Patent Application
20240131598
The present invention relates to a cutting tool, and particularly to a cutting tool with a plurality of grooves formed.
Conventionally, a cutting tool with a plurality of grooves formed is known. Such a cutting tool is disclosed in Japanese Patent Laid-Open Publication No. JP 2009-202283, for example.
Japanese Patent Laid-Open Publication No. JP 2009-202283 discloses a cutting tool including a cutting edge formed along a ridge where a rake surface and a relieved surface intersect each other. In the cutting tool disclosed in Japanese Patent Laid-Open Publication No. JP 2009-202283, a wavy shape (a plurality of grooves) is formed on the cutting edge side of the rake surface in a regular arrangement (the grooves are arranged substantially parallel to each other in any direction). In the cutting tool disclosed in Japanese Patent Laid-Open Publication No. JP 2009-202283, because the wavy shape is formed on the rake surface to serve as an oil reservoir for cutting fluid, a frictional resistance between the rake surface and a chip can be reduces when a workpiece is cut, and as a result wearing of the rake surface can be reduced.
Patent Document 1: Japanese Patent Laid-Open Publication No. JP 2009-202283
Although not discussed in Japanese Patent Laid-Open Publication No. JP 2009-202283, the cutting edge of the cutting tool disclosed in Japanese Patent Laid-Open Publication No. JP 2009-202283 will dig into the workpiece, and as a result a part that constantly comes in contact with a chip will exist on the rake surface in proximity to the cutting edge. However, in the cutting tool disclosed in Japanese Patent Laid-Open Publication No. JP 2009-202283, because the grooves are arranged substantially parallel to each other in any direction (arranged adjacent to each other and spaced away from each other), the cutting fluid is unlikely to move between the grooves in the contact part of the rake surface, which constantly comes in contact with a chip, when the workpiece is cut. In other words, the cutting fluid is unlikely to spread in the contact part (in proximity to the cutting edge) of the rake surface, which constantly comes in contact with a chip, the reduction of wearing of the rake surface will be limited. For this reason, in the cutting tool disclosed in Japanese Patent Laid-Open Publication No. JP 2009-202283, there is a problem that its tool life will be reduced by insufficient cutting fluid supplied to the part in proximity to the cutting edge. Also, a similar problem to the rake surface will arise in the relieved surface.
The present invention is intended to solve the above problems, and one object of the present invention is to provide a cutting tool capable of preventing reduction of its tool life caused by insufficient cutting fluid supplied to the part in proximity to its cutting edge.
In order to attain the aforementioned object, a cutting tool according to an aspect of the present invention includes a cutting edge configured to cut a workpiece; a rake surface including a part configured to come in contact with a chip, which appears when the workpiece is cut by the cutting edge; and a relieved surface including a part configured to come in contact with a to-be-cut surface of the workpiece, wherein a plurality of grooves including a plurality of aligned grooves arranged adjacent to each other and a connecting groove connecting at least two of the plurality of aligned grooves to each other are formed on at least one of the cutting edge side of the rake surface and the cutting edge side of the relieved surface.
In the cutting tool according to an aspect of the present invention, as discussed above, a plurality of grooves including a plurality of aligned grooves arranged adjacent to each other and a connecting groove connecting at least two of the plurality of aligned grooves to each other are formed on at least one of the cutting edge side of the rake surface and the cutting edge side of the relieved surface. Accordingly, because the cutting fluid can move through the connection groove between the aligned grooves connected to each other by the connection groove, the cutting fluid can easily spread in a contact part (in proximity to the cutting edge) of the at least one of the rake surface and the relieved surface that will constantly come in contact with a chip as compared with a case in which only aligned grooves are formed without the connection groove. Therefore, it is possible to prevent reduction of the tool life caused by insufficient cutting fluid supplied to the part in proximity to the cutting edge.
In the cutting tool according to the aforementioned aspect, it is preferable that the plurality of grooves are formed on the cutting edge side of the rake surface; and that a groove formation area in which the plurality of grooves are formed extends from the cutting edge side toward a side opposite to the cutting edge on the rake surface. According to this configuration, because the groove formation area extends toward a side opposite to the cutting edge on the rake surface, a part that is out of contact with a chip (a part to which the cutting fluid can be supplied) can be easily provided in the groove formation area. As a result, the cutting fluid can be more easily supplied to the plurality of grooves as compared with a case in which the groove formation area does not extend toward the side opposite to the cutting edge.
In this configuration, the connection groove, which connects the at least two of the plurality of aligned grooves to each other, is preferably arranged on an outer edge of the groove formation area. According to this configuration, because dead ends unlikely to be formed in the plurality of grooves as compared with a case in which the connection groove is located in a central part of the groove formation area, the cutting fluid supplied to the plurality of grooves can spread in a wide area of the groove formation area through the connection groove.
In the configuration in which the connection groove, which connects the at least two of the plurality of aligned grooves to each other, is arranged on an outer edge of the groove formation area, the connection groove, which connects the at least two of the plurality of aligned grooves to each other, is preferably a closure extending along the outer edge so as to surround the groove formation area. According to this configuration, in addition to prevention of such dead end formation, because more aligned grooves can be connected to each other as compared with a case in which the connection groove is formed in a part of the outer edge, the cutting fluid supplied to the plurality of grooves can spread in a wider area of the groove formation area through the connection groove.
In the configuration in which the plurality of grooves are formed on the rake surface, it is preferable that a chip handler configured to bend a chip toward a side opposite to the rake surface on a side opposite to the cutting edge of the groove formation area, and that the groove formation area does not overlap the chip handler on the rake surface. According to this configuration, it is possible to prevent the groove formation area from becoming a complicated structure as compared with a case in which the groove formation area overlaps the chip handler.
In this configuration, it is preferable that the chip handler is arranged in a central part of the rake surface in a direction orthogonal to a direction in which a chip is ejected, and that the groove formation area is formed in a U shape so as to surround the chip handler. According to this configuration, the groove formation area can be easily provided so as not to overlap the chip handler on the rake surface.
In the configuration in which the plurality of grooves are formed on the rake surface, it is preferable that the plurality of aligned grooves extend on the rake surface in a direction intersecting a/the direction in which a chip is ejected. According to this configuration, because an ejected chip is unlikely to stay in the plurality of aligned grooves as compared with a case in which the plurality of aligned grooves extend on the rake surface in the direction in which a chip is ejected, it is possible to prevent reduction of an amount of cutting fluid that can be stored in the plurality of aligned grooves. As a result, the cutting fluid is more likely to stay in an area where the plurality of grooves are formed on the rake surface, and consequently wearing of the rake surface can be effectively reduced.
In this configuration, it is preferable that the plurality of aligned grooves extend on the rake surface in a direction substantially orthogonal to the direction in which a chip is ejected. According to this configuration, because an ejected chip can be reliably prevented from staying in the plurality of aligned grooves, it is possible to reliably prevent reduction of an amount of cutting fluid that can be stored in the plurality of aligned grooves.
In the configuration in which the plurality of grooves are formed on the rake surface, it is preferable that the plurality of grooves have a groove width and a groove depth greater than at least hard particles, which appear between the rake surface and the chip when the workpiece is cut. According to this configuration, hard particles that appear between the rake surface and a chip do not stay outside the grooves and are likely to enter the grooves. As a result, the hard particles are unlikely to dig (ablate) the rake surface, and consequently, wearing of the rake surface can be effectively reduced as compared with a case in which the hard particles, which appear between the rake surface and a chip, do not enter the grooves but stay outside the grooves. The “hard particles, which appear between the rake surface and a chip” refer to pieces of the workpiece that fall from the chip of the workpiece, pieces of the cutting tool that are scratched off the rake surface, etc.
According to the present invention, as discussed above, it is possible to prevent reduction of the tool life caused by insufficient cutting fluid supplied to the part in proximity to the cutting edge.
Embodiments embodying the present invention are hereinafter described on the basis of the drawings.
A cutting tool 100 according to one embodiment of the present invention is now described with reference to
As shown in
The cutting tool 100 has a parallelepiped shape having two bottom surfaces, which has a rhombic shape and arranged parallel to each other, and four side surfaces, which are interposed between the two bottom surfaces. In the following description, a direction in which a longer diagonal line of the bottom surface extends, a direction in which a shorter diagonal line of the bottom surface extends, and a direction in which the sides extend are defined as X, Y and Z directions, respectively. One side in the X, Y and Z directions are defined as X1, Y1, and Z1 sides, respectively, while another side in the X, Y and Z directions are defined as X2, Y2, and Z2 sides, respectively.
In the cutting tool 100, a plurality of vertices (corners 12) of the parallelepiped shape can be used as a cutting edge 20 (described later) for cutting the workpiece 1 (see
As shown in
The cutting edge 20 is formed along a ridge where the rake surface 30 and the relieved surface 40 intersect each other. As shown in
The rake surface 30 includes a part configured to come in contact with a chip 2 that appears when the workpiece 1 is cut by the cutting edge 20. The rake surface 30 extends in a direction (X2 direction) in which the chip 2 is ejected when cutting the workpiece 1. When the workpiece 1 is cut by the cutting tool 100, cutting fluid is supplied to the rake surface 30 from a side (X2 side) opposite to the cutting edge 20.
As shown in
The relieved surface 40 is a surface that includes a part 41 configured to come in contact with a to-be-cut surface 1a of the workpiece 1 when the workpiece 1 is cut.
The relieved surface 40 is formed to extend along the to-be-cut surface 1a when the workpiece 1 is cut. In other words, the relieved surface 40 and the to-be-cut surface 1a extend in the Z direction. When the workpiece 1 is cut by the cutting tool 100, cutting fluid is supplied to the relieved surface 40 from the side (Z2 side) opposite to the cutting edge 20.
Here, in this embodiment, as shown in
Specifically, as shown in
As shown in
A coating 53 is applied on a surface of a base material 52 in the first groove formation area 50 in which the plurality of first grooves 51 are formed. For example, the base material 52 is a cermet or cemented carbide. For example, a titanium compound (titanium carbide, titanium carbo-nitride, etc.), alumina or the like are used for the coating 53.
In this embodiment, as shown in
Specifically, the plurality of aligned grooves 51a extend on the rake surface 30 in a direction (Y direction) substantially orthogonal to the direction (X2 direction) in which the chip 2 is ejected. In other words, the plurality of aligned grooves 51a extend on the rake surface 30 in a direction intersecting the direction in which the chip 2 is ejected (in a direction different from the direction in which the chip 2 is ejected).
In addition, the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is arranged on an outer edge 50a of the first groove formation area 50, and the first groove formation area 50 is formed in a U shape Specifically, the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is a closure extending along the outer edge 50a so as to surround the first groove formation area 50.
In the cutting tool 100, as shown in
Specifically, as shown in
As shown in
The plurality of second grooves 61 are formed by rounded peaks. The “hard particles 3b, which appear between the relieved surface 40 and the to-be-cut surface 1a” refer to pieces of the workpiece 1 that are scratched off the to-be-cut surface 1a, pieces of the cutting tool 100 that are scratched off the relieved surface 40, etc., when the workpiece 1 is cut.
A coating 63 is applied on a surface of a base material 62 in the second groove formation area 60 in which the plurality of second grooves 61 are formed. For example, the base material 62 is a cermet or cemented carbide. For example, a titanium compound (titanium carbide, titanium carbo-nitride, etc.), alumina or the like are used for the coating 63.
The first groove formation area 50 (the plurality of first grooves 51 (the plurality of aligned grooves 51a and the connection groove 51b)) and the second groove formation area 60 (the plurality of second grooves 61) are formed by die molding, laser machining, etc.
In this embodiment, the following advantages are obtained.
In this embodiment, as described above, a plurality of aligned grooves 51a including a plurality of aligned grooves 51a arranged adjacent to each other and a connecting groove 51b connecting at least two of the plurality of aligned grooves 51a to each other are formed on a cutting edge 20 side of the rake surface 30. Accordingly, because the cutting fluid can move through the connection groove 51b between the aligned grooves 51a connected to each other by the connection groove 51b, the cutting fluid can easily spread in a contact part 31 (in proximity to the cutting edge 20) of the rake surface 30 that will constantly come in contact with a chip 2 as compared with a case in which only aligned grooves 51a are formed without the connection groove 51b. Therefore, it is possible to prevent reduction of the tool life caused by insufficient cutting fluid supplied to the part in proximity to the cutting edge 20.
In this embodiment, as discussed above, the plurality of first grooves 51 are formed on the cutting edge 20 side of the rake surface 30. In addition, a first groove formation area 50 in which the plurality of first grooves 51 are formed extends from the cutting edge 20 side toward the side opposite to the cutting edge 20 on the rake surface 30. According to this configuration in which the first groove formation area 50 extends toward the side opposite to the cutting edge 20 on the rake surface 30, a part that is out of contact with a chip 2 (a part to which the cutting fluid can be supplied) can be easily provided in the first groove formation area 50. As a result, the cutting fluid can be more easily supplied to the plurality of first grooves 51 as compared with a case in which the first groove formation area 50 does not extend toward the side opposite to the cutting edge 20.
Also, in this embodiment, as discussed above, the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is arranged on an outer edge 50a of the first groove formation area 50.
Accordingly, because dead ends unlikely to be formed in the plurality of first grooves 51 as compared with a case in which the connection groove 51b is located in a central part of the first groove formation area 50, the cutting fluid supplied to the plurality of first grooves 51 can spread in a wide area of the first groove formation area 50 through the connection groove 51b.
Also, in this embodiment, as discussed above, the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is a closure extending along the outer edge 50a so as to surround the first groove formation area 50. Accordingly, in addition to prevention of such dead end formation, because more aligned grooves 51a can be connected to each other as compared with a case in which the connection groove 51b is formed in a part of the outer edge 50a, the cutting fluid supplied to the plurality of first grooves 51 can spread in a wider area of the first groove formation area 50 through the connection groove 51b.
Also, in this embodiment, as discussed above, a chip handler 32 is provided to bend a chip 2 toward a side opposite to the rake surface 30. In addition, the first groove formation area 50 does not overlap the chip handler 32 on the rake surface 30. Accordingly, it is possible to prevent the first groove formation area 50 from becoming a complicated structure as compared with a case in which the first groove formation area 50 overlaps the chip handler 32.
In this embodiment, as discussed above, the chip handler 32 is arranged in a central part 30a of the rake surface 30 in a direction (Y direction) orthogonal to a direction in which a chip 2 is ejected (X2 direction). In addition, the first groove formation area 50 is formed in a U shape so as to surround the chip handler 32. Accordingly, the first groove formation area 50 can be easily provided so as not to overlap the chip handler 32 on the rake surface 30.
In this embodiment, as discussed above, the plurality of aligned grooves 51a extend on the rake surface 30 in a direction intersecting the direction (X2 direction) in which the chip 2 is ejected. Accordingly, because the ejected chip 2 is unlikely to stay in the plurality of aligned grooves 51a as compared with a case in which the plurality of aligned grooves 51a extend on the rake surface 30 in the direction in which the chip 2 is ejected, it is possible to prevent reduction of an amount of cutting fluid that can be stored in the plurality of aligned grooves 51a. As a result, the cutting fluid is more likely to stay in an area (first groove formation area 50) where the plurality of first grooves 51 are formed on the rake surface 30, and consequently wearing of the rake surface 30 can be effectively reduced.
In this embodiment, as discussed above, the plurality of aligned grooves 51a extend on the rake surface 30 in a direction (Y direction) substantially orthogonal to the direction (X2 direction) in which the chip 2 is ejected. Accordingly, because the ejected chip 2 can be reliably prevented from staying in the plurality of aligned grooves 51a, it is possible to reliably prevent reduction of an amount of cutting fluid that can be stored in the plurality of aligned grooves 51a.
In this embodiment, as discussed above, the plurality of first grooves 51 have a groove width W1 and a groove depth D1 greater than at least hard particles 3a, which appear between the rake surface 30 and the chip 2 when the workpiece 1 is cut. Accordingly, hard particles 3a, which appear between the rake surface 30 and the chip 2, do not stay outside the first grooves 51 and are likely to enter the first grooves 51. As a result, the hard particles 3a are unlikely to dig (ablate) the rake surface 30, and consequently wearing of the rake surface 30 can be effectively reduced as compared with a case in which the hard particles 3a, which appear between the rake surface 30 and the chip 2, do not enter the first grooves 51 but stay outside the first grooves 51.
Note that the embodiment disclosed this time must be considered as illustrative in all points and not restrictive. The scope of the present invention is not shown by the above description of the embodiments but by the scope of claims for patent, and all modifications (modified examples) within the meaning and scope equivalent to the scope of claims for patent are further included.
While the example in which the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is a closure extending along the outer edge 50a so as to surround the first groove formation area 50 has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 200 according to a first modified embodiment of
While the example in which the plurality of aligned grooves 51a extend on the rake surface 30 in a direction (Y direction) substantially orthogonal to the direction
(X2 direction) in which the chip 2 is ejected has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 300 according to a second modified embodiment of
While the example in which the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is arranged on an outer edge 50a of the first groove formation area 50 has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 400 according to a third modified embodiment of
While the example in which the groove formation area 50 is formed in a U shape so as to surround the chip handler 32 has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 500 according to a fourth modified embodiment of
While the example in which the plurality of second grooves 61 extend on the relieved surface 40 from the cutting edge 20 side (Z1 side) to a part in proximity to an edge 40a on a side (Z2 side) opposite to the cutting edge 20 has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 600 according to a fifth modified embodiment of
While the example in which the plurality of second grooves 61 extend on the relieved surface 40 in a cutting direction (Z direction) along which the workpiece 1 is cut by the cutting edge 20 has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 700 according to a sixth modified embodiment of
While the example in which the connection groove 51b, which connects the plurality of aligned grooves 51a to each other, is formed in the first groove formation area 50 has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 800 according to a seventh modified embodiment of
While the example in which the plurality of first grooves 51 are formed on the cutting edge 20 side of the rake surface 30 and the plurality of second grooves 61 are formed on the cutting edge 20 side of the relieved surface has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, as shown in a cutting tool 900 according to an eighth modified embodiment of
While the example in which the cutting tool 100 has a parallelepiped shape has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, the cutting tool may have a shape other than such a parallelepiped shape as long as it has a vertex (corner) that can be used as a cutting edge.
While the example in which the cutting tool 100 is a cutting edge piece (tip) of a tip-replaceable tool to be attached to a tool body has been shown in the aforementioned embodiment, the present invention is not limited to this. The invention may be applied to a cutting tool including a cutting edge (tip) integrally formed with a tool body.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/006892 | 2/24/2021 | WO |
