Variable function edge preparation

Abstract

A cutting insert includes a variable function cutting edge, where the cutting edge has a variable cutting edge height along a length of the cutting edge. The invention further provides a cutting insert comprising a cutting edge having a tip and a depth of cut location, and wherein the cutting edge has a generalized first height, and wherein the cutting edge at the depth of cut location has a second height, and wherein the cutting edge of the tip has a third height, and wherein the second height of the cutting edge at the depth-of-cut location is less than the third height of the cutting edge of the tip of the cutting insert.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] not applicable.

[0003] STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0004] not applicable. Background Art 1. Technical Field

[0005] The present invention provides a cutting insert, the cutting insert comprising a cutting edge, wherein the cutting edge has a variable cutting edge height (or size) and strength along the cutting edge. The present invention provides a cutting insert, the cutting insert comprising a cutting edge having a tip and a cutting depth position, and wherein the cutting depth position is positioned relative to the tip, and wherein the cutting edge has a first height, and wherein the cutting depth position of the cutting edge has a second height, and wherein the tip of the cutting edge has a third height, and wherein the second height of the cutting edge at the cutting depth position is less than the third height of the cutting edge at the tip of the cutting insert. The present invention provides a cutting insert, the cutting insert having a K factor at the cutting edge at the cutting depth position that is higher than the K factor at the cutting edge at the tip of the cutting insert. 2. Background technology

[0007] The background art discloses a cutting insert having a cutting edge with a constant edge height. The background art further describes a cutting insert having a cutting edge and a chip dividing portion, and a cutting insert having an octagonal shaped top surface and an edge portion having a wedge angle that varies from a first angle at a first end of the edge portion to a different angle at a second end of the edge portion. The background art shows a parallelogram shaped cutting insert having a main cutting edge with a variable radial rake angle. The background art describes an indexable cutting insert for a solid drill having four identical cutting edges, wherein the height of the four cutting edges varies over the length of the respective cutting edges.

[0008] The background art does not address the need for a cutting insert having a cutting edge in the region of the cutting depth location with an increased K factor to increase tool life while allowing for a standard edge preparation on the cutting tip of the cutting insert. The present invention addresses the above-mentioned disadvantages of the background art. Summary of the invention

[0009] The present invention provides a variable function edge preparation for a cutting insert. In certain embodiments, a cutting insert includes a cutting edge having a tip and a cutting depth position, wherein the cutting edge has a first end and a second end positioned opposite the first end, and wherein the tip is located at the second end of the cutting edge, and wherein the cutting depth position is positioned opposite the tip and partially extends away from the tip in a direction toward the first end of the cutting insert, and wherein the cutting edge has a first height, and wherein the cutting depth position has a cutting edge with a second height, and wherein the tip has a cutting edge with a third height, and wherein the second height of the cutting edge at the cutting depth position is less than the third height of the cutting edge at the tip of the cutting insert.

[0010] In certain embodiments of the present invention, a cutting blade is provided, which has a base and at least one cutting edge positioned juxtaposed with the base. The cutting edge has a first end and a second end positioned opposite to the first end, and wherein the cutting edge has a length extending from the first end of the cutting edge to the second end of the cutting edge, and wherein the cutting edge has a height measured from the plane of the base of the cutting blade, and wherein the height of the cutting edge varies over the length of the cutting edge. The cutting edge has a tip located at the second end of the cutting blade and a cutting depth position positioned opposite to the tip and extending partially away from the tip in a direction toward the first end of the cutting blade. The height of the cutting edge of the cutting blade at the cutting depth position is less than the height of the cutting edge at the tip of the cutting blade. The present invention provides a cutting blade having a K factor at the cutting edge of the cutting blade at the cutting depth position that is higher than the K factor at the cutting edge at the tip of the cutting blade.

[0011] These and other embodiments of the invention will be described in more detail herein and in the accompanying drawings that show certain embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Although various embodiments of the present invention are shown in the drawings, the specific embodiments shown should not be construed as limiting the claims. Various modifications and changes may be made without departing from the scope of the present invention.

[0013] Figure 1 A top view of a cutting insert having a variable function cutting edge according to the present invention is shown.

[0014] Figure 2 A side view of a cutting insert having a variable function cutting edge according to the present invention is shown.

[0015] Figure 3 A side view of another embodiment of a cutting insert of the present invention having a variable function cutting edge with a large cutting edge radius is shown.

[0016] Figure 4 A side view of another embodiment of a cutting insert having a variable function cutting edge having a linear structure according to the present invention is shown.

[0017] Figure 5 A side view of another embodiment of a cutting insert having a variable-function cutting edge according to the present invention is shown, the variable-function cutting edge having a stepped structure.

[0018] Figure 6 Top views of certain embodiments of the cutting inserts of the present invention are shown.

[0019] Figure 7 The edge radius and the Figure 6 A graph of the K factor at certain locations of the top view.

[0020] Fig. 8A The K factor equation is shown.

[0021] Figure 8B A standard radius honing head with a K factor of 1 is shown.

[0022] Figure 8C An oval honing head with a K factor of 2 is shown. DETAILED DESCRIPTION

[0023] refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 The present invention provides a variable function cutting edge preparation (5) of a cutting insert (1). The cutting insert (1) comprises a cutting edge preparation (5), wherein the cutting edge has a variable cutting edge height (or size) and strength along the cutting edge preparation (5).

[0024] refer to Figure 1 and Figure 2The present invention provides a variable function cutting edge preparation (5) of a cutting insert (1). In certain embodiments of the present invention, a cutting insert (1) is provided, comprising a cutting edge (5) having a tip (7) and a cutting depth position (9), wherein the cutting edge (5) has a first end (11) and a second end (13) positioned opposite to the first end (11), and wherein the tip (7) is located at the second end (13) of the cutting edge (5), and wherein the cutting depth position (9) is positioned opposite to the tip (7) and partially extends away from the tip (7) in a direction toward the first end (11) of the cutting insert (1), and wherein the cutting edge (5) has a first height (20), and wherein the cutting edge (5) of the cutting insert (1) at the cutting depth position (9) has a second height (22), and wherein the cutting edge (5) of the cutting insert (1) at the tip has a third height (22), and wherein the second height (21) of the cutting edge (5) at the cutting depth position (9) is smaller than the third height (22) of the cutting edge (5) located at the tip (7) of the cutting insert (1). In other words, the size of the first height (20) of the cutting edge (5) decreases (i.e. changes) in the direction toward the size of the second height (21) of the cutting edge (5), and the size of the third height (22) of the cutting edge (5) decreases in the direction toward the size of the second height (21) of the cutting edge (5).

[0025] refer to Figure 1 and Figure 2In certain other embodiments of the present invention, there is provided a cutting insert (1), comprising a base (3) and at least one cutting edge (5) positioned juxtaposed to the base (3), wherein the cutting edge (5) has a first end (11) and a second end (13) positioned opposite to the first end (11), and wherein the cutting edge (5) has a length (15) extending from the first end (11) to the second end (13), and wherein the cutting edge (5) has a first height (20) measured from a plane (17) of the base (3), and wherein the first height (20) of the cutting edge (5) varies over the length (15) of the cutting edge (5), and wherein the cutting edge (5) has a cutting tip (7) located at the second end (13) of the cutting insert (1) and a cutting depth position (9) positioned opposite to the cutting tip (7) and extending partially away from the cutting tip (7) in a direction toward the first end (11) of the cutting insert (1), and wherein the cutting edge (5) of the cutting insert (1) at the cutting depth position (9) has a second height (21), and wherein the cutting edge (5) of the cutting insert (1) at the cutting tip (7) has a third height (22), and wherein the second height (21) of the cutting edge (5) at the cutting depth position (9) is smaller than the third height (22) of the cutting edge (5) located at the cutting tip (7) of the cutting edge (5). The present invention provides a cutting insert (1), wherein the K factor of the cutting edge (5) at the cutting depth position (9) is higher than the K factor of the cutting edge (5) at the cutting tip (7) of the cutting insert (1). In such Figure 1 and Figure 6 In certain embodiments of the present invention shown, the cutting edge (5) of the cutting insert (1) at the cutting depth position (9) has a second height (21), which second height is, for example but not limited to, located at 2 mm from a tangent line, the tangent line being located at a third height (reference numeral 22), and wherein the second height (21) of the cutting edge (5) at the cutting depth position (9) is smaller in height than the first height (20) of the cutting edge (5), wherein the first height (20) is, for example but not limited to, located at 1 mm from the tangent line of the cutting edge (5), wherein the tangent line located at reference numeral 22 is juxtaposed with the tip (7) of the cutting edge (5). As used herein, the term "juxtaposition" means placing two or more elements side by side or in close proximity to each other.

[0026] Table 1:

[0027] Location Blade radius k factor (ratio of rake face radius to flank face radius) Blade tip 25 1.2 Tangent 28 1.7 1mm from tangent line 24 1.8 2mm from tangent line 15 2.2

[0028] Figure 6 Top views of certain embodiments of the cutting inserts of the present invention are shown.

[0029] Figure 7The edge radius and the Figure 6 A graph of the K factor at certain locations of the top view.

[0030] As used herein, the term "K factor" means the ratio of the rake face radius to the flank face radius. In other words, the "K factor" is the ratio between the rake face radius and the side face radius, see Fig. 8A By increasing the "K factor", the blade becomes stronger (see Figure 8B and Figure 8C ), thus, increasing tool life in some applications. A higher K factor generally improves the tool life of a cutting insert.

[0031] Cutting tool edge preparation is measured by size and shape. The radius achieved on the rake face and side face can be measured independently to fully define the honing shape. To describe edge shape, the K factor or "K" is often used.

[0032] The higher K factor at the depth of cut location will increase tool life while allowing for a standard radius edge preparation on the tip of the insert. The cutting insert of the present invention allows for the use of standard honing brushes in the manufacture of the variable function edge of the present cutting insert without the need for special elliptical honing brushes or treatments. One of ordinary skill in the art will appreciate that the variation in the cutting edge height of the cutting edge of the cutting insert at the depth of cut location of the present invention compared to the height of the cutting edge at the tip of the cutting insert, combined with the use of a flat brush honing process known in the art, produces an elliptical high K factor honing in the depth of cut location (region) (see Figure 8C ). In order to achieve a higher K factor, the height of the cutting insert at the cutting position depth (ie, the second height) is smaller than the height of the cutting edge at the tip of the cutting insert (ie, the third height). Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 The height of the cutting insert at the depth of the cutting position (i.e., the second height) relative to the height of the cutting edge at the tip of the cutting insert (i.e., the third height, or multiple different heights (see Figure 5 - a decrease (i.e. a change) in multiple step heights. Figure 3 A side view of an embodiment of a cutting insert of the present invention having a variable function cutting edge with a large cutting edge radius is shown. Figure 4 A side view of an embodiment of a cutting insert of the present invention having a variable function cutting edge having a linear structure is shown. Figure 5A side view of an embodiment of a cutting insert of the present invention having a variable function cutting edge in a stepped configuration wherein the height of the cutting edge decreases along the length of the cutting edge insert spanning from the right side of the cutting edge to the left side along the length.

[0033] Those of ordinary skill in the art will appreciate that in some turning operations, a cutting notch of a certain depth may be formed on the cutting insert, which results in failure of the cutting insert. Changing the edge preparation of the cutting insert involves changing the size and shape of the edge hone across the cutting edge of the cutting insert. It is difficult to achieve a significant, controllable difference in edge condition between the tip of the cutting insert and the depth of cut position. The present invention overcomes these difficulties and provides a cutting insert having a variable function cutting edge having a higher K factor at the region of the depth of cut position than at the cutting edge at the tip of the cutting insert.

[0034] As used herein, the terms "including", "containing", etc., in the context of this application, shall be understood to be synonymous with "comprising", and are therefore open-ended and do not exclude the presence of additional undescribed or unlisted elements, materials, phases, or method steps. As used herein, "consisting of" in the context of this application shall be understood to exclude the presence of any unspecified elements, materials, phases, or method steps. As used herein, "consisting essentially of" in the context of this application shall be understood to include the specified elements, materials, phases, or method steps (if applicable), and also include any unspecified elements, materials, phases, or method steps that do not materially affect the basic or novel characteristics of the invention.

[0035] For the purpose of the above description, it should be understood that, except where expressly specified to the contrary, the present invention may employ various alternative variations and step sequences. In addition, all numerals expressing the quantity of components used in, for example, the specification and claims should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise indicated, the numerical parameters set forth are approximate values, which may vary depending on the desired properties sought to be obtained by the present invention. At a minimum, and without attempting to limit the application of the doctrine of equivalents, each numerical parameter should be interpreted at least in view of the number of reported significant figures and by applying general rounding techniques.

[0036] It should be understood that any numerical range stated herein is intended to include all sub-ranges contained therein. For example, the range "1 to 10" is intended to include all sub-ranges between the recited minimum value of 1 and the recited maximum value of 10 (and including the minimum and maximum values), i.e., having a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0037] In this application, unless specifically stated otherwise, the use of the singular includes the plural and the plural includes the singular. In addition, in this application, the use of "or" means "and / or" unless explicitly stated otherwise, even though "and / or" may be explicitly used in certain circumstances. In this application, the articles "a", "an" and "the" include plural referents unless explicitly and obviously limited to one referent.

[0038] While specific embodiments of the present invention have been described above for purposes of illustration, it will be apparent to those skilled in the art that numerous changes in the details of the invention may be made without departing from the invention as defined in the appended claims.

Claims

1. A cutting insert, the cutting insert comprising a cutting edge having a tip and a cutting depth position, wherein the cutting edge has a first end and a second end positioned opposite to the first end, and wherein the tip is located at the second end of the cutting edge, and wherein the cutting depth position is positioned opposite to the tip and partially extends away from the tip in a direction toward the first end of the cutting insert, and wherein the cutting edge has a first height, and wherein the cutting depth position has the cutting edge with a second height, and wherein the tip has the cutting edge with a third height, and wherein the second height of the cutting edge at the cutting depth position is less than the third height of the cutting edge at the tip of the cutting insert.

2. The cutting insert of claim 1, wherein the first height has a drop between the second height and the third height.

3. The cutting insert of claim 2, wherein the drop in the first height between the second height and the third height is stepped, linear, or on a radius of the cutting edge.

4. The cutting insert according to claim 1, wherein a K factor of the cutting insert at the cutting edge at the cutting depth position is higher than a K factor at the cutting edge at the tip of the cutting insert.

5. A cutting blade, wherein the cutting blade includes a base and at least one cutting edge positioned juxtaposed with the base, and wherein the cutting edge has a first end and a second end positioned opposite to the first end, and wherein the cutting edge has a length extending from the first end to the second end, and wherein the cutting edge has a first height measured from the plane of the base, and wherein the first height of the cutting edge varies over the length of the cutting edge, and wherein the cutting edge has a tip located at the second end of the cutting blade and a cutting depth position positioned opposite to the tip and extending partially away from the tip in a direction toward the first end of the cutting blade, and wherein the cutting edge of the cutting blade at the cutting depth position has a second height, and wherein the cutting edge of the cutting blade at the tip has a third height, and wherein the second height of the cutting edge at the cutting depth position is smaller than the third height of the cutting edge at the tip of the cutting blade.

6. The cutting insert of claim 5, wherein the first height has a drop between the second height and the third height.

7. The cutting insert of claim 6, wherein the drop in the first height between the second height and the third height is stepped, linear, or on a radius of the cutting edge.

8. The cutting insert of claim 6, wherein a K factor of the cutting insert at the cutting edge at the cutting depth position is higher than a K factor at the cutting edge at the tip of the cutting insert.

9. A cutting insert comprising a variable function cutting edge, wherein the cutting edge has a variable cutting edge height along the length of the cutting edge.

10. The cutting insert of claim 9, wherein the cutting edge is made of a material having variable strength along the length of the cutting edge.

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