JPS6142336Y2 - - Google Patents

Description

[Detailed description of the invention] This invention eliminates vibrations from the engine by juxtaposing and fixing an elastic detent and a damper to the engine-side end of the outer tube that covers the transmission shaft for driving the cutting blade. The present invention relates to a vibration isolating device for a brush cutter that reduces worker fatigue by absorbing and alleviating vibrations generated when the cutting blade is driven during brush cutting work, and that is lightweight and can be manufactured at low cost.

When a worker grasps the handle attached to the outer pipe that covers the power transmission shaft for mowing the mower and cuts weeds, shrubs, vines, etc., vibrations caused by the engine drive and Vibration is transmitted to the worker's hands via the clutch, clutch drum, clutch case, etc., which causes severe worker fatigue and makes it difficult to work for long periods of time. Anti-vibration methods such as interposing or attaching a vibration-isolating material made of a highly elastic material such as rubber or a combination of a vibration-isolating material and a "spring" between the clutch case and the outer tube or on the outer circumferential surface of the outer tube. However, even if such anti-vibration measures are taken, the structure as a whole will inevitably become more complex and the weight of the shock absorber as a whole will inevitably increase, placing an unreasonable load on workers. However, in cases where a vibration-proofing effect is desired when a wide range of frequencies are generated, the weight of the vibration-proofing material or the combination of the vibration-proofing material and the "spring" is particularly important. The increase was significant, and it was inevitable that workers would become fatigued much faster. Therefore, even if an anti-vibration effect can be expected, it tends to increase worker fatigue and also has the disadvantage of complicating the structure. However, it is desirable to simplify the structure and reduce the weight. Although these are extremely suitable, they have drawbacks such as the fact that they cannot always be guaranteed to be sufficient in terms of vibration mitigation and absorption.
Therefore, in order to correct the above-mentioned drawbacks, this idea was developed by juxtaposing a detent made of a highly elastic material such as rubber and a damper filled with gas or liquid at the end of the outer tube on the engine side. The aim is to provide a lightweight brush cutter vibration isolator that does not make the structure unnecessarily complicated, while also mitigating and absorbing vibrations and reducing worker fatigue. , a detent fixed to the outer tube in the longitudinal direction and a damper filled with gas or liquid are interposed in parallel between the outer tube that covers the transmission shaft and the clutch case.

To describe an embodiment of this invention with reference to the drawings below, the inside of a clutch case C is connected to the front of the engine E (in Figures 1 to 5, except for Figure 3, the left side is the front and the right side is the rear). A transmission in which a reduced diameter portion 3 at the front end of a protruding body 2 that can protrude forward of the clutch drum D is rotatably fitted into a ball bearing 1 mounted in the middle, and the rear end is fitted and fixed into the protruding body 2. Extend the shaft 4 forward and connect its front end to the gear housing G
It is connected to the cutting blade 5 via a group of interlocking gears (not shown) inside. In addition, a sheathing tube 7 is installed along the rear outer circumferential edge of the outer tube 6 that covers the transmission shaft 4 inside the clutch case C, and the sheathing tube 7 and the outer tube 6 are fastened with fasteners j such as screws or rivets. At the same time, a detent 8 made of an elastic material such as rubber is fixed to the outer peripheral edge of the front end of the cladding tube 7 by baking or the like, and a detent 8 is attached to the outer peripheral edge of the cladding tube 7 behind the detent 8.
An appropriate number (four in this case) of annular dampers 9 made of an elastic material such as rubber and having a circular cross section are arranged side by side, and gas or liquid d is filled in each of these dampers 9. In order to prevent the detent 8 from slipping out to the outside of the clutch case C,
A retaining plate 10 is fixed to the front end surface of the clutch case C with a retaining bolt b on the front surface of the detent 8.
As shown in FIG. 3, it is preferable that the detent 8 has a substantially rectangular shape with a slightly bulged corner portion e, but it is also possible to adopt a shape other than this, and the The tube 7 may be omitted in some cases.

Further, other embodiments of the damper are shown in FIGS. 4 and 5, respectively; in FIG. 4, the damper 19 is an annular damper 19 with an elliptical cross section, and in FIG. The damper 29 is shaped like a coil spring and has a circular cross section.

In the figure, F indicates a fuel tank 11, a backpack strap, 12 a handle, 13 a throttle lever, 14 a stop lever, and W a throttle wire.

Since this invention has the above-mentioned configuration, the engine E drives the power to the clutch drum D,
It is transmitted to the cutting blade 5 via the transmission shaft 4 and a group of interlocking gears,
Carry out mowing work. However, during the lever operation, a detent 8 made of a highly elastic material such as rubber and a damper 9, 19 or 29 filled with liquid or gas d are placed side by side between the clutch case C and the outer tube 6. Because of this, vibrations and shocks transmitted to the outer tube 6 from the engine side or the cutting blade side are absorbed or alleviated by the detent 8 and the dampers 9, 19, or 29. ) does not transmit severe vibrations or shocks to the hands of workers, so there is no reduction in efficiency due to early fatigue of workers, and the rotation stopper 8 prevents the outer tube 6 from unexpectedly rotating due to vibrations or shocks. Not only can accidents be prevented in advance, unexpected injuries to workers can be prevented, and work can be carried out safely, but the overall structure is extremely simple, making it robust and inexpensive to manufacture, making it convenient for users. In addition to being economical, the overall weight of the vibration isolating member does not increase significantly compared to conventional vibration isolating members, making it easy for users to handle and preventing damage. It has the practical benefit of being able to easily inspect, repair, or replace with a new one.

Although the dampers 9, 19, and 29 adopt the forms shown in FIGS. 2, 4, and 5, their functions as dampers are the same, and they are not limited to these forms. It's not even a thing.

[Brief explanation of the drawing]

The drawings are examples of this invention, and Figure 1 is a front view of the main parts of a brush cutter to which this invention is installed, and Figure 2 is a front view of the main parts of a brush cutter to which this invention is installed.
3 is a side view of the detent, FIG. 4 is a sectional view of the main part of an embodiment different from the damper in FIG. 2, and FIG. 5 is a further difference from the damper in FIG. 2. FIG. 6 is a sectional view of a main part of a different embodiment. C...Clutch case, 4...Transmission shaft, 6...
Outer tube, 8... Rotation stopper, 9, 19, 29... Damper, d... Gas or liquid.

Claims (1)

[Claims for Utility Model Registration] (1) A detent fixed to the outer tube along the front-back direction and a damper filled with gas or liquid are interposed in parallel between the outer tube that covers the transmission shaft and the clutch case. Anti-vibration device for brush cutters. (2) The vibration isolating device for a brush cutter according to claim 1, wherein both the rotation stopper and the damper are made of an elastic material. (3) The anti-vibration device for a brush cutter as set forth in claim 1 of the utility model registration claim, wherein the detent has a substantially rectangular shape with slightly bulged corners. (4) The damper can be a single or multiple annular damper,
Alternatively, the vibration isolating device for a brush cutter according to claim 1, which is formed from a coil spring-like unit.