JP2010011844A - Composite blade for weed cutter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite blade for a weed cutter improving cutting power further by the synergy effect of a metal blade and a nylon code cutter. <P>SOLUTION: This composite blade for a weed cutter, bored with a mounting hole to the weed cutter at its center, and consisting of a controlling plate having a nylon code cutter-mounting part at its upper surface and a rotary blade made of a metal, capable of being freely mounted by overlapping to the lower surface of the controlling plate is characterized in that the outer edge of the controlling plate is formed so as to coincide with the outer edge of the rotary blade or set back from the outer edge of the rotary blade by a prescribed interval on mounting it to the weed cutter, and also on connecting a contacting point which is a contacting part of the controlling plate with the nylon code cutter at the upper surface of the controlling plate, has a highest position on the controlling plate and also is the nearest to the outer edge of the controlling plate, with the upper end of the outer edge of the rotary blade for weed-cutting by a straight line, the blade is formed so that the straight line has a prescribed horizontal angle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotary blade for a brush cutter, and more particularly to a configuration of a composite blade composed of a combination of a metal blade and a nylon cord cutter.

  Conventionally, rotary blades for brush cutters are generally four-blade or eight-blade, made of metal with a chip with dozens of blades, and a method using a nylon cord attached to a metal board as a blade. Is.

  Most of the mowing work is cutting near the root of the grass, so the cutting edge of the metal rotating blade that rotates at high speed, whether it is a 4-blade or 8-blade, violently rubs against the sand or soil adhering to the root. If the work is carried out for more than ten minutes, it is worn out and the cutting ability is significantly reduced. Therefore, in order to continue the work, it is necessary to interrupt the work and polish the blade using an electric grinder, but if there is no power supply nearby, even if you have an electric grinder, you can not polish and the replacement blade If it can be replaced, the work can be continued, but there is a problem that a number of replacement blades must be prepared in order to work for a long time.

  Furthermore, in the case of metal blades, grasses with long heights and ivy family plants tend to have a low cutting force because their stems are soft and easily entangled. On the other hand, the method using a nylon cord as a blade is effective for cutting away the relatively soft weeds that grow on the turf surface. However, when weeds with hard stems such as gramineous plants are mixed, the cutting power is extremely high. Decreases.

  Therefore, in order to compensate for the drawbacks of the metal blade and the nylon cord cutter, Patent Document 1 and Patent Document 2 disclose a rotary blade for a combined type mower that combines the two. However, in the invention described in Patent Document 1, a hole through which a nylon cord is passed is formed near the tip of a general metal 8-blade cutting edge. In this method, the nylon cord that rotates while being vibrated in a complicated and intense manner due to collision or entanglement with the object may touch the metal blade and be cut.

  Further, the invention described in Patent Document 2 is a structure in which a ring having a hole for attaching a string is attached under a metal blade, but there is no possibility that the nylon cord is cut like the rotating blade of Patent Document 1. Since the nylon cord is located under the metal blade when in use, the synergistic effect of the cord pulling force and the metal blade push-back pressure, which will be described later, cannot be obtained, and it is more effective than simply combining the metal blade and the nylon cord cutter. It was not something that could be obtained.

5-20530 JP 2000-308407 A

  Therefore, the present invention aims to provide a compound blade for a brush cutter that overcomes the disadvantages of the conventional rotary blade for a brush cutter and further improves the cutting force due to the synergistic effect of the metal blade and the nylon cord cutter. is there.

  The present invention solves the above-described problem, and includes a control plate having a brush cutter mounting hole in the center and a nylon cord cutter mounting portion on the upper surface, and a metal that can be mounted on the lower surface of the control plate. A compound blade for a brush cutter composed of a rotary blade made of the control blade, wherein the outer edge of the control plate is set to be set back from the outer edge of the rotary blade at a predetermined interval when the outer edge of the control plate is attached to the brush cutter. In addition, when the point that is the highest in the control plate and closest to the outer edge of the control plate and the upper edge of the outer edge of the rotary blade for cutting are connected by a straight line, the straight line has a predetermined horizontal angle. It is the compound blade for brush cutters characterized by being formed.

  Further, another aspect of the present invention is for a brush cutter, wherein the metal rotary blade and the control plate are formed with two or four blades having a specific shape so as to have the most synergistic effect when used. It is a composite blade.

  Furthermore, another aspect of the present invention is a compound blade for a brush cutter, wherein a protective plate is further overlapped on a lower surface of a metal rotary blade so as to be freely attached.

  That is, the compound blade for a brush cutter according to the present invention has a long length that has been difficult to cut due to a synergistic effect that is more than a simple combination of a conventional metal blade and a cord because the nylon cord is positioned above the metal blade. Grass and weeds such as grasses, ivy plants, or grasses with hard stems can be cut off without difficulty, enabling extremely efficient work. In addition, when the upper edge of the outer edge of the control plate and the upper edge of the outer edge of the metal blade are connected with a straight line, the horizontal angle is greater than the predetermined angle. Therefore, it is possible to maintain an appropriate interval, and to prevent the nylon cutter from being cut by the metal blade.

  Nylon cords wear out due to friction with the grass and soil of the object to be trimmed, but they are shortened, but because of the synergistic action with the metal blade, no excessive force is applied and the movement is ordered by the cord control plate. Therefore, durability is improved as compared with the nylon cord alone. In addition, since the metal blade can avoid collision with soil and rubble, the cutting force can be maintained for a long time.

  Further, in the present invention, when the metal blade is formed as a plurality of blades having a specific shape, the cutting edge of the metal blade is further increased because the blade edge strikes the object at a steep angle. Moreover, what attached the protective plate on the lower surface of a metal rotary blade further can protect a metal blade more effectively from the collision with soil or rubble.

The top view of the compound blade for brush cutters concerning this invention. The front view of the compound blade for brush cutters concerning this invention. Sectional drawing of the compound blade for brush cutters concerning this invention. The partial expanded sectional view of the compound blade for brush cutters concerning this invention. The partial expanded sectional view of the compound blade for brush cutters concerning this invention. The top view of the compound blade for brush cutters of the 2nd embodiment which concerns on this invention. The front view of the compound blade for brush cutters of the 2nd embodiment which concerns on this invention. Sectional drawing of the compound blade for brush cutters of the 2nd embodiment which concerns on this invention. The top view of the compound blade for brush cutters of the 3rd embodiment concerning the present invention. The front view of the compound blade for brush cutters of the 3rd embodiment concerning the present invention. The partial expanded sectional view of the compound blade for brush cutters of the 3rd embodiment concerning the present invention. The top view of the compound blade for brush cutters of the 4th embodiment which concerns on this invention. The front view of the compound blade for brush cutters of the 4th embodiment concerning the present invention. The figure which showed continuously the cutting principle by the synergistic action of a metal blade and a cord. The top view of the compound blade for brush cutters of the 5th embodiment which concerns on this invention. The front view of the compound blade for brush cutters of the 5th embodiment which concerns on this invention. Sectional drawing of the compound blade for brush cutters of the 5th embodiment which concerns on this invention. The top view of the lower protection board which concerns on this invention.

  Hereinafter, embodiments of the compound blade for a brush cutter according to the present invention will be specifically described with reference to the drawings. Note that the present invention is not limited to these embodiments.

  FIG. 1a is a plan view of a compound blade for a brush cutter according to the present invention, FIG. 1b is a front view thereof, and FIG. 1c is a sectional view thereof. In the figure, 1 is a control plate, 2 is a metal blade, 11 is a collar part, 12 is a nylon cord cutter mounting part, 13 is a brush cutter mounting hole, 21 is a blade part, 23 is a brush cutter mounting hole, and 121 is a hole part. Each is shown. As shown in the figure, the control plate 1 is formed in a perfect circular disk shape with a brush cutter mounting hole 13 formed in the center, and the flange portion 11 is formed so as to rise above the other portion at the peripheral edge. Has been. A cylindrical nylon cord cutter mounting portion 12 is provided on the upper surface of the control plate 1, and holes 121 for inserting the nylon cord cutter are drilled at eight locations on the wall portion at the same interval. Has been. Moreover, the upper surface of the collar part 11 and the lower end of the hole part 121 are formed so that it may become substantially the same height, Thereby, the motion of the nylon cutter extended to the outer side of the control board 1 from the hole part 121 to a horizontal direction Arranged.

  On the lower surface of the control plate 1, a brush cutter mounting hole 23 is drilled, and a perfect circular metal blade 2 in which a saw blade 21 is continuously formed on the peripheral edge is overlapped and attached to the brush cutter. The metal blade of this embodiment may be a ready-made product of the type normally used for a brush cutter, but what is important here is the relative relationship between the control plate 1 and the metal blade 2. That is, when attached to the brush cutter, the outer edge of the control plate 1 is formed to be set back (retracted) slightly from the outer edge of the metal blade 2, and therefore the blade portion 21 of the metal blade 2 is controlled at the time of attachment. It will protrude outside the outer edge of the plate 1.

  Further, the relationship between the control plate 1 and the metal blade 2 will be described with reference to the enlarged sectional view of FIG. As shown in the figure, when the upper end 1a of the outer edge of the control plate 1 and the upper end 2a of the outer edge of the metal blade are connected by a straight line, the angle θ formed between the straight line and the control plate 1 and the metal blade 2 is The height X of the flange portion 11 that is the outer edge of the control plate 1 and the distance Y from the distal end of the flange portion 11 to the distal end of the blade portion 21 are formed so as to be 15 degrees or more. Thereby, an appropriate space | interval can be maintained between a nylon cutter and a metal blade at the time of use, and it becomes possible to prevent the nylon cutter cutting | disconnection by a metal blade. Here, the height X and the distance Y can be arbitrarily set so that the angle θ is 15 degrees or more.

  In this embodiment, the point specified as “the upper end 1a of the outer edge of the control plate 1” means, in other words, the highest point of the control plate 1 and the closest point to the outer edge. Therefore, depending on the shape of the control plate 1, this point is not limited to the upper end of the outer edge of the control plate 1.

  As described above, the collar portion 11 is formed so as to be higher than the other portions of the control plate 1 in order to arrange the nylon cutter in the horizontal direction and maintain an appropriate distance between the nylon cutter and the metal blade. However, as long as the condition that the angle θ is equal to or greater than 15 degrees in the horizontal direction is satisfied, the flange portion 11 may be formed to have a certain thickness as shown in FIG.

  With this configuration, the compound blade for a brush cutter of the present invention first cuts most of the weeds with its nylon cutter, and the weeds that could not be cut with the nylon cutter with a metal blade. For example, the object can be drawn to a metal blade while being gripped by a nylon cutter, and can be cut with the pushing back pressure of the metal blade.

  Here, the cutting ability can be effectively exhibited when the hitting angle with respect to the metal blade of the object attracted by the nylon cutter is larger. The striking angle is related to the shape of the metal blade and the attachment position of the nylon cutter. In the case of a true circular metal blade as in this embodiment, the nylon cord cutter attachment portion 12 has an outer diameter of the metal blade 1. The outer diameter ratio is desirably 2: 1 or more.

  The control plate 1 and the rotary blade 2 are attached to the brush cutter by first superimposing the control plate 1 and the rotary blade 2 so that the brush cutter mounting holes are aligned, and then inserting the tip of the shaft through the brush cutter mounting hole 13. Then, it may be fixed with a fixing disk or the like from the brush cutter mounting hole 23 side.

  FIG. 4 shows a second embodiment of the compound blade for a brush cutter according to the present invention, wherein FIG. 4a is a plan view thereof, FIG. 4b is a side view thereof, and FIG. 4c is a sectional view thereof. As shown in the figure, in the compound blade for a brush cutter according to the second embodiment, both the control plate 1 and the metal blade 2 protrude in a symmetric direction around the brush cutter mounting hole, and proceed when the protruding portion rotates. The side portion that is the direction side is formed in an arc shape that gently curves in the rearward direction, and the side portion that is the rear side during rotation is formed in a straight line shape.

  The control plate 1 of the second embodiment has a plate shape with a uniform thickness on the entire surface, and a blade portion 21 in which a semicircular cutout is continuously formed on a side portion formed in an arc shape of the metal blade 2. Is provided. Further, the control plate 1 and the metal blade 2 are integrally fixed to each other by a rivet 14 so that the positional relationship between the control plate 1 and the metal blade 2 does not shift during use. When the control plate 1 has a uniform thickness as described above, the highest point of the control plate 1 and the closest point to the outer edge is the upper end 1a of the outer edge of the control plate 1, as shown in FIG. When connecting the upper edge 2a of the blade outer edge with a straight line, the height (thickness) of the control plate 1 and the distance from the outer edge of the control plate 1 to the outer edge of the blade portion 21 are such that the angle θ is 15 degrees or more horizontally. Is formed.

  A nylon cord cutter attachment portion 12 is provided on the upper surface of the control plate 1, but the second embodiment has a length adjusting notch 122 formed in an L shape from the upper end of the wall portion. First, the base end portion of the nylon cord cutter is locked to the length adjustment notch 122, and then the tip end side is passed through the hole portion 121 and extended to the outside, and the nylon cord cutter is worn and shortened. In this case, the length of the nylon cord cutter is adjusted by appropriately changing the position of the adjustment notch 122 to be locked. Moreover, the thing of this embodiment is provided with the lower end of the hole part 121 at the substantially same height as the upper surface of the control board 1, and can arrange | position a nylon cutter in a horizontal direction by this, at the time of use.

  Thus, by making the rotary blade into a specific shape as described above instead of a perfect circle, the blade portion strikes the object at a larger angle when the metal blade rotates, so that the cutting force of the metal blade is further increased. .

  FIG. 5 shows a third embodiment of a compound blade for a brush cutter according to the present invention, in which FIG. 5a is a plan view and FIG. 5b is a front view thereof. As shown in the figure, in the compound blade for a brush cutter of this embodiment, both the control plate 1 and the metal blade 2 protrude in three directions around the brush cutter mounting hole, and the side portion that becomes the traveling direction side at the time of rotation is shown. It is formed in an arc shape that gently draws an arc toward the rear, and a side portion that is the rear side during rotation is formed in a straight line shape.

  The control plate 1 of the third embodiment is provided with a taper 15 that is inclined toward the metal blade 2 at the outer edge of the arc-shaped side. And the edge part formed in the circular arc shape of the metal blade 2 is provided with the blade part 21 which formed the semicircle-shaped notch continuously. Further, the control plate 1 and the metal blade 2 are integrally fixed to each other by a rivet 14 so that the positional relationship between the control plate 1 and the metal blade 2 does not shift during use. Further, as shown in the enlarged sectional view of FIG. 5c, when the outer edge upper end 1a of the control plate 1 and the outer edge upper end 2a of the metal blade are connected by a straight line, the control plate is set so that the angle θ is 15 degrees or more horizontally. 1 and a distance from the outer edge of the control plate 1 to the outer edge of the blade portion 21 are formed.

  FIG. 6 shows a fourth embodiment of the four blades of the brush cutter composite blade according to the present invention, FIG. 6a is a plan view thereof, and FIG. 6b is a front view thereof. As shown in the figure, in the compound blade for a brush cutter of this embodiment, both the control plate 1 and the metal blade 2 project in four directions around the brush cutter mounting hole, and the projecting portion on the traveling direction side when rotating. Are formed in an arc shape that gently draws an arc, and the side portion of the protruding portion that is the rear side during rotation is formed in a straight line shape.

  The control plate 1 and the metal blade 2 of the fourth embodiment are formed so that their outer edges completely coincide with each other when they are attached to the reaper, and the control plate 1 has a side portion that is the rear side when rotating. A taper 15 is provided on the outer edge other than. Further, a blade portion 151 and a blade portion 21 in which semicircular cutouts are continuously formed are provided at the same position on the arc-shaped protruding portions of the control plate 1 and the metal blade 2.

  As described above, since the outer edge of the control plate 1 and the metal blade 2 of the fourth embodiment are coincident, the angle of the taper 15 corresponds to the straight line connecting the upper edge of the outer edge of the control plate 1 and the upper edge of the metal blade outer edge as it is. To do. Accordingly, the inclination of the taper 15 is formed so that the angle is 15 degrees or more in the horizontal direction.

  Below, the cutting principle by the synergistic action of a metal blade and a cord will be described based on FIGS. 7a to 7d. The cutting object is assumed to be a grass stalk standing vertically. FIG. 7a shows the situation where the cord has contacted the object. FIG. 7b shows a situation where the cord is tangled with the object, the tip of the object is bent in the direction of rotation, the part where the object is whipped is bent in the direction of rotation, and the upper part is bent to the opposite side of the code due to inertia to stop. The cord is pulled toward the metal blade while holding the object with a strong frictional force due to winding. Most of the grass is cut at this stage because the object is squeezed while being pulled strongly. FIG. 7 c shows a situation in which the metal blade is bitten and cut by the synergistic action of the cord pulling force and the metal blade pushing back pressure on the object that was not cut only by the cord. FIG. 7d shows a situation where the cord is released from the object and stretched by centrifugal force.

  If this cutting principle is compared to an operation in which a person harvests rice with a sickle, the left hand cord grabs and pulls the rice strain, and the metal blade corresponding to the right hand sickle strikes and cuts the lower part of the rice strain that the cord grabbed and pulled. . You can't cut a rope just by applying a knife blade to a hanging rope, but you can easily cut it by applying a strong pulling blade. The same is true for rice stocks, and the metal blades can easily cut the rice stock because the cord is pulled strongly. That is, this is the synergistic action of the cord and the metal blade described above. However, the cord that grabbed and pulled the rice strain tilted down and straddled the metal blade. If this is the case, it will be cut into a metal blade, so a cord control panel with a certain thickness will be attached to guide the movement of the cord to be parallel to the metal blade surface, and a gap will be created between the metal blade and cutting with the metal blade. It is preventing.

  FIG. 8 shows a fifth embodiment in which a protective plate is further attached to the compound blade for a brush cutter according to the present invention. FIG. 8a is a plan view thereof, FIG. 8b is a front view thereof, and FIG. As shown in the figure, the compound blade for a brush cutter according to the present embodiment is provided with an annular convex portion 16 in the vicinity of the outer peripheral edge of the control plate 1, and the convex portion 16 and the nylon cord cutter mounting portion 12 are provided on the control plate 1. It is formed by drawing a part of. A protective plate 3 is further attached to the lower part of the metal blade 2. As shown in the figure, an annular convex portion 34 projecting downward is provided in the vicinity of the outer peripheral edge of the protective plate 3.

  In the brush cutter composite blade of this embodiment, the highest point on the control plate 1 and the closest point to the outer edge is the upper end 16a of the outer edge of the convex portion, and this point is connected to the upper end 2a of the outer edge of the metal blade with a straight line. In this case, the horizontal angle is 15 degrees or more.

  The ratio of the radius A of the nylon cord cutter attachment portion 12 and the radius B of the metal blade 2 in the compound blade for a brush cutter of this embodiment is formed to be about 1: 2, and the outer circumference of the nylon cord cutter attachment portion 12 is The ratio of the distance C from the surface to the upper end of the outer edge of the convex portion 34 and the distance D from the outer peripheral surface of the nylon cord cutter mounting portion 12 to the outer edge of the metal blade 2 is approximately 1: 2.

  The effects produced by attaching the protective plate 3 are as follows. That is, in the mowing work in grasslands with a lot of pebbles and rubble, in the case of the compound blade for a brush cutter according to the first to fourth embodiments of the present invention, the weeds are first removed by the nylon cord, so that the ground can be visually recognized. The metal blade can be avoided from colliding with pebbles. However, it is difficult to avoid cutting after seeing obstacles when chopping the bushes of the brush cutter rhythmically from side to side, and the lower part of the metal blade must be rubbed against pebbles and rubble. For this reason, it is difficult to prevent the metal blade from being damaged even if it is carefully operated. In that respect, in the compound blade for a brush cutter of the present embodiment in which the protective plate 3 is attached to the lower part of the metal blade 2, the distance between the obstacle such as pebbles and rubble and the metal blade can always be kept constant. Can effectively prevent damage. Furthermore, in the weed cutting operation on the turf surface without any obstacles, the height of the metal blade is kept constant, so that the turf surface having the same height can be made efficiently.

DESCRIPTION OF SYMBOLS 1 ...... Control board 2 ...... Metal blade 3 ...... Protection plate 11 ...... Gutter part 12 ...... Nylon cord cutter attachment part 13 ...... Brush cutter attachment hole 14 ...... Rivet 15 ...... Taper 16 ...... Convex part 21 ... ... Blade 22 ... ... Length adjustment notch 23 ... ... Brusher mounting hole 31 ... ... Blade retainer 32 ... ... Joint bolt 33 ... ... Brusher mounting hole 34 ... ... Protrusion 121 ... ... Hole 151 ... ... Blade part 1a ... ... Upper edge 2a of control plate 1 ... Upper edge of metal blade outer edge 16a ... ... Upper edge of outer edge of convex part X ... ... Height of outer edge of control plate Y ... ... Metal blade outer edge from control plate outer edge Distance θ ... ... Angle formed when the outer edge upper end of the control plate and the metal blade outer edge upper end are connected by a straight line A ... ... Radius B of the nylon cord cutter mounting portion 12 ... ... Radius C of the metal blade 2 ... Na The distance from the outer peripheral surface of the iron cord cutter mounting portion 12 to the upper end of the outer edge of the convex portion D ... The distance from the outer peripheral surface of the nylon cord cutter mounting portion 12 to the outer edge of the metal blade 2
more than

Claims (9)

  This is a compound blade for a brush cutter consisting of a control plate having a nylon cord cutter mounting portion on the upper surface and a metal rotary blade that can be mounted on the lower surface of the control plate. The outer edge of the control plate is set to be set back from the outer edge of the rotary blade at a predetermined interval when the outer edge of the control plate is attached to the brush cutter. A compound for a brush cutter, characterized in that when a point close to the outer edge of the control plate and the upper edge of the outer edge of the rotary blade for cutting are connected by a straight line, the straight line has a predetermined horizontal angle. blade.   2. The compound blade for a brush cutter according to claim 1, wherein the predetermined horizontal angle is 15 degrees or more.   The nylon cord mounting portion for brush cutting protrudes in an annular shape on the upper surface of the control plate, and a hole for inserting the nylon cord is provided in the peripheral wall portion. The compound blade for brush cutters in any one.   The metal blade has a shape that protrudes in a symmetric direction around the brush cutter mounting hole, and two blades or four blades provided with a blade portion on the side that is the rotation direction side of the metal blade in the protruding portion The compound blade for a brush cutter according to any one of claims 1 to 3, wherein the blade is a blade.   5. The compound blade for a brush cutter according to claim 4, wherein the blade portion is formed by continuously forming a semicircular cutout.   The position of the hole is provided so that the lower end of the hole and the upper surface of at least the outer peripheral edge of the control plate have substantially the same height. Combined blade for brush cutter as described.   The compound blade for a brush cutter according to any one of claims 1 to 6, wherein the highest point in the control plate and the closest point to the outer edge of the control plate is an upper end of the outer edge of the control plate.   2. A convex portion projecting annularly on the upper surface of the control plate, wherein the highest point in the control plate and closest to the outer edge of the control plate is the upper end of the outer edge of the convex portion. The compound blade for brush cutters of any one of thru | or 6. The compound blade for a brush cutter according to any one of claims 1 to 8, wherein a lower protection plate can be further overlapped and attached to the lower surface of the rotary blade for brush cutting.

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