JP3120034B2 - Milling cutter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a milling cutter used for cutting wood, wood-based materials, synthetic resin-based materials, soft metal materials, and similar materials. The present invention relates to a milling cutter whose cutting radius hardly changes even when the spare blade is re-ground and then re-mounted.

[0002]

2. Description of the Related Art Heretofore, as means for fixing a blade of this kind of milling machine to a main body, there are methods such as brazing, screwing, through a backrest, and the like. In brazing, the change in the cutting radius must be corrected by adjusting the movement of the machine shaft. Also,
When fixing the blade body with the backing, etc., it took time and effort to adjust the cutting radius. Therefore, a milling cutter whose cutting radius does not change even when the blade body is polished has been developed.
No. 13 is published.

As shown in FIG. 8 (showing a part of the assembly of a blade supporting disk and a finger cutter), the blade supporting circle having substantially the same thickness as one finger cutter 218 is disclosed in this publication. The blade fitting groove 213 and the spring fitting groove 214 which are oblique in the rotation direction are continuously cut from the peripheral edge 212 of the plate 211, and the finger cutter 218 projecting from the peripheral edge 212 is removed in the tool fitting groove 213 in the thickness direction. It fits freely and forms a sliding slope 217 of about 45 degrees between the outer circumferential side 215 and the inner circumferential side 216 of the rear side edge of the fitting groove 213 in the rotation direction, and the finger cutter 218 has the inside of the sliding slope 217. The finger cutter 218 is shaped so as to closely fit into the blade fitting groove 213 except for a portion protruding from the peripheral edge 212, and the front edge in the rotation direction is ground by sharpening. Squeeze surface 220 to be applied Slot 214
A spring 221 fitted on the lower surface of the cutter 218 is set on the lower edge of the cutter 218 to grind the rake face 220. The decrease in the amount of protrusion is absorbed by the sliding of the cutter 218 on the slide slope 217, and the grinding of the rake face 220 is performed. Instead, the tip of the cutter 218 is configured to protrude at substantially the same position. 9 (a) and 9 (b) show another configuration. The flank 232 of the blade body 229 is provided on the outer peripheral side of one side of the milling body 226 of the milling machine 225 shown in FIG. A guide rail 227 is formed in parallel with the blade 229.
A guide plate 228 on which is mounted is slidably mounted, and an elongated hole 230 is formed in the guide plate 228. In addition, the blade body 229 is
At an angle with an inclined surface 234 provided on the milling body 226. Grinding the rake face 233 reduces the amount of protrusion by the guide plate 22 along the guide rail 227.
8 is moved so that the cutting surface 233 of the blade body 229 abuts against the inclined surface 234 so that the cutting edge is positioned on the cutting circle D, and is fixed from the elongated hole 230 of the guide plate 228 via the set bolt 231. It is configured.

[0004]

However, in the former case, after the rake face 220 of the cutter 218 is polished and then the cutter 218 is fitted into the cutter fitting groove 213, Front edge 215 on the outer circumference of the rear edge in the rotation direction
The cutter 218 is positioned by the spring 221 fitted in the spring fitting groove 214 of the fitting groove 213 in a state where a gap Δt is formed between the cutter 218 and the trailing edge 218a of the cutter 218. Since the positioning reference of the cutter 218 is the front edge in the rotation direction of the blade fitting groove 213, there is a problem that the finger cutter 218 moves rearward in the rotation direction where a cutting force is applied during use, and the cutting diameter is reduced. Also, in the latter case, when a cutting force is applied to the blade body 229, it is set and fixed at the elongated hole 230, and therefore, there is a problem that the cutting diameter is reduced by moving backward in the illustrated rotation direction. The present invention has been made to solve the above-mentioned conventional problems, and can be firmly fixed to a milling body with a simple mechanism, and the cutting radius hardly changes even when the blade body is polished. It is intended to provide a formula milling machine.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned technical problem, the present invention is directed to a first invention in which a plurality of cutter grooves are provided on an outer peripheral portion of a milling body, and a back seat accommodated in the cutter grooves. And a means for fixing the blade back to the milling body by pressing the blade back in the rotational direction of the blade groove by the backing, and a cutting radius when the rake face of the blade is polished. Means for compensating for the change in the diameter of the milling cutter is constituted by an inclined surface facing the inner periphery of the blade groove and an inclined surface formed on a back seat that comes into contact with the inclined surface. A plurality of blade grooves are provided in the part, a back seat accommodated in the blade grooves, a blade body pressed and fixed rearward in the rotation direction of the blade grooves by the back seat, and means for fixing the back seat to the milling body. The cutting radius when the rake face of the blade is polished The first correcting means, which is composed of an inclined surface facing the inner periphery of the blade groove and an inclined surface formed on a back seat that comes into contact with the inclined surface, is formed on the front side in the rotation direction of the blade body. The second invention comprises a second correcting means composed of an inclined surface and an inclined surface formed on the back seat that comes into contact with the inclined surface. The third invention is a means for fixing the back seat to the milling body. Is a cam, it can be applied to a thin blade body, for example, a finger cutter. The fourth invention is a correction amount of a change in a cutting radius caused by a difference in a radial position of the blade body. Is further corrected by changing the outer diameter relief angle and the cutting edge angle of the blade body depending on the radial position, so that the difference can be effectively applied to the form cutter. Compared with a conventional milling machine having an adjusting mechanism, the blade body is directly fixed to the rear in the rotation direction where a force is applied when the milling machine is used, so that the fixing can be further strengthened. In addition, as shown in FIG. 2, when the initial cutting edge position is P, if the cutting edge rake face 27 is polished by the polishing amount a as shown in FIG.
And the displacement of the cutting radius is q. Here, the first and second
According to the configuration of the present invention, the trajectory indicating the cutting edge position retracted by the polishing is, for example, the cutting circle D at the initial cutting edge position P.
So that the back seat moves at an angle θ with respect to the direction perpendicular to the rotation direction rear surface of the blade groove so that the tangent L of
Thus, for example, the cutting edge Q of the blade body becomes a point U on the tangent line L, and the displacement of the cutting radius becomes u, so that an amount corresponding to the displacement of the cutting radius when the blade body is polished can be projected, and this displacement amount u Is equivalent to the machining tolerance of the milling machine itself and has little effect on use. In addition, as illustrated in FIG. 3, the initial cutting is performed by setting an angle θ so that the locus L ″ is such that the cutting edge position P ″ at the time of final use is located on the cutting circle D at the initial cutting edge position P. The radius and the cutting radius at the time of final use can be made the same. Can be adjusted so that the maximum and minimum values of the cutting radius between initial and final use fall within a convenient tolerance.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 to 3 show a first embodiment of the present invention. 11) is a cross-sectional view showing a partial side view in which a blade body 25 is assembled to the milling body 12 of FIG.
1 comprises a milling body 12, a blade body 25, a back seat 30, and a fixing member 40. The milling body 12 has a blade edge diameter of 160 mm, and is provided on the outer periphery of the milling body 12 at an interval of, for example, a central angle of 90 degrees.
And a blade groove 13 for accommodating the back seat 30 and the fixing member 40. As shown in the figure, the blade groove 13 has a blade body contact surface 14 (rear surface in the rotation direction) and a wall surface 15 which is a front surface in the rotation direction opposed to each other in parallel at a predetermined interval. The contact surface 14 is formed to be shorter than the wall surface 15, and at the lower end thereof is formed an engagement projection 16 which projects into the blade groove 13 by a predetermined length and engages with the backrest 30.

As shown in the figure, the engaging projection 16 has a predetermined angle θ [tan θ = tan (β + γ) with respect to a line C1 perpendicular to the upper surface 17 perpendicular to the blade contact surface 14 and the blade contact surface 14. )
−tan γ], an engagement inclined surface 18 inclined downward to the bottom surface 20 side, and an inclined surface 19 having a predetermined angle is formed at a base of the engagement convex portion 16, and the inclined surface 19 and the wall surface 15 are formed. Between the horizontal portion 21 and the inclined portion 22 and an inclined surface 24 formed between the horizontal portion 21 and the inclined portion 22.
0 is formed and the blade groove 13 is formed in a substantially U-shape.
A swallowing recess 23 into which the backrest protrusion 34 of the backrest 30 is inserted is formed between the inclined portion 22 and the engagement protrusion 16. The blade body 25, the back seat 30, and the fixing member 40 are integrally assembled and fixed to the blade groove 13 thus formed.

The blade body 25 has a substantially trapezoidal cross section and has an upper and lower blade edge, and can be used for cutting twice. The blade body 25 has a blade contact surface of the blade groove 13. A vertical blade body rear surface 26 abutting on the blade 14 and a rake face 27 are formed on the opposite side of the blade body rear surface 26. A recess 28 is provided. As shown in FIG. 2, the upper and lower cutting edges of the blade body 25 are formed to have, for example, a cutting edge angle α (= 50 °), a cutting edge clearance angle β (= 20 °), and a rake angle γ (= 20 °). ing. At this time, the angle θ of the engagement inclined surface 18 of the engagement protrusion 16 is θ = 25 ° 24 ′ from the above equation. FIG. 2
In the figure, O is the rotation center of the milling cutter 11, P is the position of the cutting edge before polishing, D is a circle (grinding circle) centered at the point O passing through the point P, and L is a straight line perpendicular to the line OP passing through the point P ( Tangent)
And 27 is a rake face.

The back seat 30 is formed with a back seat rear surface 31 that contacts the rake face 27 of the illustrated blade body 25 and a back seat front surface 32 that inclines forward at a predetermined angle. It is formed in a vertical shape with a length, and a step surface 33 is formed in a lower part below the step surface 33.
3 is a back seat sliding contact inclined surface 35 slidably engaged with the engaging inclined surface 18 of the engaging convex portion 16 formed below the blade body contact surface 14 of the third embodiment.
Is formed. Further, a stepped recess 36 is formed at a predetermined position on the back surface 31 of the backing seat at right angles to the surface 31, and a spring member 37 having a predetermined spring pressure is provided in the stepped recess 36 with a depth end pinned. 38, and the rake face 2 of the blade body 25 is provided on the opening side.
A wedge member 39 that fits in a wedge-like manner with the engagement concave portion 28 that is concavely formed in the boss 7 is elastically attached.

The fixed member 40 has a fixed rearward surface 41 that is slidably contacted with the backside front surface 32 of the backing plate 30 and a fixed front surface that is slidably contacted with the wall surface 15 of the blade groove 13. A screw hole 43 is formed at a predetermined position between the two surfaces 41 and 42 so as to penetrate vertically.
, An adjusting screw 44 is screwed. The upper portion of the screw hole 43 is not threaded, so that even if the adjusting screw 44 is turned too much, the adjusting screw 44 is prevented from jumping out of the screw hole 43. The head of the adjusting screw 44 has a minus groove for engaging with the driver, and the driver can be inserted from above into the screw hole 43 penetrating vertically.

The fixing member 40 provided in this manner is mounted on the horizontal portion 21 of the bottom surface 20 of the blade groove 13 with the adjusting screw 44 being screwed upward and its tip being immersed in the screw hole 43. The fixed front surface 42 contacts the wall surface 15. Then, a wedge member 39 is brought into contact with the engaging recess 28 of the blade body 25 in a state where the back seat convex portion 34 of the back seat 30 is inserted into the swallowing concave portion 23 on the lower surface side of the engaging convex portion 16 of the blade groove 13, The blade body back surface 26 of the blade body 25 comes into contact with the blade body contact surface 14 of the blade groove 13, and the engagement inclined surface 18 of the engagement projection 16 has a back seat sliding contact inclined surface 35 of the back seat projection 34. Abut In this state, the fixing member 40
When the adjusting screw 44 is screwed forward, the fixing member 40 is moved upward, and the fixed rear surface 41 is brought into contact with the back seat front surface 32,
The blade body 25 is pressed against the blade body contact surface 1 while the spring member 37 is pressed.
4 is integrally connected to the back seat 30 via a wedge member 39 so as to be slidably contacted with the back plate 4. Further, by further screwing the adjusting screw 44, the backing plate 30 is slidably moved along the engagement inclined surface 18, and the blade body back surface 26 is moved along the blade body contact surface 14 on the blade body 25 side. After being slid in the outer circumferential direction, the cutting edge of the blade body 25 is positioned on a predetermined tangent line L.

Here, the positional accuracy of the cutting edge of the blade body 25 with respect to the cutting circle D will be described. FIG. 2 shows a conceptual diagram. When the initial blade edge position of the blade body 25 is P, the blade body 2
When the rake face 27 of No. 5 is polished by the polishing amount a, the cutting edge position is Q and the displacement amount with respect to the cutting circle D is q if the polishing amount is not corrected. Here, in the milling cutter 11 of the present embodiment, the cutting edge retreated by polishing the blade body 25 is the cutting edge position Q.
Is the cutting circle D at the initial cutting edge position P.
The back seat 30 is engaged with the blade body contacting surface 14 of the blade groove 13 so as to be located on the tangent L of the blade groove 13 at the lower portion of the blade body abutting surface 14 of the blade groove 13. Since the portion 16 is provided so as to move along the engagement inclined surface 18 at the angle θ, the cutting edge position of the blade body 25 becomes the position U on the tangent line L, and the displacement amount relative to the cutting circle D becomes u. tan θ = tan (β
+ Γ) -tanγ, the cutting edge position after cutting is located on the tangent line L.

The above-mentioned milling cutter 11 has a blade diameter of 160 m.
m, cutting edge angle α = 50 °, cutting edge clearance angle β = 20 °, rake angle γ = 20 °, total polishing amount after repeated polishing a = 2
mm, u = 0.028 mm for q = -0.855 mm (a =
If it is 1 mm, q = -0.437 mm and u = 0.007 mm). this
The accuracy of 0.028 mm is equivalent to the machining tolerance of the milling machine 11 itself and has almost no effect on use.

In the above description, the backrest 30 is perpendicular to the rotational direction rear surface 14 of the blade groove 13 so that the trajectory L of the cutting edge position moved by polishing is tangent to the cutting circle D at the initial cutting edge position P. Move along the engagement inclined surface 18 at the angle θ, but as shown in FIG. 3, the final use is performed on the cutting circle D at the initial cutting edge position P (when the re-grinding cannot be performed any more substantially). The angle θ may be set so that the locus L ″ is located such that the cutting edge position P ″ of FIG. For this purpose, tan θ = tan (β + γ) -tan (γ +
こ こ) (where ψ is the angle between the tangent L of the cutting circle D at the cutting edge position P and the trajectory L ″, and here, it is の of the central angle between the cutting edge position P and the cutting edge position P ″). .). By setting θ to satisfy this relationship, the initial cutting radius and the cutting radius at the time of final use can be made the same. In this case, the maximum displacement amount is u '= d / 2- (d / 2) × cosψ when 1/2 of the total polishing amount a until the final use is polished (ψ = 46 ′, θ = 24). In the above example, it is +0.006 mm. By adjusting the angle θ,
The maximum and minimum values of the cutting radius between initial and final use may be acceptable. In the above embodiment, the blade body 25 is provided on the back surface 3 of the back plate 30 of the back plate 30.
Although the abutment 1 and the wedge member 39 are integrally connected via the wedge member 39, the wedge member 39 may be replaced with a screw, a pin, or a concave / convex portion.

FIG. 4 shows a second embodiment of the present invention. The milling machine 51 includes a milling body 52 and a blade body 61.
And a backing member 65 and a fixing member 73.
The milling body 52 has a blade edge diameter of 160 mm in the same manner as described above, and on the outer peripheral side of the milling body 52, a blade 6
1, backrest 65 and blade groove 53 for accommodating fixing member 73
Are formed. As shown in the figure, the blade groove 53 has a blade body contact surface (rear surface in the rotation direction) 54 and a wall surface 55, which is a front surface in the rotation direction, opposed to each other in parallel at a predetermined interval. The contact surface 54 is formed to be shorter than the wall surface 55, and a relief concave portion 56 of the blade body 61 is formed at a lower end portion thereof. A recess 57 is formed, and the escape recess 56 and the swallow recess 5 are formed.
7, an engaging projection 58 is formed.
A line C2 perpendicular to the blade contact surface 54 is provided on the swallowing recess 57 side.
, An engagement inclined surface 59 is formed at a predetermined angle θa.

The blade body 61 is formed in a substantially parallelogram cross section and has a cutting edge at the top and bottom, and can be used for cutting twice. An angled surface 62a is formed. Rake face 6 before and after this
A concave portion 63 for preventing protrusion is formed at a predetermined position of No. 2. Further, like the blade body 25, the blade edge shape is formed to have a blade angle α (= 50 °), a blade clearance angle β (= 20 °), and a rake angle γ (= 20 °).

Further, as shown in the drawing, the back seat 65 is opposed to the blade body contact surface 54, and the back seat rear surface 66 which comes into contact with the rake face 62 of the blade body 61. A back surface 66 is formed in a vertical shape with a predetermined length, and a lower end thereof has a line C2 perpendicular to the blade contact surface 54.
A blade body receiving inclined surface 68 which is inclined downward toward the blade body contact surface 54 at a predetermined angle θb. The angle formed by the parallelogram of the blade body 61 is also set to θb, and the shaved surface 62a and the inclined surface 68 are in planar contact with each other. Further, a step surface 69 is formed at an end of the blade receiving slope 68, and a lower portion of the step surface 69 is inserted into the swallowing recess 57 so as to engage with the engaging protrusion 5.
A back seat convex portion 70 having a back seat sliding contact inclined surface 71 that slidably engages with the engagement inclined surface 59 of No. 8 is formed. Also,
At a predetermined position on the rear surface 66 of the back seat, a convex portion 72 is formed which is loosely fitted and engages with a protrusion 63 formed on the blade body 61 for preventing protrusion. The fixing member 73 is the same as that shown in FIG.
Since the configuration is the same as that of the fixing member 40, the same reference numerals are given and the description is omitted. The angles .theta.a = 20.degree. And .theta.b = 40.degree. With respect to the line C2 perpendicular to the blade contact surface 54. The relationship between the angle θa and the angle θb is set as follows: tanθb−tanθa = tan (β + γ) −tanγ.

The fixing member 73 provided in this manner is placed on the bottom surface 60 of the blade groove 53 with the adjusting screw 44 being screwed upward and the tip being immersed in the screw hole 43, and the fixed front surface 42 thereof. Is brought into contact with the wall surface 55. Then, the back-seat protrusion 70 of the back-seat 65 is inserted into the swallowing recess 57, and the protrusion 72 of the back-seat rear surface 66 and one of the protruding recesses 63 of the blade body 61 are prevented.
The blade body flank on the lower side of the figure is placed in contact with the blade body receiving inclined surface 68. The other rake face 62 of the blade body 61 abuts against the blade body abutment surface 54, and the back slope sliding contact slope 71 of the back seat protrusion 70 contacts the engagement slope 59 of the engagement protrusion 58. Touch In this state, the fixing member 73
When the adjusting screw 44 is advanced, the fixing member 73 is moved upward, and the fixed rear surface 41 is brought into contact with the back seat front surface 67,
The blade body 61 is slidably contacted with the blade body contact surface 54. Further, by further advancing the adjusting screw 44, the back seat 65 is slidably moved along the engagement inclined surface 59, and the blade body 61 is moved along the blade body receiving inclined surface 68, and the blade body is moved. The blade body 61 is slidably moved in the outer circumferential direction along the contact surface 54,
Is located on a predetermined tangent line L. In this embodiment, the first correcting means is constituted by the inclined surface 59 facing the inner periphery of the blade groove and the inclined surface 71 formed on the backing, and the inclined surface formed on the front side in the rotation direction of the blade body (see FIG. Side flank 62a)
The second correcting means is constituted by the inclined surface 68 formed on the backing that comes into contact with the inclined surface 68.

Since the milling cutter 51 of the present embodiment is constructed as described above, if the rake face is polished 2 mm in total by several times of polishing, the cutting radius is reduced by 0.855 mm in the prior art in which the amount of polishing is not corrected. Fixing member 7
By screwing the third adjustment screw 44, the back seat 65 is slidably moved along the engagement inclined surface 59, and the blade body 61 is moved along the blade body receiving inclined surface 68, and the blade body is moved. Contact surface 5
4, the edge is slid in the outer peripheral direction, so that even if it is polished, the edge radius is increased only by 0.028 mm and is kept substantially constant.

FIGS. 5 and 6 show a third embodiment of the present invention. The milling cutter 75 has a cutting edge diameter of 160 mm and is formed at a center angle of the milling body 76 at 90 ° intervals. As shown, the blade groove 77 has a vertical blade body contact surface 78 (rear surface in the rotation direction) and a bottom surface 79 formed at a right angle on the lower end side of the blade body contact surface 78. A backing seat 95 is provided on the front side in the rotation direction opposite to the blade body contact surface 78.
Is slidably fitted therein, and a disc cam 8 as a fixing member is provided at the back side of the back seat sliding recess 80.
5 is formed so as to be rotatable. An eave-shaped convex portion 82 is formed on the outer peripheral side of the sliding concave portion 80, and a blade body contact surface 78 is formed on a lower surface side of the eave-shaped convex portion 82.
A predetermined angle θ1 (= 22 ° 30
The inclined surface 83 of (1) is formed, and an inclined surface 84 is formed on the lower side corresponding to the inclined surface 83 in parallel with the inclined surface 83. The upper and lower inclined surfaces 83 thus formed,
A split hole 81 is formed continuously with the hole 84. The inclined surface 83 is an inclined surface facing the inner periphery of the blade groove 77.

As shown in FIG. 6, the blade 86 has a cutting edge X.
In addition, the side surface also has a cutting edge surface 87, the cutting edge diameter at the cutting edge X is 160 mm, the cutting edge angle α2 = 52 ° 06 ′, the cutting edge clearance angle β2 = 17 ° 54 ′, and the rake angle γ2 = 20 °. To form a common blade back surface 90 which is in contact with the blade rake surface 88, the flank 89 and the blade body contact surface 78, respectively, and the blade at the lower cutting edge Y of the cutting blade surface 87. 14 in diameter
0mm, cutting edge angle α1 = 50 °, cutting edge clearance angle β1 = 17 °,
The rake angle γ1 is set to 23 °, and an engagement concave portion 91 is formed on each of the blade rake faces 88 so as to be fitted and engaged with the back seat 95.

An engagement projection 97 is formed at a predetermined height on the blade coupling surface 96, which is the rear surface in the rotation direction of the backrest 95, to engage with the engagement recess 91 of the blade 86. ing. In addition, inclined surfaces 98 and 99 are formed above and below the blade body coupling surface 96 so as to be slidable along upper and lower inclined surfaces 83 and 84 of the back seat sliding concave portion 80 of the blade groove 77, respectively. 98,9
A receiving surface 100 of the disc cam 85 is formed between the nine. The blade body 86 thus provided has an angle θ1 of the back seat sliding recess 80 of the blade groove 77 in a state where the engagement recess 91 and the engagement projection 97 of the back seat 95 are fitted and engaged. It is inserted along the inclined surfaces 83 and 84. The blade 86 and the backrest 95 are pressed and fixed by rotating the disk cam 85.

Here, the rake face is polished several times to a total of 2 mm.
When polished, it is assumed that the cutting edge X has a cutting edge angle α2 = 50 °,
The clearance angle β2 = 20 ° and the rake angle γ2 = 20 °
If the cutting edge angle α1 at the cutting edge Y is also set to 50 ° equal to α2, the cutting radius at the cutting edge X increases by 0.028 mm, but the cutting radius at the cutting edge Y increases by 0.144 mm (θ1
= 25 ゜ 24 '). Here, the edge angles α1, α2 and the clearance angles β1, β2 of the cutting edge X and the cutting edge Y are different from each other, and are set as described above.
mm and the edge Y can be reduced together with 0.034 mm.

That is, tan θ1 = tan (β1 + γ
1) -tanγ1 = tan (β2 + γ2) -tanγ2
Since the cutting radius is different between X and Y, unless the rake angle γ is 0 ° (the rake angle is generally not 0 °), γ1 ≠ γ2. In order to satisfy β1 ≠ β2.
Since α1 + β1 + γ1 = α2 + β2 + γ2 (= 90 °, which is defined by the angle), α1 is also α
Must not be equal to 2. That is, if α1 and α2 or β1 and β2 are different so as to satisfy the above relation,
In both X and Y having different cutting radii, the variation of the cutting radius due to polishing can be both reduced. In this case as well, as shown in FIG. 3, in addition to the movement locus of the cutting edge being on the tangent line L, it is also possible to select θ1 such that it is L ″ or in the vicinity of L ″. In addition, the configuration in which the blade body and the backrest are fixed by the disk cam is such that the width of the blade body which cannot be fixed by the fixing screw is small and the thickness of the milling body is thin, for example, a finger. Advantageously applied to cutters.

FIG. 7 shows a fourth embodiment of the present invention, in which a milling cutter 101 comprises a milling cutter 102 and a blade groove formed at a center angle of 90 degrees of the milling cutter 102.
Blade 115 and back seat 120 and fixing member 125 housed in 103
It is composed of This milling cutter 101 has a
The blade groove 103 formed in the milling body 102 has a vertical blade contact surface (rotational rear surface) 104, a bottom surface 105, a blade contact surface 104, The wall 106 is formed by a wall surface 106 that is a rotation front surface facing the space, and an eave-shaped convex portion 107 is formed on the outer peripheral side of the wall surface 106 so as to protrude inward of the blade groove 103.
On the lower surface of the eave-shaped convex portion 107, there is formed a back contact sliding inclined surface 108 having a predetermined angle θ (= 25 ° 24 ′) with respect to a line C4 perpendicular to the blade body contact surface 104. Further, at a predetermined position of the bottom surface 105 near the wall surface 106, a fitting recess of the spring member 132 is provided.
109 is recessed. At a predetermined position of the eave-shaped projection 107, a screw hole 110 penetrating toward the inside of the groove 103 is screwed and a screw 111 is screwed.

The blade body 115 has a substantially trapezoidal cross section and has upper and lower blade edges and can be used for cutting twice. The blade body 115 comes into contact with the blade body of the blade groove 103. A vertical blade body rear surface 116 in contact with the surface 104 and a rake face 117 are formed on the opposite side of the blade body rear surface 116, and a center portion of the rake surface 117 is provided with an engaging member for engaging and connecting with the back seat 120. A mating recess 118 is provided. The shape of the upper and lower cutting edges of the blade 115 is
For example, the cutting edge angle α (= 50 °), the cutting edge clearance angle β (= 20
°), and a rake angle γ (= 20 °).

The engaging recess of the blade body 115 is located at a predetermined height on the blade body coupling surface 121 which is the rear surface in the rotation direction of the back seat 120.
An engagement protrusion 122 is formed to engage with the engagement 118. An inclined surface 123 is formed on the upper surface of the blade body coupling surface 121 so as to be slidable in accordance with the angle of the inclined back surface 108 of the eave-shaped convex portion 107 of the blade groove 103. On the side, a back seat front surface 124 which is inclined forward at a predetermined angle to be in sliding contact with the fixing member 125 is formed.

The fixing member 125 is a fixed rear surface 126 which is slidably contacted with the rear surface 124 of the back seat 120 of the back seat 120 and a fixed front surface which is slidably contacted with the wall surface 106 of the blade groove 103.
An upper surface 128 and a lower surface 129 which are substantially parallel to the back-sliding inclined surface 108 of the eaves-like convex portion 107 and the eaves-like convex portion 107 are formed in a wedge shape having a substantially deformed rectangular cross section in the drawing, and
A receiving recess 130 of the spring member 132 is formed on the lower surface 129 so as to face the fitting recess 109 of the bottom surface 105.
Is recessed.

The fixing member 125 provided in this manner is supported by a spring member 132 having a predetermined spring pressure between the bottom surface 105 of the blade groove 103 and the eave-shaped convex portion 107 in the outer circumferential direction. 106 and slidably in contact with the receiving recess 13
At 0, the tip of the screw 111 faces. Also, the blade 115
The engaging protrusion 122 of the blade body coupling surface 121 of the back seat 120 is fitted and connected to the engaging concave portion 118 of the rake face 117, and the back seat 120 is fixed to the front surface 124 of the back seat 120 by the fixing member 125. The fixed rear surface 126 is slidably contacted with the upper inclined surface 12.
Numeral 3 is slidably contacted with a back contact sliding inclined surface 108 of the eave-shaped convex portion 107. Here, the fixing member 125 is
The backseat 120 is moved along the backsliding sliding inclined surface 108, and the blade body 115 is moved to the outer circumference side along the blades contact surface to be Is located on a predetermined tangent line L.

In this case, the tip of the screw 111 is not in contact with the fixing member 125 , and the fixing member 125 is
In the state of being urged by 2 , during cutting rotation, the fixing member 125 acts as a wedge between the wall surface 106 and the back seat 120 due to the centrifugal force, and acts to firmly fix the blade body 115. When the blade 115 is mounted or removed, the screw 111 is screwed in and the fixing member 125 is pressed down against the spring 132 so as to be mounted or removed.

Since the milling cutter 101 of this embodiment is constructed as described above, if the rake face is polished 2 mm in total by several times of polishing, the cutting radius is reduced by 0.855 mm in the prior art in which the amount of polishing is not corrected. With such a configuration, the backing seat 120 is the backing sliding contact inclined surface 10 of the eave-shaped convex portion 107.
8 and the blade body 115 is slid and moved along the blade body contact surface 104 in the outer peripheral direction. Therefore, even if it is polished, the cutting radius only increases by 0.028 mm and is almost constant. Is held. Further, the back seat 120 slides along the eaves-like convex portion 107 which extends rearward in the rotation direction on the outer peripheral side of the wall surface (front surface in the rotation direction) of the blade groove 103 and has the back surface sliding contact inclined surface 108. In this way, it is possible to prevent cutting chips from entering the blade groove 103.

In the above embodiments, the angles θ, θ 1, θa, θb are set so that the cutting edge is mainly located on the tangent of the cutting diameter at the initial cutting edge position, but the angles can be changed as appropriate.

[Brief description of the drawings]

FIG. 1 is a partial side view of a milling cutter according to a first embodiment of the present invention, in which a blade is attached to a blade groove.

FIG. 2 is a conceptual diagram of a blade tip displacement amount with respect to a cutting diameter when a rake face of a blade body is polished.

FIG. 3 is an explanatory diagram of correction of a blade edge displacement amount.

FIG. 4 is a partial side view of a milling cutter according to a second embodiment of the present invention, in which a blade is assembled to a blade groove.

FIG. 5 is a partial side view of a milling cutter according to a third embodiment of the present invention, in which a blade is attached to a blade groove.

FIG. 6 is a front view of the blade body of FIG. 5;

FIG. 7 is a partial side view of a milling cutter according to a fourth embodiment of the present invention, in which a blade is assembled to a blade groove.

FIG. 8 is a partial side view of a conventional finger cutter.

FIG. 9 (a) is a partial side view of another conventional milling machine. (b) It is sectional drawing of Fig.9 (a).

[Explanation of symbols]

 11, 51, 75, 101 Implantable milling cutter 12, 52, 76, 102 Milling body 13, 53, 77, 103 Blade groove 25, 61, 86, 115 Blade body 27, 62, 88, 117 Rake surface 30, 65 , 95, 120 Back seat 18, 59 Engaging inclined surface 35, 71, 108 Back seat sliding contact inclined surface 68 Blade body receiving inclined surface 83, 98, 123 Inclined surface 40, 73, 125 Fixing member 85 Disk cam θ, θ1, θa, θb Inclined surface angle β Cutting edge clearance angle γ Rake angle q, u Displacement

(56) References JP-A-6-285813 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23C 5/20-5/24 B27G 13/08

Claims (4)

(57) [Claims] 1. A plurality of blade grooves are provided in an outer peripheral portion of a milling body, a back seat accommodated in the blade grooves, a blade body pressed and fixed rearward in the rotation direction of the blade grooves by the back seat, and a back seat. Means for fixing the cutting surface to the milling body, and means for correcting a change in the cutting radius when the blade body rake face is polished, the inclined surface facing the inner periphery of the blade groove, and the inclined surface And a sloped surface formed on a backing that abuts against the blade. 2. A plurality of blade grooves are provided on an outer peripheral portion of a milling body, a back seat accommodated in the blade grooves, a blade body pressed and fixed rearward in the rotation direction of the blade grooves by the back seat, and a back seat. Means for fixing the cutting surface to the milling body, and means for correcting a change in the cutting radius when the blade body rake face is polished, the inclined surface facing the inner periphery of the blade groove, and the inclined surface And the inclined surface formed on the backing that comes into contact with
A cutting blade comprising: a correcting means; and a second correcting means including an inclined surface formed on the front side in the rotation direction of the blade body and an inclined surface formed on a back seat that comes into contact with the inclined surface. Formula milling. 3. The milling cutter according to claim 1, wherein the means for fixing the backing to the milling body is a cam. 4. The difference in the correction amount of the change in the cutting radius caused by the difference in the radial position of the blade body is further corrected by changing the outer diameter relief angle and the cutting edge angle of the blade body depending on the radial position. The milling cutter according to any one of claims 1 to 3, characterized in that: