JPH063030U - Cutting blade of brush cutter - Google Patents

Abstract

(57) [Summary] [Purpose] A sharp-cutting blade of a brush cutter that does not bounce stones or the like and does not wind grass stems. [Structure] On the outer circumference of the circular cutting blade 10, a small diameter portion 12 is formed on the upper side in the rotation direction and a large diameter portion 14 is formed on the lower side, and a blade portion 20 is connected to each other by a gradually increasing portion 16 and a connecting portion 18. A cutting blade for a brush cutter, wherein the cutting portion is formed continuously, and a groove 22 is formed continuously on the blade portion 20 toward the upper side in the rotation direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cutting blade of a brush cutter.

[0002]

[Prior art]

 The primary concern with the cutting blade of a brush cutter is that the blade wears and sharpens with use. For this reason, the cutting edge must be constantly ground in order to maintain good sharpness. However, many people are reluctant to grind, and more than anything else, skill is required to perform good grinding. In view of such a point, the inventor of the present invention proposes a device in which a groove formed of a peak portion and a valley portion is formed on the cutting edge, and when the cutting edge is worn, a saw blade is formed on the cutting edge. (No. 99725), it is producing a corresponding effect.

[0003]

[Problems to be solved by the device]

 On the other hand, other problems of cutting blades are winding of grass stems and jumping of stones. In both cases, the work efficiency and safety are impaired, so this must be resolved. For this reason, some cutting blades are provided with a wrapping prevention cup or a jump-prevention skirt, but the effect is so great that the structure is complicated and the usability is poor. Absent. The present invention solves these problems and solves these problems by simply changing the shape of the cutting blade.

[0004]

[Means for Solving the Problems]

 Under the above problems, the present invention has a circular cutting blade with a small diameter portion on the upper side in the rotational direction and a large diameter portion on the lower side, which are connected to each other by a gradually increasing portion and a connecting portion. The present invention provides a cutting blade for a brush cutter, wherein the cutting portion is formed continuously, and a groove is formed continuously on the blade portion toward the upper side in the rotation direction.

[0005]

[Advantages] By taking the above means, the valley portion of the groove is thinner than the peak portion, so that it becomes a saw-tooth shape with use, and the sharpness is not deteriorated. Therefore, it is likely that the grass stems will wrap around. In addition, since the blade part gradually changes from the small diameter part to the large diameter part through the gradually increasing part, there is no wall-like part that directly hits the object to be cut, and even if it hits a stone etc., it does not bounce off. Yes.

[0006]

【Example】

 FIG. 1 is a plan view of a cutting blade according to the present invention, and FIG. 2 is a partial cross-sectional side view. The cutting blade 10 is a circular blade, but the small diameter portion 12 is on the upper side in the rotational direction and the diameter is on the lower side. The large portion 14 is formed, and a blade portion 20 that connects the large portion 14 with the gradually increasing portion 16 and the connecting portion 18 is continuously formed. At the portion of the gradually increasing portion 16, a groove 22 that extends toward the upper side in the rotational direction is continuously formed. It is formed. Although FIG. 3 is a front view of the groove 22, the peaks 22a and the valleys 22b are alternately repeated in this manner.

In the present example, the connecting portion 18 has a shape in which the radius is gradually reduced (however, it is preferable that the width is shorter than the gradually increasing portion 16), but in addition to this, the small diameter portion 12 is provided immediately below the large diameter portion 14. May be formed like a vertical cliff, or the large-diameter portion 14 may overhang on the small-diameter portion 12. Further, both the gradually increasing portion 16 and the connecting portion 18 are formed in a convex arc shape, but may be in a linear shape in addition to this. Further, the groove 22 may be formed in such a manner that the deviation angle α formed by the portion facing the gradually increasing portion 16 and the normal line (radius) is positive, that is, the groove 22 is directed toward the upper side in the rotational direction. In addition, the shape of the groove 22 is not limited to a straight line or a circular arc, and the formed portion does not need to be deep in the center of the cutting blade 10, and may be formed at least to a range smaller than the small diameter portion 12.

The side shape of the cutting blade 10 may be a flat plate, but may be one in which the outer peripheral portion is bent upward as shown in FIG. When curved in this way, it has the advantages that it does not bite into the ground when in use, and that it is easy to mow grass that grows on the slope.

FIG. 4 is a plan view of the blade portion 20, but when the cutting blade 10 is used, the valley portion 22b of the thin groove 22 is worn earlier than the mountain portion 22a, and the result is as follows. As a saw blade. As a result, the sharpness is improved, the grass stem can be cut with a light force, and the grass stem does not wind around the rotating part. In addition, when the sharpness decreases, the tip of the blade 20 can be ground by applying it to a hard object, for example, a concrete surface or the like and rotating it, and no special grinding is required.

By the way, since the blade 20 repeatedly acts on the object to be cut such as grass and stalks from the small-diameter portion 12 to the gradually increasing portion 16, it hits the object at a stretch like a conventional blade and gives a large resistance. There is no part to generate. Therefore, for example, even if a stone or the like hits the outer periphery of the blade portion 20 due to use, the force for bouncing the stone portion 20 is weak, and the cutting blade 10 is less likely to be damaged.

FIG. 5 is a plan view showing another embodiment of the cutting blade according to the present invention. In this embodiment, the large diameter portion 14 is provided with the straight portion 14a having the same radius. According to this, the impact of stones and the like is further reduced and the impact is small.

FIG. 6 is a plan view showing another embodiment of the cutting blade according to the present invention, and FIG. 7 is a back view. In this embodiment, the gradient of the gradually decreasing connecting portion 18 is made slightly gentle, It can be used on both sides. Along with this, the side surface has a flat plate shape, and the grooves 22 are formed on the front and back sides. The example has an advantage of prolonging the life.

[0013]

[Effect of device]

 As described above, according to the present invention, since the groove formed in the blade portion becomes a saw blade with use, the sharpness is not lowered forever, and the grass stem is not wrapped around the rotating portion. Further, the grinding need only be applied to a hard object and rotated, and no special grinding is required. Furthermore, since it acts on the large diameter part from the small diameter part through the gradually increasing part, there is no part that hits the work piece at a stretch like the conventional cutting blade, and bounces off stones and the cutting blade is damaged. Is less and safe.

[Submission date] June 8, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

[0005]

[Action]

 By taking the above means, since the valley portion of the groove is thinner than the mountain portion, it becomes a saw blade shape as it is used, and the grass stem is cut as if with a saw blade, improving the cutting performance. And does not reduce the sharpness. Therefore, grass stems and the like do not wrap around. In addition, since the blade part gradually changes from the small diameter part to the large diameter part through the gradually increasing part, there is no wall-like part that directly hits the object to be cut, and even if it hits a stone, etc. Do not fly.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

FIG. 4 is a plan view of the blade portion 20. When the cutting blade 10 is used, the valley portion 22b of the thin groove 22 is worn earlier than the mountain portion 22a, and as a result, As a saw blade. This makes it possible to cut the grass stalks with a rotating saw and sickle, so that the grass stalks can be cut with a light force, and the grass stalks do not wrap around the rotating part. When the sharpness decreases, the tip of the blade portion 20 can be ground by bringing it into contact with a hard object, for example, a concrete surface or the like, and the grinding can be performed, without requiring special grinding. Of course, the saw blade is formed from the beginning.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

FIG. 6 is a plan view showing another embodiment of the cutting blade according to the present invention, and FIG. 7 is a back view. In this embodiment, the gradient of the gradually deforming connecting portion 18 is slightly gentle. It can be used on both sides. Along with this, the side surface has a flat plate shape, and the grooves 22 are formed on the front and back sides. This example has an advantage of prolonging the life. Alternatively, the groove 22 may be formed by forming the blade portion 20 with a corrugated plate. In this case, it is necessary to make the tip of the blade portion 20 into a saw blade by taking a surface, but there is an advantage that the groove 22 can be easily formed.

[Brief description of drawings]

FIG. 1 is a plan view of a cutting blade.

FIG. 2 is a partial sectional side view of a cutting blade.

FIG. 3 is a front view of a groove of a cutting blade.

FIG. 4 is a main part plan view showing a usage state of a cutting blade.

FIG. 5 is a plan view of a cutting blade.

FIG. 6 is a plan view of a cutting blade.

FIG. 7 is a rear view of the cutting blade.

[Explanation of symbols]

 10 Cutting blade 12 Small diameter part 14 Large diameter part 16 Gradual increase part 18 Connection part 20 Blade part 22 Groove

Claims (3)

[Scope of utility model registration request] 1. A circular cutting blade is formed with a small diameter portion on the upper side in the rotation direction and a large diameter portion on the lower side on the outer circumference of a circular cutting blade, and a blade portion connected to each other by a gradually increasing portion and a connecting portion is continuously formed. Along with
A cutting blade for a brush cutter, wherein a groove is formed continuously on the blade portion toward the upper side in the rotation direction. 2. A cutting blade for a brush cutter, wherein the outer peripheral portion of the cutting blade according to claim 1 is curved upward. 3. A cutting blade for a brush cutter, wherein the cutting blade according to claim 1 is a flat plate, and a groove on the back surface of the blade portion is formed continuously toward the upper side in the rotation direction.