JP2004114218A

JP2004114218A - Machining wheel

Info

Publication number: JP2004114218A
Application number: JP2002279890A
Authority: JP
Inventors: Yoji Niizawa; 新澤　洋二; Seiya Ogata; 緒方　誠也
Original assignee: Noritake Co Ltd; Noritake Super Abrasive Co Ltd
Current assignee: Noritake Co Ltd; Noritake Super Abrasive Co Ltd
Priority date: 2002-09-25
Filing date: 2002-09-25
Publication date: 2004-04-15
Anticipated expiration: 2022-09-25
Also published as: JP3722792B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a machining wheel which is formed by arranging a layer of abrasive grains on a peripheral surface and peripheral side surfaces of a disk substrate thereof, and brazing the former to the latter by a wax material, wherein the wax material is improved in wrapping force with respect to the abrasive grains and in adhesive strength to the substrate without increasing the amount of wax usage, to thereby prevent slipout of the abrasive grains at the time of machining. <P>SOLUTION: According to the structure of the machining wheel, depressions 4 are formed in the substrate 1 at locations where the abrasive grains are arranged such that part of each abrasive grain 2 is embedded, and while part of the abrasive grain is embedded in each depression, the abrasive grain is fixed to the substrate by the wax material 3. Thus a contact area between the abrasive grain and the wax material is increased to enhance the wrapping force with respect to the abrasive grain by the wax material. At the same time a contact area between the substrate and the wax material is enlarged to enhance the adhesive strength of the wax material to the substrate, to thereby prevent slipout of the abrasive grains at the time of machining. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、コンクリート、セメント系建材、れんが、セラミックス、その他硬質材料の切断や研削に用いられる加工用ホイールに係り、詳しくは、基板に一層配列する砥粒のろう付け状態を改良して砥粒の保持力を向上させた加工用ホイールに関する。
【０００２】
【従来の技術】
コンクリート、セメント系建材、レンガ、セラミックス、その他硬質材料の切断用として、円盤状基板の外周部に砥粒をろう付け法により一層配列した加工用ホイールが使用されている。このような加工用ホイールには、切れ味に優れ、しかもその切れ味が長期にわたって安定的に持続することが要求される。ところが、加工用ホイールは加工作業の進行に伴い切れ味と寿命が低下する。
【０００３】
その主な原因として、基板への砥粒の固着状態が不安定で砥粒が脱落しやすいこと、チップポケットが小さいこと、砥粒間隔のコントロールが不十分なために加工作業中に切粉によって目詰まりが生じることが挙げられる。とくに基板への砥粒の固着状態が不安定であると加工中に砥粒が脱落しやすく、加工作業が続行できなくなってホイールの寿命となる。
【０００４】
基板への砥粒の固着は、たとえば、鉄製基板の外周面と外周部側面に塗布した有機接着剤の上にダイヤモンド砥粒を配置し、これを乾燥炉中で乾燥させて砥粒を仮固定した後、接着部にＡｇ−Ｃｕ−Ｔｉ系の活性金属入りろう材とバインダーの混合物を砥粒粒径の約１／２の高さに塗布し、これを非酸化性雰囲気中で１０００℃、１時間程度加熱して、砥粒を基板に本固定する工程により行われる。
【０００５】
前記の工程において、鉄製基板とＡｇ−Ｃｕ−Ｔｉ系のろう材とは互いに濡れ性が悪いので、ろう材は基板に直接塗布せずに、有機接着剤を介して基板に塗布している。そして、砥粒の保持力は実質的にろう材の抱き力に依存する状態になる。このことを考慮して、ダイヤモンド砥粒を直立させた状態でろう材により基板に接続し、そのろう材接合厚さを砥粒の大きさに対応させ０．０２〜０．１ｍｍとした砥石が提案されている（たとえば特許文献１参照）。この砥石によれば、放熱性に優れ、砥粒の保持力が向上するとされている。
【０００６】
また、台金の表面部に複数本のＶ溝を平行にかつ等間隔状に設け、このＶ溝に砥粒を設け、これらの砥粒をろう材を介して取り付けた砥石が提案されている（たとえば特許文献２）。この砥石によれば、砥粒は強固に台金上に保持されるとされている。
【０００７】
【特許文献１】
特開平１０−１３８１４７号公報（段落番号０００９）
【特許文献２】
特開平１０−３４５４０号公報（段落番号０００４−０００５）
【０００８】
【発明が解決しようとする課題】
しかしながら、特許文献１に記載の砥石においては、ダイヤモンド砥粒を基板に直立させる手段として、静電植毛の原理を利用する方法が例示されているが、このような方法による作業は非常に面倒であり、またすべての砥粒が直立した状態となる保証はない。
また、特許文献２に記載の砥石においては、Ｖ溝内のペースト状混合物のところに砥粒を上方からばらまいて付着させるときに、Ｖ溝内の砥粒の間隔が不揃いの状態になり、とくに団子状につながった場合は、隣り合う砥粒どうしの間に隙間がなく、ろう材による砥粒の保持が不十分になるという問題がある。
【０００９】
また、上記特許文献１に記載の砥石も含めて従来のろう付けにより砥粒を固着した加工用ホイールにおいては、砥粒の保持力を専らろう材の抱き力に依存している。砥粒の保持力を高めるには、ろう材による砥粒の埋め込み量を増やすことになるが、砥粒の埋め込み量を増やすと砥粒の突き出し量が少なくなって切れ味が低下し、また、高価なろう材が大量に必要となり、製造コストの上昇を招く。
切れ味を良くするために砥粒の突き出し量を多くとると、ろう材による砥粒の保持力が低下する。また、基板とろう材の接着力が不充分であると、ろう材が基板から剥離するので、基板とろう材の接着力を高めることも必要である。
【００１０】
本発明が解決すべき課題は、ろう付けにより砥粒を基板に固着した加工用ホイールにおいて、ろう材の使用量を増加させることなくろう材による砥粒の抱き込み力および基板に対するろう材の接着力を高めて、加工時の砥粒の脱落防止をはかることにある。
【００１１】
【課題を解決するための手段】
本発明は、円盤状基板の外周面および外周部側面に砥粒を一層配列してろう付けした加工用ホイールであって、基板の砥粒配設位置に砥粒の一部が埋没する凹部を形成し、この凹部に砥粒の一部を埋め込んだ状態でろう材により砥粒を基板に固着した加工用ホイールである。
【００１２】
砥粒の一部を基板に形成した凹部に埋め込んだ状態でろう材により基板に固着することで、ろう材の使用量を増やすことなく砥粒とろう材の接着面積を増やして、ろう材による砥粒の抱き込み力を高めることができる。同時に、ろう材の使用量を増すことなく基板とろう材との接着面積を拡大することができて、基板に対するろう材の接着力も高くなる。
【００１３】
ここで、基板に形成する凹部の深さを、砥粒粒径の１０〜３０％とするのが望ましい。凹部の深さが砥粒粒径の１０％より浅いと、砥粒とろう材および基板とろう材との接着面積の拡大効果がなく、３０％より深くなると砥粒の突出高さが低くなって切れ味が低下する。
【００１４】
また、前記凹部の基板回転方向後部側に、砥粒粒径の３０〜５０％の高さの突起を形成することもできる。このような突起を凹部の基板回転方向後部側に形成することにより、凹部に砥粒を固着したホイールで硬質材料の切断、研削加工を行う際に、砥粒にかかる加工時の衝撃を基板に形成した突起が受け止めることによって、砥粒が破壊するのを防止することができる。この場合、突起の高さが砥粒粒径の３０％より低いと、衝撃を受け止める作用が弱く、砥粒の破壊を防止する効果が発揮できない。一方、５０％より高い突起では、この突起が被加工材と擦れ、切れ味が低下するので好ましくない。
【００１５】
上記の突起はすべての凹部に対して形成してもよいが、基板製作の作業性の点から、突起形成の効果が特に著しい基板の外周面の範囲についてのみ突起を形成するようにしてもよい。突起の形状は、凹部に近いところから基板回転方向後方側に向けて次第に突起高さが低くなる形状とするのが、突起が被加工材と干渉し擦れて切れ味が低下するということがない、という点から適当である。
【００１６】
【発明の実施の形態】
図１は本発明の実施形態の加工用ホイールを示す図であり、（ａ）は加工用ホイールの正面図、（ｂ）は（ａ）のＡ−Ａ線断面図である。図２は図１のホイールの基板外周部の部分拡大断面図であり、（ａ）は正面断面図、（ｂ）は側面断面図である。図中、砥粒および砥粒の配置は模式的に示している。
【００１７】
本実施形態のホイール１０は、コンクリートやセメント系建材などの切断用のホイールである。基板１は外径１００ｍｍ、厚さ２．５ｍｍの調質鋼製基板であり、砥粒２は平均粒径が３５０μｍ（基板厚さの１４％）のダイヤモンド砥粒であり、ろう材３はＡｇ−Ｃｕ−Ｔｉ系の活性金属入りろうである。
【００１８】
基板１の外周部には切粉排出のためのスリット１１が形成され、各スリット１１の間に砥粒２が配設されている。基板１の外周部には、外周面１ａに１列、外周部側面１ｂに２列、砥粒２が基板周方向に間隔をおいて配設され、ろう材３により基板１に固着されている。
【００１９】
つぎに砥粒２の固着状態について説明する。本実施形態のホイール１０においては、図２の（ａ）および（ｂ）に示すように、基板１の砥粒配設位置に砥粒２の一部が埋没する凹部４を形成し、この凹部４に砥粒２の一部を埋め込んだ状態でろう材３により砥粒２を基板１に固着している。砥粒の配設位置そのものは従来のホイールの場合と同様な基準により定めたものである。
【００２０】
凹部４は球面の一部をなす形状で、その深さは０．０７ｍｍ（砥粒粒径の約２０％）である。このような凹部４に砥粒２の一部を埋め込んでろう材３により固着することで、ろう材３の使用量を従来のホイールの場合よりも少なくしたうえで砥粒２とろう材３の接着面積を増やして、ろう材３による砥粒２の抱き込み力を高めることができる。同時に、ろう材３の使用量を増すことなく基板１とろう材３との接着面積も拡大するので、基板１に対するろう材３の接着力も高くなる。
【００２１】
図３は砥粒の固着形態の別の例を示す図である。この例では、基板１のスリット１１に近い砥粒配設位置２箇所の凹部４の基板回転方向（図中、矢印で示す方向）の後部側に、砥粒粒径の約４０％の高さの突起５を形成している。このような突起５は、突起のない基板にロレット様の塑性加工を施すことにより形成することができる。これらの突起５を凹部３の基板回転方向後部側に形成することにより、このホイールを用いて加工を行う際に、砥粒２にかかる加工時の衝撃を突起５が受け止めることによって、砥粒２が破壊するのを防止することができる。
【００２２】
第１の実施形態のホイール１０の製造手順はつぎの通りである。
・基板１として外径１００ｍｍ、厚さ２．５ｍｍのスチール製基板を準備する。・砥粒２として平均粒径３５０μｍのダイヤモンド砥粒を準備する。
・基板１の砥粒配設位置に凹部３を形成する。
・直径０．５ｍｍの孔を砥粒配設位置に対応させて配列したスクリーンを用いて、基板１の凹部３に有機接着剤を塗布する。
・この有機接着剤の上に砥粒２を配置する。この状態で砥粒２は基板１の外周面１ａと外周部側面１ｂに図２に示すかたちに配列される。
・これを乾燥炉中で１２０℃、１時間乾燥させ、砥粒２を仮固定する。
・三次元移動が可能なアプリケータ（吐出機）を用いて、凹部４と砥粒２の間および砥粒周囲にろう材とバインダーの混合物を砥粒粒径の約１／２の高さに塗布する。
・これを非酸化性雰囲気中で１０００℃、１時間加熱し、砥粒を台金に本固定する。
図３の実施例のホイールの製造手順も、基本的には上記の製造手順と同様である。
【００２３】
〔試験例〕
図１に示した実施形態のホイール（発明品１）と図３に示した実施例のホイール（発明品２）、および、第１実施形態の基板と同じ形状で同じ数の砥粒を凹部を形成することなく配設したホイール（従来品）を製造して切断加工試験を行った。
【００２４】
〔試験条件〕
切断機械　：日立製丸のこ　Ｃ４ＹＡ１
機械回転速度：１３０００ｍｉｎ^−１
被切断材　：押し出し成形セメント板
切り込み量：１５ｍｍ／ｐａｓｓ
切断方式　：乾式切断
送り速度　：負荷電流８Ａになるよう調節
【００２５】
表１に試験結果を示す。
【表１】

【００２６】
発明品１，２の切断速度およびホイール寿命は、従来品の切断速度およびホイール寿命を１００としたときの指数で示す。同表からわかるように、砥粒配設位置に凹部を形成して砥粒を固着させた発明品１，２のホイールは、従来品のホイールに比べて切断速度は同等であるが、ホイール寿命は１．５倍〜３倍程度に向上している。従来のホイールの場合は、加工時に砥粒先端の大破壊が生じて短寿命となるが、発明品１のホイールでは砥粒先端の微小破壊だけですみ、発明品２のホイールでは砥粒先端の微小破壊も生じないので、発明品１，２は長寿命となる。
【００２７】
【発明の効果】
基板の砥粒配設位置に砥粒の一部が埋没する凹部を形成し、この凹部に砥粒の一部を埋め込んだ状態でろう材により砥粒を基板に固着することで、ろう材の使用量を増やすことなく砥粒とろう材の接着面積を増やして、ろう材による砥粒の抱き込み力を高めることができる。同時に、ろう材の使用量を増すことなく基板とろう材との接着面積を拡大することができて、基板に対するろう材の接着力も高くなり、加工時における砥粒の脱落を防止することができる。
【図面の簡単な説明】
【図１】本発明の実施形態の加工用ホイールを示す図であり、（ａ）は加工用ホイールの正面図、（ｂ）は（ａ）のＡ−Ａ線断面図である。
【図２】図１の加工用ホイールの基板外周部の部分拡大断面図であり、（ａ）は正面断面図、（ｂ）は側面断面図である。
【図３】砥粒の固着形態の別の例を示す部分拡大断面図である。
【符号の説明】
１　基板
１ａ　外周面
１ｂ　外周部側面
２　砥粒
３　ろう材
４　凹部
５　突起
１０　ホイール
１１　スリット[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a processing wheel used for cutting and grinding concrete, cement-based building materials, bricks, ceramics, and other hard materials. The present invention relates to a processing wheel with improved holding power.
[0002]
[Prior art]
BACKGROUND ART For cutting concrete, cement-based building materials, bricks, ceramics, and other hard materials, a processing wheel in which abrasive grains are arranged on the outer peripheral portion of a disk-shaped substrate by brazing is used. Such a processing wheel is required to be excellent in sharpness and to stably maintain the sharpness over a long period of time. However, the sharpness and the life of the processing wheel decrease with the progress of the processing operation.
[0003]
The main reasons for this are that the abrasive grains are stuck to the substrate in an unstable state and the abrasive grains easily fall off, chip pockets are small, and the gap between the abrasive grains is insufficiently controlled. Clogging may occur. In particular, if the state of fixation of the abrasive grains to the substrate is unstable, the abrasive grains are likely to fall off during processing, and the working operation cannot be continued, and the life of the wheel will be shortened.
[0004]
To fix the abrasive grains to the substrate, for example, place diamond abrasive grains on the outer peripheral surface of the iron substrate and the organic adhesive applied to the outer peripheral side surface, dry it in a drying furnace, and temporarily fix the abrasive grains After that, a mixture of an Ag-Cu-Ti-based brazing filler metal containing active metal and a binder is applied to the bonding portion to a height of about 1/2 of the abrasive grain diameter, and this is applied at 1000 ° C in a non-oxidizing atmosphere. This is performed by a step of heating the abrasive for about one hour to permanently fix the abrasive grains to the substrate.
[0005]
In the above process, since the iron substrate and the Ag-Cu-Ti-based brazing material have poor wettability with each other, the brazing material is not directly applied to the substrate but is applied to the substrate via an organic adhesive. Then, the holding force of the abrasive grains substantially depends on the holding force of the brazing material. In consideration of this, a grindstone which is connected to the substrate with a brazing material in a state where the diamond abrasive grains are upright and the brazing material bonding thickness is set to 0.02 to 0.1 mm corresponding to the size of the abrasive grains. It has been proposed (for example, see Patent Document 1). According to this whetstone, it is said that the heat dissipation is excellent and the holding power of the abrasive grains is improved.
[0006]
In addition, a grindstone has been proposed in which a plurality of V-grooves are provided in parallel on the surface of a base metal at equal intervals, abrasive grains are provided in the V-grooves, and these abrasive grains are attached via a brazing material. (For example, Patent Document 2). According to this grinding stone, the abrasive grains are firmly held on the base metal.
[0007]
[Patent Document 1]
JP-A-10-138147 (paragraph number 0009)
[Patent Document 2]
JP-A-10-34540 (paragraph number 0004-0005)
[0008]
[Problems to be solved by the invention]
However, in the whetstone described in Patent Document 1, as a means for erecting diamond abrasive grains on a substrate, a method utilizing the principle of electrostatic flocking is exemplified, but the work by such a method is very troublesome. Yes, and there is no guarantee that all abrasive grains will be upright.
Further, in the grindstone described in Patent Document 2, when abrasive grains are dispersed and adhered to the paste-like mixture in the V-groove from above, the intervals of the abrasive grains in the V-groove become uneven, and particularly, When connected in a dumpling manner, there is no gap between adjacent abrasive grains, and there is a problem that the holding of the abrasive grains by the brazing material becomes insufficient.
[0009]
Further, in a processing wheel to which abrasive grains are fixed by conventional brazing, including the grindstone described in Patent Document 1, the holding force of the abrasive grains mainly depends on the holding force of the brazing material. To increase the holding power of the abrasive grains, the amount of embedding of the abrasive grains by the brazing material is increased, but if the amount of embedding of the abrasive grains is increased, the protrusion amount of the abrasive grains is reduced, the sharpness is reduced, and the cost is high. A large amount of brazing material is required, leading to an increase in manufacturing costs.
When the protrusion amount of the abrasive grains is increased to improve the sharpness, the holding power of the abrasive grains by the brazing material is reduced. In addition, if the adhesive strength between the substrate and the brazing material is insufficient, the brazing material will peel off from the substrate, so it is necessary to increase the adhesive strength between the substrate and the brazing material.
[0010]
The problem to be solved by the present invention is that in a processing wheel in which abrasive grains are fixed to a substrate by brazing, the embracing force of the abrasive grains by the brazing material and the adhesion of the brazing material to the substrate without increasing the amount of brazing material used. The purpose is to increase the force to prevent the abrasive grains from falling off during processing.
[0011]
[Means for Solving the Problems]
The present invention is a processing wheel in which abrasive grains are arranged and brazed on the outer peripheral surface and the outer peripheral side surface of the disk-shaped substrate, and a concave portion in which a part of the abrasive particles is buried is provided at the abrasive particle disposing position of the substrate. A processing wheel in which abrasive grains are formed and fixed to a substrate with a brazing material in a state where abrasive grains are partially embedded in the recesses.
[0012]
By fixing a part of the abrasive grains to the substrate with the brazing material embedded in the recess formed in the substrate, the bonding area between the abrasive grains and the brazing material is increased without increasing the amount of brazing material, and The holding force of the abrasive grains can be increased. At the same time, the bonding area between the substrate and the brazing material can be increased without increasing the amount of the brazing material used, and the bonding strength of the brazing material to the substrate also increases.
[0013]
Here, it is desirable that the depth of the concave portion formed in the substrate is 10 to 30% of the grain diameter of the abrasive grains. If the depth of the recess is less than 10% of the abrasive grain size, there is no effect of increasing the bonding area between the abrasive and the brazing material and between the substrate and the brazing material. If the depth is more than 30%, the projection height of the abrasive becomes low. The sharpness decreases.
[0014]
Further, a projection having a height of 30 to 50% of the abrasive particle diameter may be formed on the rear side of the recess in the substrate rotation direction. By forming such projections on the rear side of the concave portion in the substrate rotation direction, when cutting and grinding a hard material with a wheel having abrasive particles fixed to the concave portion, the impact of the processing applied to the abrasive particles on the substrate is performed on the substrate. By receiving the formed protrusion, it is possible to prevent the abrasive grains from being broken. In this case, if the height of the projections is less than 30% of the particle diameter of the abrasive grains, the effect of receiving the impact is weak, and the effect of preventing the breakage of the abrasive grains cannot be exerted. On the other hand, a projection higher than 50% is not preferable because the projection rubs against the workpiece and the sharpness is reduced.
[0015]
The above-mentioned protrusions may be formed in all the concave portions, but from the viewpoint of the workability of manufacturing the substrate, the protrusions may be formed only in the range of the outer peripheral surface of the substrate where the effect of forming the protrusion is particularly remarkable. . The shape of the projection is such that the height of the projection gradually decreases from the position near the recess toward the rear side in the substrate rotation direction, so that the protrusion does not interfere with the workpiece and the sharpness does not decrease, It is appropriate in that respect.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
1A and 1B are diagrams showing a processing wheel according to an embodiment of the present invention, wherein FIG. 1A is a front view of the processing wheel, and FIG. 1B is a cross-sectional view taken along line AA of FIG. 2A and 2B are partially enlarged sectional views of the outer peripheral portion of the substrate of the wheel of FIG. 1, wherein FIG. 2A is a front sectional view and FIG. 2B is a side sectional view. In the figure, the abrasive grains and the arrangement of the abrasive grains are schematically shown.
[0017]
The wheel 10 of the present embodiment is a wheel for cutting concrete, cement-based building materials, and the like. The substrate 1 is a tempered steel substrate having an outer diameter of 100 mm and a thickness of 2.5 mm, the abrasive grains 2 are diamond abrasive grains having an average grain diameter of 350 μm (14% of the substrate thickness), and the brazing material 3 is made of Ag. -It is an active metal containing Cu-Ti.
[0018]
Slits 11 for discharging chips are formed in the outer peripheral portion of the substrate 1, and abrasive grains 2 are arranged between the slits 11. On the outer peripheral portion of the substrate 1, one row is provided on the outer peripheral surface 1 a and two rows are provided on the outer peripheral side surface 1 b at intervals in the circumferential direction of the substrate, and are fixed to the substrate 1 by the brazing material 3. .
[0019]
Next, the fixed state of the abrasive grains 2 will be described. In the wheel 10 of the present embodiment, as shown in FIGS. 2A and 2B, a concave portion 4 in which a part of the abrasive grains 2 is buried is formed at a position where the abrasive grains are provided on the substrate 1. The abrasive grains 2 are fixed to the substrate 1 by a brazing material 3 in a state where a part of the abrasive grains 2 is embedded in the substrate 4. The positions at which the abrasive grains are arranged are determined based on the same standards as in the case of the conventional wheel.
[0020]
The concave portion 4 has a shape which forms a part of a spherical surface, and has a depth of 0.07 mm (about 20% of the abrasive particle diameter). By embedding a part of the abrasive 2 in such a concave portion 4 and fixing it with the brazing material 3, the amount of the brazing material 3 used is made smaller than that of the conventional wheel, By increasing the bonding area, the force of holding the abrasive grains 2 by the brazing material 3 can be increased. At the same time, since the bonding area between the substrate 1 and the brazing material 3 is increased without increasing the amount of the brazing material 3 used, the adhesive strength of the brazing material 3 to the substrate 1 is also increased.
[0021]
FIG. 3 is a view showing another example of the form of fixing the abrasive grains. In this example, a height of about 40% of the grain size of the abrasive grains is provided on the rear side of the concave portion 4 at two positions where the abrasive grains are provided near the slit 11 of the substrate 1 in the substrate rotation direction (the direction indicated by the arrow in the figure). Are formed. Such projections 5 can be formed by subjecting a substrate without projections to knurl-like plastic working. By forming these projections 5 on the rear side of the concave portion 3 in the substrate rotation direction, when processing is performed using this wheel, the projections 5 receive the impact of the processing on the abrasive grains 2, whereby the abrasive grains 2 are received. Can be prevented from being destroyed.
[0022]
The manufacturing procedure of the wheel 10 according to the first embodiment is as follows.
A steel substrate having an outer diameter of 100 mm and a thickness of 2.5 mm is prepared as the substrate 1. A diamond abrasive having an average particle diameter of 350 μm is prepared as the abrasive 2.
The recess 3 is formed at the position where the abrasive grains are provided on the substrate 1.
An organic adhesive is applied to the concave portion 3 of the substrate 1 using a screen in which holes having a diameter of 0.5 mm are arranged corresponding to the positions where the abrasive grains are provided.
-Arrange the abrasive grains 2 on the organic adhesive. In this state, the abrasive grains 2 are arranged on the outer peripheral surface 1a and the outer peripheral side surface 1b of the substrate 1 as shown in FIG.
-This is dried in a drying furnace at 120 ° C for 1 hour, and the abrasive grains 2 are temporarily fixed.
-Using a three-dimensionally movable applicator (discharger), the mixture of the brazing filler metal and the binder is formed between the recess 4 and the abrasive grains 2 and around the abrasive grains to a height of about 1/2 of the abrasive grain diameter. Apply.
Heating this in a non-oxidizing atmosphere at 1000 ° C. for 1 hour to permanently fix the abrasive grains to the base metal.
The manufacturing procedure of the wheel of the embodiment in FIG. 3 is basically the same as the above-described manufacturing procedure.
[0023]
(Test example)
The wheel (invention 1) of the embodiment shown in FIG. 1 and the wheel (invention 2) of the embodiment shown in FIG. 3 and the same shape and the same number of abrasive grains as the substrate of the first embodiment are recessed. A cutting test was performed by manufacturing a wheel (conventional product) disposed without forming.
[0024]
〔Test condition〕
Cutting machine: Hitachi circular saw C4YA1
Machine rotation speed: 13000 min ^-1
Material to be cut: Extruded cement board Cut depth: 15 mm / pass
Cutting method: Dry cutting feed rate: Adjusted so that the load current becomes 8A.
Table 1 shows the test results.
[Table 1]

[0026]
The cutting speed and wheel life of the

invention products

1 and 2 are indicated by an index when the cutting speed and wheel life of the conventional product are set to 100. As can be seen from the table, the wheels of the

inventions

1 and 2 in which the abrasive grains are fixed by forming a concave portion at the abrasive grain arrangement position have the same cutting speed as the conventional wheel, but the wheel life Is improved about 1.5 to 3 times. In the case of the conventional wheel, a large breakage of the tip of the abrasive grain occurs during processing, resulting in a short life. However, in the wheel of the invention 1, only a small breakage of the tip of the abrasive grain is required. Since no minute destruction occurs, the

inventions

1 and 2 have a long life.
[0027]
【The invention's effect】
By forming a recess in which a part of the abrasive grains are buried at the position where the abrasive grains are provided on the substrate, and fixing the abrasive grains to the substrate with a brazing material in a state in which the abrasive grains are partially embedded in the recess, the It is possible to increase the bonding area between the abrasive grains and the brazing material without increasing the amount of use, thereby increasing the embracing force of the abrasive grains by the brazing material. At the same time, the bonding area between the substrate and the brazing material can be increased without increasing the amount of the brazing material used, and the bonding strength of the brazing material to the substrate also increases, thereby preventing the abrasive grains from dropping during processing. .
[Brief description of the drawings]
FIG. 1 is a view showing a processing wheel according to an embodiment of the present invention, wherein (a) is a front view of the processing wheel, and (b) is a cross-sectional view taken along line AA of (a).
FIGS. 2A and 2B are partially enlarged cross-sectional views of the outer peripheral portion of the substrate of the processing wheel of FIG. 1, wherein FIG. 2A is a front cross-sectional view and FIG.
FIG. 3 is a partially enlarged cross-sectional view showing another example of a form of fixing abrasive grains.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Substrate 1a Outer peripheral surface 1b Outer peripheral side surface 2 Abrasive grain 3 Brazing material 4 Concave part 5 Projection 10 Wheel 11 Slit

Claims

A processing wheel in which abrasive grains are further arranged and brazed on the outer peripheral surface and the outer peripheral side surface of the disk-shaped substrate, and a concave portion in which a part of the abrasive particles is buried is formed at the position where the abrasive particles are provided on the substrate. A processing wheel in which abrasive grains are fixed to a substrate with a brazing filler metal with a portion of the abrasive grains embedded in the recess.

The processing wheel according to claim 1, wherein a depth of the concave portion is set to 10 to 30% of an abrasive particle diameter.

The processing wheel according to claim 1, wherein a projection having a height of 30 to 50% of an abrasive particle diameter is formed on a rear side of the recess in the substrate rotation direction.