JPS6017669B2 - Vibration isolation type handle device - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a vibration-isolating handle device, which is particularly attached to hand-held vibrating machines such as tie tampers and hammer drills, and is capable of sufficiently blocking harmful vibrations generated in these machines from being transmitted to a grip member serving as a handle. The present invention relates to a vibration-isolating type handle device that can be used. Conventionally, anti-vibration measures for hand-held vibrating machines such as tie tampers and electric drills have mainly involved placing an elastic or elastic member such as anti-vibration rubber or a spring between the vibration source of the vibrating machine and the handle. The idea was to insulate vibrations. However, with this method, it is not possible to expect a vibration insulating effect against strong vibrations at relatively high frequencies, such as with titanpa, and it is difficult to prevent harmful vibrations that cause vibration disasters such as white wax. Ta. Furthermore, even if a certain degree of vibration insulation effect could be achieved, the presence of vibration-proof rubber, springs with small spring constants, etc. made the operation soft, causing the vibrating machine to wobble and prevent accurate operation. . The present invention has been devised to effectively solve the above-mentioned conventional problems. An object of the present invention is to almost completely block harmful vibrations even though the device is substantially rigidly connected to a vibrating machine such as a tamper or a hammer drill. First, in order to facilitate understanding of the vibration isolation effect of the device according to the present invention, before explaining the embodiments of the present invention, the vibration isolation principle of the present invention will be compared with the vibration isolation principle of a conventional vibration isolator. I will explain. FIG. 1 shows a principle diagram of the vibration system of a conventional vibration isolator. In the figure, 1 is a vibration source that vibrates in the vertical direction with a frequency and an amplitude of X. A single-beam spring 2 having a spring constant K is connected to the vibration source 1, and a handle 3 having a mass M is provided on a free-wheeling portion of the spring 2. When the vibration source 1 vibrates, this vibration is transmitted to the handle 3 via the spring 2, and the handle 3 is vibrated. If the amplitude of the handle 3 is represented by x, then the amplitude ratio x x i is expressed as a function of frequency by the following equation. Receiving =;
Kosango...

[1} Here, the cape is in front of the branch and is the natural frequency of the handle 3. {The vibration response curve of equation 11 is curve a in FIG. Third
The key axis of the graph in the figure is the ratio (frequency ratio) between the excitation frequency and the natural frequency n, and the vertical koji is the amplitude ratio. ○Rn As is clear from curve a, unless ^ is considerably larger than 1, the amplitude ratio ×ノ× will not become small. In other words, with conventional vibration isolators, vibration damping effects can only be obtained when the excitation frequency is quite high. In order to have a vibration damping effect, it is necessary to reduce the natural frequency side by 4 inches. However, if K is made small, the operation of the handle 3 relative to the vibration source becomes soft, causing the vibration source to wobble, and M
If the value is increased, the bag layer will become heavier. Therefore, it can be seen that it is impossible to combine vibration isolation and operability with a secondary vibration isolator. Next, FIG. 2 shows a diagram of the principle of the vibration system of the present invention. The vibration system of the present invention has an impact damper type weight 4 of mass m attached to a spring 2 of a conventional vibration isolator shown in the diagram. It consists of a casing and a vibrating mass body 7 supported within the casing 5 via a spring 6. is structured so that it vibrates violently when the casing 5 vibrates above a certain frequency and collides with the inner wall surface of the casing S. In the vibration system of the present invention shown in FIG. 2, the mass M
The amplitude ratio X/X between the amplitude X of the handle 3 and the amplitude Xi at the vibration point is as follows. Here,
...(2) Q. The petitioner was Wakiba, Misaki, and the petitioner was Sakito. K' is the spring constant of spring 2 from the excitation point to the weight turtle's weight point, and Q' is the spring constant ratio of &ku1. Also, the mass ratio between the mass M of the handle 3 and the mass m of the weight turtle is 1 (M>m). The vibration response curve of Equation 21 above becomes curve b in Figure 3 when Q = 0.55 and Q = 2.5. As is clear from the comparison between curve a and curve b, input =
It can be seen that on the higher frequency side than the resonance point ^2 near 3, the vibration isolation characteristic of curve b is extremely superior to that of curve a. For example, at ~ input ilo, the amplitude ratio of curve A is about V10O, while curve B is about 1'10
The amplitude has decreased to 1'1000. By the way, in the case of a single beam type spring, the spring constant K is
13 (E; Young's modulus, leather; second moment of area, force; length of spring), so mosquito = 0. 55 (ra(0.83)3), the attachment point of the weight 4 corresponds to a point 082i from the vibration point. On the other hand, as a result of numerical calculations to find the optimal value to make the resonance point 2 as low frequency as possible, it was found that the target value should be about 0.5 < Q < 0.5 f 2 < broadside 3, respectively. Served. In other words, ``(1'2 to 3 of the mass M of the handle 3
A weight 4 having a mass of about Q. If it is attached to the top of a nail, a vibration response characteristic similar to the curve in Figure 3 can be obtained.However, even if a weight turtle is attached, a peak at the second resonance point ^2 appears on the high frequency side, and the vibration source is The frequency of the vine may fluctuate and enter the area near the resonance point X2, so countermeasures are required. It will vibrate violently at point C2.
Therefore, near the resonance point 2, the crab turtle's vibratory mass body 7 vibrates violently, and the vibratory mass body 7 repeatedly collides with the casing 5. Due to the vibration, the vibration energy from the vibration source 1 is converted into thermal energy (heat generation) and absorbed, and the peak of the vibration response curve b at the resonance point ^2 is removed.Furthermore,
At a frequency above the resonance point ^2, the amplitude of the weight 4 becomes small, and the casing 5 of the weight 4 and the vibrating mass body T vibrate as one body, becoming almost equal to the curve b in Fig. 3, and eventually the amplitude of the weight 4 becomes small. Excellent vibration isolation characteristics as shown in Figure 4 can be obtained. The present invention is described below as a vibrating machine for compacting gravel under sleepers for track maintenance work. An example applied to Titanbar is shown. In FIG. 5, reference numeral 8 denotes a tamping plate for compacting gravel by its vibrations, and the tamping plate 8 is attached to a motor casing 10' of a drive motor 9 that applies vibrations to the tamping plate 8. The motor casing turtle 0', which is the opposite example to the tamping plate 8, has leaf springs 1 and 2 attached, respectively.
The motor casing mounting base of the leaf spring is constituted by a plurality of leaf springs, and the leaf spring 12 is connected to the motor casing via a pin 13. In addition, the leaf springs 11, 2 are appropriately curved as shown in the figure in order to damp vibrations from the drive motor 9, and the tips of the leaf springs 11, 12 are on both ends of the hakama body turtle 4. It is connected to the bracket 16 and the wing 6 provided on the plate spring 11 through pins 119 and 38, respectively.A grip member 19, which is a handle part, is attached to one end of the hollow body 14. A steel casing 2 is located near the pin blade 7.
0 is set. As shown in an enlarged view in FIG. 6, the casing 20' has a cylindrical body, and its both ends are covered with cover parts 28a, 28a. 21 is provided, and the mass body 21 is supported by the pressing force of coils 22, 22, which are interposed in a compressed state between both ends of the mass body 21 and the lids 20a, 2Qa, respectively. Spring receiving parts 21 are provided at both ends of the hole.
a, 2 turtles a also face these diamond parts 28a, 20a
Spring receiving portions 28b, 28b are also respectively formed therein. The casing 20 and the vibrating mass body 21 are separated by a small gap, but when the casing 20 vibrates above a certain frequency, the vibrating mass body 21 vibrates overcoming the pressing force of the coil spring 22, and the casing 20 so that it can collide with the inner wall surface 20c of 20. Further, on the outside of the casing 20, mounting fittings 23, 23 for attaching it to the leaf spring 11 are provided. 24, the leaf spring 11 is sandwiched between the mounting fittings 23, 23 and the vertical mounting plate 25, and the casing 20 is assembled.
is fixed to the leaf spring 11. Next, the operation of this embodiment will be described. The tamping plate 8 vibrates violently due to the operation of the drive motor 9, and the gravel is compacted by inserting the vibrating tamping plate 8 into the gravel. The vibration energy is transmitted to the shield body 14 via the springs 1 and 12, but since the base of the leaf spring 11 is attached to the motor casing 1W by a plurality of leaf springs, most of the vibration energy from the drive motor 9 is It is transmitted to the leaf spring 11, and the tip of the leaf spring 12 is
There is almost no vibration, and the shield body 14 and the grip member 19 are attached to the pin 1.
It will be vibrated up and down using the tip of the body g4 as a fulcrum. By the way, here we will discuss the ``vibration system of this embodiment and the second
Comparing the vibration system shown in the figure, the drive motor 9 corresponds to the vibration source, the blades of the leaf spring 1 correspond to the spring 2, the grip member 19 corresponds to the handle 3, and the casing 2
It can be seen that the vibrating mass body 23, the coil spring 22, etc. correspond to the weight 4. Therefore, the total mass of the casing 28, the vibratory mass body 21, the coil spring 22, etc. If the mounting position is set to the optimum value in the above-mentioned theoretical explanation, vibration isolation characteristics as shown by curve b in Fig. 3 can be obtained. The vibration energy that corresponds to the resonant frequency of the grip member 19 among the original vibrations from the turbulent motor 9 is transmitted to the vibrating mass body 21 by the impact force caused by the collision between the vibrating mass body 21 and the casing 28. and casing 201 heat energy (
dissipated as heat generation). Therefore, harmful original vibrations are not transmitted to the connecting part 19, and ultimately, extremely excellent vibration isolation characteristics as shown in FIG. 4 can be obtained. In the above embodiment, the vibrating mass body 21 has a cylindrical shape, but is not limited to this, and may have any shape as long as it has a large density of rigid bodies. The shape is also the vibrating mass body 2
The shape may be changed in any way depending on the shape of the opening, and the opening may be appropriately provided instead of being closed. Also coil spring 2
You are free to change 2 to a leaf spring. Below, the results of a vibration experiment of the present invention, conducted using the tie tamper shown in FIG. 5, are shown in FIGS. 7A and 7B. FIG. 7A shows the vibration acceleration transmitted to the gripping material 19 when nothing is attached to the leaf spring 11 as in the conventional case,
In addition, Figure 7 B' shows the vibration acceleration when the casing 20 etc. are attached as shown in Figure 5. It has been confirmed that the original vibration can be almost completely blocked.As is clear from the above explanation, according to the present invention, even though it is substantially rigidly connected to a vibrating machine such as a tie tamper or a hammer drill, ``Harmful vibrations can be almost completely blocked, and the transmission to the grip section, which is the handle, is extremely weak, making it possible to reliably prevent vibration disasters such as white wax.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram showing the vibration system of the secondary vibration isolator, Fig. 2 is a principle diagram showing the vibration system of the present invention, and Fig. 3 is the vibration response curve of the secondary vibration isolator and its integrated components. A graph showing a vibration response curve when the weight of an object is added, FIG. 4 is a graph showing a vibration response curve of a vibration system equivalent to the present invention, and FIG. 5 is a graph showing a vibration response curve of a vibration system equivalent to the present invention. FIG. FIG. 6 is an enlarged cross-sectional view of the casing section shown in FIG. 5 in the direction of arrows, and FIG. 1 is a graph showing the measurement results measured in the case of the slave and in the case of the embodiment of the invention this evening. 2 is a spring, 11 is a leaf spring), 3 and 19 are binding members (3 is a handle), and 69028' is a casing, T
, 2 rivers and vibrating mass bodies ~ 6 and 22 are rock-starting members (6 is a spring, 2 is a coil). Figure 1 Figure 2 Figure 7 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1 a connecting member connected to and extending from the vibration source;
a grip member provided at the tip of the connecting member; a casing attached to the connecting member between the grip member and the vibration source; It has a vibrating mass body supported via a resilient member so as to be able to come into contact with the inner wall surface of the casing, and the mounting position of the casing has a spring constant that is approximately twice the spring constant of the entire length of the connecting member from the vibration source. A vibration-isolating type handle device, characterized in that the mass of the casing, the vibrating mass body, and the elastic member is set to 1/2 to 1/3 of the mass of the grip member.