JP2002355701A - Cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting tool capable of preventing breaking of a wire of a sensor circuit due to chips and detecting tool longevity in high precision. SOLUTION: The cutting tool of a throw-away tip 1, etc., connecting a second contact region 14 and the other end of a sensor line to each other by a second side surface line 16 and a main surface electric conductor 17 provided on a rake face is manufactured by forming the rake face 5 on one main surface side of a base material 2 showing a roughly flat plate shape, a seating a seating surface on the other main surface side 6 and a flank 8 on a side surface crossing the rake face 5, providing the sensor line 12 made of an electrically conductive film having specified width in the neighborhood of a cutting blade 9 of the flank 8 in an electrically insulated state against the base material 2, providing two connecting regions 13, 14 making an electrically connective pair with the specified circuit on the one main surface side and/or the other main surface side of the base material 2 in an electrically insulated state against the base material 2 and connecting the first connecting region 13 and one end of the sensor line 12 by a first side surface line 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting tool such as a throw-away tip used for cutting, and more particularly to a cutting tool with a wear sensor provided with a sensor line for detecting wear of a cutting edge.

[0002]

2. Description of the Related Art Methods for detecting the life of a cutting tool by utilizing thermal, mechanical, and electrical changes of the cutting tool have been studied. For example, in Japanese Patent Application Laid-Open No. 9-38846, a cutting tool having a comb-shaped conductive band (thin film circuit) formed on the surface of a base material is manufactured, and while the cutting tool is being cut, the electric resistance of the conductive band (thin film circuit) is reduced. A method of determining tool life by measuring a value is disclosed.

Further, the present applicant has disclosed, for example, Japanese Patent Application
5, a sensor line 12 is formed near the cutting edge 9 of the flank 8 in parallel with the cutting edge, and a pair of sensor lines 12 are formed at both ends of the sensor line 12 and the seating surface. We propose that a cutting tool that has formed a sensor circuit by connecting the connection area with a connection line (side surface line) formed by drawing a flank can detect cutting edge wear accurately with a simpler circuit pattern line. did.

[0004]

However, in the cutting tool disclosed in Japanese Patent Application No. 2000-329625, a large amount of chips are severely applied to the flank 8 in cutting such as steel turning where a large amount of chips are generated. Because of the collision, the connection line (side surface line) 15 formed on the flank 8 by the impact,
16 may be damaged and may be disconnected in some cases, and accurate detection of the tool life may not be possible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to provide a cutting tool capable of accurately detecting the tool life even with chips during cutting.

[0006]

Means for Solving the Problems The present inventors have studied the wiring of a sensor circuit for the above problems,
By forming one of the two connection lines connecting between both ends of the sensor line and the pair of connection regions on the flank surface, and forming the other on the main surface other than the connection region formation surface such as a rake surface,
In particular, it has been found that a simple sensor circuit can be formed without forming a connection line in an area susceptible to chips, and that the tool life can be accurately detected with little influence of chips.

In other words, the cutting tool of the present invention has a substantially flat base material having a rake face on one main surface, a seating face on the other main face, and a flank face on a side face. In a cutting tool having a cutting edge at the intersection of the flank and a sensor line formed of a conductive band near the cutting edge of the flank, the other main surface can be electrically connected to an external circuit. A conductive layer having a pair of connection regions made of a conductive layer and electrically connecting one of the connection regions and the sensor line, and forming the sensor line and the other of the connection regions on the one main surface. Electrically connected via a main surface conductor layer made of

Here, the one connection region and the sensor line are connected via a first side line made of a conductive band formed on a side surface of the base material, and the main surface conductor layer and the sensor line are connected to each other. It is desirable to connect to the other connection region via a second side line made of a conductive band formed on the side surface of the base material.

Preferably, the pair of connection regions are formed adjacent to each other, and the sensor line is formed near both ends of a side surface of the base material.

Further, a main surface of the base material is formed in a polygonal shape, a plurality of flank surfaces are formed, and the sensor is provided at each corner where the main surface and two adjacent flank surfaces intersect. It is desirable to form a line.

Still further, between the one connection region existing at the intersection ridge portion between the main surface and the side surface of the base material and the first side surface line, between the sensor line and the main surface conductive layer, It is desirable that the height between the main surface conductor layer and the second side surface line and the height between the second side surface line and the other connection region be lower than the height of the other intersection ridge portion. .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1A is a perspective view of a preferred embodiment of a cutting tool according to the present invention as viewed from above, and FIG. 1B is a perspective view as viewed from below. FIG.

According to FIG. 1, a throw-away tip 1
Is a base material 2 having a substantially flat plate shape (a substantially rectangular parallelepiped shape in FIG. 1).
A rake face 5 on one main surface and a seating surface 6 on the other main surface,
A flank 8 is formed on the side surface, and a cutting edge 9 is formed at the intersection between the rake face 5 and the flank 8.

According to FIG. 1, a sensor line 12 made of a conductive band having a predetermined width is provided near the cutting edge 9 of the flank 8.

According to FIG. 1, the sensor line 12 is formed at an end of the flank 8, that is, 0.5 to 2 mm inside the cutting edge 9 and parallel to the cutting edge 9. The degree of sensing of the tool life (amount of wear) can be defined by the forming position and the width. For example, the position of the inner end of the sensor line 12 is determined based on the life reference amount of the cutting edge 9 (the wear limit of the flank 8), for example, 0.05 to 0.7 m
m, and cutting is performed with the cutting blade 9, thereby forming a sensor line 12 formed near the cutting blade 9.
When at least a part of the sensor line is disconnected due to wear, the sensor line is insulated, and the life of the cutting edge 9 is reduced by measuring the resistance value between a pair of connection regions connected to both ends of the sensor line 12 described later. Can be detected.

According to the present invention, for example, a pair of connection regions 13 and 14 made of a conductive layer that can be electrically connected to an external circuit (not shown) are provided on the seating surface 6 (one main surface). The main surface conductor layer 17 made of a conductive layer in which the sensor line 12 is electrically connected to the sensor line 12 and the sensor line 12 and the second connection region 14 are formed on the rake face 5 (the other main surface), for example. It is a great feature that the sensor circuit 10 electrically connected through the connection line is formed. Therefore, the connection line (the second connection) is formed in a portion of the flank 8 such as a nose R, which will be described later, where chips are likely to collide. Since the simple sensor circuit 10 can be formed without forming the line 16), accurate tool life detection can be performed regardless of the influence of chips.

According to the present invention, in order to minimize the influence of chips, the main surface conductor layer 17 is preferably formed over the center of the main surface (the rake surface 5 in FIG. 1).

Further, according to FIG. 1, a pair of connection regions 1
3 and 14 are formed on the seating surface 6 and the main surface conductor layer 17 is formed on the rake surface 5.
0 can be easily connected to a pair of external circuits 26 and 27 formed on a chip holder 20 described later, which is in contact with the seating surface 6.

Further, according to FIG. 1, one connection region 1
3 and the sensor line 12 are connected via a first side line 17 made of a conductive band formed on the side surface (flank surface 8) of the base material 2, and the main surface conductor layer 17 and the second connection region 14 are connected.
Are connected via a second side line 16 composed of a conductive band formed on the flank 8 (side) of the base material 2.
According to FIG. 1, the sensor circuit 10 includes a first connection region 13-a first side line 17-a sensor line 12-
The connection is made through the main surface conductor layer 17 -the second side line 16 -the second connection region 14. Note that the sensor circuit 10 is provided in an insulated state with respect to the base material 2, and the sensor circuit 10 is configured to have a predetermined electric resistance value.

Further, according to FIG. 1, a pair of connection regions (a first connection region 13 and a second connection region 14) are formed adjacent to each other, thereby connecting to the pair of connection regions. External terminals (not shown) can be easily positioned.

Further, according to the present invention, in particular, in a cutting tool in which a throw-away tip or the like can be attached and detached, the sensor line 12 is provided near both ends of the flank 8 (side surface) of the base material 2.
It is desirable that two flank surfaces 8 can be used as cutting blades 9 one after another, that is, two flank surfaces 8 are formed.

That is, as shown in FIG. 1, the main surface of the base material 2 has a polygonal shape (square in FIG. 1), a plurality of flank surfaces 8 (four in FIG. 1) are formed, and It is desirable to form the sensor line 12 at each of the corner portions 19 (eight in FIG. 1) where the two flank surfaces 8 and 8 adjacent to each other intersect, so that the eight corner portions 19 are formed as described later. Can be used for cutting.

According to FIG. 1, the first side line 15 and the second side line 16 formed on the flank 8 are shown.
Are the first and second connection regions 13 of the sensor circuit 10,
14 and the first and second positions of the sensor circuit 10.
The sensor circuit 10 ′ having the first and second connection regions 13 ′ and 14 ′ on the opposite surfaces of the connection regions 13 and 14 of FIG. In order to be able to be connected to the terminals 26 and 27, the sensor line 12 (in other words, with respect to the cutting edge 9) is disposed so as to have a predetermined inclination angle, not an orthogonal direction.

Further, according to the present invention, as shown in FIG. 2, the first ridge existing at the intersection of the main surface (rake face 5 and seating face 6) and side face (flank face 8) of base material 2 is formed. Connection area 13
And the first side line 17, between the sensor line 12 and the main surface conductive layer 17, between the main surface conductor layer 17 and the second side line 16, and between the second side line 16 and the second side line 16. By making the height between the connecting region 14 and the other crossing ridge portions lower, in other words, providing notches in these portions, it is particularly easy to be damaged by handling of the throw-away chip 1 and the like. The line portion can be protected to prevent damage. The shape of the notch may be an R shape, a C surface shape, or a shape depressed in multiple stages.

According to the present invention, the shape of the throw-away tip 1 is not limited to the square of the rake face 5 and the seating face 6 as shown in FIG.
As shown in (1), the main surfaces (rake face 5 and seating face 6) have a shape such as (a) a circle, (b) a regular triangle, (c) a rhombus, or an ellipse, a regular polygon other than the above, or a parallelogram. The cross-sectional shape of the indexable insert 1 is not limited to a rectangular type as shown in (a) to (c) and a so-called negative type insert having cutting edges on both sides. As shown in (d), there may be a trapezoidal shape, and only one side called a so-called positive type is used for cutting.

(Example of Mounting) Further, according to FIG. 1, a clamp hole 11 penetrating through the base material 2 is formed at the center of the base material 2, and the indexable tip 1 of FIG. As shown in an example of the attached FIG. 3, the throw-away tip 1 is screwed into the clamp hole 11 or pressed from the rake face 5 side by a metal fitting (not shown). It is mounted on the chip holder 20 and the like.

According to FIG. 3, a tip mounting pocket 21 is formed at the tip of the tip holder 20. The bottom surface of the pocket 21 is a chip seat 22.
The side surface of the pocket 21 is in contact with the side surface of the chip and serves as a restraining surface 23 for restraining the chip. The throw-away tip 1 is accommodated in the pocket 21, the seating surface 6 is in the tip seat 22, and the side surface of the tip 1 is in the restraining surface 23.
Contacted. Then, the clamp screw 24 is inserted into the clamp hole 11 of the throw-away tip 1 from above,
The tip of the screw hole 25 is formed at the center of the tip seat 22.
The throw-away tip 1 is mounted on the tip holder 20 by being screwed into.

Further, the tip seat 22 is provided at a position facing one of the connection terminals 13 and 14 connected to the sensor line 12 provided at a corner portion used for cutting the mounted throw-away tip 1, for example. A pair of external terminals 26 and 27 which are elastically urged upward and project from the chip seat 22 by several mm are provided in a protruding manner. When the throw-away tip 1 is mounted in the pocket 21, the external terminals 26 and 27 are pushed down by the seating surface 6 of the throw-away tip 1, and the upper ends of the external terminals 26 and 27 are
And become flush. At this time, the upper ends of the external terminals 26 and 27 are in electrical contact with the pair of connection terminals 13 and 14 provided on the seating surface 6 of the throw-away tip 1, respectively.

According to FIG. 3, the external terminals 26, 27
Is connected to a lead wire 28 laid in the chip holder 20 as shown by a thin line.
Is connected to a resistance detection circuit 29 such as an ohmmeter, and thereby a sensor line 12 provided on the cutting edge 9 (corner portion 8 used for cutting) of the throw-away tip 1 attached to the pocket 21. The resistance value can be measured.

In the mounted state shown in FIG. 3, for example, the cutting blade 9 at the corner 19 of the indexable insert 1 is used for cutting. When the cutting edge 9 of the corner portion 19 is worn, the clamp screw 24 and the holding metal are loosened,
Indexable insert 1 centering on the center of the rake face 5
Can be rotated by 90 ° and another corner portion 19 adjacent to the corner portion 19 can be used as a cutting edge 9 for cutting. In this way, the throw-away tip 1 is rotated 90 ° at a time,
The four corner portions on one main surface side of the chip 1 can be sequentially used for cutting. Furthermore, if the throw-away tip 1 is mounted upside down on a holder or the like, the four corners of the other main surface can be used in order for cutting, and a total of eight corners 19 can be used. . When using the corner of the other main surface,
The rake face and the seating face work in reverse.

(Materials) The base material of the indexable insert 1 is an alumina sintered body, a silicon nitride sintered body, a cermet, a cemented carbide, a cubic boron nitride sintered body (CBN /
cubic Boron Nitride), diamond sintered body (PCD / Polycrystallineline)
Diamond) or the like can be suitably used.

The sensor line 12 and the connection line (a pair of connection terminals 13 and 14, the first and second connection lines 1
The conductive band forming the sensor circuit 10, such as 5, 16, the main surface conductor layer 17), has a strong joining force of the throw-away tip 1 to the base material 2, does not react with the work material, and does not react with the work material. The resistance value always shows a predetermined value, the degree of wear of the throw-away tip 1 and the presence or absence of chipping can be accurately detected, reaction products are hardly generated on the machined surface of the work material, oxidation resistance Ti, Z, etc., because the electrical resistance of the sensor line 12 does not change due to the formation of oxide, and the degree of wear of the throw-away tip 1 and the presence or absence of chipping can be accurately detected.
4a, 5a such as r, V, Nb, Ta, Cr, Mo, W, etc.
6a group metal, iron group metal such as Co, Ni, Fe or metal material such as Al, TiC, VC, NbC, TaC,
Cr ₃ C ₂ , Mo ₂ C, WC, W ₂ C, TiN, VN, Nb
N, TaN, CrN, TiCN, VCN, NbCN, T
at least one selected from the group consisting of carbides, nitrides, carbonitrides, and (Ti, Al) N of metals belonging to groups 4a, 5a, and 6a such as aCN and CrCN, particularly TiN, (Ti, Al) N;
At least one member selected from the group of (Ti, Al) CN;
Further, TiN is preferable.

(Preparation Method) In order to form the sensor circuit 10, for example, a predetermined ceramic powder is formed and baked on substantially the entire surface of the base material 2 prepared.
By a known thin film forming method such as a PVD method such as a CVD method, an ion plating, a sputtering, and a vapor deposition, and a plating method, the thickness is controlled to a predetermined thickness, particularly, the adhesion to the base material 2 and a predetermined resistance value. After forming a conductive film having a thickness of about 20 μm, the sensor circuit 10 is processed into a predetermined pattern by laser processing, blast processing using a mask, cutting processing using a drill, or the like.

As a method of forming the sensor circuit 10 by processing, laser processing such as irradiating and scanning a conductive thin film adhered to the surface of the base material 2 with a YAG laser or a CO ₂ laser is fine and precise. It is desirable in that it can form a good line and can cope with various kinds of base materials and coatings. For example, when a YAG laser having a wavelength of 1.06 μm is used, 5 to 50 kHz, an output of 9.0 to 25.0 A, a width of 30 to 60 μm, and a drawing speed of 50 to 300 mm /
It is desirable to perform irradiation scanning at s.

Further, the sensor circuit 10 can be formed directly on the surface of the base material 2 when the base material 2 is an insulator such as an alumina-based sintered body, a silicon nitride-based sintered body, or cBN. When 2 is a conductor such as cemented carbide or cermet, it is desirable to form an intermediate layer made of an insulator such as alumina on the surface of base material 2. The intermediate layer is formed by PVD method or CV method.
Using a known thin film forming method such as Method D, the insulating property is ensured, and 1 to 10 μm
It is desirable to be formed in the thickness of.

[0037]

EXAMPLE A 5 .mu.m-thick intermediate layer made of an insulator was formed on the surface of a base material made of a cemented carbide by a CVD method, and a 0.5 .mu.m-thick TiN thin film was formed by a sputtering method.
Then, a throw-away chip having a sensor circuit having the circuit patterns of FIGS. 1 and 5 was manufactured by laser processing.

The obtained chips were subjected to a cutting test under the following conditions. Work material: FC250 Cutting speed: 240 m / min Depth of cut: 0.5 mm Feed amount 0.35 mm / rev Others: Wet cutting As a result of the above cutting test, in the conventional cutting tool having the sensor circuit of FIG. 40 ~ in all corners
Seventy minutes later, the detection circuit 29 was actuated by determining that the sensor circuit was broken.
Was not broken, and the folded line portion was damaged by the chips and was broken.

On the other hand, in the case of the cutting tool having the sensor circuit shown in FIG. 1, a cutting test was performed at 25 corners. It was confirmed that the sensor line 12 was broken at the corner (nose R).

[0040]

As described in detail above, one of the two connection lines connecting between both ends of the sensor line and the pair of connection regions is a flank surface, and the other is a rake surface or the like other than the connection region forming surface. By forming it on the main surface, it is possible to form a simple sensor circuit without forming a connection line especially in an area susceptible to chips, and to accurately detect tool life without being affected by chips. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of a throw-away insert, which is a preferred example of a cutting tool according to the present invention, as viewed from above (a) and a lower perspective view (b).

FIG. 2 is an enlarged view of the vicinity of a cutting edge of the indexable insert of FIG. 1;

FIG. 3 is a perspective view for explaining an example in which the indexable tip of FIG. 1 is mounted on a tip holder.

FIG. 4 is a diagram (a plan view and a cross-sectional view) for explaining the shape of a throw-away tip, which is a preferred example of the cutting tool of the present invention.

FIG. 5 is a view showing a conventional cutting tool.

[Explanation of symbols]

 1: throw-away tip 2: base material 5: rake face 6: seating face 8: flank face 9: cutting edge 10: sensor circuit 11: clamp hole 12: sensor line 13: first connection area 14: second connection Area 15: first side line 16: second side line 17: main surface conductor layer 19: corner portion 20: chip holder 21: pocket 22: chip seat 23: restraining surface 24: clamp screw 25: screw hole 26: External terminal

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3C029 EE00 3C046 BB01

Claims (6)

[Claims] 1. A rake face is formed on one main surface of a base material having a substantially flat plate shape, a seating surface is formed on the other main surface, and a flank is formed on a side surface, and an intersection ridge between the rake face and the flank is provided. A cutting tool provided with a sensor line formed of a conductive band near the cutting edge on the flank, and a pair of conductive layers electrically connectable to an external circuit on the other main surface. A main surface conductor layer comprising a conductive layer formed on the one main surface while electrically connecting the one connection region and the sensor line and providing the sensor line and the other connection region on the one main surface. A cutting tool electrically connected to the cutting tool. 2. A first conductive band formed on a side surface of the base material between the one connection region and the sensor line.
And a connection between the main surface conductor layer and the other connection region via a second side line made of a conductive band formed on a side surface of the base material. The cutting tool according to claim 1, wherein 3. The cutting tool according to claim 1, wherein the pair of connection regions are formed adjacent to each other. 4. The cutting tool according to claim 1, wherein the sensor line is formed near both ends of a side surface of the base material. 5. A main surface of the base material has a polygonal shape,
5. The sensor line is formed at each corner where a plurality of the flank surfaces are formed and at which two adjacent flank surfaces intersect with the main surface. 6. Cutting tools. 6. The method according to claim 6, wherein the one connection region existing at an intersection ridge portion between the main surface and the side surface of the base material and the first side surface line, the sensor line and the main surface conductive layer, The height between the main surface conductor layer and the second side line and the height between the second side line and the other connection region are set to be lower than the height of the other intersection ridge portion. The cutting tool according to any one of claims 1 to 5, wherein