JP2008062635A - Rotary blade and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary blade inexpensively made by solving problems on manufacturing, and efficiently cutting miscellaneous small trees, etc., so as to prolong service life of the rotary blade and the like, and its manufacturing method. <P>SOLUTION: This rotary blade comprises a disk-like metal base in which a lug hole for a bush cutter or the like is bored to the center position and teeth 5 are formed at prescribed intervals on the outer peripheral part of the metal base. The teeth includes folded parts formed by folding the metal base itself in the plate thickness direction and in which the folded tip is protruded by prescribed dimensions from the front and rear surfaces of the metal base, and blade edge 5b formed at the end of the folded parts in the rotating direction. In the teeth, an angle α1 at the blade edge of the folded parts and an angle α2 at the anti-blade edge side are set to be α1>α2, and the width w1 of the blade edge and the width w2 of the anti-blade edge side each in the plate thickness direction of the blade edge of the folded parts are set to be w1>w2. Also the teeth have limiting blades 6 provided via gullets 7b ahead in the rotating direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotary blade suitable for use in cutting, for example, miscellaneous trees and a method for manufacturing the rotary blade.

Conventionally, as rotary blades used for cutting miscellaneous trees, for example, those disclosed in Patent Document 1 and Patent Document 2 are known. Among these, the rotary blade disclosed in Patent Document 1 is formed by forming a large number of chip mounting portions on the outer peripheral edge of a disk-shaped base metal, and brazing and fixing a cemented carbide chip to each of these chip mounting portions with silver solder. is there. Moreover, the rotary blade disclosed in Patent Document 2 is formed by directly forming a blade portion having a sharp blade on the front end side in the rotation direction on the outer peripheral edge of a base metal plate, and forming the entire shape into a circular saw shape. It is.
JP-A-11-332348 JP 2005-176746 A

  However, in the rotary blade disclosed in Patent Document 1, although a desired cutting performance can be obtained with respect to weeds and extremely thin weeds by the cemented carbide tip as the blade portion, the base metal is attached to the tip mounting portion formed on the base metal. For example, a silver solder containing about 46% silver is necessary for fixing the carbide chip, which is not preferable in terms of saving of limited silver resources. In addition, a flux is also required to fix the chip, and this flux is easily evaporated and heated to be scattered, thereby deteriorating the work environment and the human body respiratory system. , Have various problems in the manufacture of rotary blades. Furthermore, since the vegetation is cut with the cemented carbide tip fixed to the base metal, for example, when trying to cut (prune away) miscellaneous trees with an outer diameter of 100 mm or more, the load applied to the cemented carbide tip increases. Depending on the fixed state of the hard tip, the tip may be chipped, which is not preferable in terms of the life of the rotary blade.

  On the other hand, in the rotary blade disclosed in Patent Document 2, since the blade portion is directly formed on the base metal, although the manufacturing problems of the rotary blade disclosed in Patent Document 1 can be solved to some extent, the blade portion is the base metal. By forming the outer peripheral edge of the blade in a thin state in the plate thickness direction, a sharp blade is formed on the tip side in the rotational direction, that is, the blade portion is formed so that the thickness of the blade portion is thinner than the plate thickness of the base metal. For example, when trying to cut a miscellaneous tree having an outer diameter of 100 mm or more, miscellaneous tree sap generated at the time of cutting is clogged in the cutting portion, and an excessive load is applied to the rotary blade, making it difficult to obtain a good rotation state. The burden on the engine of the brush cutter to which the rotary blade is attached also increases, and there is a concern that these lifetimes may be reduced.

  The present invention has been made in view of such circumstances, and its purpose is to solve various manufacturing problems and form a rotary blade at a low cost, and to efficiently cut miscellaneous trees etc. An object of the present invention is to provide a rotary blade capable of extending the service life and a manufacturing method thereof.

  In order to achieve such an object, the invention (rotating blade) according to claim 1 of the present invention includes a disk-shaped base metal having a mounting hole formed at a central position, and an outer peripheral edge portion of the base metal. A blade portion formed at a predetermined interval, and the blade portion bends the base metal in the plate thickness direction, and the bent tip protrudes from the front and back surfaces of the base metal by a predetermined dimension in the plate thickness direction. And a cutting edge formed at the rotational direction end of the bent portion.

  And as for the said blade part, the angle (alpha) 1 of the blade edge | tip of the said bending part and the angle (alpha) 2 of the non-blade edge side are set to (alpha) 1> (alpha) 2 like the invention of Claim 2, or Claim 3. As in the invention, the width w1 in the plate thickness direction of the cutting edge of the bent portion and the same width w2 on the side opposite to the cutting edge are preferably set to w1> w2. Further, as in the invention described in claim 4, it is preferable that the bent portion is formed so as to protrude alternately in the plate thickness direction with respect to the rotation direction of the base metal. As in the invention described in 5, it is preferable to have a limiting blade provided in front of the rotation direction via a tooth chamber.

  Further, the invention according to claim 6 (a method for manufacturing a rotary blade) is obtained by a substrate forming step of forming a disk-shaped base metal having a mounting hole formed at a central position, and the substrate forming step. The base metal itself is bent at the outer peripheral edge of the base metal at a predetermined interval in the plate thickness direction, and the bent tip protrudes from the front and back surfaces of the base metal by a predetermined dimension in the plate thickness direction, and the rotational end of the bent portion The blade part forming process which shape | molds the blade edge | tip formed in the part, and the process process which performs various processes to the blade part obtained by this blade part shaping | molding process are characterized by the above-mentioned. In this case, it is preferable that the bending portion and the cutting edge are simultaneously formed in the blade portion forming step as in the invention described in claim 7.

  According to the first aspect of the present invention, the blade portions formed at predetermined intervals on the outer peripheral edge portion of the base metal bend the base metal itself in the plate thickness direction, and the bent tip is the base metal front and back surfaces. Since it has a bent portion that protrudes by a predetermined dimension in the plate thickness direction and a cutting edge formed at the end of the bent portion in the rotational direction, there is no need to fix the carbide tip to the base metal, and resources such as silver Reduce costs by solving various problems related to the production of rotary blades, such as saving energy and preventing the adverse effects on the work environment and the human respiratory system by eliminating the need for flux. An inexpensive rotary blade can be obtained. In addition, clogging of sap etc. is suppressed by the bent part, and even a miscellaneous tree with a relatively large outer diameter can be cut well while reducing the burden on the rotary blade itself and the brush cutter, and the life of the rotary blade etc. Can be extended.

  Further, according to the invention described in claim 2, in addition to the effect of the invention described in claim 1, the angle of the cutting edge of the bent portion (crease angle) is set larger than the angle on the side opposite to the cutting edge. The cutting performance of the cutting edge can be improved to cut miscellaneous trees and the like better.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, the width in the plate thickness direction of the cutting edge of the bent portion is set to be larger than the width on the side opposite to the cutting edge. For this reason, the rigidity of the blade edge can be increased to cut miscellaneous trees and the like, and the life of the rotary blade can be further extended.

  According to the invention described in claim 4, in addition to the effects of the invention described in claims 1 to 3, the bent portions are alternately formed in the plate thickness direction with respect to the rotation direction of the base metal. The cutting width according to the protruding dimension of the bent portion in both directions of the base metal can efficiently cut miscellaneous trees and the like while further preventing clogging of the sap.

  Furthermore, according to the invention described in claim 5, in addition to the effects of the invention described in claims 1 to 4, the blade portion has the limiting blade provided in front of the rotation direction via the tooth chamber, so that the limitation The cutting of miscellaneous trees and the like can be guided by the blade, and the cutting can be performed better and more efficiently than miscellaneous trees and the like.

  Further, according to the invention described in claim 6, since the substrate forming step, the blade portion forming step and the processing step for forming the bent portion and the cutting edge are provided, the brazing step becomes unnecessary, and the resources such as silver can be saved. Solve various problems in the manufacture of rotating blades, such as reducing the working environment due to flux and preventing adverse effects on the human respiratory system, etc., reducing costs and obtaining an inexpensive rotating blade In addition to being able to cut clogging of sap, etc. by the bent part, it can cut well even if it is miscellaneous trees etc. with a relatively large outer diameter while reducing the burden on the rotary blade and brush cutter, etc. Can extend the lifespan.

  Further, according to the invention described in claim 7, in addition to the effect of the invention described in claim 6, since the bending portion and the cutting edge are simultaneously formed in the blade portion forming step, for example, each blade portion or all of the blade portions. The bent part and the cutting edge of the blade part can be simultaneously formed, and the manufacturing cost of the rotary blade can be further reduced.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
1 to 7 show an embodiment of a rotary blade according to the present invention, FIG. 1 is a plan view thereof, FIGS. 2 to 4 are side views and enlarged views of essential parts thereof, and line AA in FIG. FIG. 5 is a process diagram showing an example of the manufacturing method, and FIGS. 6 and 7 are explanatory diagrams thereof.

  In FIG. 1, the rotary blade 1 has a disk-shaped base metal 2 formed of a steel plate having a plate thickness t (see FIG. 2) of 1.3 to 1.4 mm and an outer diameter of 203 to 255 mm, for example. An attachment hole 3 having a predetermined inner diameter for attachment to a brush cutter (not shown) is formed at the center position of the base metal 2, and a large number of blade parts 4 are arranged on the outer peripheral edge 2 a of the base metal 2. For example, it is formed at regular intervals in the direction. The blade portion 4 has a bent portion 5 having a cutting edge, which will be described later, and a limiting blade 6 formed before and after the bent portion 5 via tooth chambers 7a and 7b.

  As shown in FIGS. 2 to 4, the bent portion 5 is formed to have a substantially flat outer edge portion 5 a by bending the outer peripheral edge portion 2 a of the base metal 2 in the plate thickness direction. Both ends in the width direction (bending tips) are projected from the front and back surfaces of the base metal 2 by predetermined dimensions t1 and t2. At this time, the bent portions 5 of the adjacent blade portions 4 are set so that the protruding directions thereof alternate with the front and back surfaces of the base metal 2 with respect to the rotational direction A. Further, the edge 5b of the bent portion 5 has an angle α1 (for example, 30 degrees), which is a rake angle with respect to the thickness direction of the base metal 2, at the end of the outer edge portion 5a in the rotational direction A, and has an inclined surface. And the end of the outer edge 5a, which is the end of the outer edge 5a in the counter-rotating direction (a), is set at a predetermined angle α2 (for example, 20 degrees) with respect to the thickness direction of the base metal 2. Has been.

  Further, the maximum widths w1 and w2 of the outer edge portion 5a of the bent portion 5 in the metal plate thickness direction are set such that the blade edge 5b side (w1) is large and the counter blade edge side 5c (w2) is small, so that the outer edge portion 5a. Are set such that both ends in the width direction of the blade edge 5b protrude from the front and back surfaces of the base metal 2 with respect to the front and rear surfaces of the base metal 2. Has been. Moreover, the front-rear width w3 (see FIG. 3) of the bent portion is set to be, for example, about 9.0 to 9.5 mm after polishing at 10 mm during molding described later. In addition, each dimension of the bending part 5 of this blade part 4 is an example, and it cannot be overemphasized that it can change suitably according to the number of the blade parts 4, the magnitude | size of the base metal 2 itself, etc. FIG. Moreover, the cross-sectional shape of the bent portion 5 is an appropriate shape shown in FIGS. The shape can be adopted.

  The limiting blades 6 are formed in front of the bent portions 5 so as to be continuous with the bent portions 5 via the tooth chambers 7a. At this time, the limiting blade 6 punches the base metal 2. By processing, it is formed with the same thickness as the thickness t of the base metal 2, and the front side in the rotational direction a is formed with a curved surface. In addition, as shown in FIG. 3, the height positional relationship between the limiting blade 6 and the bent portion 5 is such that the height of the limited blade 6 is h2 lower than the height h1 of the bent portion 5, that is, the bent portion. The outer peripheral edge of the fifth cutting edge 5 b is set so as to be located on the outermost side of the base metal 2. The shape of the limiting blade 6 is the same as the size of the bent portion 5 described above, for example, the thickness of the limiting blade 6 is changed to the thickness of the base metal 2 according to the number of the blade portions 4 and the size of the base metal 2. It can be changed as appropriate, for example, it is formed thicker than t.

  Next, an example of the manufacturing method of the rotary blade 1 having such a configuration will be described with reference to FIGS. As shown in FIG. 5, first, the mounting hole 3 is formed at the center position of the disk-shaped base metal 2 by stamping (cutting) processing of a steel plate press, and the outer peripheral edge portion 2 a of the base metal 2 is spaced at a constant interval. A blade portion forming portion (not shown) that can form the blade portion 4 and a limiting blade 6 are formed (K01). At this time, it is set so that the bent portion 5 and the blade edge 5b having the above-described shape can be obtained at the blade portion forming portion at the same time as pressing with a mold (not shown).

  When the processing of the base metal 2 is completed, the blade portion forming portion of the base metal 2 is bent by press processing to form the bent portion 5 (K02). This molding uses a plurality of molds 10a to 10c as shown in FIGS. 6 and 7, and is formed into a flat plate shape by convex portions 11 and concave portions 12 corresponding to the shapes of the bent portions 5 of the molds 10a and 10b. The blade forming portion is bent, and the bent portion 5 having the above-described shape is formed. The bent portion 5 can be formed for each blade portion 4 or all the blade portions 4 can be formed at the same time, and can be selected as appropriate depending on the equipment conditions to be used. Just do it.

  Part of this step K01 and step K02 are the blade forming step of the present invention, and after the step K02 is completed, the entire base metal 2 is quenched (K03) and tempered (K04) with an electric furnace. 2 is set to a predetermined hardness. Then, the base metal 2 is hammered (K05) to acclimate the limiting blade 6 portion of the blade part 4 and the base metal 2 itself flatly, and thereafter the blade part 4 is quenched (K06) by high frequency induction heating and the electric furnace. Temper (K07). As a result, the blade portion 4 has a predetermined hardness, and in this state, the blade portion 4 is polished (K08), and then the blade edge 5b indicated by hatching in FIG. 7 is polished (K09). By this polishing, the flat outer edge portion 5a of the bent portion 5 and both widthwise end portions thereof are polished, and the width w3 portion of the blade edge 5b is polished with the inclined surface of about 0.5 to 1 mm. As a result, the cutting edge 5b having excellent sharpness is obtained.

  When the blade part 4 is polished in steps K08 and K09, coating (K10) or marking (K11) is performed on a predetermined position of the base metal 2, and then packing (K12) is performed, and the manufacture of the rotary blade 1 is completed. An appropriate method may be employed for the coating process, the marking process, and the like as necessary. In addition, this manufacturing method is an example, For example, a suitable process can be employ | adopted according to an installation condition etc., for example, providing the grinding | polishing process of the blade part 4 in multiple steps in an appropriate position.

  As described above, according to the rotary blade 1 of the above embodiment, the blade portions 4 formed at predetermined intervals on the outer peripheral edge portion 2a of the base metal 2 bend the base metal 2 itself in the plate thickness direction and the bent tip thereof is In order to provide a bent portion 5 projecting from the front and rear surfaces of the base metal 2 in the plate thickness direction by predetermined dimensions t1 and t2 and a cutting edge 5b formed at an end portion in the rotational direction of the bent portion 5, Unlike the rotary blade shown, it is not necessary to fix the cemented carbide tip to the base metal, and a brazing material is not required, so that resources such as silver can be saved, and flux is not required. As a result, it is possible to solve various problems in the production of the rotary blade 1 such as the deterioration of the working environment and the adverse effects on the human respiratory system, and the cost can be reduced and the inexpensive rotary blade 1 can be obtained. .

  In addition, since the bent portions 5 projecting from the front and back surfaces of the base metal 2 of the blade portion 4 can suppress clogging of a cutting portion such as sap generated when cutting miscellaneous trees, a conventional rotary blade (Patent Document) 1 and the cutting blades disclosed in Patent Document 2), even if it is a miscellaneous tree having an outer diameter of about 100 mm, it can be cut satisfactorily while reducing the burden on the rotating blade 1 itself or the brush cutter. Thus, the service life of the rotary blade 1 and the brush cutter can be extended.

  In particular, the angle α1 of the cutting edge 5b of the bent portion 5 with respect to the plate thickness direction of the base metal 2 is set to be larger than the angle α2 of the counter cutting edge side 5c, or the width w1 of the cutting edge 5b of the bending portion 5 is the anti cutting edge side 5c. Is set to be larger than the width w2 of the blade, so that the rigidity and the like of the cutting edge 5b can be increased to cut off the miscellaneous tree and the like, and the life of the rotary blade 1 can be further extended. Since the protrusions are alternately formed in the plate thickness direction with respect to the rotation direction A of the gold 2, the clogging of the sap is further prevented by the cutting width according to the protrusion dimension of the bent portion 5 in both directions of the base metal. Can do. Further, since the blade portion 4 has the limiting blade 6 that does not protrude in the plate thickness direction of the base metal 2 through the tooth chambers 7a and 7b before and after the rotation direction A, cutting of miscellaneous trees and the like can be guided by the limiting blade 6. Thus, it becomes possible to cut miscellaneous trees and the like even better and efficiently.

  Regarding the cutting performance of this miscellaneous tree, when the rotary blade 1 having the above-described shape setting was manufactured and a moist miscellaneous tree cutting experiment having an outer diameter of about 100 mm was conducted, the effect was sufficiently confirmed. That is, in the case of the conventional (Patent Document 1) rotary blade, it is impossible to use the rotary blade by cutting about 300, whereas in the case of the rotary blade 1 of the present invention, even if 500 are cut, It has been confirmed that it can be used. At the same time, it has been confirmed that the burden on the worker during cutting work is greatly reduced by improving cutting performance.

  Note that the present invention can be used only for cutting an object having a relatively outer diameter such as a miscellaneous tree due to the structural features of the blade portion 4, but by attaching it to a brush cutter, It can be used in the same manner as a rotary blade such as a tip saw, and of course can also be used for mowing work such as undergrowth in mountains where thick trees grow. Moreover, in the said embodiment, although each bending part 5 was made to protrude alternately on the front and back of base metal 2, for example, as shown in FIG. It is also possible to project only on the front surface side or the back surface side, and so that the projecting directions of the bent portions 5 are alternate.

  Furthermore, in the said embodiment, although the limiting blade 6 was each provided between the adjacent bending parts 5, for example, the limiting blade 6 can also be provided every other (or every plurality) of the adjacent bending parts 5. In some cases, the limiting blade 6 can be omitted. Moreover, in the said embodiment, although the bending part 5 and the limiting blade 6 were integrally formed by the process of the base metal 2, this invention does not exclude combined use with the conventional carbide | carbonized_material chip | tip, and it is super It is also possible to adopt a structure in which a hard chip is fixed.

  The present invention is not limited to a rotary blade attached to a brush cutter, but can be applied to, for example, an electric motor that can be held by hand, a rotary blade that is directly attached to a rotary shaft of an engine, and the like.

  The top view which shows one Embodiment of the rotary blade concerning this invention   Side view of the main part   1 is an enlarged view of the main part of FIG.   AA arrow view of FIG.   Process drawing which shows an example of the manufacturing method of the rotary blade concerning this invention   Explanation of the same   Other explanatory diagrams

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Rotary blade, 2 ... Base metal, 2a ... Outer peripheral edge part, 3 ... Mounting hole, 4 ... Blade part, 5 ... Bending part, 5a ... Outer edge part 5b ... blade edge, 5c ... anti-blade edge side, 6 ... restriction blade, 7a, 7b ... tooth chamber, 10a, 10b, 10c ... mold, 11 ... convex part, 12 ... Recess.

Claims (7)

A disk-shaped base metal having a mounting hole drilled at a central position, and blade parts formed at predetermined intervals on the outer peripheral edge of the base metal,
The blade portion is formed at a bent portion in which the base metal itself is bent in the plate thickness direction and the bent tip protrudes from the front and rear surfaces of the base metal by a predetermined dimension in the plate thickness direction, and at the rotation direction end of the bent portion. A rotary blade comprising a cutting edge.   2. The rotary blade according to claim 1, wherein an angle α <b> 1 of the cutting edge of the bent portion and an angle α <b> 2 on the side opposite to the cutting edge are set to α <b> 1> α <b> 2.   The rotation according to claim 1 or 2, wherein the blade portion has a width w1 in the plate thickness direction of the blade edge of the bent portion and the same width w2 on the opposite blade edge side set to w1> w2. blade.   The rotary blade according to any one of claims 1 to 3, wherein the bent portions are formed to protrude alternately in the plate thickness direction with respect to the rotation direction of the base metal.   The rotary blade according to any one of claims 1 to 4, wherein the blade portion has a limiting blade provided in front of the rotation direction via a tooth chamber.   A base plate forming step for forming a disc-shaped base metal having a mounting hole in the center position, and the base metal itself in the plate thickness direction at predetermined intervals on the outer peripheral edge of the base metal obtained in the base plate forming step. A blade portion forming step for forming a bent portion whose bent tip protrudes from the front and back surfaces of the base metal by a predetermined dimension in the plate thickness direction and a blade edge formed at the rotation direction end portion of the bent portion; And a processing step of performing various types of processing on the blade portion obtained in the part forming step.   The method for manufacturing a rotary blade according to claim 6, wherein in the blade portion forming step, the bent portion and the cutting edge are formed simultaneously.

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