【０００１】
【発明の属する分野】
本発明は、切断用具に関するもので有り、調理用の包丁や、調理用や事務用や散髪用のハサミ、工作ナイフや鋸、爪切り等を示し、従来の金属の持つ錆びやもろさ、輝きの鈍さや傷つきやすさを解決するものである。
【０００２】
【従来の技術】
従来から刃部または刃先が炭素鋼や、マルテンサイト系ステンレス鋼で作成した切断用具が有る。また先端を固く切れ味を良くするために、コバルト等を使用したステライト等で形成しステンレス鋼等と結合したり、刃部を一体で形成したものが有る。また、例えば包丁の一体のものは柄部をオーステナイト系ステンレス鋼とし刃部をマルテンサイト系ステンレス鋼や炭素鋼とし溶接や鑞付けでつないでいる。従来からネジ類やスプーンにオーステナイト系ステンレス鋼を材料とし炭素固有拡散処理で炭素を固有拡散させ高硬度を得たものは有ったが切断用具及び、これらに属する包丁やハサミに使用したものは無かった。
【０００３】
【解決しようとする課題】
従来から刃が炭素鋼の切断器具は錆びやすく、マルテンサイト系ステンレス鋼（ハイカーボンステンレスとも呼ばれる）の刃も錆びが発生し、硬度が低いため切れ味が悪い上もろい、ステライト材は高価で張り合わせ等にも手間が掛かる上に鋭い刃物とした場合にもろさが有った。またこれらはそれぞれに輝きが無かったり刃先以外の部分が傷つきやすく、美観を損なった。また、柄部と刃部が一体のものにおいては、例えば包丁の一体物等は柄部に刃部を溶接や鑞付けしている為製作に手間や費用が掛かると共に、付け根が異金属の接合の為に電気腐食から錆びの発生を引き起こす原因ともなった。また、調理用の包丁において握りと反対の手を包丁の背に掛けて力を入れて切る際に包丁の背が薄いため手が痛くなる。背を厚くすると重く扱いにくくなる等の問題があった。
【０００４】
【課題を解決するための手段】
請求項１の本発明は、オーステナイト系ステンレス鋼で形成した刃部または、オーステナイト系ステンレス鋼で柄部と刃部を一体形成し、表面に炭素固有拡散処理で炭素を固有拡散させ、表面を表面研磨した切断用具である。
【０００５】
請求項２の本発明は、前記載の請求項の切断用具において、刃部の背に厚味部や折り返しを持たせ補強、または、刃部の背に炭素鋼やチタン材等の曲がり難い金属部材等やコの字等をした曲がりにくい形状の部材等を張り合わせ、または、組合せ補強した、または刃部の背を中空とした切断用具である。
【０００６】
請求項３の本発明は、前記載の請求項１，請求項２の切断用具を肉や魚や野菜等を切る調理用の包丁としたものである。
【０００７】
請求項４の本発明は、前記載の請求項１，請求項２の切断用具を調理用や事務用、散髪等のハサミとしたものである。
【０００８】
上記の各請求項目はオーステナイト系ステンレス鋼を主成分とする刃部を持つ切断用具、及び包丁、ハサミで有り炭素固有拡散処理で炭素を固有拡散する事により刃の表面を硬化させたものである。従来の浸炭技術では金属結晶に炭素が結合し、化合物（セメンタイト組織等）として表面を構成していた為にもろかったり、炭素の析出等により錆びが発生しやすかった。一方炭素固有拡散処理での炭素を固有拡散は結晶の隙間に炭素が入り込む処理であり、炭素の溶出も殆どなく無く、耐摩耗性等にも優れた加工処理である。ステンレス鋼ＳＵＳ３１６では表面よりＨＶ硬度で８００前後で１０μｍの厚味に硬度が得られる結果がとなり、ステンレス鋼ＳＵＳ３０４でもＨＶ硬度６００近くが得られる結果となった。マルテンサイト系ステンレス鋼の硬度はＨＶ硬度３００から４００前後であるのと比べかなりの硬度が得られたと言える。また、表面より２０μｍ付近まで徐々に硬度が低下する事が解った。表面は高硬度であり、内部は低硬度（ＨＶ２００以下）で本来のオーステナイト系ステンレス鋼の性質を示す。表面は固い刃物に適した表面硬化が実現できる。
【０００９】
また、表面を研磨する事により、輝きを増した刃物となると共に、刃先以外の部分も表面硬度が有るために刃部全体が傷つきにくくなる。また、例えば最中状の柄部からなり、柄部と刃部をつないだ形状の包丁においては、刃部と柄部が同一材質のオーステナイト系ステンレス鋼により構成され、表面全体を炭素固有拡散処理での炭素を固有拡散し、表面研磨する事により、柄部を含めた全体が硬度を増し、錆びにくく、全体が傷つきにくくなり、いつまでも美しさを保つ事が出来るものである。
【００１０】
炭素固有拡散処理は炭素を多く含むマルテンサイト系ステンレス鋼には表面硬化の効果が発揮されない。一般にステンレス鋼ＳＵＳ３０４は冷間加工で組織の一部が変態しマルテンサイトを生じるため、加工硬化の発生しやすい加工をさけるか、ステンレス鋼ＳＵＳ３１６等上位の材料を使用する事が必要である。
炭素固有拡散処理での炭素を固有拡散したものは従来の窒化処理に比べ曲げても亀裂や、剥離がおきにくく、錆びにくくなる。
【００１１】
【実施例】
以下、本発明を実施例を図面により具体的に説明する。図１は本発明の実施例を示し、切断用具１は炭素固有拡散処理での炭素を固有拡散した加工表面４を有する刃部２と柄部３で構成するもので刃部２は切断する刃先２ｃを有するものである。
【００１２】
図２は本発明の他の実施例を示し、切断用具１は炭素固有拡散処理での炭素を固有拡散した主に加工表面４を有する刃部２ａと柄部３ａで構成するものである。
【００１３】
図３は本発明の他の実施例を示し、切断用具１は炭素固有拡散処理での炭素を固有拡散した加工表面４を有する刃部２と柄部３及び刃部２の強度を補強する補強部５で構成するものであり、柄部３で補強部５を支えるものを示す。
【００１４】
図４は図３の補強部５のＡ−Ａ断面を示す一例であり刃部２の背に同一材料や炭素鋼等でコの字型の補強部５を取り付けた、または、接合したものを示す。これにより刃部２の曲がり易さを補強したものである。
【００１５】
図５は、本発明の他の実施例を示し平面図に断面図を重ねて図示したものであり、刃部２の内部に炭素鋼等の補強部５ａを封入し刃部２を補強したものを示す。これにより刃部２の曲がり易さを補強したものである。また補強部５ａにチタン材を使用することにより軽量化が期待できる。
【００１６】
図６は本発明の他の実施例を示し平面図に断面を重ねて図示したもので、刃部２ｂの内部が空洞な空洞部６と柄部３ｂの内部が空洞な空洞部７で構成されているものを示す。内部を空洞にすることにより軽量で曲がりにくい丈夫な刃部２ｂを形成すると共に、図示してないが刃部２ｂの背が厚い事により握りと反対の手を包丁の背に掛けて力を入れて切る際に手が痛くない効果が得られる。また、背の角に丸味を付けることにより角があたり痛くなくなり力が入れやすい効果がある。
【００１７】
図７は一例として事務用のハサミの平面図を示し、刃部２ａの背に厚味部２ｄ、または、折り返し２ｅを設けたものを示す。これによりオーステナイト系ステンレス鋼の曲がり易さを軽減することが出来るものである。
【００１８】
図８は図７のＢ−Ｂ断面を示し、図８（ａ）は厚味部２ｄを設けた刃部２ａを示し、図８（ｂ）は折り返し２ｅを設けた刃部２ａを示す。
【００１９】
図９は本発明の他の実施例を示し、切断用具１は炭素固有拡散処理での炭素を固有拡散した加工表面４を有する刃部２と柄部３及び刃部２の強度を補強する補強部５ｂで構成するものであり、補強部５ｂは刃部２に凸面を作り補強すると共に切断物の刃離れを促進する効果もあり、凸形状や凹形状、または切り抜き等でも良いもので有る。また形状も特に規定するものではない。
【００２０】
【発明の効果】
本発明は前述の構成のように、切断用具、及び包丁やハサミを切れ味が長持ちし、丈夫で錆びずにキズが付きにくく、いつまでも美しさを保つものである。一般に普段からの愛用の道具は常に美しく丈夫であってほしいものである。刃部または、一体型とする事により刃部または、全体が傷つきにくくなる為に例えば、汚れがこびり付いた時に、金属タワシ等で擦り落としてもキズがほとんど付かない。これらのことから長期的に渡り使用が可能であり、強いては寿命が長く環境保全にも貢献できる極めて有用な発明と言える。
【００２１】
【図面の簡単な説明】
【図１】本発明の実施例の平面図である。
【図２】本発明の他の実施例の平面図である。
【図３】本発明の他の実施例の平面図である。
【図４】本発明の図３のＡ−Ａ断面図である。
【図５】本発明の他の実施例の平面図に断面図を重ねたものである。
【図６】本発明の他の実施例の平面図に断面図を重ねたものである。
【図７】本発明の他の実施例の平面図である。
【図８】本発明の図７の断面図である。
【図９】本発明の他の実施例の平面図である。
【００２２】
【符号の説明】
１…切断用具
２…刃部
２ａ…刃部
２ｂ…刃部
２ｃ…刃先
２ｄ…厚味部
２ｅ…折り返し
３…柄部
３ａ…柄部
３ｂ…柄部
４…加工表面
５…補強部
５ａ…補強部
５ｂ…補強部
６…空洞部
７…空洞部[0001]
[Field of the Invention]
The present invention relates to cutting tools, such as kitchen knives for cooking, scissors for cooking, office and haircuts, work knives and saws, nail clippers, and the like, and shows the rust, fragility, and shine of conventional metals. It solves dullness and susceptibility to damage.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there is a cutting tool whose cutting portion or cutting edge is made of carbon steel or martensitic stainless steel. Further, in order to improve the sharpness and sharpness of the tip, there is a type which is formed of stellite or the like using cobalt or the like and is combined with stainless steel or the like, or a blade portion is integrally formed. In addition, for example, an integrated knife has a handle portion made of austenitic stainless steel and a blade portion made of martensitic stainless steel or carbon steel, and is connected by welding or brazing. Conventionally, screws and spoons were made of austenitic stainless steel as a material and carbon was inherently diffused by carbon intrinsic diffusion treatment to obtain high hardness, but those used for cutting tools and kitchen knives and scissors belonging to these There was no.
[0003]
[Problem to be solved]
Conventionally, cutting tools made of carbon steel have a tendency to rust, martensitic stainless steel (also called high carbon stainless) blades also rust, and their hardness is low, so they are poorly sharp and fragile. In addition, it takes time and effort, and when a sharp blade is used, it is brittle. In addition, each of them had no luster and was liable to be damaged at portions other than the cutting edge, resulting in impaired appearance. When the handle and the blade are integrated, for example, the integrated knife of the kitchen knife is welded or brazed to the handle, so it takes time and effort to manufacture, and the base is joined to a dissimilar metal. As a result, it also caused rust to occur from electrical corrosion. In addition, when a kitchen knife for cooking is put on the back of the kitchen knife with a hand opposite to the grip and forcibly cut off, the hand is hurt because the back of the kitchen knife is thin. When the back is thick, there is a problem that it becomes heavy and difficult to handle.
[0004]
[Means for Solving the Problems]
According to the first aspect of the present invention, a blade portion made of austenitic stainless steel or a handle portion and a blade portion are integrally formed with austenitic stainless steel, carbon is inherently diffused by a carbon inherent diffusion treatment, and the surface is made to have a surface. This is a polished cutting tool.
[0005]
According to a second aspect of the present invention, there is provided the cutting tool according to the first aspect of the present invention, wherein the blade has a thick portion or a folded portion on the spine for reinforcement or a metal such as carbon steel or titanium material on the spine. This is a cutting tool in which a member or the like or a member having a U-shape or the like that is difficult to be bent is attached or combined and reinforced, or the back of the blade portion is hollow.
[0006]
According to a third aspect of the present invention, the cutting tool according to the first or second aspect is a kitchen knife for cutting meat, fish, vegetables, and the like.
[0007]
According to a fourth aspect of the present invention, the cutting tool of the first and second aspects is a scissor for cooking, office work, haircut, and the like.
[0008]
Each of the above claims is a cutting tool having a blade portion mainly composed of austenitic stainless steel, a kitchen knife, a scissor, and the surface of the blade is hardened by inherently diffusing carbon by a carbon inherent diffusion process. . In the conventional carburizing technique, carbon is bonded to a metal crystal to form a surface as a compound (a cementite structure or the like), so that it is brittle, and rust easily occurs due to precipitation of carbon and the like. On the other hand, the intrinsic diffusion of carbon in the carbon inherent diffusion treatment is a treatment in which carbon enters the gaps between crystals, there is almost no elution of carbon, and it is a processing excellent in wear resistance and the like. In the case of stainless steel SUS316, a hardness of about 10 μm was obtained at an HV hardness of about 800 from the surface, and in the case of stainless steel SUS304, an HV hardness of about 600 was obtained. It can be said that the hardness of the martensitic stainless steel is considerably higher than that of the HV hardness of about 300 to about 400. Further, it was found that the hardness gradually decreased to around 20 μm from the surface. The surface has high hardness, and the inside has low hardness (HV 200 or less) and shows the properties of the original austenitic stainless steel. The surface can achieve surface hardening suitable for a hard blade.
[0009]
In addition, by polishing the surface, the blade becomes more brilliant, and since the portions other than the blade edge also have surface hardness, the entire blade portion is hardly damaged. Further, for example, in a kitchen knife having a middle handle portion and a handle portion and a blade portion connected to each other, the blade portion and the handle portion are made of austenitic stainless steel of the same material, and the entire surface is subjected to a carbon-specific diffusion treatment. By inherently diffusing carbon and polishing the surface, the entire body including the handle increases in hardness, hardly rusts, is hardly damaged, and can maintain its beauty forever.
[0010]
The carbon-specific diffusion treatment does not show the effect of surface hardening on martensitic stainless steel containing a large amount of carbon. Generally, in stainless steel SUS304, a part of the structure is transformed by cold working to generate martensite. Therefore, it is necessary to avoid working in which work hardening easily occurs or to use a higher-order material such as stainless steel SUS316.
The carbon inherently diffused by the carbon inherent diffusion treatment is less likely to crack, peel, and rust even when bent, as compared with the conventional nitriding treatment.
[0011]
【Example】
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. FIG. 1 shows an embodiment of the present invention, in which a cutting tool 1 is composed of a blade portion 2 having a processing surface 4 in which carbon is inherently diffused in a carbon inherent diffusion process and a handle portion 3, and the blade portion 2 is a cutting edge to be cut. 2c.
[0012]
FIG. 2 shows another embodiment of the present invention, in which a cutting tool 1 is composed of a blade portion 2a mainly having a machined surface 4 and a handle portion 3a in which carbon is inherently diffused in a carbon inherent diffusion process.
[0013]
FIG. 3 shows another embodiment of the present invention, in which a cutting tool 1 has a blade portion 2 having a processing surface 4 in which carbon is inherently diffused by a carbon inherent diffusion process, a handle portion 3 and a reinforcement for reinforcing the strength of the blade portion 2. The handle portion 3 supports the reinforcing portion 5 with the handle portion 3.
[0014]
FIG. 4 is an example showing an AA cross section of the reinforcing portion 5 of FIG. 3. The U-shaped reinforcing portion 5 is attached to or joined to the back of the blade portion 2 using the same material or carbon steel. Show. Thereby, the bendability of the blade portion 2 is reinforced.
[0015]
FIG. 5 shows another embodiment of the present invention, in which a sectional view is superimposed on a plan view, in which a reinforcing portion 5a made of carbon steel or the like is sealed inside the blade portion 2 and the blade portion 2 is reinforced. Is shown. Thereby, the bendability of the blade portion 2 is reinforced. Further, by using a titanium material for the reinforcing portion 5a, a reduction in weight can be expected.
[0016]
FIG. 6 shows another embodiment of the present invention, in which a cross-section is superimposed on a plan view. The hollow portion 6b has a hollow portion 6 inside and the handle portion 3b has a hollow portion 7 inside. Show what you are doing. By making the interior hollow, a durable blade portion 2b that is lightweight and hard to bend is formed, and because the back of the blade portion 2b is thick, a hand opposite to the grip is put on the back of the kitchen knife, not shown, to apply force. The effect that the hand does not hurt when cutting is obtained. Also, by rounding the back corners, there is an effect that the corners do not hurt and the force is easily applied.
[0017]
FIG. 7 shows a plan view of office scissors as an example, in which a thick portion 2d or a folded back 2e is provided on the back of the blade portion 2a. As a result, the ease of bending of the austenitic stainless steel can be reduced.
[0018]
8 shows a cross section taken along the line BB of FIG. 7, FIG. 8 (a) shows the blade portion 2a provided with the thick portion 2d, and FIG. 8 (b) shows the blade portion 2a provided with the folded back 2e.
[0019]
FIG. 9 shows another embodiment of the present invention, in which a cutting tool 1 has a blade portion 2 having a processing surface 4 in which carbon is inherently diffused by a carbon inherent diffusion process, a handle portion 3 and a reinforcement for reinforcing the strength of the blade portion 2. The reinforcing portion 5b has an effect of forming a convex surface on the blade portion 2 to reinforce the blade portion 2 and also has an effect of promoting separation of the cut object, and may have a convex shape, a concave shape, or a cutout. Also, the shape is not particularly specified.
[0020]
【The invention's effect】
According to the present invention, as described above, the cutting tool, the kitchen knife and the scissors have a long-lasting sharpness, are durable, are not easily rusted, are not easily scratched, and maintain their beauty forever. In general, your favorite tools always want to be beautiful and durable. Since the blade portion or the integral type makes the blade portion or the whole hard to be damaged, for example, when dirt sticks, it is hardly scratched even if it is scraped off with a metal scrubber or the like. From these facts, it can be said that it is an extremely useful invention that can be used for a long period of time and has a long life and contributes to environmental protection.
[0021]
[Brief description of the drawings]
FIG. 1 is a plan view of an embodiment of the present invention.
FIG. 2 is a plan view of another embodiment of the present invention.
FIG. 3 is a plan view of another embodiment of the present invention.
FIG. 4 is a sectional view taken along line AA of FIG. 3 of the present invention.
FIG. 5 is a plan view of another embodiment of the present invention in which a sectional view is superimposed.
FIG. 6 is a plan view of another embodiment of the present invention, in which a sectional view is superimposed on a plan view.
FIG. 7 is a plan view of another embodiment of the present invention.
8 is a sectional view of FIG. 7 of the present invention.
FIG. 9 is a plan view of another embodiment of the present invention.
[0022]
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cutting tool 2 ... Blade part 2a ... Blade part 2b ... Blade part 2c ... Blade tip 2d ... Thick part 2e ... Folding 3 ... Handle part 3a ... Handle part 3b ... Handle part 4 ... Processing surface 5 ... Reinforcement part 5a ... Reinforcement Part 5b Reinforcement part 6 Cavity part 7 Cavity part
