JPH0210892Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention is applied to a connection device for a connection rod of a brush cutter, which is equipped with a connection rod that connects an engine to a bearing body that rotatably supports a rotary blade. This is related.

(b) Prior Art In a conventional connecting device for a connecting rod of a brush cutter, one end of the connecting rod is formed into a plane perpendicular to the axis, and the outer periphery of this end is connected to the connecting portion of the clutch housing or bearing body. The end surface of the connecting rod is positioned by abutting against the stepped locking surface provided inside the engaging hole, and the notch provided in the axial direction at the end of the connecting portion is laterally inserted. It was held in place by cutting and tightening bolts.

(c) Problems that the invention aims to solve Conventionally, the end face of the connecting rod was installed perpendicular to the axis, so the rotation force loosened the locking screw, causing the position in the rotation direction to change. There is a problem that the connecting rod may become distorted or the connecting rod may come off, and especially when the connecting portion of the clutch housing or the like is made of synthetic resin, there is a risk that the connecting rod may become loose due to permanent deformation and rotate.

(d) Means for solving the problem The present invention provides an inclined end surface that is inclined with respect to the axis line on the end face of the connecting rod, and an engagement hole that engages the outer periphery of one end of the connecting rod in the connecting part. At the same time, a locking surface for locking the inclined end surface was provided in the engagement hole.

(e) Effect A rotational force acts between the connecting rod and the connecting part due to the reaction force of the rotation of the transmission shaft, but since the inclined end face is locked to the locking surface, there is no rotation. Further, when inserting the connecting rod into the connecting portion, the inclined end surface is guided by the locking surface to perform positioning.

(f) Embodiment In FIGS. 1 to 6, the brush cutter 1 is constructed as follows. That is, the rotary blade 3 is rotatably supported by the bearing body 5, and the bearing body 5 is supported by the connecting rod 7.
It is connected to the engine 9 by. Connecting rod 7
A handle 11 is fixed in the middle of the handle 1.
Grip portions 13, 13 are provided at both ends of 1.
A hanger 15 and a protector 17 are provided at the rear of the connecting rod 7. A shoulder strap (not shown) is secured to the hanger 15. The protector 17 protects the lower back of the worker.
A cover 19 is fixed to the connecting rod 7 behind the rotary blade 3. A centrifugal clutch 23 is attached to the crankshaft 21 of the engine 9, and a boss shaft 2 is fixed to the center of a clutch drum 25 provided close to the outer periphery.
7 is pivotally supported by a synthetic resin clutch housing 29 that covers the centrifugal clutch 23 via bearings 31, 31. A spline shaft 37 at one end of a transmission shaft 35 for transmitting power to the rotary blade 3 is engaged with a spline hole 33 provided in the boss shaft 27 . The connecting portion 38 at the front end of the clutch housing 29 is provided with an engaging hole 39 that engages the outer periphery of the end of the connecting rod 7, and a notch 41 cut out in the axial direction.
It is fixed by a bolt 43 provided across the. An inclined end surface 45 that is inclined with respect to the axis is provided on the distal end surface of the connecting rod 7, and is engaged with a locking surface 47 provided in a stepped manner on the inner surface of the engagement hole 39.

The power of the engine 9 is transmitted from the crankshaft 21 to the centrifugal clutch 23, the clutch drum 25, and the boss shaft 2.
7. Rotate the rotary blade 3 via the transmission shaft 35. The worker wears a shoulder strap (not shown) on his shoulder, grips the grips 13, and uses the rotating rotary blade 3 to cut grass, etc. on the ground. Due to the rotational reaction force of the transmission shaft 35, the transmission shaft 35
The clutch housing 29 tries to rotate relative to each other, but in addition to the tightening force of the bolt 45, the inclined end surface 45 and the locking surface 47 are locked.
It can be fixed securely.

(g) Effect of the invention Since the invention has the configuration as described in the claims, it facilitates the positioning of the connecting rod and the connecting part in the circumferential direction and the axial direction during assembly, and the rotation of the power transmission shaft. The relative rotational movement between the connecting rod and the connecting portion due to the reaction force can be reliably and strongly stopped.

In the above-mentioned embodiment, the connection device on the clutch housing 29 side of the connection rod 7 has been described, but the present invention can be similarly applied to the connection device on the bearing body 5 side.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be implemented in other embodiments as well. Further, the symbols shown in the claims do not limit the technical scope of the present invention.

[Brief explanation of drawings]

Fig. 1 is a perspective explanatory view of a brush cutter equipped with a device according to the present invention, Fig. 2 is a side sectional view of one embodiment of the present invention, Fig. 3 is a side sectional view of main parts, Figs. Figure 5,
Figure 6 is a side sectional view, a front view, and a front view of other important parts, respectively.
FIG. 3... Rotating blade, 5... Bearing body, 7... Connecting rod,
9... Engine, 38... Connecting portion, 39... Engagement hole, 45... Inclined end surface, 47... Locking surface.

Claims (1)

[Scope of utility model registration request] In the connecting rod 7 that connects the bearing body 5 that rotatably supports the rotary blade 3 and the engine 9, an inclined end surface 45 that is inclined with respect to the axis line is provided on the end surface of the connecting rod 7.
is provided, and the connecting portion 38 connecting the connecting rod 7 is provided with a
An engagement hole 39 that engages the outer periphery of one end of the connecting rod 7
A connecting device for a connecting rod of a brush cutter, characterized in that a locking surface 47 for locking the inclined end surface 45 is provided in the locking hole 39.