JPH09220014A - Cutter cord containing copper wire for rotary mowing machine - Google Patents

Abstract

PURPOSE: To provide a cutter cord for the rotary mowing machine which is sharp, small in abrasion, and less broken. CONSTITUTION: A thin metal strand wire 2 or metal bundle wire 5 which has proper hardness and is hard to break is put in the central part of the cutter cord 1 made of a synthetic resin. Consequently, the synthetic resin is used in combination to coat the thin strand wire 2 or metal bundle wire 5 or by integral molding, etc., so much larger effect is obtained as compared with the individual use of them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin thread-like mowing blade (cutter cord) which is attached to a rotary mowing machine for use in cutting off weeds or the like, or a metal strand, or The present invention relates to a rotary mower cutter cord containing a metal bundle.

[0002]

2. Description of the Related Art Conventionally, rotary mowers having a copper disk-shaped rotary blade are widely used, but if they come into direct contact with a human body, they are extremely dangerous and hit obstacles. There is a risk of breaking and scattering, and it cannot be used on uneven terrain, on the wall, at the root of a plant, etc. Therefore, although a synthetic resin cutter cord has been put into practical use at present, there is a drawback that the cutter cord is heavily worn and has poor sharpness, and that grass-like weeds are difficult to cut.

A device in which a steel wire is coated with plastic in order to eliminate the drawbacks of the cutter cord made of synthetic resin (Shokai 64-13923, Shokai 61-69930).
However, since the lawn mower rotates at high speed, it has not been put into practical use due to early breakage due to material fatigue.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the drawbacks of conventional cutter cords with poor sharpness and high wear, and provides a cutter cord with good sharpness, low wear and less breakage. It is intended.

[0005]

According to the present invention, a thin metal twisted wire 2 or a thin metal bundled wire 5 having suitable hardness and a characteristic of being hard to break is provided at the center of a cutter cord 1 made of synthetic resin. It is a cutter cord with the inserted structure.

[0006]

The operation will be described with reference to FIG. FIG. 3 shows the state of the cutter cord after use. As it is used, the tip part 3 of the conventional cutter cord is torn into a broom as shown in FIG. 3A.
Alternatively, it becomes needle-shaped as shown in FIG. 3B. In any case, it is in a state where only synthetic resin is fluffy. The present invention does not do so, and since the metal strand 2 has a lower degree of wear than the synthetic resin cutter cord 1, the tip 4 of the metal strand naturally protrudes from the resin portion during use. As shown in Fig. 3C, the thin metal wires are scattered.
Moreover, when the metal wire bundle 5 is inserted, the state becomes as shown in FIG. 3D. The sharpness of the cutter cord of the rotary mower is largely determined by the hardness of the tip of the rotating cutter cord and the magnitude of centrifugal force and inertial force. That is, like the conventional cutter cord, the tip 4
Contrary to the fact that it becomes worn and becomes fluffy, and the sharpness deteriorates, in the cutter cord with metal wire of the present invention, the wear degree of metal is lower than that of synthetic resin, so the tip during use Since a plurality of hard thin metal wires come out in the part, the sharpness does not deteriorate, and the overall wear also decreases. Since the metal wire has a specific gravity of 5 to 8 times that of the synthetic resin, the average specific gravity of the cutter cord is high, the centrifugal force and inertial force during rotation are large, and it strongly hits the grass and becomes sharp. However, in current metal wires such as steel wires, it is technically and economically difficult to avoid the drawback of being easily broken due to material fatigue as compared with wires made of synthetic resin such as nylon. In the present invention, by using the metal twisted wire 2 or the metal bundled wire 5 that is thinner than the cutter cord 1, a large radius of curvature can be taken in comparison with each metal wire diameter in the bending motion that occurs during mowing. A cutter cord that reduces material fatigue and is hard to break when cutting grass is obtained.

[0007]

[Examples] As a method of inserting the center portion of the cutter cord 1, a metal strand, or a metal bundle wire, there is a method of coating by extrusion molding.

In order to prevent breakage, it is desirable that the thickness of the metal wire is 1/7 or less of the thickness of the cutter cord 1, and in order to improve the sharpness, a twisted wire or a bundled wire is used. The thickness is preferably 1/5 or more.

Nine kinds of samples shown in FIG. 4 were produced, and as a comparative material, a single wire covered with a nylon tube (J), a nylon cord (K), and a steel stranded wire (L) were used.
Mowing was carried out according to the type. The results are shown in FIG. 5. The comparative material J was immediately broken, the comparative material K was not sufficient in terms of sharpness, and the comparative material L was in a state in which it could not be used in a variety immediately after use. The situation after the use of the comparative material J is shown in FIG. 7, and that of the comparative material L is shown in FIG.
Prototype sample I is slightly sharper than Comparative material K, but inferior to the other prototype materials. A
After repeated use for about 10 minutes, disconnection sometimes occurred. The sharpness of the other samples was close to that of a metal disk cutter, and the wire breaking was comparable to that of nylon cords.

The situation after using the prototype is shown in FIG.
As shown in FIG. 3C, the tip portion was in a disproportionate state, and the sharpness was further improved from the initial stage of use.

[0011]

EFFECTS OF THE INVENTION If only a stranded steel wire is used as the cutter cord, it will not be able to be continuously used because it will be discolored immediately. If the steel wire is coated with a synthetic resin, etc. When used, it is difficult to break, but has drawbacks such as poor sharpness and fast wear. The present invention provides a cutter cord with good sharpness, hard to be broken, and less wear by covering a metal stranded wire which is not easily broken or a metal bundle wire with a synthetic resin such as nylon. .

[0012]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a cutter cord with a twisted metal wire.

FIG. 2 is a sectional view of a cutter cord with a bundle of metal wires.

FIG. 3 is an explanatory view of the state of the tip portion after the start of use. A: An example in which a conventional cutter cord has a broom shape. B: An example in which a conventional cutter cord is needle-shaped. C: An example of a cutter cord with a twisted wire. D: An example of a cutter cord with a bundle of metal wires.

FIG. 4 is a detailed list of prototypes.

[Fig. 5] A list of results of use of the prototype.

FIG. 6 is a state after using the cutter cord with the steel twisted wire.

FIG. 7 shows a state after using the steel cord-containing cutter cord.

FIG. 8 shows a state after using a steel stranded wire as a cutter cord.

[0013]

[Explanation of symbols]

 1: Cutter code. 2: Metal stranded wire. 3: The tip of the cutter cord. 4: The tip of the stranded wire. 5: Metal bundle wire. 6: The tip of the metal wire bundle.

[Procedure amendment]

[Submission date] October 31, 1994

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Fig. 6

[Correction method] Change

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FIG. 6

[Procedure amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction contents]

FIG. 7

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] Fig. 8

[Correction method] Change

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[Figure 8]

Claims (2)

[Claims] 1. A thin metal twisted wire (2) or a thin metal bundle wire (5) at the center of a synthetic resin cutter cord (1).
A cutter cord with a steel wire for a rotary mower characterized by containing 2. The cutter cord with a steel wire for a rotary mower according to claim 1, wherein an iron wire, a rope, or a stainless steel wire is used as the metal wire.