JPH07177812A - Rotation blade of power bush cutter - Google Patents

Abstract

PURPOSE:To provide a rotating reaping blade lowered in cost in production process while paying attention so as to enable ready handling in using. CONSTITUTION:In this rotating reaping blade, an attaching part 3 of an elastic cord 9 is constituted by using two or more winding blocks having folding edge parts 1 as a set and a set of the attaching parts 3 is arranged in the vicinity of the outer circumference of an attaching disc 4 symmetrically in points using a center shaft hole of the attaching disk 4 as a standard and one end of the elastic cord 9 is held to the attaching part 3. In the attaching disk 4, a rib 5 is provided on the outer edge and a protruded part 6 higher than the winding block 2 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary cutting blade of a power brush cutter for cutting grass and weeds with an elastic cord that rotates at high speed.

[0002]

2. Description of the Related Art A power brush cutter for mowing grass and weeds
Usually, for safety and easy handling, an elastic cord such as a hard synthetic resin cord or spring material cord is used as a cutting blade, and this elastic cord is attached to a rotating disc that rotates at high speed to configure a rotary cutting blade. There is. Conventional rotary cutting blade is actually fair 2-
As seen in No. 44023 and No. 2-9626, it is common for the mounting part that holds the elastic cord to be sandwiched between two discs. Normally, two or more members are processed, The method of assembling and manufacturing is adopted.

[0003]

As described above, in the conventional rotary cutting blade, for the purpose of holding the elastic cord attached to the attaching portion, the attaching portion is composed of two discs so that the elastic cord can be held. It has a sandwiched structure. This means that processing and manufacturing are required separately in the manufacturing process, and an assembling process is required. In addition, the elastic cord bites between the two discs, and grass invades during use, which makes maintenance difficult.

In any of the manufactured products, it is still possible to reduce the raw material cost, the manufacturing cost, and the personnel cost related to the cost in order to reduce the cost. Therefore, in order to reduce the cost in the manufacturing process of the above-described conventional rotary cutting blade, it was decided to study the structure of the rotary cutting blade of the power brush cutter in consideration of easy handling.

[0005]

As a result of the successful development, the elastic cord mounting portion 3 is formed by combining two or more winding blocks 2 each having a folded edge portion 1 and a mounting disk 4 is provided. Is a rotary cutting blade of a power brush cutter in which a pair of these mounting portions 3 are arranged in the vicinity of the outer circumference of the mounting disk 4 in a point symmetry with respect to the central axis hole of the above, and one end of an elastic cord is locked to the mounting portion 3. .

The outer shape of the winding block is most preferably a smooth one, especially a circular one, but any shape may be used as long as the side surface of the cross section perpendicular to the radial direction is smoothly curved. Further, two or more sets of the winding blocks, preferably three or more sets as one set, the folded edge portions are close to each other, and the distance between the holes is slightly larger than the diameter of the elastic cord to be attached. The mounting portion may be configured in this way. There may be one or more sets of such mounting portions on a diagonal line, and a plurality of sets may be arranged.

Further, a rib 5 is provided on the outer edge of the mounting disk 4 of the present invention.
Alternatively, the mounting disk 4 may be provided with a convex portion 6 higher than the winding block 2. It is preferable to provide the ribs all around the outer circumference of the mounting disk, and for the convex portion, the shape does not matter as long as it is on the upper surface of the mounting disk other than the winding block, and the horizontal section is circular, square, or other complicated shape. It may be one. The mounting disk, the winding block, the rib and the convex portion may be integrally formed by pressing or burring with a metal material.

[0008]

The rotary cutting blade of the power brush cutter according to the present invention comprises three or more winding blocks 2 each having an elastic cord having a locking end (for example, a bulge is formed by bending, a knot is provided at the cord end). In the case of the mounting portion 3 consisting of, the both ends of the cord are turned outward, and the cord is wound around the inner winding blocks not located at both ends and locked by the folded edge portions 1, 1 of the opposing winding blocks, or two In the case of the attachment part made up of the winding block 2, the elastic cord has its normal end (a normal cord end without a knot) opposite to the locking end directed outwards between the winding blocks, and is simply attached to the elastic cord. The locking end is held by being locked by the folded edge portions 1, 1 of the winding block facing each other.

Centrifugal force (outward force) due to rotation at the normal end
Is applied, in the case of the mounting portion 3 composed of three or more winding blocks 2, inward force is applied to the locking end of the cord,
In the case of a mounting part consisting of two winding blocks, to the locking end of the cord, the locking end of the elastic cord is pressed against the folded-back edges 1 and 1 of the winding blocks arranged in close proximity. An outward force is applied, and the locking ends of the elastic cords are pressed against the folded edges 1, 1 of the winding blocks arranged in close proximity to lock them. At this time, by smoothing the outer shape of the winding block, it is possible to prevent the elastic cord from being worn or damaged by centrifugal force,
The folded edge 1 prevents the elastic cord from deviating from the mounting portion 3 when the rotary cutting blade rotates at high speed.

As described above, the rotary cutting blade of the present invention has two means for attaching the elastic cord to the attachment portion thereof, and particularly, in the case of the attachment portion 3 composed of three or more winding blocks 2, The elastic cord can be cut off from a reel or the like and directly locked to the mounting portion 3. The method of
Although it can be applied to the mounting portion 3 including three or more winding blocks, the description has been given here only to the case of two winding blocks.

The rib 5 and the convex portion 6 are mounted on the mounting disk 4 respectively.
Alternatively, in order to prevent the take-up block 2 from rubbing against the ground and being worn away to form a sharp edged tool, the take-up block 2 is brought into contact with the ground or the like instead of the above-mentioned respective parts to prevent damage or wear. The ribs 5 prevent the mounting disk 4 from coming into contact with the ground or the like and being worn when the rotary cutting blade is normally used. The convex portion 6 mainly prevents the winding block 2 from being worn due to the same reason as described above when the rotary cutting blade is attached inside out on the power brush cutter.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the first embodiment, in which three winding blocks, which are through-holes, are set as a set and are arranged in a pair on a diagonal line on the upper surface of the mounting disc, and on the concentric arc of the mounting portion and between the mounting portions. An upward convex portion having a trapezoidal cross section and a downward rib on the outer periphery of the mounting disk are all integrally molded from a metal disk to the power brush cutter of the rotary cutting blade of the present invention. It is a perspective view showing the mounting relationship,
2 is a plan view of the embodiment, FIG. 3 is a sectional view taken along line AA in FIG. 2, and FIG. 4 is a sectional view taken along line BB in FIG. Incidentally, FIG. 5 shows a sectional view corresponding to FIG. 3 formed by plastic molding.

As shown in FIGS. 1 and 2, a power brush cutter 12
The mounting disk 4 having a central shaft hole 13 to be mounted on is a metal disk integrally formed with a downwardly directed rib 5 on the outer periphery, and constitutes a winding block 2 which is locked by winding one end of an elastic cord. The portion 3 and the convex portion 6 are arranged concentrically on the upper surface of the mounting disk 4. The winding block 2 has a concave surface with a smooth side surface 7 and has a shape of a through hole having a folded edge portion 1 at the outer periphery of the upper end, and the edge penetrating the mounting disk 4 is formed by burring. This is because the winding block is formed integrally with the mounting disk to simplify the manufacturing process, and the winding block does not need to be a through hole. The winding block 2 comprises a set of three winding blocks 2 arranged close to each other by the width of the elastic cord 9, and the mounting portions 3 are arranged diagonally on the upper surface of the mounting disk 4.

The convex portion 6 is on a circular arc concentric with the mounting portion 3,
In addition, it is arranged between the mounting portions 3 and has a trapezoidal cross section, the side surfaces are inclined upward, and the plane is fan-shaped. This convex portion 6
Can be formed by pressing the mounting disk 4. The height of the convex portion may be slightly higher than that of the winding block, and the convex portion may have a larger shape and a complicated shape.

The significance of the convex portion 6 is that when the rotary cutting blade is mounted inside out on the power brush cutter, the winding block 2 is attached to the ground.
The point is that the contact is made earlier than before and the abrasion of the winding block 2 is prevented. This is useful when the rotary cutting blade is installed upside down when the protective cover, which is installed so as to prevent cut grass from entering between the rotary cutting blade and the power brush cutter, buffers the winding block 2. The ribs 5 on the outer circumference of the mounting disk 4 function in the same manner as the convex portions 6 when the rotary cutting blade is normally mounted on the power brush cutter, and prevent the mounting disk 4 from being worn. This prevents the risk of the disc becoming worn and having a sharp edged edge.

As shown in FIGS. 1 and 2, the rotary cutting blade of the present invention is a set of three in which an elastic cord 9 having a locking end 10 is attached to the mounting disk 4 to form the mounting portion 3. The winding block 2 is wound around the winding block 8 in the middle. The elastic cord may be attached as long as it can be wound around a winding block having separate winding blocks on both sides. For example, when the attaching portion is composed of a set of four winding blocks, both ends are It is possible to wrap the elastic cord around either of the two inner winding blocks.

As shown in FIG. 3, the winding blocks 2 constituting the mounting portion 3 are in a very close positional relationship with each other, and a tunnel whose upper surface is opened by the side surfaces 7 of the winding blocks 2 facing each other. It is desirable that a cross section such as The elastic cord 9 is wound so as to be inserted into the gap between the winding blocks 2 facing each other. For example, in FIG.
The simplest method is to use the locking end 10 with the cord end folded in two.
The normal end 11 of the elastic cord 9 is wound from the left side surface and wound around the winding block 8 in the middle so as to be taken out from the right side surface to the outside of the mounting disk 4. It is not necessary to use a through hole as such a winding block. For example, as shown in FIG. 5, the winding block 14 that fills the inside of the winding block of this embodiment is formed of plastic. Good.

Thus, with the elastic cord 9 attached,
When the mounting disc 4 is rotated as a rotary cutting blade, an outward force is applied to the normal end 11 of the elastic cord 9 by the centrifugal force toward the outside of the mounting disc 4, so that the locking end 10 faces the winding end. While being pressed against each of the blocks 2, the winding blocks 2 are sandwiched and held by the folded edge portions 1 of the winding blocks 2. Further, since the mounting portion 3 is provided inside the outer circumference of the mounting disc 4, when the elastic cord 9 hits a stone or the like during rotation,
The elastic cord 9 is wound inside the periphery of the mounting disc 4 and cannot be cut.

In the conventional rotary cutting blade, a knot or the like is provided at the hooking end of the elastic cord to attach the cord.
As in the second embodiment shown in (partially plan view), the locking end 16 is attached to the attachment portion 15 composed of two winding blocks.
The conventional elastic cord can be attached to the rotary cutting blade of the present invention by means of locking the inner end with the normal end on the outside and pulling the entire elastic cord outward by centrifugal force. become. However, in addition to the convenience of being able to attach the elastic cord around the attachment portion composed of three or more winding blocks so that the elastic cord can be attached as it is, the elastic cord can be cut off from the reel and the elastic cord It is preferable that the deviation prevention effect is high, which is an advantage.

[0020]

The rotary cutting blade of the power brush cutter according to the present invention comprises a mounting disk for mounting the power brush cutter, a winding block constituting a mounting portion for mounting the elastic cord, and a convex portion for preventing wear of each portion. If the parts and ribs are made of metal, there is an advantage that they can be integrally formed by pressing, burring, etc. This advantage results in reducing raw material costs, manufacturing costs, and labor costs associated therewith, and lowers the unit price of the rotary cutting blade as a product. As mentioned above, this rotary cutting blade can also be manufactured with strong plastic, and in this case the degree of freedom of molding further expands, all parts can be molded in one step,
It will be more economical.

Furthermore, the rotary cutting blade of the present invention has the advantage that it has a simple structure and can be used by switching between the front and back surfaces. Since the structure is simple, it is easy to maintain and maintain, and it has the advantage that it can be visually checked if it is worn or damaged. It is also convenient that a protective cover can be optionally attached to prevent the cut grass from entering the connecting portion between the power brush cutter and the rotary cutting blade so as to prevent the grass from entering.

In addition to this, the elastic cord can be easily attached while visually confirming it.
One of the advantages is that it is easy for beginners to handle for the first time and easy to handle. In particular, by providing protrusions and ribs so that the mounting disk or the end of the winding block does not become a sharp edged tool due to wear, this point is also easy for the operator to handle, and also safety It can be said to be expensive.

[Brief description of drawings]

FIG. 1 is a perspective view showing a mounting relationship of a rotary cutting blade of a first embodiment to a power brush cutter.

FIG. 2 is a plan view of the embodiment.

FIG. 3 is a sectional view taken along line AA in FIG.

FIG. 4 is a sectional view taken along line BB in FIG.

5 is a cross-sectional view of a plastic winding block corresponding to FIG.

FIG. 6 is a partial plan view of the second embodiment.

[Explanation of symbols]

 1 Folded edge 2 Winding block 3 Mounting part 4 Mounting disk 5 Rib 6 Convex part

Claims (3)

[Claims] 1. An elastic cord mounting portion 3 is formed by combining two or more winding blocks 2 each having a folded edge portion 1,
A rotary cutting blade for a power brush cutter, in which a pair of mounting portions are arranged in the vicinity of the outer circumference of the mounting disk 4 in point symmetry with respect to the central axis hole of the mounting disk 4, and one end of an elastic cord is locked to the mounting portion 3. . 2. A rotary cutting blade for a power brush cutter, wherein a rib 5 is provided on the outer edge of the mounting disk 4 according to claim 1. 3. A rotary cutting blade for a power brush cutter, wherein the mounting disk 4 according to claim 1 is provided with a convex portion 6 higher than the winding block 2.