JP6040128B2 - EGR device - Google Patents

Description

  The present invention relates to an EGR device mounted on a vehicle.

  For example, Patent Document 1 discloses an intake device that fixes a partition plate in an intake passage of an intake pipe in order to suppress intake noise when the throttle valve is opened.

  According to Patent Document 1, one end side of a plate-shaped valve body moves to the upstream side of the intake passage by rotation of the valve shaft of a throttle valve disposed in the intake passage of the internal combustion engine, and the other end side becomes the downstream side of the intake passage. As it moves, the high-velocity air flow that has passed through the gap formed between the one end side of the valve body and the inner wall surface of the intake passage mixes with the air flow downstream of the valve body to generate vortices, thereby Noise is supposed to be generated.

JP 2013-87730 A

  By the way, when the intake device disclosed in Patent Document 1 is applied to an exhaust gas recirculation (EGR) device (exhaust gas recirculation device) and an EGR introduction portion is arranged in the intake pipe, the EGR protruding into the intake passage is provided. It becomes difficult to arrange the partition plate by the introduction portion.

  Further, when the EGR introduction part is arranged in the intake pipe, a case where a sufficient length of the partition plate along the direction of air flow cannot be ensured is assumed.

  The present invention has been made in view of the above points, and an object thereof is to provide an EGR device capable of suppressing intake noise generated when a throttle valve is opened.

To achieve the above object, the present invention provides an intake passage forming member that forms an intake passage, an EGR introduction pipe that is connected to the intake passage formation member and introduces EGR gas into the intake passage, and the EGR A throttle valve disposed on the upstream side of the introduction pipe, and the EGR introduction pipe is bent toward the downstream in the direction of the intake flow, and a rising portion rising from the inner wall side of the intake passage into the intake passage. A rectifying member that rectifies intake air is provided outside the bent portion of the EGR introduction pipe, and the rectifying member is connected to the throttle valve on the outer wall of the bent portion. A partition plate is formed between the rectifying member and the throttle valve, and the rectifying member is arranged in the direction of the intake air flow. It is disposed at a position overlapping with the plate, characterized in Rukoto.

  According to the present invention, by being rectified (partitioned) by the rectifying member, mixing of intake air having different flow velocities is prevented, and generation of intake noise is minimized by minimizing the occurrence of vortices at the boundary portion. Can be suppressed.

Further , according to the present invention, since the protrusion is located on the side close to the throttle valve, intake air having different flow velocities can be rectified smoothly and efficiently.

Furthermore, according to the present invention, by arranging the rectifying member at a position overlapping the partition plate in the direction of the intake air flow, the intake air partitioned by the partition plate is further rectified, thereby further increasing the generation of intake noise. Can be suppressed.

  Furthermore, in the radial direction of the intake passage, the present invention may be configured such that a radial dimension from an inner wall surface on the main flow side of the intake air to a ridge line portion of the rectifying member is from the inner wall surface on the main flow side of the intake air. It is set larger than the radial dimension up to the upper surface of the partition plate, or the radial dimension from the inner wall surface on the main flow side of the intake air to the ridge line portion of the rectifying member is the inner dimension on the main flow side of the intake air. The radial dimension from the wall surface to the upper surface of the partition plate is set to be approximately the same.

  According to the present invention, by setting the radial dimensions from the inner wall surface on the mainstream side of the intake air to the ridge line portion of the rectifying member and the upper surface of the partition plate as described above, the partitioning action of the intake air by the partition plate and The intake air rectifying action by the rectifying member can be efficiently combined. By combining the partitioning action and the rectifying action, it is possible to further suppress the generation of intake noise.

  In the present invention, an EGR device capable of suppressing intake noise generated when the throttle valve is opened can be obtained.

1 is a schematic exploded perspective view of an engine to which an EGR device according to a reference embodiment of the present invention is applied. It is an expansion disassembled perspective view of the EGR block shown in FIG. It is a front view of the EGR gas introduction pipe seen from the throttle fastening flange side which is a mounting surface of the throttle valve. (A) is a front view of the rectifying member provided in the EGR gas introduction pipe, (b) is an enlarged longitudinal sectional view taken along line IV-IV of (a), (c) is a plan view of the rectifying member, (D) is a side view of a rectifying member. In a reference embodiment in which a rectifying member is provided in an EGR gas introduction pipe, it is an explanatory diagram showing a state in which intake air that has passed through a lower gap and an upper gap flows in an intake passage. In the comparative example in which the rectifying member is not provided, it is an explanatory view showing a state in which the intake air that has passed through the lower gap and the upper gap flows through the intake passage. It is a characteristic view which shows the relationship between the throttle opening and the sound pressure level of an intake flow in a reference embodiment and a comparative example. In an embodiment of the present invention , it is a front view of an EGR gas introduction pipe seen from the throttle fastening flange side which is an attachment surface of a throttle valve. FIG. 5 is an explanatory diagram showing a state in which intake air that has passed through a lower-side gap and an upper-side gap flows in an intake passage in the present embodiment in which a rectifying member and a partition plate are provided.

Next, reference embodiments of the present invention will be described in detail with reference to the drawings as appropriate. 1 is a schematic exploded perspective view of an engine to which an EGR device according to a reference embodiment of the present invention is applied, FIG. 2 is an enlarged exploded perspective view of an EGR block shown in FIG. 1, and FIG. 3 is a mounting surface of a throttle valve It is a front view of the EGR gas introduction pipe seen from the throttle fastening flange side. Note that “front and rear” and “up and down” indicated by arrows in each figure indicate the front and rear direction and the vertical direction of the vehicle body, and “left and right” indicate the left and right directions viewed from the driver's seat, respectively.

  As shown in FIG. 1, the engine 10 is an in-line four-cylinder engine mounted in an engine room of an automobile (not shown). The engine 10 includes a cylinder head 12 fastened to the upper surface of a cylinder block (not shown), a head cover 14 that covers the upper surface of the cylinder head 12, and the like.

  An intake flange 18 having four intake ports 16 and an EGR gas supply flange 22 having EGR gas supply holes 20 are provided on the front surface of the cylinder head 12. The intake port 16 communicates with a combustion chamber (not shown), and the EGR gas supply hole 20 communicates with an exhaust manifold (not shown) via an EGR gas introduction path and an EGR valve (not shown).

  An intake mechanism for introducing intake air into a combustion chamber (not shown) of the engine 10 is attached to the intake side of the cylinder head 12. The intake mechanism includes an intake manifold (intake passage forming member) 24 and an intake plate 26 interposed between the intake manifold 24 and the intake port 16.

  The intake manifold 24 includes an intake introduction pipe (intake pipe) 32 having a throttle fastening flange 30 to which a throttle valve 28 (see FIG. 5) is fastened, a surge chamber 34 connected to an upper portion of the intake introduction pipe 32, and a surge chamber. 34 and four branch pipes 36 connecting the intake plate 26 to each other. A single intake passage 38 through which intake air flows is formed inside the throttle valve 28 and the intake pipe 32.

  As shown in FIG. 5, the throttle valve 28 is fixed to the throttle shaft 40 through which the intake passage 38 having a substantially circular cross section passes, the valve shaft 42 provided so as to intersect the intake passage 38, and the valve shaft 42. The disc-shaped valve body 44 is provided. The valve shaft 42 is rotatably provided within a predetermined angle range by a rotational driving force of an electric actuator (not shown).

  As shown in FIG. 2, the intake air introduction pipe 32 has an EGR gas introduction flange 48 to which an EGR block 46 described later is fastened. The EGR gas introduction flange 48 is provided in the vicinity of the throttle fastening flange 30 (see FIG. 1). The EGR gas introduction flange 48 has a fitting hole 50 into which the EGR block 46 is fitted, a pair of bolts 52 (only one bolt 52 is shown and the other bolt 52 is not shown), and the periphery of the fitting hole 50. And a sealing member (not shown) for sealing the portion where the EGR gas introduction flange 48 and the EGR block 46 are fitted.

  The EGR device includes an EGR block 46 and an EGR valve (not shown). The EGR block 46 protrudes from the inner wall surface 32a of the intake air introduction pipe 32 and faces the intake passage 38, and is located on the downstream side of the throttle valve 28, and intake air (intake air) flowing through the intake passage 38 ).

  As shown in FIG. 1 or 2, the EGR block 46 is fastened to the EGR gas supply flange 22 via a pair of bolts 60 (however, only one bolt 60 is shown and the other bolt 60 is not shown). An engine-side flange 62 and a manifold-side flange 63 fastened to the EGR gas introduction flange 48 via a pair of bolts 52. An opening 64 communicating with the EGR gas supply hole 20 is formed in the engine side flange 62 (see FIG. 2). The EGR block 46 has an EGR gas introduction path 68 that communicates with an opening 64 formed in the engine side flange 62 and an opening 66 formed in the EGR gas introduction pipe 56.

  4A is a front view of the rectifying member provided in the EGR gas introduction pipe, FIG. 4B is an enlarged longitudinal sectional view taken along line IV-IV in FIG. 4A, and FIG. ) Is a plan view of the rectifying member, and FIG. 4D is a side view of the rectifying member.

  The EGR gas introduction pipe 56 is bent inside the EGR block 46 from the inner wall surface 32a side of the intake passage 38 to the intake passage 38, and to the downstream of the intake flow direction continuously from the rise portion 70a. And a bent portion 70b that opens later (see FIG. 4C). On the outer wall side (outer side) of the bent portion 70b of the EGR gas introduction pipe 56, a protruding portion that is a rectifying member 58 is integrally formed. The EGR block 46 and the rectifying member 58 are integrally formed of a metal material such as aluminum, for example.

In the reference embodiment, the rectifying member 58 is formed integrally with the EGR gas introduction pipe 56. However, the embodiment is not limited thereto, and the EGR gas introduction pipe 56 and the rectification member 58 are separately provided. The rectifying member 58 may be integrally joined to the outer wall of the bent portion 70b by a coupling means such as welding.

  The rectifying member 58 is formed by a protrusion located on the outer wall of the bent portion 70b closest to the throttle valve 28 (see FIG. 5 described later). Since the protruding portion which is the rectifying member 58 is located on the side closest to the throttle valve 28, intake air having different flow velocities can be rectified smoothly and efficiently.

  As shown in FIG. 4B, the rectifying member 58 has a top portion 72 which is located at the center in the longitudinal section and has the largest dimension in the height direction, and a skirt formed by bending from the top portion 72 equally to the left and right sides. Part 74. The ridgeline part 76 is formed by the top part 72 being continuous.

As shown in FIG. 4 (c), the ridge portion 76, continuous to the head 56a toward the opening 66 side has a EG R head 56a and dimensions substantially the same height direction of the gas inlet tube 56 And a ridge line portion 76 b continuous with the side portion 56 b of the EGR gas introduction pipe 56. Note that the ridge line portion 76a continuous to the head portion 56a and the ridge line portion 76b continuous to the side portion 56b are formed so as to intersect substantially obtusely (see FIG. 4C).

  Further, the projecting portion which is the rectifying member 58 is formed in a substantially rhombus shape in plan view as shown in FIG. 4 (a), and is formed in a mountain shape in front view as shown in FIG. 4 (c). Has been.

The engine 10 to which the EGR device according to the reference embodiment is applied is basically configured as described above. Next, the function and effect will be described.

  When the valve body 44 is gradually rotated by driving an electric actuator (not shown) from a state where the throttle valve 28 is closed and the valve body 44 closes the intake passage 38 (throttle opening 0 degree), one end of the valve body 44 is The side (lower side) is displaced upstream of the intake passage 38, and the other end side (upper side) of the valve body 44 is displaced downstream (see the state of FIG. 5).

  Due to the rotational displacement of the valve body 44, a lower gap 80 a formed between one end side of the valve body 44 and the inner wall surface 32 a of the intake passage 38, and the other end side of the valve body 44 and the inner wall of the intake passage 38. The intake air that has passed through the upper gap 80b formed there between flows in along the intake passage 38 (intake intake pipe 32). In this case, the flow velocity of the intake air (main flow) that has passed through the lower gap 80a is larger than the flow velocity of the intake air (wake) that has passed through the upper gap 80b, and is wide in the range from the outer peripheral portion of the intake passage 38 toward the center portion. Distributed.

  The intake air that has passed through the lower gap 80a and the upper gap 80b passes through an EGR gas introduction pipe 56 that is further arranged downstream of the throttle valve 28 and bulges toward the center of the intake passage 38.

  FIG. 5 is an explanatory diagram showing a state in which intake air that has passed through the lower gap and the upper gap flows in the intake passage in the present embodiment in which the EGR gas introduction pipe is provided with the rectifying member, and FIG. FIG. 6 is an explanatory diagram showing a state in which intake air that has passed through a lower gap and an upper gap flows in an intake passage in a comparative example in which no member is provided.

  As shown in FIG. 5, in this embodiment, the intake air (main flow) that has passed through the lower gap 80a and the intake air (wake) that has passed through the upper gap 80b are rectified (partitioned) by the rectifying member 58, respectively. Thus, mixing of the intake air that has passed through the lower gap 80a and the intake air that has passed through the upper gap 80b is prevented. As a result, collision between intake airs having different flow velocities can be avoided, and generation of intake noise can be suppressed by minimizing the occurrence of vortices at the boundary portion.

  On the other hand, as shown in FIG. 6, in the comparative example in which the EGR gas introduction pipe 56 is not provided with the rectifying member 58, a part of the intake air that has passed through the lower gap 80a and the intake air that has passed through the upper gap 80b. A portion of the EGR gas in the vicinity of the upstream side of the EGR gas introduction pipe 56, and intake noise is generated.

FIG. 7 is a characteristic diagram showing the relationship between the throttle opening and the sound pressure level of the intake air flow in the reference embodiment and the comparative example. In FIG. 7, the characteristic curve of the reference embodiment is indicated by a solid line, and the characteristic curve of the comparative example is indicated by a broken line. As can be understood from FIG. 7, as the flow rate of the intake air flowing through the intake passage 38 is increased by gradually increasing the throttle angle from 0 degree, the reference embodiment is compared with the predetermined throttle angle with respect to the comparative example. The sound pressure level is reduced and the generation of intake noise is suppressed.

As described above, in the reference embodiment, by providing the rectifying member (protrusion) 58 on the outer wall side of the bent portion 70b of the EGR gas introduction pipe 56, intake noise generated when the throttle valve 28 is opened can be suppressed. .

Next, it will be described in detail EGR apparatus according to the implementation embodiments of the present invention. The same components as those in the EGR device according to the reference embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

FIG. 8 is a front view of the EGR gas introduction pipe as viewed from the throttle fastening flange side which is a mounting surface of the throttle valve in the present embodiment, and FIG. 9 is a lower side in the present embodiment in which the rectifying member and the partition plate are provided. It is explanatory drawing which shows the state which the intake air which each passed the gap | interval and the upper side gap | circulation distribute | circulates in the intake passage.

In the EGR device according to the present embodiment, a partition plate 90 is newly disposed, and the throttle valve 28, the partition plate 90, and the rectifying member 58 are sequentially disposed along the direction of the intake air flow. This is different from the embodiment described above.

  The rectifying member 58 is disposed at a position overlapping the partition plate 90 in the direction of the intake air flow. By arranging the rectifying member 58 at a position overlapping with the partition plate 90 in the direction of the intake air flow, the intake air partitioned by the partition plate 90 is further rectified, thereby further suppressing the generation of intake noise. .

  The partition plate 90 is configured by combining a first partition plate 92 and a second partition plate 94 that are disposed substantially parallel to the intake flow direction and whose both ends are fixed to the inner wall of the intake passage 38. The first partition plate 92 has a trapezoidal vertical cross section orthogonal to the intake flow direction, and is formed to project in a convex shape toward the radially inner side of the intake passage 38. By surrounding the intake air that has passed through the lower gap 80a by the inner wall of the intake passage 38 and the first partition plate 92, the intake air that has passed through the lower gap 80a is prevented from mixing with the intake air that has passed through the upper gap 80b. (See FIG. 9). The second partition plate 94 has a flat plate shape, and the central portion of the flat second partition plate 94 is fixed to the central portion of the first partition plate 92.

  Next, the relationship between the partition plate 90 and the rectifying member 58 provided on the outer wall side of the bent portion 70b of the EGR gas introduction pipe 56 disposed on the downstream side of the partition plate 90 will be described.

  As shown in FIG. 8, when the throttle fastening flange 30 that is the mounting surface of the throttle valve 28 is viewed from the front, an imaginary line A passing through one side of the first partition plate 92 and an imaginary line B passing through the second partition plate 94. It is preferable that the ridge line portion 76 of the rectifying member 58 is set (positioned) within the range of the angle θ formed by. By setting the ridge portion 76 of the rectifying member 58 to be positioned within the range of the angle θ, the intake partitioning action by the partition plate 90 and the intake rectifying action by the rectifying member 58 can be efficiently combined. Because it can.

  Further, as shown in FIG. 9, the dimensional relationship in the radial direction is that the ridge portion of the rectifying member 58 extends from the inner wall surface 32a of the mainstream intake passage 38 passing through the lower gap 80a in the radial direction of the intake passage 38. When the dimension H1 in the radial direction up to 76 is set larger than the dimension H2 in the radial direction from the inner wall surface 32a of the intake channel 38 on the mainstream side passing through the lower gap 80a to the upper surface of the partition plate 90 (92). Good (H1> H2). Alternatively, in the radial direction of the intake passage 38, the radial dimension H1 from the inner wall surface 32a of the main-flow-side intake passage 38 that has passed through the lower-side gap 80a to the ridge line portion 76 of the rectifying member 58 passes through the lower-side gap 80a. The radial dimension H2 from the inner wall surface 32a of the intake channel 38 on the mainstream side to the upper surface of the partition plate 90 (92) may be set to be approximately the same (H1≈H2).

  The dimensions (H1, H2) in the radial direction from the inner wall surface 32a of the intake passage 38 on the mainstream side to the ridgeline portion 76 of the rectifying member 58 and the upper surface of the partition plate 90 are the above (H1> H2 or H1≈H2), respectively. By setting as described above, it is possible to efficiently combine the intake partitioning action by the partition plate 90 and the intake rectifying action by the rectifying member 58. By combining the partitioning action and the rectifying action, the generation of intake noise can be further suppressed.

24 Intake manifold (intake passage forming member)
28 Throttle valve 38 Intake passage 56 EGR gas introduction pipe (EGR introduction pipe)
58 Rectification member (protrusion)
66 Opening 70a Rising part 70b Bending part 76 Ridge line part 90 Partition plate 92 First partition plate 94 Second partition plate

Claims (2)

An intake passage forming member forming an intake passage;
An EGR introduction pipe connected to the intake passage forming member and introducing EGR gas into the intake passage;
A throttle valve disposed upstream of the EGR introduction pipe;
With
The EGR introduction pipe has a rising portion that rises into the intake passage from the inner wall side of the intake passage, and a bent portion that opens after bending toward the downstream in the direction of the intake flow,
A rectifying member that rectifies intake air is provided outside the bent portion of the EGR introduction pipe ,
The rectifying member is formed by a protrusion located on a side close to the throttle valve on the outer wall of the bent portion,
A partition plate is provided between the rectifying member and the throttle valve,
The rectifying member is disposed at a position overlapping the partition plate in the direction of the intake air flow EGR apparatus according to claim Rukoto. The EGR device according to claim 1 ,
In the radial direction of the intake passage, the radial dimension from the inner wall surface on the main flow side of the intake air to the ridge line portion of the rectifying member is the diameter from the inner wall surface on the main flow side of the intake air to the upper surface of the partition plate. Or the radial dimension from the inner wall surface on the main flow side of the intake air to the ridge line portion of the rectifying member is larger than the inner wall surface of the intake air on the upper surface of the partition plate. An EGR device characterized in that the EGR device is set substantially equal to the radial dimension up to.

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