JPS6323507Y2 - - Google Patents
Info
- Publication number
- JPS6323507Y2 JPS6323507Y2 JP1985197168U JP19716885U JPS6323507Y2 JP S6323507 Y2 JPS6323507 Y2 JP S6323507Y2 JP 1985197168 U JP1985197168 U JP 1985197168U JP 19716885 U JP19716885 U JP 19716885U JP S6323507 Y2 JPS6323507 Y2 JP S6323507Y2
- Authority
- JP
- Japan
- Prior art keywords
- base metal
- bit
- groove
- head
- blade
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000010953 base metal Substances 0.000 claims description 47
- 238000005520 cutting process Methods 0.000 claims description 14
- 238000005552 hardfacing Methods 0.000 claims description 9
- 239000000463 material Substances 0.000 claims description 9
- 229910000831 Steel Inorganic materials 0.000 claims description 8
- 239000010959 steel Substances 0.000 claims description 8
- 238000005219 brazing Methods 0.000 claims description 5
- 229910000679 solder Inorganic materials 0.000 description 7
- 230000002093 peripheral effect Effects 0.000 description 4
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 238000009412 basement excavation Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000005255 carburizing Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- VNTLIPZTSJSULJ-UHFFFAOYSA-N chromium molybdenum Chemical compound [Cr].[Mo] VNTLIPZTSJSULJ-UHFFFAOYSA-N 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 230000001141 propulsive effect Effects 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000003566 sealing material Substances 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Earth Drilling (AREA)
Description
【考案の詳細な説明】
［産業上の利用分野］
この考案は、土木工事等に用いられる切削ビツ
トに関するものである。[Detailed description of the invention] [Industrial field of application] This invention relates to a cutting bit used in civil engineering work, etc.
［従来の技術］
鋼製の台金の頭部に超硬チツプ等の刃体を植設
してなる種々の切削ビツトが鉱山や土木工事現場
で広く使用されている。[Prior Art] Various cutting bits are widely used in mines and civil engineering construction sites, and are made of a steel base with a blade made of carbide or the like embedded in the head.
［考案が解決しようとする問題点］
上記従来のビツトは、硬質金属である超硬チツ
プが摩耗する前に比較的軟らかい材質でつくられ
た台金の頭部が摩耗し、刃体が台金から大きく突
出して欠損したり脱落したりするという問題点が
あつた。[Problems to be solved by the invention] In the above-mentioned conventional bit, the head of the base metal made of a relatively soft material wears out before the carbide tip, which is a hard metal, wears out, and the blade body becomes attached to the base metal. There was a problem that a large protrusion would protrude from the surface and cause damage or fall off.
［問題点を解決するための手段］
本考案は上記問題点を解決するために次のよう
な構成とした。[Means for Solving the Problems] In order to solve the above problems, the present invention has the following configuration.
すなわち、本考案にかかる切削ビツトは、鋼製
の台金の頭部に形成した溝に硬質刃体をろう材で
固着してなる切削ビツトであつて、前記台金の頭
部に硬化肉盛層を形成するとともに、台金の溝に
植設された前記硬質刃体と台金の境界部には、硬
化肉盛層が形成されていない細幅の台金露出部を
設けたことを特徴としている。 That is, the cutting bit according to the present invention is a cutting bit in which a hard blade is fixed to a groove formed in the head of a steel base metal with a brazing material, and the head of the base metal is hardened. In addition to forming a layer, a narrow exposed portion of the base metal in which the hardfacing layer is not formed is provided at the boundary between the hard blade and the base metal, which are implanted in the groove of the base metal. It is said that
［作用］
台金頭部が硬化肉盛層によつて保護される。硬
化肉盛層は、ビツト頭部に形成されているが、刃
体と台金の境界部にはこの肉盛層が形成されてい
ないので、この部分における刃体側の残留応力と
台金側の残留応力の差が著しく大きくならず、チ
ツプの欠損や脱落等が生じにくい。[Function] The base metal head is protected by the hardfacing layer. A hardfacing layer is formed on the bit head, but this layer is not formed at the boundary between the blade and the base metal, so the residual stress on the blade side and the base metal side in this area are The difference in residual stress does not become significantly large, making it difficult for chips to break or fall off.
［実施例］
以下、図面にあらわされた実施例について詳し
く説明する。[Example] Hereinafter, the example shown in the drawings will be described in detail.
第１図は本考案にかかる切削ビツトの１例とし
てのローラビツトの使用状態を示す説明図であ
る。ローラビツトは掘削装置２の回転ヘツド３に
適当な間隔をおいて複数個取り付けられる。回転
ヘツド３の回転によつて、各ローラビツト１はそ
れ自体が切羽面５との摩擦抵抗で回転しつつ、切
羽面５上を同心円の軌跡を描いて転動する。この
とき、ローラビツト１は掘削装置２の推進力で切
羽面５に押圧されているので、ローラビツトの刃
先部によつて破砕が行なわれるのである。 FIG. 1 is an explanatory view showing how a roller bit is used as an example of the cutting bit according to the present invention. A plurality of roller bits are attached to the rotating head 3 of the excavating device 2 at appropriate intervals. As the rotary head 3 rotates, each roller bit 1 rotates by frictional resistance with the face 5 and rolls on the face 5 in a concentric trajectory. At this time, since the roller bit 1 is pressed against the face 5 by the propulsive force of the excavation device 2, the cutting edge of the roller bit performs the crushing.
第２図は本考案にかかるローラビツトの取付状
態を例示する部分断面図、第３図はその側面図で
ある。ローラビツト１は、掘削装置２の回転ヘツ
ド３に溶接された取付台６と、これに固着される
蓋体６ａ、該取付台６と蓋体６ａによつて両端を
支持され、ピン８で固定された段付きの固定軸
７、および回転軸受１０等によつて構成される支
承部品によつて掘削装置２に取り付けられる。回
転軸受１０の内周側１０ａは固定軸７の大径部７
ａに、外周側１０ｂは台金９の内壁９ａにそれぞ
れ接触しており、台金９は固定軸７の周囲を自由
に回転することができるように支持されている。
１１と１２はシールカバーおよびシール材であ
り、回転軸受１０の潤滑油保持部を密封してい
る。１４ａはシールカバー取付けボルト、１４ｂ
は蓋体固定ボルトである。 FIG. 2 is a partial sectional view illustrating the mounting state of the roller bit according to the present invention, and FIG. 3 is a side view thereof. The roller bit 1 includes a mounting base 6 welded to a rotating head 3 of an excavation device 2, a lid body 6a fixed to this, both ends supported by the mounting base 6 and the lid body 6a, and fixed with pins 8. The excavator 2 is attached to the excavating device 2 by a supporting component composed of a stepped fixed shaft 7, a rotary bearing 10, and the like. The inner peripheral side 10a of the rotating bearing 10 is the large diameter portion 7 of the fixed shaft 7.
In a, the outer circumferential side 10b is in contact with the inner wall 9a of the base metal 9, and the base metal 9 is supported so as to be able to freely rotate around the fixed shaft 7.
11 and 12 are a seal cover and a sealing material, which seal the lubricating oil holding portion of the rotary bearing 10. 14a is the seal cover mounting bolt, 14b
is the lid fixing bolt.
一方、台金９は、側面視円板状に形成され、そ
の周縁部９ｂは、中央が円周方向に張り出した断
面山形を呈しており、この中央部に超硬チツプ等
の刃体１３の埋込み用溝１５が設けられている。
この溝１５は断面が方形で、全体として側面視
（すなわち回転軸の方向から見たとき）が八角形
（Ａ−Ｂ−Ｃ−Ｄ−Ｅ−Ｆ−Ｇ−Ｈ）となつてい
る。超硬合金その他の焼結合金、セラミツクス、
硬質金属、鋼材等でつくられた８個の刃体１３，
１３，…は底面が平面で刃先部が円弧をなす扇形
に形成されており、上記八角形の各辺（Ａ−Ｂ，
Ｂ−Ｃ，…等）とその底面１３ａとが合致するよ
うに溝１５内に嵌入されろう付けされて、台金の
外周部に連続的な円形の刃先稜部を形成する。溝
１５外へ突出した刃体１３の山形の刃先部１３ｂ
は台金９の周縁部９ｂとほぼ同じ傾斜面で形成さ
れている。また、刃体１３両側の台金周縁部９ｂ
には表面硬化用の肉盛層１７が設けられている。
なお、刃体１３と台金９の境界部には肉盛層１７
が形成されておらず、刃体１３と肉盛層１７との
間にはｄの幅で溝状の台金露出部Ｄが形成されて
いる。この肉盛材としては、例えばタングステン
カーバイト系の肉盛材等ハードフエーシング用と
して通常使用される硬化肉盛材が使用される。な
お、刃体埋設用の溝１５は、図示例では全体とし
て八角形を呈するように形成されているが、六角
形、十角形等適当な多角形状に形成しておけばよ
い。また、以上の図示例では、第４図ａにも例示
するようにローラビツトが単一円板状に形成さ
れ、刃先稜部が１山となつているが、２山、３山
もしくはそれ以上の刃先稜部をそなえた複合式ロ
ーラビツトであつてもよい。 On the other hand, the base metal 9 is formed into a disk shape when viewed from the side, and its peripheral edge 9b has a chevron-shaped cross section with the center protruding in the circumferential direction. A embedding groove 15 is provided.
The groove 15 has a rectangular cross section, and as a whole has an octagonal shape (A-B-C-D-E-F-G-H) when viewed from the side (that is, when viewed from the direction of the rotation axis). Cemented carbide and other sintered alloys, ceramics,
Eight blade bodies 13 made of hard metal, steel, etc.
13,... is formed into a fan shape with a flat bottom and an arcuate cutting edge, and each side of the octagon (A-B,
B-C, . . . etc.) and the bottom surface 13a thereof are fitted into the groove 15 and brazed to form a continuous circular cutting edge ridge on the outer periphery of the base metal. The chevron-shaped cutting edge portion 13b of the blade body 13 protruding outside the groove 15
is formed of an inclined surface that is substantially the same as the peripheral edge 9b of the base metal 9. In addition, the base metal peripheral portions 9b on both sides of the blade body 13
A built-up layer 17 for surface hardening is provided.
Note that there is a built-up layer 17 at the boundary between the blade body 13 and the base metal 9.
is not formed, and a groove-shaped base metal exposed portion D with a width of d is formed between the blade body 13 and the built-up layer 17. As this overlay material, for example, a hardened overlay material commonly used for hard facings, such as a tungsten carbide overlay material, is used. Although the blade embedding groove 15 is formed to have an octagonal shape as a whole in the illustrated example, it may be formed into a suitable polygonal shape such as a hexagonal or decagonal shape. In addition, in the above illustrated example, the roller bit is formed into a single disk shape and has one ridge at the cutting edge, as illustrated in FIG. 4a, but it may have two, three or more ridges. It may also be a composite roller bit with a cutting edge ridge.
このローラビツト１は、次のような手順で製作
される。すなわち、中央部に軸支用の穴をそな
え、溝１５の切られていない円板状の台金素材を
先ず製作し、つぎに溝１５の両縁部にあたる位置
に肉盛りを行なう。このとき、溝１５の両側に約
１mm程度づつ肉盛りしない部分（ｄで示す）を残
しておく。この肉盛は、従来ガス肉盛を行なつて
いたが、加熱のため鋼材の材質が劣化するので、
表面だけの加熱ですむアーク溶接による肉盛を採
用するのが強度上好ましい。肉盛りが終つたらフ
ライス加工によつて溝１５を形成し、別に製作し
た刃体１３を銀ろう等のろう材を用いてろう付け
してローラビツト１を得る。台金９の材質として
は、例えばクロムモリブテン鋼のような鋼種を使
用し、浸炭処理を施しておくのが好ましい。 This roller bit 1 is manufactured by the following procedure. That is, a disc-shaped base metal material with a shaft support hole provided in the center and no grooves 15 cut is first manufactured, and then padding is performed at positions corresponding to both edges of the grooves 15. At this time, a portion (indicated by d) that is not built up is left on each side of the groove 15 by about 1 mm. Conventionally, gas overlay was used for this overlay, but since the quality of the steel deteriorates due to heating,
In terms of strength, it is preferable to use arc welding, which requires heating only the surface. After the build-up is completed, a groove 15 is formed by milling, and a separately manufactured blade body 13 is brazed using a brazing material such as silver solder to obtain the roller bit 1. As the material of the base metal 9, it is preferable to use a steel such as chromium molybdenum steel, and to perform a carburizing treatment.
つぎに、超硬チツプ等の刃体と台金９の境界部
に硬化肉盛層を設けない理由について説明する。 Next, the reason why a hardfacing layer is not provided at the boundary between the blade body such as a carbide tip and the base metal 9 will be explained.
第４図ａ，ｂに示すように、超硬チツプの刃体
１３を鋼製の台金の溝１５に銀ろうでろう接し、
台金に硬化肉盛層１７を３〜４mmの厚みで形成し
た試料ビツトを製作した。同図ａはｄ＝１mmの台
金露出部Ｄを形成したものであり、同図ｂはこの
ような台金露出部を形成せず、刃体１３に達する
まで肉盛層を形成したものである。なお、ｄの幅
は１〜３mmとするのが好ましい。 As shown in FIGS. 4a and 4b, the carbide tip blade 13 is soldered to the groove 15 of the steel base metal with silver solder,
A sample bit was manufactured by forming a hardfacing layer 17 with a thickness of 3 to 4 mm on the base metal. Figure a shows an example in which an exposed base metal part D of d = 1 mm is formed, and Figure b shows an example in which such an exposed base metal part is not formed and a built-up layer is formed until it reaches the blade body 13. be. Note that the width of d is preferably 1 to 3 mm.
これらのビツトについてＸ線による残留応力の
測定を行なつた結果は第１表に示す通りであつ
た。同表において、No.１，２は通常の銀ろうを用
い台金露出部Ｄを形成したものを、またビツトNo.
３，４は薄い銅板が介在するサンドイツチろう
（銀ろう）を用い、台金露出部Ｄを形成したもの
をそれぞれあらわす。また、ビツトNo.５，６は第
４図ｂに示す如く台金露出部Ｄを形成しなかつた
ものであり、ろう材としてはNo.３，４と同様なサ
ンドイツチろうを用いた。Ａ，Ｂ，Ｃは残留応力
測定個所をあらわすもので、Ａはチツプ（刃体）
先端部、Ｂはろう層に近いチツプ側の部分、Ｃは
同台金側の部分である。なお、Ｘ方向とはチツプ
の先端に向かう方向であり、Ｙ方向とはこれと直
角なビツトゲージ方向である。 The residual stress of these bits was measured using X-rays and the results are shown in Table 1. In the same table, Nos. 1 and 2 are those in which the base metal exposed part D is formed using ordinary silver solder, and Bit No.
Reference numerals 3 and 4 each represent a base metal exposed portion D formed using sand German solder (silver solder) with a thin copper plate interposed therebetween. Further, bits Nos. 5 and 6 did not have the base metal exposed portion D as shown in FIG. 4b, and the same sandwiched German solder as in Nos. 3 and 4 was used as the brazing material. A, B, and C represent the residual stress measurement points, and A is the tip (blade body).
At the tip, B is the part on the chip side near the solder layer, and C is the part on the metal side. Note that the X direction is the direction toward the tip of the chip, and the Y direction is the bit gauge direction perpendicular to this direction.
第１表からわかる通り、チツプと台金の境界部
に硬化肉盛層の形成されていないもの（No.５，
６）ではチツプと台金との残留応力の差が著しく
大きくなつているが、台金露出層を境界部に設け
たもので両者の残留応力の差が小さく押えられて
いる。チツプには使用中大きな荷重がかかるが、
このようにチツプ側と台金側の残留応力の差が小
さいほどチツプにクラツク等が発生しにくく、強
度的にすぐれたものとなることが知られているの
で、本考案におけるように、チツプと台金の境界
部に台金露出部を設けておくことがビツト強度上
きわめて重要であることがわかる。 As can be seen from Table 1, the hardfacing layer is not formed at the boundary between the chip and the base metal (No. 5,
In No. 6), the difference in residual stress between the chip and the base metal is extremely large, but the difference in residual stress between the two is kept small by providing the base metal exposed layer at the boundary. A large load is applied to the chip during use, but
It is known that the smaller the difference in residual stress between the chip side and the base metal side, the less likely cracks will occur in the chip, resulting in superior strength. It can be seen that providing an exposed portion of the base metal at the boundary between the base metals is extremely important for the strength of the bit.
このローラビツト１は、刃体ろう接用の溝１５
が、平坦な底面をもち、全体として台金の外周方
向に沿つて多角形状に形成されているので、使用
中に周方向の力を受けても刃体の位置ズレが生じ
にくい。また、溝底が平坦であるのでろう付け用
の研磨仕上げが容易である。この台金にろう付け
される刃体も、底面が平坦であるから製作が容易
であり、研磨仕上げが容易である。 This roller bit 1 has a groove 15 for soldering the blade body.
However, since it has a flat bottom surface and is formed into a polygonal shape along the outer circumferential direction of the base metal as a whole, the blade body is unlikely to shift position even if it receives force in the circumferential direction during use. Furthermore, since the groove bottom is flat, polishing for brazing is easy. The blade body to be brazed to this base metal also has a flat bottom surface, so it is easy to manufacture and easy to polish.
さらに、ビツト頭部の台金の部分に硬化肉盛層
が形成されているので、台金の摩耗が防止され、
長時間にわたつて使用することができる。しか
も、上記肉盛層は刃体と台金の境界部には形成さ
れていないので、刃体と台金の残留応力の差が小
さく、強度的にすぐれたものとなつている。 Furthermore, since a hardened build-up layer is formed on the base metal part of the bit head, wear of the base metal is prevented.
Can be used for a long time. Moreover, since the build-up layer is not formed at the boundary between the blade and the base metal, the difference in residual stress between the blade and the base metal is small, resulting in excellent strength.
［考案の効果］
以上の説明から明らかなように、本考案にかか
る切削ビツトは、台金頭部の摩耗が少なく強度的
にすぐれたものとなつた。上記説明ではローラビ
ツトを例にとつて説明したが、チゼル形、ボタン
形等各種のビツトに応用することができることは
明らかである。[Effects of the invention] As is clear from the above explanation, the cutting bit according to the invention has less wear on the base metal head and is superior in strength. Although the above description has been made using a roller bit as an example, it is clear that the present invention can be applied to various types of bits such as chisel-shaped and button-shaped bits.
第１図は本考案にかかるローラビツトの使用状
態の説明図、第２図および第３図は要部の一部断
面正面図および側面図、第４図ａ，ｂはビツト頭
Fig. 1 is an explanatory diagram of the roller bit according to the present invention in use, Figs. 2 and 3 are a partially sectional front view and side view of the main parts, and Figs. 4 a and b are the bit head.
Claims (1)
う材で固着してなる切削ビツトであつて、前記台
金の頭部に硬化肉盛層を形成するとともに、台金
の溝に植設された前記硬質刃体と台金の境界部に
は、硬化肉盛層が形成されていない細幅の台金露
出部を設けたことを特徴とする切削ビツト。 A cutting bit in which a hard blade is fixed with a brazing material to a groove formed in the head of a steel base metal, and a hardfacing layer is formed on the head of the base metal, and the groove of the base metal is A cutting bit characterized in that a narrow base metal exposed portion in which a hardfacing layer is not formed is provided at the boundary between the hard blade body and the base metal implanted in the base metal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1985197168U JPS6323507Y2 (en) | 1985-12-21 | 1985-12-21 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1985197168U JPS6323507Y2 (en) | 1985-12-21 | 1985-12-21 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61169191U JPS61169191U (en) | 1986-10-20 |
| JPS6323507Y2 true JPS6323507Y2 (en) | 1988-06-28 |
Family
ID=30755266
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1985197168U Expired JPS6323507Y2 (en) | 1985-12-21 | 1985-12-21 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6323507Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6532434B2 (en) * | 2016-08-03 | 2019-06-19 | 株式会社奥村組 | Excavator roller cutter and excavator including the same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59173478A (en) * | 1983-03-18 | 1984-10-01 | 株式会社 利根ボ−リング | Bit for excavation and manufacture thereof |
-
1985
- 1985-12-21 JP JP1985197168U patent/JPS6323507Y2/ja not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59173478A (en) * | 1983-03-18 | 1984-10-01 | 株式会社 利根ボ−リング | Bit for excavation and manufacture thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61169191U (en) | 1986-10-20 |
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