JP4573245B2 - Tangle prevention structure in mower - Google Patents

Description

A mowing machine that attaches a cutting blade to a rotating shaft that protrudes from the main body that is fixed to the tip of the support rod, and cuts weeds by rotating the cutting blade. It is invention which concerns on the entanglement prevention structure to do.

In order to cut weeds, a mower that performs cutting work with a cutting blade that rotates at high speed is widely used. In this seed mower, foreign matter such as cut grass or dust in the work area is entangled with the rotating shaft, causing a situation that hinders work. Means for preventing entanglement have been devised to cope with such a situation.
In Patent Document 1, a rotary shaft protection member is attached to a rotary shaft, and a blade is formed on a part of the rotary shaft protection member, thereby cutting cut grass or the like that tries to enter the rotary shaft portion. The idea of preventing entanglement is disclosed. In Patent Document 2, the idea of providing a flange-type entanglement preventing member to prevent foreign matter from entering the rotating shaft portion of the blade plate is disclosed in Patent Document 3, and vine grass or the like does not wind around the rotating shaft. As described above, a concept is disclosed in which a triangular plate-like member is disposed between the support rod and the cutting blade surface so as to be close to the cutting surface, and the rotation of the cutting blade prevents the suspension from rotating around the rotation shaft. Yes.
Japanese Patent Laid-Open No. 11-18543 Japanese Patent Laid-Open No. 11-168939 Japanese Patent Publication No. 2001-103824

With the idea of cutting what is entangled by a cutting blade as disclosed in Patent Document 1, entanglement cannot be prevented if the cutting blade (blade part) is not cut. In addition, it is impossible to prevent foreign matter or cut grass that has entered inside the cutting blade from being entangled with the rotating shaft, and the structure itself is complicated, so that the cutting blade is dangerous for the operator.
As disclosed in Patent Documents 2 and 3, in the structure that excludes the foreign matter reaching the rotating shaft, the gap between the fixed entanglement preventing member and the rotating blade plate cannot be completely eliminated. There is a drawback that it may intrude and cannot always effectively prevent entanglement.
In view of the above-described drawbacks of the prior art, the present invention is intended to realize a structure that can prevent grass cut by a simpler structure from being entangled with a rotating shaft.

In order to achieve the above object, a mower embodying the present invention protrudes from a main body 1 fixed to the tip of a support rod 2 and is cut at a tip of a rotary shaft 3 driven by a power source such as a motor. And cutting weeds by rotating the cutting blade 4.
In the above mower, a tapered skirt portion 6 having a diameter expanded upward and rotating together with the rotary shaft 3 is disposed between the cutting blade 4 attached to the rotary shaft 3 and the main body 1. At this time, the upper end of the skirt portion 5 is expanded outwardly from the outer periphery of the lower end 1a of the main body 1. Thereby, foreign matter such as grass that has been cut off is blown off at the skirt portion 6 that rotates together with the rotating shaft.

The skirt portion 6 is formed on a mounting base 5 that is integrally molded with a synthetic resin material and fixed to the tip of the rotary shaft 3. That is, the mounting base 5 is cylindrical, and its upper end is formed into a substantially V-shaped cross section with the inner cylinder 5a and the skirt 6 that expands outwardly, and the cutting blade 4 is attached to the tip.
The lower end 1a of the main body 1 is positioned in a space having a substantially V-shaped cross section formed at the upper end portion of the mounting base 5, and the lower end 1a of the main body 1 is surrounded by the upper end of the skirt portion 6 whose diameter is increased upward.

  According to the entanglement preventing structure in the mower of the present invention as set forth in claim 1, the skirt that rotates together with the rotary shaft 3 when the grass or foreign matter cut by the cutting blade 4 scatters from below or obliquely downward toward the center of rotation. Collide with part 6. At this time, since the skirt portion 6 is an inclined surface and rotates at a high speed, the foreign matter colliding with the skirt portion 6 from below is blown outward. Therefore, it is possible to effectively prevent the foreign matter from being entangled with the rotating shaft.

And in this invention, since the skirt part 6 is formed in the mounting base 5 for mounting | wearing with the cutting blade 4 integrally molded with the synthetic resin material fixed to the front-end | tip of the rotating shaft 3, a structure can be simplified. . More specifically, the upper end portion of the cylindrical mounting base 5 is formed integrally with the inner cylinder 5a and the skirt portion 6 whose diameter is increased outwardly so as to have a substantially V-shaped cross section. 4 is installed.

Further, by positioning the lower end 1a of the main body 1 in a space having a substantially V-shaped cross section formed at the upper end portion of the mounting base 5, it is possible to more reliably prevent foreign matter such as cut grass from entering the rotary shaft portion. Can be prevented. Even if a foreign object becomes entangled with the upper end of the mounting base 5, it is a large-diameter inner cylinder 5a portion that rotates in the same manner as the cutting blade 4, and weeds are rarely entangled. it can.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a tangling prevention structure for a mower according to the present invention will be described below with reference to the accompanying drawings.
1 is an exploded perspective view of the tip portion of the mower, FIG. 2 is a longitudinal sectional view of only the tip portion of the mower, FIG. 3 is a plan view of the tip portion of the mower, and FIG. 4 is a bottom surface of the tip portion of the mower. FIG. 5 is an enlarged view of a portion of the tip of the mower, and FIG. 6 is a side view of the entire mower.

  The mowing machine of the illustrated embodiment has the main body 1 fixed to the tip of the support rod 2, the handle 7 fixed to the base end of the support rod 2 is gripped, and the mowing blade 4 mounted on the main body 1 rotates at high speed to provide weeds. It is a relatively simple mower that performs the cutting operation of the workpiece A such as the above. The handle 7 is provided with a switch 8, a lock button 9, and a battery (not shown) that can be operated with a grasped finger.

  A motor 10 is built in the main body 1, an output shaft of the motor 10 is a rotating shaft 3, and a mounting base 5 for a cutting blade 4 is fixed to the rotating shaft 3. Therefore, the rotating shaft 3 is rotated by the motor 10, and the cutting operation such as weeds can be advanced by the cutting blade 4 attached to the mounting base 5 fixed to the rotating shaft 3. At this time, a skirt portion 6 is formed on the upper end of the mounting base 5 to prevent foreign matter such as cut weeds from getting tangled. A guard plate 11 that covers the upper portion of the cutting blade 4 is fixed to the lower half of the lower end of the main body 1, and an annular guard ring 12 is detachably mounted on the upper surface of the guard plate 11.

As shown in FIGS. 3 and 4, the guard plate 11 fixed to the main body 1 has a fan shape that covers only the rear portion, and prevents the pebbles blown off by the cutting blade 4 from hitting the operator. On the other hand, the guard ring 12 mounted on the upper surface of the guard plate 11 is located outside the rotation locus of the cutting blade 4 so that obstacles other than the cut object such as flexible weeds collide with the cutting blade 4. It is to prevent. In other words, it functions as a safety guard that prevents a nearby person from being injured by mistake or preventing the cutting blade 4 from hitting the cutting blade 4.

  As shown in FIGS. 1 and 2, the fan-shaped guard plate 11 fits the inner peripheral portion of the guard plate 11 in the fitting groove 13 formed in the rear half circumference of the main body 1, and The formed claw 14 is made detachable by engaging with a part of the main body 1. The holding means for the guard ring 12 is provided at a plurality of positions on the upper surface of the guard plate 11 along the arcuate locus. That is, the holding part 16 having the groove 15 into which the guard ring is fitted and the support plates 17 and 17 for supporting the guard ring 12 from below are arranged on the sector-shaped guard plate 11. Then, as the guard ring 12, a synthetic resin tube material having a certain size of flexibility is used, and both ends are fitted and held in the grooves 15 of the holding portion 16, respectively, and the two positions at the intermediate position are supported by the support plate 17. It is supported by.

  A mounting base 5 of a cutting blade 4 mounted on a rotary shaft 3 (in the illustrated embodiment, a motor output shaft) driven by a motor 10 accommodated in the main body 1 is a cylinder whose lower end is closed using a synthetic resin material. The skirt part 6 which is molded in a shape and expands upward at the upper end part is formed. More specifically, the upper end portion of the cylinder is the inner cylinder 5a, and the skirt portion 6 that extends outward is integrally formed, so that the cross-sectional shape of the portion is substantially V-shaped. The outer diameter of the skirt portion 6 is formed to be slightly larger than the outer diameter of the lower end 1a of the main body 1, and a recess 1b having a diameter into which the inner cylinder 5a of the mounting base 5 enters is formed on the lower end surface of the main body 1. Therefore, by fixing the mounting base 5 to the rotary shaft 3, the inner cylinder 5a of the mounting base 5 enters the recess 1b, and the lower end 1a of the main body 1 formed slightly tapered is formed by the inner cylinder 5a and the skirt portion 6. Will be located in a V-shaped space.

The skirt portion 6 formed on the mounting base 5 of the cutting blade 4 does not have to be very large, and only slightly covers the lower end portion of the main body 1. In the illustrated embodiment, the skirt portion 6 has an inclination angle. 45 degrees through you are about 60 degrees.

In the illustrated mower, the cutting blade 4 is formed in a propeller shape. The propeller-shaped cutting blade 4 is molded from a flexible synthetic resin material such as nylon resin, and can be detachably mounted on the mounting base 5.
That is, the cutting blade 4 has a flat plate shape, the center being a wide width portion 4a, the left and right sides being narrow width portions 4b, the left and right edges of the narrow width portion 4b being sharp blade portions 4c, and a long hole in the wide width portion 4a. 4d is drilled. On the other hand, on the end surface of the cylindrical mounting base 5 on which the cutting blade 4 is mounted, a recess 18 having a shape into which a part of the wide portion 4a and the narrow portion 4b of the cutting blade are fitted is formed as shown in FIG. In order to prevent the cutting blade 4 arranged in the recess 18 from being released outwardly at the open end portion of the recess 18, the locking claws 19 protrude from both the left and right sides of the open end, and the cutting blade 4 is inserted into the groove 15. An engaging protrusion 20 that engages with the elongated hole 4d is projected.

In order to mount the cutting blade 4 configured as described above in the recess 18 of the mounting base 5, as shown by the dotted line in FIG. 2, the cutting blade 4 is largely bent with fingers, and the cutting blade is inserted into the recess 18 on the end face of the mounting base 5. 4 wide part 4a is inserted. That is, by bending the cutting blade 4, the wide width portion 4a is inserted from the narrow width portion 4b to the lower side of the locking claw 19, and the bending by the finger is released at a predetermined position of the mounting. Thus, the cutting blade 4 can be fitted into the recess 18 formed in the shape of the central portion of the cutting blade without being easily dropped. At this time, the locking projection 20 formed in the recess 18 is engaged with the elongated hole 4d of the cutting blade 4 to reliably prevent the cutting blade 4 from moving in the longitudinal direction.
The cutting blade 4 can be made disposable by using a synthetic resin, and can be used by inverting one cutting blade by forming the blade portions 4c on the left and right sides of the narrow width portion 4b.

When weeds and the like are cut by the mower having the structure described above, the grass cut by the cutting blade 4 is scattered upward and outward by the centrifugal force of the cutting blade 4 . At this time, the grass scattered in the upper center direction collides with the skirt portion 6. As shown in FIG. 5, the grass that has collided with the skirt portion 6 from obliquely below is effectively blown outward by the centrifugal force of the skirt portion 6. Direction of sprung skirt portion 6 is related to the inclination angle of the skirt portion 6, according to the experiments of the present inventors, to 45 degrees to as the illustrated embodiment the inclination angle of the skirt portion slope of about 60 degrees It was most effective when used as a horn.

In other words, the skirt portion 6 by the fact that an inclined surface, together with the cutting blade 4 is to a high speed, which can effectively eliminate the grass clippings, above, for example cutting blades 4 In the case where a horizontal flange member is arranged in a fixed state, the blown-off foreign matter may rebound even if it is directed downward or inward, and effectively removes the foreign matter that has entered. Is not possible.

FIG. 1 is an exploded perspective view of a tip portion of a mower, 2 is a longitudinal sectional view of only the tip portion of the mower, FIG. 3 is a plan view of the tip portion of the mower, FIG. 4 is a bottom view of the tip portion of the mower, FIG. 5 is an enlarged view of a portion of the tip of the mower, FIG. 6 is a side view of the entire mower.

DESCRIPTION OF SYMBOLS 1 ... Main body, 1a ... Lower end, 1b ... Recess, 2 ... Support rod, 3 ... Rotating shaft, 4 ... Cutting blade, 4a ... Wide part, 4b ... Narrow part, 4c ... Blade part, 4d ... Long hole, 5 ... Mounting base, 5a ... Inner cylinder, 6 ... Skirt, 7 ... Handle, 8 ... Switch, 9 ... Lock button, 10 ... Motor, 11 ... Guard plate, 12 ... Guard ring, 13 ... Fitting groove, 14 ... Nail 15 ... Groove, 16 ... Holding part, 17 ... Support plate, 18 ... Recess, 19 ... Locking claw, 20 ... Locking protrusion.

Claims (1)

In a mower that protrudes from the main body fixed to the tip of the support rod, attaches a cutting blade to the tip of a rotating shaft that is driven to rotate by a power source such as a motor, and cuts weeds by rotating the cutting blade.
A cylindrical shape integrally molded with a synthetic resin material at the tip of the rotating shaft, and the upper end thereof is formed into a substantially V-shaped cross section with an inner cylinder and a skirt that expands outwardly, and a cutting blade is formed at the tip Secure the mounting base to be installed.
The entanglement in the mower characterized in that the lower end of the main body is positioned in a space having a substantially V-shaped cross section formed on the mounting base, and the outer periphery of the lower end of the main body is surrounded by the upper end of the skirt that expands upward. Prevention structure.

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