JP3823226B2 - Cutting tools - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a cutting tool that uses one type of throw-away tip for a work material in which a pilot hole is drilled, and can simultaneously perform counterbore drilling and chamfering.
[0002]
[Prior art]
As shown in FIG. 9, a conventional method for performing counterboring and chamfering on a work material with a prepared pilot hole is first cut the work material H with a prepared pilot hole J (see FIG. 9A). ) Using the tool T1 to machine the counterbore W (see FIG. 9B), and then using the tool T2 to chamfer the pilot hole J at the bottom of the counterbore hole (FIG. 9C). In general, a method of performing chamfering (see FIG. 9D) of the counterbore hole mouth using the tool T3 is generally performed.
[0003]
However, regarding a cutting tool capable of simultaneously performing counterboring and chamfering, there is an end mill or the like that is integrally formed in a machining curve shape, but there is no tool that uses a throw-away tip.
However, since a cutting tool capable of performing various types of processing using a throw-away tip is disclosed, the following three examples are shown for reference.
[0004]
The first example is a tool that uses a composite tool with multiple tools and saves the trouble of changing tools and improves machining efficiency. One tool can perform multiple types of turning and drill / milling. A small-diameter composite tool that can be performed is shown (for example, see Patent Document 1).
[0005]
The second example uses two throwaway tips of the same shape formed in a substantially isosceles trapezoidal shape at the end of the end mill, and the two corners overlap with the corner portion where the bottom cutting edge and the outer peripheral cutting edge intersect It becomes a specification and the corner part in each throw-away tip is prevented from being greatly worn or chipped, and even when drilling or inclined cutting in addition to grooving, stable cutting can be performed over a long period of time. Such an end mill is shown (for example, see Patent Document 2).
[0006]
The third example shows a throw-away tip that is formed in a substantially drum-shaped plate shape and has a total of four cutting edges, one pair in the diagonal direction of the upper and lower surfaces (see, for example, Patent Document 3). .
[0007]
[Patent Document 1]
JP 2002-154007 A (page 2, column 2, lines 31 to 41, FIGS. 4 to 6)
[Patent Document 2]
JP-A-2001-212712 (page 2, column 1, lines 23 to 28 and page 3, column 3, lines 40 to 46, FIGS. 7 and 8)
[Patent Document 3]
Japanese Unexamined Patent Publication No. 07-237027 (first page summary and third page, third column, lines 42 to 47, FIG. 1)
[0008]
[Problems to be solved by the invention]
However, in conventional cutting tools, using a throw-away tip, counterbore drilling is performed on the work material in which the pilot hole has been drilled, chamfering to the pilot hole at the bottom of the counterbore hole, and chamfering of the counterbore hole mouth. There is a problem that a cutting tool capable of performing processing simultaneously is not provided.
Therefore, an object of the present invention is to provide the above-described cutting tool using two throw-away tips that enable the above-described three processing with one type of throw-away tip.
[0009]
[Means for Solving the Problems]
In a cutting tool for counterboring and chamfering using a throw-away tip on a work material with a prepared drilled hole, the lower right vertex of a square ABCD having a tip thickness r and an inscribed circle diameter k is A trapezoid EFCG having a lower right vertex C, a trapezoid EFCG portion having a left base angle θ (0 ° <θ <90 °), a right base angle 90 °, an upper base m, and a height n is removed from the square ABCD. Is rotated clockwise by 90 °, the same trapezoid shape is removed from each vertex D, A, and B as in vertex C, and the formed figure is defined as a rake face (51). A throw-away tip having a flank (52) formed so as to have a clearance angle α from the entire periphery and a mounting hole (53) provided at the center of the inscribed circle is attached to a seat ( 31a ) bottom surface ( 32a ) and body The above-mentioned problems have been solved by providing a cutting tool that can be mounted on the bottom surface ( 32b ) of the mounting seat ( 31b ) formed on the upper portion of the steel plate and at the same time perform counterboring and chamfering at two locations. is there.
[0010]
【The invention's effect】
According to the present invention, a single cutting tool to which two types of throw-away tips are attached is used to counter bore a workpiece with a pilot hole drilled, chamfering to a pilot hole at the bottom of the counterbore hole, and a seat. It becomes possible to perform chamfering of the hole hole at the same time,
[0011]
Furthermore, by using two nearly square throwaway tips having four types of cutting edges at four locations, one throwaway tip can be used for the above three locations. Even when the cutting edge is damaged or sharp, it can be replaced with another cutting edge insert, eliminating the need to interrupt the work for a long time, enabling efficient machining and shortening the machining time. It becomes. In addition, the cutting tool of the present invention can be used for counter boring and chamfering of fixed-size bolts, and of course, since the cutting tool can be easily designed and manufactured, specially-designed bolts can be obtained. It can also be used for counterbore processing and chamfering processing of fastening hardware.
[0012]
【Example】
Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the cutting tool 1 of the present invention includes a tip mounting shank 11 and throw-away tips 5 a and 5 b formed from a shaft 12 and a body 3.
[0013]
First, as shown in FIG. 2A, the work material H processed by the cutting tool 1 of the present invention is a material in which a pilot hole J of a pilot hole diameter j is drilled. The processed material R is obtained by processing. As shown in FIG. 2 (b), the first location is counterbore processing P for counterboring hole W with counterbore diameter w and counterbore depth u, and the second location is counterbore. Chamfering depth f1 / beveling chamfering process S of chamfering depth f1 / chamfering angle λ1 to chamfering depth f1 / chamfering angle λ1 of chamfering depth f2 / chamfering angle λ2 This is a counterbore chamfering process V for processing a chamfer.
[0014]
In this embodiment, in the cutting tool 1 used for counterboring and chamfering of a hexagon socket head cap bolt having a diameter of 12 mm (hereinafter referred to as “processing for φ12 hexagon socket head cap bolt”), the pilot hole diameter j is 14 mm. The counterbore hole diameter w is 20 mm, the counterbore depth u is 13 mm, the chamfering depth f1 is 0.5 mm, the chamfering angle λ1 is 45 °, the chamfering depth f2 is 1 mm, and the chamfering angle λ2 is 45 °.
[0015]
In FIG. 2 (b) and FIG. 2 (c), spatial rectangular coordinates are defined as follows, and are used for the following explanation and other figures.
The coordinate origin O is the intersection of the center line 13 of the counterbore W and the pilot hole J and the plane W1 at the bottom of the counterbore W, and the positive direction of the x-axis is the direction in front of the center line 13 passing through the origin O. The positive direction of the y-axis is a direction obtained by rotating the positive x-axis 90 ° counterclockwise when viewed from above the center line 13, and the positive direction of the z-axis is an upward direction of the center line 13.
[0016]
As shown in FIG. 3, the throw-away tip 5a, 5b used in the cutting tool 1 of the present invention has a lower right vertex C of a square ABCD having a tip thickness r and having an inscribed circle diameter k. A trapezoidal EFCG of C, with the left base angle θ (0 ° <θ <90 °), the right base angle 90 °, the top base m, and the height n removed from the square ABCD, and the square ABCD is rotated clockwise. Rotate every 90 ° and remove the trapezoid of the same shape from the vertices D, A, and B as the vertices C to form a rake face 51 and escape from the entire periphery of the rake face 51. A flank 52 is formed on each of the throwaway tips 5a and 5b so as to have an angle α, and a throwaway tip mounting hole 53 is provided at the center of the inscribed circle. In the throw-away tips 5a and 5b used in the processing for φ12 hexagon socket head bolts of this example, the inscribed circle diameter k is 9.525 mm, the upper base m is 2.530 mm, the height n is 1.000 mm, and the left The base angle θ is 43.83 °, the clearance angle α is 15 °, and the thickness r is 3.18 mm.
[0017]
The body 3 is formed in the shape of a straight cylinder with one step. As shown in FIGS. 4 (a) and 4 (c), a chip pocket 30a is formed in the lower part of the body 3, and the chip pocket 30a is attached. A seat 31a, a seat surface 32a cut in parallel to the surface of the mounting seat 31a, a fixing screw hole 38a formed in the seating surface 32a, and two wall surfaces of the seating surface 32a. The restriction side walls 33a and 34a are configured. Further, the chip pocket 30b formed on the upper portion of the body 3 is composed of a mounting seat 31b, a seating surface 32b, a fixing screw hole 38b, and regulating side walls 33b and 34b.
[0018]
As shown in FIGS. 4 (a) and 4 (b), the mounting seat 31a has a rake angle γ when the body 3 in the front view (FIG. 4 (a)) is viewed from the bottom. Is formed. Specifically, when the displacement amount e1 of x and the displacement amount e2 of z are set in the xz plane, the coordinate (x, z) = (e1, −e2) passes, is perpendicular to the xz plane, and is the positive direction of the y axis. A plane U1 rotated clockwise by a rake angle γ when viewed from the side is a mounting seat 31a. Further, the mounting seat 31b is formed in the same manner as the mounting seat 31a when viewed from the rear view (FIG. 4C). However, in detail, since it is the displacement amount e1 of x and the displacement amount e3 of z in the xz plane, it passes through the coordinates (x, z) = (− e1, e3), is perpendicular to the xz plane, and y A plane U2 rotated by a rake angle γ counterclockwise when viewed from the positive direction of the shaft is a mounting seat 31b. In the body 3 used for the machining for φ12 hexagon socket head bolts of this embodiment, the displacement amount e1 is 1.5 mm and the displacement amount e2 is 1.0 mm, but e2 and n indicate the same distance.
[0019]
Subsequently, the throw-away tip 5a seated on the seat surface 32a of the mounting seat 31a formed in the lower part of the body 3 is as shown in FIG. 5 (a), FIG. 3 and FIG.
The angle between the chamfering blade s1 of the throw-away tip 5a and the z-axis coincides with the chamfering angle λ1;
The edge of the chamfering blade v4 of the throw-away tip 5a matches the position of the displacement amount e2,
The length of the perpendicular line extending from the apex G of the throw-away tip 5a to the z-axis is 0.5 times the counterbore diameter w;
In the throw-away tip 5a, the relief side 52 of the chamfering blade v2 and the regulating side wall 33a formed on the wall surface of the seating surface 32a abut, and are formed on the clearance surface 52 of the chamfering blade v3 and the wall surface of the seating surface 32a. That the regulating side wall 34a is in contact,
The rake face 51 and the mounting seat 31a face of the throw-away tip 5a are substantially flush with each other,
When the five points are satisfied, the throw-away tip 5a is attached to the fixing screw hole 38a of the seating surface 32a with the fixing screw 8.
[0020]
Further, the throw-away tip 5b seated on the seat surface 32b of the mounting seat 31b formed on the upper portion of the body 3 is as shown in FIG. 5 (b), FIG. 3 and FIG.
The angle formed by the straight line GL, which is the chamfering blade v1 of the throw-away tip 5b, and the z-axis coincides with the chamfering angle λ2.
The point M on the straight line GL, which is the chamfering blade v1 of the throw-away tip 5b, has a perpendicular distance of 0.5 times the counterbore diameter w,
The apex G of the throw-away tip 5b coincides with the position of the displacement amount e1 of x and the displacement amount e3 of z,
In the throw-away tip 5b, the relief side wall 52b of the chamfering blade v3 and the regulating side wall 33b formed on the wall surface of the seating surface 32b come into contact with each other, and the clearance side 52 of the chamfering blade v4 and the wall surface of the seating surface 32b are formed. That the regulating side wall 34b is in contact,
The rake face 51 and the mounting seat 31b face of the throw-away tip 5b are substantially flush with each other,
When the five points are satisfied, the throw-away tip 5b is attached to the fixing screw hole 38b of the seating surface 32b with the fixing screw 8.
[0021]
The cutting tool 1 configured as described above operates as follows.
When the cutting tool 1 is rotated and lowered to the work material H, the three cutting edges (the chamfering blade s1, the counterbore blade p1, the chamfering blade) formed by the work material H on the throw-away tips 5a and 5b. The processing steps are classified according to which cutting edge in v1) is involved in cutting. Each processing step operates as shown in FIG. 6 (see FIGS. 2 and 3).
[0022]
Processing step 1 (when the cutting edge used is a chamfering edge s1):
When the cutting tool 1 is rotated and lowered, first, the chamfering blade s1 of the throw-away tip 5a attached to the lower part of the cutting tool 1 comes into contact with the peripheral edge of the prepared hole J of the work material H upper surface R1, and the work material Cutting of H is started. When the chamfering blade s1 of the throw-away tip 5a is cut at all portions of the straight line FE, the processing step 1 is finished.
[0023]
Processing step 2 (when the cutting blades used are chamfering blade s1 and counterbore blade p1):
Further, when the cutting tool 1 is lowered, the counterbore blade p1 comes into contact with the upper surface R1 of the work material H, and the work of cutting the counterbore W on the work material H is started. However, also in the machining step 2, the chamfering blade s 1 is cutting the counterbore W of the work material H following the machining step 1. When the chamfering blade v1 of the throw-away tip 5b attached to the upper part of the body 3 of the cutting tool 1 comes into contact with the peripheral edge of the counterbore W on the upper surface R1 of the workpiece H, the processing step 2 ends.
[0024]
Processing step 3 (when the cutting blades used are chamfering blade s1, counterbore blade p1, and chamfering blade v1):
Subsequently, when the cutting tool 1 is lowered, the chamfering blade v1 of the throw-away tip 5b comes into contact with the peripheral edge of the counterbore W on the upper surface R1 of the work material H, and the counterbore chamfering process V starts on the work material H. Is done. In the machining step 3, the counterbore hole machining P and the pilot hole chamfering process S are performed simultaneously with the counterbore mouth chamfering process V. The counterbore mouth chamfering process V is finished when the chamfering to the counterbore mouth reaches the chamfering depth f2, and at this time, the counterbore hole machining P and the pilot hole part chamfering process S are also finished simultaneously.
By the above, all the cutting processes to the workpiece H are complete | finished, and the process completion material R (FIG.2 (b)) is obtained.
[0025]
The relationship between the position of the cutting tool 1 and the finished material R at the end of machining will be described with reference to FIG. 7. The counterbore W is set to the counterbore depth u by the counterbore blade p1 of the throw-away tip 5a. The counterbore processing P to be processed is finished, and the chamfering depth f1 of the counterbore W bottom plane W1 to the peripheral edge J of the counterbore W and the chamfering angle λ1 is prepared by the chamfering edge s1 of the throw-away tip 5a. Is finished, and the counterbore chamfering process V at the chamfering depth f2 and the chamfering angle λ2 is finished by the chamfering blade v1 of the throw-away tip 5b. The above three machining operations are finished at the same time.
[0026]
Therefore, the counterbore P and the counterbore W are formed in the work material H in which the pilot hole J is drilled by one cutting tool 1 to which two types of the throwaway tip 5a and the throwaway tip 5b are attached. It is possible to simultaneously perform the pilot hole chamfering process S and the counterbore base chamfering process V at the base of the base hole J of the bottom plane W1. Further, by using a generally square throw-away tip 5a and a throw-away tip 5b (see FIG. 3) having four types of cutting edges at four locations, one throw-away tip 5a, 5b is attached to the above three locations. Since it can be used for processing, even when the cutting edge is damaged or the sharpness deteriorates during use of the chip, it can be replaced with another cutting edge of the throw-away chip 5a, 5b, so that the work can be performed for a long time. Efficient machining and shortening of machining time can be expected without interruption.
[0027]
In the cutting tool 1 according to the embodiment of the present invention, as shown in FIG. 8, FIG. 3, and FIG.
The variables determined by the counterbore hole W and the chamfer machining dimensions are the pilot hole diameter j, the counterbore hole diameter w, the counterbore depth u, the chamfering angles λ1 and λ2, and the chamfering depths f1 and f2.
The variables determined by the shapes of the throw-away tips 5a and 5b are the inscribed circle diameter k, the upper base m, the height n, and the left base angle θ.
The variables related to the attachment positions of the throw-away tips 5a and 5b to the body 3 are the displacement amounts e1 and e2, the displacement amount e3, the thickness r, the clearance angle α, and the rake angle γ.
The yz coordinates of the center points Q1 and Q2 of the throw-away tips 5a and 5b can be determined by calculation using all the above variables.
[0028]
Therefore, the cutting tool 1 of the present invention can be used for counter boring and chamfering of a fixed-size bolt, and it is possible to easily determine the shape of the body 3 of the cutting tool 1 by calculation from each variable. Therefore, it is not only possible to design and manufacture a custom-made cutting tool 1 that can simultaneously process counterbore and chamfering, but also use it for counterbore and chamfering such as bolts and fasteners with special dimensions. A possible cutting tool 1 can be easily provided.
[Brief description of the drawings]
FIG. 1 is a perspective view of a cutting tool 1 according to an embodiment of the present invention.
FIG. 2 is a front sectional view (a) of a work material H, a front sectional view (b) showing a processing position by a cutting tool 1 of the present invention and coordinate axes of spatial rectangular coordinates, and a plan view showing coordinate axes of spatial rectangular coordinates ( c).
FIG. 3 is an enlarged plan view (a) and an enlarged front view (b) of the throw-away tips 5a and 5b according to the embodiment of the present invention.
FIG. 4 is a partially omitted enlarged front view of the body 3 (a), an explanatory diagram (b) showing the positional relationship of the plane U1 including the mounting seat 31a, a partially omitted enlarged rear view (c) of the body 3 and an attachment It is explanatory drawing (d) which showed the positional relationship of the plane U2 containing the seat 31b.
FIG. 5 is a partially omitted enlarged front view (a) and a partially omitted enlarged rear view (b) showing a body 3 portion to which a throwaway tip 5a, 5b according to an embodiment of the present invention is attached.
FIG. 6 shows a machining step 1 in (a), a machining step 2 in (b), and a machining step 3 in (c) regarding the machining state of the work material H and the positions of the throw-away tips 5a and 5b. It is explanatory drawing.
FIG. 7 is an explanatory diagram showing a positional relationship between the machining end material R and the cutting tool 1 at the end of machining.
FIG. 8 is an explanatory diagram showing the relationship between the attachment positions of the throw-away tips 5a and 5b and the machining locations in the cutting tool 1 according to the embodiment of the present invention.
FIG. 9 is an explanatory view showing the machining steps of conventional spot facing and chamfering.
[Explanation of symbols]
1 Cutting tool
11 Shank for chip mounting
12 axes
13 Centerline
3 Body
30a, 30b Chip pocket
31a, 31b Mounting seat
32a, 32b Bearing surface
33a, 33b Side wall for regulation
34a, 34b Side wall for regulation
38a, 38b Fixing screw hole
5a, 5b Throw away tip
51 Rake face
52 Flank
53 Mounting hole
8 Fixing screws
e1, e2, e3 Displacement
f1, f2 Chamfering depth
H Work material
J Pilot hole
j Pilot hole diameter
k Inscribed circle diameter
m Top bottom
n Height
P Counterbore drilling
p1, p2, p3, p4 counterbore
Q1, Q2 center point
R Finished material
R1 top surface
r Thickness
S Pilot hole chamfering
s1, s2, s3, s4 Chamfering blade
T1, T2, T3 tools
U1, U2 plane
u Counterbore depth
V Counterbore mouth chamfering
v1, v2, v3, v4 Chamfering blade
W counterbore
W1 plane
w Counterbore hole diameter
α clearance angle
γ Rake angle
θ Left base angle
λ1, λ2 Chamfer angle
O Origin
x x-axis
y y axis
z z-axis

Claims (1)

In a cutting tool for counterbore drilling and chamfering using a throw-away tip on the work material in which the pilot hole is drilled,
A trapezoid EFCG in which a square ABCD having a chip thickness r and having an inscribed circle diameter k has a lower right vertex as a lower right vertex C, a left base angle θ (0 ° <θ <90 °), and a right base angle 90 ° , Remove the trapezoid EFCG part of the top base m and height n from the square ABCD, rotate the square ABCD 90 ° clockwise, and the same trapezoid from each vertex D, A, B as well as at vertex C The rake face (51) is defined as the figure formed by removing the flank, and the flank face (52) is formed so as to be at the flank angle α from the entire periphery of the rake face (51), and a mounting hole ( 53)
Mounting seat formed at the bottom of the body ( 31a ) Bottom of ( 32a ) And a mounting seat formed on the top of the body ( 31b ) Bottom of ( 32b ) Attached to the
A cutting tool capable of simultaneously counterboring and chamfering at two locations.

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