JP2014030421A - Grass-mowing blade, and grass mower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grass-mowing blade capable of suppressing the damage of an installation, and a grass mower.SOLUTION: At the center of a grass-mowing blade 1, there is formed a connecting portion 11 to be connected to a grass mower 3, and the connecting portion 11 is surrounded with a circumferential portion 21 extending from the center of the connecting portion 11. The circumferential portion 21 is so wholly curved that the outer edge is sloped downward. The angle of inclination to a face B normal to a rotation axis A of the grass-mowing blade 1 becomes gradually larger toward the lower side. In the circumferential portion 21, there are formed notches 23 opened in the outer edge. If the distance from the rotation axis A to the outer edge of the circumferential portion 21 of a first end portion 27 is L1, the distance to the outer edge of a second end portion 29 is L2, and the distance to a predetermined position having no notch 23 is L3, L3>L1>L2 is satisfied.

Description

  The present invention relates to a mowing blade used in a mower for cutting weeds and the like.

2. Description of the Related Art As a hand-held mower, one having an operation handle and a driving source such as an engine, and having a cutting blade that is rotationally driven by the driving source at the tip is used.
Conventionally, this grass cutting blade has been generally used as a flat plate as a whole and has a plurality of blades formed on the outer periphery. However, the grass cutting blade is configured such that the tip of the grass cutting blade is inclined upward or downward. A blade has also been proposed (see Patent Documents 1 and 2).

JP-A-5-91814 JP 61-8301 A

  The mowing blade rotates at a very high speed, so if the tip part comes into contact with an object such as concrete, a wall, a pillar embedded in the ground, a net, a fence, or a stone, the object may be damaged. In some cases, the mowing blade may be damaged.

  An object of the present invention is to provide a mowing blade and a mowing machine capable of suppressing breakage of the mowing blade and an installed object.

  The invention according to claim 1, which has been made to solve the above-described problem, is a mowing blade that is used by being attached to a mower, and is connected to a mowing machine, and a connection portion that extends around the connection portion. A peripheral portion whose outer edge is inclined downward, and the peripheral portion is provided with a plurality of cutouts having openings in the outer edge, and a region located at a position further away from the rotary shaft of the cutting blade than the edge portion of the cutout. A first end portion and a second end portion extending from the outer edge of the peripheral portion to the deepest portion having the depth in the center direction of the grass cutting blade among the edges pass through the rotation of the grass cutting blade. In the predetermined range in the vertical direction of the region, there is an interval in the direction orthogonal to the rotation axis of the rotation.

  The grass cutting blade configured as described above can cut grass at the edge of the peripheral portion, particularly at the edge (end surface) of the notch. And since a peripheral part has the area | region far from a rotating shaft rather than this edge part, it becomes difficult for the edge part of a notch to contact an installation thing. On the other hand, the region farther from the rotation axis than the edge portion that easily comes into contact with the installation object is not an end face of the cutout, so that it is difficult to damage the installation object, and it is difficult to degrade the grass cutting performance of the mowing blade.

Therefore, the mowing blade of the present invention can suppress damage to an installed object or the like and damage to the mowing blade.
Moreover, since the space | interval of the direction orthogonal to a rotating shaft is provided between the 1st end part in the edge part of a notch, and a 2nd end part, the grass which should be mowed with a mowing blade easily enters the inside of a notch. As a result, mowing can be performed quickly.

  Further, the cutting blade of the present invention is configured to cut grass at the edge of the notch at the end portion (outer end portion) of the peripheral portion, so that the tip is inclined to the lower side of the peripheral portion. Even if it comes into contact with the ground or the road surface and wears, the function of mowing grass is hardly reduced. On the other hand, when the blade extends horizontally like a conventional mowing blade, the blade will wear out when the tip hits the ground, and the function of cutting grass tends to be reduced, so be careful not to touch the tip to the ground. Must operate.

  That is, the grass cutting blade of the present invention can easily cut grass while operating the grass cutter and moving the grass cutting blade up and down, and as a result, the grass can be cut finely. Further, even grass that lies on the ground like dead grass can be easily mowed by applying a grass cutting blade from above.

In addition, the notch mentioned above means the part of the notch shape provided in the outer edge of the grass cutting blade. Therefore, the formation method of the notch is not particularly limited.
In addition, the peripheral part mentioned above may incline so that a cross section may become curved shape (namely, it may curve), and may incline so that a cross section may become linear form.

  The downward direction of the mowing blade is the downward direction in a state where the mowing blade is attached to the mower. In other words, among the directions along the rotation axis of the mowing blade, the direction with the driving source of the mower and the gripping part used for the operation is the upward direction, and the opposite direction is the direction facing the ground side when used. Direction. This downward direction is defined with reference to the direction in use in order to clarify the explanation of the mowing blade.

  By the way, the predetermined range in the vertical direction described above may be configured to be a range that extends upward from the lower end of the mowing blade. When mowing the grass, the grass often comes into contact with the mowing blade from below, so that the above-described gap between the first end and the second end is provided at the lower end of the mowing blade. Can be mowed.

Moreover, the connection part mentioned above may be comprised so that it may be formed in the surface dented below rather than the circumference | surroundings.
In the grass cutting blade configured in this way, the side of the connecting portion between the connecting portion and the mower main body is covered and hidden by the surrounding portion positioned above the connecting portion. Therefore, it can suppress that grass etc. get entangled in the connection part of a connection part and a mower.

  Further, the region through which the first end passes when the mowing blade rotates is located outside the region through which the second end passes, and is a region sandwiched between two adjacent notches in the peripheral portion. The region having the first end of one notch and the second end of the other notch at the end includes a first region extending from the first end in the rotational direction, and a first region in the first region. A second region protruding in a direction away from the rotation axis from the end opposite to the end, and a third region connected from the protruding tip of the second region to the second end. It may be configured.

  The grass cutting blade configured in this manner generates lift when attached to a mower and rotated. As a result, the mower becomes lighter and easier to operate, so that mowing work can be performed easily. For example, by adjusting the lifting force to make the floating height constant, it is possible to make the traces of grass cutting less noticeable and finish beautifully.

  Moreover, in order to generate lift in the mowing blade, the following configuration may be used. The configuration is that the region through which the first end passes when the mowing blade rotates is located outside the region through which the second end passes, and is sandwiched between two adjacent notches in the peripheral portion. A region having the first end of one notch and the second end of the other notch at the end extends from the first end toward the second end; and A second surface extending from the second end portion toward the first end portion, wherein the first surface is directed from the first end portion side toward the second end portion side. The second surface has a surface whose distance from the rotation axis increases, and the second surface has a surface whose distance from the rotation axis increases from the second end side toward the first end side. This is the configuration.

In addition, the shape of the said 1st surface and the 2nd surface should just be formed in that way as a whole. That is, a part of the first surface or the second surface may protrude for the purpose of improving the strength.
The lift can be adjusted by the shape of the mowing blade, but can also be adjusted by the rotational speed of the mower. Also, the lift can be adjusted by opening a through-hole, for example, around the connecting portion of the mowing blade. When the through hole is opened, the lift is reduced. However, the lift can be adjusted by closing the through hole with a tape or by providing a through hole opening / closing mechanism to close the through hole.

  The invention according to claim 5 is a mowing blade used in a mower, a connecting portion for connecting to the mower, and a peripheral portion extending around the connecting portion and having an outer edge inclined downward. And comprising. The peripheral portion is provided with a plurality of through holes, and has a region located farther from the rotary shaft of the mowing blade than the edge of the through hole, and among the edges of the through hole, The two regions present apart from each other in the direction perpendicular to the vertical direction due to the positional relationship across the through-hole are different in distance from the rotation axis of the rotation.

  In the grass cutting blade configured as described above, since the peripheral portion has a region farther from the rotation axis than the edge portion of the through hole, the edge portion of the through hole is less likely to contact an installation object or the like. On the other hand, the region farther from the rotation axis than the edge portion that easily comes into contact with the installation object is not an end face of the through-hole, so that even if it comes into contact with the installation object, it is difficult to damage or break.

  Therefore, it is possible to suppress damage to the installed object or the like, or damage to the grass cutting blade. Moreover, grass can be cut at the edge of the through hole, and grass cutting can be performed quickly.

In addition, below the through-hole in the said grass cutting blade, the protrusion part extended in an up-down direction and protruded outside may be provided.
The invention according to claim 7 is a mowing blade used in a mower, a connecting portion for connecting to the mower, and a peripheral portion extending around the connecting portion and having an outer edge inclined downward. And comprising. The peripheral portion is provided with a plurality of notches having an opening at the lower end, and has a region located farther from the rotary shaft of the mowing blade than the edge of the notch, and the lower end of the notch at the edge The first end portion and the second end portion that extend from the top to the top end of the region that passes when the mowing blade rotates are spaced in a predetermined range in the vertical direction with respect to the direction orthogonal to the rotation axis of the rotation. It is characterized by.

The grass cutting blade configured as described above can achieve the same operations and effects as the grass cutting blade according to claim 1.
The invention according to claim 9 is a mower having the above-described mowing blade of the present invention. If it is such a mower, the effect that the damage of a mowing blade and an installation thing can be suppressed can be acquired using the mowing blade of this invention mentioned above.

It is a figure which shows the grass cutting blade of Example 1, Comprising: (A) is a perspective view, (B) is a side view, (C) is a top view. It is a side view which shows the state which attached the mowing blade of Example 1 to the mower, Comprising: (A) is a general view, (B) is an enlarged view of the connection part of a mowing blade and a mower. It is typical sectional drawing showing the area | region where a 1st edge part passes, and the area | region where a 2nd edge part passes, when a grass cutting blade rotates, Comprising: (A) is the grass cutting blade of Example 1, (B ) Is a modified mowing blade. It is a figure which shows the grass cutting blade of Example 2, Comprising: (A) is a perspective view, (B) is a side view, (C) is a top view. FIG. 6 is a cross-sectional view taken along the line E-E in FIG. It is a figure which shows the grass cutting blade of a modification, Comprising: (A) is a perspective view, (B) is II sectional drawing of FIG. 6 (A). It is a perspective view which shows the mowing blade of a modification. It is a perspective view which shows the mowing blade of a modification. It is a perspective view which shows the mowing blade of a modification. It is a perspective view which shows the grass cutting blade of Example 3. FIG. FIG. 10 is a perspective view showing a grass cutting blade according to a modification of Example 3. FIG. 10 is a perspective view showing a grass cutting blade according to a modification of Example 3. It is a perspective view which shows the grass cutting blade of Example 4. FIG.

Embodiments of the present invention will be described below with reference to the drawings.
[Example 1]
(1) Configuration of Mowing Blade FIGS. 1A to 1C show the mowing blade 1 of this embodiment. The mowing blade 1 is used in connection with the mower 3 as shown in FIG. This mowing blade 1 is used so as to rotate counterclockwise in FIG. 1 (C), so that the mowing function is exhibited more satisfactorily. Hereinafter, the counterclockwise direction will be described as the rotation direction.

The mowing blade 1 has a substantially circular disk shape as a whole. In the center of the grass cutting blade 1, a connecting portion 11 for connecting with the grass cutter 3 is formed.
The connecting portion 11 includes a central through-hole 13 and a circular plane 15 extending around the center. A peripheral portion 21 that extends around the connecting portion 11 is provided around the connecting portion 11. The connection part 11 is formed in the surface depressed in the downward direction rather than the part around the connection part 11 in the peripheral part 21. A line passing through the center of the through-hole 13 and orthogonal to the plane 15 becomes the rotation axis A when the mowing blade 1 rotates.

  As shown in FIGS. 1A and 1B, the peripheral portion 21 is curved as a whole so that the outer edge is inclined downward. Here, the lower side refers to a downward direction in a state where the mowing machine 3 is attached to the mower 3, and, among the directions along the rotation axis A of the mowing blade 1, the engine 31 that is the driving source of the mowing machine 3 and the operation. This is the direction opposite to the direction in which the gripping part to be used is located. The inclination angle of the grass cutting blade 1 with respect to the plane B orthogonal to the rotation axis A gradually increases as it goes toward the end of the peripheral portion 21. The inclination angle C at the tip of the peripheral portion 21 is formed to be 30 ° to 90 °.

In the following description, the circumferential direction means the circumferential direction around the rotation axis A, and the radial direction means the radial direction of the circle around the rotation axis A.
In the peripheral portion 21, six notches 23 having openings on the outer edge are formed at six equal intervals. The number of the notches 23 is not particularly limited, and may be 7 or more or 5 or less.

  The peripheral portion 21 has the deepest portion 25 having the depth in the center direction of the grass cutting blade 1 at the edge of the notch 23, and the deepest portion 25 from both ends of the opening of the notch 23 at the outer edge of the peripheral portion 21. It has a first end 27 and a second end 29 that follow. The first end portion 27 and the second end portion 29 face each other in opposite directions with respect to the rotation direction of the mowing blade 1.

  As shown in FIG. 1C, the distance from the rotation axis A to the outer edge 27a of the peripheral portion 21 of the first end 27 is L1, the distance from the outer end 29a of the second end 29 is L2, and the notch 23 is provided. When the distance to the predetermined position 21a that is not set is L3, L3> L1> L2. That is, the position 21 a is located farther from the rotation axis A than the edge of the notch 23.

  The ratio between the angle θ1 formed by the position 21a and the outer edge 27a and the angle θ2 formed by the outer edge 27a and the outer edge 29a with respect to the rotation axis A is 1/2> θ1 / θ2> 1/4. It becomes a range. That is, the position 21a is located closer to the outer edge 27a than to the outer edge 29a.

  FIG. 3A is a schematic side cross-sectional view showing a region 27b through which the first end portion 27 passes and a region 29b through which the second end portion 29 passes when the mowing blade 1 rotates. In a predetermined range in the direction (vertical direction) along the rotation axis A of the grass cutting blade 1, the region 27b is spaced in a direction orthogonal to the rotation axis A so that the region 27b is located farther from the rotation axis than the region 29b. ing. The predetermined range is a range that spreads upward from the lower end of the mowing blade 1.

Note that the interval between the region 27b and the region 29b does not change greatly up to the vicinity of the deepest portion 25 (not shown in FIG. 3A) in the vertical direction, and maintains a certain interval or more.
By the way, the grass cutting blade 1 has a waved shape to improve the strength. Specifically, when a portion raised higher than the periphery is a mountain portion, as shown in FIG. 1C, the mountain portion 17 extending in the radial direction is arranged in the circumferential direction in the peripheral portion 21. Is provided.

(2) Attaching the mowing blade to the mower The mower 3 is shown in FIG. 2A and 2B, the mowing blade 1 is shown in a cross-sectional view for easy understanding. The mower 3 includes an engine 31, a pipe shaft 33, a drive shaft 35, a rotation shaft (not shown) disposed inside the pipe shaft 33, and the like. The engine 31 rotates the rotating shaft inside the pipe shaft 33, and the driving shaft 35 is rotated by the rotating force.

  FIG. 2B shows an enlarged view of a connecting portion between the grass cutting blade 1 and the grass cutter 3. The grass cutting blade 1 is fixed by fastening the bolt 39 to the drive shaft 35 by sandwiching the flat surface 15 with a fastener 37 with the tip (lower end) of the drive shaft 35 inserted into the through hole 13 of the connecting portion 11. Thus, it rotates integrally with the drive shaft 35.

  When the engine 31 is driven with the grass cutting blade 1 attached in this way, the rotation shaft and the drive shaft 35 inside the pipe shaft 33 rotate, and the grass cutting blade 1 rotates accordingly, so that weeds and the like can be cut. become able to.

(3) Effect In the grass cutting blade 1 of the present embodiment, the position 21a of the peripheral portion 21 is located outside the edge of the notch 23 with respect to the rotation axis A. That is, when the mowing blade 1 is rotating, the position 21a is likely to first come into contact with an installation such as concrete. Since the position 21 a is located in the middle of the peripheral portion 21, the influence is small as compared with the case where the edge of the notch 23 is in contact with the installation object. Therefore, it can suppress that an installation thing etc. are damaged or the mowing blade 1 is damaged. In addition, injuries when contacting humans and animals can be suppressed.

  Further, the first end 27 at the edge of the notch 23 is located farther from the rotation axis A than the second end 29, and when the grass cutting blade 1 rotates, the second end closer to the rotation axis A side. 29 is ahead of the first end 27 in the rotational direction. Therefore, the grass to be cut enters the notch 23 and is easily cut by the first end portion 27. As a result, the grass can be quickly cut.

  Specifically, the grass that has entered the region D between the region 27 b and the region 29 b shown in FIG. 3A is cut by the first end portion 27. This region D is a region that extends upward from the lower end of the mowing blade 1. Since the grass often comes into contact with the grass cutting blade 1 from below, the grass can be efficiently cut into the region D. Moreover, since the space | interval of the area | region 27b and the area | region 29b is maintained more than fixed width | variety from a lower end to upper direction, grass can be cut well in the wide range in the side of the grass cutting blade 1. FIG.

  Further, in the case of the grass cutting blade 1 of the present embodiment, as shown in FIG. 2B, the grass cut by the peripheral portion 21 or the grass 7 that has been rowed is in contact with the inclined surface of the rotating grass cutting blade 1. At this time, it is flipped out in the direction of the outside of the mowing blade 1 (outside in the radial direction). Therefore, as a result of the grass becoming difficult to get on the grass cutting blade 1, the grass can be prevented from being entangled and the grass cutter 3 can be prevented from getting caught.

  Furthermore, since the connection part 11 is formed in the surface depressed in the downward direction rather than the part around the connection part 11 in the peripheral part 21, the side of the connection part of the connection part 11 and the mower 3 main body is the connection part. 11 is hidden by the surrounding portion positioned above 11. Therefore, it can suppress that the grass etc. which were cut or before cutting are entangled with the connection part of the connection part 11 and the mower 3.

  By the way, as mentioned above, since the inclination angle C at the front-end | tip of the peripheral part 21 shown to FIG. 1 (B) inclines below by 30 degrees-90 degrees, the damage of the mowing blade 1 and an installation thing can be suppressed. However, if the inclination angle is too large, the mowing efficiency becomes low. Also, the greater the angle of inclination, the greater the damage suppression effect. Therefore, by setting the inclination angle C of the tip of the peripheral portion 21 in the range of 30 ° to 80 °, the mowing efficiency can be improved while achieving the suppression of damage to the grass cutting blade 1 and the installation and the suppression of grass entanglement. Can be kept high. Further, when emphasizing the efficiency of mowing, the angle may be 30 ° to 60 °, and when emphasizing the damage suppression effect, the angle may be 45 ° to 80 °.

In addition, although the suppression effect of the damage of the grass cutting blade 1 or an installation thing falls a little, the inclination-angle C may be 30 degrees or less.
In addition, when the diameter of the grass cutting blade 1 is 20 to 30 cm and the width of the notch 23 is 4 to 8 cm, the difference between L1 and L2 may be about 8 to 20 mm, but is appropriately adjusted according to the object to be cut. It is good to use it.

[Example 2]
(1) Configuration of Mowing Blade FIG. 4 shows the mowing blade 51 of this embodiment. The mowing blade 51 is used by being attached to the mower 3 shown in FIG.

  The mowing blade 51 has a substantially disk shape as a whole, and a connecting portion 53 for connecting to the mower 3 is formed at the center of the mowing blade 51. The connecting portion 53 includes a central through hole 55 and a circular flat surface 57 extending around the periphery. The mowing blade 51 is used so as to rotate counterclockwise in FIG.

  A peripheral portion 61 that extends around the connecting portion 53 is provided around the connecting portion 53. As shown in FIGS. 4A and 4B, the peripheral portion 61 is curved as a whole so that the outer edge is inclined downward. The peripheral portion 61 is composed of a circular upper portion 63 inclined relatively downward in a portion adjacent to the connecting portion 53 and a lower portion 65 inclined downward at a relatively steep angle around the upper portion 63.

  At the boundary portion between the upper portion 63 and the lower portion 65, a ridge 63a is formed so as to surround the outer periphery of the upper portion 63. The ridge 63 a protrudes upward from the boundary portion between the upper portion 63 and the lower portion 65. The grass cutting blade 51 is restrained from changing its shape by the ridges 63a, and in particular, prevents the lower portion 65 from opening upward.

In addition, in the boundary part of the upper part 63 and the lower part 65, it may replace with the said protruding item | line 63a and the recessed item | dent recessed downward may be formed, and there exists said effect also in that case.
In the lower part 65, notches 67 having openings at outer edges are formed at six locations at equal intervals. The peripheral part 61 continues from the edge part of the notch 67 to the deepest part 69 having the depth in the center direction of the grass cutting blade 51 and the deepest part 69 from both ends of the opening of the notch 67 on the outer edge of the peripheral part 61. It has a first end 71 and a second end 73. As shown in FIG. 4C, if the distance from the rotation axis A to the outer edge of the peripheral portion 61 of the first end 71 is L1, and the distance from the outer edge of the second end 73 is L2, then L1> L2. Become.

  The shape of the portion other than the notch 67 in the lower portion 65 of the peripheral portion 61 will be described in order from the front in the rotation direction. 4C is an EE cross section of FIG. 4B of one blade piece 91 located between two notches 67. FIG. The blade piece 91 is the entire portion located between the two cutouts 67 and is a portion extending obliquely downward from the upper portion 63. In this blade piece 91, the first end 71 of one notch 67 and the second end 73 of the other notch 67 of the two notches 67 sandwiching the blade piece 91 are circumferential ends. The shape of the portion F (the cross section of the blade piece 91) is a similar shape with no significant change in the cross section of any portion from the lower end of the peripheral portion 61 to the vicinity of the height of the deepest portion 69 of the notch 67. .

  In the blade piece 91, in a predetermined range in the circumferential direction from the first end 71, a front portion 81 whose distance from the rotation axis A is constant in the circumferential direction is provided. A protrusion 83 protruding in a direction away from the rotation axis A is provided at the rear of the front portion 81 in the rotation direction, that is, at the end opposite to the first end portion 71. The vicinity of the apex (protruding tip) in the radial direction of the protruding portion 83 is a point farthest from the rotation axis A in the peripheral portion 61. The connecting portion between the front portion 81 and the protruding portion 83 is a curved surface having a relatively small radius, and after the protruding portion 83 rises in the radial direction, it is rounded and gradually becomes an angle along the circumferential direction. That is, the projecting portion 83 is a surface whose distance from the rotation axis A increases as it goes from the first end portion 71 side to the second end portion 73 side.

  A rear portion 85 that is smoothly continuous without unevenness is provided behind the protruding portion 83. The rear portion 85 gradually approaches the rotation axis A, and the rear end of the rear portion 85 is connected to the second end portion 73 of the notch 67. In FIG. 4C, if the distance from the rotation axis A to the front portion 81 is L3, the distance to the apex of the protrusion 83 is L4, and the distance to the rear portion 85 is L5, then L4> L3, L4> L5. L5> L3 at the front in the rotation direction (projection 83 side), but L3> L5 in the vicinity of the second end 73. The rear portion 85 is a surface whose distance from the rotation axis A increases as it goes from the second end portion 73 side to the first end portion 71 side.

  The front portion 81 is an example of the first region in the present invention, the protruding portion 83 is an example of the second region in the present invention, and the rear portion 85 is an example of the third region in the present invention. Furthermore, the front part 81 and the protrusion part 83 are an example of the 1st surface in this invention, and the back part 85 is an example of the 2nd surface in this invention.

(3) Effect The mowing blade 51 of the present embodiment can obtain the same effects as the mowing blade 1 of the first embodiment, and can obtain lift by rotation. The mechanism is explained.

  FIG. 5 is an EE cross section of FIG. Among the arrows shown in FIG. 4C and FIG. 5, the solid arrow H <b> 1 indicates the flow of air passing outside the peripheral portion 61 when the mowing blade 51 rotates, and the broken arrow H <b> 2 passes inside the peripheral portion 61. Shows air flow.

  The blade piece 91 can obtain lift like a wing of an airplane when rotating. Since the outside of the peripheral portion 61 bulges outward due to the protruding portion 83, the flow velocity of air becomes larger than that on the inside. Moreover, it will be in the state in which the rear part 85 forms the angle of attack. Thereby, a lift is generated in a direction (arrow G direction) intersecting the main surface of the blade piece 91, and an upward lift can be obtained as the entire mowing blade 51.

  Moreover, since the air which passes the outer side of the back part 85 flows smoothly to the outer side and the inner side of the back blade piece 91 by the smooth back part 85, as shown in FIG. 5, lift can be obtained efficiently.

  As a result of the generation of lift as described above, the entire mower 3 can be handled lightly, so that the height of the mowing blade can be easily adjusted during mowing, and the finish can be easily adjusted by adjusting the height of the grass. Can be. For example, by adjusting the lifting force to make the floating height constant, it is possible to make the traces of grass cutting less noticeable and finish beautifully.

In addition, lightening makes it difficult for operational errors to occur, improving safety and reducing the burden on workers.
Moreover, since the grass cutting blade 51 is less likely to contact the ground, scattering due to the contact of pebbles and sand can be suppressed. Further, since wind is generated when the mowing blade 51 is rotated, the wind can be used as a cleaning blower.

  In the mowing blade 51, the front part 81, the protruding part 83, and the rear part 85 can be formed in various shapes as long as lift can be obtained. For example, the front part 81 may be inclined with respect to the circumferential direction. When the diameter of the grass cutting blade 51 is 20 to 30 cm, the circumferential width of the front portion 81 is set to about 5 to 10 mm at the lower end portion, and the apex of the front portion 81 and the protruding portion 83 from the rotation axis A. When the distance difference (L4-L3) is about 2 to 10 mm, lift is easily generated.

[Modification of Embodiments 1 and 2]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various forms can be taken as long as they belong to the technical scope of the present invention.

  For example, the material of the grass cutting blade in each of the above embodiments is not particularly limited, but when the grass cutting blade comes into contact with the installation object, it strongly receives the force of bending downward, so by using high-tensile steel (high tensile material), Damage can be reduced.

Moreover, in each said Example, although the structure which the inclined surface of the outer edge curved is illustrated, you may incline so that a cross section may become linear form.
Further, in each of the above-described embodiments, the configuration in which the region other than the connecting portions 11 and 53 is curved as a whole is illustrated. However, for example, a part of the portion adjacent to the connecting portions 11 and 53 is orthogonal to the rotation axis A. It may be formed as a flat surface.

  Moreover, although the connection parts 11 and 53 illustrated the structure formed in the surface depressed in the downward direction rather than the circumference | surroundings, you may form in the same height as the circumference | surroundings, or a surface higher than the circumference | surroundings. Moreover, although the connection parts 11 and 53 illustrated the structure which consists of the through-holes 13 and 55 and the planes 15 and 57, if the lawn mower 3 can be connected, the specific shape will not be specifically limited.

  Moreover, as shown in FIGS. 6 (A) and 6 (B), the grass cutting blade 51 described in the second embodiment may be provided with a circumferential protrusion 101 on the blade piece 91. The grass cutting blade configured as described above can increase the strength of the blade piece 91 and suppress the deformation of the blade piece 91. The number of ridges 101 is not limited to two as illustrated, but may be one or three or more. Moreover, you may provide a concave line in place of a convex line.

  Further, a through hole 103 may be formed in the upper part 63 in order to adjust the lift. The number and size of the through holes 103 are not particularly limited, but the lift increases as the number increases. Therefore, it is possible to adjust the lift so that the lift does not decrease too much by attaching a tape so as to close the through hole or by providing an opening / closing mechanism for the through hole to reduce the opening of the through hole.

  Furthermore, like the mowing blade 51a shown in FIG. 7, the upper portion 61 may be provided with a ridge 87 inclined with respect to the circumferential direction. The ridge 87 is closer to the rotation axis A toward the front in the rotation direction, and the grass is blown outward when the grass cutting blade 51a is rotated, so that the grass is entangled with the connection portion between the connection portion 53 and the grass cutter 3. This can be suppressed to a higher degree.

  4 and 6 has a configuration in which the connecting portion between the front portion 81 and the protruding portion 83 is connected by a curved surface having a relatively small radius, and the connecting portion has a relatively large angle. On the other hand, the mowing blade 51a of FIG. 7 is formed so that the angle of the connecting portion between the front portion 81a and the protruding portion 83a is small, and the entire blade piece 91a is a smooth flat surface except for the protruding portion. Even with the grass cutting blade 51 a configured as described above, lift can be obtained in the same manner as the grass cutting blade 51.

  Moreover, you may comprise the grass cutting blade of this invention like the grass cutting blade 111 shown in FIG. The mowing blade 111 has a connecting portion 113 and a peripheral portion 115 whose outer edge is inclined downward, and is provided with a plurality of notches 117 having openings on the outer edge. The outer edge of the peripheral portion 115 has a region located at a position farther from the rotation axis A of the mowing blade 111 than the edge portion of the notch 117.

  In the vicinity of the deepest part 119 of the notch 117, a convex part 131 protruding outward is formed, and a convex part 133 is also formed in an intermediate part between the convex parts 131. The strength of the grass cutting blade 111 is increased by the convex portion 131 and the convex portion 133, and the peripheral portion 115 is prevented from being deformed so as to bend upward.

Regarding the first end 121 and the second end 123 that continue to the deepest part 119, the region through which the first end 121 passes during rotation is located outside the region through which the second end 123 passes.
The vicinity of the outer edge of the peripheral portion 115 is bent inward by a bent portion 135. The bent portion 135 is closer to the outer edge of the peripheral portion 115 on the first end portion 121 side, but is closer to the center side of the mowing blade 111 toward the second end portion 123 side.

  FIG. 3B is a schematic side sectional view showing a region 121a through which the first end 121 passes and a region 123a through which the second end 123 passes when the grass cutting blade 111 rotates. In a predetermined range in the direction (vertical direction) along the rotation axis A of the grass cutting blade 111, the region 121a has a distance in a direction orthogonal to the rotation axis A so that the region 121a is located farther from the rotation axis than the region 123a. ing. In the grass cutting blade 111, the region D between the 121a and the region 123a is wider toward the lower end and narrower toward the upper end.

  Moreover, you may comprise so that the ring part 149 may be provided like the mowing blade 141 shown to FIG. 9 (A)-(C). The mowing blade 141 has a connecting portion 143 and a peripheral portion 145 whose outer edge is inclined downward, and is provided with a plurality of notches 147 having openings at the outer edge. The outer edge of the peripheral portion 145 has a region located farther from the rotation axis A of the grass cutting blade 111 than the edge of the notch 147.

  The peripheral portion 145 is provided with a semi-annular (semi-cylindrical) ring portion 149 protruding in a direction away from the rotation axis A. The ring portion 149 has a through hole 149a, and the through hole 149a is arranged so that the through direction of the through hole 149a is along the circumferential direction (rotational direction) of the mowing blade 141.

  The grass cutting blade 141 configured as described above can cut grass or the like not only at the outer edge portion of the notch 147 and the peripheral portion 145 but also at the end portion of the ring portion 149, thereby improving the efficiency of the mowing operation.

  In addition, the shape of the ring part 149 is not limited to what is shown to FIG. 9 (A)-(C), It can be set as the various shapes which are substantially cyclic | annular. For example, the shape which a part of cyclic | annular form has cut | disconnected may be sufficient. The general shape of the cross section of the annular portion may be a shape other than a circle, and may be, for example, an ellipse or a substantially rectangular shape. The grass cutting blade 141 can give the cutting blade 141 a sharpness different from the outer edges of the notch 147 and the peripheral portion 145 according to the shape of the ring portion 149.

The modifications described in this section may be applied to the configurations of the following third and fourth embodiments.
[Example 3]
(1) Configuration of Mowing Blade In the first and second embodiments, the mowing blade having a notch having an opening at the outer edge is illustrated, but in this embodiment, the mowing blade that forms a through hole instead of the notch is described. To do. FIG. 10 shows a mowing blade having a through hole.

  The mowing blade 151 has a substantially disc shape as a whole, and a connecting portion 153 for connecting to the mower 3 is formed at the center of the mowing blade 151. The shape of the connecting portion 153 is the same as that of the connecting portion 11 in the grass cutting blade 1 of the first embodiment.

  A peripheral portion 161 that extends around the connecting portion 153 is provided around the connecting portion 153. The peripheral portion 161 is curved as a whole so that the outer edge is inclined downward. The peripheral portion 161 has six through holes 163 formed at equal intervals. In addition, the peripheral portion 161 has a region 161 a that is located farther from the rotation axis A of the mowing blade 151 than the edge portion of the through hole 163.

  This mowing blade 151 is used to turn counterclockwise. Of the edge of the through hole 163, the front region 165 positioned in the rotation direction is closer to the rotation axis A than the rear region 167 positioned on the opposite side of the rotation direction of the edge of the through hole 163. Is provided. That is, the distance from the rotation axis A is different between the front region 165 and the rear region 167 that exist apart in the horizontal direction perpendicular to the vertical direction due to the positional relationship across the through-hole 163.

Further, below the through hole 163 in the grass cutting blade 151, two protruding portions 171 extending in the vertical direction and protruding outward are formed.
(2) Effect In the grass cutting blade 151 configured as described above, the region 161 a is located outside the edge of the through hole 163 with respect to the rotation axis A. That is, the region 161a is easy to contact with an installation such as concrete at first, but since the region 161a is formed in a curved surface, the influence is small as compared with the case where the edge of the through hole 163 contacts the installation. Further, it is possible to suppress damage to the installation object and the grass cutting blade 151. Injuries when contacting people or animals can also be suppressed.

  The front area 165 is closer to the rotation axis A than the rear area 167. That is, the positional relationship is the same as that of the second end portion 29 and the first end portion 27 in the grass cutting blade 1 of the first embodiment. Therefore, the edge of the through hole 163 acts in the same manner as the edge of the cutout of the grass cutting blade 1, and when the grass cutting blade 151 rotates, the grass to be cut enters the inside of the through hole 163 and the grass by the edge of the rear region 167. Can be cut easily, and as a result, mowing can be performed quickly.

  In the present embodiment, the front region 165 is generally provided at a position closer to the rotation axis A than the rear region 167, but the front region 165 rotates more than the rear region 167 at least in a predetermined range in the vertical direction. What is necessary is just to be provided in the position close | similar to the axis | shaft A. FIG.

  Further, the grass cutting blade 151 is similar to the grass cutting blade 1 of the first embodiment, because the grass cut off is repelled outward by the inclined surface, so that the grass becomes difficult to ride on, resulting in the grass becoming entangled and the grass cutter 3 removing the grass. Entrainment can be suppressed.

  Further, unlike the first and second embodiments, the grass cutting blade 151 has a through hole instead of a notch. Therefore, since the outer edge of the mowing blade 151 has a continuous shape without interruption, it is possible to suppress the outer edge of the mowing blade 151 from being deformed or damaged due to the mowing blade 151 coming into contact with an installation object or the like.

Moreover, since the downward part of the through-hole 163 is wavy by the protrusion part 171, the sharpness in the part can be improved.
By the way, the grass cutting blade 151 of the present embodiment is not formed with a notch. The cutout is particularly effective when cutting relatively hard shrubs, bamboo, and the like, but when cutting relatively soft weeds, the cutout performance is sufficiently exhibited even in portions where the cutout is not formed. For this reason, the outer edge of the grass cutting blade 151 has a continuous shape, so that when cutting relatively soft things such as weeds, the grass cutting blade 151 can be cut quickly and at least as fast as the grass cutting blades described in the first and second embodiments. It can be performed.

On the other hand, since the notches are formed in the grass cutting blades of the first and second embodiments, cutting can be performed quickly even if they are relatively hard.
(3) Other Shapes The peripheral portion 161 may be formed to have a cross-sectional shape as shown in FIG. 5 like the grass cutting blade 51 of the second embodiment. By forming in this way, it becomes possible to obtain lift by rotation as with the grass cutting blade 51 of the second embodiment. Note that the space between the blade pieces 91 shown in FIG.

  Further, the shape below the through-hole 163 is not limited to the shape shown in FIG. For example, only one protrusion 171 may be formed like a grass cutting blade 151a shown in FIG. 11A, or three or more may be formed.

Further, unlike the grass cutting blade 151b shown in FIG. 11B, the protruding portion 171 may not be provided, and a gently continuous shape may be employed.
Moreover, the structure which provides the cover part 173 which closes the upper end of the part which the protrusion part 171 protruded like the mowing blade 151c shown in FIG.11 (C) may be sufficient. By providing the lid portion 173, the strength of the lower portion of the through hole 163 can be improved.

Moreover, you may comprise like the mowing blade 191 shown in FIG. 12 as a mowing blade which has a through-hole.
The mowing blade 191 has a substantially disk shape as a whole, and a connecting portion 193 for connecting to the mower 3 is formed at the center of the mowing blade 191. The shape of the connection part 193 is the same as that of the connection part 11 in the mowing blade 1 of Example 1 except that the hole 193a is partly provided.

A peripheral portion 201 that extends around the connecting portion 193 is provided around the connecting portion 193. The peripheral portion 201 is curved as a whole so that the outer edge is inclined downward.
The peripheral portion 201 is formed with a plurality of recesses 203 (six in this embodiment) that are recessed from the periphery, and an air hole 205 is formed behind the mowing blade 191 in the recess 203. A smooth curved surface is formed from the peripheral part 201 to the air hole 205 via the recessed part 203. When the cutting blade 191 rotates, air flows into the inside (lower side) of the cutting blade 191 through the air hole 205.

  On the outer edge side of the peripheral portion 201 with respect to the concave portion 203, a plurality of convex portions 207 swelled from the periphery are formed (six in this embodiment, the number is not particularly limited). The convex portion 207 has a length along the rotational direction, and a through-hole 209 is formed in front of the rotational direction.

  Among the edge portions of the through hole 209, the first region 210 and the second region 211 that are separated in the horizontal direction with respect to the position of the through hole 209 are spaced with respect to the direction orthogonal to the rotation axis A. . The first region 210 is provided at a position closer to the rotation axis A than the second region 211, and the through hole 209 is open facing forward in the rotational direction when viewed from the outside of the mowing blade 191.

The peripheral portion 201 has a region 201 a that is located farther from the rotation axis A of the mowing blade 191 than the edge portion of the through hole 209.
The grass cutting blade 191 configured in this way can also achieve the same effects as the grass cutting blade 151. That is, it is possible to suppress breakage of the installed object and the grass cutting blade and to prevent injury when it comes into contact with a person, and it is possible to quickly cut grass by cutting the grass with the edge of the through hole 209. Moreover, it can suppress that the mower 3 entraps grass.

[Example 4]
FIGS. 13A to 13C show the mowing blade 221 of this embodiment. The mowing blade 221 is used in connection with the mowing machine 3 shown in FIG. This mowing blade 221 is used so as to rotate counterclockwise in FIG. 13 (C), so that the mowing function is more satisfactorily exhibited.

  The mowing blade 221 has a substantially circular disk shape as a whole. A connecting portion 223 for connecting to the mower 3 is formed at the center of the mowing blade 221. The shape of the connection part 223 is the same as that of the connection part 11 in the mowing blade 1 of Example 1 except that the hole 223a is partly provided.

  A peripheral portion 231 that extends around the connecting portion 223 is provided around the connecting portion 223. As shown in FIGS. 13A and 13B, the peripheral portion 231 is curved as a whole so that the outer edge is inclined downward. Here, the lower side refers to a downward direction in a state where the mowing machine 3 is attached to the mower 3, and the direction along the rotation axis A of the mowing blade 221 is the engine 31 that is the driving source of the mowing machine 3 and the operation. This is the direction opposite to the direction in which the gripping part to be used is located.

  A plurality of recesses 233 (six in this embodiment) that are recessed from the periphery are formed in the peripheral portion 231, and air holes 235 are formed in the recess 233 at the rear in the rotation direction of the mowing blade 221. A smooth curved surface is formed from the peripheral portion 231 to the air hole 235 via the concave portion 233. When the grass cutting blade 221 rotates, air flows into the grass cutting blade 221 through the air hole 235 (lower side).

  The outer edge of the peripheral portion 231 is formed with a plurality of dome portions 237 that are rounded upward (in the present embodiment, six locations, the number of which is not particularly limited). The dome portion 237 as a whole has a large bulge in the front in the rotational direction and a small bulge in the rear in the rotational direction. The lower end on the outer edge side is gently curved inward (rotation axis A side), and in particular, the front in the rotational direction is shaped to be wound under the mowing blade 221. A cutout 239 having an opening at the lower end is formed at the front end of the dome 237 in the rotational direction.

  The edge of the notch 239 has a first end 243 and a second end 245 located on both sides of the notch 239, and an upper edge 241 located at the upper end of the notch 239, and the first end 243 and A second end 245 continues from the lower end of the notch 239 to the upper edge 241.

  The first end 243 is formed at a position farther from the rotation axis A than the second end 245. For this reason, in a region in which the first end 243 and the second end 245 pass when the mowing blade 221 rotates, there is an interval in a direction perpendicular to the rotation axis A in a predetermined range in the vertical direction. In the present embodiment, the predetermined range is substantially the entire region from the lower end to the upper edge 241. However, it is sufficient that there is an interval in at least a partial range in the vertical direction.

The notch 239 opens from the outside of the mowing blade 221 so as to face forward in the rotational direction.
In addition, the peripheral portion 231 has a region 231 a that is located farther from the rotation axis A of the mowing blade 221 than the edge portion of the notch 239.

  The grass cutting blade 221 configured in this way can also achieve the same effects as the grass cutting blade 1 of the first embodiment. That is, it is possible to suppress damage to the installation object and the grass cutting blade 221 and to prevent injury when it comes into contact with a person. Further, by cutting the grass with the edge of the notch 239, the grass cutting can be performed quickly. Moreover, it can suppress that the mower 3 entraps grass.

  In addition, the grass cutting blade 221 has a rounded dome portion 237 located on the outer edge, and the lower end of the dome portion 237 also curves inward, so that the danger when it comes into contact with an installation or a person can be reduced to a higher degree. It can also prevent the wrapping of grass.

DESCRIPTION OF SYMBOLS 1 ... Mowing blade, 3 ... Mowing machine, 7 ... Grass, 11 ... Connection part, 13 ... Through-hole, 15 ... Plane, 17 ... Mountain part, 21 ... Peripheral part, 21a ... Position, 23 ... Notch, 25 ... Deepest part 27 ... first end, 27a ... outer edge, 27b ... region, 29 ... second end, 29a ... outer edge, 29b ... region, 31 ... engine, 33 ... pipe shaft, 35 ... drive shaft, 37 ... fastener, 39 ... Bolt, 51, 51a ... Mowing blade, 53 ... Connecting part, 55 ... Through hole, 57 ... Flat surface, 61 ... Peripheral part, 63 ... Upper part, 63a ... Projection, 65 ... Lower part, 67 ... Notch, 69 ... Deepest 71, first end portion, 73, second end portion, 81, 81a, front portion, 83, 83a, projecting portion, 85, rear portion, 87, convex strip, 91, 91a, blade piece, 101, convex 103, through hole, 111, mowing blade, 113, connecting portion, 115, peripheral portion, 117, notch, 11 ... deepest part, 121 ... first end part, 121a ... area, 123 ... second end part, 123a ... area, 131 ... convex part, 133 ... convex part, 135 ... bent part, 141 ... mowing blade, 143 ... connecting part 145 ... peripheral portion, 147 ... notch, 149 ... ring portion, 149a ... through hole, 151 ... mowing blade, 151a-c ... mowing blade, 153 ... connecting portion, 161 ... peripheral portion, 161a ... region, 163 ... through hole 165 ... Front region, 167 ... Rear region, 171 ... Projection, 173 ... Lid, 191 ... Mowing blade, 193 ... Connection part, 193a ... Hole, 201 ... Peripheral part, 201a ... Region, 203 ... Recess, 205 ... Air hole, 207 ... convex portion, 209 ... through hole, 210 ... first region, 211 ... second region, 221 ... mowing blade, 223 ... connecting portion, 223a ... hole, 231 ... peripheral portion, 231a ... region, 233 ... Recess 235 Air hole, 237 ... dome, 239 ... notch, 241 ... upper edge, 243 ... first end, 245: second end

Claims (9)

A mowing blade used in a mower,
A connecting portion for connecting to the mower;
A peripheral portion that extends around the connecting portion and whose outer edge is inclined downward,
The peripheral portion is provided with a plurality of cutouts having an opening at the outer edge, and has a region located farther from the rotary shaft of the grass cutting blade than the edge portion of the cutout,
Of the edge portion, the first end portion and the second end portion that continue from the outer edge of the peripheral portion to the deepest portion having the depth in the center direction of the grass cutting blade pass through when the grass cutting blade rotates. In a predetermined range in the vertical direction, there is an interval in a direction orthogonal to the rotation axis of the rotation. The said predetermined range is a range which spreads upwards from the lower end of the said mowing blade. The mowing blade of Claim 1 characterized by the above-mentioned. The region through which the first end passes during rotation is located outside the region through which the second end passes during rotation,
A region sandwiched between two adjacent notches in the peripheral portion, the region having the first end of one notch and the second end of the other notch at the end,
A first region extending in the rotational direction from the first end;
A second region projecting in a direction away from the rotation axis from an end opposite to the first end in the first region;
The grass cutting blade according to claim 1, further comprising: a third region connected to the second end portion from a protruding tip of the second region. The region through which the first end passes during rotation is located outside the region through which the second end passes during rotation,
An area sandwiched between two adjacent notches in the peripheral portion and having the first end portion of one of the notches and the second end portion of the other notch at the end portions, A first surface extending from one end portion toward the second end portion, and a second surface extending from the second end portion toward the first end portion;
The first surface has a surface whose distance from the rotation axis increases as it goes from the first end side to the second end side,
The said 2nd surface has a surface where the distance from the said rotating shaft becomes far as it goes to the said 1st end part side from the said 2nd edge part side. The mowing blade according to 2. A mowing blade used in a mower,
A connecting portion for connecting to the mower;
A peripheral portion that extends around the connecting portion and whose outer edge is inclined downward,
The peripheral portion is provided with a plurality of through-holes, and has a region located farther from the rotary shaft of the mowing blade than the edge of the through-hole,
Of the edges of the through hole, two regions that are separated in a direction perpendicular to the vertical direction due to the positional relationship across the through hole have different distances from the rotation axis of the rotation. Mowing blade.   The mowing blade according to claim 5, wherein a protruding portion that extends in the vertical direction and protrudes outward is provided below the through hole in the mowing blade. A mowing blade used in a mower,
A connecting portion for connecting to the mower;
A peripheral portion that extends around the connecting portion and whose outer edge is inclined downward,
The peripheral portion is provided with a plurality of cutouts having an opening at the lower end, and has a region located at a position farther from the rotation axis of the grass cutting blade than the edge portion of the cutout,
Of the region where the first end and the second end extending from the lower end to the upper end of the notch at the edge pass through when the mowing blade rotates, in a predetermined range in the vertical direction, the rotation axis of the rotation A mowing blade characterized by having an interval in an orthogonal direction. The mowing blade according to any one of claims 1 to 7, wherein the connecting portion is formed on a surface that is recessed downward from the periphery of the connecting portion.   A mower having the mowing blade according to any one of claims 1 to 8.