WO2015107731A1

WO2015107731A1 - Work machine

Info

Publication number: WO2015107731A1
Application number: PCT/JP2014/076944
Authority: WO
Inventors: 真紀桜木; 山本　淳; 徹也澤; 山本　稔
Original assignee: 株式会社マキタ
Priority date: 2014-01-14
Filing date: 2014-10-08
Publication date: 2015-07-23

Abstract

[Problem] To make it less likely for vibrations from an engine to be transmitted to a grip section of an operating pole and to make it less likely for an operator gripping the grip section of the operating pole to become fatigued due to vibrations. [Solution] A work machine (10) is provided with an operating pole (11) that comprises a grip section that is gripped by an operator, an engine (20) disposed on the rear end section of the operating pole (11), a rotating tool (32) that is disposed on the front end section of the operating pole (11) and is rotated by the engine (20), and a power transmission shaft (12) that is supported rotatably within the operating pole (11) and transmits the drive of the engine (20) to the rotating tool (32). A mounting frame (40) on which the engine (20) is mounted is integrally secured to the rear end section of the operating pole (11), and the mounting frame (40) is provided with elastic members (43, 44) that support the engine (20) so as to prevent vibration.

Description

Working machine

The present invention relates to a working machine such as a brush cutter that rotates a rotary tool by a prime mover, and more particularly, to a working machine provided with a prime mover at a rear end portion of an operating rod having a gripping part that a worker grips.

Patent Document 1 discloses a brush cutter for cutting grass, turf, and the like. This brush cutter has an operating rod attached with a handle gripped by an operator, an engine-type prime mover provided at the rear end portion of the operating rod, a rotary blade provided at the front end portion of the operating rod and rotated by the prime mover, And a power transmission shaft that is rotatably supported in the operating rod and transmits the drive of the prime mover to the rotary blade. In this brush cutter, when the prime mover is driven, the rotary blade is rotated by the driving force transmitted from the prime mover by the power transmission shaft, and the operator operates the handle to move the rotary blade parallel to the ground. This cuts the grass and grass that grows from the ground.

JP 2013-119847 A

In the brush cutter described above, there was a problem that the vibration when the prime mover is driven is transmitted from the operating rod to the handle, and the operator who grips the handle is easily fatigued by the vibration. In particular, because the prime mover that rotates the rotary blade is an engine-type prime mover, the prime mover vibrates in various directions by vibrations caused by the piston reciprocating in the cylinder, vibrations of the crankshaft rotated by the reciprocating piston, and the like. However, it was easy for the workers to get tired when working for a long time. An object of the present invention is to make it difficult for vibration of a prime mover to be transmitted to a grip portion of an operating rod and to make an operator who grips the grip portion of an operating rod less likely to get tired due to vibration.

In order to solve the above-described problems, the present invention provides an operating rod having a gripping portion to be gripped by an operator, a prime mover provided at the rear end portion of the operating rod, and a front end portion of the operating rod that is rotated by the prime mover. In a work machine equipped with a rotating tool that rotates and a power transmission shaft that is rotatably supported in the operating rod and transmits the drive of the prime mover to the rotating tool, a mounting frame that mounts the prime mover is integrated at the rear end of the operating rod And an elastic member for supporting the prime mover in a vibration-proof manner is provided on the mount frame.

In the work machine configured as described above, the mount frame on which the prime mover is mounted is integrally fixed to the rear end portion of the operation rod, and the mount frame is provided with an elastic member that supports the prime mover in a vibration-proof manner. This vibration is less likely to be transmitted to the operating rod with the mount frame fixed by the elastic member, and even if the operator grips the grip portion provided on the operating rod, the vibration does not easily cause fatigue. In one embodiment of this working machine, the mount frame has an upright portion that is fixed to the rear end portion of the operating rod and extends up and down, and a pedestal portion that extends rearward from the lower end of the upright portion. It is preferable to provide between the rear surface of the standing portion and the front portion of the prime mover, and between the upper surface of the pedestal portion and the lower portion of the prime mover. Further, the elastic member provided between the rear surface of the standing part and the front part of the prime mover employs a compression spring extending in the front-rear direction, and the elastic member provided between the upper surface of the base part and the lower part of the prime mover extends in the vertical direction. A compression spring should be used.

In order to solve the above-described problems, the present invention provides an operating rod having a gripping portion to be gripped by an operator, a prime mover provided at a rear end portion of the operating rod, and a prime mover provided at a front end portion of the operating rod. And a support body fixed to the outer peripheral portion of the operation rod, and a support that is rotatably supported in the operation て and a power transmission shaft that transmits the drive of the prime mover to the rotary tool. Provided is a working machine comprising a dynamic vibration absorber having a mass body spaced apart from the outside of the body and an elastic body that swingably supports the mass body with respect to a support body. Is.

In the working machine configured as described above, the dynamic vibration absorber reduces the vibration transmitted to the operating rod by swinging the mass body so as to cancel the vibration caused by the driving of the prime mover and the rotation of the power transmission shaft, The vibration of the grip portion of the heel is also suppressed. As a result, even if the operator grips the grip portion, it is less likely to get tired by the vibration transmitted from the prime mover or the like. In particular, in this working machine, it is preferable that the elastic body supports the mass body so as to be swingable in three degrees of freedom of translation and three degrees of rotation relative to the support body. In this case, the prime mover vibrates in any direction. Even if it does, it can rock | fluctuate so that a mass body may cancel the vibration by the drive of a motor | power_engine, and rotation of a power transmission shaft. In addition, since this dynamic vibration absorber can be used with any prime mover that vibrates in any direction, this dynamic vibration absorber can be used in various types of work machines that have different vibration directions depending on the arrangement and specifications of the prime mover. It was possible and the versatility of this dynamic vibration absorber could be increased.

In the working machine configured as described above, it is preferable that a dynamic vibration absorber is provided between the prime mover and the gripping portion. In this case, the dynamic vibration absorber is used before the vibration of the prime mover is transmitted to the gripping portion. Vibration can be reduced, and the vibration of the prime mover is less likely to be transmitted to the gripping part.

It is a perspective view of the brush cutter which is one Embodiment of the working machine of this invention. It is a longitudinal cross-sectional view along the front-back direction of an engine. It is the side view to which the rear part of FIG. 1 was expanded. It is a graph which shows the relationship between the natural frequency of the vibration system which consists of an engine, a mount frame, and a compression spring, and the frequency of the vibration produced by the drive of an engine. It is a perspective view of the brush cutter which is other embodiment of the working machine of this invention. It is a longitudinal cross-sectional view along the front-back direction of an engine. (A) It is the longitudinal cross-sectional view along the front-back direction of the part which provided the dynamic vibration absorber of the operating rod, (b) It is sectional drawing of an AA line.

Hereinafter, a brush cutter as an embodiment of the working machine of the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, the brush cutter 10 is provided with a long and narrow cylindrical operation rod 11 extending in the front-rear direction, an engine (prime mover) 20 at the rear end portion of the operation rod 11, and a front end portion of the operation rod 11. And a cutter unit 30 having a rotary blade (rotary tool) 32 that is rotated by the engine 20. Further, a power transmission shaft 12 that transmits the drive of the engine 20 to the rotary blade 32 is rotatably supported in the operation rod 11 via a bearing member. A loop handle (gripping part) 13 having a loop shape is provided in the middle part in the front-rear direction of the operation rod 11, and a grip handle (gripping part) 14 is provided on the rear side of the loop handle 13.

As shown in FIG. 2, the engine 20 includes a cylinder block 21 in which a crankcase 21a and a cylinder 21b are integrally provided at a lower portion, and a piston 22 can reciprocate in the vertical direction in the cylinder block 21. Contained. A combustion chamber 23 is formed between the upper surface of the piston 22 and the cylinder head 21 c at the upper end of the cylinder block 21. The cylinder head 21c is provided with an intake port that guides the air-fuel mixture generated by the carburetor to the combustion chamber 23 and an exhaust port that guides the exhaust gas generated in the combustion chamber 23 to the exhaust muffler (both not shown).

A crankshaft 24 is provided in the crankcase 21a, and the crankshaft 24 is supported so as to be rotatable about an axis whose front-rear direction is an axial direction. A piston 22 is connected to the crankshaft 24 via a connecting rod 25, and the reciprocating motion of the piston 22 in the vertical direction is converted into the rotational motion of the crankshaft 24. A flywheel 26 is provided at the front end of the crankshaft 24, and the flywheel 26 has a function of stabilizing the rotation of the crankshaft 24 and cooling the inside of the engine 20. A centrifugal clutch 27 is provided at the front end of the crankshaft 24 on the front side of the flywheel 26. The centrifugal clutch 27 allows the crankshaft 24 to rotate when the rotational speed of the crankshaft 24 exceeds a predetermined value. It is transmitted to the power transmission shaft 12.

As shown in FIG. 1, the cutter unit 30 includes a front end housing 31 fixed to the front end portion of the operation rod 11, and a rotating shaft (not shown) is rotatably supported by the front end housing 31. A bevel gear (not shown) is fixed to the base end portion of the rotation shaft, and the bevel gear fixed to the front end portion of the power transmission shaft 12 is engaged with the bevel gear, and the rotation of the power transmission shaft 12 causes the bevel gear to rotate. Is transmitted to the rotating shaft. The tip of the rotating shaft protrudes below the front end housing 31, and a rotary blade 32 is attached to the tip of the rotating shaft. Although the rotary blade 32 of this embodiment uses a nylon cord, it may use a disk-shaped rotary blade having a blade portion on the outer peripheral portion.

1 and 3, the mount frame 40 is fixed to the rear end of the operation rod 11, and the engine 20 is mounted on the mount frame 40 in a vibration-proof manner. The mount frame 40 includes an upright portion 41 that is fixed to the rear end portion of the operation rod 11 and extends up and down, and a pedestal portion 42 that extends rearward from the lower end of the upright portion 41. The mount frame 40 is provided with a pair of left and right first compression springs (elastic members) 43 between the rear surface of the upright portion 41 and the front portion of the engine 20, and the upper surface rear portion of the pedestal portion 42 and the rear lower portion of the engine 20. A pair of left and right second compression springs (elastic members) 44 are provided between them. The first compression spring 43 extends in the front-rear direction, and supports the engine 20 so that it can expand and contract in the front-rear direction and swing in directions crossing the front-rear direction (vertical direction and left-right direction). The second compression spring 44 extends in the vertical direction, and supports the engine 20 so that it can expand and contract in the vertical direction and swing in directions intersecting the vertical direction (front-rear direction and left-right direction).

In the brush cutter 10 configured as described above, when the engine 20 is driven, the crankshaft 24 is rotated by the piston 22 reciprocating in the vertical direction, and the crankshaft 24 is connected to the power transmission shaft 12 by the centrifugal clutch 27. Then, the power transmission shaft 12 is rotated, and the rotation of the power transmission shaft 12 is transmitted to the rotation shaft through the pair of bevel gears in the front end housing 31, and the rotary blade 32 fixed to the rotation shaft rotates. The operator holds the loop handle 13 with one hand and the grip handle 14 with the other hand, and operates the

handles

13 and 14 to swing the rotary blade 32 left and right along the upper side of the ground. Grass, grass, etc. growing from the ground are cut off.

When the engine 20 is driven, the piston 22 reciprocates in the cylinder 21b of the cylinder block 21 in the vertical direction, so that the engine 20 vibrates in the vertical direction and the crankshaft 24 rotates in the crankcase 21a. As a result, the engine 20 vibrates around the axis in the front-rear direction.

In the brush cutter 10 of this embodiment, the mount frame 40 on which the engine 20 is mounted is fixed integrally to the rear end portion of the operation rod 11, and the first and second are supported on the mount frame 40 in a vibration-proof manner. Compression springs 43 and 44 are provided. Specifically, the mount frame 40 includes an upright portion 41 that is fixed to the rear end portion of the operating rod 11 and extends up and down, and a pedestal portion 42 that extends rearward from the lower end of the upright portion 41. A pair of left and right first compression springs 43 are provided between the rear surface and the front portion of the engine 20, and a pair of left and right second compression springs 44 are provided between the upper surface rear portion of the pedestal portion 42 and the rear lower portion of the engine 20. It was. The first compression spring 43 supports the engine 20 such that it can expand and contract in the front-rear direction and swing in the direction intersecting with the front-rear direction (vertical direction and left-right direction), and the second compression spring 44 can be expanded and contracted in the vertical direction The engine 20 is supported so as to be swingable in the direction intersecting with (the front-rear direction and the left-right direction). As shown in FIG. 4, since the engine 20 is mounted on the mount frame 40 in a vibration-proof manner by the first and second compression springs 43 and 44, the engine 20 and the mount frame 40 are connected to each other. The natural frequency of the vibration system composed of the second compression springs 43 and 44 can be greatly separated from the frequency generated from the vibration of the engine 20, and transmission of the vibration generated by the drive of the engine 20 can be reduced. It was. As a result, the vibration of the engine 20 is not easily transmitted to the operating rod 11 with the mount frame 40 fixed by the first and second compression springs 43 and 44, and the operator holds the

handles

13 and 14 provided on the operating rod 11. Even so, it became hard to get tired by vibration. The power transmission shaft 12 in the operation rod 11 rotates by driving the engine 20, and vibration due to the rotation of the power transmission shaft 12 may be transmitted to the operation rod 11, but the power transmission shaft 12 is covered in the operation rod 11. If an elongated tube (pipe member) is interposed and the tube is interposed in the operation rod 11 via a flexible elastic member such as rubber, it is possible to suppress the vibration of the power transmission shaft 12 from being transmitted to the operation rod 11. Further, the power transmission shaft 12 is not limited to a long rod-shaped shaft member, and may be one using a flexible long shaft member such as a flexible shaft. When a long shaft member is used, vibration may occur due to rotation of the power transmission shaft 12, but vibration can be suppressed by a flexible elastic member interposed outside the tube.

Further, as a method for making it difficult to transmit the vibration of the engine 20 or the like to the

handles

13 and 14, a flexible elastic member such as rubber is interposed between the operation rod 11 and the

handles

13 and 14. It is also possible to suppress vibration from being transmitted from the operation rod 11 to the

handles

13 and 14. However, in this case, the

handles

13 and 14 may be swayed by the flexible elastic member interposed between the operation rod 11 and the operability of the

handles

13 and 14 may be reduced. On the other hand, if the engine 20 is mounted on the mount frame 40 fixed to the rear end of the operation rod 11 via the first and second compression springs 43 and 44 as in the present invention, each handle 13, Since it is not necessary to interpose a flexible elastic member such as rubber between the operation lever 11 and the operation rod 11, the

handles

13 and 14 can be fixed to the operation rod 11 in a stable state. It was possible to reduce both the transmitted vibration and maintain the operability of the

handles

13 and 14.

In the above embodiment, the compression springs 43 and 44 are employed as the elastic members. However, the present invention is not limited to this, and the other elastic members may be a flexible spring such as a leaf spring, a cylindrical or columnar rubber, or the like. A body, an air spring, or the like may be employed, and even when this is done, the same effects as described above can be obtained.

In the above embodiment, the operation rod 11 uses a straight cylindrical tube member, but the present invention is not limited to this, and uses a bent tube member having a curved tip. In this way, the same effect can be obtained.

In the above embodiment, the brush cutter using the loop handle 13 and the grip handle 14 as the grip portion has been described. However, the present invention is not limited to this, and only one of the loop handle 13 and the grip handle 14 is used. The same effect can be obtained even with a brush cutter that employs a U-shaped handle instead of the employed brush cutter or the loop handle 13 and the grip handle 14.

In the above embodiment, a brush cutter using a rotary blade as a rotary tool has been described. However, the working machine of the present invention is not limited to this, and a polisher such as a polisher or a grinder using a polisher as a rotary tool. It can be applied to the above.

5 to 7 show other embodiments of the working machine according to the present invention. In this embodiment, the prime mover 20 substantially the same as the prime mover 20 in the first embodiment described above is directly assembled to the rear end portion of the operating rod 11, and the dynamic vibration absorber 50 described later is connected to the prime mover 20 and the grip handle (gripping part). ), And the other components are the same as those in the first embodiment. Therefore, the same members and the same parts are denoted by the same reference numerals, and the description thereof is as follows. Omitted.

Thus, in the second embodiment, the operating rod 11 having the

grip portions

13 and 14 that the operator grips, the prime mover 20 provided at the rear end portion of the operating rod 11, and the front end portion of the operating rod 11 In a working machine provided with a rotary tool 32 that is provided and rotated by a prime mover, and a power transmission shaft 12 that is rotatably supported in the operation rod 11 and transmits the drive of the prime mover 20 to the rotary tool 32, A support body 51 fixed to the outer periphery, a mass body 52 spaced apart from the outside of the support body 51, and an elastic body 55 that supports the mass body 52 so as to be swingable with respect to the support body 51. The working machine 10A is provided with the dynamic vibration absorber 50 provided.

As shown in FIGS. 5 and 7, the operating rod 11 is provided with a dynamic vibration absorber 50, and the dynamic vibration absorber 50 is mainly for reducing vibration transmitted from the engine 20 to the operating rod 11. . The dynamic vibration absorber 50 is disposed between the grip handle 14 and the engine 20 at the rear portion of the operation rod 11. The dynamic vibration absorber 50 includes a support body 51 fixed to the outer peripheral portion of the rear part of the operation rod 11, a mass body 52 that is spaced apart from the support body 51, and a mass body 52 that swings the mass body 52 relative to the support body 51. And an elastic body 55 that is movably supported. The support 51 has a short cylindrical shape, and eight mounting holes 51 a extending in the radial direction are formed at equal intervals in the circumferential direction on the periphery of the support 51. These mounting holes 51a are for mounting the elastic body 55, and are stepped holes in which two cylindrical holes having a large outer peripheral side and a small inner peripheral side are arranged concentrically.

The mass body 52 has a short cylindrical inner portion 53 having a larger diameter than the support 51 and a short cylindrical outer portion 54 fitted to the outer peripheral surface of the inner portion 53. The outer portion 54 is a structure using a metal member such as stainless steel. Eight through holes 53a extending in the radial direction are formed at equal positions in the circumferential direction at positions facing the mounting holes 51a of the support body 51 in the inner portion 53 of the mass body 52, and these through holes 53a are elastic bodies. The elastic body 55 is attached to the mass body 52 by accommodating the middle part to the front end of 55. The outer portion 54 is fitted so as to cover the inner portion 53 from the outside, and is fixed to the inner portion 53 with screws. The outer portion 54 is provided with a through hole 54a having a smaller diameter than the through hole 53a at a position facing the through hole 53a of the inner portion 53, and the elastic body 55 is prevented from being detached by the peripheral portion of the through hole 54a. .

The elastic body 55 is for supporting the mass body 52 on the support body 51 so as to be swingable in a state where the mass body 52 is concentrically spaced from the support body 51. The elastic body 55 is made of a flexible elastic member such as rubber having a cylindrical shape. The elastic body 55 is mounted with its base end positioned in the mounting hole 51a of the support 51 in a state where the base end is secured by the bottom of the mounting hole 51a of the support 51, and the tip is attached to the outer portion of the mass body 52. In a state where it is prevented from being detached by 54, the tip side from the intermediate part is positioned and attached in the through hole 53 a of the inner part 53 of the mass body 52. The mass body 52 is supported by the eight elastic bodies 55 so as to be swingable with respect to the support body 51 with six degrees of freedom of three translational degrees of freedom and three degrees of freedom of rotation. The elastic body 55 is not limited to a flexible elastic member such as rubber, and may be one using a spring member such as a coil spring. In this embodiment, eight elastic bodies 55 are arranged at equal intervals in the circumferential direction. However, the present invention is not limited to this, and three or more elastic bodies 55 may be arranged at equal intervals. Further, the shape is not limited to a cylinder, and the support body 51 and the mass body 52 may be joined (for example, integrally molded) with an elastic body such as a whole circumference rubber.

In the brush cutter 10A configured as described above, when the engine 20 is driven, the crankshaft 24 is rotated by the piston 22 reciprocating in the vertical direction, and the crankshaft 24 is connected to the power transmission shaft 12 by the centrifugal clutch 27. Then, the power transmission shaft 12 is rotated, and the rotation of the power transmission shaft 12 is transmitted to the rotation shaft through the pair of bevel gears, and the rotary blade 32 fixed to the rotation shaft rotates. The operator holds the loop handle 13 with one hand and the grip handle 14 with the other hand, and operates the

handles

When the engine 20 is driven, the piston 22 reciprocates in the cylinder 21b of the cylinder block 21 in the vertical direction, so that the engine 20 vibrates in the vertical direction and the crankshaft 24 rotates in the crankcase 21a. As a result, the engine 20 vibrates around the axis in the front-rear direction, and these vibrations of the engine 20 are transmitted to the operation rod 11. Further, vibration due to the rotation of the power transmission shaft 12 that is rotated by driving the engine 20 is also transmitted to the operation rod 11 through the bearing member.

The brush cutter 10 </ b> A according to this embodiment includes a support body 51 fixed to the outer periphery of the operation rod 11, a mass body 52 that is spaced apart from the outside of the support body 51, and a mass body that rocks the support body 51. A dynamic vibration absorber 50 having an elastic body 55 that is movably supported is provided. The dynamic vibration absorber 50 is provided on the operation rod 11 by reducing the vibration transmitted to the operation rod 11 by swinging the mass body 52 so as to reduce the vibration caused by the driving of the engine 20 and the rotation of the power transmission shaft 12. The vibration of the loop handle 13 and the grip handle 14 is also suppressed. As a result of measuring the triaxial acceleration of the vibration of the loop handle 13 and the grip handle 14 in accordance with IEC 60335-2-91, the vibration generated in the loop handle 13 is a vibration in the vertical direction as compared with the case where no dynamic vibration absorber is provided. Was suppressed to about 10%. In addition, the vibration generated in the grip handle 14 is about 8% in the left-right direction, about 9% in the front-rear direction, and about 14% in the up-down direction compared to the case without the dynamic vibration absorber. It was possible to greatly suppress. As a result, even if the operator grips the loop handle 13 and the grip handle 14, it is less likely to get tired due to vibration generated in the engine 20 or the like.

In particular, in the brush cutter 10A, the dynamic vibration absorber 50 is configured such that the mass body 52 is supported by the support body 51 by the elastic body 55 so that the mass body 52 can swing freely in 6 degrees of freedom of translation and 3 degrees of rotation. Thereby, not only the engine 20 vibrates in the vertical direction but also the mass body 52 does not cause the mass body 52 even when complicated vibrations are caused due to a plurality of vibrations such as when the front-rear direction is vibrated in a direction rotating around the axis. Even if the operator grips the

handles

13 and 14 by swinging so as to reduce these vibrations, it becomes hard to get tired. Further, even when this dynamic vibration absorber 50 is adopted in a brush cutter of a model in which the direction of vibration differs depending on the arrangement and specifications of the engine 20, for example, when the piston 22 is inclined from an upright state, The vibration transmitted to the operation rod 11 can be suppressed, and the versatility of the dynamic vibration absorber 50 can be increased.

Further, in the brush cutter 10A, the dynamic vibration absorber 50 is provided between the engine 20 and the grip handle 14 (including the loop handle 13). As a result, the dynamic vibration absorber 50 can reduce the vibration transmitted from the engine 20 to the operating rod 11 before transmitting it to the grip handle 14 and the loop handle 13, and the vibration of the engine 20 is reduced to the grip handle 14 and the loop handle 13. It became more difficult to communicate. The dynamic vibration absorber 50 is optimally provided between the engine 20 of the operating rod 11 and the grip handle 14 (including the loop handle 13), but is not limited to this. For example, the dynamic vibration absorber 50 is provided. Even if it is provided between the loop handle 13 and the grip handle 14 of the operating rod 11 or in front of the loop handle 13, the vibration transmitted from the engine 20 to the operating rod 11 can be reduced.

handles

13 and 14. However, in this case, the

handles

13 and 14 may be reduced. On the other hand, if the operation rod 11 is provided with the dynamic vibration absorber 50 as in the present invention, a flexible elastic member such as rubber needs to be interposed between the

handles

13 and 14 and the operation rod 11. Therefore, the

handles

13 and 14 can be fixed to the operation rod 11 in a stable state, vibrations transmitted to the

handles

13 and 14 can be reduced, and the operability of the

handles

13 and 14 can be maintained. I was able to balance both.

DESCRIPTION OF

SYMBOLS

10, 10A ... Work machine (brusher), 11 ... Operation rod, 12 ... Power transmission shaft, 13 ... Gripping part (loop handle), 14 ... Gripping part (grip handle), 20 ... Motor (engine), 32 ... Rotation Tool (rotating blade), 40 ... mount frame, 41 ... standing part, 42 ... pedestal part, 43 ... elastic member (first compression spring), 44 ... elastic member (second compression spring), 50 ... dynamic vibration absorber , 51 ... support, 52 ... mass body, 53 ... inner part, 54 ... outer part, 55 ... elastic body.

Claims

An operating rod having a gripping part to be gripped by an operator;
A prime mover provided at the rear end of the operating rod;
A rotary tool provided at the front end of the operating rod and rotated by the prime mover;
In a working machine comprising a power transmission shaft that is rotatably supported in the operation rod and transmits the drive of the prime mover to the rotary tool,
A mounting frame for mounting the prime mover is integrally fixed to a rear end portion of the operation rod,
A working machine, wherein the mount frame is provided with an elastic member for supporting the prime mover in a vibration-proof manner.
The working machine according to claim 1,
The mount frame has an upright portion that is fixed to a rear end portion of the operation rod and extends up and down, and a pedestal portion that extends backward from a lower end of the upright portion,
A working machine characterized in that the elastic member is provided between the rear surface of the standing part and the front part of the prime mover, and between the top surface of the pedestal part and the lower part of the prime mover.
The work machine according to claim 2,
The elastic member provided between the rear surface of the upright part and the front part of the prime mover employs a compression spring extending in the front-rear direction, and the elastic member provided between the upper surface of the pedestal part and the lower part of the prime mover A working machine characterized by adopting a compression spring extending in the direction.
An operating rod having a gripping part to be gripped by an operator;
A prime mover provided at the rear end of the operating rod;
A rotary tool provided at the front end of the operating rod and rotated by the prime mover;
In a working machine comprising a power transmission shaft that is rotatably supported in the operation rod and transmits the drive of the prime mover to the rotary tool,
A support body fixed to the outer periphery of the operation rod; a mass body spaced apart from the support body; and an elastic body that swingably supports the mass body with respect to the support body. A working machine comprising the dynamic vibration absorber.
The work machine according to claim 4,
The working machine characterized in that the elastic body supports the mass body so as to be swingable with respect to the support body in three degrees of translation and three degrees of rotation.
The working machine according to claim 4 or 5,
A working machine, wherein the dynamic vibration absorber is provided between the prime mover and the grip portion.