JP2019002303A - EGR cooler bypass valve - Google Patents

Abstract

To improve the linear controllability of an EGR gas temperature by using an EGR cooler bypass valve to an EGR cooler and a bypass passage.SOLUTION: A bypass valve 1 comprises: a cooler flow passage 12 for making a cooler gas passing EGR coolers 3, 9 flow: a bypass passage 13 for making a bypass gas passing a bypass passage 4 flow; a cooler valve body 15; a bypass valve body 16; valve shafts 17 of both the valve bodies 15, 16; and a gas flow rate adjustment structure. The gas flow rate adjustment structure eliminates imbalance between a cooler gas flow rate change in a range in the vicinity of the full-opening of the cooler valve 15 when the cooler valve body 15 is valve-closed, and the bypass valve body 16 is valve-opened, and a bypass gas flow rate change in a range in the vicinity of the full-closing of the bypass valve body 16, and eliminates imbalance between a bypass gas flow rate change in a range in the vicinity of the full-opening of the bypass valve body 16 when the bypass valve body 16 is valve-closed from a full valve-opening position, and the cooler valve body 15 is valve-opened from a full valve-closing position, and a cooler gas flow rate change in a range in the vicinity of the full-closing of the cooler valve body 15.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an EGR cooler bypass valve that is used together with an EGR cooler and simultaneously adjusts an EGR gas flow rate that passes through the EGR cooler and an EGR gas flow rate that passes through a bypass passage that bypasses the EGR cooler.

  Conventionally, as this type of technology, for example, a technology (valve unit) described in Patent Document 1 below is known. As a technique similar to this, there is an EGR cooler unit manufactured by the present applicant. FIG. 10 is a sectional view schematically showing the EGR cooler unit 52. The EGR cooler unit 52 is provided in the middle of the EGR passage (not shown), and the cooler passage 53, the bypass passage 54 bypassing the cooler passage 53, the inlet 53a of the cooler passage 53, and the inlet 54a of the bypass passage 54 merge. A cooler casing 55 including a junction 56, an inlet pipe 57 connected to the junction 56, a bypass valve 51 connected to an outlet 53b of the cooler passage 53 and an outlet 54b of the bypass passage 54, and an outlet of the bypass valve 51 And an outlet pipe 58 connected to the side. The cooler passage 53 is provided with a heat exchanger 59 through which engine coolant flows. In the EGR cooler unit 52, an EGR cooler is configured by the cooler passage 53 and the heat exchanger 59. The inlet pipe 57 and the outlet pipe 58 are each connected to the EGR passage.

  In FIG. 11, the bypass valve 51 is shown by the BB sectional drawing of FIG. As shown in FIGS. 10 and 11, the bypass valve 51 includes a valve casing 61. The valve casing 61 includes a cooler flow path 62 that communicates with the cooler passage 53 and a bypass flow path 63 that communicates with the bypass passage 54, and the cooler flow path 62 and the bypass flow path 63 are partitioned via a partition wall 64. A cooler valve body 65 is rotatably provided in the cooler flow path 62, and a bypass valve body 66 is rotatably provided in the bypass flow path 63. As shown in FIGS. 10 and 11, both valve bodies 65 and 66 are butterfly valve bodies, and are fixed with a phase shifted by “80 °” with respect to one valve shaft 67. Therefore, as shown in FIG. 11, when the cooler valve body 65 is disposed at the fully closed position, the bypass valve body 66 is disposed at the fully open position, and the EGR gas is passed through the bypass passage 54 and the bypass flow path in the EGR cooler unit 52. It flows through 63. On the other hand, when the cooler valve body 65 is disposed at the fully open position, the bypass valve body 66 is disposed at the fully closed position, and EGR gas flows through the cooler passage 53 and the cooler passage 62 in the unit 52.

JP 2009-250100 A

  By the way, the conventional bypass valve 51 in the EGR cooler unit 52 is for selectively switching all of the EGR gas flowing through the EGR passage between a flow passing through the cooler passage 53 and a flow passing through the bypass passage 54. Have been used. On the other hand, in recent years, in order to improve the temperature controllability of the EGR gas introduced into the engine, there is an increasing demand for linearly controlling the temperature of the EGR gas flowing out from the EGR cooler unit 52.

  However, the conventional bypass valve 51 is used for the EGR cooler unit 52 as it is, and the EGR gas temperature is arbitrarily controlled by disposing the valve bodies 65 and 66 at the fully closed position, the fully opened position, and other intermediate openings. Even if it tried, it was difficult to obtain linear controllability about EGR gas temperature. An example of the controllability will be described below with reference to the graphs of FIGS. FIG. 12 shows the relationship of the temperature of the EGR gas (gas temperature) at the gas outlet E3 of the EGR cooler unit 52 with respect to the opening degree of the cooler valve body 65 and the bypass valve body 66 (the temperature of the EGR gas is 370 ° C., the flow rate is 20 g / It is a graph which shows the result in the case of s). FIG. 13 is a graph showing the relationship of the diversion ratio of the EGR cooler unit 52 with respect to the same opening degree (result when the flow rate of the EGR gas is 20 g / s and 370 ° C.). Here, the “diversion ratio” means the ratio (ratio) of the gas flow rate that has passed through the cooler flow path 62 with respect to the entire gas flow rate downstream of the bypass valve 51 in FIG. 10. FIG. 14 is a graph showing the relationship between pressure loss (differential pressure) and the same opening degree (results when the flow rate of EGR gas is 20 g / s and temperatures are 200 ° C. and 370 ° C.). In FIG. 14, a solid line with a square means that the gas temperature is 200 ° C., and a solid line with a triangle means that the gas temperature is 370 ° C. Here, “pressure loss (differential pressure)” means the difference between the gas pressure at the gas inlet E0 and the gas pressure at the gas outlet E3 of the EGR cooler unit 52 in FIG.

  Here, in FIG. 12, the gas outlet temperature does not show a linear change. In particular, in the vicinity range (the portion of the ellipse S1 in FIG. 12) where the bypass side is fully open (cooler side fully closed) and the vicinity range (the portion of the ellipse S2 in FIG. 12) where the cooler side is fully open (bypass side fully closed) The change in outlet temperature is not linear. This tendency is the same also about the shunt ratio shown in FIG. Further, as shown in FIG. 14, the pressure loss (differential pressure) tends to increase rapidly in the vicinity of the bypass side fully open and the cooler side fully open.

  As described above, the linearity of the gas temperature, the flow ratio, and the pressure loss is deteriorated in the vicinity of the bypass side full open and the cooler side full open because the change in the gas flow rate in the vicinity of the full open position of each valve body 65, 66 is relatively small. Therefore, it is considered that the change in gas flow rate in the vicinity range of the fully closed position is relatively large. In FIG. 15, the relationship of the gas flow rate in the cooler flow path 62 and the bypass flow path 63 with respect to the same opening degree is shown with a graph. In FIG. 15, the broken line indicates the gas flow rate (cooler flow rate) of the cooler flow path 62, and the solid line indicates the gas flow rate (bypass flow rate) of the bypass flow path 63. As shown in FIG. 15, both the cooler flow path 62 and the bypass flow path 63 have almost no change in gas flow rate in the vicinity of the bypass side full open and the cooler side full open (the ellipses S11 and S12 in FIG. 15). In the vicinity range of the bypass side fully closed and the cooler side fully closed (the portions of ellipses S13 and S14 in FIG. 15), the gas flow rate change is relatively large. For this reason, the total flow rate of the cooler flow rate and the bypass flow rate is not constant and greatly changes in all opening ranges of the valve bodies 65 and 66. This total flow rate tends to decrease in the vicinity range of the bypass side fully open and in the vicinity range of the cooler side fully open, and increase in an intermediate range between the bypass side fully open and the cooler side fully open. Thus, the total flow rate is not constant because the cooler valve body 65 rotates when the cooler valve body 65 rotates from the fully open position to the close direction and the bypass valve body 66 rotates from the fully closed position to the open direction. This is presumably because there is a large or small imbalance between the change in the cooler flow rate in the range near the fully open position and the change in the bypass flow rate in the range near the fully closed position of the bypass valve element 66. Further, when the bypass valve body 66 rotates in the closing direction from the fully opened position and the cooler valve body 65 rotates in the opening direction from the fully closed position, the change in the bypass flow rate in the vicinity of the fully opened position of the bypass valve body 66 is achieved. It is considered that there is a large and small imbalance between the temperature of the cooler valve body 65 and the change in the cooler flow rate in the vicinity of the fully closed position. Thus, it is considered that the difference in the gas flow rate between the flow paths 62 and 63 causes a rapid change in the gas temperature, the flow ratio, and the pressure loss (differential pressure) shown in FIG.

  On the other hand, unlike the above-described bypass valve 51, a three-way valve type bypass valve is known. FIG. 16 is a sectional view of the bypass valve 81. In the bypass valve 81, the valve shaft 88 is disposed in parallel with one end surface of the partition wall 84 in the EGR gas flow direction, and is rotatably supported. The three-way valve body 87 fixed to the valve shaft 88 has a plate-like shape and includes a cooler valve body 87a and a bypass valve body 87b separated into a reverse C shape, and a connecting portion 87c that connects both valve bodies 87a and 87b. The connecting portion 87c is fixed to the valve shaft 88. In a state where the cooler valve body 87 a is disposed at the fully closed position where the cooler valve body 87 a is seated on the cooler valve seat 89, the bypass valve body 87 b is farthest from the bypass valve seat 90 and is disposed at the fully open position where it contacts the partition wall 84. On the contrary, in the state where the bypass valve body 87b is disposed at the fully closed position where the bypass valve body 87b is seated on the bypass valve seat 90, the cooler valve body 87a is farthest from the cooler valve seat 89 and is disposed at the fully opened position corresponding to the partition wall 84. The Even in the EGR cooler unit using the bypass valve 81, it is difficult to obtain linear controllability of the EGR gas temperature.

  An example of the controllability will be described below with reference to the graphs of FIGS. FIG. 17 shows the relationship of the gas temperature at the gas outlet of the EGR cooler unit with respect to the opening degree of the cooler valve body 87a and the bypass valve body 87b (result when the temperature of the EGR gas is 370 ° C. and the flow rate is 20 g / s). It is a graph. FIG. 18 is a graph showing the relationship of the diversion ratio of the EGR cooler unit with respect to the same opening (result when the flow rate of EGR gas is 20 g / s and the temperature is 370 ° C.). FIG. 19 is a graph showing the relationship between pressure loss and the same opening degree (EGR gas flow rate is 20 g / s, temperatures are 200 ° C. and 370 ° C. (compared to the case of a butterfly valve body)). Corresponds to FIG.

  In FIG. 17, the gas outlet temperature does not show a linear change. In particular, in the vicinity range where the bypass side is fully open (cooler side fully closed) and the vicinity range where the cooler side is fully open (bypass side fully closed), the change in gas temperature is large (the ellipses S21 and S22 in FIG. 17). portion). As shown in FIG. 18, this tendency is the same for the diversion ratio. As shown in FIG. 19, the pressure loss also tends to increase in the vicinity of the bypass side full open and the cooler side full open, as in the butterfly valve element.

  As described above, the linearity of the gas temperature, the diversion ratio, and the pressure loss is deteriorated in the vicinity of the fully open position and the fully closed position of the valve bodies 87a and 87b, as with the butterfly valve body. Changes in the gas flow rate (cooler flow rate) of the cooler flow path 85 (see FIG. 16) in the vicinity range and the gas flow rates (bypass flow rate) in the bypass flow path 86 (see FIG. 16) in the vicinity range of the fully closed position of the bypass valve element 87b. This is thought to be because there is a large and small imbalance between changes in Further, it is considered that there is a large and small imbalance between the change in the bypass flow rate in the range near the fully open position of the bypass valve body 87b and the change in the cooler flow rate in the range near the fully closed position of the cooler valve body 87a. Then, it is considered that such a difference in gas flow rate change in the vicinity of the fully open position and the fully closed position causes a change in pressure loss shown in FIG.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an EGR cooler bypass valve that can be used in an EGR cooler and a bypass passage to improve linear controllability of EGR gas temperature. Is to provide.

  In order to achieve the above object, the invention described in claim 1 is used together with an EGR cooler for cooling EGR gas, and passes through a bypass passage bypassing the EGR cooler and a flow rate of the EGR gas passing through the EGR cooler. An EGR cooler bypass valve that simultaneously adjusts the flow rate of the EGR gas that includes a cooler flow path through which the EGR gas that has passed through the EGR cooler flows, and a bypass flow path through which the EGR gas that has passed through the bypass passage flows. A casing in which a passage and a bypass flow path are partitioned by a partition, a plate-like cooler valve body for opening and closing the cooler flow path, a plate-like bypass valve body for opening and closing the bypass flow path, and a cooler A valve shaft for rotating the valve body and the bypass valve body integrally, and the cooler valve body rotates in the opening direction by rotating the valve shaft in one direction. In both cases, the bypass valve body is rotated in the closing direction and the valve shaft is rotated in the reverse direction, whereby the cooler valve body is rotated in the closing direction and the bypass valve body is rotated in the opening direction. The valve body is opened and closed between a fully open position where the gas flow rate in the cooler flow path is maximized and a fully closed position where the gas flow rate in the cooler flow path is zero, and the bypass valve body is maximized in the gas flow rate in the bypass flow path. In the EGR cooler bypass valve configured to be opened and closed between the fully opened position and the fully closed position where the gas flow rate of the bypass flow path is zero, the cooler valve body rotates in the closing direction from the fully opened position. When the bypass valve body rotates in the opening direction from the fully closed position, the gas flow rate change in the cooler flow path in the range near the fully open position of the cooler valve body and the bypass flow path in the range near the fully closed position of the bypass valve body Gas flow change and When the bypass valve body rotates in the closing direction from the fully open position and the cooler valve body rotates in the opening direction from the fully closed position, the bypass in the vicinity of the fully open position of the bypass valve element is eliminated. It is intended to have a gas flow rate adjusting structure for eliminating an imbalance between a gas flow rate change in the flow channel and a gas flow rate change in the cooler flow channel in the vicinity of the fully closed position of the cooler valve body.

  According to the configuration of the invention, when the cooler valve body or the bypass valve body is closed in the closing direction from the fully open position, that is, when the bypass valve body or the cooler valve body is opened in the opening direction from the fully closed position, The imbalance between the gas flow rate change in the cooler flow path and the gas flow rate change in the bypass flow path is eliminated.

  In order to achieve the above object, according to a second aspect of the present invention, in the first aspect of the present invention, the gas flow rate adjusting structure is configured such that the fully open position of the cooler valve body and the fully open position of the bypass valve body are respectively set to EGR gas. It is intended to be moved from the state parallel to the central axis of the casing in the flow direction by a predetermined angle in the closing direction.

  According to the configuration of the above invention, in addition to the operation of the invention described in claim 1, the unbalance of the gas flow rate change is eliminated by merely moving the fully opened positions of the cooler valve body and the bypass valve body by a predetermined angle in the closing direction. Is done.

  In order to achieve the above object, the invention described in claim 3 is the invention described in claim 2, wherein the cooler valve body and the bypass valve body have a rotation angle of 50 between the fully closed position and the fully open position. It is intended that the angle is set to an angle of ° to 70 °.

  According to the configuration of the invention, in addition to the operation of the invention according to claim 2, the rotation angle between the fully closed position and the fully opened position of the cooler valve body and the bypass valve body is an angle of 50 ° to 70 °. The gas flow rate change imbalance is eliminated simply by setting to.

  In order to achieve the above object, according to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the cooler valve body and the bypass valve body are in contact with the casing at least in the fully closed position. The purpose is that.

  According to the configuration of the above invention, in addition to the operation of the invention according to any one of claims 1 to 3, the cooler valve body and the bypass valve body come into contact with the casing at least in the fully closed position, so that the valve bodies The heating by the EGR gas is relaxed.

  In order to achieve the above object, the invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the cooler valve body and the bypass valve body are butterfly type valve bodies, and the valve shaft is the cooler. The cooler valve element is fixed to the valve shaft in the cooler flow path, and the bypass valve element is fixed to the valve shaft in the bypass flow path. The intent is that

  According to the structure of the said invention, the effect | action equivalent to the invention in any one of Claims 1 thru | or 4 is acquired about the EGR cooler bypass valve which uses a butterfly-type valve body.

  In order to achieve the above object, according to a sixth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the cooler valve body and the bypass valve body are integrally formed via a connecting portion. To form a three-way valve body, the valve shaft is arranged in parallel with one end face of the partition wall in the EGR gas flow direction, the three-way valve body is fixed to the valve shaft at the connecting portion, and the cooler valve body Is arranged so that it can swing around the valve shaft in the cooler flow path, and the bypass valve body is placed so as to swing around the valve shaft in the bypass flow path.

  According to the structure of the said invention, the effect | action equivalent to the invention in any one of Claims 1 thru | or 4 is acquired about the EGR cooler bypass valve which uses a three-way valve-type valve body.

  According to the first aspect of the present invention, linear controllability of the EGR gas temperature can be improved by using the EGR cooler bypass valve for the EGR cooler and the bypass passage.

  According to the invention of the second aspect, in addition to the effect of the invention of the first aspect, it is only necessary to change the mounting angle of the cooler valve body and the bypass valve body with respect to the valve shaft for the current EGR cooler bypass valve. The EGR cooler bypass valve of the present invention can be easily obtained.

  According to the third aspect of the present invention, an effect equivalent to that of the second aspect of the invention can be obtained.

  According to the invention described in claim 4, in addition to the effects of the invention described in any one of claims 1 to 3, heat resistance reliability can be secured as an EGR cooler bypass valve.

  According to the fifth aspect of the present invention, the EGR cooler bypass valve using the butterfly valve body can achieve the same effects as the first aspect of the present invention.

  According to the invention described in claim 6, the EGR cooler bypass valve using the three-way valve body can obtain the same effect as the invention described in any one of claims 1 to 4.

A sectional view showing an outline of an EGR cooler unit provided with an EGR cooler bypass valve (bypass valve) concerning a 1st embodiment. Sectional drawing which concerns on 1st Embodiment and shows a bypass valve. The AA sectional view taken on the line of FIG. 1 which shows a bypass valve concerning 1st Embodiment. The graph which concerns on 1st Embodiment and shows the relationship of the gas flow rate which passes a bypass flow path and a cooler flow path with respect to the opening degree of a bypass valve body and a cooler valve body, and gas outlet temperature. Sectional drawing according to FIG. 3 which concerns on 2nd Embodiment and shows a bypass valve. Sectional drawing which concerns on 3rd Embodiment and shows the outline of the EGR cooler unit provided with the bypass valve. Sectional drawing which concerns on 3rd Embodiment and shows a bypass valve. Sectional drawing according to FIG. 7 which concerns on 4th Embodiment and shows a bypass valve. Sectional drawing according to FIG. 7 which concerns on 5th Embodiment and shows a bypass valve. Sectional drawing which concerns on a prior art example and shows the outline of an EGR cooler unit. The BB sectional drawing of FIG. 10 which concerns on a prior art example and shows a bypass valve. The graph which shows the relationship of the gas temperature in the gas exit of an EGR cooler unit with respect to the opening degree of a cooler valve body and a bypass valve body concerning a prior art example. The graph which shows the relationship of the shunt ratio of the EGR cooler unit with respect to the opening degree of each valve body concerning a prior art example. The graph which shows the relationship of the pressure loss (differential pressure) with respect to the opening degree of each valve body concerning a prior art example. The graph which shows the relationship between the cooler flow volume with respect to the opening degree of each valve body, and a bypass flow volume concerning a prior art example. Sectional drawing which shows a bypass valve in connection with a prior art example. The graph which shows the relationship of the gas temperature in the gas exit of an EGR cooler unit with respect to the opening degree of a cooler valve body and a bypass valve body concerning a prior art example. The graph which shows the relationship of the shunt ratio of the EGR cooler unit with respect to the opening degree of each valve body concerning a prior art example. The graph which shows the relationship of the pressure loss with respect to the opening degree of each valve body concerning a prior art example.

<First Embodiment>
Hereinafter, a first embodiment in which an EGR cooler bypass valve of the present invention is embodied will be described in detail with reference to the drawings.

  FIG. 1 is a schematic sectional view of an EGR cooler unit 2 including an EGR cooler bypass valve (hereinafter simply referred to as “bypass valve”) 1 according to this embodiment. The EGR cooler unit 2 is provided in the middle of the EGR passage (not shown), and the cooler passage 3, the bypass passage 4 bypassing the cooler passage 3, the inlet 3a of the cooler passage 3, and the inlet 4a of the bypass passage 4 join together. A cooler casing 5 including a merging portion 6, an inlet pipe 7 connected to the merging portion 6, a bypass valve 1 connected to an outlet 3 b of the cooler passage 3 and an outlet 4 b of the bypass passage 4, And an outlet pipe 8 connected to the outlet side. The cooler passage 3 is provided with a heat exchanger 9 through which engine coolant flows. In the EGR cooler unit 2, an EGR cooler is configured by the cooler passage 3 and the heat exchanger 9. The inlet pipe 7 and the outlet pipe 8 are each connected to an EGR passage. Here, the EGR gas flowing into the inlet pipe 7 is cooled by the heat exchanger 9 by passing through the cooler passage 3.

  FIG. 2 is a sectional view of the bypass valve 1. In FIG. 3, the bypass valve 1 is shown by the AA sectional view taken on the line of FIG. The bypass valve 1 is used in the EGR cooler unit 2 and passes through the EGR gas flow rate (gas flow rate) passing through the EGR cooler (cooler passage 3 and heat exchanger 9) and the bypass passage 4 bypassing the cooler passage 3. It is a valve that adjusts the gas flow rate at the same time. The bypass valve 1 includes a valve casing 11. The valve casing 11 includes a cooler flow path 12 that communicates with the outlet 3 b of the cooler passage 3 and a bypass flow path 13 that communicates with the outlet 4 b of the bypass passage 4. It is partitioned through. Here, the partition wall 14 is formed in parallel with the central axis L1 (see FIG. 2) of the valve casing 11 in the EGR gas flow direction. The EGR gas that has passed through the cooler passage 3 flows through the cooler passage 12. The EGR gas that has passed through the bypass passage 4 flows through the bypass passage 13. A plater-shaped cooler valve body 15 for opening and closing the cooler channel 12 is disposed in the cooler channel 12. A plate-like bypass valve body 16 for opening and closing the bypass passage 13 is disposed in the bypass passage 13. As shown in FIGS. 2 and 3, in this embodiment, the cooler valve body 15 and the bypass valve body 16 are each a butterfly valve body and are fixed to one valve shaft 17. The valve shaft 17 is disposed through the cooler flow path 12, the partition wall 14 and the bypass flow path 13, and is rotatably supported by the valve casing 11. The cooler valve body 15 is fixed to the valve shaft 17 in the cooler flow path 12, and the bypass valve body 16 is fixed to the valve shaft 17 in the bypass flow path 13. As a result, the cooler valve body 15 and the bypass valve body 16 are integrally rotated by the valve shaft 17. The cooler valve body 15 and the bypass valve body 16 are fixed to the valve shaft 17 in a state where the phases are shifted from each other. In this bypass valve 1, by rotating the valve shaft 17 in one direction, the cooler valve body 15 rotates in the opening direction, and the bypass valve body 16 rotates in the closing direction, so that the valve shaft 17 rotates in the reverse direction. The cooler valve body 15 rotates in the closing direction and the bypass valve body 16 rotates in the opening direction. In order to open and close the valve bodies 15 and 16, the valve shaft 17 is drivingly connected to an actuator 10 such as a motor as shown in FIG. Such a basic configuration is the same as that of the conventional example. Therefore, when the cooler valve body 15 is disposed at the fully closed position, the bypass valve body 16 is disposed at the fully opened position, and the EGR gas flows through the bypass passage 4 and the bypass passage 13. Further, when the cooler valve body 15 is disposed at the fully open position, the bypass valve body 16 is disposed at the fully closed position, and EGR gas flows through the cooler passage 3 and the cooler passage 12. In this embodiment, the valve bodies 15 and 16 can be switched between a fully closed position and a fully opened position, respectively, and can be disposed at any intermediate opening between the fully closed position and the fully opened position. By controlling the opening degree of both valve bodies 15 and 16 in this way, the gas flow rate passing through the cooler flow path 12 and the gas flow rate passing through the bypass flow path 13 are respectively adjusted, and the EGR gas flowing out from the outlet pipe 8 is controlled. The temperature (gas outlet temperature) is arbitrarily controlled.

  Here, in the EGR cooler unit 2, in order to accurately control the gas outlet temperature of the outlet pipe 8 to an arbitrary temperature, the gas outlet temperature can be controlled linearly with respect to the opening changes of both valve bodies 15 and 16. It is necessary to make it. Therefore, the bypass valve 1 of this embodiment has the following technical features. In FIG. 3, the bypass valve element 16 positioned in the bypass flow path 13 is indicated by a solid line, and the cooler valve element 15 positioned below the partition wall 14 is indicated by a broken line. As shown in FIG. 3, the bypass passage 13 is provided with a bypass valve seat 18 for the bypass valve body 16, and the cooler passage 12 is provided with a cooler valve seat 19 for the cooler valve body 15. . That is, the cooler valve body 15 contacts the valve casing 11 via the cooler valve seat 19 in the fully closed position, and the bypass valve body 16 passes through the bypass valve seat 18 in the fully closed position. To come into contact. In FIG. 3, the bypass valve body 16 is disposed at the fully open position farthest from the bypass valve seat 18, and the cooler valve body 15 is disposed at the fully closed position seated on the cooler valve seat 19. That is, when the cooler valve body 15 is disposed at the fully closed position, the bypass valve body 16 is disposed at the fully opened position. 3, the fully opened position of the bypass valve body 16 is a position rotated by a predetermined angle θK in the closing direction from a position parallel to the central axis L1 of the valve casing 11 (fully opened position of the bypass valve body 66 of the conventional example). Is set. Thereby, the rotation angle between the fully closed position and the fully open position of the bypass valve body 16 is set to a predetermined improvement angle θM. This setting is the same for the cooler valve body 15, and the rotation angle between the fully closed position and the fully open position of the cooler valve body 15 is set to a predetermined improvement angle θM. That is, in the conventional example, as shown in FIG. 11, the rotation angle between the fully closed position and the fully open position of each of the valve bodies 65 and 66 is “80 °”. Here, the fully open position of the cooler valve body 65 is a position where the cooler valve body 65 is parallel to the central axis L1, and the fully open position of the bypass valve body 66 is a position where the bypass valve body 66 is parallel to the central axis L1. Met. On the other hand, in the present embodiment, the fully open position of the cooler valve body 15 and the fully open position of the bypass valve body 16 are predetermined in a closing direction from a position parallel to the central axis L1 of the valve casing 11 in the EGR gas flow direction. Is moved by an angle θK. Thereby, the rotation angle between the fully closed position and the fully open position of each valve body 15 and 16 is set to the predetermined improvement angle θM. In this embodiment, the predetermined angle θK is set to “10 °”. The predetermined angle θK can be set in a range of “10 ° to 25 °”. Further, the predetermined improvement angle θM is set to “70 °”. The improved angle θM can be set in a range of “50 ° to 70 °”. In this embodiment, these configurations correspond to an example of the gas flow rate adjusting structure of the present invention.

  This gas flow rate adjusting structure is a range in the vicinity of the fully open position of the cooler valve body 15 when the cooler valve body 15 rotates in the closing direction from the fully open position and the bypass valve body 16 rotates in the opening direction from the fully closed position. Thus, a large and small imbalance between the change in the gas flow rate in the cooler flow path 12 and the change in the gas flow rate in the bypass flow path 13 in the vicinity of the fully closed position of the bypass valve body 16 is eliminated. In addition, this gas flow rate adjusting structure is provided at the fully open position of the bypass valve body 16 when the bypass valve body 16 rotates in the closing direction from the fully open position and the cooler valve body 15 rotates in the opening direction from the fully closed position. A large and small imbalance between the change in the gas flow rate of the bypass flow path 13 in the vicinity range and the change in the gas flow rate of the cooler flow path 12 in the vicinity range of the fully closed position of the cooler valve body 15 is eliminated.

  According to the configuration of this embodiment described above, when the cooler valve body 15 or the bypass valve body 16 is closed in the closing direction from the fully open position, the bypass valve body is used for the bypass valve 1 using the butterfly valve body. When the 16 or the cooler valve body 15 opens from the fully closed position in the opening direction, the large and small imbalance between the change in the gas flow rate in the cooler flow path 12 and the change in the gas flow rate in the bypass flow path 13 is eliminated. As a result, by using the bypass valve 1 using the butterfly valve body in the EGR cooler unit 2, that is, by using it in the EGR cooler and the bypass passage 4, the linear controllability of the EGR gas temperature can be improved. it can.

  FIG. 4 is a graph showing the relationship between the gas flow rate passing through the bypass flow path 13 and the cooler flow path 12 and the gas outlet temperature with respect to the opening degree of the bypass valve body 16 and the cooler valve body 15. FIG. 4 shows characteristics (estimated values) of the bypass valve 1 of the present embodiment. In FIG. 4, the solid line with diamonds indicates the flow rate of the cooler passage 12 (cooler flow rate FC), the solid line with squares indicates the flow rate of the bypass passage 13 (bypass flow rate FB), and a solid line with a US mark Indicates the total flow rate (gas flow rate from the outlet pipe 8) FT of both flow paths 12, 13, and the solid line with a circle indicates the gas outlet temperature TO.

  In the conventional example, as shown in FIGS. 12 and 15, there is almost no change in the bypass flow rate in the vicinity of the bypass side full open where the bypass valve body 66 is disposed at the full open position (the portion of the ellipse S11 in FIG. 15). In the vicinity range of the bypass side fully closed (cooler side fully open) where the bypass valve element 66 is disposed at the fully closed position (the portion of the ellipse S14 in FIG. 15), the change in the bypass flow rate was relatively large. That is, the bypass valve body 66 is rotated between a fully open position where the bypass flow rate is maximized and a fully closed position where the bypass flow rate is zero. There is a region where the change in the gas flow rate is relatively small in the range close to the fully open position in the rotation range of the bypass valve element 66, and there is a region where the change in the gas flow rate is relatively large in the range close to the fully closed position. It was.

  On the other hand, as shown in FIG. 15, in the vicinity range of the cooler side full open (the portion of the ellipse S12 in FIG. 15), there is almost no change in the cooler flow rate, and the vicinity range of the cooler side full close (bypass side full open) (in FIG. 15). In the ellipse S13), the change in the cooler flow rate was relatively large. That is, the cooler valve body 65 is rotated between a fully open position where the cooler flow rate is maximum and a fully closed position where the cooler flow rate is zero. There is a region in which the change in gas flow rate is relatively small in the range close to the fully open position in the rotation range of the cooler valve body 15, and there is a region in which the change in gas flow rate is relatively large in the range near the fully closed position. It was.

  That is, when the cooler valve body 65 rotates in the closing direction from the fully open position (also when the bypass valve body 66 rotates in the opening direction from the fully closed position), in the vicinity of the fully open position of the cooler valve body 65. Between the range (portion of ellipse S12 in FIG. 15) and the vicinity range (portion of ellipse S14 in FIG. 15) of the fully closed position of the bypass valve body 66, the change between the change in the cooler flow rate and the change in the bypass flow rate is small. There was an imbalance. Further, when the bypass valve body 66 rotates in the closing direction from the fully open position (also when the cooler valve body 65 rotates in the opening direction from the fully closed position), the bypass valve body 66 is in the vicinity of the fully open position. Even between the range (the portion of ellipse S11 in FIG. 15) and the vicinity of the fully closed position of the cooler valve body 65 (the portion of ellipse S13 in FIG. 15), the change between the change in the bypass flow rate and the change in the cooler flow rate is small. There was an imbalance. Then, due to the unbalance of these gas flow rate changes, as shown in FIG. 12, it was not possible to obtain linear controllability with respect to changes in the gas outlet temperature.

  On the other hand, according to the bypass valve 1 of this embodiment, as shown in FIG. 4, the change in the gas flow rate (cooler flow rate) of the cooler flow path 12 indicated by diamonds and the gas flow rate of the bypass flow path 13 indicated by squares ( The change of the bypass flow rate) became a linear characteristic through the entire opening range. That is, the change in the cooler flow rate and the change in the bypass flow rate are balanced in the vicinity range of the fully open position and the close range of the valve bodies 15 and 16, respectively. As a result, as shown in FIG. 4, the gas outlet temperature TO has a linear characteristic.

  According to the configuration of this embodiment, it is only necessary to move the fully opened positions of the cooler valve body 15 and the bypass valve body 16 in the closing direction by the predetermined angle θK, that is, the fully closed positions of the cooler valve body 15 and the bypass valve body 16. By simply setting the rotation angle between the position and the fully open position to an angle of 50 ° to 70 °, the unbalance of the gas flow rate change is eliminated. For this reason, the bypass valve 1 of this embodiment can be obtained easily only by changing the attachment angle of each valve body 15 and 16 with respect to the valve shaft 17 for the current bypass valve.

  According to the configuration of this embodiment, when the cooler valve body 15 and the bypass valve body 16 are in contact with the valve casing 11 at least in the fully closed position, heating of the valve bodies 15 and 16 by the EGR gas is mitigated. . For this reason, the heat resistance reliability of the bypass valve 1 can be ensured.

Second Embodiment
Next, a second embodiment in which the EGR cooler bypass valve of the present invention is embodied will be described in detail with reference to the drawings.

  In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different points are mainly described.

  This embodiment differs from the first embodiment in terms of the gas flow rate adjustment structure of the present invention. FIG. 5 shows a cross-sectional view of the bypass valve 1 of this embodiment according to FIG. As shown in FIG. 5, in this embodiment, the fully opened position of the bypass valve body 16 is set in a state parallel to the central axis L1 of the bypass valve 1 (fully opened position of the bypass valve body 66 of the conventional example). Thereby, the rotation angle between the fully open position and the fully closed position of the bypass valve body 16 is set to “80 °” as in the conventional example (see FIG. 11). This setting is the same for the cooler valve body 15. In addition, in this embodiment, convex portions 20 having a substantially trapezoidal cross section are provided on the inner peripheral surfaces of the inlet and outlet of the bypass channel 13. These convex portions 20 have curved surfaces 20 a that are inclined toward the bypass valve seat 18. By providing these convex portions 20, the gas flow rate change in the range near the fully open position of the bypass valve body 16 is improved from a relatively small state, and it is configured to have a change substantially equivalent to other opening ranges. Yes. The same applies to the cooler valve body 15 and the cooler flow path 12. This configuration corresponds to an example of the gas flow rate adjusting structure of the present invention.

  With this structure, the cooler valve body 15 rotates in the closing direction from the fully open position, and the gas in the range near the fully open position of the cooler valve body 15 when the bypass valve body 16 rotates in the opening direction from the fully closed position. A large and small imbalance between the flow rate change and the gas flow rate change in the vicinity of the fully closed position of the bypass valve body 16 is eliminated. At the same time, the bypass valve body 16 rotates in the closing direction from the fully open position, and the gas flow rate change in the range near the fully open position of the bypass valve body 16 and the gas flow rate change in the range near the fully closed position of the cooler valve body 15 I try to eliminate the large and small imbalance between the two.

  Thereby, as shown in FIG. 5, in the horizontal state where the bypass valve body 16 is disposed at the fully open position, the first opening area SA between the tip of the bypass valve body 16 and the upper bottom 20b of the convex portion 20 is reduced. The second opening area SB between the inner peripheral surface 18a of the bypass valve seat 18 and the valve shaft 17 is the same. Further, as shown by a two-dot chain line in FIG. 5, the change from the first opening area SA to the third opening area SC when the bypass valve body 16 is slightly rotated in the closing direction from the fully opened position is different. It is almost the same as that of the opening range. Alternatively, the change of the opening area from the intermediate opening to the fully open position is reduced between the fully open position and the fully closed position by reducing the change of the opening area at the intermediate opening by the curved surface 20a of the convex portion 20. Is uniform. Thereby, the gas flow rate change in the range near the fully open position of the bypass valve body 16 becomes substantially the same as the gas flow rate change in the other opening ranges. The same applies to the cooler valve body 15 and the cooler flow path 12.

  Therefore, even with the configuration of the bypass valve 1 of this embodiment, the same operation and effect as the first embodiment can be obtained.

<Third Embodiment>
Next, a third embodiment in which the EGR cooler bypass valve of the present invention is embodied will be described in detail with reference to the drawings.

  This embodiment is different from the above embodiments mainly in the configuration of the bypass valve. FIG. 6 shows a schematic cross-sectional view of the EGR cooler unit 2 including the bypass valve 21 of this embodiment. The configuration of the EGR cooler unit 2 is basically the same as that of each of the embodiments except for the bypass valve 21. In FIG. 7, the bypass valve 21 is shown with sectional drawing. As shown in FIGS. 6 and 7, the bypass valve 21 is a three-way valve, and the valve casing 22 includes a cooler flow path 25 and a bypass flow path that are divided into two branches from a junction 23 through a partition wall 24. 26. On the inner circumferences of the flow paths 25 and 26, curved enlarged diameter curved surfaces 25a and 26a are formed in which the inner diameter gradually increases toward the inlet side (the left side in the figure). A plate-like three-way valve body 27 is disposed in the merge portion 23. As shown in FIG. 7, the three-way valve-type valve body 27 has a plate-like shape and includes a cooler valve body 27a and a bypass valve body 27b that are separated into a reverse C shape, and a connecting portion 27c that connects both valve bodies 27a and 27b. It is integrally formed. The valve shaft 28 is disposed in parallel with one end surface of the partition wall 24, and the three-way valve body 27 is fixed to the valve shaft 28 at its connecting portion 27c. As a result, the three-way valve type valve element 27 swings integrally with the valve shaft 28 as the valve shaft 28 rotates. The cooler valve body 27a is disposed so as to be swingable about the valve shaft 28 in the cooler flow path 25, and the bypass valve body 27b is disposed so as to be swingable about the valve shaft 28 in the bypass flow path 26. . The valve bodies 27a and 27b are configured to open and close the cooler passage 25 and the bypass passage 26 by swinging. Further, as shown in FIG. 6, the valve shaft 28 is drivingly connected to the actuator 10 in order to open and close the three-way valve body 27.

  In FIG. 7, the partition wall 24 has a trapezoidal cross section. A conventional partition wall 84 is shown in the partition wall 24 by a two-dot chain line. As shown in FIG. 7, the partition wall 24 of this embodiment is formed thicker than the partition wall 84 of the conventional example, and has a cooler slope 24a facing the cooler flow path 25 and a bypass slope 24b facing the bypass flow path 26. Have. The valve casing 22 includes a cooler valve seat 29 on which the cooler valve body 27a is seated and a bypass valve seat 30 on which the bypass valve body 27b is seated. In FIG. 7, the cooler valve body 27 a is disposed at the fully open position where it contacts the cooler inclined surface 24 a of the partition wall 24, and the bypass valve body 27 b is disposed at the fully closed position where it sits on the bypass valve seat 30. That is, in the state where the cooler valve body 27a is disposed at the fully open position, the bypass valve body 27b is disposed at the fully closed position. On the contrary, in a state where the bypass valve body 27b is disposed at the fully open position, the cooler valve body 27a is disposed at the fully closed position. With this configuration, the opening angle θV1 between the cooler valve body 27a and the bypass valve body 27b shown in FIG. 7 is enlarged by a predetermined angle θK from the opening angle θV0 (80 °) of the conventional example. Yes. In this embodiment, the predetermined angle θK is set to “24 °” by setting the inclination angle of each inclined surface 24a, 24b with respect to the straight line L2 parallel to the central axis of the valve casing 22 to “24 °”. The opening angle θV1 is set to “104 °”. That is, the fully open positions of the conventional valve bodies 87a and 87b are arranged in parallel with the central axis of the valve casing. On the other hand, in this embodiment, the valve bodies 27a and 27b are set to be inclined at a predetermined angle θK toward the flow paths 25 and 26 with respect to the fully opened positions of the valve bodies 87a and 87b of the conventional example. The Such a configuration corresponds to an example of the gas flow rate adjusting structure of the present invention.

  With this gas flow rate adjusting structure, the fully open position of the cooler valve body 27a and the bypass valve body 27b is set to the maximum position excluding the region where the gas flow rate change is relatively small. With this structure, when the cooler valve element 27a rotates in the closing direction from the fully open position and the bypass valve element 27b rotates in the opening direction from the fully closed position, the cooler flow in the vicinity of the fully open position of the cooler valve element 27a. The large and small imbalance between the change in the gas flow rate in the passage 25 and the change in the gas flow rate in the bypass passage 26 in the vicinity of the fully closed position of the bypass valve element 27b is eliminated. In addition, when the bypass valve element 27b rotates from the fully open position in the closing direction and the cooler valve element 27a rotates in the opening direction from the fully closed position, the bypass flow path in the vicinity of the fully open position of the bypass valve element 27b. The imbalance between the gas flow rate change of 26 and the gas flow rate change of the cooler flow path 25 in the vicinity of the fully closed position of the cooler valve body 27a is eliminated.

  According to this embodiment described above, with respect to the bypass valve 21 using the three-way valve body 27, when the cooler valve body 27a or the bypass valve body 27b is closed from the fully opened position to the closing direction, that is, the bypass valve body. The large and small imbalance between the change in the gas flow rate in the cooler flow path 25 and the change in the gas flow rate in the bypass flow path 26 when the valve 27b or the cooler valve body 27a opens from the fully closed position in the opening direction is eliminated. For this reason, by using the bypass valve 21 using the three-way valve body 27 in the EGR cooler unit 2, that is, by using it in the EGR cooler and the bypass passage 4, the linear controllability of the EGR gas temperature is improved. be able to.

<Fourth embodiment>
Next, a fourth embodiment embodying the EGR cooler bypass valve of the present invention will be described in detail with reference to the drawings.

  This embodiment differs from the third embodiment in terms of the gas flow rate adjustment structure of the present invention. FIG. 8 shows a bypass valve 21 of this embodiment in a cross-sectional view similar to FIG. As shown in FIG. 8, this embodiment differs from the third embodiment in that a cooling water passage 31 through which engine cooling water flows is formed in the center of the partition wall 24. In this embodiment, since the partition wall 24 is formed thicker than the partition wall 84 of the conventional example, the cooling water passage 31 can be formed in the partition wall 24 accordingly.

  Therefore, in this embodiment, the following actions and effects can be obtained in addition to the actions and effects similar to those of the third embodiment. That is, by flowing the engine coolant through the coolant passage 31, the area around the three-way valve body 27 is cooled. As a result, the heat resistance reliability of the bypass valve 21 can be improved.

<Fifth Embodiment>
Next, a fifth embodiment embodying the EGR cooler bypass valve of the present invention will be described in detail with reference to the drawings.

  This embodiment is different from the third and fourth embodiments in terms of the gas flow rate adjusting structure of the present invention. FIG. 9 shows a bypass valve 21 of this embodiment in a cross-sectional view similar to FIG. As shown in FIG. 9, in this embodiment, the partition wall 84 and the three-way valve type valve element 87 have the same configuration (shape and size) as in the conventional example, and the diameter-expanded curved surfaces 25a and 26a are formed in the flow passages 25 and 26, respectively. Straight portions 25b and 26b that are continuous and have a constant inner diameter are provided. Each straight part 25b, 26b is arrange | positioned corresponding to the range which the cooler valve body 87a and the bypass valve body 87b each rock | fluctuate. As a result, the change from the first opening area SA to the third opening area SC when the cooler valve element 87a is slightly rotated from the fully open position to the closing direction as shown by a two-dot chain line in FIG. It is almost equivalent to that of other opening ranges. Alternatively, the change in the opening area from the intermediate opening to the fully opened position is made uniform between the fully opened position and the fully closed position by reducing the change in the opening area at the intermediate opening. Thereby, the gas flow rate change in the range near the fully open position of the cooler valve element 87a becomes substantially the same as the gas flow rate change in the other opening ranges. The same applies to the bypass valve element 87b and the bypass flow path 26. This configuration corresponds to an example of the gas flow rate adjustment structure of the present invention.

  With this structure, the cooler flow in the vicinity of the fully open position of the cooler valve body 87a when the cooler valve body 87a rotates in the closing direction from the fully open position and the bypass valve body 87b rotates in the opening direction from the fully closed position. The large and small imbalance between the change in the gas flow rate in the passage 25 and the change in the gas flow rate in the bypass passage 26 in the vicinity of the fully closed position of the bypass valve element 87b is eliminated. In addition, when the bypass valve element 87b rotates from the fully open position to the closing direction and the cooler valve element 87a rotates from the fully closed position to the opening direction, the bypass flow path in the vicinity of the fully open position of the bypass valve element 87b. Thus, a large and small imbalance between the change in the gas flow rate 26 and the change in the gas flow rate in the cooler passage 25 in the vicinity of the fully closed position of the cooler valve element 87a is eliminated.

  Therefore, this embodiment can obtain the same operation and effect as the third embodiment.

  Note that the present invention is not limited to the above-described embodiments, and a part of the configuration can be changed as appropriate without departing from the spirit of the invention.

(1) In each of the above embodiments, the EGR cooler (cooler passage 3 and heat exchanger 9) and bypass passage 4 are integrally provided in the cooler casing 5, but the EGR cooler and bypass passage may be provided separately.
(2) In each of the above embodiments, the EGR cooler bypass valve of the present invention is used as an EGR cooler constituting an exhaust system of the engine in order to control the EGR gas temperature, but the EGR cooler bypass valve of the present invention is It can also be applied to the intake system to control the temperature.

  The present invention can be used for an EGR device provided with an EGR cooler in an engine system.

DESCRIPTION OF SYMBOLS 1 Bypass valve 3 Cooler passage 4 Bypass passage 9 Heat exchanger 11 Valve casing 12 Cooler passage 13 Bypass passage 14 Partition 15 Cooler valve body 16 Bypass valve body 17 Valve shaft 20 Convex part 21 Bypass valve 22 Valve casing 24 Partition 24a Cooler Slope 24b Bypass slope 25 Cooler channel 25b Straight portion 26 Bypass channel 26b Straight portion 27 Three-way valve body 27a Cooler valve body 27b Bypass valve body 27c Connecting portion 28 Valve shaft L1 Central axis

Claims (6)

An EGR cooler bypass valve that is used together with an EGR cooler for cooling EGR gas and simultaneously adjusts the flow rate of EGR gas passing through the EGR cooler and the flow rate of EGR gas passing through a bypass passage bypassing the EGR cooler. There,
A casing including a cooler flow path through which the EGR gas that has passed through the EGR cooler flows, and a bypass flow path through which the EGR gas that has passed through the bypass passage flows, wherein the cooler flow path and the bypass flow path are partitioned by a partition wall; ,
A plate-like cooler valve body for opening and closing the cooler flow path;
A bypass valve body having a plate shape for opening and closing the bypass flow path;
A valve shaft for integrally rotating the cooler valve body and the bypass valve body;
By rotating the valve shaft in one direction, the cooler valve body rotates in the opening direction and the bypass valve body rotates in the closing direction, and by rotating the valve shaft in the reverse direction, the cooler valve body rotates. The bypass valve body is configured to rotate in the opening direction while the valve body rotates in the closing direction,
The cooler valve body is opened and closed between a fully open position where the gas flow rate of the cooler flow path is maximized and a fully closed position where the gas flow rate of the cooler flow path is zero,
The bypass valve body is configured to open and close between a fully open position where the gas flow rate of the bypass flow path is maximized and a fully closed position where the gas flow rate of the bypass flow path is zero. In
When the cooler valve body rotates in the closing direction from the fully opened position and the bypass valve body rotates in the opening direction from the fully closed position, the cooler valve body in the vicinity of the fully opened position The imbalance between the change in the gas flow rate in the cooler flow path and the change in the gas flow rate in the bypass flow path in the vicinity of the fully closed position of the bypass valve element is eliminated, and the bypass valve element is closed from the fully open position to the closed position. Gas flow rate change in the bypass passage and the cooler valve in the vicinity of the fully open position of the bypass valve body when the cooler valve body rotates in the direction and the cooler valve body rotates in the opening direction. An EGR cooler comprising a gas flow rate adjusting structure for eliminating an imbalance between changes in the gas flow rate of the cooler flow path in the vicinity of the fully closed position of the body Ipasubarubu.   In the gas flow rate adjusting structure, the fully opened position of the cooler valve body and the fully opened position of the bypass valve body are respectively set in a predetermined direction from the state parallel to the central axis of the casing in the EGR gas flow direction to the closing direction. The EGR cooler bypass valve according to claim 1, wherein the EGR cooler bypass valve is moved by an angle of.   3. The EGR according to claim 2, wherein the cooler valve body and the bypass valve body have a rotation angle between the fully closed position and the fully open position set to an angle of 50 ° to 70 °. Cooler bypass valve.   The EGR cooler bypass valve according to any one of claims 1 to 3, wherein the cooler valve body and the bypass valve body are in contact with the casing at least in the fully closed position. The cooler valve body and the bypass valve body are butterfly type valve bodies, and the valve shaft is disposed through the cooler flow path, the partition wall, and the bypass flow path,
2. The cooler valve body is fixed to the valve shaft in the cooler flow path, and the bypass valve body is fixed to the valve shaft in the bypass flow path. The EGR cooler bypass valve in any one of thru | or 4. The cooler valve body and the bypass valve body are integrally formed via a connecting portion to constitute a three-way valve body,
The valve shaft is arranged in parallel with one end face of the partition wall in the EGR gas flow direction, and the three-way valve body is fixed to the valve shaft at the connecting portion,
The cooler valve body is disposed so as to be swingable in the cooler flow path about the valve shaft, and the bypass valve body is disposed to be swingable in the bypass flow path about the valve shaft. The EGR cooler bypass valve according to any one of claims 1 to 4, wherein the EGR cooler bypass valve is provided.

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