JPH0323052Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a brush cutter, and more specifically to an operating pipe that connects a cutting blade unit provided at one end and an engine unit provided at the other end. Regarding improvements.

[Conventional technology]

As shown in FIG. 6, a conventionally well-known brush cutter has a cutting blade 6 rotatably supported on one end of an operating pipe 1 having a required length via a gear case 5. A small engine unit 7 as a power source is attached to the other end. It is transmission-connected to transmit rotational torque to the blade 6 side.

Then, the operator holds the handle 2 provided at the middle part of the operating pipe 1 and swings the cutting blade 6 on the tip side from side to side to perform the cutting operation. Because of this usage pattern, it is desired that the overall weight of the brush cutter be made as light as possible to reduce the weight burden on the operator.

[The problem that the idea aims to solve]

In this case, since the operating pipe in the conventional brush cutter was constituted by a hollow pipe with a circular cross section, the following problems occurred.

The operating pipe 1 is used when an operator performs mowing work by swinging the cutting blade 6 on the tip side from side to side while holding the handle 2 provided in the middle part of the operating pipe 1, which is relatively long. Since the pipe needs to have a certain thickness and rigidity so as not to bend, it has not been possible to reduce the weight of the operating pipe 1 in the above-mentioned weight reduction.

Furthermore, the handle 2 attached to the operation pipe is attached via a fastening boss 3, as shown in FIGS. Member 3a
The structure is such that the operating pipe 1 is sandwiched in the recess between the upper and lower members 3b, and both members 3a and 3b are tightened together with bolts 4.If the bolts 4 become slightly loosened due to vibrations caused by work, etc. There was a problem that the handle 2 rotated.

The above-mentioned problem occurs not only between the handle 2 and the operating pipe 1, but also between the operating pipe and the gear case 4 that pivotally supports the cutting blade 6, and between the operating pipe and the engine unit 7. Since rotation phenomenon occurs, there was a problem that required a special rotation prevention structure.

The present invention was proposed in response to the above-mentioned problems, and it is possible to reduce the weight of the operation pipe while maintaining the required rigidity, and to ensure that the connection part to the operation pipe does not rotate. The purpose is to provide a hair removal machine.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention connects a cutting blade unit provided on one end side and an engine unit provided on the other end side, and provides a transmission for transmitting the rotational output of the engine unit to the cutting blade unit side. In the operation pipe of a brush cutter with a shaft inserted inside, the operation pipe has a non-circular cross section that has a high bending rigidity in a direction perpendicular to the pipe axis, such as a polygonal cylinder or an elliptical cylinder. It is characterized by being constituted by a hollow cylindrical body having a shape.

[Effect]

When the operating pipe is constructed of a hollow cylinder having a non-circular cross-sectional shape as described above, the bending rigidity in the direction orthogonal to the pipe axis is increased compared to a hollow pipe having a circular cross-section. First, the deflection of the operating pipe can be reduced, and the wall thickness of the pipe can be made thinner by the increased rigidity, thereby reducing the weight while maintaining the required rigidity of the operating pipe. This can greatly contribute to reducing the overall weight of the brush cutter.

In addition, the handle connected to the axial circumference of the operating pipe, the cutting blade unit, the engine unit, etc. connected to the end are prevented from rotating in the circumferential direction due to the anti-rotation effect of the non-circular cross section. Therefore, there is no need to provide a special locking structure to the joint, and the structure of the joint can be simplified.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3.

In FIG. 1, reference numeral 11 indicates an operating pipe of a brush cutter, and the illustrated one is a manipulating pipe having a required length cut along a plane perpendicular to the axial direction at the midpoint of the length. The operating pipe 11 shown here is constituted by a hollow cylinder having a hexagonal cylindrical cross section. Note that the reference numeral 14 indicates a handle attached to the middle part of the operation pipe 11.
The upper and lower halves of the fastening bosses 12 and 13 for fastening the handle 14 to the operating pipe 11 also have a concave space formed in their mating surfaces in a hexagonal shape corresponding to the operating pipe 11.

FIG. 2 shows another embodiment in which the cross-sectional shape of the operating pipe 11 is different. The operating pipe 11 shown in FIG. 2 is constituted by a hollow cylinder having an elliptical cross-sectional shape. The elliptical hollow cylinder body is arranged such that its long axis side is located parallel to the horizontal plane (the direction in which the operating pipe 11 is swung left and right), and its short axis side is located in the vertical direction that intersects with the horizontal plane. In this embodiment, the upper and lower halves of the fastening bosses 12 and 13 for fastening the handle 14 to the operating pipe 11 have concave spaces formed in their mating surfaces in an elliptical shape corresponding to the operating pipe 11. Ru.

FIG. 3 shows another embodiment in which the cross-sectional shape of the operation pipe 11 is further changed, and in this embodiment, the elliptical hollow cylinder shown in FIG. The operating pipe 11 is constructed of a hollow cylinder having flat surfaces 11a formed on the upper and lower circumferential surfaces thereof, and an arcuate surface on the long axis side formed into a curved surface with a large radius.

When the operating pipe 11 is constructed of a hollow cylinder having a non-circular cross-sectional shape as shown in FIGS. As a result, the bending rigidity in the direction perpendicular to the pipe axis direction is increased.

As a result, the operation pipe 11 can reduce the bending of the pipe when mowing work is performed by swinging the cutting blade on the tip side left and right.

Furthermore, since the wall thickness of the pipe can be made thinner by the increase in the above-mentioned bending rigidity, the weight of the operating pipe can be reduced while maintaining the required rigidity, contributing to the weight reduction of the entire brush cutter.

In addition, the handle 14, which is connected to the axial circumference of the operating pipe 11, and the connecting parts, such as the cutting blade unit and engine unit, which are connected to the end of the pipe, are prevented from rotating in the circumferential direction by the rotation prevention effect of the non-circular cross section. Since this is prevented, there is no need to provide a special locking structure to the joints, and the structure of the joints can be simplified.

[Effect of idea]

As explained above, according to the present invention, the operating pipe of the brush cutter is constructed by a hollow cylinder having a non-circular cross-sectional shape, which is a simple method that allows the operation pipe to be perpendicular to the axial direction of the pipe. It is possible to increase the deflection rigidity in the direction, reduce the deflection of the operating pipe compared to conventional ones, and also make it possible to reduce the pipe wall thickness by the increased deflection rigidity. It is possible to reduce the weight of the brush cutter while maintaining the required rigidity, and this has the effect of greatly contributing to the weight reduction that has been strongly desired in brush cutters.

In addition, the handle, which is connected to the axial circumference of the operating pipe, the cutting blade unit, the engine unit, etc. that are connected to the end of the pipe, and other joints have non-circular cross sections that prevent rotation. Since rotation in the circumferential direction is prevented by the action, it is not necessary to provide a special rotation prevention structure to the joint portions, and the structure of the joint portions can also be simplified.

[Brief explanation of the drawing]

1 to 3 are partial sectional views showing the operation pipe of the brush cutter according to the present invention, and FIGS. 4 to 6 show the conventional example, and FIGS. FIG. 6 is a perspective view and a sectional view of a handle attachment portion attached to a pipe, and FIG. 6 is a perspective view of the entire brush cutter. 11... Operation pipe, 11a... Flat surface, 1
2, 13...Tightening boss, 14...Handle.

Claims (1)

[Claims for Utility Model Registration] A cutting blade unit is provided at one end of an operating pipe made of a hollow cylindrical body, and an engine unit is provided at the other end. In the brush cutter that rotates the brush cutter, the operation pipe of the brush cutter has a non-circular cross-sectional shape such as a polygonal cylinder or an elliptical cylinder that has a high bending rigidity in a direction perpendicular to the pipe axis direction. A brush cutter comprising a hollow cylindrical body.