High-Durability 3-Flute End Mill

Abstract

The present invention relates to a high-durability 3-blade end mill for processing an IC chip mounting groove of a laminated card having a stainless steel (SUS) layer formed on the upper side and a plastic layer formed on the lower side, comprising: a body part made of a cemented carbide material containing 12% cobalt; a mega-chrome coating layer formed on the surface of the body part; and a cutting part formed extending in a spiral direction along the circumference of the body part.

Description

Technology Field

[0001] The present invention relates to a high-durability 3-blade end mill, and more specifically, to a high-durability 3-blade end mill for processing heterogeneous material laminated cards designed to precisely process the IC chip mounting groove of a laminated card combining a stainless steel layer and a plastic layer at high speed, while simultaneously improving tool life and automatically cleaning foreign substances after processing. Background Technology

[0003] Recently, IC cards used in the financial and security sectors are being manufactured in a laminated form combining plastic materials with metals such as stainless steel (SUS) to ensure both visual sophistication and physical strength. In the groove machining process for mounting IC chips on these heterogeneous laminated cards, a technical challenge arises in that the strong cutting resistance of the metal layer and the thermal deformation characteristics of the plastic layer must be overcome simultaneously. When using a standard end mill, the high heat and friction generated during the processing of the metal layer cause rapid wear on the cutting edge, leading to a shortened tool life and reduced machining precision. Furthermore, if micro-chips generated during plastic processing melt due to the cutting heat of the metal layer and become lodged between the end mill blades, chip evacuation is hindered, causing scratches on the machined surface or leading to tool breakage. Conventional machining methods have relied on manual removal of these foreign substances or the application of large amounts of coolant, but these approaches reduce process efficiency and result in environmental pollution and a decline in card quality. In particular, while two-flute end mills may be advantageous in terms of machining speed, they have limitations in precision machining due to the concentrated load per tooth, whereas four-flute structures are unsuitable for machining composite materials such as laminated cards due to the narrow chip evacuation space. Furthermore, cutting tool coating technology is tailored for machining high-hardness alloys, making it difficult to achieve optimal lubrication and wear resistance performance in environments where metals and plastics are mixed. Vibrations generated during the machining process are identified as one of the main factors that increase the defect rate of the final product by causing dimensional errors in the IC chip mounting groove. Therefore, there is an urgent need for the development of dedicated tools equipped with material compositions and geometric structures optimized for the characteristics of dissimilar materials. Problems with conventional technology include rapid tool wear due to the machining of high-hardness stainless steel, scratches on the machined surface caused by the adhesion of plastic chips, reduced precision due to heat and vibration generated during machining, and additional labor required to remove residual foreign substances after machining.

[0004] Meanwhile, the aforementioned background technology is technical information that the inventor possessed for the derivation of the present invention or acquired during the process of deriving the present invention, and it cannot necessarily be considered publicly known technology disclosed to the general public prior to the filing of the present invention. Prior art literature

[0006] Korean Registered Patent No. 10-1861953 (Published May 28, 2018) The problem to be solved

[0007] The present invention aims to provide a structure that optimizes the material and coating of a tool to withstand high heat and friction generated during the machining of a workpiece combined with a stainless steel (SUS) layer and a plastic layer, effectively disperses the cutting load to suppress vibration, and prevents scratches caused by chips generated during machining. Additionally, the technical objective is to maintain the cutting performance of the tool and maximize the efficiency of the production process by providing a unit capable of automatically cleaning foreign substances remaining between the spiral grooves of the tool after machining.

[0008] The technical problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0010] A high-durability 3-blade end mill according to one embodiment of the present invention comprises: a body portion made of a cemented carbide material containing 12% cobalt; a mega-chrome coating layer formed on the surface of the body portion; and a cutting portion formed extending in a spiral direction along the circumference of the body portion.

[0011] In one embodiment, the cutting part may be formed with a three-blade structure to prevent chips generated during processing from striking the processing surface and causing scratches.

[0012] In one embodiment, each blade of the cutting part forms a web angle of 4º to prevent bulging of the material when processing the plastic layer, and an R-GASH structure having a round cross-section may be formed at the end to suppress vibration and prevent breakage.

[0013] A high-durability 3-blade end mill according to another embodiment of the present invention may further include an end mill cleaning unit that separates and removes foreign matter attached to the cutting part after the cutting process is completed.

[0014] In one embodiment, the end mill cleaning unit may include: a module housing formed in a cylindrical shape; a rotatable inner sleeve formed in a cylindrical pipe shape so that the cutting part can be inserted along the inside and connected to be rotatable along the inner surface of the module housing; and a cleaning module installed at a constant interval along the inner surface of the rotatable inner sleeve, which separates and removes foreign matter by moving in a spiral direction along the gaps between each blade of the cutting part while rotating the rotatable inner sleeve as the cutting part is inserted into the inside of the rotatable inner sleeve.

[0015] In one embodiment, the cleaning module may include: a base mounting groove formed on the inner circumference of the rotating inner sleeve; a base plate mounted in the base mounting groove; a cushioning elastic body installed inside the base mounting groove to support the base plate and cushion vibrations and shocks transmitted from the base plate; two wheel supports installed upright on one side and the other side of the base plate, respectively; a wheel shaft connected to be rotatable between the two wheel supports; a rotating wheel installed by axial coupling to the wheel shaft and mounted in close contact with the side of the cutting edge of the cutting part to rotate; a cleaning pad installed covering the circumference of the rotating wheel and rotating together with the rotating wheel as it rotates to remove foreign matter attached to the side of the cutting edge of the cutting part; and two wheel driving force transmission units installed at each front end of the two wheel supports, mounted in close contact with the side of the cutting edge of the cutting part, and providing rotational driving force to the rotating wheel to rotate as the cutting part moves up and down along the inside of the rotating inner sleeve.

[0016] In one embodiment, the wheel driving force transmission unit may include: a first support installed on the upper side of the wheel support; a second support installed on the upper side of the wheel support so as to be inclined with respect to the first support; a third support installed so as to be inclined on the upper upward surface of the first support; a fourth support installed so as to be inclined on the upper upward surface of the second support, with its upper end connected to the upper end of the third support; a first driving wheel connected so as to be rotatable using the connecting shafts of the upper ends of the third support and the fourth support as rotational axes, seated in close contact with the side of the blade of the cutting unit, and rotating along the side of the blade of the cutting unit; and a second driving wheel connected to each of the first driving wheel and the rotating wheel by gear coupling, and transmitting the rotational driving force of the first driving wheel to the rotating wheel.

[0017] In one embodiment, the cleaning module may further include a cleaning brush installed along the side of the rotating wheel. Effects of the invention

[0019] The present invention provides the advantage of significantly extending the life of a tool by effectively withstanding the thermal load and friction generated during stainless steel processing through the application of a cemented carbide body containing 12% high cobalt content and a megachrome coating layer.

[0020] By forming the cutting section with a 3-blade structure, the cutting load per blade is distributed compared to 2 blades, and a wider chip evacuation space is secured compared to 4 blades, thereby preventing scratches on the machined surface and maintaining stable surface roughness even in high-speed machining environments.

[0021] Through the geometric design of the web angle and R-GASH structure, bulging occurring during plastic layer processing is suppressed, and vibration and cutting edge breakage are prevented, enabling precise machining of IC chip mounting grooves.

[0022] By mechanically and automatically removing foreign matter adhering to the tool after cutting through a separately provided cleaning unit, downtime caused by manual cleaning can be minimized and quality consistency in the continuous machining process can be ensured.

[0023] As a result, it demonstrates excellent economic effects by extending the tool replacement cycle and lowering the defect rate in the special processing of laminated cards combining dissimilar materials, thereby reducing overall production costs.

[0024] The effects of the present invention are not limited to those mentioned above, and various effects may be included within the scope obvious to a person skilled in the art from the contents described below. Brief explanation of the drawing

[0026] FIG. 1 is a diagram showing the schematic configuration of a high-durability 3-blade end mill according to one embodiment of the present invention. FIGS. 2 to 4 are drawings illustrating the cutting portion of FIG. 1. FIG. 5 is a diagram showing the schematic configuration of a high-durability 3-blade end mill according to another embodiment of the present invention. Figure 6 is a drawing showing the cleaning module of Figure 5. Figure 7 is a drawing showing the wheel driving force transmission unit of Figure 6. Specific details for implementing the invention

[0027] The following detailed description of the invention refers to the accompanying drawings, which illustrate specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that various embodiments of the invention are different but need not be mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in relation to one embodiment. It should also be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. Accordingly, the following detailed description is not intended to be limiting, and the scope of the invention is limited only by the appended claims, including all equivalents to those claimed therein, provided they are appropriately described. Similar reference numerals in the drawings refer to the same or similar functions across various aspects.

[0028] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

[0029] FIG. 1 is a diagram showing the schematic configuration of a high-durability 3-blade end mill according to one embodiment of the present invention.

[0030] Referring to FIG. 1, a high-durability 3-blade end mill (10) according to one embodiment of the present invention includes a body portion (100), a megachrome coating layer (200), and a cutting portion (300).

[0031] The body part (100) is formed of a cemented carbide material and performs the role of maintaining the basic framework of the entire tool and ensuring rigidity during high-speed rotation.

[0032] The body part (100) adopts a cemented carbide material containing 12% cobalt content, thereby providing high heat resistance characteristics in which hardness is not reduced even in a high-temperature environment generated during processing of stainless steel (SUS) material.

[0033] A material with a cobalt content controlled at 12% prevents deformation of the tool and maximizes wear resistance under processing conditions where it simultaneously penetrates the lower plastic layer and the upper metal layer of a laminated card, thereby significantly extending the tool replacement cycle.

[0034] The megachrome coating layer (200) is deposited on the surface of the body part (100) and serves the function of protecting the tool from external friction and controlling surface activity.

[0035] The megachrome coating layer (200) has very high surface hardness to block frictional heat generated during metal processing and has a smooth surface finish to prevent the sticking phenomenon where chips stick to the blade.

[0036] The megachrome coating layer (200) helps to reduce the machining load and maintain the surface roughness of the workpiece card precisely by achieving significantly lower cutting resistance compared to other coating materials.

[0037] The cutting portion (300) refers to a blade portion that is wound spirally along the outer surface of the body portion (100) and substantially cuts and removes the workpiece.

[0038] The cutting portion (300) forms a continuous spiral trajectory along the circumference of the body portion (100) to induce the cutting force to be dispersed rather than concentrated at a specific point, thereby increasing processing stability.

[0039] A high-durability 3-blade end mill (10) according to one embodiment of the present invention having the configuration described above provides the effect of being able to precisely process the IC chip mounting groove of a laminated card with different materials laminated thereon at high speed by combining the durability of a high-content cobalt material and the low-friction characteristics of a megachrome coating.

[0041] In one embodiment, the cutting portion (300) includes a three-blade structure (310-1, 310-2, 310-3) as shown in FIG. 2.

[0042] The 3-blade structure (310-1, 310-2, 310-3) is designed so that three cutting blades are arranged at equal intervals on the same circumference to offset vibrations generated during the cutting process and to exert balanced machining force. According to the research results, in the case of the existing 2-blade (2F) tool, the cutting load applied to one blade reached about 50%, which had a high risk of breakage, but it was confirmed that by changing it to a 3-blade structure, the load per blade could be distributed to about 30% to 35%.

[0043] This load distribution creates synergy with the 12% high-cobalt body and the megachrome coating layer, effectively overcoming the strong resistance during stainless steel layer processing and preventing tool breakage. In addition, the 3-blade structure prevents chips generated during processing from getting stuck between the tool and the workpiece and striking the machined surface, thereby fundamentally blocking defects such as unwanted scratches on the laminated card surface and ensuring stable surface roughness.

[0044] The cutting unit (300) having the configuration described above achieves excellent stability by distributing the cutting load through an optimized number of cutting edges and maintaining consistent machining quality.

[0046] Referring to FIGS. 3 and 4, each blade of the cutting section (300) includes a web angle (320) and an R-GASH structure (330).

[0047] The web angle (320) was precisely machined by increasing it from the existing 2 degrees to 4 degrees. This is to optimize the internal volume of the chip evacuation space (flute), which may become narrow due to the adoption of a 3-blade structure.

[0048] In particular, the 4-degree web angle (320) effectively suppresses the bulging phenomenon where the material expands or is pushed upward due to heat generated during plastic layer processing. In addition, by rapidly discharging the generated chips to the outside, it prevents heat accumulation in the processing area, thereby extending tool life and improving processing quality. Furthermore, to alleviate cutting resistance, a helix angle of approximately 30 degrees is applied to disperse cutting impact and maximize chip evacuation efficiency.

[0049] The R-GASH structure (330) is given a round curved cross-section at the tip of the cutting edge, which is an improvement over the existing straight barbed structure.

[0050] To prevent stress concentration at the corners and the resulting fine chipping that is prone to occur in straight structures, the R-GASH structure (330) effectively distributes the load applied to the cutting edge. Experiments confirmed that when the R-Gash type is applied, noise and vibration generated during machining are significantly reduced and the tool life is stabilized, which plays a key role in maintaining the surface finish of the workpiece precisely even under conditions of high-speed rotation of 20,000 RPM and a feed speed of 700 mm / min.

[0052] FIG. 5 is a diagram showing the schematic configuration of a high-durability 3-blade end mill according to another embodiment of the present invention.

[0053] Referring to FIG. 5, a high-durability 3-blade end mill (20) according to another embodiment of the present invention includes a body part (100), a megachrome coating layer (200), a cutting part (300), and an end mill cleaning unit (400).

[0054] Here, the body part (100), the megachrome coating layer (200), and the cutting part (300) are identical to the components of FIG. 1, so the description thereof will be omitted to avoid duplication of description.

[0055] The end mill cleaning unit (400) is a device that mechanically removes fine chips and foreign matter remaining on the tool after the cutting operation is completed.

[0056] The end mill cleaning unit (400) separates foreign matter stuck between the spiral grooves of the cutting part (300) to maintain the cutting force of the tool in its initial state and prevents machining errors from occurring.

[0057] A high-durability 3-blade end mill (20) according to another embodiment of the present invention having the configuration described above manages the cleanliness of the tool in an automated manner, thereby reducing the risk associated with manual cleaning and maximizing production efficiency.

[0059] Referring to FIG. 5, the end mill cleaning unit (400) includes a module housing (410), a rotating inner sleeve (420), and a cleaning module (430).

[0060] The module housing (410) is a hollow cylindrical structure that forms the outer shell of the entire device and protects the internal drive components from external impact.

[0061] The rotating inner sleeve (420) is installed to rotate smoothly along the inner surface of the module housing (410) and provides a guide path into which an end mill is inserted.

[0062] The cleaning module (430) rotates together with the rotating inner sleeve (420) and moves flexibly along the spiral blade trajectory of the end mill to perform close cleaning.

[0063] The end mill cleaning unit (400) having the configuration described above performs the function of effectively cleaning a complex spiral structure through a rotation mechanism corresponding to the lifting and lowering movement of the end mill.

[0065] Figure 6 is a drawing showing the cleaning module of Figure 5.

[0066] Referring to FIG. 6, the cleaning module (430) includes a base mounting groove (431), a base plate (432), a cushioning elastic body (433), a wheel support (434), a wheel shaft (435), a rotating wheel (436), a cleaning pad (437), and a wheel driving force transmission unit (438).

[0067] The base mounting groove (431) is formed concavely on the inner wall of the rotating inner sleeve (420) to provide a mounting space in which the cleaning module can be fixed without movement.

[0068] The base plate (432) is coupled to the base mounting groove (431) and serves as a support plane that stably supports the driving components located on the upper side.

[0069] The cushioning elastic body (433) is installed on the back surface of the base plate (432) to regulate the contact pressure between the end mill and the cleaning device and to absorb sudden shocks, thereby preventing damage to the parts.

[0070] The wheel support (434) protrudes vertically from the base plate (432) and forms a mechanical frame that allows the rotating wheel (436) to rotate stably.

[0071] The wheel shaft (435) is installed through the wheel support (434) and serves as the central axis of rotation of the rotating wheel (436), ensuring smooth rolling motion.

[0072] The rotating wheel (436) is a dynamic cleaning means that rotates in direct contact with the side of the end mill blade and pushes out foreign matter.

[0073] The cleaning pad (437) is made of a flexible material that wraps around the outer circumference of the rotating wheel (436) and adheres to the blade surface, thereby performing a fine cleaning function that adsorbs and removes even fine dust.

[0074] The wheel driving force transmission unit (438) is a power conversion unit that converts mechanical energy generated during the downward movement of the end mill into rotational torque and forcibly drives the rotating wheel (436).

[0075] The cleaning module (430) having the configuration described above combines elastic restoring force and forced rotational force to ensure uniform cleaning quality regardless of the geometric shape of the blade.

[0077] A cleaning module (430) having the configuration described above may further include a cleaning brush (439).

[0078] Here, the base mounting groove (431), base plate (432), cushioning elastic body (433), wheel support (434), wheel shaft (435), rotating wheel (436), cleaning pad (437), and wheel driving force transmission part (438) are identical to the components of FIG. 6, so their descriptions are omitted to avoid duplication of descriptions.

[0079] The cleaning brush (439) is an auxiliary cleaning means that is attached to the side of the rotating wheel (436) to remove foreign matter from the deep valleys between the blades that are not physically touched by the cleaning pad (437).

[0080] The cleaning brush (439) performs the function of effectively separating and removing metal chips embedded in the micro-holes or grooves of the cutting edge surface through a number of flexible brush bristles.

[0081] The cleaning module (430) having the configuration described above achieves the effect of keeping all parts of the tool clean by minimizing blind spots in cleaning through a combination of pad-type adsorption cleaning and brush-type physical impact cleaning.

[0083] Figure 7 is a drawing showing the wheel driving force transmission unit of Figure 6.

[0084] Referring to FIG. 7, the wheel driving force transmission unit (438) includes a first support (4381), a second support (4382), a third support (4383), a fourth support (4384), a first driving wheel (4385), and a second driving wheel (4386).

[0085] The first support (4381) extends from the top of the main wheel support (434) and serves as a base arm that determines the position of the drive gears.

[0086] The second support member (4382) is positioned to form a certain angle with the first support member (4381) to reinforce the support structure against external pressure.

[0087] The third support (4383) and the fourth support (4384) form a link structure with their ends connected to each other to control and support the rotation radius of the first drive wheel (4385).

[0088] The first drive wheel (4385) is a primary power collector that converts the linear motion of the end mill into rotational motion while rolling along the side trajectory of the end mill's blade.

[0089] The second drive wheel (4386) rotates in engagement with the first drive wheel (4385) and performs a gear shifting function by amplifying and transmitting the collected rotational force to the final washing wheel, the rotating wheel (436).

[0090] The wheel driving force transmission unit (438) having the configuration described above provides the effect of reliably driving the cleaning part by responding sensitively to even the minute movement of the end mill through a precise gear train.

[0092] The embodiments described above are for illustrative purposes only, and those skilled in the art will understand that the embodiments described above can be easily modified into other specific forms without altering the technical concept or essential features of the embodiments described above. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0094] The scope of protection sought through this specification is defined by the claims set forth below rather than by the detailed description above, and should be interpreted to include all modifications or variations derived from the meaning and scope of the claims and the concept of equivalents. Explanation of the symbols

[0096] 10, 20: High-durability 3-flute end mill 100: Body part 200: Megachrome coating layer 300: Cutting part 400: End mill cleaning unit

Claims

Claim 1 A high-durability 3-blade end mill for machining an IC chip mounting groove of a laminated card having a stainless steel (SUS) layer formed on the upper side and a plastic layer formed on the lower side, comprising: a body part made of a cemented carbide material containing 12% cobalt; a Mega-Chrome coating layer formed on the surface of the body part; and a cutting part formed extending in a spiral direction along the circumference of the body part; wherein the cutting part is formed with a 3-blade structure to prevent chips generated during machining from striking the machining surface and causing scratches, and each blade of the cutting part forms a web angle of 4º to prevent bulging of the material when machining the plastic layer, and an R-GASH structure having a round cross-section is formed at the end to suppress vibration and prevent breakage. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete

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