JPH11168937A - Lawn mower having rotating blade and fixed blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lawn mower equipped with a rotating blade and a fixed blade and capable of efficiently performing operations to install and remove the rotating blade and the fixed blade and smoothly carrying out the fine adjustment of the cutting height of lawn grass. SOLUTION: This lawn mower is capable of loosening bolts 9 (four in total), removing the bolts 9, rotating a reel part 13, a fixed blade 11, a rotating plate 4, etc., as one body in the direction of an arrow 98 with a mounting shaft 3 as the center, sliding the reel part 13, fixed blade 11, rotating plate 4, etc., as the one body in the direction of the mounting shaft 3, forming a slender shaft part in the mounting shaft 3, sliding the reel part 13, fixed blade 11, rotating plate 4, etc., as the one body in the shaft direction, thereby locating a holder 2 at the slender shaft part of the mounting shaft 3, moving the reel shaft 13, fixed blade 11, rotating plate 4, etc., in the direction of an arrow 97, freeing the holder 2 through a notch formed in the holder 2 from the mounting shaft 3 and removing the reel part 13, fixed blade 11, rotating plate 14, etc., as the one body when removing the fixed blade 11 and reel part 13 from the body part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lawn mower having a rotary blade and a fixed blade, and more particularly to a detachable rotary blade and a fixed blade.

[0002]

2. Description of the Related Art A first prior art of a lawnmower having a rotary blade and a fixed blade is disclosed in Japanese Unexamined Patent Publication No. Hei 8-1.
The lawn mower disclosed in Japanese Patent No. 87022 is raised. FIGS. 8 and 9 show a lawn mower according to the first prior art. FIG. 8 is a side sectional view of the lawn mower, and FIG. 9 is a partially enlarged view of FIG.

The reel unit 13 rotates about a reel unit shaft 13J, and the reel unit 13 is provided with a plurality of rotary blades 12 spirally with respect to the reel unit shaft 13J. Body 8
A motor 19 is provided therein, and the reel unit 13 rotates by receiving the drive of the motor 19.

[0004] With the reel unit 13 rotated, the operator holds the handle 6 and runs the lawn mower in the direction of the arrow 90 on the lawn. The main body 8 is provided with a front wheel 21 and a rear wheel 22 for traveling. A fixed blade 11 is provided in the main body 8 at a position close to the rotation orbit of the rotary blade 12, and the lawn is cut by sliding the rotary blade 12 and the fixed blade 11.

Here, there is a case where the reel portion 13 is detached from the main body 8 in order to polish or replace the rotary blade 12. In the lawn mower according to the first related art, the bearings of the reel shaft 13J are held between the upper bearing holder 32 and the lower bearing holder 31 on both side surfaces of the main body 8. The upper bearing holder 32 is fixed to the main body 8, and the lower bearing holder 31 can be connected to and separated from the upper bearing holder 32.

A connection bolt 34 is screwed into and penetrated into the lower bearing holder 31, and the lower bearing holder 31 is integrally attached to the fixed blade 11 via the connection bolt 34. The fixed blade 11 is rotatable about a rotation shaft 33 in the direction of arrow 98. And
When removing the reel unit 13 from the main body 8, the fixing bolt 3
5 and fix the upper bearing holder 32 to the fixed blade 11
And rotate in the direction of arrow 98. FIG. 9 shows a state in which the upper bearing holder 32 and the fixed blade 11 are rotated in the direction of arrow 98. From this state, the reel unit 13 is removed from the main body 8.

[Second Prior Art] Next, as a second prior art of a lawnmower having a rotary blade and a fixed blade, Japanese Patent Application Laid-Open No. H08-208,878 is disclosed.
The lawnmower disclosed in JP-163914A is raised. 10 and 11 show partial side views of this lawn mower.

[0008] As shown in FIG.
6 is provided with a shaft 37, on which a mounting arm 36 is rotatably mounted. The fixed blade 11 is fixed to the mounting arm 36. Mounting arm 36
Is fixed to the frame 46 by the adjusting screw 41.

A bearing 47 provided on the reel shaft 13J of the reel unit 13 is supported by being sandwiched between a receiving base 39 and a pressing piece 38. The holding piece 38 is fixed to the frame 46 by a screw 40.

When removing the reel unit 13, the adjusting screw 4
1, the mounting arm 36 is pivoted about the shaft 37, and the holding piece 38 is released at the same time as the mounting arm 36. Thus, the reel unit 13 is removed.

As shown in FIG. 11, a front wheel 42 of the lawn mower is mounted on a front wheel support plate 43, and a lever 44 is provided on the front wheel support plate 43. The lever 44 projects outward through a slit 45 formed in the frame 46. By moving the lever 44 along the slit 45, the front wheel 42 moves up and down with respect to the frame 46, so that the lawn mowing height can be adjusted.

[0012]

In a lawn mower, a rotating blade and a fixed blade are sometimes detached from a main body in order to grind or replace the blade. Usually, both the rotary blade and the fixed blade are removed to perform polishing and replacement work.

In both the lawn mower according to the first prior art and the lawn mower according to the second prior art, after the reel portion 13 is removed from the main body, the fixed blade 11 is separately disassembled from the main body. Must be removed. Also, when setting the rotary blade and the fixed blade on the main body, it is necessary to separately attach each of them.

For this reason, there is a problem that the efficiency of attaching and detaching the rotary blade and the fixed blade is low. Further, after the mounting, the sliding between the rotary blade and the fixed blade must be adjusted, and the working efficiency is further reduced.

[0015] In addition, when removing thatch (with dead roots, stems and leaves of the turf accumulated in the lawn) from the lawn, a cutting blade is used. In the case of a lawn mower that can be used both for cutting and cutting, the rotating blade is removed, and the cutting blade is attached instead to perform the cutting work. When attaching a cutting blade, the fixed blade is not required, so the fixed blade is also removed at the same time as the rotating blade.

Each of the lawn mower according to the first prior art and the lawn mower according to the second prior art has a rotary blade,
Since the fixed blade cannot be removed integrally, it cannot be easily replaced with a switching blade, and the efficiency of attaching and detaching the rotary blade and the fixed blade is low.

Further, as shown in FIG. 11, in the lawn mower according to the second prior art, the front wheel 42 can be moved up and down by moving the lever 44 to adjust the lawn mowing height. . However, the lever 44 has the slit 4
5, so that it is not possible to adjust the lawn mowing height steplessly,
Cannot make fine adjustments.

For this reason, there is a lawn mower (not shown) that adjusts the lawn mowing height using a screw shaft and a screw hole. In such a lawn mower, a screw hole is formed in a holder for supporting the front wheel, and a screw shaft provided integrally with the adjustment knob is screwed into the screw hole. According to this mechanism, the holder that supports the front wheel moves up and down in accordance with the rotation of the adjustment knob, so that the lawn mowing height can be finely adjusted.

However, in the lawn mowing height adjustment using the screw shaft and the screw hole, grass or soil enters the screw hole and is caught in the mesh between the screw groove and the screw thread, so that the screw cannot rotate smoothly. There is.

Accordingly, the present invention provides a lawn mower having a rotary blade and a fixed blade, which can efficiently perform the attaching and detaching work of the rotary blade and the fixed blade, and can smoothly perform fine adjustment of the lawn mowing height. For the purpose of providing.

[0021]

A lawn mower having a rotary blade and a fixed blade according to claim 1 is provided on a main body,
In a lawn mower having a rotary blade having a rotary blade rotating about a rotary blade axis and a fixed blade of a rotary blade provided on a main body, a connecting portion for connecting the rotary blade axis and the fixed blade. A detachable portion that is detachable from the main body. The detachable portion formed on the connection portion is detached from the main body, so that the rotary blade and the fixed blade are integrally formed. Can be removed from the
It is characterized in that the rotary blade and the fixed blade can be integrally attached to the main body by attaching the detachable portion formed on the connecting portion to the main body.

According to a second aspect of the present invention, there is provided a lawn mower including the rotary blade and the fixed blade according to the first aspect, wherein the mower includes a detachable shaft provided on a main body and a large diameter portion. And a small-diameter portion, and a detachable shaft whose cross-sectional diameter at the small-diameter portion is smaller than the cross-sectional diameter at the large-diameter portion. A hole through which the large diameter portion of the shaft can penetrate, and an opening communicating with the hole are formed, and the opening diameter of the opening formed in the detachable portion is the large diameter portion of the detachable shaft. The diameter of the attachment / detachment shaft is smaller than the diameter of the attachment / detachment shaft, and larger than the diameter of the small diameter portion of the attachment / detachment shaft. The detachable part is attached to the main body in a state where it cannot be removed from the Attached to the body as an integrated,
By positioning the small-diameter portion of the detachable shaft in the hole formed in the detachable portion, the detachable portion is detached from the detachable shaft through the opening communicating with the hole, and the detachable portion is detached from the main body. The rotating blade and the fixed blade are integrally removed from the main body.

According to a third aspect of the present invention, there is provided a lawn mower having a rotary blade and a fixed blade according to the first or second aspect, wherein the first shaft rotatably provided on the main body of the lawn mower having the rotary blade and the fixed blade according to the first or second aspect. A first shaft having a first screw portion formed on the outer periphery, a second shaft rotatably provided on the main body, a second shaft having a second screw portion formed on the outer periphery, and a second shaft. A wheel whose position with respect to the main body changes according to the rotation of the first shaft. The first screw portion of the first shaft and the second screw portion of the second shaft mesh with each other to rotate the first shaft. Second by
The shaft rotates, and the position of the wheel with respect to the main body can be adjusted according to the rotation of the second shaft.

[0024]

According to the lawn mower having the rotary blade and the fixed blade according to the first aspect, the rotary blade and the fixed blade are integrally removed from the main body by detaching the detachable portion formed at the connecting portion from the main body. be able to. Also,
By attaching the detachable portion formed on the connection portion to the main body, the rotary blade and the fixed blade can be integrally mounted on the main body.

As described above, the rotary blade and the fixed blade can be integrally attached and detached, and the work of attaching and detaching the rotary blade and the fixed blade can be performed efficiently.

In the lawn mower having the rotary blade and the fixed blade according to the second aspect, the large-diameter portion of the detachable shaft is positioned in the hole formed in the detachable portion, so that the detachable portion is moved from the detachable shaft. Attach the detachable part to the main body in a state where it can not be removed,
The rotary blade and the fixed blade are integrally attached to the main body. In addition, by positioning the small-diameter portion of the detachable shaft in the hole formed in the detachable portion, the detachable portion is detached from the detachable shaft through the opening communicating with the hole, and the detachable portion is detached from the main body. Then, the rotary blade and the fixed blade are integrally removed from the main body.

Therefore, the detachable portion formed on the connecting portion is moved and positioned at the large diameter portion or the small diameter portion of the detachable shaft, so that the detachable portion is attached to the main body or the detachable portion is detached from the main body. be able to. Therefore, with a simple configuration, the rotary blade and the fixed blade can be easily and reliably attached and detached integrally, and the work of attaching and detaching the rotary blade and the fixed blade can be efficiently performed.

In the lawnmower having the rotary blade and the fixed blade according to the third aspect, the first screw portion of the first shaft and the second screw portion of the second shaft mesh with each other, and the first shaft is rotated. By doing so, the second shaft rotates, and the position of the wheel with respect to the main body can be adjusted according to the rotation of the second shaft.

Thus, the first screw portion of the first shaft and the second screw portion
Since the second screw portion of the shaft is meshed with the shaft and does not use, for example, a mechanism of the screw shaft and the screw hole, grass or soil does not enter the screw hole. Therefore, fine adjustment of the lawn mowing height can be performed smoothly.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a lawnmower having a rotary blade and a fixed blade according to the present invention will be described with reference to the drawings. FIG. 1 is a bottom view of the lawn mower according to the present embodiment,
FIG. 2 is a side view of the lawn mower, and is a partial cross-sectional view taken along the line Y1-Y1 shown in FIG. FIG. 3 is an enlarged view of the vicinity of the holder 2 shown in FIG. 2, and FIG. 4 is an enlarged view of the mounting shaft 3, the fixed blade 11, and the like shown in FIG.

FIGS. 5A and 5B are side views showing a state where the fixed blade 11 and the reel portion 13 are removed. FIG. 6 is a bottom view of the lawn mower with the attaching part 18 attached thereto,
FIG. 7 is a side view of the lawn mower, and is a partial cross-sectional view in the Y2-Y2 direction shown in FIG.

As shown in FIG. 2, the main body (main body) 8 has a motor 19 and a reel 13 built therein. Reel part 13
Rotates around a reel shaft 13J, which is a rotating blade shaft.
The reel unit 13 is provided with a plurality of rotary blades 12 in a spiral shape. The drive of the motor 19 is transmitted to the reel unit 13, and the reel unit 13 is driven to rotate.

With the reel unit 13 rotated, the operator holds the handle 6 and runs the lawn mower in the direction of the arrow 90 on the lawn. The main body 8 is provided with a front wheel 21 and a rear wheel 22. A fixed blade 11 which is a receiving blade of the rotary blade 12 is provided in a position close to the rotary orbit of the rotary blade 12 in the main body portion 8. Reap

Note that the cut grass is guided to the grass catcher 10 by the rotating wind of the reel unit 13.
The glass catcher 10 is detachable from the main body 8 so that grass accumulated inside can be removed.

The fixed blade 11 is fixed to the rotating plate 4 by bolts (see FIGS. 1 and 4), and holders 2 as detachable portions are provided at both ends of the rotating plate 4. The holder 2 is mounted on and supported by a mounting shaft 3 as a mounting / removing shaft provided in the main body 8, and the rotating plate 4 is rotatable about the mounting shaft 3 as a central axis. As shown in FIG. 3, a support hole 2H, which is a hole, is formed in the holder 2, and a cutout 2K as an opening is formed in communication with the support hole 2H.

The diameter of the support hole 2H is slightly larger than the diameter L1 of the large shaft portion 3a, which is the large diameter portion of the mounting shaft 3, and when the large shaft portion 3a of the mounting shaft 3 passes through the support hole 2H, The holder 2 and the rotation plate 4 are rotatable around the mounting shaft 3 as a central axis.

The notch diameter L3 of the notch 2K of the holder 2 is smaller than the diameter L1 of the thick shaft portion 3a of the mounting shaft 3. Therefore, the mounting shaft 3 is provided in the support hole 2H of the holder 2.
The holder 2 cannot be detached from the mounting shaft 3 when the thick shaft portion 3a of FIG. The notch diameter L3 of the notch 2K of the holder 2 is larger than the diameter L2 of the small shaft portion 3b, which is the small diameter portion of the mounting shaft 3.

As shown in FIG. 4, connection pieces 4G are integrally formed on both sides of the rotary plate 4, and connection bolts 16 penetrate the connection pieces 4G. The connection bolts 16 penetrating through the connection pieces 4G are screwed into the bearing holders 7, respectively. Bearing holder 7
Are located inside the both side surfaces of the main body 8 and the reel 1
The third reel portion shaft 13J is supported. In the present embodiment, the rotating plate 4, the connection bolt 16, and the bearing holder 7 for connecting the rotary blade 12 and the fixed blade 11 are connection portions.

By rotating the connecting bolt 16, the sliding of the rotary blade 12 and the fixed blade 11 can be adjusted. The connection bolt 16 is provided with a spring 15 between the bearing holder 7 and the connection piece 4G.
6. The rattling between the fixed blades 11 is eliminated, and accurate adjustment of the rubbing can be performed.

Two bolts 9 pass through each bearing holder 7, and these bolts 9 are screwed into bosses 14 on the main body 8 side. Since the bolt 9 is screwed into the boss 14 and tightened, the reel portion 13, the fixed blade 11 and the like are fixed in the state shown in FIG.

Here, the fixed blade 11 and the reel unit 13 may be detached from the main body 8 in some cases in order to polish or replace the fixed blade 11 and the rotary blade 12. The fixed blade 11 and the reel unit 1 are described below.
3 will be described in detail. When the fixed blade 11 and the reel unit 13 are detached from the main body 8, first, as shown in FIG.
Book). The fixed blade 11 and the reel unit 13
When performing the attachment / detachment work, the lawn mower is erected with the grass catcher 10 portion facing downward.

By removing the bolt 9, the reel unit 1
3, the fixed blade 11, the rotating plate 4 and the like can be integrally rotated about the mounting shaft 3 in the direction of arrow 98. FIG. 5B shows a state in which the reel unit 13, the fixed blade 11, the rotating plate 4, and the like are rotated. From this state, the reel unit 13, the fixed blade 11, the rotating plate 4, and the like are slid in the direction of arrow 95 shown in FIG. 4 to position the holder 2 on the thin shaft portion 3b of the mounting shaft 3.

As described above, the notch 2K of the holder 2
Notch diameter L3 is the diameter L2 of the thin shaft portion 3b of the mounting shaft 3.
Greater than. For this reason, by positioning the holder 2 on the thin shaft portion 3b of the mounting shaft 3, the reel portion 13, the fixed blade 11, the rotating plate 4 and the like are moved in the direction of arrow 97,
The holder 2 can be removed from the mounting shaft 3 through the notch 2K of the holder 2. Thus, the reel portion 13, the fixed blade 11, the rotating plate 4, and the like are integrally removed from the main body portion 8.

After the reel portion 13, the fixed blade 11, the rotating plate 4, and the like are integrally removed from the main body 8, the fixed blade 1
1. Polish or replace the rotary blade 12. Also, after removing the reel unit 13, the fixed blade 11, the rotating plate 4, and the like,
The notch 18 provided with the notch 17 can be attached to the main body 8.

FIGS. 6 and 7 show a state in which the switching part 18 is attached to the main body part 8. FIG. A bearing holder 27 having a structure similar to that of the bearing holder 7 is provided at both ends of the switching shaft 18J of the switching portion 18, and the bearing 9 is attached to the boss 1 by bolts 9.
Fix to 4.

Next, a procedure for attaching the reel unit 13, the fixed blade 11, the rotating plate 4, and the like to the main body 8 will be described. First, the notch 2K of the holder 2 is attached to the thin shaft portion 3b of the mounting shaft 3.
Then, the reel unit 13, the fixed blade 11, the rotating plate 4 and the like are moved in the direction of the arrow 96 (see FIG. 5B). As a result, 2H of the holder 2 is
Through K, it is fitted to the thin shaft portion 3b of the mounting shaft 3.

Thereafter, the reel portion 13, the fixed blade 11, the rotating plate 4 and the like are slid in the direction of the arrow 94 shown in FIG. 4 to position the holder 2 on the thick shaft portion 3a of the mounting shaft 3.
As described above, the notch diameter L3 of the notch 2K of the holder 2 is smaller than the diameter L1 of the thick shaft portion 3a of the mounting shaft 3. For this reason, by positioning the holder 2 on the thick shaft portion 3a of the mounting shaft 3, the reel unit 13, the fixed blade 11, the rotating plate 4 and the like cannot be detached as a unit so that the main unit 8 cannot be removed.
Can be attached to Then, the reel unit 13, the fixed blade 11, the rotating plate 4, and the like are rotated in the direction of the arrow 97 (FIG. 5B), and the bearing 9 is fixed to the switching blade 17 by screwing the bolt 9.

As described above, the reel portion 13, the fixed blade 11, the rotating plate 4, and the like are integrally attached to and detached from the main body portion 8. Therefore, the work of attaching and detaching the rotary blade 12 and the fixed blade 11 can be performed efficiently. Further, since the reel portion 13, the fixed blade 11, the rotating plate 4, and the like are integrally attached and detached, the distance between the rotating blade 12 and the fixed blade 11 does not change at the time of attachment and detachment. For this reason, it is not necessary to operate the connection bolt 16 to readjust the rubbing, so that the attaching / detaching operation can be performed more efficiently.

Next, a mechanism for adjusting the lawn mowing height in this embodiment will be described. As shown in FIGS. 1 and 2,
The front wheel 21 is rotatably supported by a front arm 23. The front arm 23 is attached so as to be rotatable with respect to the front arm shaft 24.

The front arm 23 has a second
A worm wheel 25 as a shaft is integrally fixed. The screw portion formed on the outer periphery of the worm wheel 25 is the second screw portion in the present embodiment. The worm wheel 25 is also supported rotatably with respect to the front arm shaft 24.

On the other hand, an adjustment knob 20 is provided on the upper surface of the main body 8. The adjustment knob 20 can be rotated with respect to the main body 8, and a worm gear 26 as a first shaft is fixed to the holder 2 in the main body 8.
The screw portion formed on the outer periphery of the worm gear 26 is the first screw portion in the present embodiment. The worm gear 26 and the worm wheel 25 are meshed with each other.

That is, the worm wheel 25 can be rotated via the worm gear 26 by rotating the adjustment knob 20. Then, as the worm wheel 25 rotates, the front arm 23 rotates around the front arm shaft 24.

By rotating the front arm 23 in this manner, the front wheel 21 can be moved up and down.
When the front wheel 21 moves up and down, the height from the ground to the rotary blade 12 and the fixed blade 11 changes, so that the lawn mowing height can be adjusted. The helical angle between the worm gear 26 and the worm wheel 25 is set so that the worm gear 26 is self-locked. Since the worm gear 26 is self-locked, the worm gear 26 does not rotate by the force from the worm wheel 25 side. For this reason, the adjusted cutting height does not fluctuate due to vibration of the front wheel 21 or the like.

As described above, since the worm wheel 25 and the worm gear 26 are engaged with each other and do not use, for example, a mechanism of a screw shaft and a screw hole, grass or soil does not enter the screw hole. Even if turf and soil are mixed in the meshing portion between the worm wheel 25 and the worm gear 26, if the adjustment knob 20 is rotated, the grass and soil fall off the meshing portion. Therefore, fine adjustment of the lawn mowing height can be performed smoothly.

The lawnmower having the rotary blade and the fixed blade according to the present invention is not limited to the one shown in the above embodiment. For example, although the rotating plate 4 has been illustrated as the connecting portion, any shape or structure may be used as long as it connects the rotating blade and the fixed blade, regardless of its shape or structure. May be used.

Although the holder 2 has been illustrated as an example of the attachment / detachment section, any shape and structure may be used as long as it can be attached / detached to / from the main body. In addition, support holes 2
H is illustrated, and the notch 2K is illustrated as the opening,
Other shapes and the like can be adopted.

The worm gear 26 serves as the first screw shaft.
And the worm wheel 25 as the second screw shaft. However, other shapes and the like may be used as long as they are rotatably provided on the main body and have the first screw portion and the second screw portion, respectively. Further, another screw or gear may be interposed between the first screw shaft and the second screw shaft to indirectly mesh the first screw portion and the second screw portion.

[Brief description of the drawings]

FIG. 1 is a bottom view of a lawnmower having a rotary blade and a fixed blade according to the present invention.

FIG. 2 is a side view of the lawn mower shown in FIG. 1, and is a partial cross-sectional view taken along a line Y1-Y1 shown in FIG.

FIG. 3 is an enlarged view of the vicinity of a holder 2 shown in FIG.

FIG. 4 is an enlarged view of a mounting shaft 3, a fixed blade 11, and the like shown in FIG.

FIGS. 5A and 5B are side views showing a state where the fixed blade 11 and the reel unit 13 are removed.

FIG. 6 is a bottom view of the lawn mower with the attaching portion 18 attached.

FIG. 7 is a side view of the lawnmower, and is a partial cross-sectional view in the Y2-Y2 direction shown in FIG.

FIG. 8 is a side sectional view of a lawnmower having a rotary blade attaching / detaching mechanism according to a first conventional technique.

9 is a partially enlarged view of the vicinity of a reel unit 13 of the lawn mower shown in FIG.

FIG. 10 is a partial side view in the vicinity of a reel unit 13 of a reel-type lawn mower according to a second related art.

FIG. 11 is a partial side view in the vicinity of a rotation plate of a reel-type lawn mower according to a second conventional technique.

[Explanation of symbols]

 2 Holder 2H Through hole 2K Notch 3 Mounting shaft 3a Thick shaft 3b Thin shaft 4 ···· Rotating plate 8 ··· Main body 12 ··· Rotating blade 13J ··· Reel shaft 21 ··· Front wheel 25 ··· Worm wheel 26 · .... Worm gears

Claims (3)

[Claims] 1. A lawn mower having a rotary blade provided on a main body and rotating about a rotary blade shaft, a fixed blade provided on the main body, and a lawn mower having a fixed blade. A connection portion for connecting the fixed blade, wherein the connection portion is formed with a detachable portion detachable from the main body, by detaching the detachable portion formed on the connection portion from the main body, The rotary blade and the fixed blade can be integrally removed from the main body, and the rotary blade and the fixed blade can be integrally mounted on the main body by attaching the detachable portion formed in the connection portion to the main body. Lawn mower having a rotating blade and a fixed blade. 2. A lawn mower having a rotary blade and a fixed blade according to claim 1, wherein the detachable shaft provided on the main body has a large-diameter portion and a small-diameter portion, and has a cross-sectional diameter at the small-diameter portion. Has a detachable shaft smaller than the cross-sectional diameter of the large-diameter portion. The detachable portion formed in the connecting portion has a hole through which the large-diameter portion of the detachable shaft can pass, and An opening communicating with the hole is formed, and an opening diameter of the opening formed in the attachment / detachment portion is smaller than the diameter of the large diameter portion of the attachment / detachment shaft, and a small diameter portion of the attachment / detachment shaft. By positioning the large diameter portion of the detachable shaft in the hole formed in the detachable portion, the detachable portion is attached to the main body in a state where the detachable portion cannot be detached from the detachable shaft. , The rotating blade and the fixed blade are integrally attached to the main body, By positioning the small-diameter portion of the detachable shaft in the hole, the detachable portion is removed from the detachable shaft through the opening communicating with the hole, and the detachable portion is detached from the main body. A lawn mower having a rotary blade and a fixed blade. 3. A lawn mower having a rotary blade and a fixed blade according to claim 1 or 2, wherein the first shaft is rotatably provided on the main body, and a first screw portion is formed on an outer periphery. A first shaft, a second shaft rotatably provided on the main body, a second shaft having a second threaded portion formed on an outer periphery, a wheel whose position with respect to the main body changes according to rotation of the second shaft, The first threaded portion of the first shaft and the second threaded portion of the second shaft are engaged with each other. By rotating the first shaft, the second shaft is rotated. The position of a wheel with respect to a main body can be adjusted according to rotation, The lawn mower having a rotary blade and a fixed blade.