JPH0214340Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a reinforcing device for preventing bending and deformation of an outer pipe in a brush cutter.

``Prior Art'' In general, a brush cutter, particularly a weed cutter, starts a prime mover 4 to rotationally drive a cutting blade 1 through a shaft in an outer pipe 3, as shown in FIG.
Weeds are cut by holding the handle 5 and swinging the cutting blade 1.

``Problem to be solved by the invention'' As shown in Fig. 8, in the conventional brush cutter, when the cutting blade 1 hits the tree trunk 2 while cutting weeds, the rotational force of the cutting blade 1 causes the tree trunk 2 to cut into the space between the cutting blade 1 and the outer pipe 3, and as a result, a force in the direction of arrow A was applied to the vicinity of the tip of the outer pipe 3, causing the tip of the outer pipe 3 to be unintentionally bent and deformed. In particular, over many years of use, the tip of the outer pipe 3 gradually gets damaged and the strength of the tip of the outer pipe 3 decreases, so when force is applied to the tip of the outer pipe 3 as described above, it tends to bend and deform. Another drawback was that the vibrations were large and had a negative effect on the body of the worker. In order to prevent this bending and deformation, it is conceivable to perform hard alumite treatment on the surface of the aluminum outer pipe 3, but this hard alumite treatment is extremely expensive and leads to an increase in the cost of the brush cutter. Even if only the surface of the tip of the outer pipe 3 is treated with hard alumite and the other parts are treated with normal alumite, it is very time-consuming to apply hard alumite treatment to only a part of the outer pipe 3, and it is rather difficult to do so. There were various problems that led to high costs.

Therefore, in view of the above circumstances, the present invention is capable of reinforcing the tip of the outer pipe with an extremely simple structure and at low cost, and also by applying ordinary alumite treatment that can be performed at low cost to parts other than the tip of the outer pipe, especially the outer pipe. To provide a reinforcing device for an outer pipe in a brush cutter that is easy to use and does not cause a rise in cost.

``Means for Solving the Problems'' The present invention has been made to achieve the above-mentioned object. When fitting a reinforcing pipe of the length necessary to provide protection and reinforcement beyond the outer diameter position, and attaching a protective cover to the outer pipe to cover the cutting blade in the lower part of the outer pipe, insert the reinforcing pipe into the outer pipe. This invention is characterized by a reinforcing device for an outer pipe in a brush cutter, in which a protective cover attachment part is attached to the tip of the outer pipe by sandwiching the outer pipe.

``Operation'' The reinforcing device for the outer pipe of the brush cutter of the present invention is such that when the cutting blade inadvertently hits the trunk of a tree while cutting weeds, the rotational force of the cutting blade causes the trunk of the tree to Even if the tree trunk, etc. tries to bite between the cutting blade and the outer pipe, the protective cover first separates the tree trunk from the cutting blade, and the rotational force of the cutting blade prevents the tree trunk, etc. from entering between the cutting blade and the outer pipe. This prevents digging, reduces the impact force of tree trunks, etc. on the outer pipe, and prevents the tree trunks, etc. from colliding directly with the outer pipe, instead colliding with the reinforcing pipe, so that the outer pipe It is designed to prevent damage to the

"Embodiment" Hereinafter, an embodiment of the reinforcing device for an outer pipe in a brush cutter according to the present invention will be described. In Fig. 1, 11 is a prime mover, 12 is an outer pipe, and 13 is an outer pipe.
1 is a handle, 14 is a gear case, and 15 is a cutting blade. A reinforcing pipe 16 of a predetermined length is attached to the tip of the outer pipe 12.

The reinforcing pipe 16 may be attached in various ways, and at least the reinforcing pipe 16 is designed to prevent free sliding between the distal end and the proximal end of the outer pipe 12.
Further, the reinforcing pipe 16 is usually made of aluminum, and a material thinner than the outer pipe 12 can sufficiently serve the purpose, and a hard synthetic resin can also be used.

First, FIG. 2 shows one type of this, in which the outer pipe 1 is attached to the rear end side of the attachment part 14a of the gear case 14
A reinforcing pipe 16a is fixed near the tip of the pipe 2 with adhesive.

3 and 4 show that the reinforcing pipe 16b is deformed into a slightly oval shape rather than a perfect circle.
b is press-fitted near the tip of the perfectly circular outer pipe 12, and this press-fitting changes the reinforcing pipe 16b into a perfect circle or a nearly perfect circle according to the shape of the outer pipe 12, and the restoring force at that time causes the reinforcing pipe 16b to change to the outer pipe 12. It is becoming fixed.

FIGS. 5 and 6 show that when the attachment part 14a with the split groove 17 of the gear case is attached to the tip of the outer pipe 12 by fastening with a bolt 18 or the like, the attachment part 14a and the outer pipe 12 are interposed. A tightening protection part 19 is formed at one end of the reinforcing pipe 16c, so that when the gear case 14 is attached to the outer pipe 12, the reinforcing pipe 16c is also fixed. The reinforcing pipe 16c has a split groove 20 formed on one side that is clamped by the mounting part 14a, and the split groove 20 becomes a width clamp when clamped by the mounting part 14a, and clamps the outer surface of the outer pipe 12. It is designed to be fixed in place.

FIG. 7 shows the most effective form of the present invention, in which one side of the reinforcing pipe 16d is connected to a tightening protection part 22 in which a split groove 21 is formed, similar to the reinforcing pipe 16c in FIG. Then, the reinforcing pipe 16d is inserted into the tip of the outer pipe 12, the tightening protection part 22 is located on the rear end side of the mounting part 14a, and the protective cover 23 having a substantially L-shaped cross section is attached to the tightening protection part 22. At the same time, the reinforcing pipe 16d is also fixed to the outer pipe 12. In other words, the mounting portion 24 of the protective cover 23 consists of a U-shaped mounting bracket 24a and a U-shaped mounting pusher 24b.
A bolt 25 is inserted between the outward flanges 24c and 24d provided on both sides of the mounting bracket 24a and the mounting pusher 24b.
and nuts 26, and at this time the mounting portion 24
The tightening protection portion 22 of the reinforcing pipe 16d is interposed between the reinforcing pipe 16d and the outer pipe 12 to tighten the reinforcing pipe 16d. The protective cover 23 is attached to the mounting bracket 24a via a bracket 27 above the front side of the cutting blade 25.
It is adapted to be attached so as to cover approximately half the area of the cutting blade 25 on the lower side of the outer pipe 12.

The tightening protection parts 19 and 22 are the outer pipe 12
For fixing the reinforcing pipes 16c and 16d,
Mounting part 14a or mounting part 2 of gear case 14
This protects the outer pipe 12 from being scratched when attaching the outer pipe 4 to the outer pipe 12.

In each of the above-mentioned embodiments, if the color of the reinforcing pipe 16 is changed from that of the outer pipe 12, the brush cutter can be accented and the design is good. In addition, Fig. 2, Fig. 4, Fig. 5, Fig. 7
In the figure, 28 is a shaft.

"Effects of the invention" As described above, according to the reinforcing device for the outer pipe of the brush cutter according to the present invention, the tip of the outer pipe can be reinforced with an extremely simple structure, and therefore, unlike conventional methods, the cutting blade hits a tree trunk, etc.,
Due to the rotational force of the cutting blade, tree trunks, etc. get wedged between the cutting blade and the outer pipe, and as a result, a large force is applied to the area near the tip of the outer pipe, causing the area near the tip of the outer pipe to bend unexpectedly. can be prevented. In other words, a tree trunk, etc. hits the cutting blade and feeds the tree trunk, etc. in the direction of rotation of the cutting blade, but before the tree trunk, etc. bites between the cutting blade and the outer pipe, the protective cover protects against the cutting blade. By separating the bite of the tree trunk, etc., it prevents the tree trunk, etc. from biting between the cutting blade and the outer pipe, and further reduces the impact force on the outer pipe, thereby preventing large impact force from being applied to the outer pipe. In addition, damage to the outer pipe can be prevented since the tree trunk or the like only collides with the reinforcing pipe due to the impact force, and is prevented from directly colliding with the outer pipe. In particular, if a reinforcing pipe is simply fitted to the outer pipe, when tree roots, etc. are caught between the cutting blade and the outer pipe, the rotational force of the cutting blade will cause the tree roots, etc. to exert a tremendous force on the outer pipe. It can effectively eliminate what is said to be unavoidable. Moreover, since the attachment part to which the protective cover is attached is used to attach the reinforcing pipe to the outer pipe, the reinforcing pipe functions as a seat for the attachment part, compared to attaching the attachment part directly to the outer pipe. When installing the protective cover mounting part, which is frequently replaced,
As the number of replacements increases, damage to the outer pipe can be prevented, and furthermore, ordinary alumite treatment can be applied at low cost to the entire outer pipe or to parts other than the tip of the outer pipe where the reinforcing pipe is attached. It is extremely convenient in practical terms and has never been associated with a rise in costs.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a brush cutter equipped with a reinforcing device on the outer pipe according to the present invention, Fig. 2 is a cross-sectional view of essential parts of the brush cutter showing the reinforcing device of the first embodiment, and Fig. 3 is a second embodiment. A side view of the reinforcing device showing the
Fig. 5 is a sectional view of the main part of a brush cutter showing the reinforcing device according to the third embodiment, and Fig. 6 is an end view of the main part of the reinforcing device shown in the figure attached to the outer pipe. FIG. 7 is a sectional view of a main part of a brush cutter showing a reinforcing device according to a fourth preferred embodiment of the present invention; FIG. 8 is a plane view for explaining the drawbacks of a conventional brush cutter. It is a diagram. DESCRIPTION OF SYMBOLS 11... Prime mover, 12... Outer pipe, 13... Handle, 14... Gear case, 14a... Mounting part, 1
5... Cutting blade, 16d... Reinforcement pipe, 18, 25... Bolt, 22... Tightening protection part, 23... Protective cover, 2
4... Mounting portion, 24a... Mounting bracket, 24b... Mounting pusher, 24c, 24d... Outward flange, 26... Nut, 27... Bracket, 28... Shaft.

Claims (1)

[Scope of utility model registration request] In a brush cutter, a reinforcing pipe of the length necessary to protect and reinforce the cutting blade beyond the outer diameter position is fitted to the tip side of the outer pipe to which the cutting blade is pivoted via the gear case. , a brush cutter characterized in that, when attaching a protective cover to the outer pipe to cover the cutting blade in the lower part of the outer pipe, a mounting part of the protective cover is attached to the tip of the outer pipe by sandwiching the reinforcing pipe. reinforcing device for the outer pipe.