JP2012229583A - Sound insulation device of drilling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound insulation device of a drilling machine, which can reduce noises from a drilling rod section of a drilling unit while maintaining operability of the drilling machine.SOLUTION: A sound insulation device 30 comprises double cornices which cover an overall-length portion of a drilling rod 7 of a drilling unit 3 and which are longitudinally expanded/contracted, and the double cornices are disposed separately from each other in a radial direction so as to have an air space therebetween.

Description

  The present invention relates to a sound insulation device used in a drilling machine including a drilling device.

The drilling machine generates a large amount of noise from the part of the drilling rod (the sound pressure level is very high and contains a lot of high-frequency sound). Therefore, it is conceivable to shield a site where noise occurs. However, although shielding is effective in reducing the sound pressure level (particularly in the high frequency range), the low frequency reaches far away because the distance attenuation is smaller than the high frequency. Therefore, depending on the shielding method, there is a problem that a complaint is made because noise (working sound) reaches far away residents.
Therefore, for example, Patent Document 1 proposes a technique for reducing noise by shielding the entire drilling device of a drilling machine.

Special Table 2002-533597

However, as in the technique described in Patent Document 1, it is preferable to shield the entire drilling device because the operability of the drilling device is reduced for the operator although noise can be reduced. That's not true.
Therefore, the present invention has been made paying attention to such problems, and can reduce noise from the portion of the drilling rod of the drilling device while maintaining the operability of the drilling device. It aims at providing the sound insulation apparatus of a drilling machine.

In order to solve the above-mentioned problems, the present invention is a sound insulation device used in a drilling machine provided with a drilling device, comprising a double bellows covering the drilling rod of the drilling device over its entire length. The double bellows are characterized by being spaced apart in the radial direction so as to expand and contract along the longitudinal direction of the drill rod and to have an air layer therebetween.
According to the sound insulation device for a drilling machine according to the present invention, the two bellows are mounted over the entire length of the drilling rod so as to cover only the part of the drilling rod of the drilling device. The operability is not reduced. Since these two bellows expand and contract in the longitudinal direction, the rod can be easily replaced.

And, according to this sound insulation device, since it is covered with a double bellows having an air layer between them, it is of course compared with a double bellows structure as compared with a structure covered with a single bellows. However, it is difficult to pass noise, and noise can be effectively reduced.
Here, in the sound insulation device for a drilling machine according to the present invention, it is desired to reduce the radial thickness of the air layer between the two bellows so that the reflected waves of noise interfere between the two bellows and cancel each other. It is preferable to set according to the frequency band of noise. With such a configuration, the reflected waves of the noise interfere with each other between the two bellows and cancel each other out, so that the noise of the target frequency can be effectively shielded.

  As described above, according to the sound insulation device for a drilling machine according to the present invention, it is possible to reduce noise from the part of the drilling rod of the drilling apparatus while maintaining the operability of the drilling machine.

It is explanatory drawing of the crawler drill as one Embodiment of a drilling machine provided with the sound insulation apparatus which concerns on this invention. FIG. 2 is an enlarged view of a main part (A part) of FIG. It is a graph which shows the relationship between the frequency of the noise of the drilling machine and the sound pressure. In the same figure, a microphone is placed at a position 64 m away from the drilling rod, without a sound insulation device (standard), and with a sound insulation device (bellows 1 The graph of the data measured when the sound insulation device is provided (double bellows) is shown. It is a graph which shows the relationship between the frequency of the noise of a drilling machine and the sound pressure. In the same figure, each data measured when there is no sound insulation device (standard) and with a sound insulation device (double bellows) in FIG. The graph of the data which multiplied A characteristic is shown, respectively.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate.
As shown in FIG. 1, the crawler drill 1 has a main body 2 and a drilling device 3 connected to the main body 2 via a boom 25. The main body 2 includes a cabin 5 and an engine room 4 behind the cabin 5, and a crawler type traveling device 6 is provided at a lower portion of the main body 2.
The drilling device 3 supports and guides the drill rod 7 to which a drill for drilling is attached at the tip, a drifter 8 that rotates and blows the drill rod 7, and feeds the drill rod 7. And a centralizer 22 that is attached to the vicinity of the lower end of the guide shell 10 and supports and guides the lower side of the drill rod 7. A hood mechanism 21 is provided at the lower portion of the centralizer 22, and a hood pad 23 is attached to the lower end side of the guide shell 10. A plurality of claws projecting downward are provided at the lower end portion of the hood pad 23. 24 is provided.

  Further, the drilling device 3 is provided with a slide cylinder 20 that slides the guide shell 10 in the vertical direction, and an intermediate portion of the slide cylinder 20 is connected to the main body 2 by a boom 25. The boom 25 can be swung in the front-rear direction by a lift cylinder 26 disposed below the boom 25, and the slide cylinder 20 can be swung in a front-rear direction by a lift cylinder 27 disposed between the boom 25. It has become. The lift cylinders 26 and 27 are appropriately driven to adjust the tilt angle of the drilling device 3 in the front-rear direction. A swing cylinder (not shown) is interposed between the boom 25 and the slide cylinder 20, and by driving this swing cylinder, the tilt angle of the drilling device 3 in the left-right direction can be adjusted. It has become.

Here, a sound insulation device 30 is attached to the drill rod 7 of the drill device 3.
Specifically, the sound insulation device 30 is disposed over the entire length of the drill rod 7 as shown in FIG. As shown in an enlarged view in FIG. 2, it has a cylindrical first bellows 32 and a second bellows 34 that expand and contract along the longitudinal direction of the drill rod 7. The first bellows 32 is arranged coaxially with the air rod D1 so as to surround the entire circumference of the drill rod 7. The second bellows 34 is arranged coaxially with the air layer D2 so as to surround the entire circumference of the first bellows 32. The two bellows 32 and 34 are fixed to each other by an upper fixed ring 36 and a lower fixed ring 38 shown in FIG. 1 so as to maintain a distance between the air layer D1 and the air layer D2. The hole device 3 is supported by the upper and lower stationary rings 36 and 38.

Here, in the example of this embodiment, the thickness of the air layer D2 between the two bellows 32 and 34 is reduced so that the reflected wave of noise interferes between the two bellows 32 and 34 and cancels out. It is set according to the frequency band of the noise you want. Thereby, the reflected wave of noise interferes between the two bellows 32 and 34 and cancels out.
For example, when it is desired to lower the sound pressure of 1500 Hz or higher, the speed of sound: 340 m / s = frequency: 1500 Hz × wavelength, whereby the wavelength = 0.226 m. Therefore, from the wavelength /4=0.056 m = D2, this is set as the thickness of the air layer D2 between the bellows 32, 34. That is, in this example, the first bellows 32 (small bellows diameter): 100 mm and the second bellows 34 (large bellows diameter): 212 mm. As a result, noise frequencies of 1500 Hz, 3000 Hz, and 4500 Hz other than overtones cause the reflected waves of noise to interfere and cancel each other between the two bellows 32 and 34, effectively shielding the noise of the target frequency. It is possible to do. The intermittent work sound that can be heard in the distance includes a specific frequency (1500 Hz or higher). Therefore, for example, in order to cope with a problem that a complaint is made because noise (work sound) reaches a distant resident, it is desirable to adopt the separation dimension (D2) of the present embodiment.

Next, the operation of the drilling machine 1 and the operation and effect of the sound insulation device 30 will be described.
When drilling holes in the ground GL using the drilling machine 1 described above, first, the traveling device 6 is driven to move the main body 2 to a predetermined position, and then the cylinders 26, 27, 20 and the like are appropriately driven Then, the front and rear, left and right inclination angles of the guide shell 10 and the vertical sliding position are adjusted. Then, the guide shell 10 of the drilling device 3 is positioned by piercing the claw 24 of the food pad 23 into the ground, and the drilling position and the inclination angle are determined by the drilling rod 7. Thereafter, the drifter 8 and the feed driving device 9 are actuated to apply rotation, striking and feeding operations to the drill rod 7 to form a drill hole having a predetermined depth.

Here, in the drilling machine 1, when the sound insulation device 30 is not mounted, as shown in FIG. 3, the noise generated from the drilling rod 7 is large (see “standard” in the figure). ). However, since the drilling machine 1 includes the sound insulation device 30 that covers the part of the drilling rod 7, the noise generated from the part of the drilling rod 7 can be greatly suppressed.
In addition, as described above, the sound insulating device 30 is mounted over the entire length of the drill rod 7 so that the two bellows 32 and 34 cover only the portion of the drill rod 7. The operability of is not reduced. Moreover, since these two bellows 32 and 34 expand and contract in the longitudinal direction, the replacement work of the drill rod 7 is easy.

  Further, according to the sound insulating device 30, the drill rod 7 is covered by the double bellows structure having the air layer D2 between the two bellows 32 and 34 (see “double bellows” in FIG. 3). ) For example, as compared with the configuration in which the hole rod 7 is covered with a single bellows (see “single bellows single” in the same figure), noise is hardly transmitted even in comparison with a double bellows structure. Therefore, noise can be effectively reduced.

  In particular, in this sound insulating device 30, the thickness of the air layer D2 between the two bellows 32, 34 in the radial direction is reduced so that the reflected waves of noise interfere with each other and cancel each other. Since it is set according to the frequency band, the reflected waves of the noise interfere between the two bellows 32 and 34 and cancel each other, so that the noise of the target frequency can be effectively shielded.

  That is, as can be seen with reference to FIG. 3, both the bellows single and bellows double in the high frequency band (distant from the drill rod 7 at a position 64 m away) compared to the case without the sound insulation device (standard). From 3500 Hz onwards, it can be seen that the noise is reduced by distance attenuation. However, it can be seen that when the double structure is adopted for the bellows, the noise is reduced even in the 1500 Hz to 3000 Hz band as compared with the comparative example of the single bellows. In addition, about the noise which leaks from the opening part (lower fixed ring 38) of the sound insulation apparatus 30 close | similar to the ground (GL), a noise cannot reach | attain far away by the resistance by the ground GL. In addition, if this opening is directed to the cabin 5 side, it is effective for the visibility of the operator and for preventing the noise from reaching far away.

  Thus, according to this sound insulation device 30, the double bellows 32 and 34 are provided, and the two bellows 32 and 34 drill holes so as to cover only the portion of the drill rod 7 of the drilling device 3. Since the rod 7 is mounted over the entire length, the operability of the drilling device 3 can be maintained. Since the two bellows 32 and 34 are covered with a double bellows having an air layer D2 spaced apart by a predetermined distance, as shown in FIG. (Refer to “Standard” in the figure) In contrast, the A characteristic was 77.6 dB (A), whereas in the present invention in which the air layer D2 was provided between the bellows 32 and 34, 67.5 dB (A). (See “double bellows” in the figure).

The sound insulation device for a drilling machine according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, although the crawler drill has been described as an example of the drilling machine in the above embodiment, the present invention is not limited to this, and the present invention is applicable to various drilling machines as long as the drilling machine includes the drilling device. Needless to say, the sound insulation device of the drilling machine according to the above can be applied.

Further, for example, in the above embodiment, the radial thickness of the air layer D2 between the two bellows 32, 34 is reduced so that the reflected waves of noise interfere between the two bellows 32, 34 and cancel each other. Although it was explained with an example set according to the frequency band of the desired noise, not limited to this, a double bellows structure in which an air layer is provided between two bellows while maintaining the operability of the drilling machine Moreover, the noise from the part of the drilling rod of the drilling device can be reduced.
However, for example, in order to more effectively suppress a low frequency that reaches far away, the radial thickness of the air layer D2 is the noise between the two bellows 32 and 34 as in the above embodiment. It is preferable to set according to the frequency band of the noise to be reduced so that the reflected waves of each other interfere and cancel each other.

1 Crawler drill (drilling machine)
DESCRIPTION OF SYMBOLS 2 Main-body part 3 Drilling device 4 Engine room 5 Cabin 6 Traveling device 7 Drilling rod 8 Drifter 9 Feeding drive device 10 Guide shell 20 Slide cylinder 21 Hood mechanism 22 Centralizer 23 Hood pad 25 Boom 26, 27 Lift cylinder 30 Sound insulation device 32 1st bellows 34 2nd bellows 36 Upper fixed ring 38 Lower fixed ring

Claims (2)

  A sound insulation device for use in a drilling machine having a drilling device, comprising a double bellows covering the drill rod of the drilling device over its entire length, the double bellows being the drill rod A sound insulation device for a drilling machine, wherein the sound insulation device is stretched along a longitudinal direction of the drilling machine and spaced apart in a radial direction so as to have an air layer therebetween.   The thickness in the radial direction of the air layer between the two bellows is set according to the frequency band of the noise to be reduced so that the reflected waves of noise interfere and cancel each other between the two bellows. The sound insulation device for a drilling machine according to claim 1.

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