JP3006506U - Engine intake silencer - Google Patents

Abstract

(57) [Abstract] [Purpose] A gas turbine is the prime mover used in a package-type small portable generator, and a splitter-type intake silencer for damping intake noise. The sound absorbing silencer that has a structure that includes, and can maintain the sound absorbing performance as a splitter type without increasing the ventilation resistance. [Structure] In a flat duct, both sides of the horizontally long inlet are gradually reduced to a trapezoidal shape, and a sound absorbing wall of constant thickness is joined to the inner peripheral wall of which the outlet at the end is about the same size as the engine-side inlet area. A plurality of vertical partitions that divide the inside and outside of the sound absorbing wall at equal radial intervals when viewed from the outlet side shall be formed by forming a U-shaped cross section with a thin plate of hard resin, and the U-shaped opening is the outlet. Toward the side, three narrow frame plates extending in the direction perpendicular to the duct axis are fixedly integrated at equal intervals at the upper and lower sides of the duct axis to form a pillar for pressing and holding the surrounding sound absorbing wall through the frame plates. At the same time, it is configured to reflect and shield the U-shaped portion of the noise generated when it goes back into the intake air flow.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an intake silencer for attenuating a noise that flows backward from an engine intake port to an intake air flow, and more particularly, to an intake silencer for an engine for small devices mainly for packages.

[0002]

[Prior art]

 Conventionally, as an example of small equipment, there is a demand for a soundproof package type portable generator. Among them, the one using a gas turbine as an engine has a larger power generation output than a reciprocating engine, and therefore, it is small at the same power generation output.・ In addition to being lightweight, it has many excellent aspects such as the ability to use a wide variety of fuels, but on the other hand, there was the problem of large intake noise. However, recently, as shown in Fig. 6 as a noise attenuating means, by adopting a modified splitter type intake silencer that uses a sound absorbing material with excellent sound absorbing characteristics, it is possible to reduce the noise to the same level as the reciprocating engine, and the effect. Was recognized.

[0003]

[Problems to be solved by the device]

 The inside of the air intake duct has a splitter shape, and the sound absorbing wall with a certain thickness that is joined to the inner wall periphery and the sound absorbing partition wall with a certain thickness that divides the interior into equal vertical intervals are made by compressing the lock fiber or glass fiber to a certain thickness. A porous sound absorbing wall is formed by covering the same material with a cloth and molding it to the required size. In the arrangement inside the duct, the contact parts were adhered with an adhesive to make good use of the sound absorbing surface widely, but when the engine is a gas turbine, the intake air velocity is high at high speed and the rigidity is insufficient. Since the weak point that the sound absorbing wall is deformed or peeled off the adhesive over a long period of time was found, the sound absorbing performance was improved although the durability was improved as a result of reinforcement such as protection by covering it with a hard porous plate etc. In addition to this, there was the problem that the cost increased due to the increase in parts and processing man-hours.

[0004]

[Means for Solving the Problems] As a solution to the problem, the present invention replaces a plurality of vertical sound absorbing partition walls, which had been a weak point against a high-speed air flow in a splitter-type intake silencer, with a hard material thin plate in a transverse shape. Is U-shaped, and its parallel inner surface width and both outer surface widths are formed to correspond to the partition walls, and the U-shaped opening is directed to the outlet side to form a pillar for the upper and lower sound absorbing walls via a narrow frame plate. With this, in addition to reinforcement, by reflecting the energy of the sound coming out of the intake flow in the U-shape and also serving as a sound-insulating wall that does not let sound waves escape to the outside, depending on the U-shaped partition division arrangement, The effect is not inferior to that of the sound absorbing partition.

[0005]

【Example】

Hereinafter, a detailed description will be given based on an embodiment of the present invention with reference to the drawings. FIG. 1 is a schematic layout diagram of a package type gas turbine generator. The panel filter 12 incorporated in the flat duct 11 cleans dust-containing air that enters from the opening of the package 1 as indicated by the arrow and is sucked into the gas turbine 2. The combustion gas from the gas turbine 2 passes through the muffler 4 and is discharged to the outside through the opening on the side opposite to the inlet of the package 1 as indicated by the arrow. A flat fuel tank 5 is hung on the ceiling of the package 1. The generator 3, which is directly connected to the gas turbine 2, is characterized by having a large power generation output as a small size together with the prime mover due to being driven by high speed rotation. By using the gas turbine 2 as the power source, there is an advantage as the Package 1 type generator 3, but on the other hand, the noise that goes back into the intake air flow is large, so the flat type was adopted as a noise attenuation measure. A modified splitter intake air silencer 10 having a duct 11 as a base body. The suction side of the flat duct 11 expands horizontally to form a holding portion 13 for the panel filter 12 in the upper part of the front surface due to the positional relationship with other parts of the package 1, and the portions on both sides of the horizontal direction are reduced to a trapezoidal shape. Then, the outlet 14 at the end is shaped to be covered with the intake port on the engine side, thereby effectively expanding the filtration area of the filter 12 at the intake intake port and relaxing the ventilation resistance. FIG. 2 is a half sectional view of a modified splitter type intake silencer 10 according to the present invention. The intake silencer 10 provided adjacent to the filter 12 along the suction direction extends up to the middle of the duct 11, and has sound absorbing walls 15 of constant thickness on both sides of the inner circumference and the same sound absorbing wall 16 on the upper and lower surfaces. Each of the two partition walls 17 and 18 which are affixed to each other and which are vertically divided into equal radial intervals when viewed from the outlet 14 side are two partition walls 17 'and 18' of the conventional type 10 'shown in FIG. In the same arrangement, thin resin thin plates are molded in a U shape, and the narrow frame plates 19, 20, 21 are fixed to the upper and lower parts with their openings facing the exit side and are connected at right angles to the axial direction. In addition to pressing the upper and lower sound absorbing walls 16 to form pillars through each of the above two, each end of each of the frame plates 19, 20, and 21 is extended to both sound absorbing walls 15, and is slightly opposed to the upper and lower sides along the inner wall. Bend the length and press and hold the end as shown in Fig. It has also become holding the position 17,18. Further, to prevent the movement in the axial direction, as shown in the enlarged view of FIG. 4, there are five claw pieces provided on the frame plate 19 to the L-shaped reinforcing frame 22 fixed to the inner periphery of the rear portion of the filter holding portion 13 of the duct 11. 19 ₋₁ is hooked, and the rear part of the case of the filter 12 restrains its forward movement. With this structure, even if the intake air flow is fast, the ends of the partition walls 17 and 18 that face the air flow are U-shaped, so that the ventilation resistance is alleviated and the inside of the U-shaped structure becomes a pillar that doubles as a sound insulation wall. It is a thing. The area of the intake silencer 10 is set to the middle of the duct 11 so that the total area of the end openings between the partition walls 17 and 18 does not become smaller than the area of the intake port on the engine side, and the ventilation resistance in this part is reduced. It avoids the increase of. FIG. 5 shows another embodiment according to the present invention, which is different from the above-mentioned embodiment in that the number of the partition walls 17 and 18 is changed to two, and the length of the partition wall 23 is shortened by about 1/2. 24, two in total and 251 in total, five in total, are alternately arranged in two rows in the horizontal direction as shown, and other than that are the same as in FIG. 2 of the above-mentioned embodiment. According to this arrangement, the ventilation resistance is almost the same as that of the four partition walls of the above-described embodiment, and the five partition walls serve as sound insulation walls, so that the effect as the intake silencer is improved.

[0006]

[Effect of device]

 (1) In the modified splitter type intake silencer, if the prime mover of the packaged generator is a gas turbine, the conventional sound absorbing bulkhead has a sound absorbing effect, but lacks rigidity and lacks durability against high-speed flow. In order to supplement the sound absorption partition wall, instead of a conventional sound absorption partition wall, a hard resin thin plate is formed into a U-shaped partition wall, and the opening of the partition wall is used as a reinforcement strut, so that the sound emitted against the intake air flow By also functioning as a sound insulation wall that reflects energy within the U-shape, it is possible to obtain an intake silencer that has a sound absorption effect that is not inferior to the conventional type and is durable. (2) As shown in Fig. 7, the sound absorption performance of the modified reciprocating engine is similar to that of the reciprocating engine of the portable generators manufactured by other companies. It can be seen that the gas turbine noise attenuation effect by the intake silencer is remarkable. Although the above is described based on the embodiment according to the present invention, it is needless to say that the present invention is not limited to this and various changes and modifications can be made according to the idea of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic interior perspective view of a packaged gas turbine generator to which the present invention is applied.

FIG. 2 is a half sectional view of an intake silencer according to the present invention.

3 is a cross-sectional view taken along the line AA in FIG.

4 is an enlarged view of part B in FIG.

FIG. 5 is a sectional view of an intake silencer according to another embodiment of the present invention.

FIG. 6 is a half sectional view of a conventional intake silencer.

FIG. 7 is a noise comparison diagram of a portable generator with other manufacturers.

[Explanation of symbols]

1 Package 2 Gas Turbine 3 Generator 4 Muffler 5 Fuel Tank 10 Intake Silencer 11 Duct 12 Panel Filter 15 Sound Absorption Wall 16 Sound Absorption Wall 17 Partition Wall 18 Partition Wall 19 Frame Board 19 _-1 Claw Piece 22 Reinforcement Frame 23 Partition Wall 24 Partition Wall 25 Partition Wall

Claims (1)

[Scope of utility model registration request] 1. A flat-shaped duct for holding a panel filter having a rectangular air inlet in a horizontally long horizontal shape with a filtering surface being vertical, the longitudinal sides after the filter are trapezoidal, and the outlet is approximately the same as the engine inlet area. The sound absorbing wall having a constant thickness is joined to the inner peripheral wall that is gradually reduced until it becomes, and a plurality of vertical constant thickness sound absorbing partition walls that divide the inside into radial equal intervals when viewed from the outlet side are arranged. In the modified splitter type intake silencer, instead of a plurality of sound absorbing partition walls, a hard material thin plate is molded so that the transverse shape is U-shaped and the parallel inner surface width and outer surface width are equivalent to the partition walls, and the U-shaped opening is formed. An intake silencer for an engine, which has a pillar-shaped partition wall facing the outlet side.