JPS6038341Y2 - Brush cutter transmission device - Google Patents

Description

[Detailed description of the invention] The invention includes a connecting rod that connects the engine to a support that rotatably supports the rotary blade, and a transmission shaft that penetrates the inside of the connecting rod and drives the rotary blade. This relates to the transmission device of the installed brush cutter.

Conventionally, this type of transmission device for a brush cutter is equipped with a long, rigid transmission shaft made of steel, which causes vibrations due to rotation and large vibrations due to resonance, causing damage to the transmission part.

For this reason, a bearing body having a bearing hole that rotatably supports the outer periphery of the transmission shaft is provided on the inner diameter portion of the connecting rod by adhering and fixing it with an adhesive at appropriate intervals.

For this reason, the work of inserting, positioning, and gluing the bearing body into the long connecting rod is troublesome, and the efficiency of the assembly work is hindered.

The present invention includes a bearing body that is equipped with a bearing hole that rotatably supports the outer periphery of a rigid transmission shaft to prevent it from curving in the axial direction, and a plurality of protrusions that fit into the inner diameter of the connecting rod. By providing the bearing body inside the connecting rod and connecting it over the entire length, there is no need to glue the bearing body to the connecting rod with adhesive, making it easy to insert and remove, and improve the efficiency of assembly work. The aim is to provide a transmission device for a brush cutter that is capable of

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

In the figure, 1 is a support that rotatably supports the rotary blade 3, 5 is a cylindrical connecting rod that connects the engine 7 and the support 1, and 9 is a cylindrical connecting rod that passes through the inside of the connecting rod 5 to connect the engine 7. This is a rigid transmission shaft made of steel for transmitting power to the rotary blade 3.

11 is a grip part fixed to the connecting rod 5; 13 is a grip part provided on the handle 15 which is fixed to the connecting rod 5; 17 is a handle 1
This is the throttle lever installed at 5.

Reference numeral 19 denotes a crankshaft pivotally supported by the crank case 21 of the engine 7, and reference numeral 23 has one end pivotally connected to a crank arm 25 provided on the crankshaft 19 by a crank pin 27, and the other end pivotally connected to a piston (not shown). The crankshaft 19 is rotated by the reciprocating movement of a piston (not shown).

29 is a centrifugal clutch provided at the end of the crankshaft 19;
Reference numeral 1 designates a clutch drum provided outside the centrifugal clutch 29, and is fixed to a rotating shaft 33.

Reference numeral 35 denotes a clutch housing that is fixed and integrated with the crankcase 21, and 37 is a lid that is fixed to the clutch housing 35 with bolts (not shown), which pivotally supports the rotating shaft 33 with bearings 39 and 39. There is.

One end of the connecting rod 5 is fitted into an engaging part 43 divided by a notched groove 41 at the end of the lid part 37 and fixed by a screw 45.

47 is a bearing hole 49 that rotatably supports the outer periphery of the transmission shaft 9.
The bearing body is made of visible synthetic resin and has a plurality of protrusions 51, 51 . that fit into the inner diameter part of the connecting rod 5.・
... are provided and are continuously connected to the inside of the connecting rod 5 over almost the entire length.

53 is a washer that locks the end of the bearing body 47, and 55 is a threaded portion that connects the transmission shaft 9 and the rotating shaft 33.

In the above configuration, the power of the engine 7 is transmitted to the crankshaft 19, the centrifugal clutch 29, the clutch drum 31. It is transmitted to the transmission shaft 9 via the rotating shaft 33, and rotationally drives the rotary blade 3.

Since the transmission shaft 9 has an elongated shape, it tends to bend and vibrate due to rotation, but it is supported by the bearing body 47 and does not generate vibration.

When assembling, insert the bearing body 47 into the connecting rod 5, insert the transmission shaft 9 into the bearing hole 49, and engage and fix the end of the connecting rod 5 to the engaging part 43 of the lid part 37. Next, the rotary shaft 33 is engaged with the transmission shaft 9 and is pivotally supported by the lid portion 37, and then the lid portion 37 is engaged with the clutch housing 35.

Furthermore, the bearing bodies 47, 47, . . . , which are divided and provided separately, may be connected by projections 51, 51, . . . provided in the longitudinal direction.

Alternatively, a cylindrical body that fits into the inner diameter portion of the connecting rod 5 may be provided continuously over almost the entire length, and the bearing body may be connected and supported by this cylindrical body via a protrusion.

In this case, it is within the scope of the present invention that the bearing body or the protrusion be formed continuously in the longitudinal direction or divided into parts.

As described above, the present invention includes a connecting rod that connects an engine to a support that rotatably supports a rotary blade, and a rigid power transmission shaft that penetrates the inside of the connecting rod and drives the rotary blade. and a bearing body having a bearing hole rotatably supporting the outer periphery of the transmission shaft and a plurality of protrusions that fit into the inner diameter part of the connecting rod is installed inside the connecting rod. Since the transmission device of the brush cutter is connected over the entire length, resonance of the transmission shaft can be prevented, and there is no need to glue the bearing body to the connecting rod, making it easy to insert and remove, preventing resonance of the transmission shaft. In addition, the assembly efficiency can be improved, the bearing body does not move in the axial direction, and the transmission shaft can be stably supported, and the protrusion allows it to be supported on the connecting rod. Therefore, it is possible to absorb the vibrations of the transmission shaft and prevent the vibrations from being transmitted to the hands of the operator who grips the grip provided on the connecting rod.

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.

[Brief explanation of drawings]

FIG. 1 is a perspective explanatory view of a brush cutter, FIGS. 2 and 3 are a side sectional view and a front sectional view, respectively, of one embodiment of the present invention, and FIG. 4 is a side sectional view of essential parts. Explanation of the symbols representing the main parts of the drawing, 1...
Support body, 3... Rotating blade, 5... Connection rod, 7... Engine, 9... Transmission shaft, 4
7...Bearing body, 49...Bearing hole, 51
······protrusion.

Claims (1)

[Scope of utility model registration request] A linear connecting rod 5 that connects the support 1 that rotatably supports the rotary blade 3 and the engine 7, and a rigid power transmission shaft that penetrates the inside of the connecting rod 5 and drives the rotary blade 3. 9
a bearing hole 49 for rotatably supporting the outer periphery of the transmission shaft 9 to prevent it from curving in the axial direction; and a plurality of protrusions 51, 51 . . . . A transmission device for a brush cutter, characterized in that a bearing body 47 is provided inside the connecting rod 5 and connected over almost the entire length thereof.