JP2008057528A - Engine intake structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine intake structure capable of introducing low-temperature outside air without mixing water, dust or the like thereinto, and of reducing intake noise. <P>SOLUTION: In this engine intake structure, an intake passage 2 making the engine communicate with the outside air is arranged in a fender space 1; the intake passage 2 is formed into a structure including an intake duct 10, and a sound-deadening part 12; one end of the intake duct 10 is made to communicate with the engine; the other end of the intake duct 10 is connected to the sound-deadening part 12; a sound-deadening member 16 provided for the sound-deadening part 12 is formed of a material having a sound deadening characteristic; the other end of the intake duct 10 is made to communicate with a windshield-side opening 24 through an intake passage 22 formed in the sound-deadening member 16; and the windshield-side opening 24 is formed between the rear end of an engine hood 6 in the vehicular longitudinal direction and the windshield 26. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention includes, for example, an engine intake structure that includes an intake path of an engine disposed in a fender space and prevents noise leaking indoors or outside while securing the intake air amount of the engine.

When high-temperature outside air is drawn into the engine, the intake air charging efficiency of the engine decreases, making it difficult to improve engine output. Therefore, the outside-air inlet communicating with the engine intake path introduces low-temperature outside air. It must be placed in a possible position.
In addition, if water, dust, or the like is introduced into the engine, the engine may break down. For example, the position where the outside air introduction port is disposed is, for example, a position where water is not introduced when traveling in a puddle. It is necessary to set it to a position where water, dust, etc. are not mixed in the outside air sucked in.

For example, an engine intake structure described in Patent Document 1 is an example in which the outside air inlet is disposed at a position where water, dust, or the like is not mixed into the outside air sucked into the engine. In this engine intake structure, an outside air introduction port communicating with an intake path is arranged in a fender space formed by being surrounded by a fender panel, an engine compartment panel, and an inner liner.
Japanese Patent No. 3622369 (FIG. 1)

However, the engine intake structure described in Patent Document 1 has a problem as described below because an outside air introduction port communicating with the intake path is arranged in a fender space formed by being surrounded by a fender panel or the like. May occur.
Since the inside of the fender space is surrounded by a fender panel or the like, there is often a case where a communication portion with the outside air is not formed or the volume is small, and the outside air may not be efficiently supplied into the fender space. is there. For this reason, there may be a problem that the engine intake amount is insufficient only with the outside air supplied into the fender space.

In addition, the intake sound generated in response to the intake operation of the engine is radiated into the fender space from the outside air inlet, and this radiated sound propagates into the vehicle interior and becomes manifest as unpleasant noise in the vehicle interior. Problems may occur.
The present invention has been made paying attention to the above-described problems, and an object of the present invention is to provide an engine intake structure capable of reducing intake noise while securing an engine intake amount.

In order to solve the above-described problems, the present invention provides an engine in which at least a part of an intake path that communicates the engine and outside air is disposed in a fender space formed by being surrounded by at least a fender panel and an engine compartment panel. An intake structure,
One end of the intake path communicates with the engine through an engine side opening that opens in the engine compartment panel, and the other end of the intake path is a rear end of the engine hood in the vehicle front-rear direction. Communicate with the outside air through the windshield side opening formed between the windshield,
The muffler for reducing the intake noise generated inside the fender space path is provided in at least a part of the fender space path disposed in the fender space in the intake path. An engine intake structure is provided.

  According to the present invention, one end of the intake path communicates with the engine, and the other end of the intake path communicates with the outside air through the windshield side opening, so that the outside air is efficiently transferred to the intake path. It becomes possible to introduce. Here, there is a concern that the intake noise increases when the efficiency of the introduction of the outside air into the intake path increases. However, at least a part of the fender space paths arranged in the fender space among the intake paths is changed to the fender. Since the silencer is configured to reduce the intake sound generated inside the space path, the intake sound can be reduced.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
(Constitution)
FIG. 1 is a view showing a part of a vehicle C provided with the engine intake structure of the present embodiment. In addition, in FIG. 1, the state which removed the fender panel is shown for description.
As shown in FIG. 1, in the engine intake structure of the present embodiment, a part of an intake path 2 that communicates an engine (not shown) and outside air is disposed in a fender space 1. In the following description, a part of the intake path 2, that is, a part of the intake path 2 that is disposed in the fender space 1 will be described as a path 4 in the fender space.

  The fender space 1 is a space formed by the engine hood 6, a fender panel (not shown), and an engine compartment panel 8 connected to the fender panel with the engine hood 6 closed. It communicates with outside air through a windshield side opening which will be described later. The fender space 1 is a space formed by being surrounded by the fender panel and the engine compartment panel 8 with the engine hood 6 opened.

The intake path 2 includes an intake duct 10 and a silencer 12.
The intake duct 10 is formed of a tubular member such as a pipe, for example, and has a cross-sectional shape that is elliptical, and a cross-sectional area that is the same between both end portions.
One end of the intake duct 10 communicates with the engine via an engine-side opening 14 opened in the engine compartment panel 8, and the other end of the intake duct 10 is connected to the silencer 12. . Therefore, the intake duct 10 constitutes a portion of the intake path 2 on the engine side.

The silencer 12 is configured as a part of the fender space path 4 and includes a sound absorbing member 16. The silencer 12 is interposed between the intake duct 10 and the windshield side opening, and constitutes the windshield side opening of the intake path 2.
The position where the silencer 12 is arranged is a position in the fender space 1 where the distance between the silencer 12 and the engine side opening 14 is longer than the distance between the silencer 12 and the windshield side opening. Yes. Further, the position where the muffler 12 is disposed is within the fender space 1, the fender space 1, the front fender space 18 that forms the front part in the front direction of the vehicle, and the rear side that forms the rear part in the front direction of the vehicle. It is arranged at a position to be isolated from the fender space 20.

  The sound absorbing member 16 is made of, for example, a material having sound absorbing characteristics such as urethane, and is provided with an intake passage 22. Further, the sound absorbing member 16 has a function of reducing intake sound generated inside the fender space path 4 by being formed of a material having sound absorbing characteristics. In the engine intake structure of the present embodiment, the case where the sound absorbing member 16 is formed of urethane having an open cell structure will be described as an example.

The intake passage 22 communicates the other end of the intake duct 10 with the windshield side opening and constitutes a part of the intake path 2. In addition, the intake passage 22 is formed in an elliptical cross-sectional shape, similar to the intake duct 10, and is formed so that the cross-sectional area is the same between both end portions.
Therefore, the intake path 2 including the intake duct 10 and the silencer 12 is formed so that the cross-sectional shape is elliptical between both ends, and the cross-sectional area is the same between both ends.

FIG. 2 is a diagram showing a configuration of the windshield side opening 24. In FIG. 2, as in FIG. 1, a state in which the fender panel is removed is shown for explanation.
As shown in FIG. 2, the windshield side opening 24 is formed between the rear end of the engine hood 6 in the vehicle front-rear direction and the windshield 26, and as shown by arrows in the drawing, the fender space Outside air can be introduced into 1.
A wiper motor 30 that drives the wiper 28 is disposed below the fender space 1.

3 is a cross-sectional view taken along line III-III in FIG.
As shown in FIG. 3, the sound absorbing member 16 is in contact with the wheel house protector 32, the fender panel 34 and the engine compartment panel 8.
The wheel house protector 32 is connected to the lower ends of the fender panel 34 and the engine compartment panel 8.
4 is an enlarged view of the inside and the periphery of the circle IV described in FIG.
As shown in FIG. 4, the sound absorbing member 16 is in contact with the other end of the intake duct 10 without a gap, and the intake duct 10 and the intake passage 22 communicate with each other without a gap so that both of the intake paths 2 are connected. Part.

  FIG. 5 is a diagram illustrating the muffling unit 12, FIG. 5A is a diagram illustrating the muffling unit 12 as viewed from the front in the vehicle front-rear direction, and FIG. 5B is a diagram illustrating the muffling unit 12. It is a figure which shows the state seen from the direction of the arrow B described in 5 (a). FIG. 5C is a diagram showing a state in which the muffler 12 is viewed from the rear in the vehicle front-rear direction, and FIG. 5D is a diagram of the muffler 12 indicated by an arrow D described in FIG. It is a figure which shows the state seen from the direction.

As shown in FIG. 5, the silencer 12 is formed so as to have a shape corresponding to the space shape of the fender space 1 as a whole.
An end portion of the intake passage 22 on the intake duct 10 side is formed on the front surface of the muffler portion 12 in the front-rear direction of the vehicle, opens toward the front of the front-rear direction of the vehicle, and faces the other end portion of the intake duct 10. ing. The end of the intake passage 22 on the side of the windshield side opening 24 is formed on the surface of the muffler 12 that contacts the engine compartment panel 8, opens toward the upper side of the vehicle, and faces the windshield side opening 24. is doing.

FIG. 6 is a diagram showing the configuration of the muffler 12.
As shown in FIG. 6, the silencer 12 includes a fender panel-side silencer 36 that contacts the fender panel 34 in the fender space 1, and an engine compartment panel-side silencer that contacts the engine compartment panel 8 in the fender space 1. 38.
Both the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 are made of, for example, a mold casting product, and are bonded together to form the silencer 12.

A fender panel-side recess 40 having a shape corresponding to the intake passage 22 is formed on a surface of the fender panel-side silencer 36 facing the engine compartment panel-side silencer 38.
An engine compartment panel side recess 42 and a silencer side opening 44 having a shape corresponding to the intake passage 22 are formed on the surface of the engine compartment panel side silencer 38 facing the fender panel side silencer 36.

FIG. 7 is a view of the state in which the silencer 12 is disposed in the fender space 1 as viewed from above the vehicle. In addition, in FIG. 7, the state which removed the engine hood is shown for description. Further, in FIG. 7, the direction in which the air taken into the engine moves is indicated by an arrow described as “intake direction”.
As shown in FIG. 7, the silencer side opening 44 is a position where the silencer 12 is opened toward the upper side of the vehicle in a state where the silencer 12 is disposed in the fender space 1 and communicates with the windshield side opening 24. Is formed.
In the state where the muffler 12 is formed by pasting the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 together, the fender panel-side recess 40 and the engine compartment panel-side recess 42 form the intake passage 22. (See FIG. 5).

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).
At this time, since the windshield-side opening 24 is formed between the rear end of the engine hood 6 in the vehicle front-rear direction and the windshield 26, water or water is introduced into the low-temperature outside air introduced into the intake passage 22. The possibility of dust and the like being mixed is reduced. In addition, a part of the outside air that hits the windshield 26 when the vehicle C is traveling efficiently moves to the windshield side opening 24, so that a large volume of outside air is introduced into the intake passage 22.

  Here, the engine forms a pressure source for generating an intake pulsation in the gas existing in the intake path 2 in accordance with the intake operation, and the intake pulsation constitutes an intake sound. The intake pulsation generated in association with the intake operation of the engine is a pressure fluctuation generated in the gas existing in the intake passage 2, and this pressure fluctuation is composed of pressure fluctuations of a plurality of frequencies. That is, the intake pulsation generated in association with the intake operation of the engine is composed of intake pulsations with a plurality of frequencies.

At this time, since the intake passage 22 is provided in the sound absorbing member 16 formed of a material having a sound absorption characteristic, the intake sound generated inside the fender space path 4 due to the intake operation of the engine is the sound absorption. The sound is absorbed and reduced by the member 16 (see FIG. 1).
In addition, the silencer 12 including the sound absorbing member 16 is located in the fender space 1 such that the distance between the silencer 12 and the engine-side opening 14 is longer than the distance between the silencer 12 and the windshield-side opening 24. (Refer to FIG. 1).

For this reason, it becomes possible to arrange the silencer 12 at a position where the intake pulsation is attenuated, and it is possible to improve the reduction efficiency of the intake sound. This is because the generation of the intake noise is caused by the intake pulsation caused by the intake operation of the engine. The longer the distance between the silencer 12 and the engine, the more the position of the silencer 12 attenuates the intake pulsation. This is because it becomes a position.
In addition, since the silencer 12 is arranged at the above position, the resonance frequency of the intake pulsation generated with the intake operation of the engine is low, and the air in the intake passage 22 has a high frequency that makes the passenger feel uncomfortable. While moving in the intake passage 22, the intake noise is reduced. This is because the longer the distance between the silencer 12 and the engine, the lower the frequency of the intake sound generated by resonance in the intake path 2.

The air introduced into the intake passage 22 moves into the intake duct 10 while the intake sound is absorbed and reduced by the sound absorbing member 16. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).
At this time, the sound absorbing member 16 is in contact with the other end of the intake duct 10 without a gap, and the intake duct 10 and the intake passage 22 communicate with each other without a gap. The air that moves to the outside is prevented from leaking outside the intake path 2 (see FIG. 4).

(Effects of the first embodiment)
(1) In the engine intake structure of the present embodiment, the other end of the intake path communicates with the outside air through the windshield side opening, and the windshield side opening is located behind the engine hood in the vehicle front-rear direction. It is formed between the end and the windshield.
For this reason, since it becomes possible to reduce the possibility that water, dust, etc. are mixed in the low temperature outside air introduced into the intake passage, the low temperature outside air, which is not mixed with water, dust, etc. It becomes possible to introduce into. Also, since the outside air efficiently moves to the windshield side opening, a large volume of outside air is introduced into the intake passage, and a large volume of outside air can be introduced into the intake path.
As a result, it is possible to prevent a reduction in the intake air charging efficiency of the engine, improve the engine output, and prevent engine failure. Further, it is possible to deal with a large displacement engine, and it can be applied to a vehicle type equipped with a large displacement engine.

(2) Further, in the engine intake structure of the present embodiment, the intake passage that constitutes a part of the intake path is provided in the sound absorbing member formed of the material having the sound absorption characteristics. Inhalation sound generated in this manner is absorbed and reduced by the sound absorbing member.
For this reason, it is possible to reduce the intake noise generated by the intake operation of the engine without shielding the inside of the fender space with a sound insulating material or the like. It becomes possible to prevent manifestation as unpleasant noise in the room.
As a result, both the noise problem and the intake air shortage problem can be solved.

(3) Further, in the engine intake structure of the present embodiment, the silencer has a longer distance between the silencer and the engine side opening in the fender space than the distance between the silencer and the windshield side opening. Placed in position.
For this reason, it is possible to arrange the silencer at a position where the intake pulsation is attenuated, and it is possible to improve the reduction efficiency of the intake sound. In addition, the resonance frequency of the intake pulsation generated with the intake operation of the engine is lowered, and the air in the intake passage moves in the intake passage while reducing the high-frequency intake noise that the passenger feels uncomfortable.
As a result, it is possible to efficiently reduce the intake sound and to prevent the unpleasant intake sound from being transmitted to the occupant, thereby improving the quality of the intake sound. .

(4) Further, in the engine intake structure of the present embodiment, the sound absorbing member is in contact with the wheel house protector, the fender panel, and the engine compartment panel.
For this reason, even if the intake duct vibrates with the intake operation of the engine, this vibration is suppressed, and noise caused by the vibration of the intake duct can be suppressed.
As a result, it is possible to improve the quietness when the engine is driven.

(5) Further, in the engine intake structure of the present embodiment, since the intake path is formed to have an elliptical cross-sectional shape, the flow of air moving in the intake path is rectified to a desired state. It becomes possible.
As a result, the intake efficiency of the engine can be improved, and the engine output can be improved.
(6) Further, in the engine intake structure of the present embodiment, since the intake path is formed so that the cross-sectional area is the same between both ends, the flow of air moving in the intake path is changed to a desired state. It becomes possible to rectify to.
As a result, the intake efficiency of the engine can be improved, and the engine output can be improved.

(7) Further, in the engine intake structure of the present embodiment, the sound absorbing member is in contact with the other end of the intake duct without a gap, and the intake duct and the intake passage communicate with each other without a gap. Air moving from the inside into the intake duct is prevented from leaking outside the intake path.
As a result, the intake efficiency of the engine can be improved, and the engine output can be improved.
(8) Further, in the engine intake structure of the present embodiment, the muffler includes a fender space, a front fender space that forms a front part in the front of the vehicle front-rear direction, and a rear part in the front of the vehicle front-rear direction. It arrange | positions in the position isolated to the back fender space to form.
As a result, since the intake sound generated in the front fender space is prevented from being propagated into the rear fender space, it is possible to improve the quietness when the engine is driven.

(Application examples)
(1) In the engine intake structure of the present embodiment, the intake duct 10 is formed to have an elliptical cross-sectional shape, but the configuration of the intake duct 10 is not limited to this. That is, for example, the intake duct 10 may be formed so that the cross-sectional shape is a perfect circle. In short, the intake duct 10 only needs to be formed so that the cross-sectional shape is circular.

(2) In the engine intake structure of the present embodiment, the intake duct 10 is formed so that the cross-sectional shape is elliptical and the cross-sectional shape is circular, but the configuration of the intake duct 10 is as follows. However, the present invention is not limited to this. That is, for example, the intake duct 10 may be formed so that the cross-sectional shape is a square. However, as in the engine intake structure of the present embodiment, forming the intake duct 10 to have a circular cross-sectional shape rectifies the flow of air moving in the intake duct 10 to a desired state. Is preferable.

(3) Further, in the engine intake structure of the present embodiment, the intake duct 10 is formed so that the cross-sectional area is the same between both ends, but the configuration of the intake duct 10 is not limited to this. . That is, the air intake duct 10 may be formed so that the cross-sectional area is different between both end portions.
(4) Further, in the engine intake structure of the present embodiment, the intake passage 22 is formed so as to have an elliptical cross-section like the intake duct 10, but the configuration of the intake passage 22 is limited to this. It is not a thing. That is, for example, the intake passage 22 may be formed so that the cross-sectional shape is a perfect circle. In short, the intake passage 22 only needs to be formed so that the cross-sectional shape is circular.

(5) Further, in the engine intake structure of the present embodiment, the intake passage 22 is formed so that the cross-sectional shape is elliptical and the cross-sectional shape is circular, similar to the intake duct 10, The configuration of the intake passage 22 is not limited to this. That is, for example, the intake passage 22 may be formed so that the cross-sectional shape is a square. However, as in the engine intake structure of the present embodiment, forming the intake passage 22 so that the cross-sectional shape is circular rectifies the flow of air moving in the intake passage 22 to a desired state. Is preferable.
(6) Further, in the engine intake structure of the present embodiment, the intake passage 22 is formed so that the cross-sectional area is the same between both end portions as in the intake duct 10, but the configuration of the intake passage 22 is the same. It is not limited. That is, the intake passage 22 may be formed so that the cross-sectional area is different between both end portions.

(7) In the engine intake structure of the present embodiment, the silencer 12 is separated from the muffler 12 and the windshield side opening 24 in the fender space 1 by the distance between the silencer 12 and the engine side opening 14. However, the present invention is not limited to this. That is, for example, the silencer 12 may be disposed in the fender space 1 at a position where the distance between the silencer 12 and the engine is shorter than the distance between the silencer 12 and the windshield side opening 24. Further, the silencer 12 may be arranged in the fender space 1 at a position where the distance between the silencer 12 and the engine is the same as the distance between the silencer 12 and the windshield side opening 24.

(8) Further, in the engine intake structure of the present embodiment, the silencer 12 is separated from the fender space 1 by the distance between the silencer 12 and the engine side opening 14. However, the present invention is not limited to this. That is, for example, when the portion of the intake duct 10 that is disposed between the engine and the engine compartment panel 8 is long, the silencer 12 is connected to the silencer 12 and the engine-side opening 14 in the fender space 1. May not be disposed at a position where the distance is longer than the distance between the muffler 12 and the windshield side opening 24. In short, the position where the muffler 12 is disposed may be a position where the distance between the muffler 12 and the engine is longer than the distance between the muffler 12 and the windshield side opening 24.

(9) In the engine intake structure of the present embodiment, the sound absorbing member 16 is brought into contact with the wheel house protector 32, the fender panel 34, and the engine compartment panel 8. However, the present invention is not limited to this. That is, for example, the sound absorbing member 16 may be brought into contact with at least two of the wheel house protector 32, the fender panel 34, and the engine compartment panel 8. Further, the sound absorbing member 16 may be separated from all of the wheel house protector 32, the fender panel 34, and the engine compartment panel 8.

(10) In the engine intake structure of the present embodiment, the sound absorbing member 16 is formed of urethane having an open cell structure. However, the present invention is not limited thereto, and the sound absorbing member 16 is formed of urethane having a semi-open cell structure. It may be formed. Further, for example, the fender panel side silencer 36 is formed of urethane having an open cell structure, and the engine compartment panel side silencer 38 is formed of urethane having a semi-open cell structure. The silencer 38 may be formed of a different material.
(11) In the engine intake structure of the present embodiment, the sound absorbing member 16 is formed of urethane. However, the present invention is not limited to this, and the sound absorbing member 16 is formed of an elastic material such as rubber having sound absorbing characteristics. May be. In short, the sound absorbing member 16 only needs to be formed of a material having sound absorbing characteristics.

(12) In the engine intake structure of the present embodiment, the other end of the intake duct 10 is connected to the silencer 12, and the intake duct 10 constitutes the engine side portion of the intake path 2, and the silencer 12 constitutes a portion of the windshield side opening 24 of the intake passage 2, but is not limited thereto. That is, for example, one end of the intake duct 10 communicates with the engine, the other end of the intake duct 10 communicates with the outside air, and the silencer 12 is formed between both ends of the intake duct 10. Good.
(13) In the engine intake structure of the present embodiment, the muffler 12 constitutes a part of the fender space path 4. However, the present invention is not limited to this. You may comprise 4 several places.

(Second embodiment)
(Constitution)
Next, a second embodiment of the present invention will be described.
FIG. 8 is a diagram showing the configuration of the engine intake structure of the present embodiment, and is a diagram showing the configuration of the muffler 12.
As shown in FIG. 8, the configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above except for the configuration of the silencer 12. That is, in the engine intake structure of the present embodiment, the shape of the sound absorbing member 16 included in the muffling unit 12 is cut into the integrated sound absorbing material M formed in a rectangular parallelepiped so that the space shape of the fender space 1 as a whole is cut. It is formed so as to have a shape according to. In FIG. 8, the shape of the sound absorbing member 16 formed by processing the sound absorbing material M is indicated by a broken line. The shape of the sound absorbing material M is not limited to a rectangular parallelepiped.
The sound absorbing member 16 includes an intake passage 22 that communicates the other end of the intake duct with the windshield side opening. The intake passage 22 is formed by punching the sound absorbing member 16.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Since the explanation about the operation of the engine intake structure of the present embodiment is the same as that of the first embodiment described above, a description thereof is omitted.
(Effect of the second embodiment)
(1) In the engine intake structure of the present embodiment, the shape of the sound absorbing member provided in the muffler is cut into the sound absorbing material as a whole so that the shape as a whole corresponds to the space shape of the fender space. Forming.
The sound absorbing member includes an intake passage that communicates the other end of the intake duct with the windshield side opening, and the intake passage is formed by subjecting the sound absorbing member to a drawing process.
As a result, as compared with the engine intake structure of the first embodiment described above, for example, equipment such as a mold used for mold casting is not required, so that it is possible to reduce the manufacturing cost of the silencer.

(Third embodiment)
(Constitution)
Next, a third embodiment of the present invention will be described.
FIG. 9 is a diagram showing a configuration of the engine intake structure of the present embodiment.
As shown in FIG. 9, the configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above, except for the configuration of the silencer 12.
The silencer 12 includes an intake passage 22, a plurality of through holes 46, and a sound absorbing member 16.
The intake passage 22 is formed of, for example, a tubular member such as a pipe, and communicates the other end of the intake duct 10 with the windshield side opening 24. Moreover, the intake passage 22 is formed so that the cross-sectional shape is elliptical and the cross-sectional area is the same between both end portions, as in the first embodiment.

The plurality of through holes 46 pass through the outer peripheral surface of the intake passage 22, and constitute a passage communication portion that connects the inside of the intake passage 22 and the outside of the intake passage 22.
The sound absorbing member 16 is disposed on the outer peripheral side of the intake passage 22 and covers each through hole 46. In addition, the sound absorbing member 16 is formed of a material having sound absorbing characteristics such as urethane, for example, as in the first embodiment described above.
10 is a cross-sectional view taken along line XX of FIG.
As shown in FIG. 10, the sound absorbing member 16 is separated from the outer peripheral surface of the intake passage 22.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).
At this time, since the intake passage 22 is formed of a tubular member, the flow of air moving in the intake passage 22 can be rectified to a desired state (see FIG. 9).

In addition, a plurality of through holes 46 penetrating the outer peripheral surface of the intake passage 22 are formed on the outer peripheral surface of the intake passage 22, and each through hole 46 connects the inside of the intake passage 22 and the outside of the intake passage 22. A communicating part in the passage for communicating is formed (see FIG. 9).
Further, on the outer peripheral side of the intake passage 22, a sound absorbing member 16 that covers each through hole 46 is disposed apart from the outer peripheral surface of the intake passage 22 (see FIG. 10).

Therefore, the volume expansion portion of the intake passage 22 is provided in the muffling portion 12 by each through hole 46 and the space formed between the intake passage 22 and the sound absorbing member 16. It is possible to reduce the ventilation resistance of the moving air (see FIG. 10).
Further, since the sound absorbing member 16 is formed of a material having sound absorbing characteristics, when the air moves in the intake passage 22, the intake sound generated along with the intake operation of the engine is absorbed by the sound absorbing member 16 and reduced. (See FIG. 9).
The air introduced into the intake passage 22 moves into the intake duct 10 while the intake sound is absorbed and reduced by the sound absorbing member 16. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).

(Effect of the third embodiment)
(1) In the engine intake structure of the present embodiment, since the intake passage provided in the silencer is formed by a tubular member, the flow of air moving in the intake passage can be rectified to a desired state. It has become.
As a result, the intake efficiency of the engine can be improved, and the engine output can be improved.

(2) Further, in the engine intake structure of the present embodiment, a plurality of through holes penetrating the outer peripheral surface of the intake passage are formed on the outer peripheral surface of the intake passage, and these through holes are connected to the inside of the intake passage. A mid-passage communicating portion that communicates with the outside of the intake passage is formed. In addition, a sound absorbing member that covers the communication portion in the passage is disposed on the outer peripheral side of the intake passage so as to be separated from the outer peripheral surface of the intake passage.
For this reason, the volume expansion portion of the intake passage is provided in the silencer portion by the space formed between the communication portion in the passage and the intake passage and the sound absorbing member, and the ventilation resistance of the air moving in the intake passage Can be reduced.
As a result, the intake efficiency of the engine can be improved, and the engine output can be improved. In addition, since it is possible to improve the volume expansion rate of the air sucked into the engine, it is possible to efficiently reduce the intake sound of the middle frequency as well as the high frequency intake sound that the passenger feels uncomfortable. Become.

(Application examples)
(1) In the engine intake structure of the present embodiment, the communication part in the passage is formed by the through hole 46 penetrating the outer peripheral surface of the intake passage 22, but the configuration of the communication part in the passage is limited to this. It is not a thing. That is, for example, a communication pipe that connects the inside of the intake passage 22 and the outside of the intake passage 22 may be attached to the outer peripheral surface of the intake passage 22, and the communication section in the passage may be formed by this communication pipe. In short, the configuration of the communication section in the passage may be a configuration that allows the inside of the intake passage 22 and the outside of the intake passage 22 to communicate with each other.
(2) Further, in the engine intake structure of the present embodiment, the communication part in the passage is formed by a plurality of through holes 46 that penetrate the outer peripheral surface of the intake passage 22, but the configuration of the communication part in the passage is limited to this. Instead, the communication part in the passage may be formed by one through hole 46 that penetrates the outer peripheral surface of the intake passage 22.

(Fourth embodiment)
(Constitution)
Next, a fourth embodiment of the present invention will be described.
FIG. 11 is a diagram showing the configuration of the engine intake structure of the present embodiment.
As shown in FIG. 11, the configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above except for the configuration of the silencer 12. That is, in the configuration of the engine intake structure of the present embodiment, the other end of the intake duct 10 in the intake path 2 is separated from the silencer 12, and between the intake duct 10 and the intake passage 22 is arranged. A gap I is formed. The other end of the intake duct 10 faces the end of the intake passage 22 on the intake duct 10 side.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).
The air introduced into the intake passage 22 moves into the intake duct 10 while the intake sound is absorbed and reduced by the sound absorbing member 16. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).

At this time, the other end of the intake duct 10 is separated from the muffler 12, and a gap I is formed between the intake duct 10 and the intake passage 22 (see FIG. 11).
For this reason, even if a liquid such as rainwater is mixed in the air introduced into the intake passage 22, the liquid drops downward from the gap I formed between the intake duct 10 and the intake passage 22. Thus, liquid such as rainwater is prevented from being mixed into the air moving from the intake passage 22 into the intake duct 10. In FIG. 11, the direction in which the liquid falls from the gap I downward in the vehicle is indicated by a downward arrow.
The other end of the intake duct 10 faces the end of the intake passage 22 on the intake duct 10 side. For this reason, among the air moving from the intake passage 22 into the intake duct 10, the amount of air moving outside the intake passage 2 from the gap formed between the intake duct 10 and the intake passage 22 is reduced. Is possible.

(Effect of the fourth embodiment)
(1) In the engine intake structure of the present embodiment, the other end of the intake duct is separated from the silencer, and a gap is formed between the intake duct and the intake passage.
For this reason, even if a liquid such as rainwater is mixed in the air introduced into the intake passage, the liquid will drop downward from the gap formed between the intake duct and the intake passage. .
As a result, it is possible to prevent a liquid such as rainwater from entering the air moving from the intake passage into the intake duct, thereby preventing engine failure.

(2) In the engine intake structure of the present embodiment, the other end of the intake duct faces the end of the intake passage on the intake duct side.
For this reason, among the air moving from the intake passage into the intake duct, it is possible to reduce the amount of air moving out of the intake passage from the gap formed between the intake duct and the intake passage.
As a result, the engine output can be improved, and the engine can be adapted to a large displacement engine, and can be applied to a vehicle type equipped with a large displacement engine.

(Application examples)
(1) In the engine intake structure of the present embodiment, the gap I is formed between the intake duct 10 and the intake passage 22; however, the present invention is not limited to this. 10 may be formed between the portion of the intake duct 10 on the windshield 26 side and the muffler 12. In short, it is only necessary to form a gap in the intake passage 2 between the fender space internal passage 4 and the intake passage 22 so that the liquid mixed in the air falls downward in the vehicle.

(Fifth embodiment)
(Constitution)
Next, a fifth embodiment of the present invention will be described.
The configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above, except for the configuration of the silencer 12.
FIG. 12 is a diagram illustrating the configuration of the muffler 12. 12A is a diagram showing a state in which the muffler 12 is viewed from the front in the vehicle front-rear direction, and FIG. 12B is a diagram of the muffler 12 indicated by an arrow B described in FIG. It is a figure which shows the state seen from the direction. FIG. 12C is a diagram showing a state where the muffling unit 12 is viewed from the rear in the vehicle front-rear direction, and FIG. 12D is a diagram of the muffling unit 12 indicated by an arrow D described in FIG. It is a figure which shows the state seen from the direction.
As shown in FIG. 12, the silencer 12 has a drain opening 48.
The drainage opening 48 communicates with the intake passage 22 and opens downward in the vehicle, and the opening area is formed to be smaller than the cross-sectional area of the intake passage 22.
Further, the drainage opening 48 opens downward in the vehicle and communicates the intake passage 22 and the rear fender space (see FIG. 1).
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).
At this time, the drainage opening 48 of the silencer 12 communicates with the intake passage 22 and opens downward of the vehicle (see FIG. 12).

For this reason, even if a liquid such as rainwater is mixed in the air introduced into the intake passage 22, this liquid falls from the drain opening 48 to the vehicle lower side, and the intake duct 22 enters the intake duct 22. It is prevented that liquids, such as rain water, mix in the air which moves into 10. In FIG. 12, the direction in which the liquid falls from the drain opening 48 to the vehicle lower side is indicated by a downward arrow.
In addition, the drainage opening 48 is formed so that the opening area thereof is smaller than the cross-sectional area of the intake passage 22 and communicates the intake passage 22 and the rear fender space (see FIG. 12). .

For this reason, the air moving from the intake passage 22 into the intake duct 10 is prevented from moving into the rear fender space through the drain opening 48. This is because the air pressure in the rear fender space is maintained at a positive pressure because the rear fender space is a closed space.
The air introduced into the intake passage 22 moves into the intake duct 10 while the intake sound is absorbed and reduced by the sound absorbing member 16. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).

(Effect of the fifth embodiment)
(1) In the engine intake structure of the present embodiment, the drain opening provided in the muffler communicates with the intake passage and opens downward in the vehicle.
For this reason, even if liquid such as rainwater is mixed in the air introduced into the intake passage, this liquid will drop from the vehicle downward to the air moving from the intake passage into the intake duct, The liquid such as rain water is prevented from being mixed.
As a result, engine failure can be prevented.

(2) Further, in the engine intake structure of the present embodiment, the drainage opening is formed such that the opening area is smaller than the cross-sectional area of the intake passage, and the intake passage and the rear fender space are separated from each other. Communicate.
For this reason, the air moving from the intake passage into the intake duct is prevented from moving into the rear fender space through the drain opening.
As a result, the engine output can be improved, and the engine can be adapted to a large displacement engine, and can be applied to a vehicle type equipped with a large displacement engine.

(Application examples)
(1) In the engine intake structure of the present embodiment, the drain opening 48 is configured to communicate the intake passage 22 and the rear fender space. However, the present invention is not limited to this. For example, The drain opening 48 may communicate the intake passage 22 and the outside of the vehicle. In short, the configuration of the drain opening 48 may be any configuration that can drop the liquid mixed in the air introduced into the intake passage 22 downward in the vehicle.

(Sixth embodiment)
(Constitution)
Next, a sixth embodiment of the present invention will be described.
The configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above, except for the configuration of the silencer 12.
FIG. 13 is a diagram illustrating the configuration of the muffler 12. 13A is a diagram showing a state in which the muffler 12 is viewed from the front in the vehicle front-rear direction, and FIG. 13B is a diagram of the muffler 12 indicated by an arrow B described in FIG. It is a figure which shows the state seen from the direction. Moreover, FIG.13 (c) is a figure which shows the state which looked at the muffling part 12 from the vehicle front-back direction back, FIG.13 (d) shows the muffling part 12 of the arrow D described in FIG.13 (c). It is a figure which shows the state seen from the direction.

As shown in FIG. 13, the intake passage 22 provided in the silencer 12 includes a windshield-side intake passage 50 disposed on the windshield (see FIG. 1) side and an engine-side intake passage disposed on the engine side. 52.
Since the windshield-side intake passage 50 and the engine-side intake passage 52 are separated from each other, a water drain gap 54 is formed between the windshield-side intake passage 50 and the engine-side intake passage 52.
A draining portion 56 formed at an acute angle is formed below the portion of the silencer 12 that forms the rear fender space side end of the windshield side intake passage 50.
The engine-side intake passage 52 is inclined so as to go forward in the vehicle front-rear direction, that is, toward the vehicle upward as it goes toward the intake duct (see FIG. 1).
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).
At this time, since the windshield side intake passage 50 and the engine side intake passage 52 provided in the intake passage 22 are separated from each other, a water drain gap 54 is provided between the windshield side intake passage 50 and the engine side intake passage 52. Is formed (see FIG. 13).

For this reason, even if a liquid such as rainwater is mixed in the air introduced into the intake passage 22, the liquid will fall from the drain gap 54 to the vehicle lower side, so that the windshield-side intake passage 50 and the engine It is possible to prevent liquid such as rainwater from entering the air moving to the side intake passage 52. In FIG. 13, the direction in which the liquid falls from the drain gap 54 downward to the vehicle is indicated by a downward arrow.
Further, a draining portion 56 formed at an acute angle is formed below the portion of the silencer 12 that forms the rear fender space side end portion of the windshield side intake passage 50 (see FIG. 13).
For this reason, the liquid mixed in the air moves into the rear fender space along the draining portion 56, and the water scavenging property of the air moving from the windshield side intake passage 50 to the engine side intake passage 52 is improved. .

The engine-side intake passage 52 is inclined so as to go upward in the vehicle as it goes forward in the vehicle front-rear direction.
For this reason, even if liquid is mixed in the air moving from the windshield-side intake passage 50 to the engine-side intake passage 52, the mixed liquid falls down the vehicle along the inclination of the engine-side intake passage 52. Thus, liquid is prevented from being mixed into the air moving from the engine side intake passage 52 to the intake duct.
The air that has moved from the engine side intake passage 52 into the intake duct 10 is sucked into the engine (see FIG. 1).

(Effects of the sixth embodiment)
(1) In the engine intake structure of this embodiment, the windshield-side intake passage and the engine-side intake passage provided in the intake passage are separated from each other, and water is drained between the windshield-side intake passage and the engine-side intake passage. A gap is formed.
For this reason, even if liquid such as rainwater is mixed in the air introduced into the intake passage, the liquid moves from the windshield-side intake passage to the engine-side intake passage in the middle of the drainage gap. Fall to.
As a result, it is possible to prevent a liquid such as rainwater from entering the air moving from the intake passage into the intake duct, thereby preventing engine failure.

(2) Further, in the engine intake structure of the present embodiment, a draining portion formed at an acute angle is formed below the portion of the silencer that forms the rear fender space side end portion of the windshield side intake passage. Yes.
For this reason, the liquid mixed in the air moves into the rear fender space along the drainage portion, and the water drainage of the air moving from the windshield side intake passage to the engine side intake passage is improved.
As a result, it is possible to prevent a liquid such as rainwater from entering the air moving from the intake passage into the intake duct, thereby preventing engine failure.

(3) Further, in the engine intake structure of the present embodiment, the engine-side intake passage is inclined so as to go upward in the vehicle as it goes forward in the vehicle front-rear direction.
For this reason, even if liquid is mixed in the air moving from the windshield-side intake passage to the engine-side intake passage, the mixed liquid falls down the vehicle along the inclination of the engine-side intake passage.
As a result, liquid is prevented from entering the air moving from the engine-side intake passage to the intake duct, and liquid such as rainwater is prevented from entering the air moving from the intake passage to the intake duct. Therefore, it is possible to prevent engine failure.

(Application examples)
(1) In the engine intake structure of the present embodiment, the water draining portion 56 formed at an acute angle is provided below the portion of the silencer 12 that forms the rear fender space side end portion of the windshield side intake passage 50. Although formed, it is not limited to this, The draining part 56 does not need to be formed.

(Seventh embodiment)
(Constitution)
Next, a seventh embodiment of the present invention will be described.
The configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above, except for the configuration of the silencer 12.
FIG. 14 is a diagram illustrating a configuration of the muffler 12. 14A is a diagram showing a state in which the muffler 12 is viewed from the front in the vehicle front-rear direction, and FIG. 14B is a diagram of the muffler 12 indicated by the arrow B described in FIG. 14A. It is a figure which shows the state seen from the direction. FIG. 14C is a diagram showing a state in which the silencer 12 is viewed from the rear in the vehicle front-rear direction, and FIG. 14D is a diagram of the silencer 12 indicated by the arrow D described in FIG. It is a figure which shows the state seen from the direction.

As shown in FIG. 14, the silencer 12 is provided with a drain slope 58 formed around the silencer side opening 44, that is, around the outside opening side of the intake passage 22. In addition, in FIG.14 (d), the part in which the drain inclination part 58 was formed is shown with the oblique line.
The opening on the outside air side of the intake passage 22 opens upward in the vehicle and communicates with the windshield-side opening 24.

FIG. 15 is a view of a state in which the silencer 12 is disposed in the fender space 1 as viewed from above the vehicle. In addition, in FIG. 15, the state which removed the engine hood is shown for description.
As shown in FIG. 15, the drainage inclined portion 58 is formed by cutting or the like, and is inclined rearward in the vehicle front-rear direction, that is, toward the vehicle lower side toward the windshield 26.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).
At this time, the muffling unit 12 includes a drainage inclined portion 58 formed around the muffling unit side opening 44. Moreover, the drainage inclined part 58 is formed by cutting etc., and it inclines so that it may go to the vehicle downward direction as it goes to the vehicle front-back direction back (refer FIG. 14).

For this reason, even if liquid such as rainwater is mixed in the air before being introduced into the intake passage 22, this liquid is rearward in the vehicle front-rear direction along the inclination of the drainage inclined portion 58 (in FIG. 15). , In the direction indicated by “water draining direction”), the vehicle falls downward, and liquid such as rainwater is prevented from being mixed into the air introduced into the intake passage 22. In FIG. 14, the direction in which the liquid moves rearward in the vehicle front-rear direction along the inclination of the drain inclination portion 58 is indicated by an arrow that is inclined downward toward the vehicle as it goes rearward in the vehicle front-rear direction.
The air introduced into the intake passage 22 moves into the intake duct 10 while the intake sound is absorbed and reduced by the sound absorbing member 16. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).

(Effect of the seventh embodiment)
(1) In the engine intake structure of the present embodiment, the muffling portion includes a drain slope portion formed around the opening on the outside air side of the intake passage. And the water drain inclination part inclines so that it may go to a vehicle downward direction as it goes to the vehicle front-back direction back.
For this reason, even if a liquid such as rainwater is mixed in the air before being introduced into the intake passage, the liquid moves to the rear in the vehicle front-rear direction along the inclination of the drain inclination portion, and then the vehicle It will fall downward.
As a result, it is possible to prevent liquid such as rainwater from entering the air introduced into the intake passage, thereby preventing engine failure.

(Eighth embodiment)
(Constitution)
Next, an eighth embodiment of the present invention will be described.
The configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above except for the configuration of the muffler. That is, in the engine intake structure of the present embodiment, the fender panel side silencer 36 and the engine compartment panel side silencer 38 are formed of materials having different sound absorption characteristics, and the peak frequency bands of the sound absorption rates are different from each other. (See FIG. 6).

In the present embodiment, as an example, the fender panel side silencer 36 is made of foamed rubber (sound absorption peak frequency band 315 Hz to 2500 Hz), and the engine compartment panel side silencer 38 is made of polyester (sound absorption rate). The case where the peak frequency band of 1000 Hz to 10000 Hz) is formed as a material will be described.
The fender panel-side recess 40 formed in the fender panel-side silencer 36 and the engine compartment panel-side recess 42 formed in the engine compartment panel-side silencer 38 together constitute the intake passage 22.

  FIG. 16 is a diagram illustrating a part of a method of manufacturing the members constituting the silencer, specifically, the fender panel side silencer and the engine compartment panel side silencer. FIG. 16A is a diagram showing a part of a method for producing a member constituting the silencer in the first embodiment, and FIG. 16B constitutes the silencer in the present embodiment. It is a figure which shows a part of manufacturing method of a member. In FIG. 16, two types of materials having different sound absorption characteristics are described as “material A” and “material B”.

  As shown in FIG. 16 (a), in the first embodiment, when manufacturing a member constituting the silencer, two sets of molds or a set of molds 60 having two spaces are used. Use. Then, by introducing a material having the same sound absorption characteristics ("material A" in the figure), the fender panel side silencer and the engine compartment panel side silencer are manufactured. FIG. 16 (a) shows a case where the fender panel side silencer and the engine compartment panel side silencer are manufactured using a set of molds 60 having two spaces.

  On the other hand, in this embodiment, when manufacturing the member which comprises a muffling part, as shown in FIG.16 (b), one set of metal mold | die 60 which has two places space is used. Then, by introducing materials having different sound absorption characteristics ("material A" and "material B" in the figure), the fender panel side silencer and the engine compartment panel side silencer are manufactured. In the present embodiment, as an example, a case where the fender panel side silencer is manufactured from the material A and the engine compartment panel side silencer is manufactured from the material B will be described.

FIG. 17 is a diagram showing a state of the members constituting the silencer of the present embodiment, specifically, the fender panel side silencer 36 and the engine compartment panel side silencer 38 as seen from the surfaces facing each other. is there.
When assembling the muffler, the portion indicated by hatching in FIG. 17, that is, the portion of the fender panel side muffling portion 36 that faces the engine compartment panel side muffling portion 38, excluding the fender panel side recess 40. Then, apply an adhesive. Then, the fender panel side silencer 36 and the engine compartment panel side silencer 38 are bonded together. Alternatively, an adhesive is applied to a portion of the surface of the engine compartment panel side silencer 38 that faces the fender panel side silencer 36 except for the engine compartment panel side recess 42. Then, the fender panel side silencer 36 and the engine compartment panel side silencer 38 are bonded together.

It should be noted that an adhesive is applied to both the engine compartment panel-side silencer 38 and the fender panel-side silencer 36, and the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 are bonded together to assemble the silencer. Also good.
Other configurations are the same as those of the first embodiment described above.
The fender panel-side silencer 36 and the engine compartment panel-side silencer 38 as described above constitute at least a plurality of sound absorbing member constituting parts constituting the intake passage 22.

Further, the fender panel side recess 40 as described above forms a first groove constituting the intake passage 22.
Further, the engine compartment panel side recess 42 as described above constitutes a second groove opposite to the first groove constituting the intake passage 22.
Further, the fender panel side silencer 36 as described above constitutes a first sound absorbing material in which a first groove is formed.
In addition, the engine compartment panel-side silencer 38 as described above constitutes a second sound-absorbing material formed of a material having a different sound-absorbing characteristic from that of the first sound-absorbing material, as well as a second groove.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).

At this time, at least members constituting the intake passage 22 in the silencer 12, specifically, the fender panel side silencer 36 and the engine compartment panel side silencer 38 are formed of materials having different sound absorption characteristics. The sound absorption coefficient peak frequency bands are different from each other.
For this reason, the air introduced into the intake passage 22 is sucked and reduced by the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 while absorbing and reducing intake sounds having different peak frequency bands of the sound absorption rate. Move into the duct 10. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).

(Effect of the eighth embodiment)
(1) In the engine intake structure of this embodiment, at least the members constituting the intake passage of the silencer, that is, the fender panel side silencer and the engine compartment panel side silencer are formed of materials having different sound absorption characteristics. ing.
For this reason, the muffler part on the fender panel side and the muffler part on the engine compartment panel side have mutually different peak frequency bands of the sound absorption coefficient, and the air introduced into the intake passage produces intake sounds with different peak frequency bands of the sound absorption coefficient. It moves into the intake duct while being absorbed and reduced.

As a result, the frequency range of the sound absorption rate can be improved, the intake sound can be efficiently reduced, and unpleasant intake sound can be prevented from being transmitted to the occupant. It becomes possible to improve the sound quality of the intake sound.
In addition, since it is possible to improve the frequency range of the sound absorption coefficient without changing the shape of the parts arranged around the silencer, the sound quality of the intake sound is improved without increasing the manufacturing cost. It becomes possible to make it.

(Application examples)
(1) In the engine intake structure of the present embodiment, the muffler is composed of the fender panel-side muffler 36 and the engine compartment panel-side muffler 38 formed of materials having different sound absorption characteristics. It is not limited to. That is, for example, the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 may be formed of a material having the same sound absorption characteristics. In this case, a semi-cylindrical sound absorbing member configuration that forms part of the intake passage 22 on the surface of the fender panel side recess 40 independently of the fender panel side silencer 36 or the engine compartment panel side silencer 38, for example. It is set as the structure provided with the part. And the material which forms the fender panel side silencing part 36 or the engine compartment panel side silencing part 38, and the material which forms a sound absorption member structure part are formed with a material from which a sound absorption characteristic differs mutually. In short, the intake passage 22 may be configured by a plurality of members, and at least two of the plurality of members may be formed of materials having different sound absorption characteristics.

(2) Further, in the engine intake structure of the present embodiment, the fender panel side silencer 36 is made of foamable rubber (sound absorption coefficient peak frequency band 315 Hz to 2500 Hz) as a material, and the engine compartment panel silencer 38. Is formed using polyester (peak frequency band of sound absorption rate: 1000 Hz to 10000 Hz) as a material, but is not limited thereto. That is, for example, the fender panel side silencer 36 is made of polyester (sound absorption peak frequency band 1000 Hz to 10000 Hz), and the engine compartment panel side silencer 38 is foamed rubber (sound absorption peak frequency band). 315 Hz to 2500 Hz) may be formed as a material. In short, the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 may be made of materials having different sound absorption characteristics, and the peak frequency bands of the sound absorption coefficient may be different from each other. The materials for forming the fender panel-side silencer 36 and the engine compartment panel-side silencer 38 are the above-mentioned foaming rubber (sound absorption peak frequency band 315 Hz to 2500 Hz), polyester (sound absorption peak frequency band 1000 Hz to In addition to 10000 Hz, for example, slab chip urethane foam (peak frequency band of sound absorption rate 400 Hz to 4000 Hz), polypropylene (peak frequency band of sound absorption rate 1000 Hz to 10000 Hz), and the like may be used.

(3) Further, in the engine intake structure of the present embodiment, the fender panel side silencer 36 is formed by molding only foaming rubber (peak frequency band of sound absorption coefficient 315 Hz to 2500 Hz), that is, using the same material. However, the configuration of the fender panel side silencer 36 is not limited to this. That is, the fender panel side silencer 36 may be divided into, for example, a front side and a rear side in the vehicle front-rear direction, and the front side and the rear side may be formed of materials having different sound absorption characteristics. The same applies to the engine compartment panel side silencer 38.

(Ninth embodiment)
(Constitution)
Next, a ninth embodiment of the present invention will be described.
The configuration of the engine intake structure of the present embodiment is the same as that of the first embodiment described above, except for the configuration of the silencer 12.
FIG. 18 is a diagram illustrating the configuration of the muffler 12.
As shown in FIG. 18, the silencer 12 of this embodiment is attached to the fender panel side silencer 36 and the engine compartment panel side silencer 38, and divides the intake passage 22 into three rows of passages. Two partition members 62a and 62b are provided. In FIG. 18, for the sake of explanation, the partition member 62 disposed above the two partition members 62 a and 62 b is defined as a partition member 62 a, and the two partition members 62 a and 62 b are disposed below. The partition material 62 arranged is a partition material 62b.

The partition material 62a and the partition material 62b are formed of materials having different sound absorption characteristics, and the peak frequency bands of the sound absorption coefficient are different from each other.
In the present embodiment, as an example, the partition material 62a is formed by using foamable rubber (sound absorption coefficient peak frequency band 315 Hz to 2500 Hz) as a material, and the partition material 62b is polyester (sound absorption coefficient peak frequency band 1000 Hz to 10,000 Hz). ) Will be described as a material.

FIG. 19 is a view showing a state in which the engine compartment panel side silencer 38 is viewed from a surface facing the fender panel side silencer.
As shown in FIG. 19, the partition members 62 a and 62 b are both formed in a plate shape extending along the air flow in the intake passage 22. Both ends of each partition member 62a, 62b are disposed with a gap between the silencer side opening 44 and the engine side opening 64 communicating with an intake duct (not shown). That is, each partition member 62a, 62b divides a part of the intake passage 22 into three rows of passages.
The intake passage 22 is the same as the intake passage 22 in the first embodiment described above, for example, by processing the fender panel side recess 40 and the engine compartment panel side recess 42 according to the volume of the partition members 62a and 62b. It has a volume of about.

20 is a view showing a method of attaching the partition member 62 to the fender panel side silencer and the engine compartment panel side silencer 38, and FIG. 20 (a) is a diagram showing the configuration of the partition member 62. (B) is a figure which shows the structure of the engine compartment panel side muffling part 38. FIG.
As shown in FIG. 20 (a), the partition member 62 has a plurality of fixing portions 66 formed in a columnar shape on the surface facing the fender panel side silencer and the engine compartment panel side silencer. In FIG. 20A, for the sake of explanation, the partition member 62 is represented as a single plate-like member that is not curved.

The fixing portion 66 may be integrally formed with the partition member 62 by insert molding or the like, for example. Further, for example, a hole may be provided in a surface of the partition member 62 facing the fender panel side silencer and the engine compartment panel side silencer, and the partition member 62 may be fixed to the partition member 62 by being inserted into the hole.
As shown in FIG. 20B, the engine compartment panel side recess 42 is formed with a plurality of fixing openings 68 having a shape into which the fixing portion 66 can be inserted. Further, although not particularly shown, a plurality of fixing holes are similarly formed in the concave portion on the fender panel side.
Then, by inserting each fixing portion 66 through each fixing opening 68, the partition member 62 is attached to the fender panel side silencing portion and the engine compartment panel side silencing portion 38, and the silencing portion 12 is configured.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the engine intake structure of this embodiment will be described. In the following description, the operations other than the muffling unit 12 are the same as those in the first embodiment described above, and therefore the description will focus on the operations of different parts.
When the vehicle C travels, that is, when the engine is driven, air that is taken into the engine is first introduced into the intake passage 22 that forms part of the intake path 2 through the windshield side opening 24. (See FIG. 7).

At this time, the partition member 62a and the partition member 62b are formed of materials having different sound absorption characteristics, and the peak frequency bands of the sound absorption coefficient are different from each other.
For this reason, the air introduced into the intake passage 22 moves into the intake duct 10 while absorbing and reducing intake sounds having different peak frequency bands of the sound absorption rate by the partition member 62a and the partition member 62b. Then, the air that has moved into the intake duct 10 is sucked into the engine (see FIG. 1).

Further, by inserting each fixing portion 66 through each fixing opening 68, the partition material 62 is attached to the fender panel side silencer and the engine compartment panel side silencer 38, thereby configuring the silencer 12.
For this reason, in the intake passage 22 where the change of the airflow is generated according to the operation of the throttle pedal (not shown), the change of the airflow caused by the change in the mounting state of the partition members 62a and 62b occurs. Is prevented. Therefore, it is possible to prevent the intake state of the engine from becoming unstable.

(Effects of the ninth embodiment)
(1) In the engine intake structure of the present embodiment, the two partition members that divide the intake passage into a plurality of rows of passages are formed of materials having different sound absorption characteristics. The peak frequency bands of are different.
For this reason, since the air introduced into the intake passage moves into the intake duct while absorbing and reducing intake sounds having different peak frequency bands of the sound absorption coefficient, the components arranged around the silencer The frequency range of the sound absorption coefficient can be improved without changing the shape or the like.
As a result, it is possible to efficiently reduce the intake sound without increasing the manufacturing cost, and it is possible to prevent the unpleasant intake sound from being transmitted to the occupant. Can be improved.

(Application examples)
(1) In the engine intake structure of this embodiment, the intake passage 22 is divided into three rows of passages by the two partition members 62a and 62b. However, the present invention is not limited to this. That is, for example, the intake passage 22 may be divided into four or more rows of passages by three or more partition members 62. In this case, at least two partition members 62 among the three or more partition members 62 may be formed of materials having different sound absorption characteristics.

(2) In the engine intake structure of the present embodiment, the intake passage 22 is divided into three rows of passages by the two partition members 62a and 62b. However, the present invention is not limited to this. That is, the intake passage 22 may be divided into two rows of passages by one partition member 62. In this case, for example, the partition member 62 is made of foamable rubber (sound absorption coefficient peak frequency band 315 Hz to 2500 Hz), and at least one of the fender panel side silencer 36 and the engine compartment panel side silencer 38 is used. Polyester (peak frequency band of sound absorption rate: 1000 Hz to 10000 Hz) is formed as a material. That is, the partition material 62 and at least one of the fender panel side silencer 36 and the engine compartment panel side silencer 38 are formed of materials having different sound absorption characteristics, and the peak frequency bands of the sound absorption coefficients are different from each other. The configuration is as follows.

(3) Further, in the engine intake structure of the present embodiment, the partition material 62a is made of foamable rubber (peak frequency band of sound absorption coefficient 315 Hz to 2500 Hz), and the partition material 62b is made of polyester (sound absorption coefficient). Although a peak frequency band of 1000 Hz to 10000 Hz is formed as a material, it is not limited to this. That is, for example, the partition material 62a is made of polyester (sound absorption peak frequency band 1000 Hz to 10000 Hz) and the partition material 62b is made of foamable rubber (sound absorption peak frequency band 315 Hz to 2500 Hz). It may be formed. In short, it is only necessary that the partition material 62a and the partition material 62b are made of materials having different sound absorption characteristics and that the peak frequency bands of the sound absorption coefficient are different from each other. In addition to the foamable rubber (sound absorption peak frequency band 315 Hz to 2500 Hz) and polyester (sound absorption peak frequency band 1000 Hz to 10000 Hz), the material forming the partition material 62 is, for example, slab chip urethane. Foam (sound absorption peak frequency band 400 Hz to 4000 Hz), polypropylene (sound absorption peak frequency band 1000 Hz to 10000 Hz), and the like may be used.

(4) Further, in the engine intake structure of the present embodiment, the partition member 62 has a plurality of fixing portions 66 formed in a columnar shape on a surface facing the fender panel side silencer and the engine compartment panel side silencer. ing. Moreover, although each fixing | fixed part 66 was set as the structure penetrated to the several opening part 68 for fixing formed in the engine compartment panel side recessed part 42, it is not limited to this.

  That is, for example, as shown in FIG. 21A, the partition material 62 is formed on the plate-like base material 70 using the same material as the partition material 62 having a smaller area than the base material 70. The sound absorbing material 72 is pasted and configured. And the part which protrudes from the sound-absorbing material 72 of the base material 70 is good also as the fixing | fixed part 66 formed in plate shape. In FIG. 21A, for the sake of explanation, the partition member 62 is represented as a single plate-like member that is not curved.

In this case, as shown in FIG. 21 (b), the engine compartment panel side recess 42 is formed with a shape through which the fixing portion 66 can be inserted, that is, a curved fixing opening 68, which is not particularly illustrated. Similarly, a curved fixing hole is formed in the concave portion on the fender panel side.
FIG. 21 is a view showing a modification of the method of attaching the partition member 62 to the fender panel side silencer and the engine compartment panel side silencer 38, and FIG. 21A shows the configuration of the partition member 62. FIG. 21B is a diagram showing the configuration of the engine compartment panel side silencer 38.

(5) Further, in the engine intake structure of the present embodiment, both ends of each of the partition members 62a and 62b are configured such that a part of the intake passage 22 is divided into three rows of passages. It is not limited. That is, for example, both ends of each partition member 62a, 62b are arranged without a gap between the silencer side opening 44 and the engine side opening 64, respectively. It is good also as a structure divided into the channel | path of the row | line | column.

(Example)
Using the engine intake structure of the present invention example and the engine intake structure of the comparative example, the sound pressure level of the intake sound in the vicinity of the windshield side opening was measured when the engine was driven.
As the engine intake structure of the example of the present invention, an engine intake structure having the same configuration as that described in the first embodiment of the present invention as shown in FIG. 1 is used.
As the engine intake structure of the comparative example, an engine intake structure having a structure without a muffler was used. Here, in the engine intake structure of the comparative example, an outside air introduction port communicating with the intake duct is arranged in the fender space.

  FIG. 22 is a diagram showing the results of measuring the sound pressure level of the intake sound in the vicinity of the windshield opening when the engine is driven, using the engine intake structure of the present invention example and the engine intake structure of the comparative example. The vertical axis in FIG. 22 indicates the sound pressure level of the intake sound near the windshield side opening (denoted as “sound pressure level [dB]” in the figure), and the scale is 10 dB. It has become. In addition, the horizontal axis of FIG. 22 indicates the height of a frequency (denoted as “frequency [Hz]” in the figure) that is generated as the engine is driven.

Next, the result of measuring the sound pressure level of the intake sound in the vicinity of the windshield side opening when the engine is driven will be described with reference to FIG. In FIG. 22, the result of measuring the sound pressure level using the engine intake structure of the present invention example is shown by a solid line, and the result of measuring the sound pressure level using the engine intake structure of a comparative example is shown by a broken line. Yes.
The sound pressure level of the intake sound near the windshield side opening was measured by arranging a microphone near the windshield side opening and detecting the sound pressure level of the intake sound using this microphone. The distance between the windshield side opening and the microphone was set to 50 mm.

As shown in FIG. 22, in the engine intake structure of the present invention example, the sound pressure level of the intake sound is reduced by an average of 8 dB, particularly in the high frequency band, as compared with the engine intake structure of the comparative example. In FIG. 22, the range in which the intake noise is reduced by the engine intake structure of the present invention compared to the engine intake structure of the comparative example is indicated by hatching.
In addition, as a result of measuring the sound pressure level of the intake sound introduced into the vehicle interior with the microphone at the driver's ear position in the driver's seat in the vehicle interior, the sound of the intake sound particularly in the high frequency band is measured. It was confirmed that the pressure level was reduced by about 2 dB.
From the above measurement results, it was confirmed that the engine intake structure of the example of the present invention has a higher intake noise reduction effect than the engine intake structure of the comparative example.

Next, using a silencer having the same configuration as that described in the eighth embodiment of the present invention (hereinafter referred to as “the silencer of the present invention”), a reverberation chamber method sound absorption coefficient characteristic experiment was performed. .
FIG. 23 is a diagram showing the results of a reverberation chamber method sound absorption coefficient characteristic experiment using the silencer of the eighth embodiment of the present invention. Note that the vertical axis in FIG. 23 indicates the sound absorption rate, and the horizontal axis in FIG. 23 indicates the high frequency generated as the engine is driven (indicated as “frequency [Hz]” in the figure). It shows.

  Next, with reference to FIG. 23, the results of a characteristic experiment of the reverberation chamber method sound absorption coefficient when the engine is driven will be described. In FIG. 23, the measurement result of the sound absorption coefficient characteristic of the material A is indicated by a solid line, and the measurement result of the sound absorption coefficient characteristic of the material B is indicated by a broken line. Further, in FIG. 23, the range in which the sound absorption rate is improved by the silencer of the present invention compared to the conventional silencer is indicated by hatching.

  As shown in FIG. 23, it was confirmed that the frequency range of the sound absorption coefficient is expanded in the silencer of the present invention compared to the conventional silencer. Therefore, by using the silencer of the present invention in an actual vehicle, the frequency range of the sound absorption rate when the engine is driven can be expanded, so that it is possible to solve the vehicle noise problem, improve the quality of the intake sound, and improve the quietness when the engine is driven. It was confirmed that there was.

It is a figure which shows a part of vehicle C provided with the engine intake structure of 1st embodiment of this invention. It is a figure which shows the structure of the windshield side opening part 24. FIG. It is the III-III sectional view taken on the line of FIG. It is an enlarged view of the inside of the circle IV described in FIG. 1, and its periphery. It is a figure which shows the muffler part. FIG. 3 is a diagram illustrating a configuration of a silencer 12. It is the figure which looked at the state which has arranged silencer 12 in fender space 1 from the vehicles upper part. It is a figure which shows the structure of the engine intake structure of 2nd embodiment of this invention, and is a figure which shows the structure of the muffling part 12. It is a figure which shows the structure of the engine intake structure of 3rd embodiment of this invention. FIG. 10 is a sectional view taken along line XX in FIG. 9. It is a figure which shows the structure of the engine intake structure of 4th embodiment of this invention. It is a figure which shows the structure of the engine intake structure of 5th embodiment of this invention, and is a figure which shows the structure of the muffling part 12. It is a figure which shows the structure of the engine intake structure of 6th embodiment of this invention, and is a figure which shows the structure of the muffling part 12. It is a figure which shows the structure of the engine intake structure of 7th embodiment of this invention, and is a figure which shows the structure of the muffling part 12. It is the figure which looked at the state which has arranged silencer 12 in fender space 1 from the vehicles upper part. It is a figure which shows a part of manufacturing method of the member which comprises the muffling part of 8th embodiment of this invention. It is a figure which shows the state which looked at the member which comprises the muffling part of 8th embodiment of this invention from the mutually opposing surface, respectively. It is a figure which shows the structure of the muffling part 12 of 9th embodiment of this invention. It is a figure which shows the state which looked at the engine compartment panel side muffler part 38 from the surface facing a fender panel side muffler part. It is a figure which shows the attachment method of the partition material 62 to the fender panel side silencer and the engine compartment panel side silencer. It is a figure which shows the modification of the attachment method of the partition material 62 to the fender panel side silencer and the engine compartment panel side silencer. It is a figure which shows the result of having measured the sound pressure level of the intake sound in the windshield side opening part vicinity at the time of engine drive using the engine intake structure of the example of this invention, and the engine intake structure of the comparative example. It is a figure which shows the result of having conducted the characteristic experiment of the reverberation room method sound absorption coefficient using the muffling part of 8th embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fender space 2 Intake path 4 Fender space path 6 Engine hood 8 Engine compartment panel 10 Intake duct 12 Silencer part 14 Engine side opening 16 Sound absorption member 18 Front fender space 20 Rear fender space 22 Intake path 24 Windshield side opening 26 Windshield 28 Wiper 30 Wiper motor 32 Wheel house protector 34 Fender panel 36 Fender panel side silencer 38 Engine compartment panel side silencer 40 Fender panel side recess 42 Engine compartment panel side recess 44 Silencer side opening 46 Through hole 48 Drain opening 50 Windshield side intake passage 52 Engine side intake passage 54 Drain gap 56 Drain portion 58 Drain slope portion 60 Mold 62 Partition material 64 Engine side Gap formed between the mouth portion 66 fixed portion 68 fixing opening 70 substrate 72 sound-absorbing material and C the vehicle M sound absorbing I intake duct and the intake passage

Claims (16)

An engine intake structure in which at least a part of an intake path communicating the engine and outside air is disposed in a fender space formed by being surrounded by at least a fender panel and an engine compartment panel,
The intake passage communicates with the engine through an engine-side opening having one end opened in the engine compartment panel, and the other end is between the rear end of the engine hood in the vehicle longitudinal direction and the windshield. Communicate with the outside air through the windshield side opening formed in the
Engine intake structure characterized in that at least a part of a path in the fender space arranged in the fender space among the intake paths is a silencer for reducing intake noise generated in the path in the fender space. .   2. The engine intake structure according to claim 1, wherein the silencer includes a sound absorbing member provided with an intake passage that constitutes a part of the path in the fender space.   The silencer includes an intake passage that forms a part of the fender space path, a mid-passage communication portion that is formed on the outer peripheral surface of the intake passage and connects the inside of the intake passage and the outside of the intake passage; The engine intake structure according to claim 1, further comprising: a sound absorbing member that is disposed on an outer peripheral side of the intake passage, covers at least the communication portion in the passage, and is separated from the outer peripheral surface of the intake passage. The intake passage is formed by a tubular member;
The engine intake structure according to claim 3, wherein the communication part in the passage is formed by one or a plurality of through holes penetrating an outer peripheral surface of the intake passage.   The engine intake structure according to any one of claims 1 to 4, wherein a distance between the silencer and the engine is longer than a distance between the silencer and the windshield side opening.   6. The engine intake structure according to claim 1, wherein the silencer is in contact with at least one of the fender panel and the engine compartment panel. 6.   The engine intake structure according to any one of claims 1 to 6, wherein a cross-sectional shape of at least a part of the intake path is circular.   The engine intake structure according to any one of claims 1 to 7, wherein a cross-sectional area of at least a part of the intake path is the same between the both end portions.   The engine intake structure according to any one of claims 1 to 8, wherein a gap is formed between the path in the fender space and the intake passage. The silencer includes a drain opening that communicates with the intake passage and opens downward in the vehicle.
10. The engine intake structure according to claim 2, wherein an opening area of the drain opening is smaller than a cross-sectional area of the intake passage. The intake passage includes a windshield-side intake passage disposed on the windshield side, and an engine-side intake passage disposed on the engine side,
A drainage gap is formed between the windshield-side intake passage and the engine-side intake passage,
The engine intake structure according to any one of claims 2 to 9, wherein the engine side intake passage is inclined so as to go upward in the vehicle as it goes forward in the vehicle front-rear direction. The opening on the outside air side of the intake passage opens upward in the vehicle,
The engine according to any one of claims 2 to 11, wherein a periphery of an opening on the outside air side of the intake passage is inclined so as to go downward in the vehicle as it goes rearward in the vehicle front-rear direction. Intake structure. The sound absorbing member includes a plurality of sound absorbing member constituting portions constituting the intake passage,
The engine intake structure according to any one of claims 2 to 12, wherein at least two of the plurality of sound absorbing member constituting portions are formed of materials having different sound absorption characteristics. The sound absorbing member includes a first sound absorbing material in which a first groove is formed, and a second sound absorbing material in which a second groove is formed,
The intake passage is formed by the first groove and the second groove facing each other,
The engine intake structure according to any one of claims 2 to 12, wherein the first sound absorbing material and the second sound absorbing material are formed of materials having different sound absorption characteristics. A plurality of partition members for dividing at least a part of the intake passage into a plurality of rows of passages;
The engine intake structure according to any one of claims 2 to 14, wherein at least two of the plurality of partition members are formed of materials having different sound absorption characteristics. Comprising one or more partition members that divide at least part of the intake passage into a plurality of rows of passages;
The engine intake structure according to any one of claims 2 to 14, wherein the partition member and the sound absorbing member are formed of materials having different sound absorption characteristics.

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