Method for manufacturing kitchen knife

Abstract

To provide a method for manufacturing a kitchen knife capable of simplifying a manufacturing process and suppressing occurrence of excess material and occurrence of dust.SOLUTION: A 3D print fabrication step is performed for performing fabrication of the entirety of a kitchen knife 1 with a 3D printer 100, the kitchen knife having: a blade portion 10 which includes a cutting edge portion 11 that includes an edge 13 and a back portion 12 that is positioned on an opposite side of the edge 13 in the cutting edge portion 11, and in which thickness of the cutting edge portion 11 gradually decreases from the back portion 12 side toward the edge 13; and a handle portion 20 which is connected to the blade portion 10.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a method of manufacturing a kitchen knife. [Background technology]

[0002] A kitchen knife has a structure in which a ferrule and a handle are attached to a metal blade including the cutting edge (for example, see Patent Document 1). Conventionally, kitchen knives are manufactured by laser processing or pressing a flat metal plate, hardening it in a heat treatment process, shaping the blade through various processes such as grinding and polishing, welding the ferrule, and then assembling the handle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-042088 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional knife manufacturing methods require many steps to form the blade, as well as many other manufacturing steps such as a step to connect a ferrule to the blade, a step to attach a handle, etc. In addition, because the blade is formed from a metal plate, surplus material is generated that is not used for the blade, and a lot of dust is generated during the grinding and polishing process to form the shape of the blade tip.

[0005] An object of the present disclosure is to provide a method for manufacturing a knife that can simplify the manufacturing process while suppressing the generation of excess material and dust. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the manufacturing method of the knife described in claim 1 includes a 3D printing process in which the entire knife (1) having a blade portion (10) including a cutting edge (11) including a cutting edge (13) and a back portion (12) located on the opposite side of the cutting edge of the cutting edge, in which the thickness of the cutting edge gradually decreases from the back portion side toward the cutting edge, and a handle portion (20) connected to the blade portion is shaped by a 3D printer (100).

[0007] In this way, by using a 3D printer to form the entire knife having a blade and handle with a tapered cutting edge from the beginning, the manufacturing process can be reduced and simplified compared to the conventional method of assembling each part after forming them into the desired shape. In addition, it is almost unnecessary to process the blade and handle into the desired shape, and the surplus material generated during the processing can be eliminated, and more material than necessary is not used, which makes it possible to reduce material. Furthermore, if the blade is formed so that the cutting edge is tapered from the beginning, it is possible to suppress the generation of dust.

[0008] In the invention described in claim 2, in the 3D printing process, in addition to the handle portion (21), a handle base (22) that connects the blade portion and the handle portion and gradually increases in dimension from the thickness of the blade portion to the thickness of the handle portion from the blade portion to the handle portion is formed together with the blade portion as part of the handle.

[0009] By using a 3D printer to create a knife, it is possible to create a knife with a structure that has never been seen before, so when forming the blade and handle, a structure in which the handle and the blade are connected via the base of the handle can be created at the same time. In addition, by making the base of the handle so that the dimensions gradually increase from the thickness of the thin blade to the thickness of the handle from the blade to the handle, it is possible to create a structure that is continuously connected from the blade to the handle.

[0010] In the invention described in claim 3, in the 3D printing process, a 3D printer is used to form a knife by stacking multiple layers into the shape of a knife, and the knife is formed by stacking layers from the back of the knife toward the tip of the knife so that the back of the knife faces downward and the tip of the knife faces upward.

[0011] The blade gradually becomes thinner from the back to the tip. When forming a knife with this shape, it is easier to form the thick back first and then the thin tip, rather than forming the thin tip first and then the thick back.

[0012] In the invention described in claim 4, in the 3D printing process, a knife is formed by stacking multiple layers into the shape of a knife using a 3D printer, and the knife is formed so that one of the two surfaces of the blade portion of the knife faces upward and the other faces downward.

[0013] In this way, by determining the top and bottom orientation of the blade and molding it, when forming a knife with a multi-layered structure using a 3D printer, the blade can be aligned along the surface direction of the layers, that is, the cutting direction of the knife can be aligned along the surface direction of each layer. This makes it possible to make the blade stronger.

[0014] In the invention described in claim 5, a blade sharpening process is included after the 3D printing process to sharpen the cutting edge including the blade tip. Since the tapered blade and handle are all already formed by the 3D printer, a knife with a sharp blade tip can be completed by proceeding to at least the blade sharpening process after the 3D printing process, simplifying the manufacturing process.

[0015] The invention described in claim 6 includes a heat treatment process for hardening the knife after the 3D printing process, a distortion relief process for removing distortion from the knife that has been heat treated, and a sharpening process for sharpening the cutting edge including the cutting edge of the knife that has been subjected to the distortion relief process. In this way, even if the heat treatment process and the distortion relief process are performed in addition to the sharpening process, it is possible to omit the steps that were previously required, and the manufacturing process is simplified. In addition, as in the invention described in claim 7, even if a shot blasting process is performed on the knife that has been subjected to the distortion relief process to roughen the surface of the cutting edge in the blade at a location other than the cutting edge, it is possible to omit the steps that were previously required, and the manufacturing process is simplified.

[0016] In the invention described in claim 8, in the 3D printing molding process, a protruding rib (16) is formed on one side of the blade portion, and the knife is molded so that the position on the other side (10b) opposite the one side (10a) of the blade portion corresponding to the position where the rib is formed on the one side and the position corresponding to the periphery of the position where the rib is formed are flush with each other.

[0017] In this way, by using a 3D printer, even if a rib is formed on one side of the blade, the position of the rib on the other side and the corresponding position around it can be shaped so that they are flush with each other. In addition, because a shape can be created without dents caused by the formation of the rib, there is no need to carry out a grinding process to flatten the other side, which makes it possible to further simplify the manufacturing process.

[0018] In the invention described in claim 9, in the 3D printing process, a three-dimensional structure is formed having a cavity (30) that is recessed or penetrates the surface of the knife in at least one of a location of the blade portion other than the cutting edge of the cutting edge and the handle portion.

[0019] In this way, a 3D printer can be used to create knives with complex structures, such as three-dimensional structures with cavities. In this case, by providing cavities in the knife, it is possible to reduce the amount of material used. Also, by providing cavities in a location other than the cutting edge of the blade or in the handle, it is possible to reduce material in the parts that are not used as a blade, which makes it possible to avoid using more material than necessary and to appropriately design the weight of the knife.

[0020] Note that the reference symbols in parentheses attached to each component indicate an example of the correspondence between the component and specific components described in the embodiments described below. [Brief description of the drawings]

[0021] [Figure 1] 1A and 1B are diagrams showing a kitchen knife according to a first embodiment of the present disclosure, in which (a) is a front view, (b) is a view of (a) seen from above, and (c) is a view of (a) seen from the left side. [Diagram 2] 1 is a flowchart showing a manufacturing process of a knife. [Diagram 3] This is a diagram showing how a knife is manufactured using a 3D printer. [Figure 4A] FIG. 2 is an enlarged cross-sectional view of the cutting edge portion near the cutting edge after the 3D printing process. [Figure 4B] FIG. 4 is an enlarged cross-sectional view of a cutting edge portion of a cutting edge portion after a sharpening process. [Diagram 5] 11 is a cross-sectional view of a cutting blade portion of a knife according to a second embodiment of the present disclosure. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following, including other embodiments described below, the same reference numerals will be used to denote the same or equivalent parts in each embodiment.

[0023] (First embodiment) In this embodiment, a method for manufacturing a knife using a 3D printer will be described. The drawings attached to this specification show the X-axis, Y-axis, and Z-axis. The length direction of the knife is called the X-axis, the blade width direction perpendicular to the X-axis is called the Y-axis, and the thickness direction of the knife perpendicular to the X-axis and Y-axis is called the Z-axis.

[0024] [Knife structure] First, referring to FIG. 1, a knife 1 manufactured using a 3D printer will be described. The knife 1 shown in FIG. 1 includes a blade 10 and a handle 20, and is structured such that the handle 20 is connected to the blade 10 in the X-axis direction. The blade 10 and the handle 20 are made of, for example, maraging steel, and are all formed simultaneously as one part using a 3D printer. The material of the blade 10 and the handle 20 may be other metals such as stainless steel and titanium, or other materials such as ceramics and resin.

[0025] The blade portion 10 has a cutting edge portion 11 and a back portion 12, and is connected to a handle portion 20 at the back portion 12.

[0026] The cutting edge portion 11 is a portion extending from the cutting edge 13 to the sinew 14. The cutting edge portion 11 is formed in a thin plate shape, and the cross section along the YZ plane from the sinew 14 toward the cutting edge 13 gradually tapers, and one surface 10a and the other surface 10b on the opposite side are flat surfaces inclined with respect to the Y-axis direction, or curved surfaces whose cross section in a plane parallel to the YZ plane is bulging like a clam. The cutting edge portion 11 is sharp all over the cutting edge 13 from the cutting edge 13a to the middle 13b and jaw 13c.

[0027] In addition, the back portion 12 has a three-dimensional shape from the ridge 14 to the ridge 15, and has a three-dimensional structure that is continuously connected to the handle portion 20. The dimension of the back portion 12 in the Y-axis direction gradually increases from the tip side of the blade portion 10 in the X-axis direction to the rear end side, specifically from the position between the cutting edge 13a and the middle part 13b of the cutting edge portion 11 toward the jaw 13c, and at the position where it connects to the handle portion 20, it matches the dimension of the handle portion 20 in the Y-axis direction.

[0028] The handle 20 includes a handle 21, a handle base 22, and a handle end 23, and is arranged on the opposite side of the blade 10 of the knife 1, and is rod-shaped. The handle 21 is a part that is held by a user, and is shaped to be easy to hold, for example, a polygonal shape or an elliptical shape with rounded corners in cross section. The handle base 22 is a part that connects the handle 21 and the blade 10, and is shaped so that the thickness gradually increases from the thickness of the back 12 of the thin blade 10 to the thickness of the handle 21 from the blade 10 to the handle 21. Specifically, when the knife 1 is viewed from the ridge 15 side as shown in FIG. 1(b), the handle base 22 is shaped like an isosceles trapezoid with the tip of the knife 1 as the upper base and the rear end as the lower base. The handle base 22 may have a structure in which the thickness increases linearly from the back portion 12 to the handle portion 21, or the thickness increases from the back portion 12 to the handle portion 21, or the thickness may increase from a midway position from the back portion 12 to the handle portion 21. The handle butt 23 is the rear end of the handle portion 20.

[0029] In addition, a plurality of cavities 30 are formed by recessing or penetrating the surface in a portion of the knife 1 different from the cutting edge 13, preferably a portion different from the cutting edge 11, to form a three-dimensional structure. Specifically, the entire handle 20 including the back 12, the handle 21, and the handle base 22 has a three-dimensional structure having a cavity 30, and a cavity 30 is also formed in the handle butt 23 as shown in FIG. 1(c). This three-dimensional structure is a structure in which the back 12, the handle base 22, and the handle 21 are continuously connected, for example, as shown in FIG. 1(a) and (b). In other words, the blade 10 and the handle 20 are formed as an integral part, and the back 12 and the handle 20 are formed in a seamless three-dimensional structure up to the boundary position between the blade 10 and the handle 20. The knife 1 is formed in this structure.

[0030] [Knife manufacturing method] Next, a method for manufacturing the knife 1 configured as above will be described with reference to the flowchart shown in Fig. 2. The knife 1 is manufactured by carrying out each of the manufacturing processes from steps S1 to S7 shown in Fig. 2.

[0031] (a) 3D printing process First, in step S1, a 3D printing process is performed to form the kitchen knife 1 shown in FIG. 1 using a 3D printer. Any type of 3D printer may be used, but here, an example will be described in which the kitchen knife 1 is formed by additive manufacturing. FIG. 3 shows a 3D printer 100 used to form the kitchen knife 1. The 3D printer 100 is equipped with a printing machine 101, a control device 102, and the like. The printing machine 101 is a device that forms the kitchen knife 1 by additive manufacturing. The control device 102 outputs data used to manufacture the kitchen knife 1 to the printing machine 101 and controls the printing machine 101 to form the kitchen knife 1. The control device 102 is configured by a microcomputer equipped with a CPU, ROM, RAM, I / O, and the like, and stores various programs such as slicing software.

[0032] For example, the knife 1 is designed in advance using 3D CAD or the like, and the 3D data of the knife 1 is input into the control device 102. At this time, if the 3D data is 3D CAD data that is not polygon data, it is converted into polygon data by the control device 102. Next, the control device 102 uses slicing software to create slice data that indicates a molding pattern when the knife 1 is sliced ​​into each layer from the polygon data.

[0033] Then, the slice data is output from the control device 102 to the printer 101, and the modeling patterns for each layer are stacked in order based on the slice data to form the knife 1. For example, maraging steel is used as the material used for the modeling, but other metals such as stainless steel and titanium, and other materials such as ceramics and resins may also be used. As a result, the blade 10 and the handle 20 are formed simultaneously, the back 12 is connected to the handle 21 via the handle base 22, and the knife 1 in which the blade 10 and the handle 20 are integrated as a single component can be formed.

[0034] At this time, the order in which knife 1 is shaped from which point is arbitrary, but it is preferable to shape knife 1 by stacking each layer from back 12 to cutting edge 13, with back 12 facing downward and cutting edge 13 facing upward, as shown in Figure 3.

[0035] In the blade 10, the thickness gradually decreases from the back 12 side to the blade tip 13 side. When forming the blade 10 and the handle 20 using the 3D printer 100, it is easier to form the blade 10 by forming the thick back 12 first and then forming the thin blade tip 13 later, rather than forming the thin blade tip 13 first and then forming the thick back 12 later. In addition, it is desirable to make the thickness of the blade tip 13 as small as possible, for example, to about 0.2 mm as shown in FIG. 4A, in order to reduce the amount of processing during the blade setting process performed in the later process. However, if the blade tip 13 is formed last, it is not necessary to consider stacking something on the blade tip 13, so the thickness of the blade tip 13 can be made thinner.

[0036] (b) Heat treatment process The knife 1 produced in the 3D printing process is subjected to a heat treatment process for age hardening in step S2. In the heat treatment process, the knife 1 is subjected to high-temperature heat treatment and then cooled to room temperature, which promotes the time transformation of the structure of the material that constitutes the knife 1 and hardens the knife 1. In addition, by cooling and reheating as necessary, the knife 1 can be given a uniform hardness and further toughness that can suppress bending cracks.

[0037] (c) Strain removal process After the heat treatment process, a straightening process is performed as step S3. Since the knife 1 has distortion due to volume expansion and contraction, the straightening process involves straightening the distorted parts.

[0038] (d) Shot blasting process After the distortion removal process, a shot blasting process is performed as step S4. In the shot blasting process, glass beads made of fine glass particles are blasted onto the surface of the knife 1 in areas other than the cutting edge 13. This makes the surfaces of the blade 10 and handle 20 beautifully and finely roughened.

[0039] (e) Marking process After the shot blasting process, a marking process is performed as step S5. In the marking process, various markings such as the brand name, the history of materials used, and the date and time of each process are performed are performed on a certain part of the knife 1, such as the back 12. This allows for traceability.

[0040] (f) Blade sharpening process After the marking process, a blade-sharpening process is performed as step S6. In the blade-sharpening process, the cutting edge 11 of the blade 10 is sharpened. For example, when sharpening by wet sharpening, the blade is sharpened while water is poured on a whetstone (not shown) or the blade 10 so as not to generate heat due to friction. This makes the cutting edge 13 smoother and improves the sharpness. The blade 10 formed in the 3D printing process already has a tapered cutting edge 13 as shown in FIG. 4A. Therefore, the sharpening process here is different from grinding and polishing a flat plate with a rectangular cross section until the tip has a sharp cutting edge shape, and only requires a finishing sharpening process in which slight polishing is performed until the cutting edge 13 is sharp as shown in FIG. 4B. This also reduces the generation of dust.

[0041] (g) Packaging process Finally, in step S7, a packaging process is carried out in which the knife 1 that has passed the predetermined inspection is packed into a box. This completes the process of packaging the knife 1 and making it ready for shipment.

[0042] As described above, the knife 1 is formed by performing the 3D printing process using a 3D printer. As a result, the following effects are obtained.

[0043] (1) In the manufacturing method of the knife 1 described in this embodiment, the entire knife 1 is formed using a 3D printer 100. Conventionally, when the blade, handle, and ferrule are separately manufactured and then assembled into the desired shape, each process is required, and the number of manufacturing processes increases. However, by using the 3D printer 100 as in this embodiment, the entire knife 1 having the blade 10 and handle 20 with the blade tip 13 tapered from the beginning can be formed, so that the number of manufacturing processes can be reduced. In addition, by reducing the manufacturing process, it is possible to reduce the environmental load and energy consumption.

[0044] Specifically, in this embodiment, the knife 1 is manufactured by performing each of the steps S1 to S7 described above. Since the knife 1 can be manufactured by simply performing each of the steps S1 to S7, it is possible to simplify the manufacturing process of the knife 1 compared to the conventional method. In addition, among the steps S1 to S7, some steps can be omitted if the only focus is on completing the manufacturing of the knife 1, and the process can be further simplified. For example, the manufacturing of the knife 1 can be completed without performing the marking step S5 or the packaging step S7. In addition, if the knife 1 can be made closer to the shape of the final product when the knife 1 is shaped by the 3D printer 100, the heat treatment step, distortion relief step, and shot blasting step S2 to S4 can also be omitted. In other words, since the blade portion 10 with the tapered cutting edge 13 and the handle portion 20 have already been formed by the 3D printer 100, the knife 1 can be completed by at least proceeding to the sharpening process to sharpen the cutting edge 13, further simplifying the manufacturing process. Even if the heat treatment process, distortion relief process, and shot blasting process are performed in addition to the sharpening process, it is possible to omit steps that were previously necessary, thus simplifying the manufacturing process.

[0045] For example, in the conventional manufacturing method, a flat metal plate is laser-processed or pressed to form the outer shape of the blade, followed by a heat treatment process and a distortion removal process, followed by an outer peripheral grinding process and a skiving process to sharpen the tip of the flat blade. In addition, a blade leveling process is carried out to make the cutting edge a smooth, bulging, clam-shaped curved surface, and a glazing process is carried out to finely grind the entire blade. Then, a ferrule welding process is carried out to weld the ferrule and grind the welded part, and a handle is attached to the blade to which the ferrule is welded.

[0046] In contrast, according to the manufacturing method of this embodiment, the knife 1 in which the blade portion 10 and the handle portion 20 are connected and the blade tip 13 is tapered from the beginning can be formed by the 3D printer 100. This makes it possible to omit the laser processing or press processing, the outer circumference polishing process, the gap grinding process, the blade leveling process, the glazing process, the ferrule welding process, and the assembly process.

[0047] (2) The knife 1 can be formed in various shapes using the 3D printer 100, and the blade 10 and handle 20 can be formed with the cutting edge 13 tapered from the beginning. This makes it almost unnecessary to process the blade 10 and handle 20 into the desired shape, and eliminates the excess material generated when performing various processes, and does not require the use of more material than necessary, making it possible to reduce the amount of material used. In addition, as in the conventional manufacturing method, when a flat plate material is pressed or laser processed to form the outer shape of the blade, and then the plate material is ground to form the cutting edge shape, it is necessary to perform grinding and polishing processes to make the cutting edge sharp, which generates a lot of dust. In contrast, if the blade 10 is formed with the 3D printer 100 so that the cutting edge 13 is tapered from the beginning, the generation of dust can be significantly reduced.

[0048] (3) By using the 3D printer 100 to form the knife 1, it is possible to form the knife 1 with a structure that has not been seen before, and the knife 1 can be formed from a variety of materials, including not only metal but also ceramics and resin, thereby improving the freedom of knife design.

[0049] For example, when forming the knife 1 using the 3D printer 100, when forming the blade 10 and the handle 20, it is possible to simultaneously form a structure in which the handle 21 and the blade 10 are connected via the handle base 22. Then, by making the handle base 22 such that the dimension gradually increases from the thickness of the thin plate-like blade 10 to the thickness of the handle 21 from the blade 10 to the handle 21, it is possible to form a structure that is continuously connected from the blade 10 to the handle 21.

[0050] Also, it is possible to form a knife 1 with a complex structure, such as a three-dimensional structure having a cavity 30. In this case, by providing the cavity 30 in the knife 1, it is also possible to reduce the material of the knife 1. If the cavity 30 is formed in a location of the knife 1 other than the blade tip 13, preferably other than the cutting edge portion 11, such as the back portion 12 or the handle portion 20, it is possible to reduce the material in the portion not used as the blade, making it possible to avoid using more material than necessary, and also to appropriately design the weight of the knife 1.

[0051] (4) The blade 10 gradually becomes thinner from the back 12 side to the cutting edge 13 side. When forming a knife 1 having such a shape, if the thick back 12 is formed first and the thin cutting edge 13 is formed later, the shaping can be performed more easily than if the thin cutting edge 13 is formed first and the thick back 12 is formed later. Also, if the cutting edge 13 is formed last, there is no need to consider stacking anything on top of the cutting edge 13, so the thickness of the cutting edge 13 can be made thinner.

[0052] Second embodiment The second embodiment will be described. This embodiment is the same as the first embodiment except that the shape of the blade portion 10 is changed, and therefore only the parts that are different from the first embodiment will be described.

[0053] 5 shows the knife 1 after the 3D printing process of step S1 described in the first embodiment, cut in a cross section parallel to the YZ plane. As shown in this figure, a protruding rib 16 is formed on one surface 10a of the cutting edge portion 11 of the blade portion 10. On the other surface 10b opposite to the one surface 10a on which the rib 16 is formed, a position corresponding to the position where the rib 16 is formed on the one surface 10a and a position corresponding to the periphery of the position where the rib 16 is formed are flush with each other.

[0054] If the knife 1 is provided with the rib 16 on the one surface 10a side, the pieces of the food cut by the knife 1 are easily separated from the knife 1, and the knife 1 can be easily released from the blade. If the 3D printer 100 is used to manufacture the knife 1 equipped with such a rib 16, the knife 1 can be shaped so that the position of the rib 16 on the other surface 10b side and the corresponding position around it are flush with each other, even if the rib 16 is formed on the one surface 10a side of the blade part 10. When the rib 16 is formed by pressing or the like, a recess is formed on the other surface 10b side due to the formation of the rib 16, and therefore a process of grinding the thickness of the rib 16 to a thickness greater than the recess due to the formation of the rib is required to flatten the other surface 10b side. However, if the rib 16 is formed from the beginning by the 3D printer 100, a modeling can be performed without a recess due to the formation of the rib 16, and therefore the manufacturing process can be simplified.

[0055] (Other embodiments) The present disclosure is not limited to the above-described embodiments, and can be appropriately modified within the scope of the claims. In addition, in each of the above-described embodiments, it goes without saying that the elements constituting the embodiments are not necessarily essential, except when they are specifically stated as essential or when they are clearly considered essential in principle. In addition, in each of the above-described embodiments, when the numbers, values, amounts, ranges, etc. of the components of the embodiments are mentioned, they are not limited to the specific numbers, except when they are specifically stated as essential or when they are clearly limited to a specific number in principle. In addition, in each of the above-described embodiments, when the shapes, positional relationships, etc. of the components are mentioned, they are not limited to the shapes, positional relationships, etc., except when they are specifically stated or when they are limited to a specific shape, positional relationship, etc. in principle.

[0056] For example, in the first embodiment, the knife 1 is shaped in the 3D printing process so that the back portion 12 faces downward and the cutting edge 13 faces upward. However, this is just one example, and the knife 1 may be shaped in another direction. As one example, the knife 1 may be shaped so that one of the two surfaces of the blade portion 10 of the knife 1 faces upward and the other faces downward.

[0057] In this way, by determining the up-down direction of the blade portion 10 and molding it, when forming the knife 1 with a laminated structure of multiple layers using the 3D printer 100, the blade portion 10 can be aligned along the surface direction of the layers, that is, the cutting direction by the knife 1 can be aligned along the surface direction of each layer. When forming a laminated structure of multiple layers using the 3D printer 100, although the bonding between each layer is strong, it is possible to make the blade portion 10 stronger by forming the blade portion 10 so that the same layer has a large area. Therefore, by molding the knife 1 with the 3D printer 100 so that one of the two sides of the blade portion 10 faces up and the other faces down, it is possible to make the blade portion 10 stronger.

[0058] In addition, in each of the above embodiments, the back portion 12 and the handle portion 20 have a three-dimensional structure by providing multiple cavities 30, but instead of providing multiple cavities 30, they may be formed in a part of a single connected knife 1 other than the cutting edge 13.

[0059] Furthermore, in the above second embodiment, the case where the rib 16 is formed as a structure for improving blade release has been exemplified, but it is also possible to improve blade release by forming a recess or a through hole in a part of the cutting edge portion 11 different from the cutting edge 13. If the knife 1 is molded using the 3D printer 100, such a recess or through hole can be formed from the beginning, which further simplifies the manufacturing process of the knife 1. [Explanation of symbols]

[0060] 1...Knife, 10...Blade, 10a...One side, 10b...Other side, 11...Cutting edge, 12...Back, 13...Edge, 13a...Cutting edge, 13b...Middle of blade, 13c...Jaw, 14...Scratch line, 15...Rib, 16...Rib, 20...Handle, 21...Patent, 22...Patent base, 23...Patent butt, 30...Cavity, 100...3D printer, 101...Printing machine, 102...Control device

Claims

1. The method for manufacturing a knife includes a 3D printing molding step in which a 3D printer (100) is used to mold the entire knife (1), which includes a blade portion (10) including a cutting edge (11) having a cutting edge (13) and a back portion (12) located on the opposite side of the cutting edge of the cutting edge, the thickness of the cutting edge portion gradually decreasing from the back portion side toward the cutting edge, and a handle portion (20) connected to the blade portion.

2. 2. The method for manufacturing a knife as described in claim 1, wherein in the 3D printing process, in addition to a handle portion (21), a handle base (22) that connects the blade portion and the handle portion and gradually increases in dimension from the thickness of the blade portion to the thickness of the handle portion from the blade portion to the handle portion is formed together with the blade portion.

3. 2. The method for manufacturing a knife according to claim 1, wherein in the 3D printing process, the knife is formed by stacking a plurality of layers into the shape of the knife in the 3D printer, and the knife is formed by stacking from the back portion to the cutting edge so that the back portion of the knife faces downward and the cutting edge faces upward.

4. 2. The method for manufacturing a knife according to claim 1, wherein in the 3D printing process, the knife is formed by stacking a plurality of layers into the shape of the knife in the 3D printer, and the knife is formed so that one of both surfaces of the blade portion of the knife faces upward and the other faces downward.

5. The method for manufacturing a kitchen knife according to claim 1, further comprising a sharpening step of sharpening the cutting edge portion including the cutting edge after the 3D printing step.

6. After the 3D printing process, A heat treatment process for hardening the knife; A distortion removing process for removing distortion of the knife that has been subjected to the heat treatment process; The method for manufacturing a knife according to claim 1, further comprising a sharpening step of sharpening the cutting edge portion including the cutting edge of the knife that has been subjected to the straightening step.

7. After the 3D printing process, A heat treatment process for hardening the knife; A distortion removing process for removing distortion of the knife that has been subjected to the heat treatment process; A shot blasting process for roughening the surface of the knife in a location other than the cutting edge of the cutting edge portion of the blade portion of the knife that has been subjected to the distortion removing process; The method for manufacturing a knife according to claim 1, further comprising a sharpening step of sharpening the cutting edge portion including the cutting edge of the knife that has been subjected to the shot blasting step.

8. 8. The method for manufacturing a knife according to claim 1, wherein in the 3D printing molding process, a protruding rib (16) is formed on one side of the blade portion, and the knife is molded so that a position on the other side (10b) opposite to the one side (10a) of the blade portion corresponding to the position where the rib is formed on the one side and a position corresponding to the periphery of the position where the rib is formed are flush with each other.

9. The method for manufacturing a knife according to any one of claims 1 to 7, wherein in the 3D printing process, a three-dimensional structure is formed having a cavity (30) formed by a recessed structure or a penetrating structure in the surface of the knife in at least one of a location of the cutting edge portion of the blade portion different from the cutting edge and the handle portion.

Images