JP5458442B2

JP5458442B2 - Mowing rotary blade

Info

Publication number: JP5458442B2
Application number: JP2010144245A
Authority: JP
Inventors: 仁彦浅田
Original assignee: 株式会社トリガー
Priority date: 2010-06-08
Filing date: 2010-06-08
Publication date: 2014-04-02
Anticipated expiration: 2030-06-08
Also published as: JP2011254793A

Description

本発明は、刈払い機に装着されて雑草や雑木（雑木等という）を刈払いする際に使用される刈払い用回転刃に関する。 The present invention relates to a rotary blade for brush cutting that is attached to a brush cutter and used when cutting weeds and trees (referred to as trees).

従来、刈払い用の回転刃としては、例えば図９に示すものが知られている。この回転刃１０１は、円板状の台金１０２の中心部分の平坦部１０２ａに刈払い機１０５への取付孔１０３が形成されると共に、平坦部１０２ａの外側周囲に、裏面側に膨らんだ円環状の膨出部１０２ｂが形成されている。また、台金１０２の膨出部１０２ｂの外側には、刃先部１０２ｃが前記平坦部１０２ａ方向に反った状態で形成され、刃先部１０２ｃの先端に設けた図示しないチップ固着部に超硬合金からなるチップがロー付けされている。なお、台金の外周縁にチップがロー付けされた刈払い用回転刃としては、例えば特許文献１がある。 Conventionally, as a rotary blade for brush cutting, for example, the one shown in FIG. 9 is known. In the rotary blade 101, a mounting hole 103 for a brush cutter 105 is formed in a flat portion 102a at the center of a disk-shaped base metal 102, and a circular bulge is formed on the back surface around the outside of the flat portion 102a. An annular bulge portion 102b is formed. Further, a blade edge portion 102c is formed outside the bulging portion 102b of the base metal 102 in a state of warping in the direction of the flat portion 102a, and a chip fixing portion (not shown) provided at the tip of the blade edge portion 102c is made of cemented carbide. The chip that becomes is brazed. For example, Patent Document 1 discloses a rotary blade for brush cutting in which a chip is brazed to the outer peripheral edge of a base metal.

実開平０６−２４４２９号公報Japanese Utility Model Publication No. 06-24429

しかしながら、このような回転刃１０１にあっては、膨出部１０２ｂの内側の凹部１０４内に刈払い機１０５への取付ボルト１０６を位置させることができて、取付ボルト１０６の頭部の外部への露出を防止してその摩耗や変形等を防止できるという利点が得られるものの、台金１０２の刃先部１０２ｃにロー付けされるチップ（刃先）による、雑木等の切断性能が劣るという問題点を有している。 However, in such a rotary blade 101, the mounting bolt 106 to the brush cutter 105 can be positioned in the recess 104 inside the bulging portion 102b, and the head of the mounting bolt 106 can be moved to the outside. Although the advantage that the wear and deformation of the metal plate 102 can be prevented and the wear and deformation thereof can be prevented is obtained, the cutting performance of miscellaneous trees and the like by the chip (blade tip) brazed to the blade tip portion 102c of the base metal 102 is inferior. Have.

すなわち、前記回転刃１０１の場合、台金１０２の刃先部１０２ｃにチップをロー付けした後に、プレス（絞り）加工により膨出部１０２ｂを成形する製造方法が採用されていることから、台金１０２のスプリングバック等により台金１０２の膨出部１０２ｂの外側が図９で上方に反った状態となる。その結果、刃先であるチップの突出方向が台金１０２の平坦部１０２ａに対して角度を持ち平坦部１０２ａと略同一面とならず、刃先が雑木等に直角に入り難くなって、良好な切れ味を得ることが難しい。 That is, in the case of the rotary blade 101, since the manufacturing method of forming the bulging portion 102b by press (drawing) processing after the chip is brazed to the cutting edge portion 102c of the base metal 102 is adopted. The outer side of the bulging portion 102b of the base metal 102 is warped upward in FIG. As a result, the protruding direction of the tip, which is the cutting edge, is at an angle with respect to the flat portion 102a of the base metal 102 and is not substantially flush with the flat portion 102a, and the cutting edge is difficult to enter at right angles to miscellaneous trees, etc. Difficult to get.

また、前記回転刃１０１の場合、台金１０２の地面と接触する裏面側に膨出部１０２ｂが円環状に形成されているため、回転刃１０１の使用により膨出部１０２ｂの裏面が地面に長時間接触すると、該膨出部１０２ｂの底部が摩耗し、台金１０２の刃先部１０２ｃが膨出部１０２ｂ部分において平坦部１０２ａから分離（分断）する虞がある。さらに、回転刃１０１を使用した雑木等の刈払い作業においては、作業者が雑木等の根本を狙うため、刃先であるチップが小石等の下側に入り込み易く、小石等を上方に跳ね飛ばしたり、あるいはチップが破損する場合がある等、刈払い作業中に作業者が思わぬ人身事故に巻き込まれる虞もある。 Further, in the case of the rotary blade 101, since the bulging portion 102b is formed in an annular shape on the back side of the base metal 102 that contacts the ground, the use of the rotary blade 101 causes the back surface of the bulging portion 102b to be long on the ground. When contact is made for a time, the bottom of the bulging portion 102b may be worn, and the cutting edge portion 102c of the base metal 102 may be separated (divided) from the flat portion 102a at the bulging portion 102b. Furthermore, in the cutting work of miscellaneous trees and the like using the rotary blade 101, since the operator aims at the root of the miscellaneous trees and the like, the tip that is the blade tip easily enters the lower side of the pebbles, etc. There is also a possibility that the operator may be involved in an unexpected accident during the mowing operation, such as a chip being damaged.

本発明は、このような事情に鑑みてなされたもので、その目的は、チップを雑木等に直角に入れることができて良好な切れ味が容易に得られると共に、刃先平坦部の取付平坦部に対する分離を防止しつつ小石等の上方への跳ね飛ばしを抑えることが可能で安全性に優れた刈払い用回転刃を提供することにある。 The present invention has been made in view of such circumstances, and the object thereof is to insert a chip into a miscellaneous tree or the like at right angles so that a good sharpness can be easily obtained, and the cutting edge flat portion is attached to the mounting flat portion. An object of the present invention is to provide a rotary blade for mowing that is excellent in safety and capable of suppressing upward splashing of pebbles and the like while preventing separation.

かかる目的を達成すべく、本発明のうち請求項１に記載の発明は、円板状の台金の外周縁に刃先を有する刈払い用回転刃において、前記台金は、その中心部分に刈払い機への取付孔が形成された取付平坦部と、該取付平坦部の外側に反刈払い機側である台金の裏面側に突出する状態で形成された円環状の膨出部と、該膨出部の外側に台金の外周縁方向に向けて前記取付平坦部と略同一面状に延設された刃先平坦部とを備え、前記膨出部の高さが、前記取付平坦部を刈払い機に取付ボルトで取り付けた際に、該取付ボルトの突出寸法より大きく設定されると共に、該膨出部の円周方向の所定位置に、膨出部が摩耗した場合でも前記刃先平坦部と取付平坦部の連結を維持可能な連結維持部が複数設けられ、該連結維持部は、前記膨出部の底部を台金の取付平坦部側に凹ませることで設けた凹部であると共に、該凹部の底部は、前記刃先平坦部に対する寸法を取付平坦部側が大きく刃先平坦部側が小さく設定することにより傾斜していることを特徴とする。In order to achieve this object, the invention according to claim 1 of the present invention is a rotary blade for brush cutting having a cutting edge on the outer peripheral edge of a disk-shaped base metal, wherein the base metal is cut at the central portion thereof. An attachment flat part in which an attachment hole to the dispenser is formed, and an annular bulging part formed in a state protruding from the back side of the base metal on the anti-trimmer side on the outside of the attachment flat part; A blade edge flat portion extending substantially in the same plane as the mounting flat portion toward the outer peripheral edge of the base metal on the outer side of the bulging portion, and the height of the bulging portion is the mounting flat portion Is set to be larger than the projecting dimension of the mounting bolt, and the cutting edge is flat even when the bulging portion is worn at a predetermined position in the circumferential direction of the bulging portion. connection maintaining unit capable of maintaining the connection parts and mounting flat portion provided with a plurality, the connecting maintenance unit base bottom of the bulging portion With a recess formed by recessing the the mounting flat side, bottom of the recess is, that it is inclined by attaching flat side dimensions is large cutting flat portion is set small with respect to the cutting edge flat portion Features.

また、請求項２に記載の発明は、前記膨出部が、その地面と接触する刃先平坦部側の側壁の傾斜角度が２０〜４５度に設定されていることを特徴とする。The invention according to claim 2 is characterized in that an inclination angle of the side wall on the blade edge flat part side where the bulging part comes into contact with the ground is set to 20 to 45 degrees.

本発明のうち請求項１に記載の発明によれば、刃先を有する刃先平坦部が刈払い機に取り付けられる取付平坦部と略同一面状に形成されていることから、刃先を雑木等に直角に入れることができて回転刃に良好な切れ味を維持しつつ、膨出部の円周方向の所定位置に連結維持部が複数設けられているため、膨出部が摩耗した場合であっても連結維持部で刃先平坦部の取付平坦部からの分離を防止できると共に、膨出部を先に地面に接触させることができて、刃先が小石等の下に入り込むのを抑制して小石等の上方への跳ね飛ばしを防止できる等、刈払い作業の安全性を高めることができる。 According to the first aspect of the present invention, the cutting edge flat portion having the cutting edge is formed in substantially the same plane as the mounting flat portion attached to the brush cutter, so that the cutting edge is perpendicular to the miscellaneous tree or the like. Even if the bulging part is worn out, a plurality of connection maintaining parts are provided at predetermined positions in the circumferential direction of the bulging part while maintaining a good sharpness in the rotary blade. The connection maintaining part can prevent the blade edge flat part from being separated from the mounting flat part, and the bulge part can be brought into contact with the ground first, and the blade edge can be prevented from entering under the pebbles, etc. It is possible to improve the safety of the brushing work, such as preventing upward splashing.

また、連結維持部が膨出部の底部を台金の取付平坦部側に凹ませることで設けた凹部であるため、連結維持部を簡単に形成して安価な回転刃を得ることができると共に、凹部形状でリブとしても機能する連結維持部により膨出部自体の剛性を高めることができる。 Moreover, since the connection maintaining part is a recess provided by denting the bottom part of the bulging part to the mounting flat part side of the base metal, the connection maintaining part can be easily formed and an inexpensive rotary blade can be obtained. The rigidity of the bulging portion itself can be increased by the connection maintaining portion that also functions as a rib in the concave shape.

さらに、凹部の底部が、刃先平坦部に対する寸法を取付平坦部側が大きく刃先平坦部側が小さく設定することにより傾斜しているため、連結維持部を平面視で略楕円形状の異形形状として、該維持部や膨出部の剛性を一層高めることができる。 Furthermore, since the bottom of the concave portion is inclined by setting the dimension with respect to the blade edge flat portion to be larger on the attachment flat portion side and smaller on the blade edge flat portion side, the connection maintaining portion is changed to a substantially elliptical deformed shape in plan view. The rigidity of the part and the bulging part can be further increased.

また、請求項２に記載の発明によれば、請求項１に記載の発明の効果に加え、膨出部の地面と接触する刃先平坦部側の側壁の傾斜角度が２０〜４５度に設定されているため、刈払い作業時の回転刃の回転に対する地面から受ける抵抗を小さくすることができて、刈払い作業の能率向上を図ることができる。 According to the invention described in claim 2, in addition to the effect of the invention described in claim 1 , the inclination angle of the side wall on the blade edge flat part side that contacts the ground of the bulging part is set to 20 to 45 degrees. Therefore, the resistance received from the ground against the rotation of the rotary blade during the brushing operation can be reduced, and the efficiency of the brushing operation can be improved.

本発明に係わる刈払い用回転刃の一実施形態を示す平面図 The top view which shows one Embodiment of the rotary blade for brushing concerning this invention 同図１のＡ−Ａ線に沿った矢視図 Arrow view taken along line AA in FIG. 同図１のＢ−Ｂ線に沿った矢視図 Arrow view taken along line BB in FIG. 同連結維持部の斜視図 Perspective view of the connection maintaining part 同刃先の説明図 Illustration of the cutting edge 同刈払い機への取付状態を示す図 The figure which shows the attachment state to the same brush cutter 同回転刃の変形例を示す図６と同様の図 The same figure as FIG. 6 which shows the modification of the rotary blade 同回転刃の他の変形例を示す図 The figure which shows the other modification of the rotary blade 従来の回転刃を示す図 Diagram showing a conventional rotary blade

以下、本発明を実施するための形態を図面に基づいて詳細に説明する。
図１〜図６は、本発明に係わる刈払い用回転刃の一実施形態を示している。図１〜図３に示すように、刈払い用回転刃１（回転刃１という）は、円板状の台金２を有し、この台金２の中心位置には、後述する刈払い機５への取付孔３が形成されている。DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
1 to 6 show an embodiment of a rotary blade for brush cutting according to the present invention. As shown in FIG. 1 to FIG. 3, the brush cutting rotary blade 1 (referred to as the rotary blade 1) has a disk-shaped base metal 2, and a brush cutter, which will be described later, is provided at the center of the base metal 2. A mounting hole 3 to 5 is formed.

また、台金２は、取付孔３の外側に所定幅の取付平坦部２ａが形成され、この取付平坦部２ａの外側に反刈払い機５側に向けて高さ寸法ｈ突出した膨出部２ｂが形成されると共に、この膨出部２ｂの外側に刃先平坦部２ｃが形成されている。そして、台金２には、前記膨出部２ｂによりその内側に裏面視円形の空間状の窪み部４が形成されると共に、取付平坦部２ａと刃先平坦部２ｃとが同一面状に形成されることにより、刃先としての後述するチップ６と取付平坦部２ａとが同一面状に位置するようになっている。 Further, the base metal 2 is formed with a mounting flat portion 2a having a predetermined width outside the mounting hole 3, and a bulging portion protruding outside the mounting flat portion 2a toward the counter-trimmer 5 side by a height dimension h. 2b is formed, and a blade edge flat portion 2c is formed outside the bulging portion 2b. The base metal 2 is formed with a hollow portion 4 having a circular shape when viewed from the back by the bulging portion 2b, and the mounting flat portion 2a and the blade edge flat portion 2c are formed on the same surface. Thus, a later-described tip 6 as a cutting edge and the mounting flat portion 2a are positioned on the same plane.

また、前記膨出部２ｂは、前記取付平坦部２ａと刃先平坦部２ｃ間に、一対の側壁２ｂ１、２ｂ２を有して底部２ｂ３が円弧状に形成されて、例えば高さ寸法ｈ＝１６ｍｍを有する円環状の凹部で形成されている。このとき、左右の側壁２ｂ１、２ｂ２の傾斜角度α１、α２は、α１＝α２＝略４５度に設定され、また、側壁２ｂ１側の底部２ｂ３のアールが例えば８．３ｍｍ程度で、側壁２ｂ２側の底部２ｂ３のアールが例えば９．５ｍｍ程度となるように設定されている。 Further, the bulging portion 2b has a pair of side walls 2b1 and 2b2 between the mounting flat portion 2a and the blade edge flat portion 2c, and the bottom portion 2b3 is formed in an arc shape. For example, the height dimension h = 16 mm. It is formed by an annular recess having the same. At this time, the inclination angles α1 and α2 of the left and right side walls 2b1 and 2b2 are set to α1 = α2 = approximately 45 degrees, and the radius of the bottom 2b3 on the side wall 2b1 side is about 8.3 mm, for example. For example, the radius of the bottom 2b3 is set to be about 9.5 mm.

さらに、前記膨出部２ｂの円周方向の一定間隔位置には、複数個（図では６個）の連結維持部７が一体形成されている。この連結維持部７は、図４に示すように、膨出部２ｂの底部２ｂ３を台金２の取付平坦部２ａ（刃先平坦部２ｃ）側に、所定寸法凹ませることにより形成されている。このとき、連結維持部７の底部７ａは、図３に示すように、取付平坦部２ａとの寸法ｈ２が、刃先平坦部２ｃとの寸法ｈ１に対して大きく（ｈ１＜ｈ２）設定されることにより、底部７ａが台金２の外周縁側が高くなるように傾斜している。これにより、連結維持部７を台金２の表面側から見た場合に、その形状が略楕円形状の異形形状となるように設定されている。この膨出部２ｂにより、刈払い作業時にチップ６より先に地面に接触可能になると共に、連結維持部７により刃先平坦部２ｃの取付平坦部２ａからの分離・分断が防止されるようになっている。 Further, a plurality (six in the figure) of connection maintaining portions 7 are integrally formed at a constant interval position in the circumferential direction of the bulging portion 2b. As shown in FIG. 4, the connection maintaining part 7 is formed by denting the bottom part 2 b 3 of the bulging part 2 b toward the mounting flat part 2 a (blade edge flat part 2 c) side of the base metal 2 by a predetermined dimension. At this time, as shown in FIG. 3, the bottom portion 7a of the connection maintaining portion 7 is set such that the dimension h2 with the mounting flat portion 2a is larger than the dimension h1 with the blade edge flat portion 2c (h1 <h2). Thus, the bottom portion 7a is inclined so that the outer peripheral edge side of the base metal 2 becomes higher. Thereby, when the connection maintenance part 7 is seen from the surface side of the base metal 2, the shape is set so as to be a substantially elliptical irregular shape. The swollen portion 2b allows contact with the ground prior to the tip 6 during the brushing operation, and the connection maintaining portion 7 prevents separation and division of the blade edge flat portion 2c from the mounting flat portion 2a. ing.

なお、前記台金２の外周縁である刃先平坦部２ｃ先端には、刃室（ガレット）８とチップ固着部９（図１参照）が一定間隔で多数形成され、各チップ固着部９には、超硬合金からなる前記チップ６がロー付けされている。このとき、チップ６は、図５に示すように、掬い面６ａと先端面６ｂ及び４つの固着面６ｃ〜６ｆを有する如く形成されると共に、３つの固着面６ｃ〜６ｅの厚さ方向の両側に鍔６ｇが側面視で略Ｌ字形状にそれぞれ形成されている。また、このチップ６の各固着面６ｃ〜６ｆの形状に対応して、前記チップ固着部９は窪んだ溝状に形成されている。 A large number of blade chambers (gallets) 8 and tip fixing portions 9 (see FIG. 1) are formed at regular intervals at the tip of the blade edge flat portion 2c, which is the outer peripheral edge of the base metal 2. The tip 6 made of cemented carbide is brazed. At this time, as shown in FIG. 5, the chip 6 is formed to have a scooping surface 6a, a tip surface 6b, and four fixing surfaces 6c to 6f, and both sides of the three fixing surfaces 6c to 6e in the thickness direction. In addition, the flange 6g is formed in a substantially L shape in a side view. Further, the chip fixing part 9 is formed in a recessed groove shape corresponding to the shape of each fixing surface 6c to 6f of the chip 6.

そして、前記チップ６は、台金２のチップ固着部９に、図５（ａ）の矢印イ方向から差し込むことにより、チップ６の一対の鍔６ｇ間に台金２が挟まれた状態となり、この状態で、４つの固着面６ｃ〜６ｆとチップ固着部９、及び一対の鍔６ｇの内面と台金２の図５（ｂ）に示す両側面２ｄがそれぞれロー付けされる。これにより、チップ６のチップ固着部９に対するロー付け面積が大幅に拡大することになる。なお、台金２のチップ固着部９に固着されたチップ６は、鍔６ｇの部分が台金２の両側面２ｄから所定寸法突出して、この寸法があさり寸法となっている。 And the said chip | tip 6 will be in the state by which the base metal 2 was pinched | interposed into the chip | tip fixing | fixed part 9 of the base metal 2 from the arrow (a) direction of FIG. In this state, the four fixing surfaces 6c to 6f, the chip fixing portion 9, the inner surfaces of the pair of flanges 6g, and both side surfaces 2d of the base metal 2 shown in FIG. As a result, the brazing area of the chip 6 with respect to the chip fixing portion 9 is greatly increased. Note that the chip 6 fixed to the chip fixing portion 9 of the base metal 2 protrudes from the both side surfaces 2d of the base metal 2 by a predetermined dimension, and this dimension is a simple dimension.

このように構成された回転刃１は、次のようにして製造される。すなわち、先ず、台金素材（炭素鋼板等の生材）をプレスの絞り加工により加工して、取付孔３を有する前記取付平坦部２ａと、連結維持部７を有する膨出部２ｂと、刃室８、チップ固着部９、図示ししない軽量孔等を有する刃先平坦部２ｃを成形する。この絞り加工時に、前記膨出部２ｂの取付平坦部２ａや刃先平坦部２ｂに対するアールを例えば４〜７ｍｍ程度に設定したり、膨出部２ｂの底部２ｂ３のアールを前述したように設定することにより、炭素鋼板等からなる台金素材を絞り加工しても、膨出部６部分の割れ等が防止されるようになっている。なお、連結維持部７は、絞り加工時の一体成形に限らず、後加工とすることも勿論可能である。 The rotary blade 1 configured as described above is manufactured as follows. That is, first, a base metal material (raw material such as a carbon steel plate) is processed by drawing with a press, the mounting flat portion 2a having the mounting hole 3, the bulging portion 2b having the connection maintaining portion 7, and the blade The blade 8 flat part 2c having the chamber 8, the tip fixing part 9, the light-weight hole (not shown) and the like is formed. At the time of this drawing process, the radius of the bulging portion 2b with respect to the mounting flat portion 2a and the blade edge flat portion 2b is set to about 4 to 7 mm, for example, or the radius of the bottom portion 2b3 of the bulging portion 2b is set as described above. Thus, even if a base metal material made of a carbon steel plate or the like is drawn, cracking or the like of the bulging portion 6 is prevented. The connection maintaining unit 7 is not limited to integral molding at the time of drawing, but can of course be post-processed.

そして、台金素材を加工して台金２を作成したら、この台金２を例えば高周波の誘導加熱を利用して焼入れすると共に焼き鈍しする熱処理を行う。この熱処理時に、台金２を加熱加圧状態で行うことにより、取付平坦部２ａと刃先平坦部２ｃの反り等が防止されて、互いに同一面状の取付平坦部２ａと刃先平坦部２ｃが成形される。台金２の熱処理が終了したら、例えばショットブラスト処理による表面処理を行ったり、台金２の各チップ固着部９にチップ６を例えば高周波の誘導加熱を利用してロー付けする。 And if the base metal material is processed and the base metal 2 is produced, this base metal 2 will be hardened and annealed using high frequency induction heating, for example. During this heat treatment, the base metal 2 is heated and pressed to prevent warping of the mounting flat portion 2a and the blade edge flat portion 2c, and the mounting flat portion 2a and the blade edge flat portion 2c having the same surface are formed. Is done. When the heat treatment of the base metal 2 is completed, for example, a surface treatment by shot blasting is performed, or the chip 6 is brazed to each chip fixing portion 9 of the base metal 2 using, for example, high-frequency induction heating.

そして、チップ６の掬い面６ａ、先端面６ｂ及び両側面等の研磨を行い仕上げ処理することにより、回転刃１が製造される。つまり、前記回転刃１の場合、チップ６がロー付けされる前の台金２を、加熱加圧状態で熱処理することにより、取付平坦部２ａや刃先平坦部２ｃがスプリングバックで反ることを防止できて、同一面状の取付平坦部２ａと刃先平坦部２ｃとを容易に得ることが可能となる。 And the rotary blade 1 is manufactured by grind | polishing and finishing the scooping surface 6a of the chip | tip 6, the front end surface 6b, and both side surfaces. That is, in the case of the rotary blade 1, the mounting flat part 2 a and the blade edge flat part 2 c are warped by the spring back by heat-treating the base metal 2 before the tip 6 is brazed in a heated and pressurized state. Therefore, it is possible to easily obtain the attachment flat portion 2a and the blade edge flat portion 2c having the same surface.

このように構成された回転刃１は、図６に示すように、刈払い機５の回転伝達シャフト５ａ先端の鋸受けフランジ５ｂに、鋸押えフランジ５ｃ及び取付ボルト１０等を介して取り付けられる。この取付時に、回転刃１の取付平坦部２ａの反膨出部２ｂ側の面（表面）を鋸受けフランジ５ｂの面に当接させることにより、回転刃１の窪み部４内に取付ボルト１０が位置した状態となり、その際、膨出部２ｂの高さ寸法ｈにより、取付ボルト１０の頭部が窪み部４内に位置して外側（図５において下方）に突出しないようになっている。 As shown in FIG. 6, the rotary blade 1 configured in this way is attached to the saw receiving flange 5 b at the tip of the rotation transmission shaft 5 a of the brush cutter 5 via a saw retainer flange 5 c and a mounting bolt 10. At the time of this mounting, the surface (surface) of the mounting flat portion 2a of the rotary blade 1 on the side opposite to the bulging portion 2b is brought into contact with the surface of the saw receiving flange 5b, thereby mounting the mounting bolt 10 in the recess 4 of the rotary blade 1. In this case, due to the height dimension h of the bulging portion 2b, the head of the mounting bolt 10 is positioned in the hollow portion 4 so as not to protrude outward (downward in FIG. 5). .

なお、回転刃１の取付平坦部２ａの幅（有効平坦部幅）は、刈払い機５の鋸受けフランジ５ｂの外径より所定寸法大きく設定されており、取付平坦部２ａが鋸受けフランジ５ｂのフランジ面の全域に密着した状態となっている。この取付状態で、刈払い機５を作動させることにより回転刃１が回転すると、取付平坦部２ａと同一面状に位置する刃先平坦部２ｃ先端のチップ６が、雑木等に略直角に入る状態となって、雑木等がスムーズに切断されることになる。 The width of the mounting flat portion 2a (effective flat portion width) of the rotary blade 1 is set to be a predetermined dimension larger than the outer diameter of the saw receiving flange 5b of the brush cutter 5, and the mounting flat portion 2a is set to the saw receiving flange 5b. It is in a state of being in close contact with the entire area of the flange surface. When the rotary blade 1 is rotated by operating the brush cutter 5 in this mounted state, the tip 6 at the tip of the blade flat portion 2c located on the same plane as the mounting flat portion 2a enters a substantially right angle with a miscellaneous tree or the like. Thus, miscellaneous trees and the like are cut smoothly.

図７及び図８は、本発明に係わる回転刃１の変形例を示している。図７に示す回転刃１は、膨出部２ｂの側壁２ｂ１の傾斜角度をα１＝３３度、側壁２ｂ２の傾斜角度をα２＝４５度として、地面と接触する側壁２ｂ１の傾斜角度α１を小さく設定したものである。この傾斜角度α１は、刈払い作業時の回転刃１の地面からの抵抗をあまり受けない２０度〜４５度の範囲に設定することが好ましいことが実験的に確認されている。 7 and 8 show a modification of the rotary blade 1 according to the present invention. In the rotary blade 1 shown in FIG. 7, the inclination angle of the side wall 2b1 of the bulging portion 2b is set to α1 = 33 degrees, the inclination angle of the side wall 2b2 is set to α2 = 45 degrees, and the inclination angle α1 of the side wall 2b1 in contact with the ground is set small. It is a thing. It has been experimentally confirmed that the inclination angle α1 is preferably set in a range of 20 degrees to 45 degrees that does not receive much resistance from the ground of the rotary blade 1 during the brushing operation.

また、図８に示す回転刃１は、前記回転刃１の取付平坦部２ａ上に、巻付き防止カップ１１を複数のリベット１２により一体的に固着したものである。すなわち、巻付き防止カップ１１は、平面視円環状の垂直壁１１ａと傾斜壁１１ｂ、及び傾斜壁１１ｂの下端に連接された底壁１１ｃ等を有し、底壁１１ｃの中心位置には、回転刃１を刈払い機５に取り付ける際に邪魔とならない円形の開口１１ｄが形成されている。また、垂直壁１２ａの上端には安全性及び巻付き防止カップの剛性アップのための返し１１ｅが設けられ、また、垂直壁１１ａや傾斜壁１１ｂの所定位置には、図示しない軽量孔や水や切り屑等を遠心力で外部に排出可能な排出孔が形成されている。この巻付き防止カップ１１により、回転刃１で刈払いされた雑木等の刈払い機５先端への巻付きが防止されるようになっている。 Further, the rotary blade 1 shown in FIG. 8 is obtained by integrally fixing a winding prevention cup 11 with a plurality of rivets 12 on the mounting flat portion 2 a of the rotary blade 1. That is, the winding prevention cup 11 includes a vertical wall 11a and an inclined wall 11b that are annular in a plan view, a bottom wall 11c that is connected to a lower end of the inclined wall 11b, and the like. A circular opening 11d that does not interfere with the attachment of the blade 1 to the brush cutter 5 is formed. Further, a barb 11e is provided at the upper end of the vertical wall 12a for improving safety and rigidity of the anti-wrapping cup, and a light hole or water (not shown) is provided at a predetermined position of the vertical wall 11a or the inclined wall 11b. A discharge hole is formed through which chips and the like can be discharged to the outside by centrifugal force. The winding prevention cup 11 prevents the winding of the miscellaneous tree or the like cut away by the rotary blade 1 around the tip of the brush cutter 5.

このように、前記回転刃１によれば、台金２の取付平坦部２ａと刃先平坦部２ｃ間に形成される膨出部２ｂの円周方向の所定位置に、連結維持部７が６個設けられているため、膨出部２ｂが地面に接触して摩耗した場合であっても、地面に接触しない連結維持部７で刃先平坦部２ｃの取付平坦部２ａからの分離・分断を防止することができる。また、刈払い作業時に、刃先としてのチップ６より膨出部２ｂを先に地面に接触させることができて、チップ６が小石等の下に入り込みのを抑制して、小石等の上方への跳ね飛ばしを防止することができ、これらにより、刈払い作業の安全性を高めることができる。 As described above, according to the rotary blade 1, six connection maintaining portions 7 are provided at predetermined positions in the circumferential direction of the bulging portion 2b formed between the mounting flat portion 2a of the base metal 2 and the blade edge flat portion 2c. Since it is provided, even when the bulging portion 2b is in contact with the ground and wears, the connection maintaining portion 7 that does not contact the ground prevents separation and division of the blade edge flat portion 2c from the mounting flat portion 2a. be able to. Further, the bulging portion 2b can be brought into contact with the ground earlier than the tip 6 as the cutting edge during the cutting operation, and the tip 6 is prevented from entering under the pebbles and the like, and the pebbles and the like are moved upward. Splashing can be prevented, and the safety of the brushing work can be enhanced by these.

また、連結維持部７が膨出部２ｂの底部２ｂ３を台金２の取付平坦部２ａ側に凹ませることで設けた凹部であるため、例えば同時成形や後加工で連結維持部７を簡単に形成することができ、安価な回転刃１を得ることができると共に、凹部形状の連結維持部７がリブとして機能して膨出部２ｂの剛性を高めることができる。特に、連結維持部７の底部７ａが、刃先平坦部２ｃ側の寸法ｈ１が取付平坦部２ａの寸法ｈ２がより小さくなる如く傾斜しているため、連結維持部７を平面視で略楕円形状の異形形状として、連結維持部７や膨出部２ｂの剛性を一層高めることができる。その結果、台金２自体の剛性を高めて、例えば刈払い作業時の台金２の振れやあおりを抑制することができる。 Moreover, since the connection maintenance part 7 is a recessed part provided by denting the bottom part 2b3 of the bulging part 2b to the mounting flat part 2a side of the base metal 2, the connection maintenance part 7 can be easily formed by, for example, simultaneous molding or post-processing. It is possible to form an inexpensive rotary blade 1, and the concave connection maintaining portion 7 functions as a rib to increase the rigidity of the bulging portion 2b. In particular, the bottom 7a of the connection maintaining portion 7 is inclined so that the dimension h1 on the blade edge flat portion 2c side is smaller than the dimension h2 of the mounting flat portion 2a. As an irregular shape, the rigidity of the connection maintaining portion 7 and the bulging portion 2b can be further increased. As a result, it is possible to increase the rigidity of the base metal 2 itself, and to suppress, for example, the swinging and tilting of the base metal 2 at the time of brushing work.

さらに、膨出部２の地面と接触する側壁２ｂ１の傾斜角度α１が２０〜４５度に設定されているため、刈払い作業時の回転刃１の回転に対する地面から受ける抵抗を小さくすることができて、刈払い作業の能率向上を図ることができる。また、台金２が取付平坦部２ａと膨出部２ｂ及び刃先平坦部２ｃとを備え、膨出部２ｂの高さ寸法ｈが取付平坦部２ａを刈払い機５に取付ボルト１０で取り付けた際に、該取付ボルト１０の突出寸法より大きく設定されているため、膨出部２ｂによる窪み部４で取付ボルト１０を保護して頭部の摩耗や変形を抑制でき、回転刃１の刈払い機５に対する取り付けや取り外し時に、取付ボルト１０を良好に回転操作できて、回転刃１の交換作業をスムーズに行うことができる。 Furthermore, since the inclination angle α1 of the side wall 2b1 that contacts the ground surface of the bulging portion 2 is set to 20 to 45 degrees, it is possible to reduce the resistance received from the ground against the rotation of the rotary blade 1 during the brushing operation. Thus, the efficiency of the mowing work can be improved. Further, the base metal 2 is provided with a mounting flat portion 2a, a bulging portion 2b, and a blade edge flat portion 2c, and the height h of the bulging portion 2b is attached to the brush cutter 5 with mounting bolts 10. At this time, since it is set to be larger than the projecting dimension of the mounting bolt 10, the mounting bolt 10 can be protected by the recess 4 by the bulging portion 2 b, and wear and deformation of the head can be suppressed. When attaching to or detaching from the machine 5, the mounting bolt 10 can be rotated favorably, and the replacement work of the rotary blade 1 can be performed smoothly.

また、切断性能に影響する刃先平坦部２ｃが取付平坦部２ａと同一面状に形成されているため、従来のように刃先としてのチップ６と取付平坦部２ａ（刈払い機５への取付面）とが角度をもって、チップ６が雑木等に斜めに入ることを防止でき、チップ６を雑木等に略直角に入れることができて、回転刃１に良好な切れ味を容易に得ることができる。また、回転刃１に巻付き防止カップ１１を一体化すれば、刈払いされた雑木等の刈払い機５先端への巻付きを防止できて、刈払い作業の能率を一層向上させることもできる。 Further, since the cutting edge flat portion 2c that affects the cutting performance is formed on the same surface as the mounting flat portion 2a, the tip 6 as the cutting edge and the mounting flat portion 2a (the mounting surface to the brush cutter 5) as in the past. ) Can be prevented from entering the miscellaneous tree or the like obliquely, and the chip 6 can be inserted into the miscellaneous tree or the like at a substantially right angle, and a good sharpness can be easily obtained in the rotary blade 1. Moreover, if the winding prevention cup 11 is integrated with the rotary blade 1, it is possible to prevent winding of the mowed tree or the like around the tip of the brush cutter 5 and to further improve the efficiency of the brush cutting work. .

またさらに、チップ６の厚さ方向の両側にそれぞれ鍔６ｇが形成されているため、両側の鍔６ｇによりチップ固着部９に対するチップ６のロー付け面積を大きくすることができ、チップ６の固着強度を大幅に高めて台金２からの脱落を抑制することができて、回転刃１の安全性をより一層高めることができると共に、例えばチップ６自体に十分な大きさの掬い面６ａ等を確保できて、チップ６の再研磨が可能になる等、回転刃１の切れ味の低下を抑えてその寿命を延ばすことが可能になる。 Furthermore, since the flanges 6g are formed on both sides of the chip 6 in the thickness direction, the brazing area of the chip 6 with respect to the chip fixing portion 9 can be increased by the flanges 6g on both sides, and the bonding strength of the chip 6 can be increased. Can be prevented from falling off the base metal 2 and the safety of the rotary blade 1 can be further enhanced, and for example, a sufficiently large scooping surface 6a is secured on the chip 6 itself. Thus, it is possible to extend the life of the rotary blade 1 by suppressing the sharpness of the rotary blade 1 such that the chip 6 can be repolished.

また、チップ６の鍔６ｇが側面視略Ｌ字形状に形成されているため、チップ６のチップ固着部９への嵌め込みを容易に行うことができると共に、一対の鍔６ｇ間の間隔寸法を台金２と略同一に設定することで、チップ６と台金２の位置関係が一義的に決定され、あさり寸法を簡単かつ確実に設定することができる等、ロー付け作業や研磨作業等の能率を向上させることができて、回転刃１のコストダウンを図ることが可能になる。 In addition, since the flange 6g of the chip 6 is formed in a substantially L shape when viewed from the side, the chip 6 can be easily fitted into the chip fixing portion 9, and the distance between the pair of flanges 6g can be reduced. By setting it approximately the same as the gold 2, the positional relationship between the chip 6 and the base metal 2 is uniquely determined, and the set-up dimensions can be set easily and reliably. Thus, the cost of the rotary blade 1 can be reduced.

また、回転刃１が、台金素材をプレス加工して、取付平坦部２ａと膨出部２ｂ及び刃先平坦部２ｃを成形する工程と、該工程で得られた台金２を熱処理する工程と、該熱処理後にチップ７をロー付けする工程等により製造されるため、取付ボルト１０を保護して頭部の摩耗等を抑制し、刈払い機５に対する交換作業等をスムーズに行うことができたり、刃先平坦部２ｃの反りを防止して良好な切れ味が得られる回転刃１を容易かつ安価に製造することができる。 In addition, the rotary blade 1 presses the base metal material to form the mounting flat portion 2a, the bulging portion 2b, and the blade edge flat portion 2c, and the step of heat-treating the base metal 2 obtained in the step. Since the chip 7 is manufactured by the process of brazing the chip 7 after the heat treatment, the mounting bolt 10 is protected to prevent head wear and the like, and the replacement work for the brush cutter 5 can be performed smoothly. Further, it is possible to easily and inexpensively manufacture the rotary blade 1 which can prevent warping of the flat edge portion 2c and obtain a good sharpness.

特に、台金素材の絞り加工時に、膨出部２ｂのアール寸法等を前述した寸法に設定することにより、台金素材として炭素鋼板を使用しても、膨出部２ｂの加工時の割れ等を防止して歩留まりを高めることができ、台金２のコストアップを極力抑えることができると共に、熱処理する工程を加熱加圧状態で行うことにより、取付平坦部２ａと刃先平坦部２ｃとが同一面状に設定されるため、一層良好な切れ味の回転刃１を安価に製造することができる。 In particular, when the base metal material is drawn, by setting the rounded dimension or the like of the bulging portion 2b to the above-described dimensions, even when a carbon steel plate is used as the base metal material, cracks during the processing of the bulging portion 2b, etc. And the yield can be increased, and the cost increase of the base metal 2 can be suppressed as much as possible, and the mounting flat portion 2a and the blade edge flat portion 2c are the same by performing the heat treatment process in a heated and pressurized state. Since it is set to be planar, the rotary blade 1 having a better sharpness can be manufactured at low cost.

なお、前記実施形態における、台金２の形態、連結維持部７の個数や形状、膨出部２ｂの幅等の形状、チップ６や台金２のチップ固着部９の形状等は一例であって、例えば連結維持部７を平面視で方形状、三角形状、多角形状等に形成したり、台金２の所定箇所に軽量孔を設ける等、本発明の各発明に係わる要旨を逸脱しない範囲において適宜の構成を採用することができる。 In the embodiment, the shape of the base metal 2, the number and shape of the connection maintaining portions 7, the shape such as the width of the bulging portion 2b, the shape of the chip 6 and the chip fixing portion 9 of the base metal 2 are examples. For example, the connection maintaining portion 7 is formed in a square shape, a triangular shape, a polygonal shape or the like in a plan view, or a lightweight hole is provided in a predetermined portion of the base metal 2. An appropriate configuration can be employed.

本発明は、円板状の台金の外周縁にチップが固着されたチップソーに限らず、台金の外周縁に刃先が一体形成された回転刃等、雑木等の刈払いに使用される全ての刈払い用回転刃に利用できる。 The present invention is not limited to the tip saw in which the tip is fixed to the outer peripheral edge of the disk-shaped base metal, but is used for cutting off miscellaneous trees and the like such as a rotary blade in which the cutting edge is integrally formed on the outer peripheral edge of the base metal. It can be used as a rotary blade for brush cutting.

１・・・刈払い用回転刃、２・・・台金、２ａ・・・取付平坦部、２ｂ・・・膨出部、２ｂ１、２ｂ２・・・側壁、２ｂ３・・・底部、２ｃ・・・刃先平坦部、３・・・取付孔、４・・・窪み部、５・・・刈払い機、６・・・チップ、７・・・連結維持部、７ａ・・・底部、８・・・刃室、９・・・チップ固着部、１０・・・取付ボルト、１１・・・巻付き防止カップ、１２・・・リベット。 DESCRIPTION OF SYMBOLS 1 ... Rotary blade for brush cutting, 2 ... Base metal, 2a ... Mounting flat part, 2b ... Expansion part, 2b1, 2b2 ... Side wall, 2b3 ... Bottom part, 2c ...・ Blade edge flat part, 3 ... Mounting hole, 4 ... Dimple part, 5 ... Crusher, 6 ... Chip, 7 ... Connection maintaining part, 7a ... Bottom part, ... -Blade chamber, 9 ... chip fixing part, 10 ... mounting bolt, 11 ... winding prevention cup, 12 ... rivet.

Claims

In the rotary blade for brush cutting having a cutting edge on the outer peripheral edge of a disk-shaped base metal, the base metal has a mounting flat portion in which a mounting hole for a brush cutter is formed in the central portion, and the mounting flat portion. An annular bulging portion formed in a state of projecting to the back side of the base metal which is the anti-brusher side on the outside, and the mounting flat portion on the outer side of the bulging portion toward the outer peripheral edge of the base metal And a cutting edge flat part extending substantially in the same plane,
The height of the bulging portion is set to be larger than the protruding dimension of the mounting bolt when the mounting flat portion is attached to the brush cutter with a mounting bolt, and the bulging portion has a predetermined position in the circumferential direction. the coupling holding section capable of maintaining a connection of the cutting edge flat portion and a mounting flat portion even if the bulging portion is worn is provided with a plurality, the connecting maintaining unit is mounted flat of the base metal of the bottom of the bulging portion The concave portion is provided by being dented to the portion side, and the bottom portion of the concave portion is inclined by setting the dimension with respect to the blade edge flat portion large on the mounting flat portion side and small on the blade edge flat portion side. Rotary blade for mowing.

2. The rotary blade for brush cutting according to claim 1, wherein the bulging portion is set to have an inclination angle of 20 to 45 degrees on a side wall on the flat portion of the blade tip that contacts the ground .