JPS6320273Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a lawn mower that mows lawns by rotating a rotary blade (reel blade) using rotational torque generated by a motor.

[Background technology]

In a reel-type lawn mower consisting of a blade and a fixed receiving blade, the cutting ability of the lawn mower is evaluated by the gap between the blade and the fixed receiving blade. This gap adjustment is performed by rotating the fixed blade support plate 24 to which the fixed receiving blade 4 is fixed using the gap adjustment knob 20 (see Fig. 5) provided on the main body 6 around the support shaft 27 of the main body 6. However, conventionally, the fixed receiving blade 4 is simply attached to the fixed blade support plate 24 with the screw 25, and the inner diameter of the through hole 26a through which the screw 25 is inserted is not exactly the same as the outer diameter of the screw 25. Because of the looseness between the two, it is very difficult to attach the receiving blade edge of the fixed receiving blade 4 parallel to the cutting edge of the blade 2 (cylindrical), as shown in Fig. 8. The fixed receiving blade 4 was prone to tilt from the correct position indicated by the line.
If the cutting edge of the fixed receiving blade 4 is not installed parallel to the rotation axis of the rotary blade 3, no matter how much adjustment knob 20 is used to adjust it, the gap will not be uniform over the entire length of the blade 2 due to parallel misalignment. However, there was a problem in that phenomena such as deterioration of sharpness and partial cutting failure occurred.

[Purpose of invention]

The present invention has been made in view of the above points, and its purpose is to provide a reel-type lawn mower consisting of a rotating blade with a twisted blade and a fixed receiving blade. To provide a lawn mower that can accurately set the relative positioning with respect to a blade at the time of installation and has good sharpness.

[Disclosure of invention]

In the lawn mower according to the present invention, a fixed blade support plate 24 is provided to face a cylindrical rotary blade 3 to which a plurality of blades 2 are attached, and a fixed blade support plate 24 is provided on the fixed blade support plate 24.
are attached with screws 25, a plurality of protrusions 24a for positioning are provided on one of the fixed blade support plate 24 and the fixed receiving blade 4, and a plurality of through holes 26b for positioning are bored in the other. , each protrusion 2
The protrusion 24a and the through hole 26b are fitted into each other by making the width in the circumferential direction of the outer peripheral surface of the rotary blade 3 of 4a equal to the width in the circumferential direction of the outer peripheral surface of the rotary blade 3 of each through hole 26b. The fixed receiving blade 4 is held parallel to the outer circumferential surface of the rotary blade 3 by holding the fixed receiving blade 4 in parallel with the outer peripheral surface of the rotary blade 3, and the fixed receiving blade 4 is held relative to the blade 2 by fitting the protrusion 24a and the through hole 26b. The present invention will be described in detail below with reference to examples.

The rotary blade 3 for mowing the grass, the fixed receiving blade 4, the drive motor 5, etc. are housed in the main body 6, and the main body 6 is held by holding the handle 7, and the front and rear wheels 8,
9 to cut grass, etc. while moving, and by moving the cutting height adjustment lever 10 back and forth, the height of the front wheels 8 can be raised and lowered to adjust the cutting height of the grass, etc. The cut grass and the like are collected in a grass collection basket 11 at the rear of the main body 6.
Further, the switch 12 is provided at the upper end of the handle 7.

The rotary blade 3 has a highly rounded drum shape with a plurality of twisted blades 2 between a pair of opposing blade mounting plates 1, as shown in FIG. It is rotatably attached via a bearing 32 between a pair of rigid frames 30 and 31 within the main body 6. The fixed blade 4 is attached to another fixed blade support plate 24 built into the main body 1 to facilitate repair or replacement when it becomes necessary to polish or replace it due to wear, deformation, etc. during use. It is fixed with a screw 25, and the through hole 26a for screwing is fixed with the screw 25.
is larger than the diameter of

In the conventional example described above, the blade 2 is used for this purpose.
It was very difficult to attach the receiving blade edge part 26c of the fixed receiving blade 4 parallel to the cutting edge part (cylindrical shape) of the fixed receiving blade 4, but the present invention has a structural feature as shown in Fig. 4. . That is, first, in addition to the through hole 26a for screwing, two or more through holes 26b for positioning are provided in the fixed receiving blade 4 at appropriate intervals at positions parallel to the receiving blade tip 26c. be. The distance l ₁ between the through holes 26b at both ends is the length l of the fixed receiving blade 4.
It is desirable that 1/2 or more (l ₁ > 1/2l) of the through hole 26
The shape of b may be an elongated hole in the longitudinal direction of the stationary receiving blade 4 as shown in FIG. 4a, or a round hole as shown in FIG. 4c. Second, as shown in FIG. 4b, the fixed blade support plate 24 is provided with a positioning protrusion 24a that fits into the through hole 26b provided in the fixed blade 4 without play. It is provided in a position parallel to an imaginary line 24c connecting the centers of two holes 24b through which the support shafts 27 provided at both ends of the support shaft 27 pass. In other words, the circumferential width D of the outer circumferential surface of the rotary blade 3 at each protrusion 24a is equal to the circumferential width W of the outer circumferential surface of the rotary blade 3 at each elongated through hole 26b. Thus, the protrusion 24a and the through hole 26b are fitted together without play. The screw 25 is the fixed receiving blade 4
It is screwed to the fixed blade support plate 24 through the through hole 26a, and the inner diameter of the through hole 26a and the screw 25
If the outer diameters of the two are the same, it will be difficult to screw them together.
Generally, the inner diameter of the through hole 26a is made larger than the outer diameter of the screw 25, so that it is dimensioned to prevent looseness. Since it is simply fitted, there is no particular problem in forming the through hole 26b and the protrusion 24a to have approximately the same diameter and fitting them together without play. In addition, when the through hole 26b is formed in the shape of a long hole as shown in FIG.
The through hole 26b and the protrusion 2 are provided with a margin in the longitudinal direction.
4a can be absorbed. Also, in the above-mentioned case, the through hole 26b is provided on the fixed receiving blade 4 side.
Although the embodiment in which the protrusions 24a are provided on the fixed blade support plate 24 side has been described, the reverse is also possible. The fixed blade support plate 24 is a pair of frames 3
The rear part of the fixed blade support plate 24 is rotatably supported within the main body 6 by a support shaft 27 provided parallel to the reel shaft 14 between 0 and 31, and the front part of the fixed blade support plate 24 is adjusted by inserting a spring 28. Main body 6 with bolt 29
It is suspended from the top surface, and a gap adjustment knob 20 is screwed onto the upper end of the adjustment bolt. As shown in FIG. 5, the gap between the stationary receiving blade 4 and the blade 2 of the rotary blade 3 can be adjusted appropriately by turning the gap adjustment knob 20.

Thus, the power of the motor 5 is transmitted to the reel shaft 14 via the pulley 21a, the belt 21b, etc. to rotate the rotary blade 3, and the power is introduced into the gap between the cutting edge of the blade 2 and the cutting edge of the stationary receiving blade 4. The cut grass and the like are cut by the blades, and the cut grass is collected in the grass collection basket 11 by the centrifugal force of the rotary blade 3 and the wind force generated by the blade 2.

To adjust the gap between the blade 2 and the fixed receiving blade 4, use the gap adjustment knob 20 provided on the main body 6 to adjust the fixed blade support plate 24 on which the fixed receiving blade 4 is fixed to the main body 6.
The fixed receiving blade 4 side is provided with two or more positioning holes 26b at positions parallel to the receiving blade tip 26c. Since a positioning protrusion 24a that fits into the through hole 26b without play is provided on the fixed blade support plate 24 side in a position parallel to the support shaft 27, as shown in FIG. By assembling the fixed receiving blade 4 and the rotary blade 3 together, the parallelism of the fixed receiving blade 4 and the rotary blade 3 can be easily ensured. Therefore, by adjusting the gap with the two gap adjustment knobs 20, a uniform gap can be obtained over the entire length of the blade 2, and in case of trouble during use, the fixed receiving blade 4 can be replaced with a new fixed receiving blade 4. It can be easily reproduced when the need arises, and good sharpness and sharpness life can be ensured.

As is clear from the above, in the lawn mower of the present invention, a fixed blade support plate 24 is provided facing the cylindrical rotary blade 3 to which a plurality of blades 2 are attached, and the fixed blade support The fixed receiving blade 4 is attached to the plate 24 with screws 25, and a protrusion 24a for positioning is provided protrudingly on one of the fixed blade supporting plate 24 and the fixed receiving blade 4, and a through hole 2 for positioning is provided on the other.
6b and fit the protrusion 24a and the through hole 26b to connect the fixed receiving blade 4 to the rotary blade 3.
It has a configuration in which it is held parallel to the outer circumferential surface of.

[Effect of idea]

In the present invention, as described above, a plurality of protrusions for positioning are provided on one of the fixed blade support plate and the fixed receiving blade, and a plurality of through holes for positioning are bored in the other. Then, the width in the circumferential direction of the outer circumferential surface of the rotary blade of each protrusion is made equal to the width in the circumferential direction of the outer circumferential surface of the rotary blade of each through-hole, and the protrusion and the through-hole are fitted into each other. As a result, the fixed receiving blade is held parallel to the outer peripheral surface of the rotary blade, so the position of the fixed receiving blade can be regulated by fitting the positioning protrusion and the positioning through hole.
Moreover, since the protrusion and the through hole are used only for positioning, there is no rattling like with screws, and when installing the fixed receiving blade, it is possible to ensure that the relative position of the fixed receiving blade and the rotary blade is in the appropriate position. This has the effect that there is no parallel deviation of the fixed receiving blade, allowing continuous contact of the cutting edge, and ensuring optimum cutting quality at all times. In addition, since the cutting edge of the fixed receiving blade can be easily installed and adjusted parallel to the blade rotation center,
Even when replacing with a new fixed receiving blade due to trouble during use, the adjusted state can be easily reproduced.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the present invention;
The figure is a sectional view of the main body as above, Fig. 3 is a partially broken bottom view of the main body as above, Fig. 4 a is an exploded perspective view of the rotary blade and fixed receiving blade portion as above, and Fig. 4 b is as above. Fig. 4c is a perspective view showing another example of the fixed blade support plate, Fig. 5 is an assembled view of Fig. 4a, Fig. 6 is a bottom view of the same, Fig. 7 The figure is a schematic view showing the adjustment state of the fixed receiving blade, and FIG. 8 is a bottom view showing the drawbacks of the conventional example. 2 is a blade, 3 is a rotating blade, 4 is a fixed receiving blade, 2
4 is a fixed blade support plate, 24a is a protrusion for positioning, 25 is a screw, and 26b is a through hole for positioning.

Claims (1)

[Scope of utility model registration request] A fixed blade support plate is provided to face a cylindrical rotary blade to which a plurality of blades are attached, a fixed receiving blade is attached to the fixed blade supporting plate with screws, and one of the fixed blade supporting plate and the fixed receiving blade is provided. A plurality of protrusions for positioning are provided protrudingly on one side, and a plurality of through holes for positioning are bored on the other side. A lawn mower in which a fixed receiving blade is held parallel to the outer circumferential surface of the rotary blade by making the circumferential width of the outer circumferential surface of the rotary blade equal and fitting a protrusion and a through hole into each other.