JP6133771B2 - Gas mixing equipment - Google Patents

Description

  The present invention relates to a gas mixing device that mixes exhaust gas flowing in an EGR (Exhaust Gas Recirculation) passage with fresh air flowing in an intake passage.

  The EGR diffusion unit of Patent Literature 1 is used when exhaust gas is mixed with fresh air gas in an intake / exhaust system. The EGR diffusion unit includes an intake passage and an outer peripheral passage. The intake passage is disposed on the radially inner side of the outer peripheral passage. The intake passage and the outer peripheral passage are partitioned by a partition wall. A plurality of EGR outlets are arranged in the partition wall. Exhaust gas is introduced into the outer peripheral passage from the high pressure EGR passage. The introduced exhaust gas flows into the intake passage through a plurality of EGR outlets. The exhaust gas is mixed with fresh air gas flowing through the intake passage.

JP 2011-64163 A

  However, the EGR diffusion unit is arranged independently from the high pressure EGR regulating valve of the high pressure EGR flow path. For this reason, there are many apparatuses which comprise an intake / exhaust system. That is, the structure of the intake / exhaust system is complicated.

  Further, out of the fresh air gas flowing through the intake passage, the fresh air gas in the radially outer portion is mixed with the exhaust gas introduced from the EGR outlet relatively easily. However, among the fresh air gas flowing through the intake passage, the fresh air gas in the central portion in the radial direction is difficult to be mixed with the exhaust gas introduced from the EGR outlet. That is, the exhaust gas is introduced into the intake passage from the partition wall, that is, the EGR outlet opened on the inner peripheral surface of the intake passage. For this reason, the exhaust gas hardly reaches the fresh air gas in the central portion in the radial direction.

  Further, the exhaust gas is introduced into the intake passage from a plurality of EGR outlets. Here, among the plurality of EGR outlets, from the EGR outlet disposed on the axis of the high pressure EGR passage, the exhaust gas having a relatively high flow rate can be introduced into the intake passage. If the exhaust gas has a high flow velocity, it is easy to reach the fresh air gas in the central portion in the radial direction of the intake passage.

  However, the flow resistances of the plurality of EGR outlets are set so as to increase as they approach the high-pressure EGR passage. That is, among the plurality of EGR outlets, the EGR outlet disposed on the axis of the high-pressure EGR passage has the largest flow path resistance. For this reason, it is difficult to introduce exhaust gas having a high flow velocity into the intake passage.

  Accordingly, an object of the present invention is to provide a gas mixing device that can simplify the configuration of an intake / exhaust system and that allows exhaust gas to easily reach fresh air near the radial center portion of the intake passage. To do.

  (1) In order to solve the above problems, the gas mixing device of the present invention has an intake passage through which fresh gas flows, and an EGR passage that introduces exhaust gas into the intake passage and has a junction at the downstream end. A housing in which a poppet valve capable of adjusting the flow rate of the exhaust gas is disposed, a valve shaft insertion hole that is disposed between the junction and the intake passage, and through which the valve shaft of the poppet valve is inserted, A partition wall having an introduction hole that opens to the intake passage, and the intake passage and the EGR passage extend in a direction crossing each other, as viewed from the passage length direction of the EGR passage. The valve shaft insertion hole and the introduction hole are arranged on the radially inner side of the junction port.

  Here, the “fresh air gas” refers to a gas before the exhaust gas merges from the gas mixing apparatus of the present invention. For example, when there is another gas mixing device on the upstream side of the gas mixing device of the present invention, and the exhaust gas is already mixed with the fresh air gas from the gas mixing device, the fresh gas mixed with the exhaust gas is It corresponds to fresh air gas in the gas mixing apparatus of the present invention.

  The gas mixing device of the present invention and the EGR valve assembly for adjusting the flow rate of the exhaust gas share a housing. That is, the gas mixing device of the present invention and the EGR valve assembly are integrated through the housing. For this reason, compared with the case where a gas mixing apparatus and an EGR valve assembly are separate bodies, the number of apparatuses constituting the intake / exhaust system is reduced. Therefore, the structure of the intake / exhaust system can be simplified.

  In addition, according to the gas mixing device of the present invention, the introduction hole is arranged on the radially inner side of the merge port as seen from the passage length direction of the EGR passage. In other words, as viewed from the intake passage, the introduction hole and the junction are arranged in series. For this reason, the exhaust gas flowing into the intake passage through the introduction hole is unlikely to stall. Therefore, the exhaust gas easily reaches the fresh air gas in the vicinity of the central portion in the radial direction of the intake passage. Therefore, exhaust gas and fresh air gas can be sufficiently mixed.

  Further, according to the gas mixing device of the present invention, exhaust gas having a high flow velocity that flows along the valve shaft of the poppet valve can be introduced into the intake passage from the introduction hole. For this reason, exhaust gas and fresh air gas can be sufficiently mixed.

  Further, the exhaust gas has a higher temperature than the fresh gas. For this reason, temperature unevenness is likely to occur in the fresh gas mixed with the exhaust gas. In particular, a large temperature difference is likely to occur between the fresh gas (high temperature) in the radially outer portion of the intake passage and the fresh gas (low temperature) near the radial center portion of the intake passage. In this regard, according to the gas mixing device of the present invention, the exhaust gas easily reaches the fresh air gas in the vicinity of the central portion in the radial direction of the intake passage. Therefore, temperature unevenness is less likely to occur in fresh air mixed with exhaust gas.

  (1-1) In the configuration of (1), it is preferable that the intake passage and the EGR passage extend in directions orthogonal to each other. According to this configuration, the extending direction of the EGR passage is directed to the radial center of the intake passage. For this reason, the exhaust gas easily reaches the fresh air gas in the vicinity of the central portion in the radial direction of the intake passage. Therefore, exhaust gas and fresh air gas can be sufficiently mixed.

  (2) In the configuration of the above (1), the partition wall portion has a plurality of flow dividing holes that open to the intake passage, and the plurality of flow dividing holes, when viewed from the passage length direction of the EGR passage, It is better to have a configuration arranged on the radially outer side of the mouth.

  According to this configuration, the exhaust gas is introduced from the EGR passage into the intake passage through the introduction hole and the plurality of branch holes. Here, when viewed from the passage length direction of the EGR passage, the plurality of diversion holes are arranged on the radially outer side of the merge port. For this reason, compared with the exhaust gas introduced into the intake passage through the introduction hole, the exhaust gas introduced into the intake passage through the diversion hole has a slower flow velocity. Therefore, according to this configuration, the high-speed exhaust gas via the introduction hole can be mixed with the fresh air gas near the radial center portion of the intake passage. In addition, the low-speed exhaust gas via the diversion holes can be mixed with the fresh air gas in the radially outer portion of the intake passage. Therefore, exhaust gas and fresh air gas can be sufficiently mixed.

  In addition, according to this configuration, the exhaust gas can be divided into small blocks and introduced into the intake passage as compared with the case of a single flow dividing hole. For this reason, the heat transfer area of the exhaust gas with respect to fresh air gas becomes large. Therefore, temperature unevenness is less likely to occur in fresh air mixed with exhaust gas.

  (2-1) In the configuration of (2), it is preferable that the upstream side of the intake passage has a larger opening area of the diversion hole with respect to the intake passage than the downstream side. Here, the “opening area” means the sum of the opening areas of the plurality of flow dividing holes with respect to the intake passage when a plurality of flow dividing holes are arranged on the upstream side or the downstream side.

  In the intake passage, the exhaust gas introduced from the upstream diversion hole has a longer contact time with the fresh air gas than the exhaust gas introduced from the downstream diversion hole. For this reason, the exhaust gas introduced from the upstream diversion hole is more easily mixed with the fresh air gas than the exhaust gas introduced from the downstream diversion hole.

  In this regard, according to the present configuration, the amount of exhaust gas introduced is larger in the upstream flow dividing holes than in the downstream flow dividing holes. For this reason, the larger the amount of exhaust gas introduced, the longer the contact time with the fresh air gas. Therefore, exhaust gas and fresh air gas can be sufficiently mixed. Further, temperature unevenness is less likely to occur in fresh air mixed with exhaust gas.

  (3) In the configuration of the above (1) or (2), the housing has a housing chamber in which the intake passage and the partition wall are housed radially inside, and the EGR passage is in the housing chamber. It is better to be connected from the outside in the radial direction. According to this configuration, the partition wall is housed in the housing chamber, that is, the housing. For this reason, a partition part can be protected from the impact from the outside.

  (4) In any one of the constitutions (1) to (3), the partition wall is separate from the housing, and the valve shaft insertion hole and the introduction hole are formed in the partition wall. It is better to have a configuration. According to this configuration, the valve shaft insertion hole and the introduction hole can be easily arranged in the partition wall.

  ADVANTAGE OF THE INVENTION According to this invention, the structure of an intake / exhaust system can be simplified and the gas mixing apparatus with which exhaust gas can reach | attain fresh air gas near the radial direction center part of an intake passage can be provided.

It is a schematic diagram of the intake / exhaust system in which the gas mixing apparatus which is one Embodiment of this invention is arrange | positioned. It is a perspective sectional view of the gas mixing device. FIG. 3 is a sectional view in the intake passage direction in the vicinity of a partition wall in FIG. 2. FIG. 3 is a sectional view in the valve axis direction in the vicinity of a partition wall in FIG. 2. It is a permeation | transmission figure of the partition part vicinity of FIG. FIG. 6 is an exploded view of the housing and the partition wall in FIG. 5. It is a development view of the inner peripheral surface of the partition wall in the circumferential direction.

  Hereinafter, embodiments of the gas mixing apparatus of the present invention will be described.

<Configuration of intake / exhaust system>
First, the structure of the intake / exhaust system in which the gas mixing apparatus of the present embodiment is arranged will be described. In FIG. 1, the schematic diagram of the intake / exhaust system by which the gas mixing apparatus of this embodiment is arrange | positioned is shown. As shown in FIG. 1, the intake / exhaust system 9 includes an intake system 90, an exhaust system 91, an HPL (High Pressure Loop) -EGR system 92, and an LPL (Low Pressure Loop) -EGR system 93. Yes.

  The intake system 90 includes an intake-side turbo bypass valve 900, an intercooler switching valve 901, an intercooler 902, and a throttle valve 903. The intake system 90 supplies fresh air gas G3 to the engine 94.

  The exhaust system 91 includes an exhaust side turbo bypass valve 910, an exhaust brake valve 911, a DPF (Diesel Particulate Filter) 912, and an exhaust throttle valve 913. The exhaust system 91 discharges the exhaust gas G2 from the engine 94. A first turbocharger 95 and a second turbocharger 96 are arranged between the intake system 90 and the exhaust system 91.

  The HPL-EGR system 92 is disposed between the exhaust side of the engine 94 and the intake system 90 (specifically, the downstream side of the throttle valve 903). The HPL-EGR system 92 includes an EGR cooler switching valve 920, an HPL-EGR valve 921, and an EGR cooler 922. The HPL-EGR system 92 returns a part of the exhaust gas G2 to the intake system 90.

  The LPL-EGR system 93 is disposed between the exhaust system 91 (specifically, downstream of the DPF 912) and the intake system 90 (specifically, upstream of the second turbocharger 96). The LPL-EGR system 93 includes an LPL-EGR valve 931 and an EGR cooler 932. The LPL-EGR system 93 returns a part of the exhaust gas G2 to the intake system 90.

  Among the plurality of valves in the intake / exhaust system 9, the gas mixing device of the present embodiment is disposed near the LPL-EGR valve 931.

<Configuration of gas mixing device>
Next, the structure of the gas mixing apparatus of this embodiment is demonstrated. FIG. 2 shows a perspective cross-sectional view of the gas mixing apparatus of the present embodiment. FIG. 3 shows a sectional view in the intake passage direction in the vicinity of the partition wall in FIG. FIG. 4 shows a sectional view in the valve shaft direction in the vicinity of the partition wall in FIG. FIG. 5 shows a transmission diagram near the partition wall in FIG. FIG. 6 is an exploded view of the housing and the partition wall shown in FIG. FIG. 7 shows a development in the circumferential direction of the inner peripheral surface of the partition wall.

  As shown in FIGS. 2 to 7, the gas mixing device 1 of the present embodiment includes a housing 2, a partition wall 3, and intake pipes 70 and 71. The housing 2 is shared with a housing of an EGR valve assembly 8 (corresponding to the LPL-EGR valve 931 shown in FIG. 1) described later.

[Housing 2]
The housing 2 includes a storage chamber 20, an EGR passage 21, and a spring storage chamber 22. The storage chamber 20 extends in the front-rear direction. The radial cross section of the storage chamber 20 has a perfect circle shape. A step 20 a is formed at the rear end of the storage chamber 20. As shown in FIG. 4, a convex portion 20 b that protrudes radially inward is formed on the upper portion of the inner peripheral surface of the storage chamber 20. Further, a boss portion 20 c is projected from the upper portion of the inner peripheral surface of the rear portion of the storage chamber 20. A valve shaft 800 of a poppet valve 80 of an EGR valve assembly 8 to be described later is inserted into the boss portion 20c in the radial direction so as to be movable in the vertical direction.

  An intake passage 202 is disposed inside the storage chamber 20. The intake passage 202 extends in the front-rear direction. The radial cross section of the intake passage 202 has a perfect circle shape. The intake passage 202 is disposed on the radially inner side of the partition wall 3 described later. A fresh gas inlet 200 is disposed at the front end (one axial end, upstream end) of the intake passage 202. A fresh air gas G1 flows into the fresh air inlet 200 from an intake pipe 70 described later. On the other hand, a fresh gas outlet 201 is disposed at the rear end (the other end in the axial direction, the downstream end) of the intake passage 202. From the fresh air outlet 201, fresh gas (mixed gas of fresh gas G1 and exhaust gas G2) G3 mixed with the exhaust gas G2 flows out.

  The EGR passage 21 extends in the vertical direction. The radial cross section of the EGR passage 21 has a perfect circle shape. The EGR passage 21 is branched downward from the storage chamber 20. An exhaust gas inlet 210 is disposed at the lower end (one axial end, upstream end) of the EGR passage 21. The exhaust gas inlet 210 is connected to the downstream side of the EGR cooler 932 of the LPL-EGR system 93 shown in FIG. The exhaust gas G2 flows into the exhaust gas inlet 210. On the other hand, a confluence 211 is disposed at the upper end (the other end in the axial direction, the downstream end) of the EGR passage 21. As shown in FIGS. 3 and 5, the junction port 211 opens into the storage chamber 20 from the lower side (outside in the radial direction). The spring accommodating chamber 22 is disposed on the upper side of the accommodating chamber 20. As shown in FIG. 2, the spring accommodating chamber 22 accommodates a spring 82 of the EGR valve assembly 8 described later.

[Intake pipes 70, 71]
As shown in FIGS. 2, 3, and 5, the intake pipe 70 is disposed on the front side of the housing 2. The intake pipe 70 is connected to the downstream side of the intake port 930 of the intake system 90 shown in FIG. An intake passage 700 is formed inside the intake pipe 70. The intake passage 700 extends in the front-rear direction. A cross section in the radial direction of the intake passage 700 has a perfect circle shape. The intake passage 700 communicates with the fresh air inlet 200.

  As shown in FIGS. 2, 3, and 5, the intake pipe 71 is disposed on the rear side of the housing 2. The intake pipe 71 is connected to the upstream side of the second turbocharger 96 of the intake system 90 shown in FIG. An intake passage 710 is formed in the intake pipe 71. The intake passage 710 extends in the front-rear direction. The radial cross section of the intake passage 710 has a perfect circle shape. The intake passage 710 communicates with the fresh air gas outlet 201.

[Partition 3]
As shown in FIGS. 2 to 6, the partition wall 3 is made of metal and has a cylindrical shape. The partition wall 3 is disposed inside the storage chamber 20. The partition wall 3 covers the junction 211 from above. The partition wall 3 partitions the junction port 211 and the intake passage 202. The rear end of the partition 3 is in contact with the step 20a. By the contact, the front-rear direction position of the partition wall 3 with respect to the storage chamber 20 is determined. As shown in FIG. 4, a convex portion 3 b that projects outward in the radial direction is formed on the upper portion of the outer peripheral surface of the partition wall portion 3. The convex portion 3 b is in contact with the convex portion 20 b of the housing 2. Due to the contact, the radial position of the partition wall 3 with respect to the storage chamber 20 is determined. As shown in FIG. 7, a semicircular cutout 3a is provided in the convex portion 3b. The notch 3a is in contact with the first half of the outer peripheral surface of the boss 20c.

  As shown in FIG. 7, the partition wall portion 3 is provided with a total of ten flow dividing holes 30d, a total of six flow dividing holes 30e, a total of three introduction holes 32, and a valve shaft insertion hole 31. Has been. The diversion holes 30d and 30e and the introduction hole 32 communicate with the EGR passage 21 and the intake passage 202, respectively. The diversion holes 30d and 30e and the introduction hole 32 will be described in detail later. A valve shaft 800 of a poppet valve 80 of the EGR valve assembly 8 described later is inserted into the valve shaft insertion hole 31 so as to be movable in the vertical direction.

<Configuration of EGR valve assembly>
Next, the configuration of the EGR valve assembly that shares the housing with the gas mixing apparatus of the present embodiment will be briefly described. As shown in FIG. 2, the EGR valve assembly 8 includes a housing 2 shared with the gas mixing device 1, a poppet valve 80, a valve seat 81, a spring 82, and a motor 83.

  The valve seat 81 is disposed below the junction 211 of the EGR passage 21. The poppet valve 80 includes a valve shaft 800 and a valve body 801. The valve body 801 can be seated and separated from the valve seat 81 from below. The valve shaft 800 protrudes upward from the upper surface of the valve body 801. The valve shaft 800 extends in the vertical direction. The valve shaft 800 extends from the spring accommodating chamber 22 to the EGR passage 21 across the accommodating chamber 20 in the radial direction. A flange portion 800 a is disposed at the upper end of the valve shaft 800. The spring 82 is interposed between the bottom surface of the spring accommodating chamber 22 of the housing 2 and the flange portion 800 a of the valve shaft 800. The spring 82 biases the valve shaft 800, that is, the poppet valve 80 upward. The motor 83 covers the spring accommodating chamber 22 from above. The motor 83 includes a gear (not shown) and a motor side shaft 830. The motor 83 rotationally drives the gear. The gear reciprocates the motor side shaft 830 in the vertical direction. The lower end of the motor side shaft 830 is in contact with the upper end of the valve shaft 800.

  When the valve closing state is switched to the valve opening state shown in FIG. 2, the motor 83 is driven to lower the valve shaft 800 against the urging force of the spring 82. The valve body 801 is separated from the valve seat 81. On the other hand, when switching from the valve open state shown in FIG. 2 to the valve closed state, the motor 83 is stopped and the valve shaft 800 is raised by the urging force of the spring 82. The valve body 801 is seated on the valve seat 81.

<About diversion holes and introduction holes>
Next, the flow dividing holes 30d and 30e and the introduction hole 32 of the gas mixing apparatus of this embodiment will be described. As shown in FIG. 4, as viewed from the front side, a vertical straight line passing through the radial center of the storage chamber 20 (the radial center of the intake passage 202 and the radial center of the partition wall 3) A 1, that is, the radial direction of the confluence 211. The flow dividing holes 30d and 30e are arranged symmetrically with respect to the center L1.

  As shown in FIG. 7, in the developed view of the inner peripheral surface of the partition wall portion 3, the flow dividing holes 30 d and 30 e are arranged symmetrically with respect to the radial center A <b> 1 of the storage chamber 20. That is, when the angle advances in the clockwise direction when viewed from the front side with the lower end of the partition wall 3 at the 0 ° position, the configuration from the 0 ° position to the 180 ° position when passing through the 90 ° position (clockwise) The configuration from the 0 ° position to the 180 ° position (counterclockwise) when passing through the 270 ° position is bilaterally symmetric.

  As shown in FIG. 7, the radial cross section of the flow dividing hole 30d has a perfect circle shape. The ten branch holes 30d are arranged in the circumferential direction and the front-rear direction. The cross section in the radial direction of the flow dividing hole 30e has a perfect circle shape. The flow dividing hole 30e has a smaller diameter than the flow dividing hole 30d. The six branch holes 30d are arranged in the circumferential direction and the front-rear direction.

  As shown in FIG. 4, the introduction holes 32 are arranged symmetrically with respect to the vertical straight line passing through the radial center A <b> 1 of the storage chamber 20, that is, the radial center L <b> 1 of the merge port 211 as viewed from the front side. Yes. As shown in FIGS. 4 and 7, the three introduction holes 32 are arranged on the inner side in the radial direction of the junction port 211 when viewed from the upper side (the inner side in the radial direction of the intake passage 202).

<Motion of gas mixing device>
Next, the movement of the gas mixing device of this embodiment will be described. In the valve open state shown in FIG. 2, the valve body 801 of the poppet valve 80 is separated from the valve seat 81. For this reason, the exhaust gas G2 is introduced from the EGR passage 21 into the intake passage 202 through the gap between the valve body 801 and the valve seat 81.

  Specifically, as shown in FIGS. 4 and 7, the exhaust gas G <b> 2 is introduced from the exhaust gas inlet 210 through the EGR passage 21, the merging port 211, the diversion holes 30 d and 30 e, and the introduction hole 32. It flows into 202. At this time, the exhaust gas G2 is divided into a plurality of flows by the diversion holes 30d and 30e and the introduction hole 32.

  That is, as shown in FIG. 7, the exhaust gas G <b> 2 flows into the intake passage 202 from the vicinity of the front edge of the partition wall portion 3 through the ten large-diameter branch holes 30 d. Further, the exhaust gas G2 flows into the intake passage 202 from the rear side portion of the flow dividing hole 30d in the partition wall portion 3 through the six small diameter dividing holes 30e. Further, the exhaust gas G <b> 2 flows into the intake passage 202 from the periphery of the valve shaft insertion hole 31 in the partition wall 3 through the three introduction holes 32. As described above, the exhaust gas G <b> 2 is divided into a plurality of flows and flows into the intake passage 202.

  The exhaust gas G <b> 2 that has flowed in joins the fresh air gas G <b> 1 in the intake passage 202. The fresh air gas G3 mixed with the exhaust gas G2 flows out from the fresh air gas outlet 201 to the intake passage 710 of the intake pipe 71. The fresh air gas G3 is introduced into the engine 94 via the intake system 90 shown in FIG.

<Effect>
Next, the effect of the gas mixing apparatus of this embodiment is demonstrated. As shown in FIG. 2, the gas mixing device 1 of this embodiment and the EGR valve assembly 8 share the housing 2. That is, the gas mixing device 1 and the EGR valve assembly 8 are integrated via the housing 2. For this reason, compared with the case where the gas mixing apparatus 1 and the EGR valve assembly 8 are separate bodies, the number of apparatuses constituting the intake / exhaust system 9 shown in FIG. 1 is reduced. Therefore, the configuration of the intake / exhaust system 9 can be simplified.

  Further, according to the gas mixing device 1 of the present embodiment, as shown in FIG. 7, when viewed from the upper side (downstream side in the passage length direction of the EGR passage 21), the plurality of introduction holes 32 are radially inward of the junction 211. Is arranged. In other words, when viewed from the intake passage 202, the plurality of introduction holes 32 and the merging port 211 are arranged in series in the vertical direction. For this reason, the exhaust gas G2 flowing into the intake passage 202 via the plurality of introduction holes 32 is unlikely to stall. Therefore, the exhaust gas G2 tends to reach the fresh air gas G1 in the vicinity of the radial center portion of the intake passage 202. Therefore, the exhaust gas G2 and the fresh air gas G1 can be sufficiently mixed.

  Further, according to the gas mixing device 1 of the present embodiment, as shown in FIG. 4, the exhaust gas G2 having a high flow velocity flowing along the valve shaft 800 of the poppet valve 80 flows in the flow direction (the direction from the lower side to the upper side). The air can be introduced into the intake passage 202 from the plurality of introduction holes 32 without changing the above. For this reason, exhaust gas G2 and fresh air gas G1 can be sufficiently mixed.

  Further, the exhaust gas G2 is at a higher temperature than the fresh air gas G1. For this reason, temperature unevenness is likely to occur in the fresh air gas G3 mixed with the exhaust gas G2. In particular, a large temperature difference occurs between the fresh air gas G3 (high temperature) in the radially outer portion of the intake passage 202 and the fresh air gas G3 (low temperature) near the radial center portion of the intake passage 202. Cheap. In this regard, according to the gas mixing device 1 of the present embodiment, the exhaust gas G2 easily reaches the fresh air gas G1 in the vicinity of the central portion in the radial direction of the intake passage 202. Therefore, temperature unevenness is less likely to occur in the fresh air gas G3 mixed with the exhaust gas G2.

  Further, according to the gas mixing device 1 of the present embodiment, as shown in FIGS. 3 and 4, the intake passage 202 and the EGR passage 21 extend in directions orthogonal to each other. That is, the extending direction of the EGR passage 21 faces the radial center of the intake passage 202. For this reason, the exhaust gas G2 easily reaches the fresh air gas G1 in the vicinity of the central portion in the radial direction of the intake passage 202. Therefore, the exhaust gas G2 and the fresh air gas G1 can be sufficiently mixed.

  Further, according to the gas mixing device 1 of the present embodiment, as shown in FIG. 7, the exhaust gas G2 is supplied from the EGR passage 21 to the intake passage 202 via the plurality of introduction holes 32 and the plurality of diversion holes 30d and 30e. To be introduced. Here, when viewed from the upper side (downstream side of the EGR passage 21 in the passage length direction), the plurality of flow dividing holes 30 d and 30 e are disposed on the radially outer side of the junction port 211. Therefore, as shown in FIG. 4, the exhaust gas G <b> 2 introduced into the intake passage 202 from the plurality of flow dividing holes 30 d and 30 e needs to be detoured in the circumferential direction along the outer peripheral surface of the partition wall portion 3. Therefore, compared with the exhaust gas G2 introduced into the intake passage 202 from the plurality of introduction holes 32, the exhaust gas G2 introduced into the intake passage 202 from the plurality of flow dividing holes 30d and 30e has a lower flow rate. Therefore, according to the gas mixing device 1 of the present embodiment, the high-speed exhaust gas G2 via the plurality of introduction holes 32 can be mixed with the fresh air gas G1 in the vicinity of the central portion in the radial direction of the intake passage 202. In addition, the low-speed exhaust gas G2 passing through the plurality of flow dividing holes 30d and 30e can be mixed with the fresh air gas G1 in the radially outer portion of the intake passage 202.

  Further, according to the gas mixing device 1 of the present embodiment, as shown in FIGS. 4 and 7, the exhaust gas G2 flows from the EGR passage 21 to the intake passage 202 via the plurality of flow dividing holes 30d and 30e of the partition wall 3. To be introduced. Here, the plurality of flow dividing holes 30d and 30e are distributed in the front-rear direction (passage length direction of the intake passage 202) and the circumferential direction. For this reason, according to the gas mixing apparatus 1 of this embodiment, the dispersion | variation in the introduction amount of the exhaust gas G2 in the front-back direction and the circumferential direction can be suppressed. Therefore, the exhaust gas G2 and the fresh air gas G1 can be sufficiently mixed.

  Further, the exhaust gas G2 is at a higher temperature than the fresh air gas G1. For this reason, temperature unevenness is likely to occur in the fresh air gas G3 mixed with the exhaust gas G2. In this regard, according to the gas mixing device 1 of the present embodiment, the exhaust gas G2 can be divided into small chunks and introduced into the intake passage 202 as compared with the case where the flow dividing holes 30d and 30e are single. For this reason, the heat transfer area of the exhaust gas G2 with respect to the fresh air gas G1 becomes large. Therefore, temperature unevenness is less likely to occur in the fresh gas G1 mixed with the exhaust gas G2.

  In addition, in the intake passage 202, the exhaust gas G2 introduced from the upstream diversion hole 30d is in contact with the fresh air gas G1 more than the exhaust gas G2 introduced from the downstream diversion hole 30e ( The time from when the exhaust gas G2 comes into contact with the fresh air gas G1 until it is introduced into the engine 94 shown in FIG. For this reason, the exhaust gas G2 introduced from the upstream diversion hole 30d is more likely to be mixed with the fresh air gas G1 than the exhaust gas G2 introduced from the downstream diversion hole 30e.

  In this regard, according to the gas mixing device 1 of the present embodiment, as shown in FIG. 7, the opening area of the flow dividing holes 30d and 30e is larger on the front side than on the rear side. That is, the opening areas of the diversion holes 30d and 30e with respect to the intake passage 202 are set so that “the sum of the ten diversion holes 30d> the sum of the six diversion holes 30e”. For this reason, the introduction amount of the exhaust gas G2 into the intake passage 202 is “the sum of the ten branch holes 30d> the sum of the six branch holes 30e”. Therefore, the larger the amount of exhaust gas G2 introduced, the longer the contact time with the fresh air gas G1. Therefore, the exhaust gas G2 and the fresh air gas G1 can be sufficiently mixed. Further, temperature unevenness is less likely to occur in the fresh gas G3 mixed with the exhaust gas G2.

  Further, as shown in FIGS. 4 and 5, the partition wall 3 is accommodated in the accommodating chamber 20, that is, in the housing 2. For this reason, the partition part 3 can be protected from the impact from the outside. As shown in FIG. 6, the partition wall 3 is a separate body from the housing 2. Further, the valve shaft insertion hole 31, the plurality of introduction holes 32, and the plurality of flow dividing holes 30 d and 30 e are formed in the partition wall portion 3. For this reason, the valve shaft insertion hole 31, the plurality of introduction holes 32, and the plurality of flow dividing holes 30 d and 30 e can be easily arranged in the partition wall portion 3.

<Others>
The embodiment of the gas mixing apparatus of the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  For example, the positions, dimensions, and ranges of the flow dividing holes 30d and 30e and the introduction hole 32 in the partition wall 3 are not particularly limited. The section from 0 ° position to 180 ° position when passing through 90 ° position (forward direction section) shown in FIG. 7 and the section from 0 ° position to 180 ° position when passing through 270 ° position (reverse) The position, size, and range of the diversion holes 30d and 30e and the introduction hole 32 may be different. For example, the flow dividing holes 30d and 30e and the introduction hole 32 may be unevenly distributed only in the forward direction section or only in the reverse direction section. This makes it easy to form a swirling flow of the exhaust gas G2 in the intake passage 202. For this reason, exhaust gas G2 and fresh air gas G1 can be sufficiently mixed. Further, the plurality of flow dividing holes 30d and 30e may be arranged in a lattice shape in the partition wall portion 3. Further, the plurality of flow dividing holes 30 d and 30 e may be arranged on the entire partition wall portion 3.

  Moreover, you may produce the partition part 3 shown in FIG. 6 using the board | plate material of a commercially available punching metal. That is, the cylindrical partition wall 3 may be produced by rounding a punching metal plate. If it carries out like this, the manufacturing cost of the partition part 3 can be reduced.

  Moreover, you may arrange | position the slope-shaped control part which protrudes to radial inside at the position corresponding to the flow-dividing holes 30d and 30e in the internal peripheral surface of the storage chamber 20 shown in FIG.4, FIG.6. The outflow direction of the exhaust gas G2 with respect to the intake passage 202 may be oriented in a desired direction (any direction including at least one of the passage length direction, the circumferential direction, and the radial direction of the intake passage 202). . In this way, the exhaust gas G2 and the fresh air gas G1 can be sufficiently mixed.

  The restricting portion may restrict the outflow direction from the diversion holes 30d and 30e so that the outflow direction of the exhaust gas G2 faces the circumferential direction on the upstream side of the intake passage 202 than on the downstream side. Thus, the exhaust gas G2 can be mainly introduced into the radially outer portion of the fresh air gas G1 on the upstream side of the intake passage 202. Further, on the downstream side of the intake passage 202, the exhaust gas G2 can be mainly introduced into the radially intermediate portion of the fresh air gas G1 (the portion between the radially central portion and the radially outer portion). . That is, the introduction direction of the exhaust gas G2 can be distributed stepwise in the radial direction from the upstream side to the downstream side of the intake passage 202.

  Further, the partition wall 3 shown in FIG. 6 may be made of a plurality of divided bodies instead of a single body. For example, the partition wall portion 3 is formed by combining a front partition wall having semicircular notches at both ends in the vertical direction of the rear edge and a rear partition wall having semicircular cutout portions at both ends in the vertical direction of the front edge. May be produced. In this case, the insertion hole of the boss portion 20c is formed by combining the pair of front and rear cutouts at the upper end. Moreover, the valve shaft insertion hole 31 is formed by combining the pair of front and rear cutouts at the lower end. The front partition may be formed integrally with the intake pipe 70. Further, the rear partition wall may be integrally formed on the inner peripheral surface of the storage chamber 20. In this way, the front partition and the rear partition can be combined by assembling the housing 2 and the intake pipe 70. Therefore, the partition wall 3 can be installed simultaneously with the assembly of the housing 2 and the intake pipe 70.

  Further, the gas mixing device 1 may be separate from the EGR valve assembly 8. In this case, the housing 2 may be tubular, such as the intake pipes 70 and 71. In this case, the EGR pipe having the EGR passage 21 may be arranged in a double cylinder shape on the radially outer side of the tubular housing 2 having the intake passage 202. Then, the partition wall 3 may be disposed on the tube wall of the housing 2. That is, the flow dividing holes 30 d and 30 e and the introduction hole 32 may be provided in the tube wall of the housing 2. The valve disposed in the EGR valve assembly 8 may be a butterfly valve.

  Further, the gas mixing device 1 may be disposed near the HPL-EGR valve 921 in FIG. In this case, the fresh air gas G3 on the outlet side of the throttle valve 903 corresponds to the “new air gas” of the present invention. Further, the arrangement direction of the gas mixing device 1 (the extending direction of the intake passage 202 and the EGR passage 21) is not particularly limited. For example, the upper side in FIG. 2 may be the lower side, the front side, the rear side, the right side, the left side, and the like.

1: Gas mixing device.
2: housing, 20: storage chamber, 200: fresh air inlet, 201: fresh air outlet, 202: intake passage, 20a: step, 20b: convex portion, 20c: boss portion, 21: EGR passage, 210 : Exhaust gas inlet, 211: junction, 22: spring accommodating chamber.
3: partition part, 3a: notch part, 3b: convex part, 30d: diversion hole, 30e: diversion hole, 31: valve shaft insertion hole, 32: introduction hole.
70: Intake pipe, 700: Intake passage, 71: Intake pipe, 710: Intake passage.
8: EGR valve assembly, 80: Poppet valve, 800: Valve shaft, 800a: Flange, 801: Valve body, 81: Valve seat, 82: Spring, 83: Motor, 830: Motor side shaft.
9: intake / exhaust system, 90: intake system, 900: intake side turbo bypass valve, 901: intercooler switching valve, 902: intercooler, 903: throttle valve, 91: exhaust system, 910: exhaust side turbo bypass valve, 911: exhaust Brake valve, 912: DPF, 913: Exhaust throttle valve, 92: HPL-EGR system, 920: EGR cooler switching valve, 921: HPL-EGR valve, 922: EGR cooler, 93: LPL-EGR system, 930: Intake port 931: LPL-EGR valve, 932: EGR cooler, 94: engine, 95: first turbocharger, 96: second turbocharger.
G1: fresh air gas, G2: exhaust gas, G3: fresh air gas.

Claims (3)

A housing in which an intake passage through which fresh gas flows and an EGR passage that introduces exhaust gas into the intake passage and has a merging port at a downstream end and in which a poppet valve capable of adjusting the flow rate of the exhaust gas is disposed When,
A partition having a valve shaft insertion hole that is disposed between the junction and the intake passage and through which the valve shaft of the poppet valve is inserted, and an introduction hole that opens to the intake passage;
With
The intake passage and the EGR passage extend in directions intersecting each other,
When viewed from the passage length direction of the EGR passage, the valve shaft insertion hole and the introduction hole are disposed on the radially inner side of the merging port ,
The partition wall is separate from the housing,
The gas mixing device in which the valve shaft insertion hole and the introduction hole are formed in the partition wall . The partition portion has a plurality of flow dividing holes that open to the intake passage,
2. The gas mixing device according to claim 1, wherein the plurality of flow dividing holes are disposed on a radially outer side of the merging port when viewed from the passage length direction of the EGR passage. The housing has a housing chamber in which the intake passage and the partition wall are housed radially inside,
The gas mixing apparatus according to claim 1, wherein the EGR passage is connected to the accommodation chamber from the outside in the radial direction.

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