JPH0711113U - Anti-vibration mechanism in brush cutter - Google Patents

Abstract

(57) [Summary] [Purpose] The objective is to obtain an improved anti-vibration mechanism for a brush cutter. [Structure] A cushioning material such as rubber is installed inside the clutch case in advance, and a rotation stopping hole is opened at a predetermined position, while a flange is provided around one end of a cylindrical holder made of synthetic resin. At the same time, the other end is provided with a flexible engagement to be fitted in the rotation stopping hole, and the drive shaft pipe is forcibly press-fitted and held in the cylindrical holder.
This anti-vibration mechanism has a simple structure and can be easily assembled.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a vibration isolation mechanism of a brush cutter.

[0002]

[Problems to be solved by conventional techniques and devices]

 Conventionally, a handheld brush cutter configured to transmit the rotational force of the engine installed in the brush cutter main body to the brush blade at the tip of the brush mechanism through the clutch mechanism and drive shaft is an efficient brush cutter. It is widely used because it can perform work.

Incidentally, in this type of brush cutter, if the vibration generated by the engine is transmitted to the grip handle or the like through the drive shaft pipe, not only the operator is fatigued but also the structure is unfavorable. It is devised to buffer.

In order to absorb such vibrations, conventionally, as shown in FIG. 4, rubber or the like is damped on the outside of the alloy holder 3 holding the drive shaft pipe 1 by means such as baking or bonding. An anti-vibration mechanism in which the cushioning material 5 is fixed and the cushioning material 5 is sandwiched between the bearing holder 7 and the clutch case 9 or the cushioning material 5 is assembled inside the clutch case 9 as shown in FIG. An anti-vibration mechanism is used in which the clutch case 9 and the drive shaft pipe 1 are directly fixed by a set screw 11 that also serves as a rotation stop.

However, the former mechanism requires the work of separately manufacturing the cushioning material and the holder and then fixing them by baking or gluing, so that there is a problem in that the number of manufacturing steps is large and the cost is high. Although the mechanism of (3) is simple in structure, not only does it require threaded hole machining that requires high precision at the prescribed locations of the clutch case and drive shaft pipe, but the drive shaft pipe is forcibly mounted on the cushioning material installed inside the clutch case. Work to insert the screw holes and align the screw holes is complicated.Furthermore, if oil etc. adheres between the cushioning material and the drive shaft pipe, the screw hole parts will wear and rattling will occur. Various problems to be solved were pointed out.

[0006]

[Means for solving the problem]

 Therefore, in this invention, a cushioning material such as rubber is preliminarily assembled and arranged inside the clutch case, and a rotation stopping hole is formed at a predetermined position, while a flange is formed at one end of a cylindrical holder made of synthetic resin. And a flexible engaging portion that fits in the rotation-stopping hole portion is provided on the other end side, and the drive shaft pipe is forcibly press-fitted and held in the cylindrical holder. By adopting the anti-vibration mechanism, not only the structure but also the assembling is intended to be facilitated.

In this case, parallel split grooves are formed along the longitudinal direction of the middle portion of the cylindrical holder, and the tip of these split grooves is provided with a convex portion that bulges outward in the radial direction of the holder. If this convex portion is configured as a flexible engaging portion, the tubular holder can be manufactured extremely easily.

[0008]

[Work]

 In the vibration damping mechanism according to the present invention, the vibration generated in the engine is preferably damped by the shock absorbing material inside the clutch case.

[0009]

【Example】

 Next, an embodiment of the anti-vibration mechanism in the brush cutter according to the present invention will be described in detail below with reference to the accompanying drawings.

1 and 2, the vibration damping mechanism 20 according to the present invention is configured such that a tubular holder 26 is attached and fixed to a cushioning material 24 that is pre-assembled and arranged inside the clutch case 22. The drive shaft pipe 28 is forcibly press-fitted, and the drive shaft pipe 28 is tightened with a tightening bolt 30 provided in the cylindrical holder 26.

That is, a boss 36 is integrally provided at the center of the clutch drum 34 of the centrifugal clutch 32 connected to the output shaft (not shown) of the engine, and the boss 36 is provided via a bearing 38 to the clutch 38. It is held in the case 22. On the other hand, detent holes 40, 40 are formed at predetermined positions of the cushioning material 24 arranged inside the clutch case 22 with the central axis O interposed therebetween. Further, a flange 42 is provided around one end of the synthetic resin cylindrical holder 26, and a flexible engaging portion 44 that fits into each of the rotation stopping holes 40 is formed on the other end. Suru

As shown in FIG. 3, each flexible engaging portion 44 forms split grooves 46, 46 parallel to each other along the longitudinal direction of the middle portion of the cylindrical holder 26, and these split grooves are formed. It is constituted by a convex portion 44a that bulges outward in the radial direction of the cylindrical holder 26 at the tip end portions of 46 and 46. When the tubular holder 26 configured as described above is attached to the cushioning material 24, the flexible engaging portion 44 (the convex portion 44a) bends as shown by the broken line in FIG. It can be performed easily, and if the flexible engagement portion 44 (projection portion 44a) is fitted into the rotation stopping hole portion 40, the tubular holder 26 and the cushioning material 24 can be suitably integrated. It will be appreciated that you can do it.

In the brush cutter provided with the vibration isolating mechanism 20 according to the present invention configured as described above, the vibration generated by the engine is a synthetic resin having a cushioning function as the cushioning material 24 inside the clutch case 22 and the material itself. Since it is suitably buffered by the cylindrical holder 26 made of, it is possible to suppress the vibration transmitted to the operator through the grip handle attached to the drive shaft pipe 28 as much as possible.

[0014]

[Effect of device]

 As described above, according to the vibration isolating mechanism of the present invention, the structure is simple and not only the assembly but also the replacement work can be performed very easily. In addition, the clutch case, cushioning material, and tubular holder can be easily molded, and since screw hole machining is not required, the number of manufacturing processes can be reduced and cost can be reduced. It has various advantages such as the ability to securely fix the material and prevent it from turning and pulling out, and its practical effect is extremely large.

The preferred embodiment of the anti-vibration mechanism in the brush cutter according to the present invention has been described above. However, the present invention is not limited to this embodiment. For example, a fan cover and a clutch case are integrated. It is needless to say that it can be suitably used as a vibration isolation mechanism in a brush cutter using a model engine, and various modifications can be made without departing from the spirit of the present invention.

[Brief description of drawings]

FIG. 1 is a side view of a main part of a brush cutter incorporating a vibration isolation mechanism according to the present invention.

FIG. 2 is a cross-sectional view taken along the line AA of the brush cutter shown in FIG.

3 is a perspective view of a cylindrical holder of a vibration isolation mechanism in the brush cutter shown in FIG. 1. FIG.

FIG. 4 is a cross-sectional explanatory view of a brush cutter incorporating a conventional vibration isolation mechanism.

FIG. 5 is a cross-sectional explanatory view of a brush cutter that incorporates another conventional vibration isolation mechanism.

[Explanation of symbols]

20 anti-vibration mechanism, 22 clutch case, 2
4 cushioning material, 26 cylindrical holder, 28 drive shaft pipe, 30 tightening bolt, 32 centrifugal clutch, 34 clutch drum, 36 boss,
38 bearings, 40 locking holes, 42 flanges, 44 flexible engagement parts,
46 split grooves,

Claims (2)

[Scope of utility model registration request] 1. A cushioning material such as rubber is preliminarily assembled and arranged inside the clutch case, and a rotation stopping hole is formed at a predetermined position thereof, while a flange is provided at one end of a cylindrical holder made of synthetic resin. A bush cutter, which is formed and has a flexible engaging portion on the other end side to be fitted in the rotation stopping hole portion, and further forcibly press-fits and holds the drive shaft pipe into the cylindrical holder. Anti-vibration mechanism in. 2. The flexible engaging portion forms split grooves parallel to the longitudinal direction of the middle portion of the cylindrical holder, and the tips of these split grooves bulge outward in the radial direction of the holder. The anti-vibration mechanism in the brush cutter according to claim 1, wherein the anti-vibration mechanism is configured by providing a convex portion that does.