KR102611096B1 - Cutting tool with porous internal cooling channel - Google Patents

Abstract

One embodiment of the present invention provides a cutting tool having an internal cooling channel with a porous structure. A cutting tool having an internal cooling channel of a porous structure according to an embodiment of the present invention includes a core portion; A core cooling channel provided in the center of the core portion; A cutter provided on the outside of the core portion; A cutter cooling channel provided in the cutter and extending to the outer surface of the cutter; and a connection channel connecting the core cooling channel and the cutter cooling channel, wherein the core cooling channel, the cutter cooling channel, and the connection channel are formed as the core portion and the cutter are formed by metal 3D printing.

Description

Cutting tool with internal cooling channel of porous structure {CUTTING TOOL WITH POROUS INTERNAL COOLING CHANNEL}

The present invention relates to a cutting tool having an internal cooling channel of a porous structure, and more specifically, to a cutting tool having an internal cooling channel of a porous structure in which a cooling channel is provided inside the tool.

In general, machine tools are used to process metal workpieces into desired shapes and dimensions using appropriate tools using various cutting or non-cutting processing methods, such as computerized numerical control (CNC) lathes or semi-automatic machines. There are types of NC machines or machining centers.

These machine tools are equipped with a cutting tool that performs cutting and a tool holder that is coupled to the spindle, connects the spindle and the tool, and is a device that holds the tool.

Meanwhile, cutting tools such as existing solid end mills and drills are made by processing metal materials suitable for use as cutting tools, and have a completely solid structure in which cutting oil is supplied to the outside to cool cutting heat, and a cooling system that can supply cutting oil. There is a hollow structure with a hollow channel inside.

First, a cutting tool with a completely solid structure in which cutting oil is supplied from the outside mainly cools the cutting heat generated on the outer surface of the cutting edge, so it is difficult to dissipate the cutting heat transmitted to the inside of the cutting edge.

Next, in a cutting tool with a hollow structure in which cutting oil is supplied internally, cutting oil can be supplied not only to the outside but also to the inside, further cooling the cutting heat that may be generated during cutting, but processing the cooling channel. Due to limitations, it is difficult to sufficiently supply cutting oil to the area adjacent to the cutting edge.

In other words, the cooling channel formed in the existing cutting tool is formed by drilling in the center of the cutting tool or its surroundings, so it is difficult to form it near the cutting edge where cutting heat is concentrated, and furthermore, it is difficult to form it near the cutting edge where cutting heat is concentrated. It is almost impossible to machine and form the channel cross section.

As such, the cooling performance of existing cutting tools is not high enough for the cutting edge area where cutting heat is concentrated, so thermal deformation of the cutting surface occurs due to deterioration of the cutting edge and cutting chips during high-speed machining, or thermal deformation of the cutting tool occurs. Additionally, cutting tools have to be frequently replaced due to fatigue or breakage, or equipment repairs occur frequently, resulting in increased tact time of the cutting process and decreased productivity.

Korean Patent No. 10-1917269

The purpose of the present invention to solve the above problems is to apply 3D printing technology to cutting tools to form a cutting channel cavity as close to the cutting edge of the cutting tool as possible, thereby improving cooling performance for the cutting edge compared to existing cutting tools. The aim is to provide a cutting tool that has an internal cooling channel with a porous structure that can sufficiently increase cutting precision, stability, and productivity in high-speed machining.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

The configuration of the present invention for achieving the above object includes a core portion; a core cooling channel provided in the center of the core portion; A cutter provided outside the core portion; a cutter cooling channel provided in the cutter and extending to an outer surface of the cutter; and a connection channel connecting the core cooling channel and the cutter cooling channel, wherein the core cooling channel, the cutter cooling channel, and the connection channel are formed as the core portion and the cutter are formed by metal 3D printing. It is characterized by

In an embodiment of the present invention, the cutter has a rake face corresponding to the cutting surface and a flank face corresponding to guidance of the cutting chip, and the cutter cooling channel provides a greater flow rate toward the rake face than the flank face. It can be arranged to do so.

In an embodiment of the present invention, the cutter cooling channel includes a plurality of rake capillary channels extending from the connection channel toward the rake face; And it may include a plurality of flank capillary channels extending from the connection channel toward the flank face.

In an embodiment of the present invention, the connecting channel is formed radially in the core cooling channel toward the flank face side, and in the connecting channel, the rake capillary channel is disposed inclined toward the rake face side, and in the connecting channel, the rake capillary channel is disposed radially toward the flank face side. The flank capillary channel may be disposed inclined toward the flank face.

In an embodiment of the present invention, two or more rake capillary channels may be arranged, and one or more flank capillary channels may be arranged.

In an embodiment of the present invention, the rake capillary channel may have a wider channel width than the flank capillary channel.

In an embodiment of the present invention, the cutter, cutter cooling channel, and connection channel are provided in a plurality of spiral shapes along the outer peripheral surface of the core portion, and the core portion, cutter, cutter cooling channel, connection channel, and core cooling The channel may be formed of metal stacks along the central axis of the core.

The effect of the present invention according to the above configuration is to sufficiently increase the cooling performance of the cutting edge compared to existing cutting tools by applying 3D printing technology to the cutting tool to form a cutting channel cavity as close to the cutting edge of the cutting tool as possible. It provides a cutting tool with an internal cooling channel with a porous structure that can increase cutting precision, stability, and productivity in high-speed machining.

The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

Figure 1 is a front view of a cutting tool having an internal cooling passage of a porous structure according to an embodiment of the present invention.
Figure 2 is a cross-sectional view taken along line I-I of Figure 1.

Hereinafter, the present invention will be described with reference to the attached drawings. However, the present invention may be implemented in various different forms and, therefore, is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to be "connected (connected, contacted, combined)" with another part, this means not only "directly connected" but also "indirectly connected" with another member in between. "Includes cases where it is. Additionally, when a part is said to “include” a certain component, this does not mean that other components are excluded, but that other components can be added, unless specifically stated to the contrary.

The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to indicate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a front view of a cutting tool having an internal cooling passage of a porous structure according to an embodiment of the present invention, and Figure 2 is a cross-sectional view taken along line I-I of Figure 1.

Referring to FIGS. 1 and 2, the cutting tool 100 having an internal cooling channel of a porous structure according to an embodiment of the present invention includes a core portion 101 and a core cooling channel provided in the central portion of the core portion 101. (105), a cutter 120 provided on the outside of the core portion 101, a cutter cooling channel 125 provided on the cutter 120 and extending to the outer surface of the cutter 120, and the core cooling channel 105 and the cutter. It includes a connection channel 130 connecting the cooling channel 125.

The core portion 101 is formed as the central structure of the tool to which the cutter 120 is coupled, and is a hollow structure with a core cooling channel 105 penetrating the center in the longitudinal direction.

The core cooling channel 105 is a passage through which cooling fluid, such as cutting oil, is supplied for cooling the core portion 101, and is presented in a circular cross-sectional shape as shown, but is not limited thereto, and is intended to increase the heat exchange area. It may have an uneven shape for

In the core cooling channel 105, the cooling fluid flows along the center line of the core portion 101.

As the cooling fluid, a fluid or gas used to cool the core portion 101 by passing through the core cooling channel 105 and exchanging heat with the core portion 101 may be used.

The cutter 120 is formed at regular intervals on the core portion 101 to cut the cutting object, and an edge portion 121 that is sharply machined and heat treated for cutting is provided.

For example, the cutter 120 may have a spiral structure arranged at 90- or 180-degree intervals on the outside of the core portion 101 provided in the shape of an end mill, but the cutter 120 is not limited to this and can be arranged at smaller angular intervals. do.

The cutter cooling channel 125 and the connection channel 130 are connected to the core cooling channel 105 at the center of the core portion 101, and follow the spiral shape of the cutter 120 on the outside of the core portion 101. It is placed.

The cutter cooling channel 125 and the connecting channel 130 are spirally arranged passages in which fine passages or thin slits are formed in the core cooling channel 105 toward the cutter 120 in correspondence with the shape of the cutter 120, and are used for cutting. The cooling fluid supplied at the time flows in the radial direction in the core portion 101 to cool the cutter 120.

The core cooling channel 105, the cutter cooling channel 125, and the connection channel 130 are connected structures and may be formed by metal stacking along the central axis direction of the core portion 101.

The core portion 101, the core cooling channel 105, the cutter 120, the cutter cooling channel 125, and the connection channel 130 are formed simultaneously by laminating metals used as tools through 3D printing.

The core cooling channel 105 has a straight structure and can be formed by drilling, but it is appropriate to form it together during metal stacking in 3D printing as described above in terms of saving later processing work.

The cutter cooling channel 125 provided in the cutter 120 is formed to have a cross-sectional structure corresponding to the shape of the cutter 120, and the formation of a complex fine passage in the shape of the cutter 120 is not possible without metal lamination. impossible.

The actual arrangement and cross-sectional structure of the cutter cooling channel 125 in the cutter 120 will be examined in detail.

The cutter 120 has a rake face 122 corresponding to the cutting surface and a flank face 123 corresponding to guiding the cutting chip.

The rake face 122 has a concave curved shape, and the flank face 123 has a bulging curved shape. The rake face 122 and the flank face 123 meet at the edge portion 121 where cutting is performed to create a cutting edge shape. .

The flank face 123 serves to discharge the cut chips to the outside of the cutting surface, and generates less frictional heat compared to the rake face 122.

In this way, the cutter 120 has a rake face 122 corresponding to the cutting surface and a flank face 123 corresponding to the guidance of the cutting chip, and the cutter cooling channel 125 has a rake face 122 more than the flank face 123. ) can be formed to provide more flow to the side.

The cutter cooling channel 125 is arranged so that more cooling fluid flow is supplied to the rake face 122 side than to the flank face 123, thereby smoothly cooling the rake face 122 side, where frictional heat is mainly generated during cutting. make it

In this way, having more cutter cooling channels 125 on the rake face 122 side than on the flank face 123 is advantageous in terms of protecting the tool from heat generated during cutting and preventing thermal deformation of the cutting surface.

The cutter cooling channel 125 includes a plurality of rake capillary channels 126 extending from the connection channel 130 toward the rake face 122, and a plurality of rake capillary channels 126 extending from the connection channel 130 toward the flank face 123. It may include a flank capillary channel (127).

Two or more rake capillary channels 126 may be disposed, and one or more flank capillary channels 127 may be disposed. For example, as shown in FIG. 2, three rake capillary channels 126 may be disposed, and three flank capillary channels 127 may be disposed.

Additionally, the rake capillary channel 126 may have a longer channel length than the flank capillary channel 127 and may have a wider channel width than the flank capillary channel 127 .

In this way, the rake capillary channel 126 is arranged longer and wider than the flank capillary channel 127, so that more cooling fluid is supplied to the rake face 122, where more cutting heat is generated than the flank face 123. You can.

In the cutter cooling channel 125, the rake capillary channel 126 is arranged so that more cooling flow is supplied to the rake face 122 side than to the flank face 123, so the rake face 122 where frictional heat is mainly generated during cutting. Makes side cooling smoother.

As the cutter cooling channel 125 supplies more cooling flow to the rake face 122 than to the flank face 123, it is advantageous in terms of protecting the tool from heat generated during cutting and preventing thermal deformation of the cutting surface. .

Meanwhile, the connection channel 130 is formed radially from the core cooling channel 105 toward the flank face 123, and the rake capillary channel 126 in the connection channel 130 is inclined toward the rake face 122. , the flank capillary channel 127 in the connection channel 130 may be disposed inclined toward the flank face 123.

The inclined arrangement of the rake capillary channel 126 and the flank capillary channel 127 in this connection channel 130 reduces the flow resistance of the cooling fluid and provides more cooling area than a horizontal structure for the connection channel 130. , so that cooling fluid can be sufficiently supplied to the edge portion 121.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as unitary may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the patent claims described below, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention.

100: Cutting tool 101: Core portion
105: core cooling channel 120: cutter
121: Edge part 122: Lake face
123: Flank face 125: Cutter cooling channel
126: Lake Moses Channel 127: Flank Moses Channel
130: connection channel

Claims (7)

core part;
a core cooling channel provided in the center of the core portion;
A cutter provided outside the core portion and having a rake face corresponding to a cutting surface and a flank face corresponding to guiding the cutting chip;
a cutter cooling channel provided in the cutter and extending to an outer surface of the cutter; and
It includes a connection channel connecting the core cooling channel and the cutter cooling channel,
The core cooling channel, the cutter cooling channel, and the connection channel are formed as the core portion and the cutter are formed by metal 3D printing,
The connection channel is formed radially from the core cooling channel toward the flank face,
The cutter cooling channel includes a plurality of rake capillary channels extending from the connection channel toward the rake face; and a plurality of flank capillary channels extending from the connection channel toward the flank face,
Each of the connection channel, race capillary channel, and flank capillary channel is formed by being disposed on a plane perpendicular to the longitudinal direction of the core portion,
The cooling fluid passing through the outer end of the connection channel, the cooling fluid passing through the race capillary channel, and the cooling fluid passing through the flank capillary channel are each sprayed in different directions,
A cutting tool having an internal cooling channel of a porous structure, wherein the cutter cooling channel is provided to provide a greater flow rate to the rake face side than to the flank face.
delete delete In claim 1,
In the connection channel, the rake capillary channel is inclined toward the rake face,
A cutting tool having an internal cooling channel of a porous structure, wherein the flank capillary channel in the connection channel is inclined toward the flank face.
In claim 1,
The rake capillary channels are arranged in two or more,
A cutting tool having an internal cooling flow path of a porous structure, characterized in that one or more flank capillary channels are arranged.
In claim 1,
A cutting tool having an internal cooling flow path of a porous structure, wherein the rake capillary channel has a wider channel width than the flank capillary channel.
In claim 1,
The cutter, cutter cooling channel, and connection channel are provided in a plurality of spiral shapes along the outer peripheral surface of the core portion,
A cutting tool having an internal cooling channel of a porous structure, wherein the core portion, the cutter, the cutter cooling channel, the connecting channel, and the core cooling channel are formed of metal laminates along the central axis direction of the core.

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