JPH079362A - Silencer for air nailing machine - Google Patents

Abstract

PURPOSE:To provide a silencer for an air nailing machine which can attenuate noise produced when compressed air is released outside, can prevent a noise suppressing effect from being degraded, and the operation of the nailing machine from being defective at low temperature, and also can be small in size and simple in structure. CONSTITUTION:A first cratering 1 and a second cratering 2 are combined with each other by a first communicating groove 4, the second cratering 2 and a third cratering 3 are combined with each other by a second communicating groove 5, and a cover having a structure where a third communicating groove is combined with the third cratering 3, is closely attached to the outer wall surface of a main body provided with an exhaust port so as to be fixed, so that the first cratering 1 is combined with the exhaust port, and concurrently the second cratering 2 and the third cratering 3 are formed into a first expansion chamber and a second expansion chamber respectively. And concurrently, the first cratering 1 and the first expansion chamber 2 are combined with each other by the first communicating groove 4, the first expansion chamber 2 and the second expansion chamber 3 are combined with each other by the second communicating groove 5, and the second expansion chamber 3 is communicated with atmosphere through a tail pipe forming a third communicating groove 6, so that an exhaust passage having the characteristics of an expansion type noise suppressor is thereby formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silencer for an air nailer that reduces noise of the air nailer.

[0002]

2. Description of the Related Art Noise generated during nailing work by an air nailing machine is divided into a hammering sound of nailing and an exhaust sound of exhausting used compressed air, but the exhaust noise occupies a large proportion. The exhaust noise is caused by the pressure wave when the compressed air is released to the atmosphere and the turbulent flow caused by the compressed air exhaust, and is 2.0 to 6.3 kHz.
The frequency component of has a large level. In the conventional air nailing machine, in order to suppress the flow velocity of the air in order to reduce the exhaust noise, as shown in Japanese Utility Model Publication Nos. 58-8457 and 61-42788, the exhaust passage is porous. A porous material such as polyethylene is inserted. When the porous material is inserted into the exhaust passage, many small holes are formed in the exhaust passage. Therefore, adiabatic expansion of the compressed air causes moisture to freeze in the small holes at low temperature, and the exhaust passage is blocked by a nailing machine. There was a drawback that the noise reduction effect was reduced at the same time that the malfunction occurred. In addition, dust is likely to be clogged in the porous material, which deteriorates rapidly due to aging and requires labor for replacement work. In addition, in terms of manufacturing, the structure for obtaining the sound deadening effect is complicated, resulting in an increase in production cost.

[0003]

Problems to be Solved by the Invention JP-A-55-2899
In the official gazette, a muffler that does not use a porous material is shown, but since the air flow is discharged through the small holes, the problem of freezing of the small holes and clogging cannot be completely solved. Since the chambers are connected to each other via the recesses in the wall, there is a problem that the axial dimension of the nail driver increases. An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to provide a muffler for an air nailing machine having a small size and a simple structure that reduces exhaust noise.

[0004]

The object of the present invention is to provide a silencer in a cylinder having at least one exhaust passage consisting of a plurality of expansion chambers and one or more elongated connecting grooves connecting the expansion chambers in series. It is solved by providing it between an exhaust valve for exhausting used air and an exhaust port.

[0005]

The exhaust having the characteristics of an expansion silencer is provided by providing the silencer for an air nailer constructed as described above between the exhaust valve for exhausting the used air in the cylinder and the exhaust port. A passage is formed. The noise generated at the moment when the compressed air is released to atmospheric pressure enters the expansion chamber and is reflected by the expansion chamber.
Interference and attenuation. In addition, the attenuation amount is further increased by providing the elongated communication groove. At low temperatures, no icing occurs because no porous material is used inside the silencer. In terms of structure, each expansion chamber is connected by a long and narrow communication groove, so there is a large degree of freedom in arranging the expansion chambers, and the size of the nailing machine in the axial direction can be kept small even if a silencer is attached, and noise is reduced. Since the structure and installation of the container are simple, it is possible to keep the increase in production cost low.

[0006]

1 is a perspective view of a muffler member 12 constituting a muffler for a pneumatic nailing machine showing an embodiment of the present invention, and FIG.
Is an enlarged perspective view of a cross section of the silencer member 12,
FIG. 3 is an external view when the silencer member 12 is attached to the nail driver. FIG. 4 is an external view of the nailing machine main body. The silencer member 12 formed of a material having elasticity such as urethane rubber is
Five recesses 1 to 3 and four communication grooves 4 and 5 for connecting the recesses 1 to 3 are provided, and two similar exhaust passages are provided. The first dent 1 and the second dent 2 are connected by a first communication groove 4, and the second dent 2 and the third dent 3 are connected by a second communication groove 5. A third communication groove 6 is connected to the third recess 3. As shown in FIG. 2, a slight dent 13 is provided at the center of the mounting surface of the silencer member 12 with the nailer body 8. Therefore, as shown in FIG. 3, when the muffler member 12 is attached to the outer wall surface of the main body provided with the exhaust port 7 with a screw, the end portion of the dent 13 can be spread and closely fixed. By mounting on the nailer body 8, the first recess 1 is connected to the exhaust port 7, and the recesses 2 and 3 and the communication grooves 4 and 5 are formed as an expansion chamber and a connecting pipe, respectively. The communication groove 6 is formed as a tail pipe. As a result, an exhaust passage having the characteristics of the expansion silencer is formed.

Here, the number of exhaust passages formed of the plurality of dents 1 to 3 and the communication grooves 4 and 5 for connecting the plurality of dents 1 to 3 in series may be set to an arbitrary number.
Is generally provided at the center of the housing end piece 10, so if a plurality of exhaust passages are provided and distributed to the left and right with respect to the dent 1 that is connected to the exhaust port 7, the limited silencer volume can be effectively utilized. You can For example, in the muffler member 12 shown in FIG. 1, two exhaust passages each including the dents 2 and 3 and the communication grooves 4 and 5 are provided, and the exhaust passage 7 is divided into left and right parts with respect to the first dent 1 that is connected to the exhaust port 7. Are arranged. The noise generated when the compressed air is released to the atmospheric pressure, after entering the first dent 1 from the exhaust port 7,
It is divided into two by the first communication groove 4 and enters the second recess 2 respectively. Here, the noise is reflected, interfered and attenuated.
After that, it passes through the second communication groove 5, enters the third recess 3, is reflected and interferes, is further attenuated, and is released from the third communication groove 6 to the outside. Exhaust air is also released to the outside air through the exhaust passage in the same manner, but in order to suppress the generation of fluid noise when compressed air flows out, it is effective to have a shape without an acute angle portion in the exhaust passage. Target. For example, dents 1-3
The corners of the connecting portions of the communication grooves 4 to 6 may be rounded. In addition, if the dents 1 to 3 are arranged so that the exhaust passage is not linear, the flow velocity is reduced when the exhaust air passes through the expansion chamber and the connecting pipe, and it is possible to suppress the generation of fluid noise. Further, the cross-sectional areas of the first dent 1 and the second dent 2, the second dent 2 and the third dent 3, and the communication grooves 4 to 6 that connect the third dent and the outside air are in consideration of the exhaust air amount of the nailing machine. Just decide.

5 and 6 show another embodiment of the present invention.
In FIG. 5, a plurality of expansion chambers 2 and 3 and one or more elongated communication grooves 5 that connect the expansion chambers 2 and 3 in series are provided in the housing end piece 10 of the air nailer main body 8 and the lid 11 is provided as described above. The exhaust passage having the characteristics of the expansion type silencer is formed by closely attaching to the housing end piece 10. FIG. 6 shows a silencer member 1 having a plurality of expansion chambers 2 and 3 and a plurality of elongated communication grooves 5 that connect the expansion chambers 2 and 3 in series.
2 is built in the nail driver main body 8 and the silencer member 12 is closely attached to the inside of the housing end piece 10 to form an exhaust passage having the characteristics of an expansion silencer.

[0009]

According to the present invention, in addition to the noise reduction effect of the sound waves in the expansion chamber due to the noise generated when the compressed air in the pneumatic nailing machine is released to the outside air, the slender communication groove is used. It is possible to obtain a further noise reduction effect. Further, since no porous material or small holes are used in the interior, freezing of water at low temperature, deterioration of sound deadening function, and malfunction of nailing machine do not occur.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a silencer member for a pneumatic nailer of the present invention.

FIG. 2 is an enlarged perspective view of a cross section of FIG.

FIG. 3 is an external view when the silencer member of FIG. 1 is attached to a nailing machine.

FIG. 4 is an external view of a nailing machine main body to which the silencer member of the present invention is attached.

FIG. 5 is an external view showing another embodiment of the silencer member of the present invention.

FIG. 6 is an external view showing another embodiment of the muffler member of the present invention.

[Explanation of symbols]

1-3, 13 are dents, 4-6 are communication grooves, 7 is an exhaust port,
8 is a nailing machine main body, 9 is a mounting screw hole, 10 is a housing end piece, 11 is a lid, and 12 is a silencer member.

Claims (4)

[Claims] 1. In an air nailer for driving a piston by compressed air to drive a nail, a plurality of expansion chambers are provided between an exhaust valve and an exhaust port for exhausting used air in a cylinder, and a plurality of these expansion chambers. A silencer for an air nailer, which has one or more elongated communication grooves connecting chambers in series. 2. The pneumatic nailing machine according to claim 1, wherein the plurality of expansion chambers and the communication groove are formed by mounting a cover having a dent on the outer wall of the main body of the pneumatic nailing machine. Silencer. 3. The silencer for an air nailing machine according to claim 1, further comprising a plurality of exhaust passages having the plurality of expansion chambers and one or more elongated communication grooves connecting the expansion chambers in series. . 4. The cover having the dent is formed of an elastic material such as urethane rubber, and the center of the mounting surface with the nailer is slightly indented so that the cover is adhered to the nailer main body. The silencer for an air nailer according to claim 2, wherein the silencer is increased.