JP7393202B2 - External gas distribution piping for internal combustion engines - Google Patents

Description

The present invention relates to external gas distribution piping for internal combustion engines.

Conventionally, as an example of an external gas distribution pipe for an internal combustion engine, an external gas distribution structure that distributes external gas to each cylinder of an internal combustion engine having a number of cylinders that is a multiple of 3 has been known (for example, see Patent Document 1). .

JP2016-89687A

In recent years, internal combustion engines have been required to reduce the number of cylinders due to demands for higher efficiency. Due to such demands, in recent years small displacement internal combustion engines have been used that have three cylinders, which is a multiple of three.

Furthermore, in recent years, there has been a demand for miniaturization of the overall structure of internal combustion engines. In order to downsize internal combustion engines, parts used in internal combustion engines, such as distribution pipes that distribute external gas for EGR (Exhaust Gas Recirculation), are also required to be downsized.

On the other hand, in the case of an internal combustion engine with two or more odd-numbered cylinders, such as a three-cylinder engine, when distributing external gas from one pipe connected to external gas to the intake pipe of each cylinder, the distribution ratio is The challenge is to make it nearly uniform.

However, in the external gas distribution structure of Patent Document 1, in order to improve the distribution ratio of external gas, one main pipe connected to external gas is branched into two upstream branch pipes and then collected into one pipe. It was collected in a pipe and then distributed to the intake pipes of each cylinder. For this reason, the external gas distribution structure of Patent Document 1 is particularly large in the reciprocating direction (vertical direction) of the piston, which is also the extending direction of the intake pipe, and further improvements have been sought in terms of miniaturization of the structure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an external gas distribution pipe for an internal combustion engine that can improve the distribution ratio of external gas to a plurality of intake pipes with a simple configuration. shall be.

In order to solve the above problems, an external gas distribution pipe for an internal combustion engine according to the present invention distributes external gas to a plurality of intake pipes each communicating with an odd number of cylinders in the internal combustion engine. one introduction part communicating with an external gas supply source; one external gas introduction pipe communicating with the introduction part through which the external gas can flow; a plurality of lead-out parts that lead out from the pipe to each of the intake pipes; a branch part that branches from the external gas introduction pipe into two of the lead-out parts; and a branch part that branches from the external gas introduction pipe to one of the lead-out parts. A distribution section.

In the external gas distribution pipe for an internal combustion engine according to one aspect of the present invention, the distribution part is provided in the external gas introduction pipe at a position closer to the introduction part than the branch part.

In the external gas distribution pipe for an internal combustion engine according to one aspect of the present invention, the pipe diameter of the branch part is larger than the pipe diameter of the distribution part.

In the external gas distribution pipe for an internal combustion engine according to one aspect of the present invention, the external gas introduction pipe is arranged with the longitudinal direction of the plurality of intake pipes being arranged.

In the external gas distribution pipe for an internal combustion engine according to one aspect of the present invention, a first branch forming a conduit from the branch part to one of the two lead-out parts that is farther from the introduction part. a second branch pipe forming a conduit from the branch part to the other of the two lead-out parts, and the length of the first branch pipe is equal to the length of the second branch pipe. Longer than the chief.

According to the present invention, it is possible to improve the distribution ratio of external gas to a plurality of intake pipes with a simple configuration.

1 is a plan view of an intake device including an external gas distribution pipe for an internal combustion engine according to an embodiment of the present invention. FIG. 1 is a perspective view of an intake device including an external gas distribution pipe for an internal combustion engine according to an embodiment. FIG. 1 is a front view of an intake device including an external gas distribution pipe for an internal combustion engine according to an embodiment. FIG. 2 is a plan view of an external gas distribution pipe of an internal combustion engine according to an embodiment. FIG. 3 is a bottom view of an external gas distribution pipe of an internal combustion engine according to an embodiment. FIG. 3 is a schematic diagram showing the flow of external gas in an intake device including an external gas distribution pipe according to an embodiment. FIG. 7 is a plan view of an external gas distribution pipe of an internal combustion engine according to a modification of the embodiment.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of an intake device 1 including an external gas distribution pipe 10 according to an embodiment of the present invention. FIG. 2 is a perspective view of the intake device 1 with the external gas distribution pipe 10. FIG. 3 is a front view of the intake device 1 including the external gas distribution pipe 10.

Hereinafter, for convenience of explanation, in the intake device 1 shown in FIGS. 1 to 3, the side where the external gas distribution pipe 10 is provided will be referred to as the front side, and the opposite side will be referred to as the rear side. In the following explanation, the longitudinal direction of the external gas distribution pipe 10 of an internal combustion engine is the x-axis direction (left-right direction, width direction), the short direction is the y-axis direction (front-rear direction), and the direction perpendicular to both the x-axis and the y-axis is The direction is the z-axis direction (vertical direction, height direction). In the following explanation, when explaining the positional relationship and direction of each component as right side, left side, front side, rear side, upper side, and lower side, it only refers to the positional relationship and direction in the drawing, and does not refer to the actual external gas of the internal combustion engine. This does not limit the positional relationship or direction in the distribution pipe.

As shown in FIGS. 1 to 3, in an intake system 1 included in an internal combustion engine (not shown), external gas is introduced into a plurality of intake pipes 21, 22, and 23 each communicating with an odd number of cylinders. One introduction part 11 which is an external gas distribution pipe 10 for distributing and communicated with an external gas supply source, and one external gas introduction pipe 12 which is communicated with the introduction part 11 and through which external gas can flow. A plurality of lead-out sections 13, 14, 15 that lead out external gas from the external gas introduction pipe 12 to each of the intake pipes 21, 22, 23, and two out of the lead-out parts 13, 14, 15 from the external gas introduction pipe 12. It includes a branching section 16 that branches into sections 13 and 14, and a distribution section 17 that distributes from the external gas introduction pipe 12 to one outlet section 15. The external gas distribution pipe 10 for an internal combustion engine according to the present embodiment will be specifically described below.

The intake device 1 includes the external gas distribution pipe 10 as described above. The intake device 1 is configured to be installed in, for example, an in-line three-cylinder engine (hereinafter referred to as an engine) as a gasoline engine (not shown). Note that three cylinders, which are an example of an odd number of plural cylinders included in an engine, are arranged along the x-axis in the order of the first cylinder, the second cylinder, and the third cylinder from the right side of the page in FIG. 1 to the left side (+x-axis direction). They are lined up in a row. Further, the intake device 1 constitutes a part of an intake system that supplies air to the engine. The intake device 1 includes an intake pipe 21 for the first cylinder, an intake pipe 22 for the second cylinder, an intake pipe 23 for the third cylinder, and an air cleaner (not shown) in which the intake pipes 21, 22, and 23 are assembled. The intake device main body 20 has a collecting pipe section 24 connected to the air intake device main body 20.

The intake device main body 20 includes an upper pipe section 25 that forms the upper front part of the intake pipes 21 , 22 , 23 , a lower front part of the intake pipes 21 , 22 , 23 , and a collecting pipe part 24 . It is composed of a lower pipe section 26, intake pipes 21, 22, 23, and a rear pipe section 27 that constitutes a rear portion of the collecting pipe section 24. The intake device main body 20 is formed by joining together an upper tube section 25, a lower tube section 26, and a rear tube section 27, all of which are made of resin, for example. The upper tube part 25 and the lower tube part 26 are joined by a joint part 28 provided near the vertical center of the intake device main body 20. Note that the component configuration of the intake device main body 20 is not limited to the example described above.

The intake pipe 21 has an opening 211 that communicates with the inside of the pipe as an opening for introducing external gas from the external gas distribution pipe 10 into the upper pipe section 25 . The intake pipe 22 has an opening 221 communicating with the inside of the pipe as an opening for introducing external gas from the external gas distribution pipe 10 into the upper pipe section 25. The intake pipe 23 has an opening 231 that communicates with the inside of the pipe as an opening for introducing external gas from the external gas distribution pipe 10 into the upper pipe section 25 .

As shown in FIGS. 1 to 3, the external gas distribution pipe 10 is attached to the upper front side of the intake device main body 20 in the intake device 1. As shown in FIGS. In the external gas distribution pipe 10, the outlet part 13 is connected to the opening 211 of the intake pipe 21, the outlet part 14 is connected to the opening 221 of the intake pipe 22, and the outlet part 15 is connected to the opening 231 of the intake pipe 23. There is.

FIG. 4 is a plan view of the external gas distribution pipe 10. Moreover, FIG. 5 is a bottom view of the external gas distribution pipe 10.

As shown in FIGS. 4 and 5, the external gas distribution pipe 10 includes the introduction part 11, the external gas introduction pipe 12, the delivery parts 13, 14, 15, the branch part 16, and the distribution part 17, as described above. We are prepared. The external gas distribution pipe 10 is formed by joining an upper part 18 constituting an upper part and a lower part 19 constituting a lower part, both of which are made of resin, for example.

The introduction section 11 is communicated with the external gas supply source (not shown) in order to introduce external gas from the external gas supply source into the external gas distribution pipe 10 .

The external gas introduction pipe 12 is a single pipe line that communicates the introduction section 11 with the plurality of outlet sections 13, 14, and 15. The external gas introduction pipe 12 is arranged such that the longitudinal direction thereof is the direction in which the plurality of intake pipes 21, 22, and 23 are arranged, that is, the left-right direction (x-axis direction). The external gas introduction pipe 12 is formed into a straight pipe shape or a substantially straight pipe shape. By being formed in this way, the external gas introduction pipe 12 can cause the external gas introduced from the external gas supply source to flow through the intake pipes 21 , 22 , 23 of the intake device main body 20 .

Three derivation parts 13, 14, and 15 are provided depending on the number of cylinders of the engine. As described above, the lead-out part 13 is connected to the opening 211 of the intake pipe 21, the lead-out part 14 is connected to the opening 221 of the intake pipe 22, and the lead-out part 15 is connected to the opening 231 of the intake pipe 23. Since the outlet parts 13, 14, and 15 communicate with the introduction part 11 via the external gas introduction pipe 12, external gas can be led out from the external gas introduction pipe 12 to the intake pipes 21, 22, and 23, respectively. I can do it.

The branch part 16 is located at the farthest position from the introduction part 11 in the external gas introduction pipe 12, specifically, at the other end 122 on the opposite side (+x-axis direction side) from the one end 121 where the introduction part 11 is provided. It is set in. The branching part 16 is connected to two of the lead-out parts 13, 14, and 15 from the external gas introduction pipe 12 after the pipe line is bent from the other end 122 of the external gas introduction pipe 12 to the rear side (+y-axis direction side). , a lead-out part 13 connected to the intake pipe 21 of the first cylinder, and a lead-out part 14 connected to the intake pipe 22 of the second cylinder. That is, the branch part 16 is a so-called tournament piping in which one pipe (external gas introduction pipe 12) branches off and is connected to two pipes (first branch pipe 131 and second branch pipe 141).

The first branch pipe 131 connects the two outlet parts 13 and 14 branched from the branch part 16 to the one outlet part 13 that is farther from the introduction part 11 (distance in the x-axis direction or pipe length). is forming. The second branch pipe 141 is one of the two lead-out parts 13 and 14 branched from the branch part 16, which is shorter in distance from the introduction part 11 (distance in the x-axis direction or pipe length) than the lead-out part 13. 14. Here, the pipe length L1 of the first branch pipe 131 is longer than the pipe length L2 of the second branch pipe.

The first branch pipe 131 is provided with a bending part 132 between the branch part 16 and the lead-out part 13 for bending the pipe in a predetermined direction, for example, the +y-axis direction. Further, the second branch pipe 141 is provided with a bending part 142 between the branch part 16 and the lead-out part 14 for bending the pipe line in a predetermined direction, for example, in the +y-axis direction. Here, the curvature of the bent portion 132 is larger (the degree of bending is tighter) than that of the bent portion 142.

The distribution part 17 is provided in the external gas introduction pipe 12 at a position closer to the introduction part 11 than the branch part 16 (closer to the -x axis direction). In the distribution part 17, a pipe line (distribution pipe 151) is distributed directly from the external gas introduction pipe 12 to the derivation part 15. The pipe diameter of the distribution part 17 is larger than the pipe diameter of the branch part 16. The distribution section 17 distributes external gas from one external gas introduction pipe 12 to one outgoing section 15 among the plurality of outgoing sections 13 , 14 , and 15 .

Next, the operation of the external gas distribution pipe 10 described above will be explained.

FIG. 6 is a schematic diagram showing the flow of external gas in the intake device 1 including the external gas distribution pipe 10 according to the embodiment.

As shown in FIG. 6 , in the intake device 1 including the external gas distribution pipe 10 , external gas is introduced into the external gas distribution pipe 10 from the introduction part 11 . The external gas introduced into the external gas distribution pipe 10 passes through the external gas introduction pipe 12 and is sent to the intake pipe 21 from the derivation parts 13, 14, 15 provided corresponding to a plurality of cylinders of the engine. , 22, 23.

Here, the external gas distribution pipe 10 includes a branch part 16 that branches from the external gas introduction pipe 12 into two lead-out parts 13 and 14, and a distribution part 17 that distributes to one lead-out part 15. In particular, in the external gas distribution pipe 10 , the distribution section 17 is provided at a position closer to the introduction section 11 than the branch section 16 in the external gas introduction pipe 12 .

With this configuration, the external gas distribution pipe 10 communicates with the two outlet parts 13 and 14 rather than the external gas G3 distributed to the distribution part 17 which communicates with one outlet part 13. The difference in distribution ratio between the external gases G1 and G2 distributed to the branch portion 16 can be improved.

Further, in the external gas distribution pipe 10, the pipe diameter of the branch part 16 is formed to be larger than the pipe diameter of the distribution part 17. Therefore, the external gas distribution pipe 10 can improve the difference in the distribution ratio between the external gases G1 and G2 distributed to the branch part 16 communicating with the two outlet parts 13 and 14.

In addition, in the external gas distribution pipe 10, the external gas introduction pipe 12 is arranged with the longitudinal direction of the plurality of intake pipes 21, 22, 23 (lateral direction, x-axis direction) as the longitudinal direction. It is possible to prevent the piston from increasing in the reciprocating direction (vertical direction), which is also the direction of extension of the pistons 22 and 23, and to improve the miniaturization of the structure.

The external gas distribution pipe 10 also includes a first branch pipe 131 that forms a pipe line from the branch part 16 to one outlet part 13 that is far from the introduction part 11, and a first branch pipe 131 that forms a pipe line from the branch part 16 to the other outlet part 14. A second branch pipe 141 is provided. Here, the length of the first branch pipe 131 is longer than the length of the second branch pipe 141. With this configuration, the external gas distribution pipe 10 improves the distribution ratio to the outlet section 13, which is located far from the introduction section 11, where the distribution ratio of external gas tends to be high, and provides a simple structure. Depending on the configuration, the distribution ratio of external gas can be further improved.

As described above, according to the external gas distribution pipe 10 for an internal combustion engine according to the embodiment, it is possible to improve the external gas distribution ratio with a simple configuration in an odd-numbered multi-cylinder engine such as three cylinders. can.

Although the embodiments of the present invention have been described above, the present invention is not limited to the external gas distribution pipes 10 and 10A of the internal combustion engine according to the above embodiments, and is not limited to the concept of the present invention and the scope of the claims. including all aspects contained therein. Moreover, each structure may be selectively combined as appropriate so as to achieve at least some of the problems and effects described above. For example, the shape, material, arrangement, size, etc. of each component in the above embodiments may be changed as appropriate depending on the specific usage mode of the present invention.

FIG. 7 is a plan view of an external gas distribution pipe 10A of an internal combustion engine according to a modification of the embodiment. As shown in FIG. 7, in the modified example of the external gas distribution pipe 10A, unlike the external gas distribution pipe 10 described above, the introduction part 11A is provided on the left side in the left-right direction (closer to the +x-axis direction), and the branch part 16A is provided on the right side in the left-right direction (closer to the -x axis direction). In this way, the external gas distribution pipe 10A has a configuration and arrangement other than the arrangement of the branch part 16A and the distribution part 17A with respect to the introduction part 11A and the external gas introduction pipe 12, and the difference in pipe diameter between the branch part 16 and the distribution part 17. can be changed as appropriate.

1... Intake device, 10, 10A... External gas distribution pipe, 11, 11A... Introducing part, 12... External gas introduction pipe, 12, 12A... External gas introduction pipe, 13, 13A, 14, 14A, 15, 15A... Outlet Part, 16, 16A... Branch part, 17, 17A... Distribution part, 18... Upper part, 19... Lower part, 20... Intake device main body, 21, 22, 23... Intake pipe, 24... Collecting pipe part, 25... Upper pipe part 25... Upper pipe part, 26... Lower pipe part, 27... Rear side pipe part, 28... Joint part, 121... One end part, 122... Other end part, 131... First branch pipe, 141... Second Branch pipe, 151...Distribution pipe

Claims (3)

An external gas distribution pipe that distributes external gas to a plurality of intake pipes each communicating with an odd number of cylinders in an internal combustion engine,
one inlet in communication with an external gas supply source;
one external gas introduction pipe that is in communication with the introduction part and through which the external gas can flow;
a plurality of lead-out portions that lead out the external gas from the external gas introduction pipe to each of the intake pipes;
a branch part that branches from the external gas introduction pipe into two of the outlet parts;
a distribution part that distributes from the external gas introduction pipe to one of the outlet parts, is provided at a position closer to the introduction part than the branch part, and extends in a direction opposite to the branch part;
Equipped with
The branch portion extends linearly approximately parallel to the external gas introduction pipe, and
a first branch pipe forming a conduit from the branch part to one of the two lead-out parts that is farther from the introduction part;
a second branch pipe forming a conduit from the branch part to the other of the two lead-out parts;
Equipped with
The length of the first branch pipe is longer than the length of the second branch pipe,
The first branch pipe is provided with a first bending part that bends the pipe in a predetermined direction between the branch part and one of the lead-out parts,
The second branch pipe is provided with a second bending part that bends the pipe in a predetermined direction between the branch part and the other lead-out part,
An external gas distribution pipe for an internal combustion engine , wherein the first bend has a larger curvature than the second bend . The pipe diameter of the branch part is larger than the pipe diameter of the distribution part,
An external gas distribution pipe for an internal combustion engine according to claim 1 . The external gas introduction pipe is arranged with the direction in which the plurality of intake pipes are arranged as a longitudinal direction.
An external gas distribution pipe for an internal combustion engine according to claim 1 or 2 .

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