JPH0841A - Tip saw for bush cutter - Google Patents

Abstract

PURPOSE:To provide a tip saw for a bush cutter capable of effectively jumping small stones, etc., preventing tips from chipping and suppressing the deterioration in cutting quality. CONSTITUTION:This tip saw 1 for a bush cutter is obtained by forming tips 8 and 11 from their plural kinds having different hardnesses, varying the setting angles and protruding heights in the outer peripheral edge directions for each kind of the tips 8 and 11, fixing the tips to recessed parts by brazing and setting the setting angle of at least one of the plural kinds of the tips 8 and 11 at, e.g. 0 or a negative angle to the center line and further the protruding height at a raised level in the tip saw 1 for the bush cutter equipped with the recessed parts for installing the plural tips on the outer periphery of a disklike base metal and respective tips, brazed and fixed to the recessed parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tip saw for a brush cutter used as a cutting blade of the brush cutter.

[0002]

2. Description of the Related Art Conventionally, a brush cutter having an engine is used as a brush cutter used for brush cutting work such as weeds or standing trees, and a tip saw is used as a cutting blade thereof. In this tip saw, generally, a steel plate having a uniform thickness is punched by a press to form a base metal, and a plurality of chip mounting recesses formed on the outer peripheral edge of the base metal are made of cemented carbide chips. Each is brazed and fixed.

[0003]

However, in this tip saw, there is a problem that the tip is easily chipped and the sharpness is deteriorated quickly. That is, since the tip made of cemented carbide is brazed and fixed in the tip mounting recess at a constant angle so that its tip end surface is located on the same circumference, pebbles, etc., may be removed when the tip saw rotates. When it hits, the tip of the chip is chipped. In particular, since the tips of all the chips are brazed at the same angle in the direction of rotation, they are easily chipped by the contact of small stones.

The present invention has been made in view of the above circumstances, and an object thereof is to mow the pebbles and the like, which can effectively bounce off pebbles to prevent chipping of chips and prevent deterioration of sharpness. To provide a tip saw for a machine.

[0005]

In order to achieve such an object, a tip saw for a brush cutter according to claim 1 has a plurality of recesses for attaching tips, which are formed on an outer peripheral edge of a disk-shaped base metal. In a tip saw for a brush cutter, in which the tips are brazed and fixed in the recesses, the tips are formed by a plurality of types of tips with different hardness, and the attachment angle and the protrusion height in the outer peripheral direction are different for each type of tip. Differently,
It is characterized by being brazed and fixed in the recess.

The tip saw according to claim 2 is characterized in that at least one of the plurality of tips has a mounting angle set to zero or a minus angle. Among the plurality of types of chips, the protrusion height of a chip having a low hardness is set to be higher than that of a chip having a high hardness. A tip saw according to a fourth aspect is characterized in that there are two types of tips, one of the tips is made of cemented carbide, and the other tip is made of stellite.

[0007]

First, according to the tip saw for a brush cutter of claim 1, for example, a tip having a low hardness is attached so that the protruding height is increased toward the center line direction of the base metal, and the tip is attached during rotation. Bounce off pebbles. This chip is
Since it has low hardness, it will not be easily chipped by contact with small stones. On the other hand, the tip of the tip having a high hardness and a low protruding height is fixed with its tip facing the direction of rotation, and weeds and the like are cut off by this tip. That is, the tip with high hardness becomes the main blade, and the tip with low hardness becomes the auxiliary blade,
Prevents chipping of the main blade and prevents deterioration of sharpness.

Further, according to the tip saw of the second aspect, for example, by fixing the tip having a low hardness at the same angle as the center line of the base metal or at a negative angle, pebbles and the like can be effectively bounced off. According to the tip saw of claim 3, by making the tip having the low hardness protrude toward the outer peripheral edge direction from the tip having the high hardness, pebbles and the like preferentially hit the tip having the low hardness, and the chip of the high hardness is chipped. Certainly prevented. According to the tip saw of the fourth aspect, the tip having a high hardness is made of cemented carbide and the tip having a low hardness is made of stellite, whereby the inexpensive tip can be effectively used.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view showing a tip saw for a brush cutter according to the present invention. In FIG. 1, a tip saw 1 has a disc-shaped base metal 2. This base metal 2
For example, it is formed into a disk shape with a steel plate such as SK material or SKS material,
A mounting hole 3 for a brush cutter (not shown) is formed in the center portion thereof.

A blade portion 4 is formed on the outer periphery of the base metal 2. A plurality of gullets 5 are formed on the blade portion 4,
As shown in FIG. 2, a chip mounting portion 7 having a chip mounting recess 6 (including a stepped portion) is formed between the gullets 5. The recess 6 of the chip mounting portion 7 is formed at an angle of, for example, A = 15 to 45 degrees with respect to the center line L1 extending from the center of the base metal 2 to the outer periphery, and is made of a cemented carbide in the recess 6. The chips 8 are fitted and fixed by brazing.

Further, a chip mounting portion 9 having a shape slightly different from that of the chip mounting portion 7 is formed at the next position where, for example, three chip mounting portions 7 are continuous. The recess 10 (including the stepped portion) of the chip mounting portion 9 is bored at an angle of B = -5 degrees with respect to the center line L2, and the chip 11 made of stellite is fitted into the recess 6. They are fixed by brazing.

The curve L3 connecting the tip surface 8a of the chip 8 and the curve L4 connecting the tip surface 11a of the chip 11 are
It has a spacing of dimension h. That is, the tip 11 fixed to the concave portion 10 is projected from the tip 8 fixed to the concave portion 6 in the protruding height h in the outer peripheral edge direction of the blade portion 4. Moreover, the chips 8 and 11 are formed in substantially the same shape.

In this tip saw 1, the mounting hole 3 is attached to a brush cutter (not shown) and is rotated in the direction of arrow A in FIG. 2, so that the tip 8 attached in the direction of rotation becomes the main blade. And weeds are cut off. At this time, chip 11
Has its tip surface 11b located at the outermost peripheral edge of the tip saw, so if, for example, pebbles or the like are present, the pebbles etc.
The tip 1 comes into contact with the tip 1 before the tip 8, and the pebbles and the like are splashed by the front surface 11a thereof. Since the tip 11 has low hardness, is soft, and is viscous, it is not easily chipped by contact with small stones or the like.

Since the tip 11 is located at a predetermined interval from the tip 8, the chances that a small stone or the like hits the tip 8 as the main blade is reduced, and the tip 8b of the tip 8 is prevented from being chipped. . The chip 11 also has a front surface 11a.
Also, the tip surface 11b acts on the cutting to some extent.

As described above, in the above-described embodiment, the chips 8 having different hardnesses and different mounting angles and projecting heights,
Since 11 is brazed and fixed at predetermined intervals, it is possible to mow weeds and the like mainly by the tip 8 and bounce off small stones and the like by the tip 11. Thereby, chipping of the tip 8 is prevented, the sharpness of the tip saw 1 is not deteriorated, and the tip saw 1 can be used for a long period of time.

In the above embodiment, the chip 11
The mounting angle B of was set to a negative angle, but the center line L
It is also possible to set two identical angles, that is, B = 0 degree. Even with this setting, the same effect as that of the above embodiment can be obtained. Further, in each of the above embodiments, the chips 8 and the chips 11 are provided at predetermined intervals, but they may be provided alternately, or the chips 8 and the chips 11 may have different shapes.

Further, in the above embodiment, the chips are two types of chips 8 and 11 having different hardness, but three or more types of chips may be used, and the chips 8 and 11 in the above examples may be used. It is needless to say that the materials, the positions and shapes of the chip mounting portions 7, 9 and the recesses 6, 10 are also examples, and various changes can be made without departing from the scope of the present invention.

[0018]

As described above in detail, in the tip saw for the brush cutter of the present invention, a plurality of types of tips having different hardness are fixed by brazing with different mounting angles and projecting heights. As a result, pebbles and the like can be effectively bounced off, and the sharpness of the tip saw can be prevented from decreasing.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a tip saw for a brush cutter according to the present invention.

FIG. 2 is an enlarged plan view of the main part of the same.

[Explanation of symbols]

 1 Tip Saw 2 Base Metal 3 Mounting Hole 4 Blade 5 Galet 6 and 10 Recess 7 and 9 Tip Mounting 8 and 11 Tip

Claims (4)

[Claims] 1. A chip saw for a brush cutter, wherein a plurality of recesses for mounting chips are formed on an outer peripheral edge of a disk-shaped base metal, and the chips are hardened in hardness in a chip saw for mowers in which the chips are brazed and fixed. Different types of chips are used, and the mounting angle and the protruding height in the outer peripheral direction are made different for each type of chip, and the chips are brazed and fixed in the recesses. Tipped saw. 2. A chip saw for a brush cutter according to claim 1, wherein the mounting angle of at least one of the plurality of types of chips is set to zero or a minus angle. 3. The brush cutter according to claim 1, wherein among the plurality of types of chips, a tip having a low hardness is set to have a height higher than that of a tip having a high hardness. Tipped saw. 4. The chip according to claim 1, wherein the chips are of two types, one of which is made of cemented carbide and the other of which is made of stellite. A tip saw for a brush cutter.