Patent Grant
7905687
The present disclosure is directed to cutting inserts and tool holders for replaceable and indexable cutting inserts. In one non-limiting embodiment, cutting inserts according to the present disclosure are particularly useful in peripheral rotary milling applications for machining difficult-to-machine materials.
Cutting inserts suffer from a limited service life in peripheral rotary milling applications, especially when machining difficult-to-machine materials. Difficult-to-machine materials include, for example, specialty metals such as titanium and titanium alloys, nickel and nickel alloys, superalloys, and certain exotic metals. Cutting inserts comprising a positive rake face geometry on both the axial cutting face and the radial cutting face are commonly employed in milling operations involving the use of a peripheral rotary tool holder with an indexable capability. The positive cutting geometry of the inserts reduces the cutting forces and consequently reduces power consumption, resulting in a more efficient milling operation. In addition, the cutting inserts typically used in peripheral rotary milling are generally parallelogram-shaped (i.e., each has a generally parallelogram-shaped profile when viewed from a point above the insert's top surface), with two long sides forming two main cutting edges and two short sides forming two minor cutting edges. These types of cutting inserts provide more efficient machining by providing the capability of a larger depth of cut, though such inserts are not as strong as square-shaped cutting inserts.
European Patent No. 0 239 045 provides a parallelogram-shaped cutting insert having a constant positive radial rake angle and a constant radial clearance angle along the major cutting edges.
U.S. Pat. No. 5,071,292 describes a parallelogram-shaped cutting insert having a continuous curved radial cutting face and radial clearance face wherein both the radial rake angle and the radial clearance angle remain substantially the same along the main cutting edge with respect to the associated cutter or tool holder.
U.S. Pat. No. 5,052,863 provides a method for securely locating a parallelogram-shaped cutting insert having a relatively large positive radial clearance angle along the main cutting edge in a tool holder. The method involves adapting a tool holder designed to accommodate an insert having a lower radial clearance angle, to overcome the strength problems associated with greater unsupported overhang when using the parallelogram-shaped cutting inserts having larger radial clearance angle.
U.S. Pat. No. 5,388,932 describes an angled chamfer at the elevated corner nose area of a parallelogram-shaped cutting insert, wherein the angled chamfer increases the cutting edge strength at the main corner nose while maintaining a positive radial rake angle along the main cutting edge.
U.S. Pat. No. 6,142,716 also describes an angled chamfer with a positive radial rake angle, but further comprises a recess at the major cutting sides enabling more rigid localization of the cutting insert in the tool holder and use of less material in manufacturing the cutting insert.
Efforts in the industry to develop new or improved parallelogram-shaped cutting inserts have been directed toward achieving reduced cutting forces, reduced power consumption, increased cutting edge strength, and increased tool life. From the point view of geometrical design, maintaining a positive or a positive plus constant radial rake angle along the main cutting edge has been a fundamental goal of these efforts.
The position of the cutting insert in the associated tool holder may also contribute to achieving the goals of reducing cutting forces and increasing cutting edge strength. Known patent publications and published literature regarding parallelogram-shaped cutting inserts including those described above do not recognize a quantitative relationship between the cutting insert geometry and the position of the cutting insert in the associated tool holder.
Therefore, there is a need for an improved parallelogram-shaped cutting insert and for a milling cutting tool system including plural cutting inserts and a tool holder providing a more efficient and more effective method for machining difficult-to-machine materials.
According to one non-limiting aspect of the present disclosure, a generally parallelogram-shaped cutting insert is provided, comprising: a top face; first and second main radial clearance faces, each intersecting the top face; first and second minor axial clearance faces each intersecting the top face and connecting the first and second main radial clearance faces; and a main cutting edge at the intersection of the top face and the first main radial clearance face. According to one non-limiting embodiment, the main cutting edge comprises a variable radial rake angle including a portion having a positive radial rake angle and a portion having a negative radial rake angle.
According to another non-limiting aspect of the present disclosure, a peripheral cutting tool is provided comprising a tool holder including at least one insert pocket. A cutting insert may be located in the at least one insert pocket of the tool holder such that a midpoint of the main cutting edge of the cutting insert is located in a radial plane comprising the axis of rotation of the tool holder, and wherein a support plane including a bottom surface of the insert pocket is perpendicular to a secondary radial plane. The secondary radial plane comprises the axis of rotation of the tool holder and is perpendicular to the primary radial plane.
According to yet another non-limiting aspect of the present disclosure, a method is provided for positioning a cutting insert comprising a main cutting edge in an insert pocket of a tool holder of peripheral cutting tool. The method comprises positioning the cutting insert in the insert pocket so that a midpoint of the main cutting edge is located in a primary radial plane comprising the axis of rotation of the tool holder, and wherein a support plane including a bottom surface of the insert pocket is perpendicular to a secondary radial plane that comprises the axis of rotation of the tool holder and is perpendicular to the primary radial plane.
Certain non-limiting embodiments according to the present disclosure will be understood by reference to the following figures, wherein:
a, 3b, 3c, and 3d are views illustrating features of one non-limiting embodiment of a parallelogram-shaped cutting insert according to the present disclosure;
a, 4b, 4c, 4d, 4e, and 4f are various views illustrating the pattern of radial rake angles along the main cutting edge and axial rake angles along the minor cutting edge for one non-limiting embodiment of a parallelogram-shaped cutting insert according to the present disclosure;
a is a side view and
a is a side view and
The reader will appreciate the foregoing details, as well as others, upon considering the following detailed description of certain non-limiting embodiments of apparatus and methods according to the present disclosure. The reader also may comprehend certain of such additional details upon carrying out or using the apparatus and methods described herein.
In the present description of non-limiting embodiments and in the claims, other than in the operating examples or where otherwise indicated, all numbers expressing quantities or characteristics of ingredients and products, processing conditions, and the like are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, any numerical parameters set forth in the following description and the attached claims are approximations that may vary depending upon the desired properties one seeks to obtain in the apparatus and methods according to the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein is only incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.
Cutting tool life becomes a critical factor in efficient peripheral rotary milling applications for machining difficult-to-machine materials, particularly specialty metals. Parallelogram-shaped cutting inserts are typically used in peripheral rotary milling due to their relatively large depth of cut obtained by the relatively longer main cutting edge as compared to square cutting inserts. The longer main cutting edge, however, increases the load on the cutting insert. To effectively overcome the increased cutting edge load problems while providing an efficient positive cutting action for applications involving machining difficult-to-machine materials, there is a need for an improved design of a cutting tool system including parallelogram-shaped cutting inserts and an associated tool holder.
Certain non-limiting embodiments according to the present disclosure include a generally parallelogram-shaped cutting insert comprising: a top face; first and second main radial clearance faces, each intersecting the top face; first and second minor axial clearance faces, each intersecting the top face and connecting the first and second main radial clearance faces; and a main cutting edge at the intersection of the top face and the first main radial clearance face. Certain non-limiting embodiments may further comprise a variable radial rake angle along the length of the main cutting edge comprising a portion having a positive radial rake angle and a portion having a negative radial rake angle. The variable radial rake angle of the cutting insert changes, preferably gradually, from a positive radial rake angle to a negative radial rake angle. The result is that in certain embodiments, the radial rake angle near the main cutting corner is positive, and the radial rake angle near the minor cutting corner is negative. Such a design provides a stronger cutting edge with a longer service life than a parallelogram-shaped cutting insert having a positive radial rake angle across the entire cutting edge.
Certain non-limiting embodiments of a parallelogram-shaped cutting insert according to the present disclosure comprise a main corner nose. The main corner nose provides a significant portion of the active cutting action by the cutting insert. In certain non-limiting embodiments, the portion of the main cutting edge comprising the positive radial rake angle is longer than the portion of the main cutting edge comprising the negative radial rake angle. Also, in certain non-limiting embodiments, the portion of the main cutting edge comprising a positive radial rake angle is at least three times longer than the portion of the main cutting edge comprising a negative radial rake angle. In yet other non-limiting embodiments, the portion of the main cutting edge comprising a positive radial rake angle is at least seven times longer than the portion of the main cutting edge comprising a negative radial rake angle. Non-limiting cutting insert embodiments according to the present disclosure comprise at least one point wherein the radial rake angle is zero, and one of the points having a zero rake angle is between the portion of the main cutting edge comprising the positive radial rake angle and the portion of the main cutting edge comprising the negative radial rake angle.
Parallelogram-shaped cutting inserts are typically indexable and often comprise a first main cutting edge at the intersection of the top face and the first main radial clearance face and a second cutting edge at the intersection of the top face and the second main radial clearance face. In certain non-limiting embodiments according to the present disclosure, each cutting edge comprises a variable radial rake angle along the length of the cutting edge, comprising a portion having a positive radial rake angle and a portion having a negative radial rake angle.
Typical parallelogram-shaped cutting inserts are significantly more complicated than those shown in
The effective cutting length of the cutting insert 27 is defined as the length (LE) as shown in
Cutting insert 27 has multiple (i.e., at least two) clearance faces below each of the cutting edges at the top face 28. In particular, the first axial clearance face 41, or the facet face, below the first portion of the minor cutting edge (35a or 35b) functions as a wiper contact face to improve the surface finish of the work materials in peripheral rotary milling operations (see
As illustrated in
On the main side of the embodiment of the cutting insert 27 shown in
Another feature of the embodiment shown as cutting insert 27 is illustrated in the various cross-sectional views of
LN<LTOP/4,
ØRR-X>0, if Lx<LTOP−LN
ØRR-X=0, if Lx=LTOP−LN
ØRR-X<0, if Lx>LTOP−LN Eq. (1)
where Lx is the length measured in the top view plane from the facet edge 65a to the point X along the main cutting edge where the radial rake angle ØRR-X is measured.
The above relationships are illustrated by the cross-sectional views of
In addition to improving the geometry of a cutting insert, a milling cutting tool system for machining difficult-to-machine materials may also be improved by modifying the associated tool holder to optimize how a parallelogram-shaped cutting insert is positioned in the insert pocket. In certain embodiments according to the present disclosure, a tool holder is provided that maintains a certain quantitative relationship between the geometry of a parallelogram-shaped cutting insert and its position in the associated tool holder to thereby provide balanced and optimized cutting performance for the cutting inserts and the tool holder.
A non-limiting embodiment of a milling cutting tool system 80 according to the present disclosure including multiple parallelogram-shaped cutting inserts 81a, 81b, 81c, 81d, 81e, 81f, 81g seated in a tool holder 82 is shown in
Certain non-limiting embodiments of a peripheral cutting tool according to the present disclosure comprise a tool holder comprising at least one insert pocket. The tool holder may have more than one insert pocket and typically comprises from 2-25 insert pockets. A cutting insert must be attached in each pocket. In one embodiment, the cutting insert comprises a main cutting edge. The inventors have found that the cutting operation may be performed more efficiently if the cutting insert is positioned in the insert pocket of the tool holder such that a midpoint of the main cutting edge is located in a radial plane comprising the axis of rotation of the tool holder. For example, as illustrated in
Through a thorough study, the inventors surprisingly found that a more balanced and efficient milling operation can be achieved by positioning the cutting inserts in a tool holder in the above-described manner, which can also be mathematically expressed by the following set of equations. For example, the best performance is achieved in machining difficult-to-machine specialty metals when a cutting insert wherein the rake angles are designed according to the several equations of above Eq. (1) is seated in the associated tool holder. Such a position for the parallelogram-shaped cutting inset can be mathematically defined by applying the following set of equations. The projected side view shown in
L1=L2=L/2 Eq. (2)
where, as shown at the Magnified View in
The second equation is to set an equalized radial cutting angle to position each parallelogram-shaped cutting insert, for instance cutting insert 131, in the associated tool holder 132, as shown in the front-end and magnified insert views of
ØRC-D1=ØRC-D2 Eq. (3)
where ØRC-D1 is the radial cutting angle formed between the cutting edge start point D1 in the radial plane with the center at P and the radial center line 133, and ØRC-D2 is the radial cutting angle formed between the cutting edge end point D2 in the radial plane with the center at P and the radial center line 133. A reasonable manufacturing tolerance also applies to the above equation.
When the parallelogram-shaped cutting inserts are designed based on above Eq. (1) and positioned in the associated tool holder according to above Eqs. (2) and (3), improved results can be achieved, including improved stability, balanced performance between cutting efficiency and edge strength, and prolonged tool life in applications of machining difficult-to-machine materials.
Furthermore, certain non-limiting embodiments according to the present disclosure relate to multiple parallelogram-shaped cutting inserts and an associated tool holder. It will be understood, however, that inserts and tool holders within the scope of the present disclosure may be embodied in forms and applied to end uses that are not specifically and expressly described herein. For example, one skilled in the art will appreciate that embodiments within the scope of the present disclosure and the following claims may be manufactured as cutting inserts and/or tool holders adapted for other methods of removing metal from all types of work materials.
Certain non-limiting embodiments according to the present disclosure are directed to parallelogram-shaped cutting inserts providing a combination of advantages exhibited by varying the radial rake angle along the main cutting edge to achieve balanced and optimal performance between efficient cutting action and an enhanced cutting edge. The parallelogram-shaped cutting inserts described herein may be of conventional size and adapted for conventional use in a variety of machining applications. Certain other embodiments according to the present disclosure are directed to a tool holder and a unique and quantitative method to determine how to position parallelogram-shaped cutting inserts in the tool holder to achieve optimized performance for the cutting inserts and the tool holder as an entity.
It will be understood that the present description illustrates those aspects of the invention relevant to a clear understanding of the invention. Certain aspects that would be apparent to those of ordinary skill in the art and that, therefore, would not facilitate a better understanding of the invention have not been presented in order to simplify the present description. Although only a limited number of embodiments of the present invention are necessarily described herein, one of ordinary skill in the art will, upon considering the foregoing description, recognize that many modifications and variations of the invention may be employed. All such variations and modifications of the invention are intended to be covered by the foregoing description and the following claims.
The present application claims priority under 35 U.S.C. §119(e) to co-pending U.S. provisional patent application Ser. No. 60/885,053, filed Jan. 16, 2007.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3399442 | Jones et al. | Sep 1968 | A |
| 3557416 | Jones | Jan 1971 | A |
| 3621549 | Billups | Nov 1971 | A |
| 3806713 | Ryberg | Apr 1974 | A |
| 4274766 | Raupp et al. | Jun 1981 | A |
| 4294565 | Erkfritz | Oct 1981 | A |
| 4461602 | Zettl | Jul 1984 | A |
| 4493596 | Grunsky et al. | Jan 1985 | A |
| 4595322 | Clement | Jun 1986 | A |
| 4659264 | Friedline | Apr 1987 | A |
| 4681488 | Markusson | Jul 1987 | A |
| 4699549 | Shimomura et al. | Oct 1987 | A |
| 4760548 | Baker et al. | Jul 1988 | A |
| 4940369 | Aebi et al. | Jul 1990 | A |
| 5052863 | Satran | Oct 1991 | A |
| 5071292 | Satran | Dec 1991 | A |
| 5092718 | Shallenberger | Mar 1992 | A |
| 5094572 | Alsbury et al. | Mar 1992 | A |
| 5137398 | Omori et al. | Aug 1992 | A |
| 5145295 | Satran | Sep 1992 | A |
| 5193946 | Arai et al. | Mar 1993 | A |
| 5203649 | Katbi et al. | Apr 1993 | A |
| 5226761 | Satran et al. | Jul 1993 | A |
| 5244318 | Arai et al. | Sep 1993 | A |
| 5246315 | Hansson et al. | Sep 1993 | A |
| 5333972 | Bernadic et al. | Aug 1994 | A |
| 5338135 | Noguchi et al. | Aug 1994 | A |
| 5340246 | Tukala | Aug 1994 | A |
| 5346336 | Rescigno | Sep 1994 | A |
| 5377116 | Wayne et al. | Dec 1994 | A |
| 5388932 | DeRoche et al. | Feb 1995 | A |
| 5408598 | Pryor, Jr. | Apr 1995 | A |
| 5443335 | Shimano et al. | Aug 1995 | A |
| 5454670 | Noda et al. | Oct 1995 | A |
| 5474407 | Rodel et al. | Dec 1995 | A |
| 5586843 | Minicozzi | Dec 1996 | A |
| 5593255 | Satran et al. | Jan 1997 | A |
| 5634745 | Wiman et al. | Jun 1997 | A |
| 5658100 | Deiss et al. | Aug 1997 | A |
| 5688081 | Paya | Nov 1997 | A |
| 5725334 | Paya | Mar 1998 | A |
| 5762453 | Arai et al. | Jun 1998 | A |
| 5791831 | Shimano et al. | Aug 1998 | A |
| 5791833 | Nielbauer | Aug 1998 | A |
| 5791883 | Ban et al. | Aug 1998 | A |
| 5803674 | Satran et al. | Sep 1998 | A |
| 5951212 | Emoto et al. | Sep 1999 | A |
| 5957629 | Hessman et al. | Sep 1999 | A |
| 5957635 | Nuzzi et al. | Sep 1999 | A |
| 5971676 | Kojima | Oct 1999 | A |
| 6050752 | DeRoche | Apr 2000 | A |
| 6053671 | Stedt et al. | Apr 2000 | A |
| 6100904 | Gupta | Aug 2000 | A |
| 6142716 | Jordberg et al. | Nov 2000 | A |
| 6152658 | Satran et al. | Nov 2000 | A |
| 6186705 | Kumar et al. | Feb 2001 | B1 |
| 6238133 | DeRoche et al. | May 2001 | B1 |
| 6244791 | Wiman et al. | Jun 2001 | B1 |
| 6270297 | Fang et al. | Aug 2001 | B1 |
| 6540448 | Johnson | Apr 2003 | B2 |
| 6543970 | Qvarth et al. | Apr 2003 | B1 |
| 6623217 | Brockett et al. | Sep 2003 | B2 |
| 6655881 | Shimizu | Dec 2003 | B2 |
| 6669412 | Hirose et al. | Dec 2003 | B1 |
| 6684742 | White | Feb 2004 | B1 |
| 6715967 | Wiman et al. | Apr 2004 | B2 |
| 6722824 | Satran et al. | Apr 2004 | B2 |
| 6769844 | Waggle | Aug 2004 | B2 |
| 6835028 | Usui et al. | Dec 2004 | B2 |
| 6884006 | Nagashima | Apr 2005 | B2 |
| 6921233 | Duerr et al. | Jul 2005 | B2 |
| 6929427 | Satran | Aug 2005 | B2 |
| 6929429 | Riviére | Aug 2005 | B2 |
| 6957935 | Sung et al. | Oct 2005 | B2 |
| 6960049 | Inayama | Nov 2005 | B2 |
| 7037051 | Wermeister | May 2006 | B2 |
| 7070363 | Long, II et al. | Jul 2006 | B2 |
| 7220083 | Festeau et al. | May 2007 | B2 |
| 7232279 | Smilovici et al. | Jun 2007 | B2 |
| 7234899 | Fang et al. | Jun 2007 | B2 |
| 7241082 | Smilovici et al. | Jul 2007 | B2 |
| 7281884 | Maeda | Oct 2007 | B2 |
| 7306409 | Stabel et al. | Dec 2007 | B2 |
| 7325471 | Massa et al. | Feb 2008 | B2 |
| 7393163 | Edvardsson et al. | Jul 2008 | B2 |
| 20030031520 | Hintze et al. | Feb 2003 | A1 |
| 20030206777 | Gyllengahm | Nov 2003 | A1 |
| 20030226694 | Moseley | Dec 2003 | A1 |
| 20060115340 | Nishio et al. | Jun 2006 | A1 |
| 20060245837 | Dufour et al. | Nov 2006 | A1 |
| 20070189864 | Festeau et al. | Aug 2007 | A1 |
| 20090097929 | Festeau et al. | Apr 2009 | A1 |
| 20090279962 | Dufour et al. | Nov 2009 | A1 |
| 20100080662 | Satran et al. | Apr 2010 | A1 |
| 20100183386 | Heinloth et al. | Jul 2010 | A1 |
| 20100202839 | Fang et al. | Aug 2010 | A1 |
| Number | Date | Country |
|---|---|---|
| 1041499 | Jan 1999 | CN |
| 1041901 | Feb 1999 | CN |
| 1045557 | Oct 1999 | CN |
| 13879970 | Jan 2003 | CN |
| 1117646 | Aug 2003 | CN |
| 4118070 | Feb 1995 | DE |
| 4400538 | Jul 1995 | DE |
| 0035848 | Feb 1985 | EP |
| 0285660 | Oct 1988 | EP |
| 0239045 | Oct 1990 | EP |
| 1157768 | Nov 2001 | EP |
| 1205877 | May 2002 | EP |
| 1346789 | Nov 2006 | EP |
| 1749602 | Feb 2007 | EP |
| 2364724 | Apr 1978 | FR |
| 2298600 | Sep 1996 | GB |
| 52-103081 | Aug 1977 | JP |
| 59-214501 | Dec 1984 | JP |
| 5-285708 | Nov 1993 | JP |
| 8-039329 | Feb 1996 | JP |
| 8-174237 | Jul 1996 | JP |
| 2002-301603 | Oct 2002 | JP |
| 2003-275920 | Sep 2003 | JP |
| 344930 | Aug 1972 | SU |
| 814573 | Mar 1981 | SU |
| 1504006 | Aug 1989 | SU |
| WO 9221467 | Dec 1992 | WO |
| WO 9412302 | Jun 1994 | WO |
| WO 9500272 | Jan 1995 | WO |
| WO 9532071 | Nov 1995 | WO |
| WO 9635538 | Nov 1996 | WO |
| WO 0218083 | Mar 2002 | WO |
| WO 02102536 | Dec 2002 | WO |
| WO 03099495 | Dec 2003 | WO |
| WO 2004096474 | Nov 2004 | WO |
| WO 2006041353 | Apr 2006 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20080170919 A1 | Jul 2008 | US |
| Number | Date | Country | |
|---|---|---|---|
| 60885053 | Jan 2007 | US |
