JP2022046889A - Tool holder - Google Patents

Abstract

To provide a tool holder that can achieve high-precision cutting-off processing, while maintaining a state where the tool holder is surely attached to a turret face.SOLUTION: A tool holder 100 is constituted of a holder base part 110 that is contacted with and fixed to a turret face 12a of a turret 12 provided in a machine tool, and a blade holding part 120 that is integrally molded with the holder base part 110 and attachably and detachably holds a blade 200 for cutting-off processing. The blade holding part 120 protrudes in a cutting-off direction of the blade 200 for cutting-off processing from the holder base part 110. The holder base part 110 and the blade holding part 120 are formed to fit into the turret face 12a in a front view of the turret face 12a of the turret 12.SELECTED DRAWING: Figure 2

Description

The present invention relates to a tool holder for a cutting tool mounted on a machine tool turret.

Conventionally, the tool holder of a cutting tool mounted on the turret of a machine tool has various holder forms depending on the cutting function of the cutting tool, and the cutting tool held in this tool holder has a circumference with respect to the work. In the case of parting off such as grooving or cutting, for example, a cutting tool for parting off having a blade called a cutting insert for cutting through a work and a columnar holder for holding the blade is used (for example, a cutting tool for parting off is used. See Patent Document 1).

Japanese Unexamined Patent Publication No. 2002-33709

Therefore, as a tool holder for mounting such a cutting tool for parting off to the turret of a machine tool, as shown in FIG. 7, a plate-shaped holder base 511 fixed to the turret surface 12a of the turret 12 and this There is a tool holder 510 composed of a tool holding portion 512 for holding a holder 521 of a cutting tool 520 projecting in an L shape from one end of the holder base 511 toward the work W.

However, in the above-mentioned tool holder 510, when the cutting tool 520 for parting off is sent in the direction orthogonal to the tangent line of the round bar-shaped work W (in the direction of arrow D1 in FIG. 7), it is opposite to the parting direction D1. A force in the direction is applied to the cutting edge of the blade 522 as a reaction force F1.
This reaction force F1 is generated on the holder base 511 via the tool holding portion 512, and is bent from the turret surface 12a to the portion of the holder base 511 that protrudes like a cantilever (enclosed portion by the alternate long and short dash line in FIG. 7). Since the moment acts, the tool holder 510 is deformed.
Due to this deformation, there is a problem that the parting position of the cutting tool 520 held in the tool holder 510 with respect to the work W is displaced, and the machining accuracy of the parting process is lowered.

Therefore, the present invention solves the problems of the prior art as described above, that is, the object of the present invention is to maintain a reliable mounting state of the tool holder on the turret surface and perform high-precision parting off. Is to provide a tool holder that achieves.

First, the present invention comprises a holder base that abuts and is fixed to the turret surface of a turret provided in a machine tool, and a blade holding portion that is integrally molded with the holder base to detachably hold a parting blade. In the configured tool holder, the blade holding portion projects from the holder base toward the parting direction of the parting blade, and the holder base and the blade holding portion press the turret surface of the turret. It is characterized in that it is formed so as to fit within the turret surface when viewed from the front.

Secondly, the blade holding portion is characterized in that the blade for parting off is projected from the holder base so as to be positioned near the center of the holder base in a state where the turret surface of the turret is viewed from the front. ..

Thirdly, the blade holding portion cuts out a part of both side surfaces of the blade holding portion in a stepped shape to attach the parting blade to the left and right pair of blade attachment surfaces and the parting blade. It is characterized by having a pair of left and right blade seating surfaces for seating toward the holder base.

Fourth, the blade holding portion is formed so that the parting-off blade can be freely replaced with either one of both side surfaces of the blade holding portion.

Fifth, the blade holding portion is formed so that only the parting tip portion of the parting blade is projected from the blade holding portion in the parting direction.

In the present invention, even if a feed component force in the parting direction is generated in the holder base via the blade holding portion during parting off processing, the holder base is reliably received in the turret surface without protruding from the turret, as in the conventional case. Since the holder base is not deformed, the tool holder is securely attached to the turret surface, and as a result, the parting blade is not distorted or tilted in the parting direction, and the side surface of the blade is unevenly worn. Is reduced, and high-precision parting off can be achieved.

FIG. 3 is a perspective view showing a machine tool provided with a turret to which a tool holder according to an embodiment of the present invention is mounted. The perspective view of the tool holder which is the Example of this invention. An exploded view of the tool holder shown in FIG. FIG. 2 is a perspective view of a parting off blade attached to one side surface of the tool holder shown in FIG. FIG. 2 is a perspective view of a parting blade attached to the other side surface of the tool holder shown in FIG. Explanatory drawing of the force applied to the tool holder at the time of parting off seen from the direction of the rotation axis of a spindle. Explanatory drawing of the force applied to the tool holder at the time of parting off when viewed from the bottom to the top of the machine tool. Explanatory drawing of the tool holder of the prior art at the time of parting off when viewed from the bottom to the top of the machine tool.

The tool holder of the present invention is composed of a holder base that abuts and fixes the turret surface of the turret provided in the machine tool, and a blade holding portion that is integrally molded with the holder base and holds the parting blade detachably. The blade holding portion protrudes from the holder base toward the parting direction of the parting blade, and these holder bases and the blade holding portion fit within the turret surface with the turret surface of the turret viewed from the front. It is formed and reliably receives the reaction force received from the parting direction of the parting blade during parting off in the turret surface, and maintains the reliable mounting state of the tool holder on the turret surface without deforming the holder base. Any specific embodiment may be used as long as it achieves high-precision parting off.

That is, in a specific embodiment of the tool holder of the present invention, the holder base and the blade holding portion are formed so as to fit in the turret surface with the turret surface of the turret viewed from the front, that is, the turret of the turret. It suffices if it is formed so as not to protrude from the surface. For example, a T-shaped protrusion may be made from the vicinity of the center of the holder base toward the work, or an L-shape may be formed from one end of the holder base toward the work. It may protrude to.
In particular, when the blade holding portion is formed so as to project in a T shape from the vicinity of the center of the holder base toward the work, the parting blade can be used with one tool holder on the front spindle side and the back spindle of the tool holder. It is more preferable because it can be freely attached to either side of the side.

On the other hand, regarding the specific blade form of the parting blade mounted on the tool holder of the present invention, parting processing such as circumferential grooving, grooving, and cutting is performed on the work held on the spindle. If possible, any blade form may be used, and for example, it is composed of a blade made of a super hard alloy, which is also called a cutting insert or a cutting tip that cuts through a workpiece, and an adapter portion for a flat plate-shaped blade that holds the blade. It is more preferable that it is.
It is desirable that the blade constituting the parting-off blade and the blade adapter portion holding the blade have an flat plate shape as a whole, but both may be integrally and inseparably assembled. It does not matter if the blade is assembled so that it can be exchanged according to the material of the work.
The blade for parting off described above may be a commercially available blade that is usually used, but it can also be manufactured independently according to the blade holding portion of the tool holder.

Hereinafter, the tool holder 100, which is an embodiment of the present invention, will be described with reference to FIGS. 1 to 4.
FIG. 1 is a perspective view showing a machine tool 10 provided with a turret 12 to which the tool holder 100 according to the embodiment of the present invention is mounted, and FIG. 2 is a perspective view of the tool holder 100 according to the embodiment of the present invention. It is a figure, and FIG. 3 is an assembly exploded view of the tool holder 100 shown in FIG. FIG. 4A is a perspective view of the parting blade 200 attached to one side surface of the tool holder 100 shown in FIG. 2, and FIG. 4B is a parting process attached to the other side surface of the tool holder 100. It is a perspective view of a blade 200.
Note that FIG. 1 shows the three-axis directions of the XYZ of the machine tool 10. Further, in FIGS. 2 to 4, in order to show the configurations of the tool holder and the parting blade on the three axes orthogonal to each other, the three axis directions of xyz orthogonal to each other are shown.

<1. Outline of machine tools ＞
First, with reference to FIG. 1, a machine tool 10 provided with a turret 12 to which a tool holder 100, which is an embodiment of the present invention, is mounted will be described.
The machine tool 10 is a so-called turret lathe, and is provided with a spindle 11 that grips and rotates a round bar-shaped work W, and a turret 12 that is arranged in the vicinity of the spindle 11 and on which a tool holder 100 is mounted. ..
In the machine tool 10 using the tool holder 100 of this embodiment, two spindles, a front spindle 11 and a back spindle (not shown) facing the front spindle 11, are provided, but only the front spindle 11 is provided. It doesn't matter if you have it.
Further, the turret 12 provided by the machine tool 10 is provided with 12 flat turret surfaces 12a whose outer peripheral surface is divided into 12 equal parts, and one of these turret surfaces 12a is the tool of the present embodiment. The holder 100 is attached.
The turret 12 is not limited to a turret 12 having an outer peripheral surface divided into 12 equal parts, that is, a dodecagonal turret, and may be a polygon. For example, the turret 12 may be octagonal.

<2. Tool holder structure>
The structure of the tool holder 100, which is an embodiment of the present invention, will be described in detail below.
First, as shown in FIGS. 2 and 3, the tool holder 100 has a holder base 110 that abuts and is fixed to the turret surface 12a of the turret 12 provided on the machine tool 10, and the holder base 110 is integrally formed and projected. It is composed of a blade holding portion 120 that detachably holds the cutting blade 200 and the dummy plate 300.
In this embodiment, the tool holder 100 has a substantially T shape including a holder base 110 and a blade holding portion 120.

The holder base 110 and the blade holding portion 120 are formed so as to fit within the turret surface 12a with the turret surface 12a of the turret 12 viewed from the front.
More specifically, the holder base 110 is provided in the turret surface 12a without protruding from the turret surface 12a, and the blade holding portion 120 fits in the turret surface 12a with the turret surface 12a viewed from the front. Is formed in.

The holder base 110 is formed with a turret contact surface 111 and a bolt hole 112 that come into contact with the turret surface 12a.
The turret contact surface 111 has a rectangular shape that matches the shape of the turret surface 12a, and has dimensions that abut on substantially the entire surface of the turret surface 12a.
The bolt holes 112 are formed through the four corners of the holder base 110 in the thickness direction. The holder base 110 is fixed to the turret surface 12a by bolts that have passed through these bolt holes 112.

The blade holding portion 120 projects from the holder base 110 in the x-axis direction.
The blade holding portion 120 is provided on the holder base 110 so as to position the parting off blade 200 near the center of the holder base 110.

Then, as shown in FIG. 3, the blade holding portion 120 partially cuts out both side surfaces of the blade holding portion 120 in a stepped shape, and a pair of left and right blade attachment surfaces 121 to which the parting off blade 200 is attached. And a pair of left and right blade seating surfaces 122 for seating the parting off blade 200 toward the holder base 110.

The blade attachment surface 121 is formed on both side surfaces of the blade holding portion 120.
Therefore, the parting off blade 200 used for machining on the front spindle side or the parting off blade 200 used for machining on the back spindle side can be freely replaced with either one of the both side surfaces of the blade holding portion 120. ing.
The height H1 of the blade attachment surface 121 in the y-axis direction is substantially equal to the height H2 of the parting off blade 200 in the y-axis direction.
That is, the parting-off blade 200 is brought into contact with the blade attachment surface 121 in the y-axis direction in substantially the entire width.

Such a blade holding portion 120 is formed so that only the parting tip portion 211, which will be described later, of the parting blade 200 is projected from the blade holding portion 120 in the x-axis direction.
More specifically, in a state where the parting off blade 200 is held by the blade holding portion 120, only the parting tip portion 211 of the parting off blade 200 is used for the main component force direction blade described later in the x-axis direction. The blade holding portion 120 is provided so as to protrude from the seat surface 122b.

The blade seating surface 122 has a feed direction blade seating surface 122a on which the end face of the parting off blade 200 in the x-axis direction is seated, and a main component force direction in which the end face of the parting off blade 200 in the y-axis direction is seated. It is provided with a seat surface 122b for blades.

The width W1 of the seating surface 122a for the feed direction blade is set to be approximately the same as the thickness T1 of the parting-off processing blade 200 to be seated.
The width W2 of the seat surface 122b for the main component force direction blade is set to be approximately the same as the thickness T2 of the parting-off processing blade 200 to be seated.

<3. Structure of parting blade>
Next, the structure of the parting off blade 200 attached to the tool holder 100, which is an embodiment of the present invention, will be described in detail below.
The parting off blade 200 is a parting blade 200 shown in FIG. 4A and a parting off blade 200 shown in FIG. 4B, which are replaced with each of the pair of blade attachment surfaces 121 formed on both side surfaces of the blade holding portion 120. It is divided into blade 200 and.
In this embodiment, the parting off blade 200 shown in FIG. 4A is attached to one side surface of the tool holder 100. Here, when the parting blade 200 shown in FIG. 4B is used, the parting blade 200 shown in FIG. 4B is fixed to the side surface of the blade holding portion 120 to which the dummy plate 300 is fixed in FIG.

Such a parting blade 200 is composed of a blade portion 210 that functions as a blade and a blade adapter portion 220 that is held by the blade holding portion 120 of the tool holder 100, and has a flat plate shape.

The blade portion 210 is integrally formed with the blade adapter portion 220 and is formed thinner than the blade adapter portion 220.
The blade portion 210 is set so that the distance from the cutting edge to the portion connected to the blade adapter portion 220 in a substantially arc shape is set to be about the same as the radius of the work W before machining.
The blade portion 210 has a parting tip portion 211 that can detachably hold the cutting insert 211a at the cutting edge.

The cutting insert 211a is made of a material having extremely high strength with respect to the work W, for example, a cemented carbide.

The blade adapter portion 220 has a holder contact surface 221 that abuts on the blade attachment surface 121 of the blade holding portion 120 described above, and a blade holding portion 120 from a surface opposite to the holder contact surface 221. A fastening member insertion hole 222 through which a fastening member T such as a screw can be passed is formed toward the blade attachment surface 121.
As a result, the parting-off blade 200 is fixed to the blade holding portion 120 in a state where the holder contact surface 221 is brought into contact with the blade attachment surface 121 of the blade holding portion 120 by being screwed.

When the parting off blade 200 is fixed to the blade holding portion 120 in a state where the holder contact surface 221 is in contact with the blade attachment surface 121 of the blade holding portion 120, the x-axis of the parting off blade 200 The end face of the parting blade 200 in the direction faces the seating surface 122a for the feed direction blade of the blade holding portion 120, and the end face of the parting blade 200 in the y-axis direction is the main component force direction blade of the blade holding portion 120. Facing the seat surface 122b.

<4. Dummy plate structure>
The dummy plate 300 is fixed to one of the pair of blade attachment surfaces 121 formed on both side surfaces of the blade holding portion 120.
The dummy plate 300 prevents chips from entering the screw holes of the blade attachment surface 121 on the side where the parting blade 200 is not fixed, and prevents the chips from damaging the blade attachment surface 121. A fastening member T is passed through a bolt hole or a screw hole used for fixing the cutting blade 200 and fixed to the blade attachment surface 121 (see FIG. 3).
The dummy plate 300 is adjusted to a size that fits inside the blade attachment surface 121 in the x-axis direction and the y-axis direction while being fixed to the blade attachment surface 121 of the blade holding portion 120. The parting blade 200 fixed to one side surface of the blade 200 does not interfere with the parting process.

<5. Force applied to the tool holder of this embodiment>
Next, with reference to FIGS. 5 and 6, the force applied to the tool holder 100 by parting off will be described.
FIG. 5 is an explanatory diagram of the force applied to the tool holder 100 during parting off when viewed from the direction of the rotation axis of the spindle, and FIG. 6 is a diagram showing the tool during parting off when viewed from below to above the machine tool. It is explanatory drawing of the force applied to the holder 100.
Note that FIGS. 5 and 6 show the three-axis directions of the XYZ of the machine tool 10.

Here, in the tool holder 100 fixed to the turret 12, the x-axis shown in FIGS. 2 to 4 corresponds to the X-axis of the machine tool 10 and the y-axis corresponds to the machine tool 10 due to the rotation of the turret 12 during parting off. The z-axis corresponds to the Y-axis of the machine 10 and is positioned at the position corresponding to the Z-axis of the machine tool 10.
As a result, the x-axis corresponds to the parting direction D1 (hereinafter referred to as “machining feed direction”) of the parting blade 200, and the y-axis is the direction of the main component force loaded on the parting blade 200. Corresponding to D2, the z-axis corresponds to the direction of the spindle 11 of the machine tool 10.

When the parting machine 10 starts parting off and the parting blade 200 is fed in the machining feed direction D1 which is the direction in which the parting blade 200 is pressed against the work W in the direction orthogonal to the tangent line of the work W, the machining feed direction D1 is defined as the machining feed direction D1. The feed component force F1 in the reverse direction and the main component force F2 in the tangential direction of the work W are loaded on the parting tip portion 211 of the parting blade 200.

Due to the feed component force F1 loaded on the parting tip portion 211 of the parting off blade 200, the end surface of the machining feed direction D1 of the parting off blade 200 comes into contact with the bearing surface 122a for the feed direction blade, so that the feed amount The force F1 is received by the seating surface 122a for the feeding direction blade, and is loaded on the turret surface 12a via the blade holding portion 120 and the holder base portion 110.
Since the width W1 of the seat surface 122a for the feed direction blade is set to be about the same as the thickness T1 of the parting-off processing blade 200 to be seated, the feed component force F1 is reliably received.

The feed component force F1 received by the bearing surface 122a for the feed direction blade in this way is a holder base formed so as to be contained in the turret surface 12a (between the two two-dot chain lines shown in FIG. 6). Occurs at 110.
As shown in FIG. 6, the tool holder 100 forms a substantially T shape composed of the holder base 110 and the blade holding portion 120, so that the feed component force F1 generated in the holder base 110 is unevenly distributed in the holder base 110. A well-balanced distributed load is applied in the left-right direction from the central portion of the holder base 110 without being loaded.

On the other hand, as shown in FIG. 5, the main component force F2 applied to the parting tip portion 211 of the parting off blade 200 is the main component force at the end face in the direction D2 of the main component force of the parting off blade 200. Since it abuts on the bearing surface 122b for the directional blade, the main component force F2 is received by the bearing surface 122b for the main component directional blade.
Since the width W2 of the seat surface 122b for the main component force direction blade is set to be approximately the same as the thickness T2 of the parting-off processing blade 200 to be seated, the main component force F2 is reliably received.
Further, the blade holding portion 120 holds the parting blade 200 so that only the parting tip portion 211 of the parting blade 200 protrudes from the seat surface 122b for the blade in the main component direction in the X-axis direction. As a result, the bending in the blade thickness direction, which tends to occur in the parting blade 200, is suppressed by the main component force F2 generated during the parting process.
Further, by making the height H1 of the blade attachment surface 121 in the Y-axis direction substantially equal to the height H2 of the parting-off blade 200 in the Y-axis direction, the parting-off blade 200 is bladed in the Y-axis direction. Since the attachment surface 121 abuts at a substantially width, the main component force F2 generated during the parting process further suppresses the deflection in the blade thickness direction that tends to occur in the parting blade 200.

<6. Effect of the tool holder of this embodiment>
According to the tool holder 100 of the present embodiment described above, the blade holding portion 120 protrudes from the holder base 110 in the parting direction (X-axis direction) of the parting blade 200, and the holder base 110 and the blade holding portion The 120 is formed so as to fit in the turret surface 12a with the turret surface 12a of the turret 12 viewed from the front.
Even if the feed component force F1 is generated in the holder base 110 via the blade holding portion 120 during parting off processing, the holder base 110 is reliably received in the turret surface 12a without protruding from the turret 12, and the holder base is as in the conventional case. Because it does not deform 110
The tool holder 100 is securely attached to the turret surface 12a, and as a result, the parting blade 200 is not distorted or tilted in the parting direction, and uneven wear on the side surface of the blade is reduced, resulting in high accuracy. Parting off can be achieved.

Further, according to the tool holder 100 of the present embodiment, the blade holding portion 120 positions the parting blade 200 near the center of the holder base 110 with the turret surface 12a of the turret 12 viewed from the front. Since the feed component force generated from the parting off blade 200 during parting off process acts in the left-right direction from the central portion of the holder base 110 due to the protrusion from 110, this feed component force F1 is used by the blade holding portion 120. It can be distributed to the turret 12 in a well-balanced manner in the left-right direction from the central portion of the holder base 110 via the above.

Further, according to the tool holder 100 which is an embodiment of the present invention, the blade holding portion 120 cuts out a part of both side surfaces of the blade holding portion 120 in a stepped shape, and a pair of left and right blades to which the parting blade 200 is attached is attached. By having a blade attachment surface 121 and a pair of left and right blade seat surfaces 122 for seating the parting off blade 200 toward the holder base 110, the blade seat surface 122 of the blade holding portion 120 is provided. However, the feed component force F1 is reliably received, and the feed component force F1 is loaded on the turret surface 12a via the blade holding portion 120 and the holder base portion 110. Deformation of the base 110 can be reliably suppressed.

Further, according to the tool holder 100 which is an embodiment of the present invention, the blade holding portion 120 is formed so that the parting off blade 200 can be freely replaced with one of the misalignments on both side surfaces of the blade holding portion 120. As a result, even the parting blade 200 used for machining on the front spindle side or the parting blade 200 used for machining on the back spindle side can be replaced with one tool holder 100, as in the conventional case. Since it is not necessary to prepare the tool holder 100 corresponding to each of the parting blades 200, the number of points possessed by the tool holder 100 can be halved.

Further, according to the tool holder 100 which is an embodiment of the present invention, the blade holding portion 120 projects only the parting tip portion 211 of the parting off blade 200 from the blade holding portion 120 toward the machining feed direction D1. As a result, the blade holding portion 120 suppresses the deflection in the blade thickness direction that tends to occur in the parting blade 200 due to the main component force F2 generated during the parting process. It is possible to improve the machining efficiency by increasing the machining feed rate during cutting.

In the tool holder 100 which is an embodiment of the present invention, the tool holder 100 which feeds the parting blade 200 only in the parting direction (X-axis direction) is exemplified, but in addition to the parting direction, the axial direction of the spindle (Z) The parting blade 200 may be fed in the axial direction). Further, when the parting blade 200 is fed in the Z-axis direction, it goes without saying that the blade attachment surface 121 of the blade holding portion 120 functions as a surface that receives the feed component force generated in the axial direction of the main shaft.

10 ・ ・ ・ Machine tool 11 ・ ・ ・ Spindle 12 ・ ・ ・ Turret 12a ・ ・ ・ Turret surface 100 ・ ・ ・ Tool holder 110 ・ ・ ・ Holder base 111 ・ ・ ・ Turret contact surface 112 ・ ・ ・ Bolt hole 120・ ・ ・ Blade holding part 121 ・ ・ ・ Blade attachment surface 122 ・ ・ ・ Blade seat surface 122a ・ ・ ・ Feed direction blade seat surface 122b ・ ・ ・ Main component direction blade seat surface 200 ・ ・ ・ Parting off Machining blade 210 ・ ・ ・ Blade part 211 ・ ・ ・ Parting tip part 211a ・ ・ ・ Cutting insert 220 ・ ・ ・ Blade adapter part 221 ・ ・ ・ Holder contact surface 222 ・ ・ ・ Fastening member insertion hole 300 ・・ ・ Dummy plate W ・ ・ ・ Work D1 ・ ・ ・ Parting off direction (machining feed direction)
D2 ・ ・ ・ Main component direction F1 ・ ・ ・ Feed component force F2 ・ ・ ・ Main component force T ・ ・ ・ Fastening member

Claims (5)

A tool holder composed of a holder base that abuts and is fixed to the turret surface of a turret provided in a machine tool, and a blade holding portion that is integrally molded with the holder base and holds a parting blade detachably. ,
The blade holding portion protrudes from the holder base toward the parting direction of the parting blade.
A tool holder in which the holder base and the blade holding portion are formed so as to fit within the turret surface with the turret surface of the turret viewed from the front. The tool holder according to claim 1, wherein the blade holding portion protrudes from the holder base so as to position the parting-off blade near the center of the holder base with the turret surface of the turret viewed from the front. .. The blade holding portion cuts out a part of both side surfaces of the blade holding portion in a stepped shape to attach the parting blade to the left and right pair of blade attachment surfaces and the parting blade to the holder base. The tool holder according to claim 1 or 2, which has a pair of left and right blade seating surfaces to be seated toward. The invention according to any one of claims 1 to 3, wherein the blade holding portion is formed so that the parting-off blade can be freely attached to either one of both side surfaces of the blade holding portion. Tool holder. Any one of claims 1 to 4, wherein the blade holding portion is formed so that only the parting tip portion of the parting blade is projected from the blade holding portion in the parting direction. The tool holder described in 1.

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