JPS5915864Y2 - Dust-proof structure for brush cutters - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure for preventing grass, dirt, etc. from entering the bearing portion of the lower gear case of a brush cutter.

Conventionally, various anti-wrapping devices have been proposed and implemented for brush cutters, but their structures are complex, and although they are useful for preventing long grass, leaves, etc. from wrapping around, they are not practical. Small pieces of stems cut by the cutting blade, dirt, etc. often enter through the small gap between the bearing and the upper flange during long-term use, thereby damaging the bearing.

Therefore, in order to solve these problems, the present invention provides a brush cutter in which a vertical rotating shaft is rotatably inserted into a fixed gear case, and a cutting blade is fixed to the lower end of the rotating shaft. The upper flange, which is the member to which the cutter blade is attached, or the ring body attached to the outer periphery of the upper flange, is fixed to the outer periphery of the gear case while maintaining a narrow gap in the step formed on the outer periphery of the gear case. and the gear case is fitted with a diameter substantially equal to the outermost circumference of the gear case, and the upper flange or the upper end of the ring body is provided with concavities and convexities alternately and continuously formed in a range slightly shorter than the length of the step part. It provides structure.

A specific example of the present invention will be described below with reference to the drawings. 1 is a transmission shaft driven by a prime mover (not shown), 2 is a main rod in which the transmission shaft 1 is installed, 3 is a gear case fixed to the main rod 2, 4 is a joint that connects the transmission shaft 2 and the driving bevel gear 5; 6 is a passive bevel gear that meshes with the driving bevel gear 5; 7 is a rotating shaft; the passive bevel gear 6 is fixed to the upper part with a key 8; and the lower part is a rotating shaft. is a spline 9, and a screw 10 is formed on its end side 11.1
1', 12° and 13 are respective bearings.

Reference numeral 14 denotes an upper flange fixed to the spline 9, and its outer diameter is approximately the same as that of the outermost cylindrical portion of the gear case 3.

On the other hand, a stepped portion is formed on the outer periphery of the gear case 3, and the upper flange 14 is inserted into the stepped portion while maintaining a gap at both the diameter and end portions of the stepped portion. Make it fit.

The diameters of the upper flange 14 and the outermost circumference of the gear case 3 are made approximately equal.

In addition, in the figure, a ring body 14' is provided on the outer periphery of the upper flange 14.
is shown in which the outer periphery of the ring body 14' is fitted into the step, but of course the upper flange 14 and the ring body 14' may have an integral structure. good.

Reference numeral 16 denotes a cutting blade which is clamped and fixed to the rotary shaft 7 via a lower flange 17, a mounting plate 18, and the like with annular screws 19 and 19'.

Incidentally, this invention further comprises continuously and alternately forming unevenness on the upper end of the upper flange 14 or the ring body 14' in a range slightly shorter than the length of the stepped portion.

Therefore, this uneven portion is formed by forming recesses adjacent to the protruding pieces 15 alternately along the circumference, and means that the depth of the recesses is slightly shorter than the length of the stepped portion.

Next, the operation will be explained. As is well known, the brush cutter equipped with the present invention performs reaping work by rotating the mower blade 16 through the transmission shaft 1 to cut the grass.

At this time, the cut long grass, leaves, etc. fall down on the spot, and small pieces are scattered by the rotating cutting blade 16 and try to enter the gap between the gear case 3 and the upper flange 14, but the rotating blade upper flange 14 or ring body 14'
It hits the outer peripheral protrusion piece 15 and is thrown away.

Also, the minute dust generated during reaping is removed from the upper flange 14.
, or an uneven portion formed on the outer periphery of the ring body 14',
That is, it prevents the projecting piece 15 and the recess from being blown away by the wind generated by the recess and entering the inside.

In other words, if the outer periphery of the upper flange 14 or the ring body 14' is flat and has no irregularities, wind will not be generated and the pedicle pieces will not be blown away. This skillfully prevents the intrusion of stem fragments and dust.

Furthermore, since this unevenness is slightly shorter than the length of the step, the recesses (holes) adjacent to the protruding pieces 15 are relatively long, and have the effect of throwing out stem pieces and debris that have entered. There is.

In other words, when the upper flange 14 or the ring body 14' rotates, the stem pieces and debris that have entered the inside of the upper flange 14 or the ring body 14' rotate.
Since it comes into contact with the inner periphery of ' due to centrifugal force, centrifugal force acts on it, and it is directly emitted to the outside from this recess (hole).

The present invention has excellent effects as described above, and furthermore, the structure can be simplified and it can be manufactured at low cost.

[Brief explanation of the drawing]

The drawings show a dustproof device for a brush cutter according to the present invention, with FIG. 1 being a cross-sectional view of the main parts, and FIG. 2 being a perspective view. Code, 3... Gear case, 7... Rotating shaft, 14... Upper flange, 14'...
...Ring body, 16...Mowing blade.

Claims (1)

[Scope of utility model registration request] In a brush cutter in which a vertical rotating shaft is rotatably inserted into a fixed gear case and a cutting blade is fixed to the lower end of the rotating shaft, a member that is fixed to the rotating shaft and to which the cutting blade is attached. The upper flange of the barrel or the ring body attached to the outer periphery of the upper flange is fitted into the step formed on the outer periphery of the gear case while maintaining a gap and having a diameter approximately equal to the outermost periphery of the gear case. Further, a dust-proof structure for an interest paying machine is provided, in which unevenness is continuously and alternately formed on the upper flange or the upper end of the ring body in a range slightly shorter than the length of the stepped portion.