JPS643634B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a vibration-proof handle device suitable for a handle of a vibrating tool or vibrating machine such as a rock drill, pitting hammer, or leg drill.

[Technical background of the invention and its problems] Harmful vibrations of the handles of vibrating tools and machines such as rock drills, pitting hammers, leg drills, and hammer drills have become an occupational health problem. Various anti-vibration handles have been proposed to solve this problem, but conventional anti-vibration handles mainly have anti-vibration rubber or springs inserted between the tool body and the handle. We are trying to improve the vibration isolation effect of the handle by lowering the natural frequency of the handle system rather than the vibration frequency.
However, in this method, in order to lower the natural frequency of the handle system in order to enhance the vibration isolation effect, it is necessary to increase the weight of the handle or use a soft anti-vibration rubber or spring with a small elastic modulus. Therefore, it is not possible to simultaneously satisfy both the requirements for light weight and operability (strength of the waist) for this type of handle.

[Object of the Invention] The present invention has been devised to effectively solve the above-mentioned conventional problems. An object of the present invention is to provide a vibration-isolating handle device that can sufficiently isolate a grip member, which is a handle portion, from harmful vibrations of a vibrating tool, etc., and that can achieve waist strength and weight reduction that are substantially similar to rigid body support. It's about doing.

[Summary of the Invention] In order to achieve the above object, the present invention is configured as follows. That is, a connecting member attached to the vibration source via a first elastic member such as rubber, a cylindrical grip member attached to the connecting member via a second elastic member such as rubber, and The gripping member includes a mass body provided in the gripping member, and an impact massing body provided within the gripping member so as to be able to collide with the inner wall surface of the gripping member.

[Embodiments of the Invention] Examples of the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a tube body attached to a vibration source such as a rock drill, and inside the tube body 1 is a first elastic member 2 made of cylindrical rubber as shown in FIG.
is inserted and fixed by baking. Nut bodies 3, 3 are embedded and fixed in the first elastic member 2 along the axis from both end faces thereof. nut body 3
has a cylindrical shape with a bottom, and has a female thread on its inner peripheral surface, so that the male threaded base end 4a of the rod-shaped connecting member 4 shown in FIG. It's getting old. The distal end portion 4b of the connecting member 4 is connected to a second rubber member filled in the proximal end side of the cylindrical grip member 5.
It is embedded in the elastic member 6 of. Also, to prevent the tip portion 4b from falling off the second elastic member 6,
A flange 4c is formed at the tip 4b of the connecting member 4.

A partition wall 5a is formed at the center of the grip member 5, and a mass body 7 is attached to the tip of the grip member 5 so as to cover the opening. In the hollow chamber 8 in the grip member 5 between the partition wall 5a and the mass body 7,
A substantially cylindrical impact mass 9 is provided. The radial dimension of the impact mass 9 is slightly smaller than the inner diameter of the grip member 5, and the axial dimension is also slightly smaller than the dimension between the mass 7 and the partition wall 5a, so that the impact mass 9 is arranged in the hollow chamber 8. It is provided so that it can vibrate within itself and collide with the inner wall surface of the grip member 5 and the mass body 7.

Next, the operation of this embodiment will be described.

Harmful original vibrations from a vibration source such as a rock drill are input into the pipe body 1. The original vibration input to the tube body 1 is attenuated by the first elastic member 2 and transmitted to the left and right connecting members 4, 4, respectively. The connecting member 4 vibrates in substantially the same phase as the original vibration. Further, the vibration of the connecting member 4 is transmitted to the grip member 5 via the second elastic member 6. However, a second elastic member 6 is interposed between the connecting member 4 and the proximal end of the grip member 5, and a mass body 7 for suppressing vibration or displacement and an impact mass are provided on the distal end side of the grip member 5. A body 9 is provided. Therefore, by appropriately selecting the elasticity of the second elastic member 6, the mass of the mass body 7, the impact mass body 9, or the length of the grip member 5, the grip member 5, which vibrates later than the connecting member 4, can be adjusted. The tip side vibrates at the same frequency and in an opposite phase to the connecting member 4. That is, the connecting member 4 is vibrated by the original vibration and becomes a vibration antinode, but a vibration node is formed on the tip end side of the grip member 5. Therefore, the original vibration from the vibration source is significantly reduced. The distal end side of the grip member 5, which is a substantial handle portion, hardly vibrates.

By the way, the vibration mode in which the connecting member 4 is the antinode of vibration and the tip side of the grip member 5 is the node of vibration is as follows.
Limited to a relatively narrow frequency range. However, in actual vibrating tools, due to load fluctuations, etc., a certain degree of vibration frequency fluctuation is unavoidable during use. For this reason, the vibration mode described above may not be realized, and the tip side of the grip member 5 may be vibrated. However, in the present invention, since the impact mass body 9 is provided within the grip member 5, a vibration damping effect can be obtained over a fairly wide frequency range.

That is, when the frequency of the original vibration of the vibration source changes and the tip side of the grip member 5 is excited, the impact mass body 9 in the hollow chamber 8 vibrates at a phase different from that of the grip member 5, and the impact mass The body 9 collides with the grip member 5, the partition wall 5a or the mass body 7. Due to this collision, vibrations on the tip side of the grip member 5 are suppressed or damped. Therefore, even against relatively wide frequency fluctuations of the vibration source, the tip side of the grip member 5, which is the substantial handle portion, can be effectively damped from vibration. Note that if the gap between the impact mass body 9 and the inner wall surface of the grip member 5 is made too small, the impact mass body 9 and the grip member 5 will become vibrationally integrated, resulting in vibration damping caused by the collision of the impact mass body 9. If the effect is not obtained and the gap is made too large, the frequency of collisions of the impact mass body 9 decreases, making it impossible to suppress vibrations of the grip member 5.

FIG. 4 shows the measurement results of the vibration acceleration transmitted to the conventional handle of a rock drill, and FIG. 5 shows the measurement results of the vibration acceleration transmitted to the tip side of No. 5. (Fig. 4, 5
In the figure, the units of the horizontal and vertical axes are seconds and gravitational acceleration, respectively. ) As is clear from the comparison of FIGS. 4 and 5, the strong harmful vibrations transmitted to the conventional handle are drastically reduced to extremely weak vibrations in the vibration-proof handle device of the present invention. This vibration-proofing effect is equally observed in both radial and axial vibrations of the grip member 5.

FIG. 6 shows the second vibration-proof handle device according to the present invention.
An example is shown below.

In the figure, reference numeral 10 denotes an attachment plate that is attached to a vibration source such as a leg drill with bolts or the like, and tube bodies 11, 11 are attached to both ends of the bent attachment plate 10, respectively. Inside the tube body 11 is a first elastic member 12 made of rubber.
is filled. A cylindrical grip member 13 with a slightly enlarged diameter at the center is provided between the tubes 11 and 11.
It is installed coaxially with the Both ends of the grip member 13 are filled with second elastic members 14, 14 made of rubber. The grip member 13 is supported by a rod-shaped connecting member 15 that is stretched between the second elastic member 14 and the first elastic member 12 . The inner end of the connecting member 15 is embedded and fixed in the second elastic member 14 . Further, the outer end portion of the connecting member 15 is provided to pass through the first elastic member 12,
A fixing nut 16 is attached to the outer end. The first elastic member 1 through which the connecting member 15 passes
A sleeve 19 is provided in the penetrating portion 2.
An annular mass body 1 is provided on the outer periphery of both ends of the grip member 13.
7 is installed. The grip member 13 also has a partition wall 1 to define a hollow chamber in the center thereof.
3a and 13a are formed, and an impact mass body 18 whose diameter is slightly smaller than the inner wall surface of the grip member 13 is provided in the hollow chamber so that it can collide with the inner wall surface of the grip member 13.

The original vibration of the vibration source is the mounting plate 10 and the tube body 11.
The signal is then further attenuated by the first elastic member 12 and transmitted to the connecting member 15 . The connecting member 15 vibrates at substantially the same phase and frequency as the original vibration, although the amplitude is smaller than the original vibration. The connecting member 15 vibrates relatively violently, but due to the presence of the second elastic member 14 and the impact mass body 18, the central portion of the grip member 13 lags behind the connecting member 15 and has an opposite phase, forming nodes of vibration. . In this way, the central portion of the grip member 13, which is essentially the handle portion, hardly vibrates, and sufficient vibration isolation is achieved. In addition, in this embodiment, the mass body 1
7 extends from the tip of the connecting member 15 to the second elastic member 1
It is considered that the grip member 13 acts as an inertial mass that suppresses vibrations transmitted to the end portion of the grip member 13 via the grip member 13. The vibration suppression effect due to the collision of the impact mass body 18 is similar to that of the above embodiment.

FIG. 7 shows the measurement results of vibration acceleration transmitted to a conventional handle attached to a leg drill. On the other hand, Fig. 8 shows this second leg drill in the same leg drill.
The measurement results of the vibration acceleration transmitted to the central part of the grip member 13 when the vibration-proof handle device of the example is mounted are shown. An extremely good vibration damping effect was confirmed in this example as well.

Next, FIG. 9 shows a third embodiment of the present invention. In the figure, reference numeral 20 denotes a bottomed cylindrical attachment body that is attached to a vibration source such as a pitching hammer.
The mounting body 20 also serves as a supply unit that supplies compressed air for operation to the vibration-isolating tool main body, which is a vibration source, and a tube 21 that supplies pressurized air to the mounting body 20 is attached to the side wall of the mounting body 20. There is. The tube 21 is curved to form a handle;
A rubber elastic member 22 is attached to the tip of the tube 21.
A cylindrical grip member 23 is attached via. An impact mass body 2 is disposed on the distal end side of the grip member 23.
4 are provided so that they can collide. Also, grip member 2
A connecting portion 25 for attaching a hose for supplying pressurized air is formed at the tip of 3. Also, the mounting body 2
The tube 21 between the grip member 23 and the handle member 23 is provided with an on-off valve 26 for opening and closing the pressure passage. The on-off valve 26 mainly includes a valve body 27 having a through hole, a spring 29 that presses and supports the valve body 27 against a valve box 28, and a lever 30 for operating the valve body 27. Note that the impact mass body 24 is formed with a through hole through which pressurized air passes. The original vibration of the vibration source is transmitted from the mounting body 20 to the tube 21, but due to the presence of the elastic member 22 and the impact mass body 24, a vibration node is formed on the tip side of the grip member 23, which is essentially the handle portion. Anti-vibration is achieved. Furthermore, the effect of suppressing vibrations caused by collisions of the impact mass body 24 can also be obtained.

FIG. 10 shows the measurement results of vibration acceleration transmitted to a conventional handle attached to a pitching hammer. On the other hand, FIG. 11 shows the measurement results of the vibration acceleration transmitted to the tip side of the grip member 23 when the vibration-proof handle device of the third embodiment is attached to the same pitching hammer. It was confirmed that this example also had an excellent anti-vibration effect.

In the above embodiments, the impact mass bodies were all integrated, but they may be divided into, for example, a plurality of washers. If this is done, collisions between the wires will occur, making the collisions random, and the vibration damping effect will be further improved.

[Effects of the Invention] In summary, according to the present invention, there is an extremely good vibration damping effect against vibrations in a fairly wide range of frequencies, and furthermore, the waist strength is substantially close to that of a rigid body support, and the size and weight are reduced. It is possible to achieve excellent effects such as easy operation and high operability.

[Brief explanation of the drawing]

FIG. 1 shows the first vibration-proof handle device according to the present invention.
FIG. 2 is a longitudinal cross-sectional view of the inside of the tube which is the attachment part of the handle device to the vibration source;
Figure 3 is an enlarged vertical sectional view of the grip part in Figure 1;
The figure is a graph showing the vibration acceleration transmitted to the conventional handle of a rock drill, and FIG. 5 is a graph showing the vibration acceleration transmitted to the conventional handle of a rock drill. 6 is a partially cutaway front view of the second embodiment of the present invention, and FIG. 7 is a graph showing the vibration acceleration transmitted to the conventional handle of a leg drill.
FIG. 8 is a graph showing the vibration acceleration transmitted to the central part of the grip member when the vibration-proof handle device of the second embodiment of the present invention is attached to the same leg drill;
FIG. 9 is a partially cutaway front view showing a third embodiment of the present invention, FIG. 10 is a graph showing vibration acceleration transmitted to a conventional handle of a pitching hammer, and FIG.
FIG. 1 is a graph showing the vibration acceleration transmitted to the tip of the grip member when the vibration-proof handle device of the third embodiment of the present invention is attached to the same pitching hammer. In the figure, 2, 6, 12, 14, 23 are elastic members,
4 and 15 are connecting members, 5, 13 and 23 are grip members, 7 and 17 are mass bodies, and 9, 18 and 24 are impact mass bodies.

Claims (1)

[Claims] 1. A connecting member attached to the vibration source via a first elastic member such as rubber, a cylindrical grip member attached to the connecting member via a second elastic member such as rubber, and the grip. a mass body provided on the member;
A vibration-proof handle device comprising: an impact mass body provided in a grip member so as to be able to collide with an inner wall surface of the grip member.