JP2584133B2 - Grass and lawn mowing cutter blade - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grass blade for cutting grass and lawn which rotates substantially horizontally, and more particularly, to a cutting blade provided from an end portion thereof to an intermediate portion near a center of rotation, and has a rear end in a rotation direction. The present invention relates to a structure of an upward blast piece provided in the section and a push-down piece provided in an intermediate portion closer to the center of rotation than the upward blast piece to direct the wind downward.

[0002]

2. Description of the Related Art A lawn mower having a substantially horizontally rotating cutter blade provided with a cutting blade at an end thereof and a wind-up piece provided upwardly behind the cutting blade in the rotation direction is disclosed in U.S. Pat. No. 4,158,279. Also, a cutting blade is provided from the end of the cutter blade to an intermediate portion near the center of rotation, and the wind is directed to an intermediate portion closer to the center of rotation than the upward wind piece provided at the end on the rear side in the rotation direction. U.S. Pat. No. 4,189,903 discloses a downwardly extending depressing piece parallel to the cutting blade.

[0003]

By the way, in order to cut the cut grass, it is conceivable to incline the blast pieces above the ends toward the center of rotation. However,
In this case, in the case where a pressing piece parallel to the cutting blade is provided at the intermediate portion as disclosed in the above-mentioned U.S. Pat. No. 4,189,903, the airflow is generated by an upward wind piece inclined toward the center of rotation. Due to the wind action, the flow of the cut turf, which rises once and then falls onto the cutting blade in the middle of the blade, is generated by centrifugal force. At this time, there is a possibility that the flow of the wind is disturbed, so that the shred of the cut turf cannot be obtained well and that the dispersibility on the turf cannot be obtained.

Accordingly, an object of the present invention is to provide a cutting blade provided from an end portion to an intermediate portion near the center of rotation, by means of a blast piece rising upward from a rear end portion in the rotation direction, thereby using a cutting blade at the end portion. The cut grass and lawn is raised once, dropped on the cutting blade in the middle part, and the depressed piece in the middle part promotes a good flow of wind to the cutting blade part in the middle part. It is an object of the present invention to provide a grass and lawn mowing cutter blade capable of improving cutting performance and uniformly dispersing toward a rotation center.

[0005]

The present invention to solve the above problems, there is provided a means for solving] it includes a cutting blade 22 provided from the end portion of the rotating blades substantially horizontal to the intermediate portion of the rotation center portion closer, the cutting blade 2
It provided so as to stand on the edge portion of the rotation direction rear side with respect to 2
And causing Kazehen 23, Te electromotive Kazehen 23 the rotation center side of the depressed piece 25 and the cutter blade 21 odors for grass mowing with a directing wind provided as hanging in the intermediate part lower than this , The blast piece 23, the cutter blade
21 to a line L2 parallel to the center line L1 passing through the rotation center axis.
On the other hand, the line L3 inclined by the angle θ is trough-folded as a valley and
To be provided with an inclined surface,
Is provided adjacent to the edge on the side having the blast pieces 23,
Further, the press-down piece 25 is
For a line L2 parallel to the center line L1 passing through the rotation center axis,
The line L4 inclined by the angle α is trough-folded as a valley and falls downward
To provide a wind-facing slope at the center of rotation.
And wherein the digit.

Further, according to the present invention, the cutting blade 22 is gradually inclined so as to recede in a direction opposite to the rotation direction toward the tip, and a stepped portion is provided between the intermediate portion and the rotation center portion. It is also characterized by being provided.

[0007]

[Function] The cut grass blades cut by the cutting blade at the end are once raised upward by the blast pieces upward at the end inclined toward the center of rotation, and then fall onto the cutting blade at the intermediate portion. And, due to the inclined surface of the push-down piece in the middle part directed toward the center of rotation, the wind actively flows to the cutting blade part in the middle part, so that the shredding property is enhanced and it is evenly distributed toward the center of rotation. Is done. That is, the ground turf can be dropped more uniformly below the turf than before.

[0008] Further, by gradually inclining the cutting blade portion so as to recede in the direction opposite to the rotation direction toward the front end, the cutting ability for grass and grass is improved. Further, by providing a step between the intermediate portion and the rotation center portion, the impact applied to the end portion is reduced at the step.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a lawn mower as an example to which the present invention is applied.
2, reference numeral 1 denotes an airframe, 2 denotes a front wheel, 3 denotes a rear wheel, 4
Is a handle, 5 is a seat, 6 is an engine, 10 is a cutter housing, and 21 is a cutter blade. As shown in the drawing, a cutter housing 10 is disposed below a substantially central portion of the machine body 1 via a pair of front and rear links 7 and 8, and a vertical axis 20 at the center of a cutter blade 21 housed in the cutter housing 10 is supplied from the engine 6. Is transmitted via the belt pulley device 9 and the like. Thereby, the cutter blade 21 performs substantially horizontal rotation.

As shown in FIGS. 3 and 4, a substantially circular cutter housing 10 having an open lower surface has a scroll portion 12 bulging upward except for a rear portion of an upper wall portion 11 thereof.
And a discharge port 17 that opens laterally through a discharge duct 16 on one side of the peripheral wall 15. Three air intakes 13 are formed in the center of the upper wall 11.

Here, the scroll portion 12 is formed so as to be gradually higher (see FIG. 4) in order to increase the air flow toward one side discharge duct portion 16 along the rotation direction R of the cutter blade 21 (see FIG. 3). The discharge duct portion 16 is formed in the scroll portion 12 continuously in the tangential direction at a point P on the outer peripheral side as shown in FIG. In addition, as shown in FIG.
9 can be connected.

[0012] mosquito Tsu coater blade 21, as shown in FIG. 9 and 10
To Ru street der showing an enlarged also. Figure 9 shows the cutter blade
21 is a perspective view of a half portion including one of the cutting blades of FIG.
FIG. 10 is a plan view of the same. Cutter shake
The mode 21 has a rectangular plate shape with one side extremely longer than the other side.
In the shape of a strip. The cutter blade 21 is in the length direction
The shaft 20 which forms the drive shaft at the center in the width direction at the center of
Mounting hole 21 to be attached to blade via blade holder 29
a, and rotates about the mounting hole 10a.

The above-mentioned cutter blade 21 is arranged in the longitudinal direction.
Central portion 10A, and a central portion 10A
The middle part 10B which continues, the outside of the length direction of the middle part 10B
Is provided on both sides in the longitudinal direction, and a middle portion is provided.
10B is a central part 10A and a tip part 10C which are continuous with this.
The bulging portion 24 bulges one step further upward. Figure
At 10, the direction of the arrow R is turned by the cutter blade 21.
Turn direction.

The forefront of the tip 10C of the cutter blade 21
In the range from the end portion to the intermediate portion 10B, the cutter blade 21
A cutting blade 22 is provided on the edge facing the rotation direction. Center 1
0A to a step portion near the center portion 10A of the intermediate portion 10B
When hooking, the two grooves 27, 27 are separated downward in the width direction.
It is provided so as to swell. The cutting blade 22 has a tip
To the opposite side of the rotation direction (opposite to the cutting blade 22)
Side) and inclined in a direction to recede toward the edge
Has been established.

The above-mentioned cutter blade 21 has a blast piece.
23 and the pressing piece 25 are provided integrally. Blast piece 23
Is the end opposite to the rotation direction of the cutter blade 21
Edge, that is, the front end including the tip of the edge opposite to the cutting blade 22
10C, and the blast pieces 23 are provided as follows.

The blast piece 23 has a valley 23a formed by a cutter blade.
In the mounting hole 21a forming the shaft hole of the rotating shaft of the blade 21
Center line passing through the center C (in the width direction of the cutter blade 21)
The core line) is inclined by an angle θ with respect to a line L2 parallel to L1.
A line L3 is formed, and this line L3 is used as a valley to make a valley fold and stand upward.
To be provided. The above blast pieces 23 are substantially triangular.
No, erected upwardly inclined, against the rotational direction surface 23
b is formed as an inclined surface.

On the other hand, the pressing piece 25 is
The edge opposite to the rotation direction of the blade 21, that is, the cutting blade 22
On the opposite edge, the edge on the side where the blast piece 23 is provided is
A bulging portion that is provided adjacent to the blast piece 23 and is an intermediate portion 10B.
24 at the edge. The depressing piece 25 is located at the intermediate portion 10B.
Provided so as to hang down at the edge of the bulging portion 24,
In the illustrated example, the shaft hole of the rotating shaft of the cutter blade 21 is configured.
The center line passing through the center C of the mounting hole 21a
Center line in the width direction of the blade 21) to a line L2 parallel to L1.
On the other hand, a line L4 inclined by the angle α is defined as a line L4.
It is provided so that it folds down as a (mountain) and hangs down.

The above-mentioned depressing piece 25 has a substantially triangular shape.
From the edge opposite to the direction of rotation
6 is configured as an inclined surface with respect to the rotation direction. This push
The lower end of the lowering piece 25 is a bulge formed at the intermediate portion 10B.
Center portion 10A of the cutter blade 21 excluding the portion 24, cutting
It is almost the same as the general surface of the tip 10C having the blade 22,
It is located above.

As shown in FIG. 5, a first inner member 31 and a second inner member 41, each of which is formed of a divided body, are detachably provided in the cutter housing 10 accommodating the above-described cutter blade 21 as necessary. ing. That is, as shown in FIG. 3, the first inner member 31 is
The lower inner portion is mounted on the outer peripheral side inner surface from the side portion to the front portion, and the inner side thereof is formed in an arc-shaped section 32, and the second inner member 41 is connected to the discharge duct section 1.
6, the inside of which is an arc-shaped section 42
Outlet blocking portion 4 which is formed in
3 are integrally provided.

Here, when the first inner member 31 is mounted in the scroll portion 12, the cutter housing 1
0 is formed. Also, the second inner member 41
Is a mulching kit for temporarily closing the discharge port 17 and performing a mulching action. As shown in FIGS. 6 and 7, the arc-shaped section 32 inside the first inner member 31 has
A plurality (three in the figure) of guide ribs 33, 34, and 35 extending upward from below along the blade rotation direction R are formed at intervals, and as shown in FIG. A guide rib 45 continuous with the guide rib 35 is also formed on the arcuate section 42 inside the second inner member 41 that is continuous with the second inner member 41.

The above guide ribs 33, 34, 35, 45
Has a surface shape facing the cutting blade 22 of the cutter blade 21, whereby the arc-shaped cross sections 32 and 42 are
The steps are bordered by the guide ribs 33, 34, 35, 45. Note that the guide ribs 45 need not necessarily be provided on the second inner member 41, and the first inner member 3
Even with only one guide rib 33, 34, 35, the turf can be sufficiently shredded. Further, the first inner member 31 and the second inner member 41 may be used separately.

The first inner member 31 and the second inner member 41 are made of a synthetic resin, and the first inner member 31 is formed on the upper surface of the inner surface of the scroll portion 12 and the inner surface of the peripheral wall portion 15 as shown in FIG. The cutter housing 1 comes into contact with the bolts 36... And nuts 37.
Mounted within 0. And the second inner member 41
As shown in FIGS. 3 to 5, a metal cover 51 for covering the discharge port 17 from the outside is provided with bolts 46.
, And fitted on the inner surface of the discharge duct 16, and the upper piece of the metal cover 51 is bolted to the bolt 52 on the upper surface of the discharge port 17.
And the nut 53 are attached to the inside of the cutter housing 10.

The following lawn mowing operation will be described. First, as shown in FIGS. 3 and 4, when both the first inner member 31 and the second inner member 41 are mounted in the cutter housing 10,
The cut turf cut by the cutting blades 22, 22 of the cutter blade 21 rotating in the R direction rises upward by the blast action of the blast pieces 23, 23 as shown by arrows in FIG. 1st inner member 31 and 2nd inner member 4
It moves to the lower surface side of the central portion of the housing upper wall portion 11 along the two arc-shaped portions 32, 42 of the two sections.

At this time, the arc-shaped portions 32 and 42 of both cross sections have
Since the guide ribs 33, 34, 35, and 45 are provided so as to face from the lower side to the upper side along the blade rotation direction R and face the cutting blade 22 of the cutter blade 21, the cut grass is formed by the guide ribs 33, 34, 35, 4
5 is effectively moved inward from above.

The cut grass is accelerated by the air suction from the air intakes 13 of the housing upper wall portion 11 to fall on the swirl locus of the bulging portions 24, 24 of the cutter blade 21, and the cutting blade 22 is cut. , 22 are again cut into small pieces, and then both inclined surfaces 2 are directed toward the blade rotation direction R of the press-down pieces 25, 25 provided on the blade bulging portions 24, 24 and toward the rotation center of the cutter blade 21.
According to 6, 26, the cut turf after shredding is uniformly dispersed toward the vicinity of the blade rotation center and falls onto the turf as shown by the arrow in FIG.

Further, with respect to the cutter blade 21, the blast pieces 23, 23 above the both ends thereof are as described above.
Since the cutting turf cut by the cutting blades 22 and 22 at both ends thereof rises upward once and rises upward, as shown by arrows in FIG. Part 2
It flows so as to fall on the cutting blades 22, 22 on the 4, 24 side.

The push-down piece 2 on the side of the bulging portions 24, 24
4, 5 and 25 have a substantially triangular shape in plan view and have inclined surfaces 26 and 26 directed toward the center of rotation like an axial fan shape. As shown by, the wind actively flows to the cutting blades 22, 22 on the side of the bulging portions 24, 24, whereby the shredding performance of the cut grass can be enhanced. As shown by, uniform dispersion performance toward the center of rotation of the cut grass is obtained. Therefore, the ground turf can be dropped more uniformly below the turf than before.

Here, the upward bulging portion 24 is dropped downward.
As described above, the press-down piece 25 is formed so as to be lowered.
Since the lower end of the cutter blade 21 is located substantially at the same level as or higher than the general surface of the cutter blade 21, a downward wind flow can be obtained without falling down of the turf, and good mowing performance can be secured. Further, as shown in FIG. 10, the cutting blade 21 is gradually inclined so as to recede in the direction opposite to the rotation direction toward the tip thereof, that is, the cutting ability with respect to the turf can be improved.

The cutter blade 21 is provided with a stepped portion formed by the bulging portions 24 between the intermediate portion and the rotation center portion. Can be alleviated by the step, so that impact transmission to the rotary power system can be avoided. In addition, since the two recessed grooves 27, 27 extending over the stepped portion are provided between the upward bulging portion 24 and the central portion, rigidity at the stepped portion is also ensured.

Further, even if the second inner member 41 in the discharge duct 16 is removed and the discharge port 17 is opened while the first inner member 31 is provided in the scroll portion 12, the first inner member 31 can be opened. And the guide ribs 33, 34, 35 of the cross section can provide the function of guiding the cut grass, that is, the cut grass can be shredded in substantially the same manner as described above. One part of the cut grass is discharged toward
As shown in the figure, the cut grass can be stored in the gravel bag 19 at the rear of the machine body 1 via the shooter 18.

At the time of the discharge to the side, the discharge duct 16 is connected to the end of the first inner member 31 by the scroll portion 12.
To the point P (see FIG. 3) on the outer peripheral side that is continuous in the tangential direction, and does not protrude into the discharge duct portion 16 without disturbing the smooth flow of wind in the discharge duct 16. Good release and storage of the cut grass can be obtained. In this way, it is possible to cope with the side discharge and storage in the glass bag 19 while promoting shredding of the cut grass.

In the case of increasing the air flow and performing simple side discharge or storing the cut grass in the graffle bag 19, the cutter housing 10 is not used as shown in FIG. By using the scroll portion 12 as it is, the air volume in the scroll portion 12 can be secured, and the cut grass can be discharged to the side from the discharge port 17, and the cut grass can be stored in the glass bag 19.

By the way, in the lawn mower of the embodiment, the state in which the inner member is mounted inside the scroll portion becomes a borens type cutter housing known in US Pat. No. 3,085,386. With the adoption of a boring-type cutter housing, the cut grass is gathered more and more upwards inside, and the cut grass is dropped from near the center. It becomes a mulching moor of the configuration.

Although the embodiment has been described based on a riding lawn mower, the present invention can be applied to other walking lawn mowers, and the detailed structure can be appropriately changed. Further, the cutter blade of the present invention can be applied not only to the mowing of the embodiment but also to other mowing.

[0035]

As described above, according to the present invention, with respect to the cutting blade provided from the end of the blade which rotates substantially horizontally to the intermediate portion near the center of rotation, the cutting edge is located at the rear end in the rotation direction. the Okoshikazehen 23 to provided in the cutter blade for grass mowing the wind in the middle of the rotation center portion nearer Okoshikazehen 23 provided depressed piece 25 that directs below this upward, Okoshikazehen 23 while the cutter blade 21 is rotating.
An angle θ with respect to a line L2 parallel to the center line L1 passing through the center axis
Using the inclined line L3 as a valley, make a valley fold and stand up and tilt
Being provided with a slope, the pushing-down piece 25 is
23 is provided adjacent to the edge on the side having
The piece 25 passes through the rotation center axis of the cutter blade 21.
With respect to a line L2 parallel to the center line L1
Valley with the line L4 as a valley
The so provided to comprise an inclined surface directed to wind the cut mowing Kusashiba in the cutting blade end, the Okoshikazehen 23 to tilt obliquely the upward, from once up above the middle part The inclined surface directed to the center of rotation of the push-down piece 25 is made to fall on the cutting blade, thereby promoting the flow of the wind to the cutting blade portion in the middle part, thereby improving the shredding property and the rotation center. The ground turf can be uniformly dispersed toward the portion, that is, the ground turf can be dropped more uniformly below the lawn than before.

Further, by gradually inclining the cutting blade 22 so as to recede in the direction opposite to the rotation direction toward the front end, it is possible to improve the cutting ability for grass and lawn.

Further, by providing a step between the intermediate portion and the center of rotation, the impact applied to the end can be reduced by the step.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a lawn mower as an example to which the present invention is applied;

FIG. 2 is a schematic plan view thereof.

FIG. 3 is a bottom view showing the inside of the cutter housing device.

FIG. 4 is a longitudinal rear view thereof.

FIG. 5 is an exploded perspective view of the inner member.

FIG. 6 is a partial perspective view showing a guide rib.

FIG. 7 is a sectional view taken along the line AA of FIG. 3;

FIG. 8 is a sectional view taken along the line BB of FIG. 3;

FIG. 9 is an enlarged perspective view of a half of a cutter blade according to the present invention, with a part cut away.

FIG. 10 is a plan view of a cutter blade .

[Explanation of symbols]

Reference Signs List 21: cutter blade, 22: cutting blade, 23: upward blast piece, 24: upward bulging part, 25: push-down piece, 23b, 26: inclined surface, 27: concave groove, R: rotation direction, C: Center of mounting hole for cutter blade , L1
... center line of cutter blade , L2 ... parallel to L1
Lines , L3, L4 ... broken lines of blast pieces, depressed pieces , θ,
α: Folding angle of blast piece and push-down piece.

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Yasuji Hashimoto 1-4-1, Chuo, Wako-shi, Saitama Pref. Honda Research Institute Co., Ltd. (56) References JP-A-4-148613 (JP, A) Showa 63-58543 (JP, U) Actually open Showa 63-26225 (JP, U) Actually open Showa 62-144431 (JP, U)

Claims (3)

(57) [Claims] 1. A substantially cutting blade 22 provided from the end portion of the blade to the intermediate portion of the rotation center portion closer to horizontal rotation, set as to stand in the edge portion of the rotation direction rear side with respect to the cutting blade 22 < and br /> digits electromotive Kazehen 23, for grass mowing the wind provided to droop and a depressed piece 25 to direct downward in an intermediate portion of the rotational center nearer electromotive Kazehen 23 of this cutter blade 21 smell Te, the Okoshikazehen 23, during rotation of the cutter blade 21
An angle θ with respect to a line L2 parallel to the center line L1 passing through the center axis
Using the inclined line L3 as a valley, make a valley fold and stand up and tilt
The press-down piece 25 is provided so as to have a slope, and the press-down piece 25
The press-down piece 25 is provided adjacent to the edge, and
Parallel to the center line L1 passing through the rotation center axis of the blade 21
A line L4 inclined by an angle α with respect to a line L2
A valley folds down and hangs downward to direct the wind toward the center of rotation
A grass cutter blade for cutting grass and grass , provided with a surface . 2. The grass blade according to claim 1, wherein the mowing blade portion 22 is gradually inclined so as to recede in a direction opposite to the rotation direction toward the tip. 3. The grass blade according to claim 1, wherein a step portion is provided between the intermediate portion and the rotation center portion.