JPH0935A - Mowing blade for brush cutter - Google Patents

Abstract

PURPOSE: To provide an economical mowing blade for a brush cutter, hardly chipping the blade tips and capable of manifesting high cutting quality, withstanding the use for a long period if the cutting blades of a grass cutting blades should be broken and sufficiently reducing the exchange frequency of the mowing blade without deteriorating the cutting quality thereof. CONSTITUTION: This mowing blade for a brush cutter is obtained by installing blade parts 3 in valley parts between cutting blades 2 and embedding cemented carbide tip blades 4 having the same thickness as the wall thickness of the mowing blade body 1 in the tip parts of the cutting blades following to the outer periphery of the cutting blades 2 and blade parts 3 of valley parts in the mowing blade 1 for the bush cutter, formed into a circular shape and having the plural cutting blades 2 at the peripheral ends thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grass cutting blade for a brush cutter used for cutting weeds and the like.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, a grass cutting blade of this type has a disk-like shape and is provided with a plurality of cutting blades 6 at the peripheral end of a grass cutting blade body 5. The cutting blade 6 cuts weeds and the like by rotating at high speed. At that time, the sharpness of the cutting edge is likely to be deteriorated due to the mud attached to the weeds, and when the cutting blade 6 comes into contact with an obstacle such as stone, there is a problem that the cutting edge is chipped and the sharpness is significantly decreased. .

[0003]

Therefore, the present applicant has
In order to solve the above-mentioned problems, an application for this type of mowing blade was filed in Japanese Patent Application No. 5-16206. As shown in FIG. 6, this mowing blade has arcuate blade portions 31 continuously provided from the blade portions 21a of the blades in the valley portions of the blades 21 and 21 '. And, by having such a configuration, the following effects are brought about. That is, (a). If the tip of the cutting blade is damaged, the arcuate blade formed in the valley acts as a new cutting blade, and the deterioration of sharpness can be stopped minutely, and one grass cutting blade can be used for a long time. It is economical because you can. The present invention has also been made in view of the actual situation as described, showing a high sharpness that the cutting edge is unlikely to chip, and should withstand long-term use even if the cutting blade of the grass cutting blade is damaged, the sharpness thereof It is an object of the present invention to provide an economical grass cutting blade for grass cutters, in which the number of times of replacement of the grass cutting blade is small and the cost is low.

[0004]

For this reason, according to the present invention, in a grass cutting blade for a brush cutter, which is formed in a disc shape and has a plurality of cutting blades at its peripheral end, the blade is provided in a valley portion between the cutting blades. With the portion provided, at the tip of the cutting blade, along with the outer periphery of the cutting blade and the blade portion of the valley portion, formed, embedded a cemented carbide tip blade having the same thickness as the grass cutting blade body. The first feature is that the cemented carbide tip blade is embedded more inward than the outer peripheral end of the cutting blade, and the second feature is that the rake angle is 0 degree to
The third characteristic is that the angle is 5 degrees.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a plan view of a grass cutting blade for a brush cutter according to the present invention, FIG. 2 is an enlarged sectional view taken along the line AA of FIG. 1, and FIG. 3 is an enlarged perspective view showing a state in which a cemented carbide tip blade is separated from a cutting blade portion. 4, FIG. 4 is a plan view of relevant parts showing a damaged state of the mowing blade, FIG. 5 is a plan view of relevant parts of the conventional mowing blade, and FIG. 6 is a plan view showing the conventional mowing blade.

As shown in FIG. 1, the mowing blade main body 1 is formed in a disk shape. A plurality of saw-tooth-shaped cutting blades 2 and 2'are provided at equal intervals on the circumferential end portion of the grass cutting blade body 1. A blade portion 3 formed in an arc shape is provided in a valley portion between the cutting blade 2 and the adjacent cutting blade 2 '. The blade portion 3 is provided between all the cutting blades 2 and 2 ′, and is formed integrally and continuously with the blade portion 2 a of the cutting blade 2.

As shown in FIGS. 1 to 3, a carbide tip blade 4 is embedded in the tip of the cutting blade 2 and attached by welding. The cemented carbide tip blade 4 has a blade portion 4a formed by grinding with a grinder, which is continuous with the outer periphery of the cutting blade 2 and the blade portion 3 of the valley portion and which follows the inclination angle of the blade portion 3 and 2, the thickness of the cutting blade body is the same as the thickness (that is, the front and back surfaces 2b and 2 of the cutting blade 2).
c and the front and back surfaces 4b and 4c of the carbide tip blade 4 are flush with each other. Further, the cemented carbide tip blade 4 is embedded more inward than the outer peripheral end of the cutting blade 2. This not only makes it difficult for the carbide tip blade 4 to be removed even when it comes into contact with an obstacle, but also in the unlikely event that the carbide tip blade 4 comes off, the outer radius of the grass cutting blade body 1 itself changes. Since it does not, the turning radii do not become uneven and it is difficult for camera shake to occur.

Further, it is desirable that the rake angle of the cutting blade 2 be 0 to 5 degrees, and in this embodiment, it is set to 0 degrees (the cutting blade 2
The straight line portion of the blade portion 2a is located on the radius line of the grass cutting blade main body 1). As a result, the cutting blade 2 abuts the object to be cut almost vertically, so that the cutting resistance is reduced and the labor burden on the operator is reduced. Further, since the cutting blade 2 of the main grass cutting blade is not a combined blade (blades that intersect with each other in alternation) as seen in a conventional saw blade or the like, all the cutting blades 2 are provided on the same plane, After cutting, the cut surface of grass etc. is straight and neat.

This grass cutting blade is attached to a portable type brush cutter and cuts weeds by being rotated at high speed by a drive source such as a motor to show better sharpness than conventional grass cutting blades even in normal use. It is when the cutting blade is broken that the mowing blade is more effective than the conventional one. When the conventional cutting blade shown in FIG. 5 is damaged, the blade portion of the cutting blade 6 is missing, and the sharpness thereof is significantly reduced. In addition, the reduced sharpness increases the resistance force from the object to be cut, and the touch is likely to occur due to vibration, which lowers the workability.

As shown in FIG. 4, when the cutting blade 2 of the grass cutting blade is damaged, a valley portion between the cutting blade 2 and a cutting blade 2'provided adjacent to the cutting blade 2 is formed. The blade portion 3 formed in an arc shape acts as a new small-sized cutting blade, and suppresses deterioration of sharpness due to breakage of the cutting blade 2. The difference in the cutting efficiency becomes larger as the number of damaged parts of the cutting blade 2 increases. Further, compared with the conventional tip saw, the cemented carbide tip blade 4 is hard to come off as described above, and even if it comes off, it is hard to be touched by vibration.

[0011]

The present invention having the above-mentioned constitution has the following excellent effects. (1). When the tip portion of the cutting blade is damaged, the arc-shaped blade portion formed in the valley portion acts as a new cutting blade, and the sharpness can be slightly reduced. (2). It is economical because one blade can be used for a long time. (3). By providing the carbide tip blade, the blade tip is less likely to be damaged and high sharpness can be obtained. (4). Since the cutting resistance with respect to the object to be cut is small, the labor burden on the worker is reduced.

[Brief description of drawings]

FIG. 1 is a plan view of a grass cutting blade for a brush cutter according to the present invention.

FIG. 2 is an enlarged cross section taken along line AA of FIG.

FIG. 3 is an enlarged perspective view showing a state where a carbide tip blade is separated from a cutting blade portion.

FIG. 4 is a main part plan view showing a damaged state of the mowing blade.

FIG. 5 is a plan view of an essential part showing a conventional mowing blade.

FIG. 6 is a plan view showing a conventional mowing blade.

[Explanation of symbols]

 1 cutting blade main body 2 cutting blade 2'cutting blade 2a cutting edge 3 arcuate cutting edge 4 carbide tip blade 4a cutting edge of cemented carbide tip 5 conventional cutting blade 6 cutting blade of conventional cutting blade

Claims (3)

[Claims] 1. A grass cutting blade for a brush cutter, which is formed in a disk shape and has a plurality of cutting blades at its peripheral end portion. The blade portion is provided in the valley between the cutting blades, and the tip portion of the cutting blade is provided. In addition, while forming along the outer periphery of the cutting blade and the blade portion of the valley portion, a cemented carbide tip blade having the same thickness as the thickness of the grass cutting blade main body is embedded, . 2. The grass cutting blade for a brush cutter according to claim 1, wherein the cemented carbide tip blade is embedded more inward than the outer peripheral end of the cutting blade. 3. The grass cutting blade for a brush cutter according to claim 1, wherein the rake angle is 0 to 5 degrees.