KR101584197B1 - A arc type blade for bush cutting machine - Google Patents

Abstract

An arc-shaped grass cutter blade (100) according to the present invention includes a center portion (110) formed with a rotor connecting hole (115) at the center thereof, The blade 125 has an arc-shaped cutout 120. The blade 125 has an arc-shaped cutout 120. The blade 125 has a point symmetrical with respect to the center of the rotor connection hole 115, .

Description

{Arc type blade for bush cutting machine}

The present invention relates to an arc-shaped grass cutter blade.

Conventionally, a tool such as a sickle was used when removing weeds from a rural area or performing a mowing operation at the time of sowing. However, in order to efficiently remove weeds, a mower that rotates a power blades has been used. As a result, large areas of weeds and vines can be removed in a short time.

The types of blades used in the above-mentioned lawn mower include various types of blades such as two-tooth blades, nylon cutters, and circular saw blades. Of these, the most commonly used is a two-degree-of-day. 2 Donald is a two-edged blade that performs mowing and has a straight line.

FIG. 1 is a conceptual diagram showing a principle in which a blade cuts an object. 1, the look of the principles of the blade cutting, jareumyeo an object with a force (F) Synthesis of a constant pressing force (F ₁₎ and a pressing force (F _2), wherein the pressing force (F ₂₎ The main role is to reduce the resistance of objects that interfere with the movement of the blade by destroying the tissue of the object by a sharp blade.

FIG. 2 is a conceptual diagram showing a principle of a conventional straight-type two-tooth blade cutting a mowing object. A, arcuate lawn mower edge is formed in a rotational direction and scan line, the force (F _1), that is, albeit weak, and forces the main component hitting the target pressing force (F ₂₎ hitting the same direction of rotation as shown in Figure 2, the And finally the force (F) acts on the object.

As described above, the synthesized force F can efficiently cut the object to be cut when it is most appropriately combined according to the amount of movement of the blade transmitted from the lawn mower, the sharpness of the arc-shaped lawn mower blade, and the kind of the lawn mower.

Particularly, the objects to be cut by the circular arc cutter blade are mostly fibrous and woody, and the proper mechanical relationship between the beating force (F ₁ ) and the pushing force (F ₂ ) as the rotating direction is required, It is closely related to the cutting angle.

Fig. 3 is a plan view of a straight two-conical flyer according to the prior art. 3, the linear second dovetail 300 according to the related art is formed in a shape of an oblique line so that its width becomes narrower toward both ends, and the blade 350 is formed in a straight line, It applies a diagonal force to the object. However, the linear two-cone dovetail 300 according to the prior art needs to be improved in terms of the mechanical efficiency of rotation.

With both ends actual mowing angle at which the straight line 2 donal 300 according to the prior art in accordance with the rotation increasing abruptly larger structure _{(θ 3> θ 2> θ} 1) because, pressing force (F ₂₎ hit from the same direction of rotation There is a problem of a mechanical structure which is excessively dependent on the force F ₁ .

In particular, the problem of the mechanical structure that arises as the straight second dovetail 300 cuts the objects to be cut is that the length of the blade 350 where the straight second dovetail 300 contacts the object to be cut is shortened The time is shortened, and the tissue of the object to be cut is not efficiently cut. In addition, since the straight two-pointed donor 300 can not efficiently cut the tissue of the object to be cut, there is a problem that the object to be cut is a large resistance to the rotational motion of the straight two-pointed dovetail 300, .

In addition, since the angle of the conventional straight two-cone dovetail 300 is excessively increased toward both ends, a phenomenon in which the object to be cut which does not break is wound around the cutter blade often occurs, which reduces the efficiency of the mowing work.

Another problem with the conventional linear two-cone donor 300 is that it is difficult to form a saw blade on a grass blade blade because the grass blade and the bay of the object to be weighed have a large angle and can not function as a saw blade even if the blade is formed.

KR 20-0334759 Y1

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the conventional art described above. One aspect of the present invention is to provide a knife cutter which can cut a mowing object efficiently by solving a structural problem of a conventional straight- It is intended to provide an arc-shaped grass mower blade.

Another aspect of the present invention is to extend a length of contact between a blade of an arc-shaped grass mower blade and a mowing object, and to increase the time for cutting the mowing object, thereby dispersing a force acting on the blade, It is intended to provide an arc-shaped grass mower blade.

The arc-shaped grass cutter blade according to an embodiment of the present invention includes a center portion formed with a rotor connecting hole at the center thereof, and a blade portion extending from the center portion to both sides and having a width narrower toward both ends to meet a rim, Includes an arc-shaped cut portion, and is formed in point-symmetry with respect to the center of the rotor connection hole.

In the arc-shaped grass cutter blade according to the embodiment of the present invention, the angle between the rotation direction of the blade and the tangent line of the blade is constant along the blade.

In the arc-shaped grass cutter blade according to the embodiment of the present invention, the angle between the rotation direction of the blade and the tangent line of the blade increases along the blade toward the end of the blade.

In the arc-shaped grass cutter blade according to the embodiment of the present invention, the largest angle (maximum angle) among the angles between the rotational direction of the blade and the tangent line of the blade is defined as A, When the angle (minimum angle) is defined as B, the value of (AB) / (B) is more than 0 and not more than 0.5.

In the arc-shaped grass cutter blade according to the embodiment of the present invention, grooves recessed inward of the cut portion are periodically formed on the edge of the cut portion.

In the circular knife blade according to the embodiment of the present invention, the blade has upper and lower edges of the cut portion extending to one side from the central portion and upper and lower edges of the cut portion extending to the other side from the center portion, Grooves are periodically formed.

In the circular knife blade according to the embodiment of the present invention, the blade has an upper edge of the cut portion extending to one side from the central portion and a lower edge of the cut portion extending to the other side from the center portion in the inner direction of the cut portion The recessed grooves are periodically formed.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to that, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may properly define the concept of the term in order to best explain its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to the present invention, since the knife blade extends in an arc-like shape, the mowing work can be performed with relatively low power, and the contact angle between the blade and the mowing object is small and cut into diagonal lines. Therefore, There is also an effect that the grass cutter blade rotates while pushing the grass cut object, thereby preventing the grass cut object from being wound around the grass cutter blade.

In addition, according to the present invention, since the knife blade extends in an arcuate shape and the angle of contact between the blade and the mowing object is small, the mowing object is pushed and cut so that a saw blade is formed on the blade, There is an advantage.

Further, according to the present invention, it is possible to drive the arc-shaped grass cutter blade at a relatively low rotational speed, and to realize the same cutting efficiency, so that a small power is consumed, thereby energy can be saved, noise can be reduced, It is possible not only to reduce air pollution due to combustion, but also to extend the lifetime of lawn mowers.

Further, according to the present invention, since the arc-shaped grass cutter blade is driven at a relatively low rotational speed, the vibration generated in the handle portion is reduced to reduce the shaking motion and the pushing force is strong, There is an advantage that a safety accident that damages the operator can be prevented in advance.

1 is a conceptual diagram showing a principle of cutting a target by a blade,
FIG. 2 is a conceptual view showing a principle of cutting a cutting object by a blade of a conventional straight two-tooth blade,
3 is a plan view of a conventional straight-type two-conical-
4 is a plan view of an arc-shaped grass cutter blade according to an embodiment of the present invention,
Fig. 5 is a perspective view of the arc-shaped grass cutter blade shown in Fig. 4,
6 is a plan view comparing an arc-shaped grass cutter blade according to an embodiment of the present invention and a conventional straight-
FIGS. 7A and 7B are plan views showing a contact angle between a blade of an arc-shaped grass mower blade and a mowing object according to an embodiment of the present invention;
FIGS. 8A to 8C are conceptual diagrams comparing the principle of mowing of an arc-shaped mower blade according to an embodiment of the present invention with the principle of mowing of a conventional linear two-tooth moon, and FIGS.
FIGS. 9A to 9C are plan views showing saw blades formed on a blade of an arc-shaped grass cutter blade according to the present embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The objectives, specific advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. Also, the terms "first "," second ", and the like are used to distinguish one element from another element, and the element is not limited thereto. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the present invention, detailed description of related arts which may unnecessarily obscure the gist of the present invention will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 is a plan view of an arc-shaped grass cutter blade according to an embodiment of the present invention, and FIG. 5 is a perspective view of an arc-shaped grass cutter blade shown in FIG.

4 to 5, the arc-shaped grass cutter blade 100 according to the present embodiment includes a center portion 110 formed with a rotor connecting hole 115 at the center thereof, The blade 125 is formed on the rim of the blade 125. The blade 125 includes a cutout 120 extending in a circular arc shape and the blade 125 is formed on the center of the rotor connection hole 115 And are formed in point symmetry.

The arc-shaped grass cutter blade 100 according to the present embodiment includes a cutting portion 120 extending to both sides of the center portion 110 and the center portion 110 as a whole. Here, the central portion 110 and the cut portion 120 may be integrally formed. Specifically, the central portion 110 is formed at the center with a rotor connecting hole 115 to which the rotor of the lawn mower is coupled. Further, the cut portion 120 substantially plays a role of cutting the object to be cut. Here, the cut portion 120 extends to both sides from the center portion 110, and the width becomes narrower toward both ends, and the upper and lower edges meet. At this time, a blade 125 is formed on the upper edge and the lower edge. Further, the blade 125 formed on the upper edge and the lower edge extends in an arc shape. This knife blade 125 can cut the object to be cut while rotating by the rotational force of the rotor. In addition, the arc-shaped grass cutter blade 100 is formed in a point-symmetrical fashion with respect to the center of the rotor connecting hole 115 as a whole. Therefore, the circular knife blade 100 can be used in the same manner as the knife blade 125 even when turned over.

As shown in FIG. 6, the arc-shaped grass cutter blade 100 according to the present embodiment is formed in an arc shape so as to have a wide width and a curvature as compared with the conventional straight two-cone dovetail 300, The knife blade 125 of the grass cutter blade 100 is longer than the blade 350 of the conventional straight two-tooth blade 300.

In addition, the knife blade 125 of the arc-shaped grass cutter blade 100 according to the present embodiment is generally smaller in contact angle with the object to be cut than the knife 350 of the conventional straight type 2-dole blade 300. Here, the contact angle between the blade 125 and the object to be cut can be defined as an angle between the rotation direction of the blade 125 and the tangent of the blade 125, as shown in FIGS. 7A to 7B. On the basis of this definition, when comparing the arc-shaped grass cutter blade 100 according to the present embodiment of the substantially similar size to the conventional straight-type two-tooth cutter, the blade 125 of the circular cutter blade 100 according to the present embodiment, The contact angle between the blade 350 of the conventional straight type 2 dovetail 300 and the object to be cut (see FIG. 3) is 80 degrees or less, while the contact angle between the objects (see FIGS. 7A to 7B) is 50 degrees or less.

In addition, since the knife blade 125 of the arc-shaped grass cutter blade 100 according to the present embodiment is formed in an arc shape so as to have a curvature, it can be manufactured to variously adjust the contact angle with the object to be cut.

7A, the arc-shaped grass cutter blades 100 according to the present embodiment are arranged such that the blade 125 moves along the blade 125 toward the end of the blade 125, The angle between tangents can increase (θ ₃ > θ ₂ > θ ₁ ). However, the angle between the rotation direction of the blade 125 and the tangent of the blade 125 does not increase sharply. For example, at any three points of the blade 125, the angle between the direction of rotation of the blade 125 and the tangent of the blade 125 is 44 degrees (? ₃ ), 37 degrees (? ₂ ), and 30 (? ₁ ). That is, the largest angle (maximum angle) is 44 degrees (? ₃ ) and the smallest angle (minimum angle) is 30 degrees (? ₁ ). Therefore, dividing the difference between the maximum angle and the minimum angle by the minimum angle ((maximum angle - minimum angle) / minimum angle) is about 0.47.

3, the conventional straight type 2 dovetail 300 moves along the blade 350 and moves toward the end of the blade 350 until the rotation direction of the blade 350 and the tangent line of the blade 350 (Θ ₃ > θ ₂ > θ ₁ ). For example, at any three points of the blade 125, the angle between the direction of rotation of the blade 125 and the tangent of the blade 125 is 75 degrees (? ₃ ), 61 degrees (? ₂ ), and 35 degrees (? ₁ ). That is, the largest angle (maximum angle) is 75 degrees (? ₃ ) and the smallest angle (minimum angle) is 35 degrees (? ₁ ). Therefore, dividing the difference between the maximum angle and the minimum angle by the minimum angle ((maximum angle - minimum angle) / minimum angle) is about 1.14.

(Maximum angle-minimum angle) / minimum angle value means that the deviation of the angle is smaller as the size is smaller. In this embodiment, the maximum angle-minimum value of the blade 125 of the arc- Angle / minimum angle value is significantly lower than that of the conventional straight-line type 2-doo (maximum angle-minimum angle) / minimum angle value. As described above, when the (maximum angle-minimum angle) / minimum angle value is small, it is possible to effectively cut the object to be cut by appropriately combining the hitting force F ₁ and the pushing force F ₂ . In order to properly combine the striking force (F ₁₎ and a pressing force (F _2), the blade 125 of the arcuate lawn mower day 100 according to this embodiment (the maximum angle-minimum angle) / minimum angle value It is preferably more than 0 and not more than 0.5.

7B, the arc-shaped grass cutter blade 100 according to the present embodiment is arranged so that the blade 125 moves along the blade 125 toward the end of the blade 125, The angle between the tangential lines can be constant (? ₃ ?? ₂ ?? ₁ ). For example, at any three points of the blade 125, the angle between the direction of rotation of the blade 125 and the tangent of the blade 125 is 28 degrees (? ₃ ), 28 degrees (? ₂ ), and 28 (? ₁ ). In this case, if the difference between the maximum angle and the minimum angle is divided by the minimum angle ((maximum angle - minimum angle) / minimum angle), the value becomes about zero. When the angle between the rotation direction of the blade 125 and the tangent to the blade 125 is constant, the ratio of the hitting force F ₁ to the pushing force F ₂ is constant at all portions of the blade 125 And is suitable for removing rough coarse objects, and particularly, it is suitable for removing rough coarse objects such as scarf by forming a saw blade on the blade 125. [ However, as described above, the fact that the angle between the rotational direction of the blade 125 and the tangent of the blade 125 is constant does not mean that it is mathematically identical, Is used to mean a change in a slight angle caused by a machining error or the like that occurs.

The "first principle" in which the blade 125 of the circular knife blade 100 according to the present embodiment cuts the object to be cut reduces the angle between the rotation direction of the blade 125 and the tangent line of the blade 125, Thereby extending the length of contact between the knife blade 125 and the object to be cut according to the rotation of the arc-shaped grass cutter blade 100. Therefore, the blade 125 pushes the tissue of the object to be cut to easily break the tissue of the object to be cut, thereby reducing the resistance to the rotation of the circular-type grass cutter blade 100.

The object of mowing acts as a kind of resistance that interferes with the rotation of the arc-shaped grass mower blade 100. Therefore, in order to overcome such resistance, the pushing force (F ₂ ) is strengthened to break the tissue of the object to be cut with a lot of fibrous material and woody material, so that the arc-shaped grass cutter blade 100 can be more easily rotated, Can be saved. As a result, if the conventional linear two-cone dovetail 300 is a principle that severely rely on the impact force F ₁ to cut the object to be cut, the knife blade 125 of the arc-shaped grass cutter blade 100 according to the present embodiment has a beating force F ₁ ) and the pushing force F ₂ are appropriately combined to cut the object to be cut.

The "second principle" in which the knife 125 of the circular knife blade 100 according to the present embodiment cuts the object of mowing is to increase the contact time between the blade 125 and the object to be cut, It is a principle that distributes power. In this case, even if the momentum acting on the arc-shaped grass cutter blade 100 does not change, the force acting on the arc-shaped grass cutter blade 100 is inversely proportional to the contact time between the blade 125 and the object to be cut Therefore, when the contact time between the blade 125 and the object to be cut is increased, the force acting on the circular-type grass cutter blade 100 decreases. Therefore, it is possible to reduce the pulsation of the coarse mowing object on the arc-shaped grass mower blade 100.

As a result, the arc-shaped grass cutter blade 100 according to the present embodiment can achieve the same cutting efficiency even if it rotates at a lower speed than the conventional straight-type 2-dole blade 300. Conversely, since the conventional linear 2-dovetail 300 has to rotate at a relatively high speed in order to reduce pulsation, there is a disadvantage that a lot of power is consumed in the lawn mower.

8A to 8C are conceptual diagrams comparing the principle of sowing of an arc-shaped grass-cutter blade according to an embodiment of the present invention with that of a conventional straight-line-type sowing dovetail blade, The difference of the donor 300 can be clearly confirmed.

The cutting object 200 is cut at the initial position where the blade 125 of the arc-shaped grass cutter blade 100 according to the present embodiment first makes contact with the object 200 to be cut, assuming that there is no motion of the object 200 to be cut one (see Figure 8a) of length d ₁ to the last position, the cutting blade 350, the mowing object 200 and the mowing object in a first position contacting the first 200 of a conventional linear 2 donal 300 last d ₂ is greater than the length from the position (see FIG. 8b). The blade 125 of the arc-shaped grass cutter blade 100 according to the present embodiment has a length d ₁ from the initial position where the cutting object 200 first contacts with the cutting target 200 to the last position where the cutting target 200 is cut, Is relatively long. Therefore, the arc-shaped grass cutter blade 100 according to the present embodiment can easily cut the grass-cut object 200 by pushing it. This is because the blade 125 of the arc-shaped grass cutter blade 100 according to the above- Proves the "first principle" of cutting the mowing object 200.

The rotation angle? ₁ of the arc-shaped grass cutter blade 100 according to the present embodiment until the blade 125 cuts the grass 200 is the same as the rotation angle? ) Is larger than &thetas; ₂ . As a result, it can be seen that the blade 125 of the arc-shaped grass mower blade 100 according to the present embodiment has a relatively long contact time with the mowing object 200. Accordingly, since the arc-shaped grass mower blade 100 according to the present embodiment disperses the force acting on the blade 125 by increasing the time for cutting the mowing object 200, it is easy to perform the mowing operation even when rotating at a relatively low speed The pulsation acting on the arc-shaped grass cutter blade 100 can be reduced. This proves the "second principle" in which the blade 125 of the arc-shaped grass cutter blade 100 according to the present embodiment cuts the object 200 to be cut.

In addition, as shown in FIG. 8C, the arc-shaped grass cutter blade 100 according to the present embodiment cuts the object 200 to be cut obliquely, so that the object 200 is cut while being pushed out of the radius of rotation. Therefore, the length d ₃ from the initial position where the object 200 is first contacted to the last position where the object 200 is cut is longer, and the rotation angle ? ₃ ) is also increased, the coarse object 200 can be cut efficiently.

In addition, the arc-shaped grass cutter blade 100 according to the present embodiment is a method in which the knife blade 125 is formed in an arcuate shape and the contact angle with the object to be cut is small (see FIGS. 7A to 7B) , And by forming saw blades on the blade 125, it is easy to cut rough and hardly cut objects. On the contrary, the conventional linear two-cone tooth 300 has a large contact angle with the object to be cut (see FIG. 3), and even when the saw blade is formed on the blade 350, the utility of the saw blade is low.

In this connection, FIGS. 9A to 9C are plan views showing saw blades formed on a blade of an arc-shaped grass cutter blade according to the present embodiment.

9A to 9C, grooves 127 recessed inwardly of the cutouts 120 may be periodically formed on the upper and lower edges of the cutouts 120 extending to both sides of the center portion 110 . That is, saw blades can be formed on all four blades 125 formed on the arc-shaped grass cutter blade 100. At this time, the size of the recessed groove 127 may be variously formed. For example, as shown in Fig. 9A, the grooves 127 are formed to be large in size, so that the burrs and the like can be easily cut. Alternatively, as shown in Fig. 9B, the grooves 127 may be formed to be small in size to cut various kinds of objects to be cut and used for a long period of time while regenerating the grass cutter blades 100 when the arc-shaped grass cutter blades 100 are worn .

9C, only the upper edge of the cut portion 120 extending from the central portion 110 to one side and the lower edge of the cut portion 120 extending from the central portion 110 to the other side are provided on the inner side of the cut portion 120 Grooves 127 may be periodically formed. That is, the saw blade can be formed only on two symmetrical blades with respect to the center of the rotor connection hole 115 of the four blades formed on the circular-blade grass blade 100.

The arc-shaped grass cutter blade 100 according to the present invention can perform a mowing operation with a lower power than the conventional straight-type dovetail blade 300, and the blade 125 of the arc-shaped grass cutter blade 100 has a contact angle with the object to be cut It is possible to easily remove rough grass or scarf by applying various types of saw blades.

In addition, since the arc-shaped grass cutter blade 100 according to the present invention reduces the contact angle with the grass cut object while pushing the grass cut object, the grass cut object such as the vine plant is prevented from being wrapped around the grass cutter. So that the efficiency of the work can be increased. On the other hand, in the conventional straight type 2 dovetail 300, since the angle of contact increases dramatically toward both ends of the blade, the uncut object is often wound around the cutter blade, which makes it difficult to remove the wound object. Work efficiency is also low.

Also, since the arc-shaped grass cutter blade 100 according to the present invention is driven at a relatively low rotational speed, the same cutting efficiency can be realized, so that a small power is consumed, energy can be saved, and noise can be reduced And can reduce the air pollution due to the combustion of the fuel as well as extend the life of the mowers. In addition, since the arc-shaped grass cutter blade 100 according to the present invention is driven at a relatively low rotational speed, the vibration generated in the handle portion is reduced to reduce the shaking motion, and the pushing force is strong, It is possible to prevent a safety accident that damages the operator by pushing.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It is obvious that the modification or improvement is possible.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: Circular cutter blade day 110: center
115: rotor connection hole 120:
125: blade 127: groove
200: a mowing object 300:

Claims (7)

A center portion having a rotor connecting hole formed at its center; And
And a cutting edge is formed on the edge of the cutting edge, wherein the cutting edge is formed in a circular arc shape;
Lt; / RTI >
The rotor connection hole being formed in point-symmetry with respect to a center of the rotor connection hole,
The angle between the rotational direction of the blade and the tangent of the blade increases along the blade toward the end of the blade,
Wherein an angle between a rotation direction of the blade and a tangent line of the blade is 50 DEG or less,
(Maximum angle) among the angles between the rotation direction of the blade and the tangent line of the blade is defined as A, and the smallest angle (minimum angle) is defined as B,
(AB) / (B) value of more than 0 and less than or equal to 0.5.
delete delete delete The method according to claim 1,
And an arc-shaped grass blade having a groove recessed inwardly of the cut-out portion at an edge of the cut portion.
The method according to claim 1,
The blade
Wherein an upper and lower edges of the cut portion extending to one side from the center portion and grooves recessed inward of the cut portion are periodically formed on upper and lower edges of the cut portion extending from the center portion to the other side.
The method according to claim 1,
The blade
An arc-shaped grass blade having an upper edge of the cut portion extending to one side from the central portion and a lower edge of the cut portion extending from the central portion to the other side, the groove being recessed inward of the cut portion periodically.

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