【発明の詳細な説明】[Detailed description of the invention]
本発明は耐摩耗焼結合金よりなる挽肉器用刃物
に関する。
従来、挽肉器用刃物を構成するカツターおよび
カツタープレートは各種工具鋼の機械加工品、銅
溶浸鉄系焼結品などを組合せて使用しているが、
たとえば第１図に示すようなカツタープレートを
工具鋼で造る場合には、多くの穴あけと外形を形
成する切削加工を必要とするとともに、所望の耐
摩耗性を得るためには焼入れ焼もどしの熱処理
と、熱処理による変形を除去し平面度を出すた
め、仕上げに多くの平面研削を必要とする。又第
２図ａの平面図およびｂの側面図に示すようなカ
ツターの場合も精密鋳造によるとしても、焼入れ
焼もどしの熱処理とそれにともなう変形除去のた
めの研削を必要とし、これが品質的にも経済的に
も隘路となつていた。一方たとえば銅溶浸鉄系焼
結品で前記のカツタープレートおよびカツターを
造る場合にも、必要な耐摩耗性を得るために焼入
れ焼もどしの熱処理を要するほか、寸法安定性が
悪いため、所定の寸法精度、平面度などを出すた
めに多くの仕上げ加工を必要とし、工具鋼の場合
と同様に品質的にも経済的にも障害となつてい
た。
又挽肉器用刃物のため牛肉、豚肉、とり肉、羊
肉、馬肉など各種動物肉の切断押出しを行なうた
め、その際に発生する各種固体又は液体物質によ
る刃物の腐食があり、耐食性の面からも従来の刃
物では充分ではなかつた。
本発明は従来の刃物は機械加工を要する、熱処
理を必要とする、熱処理後の変形除去のための多
くの研削を要する、耐食性も充分でないなどの品
質上あるいは多工程による価格上昇等の難点を除
去し簡単な工程で充分な耐摩耗性、耐食性、寿命
などを有し、かつ経済性でも優れた焼結合金を主
体とした挽肉器用刃物を提供することを目的とす
る。
本発明の挽肉器用刃物は鉄系焼結合金よりな
り、ニツケル８〜16重量％、コバルト２〜８重量
％、モリブデン１〜７重量％、炭素0.2〜1.5重量
％および残りが実質的に鉄でなる焼結体で構成さ
れたことを特徴とする。この合金成分のうちニツ
ケルは焼結過程において主として基地に固溶して
基地の硬さと強さを付与するとともに高度な耐食
性を付与する。この効果は８％未満では充分得ら
れず、16％を越えると充分な硬さが得られない。
コバルトは焼結過程においてニツケルと同様に主
として基地に固溶して焼入れ性を高め、基地の硬
さと強さを付与するとともに高度な耐食性を付与
する。この効果は２％未満では充分得られず、８
％を越えると充分な硬さが得られない。モリブデ
ンの一部は基地に固溶して基地を強化するととも
に、焼結時の冷却過程で部分的にマルテンサイト
を生成する。又他の一部は炭素と結合して炭化物
として生成析出する。モリブデンは１％未満では
充分な効果が得られず、７％を越えて含有しても
それに見合つた利点は得られない。炭素は焼結過
程においてその一部がモリブデンと結合して炭化
物を生成し、他の部分は基地に固溶して焼結時の
冷却過程で部分的にマルテンサイトを生成する。
この効果は、0.2％未満では充分でなく、1.5％を
越えると脆化する。
本発明の挽肉器用刃物は、たとえば次のような
方法により得られる。
前記のような所定の成分でなる原料粉末を配合
し、潤滑剤たとえばステアリン酸リチウムを添加
して混合し、たとえば第１図に示すごときカツタ
ープレートを成形する金型に均一に充填し、４〜
７t/cm2程度の圧力で成形後、還元又は真空雰囲気
中で1100〜1300℃の温度範囲で焼結する。焼結体
は第１図ｂの側面図の平面１１の平面度を出すた
め軽く研削する。第２図のカツターの場合も同様
に造られるが、この場合も側面図ｂに示す平面２
１の平面度を出すための軽い平面研削のみでよ
い。本発明の挽肉器用刃物はカツタープレートお
よびカツターの両者とも本発明刃物材料で構成す
るのが好ましいが、目的に応じそのいずれかを本
発明刃物材料以外で構成してもよく、さらにはカ
ツタープレートおよびカツターの一部を本発明品
以外の材料で構成してもよい。
本発明の挽肉器用刃物は、上記の組成の焼結体
で形成することにより、焼結後の熱処理を施こす
ことなく、所定形状に成形したものを焼結するこ
とにより所定の耐摩耗性を得ることができる。し
たがつて熱処理後の変形を修正するための加工も
軽度ですむほか、ニツケル、コバルトを含有する
ため従来のものと比較すると耐食性も良いという
利点を有する。又、寸法安定性が良いことおよび
特別の熱処理が不要であること等が相俟つて工業
的に極めて有利に得ることができる。
以下実施例と比較例について説明する。
実施例と比較例
第１表に示す組成に原料粉末を配合し（Ｉは除
く）、潤滑剤としてステアリン酸リチウム0.75％
を添加してＶミキサーで20分混合後、６t/cm2の圧
力で第１図のカツタープレートおよび又は第２図
のカツターに成形した。ついで水素雰囲気中で
1200℃、40分程度焼結し、焼結炉の冷却部で冷却
した。これら焼結体および焼結体以外の一般材で
焼入れ処理を行なうものは、830℃に30分保持し
たのち、油中に急冷し、180℃で１時間焼もどし
を行なつた。
The present invention relates to a meat grinder cutter made of a wear-resistant sintered alloy. Conventionally, the cutters and cutter plates that make up the cutters for meat grinders have been made of a combination of machined products of various tool steels, copper-infiltrated iron-based sintered products, etc.
For example, when making a cutter plate like the one shown in Figure 1 from tool steel, it requires a lot of drilling and cutting to form the outer shape, and it also requires quenching and tempering to obtain the desired wear resistance. Heat treatment and a lot of surface grinding are required for finishing in order to remove deformation caused by heat treatment and achieve flatness. In addition, even if the cutter shown in the plan view in Figure 2a and the side view in Figure 2b is made by precision casting, it requires heat treatment for quenching and tempering and grinding to remove deformation, which has a negative impact on quality. It was also an economic bottleneck. On the other hand, when making cutter plates and cutters using copper-infiltrated iron-based sintered products, for example, heat treatment of quenching and tempering is required to obtain the necessary wear resistance, and dimensional stability is poor. Many finishing processes were required to achieve dimensional accuracy and flatness, and as with tool steel, this was an obstacle in terms of quality and economy. In addition, the blades used in meat grinders are used to cut and extrude various animal meats such as beef, pork, chicken meat, mutton, and horse meat, so the blades are corroded by the various solid or liquid substances that are generated during this process. The knife was not enough. The present invention solves the disadvantages of conventional cutlery, such as machining, heat treatment, a lot of grinding to remove deformation after heat treatment, insufficient corrosion resistance, and increased costs due to multiple steps. To provide a cutter for a meat grinder mainly made of a sintered alloy, which has sufficient wear resistance, corrosion resistance, and service life through a simple process of removal, and is also excellent in economical efficiency. The meat grinder cutter of the present invention is made of an iron-based sintered alloy, consisting of 8 to 16% by weight of nickel, 2 to 8% by weight of cobalt, 1 to 7% by weight of molybdenum, 0.2 to 1.5% by weight of carbon, and the remainder being substantially iron. It is characterized by being made of a sintered body. Among the alloy components, nickel is mainly dissolved in the matrix during the sintering process, imparting hardness and strength to the matrix and providing a high degree of corrosion resistance. This effect cannot be sufficiently achieved when the content is less than 8%, and sufficient hardness cannot be obtained when the content exceeds 16%.
During the sintering process, like nickel, cobalt mainly dissolves in the matrix to improve hardenability, impart hardness and strength to the matrix, and provide a high degree of corrosion resistance. This effect cannot be sufficiently obtained at less than 2%, and 8%
%, sufficient hardness cannot be obtained. A part of the molybdenum is dissolved in the base to strengthen the base, and martensite is partially generated during the cooling process during sintering. The other part combines with carbon and forms and precipitates as carbide. If molybdenum is contained in an amount less than 1%, no sufficient effect will be obtained, and if it is contained in an amount exceeding 7%, no commensurate advantage will be obtained. During the sintering process, a part of carbon combines with molybdenum to produce carbide, and the other part is solidly dissolved in the matrix and partially forms martensite during the cooling process during sintering.
This effect is not sufficient if it is less than 0.2%, and if it exceeds 1.5%, it becomes brittle. The meat grinder cutter of the present invention can be obtained, for example, by the following method. The raw material powder consisting of the predetermined components as described above is blended, a lubricant such as lithium stearate is added and mixed, and the mixture is uniformly filled into a mold for forming a cutter plate as shown in FIG. ~
After molding at a pressure of about 7 t/cm 2 , it is sintered at a temperature range of 1100 to 1300°C in a reducing or vacuum atmosphere. The sintered body is lightly ground to obtain the flatness of the plane 11 in the side view of FIG. 1b. The cutter shown in Fig. 2 is made in the same way, but in this case also the plane 2 shown in side view b
Only light surface grinding is required to obtain a flatness of 1. In the meat grinder cutter of the present invention, both the cutter plate and the cutter are preferably made of the cutter material of the present invention, but depending on the purpose, either of them may be made of a cutter material other than the cutter material of the present invention. A portion of the plate and cutter may be made of materials other than those of the present invention. The meat grinder cutter of the present invention is formed from a sintered body having the above-mentioned composition, and can be formed into a predetermined shape and sintered to achieve a predetermined wear resistance without the need for post-sintering heat treatment. Obtainable. Therefore, it requires only light processing to correct deformation after heat treatment, and because it contains nickel and cobalt, it has the advantage of better corrosion resistance than conventional products. In addition, the combination of good dimensional stability and no need for special heat treatment makes it extremely advantageous industrially. Examples and comparative examples will be described below. Examples and Comparative Examples Raw material powders were blended into the composition shown in Table 1 (excluding I), and 0.75% lithium stearate was used as a lubricant.
was added and mixed for 20 minutes using a V-mixer, and then molded into a cutter plate as shown in Figure 1 and/or a cutter as shown in Figure 2 under a pressure of 6t/cm2. Then in a hydrogen atmosphere
It was sintered at 1200°C for about 40 minutes and cooled in the cooling section of the sintering furnace. These sintered bodies and general materials other than the sintered bodies to be quenched were held at 830°C for 30 minutes, then quenched in oil and tempered at 180°C for 1 hour.
【表】
つぎに各処理を行なつたものにつき熱処理等に
よる変形を除去し組立てを容易にするため第１図
のカツタープレートの１１、第２図のカツターの
２１の面の平面研削を行ない、平面度、寸法など
を検査ののち、挽肉器に組立て、これに同一条件
の羊肉を約５Kgの押し力で押しながら連続投入
し、10時間／日稼動し10日後、すなわち100時間
後の摩耗度を、その処理量で比較した。各材料の
組合せによる処理量の比較を第２表に示す。[Table] Next, in order to remove the deformation caused by heat treatment etc. and to facilitate assembly, the surfaces 11 of the cutter plate in Fig. 1 and 21 of the cutter in Fig. 2 were subjected to surface grinding. After inspecting flatness, dimensions, etc., it is assembled into a meat grinder, and mutton under the same conditions is continuously fed into it while being pressed with a pushing force of approximately 5 kg. It is operated for 10 hours/day, and the wear is measured after 10 days, that is, 100 hours. The degree of processing was compared based on the amount of processing. Table 2 shows a comparison of the throughput of each material combination.
【表】
第２表の結果より本発明挽肉器用刃物は従来の
刃物と較べて処理量が多く優れた耐摩耗性、寿命
を有し、かつその製造工程が簡単であるなど、優
れた品質と経済性を有することが明らかである。[Table] From the results shown in Table 2, the meat grinder cutlery of the present invention has excellent quality, such as a larger throughput, superior wear resistance, and longer life than conventional cutters, as well as a simple manufacturing process. It is clear that it is economical.
【図面の簡単な説明】[Brief explanation of the drawing]
第１図は本発明の挽肉器用刃物カツタープレー
トの一実施例、第２図は本発明の挽肉器用刃物カ
ツターの一実施例を示す図である。
１１，２１……研削面。
FIG. 1 shows an embodiment of a cutter plate for a meat grinder according to the present invention, and FIG. 2 shows an embodiment of the cutter plate for a meat grinder according to the present invention. 11, 21...Grinding surface.