JP2012225221A - Muffler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a muffler having small ventilation resistance and a high muffling effect.SOLUTION: An inner cylinder portion 61 forms a part between a compressor wheel 51 and an engine 30, of an intake passage 11 in which intake air flows to the engine 30. An outer cylinder portion 62 is provided at the radial outside of the inner cylinder portion 61, and has a larger inner diameter than an outer diameter of the inner cylinder portion 61. A first annular portion 63 closes an annular opening between one end of the inner cylinder portion 61 and one end of the outer cylinder portion 62. A second annular portion 64 closes an annular opening between the other end of the inner cylinder portion 61 and the other end of the outer cylinder portion 62 to form a cylindrical space 67 between the inner cylinder portion 61, the outer cylinder portion 62 and the first annular portion 63. A communicating pipe 65 forms a communicating passage 650 for connecting the cylindrical space 67 with an opposite side of the engine 30 in a first virtual plane S1 of the intake passage 11.

Description

  The present invention relates to a muffler provided in an intake system of an internal combustion engine (hereinafter referred to as “engine”).

2. Description of the Related Art Conventionally, an engine equipped with a supercharger is known for the purpose of improving output, improving torque in a practical rotation range, or improving fuel efficiency. A silencer that suppresses noise caused by supercharging is provided between the supercharger and the engine.
In Patent Document 1, the silencer includes an inner wall formed from a porous material such as a metal net, an outer wall formed from a metal such as stainless steel, and a sound absorbing material such as a fiber built between the inner wall and the outer wall. It absorbs the pulsation generated by supercharging and suppresses the radiation sound to the outside.

JP 2005-514550 A

However, the presence of a large number of holes in the inner wall causes air flow resistance on the inner wall surface, thereby generating ventilation resistance. For this reason, the flow rate of intake air is reduced, and the supercharging effect is reduced. Further, when foreign matter such as oil or depot adheres to the hole in the inner wall, the air flow is inhibited and the silencing effect is reduced.
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a silencer that has a low ventilation resistance and a high silencing effect.

  According to the invention which concerns on Claim 1, a silencer suppresses the noise at the time of supercharging by the compressor wheel which supercharges the intake_air | air_intake to an engine. The silencer includes an inner cylinder part, an outer cylinder part, a first annular part, a second annular part, and a communication pipe. The inner cylinder part forms a part between the compressor wheel and the engine in the intake passage through which intake air to the engine flows. The outer cylinder part is provided on the outer diameter side of the inner cylinder part, and has an inner diameter larger than the outer diameter of the inner cylinder part. The first annular portion closes an annular opening between one end portion of the inner cylinder portion and one end portion of the outer cylinder portion. The second annular portion closes the annular opening between the other end portion of the inner cylinder portion and the other end portion of the outer cylinder portion, so that it is between the inner cylinder portion, the outer cylinder portion, and the first annular portion. A cylindrical space is formed. The communication pipe forms a communication path that connects the cylindrical space and the first virtual plane including the end face of the compressor wheel on the engine side in the intake path to the side opposite to the engine.

  In the present invention, due to the rotation of the compressor wheel, a negative pressure is generated on the opposite side of the engine from the first virtual plane including the end surface on the engine side of the compressor wheel in the intake passage. Thereby, the air in the cylindrical space is sucked into the intake passage via the communication passage. For this reason, the cylindrical space approaches a vacuum state by sucking out air, and the degree of vacuum increases. Therefore, it can suppress that the vibration of an inner cylinder part is transmitted to an outer cylinder part, and can suppress that the noise by the pulsation of the intake air supercharged by the compressor wheel is discharge | released outside. In addition, since there are no holes or the like formed in the inner wall of the inner cylinder part, the air flow resistance is reduced by suppressing the turbulence of the air flow compared to the conventional silencer, and the silencer is suppressed by suppressing the adhesion of foreign matter. The effect can be enhanced.

According to the invention which concerns on Claim 2, a silencer is further provided with the non-return valve provided in a communicating path. The check valve further includes a check valve that allows an air flow from the cylindrical space to the intake passage and suppresses an air flow from the intake passage to the cylindrical space.
Thereby, the backflow of the air to cylindrical space can be suppressed and the vacuum degree of cylindrical space can be maintained. Therefore, the silencing effect of the silencing device can be enhanced.

According to the invention of claim 3, the communication pipe includes a second imaginary plane in which an end portion of the communication passage on the side opposite to the cylindrical space includes an end surface of the intake passage opposite to the engine side of the compressor wheel. And a first virtual plane.
As a result, the end of the communication path opposite to the cylindrical space is positioned in the vicinity of the compressor wheel that is the negative pressure source, so that the negative pressure on the opposite side of the communication path from the cylindrical space is increased. Can do. For this reason, the force which attracts | sucks the air in cylindrical space can be raised, and the vacuum degree of cylindrical space can be raised.

According to the invention which concerns on Claim 4, an outer cylinder part has a cyclic | annular reinforcement part which protrudes to radial direction.
Thereby, the deformation | transformation of the outer cylinder part by the differential pressure of the pressure of a cylindrical space and the pressure of the radial direction outer side of an outer cylinder part can be suppressed.

The schematic diagram which shows the engine system to which the silencer of 1st Embodiment of this invention was applied. II-II sectional view taken on the line of FIG. The perspective view which shows the silencer of 1st Embodiment of this invention. The perspective view which shows the silencer of 2nd Embodiment of this invention.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows an example in which the intake device according to the first embodiment of the present invention is applied to an engine system of a vehicle. As shown in FIG. 1, the engine system 1 includes an intake pipe 10, an engine 30, an exhaust pipe 40, a supercharger 50, and a silencer 60.

  An intake passage 11 is formed inside the intake pipe 10. An intake port 12 is formed at one end of the intake pipe 10. An air filter 13 is provided on the intake pipe 12 side of the intake pipe 10. The air filter 13 collects foreign matter in the intake air. The other end of the intake pipe 10 is connected to the engine 30. Further, a throttle valve 14 is provided on the engine 30 side of the intake passage 11. The throttle valve 14 can adjust the amount of intake air supplied to the engine 30 by opening and closing the intake passage 11.

  The engine 30 has an intake port 33, an exhaust port 34, and four cylinders 32 in which a combustion chamber 31 is formed. The combustion chamber 31 communicates with the intake passage 11 in the intake pipe 10 via the passage in the intake port 33. In addition, the combustion chamber 31 communicates with an exhaust passage 41 in an exhaust pipe 40 to be described later via a passage in the exhaust port 34.

  The exhaust pipe 40 is connected to the exhaust port 34 of the engine 30. The end of the exhaust pipe 40 on the exhaust port 34 side is branched into four parts, and each end is connected to the exhaust port 34. An exhaust port 42 is formed at the end of the exhaust pipe 40 opposite to the exhaust port 34. The exhaust pipe 40 forms an exhaust passage 41 inside.

  The supercharger 50 is provided between the intake pipe 10 and the exhaust pipe 40. The supercharger 50 has a turbine wheel 52, a compressor wheel 51 and a shaft 53. The turbine wheel 52 is rotatably provided between the engine 30 and the exhaust port 42 in the exhaust passage 41. On the other hand, the compressor wheel 51 is rotatably provided between the air filter 13 and the throttle valve 14 in the intake passage 11. The shaft 53 connects the turbine wheel 52 and the compressor wheel 51. When the exhaust gas flows through the exhaust passage 41, the turbine wheel 52 rotates. Thereby, the compressor wheel 51 rotates. When the compressor wheel 51 rotates, the intake air is compressed by the compressor wheel 51 and supplied to the engine 30. That is, the supercharger 50 is a turbocharger that supercharges intake air to the engine 30. The intake air supercharged by the compressor wheel 51 generates noise due to pulsation.

The silencer 60 is provided between the compressor wheel 51 of the intake pipe 10 and the engine 30 in order to suppress noise of intake air supercharged by the compressor wheel 51.
The silencer 60 includes an inner cylinder part 61, an outer cylinder part 62, a first annular part 63, a second annular part 64, a communication pipe 65, and a check valve 66, and is formed in a cylindrical shape.

The inner cylinder portion 61 has a substantially cylindrical shape, and forms a part of the intake passage 11 between the compressor wheel 51 and the engine 30. Moreover, the inner wall of the inner cylinder part 61 is formed smoothly.
The outer cylinder part 62 is provided on the outer diameter side of the inner cylinder part 61 and is formed in a substantially cylindrical shape. Here, the outer cylinder part 62 is formed so that the inner diameter is larger than the outer diameter of the inner cylinder part 61 (see FIG. 2).
That is, the outer wall of the inner cylinder part 61 and the inner wall of the outer cylinder part 62 have a predetermined interval.

The first annular portion 63 is formed in an annular shape and closes an annular opening formed at the end portions of the inner cylinder portion 61 and the outer cylinder portion 62 on the engine 30 side.
The second annular portion 64 is formed in an annular shape and closes the openings at the end portions of the inner cylinder portion 61 and the outer cylinder portion 62 on the compressor wheel 51 side. Thereby, a substantially cylindrical tubular space 67 is formed between the inner tubular portion 61, the outer tubular portion 62, the first annular portion 63 and the second annular portion 64.

  One end of the communication pipe 65 is connected to the second annular portion 64 of the silencer 60, and the other end is connected between the compressor wheel 51 of the intake pipe 10 and the intake port 12. A communication path 650 is formed inside the communication pipe 65. The communication passage 650 communicates between the cylindrical space 67 and the compressor wheel 51 and the intake port 12 of the intake passage 11. Here, the opening on the silencer 60 side of the communication pipe 65 is referred to as an intake port 651, and the opening on the intake pipe 10 side of the communication pipe 65 is referred to as an exhaust port 652.

  In the case of the present embodiment, as shown in FIG. 1, the exhaust port 652 includes a first virtual plane S <b> 1 including an end surface 511 of the compressor wheel 51 on the engine 30 side in the intake passage 11, and an intake port 12 of the compressor wheel 51. It is located between the second virtual plane S2 including the end face 512 on the side.

  The check valve 66 is provided in the communication pipe 65 and includes a stopper portion 661, an urging member 662, a valve body 663, and a valve seat 664. The stopper portion 661 is fixed in the communication pipe 65, and the valve seat 664 is fixed in the communication pipe 65 closer to the suction port 651 than the stopper portion 661. The valve body 663 is provided between the valve seat 664 and the stopper portion 661 so as to be able to contact the valve seat 664. The urging member 662 is provided between the valve body 663 and the stopper portion 661 and urges the valve body 663 toward the valve seat 664 side. Here, a state in which the valve body 663 is in contact with the valve seat 664 is referred to as a “valve closed state”, and a state in which the valve body 663 and the valve seat 664 are separated from each other is referred to as a “valve open state”. Accordingly, the check valve 66 allows the air flow from the suction port 651 to the discharge port 652 and suppresses the air flow from the discharge port 652 to the suction port 651.

Subsequently, the operation of the silencer 60 of the present embodiment will be described.
In the present embodiment, the rotation of the compressor wheel 51 generates a negative pressure between the compressor wheel 51 and the intake port 12 in the intake passage 11. In particular, in the intake passage 11, the negative pressure between the first virtual plane S1 and the second virtual plane S2 becomes high. Here, the resultant pressure of the pressure between the first virtual plane S1 and the second virtual plane S2 in the intake passage 11 and the biasing force of the biasing member 662 of the check valve 66 is the pressure in the cylindrical space 67. When it becomes smaller, the check valve 66 is opened. At this time, the air in the cylindrical space 67 is sucked into the intake passage 11 by a negative pressure. Thereby, the cylindrical space 67 is reduced in air density and approaches a vacuum.

  The pressure in the cylindrical space 67 is based on the resultant pressure of the pressure between the first virtual plane S1 and the second virtual plane S2 in the intake passage 11 and the biasing force of the biasing member 662 of the check valve 66. When it becomes smaller, the check valve 66 is closed. At this time, the air flow between the cylindrical space 67 and the intake passage 11 is blocked, and the air flow from the intake passage 11 to the cylindrical space 67 is suppressed.

  In the present embodiment, a silencer 60 having a cylindrical space 67 is provided between the compressor wheel 51 and the engine 30 in the intake passage 11. The cylindrical space 67 is connected between the compressor wheel 51 and the intake port 12 in the intake passage 11 by a communication passage 650. Therefore, when negative pressure is generated between the compressor wheel 51 and the intake port 12 in the intake passage 11 due to the rotation of the compressor wheel 51, the air in the cylindrical space 67 is sucked into the intake passage 11. The cylindrical space 67 approaches a vacuum state by sucking out air, and the degree of vacuum increases. Thereby, it can suppress that the vibration of the inner cylinder part 61 is transmitted to the outer cylinder part 62, and it can suppress that the noise by the pulsation of the intake air supercharged by the compressor wheel 51 is emitted outside. In addition, since the inner wall of the inner cylinder portion 61 is formed smoothly, the air flow resistance is reduced by suppressing the turbulence of the air flow, and the silencing effect is suppressed by suppressing the adhesion of foreign matter, as compared with the conventional silencer. Can be increased.

  In the present embodiment, a check valve 66 is provided in the communication path 650. Thereby, the backflow of the air to the cylindrical space 67 can be suppressed, and the vacuum degree of the cylindrical space 67 can be maintained. Therefore, the silencing effect of the silencing device 60 can be enhanced.

  Furthermore, in the present embodiment, the discharge port 652 of the communication pipe 65 is opened between the first first virtual plane S1 and the second second virtual plane S2 in the intake passage 11. Thereby, the discharge port 652 is opened in the vicinity of the compressor wheel 51 which is a negative pressure source. For this reason, the negative pressure near the discharge port 652 can be increased. Therefore, the force for sucking air in the cylindrical space 67 can be increased, and the degree of vacuum of the cylindrical space 67 can be increased.

(Second Embodiment)
A silencer according to a second embodiment of the present invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st Embodiment, and description is abbreviate | omitted.
As shown in FIG. 4, the silencer 70 of the present embodiment has an annular reinforcing portion 71 that protrudes radially outward on the outer wall of the outer cylindrical portion 62.
Thereby, in this embodiment, the deformation | transformation of the outer cylinder part 62 by the pressure difference between the pressure of the cylindrical space 67 and the pressure of the radial direction outer side of the outer cylinder part 62 can be suppressed.

(Other embodiments)
In the above embodiment, a check valve is provided in the communication path. On the other hand, in other embodiment, it is good also as a structure which does not provide a check valve.
In the above embodiment, the communication pipe has an end portion on the opposite side to the cylindrical space of the communication passage between the end surface on the internal combustion engine side of the compressor wheel and the end surface on the opposite side to the internal combustion engine side in the intake passage. It is connected to the. On the other hand, in another embodiment, the communication pipe has an end portion on the opposite side to the cylindrical space of the communication passage, an end surface on the opposite side to the internal combustion engine side of the compressor wheel in the intake passage, and an intake port. It is good also as a structure connected between.
In the said embodiment, the reinforcement part protrudes in the radial direction from the outer wall of an outer cylinder part, and is formed. On the other hand, in another embodiment, the reinforcing portion may be formed so as to protrude radially inward from the inner wall of the outer cylinder portion.
Thus, the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the invention.

DESCRIPTION OF SYMBOLS 11 ... Intake passage 30 ... Engine 51 ... Compressor wheel 60, 70 ... Silencer 61 ... Inner cylinder part 62 ... Outer cylinder part 63 ... 1st annular part 64 ... -2nd annular part 65 ... Communication pipe 66 ... Check valve 67 ... Cylindrical space 71 ... Reinforcement part S1 ... 1st virtual plane S2 ... 2nd virtual plane 650 ...・ Communication passage

Claims (4)

A silencer that suppresses noise during supercharging by a compressor wheel that supercharges intake air to the internal combustion engine,
Of the intake passage through which intake air to the internal combustion engine flows, an inner cylinder part that forms a part between the compressor wheel and the internal combustion engine;
An outer cylindrical portion provided on the outer diameter side of the inner cylindrical portion, and having an inner diameter larger than the outer diameter of the inner cylindrical portion;
A first annular portion that closes an annular opening between one end of the inner tubular portion and one end of the outer tubular portion;
By closing the annular opening between the other end of the inner cylinder and the other end of the outer cylinder, the gap between the inner cylinder, the outer cylinder, and the first annular part A second annular portion forming a cylindrical space;
A communication pipe that forms a communication path that connects the cylindrical space and a first virtual plane including an end face of the compressor wheel on the internal combustion engine side of the intake passage to the opposite side of the internal combustion engine;
A silencing device comprising:   A check valve provided in the communication passage, allowing a flow of air from the cylindrical space to the intake passage, and further suppressing a flow of air from the intake passage to the cylindrical space; The muffler according to claim 1.   The communication pipe includes a second imaginary plane in which an end portion of the communication passage on the opposite side to the cylindrical space includes an end surface of the intake passage opposite to the internal combustion engine side of the intake passage, and The muffler according to claim 1, wherein the silencer is provided so as to be connected to the first virtual plane.   The silencer according to any one of claims 1 to 3, wherein the outer cylinder portion has an annular reinforcing portion protruding in a radial direction.

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