JP5909112B2 - Silencer for turbocharger - Google Patents

Description

  The present invention relates to a silencer for a supercharger applied to, for example, a large diesel engine for marine use or power generation.

  2. Description of the Related Art Conventionally, a supercharger that compresses combustion air of an internal combustion engine and forcibly sends high-density air into a combustion chamber is known. For example, it is widely used in large diesel engines for ships and power generation. In such a turbocharger, a compressor for compressing combustion air and a turbocharger turbine serving as a drive source for the compressor are coaxial, housed in a housing, and rotate integrally. Note that the turbocharger turbine is driven by the energy held by the exhaust gas of the internal combustion engine.

In such a supercharger, a silencer for a supercharger as disclosed in, for example, Patent Document 1 below is used in order to mute noise generated from intake air. This silencer for a supercharger employs a configuration in which a plurality of two-folded and bent (similar Z-shaped) sound absorbing splitters are combined as a silencer element (sound absorber) to maintain the sound deadening performance and reduce the low pressure loss.
In addition, other turbocharger silencers include a silencer element in which a curved sound absorbing splitter is combined in place of the substantially Z shape.

Japanese Patent Laid-Open No. 11-200969

The conventional turbocharger silencer described above has a problem in that the shape and structure of the silencer element are complicated, so that it takes time to process and assemble the silencer element, and the manufacturing cost of the element increases.
Although it may be possible to reduce the cost by making the shape of the silencer element a simple cylinder, a problem has been pointed out that the silencer performance is somewhat inferior due to the length restriction.

From such a background, it has been desired to develop a silencer for a supercharger that can secure a desired sound absorption performance and can be easily manufactured and is inexpensive.
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a silencer for a supercharger that can secure a sound absorbing performance and can reduce a manufacturing cost.

In order to solve the above problems, the present invention employs the following means.
A silencer for a supercharger according to the present invention is a silencer for a supercharger that is attached to an upstream side of an inlet portion of an intake air introduction path for introducing intake air to be compressed by a compressor portion and absorbs intake noise. An intake air inlet opening formed on the outer peripheral surface of the substantially cylindrical casing, and the intake air introduced from the intake air inlet opening is turned by approximately 90 degrees and guided to the intake air introduction path An air flow path, an intake air outlet opening formed on one end face side of the casing, a sound absorption cylinder attached to the intake air inlet opening and having a curved flow path that is a cylinder and whose cross-sectional area does not change; and the sound absorption And a support plate that includes an air flow hole substantially concentric with the cylinder and that fixes and supports the sound absorbing cylinder inserted at a predetermined position of the intake air inlet opening.

According to such a turbocharger silencer, since the sound absorbing cylinder attached to the intake air inlet opening has a curved shape without changing the cross-sectional area, the sound absorbing cylinder changes the cross-sectional area. The flow path is curved without any problems. Therefore, by increasing the length while maintaining the flow path cross-sectional area of the sound absorbing cylinder, it is possible to maintain the flow rate of the intake air and improve the noise reduction performance.

In the above invention, it is preferable that the sound absorbing material is attached by being inserted into a space formed between the sound absorbing cylinders installed adjacent to each other, and thereby, from the intake air flowing through the space The generated noise is also absorbed by the sound absorbing material provided so as to fill the space, and the noise reduction performance is improved.
In this case, for example, a plate material provided with a large number of small holes in portions other than the air circulation holes, such as punching metal, functions as a stopper for the sound absorbing material to be inserted and reflects noise. Can be suppressed.

  According to the above-described silencer for a supercharger of the present invention, it is possible to ensure good sound absorption performance, reduce manufacturing costs, and improve maintainability.

It is a longitudinal cross-sectional view (AA sectional drawing of FIG. 4) which shows one Embodiment of the silencer for superchargers which concerns on this invention. It is a principal part cross section (BB sectional drawing of FIG. 1) which shows the example of arrangement | positioning which used the columnar sound-absorbing material in addition to the sound-absorbing cylinder which twisted and curved the cylinder. It is a figure which shows the structural example of the silencer for superchargers which concerns on this invention, and is a front view which shows an internal cross section about one part. It is sectional drawing which shows the internal structure outline | summary of FIG. It is an external appearance perspective view which shows the structural example of the sound-absorbing material applied to this invention. It is a longitudinal section showing an example of 1 composition of an exhaust turbine supercharger provided with a silencer for superchargers concerning the present invention.

Hereinafter, a silencer for a supercharger according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6.
FIG. 6 is a longitudinal sectional view showing a configuration example of an exhaust turbine supercharger equipped with a silencer for a supercharger according to the present invention. The silencer for a supercharger according to the present invention is such an exhaust turbine supercharger. It can be applied to the machine 10.
The illustrated exhaust turbine supercharger 10 is mounted on, for example, a marine diesel engine (such as a low-speed two-cycle diesel engine) (not illustrated) and communicates with the inside of a cylinder liner (not illustrated) that constitutes the marine diesel engine. (Not shown) is a device for supplying compressed air.

  As shown in FIG. 6, in the exhaust turbine supercharger 10, a gas inlet casing 11, a gas outlet casing 12, a bearing base 13, and an air guide casing 14 on the compressor side are integrally fastened by bolts (not shown). It is comprised by. The rotor shaft 15 is rotatably supported in the bearing base 13 by a thrust bearing 16 and radial bearings 17 and 18, and a turbine 19 constituting a turbine portion is solidified at one end, and a compressor portion is provided at the other end. The compressor impeller (impeller) 20 which comprises is consolidated.

The turbine 19 on one end side has a large number of blades 19a on the outer periphery. The blade 19 a is disposed between an exhaust gas introduction path 22 provided in the gas inlet casing 11 and an exhaust gas discharge path 23 provided in the gas outlet casing 12.
On the other hand, the compressor impeller 20 on the other end side has a large number of blades 20a on the outer peripheral portion. The blade 20 a is disposed behind an intake air introduction path 24 provided in the air guide casing 14. The intake air introduction path 24 is connected to the spiral chamber 25 via the compressor impeller 20, and the spiral chamber 25 is connected to the combustion chamber of the engine via an intake air introduction path (not shown).

  The exhaust turbine supercharger 10 described above includes a supercharger silencer 30 upstream of the intake air introduction path 24. The turbocharger silencer 30 is a device that is installed upstream (upstream) of the intake air compressed by the compressor section into the intake air introduction path 24, that is, upstream of the inlet section of the intake air introduction path 24. There is a filter function that rectifies the air flow by allowing the intake air to pass therethrough, and a silencing function that absorbs noise generated from the intake air.

As shown in FIGS. 1 to 6, the turbocharger silencer 30 of the present embodiment includes an intake air inlet opening 32 formed on the outer peripheral surface of a substantially cylindrical casing 31, and the intake air inlet opening. The intake air flow path 33 that guides the intake air introduced from 32 to the intake air introduction path 24 by changing its direction by approximately 90 degrees, the intake air outlet opening 34 formed on one end face side of the casing 31, and the intake air A sound-absorbing tube 40 that is twisted and curved by a cylinder attached to the inlet opening 32 and a columnar sound-absorbing material 60 that is attached by being inserted into a space formed between the adjacent sound-absorbing tubes 40. And a support plate 50 that includes an air circulation hole 51 that is substantially concentric with the sound absorbing cylinder 40 and that fixes and supports the sound absorbing cylinder 40 inserted at a predetermined position of the intake air inlet opening 32.
The above-described sound absorbing cylinder 40 is attached to the intake air inlet opening 32 by being inserted from the casing outer peripheral side, for example.

  A filter 35 and an expanded metal 36 are provided on the outer peripheral side of the intake air inlet opening 32 in order from the outside in order to prevent foreign substances from entering with the intake air. In this case, the expanded metal 36 becomes a member that holds the shape of the filter 35 and is detachably attached to an appropriate position of the casing 31.

  The support plate 50 in this embodiment includes an outer support plate 52 and an inner support plate 53 so as to support the vicinity of both ends of the sound absorption cylinder 40 that functions as a silencer element (sound absorber). You may make it support both ends and a center part. The outer support plate 52 and the inner support plate 53 are provided with a large number of air flow holes 51 for inserting and supporting the sound absorbing cylinders 40 so as to coincide with each other in the radial direction.

The casing 31 is formed by opposingly arranging two disks 31a and 31b and connecting them by a plurality of outer columnar members 31c and an inner support plate 53, but this connection structure is particularly limited. It will never be done.
The outer columnar members 31c are members that connect the vicinity of the outer peripheral ends of the disks 31a and 31b to each other, and are arranged at substantially equal pitches in the circumferential direction. In this case, welding or bolting can be employed for the connection between the columnar member 31c and the disks 31a and 31b. In the casing 31 of the present embodiment, the disk 31a side serving as a front panel has a welding structure, and the disk 31b side serving as a rear panel has a bolting structure.

The outer support plate 52 of the support plate 50 is divided into a plurality of circumferential directions according to the arrangement of the columnar members 31c. The outer support plate 52 can be attached to and detached from the columnar member 31c from the outside, for example, by bolting or the like.
On the other hand, the inner support plate 53 of the support plate 50 is a member that connects the vicinity of the middle in the circumferential direction of the disks 31a and 31b. The inner support plate 53 is a member formed in, for example, a cylindrical shape and formed with air circulation holes 51 similar to the outer support plate 52, and is fixed to the disks 31a and 31b by bolting or the like.

The intake air flow path 33 is a space that guides the intake air introduced from the intake air inlet opening 32 to the intake air introduction path 24 by changing its direction by approximately 90 degrees. That is, the intake air flow path 33 changes the direction of the intake air flowing from the intake air inlet opening 32 and passing through the sound absorbing cylinder 40 by approximately 90 degrees in the space on the inner peripheral side of the inner support plate 53. By doing so, it leads to the intake air outlet opening 34.
The intake air outlet opening 34 is formed on one end surface side of the casing 31 and is connected to the intake air introduction path 24, and serves as an outlet for supplying intake air to the compressor unit.

The sound absorbing cylinder 40 is a cylindrical member having a cross-sectional structure of at least three layers, for example. That is, the sound absorbing cylinder 40 is formed of, for example, expanded metal in a cylindrical shape that serves as a reinforcing member (base material), and the outer periphery of the cylinder is covered with a sound absorbing material such as glass cloth. A three-layer structure covered with a peripheral material such as a foil.
The sound absorbing cylinder 40 is attached by being inserted in the radial direction from the outer peripheral side of the intake air inlet opening 32 with the filter 35, the expanded metal 36 and the outer support plate 52 removed. In such a detachable state of the sound absorbing cylinder 40, a large number of air circulation holes 51 are open.

  In the configuration example shown in FIG. 2, seven sound absorbing cylinders 40 are arranged in a zigzag pattern in the width direction with respect to the area of one outer support plate 52, but the sound absorbing cylinders 40 in one area are arranged. The arrangement, number, etc. are not particularly limited. Further, at both end portions of one row, for example, a halved sound absorbing cylinder 40 'is used to adjust the dimension in the row direction.

  Now, the sound absorbing cylinder 40 of this embodiment has a cylindrical shape in which a cylinder is twisted and curved. That is, the axis of the sound absorbing cylinder 40 of this embodiment is a curved line. For this reason, the sound absorbing cylinder 40 includes a long flow path that is curved without changing its cross-sectional area, as compared with a linear sound absorbing cylinder. Note that both ends of the sound absorbing cylinder 40 are supported by the outer support plate 52 and the inner support plate 53.

Specifically, in order to increase the length of the sound absorption channel, it is conceivable to arrange a cylindrical sound absorption cylinder on the rotating hyperboloid. However, in the case of a rotating hyperboloid, the constriction occurs in the center portion, so that the casing 31 in which the sound absorbing cylinder is installed becomes large as it is, and as a result, the entire apparatus becomes large.
Therefore, the sound absorbing cylinder 40 of the present embodiment forms a long intake air flow path that is curved without changing the cross-sectional area by twisting and arranging the cylindrical sound absorbing cylinder. Thus, the noise reduction performance can be improved by maintaining the flow rate. In addition, since it is possible to eliminate a constricted portion such as a rotating hyperboloid, it is possible to prevent an increase in the size of the silencer 30 for the supercharger.

Incidentally, in order to obtain the above-described sound absorbing cylinder 40 by twisting and bending a cylinder, it has been disclosed in, for example, Japanese Patent Application Laid-Open Nos. 7-51752, 58-68430, and 2010-188406. Adopt technology. That is, the sound absorbing cylinder 40 is manufactured by, for example, forming a cylinder with an expanded metal of a reinforcing member (base material), twisting the cylinder by applying the above-described technique, and bending the outer periphery thereof. What is necessary is just to cover with a sound-absorbing material.
The large number of sound absorbing cylinders 40 manufactured in this way can be prevented from increasing in size by having both ends arranged in substantially the same manner as the rotating hyperbola, so that there is no constriction at the center.

In this embodiment, since the cylindrical sound absorbing cylinders 40 are arranged in a staggered manner, a space portion is formed between the outer peripheral surfaces of the adjacent sound absorbing cylinders 40. A sound absorbing material 60 is inserted and installed. For example, as shown in FIG. 5, the sound absorbing material 60 is formed by forming a sound absorbing material made of glass cloth or the like into a solid substantially triangular prism shape, and the outer periphery is covered with an outer peripheral material such as an aluminum foil as necessary. May be.
Note that a plurality of types of sound absorbing materials 60 (four types of sound absorbing materials 60a to 60d in the configuration example of FIG. 2) are used depending on the shape of the space.

The above-described sound absorbing cylinder 40 is assembled by being inserted radially inward from the intake air inlet opening 32 toward the air circulation hole 51 of the inner support plate 53. As a result, the air circulation holes 51 of the inner support plate 53 support and position one end of the sound absorbing cylinder 40, so that all of the sound absorbing cylinders 40 can be easily inserted sequentially. Therefore, not only at the time of initial assembly, but also at the time of maintenance after being attached to the exhaust turbine supercharger 10, the sound absorbing cylinder 40 can be easily replaced with the filter 35, the expanded metal 36 and the outer support plate 52 removed. It becomes possible to do.

  That is, in the turbocharger silencer 30 of the present embodiment, the support plate 50 includes an outer support plate 52 and an inner support plate 53 that support the vicinity of both ends of the sound absorbing cylinder 40, and the outer support plate 52 is attached from the outside. Since the outer support plate 52 is removed, it is easy to insert or remove from the outer peripheral side of the casing 31 when the sound absorbing cylinder 40 is assembled or replaced. Can be implemented.

The sound absorbing material 60 is assembled by inserting it inward in the radial direction from the intake air inlet opening 32 , similarly to the sound absorbing cylinder 40. Since the sound absorbing material 60 can be changed in a relatively flexible shape, it can be easily attached so as to be pushed into the space, and the adhesion to the outer peripheral surface of the sound absorbing cylinder 40 is also good.
In this case, a support hole (not shown) may be provided in the inner support plate 53, and an end portion may be inserted into the support hole. As a result, the sound absorbing material 60 can be assembled with its end portions positioned easily. The outer support plate 52 may also be provided with support holes (not shown) to support both ends of the sound absorbing material 60.

  Alternatively, in the case of such a sound absorbing material 60, since the sound absorbing cylinder 40 side is supported by the outer support plate 52 and the inner support plate 53, the length is slightly shorter than the sound absorbing cylinder 40, and the outer peripheral surface of the adjacent sound absorbing cylinder 40. As long as it has a cross-sectional shape so as to be in contact with the space, it may be configured to be inserted so as to fill the space. In this case, the periphery of the sound absorbing material 60 is constrained in contact with the sound absorbing cylinder 40, and both end portions of the sound absorbing material 60 are in contact with the outer support plate 52 and the inner support plate 53 to be restrained from moving in the axial direction. .

As described above, the turbocharger silencer 30 of the present embodiment adopts a cylindrical shape twisted and bent as the sound absorption or the like 40, so that the flow of the long intake air curved without changing the cross-sectional area. As a result, a flow rate of intake air can be maintained and noise reduction performance can be improved. In addition, since the cylindrical sound absorbing cylinder 40 can be attached and detached by insertion from the outer peripheral side or the like, the assembling work and the replacement work of the sound absorbing cylinder 40 can be easily performed. Accordingly, the silencer 30 for the supercharger according to the present embodiment realizes reduction in manufacturing cost and improvement in maintenance due to improvement in workability as well as ensuring sound absorption performance.
And since the columnar sound-absorbing material 60 is inserted and attached to the space formed between the sound-absorbing tubes 40 installed adjacent to each other, the space portion generated when the cylindrical sound-absorbing tubes 60 are arranged side by side. The noise generated from the intake air flowing through it is also absorbed by the sound absorbing material 60 provided so as to fill the space, so that the noise reduction performance of the turbocharger silencer 30 as a whole is improved.

  By the way, in the silencer 30 for a supercharger mentioned above, many small holes were provided in the part other than the air circulation hole 51 in the support plate 50, that is, in the region of the support plate 50 where both end surfaces of the sound absorbing material 60 are located. It is desirable to use a plate material (for example, punching metal). Such a plate material such as punching metal functions as a stopper for the sound absorbing material 60 to be inserted and does not block the flow of the intake air passing through the sound absorbing material 60. For this reason, since the reflection of the noise in the turbocharger silencer 30 can be suppressed, the noise reduction performance of the entire turbocharger silencer 30 can be further improved.

As described above, according to the silencer 30 for the supercharger of the present embodiment described above, by adopting the sound absorbing cylinder 40 and additionally installing the sound absorbing material 60, it is possible to ensure good sound absorbing performance, reduce manufacturing costs, and maintainability. Can be improved.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary, it can change suitably.

DESCRIPTION OF SYMBOLS 10 Exhaust-turbine supercharger 19 Turbine 20 Compressor impeller 24 Intake air introduction path 30 Supercharger silencer 31 Casing 31a, 31b Disc 31c Outer columnar member 32 Intake air inlet opening 33 Intake air flow path 34 Intake air outlet opening Part 35 Filter 36 Expanded metal 40 Sound absorbing cylinder 50 Support plate 51 Air circulation hole 52 Outer support plate 53 Inner support plate 60 Sound absorbing material

Claims (2)

A silencer for a supercharger that is attached to the upstream side of an inlet portion of an intake air introduction path for introducing intake air to be compressed by a compressor portion and absorbs intake noise,
An intake air inlet opening formed on the outer peripheral surface of the substantially cylindrical casing;
An intake air flow path that guides the intake air introduced from the intake air inlet opening to the intake air introduction path by changing its direction by approximately 90 degrees;
An intake air outlet opening formed on one end surface side of the casing;
A sound-absorbing cylinder attached to the intake air inlet opening and having a curved channel whose cross-sectional area does not change ;
A support plate having an air flow hole substantially concentric with the sound absorbing cylinder, and fixedly supporting the sound absorbing cylinder inserted into a predetermined position of the intake air inlet opening;
A silencer for a supercharger characterized by comprising:   The silencer for a supercharger according to claim 1, wherein a sound absorbing material is attached by being inserted into a space formed between the sound absorbing cylinders installed adjacent to each other.

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