WO2022163274A1

WO2022163274A1 - Exhaust structure

Info

Publication number: WO2022163274A1
Application number: PCT/JP2021/048444
Authority: WO
Inventors: 石川正純
Original assignee: 三恵技研工業株式会社
Priority date: 2021-01-26
Filing date: 2021-12-25
Publication date: 2022-08-04
Also published as: JP7453736B2; JP2022114401A

Abstract

Provided is an exhaust structure 1 attached to an underfloor space of a vehicle 100, in which an exhaust muffler 2 and aerodynamic parts such as an under panel 3 and a diffuser 4 are formed from the same heat-resistant resin in an integrated way, the exhaust muffler 2 is formed into a flat shape extending substantially horizontally, and the entire exhaust structure 1 is formed into a flat shape extending substantially horizontally. With this arrangement, the number of parts installed under the floor of the vehicle can be reduced to attain an increase in the efficiency of parts attachment work and a reduction in manufacturing costs, creation of a wasted space in the underfloor layout of the vehicle can be suppressed, and the degree of freedom of the underfloor layout of the vehicle can be increased.

Description

Exhaust structure

The present invention relates to an exhaust structure provided with an exhaust muffler attached to the underfloor space of a vehicle.

Exhaust mufflers, which are installed in the underfloor space of a vehicle and discharge the exhaust generated by the internal combustion engine of the vehicle to the outside, are generally made of heat-resistant metal such as stainless steel because the exhaust gas circulating is hot. However, it is also possible to form the exhaust muffler with a heat-resistant resin as in Patent Document 1. The exhaust muffler of Patent Document 1 is constructed by attaching a layered structure of a heat-resistant material to the inner surface of a muffler body formed of a heat-resistant resin or a mixture of a heat-resistant resin and an inorganic substance.

Furthermore, in Patent Document 1, heat-resistant resins used in exhaust mufflers are selected from epoxy resins, phenol resins, silicone resins, unsaturated polyester resins, diallyl phthalate resins, melamine resins, and thermosetting polycarbodiimide resins. At least one thermosetting resin or at least one thermoplastic resin selected from polyamide resins, polyester resins, polyphenylene sulfide resins, thermoplastic fluororesins, polysulfone resins and polyphenylene ether resins is used. is disclosed.

JP-A-1-92507

By the way, in recent years, from the perspective of reducing air resistance and improving the fuel efficiency of automobiles, aerodynamic parts that control the flow of air, such as underpanels and diffusers, have been installed in the underfloor space of vehicles. Such aero parts are usually made of resin in order to reduce the weight of the vehicle. In addition, the exhaust muffler, which is also installed in the underfloor space of the vehicle, becomes hot due to the high temperature exhaust flow, so an insulator (heat shield plate) is installed between the exhaust muffler and aero parts to shield heat, and the exhaust muffler It is arranged to secure a gap between and aero parts.

However, with a structure in which a separate insulator is installed between the exhaust muffler and the aero parts, the number of parts increases, leading to a decrease in the efficiency of parts installation work and an increase in manufacturing costs. In addition, the structure in which a gap is secured between the exhaust muffler and the aero parts requires an extra space, and there is a problem that the degree of freedom of the underfloor layout of the vehicle is reduced.

The present invention is proposed in view of the above problems, and is capable of reducing the number of parts installed under the floor of a vehicle, improving the efficiency of parts mounting work, reducing manufacturing costs, and providing an underfloor layout of the vehicle. To provide an exhaust structure capable of suppressing the occurrence of wasted space in a vehicle and improving the degree of freedom of the underfloor layout of a vehicle.

An exhaust structure according to the present invention is attached to an underfloor space of a vehicle, and is characterized in that an exhaust muffler and at least one kind of aero parts are integrally formed of the same synthetic resin. Preferably, the synthetic resin is a heat-resistant resin.
According to this, it is possible to reduce the number of insulators (heat shielding plates) installed between the exhaust muffler and the aero parts, and it is possible to reduce the number of parts installed under the floor of the vehicle. Furthermore, there is no need to attach the aero parts integrated with the exhaust muffler separately, and they can be attached in the same mounting process. Therefore, it is possible to improve the efficiency of the component mounting work and reduce the manufacturing cost. In addition, by integrating the exhaust muffler and aero parts, it is possible to suppress unevenness in the underfloor space in the height direction, etc., compared to the case where they are separate members. It promotes control and reduction of air resistance, and can improve aerodynamic characteristics. Therefore, it is possible to improve the fuel efficiency and running stability of the automobile. In addition, since the space to be secured between the exhaust muffler and the aero parts can be reduced, it is possible to suppress the occurrence of wasted space in the underfloor layout of the vehicle and improve the flexibility of the underfloor layout of the vehicle. . In addition, by making the exhaust structure integrally formed of the same synthetic resin, the weight of the aero parts integrated with the exhaust muffler and the weight of the vehicle can be reduced, further improving the fuel efficiency of the vehicle. can.

The exhaust structure of the present invention is characterized in that the exhaust muffler is formed in a flat shape extending substantially horizontally, and the entirety is formed in a flat shape extending substantially horizontally.
According to this, by adopting a flat exhaust structure that extends substantially horizontally as a whole, unevenness in the height direction in the underfloor space can be greatly suppressed, and the unevenness can be greatly suppressed to reduce the amount of air flowing under the floor. Desired control and reduction of air resistance can be further promoted, and aerodynamic characteristics can be dramatically improved.

In the exhaust structure of the present invention, the exhaust muffler and the under panel, which is the aero part, are integrally formed of the same synthetic resin, and the exhaust muffler is disposed below the under panel and under the under panel. It is characterized in that it is positioned substantially in the center of the width direction and extends in the front-rear direction.
According to this, the number of insulators installed between the exhaust muffler and the under panel can be reduced, and the number of parts installed under the floor of the vehicle can be reduced. Furthermore, the need to attach the exhaust muffler and the under panel separately is eliminated, and they can be attached in the same mounting process. In addition, by integrating the exhaust muffler and the under panel, it is possible to suppress unevenness in the underfloor space in the height direction, etc., compared to the case where these are separate members. It promotes control and reduction of air resistance, and can improve aerodynamic characteristics. Furthermore, by arranging the exhaust muffler of the exhaust structure under the under panel and extending in the front-rear direction at approximately the center of the width direction of the under panel, the exhaust gas flows under the floor in a balanced manner on the left and right sides of the vehicle. More desirable control of the air becomes possible, and the running stability and operability of the automobile can be improved.

In the exhaust structure of the present invention, the exhaust muffler and the diffuser, which is the aero part, are integrally formed of the same synthetic resin, and the exhaust muffler is disposed between a pair of left and right diffuser portions constituting the diffuser. characterized in that it extends to
According to this, the number of insulators installed between the exhaust muffler and the diffuser can be reduced, and the number of parts installed under the floor of the vehicle can be reduced. Furthermore, the exhaust muffler and diffuser do not have to be installed separately, and can be installed in the same installation process. In addition, by integrating the exhaust muffler and diffuser, it is possible to suppress unevenness in the underfloor space in the height direction, etc., compared to the case where they are separate members. It can promote the reduction of air resistance and improve aerodynamic characteristics. Furthermore, by extending the exhaust muffler of the exhaust structure back and forth between the pair of left and right diffuser parts that constitute the diffuser, it is possible to control the air flowing under the floor in a balanced manner on the left and right sides of the vehicle. It is possible to improve the running stability and operability of the automobile.

In the exhaust structure of the present invention, the exhaust muffler and the aero parts such as the under panel and the diffuser are integrally formed of the same synthetic resin, the diffuser is continuously provided on the rear side of the under panel, and the exhaust A muffler is arranged on the lower side of the under panel, is positioned substantially at the center in the width direction of the under panel, and extends forward and backward, and extends forward and backward between a pair of left and right diffuser portions that constitute the diffuser. It is characterized by being formed in a flat shape extending substantially horizontally as a whole.
According to this, insulators installed between the exhaust muffler and the under panel and between the exhaust muffler and the diffuser can be reduced, and the number of parts installed under the floor of the vehicle can be reduced. Furthermore, it is no longer necessary to install the exhaust muffler, the under panel and the diffuser separately, and these three parts can be installed in the same installation process. In addition, by integrating the exhaust muffler, the under panel, and the diffuser, and creating a flat exhaust structure that spreads out substantially horizontally as a whole, it is possible to further suppress unevenness in the underfloor space in the height direction, etc. By suppressing unevenness, desirable control of air flowing under the floor and reduction of air resistance can be further promoted, and aerodynamic characteristics can be dramatically improved. Furthermore, the exhaust muffler of the exhaust structure is arranged below the under panel, positioned substantially at the center in the width direction of the under panel, and extends forward and backward, and between a pair of left and right diffuser parts constituting the diffuser. By extending in the front-rear direction, it is possible to control the air flowing under the floor in a balanced manner on the left and right sides of the vehicle, thereby improving the running stability and operability of the vehicle. Furthermore, the air flowing from the under panel to the diffuser can be rectified, favorable diffusion can be promoted, and the downforce can be increased to enhance the grip.

The exhaust structure of the present invention is characterized in that the synthetic resin is polypropylene.
According to this, the manufacturing cost of the exhaust structure can be reduced by using polypropylene, which is a general-purpose plastic. In addition, it is possible to obtain an exhaust structure that is resistant to acid and alkali and does not easily absorb water, and that is less susceptible to condensed water or the like. Also, since polypropylene is hard to break, the effect of preventing breakage of the synthetic resin exhaust structure can be enhanced.

According to the exhaust structure of the present invention, it is possible to reduce the number of parts installed under the floor of the vehicle, improve the efficiency of the parts mounting work, and reduce the manufacturing cost. The occurrence of this can be suppressed, and the degree of freedom in the underfloor layout of the vehicle can be improved.

The perspective view which looked the exhaust structure of embodiment by this invention from the lower side. The perspective view which looked the exhaust structure of embodiment from the upper side. (a) is a transverse explanatory view of a sub-silencer portion in the exhaust structure of the embodiment; (b) is a transverse explanatory view of the main silencer portion in the exhaust structure of the embodiment; FIG. 2 is a bottom view of the vehicle to which the exhaust structure of the embodiment is attached; FIG. 4 is a perspective explanatory view illustrating attachment of the exhaust structure of the embodiment to a member to be connected; FIG. 4 is an explanatory diagram illustrating the relationship between a vehicle to which the exhaust structure of the embodiment is attached and an existing exhaust muffler;

[Exhaust structure of embodiment]
An exhaust structure 1 according to an embodiment of the present invention is fixed to a bottom portion 101 of a vehicle 100 and arranged in an underfloor space to be attached. As shown in FIGS. , and the diffuser 4, which is an aeropart, are integrally formed from the same synthetic resin, and the whole is formed in a flat shape that extends substantially horizontally.

Although it is possible to use a suitable synthetic resin for the exhaust structure 1 within an applicable range, it is preferable to use a heat-resistant resin. Moreover, it is preferable to use polypropylene as a specific material of the synthetic resin. The exhaust structure 1 is integrally formed by injection molding using the same heat-resistant synthetic resin material such as polypropylene, or by injection-molding required constituent members using the same heat-resistant synthetic resin material such as polypropylene. It is preferable to integrally form such as by welding other constituent members.

The exhaust muffler 2 is formed in a flat shape extending substantially horizontally, and is formed in a cylindrical shape near a flange 21 located at the upstream end and in the vicinity of the flange 21, and is formed in a flat cylindrical shape on the downstream side thereafter. An exhaust pipe 22 located upstream, a flat sub-silencer 23 provided downstream of the exhaust pipe 22, a flat cylindrical exhaust pipe 24 provided downstream of the sub-silencer 23, and the exhaust pipe 24. A flat-shaped main silencer 25 which is provided on the downstream side and also functions as a tail end. The flattened sub-silencer 23 and main silencer 25 are wider than the flattened

tubular exhaust pipes

22 and 24 .

The sub-silencer 23 is formed wider than the upstream exhaust pipe 22 and the downstream exhaust pipe 24 so as to protrude to both sides, and is approximately the same as the upstream exhaust pipe 22 and the downstream exhaust pipe 24. formed at the same height. Inside the sub-silencer 23, as shown in FIG. 3A,

internal partition walls

231 and 231 are formed at positions substantially corresponding to the side walls on both sides of the

exhaust pipes

22 and 24 to partition the internal space. A through-hole group 232 for expanding the exhaust gas is formed in the partition wall 231 .

The main silencer 25 is formed wider than the exhaust pipe 24 on the upstream side so as to protrude to both sides. Inside the main silencer 25, as shown in FIG. 3B,

internal partition walls

251, 252, and 253 are formed to bypass and circulate the exhaust gas. The exhaust gas is repeatedly expanded and interfered inside the main silencer 25 to muffle the sound, and is discharged from the main silencer 25 to the outside. In the illustrated example, a plurality of mounting holes are formed in the main silencer 25 so as to be isolated from the internal space. The exhaust muffler 2 is attached to the vehicle bottom portion 101 by fixing the portion so as to be embedded in a member to be attached to the vehicle bottom portion 101 (see FIG. 4).

The under panel 3 is formed in a substantially rectangular flat plate shape in plan view, and also has a function as a protective component. It is provided so as to be located in the center and extend forward and backward. On the under panel 3 of the illustrated example, rectifying ridges 31 that enhance the rectifying effect are formed so as to protrude downward so as to extend in the longitudinal direction of the vehicle. and are arranged on both sides of the exhaust muffler 2 .

A plurality of mounting holes are formed in predetermined locations of the under panel 3, and fasteners 32 such as screws, bolts or clips are inserted through the respective mounting holes, and the tip of the fastener 32 is attached to the vehicle bottom 101. The under panel 3 and the exhaust muffler 2 are attached to the vehicle bottom portion 101 by being fixed so as to be embedded in the member (see FIG. 4). A member to be attached to which the under panel 3 is fixed by the fastener 32 can be an appropriate member arranged on the bottom portion 101 of the vehicle 100 .

The diffuser 4 is connected to the rear side of the under panel 3, and is composed of a pair of left and

right diffuser portions

4a and 4b which are substantially rectangular in plan view. The exhaust muffler 2 extends forward and backward between the

diffuser portions

4a and 4b. provided to exist. Straightening plates 41 that enhance the straightening effect are formed in the front portions of the illustrated

diffuser portions

4a and 4b so as to extend in the longitudinal direction of the vehicle, and the straightening plates 41 are formed in the

diffuser portions

4a and 4b. They are arranged at intervals in the width direction. In addition, at the rear of the

diffuser portions

4a and 4b of the illustrated example, an inclined plate 42 which is gradually inclined upward toward the rear is provided to facilitate attachment to the rear end portion of the vehicle bottom portion 101 which is inclined upward toward the rear. ing. A horizontal plate 43 is provided on the lower side of the inclined plate 42 so as to face it, and the airflow rectified by the horizontal plate 43 is smoothly led rearward.

A plurality of mounting holes are formed at predetermined positions of the

diffuser portions

4a and 4b, and fasteners 44 such as screws, bolts, or clips are inserted through the respective mounting holes, and the distal end portions of the fasteners 44 are attached to the vehicle bottom portion 101. The

diffuser portions

4a and 4b or the diffuser 4 and the exhaust muffler 2 are attached to the vehicle bottom portion 101 by being embedded in the attached member and fixed (see FIG. 4). The attached member to which the

diffuser portions

4 a and 4 b are fixed by the fastener 44 can be an appropriate member arranged on the bottom portion 101 of the vehicle 100 . In the illustrated example, mounting holes and fasteners 44 are provided in mounting plate portions protruding outward from the

diffuser portions

4a and 4b.

Insertion holes 211 are formed in the flange 21 at the upstream end of the exhaust muffler 2 in the exhaust structure 1 at intervals in the circumferential direction. A flange 201 is also provided at the rear end of a substantially tubular connected member 200 connected to the exhaust muffler 2, and insertion holes 202 are also formed in the flange 201 at intervals in the circumferential direction. The exhaust muffler 2 and the connected member 200 align the insertion hole 211 and the insertion hole 202 and abut the flange 21 and the flange 201, and the male threaded portion of the bolt 301 is inserted through the insertion hole 202 and the insertion hole 211 communicating with each other. By screwing a nut 302 onto this male threaded portion, it is fixedly connected (see FIG. 5).

The connected member 200 connected to the exhaust muffler 2 is suitable within the scope of the present invention, for example, an exhaust cooling device or a downstream pipe fixedly connected to the downstream side thereof, or an exhaust cooling device or the downstream side or fixedly connected to the catalytic converter or downstream thereof, or the like. When the exhaust structure 1 and the exhaust muffler 2 are installed downstream of an exhaust cooling device such as a heat exchanger that exchanges heat with cooling water, and the temperature-lowered exhaust is circulated, synthetic resin such as heat-resistant resin This is preferable because the exhaust structure 1 and the exhaust muffler 2 can be easily formed. In addition, the configuration of fixing and connecting the exhaust muffler 2 to the connected member 200 is appropriate other than the fastening of the bolt 301 and the nut 302, and it is also possible to fix it by adhesion or the like. is made of a metal material such as stainless steel, it is preferable to use fasteners such as fastening bolts 301 and nuts 302, screwing with tapping screws, or the like to fix and connect them.

According to the exhaust structure 1 of the present embodiment, insulators (heat shielding plates) installed between the exhaust muffler 2 and the under panel 3 and between the exhaust muffler 2 and the diffuser 4 can be reduced. It is possible to reduce the number of parts installed under the floor of the Furthermore, the exhaust muffler 2, the under panel 3, and the diffuser 4 need not be attached separately, and these three parts can be attached in the same attachment process. Therefore, it is possible to improve the efficiency of the component mounting work and reduce the manufacturing cost.

In addition, the gap secured between the exhaust muffler 2 and the under panel 3, which is an aero part, and the gap secured between the exhaust muffler 2 and the

diffuser portions

4a, 4b, which are aero parts, can be reduced. It is possible to suppress the occurrence of wasted space in the underfloor layout of the vehicle 100 and improve the degree of freedom in the underfloor layout of the vehicle 100 . In addition, by making the exhaust structure 1 integrally formed of the same synthetic resin, the weight of the aero parts integrated with the exhaust muffler 2 and the weight of the vehicle 100 can be reduced, and the fuel efficiency of the automobile can be greatly improved. can be enhanced.

In addition, by integrating the exhaust muffler 2, the under panel 3, and the diffuser 4, and forming a flat exhaust structure 1 that spreads out substantially horizontally as a whole, unevenness in the underfloor space in the height direction, etc. is further suppressed. By suppressing unevenness, desirable control of air flowing under the floor and reduction of air resistance can be further promoted, and aerodynamic characteristics can be dramatically improved. Furthermore, the exhaust muffler 2 of the exhaust structure 1 is arranged below the under panel 3 and extends frontward and rearward at substantially the center of the under panel 3 in the width direction. By extending back and forth between the

diffuser portions

4a and 4b, more desirable control of the air flowing under the floor of the vehicle 100 can be achieved, and the running stability and operability of the vehicle can be improved. be able to. Furthermore, the air flowing from the under panel 3 to the diffuser 4 can be rectified, favorable diffusivity can be promoted, and the downforce can be increased to enhance the grip.

In addition, by forming the flat exhaust structure 1 that extends substantially horizontally as a whole, and by arranging and mounting this exhaust structure 1 in the space under the floor of the vehicle 100, as shown in FIG. Compared to installing and installing in the underfloor space, it is possible to greatly reduce unevenness in the height direction in the underfloor space. and dramatically improve aerodynamic characteristics.

Further, when polypropylene is used as the same synthetic resin that constitutes the exhaust structure 1, the manufacturing cost of the exhaust structure 1 can be reduced by using polypropylene, which is a general-purpose plastic. In addition, the exhaust structure 1 can be made resistant to acids and alkalis and less likely to absorb water, and the exhaust structure 1 can be obtained which is less susceptible to condensed water or the like. Moreover, since polypropylene is hard to crack, the effect of preventing breakage of the synthetic resin exhaust structure 1 can be enhanced.

[Scope of invention disclosed in this specification]
In addition to each invention and embodiment listed as an invention, the invention disclosed in this specification is specified by changing these partial contents to other contents disclosed in this specification within the applicable range, Alternatively, what is specified by adding other contents disclosed in this specification to these contents, or what is specified by deleting these partial contents to the extent that partial effects can be obtained and making them a broader concept contain. The invention disclosed in this specification also includes the following modifications and additional contents.

For example, the configurations of the exhaust muffler, under panel, and diffuser in the exhaust structure of the present invention are not limited to the exhaust muffler 2, under panel 3, and diffuser 4 of the above-described embodiment, and are appropriate within the scope of the present invention. . Further, the exhaust structure of the present invention includes an appropriate structure in which the exhaust muffler and at least one kind of aero parts are integrally formed of the same synthetic resin such as heat-resistant resin. In addition, the under panel 3, the diffuser 4, or other aero parts are integrally formed from the same synthetic resin, or the exhaust muffler 2, the under panel 3, and the aero parts other than the diffuser 4 are synthesized from the same material. The present invention also includes one in which the exhaust muffler 2, the diffuser 4, and the aero parts other than the under panel 3 are integrally formed from the same synthetic resin.

In addition, the exhaust structure of the present invention is preferably formed in a flat shape that extends substantially horizontally as a whole from the viewpoint of improving aerodynamic characteristics. For example, the exhaust structure may have a shape in which a part of the exhaust muffler locally protrudes downward.

The present invention can be used as an exhaust structure for discharging exhaust from an internal combustion engine of an automobile.

DESCRIPTION OF SYMBOLS 1... Exhaust structure 2... Exhaust muffler 21... Flange 211... Insertion hole 22... Exhaust pipe 23... Sub-silencer 231... Internal partition 232... Through-hole group 24... Exhaust pipe 25...

Main silencer

251, 252, 253... Internal partition 254 Fastener 3 Under panel 31 Rectification ridge 32 Fastener 4

Diffuser

4a, 4b Diffuser part 41 Rectifier plate 42 Inclined plate 43 Horizontal plate 44 Fastener 100 Vehicle 101 Bottom 200 Cover Connection member 201 Flange 202 Insertion hole 301 Bolt 302 Nut 500 Existing exhaust muffler

Claims

An exhaust structure for mounting in an underfloor space of a vehicle, comprising:
An exhaust structure, wherein an exhaust muffler and at least one kind of aero parts are integrally formed of the same synthetic resin.
The exhaust muffler is formed in a flat shape extending substantially horizontally,
2. The exhaust structure according to claim 1, wherein the whole is formed in a flat shape extending substantially horizontally.
The exhaust muffler and the under panel as the aero parts are integrally formed of the same synthetic resin,
3. The exhaust structure according to claim 1, wherein the exhaust muffler is arranged below the under panel, is positioned substantially at the center of the under panel in the width direction, and extends forward and backward. .
The exhaust muffler and the diffuser, which is the aero part, are integrally formed of the same synthetic resin,
4. The exhaust structure according to any one of claims 1 to 3, wherein the exhaust muffler extends forward and backward between a pair of left and right diffuser portions forming the diffuser.
The exhaust muffler and the aero parts such as the under panel and the diffuser are integrally formed of the same synthetic resin,
The diffuser is continuously provided on the rear side of the under panel,
The exhaust muffler is arranged on the lower side of the under panel, is positioned substantially in the center of the width direction of the under panel, and extends forward and backward. extended to
5. The exhaust structure according to any one of claims 1 to 4, wherein the entire exhaust structure is formed in a flat shape extending substantially horizontally.
The exhaust structure according to any one of claims 1 to 5, wherein the synthetic resin is polypropylene.