JP2701163B2 - Lawn mower - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lawn mower provided with a discharge fan for transporting turf cut with a cutter blade.

[Conventional technology]

BACKGROUND ART A lawn mower mowers a lawn by, for example, rotating a cutter blade in a cutter housing by an engine mounted on the cutter housing.

And the grass cut in the cutter housing,
Due to the transport wind generated by the twist provided on the cutter blade, the blade is released from the outlet of the cutter housing to the outside, or is transported and stored in a rear glass bag via a shooter.

The cutter blade is usually a flat plate member having a rectangular shape in a plan view. The output shaft of the engine is mounted at the center, a blade portion is formed at the front edge in the rotation direction at both ends in the longitudinal direction, and the grass is transported to the rear edge in the rotation direction. A twist for raising wind is formed upright, and the blade is cut by the rotation of a cutter blade to cut grass, and a wind is generated at the twist portion.

Further, there is also known a cutter housing in which a discharge fan is disposed on a cutter blade. In this device, a discharge fan is fixed to an output shaft of an engine, and its rotation diameter is smaller than the rotation diameter of the cutter blade, and rotates at the same rotation speed as the cutter blade. The turf cut by the cutter blade is transported to, for example, a rear glass bag by the transport wind generated by the discharge fan together with the transport wind generated by the cutter blade.

[Problems to be solved by the invention]

Thus, in such a lawn mower, wind noise is generated when the cutter blade rotates. This is considered to be due to the turbulence generated by the twisted portion of the cutter blade when the cutter blade rotates, and to the collision of the cutter blade with the turbulence. Further, in the case of the apparatus provided with the discharge fan, since it rotates at the same high rotational speed as the cutter blade, wind noise is generated similarly to the cutter blade.

The present invention has been made in view of the above points, and can reduce wind noise at the time of mowing grass with a simple structure,
It is another object of the present invention to provide a lawn mower capable of improving lawn mowing performance and transporting performance.

[Means for solving the problem]

The configuration of the present invention is a lawn mower provided in the cutter housing with a discharge fan for transporting turf cut with a cutter blade in the cutter housing,
The cutter blade has only a lawn mowing function, and the rotation center of the discharge fan disposed above the cutter blade and the rotation center of the cutter blade are eccentric.

Preferably, the rotation center of the discharge fan is located forward or backward of the rotation center of the cutter blade.

Further, it is preferable that the rotation diameter of the discharge fan is equal to or larger than the rotation diameter of the cutter blade, and the rotation speed of the discharge fan is lower than the rotation speed of the cutter blade.

[Action]

The grass is cut by the rotation of the cutter blade, and the cut grass is conveyed by a discharge fan.

Since the cutter blade of the present invention does not form a twist for generating the lawn grass transport wind and has only the lawn mowing function, the wind noise can be suppressed even when rotating at high rotation, and the lawn mower is a discharge fan. Conveyed by. And, by eccentricizing the rotation center of the discharge fan and the rotation center of the cutter blade, the rotation speed of the discharge fan can be made lower than the rotation speed of the cutter blade through a simple deceleration mechanism, further reducing wind noise. Make it easily possible.

In addition, by disposing the center of rotation of the discharge fan ahead of the center of rotation of the cutter blade, the blades of the discharge fan can be easily arranged above or in front of the blade of the cutter blade, so that the turf can be cut by the discharge fan. In the raised state, the cutter blade can cut the grass,
Lawn mowing can be improved.

In addition, by disposing the center of rotation of the discharge fan behind the center of rotation of the cutter blade, the blades of the discharge fan can be closer to the discharge port provided at the rear of the cutter housing, so that the turf transfer performance is improved. can do.

〔Example〕

FIG. 1 is a side view of a walking lawn mower, FIG. 2 is a longitudinal sectional view of a main part thereof, and FIG. 3 is a plan view of the main part.

The lawn mower 1 is of a walking type. The engine 3 is mounted on the cutter housing 2, the output shaft 4 extends vertically downward through the central opening 5 of the upper wall 2a of the cutter housing 2, and the cutter blade 6 is fixed to the lower end thereof.

The cutter blade 6 is a rectangular flat plate member in plan view,
The output shaft 4 is fixed to the center, and the blades are formed at the side edges at both ends in the longitudinal direction. The cross section in the width direction has a parallelogram shape (see FIG. 7). The cutter blade 6 is not provided with a twist for raising the lawn turf transport wind at the side edges of both ends. The rotation of the cutter blade 6 cuts grass in the cutter housing 2, and the cut grass is conveyed by a large-capacity low-rotation discharge fan 7 disposed above the cutter blade 6 in the cutter housing 2.

The discharge fan 7 is arranged such that its rotation center is located ahead of the rotation center of the cutter blade 6 and is driven to rotate by the output shaft 4 via a speed reduction mechanism.

In the following, a gear 8 is fixed to the output shaft 4 above the cutter blade 6, and a ring gear 9 having internal teeth meshing with the gear 8 is fixed to a lower end of the engine 3 in a cylindrical shape. The gear support 10 is rotatably provided at a lower end portion thereof via a bearing 11. A discharge fan 7 is fixed to the outer periphery of the ring gear 9, and the rotation diameter of the discharge fan 7 is substantially the same as the rotation diameter of the cutter blade 6. The rotation center of the discharge fan 7, that is, the rotation center of the ring gear 9,
It is arranged forward of the center of rotation of the cutter blade 6, that is, the center of rotation of the output shaft 4. Therefore, the blade portion 7a of the discharge fan 7 is disposed so as to protrude forward from the blade portion of the cutter blade 6 in the traveling direction of the lawn mower 1.

Therefore, the power of the output shaft 4 is controlled by the gear 8 and the ring gear 9.
To the discharge fan 7 to drive the discharge fan 7 at reduced speed.

Therefore, the cutter blade 6 rotates at the same rotational speed as the output shaft 4, but the discharge fan 7 is decelerated and rotates at a lower speed than the cutter blade 6.

Reference numeral 12 denotes a shielding disk fixed to the output shaft 4, and a ring gear 9.
To prevent turf and the like cut by the cutter blade 6 from entering the ring gear 9.

13, 14 are wheels provided on the front and rear portions of the cutter housing 2, 15 is a handle extending rearward from the rear of the cutter housing 2, 16 is a discharge port provided on the rear of the cutter housing 2, and 17 is a cutter housing 2 This is a glass bag attached to the rear of the camera.

Therefore, when mowing, the engine 3
The cutter blade 6 rotates to cut grass, and the cut grass is conveyed from the discharge port 16 of the cutter housing 2 into the glass bag 17 by the large-capacity low-rotation discharge fan 7. At the time of mowing, as shown in FIG. 4, the lawn 18 is pushed down in the traveling direction at the front of the peripheral wall 2b covering the cutter blade 6 of the cutter housing 2, but the peripheral wall 2b of the cutter housing 2 is In the gap between the blade 6 and the tip, the turf 18 is raised by the discharge fan 7 above, and the turf 18 is cut by the cutter blade 6 in an upright state. For this reason, the turf reaping property is improved.

The cutter blade 6 is not limited to the above-described rectangular plate member (see FIG. 3).
For example, a parallelogram shaped plate member (see FIGS. 8 (A) and 8 (B)), an elongated rod-shaped plate member (see FIG. 8 (C)), and a pair of round bars protruding from a disk (FIG. 8 (C)). (See FIG. 8D). The cross-sectional shape in the width direction is preferably the above-described parallelogram shape (see FIG. 7) in terms of suppressing wind noise, but is not limited thereto.

Rotation diameter, rotation speed, blade 7a of discharge fan 7
The number, the height of the twist, etc. may be appropriately selected, but the number of blades 7a may be increased and the height of the twist may be increased as the rotation speed is reduced. As an example, 1500rpm
The blade 7a has six blades, the twist height of the blade 7a is 50 mm, and the twist shape of the blade 7a is 30 as shown in FIG.
放出, the emission angle β is configured to form a curved surface of 45 °.

Further, the speed reduction mechanism of the discharge fan 7 is not limited to the above-described one.

In the above example, the rotation center of the discharge fan 7 is disposed forward of the rotation center of the cutter blade 6. However, as shown in FIGS. 5 and 6, the rotation center of the discharge fan 7 is 6 may be arranged behind the rotation center. 2 and 3 are the same as those shown in FIGS. 2 and 3 except that the front and rear positions of the center of rotation of the discharge fan 7 and the cutter blade 6 are different. With this configuration, the discharge fan 7 can be disposed close to the discharge port 16 of the lawn grass, so that the transportability of the lawn grass can be improved.

〔The invention's effect〕

As described above, in the present invention, grass is cut by rotation of the cutter blade, and the cut grass is conveyed by the discharge fan.

Further, the cutter blade of the present invention has only a lawn mowing function without forming a twist for generating the lawn grass transporting wind, so that the wind noise can be suppressed even at high rotation. And, by eccentricizing the rotation center of the discharge fan and the rotation center of the cutter blade, the rotation speed of the discharge fan can be made lower than the rotation speed of the cutter blade through a simple deceleration mechanism, further reducing wind noise. Make it easily possible.

Further, by arranging the rotation center of the discharge fan forward of the rotation center of the cutter blade, it is possible to improve the lawn mowing performance.

In addition, by disposing the rotation center of the discharge fan behind the rotation center of the cutter blade, it is possible to improve the turf transfer performance.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment of the present invention, FIG. 1 is a side view of a walk-behind lawn mower showing an example of the present invention, FIG. 2 is a longitudinal sectional view of the main part, FIG. 4 is a partially enlarged view of FIG. 2, FIG. 5 is a vertical sectional view of a main part of a lawnmower showing another example, and FIG.
FIG. 7 is a plan view of the main part, FIG. 7 is a sectional view in the width direction of the cutter blade, FIG. 8 is a plan view of the cutter blade, and FIG. 9 is a view showing a part of the discharge fan. 1 is a lawn mower, 2 is a cutter housing, 2a is an upper wall, 2b is a peripheral wall, 3 is an engine, 4 is an output shaft, 5 is an opening, 6 is a cutter blade, 7 is a discharge fan, 7a is a blade,
8 is a gear, 9 is a ring gear, 10 is a gear support, 11 is a bearing, 12 is a shielding disc, 13 and 14 are wheels, 15 is a handle, 16 is an outlet, 17 is a glass bag, and 18 is turf.

Claims (4)

(57) [Claims] 1. A lawn mower having a discharge fan for transporting turf cut by a cutter blade in the cutter housing in the cutter housing, wherein the cutter blade has only a lawn mowing function, and is provided above the cutter blade. A lawn mower characterized in that the center of rotation of the discharge fan and the center of rotation of the cutter blade are eccentric. 2. A lawn mower having a discharge fan for transporting turf cut by a cutter blade in the cutter housing in the cutter housing, wherein the cutter blade has only a lawn mowing function, and is provided above the cutter blade. A lawn mower wherein the rotation center of the discharge fan to be disposed is disposed forward of the rotation center of the cutter blade. 3. A lawn mower having a discharge fan for transporting turf cut by a cutter blade in the cutter housing in the cutter housing, wherein the cutter blade has only a lawn mowing function, and is provided above the cutter blade. A lawn mower wherein the rotation center of the discharge fan to be disposed is disposed behind the rotation center of the cutter blade. 4. The lawn mower according to claim 1, wherein the rotation diameter of the discharge fan is substantially equal to or larger than the rotation diameter of the cutter blade, and the rotation speed of the discharge fan is reduced by the rotation of the cutter blade. A lawn mower characterized by having a lower speed than the speed.