JP2001178238A - Cutting edge-protecting tool of lawn mower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting edge-protecting tool of a lawn mower capable of preventing solid obstacles from being flicked away by a circular saw or preventing the cutting edge from being rebuffed by obstacles or preventing chipping of the cutting edge by preventing direct contact of obstacles at a mowing place with cutting edge of the circular saw. SOLUTION: This cutting edge-protecting tool is equipped with a disk 12 rotatably attached to the lower side of circular saw around a rotating shaft 4 of the circular saw 2 and having a diameter smaller than that of blade bottom circle of the above circular saw 2 and protrusions 13 protruded on more outer side than peripheral circle of the circular saw 2 at an adequate pitch in the circumferential direction on the peripheral part of the disk 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade protector for a mower, and more particularly, to preventing a circular saw from directly contacting an obstruction of a mowing field, and removing a hard obstruction with a circular saw. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade protector for a mowing machine, which makes it difficult for a blade to be flipped back to an object or chipped.

[0002]

2. Description of the Related Art As shown in an exploded side view of FIG. 12, a generally used mower includes a shaft frame 101, a circular saw 102 rotatably supported at the lower end thereof, and a circular saw 102 supported at an upper end of the shaft frame. The circular saw 102 and the shaft frame 101
It is driven by the engine or the motor via a drive shaft rotatably inserted into the inside.

At the lower end of the shaft frame 101, a gear box 103 is provided.
A circular saw rotary shaft 104 interlockingly connected to the drive shaft protrudes from the lower surface of the rotary shaft 3.
The collar 105 and the circular saw 102 are externally fitted on top of each other,
Tightening means 1 screwed to the lower end of the circular saw rotating shaft 104
The collar 105 and the circular saw 102 are fixed to the circular saw rotating shaft 104 by tightening the reference numeral 06.

The tightening means 106 includes a hexagonal nut 107 which is screwed with a box wrench, a washer 108 which is tightened together with the collar 105 and the circular saw 102, and a lower end of the hexagonal nut and the circular saw rotary shaft 104. And an annular cap 109 welded to the washer 108 in order to protect the washer 108.

[0005]

By the way, in the conventional mowing machine, the cutting edge of the circular saw divided between the trees comes into contact with hard obstacles such as pebbles rolling on the ground and stones exposed from the ground. , The obstacle is flipped around,
There is a problem that the cutting edge is repelled or the cutting edge is chipped.

[0006] The present invention solves this problem of the prior art,
Prevents direct contact between the blades of the mowing ground and the blade of the circular saw, making it harder for hard obstacles to be blown off by the circular saw, the blade to be flipped over by obstacles, or the blade to be chipped. It is an object of the present invention to provide a blade protector for a mowing machine.

[0007]

In order to achieve this object, a blade tip protector of a mower according to the present invention is mounted below a circular saw of the mower so as to be rotatable about a circular saw rotating shaft. A circular disc having a smaller diameter than the blade bottom diameter of the circular saw, and a protruding portion protruding outside the outer circular circle of the circular saw at an appropriate pitch in the circumferential direction at an outer peripheral portion of the circular plate. It adopts the technical means of:

According to this, since the disk is rotatably mounted around the circular saw rotating shaft of the mower, its rotational position (phase) is unspecified regardless of the circular saw phase. Become.
Therefore, the projection protruding around the disk also faces an unspecified phase irrespective of the phase of the circular saw.

As described above, the direction of the projection is unspecified,
In addition, because the circular saw can be rotated freely around the rotation axis of the circular saw, if the circular saw positioned almost horizontally is oscillated in an arc shape, the protrusions are easily divided between the grasses, and the phase is automatically adjusted. Is set. Then, the vegetation passes between the protruding portions having the determined phases and enters between the cutting blades of the circular saw without any trouble, and is cut off.

When the circular saw of the mower is swung in an arc shape,
Among the objects such as stones rolling on the ground surface, those that are higher than the height of the disk contact the cutting edge protector of the present invention or the cutting edge of the circular saw as obstacles, but the obstacles of the present invention among the obstacles The contacting object does not interfere with the cutting edge protector of the present invention, or is moved by being pushed by the cutting edge protector of the present invention, so that the circular saw does not violently blow it off.

[0011] Of the obstacles, those that come into contact with the circular saw without contacting the present invention almost always hit the projection of the present invention immediately after being vigorously blown off by the circular saw,
An attempt is made to rotate the present invention, which is buffered by the vegetation between the projections of the present invention. Since the momentum at which the obstacle flies is attenuated by this buffering action, the obstacle is less likely to be bounced outward from the present invention.

An object partly buried in the ground and another part exposed on the ground also becomes an obstacle when the exposed height of the disk increases. Of the obstacles of this type, those that come into contact with the cutting edge protector of the present invention press the cutting edge protector of the present invention,
If the circular saw is to be moved further, the circular saw can be moved around the point of contact between the obstacle and the cutting edge protector of the present invention, but is moved closer to the obstacle. I can't let that happen. That is, since a certain distance or more is maintained between the obstacle and the circular saw, the obstacle does not contact the circular saw.

Among the obstacles of this type, those which contact the circular saw without contacting the cutting edge protector of the present invention, flip the circular saw back in the tangential direction of its rotation. Since the grass stems and small tree trunks left behind during the course buffer the impact, the shock that the circular saw is flipped back is small.

In short, according to the present invention, many obstacles lurking in the mowing field are obstructed by the projections, making it difficult to directly contact the circular saw, and the obstacles contact the circular saw from between the projections. Then, when it is flipped off by the recoil, it hits the projection of the present invention, is buffered by the vegetation left uncut between the projections, and its momentum is attenuated. The recoil is buffered by the vegetation left uncut between the projections, and the effect of damping the rebounding momentum is obtained.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a blade protector of a mower according to an embodiment of the present invention.

As shown in the exploded side view of FIG. 1, a gear box 3 is connected to the lower end of the shaft frame 1 of the mower.
Is projected.

After the collar 5 and the circular saw 2 are inserted into the circular saw rotary shaft 4 one above the other, the tightening means 6 is screwed into the lower end of the circular saw rotary shaft 4 to thereby form the collar 5.
And the circular saw 2 is fixed to the circular saw rotating shaft 4.

The tightening means 6 includes a hexagon nut 7 and a washer 8
And a hub cap 9 welded to the hexagon nut 7. After the collar 5, the circular saw 2 and the seat 8 are inserted into the circular saw rotating shaft 4 in this order vertically, the hub cap 9 is formed. The collar 5 and the circular saw 2 are fixed to the circular saw rotary shaft 4 by screwing the hexagon nut 7 to the circular saw rotary shaft 4 and tightening the same.

Then, as will be described below, a cutting edge protector 10 is rotatably mounted on the tightening means 6 via a bearing 11.

That is, a bearing 11 made of, for example, a radial ball bearing is externally fitted to the hub cap 9 of the tightening means 6, and the inner peripheral edge of the cutting edge protector 10 is screwed onto the upper surface of the outer race 11a of the bearing 11. Stop at s.

The number of small screws s for fixing the cutting edge protector 10 to the bearing 11 depends on the cutting edge protector 10 and the washer 8.
Are preferably two or more in order to prevent rotation around the machine screw s.

In this case, the blade protector 10 is replaced with a small screw s.
By screwing in, the blade tip protector 10 is fixed to the tightening means 6 so that it can be disassembled from the tightening means 6.
The washer 8 is welded to the hexagon nut 7 and the inner peripheral portion of the blade protector 10 is sandwiched between the washer 8 and a nut screwed around the hub cap 9 so that the blade protector 1 is held.
0 may be fixed to the fastening means 6 so that it can be disassembled from the fastening means 6.

Further, a cylindrical collar corresponding to the outer peripheral surface of the outer race 11a of the bearing 11 is formed on the inner peripheral portion of the cutting edge protector 10, and this collar is fixedly fitted or tightly fitted to the outer race 11a of the bearing 11. The outer periphery 11a of the bearing 11 or the washer 8 fixed to the outer race 11a,
The blade protection device 10 may be fixed so as not to be disassembled from the outer race 11a by using at least two methods such as screwing and fitting.

Further, on the lower surface of the hub cap 9,
If necessary, a tool fitting hole t is formed to fit a tool for screwing the fastening means 6. In addition, in this embodiment, a radial ball bearing is used as the bearing 11 in consideration of strength, durability, ease of maintenance, price, etc. In addition, a radial roller bearing, a radial needle bearing, Commonly used as bearings, such as metal made of metal cylinders such as boron alloy, oil-impregnated metal made of porous metal cylinders impregnated with lubricating oil, and resin metal made of synthetic resin such as tetrafluoroethylene (trade name, Teflon) May be used.

In addition, as the material of the cutting edge protector 10, any material such as metal such as aluminum alloy, iron and steel including stainless steel, synthetic resin, and wood may be used, but in consideration of durability. It is recommended to use metal or synthetic resin.

As shown in the plan view of FIG. 2, the blade protection device 10 includes a disk 12 concentrically fixed to an outer race 11 a of a bearing 11, and a disk 12 from the periphery of the disk 12.
A plurality of projections 13 radially projected at an appropriate pitch P (here, 20 °) in the circumferential direction.

The disc 12 is formed to have a diameter smaller than the circular bottom of the circular saw 2 (diameter D2) so that the stems of the grass or the small tree to be cut can be inserted sufficiently deep between the blades of the circular saw 2. And also
In order to stop the rotation of the cutting edge protection device 10 by the plants around the circular saw 2, the tip of the projection 13 is projected outwardly by a dimension R including the cutting edge from the outer circumference circle (diameter D <b> 1) of the circular saw 2. is there.

As shown in the sectional view of FIG. 3 in an enlarged manner, the projecting portion 13a of the protruding portion 13 protruding outside the outer circumferential circle of the circular saw 2 is an obstacle to the circular saw 2 from the outer circumferential direction. In order to prevent the contact of the circular saw 2, the circular saw 2 is raised from the outer surface of the circular saw 2 to a position higher than the upper surface of the circular plate 12 at a position outside the gap Δ and covers the circular saw 2 from the outer periphery. Also, in order to make it difficult for pebbles and the like rolling on the ground to come into contact with the cutting edge protection device 10 and the circular saw 2, each of the vegetation entrance portions 13 is provided.
A bump-like raised portion 13b is formed on the lower surface of each protruding portion 13 over a predetermined range from the front end of a to increase the vertical distance between the ground and the disk 12 of the blade protection device 10.

In order to prevent the circular saw 2 and the disk 12 from contacting each other, an upper and lower gap δ having an appropriate size is set.
Is provided.

By the way, according to the blade protection device 10 of the mowing machine, the vegetation of the mowing field approaches the circular saw 2 through the projections 13 and is cut by the blade of the circular saw 2.

Here, the disk 12 is a circular saw rotary shaft 4 of a mower.
Is mounted so that it can rotate freely in the rotation direction of the circular saw 2 and in the opposite direction, so that the position (phase) in the rotational direction is not related to the phase of the circular saw 2. Be specific. Therefore, the projection 13 protruding around the disk 12 also faces an unspecified phase irrespective of the phase of the circular saw 2. Then, this unspecified phase is stopped by the vegetation that has entered between the vegetation receiving portions 13a of the protrusions 13.

At the time of cutting, the stem of the grass or the trunk of the small tree is cut by the blade of the circular saw 2 so as to be pressed against the projection 13, so that it can be surely cut off without being overturned.

By the way, between the vegetation of the mowing ground, the thing rolling on the ground or at least the lower part is buried underground,
Objects that are partially exposed on the ground are hidden, and among them, those whose ground height is lower than the height of the disk 12 of the cutting edge protection device 10 do not hinder mowing. On the contrary,
An object whose ground height is higher than the height of the disk 12 of the cutting edge protector 10 is obtained when the circular saw 2 is swung in an arc shape.
0 or an obstacle that comes into contact with the circular saw 2.

When one of the obstacles rolling on the ground comes into contact with the blade protector 10, the blade protector 10 pushes the obstacle to the tip side of the traverse. The speed of the circular saw 2 is high. Much lower than when you touch
Further, the operator hardly feels a reaction due to the contact.

When an obstacle rolling on the ground comes into contact with the circular saw 2, the obstacle is flipped off in the tangential direction of the outer circumferential circle of the circular saw 2, and immediately after being flipped off, the projection 13 of the blade protection device 10 is protruded. , The blade protector 10 is rotated, and the rotation of the blade protector 10 is buffered by the plants between the projections 13, especially the plants between the groves 13 a, so that the momentum is stopped or cut. The obstacle rarely flies vigorously to the outside of the cutting edge protector 10 because it drips. Also in this case, the operator hardly feels a reaction due to the contact.

When an obstacle partially buried underground comes into contact with the projection 13 of the cutting edge protection device 10 outside the circular saw 2, the circular saw 2 moves around the contact point between the obstacle and the projection 13.
And the center of the cutting edge protection device 10 moves. That is, since the circular saw 2 moves while keeping a certain distance from the obstacle, the circular saw 2 does not come into contact with the obstacle, and the circular saw 2 is flipped back by the contact. Nor.

When an obstacle partially buried underground comes into contact with the circular saw 2 through the space between the projections 13 of the cutting edge protector 10, the circular saw 2 is bounced vigorously in a tangential direction of its outer circumferential circle by reaction. However, the recoil is buffered by the trees between the projections 13 of the cutting edge protector 10 that moves together with the circular saw 2, particularly between the groves 13 a, so that the circular saw 2 and the cutting edge protector 1
The momentum of repelling 0 is reduced, and the recoil shock felt by the operator is not so large.

In short, the cutting edge of the circular saw 2 is a cutting edge protector 10
Is protected from obstacles by the protruding portion 13 of the mower and prevents direct contact between the circular saw 2 and obstacles in the mowing field, so that hard obstacles are blown off by the circular saw 2 or the circular saw 2 is flipped over obstacles. In addition, the cutting edge of the circular saw 2 is less likely to be chipped, and the recoil and shock at the time of contact with an obstacle are divided by a soft touch with a small touch, so that the grass can be cut without wiping down.

Further, since the cutting edge of the circular saw 2 is less likely to be chipped, the service life of the circular saw 2 is extended, the sharpness of the circular saw 2 does not change over a long time, and the continuous or cumulative mowing work time is reduced. Even if it becomes longer, it is not necessary to increase the rotation speed of the circular saw 2.

In the blade protector 10 of a mower according to another embodiment of the present invention shown in the plan view of FIG. 4, cutting into standing grass is facilitated, and grass and small trees with relatively thick stems are cut. The pitch P of the protrusions 13 is increased in order to make the projections possible. Also, if the pitch P of the projections 13 is increased without changing the pioneering dimension R, an obstacle can easily enter between the projections 13, but here, the dimension R of the pioneering entry 13a (the pioneering dimension) is increased. Thus, it is possible to prevent an obstacle from easily entering between the projections 13.

FIG. 5 is a sectional view of the projection 13 of this embodiment.

The other structure, operation and effect of this embodiment are the same as those of the above-described embodiment, so that detailed description is omitted here to save paper width.

In the blade protector 10 of the mower according to still another embodiment of the present invention shown in the plan view of FIG. 6, the star-shaped rotating body 14 is rotatably supported on the disk 12 between the projections 13. Let it.
The pitch P of each projection 13 and the size R of the pioneer are the same as those of the embodiment shown in FIGS. 4 and 5, and the outer circumference of each star-shaped rotating body 14 is out of the circumference of the circular saw 2. The dimension r is set to be the same as the dimension R with the pioneer of the embodiment shown in FIGS.

As shown in the sectional view of FIG. 7, the distance between the center of rotation of each star-shaped rotator 14 and the tip of the star-shaped rotator is:
In consideration of the strength problem, it is preferable that the size r of the star-shaped rotator 14 is twice or more, and in this embodiment, it is about 2.5 times (2.5r).

According to this embodiment, the movement of the circular saw 2 oscillated along the arc during the mowing operation and the cutting edge protection device 1
The rotation of 0 and the rotation of this star-shaped rotator 14 are combined,
In relation to standing grass, the same operation or effect as in the embodiment in which the pitch P of the projections 13 is large as shown in FIGS. 4 and 5 can be obtained, and obstacles such as pebbles are shown in FIGS. 1 to 3. As described above, the same operation or effect as that of the embodiment in which the pitch P of the protrusions 13 is narrow can be obtained.

Other configurations, operations and effects of this embodiment are the same as those of the above-described embodiments, and therefore, detailed description thereof will be omitted here to save paper width.

In this embodiment, one star-shaped rotator 14 is arranged between the projections 13.
Two or more star-shaped rotators 14 may be arranged between them.

Further, as the cross-sectional figure of each star-shaped rotator 14, a trapezoid shown in the cross-sectional view of FIG. 8 or a semi-oval shape shown in the cross-sectional view of FIG. 9 may be adopted.

Further, in each of the above embodiments, for example, FIG.
As shown in the plan view of FIG. 0 and the side view of FIG. 11, a roller 15 that freely rotates around the axis parallel to the rotation axis of the disk 12 around the circular saw 2 around the tip of each projection 13. Is provided, it becomes easier to divide the protrusions 13 into the ground.

[0050]

As described above, the blade protector of the mower according to the present invention is rotatably mounted on the lower side of the circular saw of the mower around the circular saw rotating shaft. Since it has a disk smaller in diameter than the diameter and a projection protruding outside the outer circumference of the circular saw at an appropriate pitch in the circumferential direction on the outer periphery of this disk, many lurks in the mowing field Obstacles are obstructed by the protrusions, making it difficult for the circular saw to come into direct contact with the circular saw.This makes it difficult for obstacles such as pebbles rolling on the ground to be blown off vigorously. It is difficult for the circular saw in contact with the obstacle protruding from inside to be bounced back vigorously, and the obstacle contacts the blade of the circular saw,
It is possible to obtain such an effect that chipping of the cutting edge hardly occurs.

Further, according to the present invention, it is difficult for an obstacle to be slammed off, so that there is less possibility that the slammed obstacle will hit an operator or a nearby person and cause injury. The effect of being enhanced is also obtained.

Further, according to the present invention, since the circular saw hardly hits an obstacle and is hardly repelled, the possibility that the repelled circular saw hits an operator or a surrounding person is reduced, and the safety is improved. The effect of being obtained is also obtained.

Further, according to the present invention, the cutting edge of the circular saw is hardly chipped, so that the sharpness of the circular saw is prevented from deteriorating for a long time. The effect that mowing can be performed with such a touch can also be obtained.

In addition, the vegetation retains the phase of the cutting edge protector of the present invention, and as a reflexive effect, the position of the vegetation with respect to the circular saw is held by the cutting edge protector, so that the vegetation does not fall down without fail. The effect of being able to prune is also obtained. In addition, according to the present invention, when the obstacle comes into contact with the circular saw from between the projections and is flipped off by the recoil, it hits the projection of the present invention, and the vegetation remaining between the projections is cut off. Has the effect of dampening its momentum, so that even if an obstacle jumps out and damages the operator or surrounding people, or damages or breaks surrounding objects, the degree of lightness is light. The effect of becoming is also obtained.

Furthermore, according to the present invention, when an obstacle repels the circular saw, the reaction of the obstacle is damped by the vegetation left uncut between the protrusions, and the rebound momentum is attenuated. Therefore, even if the operator and the surrounding people may be hurt by the rebound circular saw, the effect is reduced, the shock of the collision between the obstacle and the circular saw is small, and the mowing with a soft touch can be performed. Is also obtained.

[Brief description of the drawings]

FIG. 1 is an exploded side view of the present invention.

FIG. 2 is a plan view of the present invention.

FIG. 3 is a sectional view of a main part of the present invention.

FIG. 4 is a plan view of the present invention.

FIG. 5 is a sectional view of a main part of the present invention.

FIG. 6 is a plan view of the present invention.

FIG. 7 is a sectional view of a main part of the present invention.

FIG. 8 is a side view of a main part of the present invention.

FIG. 9 is a side view of a main part of the present invention.

FIG. 10 is a plan view of the present invention.

FIG. 11 is a side view of a main part of the present invention.

FIG. 12 is an exploded side view of a main part of a conventional mower.

[Explanation of symbols]

 2 Circular saw 4 Circular saw rotating shaft 10 Blade protection tool 12 Disk 13 Projection

[Procedure amendment]

[Submission date] December 16, 1999 (1999.12.
16)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

The number of small screws s for fixing the blade protector 10 to the bearing 11 depends on whether the blade protector 10 is a small screw s.
It is preferable that the number is two or more in order to prevent rotation around the center.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0022

[Correction method] Change

[Correction contents]

In this case, the blade protector 10 is replaced with a small screw s.
The cutting edge protector 10 by screwing
It is fixed so that it can be disassembled from race 11, but
Then, the bearing 11 is provided on the inner peripheral portion of the blade tip protector 10.
A cylindrical collar corresponding to the outer peripheral surface of the outer race 11a
And this collar is attached to the outer surface of the bearing 11.
Close fit or tight fit over race 11a
And bonded to the outer race 11a of the bearing 11
Or bonding, screwing, mating, etc.
To remove the edge protector 10 from the outer race 11a.
May be fixed so that they cannot be easily disassembled.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0023

[Correction method] Deleted

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction contents]

In the blade protector 10 of the mower according to still another embodiment of the present invention shown in the plan view of FIG. 6, the star-shaped rotating body 14 is rotatably supported on the disk 12 between the projections 13. Let it.
The pitch P of each projection 13 and the size R of the pioneer are the same as those of the embodiment shown in FIGS. 4 and 5, and the outer circumference of each star-shaped rotating body 14 is out of the circumference of the circular saw 2. The dimension r is set to be the same as the dimension R with pioneer of the embodiment shown in FIGS .

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0045

[Correction method] Change

[Correction contents]

According to this embodiment, the movement of the circular saw 2 oscillated along the arc during the mowing operation and the cutting edge protection device 1
The rotation of 0 and the rotation of this star-shaped rotator 14 are combined,
In relation to standing grass, the same action or effect as in the embodiment in which the pitch P of the projections 13 is large as shown in FIGS. 4 and 5 can be obtained, and for obstacles such as pebbles, FIGS.
As shown in FIG. 2 , the same operation or effect as in the embodiment in which the pitch P of the projections 13 is narrow can be obtained.

Claims (1)

[Claims] 1. A circular disk having a diameter smaller than the circular bottom of the circular saw, which is rotatably mounted on the lower side of the circular saw of the mower. And a protrusion protruding outside the outer circumference of the circular saw at an appropriate pitch in the direction.