tool magazine 50 to obtain a desired tool holder Ta. It is possible to automatically determine and replace a machining tool equipped with

Then, the machine tool 1 performs processing while jetting a coolant liquid from a nozzle or the like (not shown) to at least a processing portion of the workpiece W, and discharges chips generated by the processing together with the coolant liquid, and recovers the coolant liquid containing the chips. It collect | recovers from the hole 10A. An inclined surface 10B is provided around the coolant recovery hole 10A, and the coolant liquid that has flowed down is collected in the coolant recovery hole 10A. The machine tool 1 is surrounded by a cover 30 for preventing the sprayed coolant liquid from splashing around.
As shown in FIG. 2, the coolant tank 60 is integrally formed with a storage portion 65 inserted into the bed 10 and a discharge tank portion 64.
The housing portion 65 is provided with a recovery hole 60K through which coolant liquid containing chips flows, and a part of the conveyor 61 that transports the chips contained in the coolant liquid to the chip discharge port 66 is housed. Further, in the discharge tank section 64, the remaining portion of the conveyor 61 that conveys the chips to the chip discharge port 66, the conveyor drive motor 62 that drives the conveyor 61, and the chip discharge port 66 that discharges the chips separated from the coolant liquid. And a pump 63 for sucking out a coolant liquid from which chips are separated.

● [Appearance of end mill T (Fig. 3)]
FIG. 3A shows an example of the appearance of a flat end mill T in which the boundary between the bottom surface Mt of the tip and the tool side surface Ms is substantially perpendicular, and FIG. 3B shows the bottom Mt of the tip and the tool The example of the external appearance of the radius end mill T which has the curved part Bw in which the boundary part with the side surface Ms was formed in circular arc shape is shown. In addition, the end mill T can also divert the existing end mill T together with the machine tool 1.
The flat end mill T is provided with a blade Br extending from the center Tc of the tip of the substantially cylindrical tool to the outer periphery of the tip, and further from the outer periphery of the tip toward the rear end of the tool side face Ms.
The blade Br of the radius end mill T is also provided in the same manner, and a curved portion Bw is provided at a boundary portion between the bottom surface Mt and the tool side surface Ms of the blade Br. In the case of the radius end mill T, the curved portion Bw is included in the bottom surface Mt and also included in the tool side surface Ms.
In the description of the present embodiment, when the end mill is moved in the axial direction of the tool rotation axis TZ, the portion to be cut is set as the bottom surface Mt, and the target is obtained when the end mill is moved in the direction orthogonal to the tool rotation axis TZ. A portion to cut is a tool side surface Ms.
The blade provided on the bottom surface Mt is referred to as a bottom blade, and the blade provided on the tool side surface Ms is referred to as a side blade. Therefore, in the case of a radius end mill, the blade of the curved portion Bw is a bottom blade and a side blade.

[Pocket cutting method by end mill T in the first embodiment (FIGS. 4 and 5)]
In the pocket cutting method using the end mill in the first embodiment, in the finishing cutting of the pocket Po where the bottom surface finishing allowance Rt and the wall surface finishing allowance Rk are left, first, the corner cutting allowance Cn shown in FIG. The removed bottom surface finishing allowance Rt is cut in the first cutting process, and then the wall surface finishing allowance Rk including the corner removing allowance Cn is cut in the second cutting process (see FIG. 5).
The bottom finishing allowance Rt is the allowance remaining along the bottom surface of the pocket Po (the surface farthest from the opening of the pocket Po), and the wall finishing allowance Rk is the wall surface of the pocket Po (opening of the pocket Po). This is the machining allowance remaining along the surface adjacent to the part. Further, a machining allowance at a position where the bottom surface finishing allowance Rt and the wall surface finishing allowance Rk overlap is defined as a corner machining allowance Cn.
In the following description, an example using a flat end mill will be described.

[First cutting step]
First, a first cutting process for cutting only the bottom surface finishing allowance Rt excluding the corner removing allowance Cn will be described with reference to FIG.
4B is a view of the pocket Po as viewed from the opening direction, and FIG. 4A is a cross-sectional view taken along line AA in FIG. 4B.
As shown in FIG. 4A, with respect to the end mill T that rotates about the tool rotation axis TZ, the end mill T is located near the center of the bottom surface of the pocket Po so that the bottom surface of the pocket Po is perpendicular to the tool rotation axis TZ. The pocket Po and the end mill T are arranged so that the front end of is located.
Then, the end mill T is cut relative to the pocket Po in the axial direction of the tool rotation axis TZ by a bottom surface finishing depth S [1], and the end mill T is cut using the surface (bottom edge) of the tip portion. Cut.
Subsequently, as shown in FIG. 4B, the end mill T is moved from the cut position relative to the pocket Po in a direction perpendicular to the tool rotation axis TZ (to draw a spiral). Without cutting the wall finishing allowance Rk, the bottom finishing allowance Rt for the bottom finishing depth (in this case, the depth of S [1]), excluding the corner allowance Cn, The bottom flat portion cutting is performed using the tool side surface (side blade) of T.

Then, until the bottom surface finish shape position is reached (until the bottom surface finish allowance Rt excluding the corner allowance Cn is eliminated), the above-described cutting and bottom flat portion cutting are sequentially repeated to remove the corner allowance Cn. Only the bottom finishing allowance Rt is cut first.
The hatched portion in FIG. 4C is the bottom finishing allowance Rt excluding the corner allowance Cn. The corner cutting allowance Cn is cut in the second cutting step as the wall finishing allowance Rk.

[Second cutting step]
Then, the 2nd cutting process which cuts the wall surface finishing allowance Rk including the corner allowance Cn is demonstrated using FIG.
FIG. 5B is a view of the pocket Po as viewed from the opening direction, and FIG. 5A is a cross-sectional view taken along the line BB in FIG.
After the first cutting step, first, as shown in FIG. 5A, the end mill T [1] is inserted so that the end portion of the end mill T is inserted from the inlet portion of the pocket Po by the wall finishing depth L [1]. ] And a pocket Po are arranged. Then, the end mill T [1] is moved relative to the pocket Po in a direction perpendicular to the tool rotation axis TZ and along the inner wall of the pocket Po, so that the wall finishing for the wall finishing depth in the pocket Po is performed. Wall surface contour cutting is performed by cutting the machining allowance Rk [1] (see FIG. 5C) using the tool side surface (side blade) of the end mill T [1].

After wall surface contour cutting for cutting the wall finishing allowance Rk [1], the end mill T is once moved in a direction perpendicular to the tool rotation axis TZ to be separated from the inner wall of the pocket Po, and the tip of the end mill T [1] is Further, only the wall finishing depth L [2] is inserted (see end mill T [2] in FIG. 5A). Then, the end mill T [2] is moved relative to the pocket Po in the direction perpendicular to the tool rotation axis TZ and along the inner wall of the pocket Po to newly perform wall surface contour cutting, and a new wall finishing. Wall surface contour cutting for cutting the wall surface finishing allowance Rk [2] (see FIG. 5C) for the depth using the tool side surface (side blade) of the end mill T [2] is performed. This operation is sequentially repeated until the bottom surface of the pocket Po (the position of the finished shape on the bottom surface) is reached.
In the example of FIG. 5, the bottom surface of the pocket Po (position of the finished shape) is reached by wall surface contour cutting that cuts the wall surface finishing allowance Rk [3] using the tool side surface (side blade) of the end mill T [3]. Therefore, the second cutting process is completed by cutting the wall surface finishing allowance Rk [3].
Before inserting the end mill by the wall finishing depth L [n], the distance to the bottom surface of the pocket Po is compared with the wall finishing depth L [n], and the end mill T is inserted by the smaller distance. If it goes, the collision between the end mill T and the bottom surface of the pocket Po can be avoided.

● [Pocket cutting method by end mill T in the second embodiment]
In the second embodiment, the cutting order of the bottom surface finishing allowance Rt and the wall surface finishing allowance Rk is reversed with respect to the first embodiment. That is, in the first cutting process, the wall surface finishing allowance Rk excluding the corner allowance Cn is cut first, and then in the second cutting process, the bottom surface finishing allowance Rt including the corner removing allowance Cn is obtained. To cut.

[First cutting step]
In the first cutting process, first, with respect to the end mill T that rotates about the tool rotation axis TZ, the bottom surface of the pocket Po is perpendicular to the tool rotation axis TZ, and the end portion of the end mill extends from the entrance of the pocket Po. The end mill T [1] and the pocket Po are arranged so that only the wall surface finishing depth L [1] is inserted (see FIG. 5A). Then, the end mill T [1] is moved relative to the pocket Po in a direction perpendicular to the tool rotation axis TZ and along the inner wall of the pocket Po, so that the wall finishing for the wall finishing depth in the pocket Po is performed. Wall surface contour cutting is performed by cutting the machining allowance Rk [1] (see FIG. 5C) using the tool side surface (side blade) of the end mill T [1].
Hereinafter, the wall finishing allowance Rk [2] and the wall finishing allowance Rk [3] (in the second embodiment, excluding the corner removing allowance Cn) are cut, and the wall finishing allowance excluding the corner removing allowance Cn is removed. Only Rk is cut. The corner machining allowance Cn is left as the bottom finishing allowance Rt and is cut in the second cutting process.

[Second cutting step]
Next, the second cutting process will be described.
After cutting the wall surface finishing allowance Rk excluding the corner allowance Cn described above, the end mill T is positioned near the center of the bottom surface of the pocket Po and relative to the pocket Po in the axial direction of the tool rotation axis TZ. Is cut by a bottom finishing depth S [1], and cutting is performed using the surface (bottom edge) of the tip of the end mill T.
Subsequently, as shown in FIG. 4 (B), the end mill T is moved relative to the pocket Po in a direction perpendicular to the tool rotation axis TZ from the cut position (to draw a spiral). Cutting is performed so that the bottom surface flat portion is cut by using the tool side surface (side blade) of the end mill T to the position of the finished shape of the wall surface (in the second embodiment, including the corner allowance Cn). Cutting). That is, the bottom finishing allowance Rt including the corner removing allowance Cn for the finishing depth S [1] is cut.
Then, the above cutting and bottom flat portion cutting are sequentially repeated until the position of the finished shape on the bottom surface is reached.

In the first embodiment and the second embodiment described above, by using the end mill T, in the first cutting step, the bottom surface finishing allowance Rt excluding the corner allowance Cn or the corner removal is obtained. Only one machining allowance of the wall surface finishing allowance Rk excluding the allowance Cn is cut first.
Then, in the second cutting step, the remaining machining allowance including the corner machining allowance Cn is cut, and the bottom surface finishing allowance Rt excluding the corner machining allowance Cn and the wall surface finishing allowance excluding the corner machining allowance Cn. Rk is cut separately without simultaneously cutting.
As a result, by changing the cutting method using an existing end mill, in the cutting of the corner removal allowance Cn portion without increasing the cutting resistance, the feed rate is higher than before and the accuracy is equal to or higher than the conventional one. Can be cut.
In the corner removal allowance Cn portion where the feed rate is the smallest, a feed rate higher than the conventional one can be obtained, so that the feed rate of the entire cutting process does not become unnecessarily small with this feed rate. Therefore, the entire processing time is shortened and the processing efficiency can be improved.

In the first embodiment and the second embodiment described above, the bottom edge of the end mill T (in this case, the curved portion) is cut in the boundary portion (corner portion) between the bottom surface and the wall surface of the pocket Po. Cutting is performed without increasing the cutting resistance by cutting so as not to use both of the blades (except the blade of Bw) and the side blade (excluding the blade of the curved portion Bw in this case).
Thereby, the feed rate of the whole cutting process is not reduced as in the prior art, and the processing efficiency can be improved.
In the description of the present embodiment, the end mill T is moved in the X axis direction, the Y axis direction, and the Z axis direction with respect to the workpiece W. However, the workpiece W is moved in the X axis direction and the Y axis direction with respect to the end mill T. , It can also be configured to move in the Z-axis direction. Therefore, the end mill T moves relative to the workpiece W in the X axis direction, the Y axis direction, and the Z axis direction.

The “pocket cutting method by the end mill” of the present invention is not limited to the processing, the cutting method, etc. described in the present embodiment, and various modifications, additions, and deletions are possible without departing from the scope of the present invention. . Further, the machine tool that uses the “pocket cutting method by the end mill” of the present invention is not limited to the machine tool 1 shown in the examples of FIGS. 1 and 2.
The end mill T used in the method of cutting the pocket Po by the end mill T described in the present embodiment is not limited to the flat end mill and the radius end mill shown in FIG. 3, and various end mills can be used.
In addition, when the boundary between the wall surface and the bottom surface of the pocket is connected in a smooth arc shape, the arc shape can be appropriately formed by using a radius end mill having a curved portion having a curvature corresponding to the arc shape. Can do.
The shape of the pocket Po is not limited to the cylindrical space.

It is a side view explaining one embodiment of machine tool 1 which cuts a pocket using "the pocket cutting method by an end mill" of the present invention. It is the perspective view which looked at the machine tool 1 from the right rear. It is a figure explaining the example of the external appearance (FIG. 3 (A)) of the flat end mill T, and the external appearance (FIG. 3 (B)) of the radius end mill T. It is a figure explaining the 1st cutting process (The method of cutting bottom finishing allowance Rt except corner removal allowance Cn) in the pocket cutting method by end mill T. FIG. It is a figure explaining the 2nd cutting process in the pocket cutting method by end mill T (method of cutting wall surface finishing allowance Rk including corner removing allowance Cn). It is a figure explaining the conventional pocket cutting method by an end mill.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Machine tool 10 Bed 11 X-axis guide rail 12 Column 13 Y-axis guide rail 16 Z-axis slide table 19 X-axis drive motor 20 Y-axis drive motor 21 Z-axis drive motor 22 Spindle 23 Spindle rotation drive motor 24 Worktable 50 Tool magazine 60 Coolant tank 61 Conveyor 62 Conveyor drive motor 63 Pump 64 Discharge tank unit 65 Storage unit 66 Chip discharge port T End mill TZ Tool rotation axis W Work Cn Corner removal allowance Rt Bottom finish allowance Rk Wall finish allowance Po pocket

Claims (4)

Using an end mill that is provided with a blade that extends from the center of the tip of the substantially cylindrical tool to the outer periphery of the tip, and further from the outer periphery of the tip toward the rear end of the side of the tool, In the pocket cutting method by the end mill, which finish-cuts the pocket where the finishing allowance is left in each of the
The pocket finishing allowance includes a bottom finishing allowance along the bottom surface, a wall finishing allowance along the wall surface, and a corner allowance where the bottom finishing allowance and the wall finishing allowance overlap. And consist of
The pocket and the end mill are arranged so that the tool rotation axis is orthogonal to the bottom surface of the pocket,
Using the end mill,
In the first cutting step, the bottom finishing allowance excluding the corner allowance or the wall finishing allowance excluding the corner allowance is cut first.
In the second cutting step following the first cutting step, cutting the remaining machining allowance including the corner machining allowance,
Cutting the bottom surface finishing allowance excluding the corner allowance and the wall surface finishing allowance excluding the corner allowance separately without simultaneously cutting,
Pocket cutting method by end mill. A pocket cutting method using an end mill according to claim 1,
In the first cutting step,
A tip end of the end mill is disposed near the center of the bottom surface of the pocket, and the end mill is cut relative to the bottom surface of the pocket by a bottom finish depth relative to the axial direction of the tool rotation axis. Perform incision cutting to cut using the bottom blade provided on the surface,
Subsequently, from the cut position, the end mill is moved relative to the pocket in a direction perpendicular to the tool rotation axis, and the bottom surface finishing depth is cut without cutting the wall surface finishing allowance. The bottom surface finishing allowance excluding the corner removal allowance is cut using a side face blade provided on the tool side surface of the end mill, and the bottom flat portion is cut.
The incision cutting and the bottom flat portion cutting are repeated until the bottom surface finishing allowance excluding the corner removal allowance is eliminated, and only the bottom surface finishing allowance excluding the corner removal allowance is preceded by the wall surface finishing allowance. Cut into
In the second cutting step,
The end mill and the pocket are arranged so that the end of the end mill is inserted by the wall finishing depth from the entrance of the pocket,
By moving the end mill relative to the pocket in a direction perpendicular to the tool rotation axis and along the inner wall of the pocket, a wall finishing allowance for the wall finishing depth in the pocket is obtained. Wall surface contour cutting using the side blades of
After the wall surface contour cutting, the end mill end is further inserted by the wall surface finishing depth, and the wall surface contour cutting is performed to newly cut the wall surface finishing allowance for the wall surface finishing depth. Until it reaches the bottom surface, and cut the wall finishing allowance including the corner allowance,
Pocket cutting method by end mill. A pocket cutting method using an end mill according to claim 1,
In the first cutting step,
The end mill and the pocket are arranged so that the end of the end mill is inserted by the wall finishing depth from the entrance of the pocket,
The end mill is moved relative to the pocket in a direction perpendicular to the tool rotation axis and along the inner wall of the pocket, and the wall surface finishing depth in the pocket is cut without cutting the bottom surface finishing allowance. Perform wall surface contour cutting to cut the wall surface finishing allowance excluding the corner allowance using a side blade provided on the side surface of the end mill,
After the wall surface contour cutting, the end mill end is inserted further by the wall surface finishing depth, and the wall surface finishing is performed by newly cutting the wall surface contour line and excluding the corner removal allowance for the wall surface finishing depth. The operation of cutting the machining allowance is sequentially repeated until the bottom of the pocket is reached, and only the wall surface finishing allowance excluding the corner machining allowance is cut before the bottom finishing allowance,
In the second cutting step,
A tip end of the end mill is disposed near the center of the bottom surface of the pocket, and the end mill is cut relative to the bottom surface of the pocket by a bottom finish depth relative to the axial direction of the tool rotation axis. Perform incision cutting to cut using the bottom blade provided on the surface,
Subsequently, from the cut position, the end mill is moved relative to the pocket in a direction perpendicular to the tool rotation axis, and the bottom finish including the corner machining allowance for the bottom finish depth is included. The bottom allowance is cut using the side blade of the end mill, and the bottom flat portion is cut.
Repeating the cutting and the bottom flat portion cutting until the bottom finishing allowance including the corner allowance is eliminated, and cutting the bottom finish allowance including the corner removing allowance,
Pocket cutting method by end mill. A pocket cutting method using an end mill according to any one of claims 1 to 3,
The shape of the boundary between the wall surface and the bottom surface of the pocket is an arc shape that smoothly connects the wall surface and the bottom surface,
Cutting using a radius end mill in which a curved portion having a curvature corresponding to the arc shape is provided on a blade near the outer periphery of the tip portion,
Pocket cutting method by end mill.

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