JPS5815686A - Vibration-proof handle device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] This invention relates to a vibration-proof handle device, and in particular, it is attached to a vibrating machine such as a hand-held power tool such as a brush cutter, a compressed air tool, or a motorcycle, so that the vibrations generated in the machine can be prevented. The present invention relates to an anti-vibration handle device that can sufficiently prevent vibrations from being transmitted to a grip member that is a handle part, improve the operability of a vibrating machine, and can be made small and lightweight.

Conventionally, as a vibration-proofing measure for hand-held tools such as brush cutters and vibrating machines such as motorcycles, measures have been taken to interpose a vibration-isolating rubber between the vibration source and the handle of the vibrating machine, or to install a vibration absorber. I was planning to set one up.

However, when anti-vibration rubber is used, a force proportional to the vibration speed is transmitted to the handle, making it difficult to block harmful vibrations that can cause occupational accidents such as white wax, and also making it difficult to operate the handle. becomes soft, causing the vibrating tool to wobble. In the case of TFC and vibration absorbers, in order to increase the vibration isolation effect, the weight of the vibration absorber must be increased, which poses a problem in that the workability and operability of the vibrating tool decreases.

This invention has been devised to effectively solve the above-mentioned conventional problems.

The purpose of this invention is to sufficiently isolate harmful vibrations generated in the handles of hand-held vibrating tools such as brush cutters and vibrating machines such as motorcycles, and to improve the operability of vibrating machines. It is an object of the present invention to provide a vibration-proof handle device which can be improved, and which can be made small and lightweight.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a vibration source that generates harmful vibrations, such as the main body or casing of a brush cutter, electric grinder, or the like, or the body of a motorcycle. A rod-shaped body 2 made of steel and having a circular cross section is provided extending from the vibration source 1 in a cantilever shape. The fixed end of the rod-shaped body 2 is provided with a male thread 2a, and the fixed end of the rod-shaped body 2 is passed through a screw hole of a connecting part 3 fixed to the vibration source 1 by welding or the like. , by screwing the tip of the fixed end into the vibration source 1.
Fixed.

A first mass body 4 is provided at the free end of the rod-shaped body 2 . The first mass body 4 is provided with a screw hole that can be screwed into a male screw 2b provided at the end of the rod-shaped body 2, and by feeding the screw along the male screw 2b. , the first mass body 4 can be moved in the axial direction of the rod-shaped body 2.

Further, a rod-shaped body 2 is provided between the first mass body 4 and the connecting portion 3.
A cylindrical grip member 5 is provided so as to be spaced from and cover the outside of the grip member. A coil spring 6 is provided between the connecting portion 3 and the left end portion 5a of the grip member 5, and a coil spring 7 is provided between the first mass body 4 and the right end portion 5b of the grip member 5 (respectively). The coil springs 6 and 7 have the same strength, and the grip! 11 member 5 is supported by the elastic force of the coil springs 6 and 7, and the grip member 5 is connected to the rod-shaped body 2 and the first mass. The body 4 and the connecting part 3 are not in direct contact with each other, and the vibrations are transmitted and received between them and the grip member 5 by the coil spring 6.7.
done through. In addition, 3 a + 4 B.

5c and 5d are spring holders.

On the outer periphery of the left end 5a and right end 5b of the grip member 5,
A second mass having equal mass and having an annular shape 8.
9 are provided respectively. In order to allow the second mass body 8.9 to slide along the axial direction of the grip member 5, external threads 5e,
5f is applied, and the inner circumferential surface vc of the second mass body 8.9 has a female thread 9a that is threadedly engaged with the male threads 5e and 5f.
, 9a are applied, respectively. Further, each of the second mass bodies 8.9 is provided with set screws 10°11 for fixing them to the grip member 5vc.

Next, the operation of this embodiment will be described.

The harmful original vibration from the vibration source 1 is transmitted to the connecting part 3 and the rod-shaped body 2.
is transmitted to the fixed end of the vibration source, and vibrates with the same phase and frequency as the original vibration. Vibration energy (kinetic energy) transmitted from the vibration source 1 to the connecting portion 3 and the fixed end of the rod-shaped body 2 is divided into two and transmitted via the coil spring 6 and the rod-shaped body 2. However, since the rod-shaped body 2 has considerably greater rigidity than the coil spring 6, most of the vibration energy is transmitted to the first mass body 4 via the rod-shaped body 2, and the remaining part of the vibration energy is transmitted to the first mass body 4. It is transmitted to the left end portion 5a of the grip member 5 via the coil spring 6.

The first mass body 4 is vibrated by the vibration transmitted via the rod-shaped body 2 in substantially the same phase and frequency as the original vibration.

The vibrations of the first mass body 4 are transmitted to the right end portion 5b of the grip member 5 via the coil spring 7 in a significantly damped manner, and further transmitted to the second mass body 9. Further, the vibration transmitted to the left end portion 5a via the coil spring 6f is transmitted to the second mass body 8.

By the way, here, when the second mass bodies 8.9 are respectively screwed and installed at appropriate positions between the left end 5a and the right end 5b, the second mass bodies 9 and the grip member 5 in the vicinity , vibration nodes can be formed, and the amplitude of the second mass body 9 can be made extremely small.

This will be explained using the schematic diagram shown in FIG. In the figure, 20 is an elongated rod made of metal or the like, and weights 21 and 22 are attached to the center and tip of the rod 20, respectively. When the base end 2oat of this rod 20 is vibrated left and right, this vibration is transmitted to the weight 21 through the rod 201, and the weight v
22, and the weights 21 and 22 vibrate.

However, if the mass of the weights 21 and 22, the position of the weights 21 and 22 on the rod 20, and the elastic modulus and thickness of the rod 20 are appropriately selected, the weight v22 will be as shown in the figure.
It is possible to create a state of vibration in which there is almost no vibration. That is, the weight 21 vibrates at the same frequency and phase as the base end 20a, and the weight 22 vibrates later than the vibration of the weight 21.
vibrates at the same frequency and in opposite phase to the heavy v21,
The vibrations transmitted from the to the weight 22 to the weight 22 are significantly reduced, and the weight 22 vibrates with extremely small amplitude.

Comparing the vibration system shown in FIG. 2 with the vibration system of the above embodiment, it is found that the weight 21 is attached to the first mass body 4, and the weight! 1122 corresponds to the second mass body 9, and the base end 20.
It is considered that the portion from the weight 21 to the weight 21 corresponds to the rod-shaped body 2, and the portion from the weight v21 to the weight v22 of the rod 20 corresponds to the coil spring 7.

That is, most of the vibration energy of the original vibration from the vibration source 1 is transmitted to the first mass body 4 via the rod-shaped body 2, and the first mass body 4 is excited. At this time, the vibration energy of the original vibration is mainly dissipated as thermal energy (heat generation) generated by internal strain in the rod-shaped body 2, the first mass body 4, and the fill spring 7.

The second mass body 9 vibrates at almost the opposite phase and the same frequency as the first mass body 4, and the first mass body 9 and the grip member 51C in its vicinity have vibration nodes. As a result, the second mass 9 oscillates with a very small amplitude. On the other hand, the remaining small part of the vibration energy of the original vibration is transmitted to the second mass body 8 and the left end portion 5a via the coil spring 6, but this vibration is suppressed by the mass of the second mass body 8. Significantly attenuated.

Therefore, the original vibration from the vibration source 1 is hardly transmitted to the grip portion 5gvc of the swinging member 5 between the second mass bodies 8.9, and is transmitted to the operator's hand via the grip portion 5g. The transmitted vibrations are significantly weaker than the original vibrations.

Further, since a soft elastic member such as vibration-proof rubber is not used, a vibrating tool such as an electric drill does not wobble, and the i-tool can be operated accurately. Furthermore, since a method of forming a vibration node in the device and attaching a grip to this node is adopted, the device can be made much lighter and smaller than conventional devices.

In the above embodiment, in order to form a vibration node in the second mass body 9 or the grip member 5 in the vicinity thereof, the second
However, the first or second mass body 4.9 is formed by a plurality of divided pieces, and the masses are adjusted by attaching and detaching the divided pieces [7]. It may be possible to adjust by increasing or decreasing the amount. In addition, since the second mass body 8tri suppresses the vibration from the coil spring 6 by its mass, the spring receiver 5 which transmits the vibration from the coil spring 6 to the grip member 5 as shown in FIG.
When installed near the outside C, the vibration suppression effect is great. In addition,
In the embodiment described above, the rod-shaped body 2 is made of a round rod having the same diameter over its entire length, but in order to increase the flexibility of the free end side of the rod-shaped body 2 and violently vibrate the mass body 4 of the child 1, in order to dissipate energy. , as shown in FIG. 3, it is formed into a tapered shape that gradually decreases in diameter toward the free end, or as shown in FIG. You may change it to something else. Furthermore, a plate spring or the like may be used instead of the coil (spring 6.7).Furthermore, the connecting portion 3 may be omitted and only the rod-shaped body 2 may be connected to the vibration source 1.

Alternatively, five gripping members may be extended to apply pressure to the outside of the first mass body 4.

Figures 5 to 7 show vibration experiments carried out by attaching the above-mentioned embodiment of the present invention and the conventional marking machine to a commercially available brush cutter. The results are shown.

In FIG. 5, the acceleration of the original vibration of the vibration source of the handle mounting section is shown. Furthermore, Fig. 6 shows the acceleration of the vibration transmitted to the grip 9 of the conventional standard nozzle.
FIG. 7 shows the acceleration of vibrations transmitted to the handle of the nozzle of the present invention. In Figures 5, 6, and 7, the horizontal axis is time and the vertical axis is acceleration.
g is the gravitational acceleration. As shown in the figure, the /・ of the present invention
The vibration of the original vibration is significantly attenuated by the handle, and the remarkable vibration-proofing effect of the present invention is recognized. Note that although Figures 5, 6, and 7 show the acceleration of vibration in the vertical direction,
The handle of the present invention can be used in the left-right direction (the radial direction of the grip member 5 and the horizontal direction) and the back-and-forth direction (the axial direction of the rod-shaped body 2).
It has been confirmed that a similar vibration damping effect can be obtained for vibrations in the three directions, and an effective vibration damping effect can also be obtained for original vibrations in which vibrations in these three directions are complicatedly overlapped.

As is clear from the above explanation, according to the present invention, it is possible to completely prevent harmful vibrations that cause white wax disease, etc.
Furthermore, since no vibration-proofing rubber or the like is used, the operability of the vibrating tool is improved, and excellent effects such as being lightweight and compact can be exhibited.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the device according to the present invention;
FIG. 2 is a schematic diagram for explaining the anti-vibration effect of the present invention, FIG. 3 is a front view showing another example of the rod-shaped body, FIG. 4 is a front view showing another example of the rod-shaped body, and FIG. The figures are graphs showing the acceleration of the original vibration at the handle attachment part of a commercially available brush cutter. Figures 6 and 7 are graphs showing the conventional standard handle and the inventive handle attached to the same brush cutter. 3 is a graph showing the acceleration of vibration transmitted to the grip portion of each handle when the vehicle is rotated. In the figure, 1 is a vibration source, 2 is a rod-shaped body, 4 is a first mass body, 5
is the grip V member, 6.7 is the elastic member (coil spring), 8.9
is the second mass body. Patent applicant Makoto Minamidate Patent attorney Nobuo Kinutani

Claims (1)

[Claims] a rod-shaped body connected to the vibration # and extended therefrom; a first mass body provided at the free end of the rod-shaped body; and a first mass body provided so as to cover the rod-shaped body while being spaced apart from the rod-shaped body. a gripping member; a resilient member interposed between the gripping member and the first mass body and the vibration source to resiliently support the gripping member;
A vibration-proof handle device comprising: second mass bodies provided at both ends of the grip member.