JP4412890B2 - Throwaway end mill - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a throw-away end mill used as a rotary tool, in particular, an end mill with a bottom blade capable of three-dimensional cutting, and a throw-away tip attached thereto.
[0002]
[Prior art]
In the throw-away end mill capable of three-dimensional cutting, shoulder machining and grooving that can be machined with a normal end mill that does not have a cutting edge to the end mill axis center with only the outer peripheral edge as the form of machining. In addition, by having a cutting edge to the end mill axis, machining that sinks obliquely to the work material and machining that sinks vertically in the axial direction like drilling are possible. . In such a three-dimensional end mill, a throwaway tip having a substantially parallelogram has been conventionally used. 4 to 6 show a three-dimensional end mill as a conventional example. 4A and 4B show a conventional throw-away tip 17, in which FIG. 4A is a plan view, FIG. 4B is a short side view, and FIG. 4C is a long side view. FIG. 5 is a side view of the end mill with the conventional throw-away tip 17 attached to the end mill body 18, and FIG. 6 is a bottom view of FIG. As shown in FIG. 5, the first tip is attached to the end mill body 18 with the long side cutting edge 19 as the outer peripheral edge and the short side cutting edge 20 as the bottom edge, and the second tip has the long side cutting edge 19 as the bottom edge. As a bottom blade, a short edge 20 is attached to the end mill body 18 as an outer peripheral blade. (For example, refer to Patent Document 1.)
In the conventional tip, the outer peripheral blades of the first and second tips are linear over the entire length, and the tip and rear end and the tip and rear end of the second tip outer peripheral blade have the same or substantially the same processing diameter. It was an arrangement.
[0003]
[Patent Document 1]
JP-A-8-323527 [0004]
[Problems to be solved by the invention]
However, the conventional throw-away end mill has a problem that when it is processed in the high feed region when performing end mill processing, abnormal vibration is likely to occur and it is difficult to increase the processing efficiency.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a throw-away end mill according to claim 1 is provided with a short-side cutting edge at a cross edge of a side surface and an upper surface of a tip body having a polygonal plate shape at a tip portion of a substantially cylindrical tool body. The first tip is provided on a tool body with the long side cutting edge as an outer peripheral blade and the short side cutting edge as a bottom blade, with the first and second tips provided with a long side cutting edge, The second tip is a throw-away end mill attached to the tool body with the long side cutting edge as a bottom blade and the short side cutting edge as an outer peripheral blade, and the outer peripheral blade of the first tip has a convex shape. In addition, the convex position of the convex edge of the outer peripheral blade of the first tip and the end of the outer peripheral blade of the second tip farther from the bottom blade are made equal in axial position with respect to the axis of the tool body, and Equal distance from the axis position Further characterized in that the total length of the peripheral cutting edge of said first of said from the tip of the outer peripheral edge of the chip convex top to said second chip, and a straight cutting edge.
[0006]
According to such a configuration, Rutotomoni can improve the deflection blades and corresponding parts of the peripheral cutting edge and the outer peripheral edge of the first chip of the second chip, peripheral cutting edge and the first chip to the second chip The corresponding part of the outer peripheral blade can be formed into a two-blade shape with high accuracy. As a result, when end milling is performed, abnormal vibration hardly occurs even when processing is performed in a high feed region, and processing efficiency can be improved. it can.
[0007]
As in the conventional tip, the outer peripheral blades of the first and second tips are linear over the entire length, and the processing diameters of the front and rear ends of the first and second tips are the same or substantially the same. In the case of the tip arrangement, except for the tip of the outer peripheral blade, the distance from the axial position at the same axial position of the tool body is different between the first and second chips, and the blade runout is poor. Further, since the degree of blade run-out varies depending on the axial position, it is considered that the balance of cutting stress is deteriorated, and as a result, abnormal vibration is likely to occur.
[0008]
Also, the throw-away end mill of claim 2 is the peripheral cutting edge of the front Symbol first chip, that the arc-shaped cutting edge and the straight cutting edge are formed successively farther from the end cutting edge than before Kitotsuitadaki Features.
[0009]
According to this configuration, by connecting two linear cutting blades directly via an arcuate cutting blade, there is no pin angle on the outer peripheral blade, and a reduction in the cutting edge strength of the outer peripheral blade is suppressed. it can be.
[0010]
When the corresponding part of the outer peripheral blade of the second tip and the outer peripheral blade of the first tip is an arc-shaped cutting blade, it is difficult to measure the shape accuracy of the arc-shaped cutting blade, and the shape accuracy is increased. Is difficult to correct. Therefore, it is difficult to form a complete two-blade shape.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3 show an embodiment of the present invention. FIG. 1A is a plan view of a throw-away tip 1 according to this embodiment, FIG. 1B is a side view of a short side, and FIG. 2 is a side view of the end mill, FIG. 2 is a side view of the end mill in a state where the throw-away tip 1 of this embodiment is mounted on the end mill main body 14, and FIG. 3 is a bottom view of FIG.
[0012]
In FIG. 1, the throw-away tip 1 according to the present embodiment is provided with a short-side cutting edge 6 and a long-side cutting edge 7 on the intersection ridge formed by the side surface 4 and the upper surface 5 of the chip body having a polygonal plate shape. A corner portion where the long side cutting edge 7 and the short side cutting edge 6 intersect is connected by an arc-shaped ridge line, and the long side cutting edge 7 and the short side cutting edge 6 are acute angles. The side that intersects at is used as the corner cutting edge 8.
[0013]
In the throw-away tip 1, the long edge cutting edge 7 has a convex shape that suppresses blade runout as will be described later. In the present embodiment, the long side cutting edge 7 has a linear cutting edge 7a from one end to the convex top 7b, and the long side cutting edge 7 on the other side of the convex top 7b has an arcuate cutting edge 7c. A linear cutting edge 7d is sequentially provided.
[0014]
The throw-away tip has a constant cutting edge height with respect to the seating surface 9 in the long-side cutting edge 7 in a side view, but the cutting edge height in the vicinity of the center of the short-side cutting edge 6 is higher than both ends. Is also low and has an arcuate concave curve. Further, a screw hole 10 for tip screwing penetrating to the seating surface 9 is formed in the center portion of the chip upper surface 5. On the top surface 5 of the chip, a rake surface 11 having a positive rake angle is continued from the long side cutting edge 7, a groove bottom surface 12 parallel to the seating surface 9, and in the vicinity of the screw hole 10 from the groove bottom surface 12. A raised breaker projection 13 is formed.
[0015]
Moreover, while making the said short side cutting edge 6 into the concave shape which becomes low as it approaches the center part by the side view by the side of the said short side cutting edge 6, here, the breaker protrusion part formed along the short side cutting edge 6 here The 13 breaker walls 13a have a convex shape that becomes higher as approaching the center. Further, the breaker wall 13a has a convex shape that approaches the short edge cutting edge 6 as it approaches the center of the chip body in plan view.
[0016]
Next, FIG. 2 is a side view of the end mill with the throw-away tip 1 mounted on the end mill body 14, and FIG. 3 is a bottom view of FIG. Here, the throw-away end mill includes a first tip 15 and a second tip 16, at least two tips, and the first tip 15 has a long side cutting edge 7 as an outer peripheral edge 32 and a short side cutting. The blade 6 is attached to the end mill body 14 as a bottom blade 30, and the second chip 16 is attached to the end mill body 14 using a long edge cutting edge as a bottom edge 31 and a short edge cutting edge as an outer peripheral edge 33. .
[0017]
Here, as the first chip 15, the above-described throw-away chip 1 shown in FIG. 1 is used.
In this throw-away end mill, the outer peripheral edge 32 of the first tip 15 has a convex shape that suppresses blade runout, and the rear end 33b of the outer peripheral edge 33 of the second tip 16 (the end far from the bottom edge 31). The axial positions of the tool body 14 and the convex crests 7b of the outer peripheral edge 32 of the first tip 15 are made equal, and the distances d1 and d2 from the axial positions are made equal.
[0018]
Here, the distances d1 and d2 from the axis position being equal include the case where there is an error of 0.04 or less.
[0019]
According to such a configuration, it is possible to improve the blade runout between the outer peripheral blade 33 of the second tip 16 and the corresponding portion of the outer peripheral blade 32 of the first tip 15, and as a result, when performing end milling, high feed Even if processing is performed in the region, abnormal vibration hardly occurs, and processing efficiency can be improved.
[0020]
Moreover, in the present embodiment, the throw-away end mill is configured so that the outer peripheral edge 33 of the second tip 16 is a linear cutting edge over the entire length, and the tip 32a (bottom edge 30) of the outer peripheral edge 32 of the first tip 15 is used. A straight cutting edge 7a is formed from the end closer to the convex crest 7b to the outer peripheral edge 32 on the rear end side (the side farther from the bottom edge 30) than the convex crest 7b. The cutting blades 7d are sequentially provided.
[0021]
In the outer peripheral blade 32 of the first tip 15, the two linear cutting blades 7 a and 7 d are not directly connected but connected via the arcuate cutting blade 7 c, so that there is no pin angle on the outer peripheral blade 32. Moreover, the fall of the cutting blade strength of the outer periphery blade 32 can be suppressed. Further, the outer peripheral edge 33 of the second tip 16 is a linear cutting edge over the entire length, and the linear cutting edge 7a is from the tip 32a of the outer peripheral edge 32 of the first tip 15 to the convex apex 7b. Accordingly, the corresponding portions of the outer peripheral blade 33 of the second chip 16 and the outer peripheral blade 32 of the first chip 15 can be formed into a two-blade shape. As a result, the effect of making the abnormal vibration difficult to occur can be further enhanced.
[0022]
As mentioned above, although embodiment of this invention was illustrated, this invention is not limited to the said embodiment. It goes without saying that the present invention can be in any form without departing from the object of the invention.
[0023]
【The invention's effect】
As described above, according to the throw-away end mill of the first aspect, a short-side cutting edge and a long edge are formed on the tip of the substantially cylindrical tool body at the cross edge of the side surface and the upper surface of the polygonal plate body. The first tip is attached to a tool body with the long side cutting edge as an outer peripheral blade and the short side cutting edge as a bottom blade. The tip 2 is a throw-away end mill attached to the tool body with the long side cutting edge as a bottom blade and the short side cutting edge as an outer peripheral edge, and the outer peripheral edge of the first tip has a convex shape. The convex tip of the outer peripheral blade of the first tip having a convex shape and the end of the outer peripheral blade of the second tip farther from the bottom blade are made equal in axial position with respect to the axis of the tool body, and equal distances from the axis position, further And a total length of peripheral cutting edge of said first of said from the tip of the outer peripheral edge of the chip convex top to said second chip, since it has a straight cutting edge, the second chip peripheral cutting edge and the first can improve the deflection blades and corresponding parts of the outer peripheral edge of the chip Rutotomoni, can the peripheral cutting edge and a corresponding portion of the outer peripheral edge of the first chip of the second chip and precisely two blade-shaped As a result, when performing the end milling, perform the processing at high feed region hardly occurs abnormal vibration, thereby improving the processing efficiency.
[0024]
Also, the throw-away end mill of claim 2 is the peripheral cutting edge of the front Symbol first chip, before the said from the bottom edge farther that are sequentially formed an arcuate cutting edge and straight cutting edge than Kitotsuitadaki By connecting two linear cutting blades directly via an arcuate cutting blade, there is no pin angle on the outer peripheral blade, and a reduction in the cutting edge strength of the outer peripheral blade can be suppressed .
[Brief description of the drawings]
FIG. 1 is a schematic view of a throw-away tip of the present invention, (a) a plan view, (b) a short-side side view, and (c) a long-side side view.
FIG. 2 is a side layout view when the throw-away tip of FIG. 1 is mounted on a tool body.
FIG. 3 is a bottom plan view of FIG. 2;
4A and 4B are schematic views of a conventional throw-away tip, where FIG. 4A is a plan view, FIG. 4B is a short side view, and FIG. 4C is a long side view.
FIG. 5 is a side layout diagram when the throw-away tip of the conventional example of FIG. 4 is mounted on a tool body.
6 is a bottom plan view of FIG. 5. FIG.
[Explanation of symbols]
1: Throw away tip 2: Short side surface 3: Long side surface 4: Side surface 5: Top surface 6: Short edge cutting edge 7: Long edge cutting edge 7a: Straight cutting edge 7b: Convex apex 7c: Arc-shaped cutting Blade 7d: Linear cutting blade 8: Corner cutting blade 9: Seating surface 10: Screw hole 11: Rake surface 12: Groove bottom surface 13: Breaker projection 13a: Breaker wall 14: End mill body 15: First tip 16: First 2 tip 30: first tip bottom blade 31: second tip bottom blade 32: first tip outer peripheral blade 32a: first tip outer peripheral blade tip 32b: first tip outer peripheral blade Rear end 33: second tip outer peripheral blade 33a: second tip outer peripheral blade tip 33b: second tip outer peripheral blade rear end d1, d2: distance from the axial position

Claims (2)

At the tip of the substantially cylindrical tool body, there are provided first and second chips provided with a short edge and a long edge at the crossing ridge between the side surface and the upper surface of the polygonal plate body. The first tip is attached to the tool body with the long side cutting edge as the outer peripheral edge and the short side cutting edge as the bottom edge, and the second tip is the short edge with the long side cutting edge as the bottom edge. A throw-away end mill attached to the tool body with a side cutting edge as the outer peripheral edge,
The outer edge of the first tip has a convex shape, and the convex tip of the outer peripheral blade of the first tip made convex and the end of the outer peripheral blade of the second tip farther from the bottom blade, Equalizing the axial position with respect to the axis of the tool body and equalizing the distance from the axial position;
Further, the throw-away end mill is characterized in that a straight cutting edge is used from the tip of the outer peripheral edge of the first tip to the convex top and the entire length of the outer peripheral edge of the second tip. 2. The throwaway end mill according to claim 1, wherein an arcuate cutting edge and a linear cutting edge are sequentially formed on a side farther from the bottom edge than the convex top in the outer peripheral edge of the first tip.

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