JP6695816B2 - Flow path switching valve - Google Patents

Description

  The present invention switches a flow path of a fluid from one direction to one of two branched flow paths, or switches one of the flow paths of fluid from two directions to a flow path of one direction. Regarding the valve.

  For example, in a vehicle equipped with an internal combustion engine, some of the exhaust gas in the exhaust path is returned to the intake path to lower the combustion temperature and reduce the amount of nitrogen oxides in the exhaust gas. A circulation system (hereinafter referred to as an EGR device) is installed. An EGR cooler that lowers the temperature of the exhaust gas in the EGR path is provided in the EGR path that returns a part of the exhaust gas from the exhaust path to the intake path in order to increase the effect of lowering the combustion temperature. There are cases.

  When the EGR cooler is provided, for example, a coolant for cooling is supplied to the EGR cooler, and the exhaust gas that passes through the EGR cooler is cooled by the coolant. However, for example, at the time of starting the internal combustion engine in a low temperature environment, the temperature of the cylinder or the like forming the combustion chamber with respect to the internal combustion engine after warming up is low, and the fuel in the combustion chamber may be difficult to vaporize. When the fuel in the combustion chamber is difficult to vaporize, combustion is likely to become unstable due to occurrence of misfire and the startability is deteriorated. Therefore, in such a case, it is preferable not to cool the exhaust gas in the EGR passage with the EGR cooler. After the internal combustion engine is warmed up, the temperature of the combustion chamber becomes sufficiently high, the fuel in the combustion chamber is appropriately vaporized, and the combustion becomes stable. Therefore, it is preferable to cool the exhaust gas in the EGR path by the EGR cooler. Therefore, various flow path switching valves have been proposed that switch the EGR path to a path that passes through the EGR cooler and a path that bypasses the EGR cooler as necessary.

  For example, in Patent Document 1, an inlet port, a first outlet port, and a second outlet port are formed in a valve passage in a housing, and a flow path switching that switches the first outlet port and the second outlet port to communicate with the inlet port. A valve is disclosed. A partition wall is formed between the first outlet port and the second outlet port, and the valve shaft is rotatably supported at a position near the partition wall. Then, a valve body in which two valve blades are arranged in an L shape (a first valve blade disposed on the first outlet port side and a second valve blade disposed on the second outlet port side) And a valve body in which the parts are arranged in an L shape are attached to the valve shaft. When the valve body is rotated so that the inlet port communicates with the first outlet port, the first valve blade portion on the first outlet port side is in close contact with the wall surface of the partition wall on the first outlet port side. 1 Open the side of the outlet port. At this time, the second valve blade portion on the side of the second outlet port closes the side of the second outlet port so as to block the communication with the inlet port.

JP 2004-190693 A

  The exhaust gas of an internal combustion engine contains incomplete combustion products of fuel and engine oil, and the incomplete combustion products are generated at various points in the EGR path that returns a part of the exhaust gas to the intake path. In some cases, a so-called deposit may be deposited. Therefore, when the flow path switching valve described in Patent Document 1 is used in the EGR path, incomplete combustion products may be deposited at various locations inside the flow path switching valve.

  In the flow path switching valve described in Patent Document 1, for example, when the inlet port is communicated with the first outlet port, the first valve blade portion on the first outlet port side is closely attached to the wall surface on the first outlet port side of the partition wall. Thus, the fluid from the first outlet port is prevented from leaking to the second outlet port. At this time, the valve vane portion first port side plane that is the partition wall side surface of the first valve blade portion on the first outlet port side, and the partition wall first port side that is the wall surface of the partition wall on the first outlet port side. The plane and the plane are in close contact with each other. However, if incomplete combustion products are accumulated on the plane of the valve-blade first port side or the plane of the partition wall first port to cause irregularities, the sealing performance may be deteriorated and it may not be possible to adhere them. .. In this case, the fluid from the first outlet port may leak to the second outlet port, which is not preferable.

  That is, in the case where the planar valve blade portion and the planar partition surface are brought into close contact with each other, the pressure per unit area becomes small because the flat surfaces are brought into close contact with each other. Therefore, there is a possibility that the pressure for crushing the deposit of the incomplete combustion product is insufficient and the unevenness due to the accumulation of the incomplete combustion product cannot be made flat, and the sealing property may be deteriorated.

  The present invention has been devised in view of such a point, and in a flow path switching valve in which the second flow path and the third flow path are switched to communicate with the first flow path by a valve body, An object of the present invention is to provide a flow path switching valve capable of further improving the sealing property between the flow path and the third flow path.

In order to solve the above problems, a first aspect of the present invention relates to a housing in which a first flow path, a second flow path, and a third flow path are formed, and a second flow path and a third flow path with respect to the first flow path. In a flow path switching valve having a valve body that switches and communicates a path and a valve shaft that rotatably supports the valve body, a first opening portion that communicates with a first flow path in a housing, A second opening communicating with the flow passage and a third opening communicating with the third flow passage are provided, and the first flow passage, the second flow passage, and the third flow passage are provided in the housing. A communication region that is a region connected to each other is provided, the first opening to the communication region is formed as a first flow path, and the second opening to the communication region is formed as a second flow path. The third flow path is formed from the three openings to the communication area, and the communication area includes the second flow path communication area which is a connecting portion between the first flow path and the second flow path, the first flow path and the third flow path. A third flow passage communicating region that is a connecting portion with the flow passage, and the second flow passage and the third flow passage reach the communication region from between the second opening and the third opening. The partition wall is thus partitioned, the second flow path side of the partition wall has a planar second flow path side partition surface, and the partition wall has a planar second partition surface. The 3-passage-side partition wall surface is formed, and the valve body has two flat plate-shaped valve blade portions, and the second passage communication region is opened and the third passage communication region is opened by the rotation of the valve shaft. To a second flow path communication position for closing the third flow path communication region and a third flow path communication position for opening the third flow path communication region and closing the second flow path communication region. A second flow passage side valve blade surface having a planar second flow passage side valve blade surface that approaches the second flow passage side partition surface so as to face the second flow passage side partition surface when the valve body is rotated to the second flow passage communicating position; Holds the second flow passage side valve blade surface and the second flow passage side partition wall surface that have come close to each other when the valve body is rotated to the second flow passage communicating position, and keeps the second flow passage from the second flow passage. The second flow path side convex portion that comes into contact with the second flow path side partition wall surface so as to close the gap reaching the three flow paths is provided so as to be continuous along the second flow path side valve blade surface, and the other The valve vane portion has a planar third flow passage side valve vane surface that approaches so as to face the third flow passage side partition wall surface when the valve body is rotated to the third flow passage communicating position. The flow path side valve blade surface holds the third flow path side valve blade surface and the third flow path side partition surface which are close to each other when the valve body is rotated to the third flow path communicating position, in a non-contact state. The third flow path side convex portion that contacts the third flow path side partition wall surface so as to close the gap from the third flow path to the second flow path is continuous along the third flow path side valve blade surface. It is a flow path switching valve provided so as to perform.

  Next, a second aspect of the present invention is the flow path switching valve according to the first aspect of the present invention, wherein the valve body is L-shaped in one valve blade portion and the other valve blade portion when viewed in the valve axis direction. It is a flow path switching valve formed in.

  Next, a third invention is a flow path switching valve according to the first invention or the second invention, wherein the second flow path side convex portion and the third flow path side convex portion provided on the valve body are provided. The part is a flow path switching valve that is formed by a separate member that is a member different from the valve body.

  Next, a fourth invention is a flow path switching valve according to any one of the first to third inventions, wherein one end is connected to an exhaust pipe of an internal combustion engine and the other end is a first main flow path. An exhaust gas introduction path connected to the first main flow path of a branching section that branches into two flow paths, a branch section, two flow paths, and an exhaust gas that is provided in one of the two flow paths and flows in the flow path. An EGR cooler that cools the gas, a merging portion that merges the two flow passages into a second main flow passage, one end is connected to the second main flow passage of the merging portion, and the other end is connected to the intake pipe of the internal combustion engine. And an intake air intake passage, the flow passage switching valve is used in a branching portion or a merging portion.

  According to the first aspect of the present invention, when the valve body is set to the second flow path communicating position when switching the valve body, the first flow path and the second flow path communicate with each other and the third flow path is closed. At this time, the second flow path side valve vane surface and the second flow path side partition wall surface are in a non-contact state, and the second flow path side convex portion provided on the second flow path side valve blade surface is the second flow path side partition wall surface. To contact. Therefore, compared with the case where the second flow path side valve vane surface and the second flow path side partition wall surface are brought into contact with each other, the contact area can be made extremely small, so that the pressure per unit area at the contact portion is very small. Can be large. Thereby, the unevenness of the deposit of the incomplete combustion product on the partition wall surface is crushed, and the sealing property between the second flow path and the third flow path can be improved. Even when the valve body is in the third flow passage communicating position, similarly, the third flow passage side valve blade surface and the third flow passage side partition wall surface are not in contact with each other, and are provided on the third flow passage side valve blade surface. The third flow path-side convex portion is in contact with the third flow path-side partition wall surface. Therefore, the pressure per unit area in the contact portion can be made very large, so that the sealing property between the second flow path and the third flow path can be improved.

  According to the second aspect of the present invention, by making the two valve vanes L-shaped, one valve vane opens the second channel communication region and the other valve vane opens the third channel communication region. And closing the second flow passage communication region with one valve blade portion and opening the third flow passage communication region with the other valve blade portion can be easily realized. it can.

  According to the third invention, the second flow path side convex portion and the third flow path side convex portion are formed as separate members, so that the shapes and materials of the second flow path side convex portion and the third flow path side convex portion are formed. And the degree of freedom of the mounting positions of the second flow passage side convex portion and the third flow passage side convex portion on the valve body.

  According to the fourth invention, in an EGR device having an EGR cooler in a diesel engine or the like, a path passing through the EGR cooler and a path bypassing the EGR cooler can be switched as necessary, and the second It is possible to realize a good EGR device in which the amount of exhaust gas leakage between the flow passage and the third flow passage is small.

It is a figure explaining the schematic structure of the internal-combustion engine which applied the flow-path switching valve of the present invention to the EGR path. It is a perspective view explaining the external appearance of the flow path switching valve in the first embodiment. FIG. 3 is a bottom view of the flow path switching valve shown in FIG. 2. It is a front view of the flow-path switching valve shown in FIG. FIG. 5 is a sectional view taken along line VV of FIG. 2. FIG. 3 is a perspective view (perspective view) showing the arrangement of the first flow passage, the second flow passage, the third flow passage, the partition wall, and the valve body provided inside the flow passage switching valve in an exaggerated manner in the vertical direction of the housing. .. It is a perspective view explaining the external appearance of the valve body in the first embodiment. It is a VIII-VIII sectional view of FIG. It is a cross-sectional perspective view explaining the example (the 1) of the formation method of the 2nd flow path side convex part and the 3rd flow path side convex part which were provided in the valve blade part. It is a cross-sectional perspective view explaining the example (the 2) of the formation method of the 2nd flow path side convex part and the 3rd flow path side convex part which were provided in the valve blade part. It is a cross-sectional perspective view explaining the example (the 3) of the formation method of the 2nd flow path side convex part and the 3rd flow path side convex part which were provided in the valve blade part. It is a perspective view explaining the external appearance of the valve body in a 2nd embodiment. FIG. 13 is a cross-sectional view of the flow path switching valve according to the second embodiment in which the valve body is the valve body shown in FIG. 12 as opposed to the sectional view shown in FIG. 5. It is a XIV-XIV sectional view of FIG.

● [Schematic overall structure of internal combustion engine fuel supply system (Fig. 1)]
Hereinafter, the flow path switching valve of the present invention will be described in detail with reference to the drawings. First, the schematic configuration of an internal combustion engine (the example of FIG. 1 is a diesel engine) in which the “flow path switching valve 10” of the present invention is applied to the EGR path 130 will be described with reference to FIG.

  FIG. 1 shows an example of a schematic configuration of a diesel engine (internal combustion engine) mounted on an automobile or the like. As shown in FIG. 1, this diesel engine includes an engine 100, exhaust pipes 110a, 110b, 110c, intake pipes 120a, 120b, 120c, a turbocharger 150, an EGR path 130, and the like. The fuel supplied from the fuel tank is injected into each cylinder 114 via the common rail 112 and the injector 113. It should be noted that various detecting means for detecting the operating state of the internal combustion engine and a control device for controlling each actuator such as the injector 113 based on a detection signal from the detecting means are omitted.

  The intake path is a passage for supplying the intake air (intake air) to the engine 100, and includes an intake pipe 120a, an intake pipe 120b, and an intake pipe 120c. The intake air that has flowed into the intake pipe 120a before combustion is pumped from the intake pipe 120a to the intake pipe 120b via the turbo compressor 152 by the turbo compressor 152 that constitutes the turbocharger 150. The turbo compressor 152 is connected to a turbo turbine 151 driven by exhaust gas. The intake air flowing through the intake pipe 120b is mixed with the exhaust gas that has passed through the EGR path 130 described later and flows into the intake pipe 120c. The gas in which the intake air and the exhaust gas are mixed is sucked into each cylinder of the engine 100. The intake pipe 120a is provided with flow rate detection means 154 (flow rate sensor or the like) for detecting the flow rate of the intake air.

  The exhaust path is a passage through which exhaust gas discharged from the engine 100 flows, and is configured by an exhaust pipe 110a, an exhaust pipe 110b, and an exhaust pipe 110c. Specifically, the exhaust gas after combustion is discharged from each cylinder of the engine 100 to the exhaust pipe 110a, and flows to the turbo turbine 151 side via the exhaust pipe 110b. The exhaust gas that has reached the turbo turbine 151, after rotating the turbo turbine 151, is guided to the exhaust gas purification device 153 through the exhaust pipe 110c and is purified. A part of the exhaust gas discharged to the exhaust pipe 110a flows into the EGR exhaust introduction passage 111, and passes through one of the EGR cooler passage 131 or the bypass passage 134 and the EGR intake introduction passage 121 to the intake pipe 120c. Will be led.

  The EGR passage 130 is formed by the EGR exhaust introduction passage 111, the EGR cooler passage 131, the bypass passage 134, and the EGR intake introduction passage 121. The upstream side of the EGR exhaust introduction path 111 is connected to the exhaust pipe 110a. The downstream side of the EGR exhaust introduction path 111 is connected to the upstream sides of the EGR cooler passage 131 and the bypass passage 134, and the passage switching valve 10 is provided at the connecting portion. An EGR cooler 135 is provided in the EGR cooler passage 131. The downstream sides of the EGR cooler passage 131 and the bypass passage 134 are joined at a joining portion 133 and connected to the upstream side of the EGR intake air introduction passage 121. The EGR intake air intake passage 121 is provided with an EGR valve 140 capable of adjusting the flow rate of exhaust gas flowing through the EGR intake air intake passage 121. The downstream side of the EGR intake air intake passage 121 is connected to the intake pipe 120c. Hereinafter, the flow path switching valve 10 will be described in detail.

● [Flow passage switching valve 10 in the first embodiment (Figs. 2 to 11)]
Next, the detailed configuration and operation of the flow path switching valve 10 in the first embodiment will be described with reference to FIGS. 2 to 11. For convenience of description, the X-axis, Y-axis, and Z-axis directions shown in FIG. 2 are set and described. Further, a surface of the housing on which the actuator 12 is provided is referred to as a “front surface”. The X axis, the Y axis, and the Z axis in the drawing are orthogonal to each other, and the direction from the rear surface to the front surface of the housing is the X axis direction, the direction from the left side surface to the right side surface is the Y axis direction, and the lower surface to the upper surface. The direction is the Z-axis direction. For each direction, the Z-axis direction is "up", the direction opposite to the Z-axis direction is "down", the X-axis direction is "front", the side opposite to the X-axis direction is "rear", and the Y-axis direction is "right". , And the direction opposite to the Y-axis direction will be described as “left”.

● [Appearance of flow path switching valve 10 (Figs. 2-4)]
First, the external appearance of the flow path switching valve 10 according to the first embodiment will be described with reference to FIGS. 2 to 4. 2 is a perspective view showing the external appearance of the flow path switching valve 10, FIG. 3 is a bottom view of the flow path switching valve 10, and FIG. 4 is a front view of the flow path switching valve 10. A first opening 16 is provided on the upper surface of the housing 11 at the center of the surface, and the first opening 16 is connected to the downstream side of the EGR exhaust gas introduction path 111 (see FIG. 1). A through hole extending in the front-rear direction is provided on the front side surface of the housing 11, and the valve shaft 15 is rotatably inserted in the through hole. The valve shaft 15 is inserted into a valve bearing hole 34 (see FIG. 7) provided in the valve body 30 and rotates integrally with the valve body 30 (see FIG. 4). The front end of the housing 11 of the valve shaft 15 projects from the front surface of the housing 11 and is connected to the actuator 12 (for example, a diaphragm) via the link members 14 and 14a and the rod 13. The actuator 12 is fixed to a stay 12 a provided in the housing 11. The actuator 12 reciprocates the rod 13 in the longitudinal direction to rotate the valve shaft 15 via the link members 14 and 14a (see FIG. 4).

  As shown in FIG. 3, the lower surface of the housing 11 is provided with a second opening 17 and a third opening 18. For example, the second opening 17 has an EGR cooler passage 131 (see FIG. 1). The upstream side is connected, and the upstream side of the bypass passage 134 (see FIG. 1) is connected to the third opening 18. Further, as shown in FIG. 3, a partition 19 is provided between the second opening 17 and the third opening 18 so as to be parallel to the valve shaft 15, and the partition 19 allows the second opening to be formed. 17 and the third opening 18 are partitioned.

● [Internal structure of flow path switching valve 10 (Figs. 5-11)]
First, the first flow path 20, the second flow path 21, and the third flow path 22 will be described with reference to FIG. As shown in FIG. 5, the partition wall 19 extends from between the first opening 16 and the third opening 18 to reach the communication region 25 (to a position close to the valve shaft 15). Further, as shown in FIG. 5, the housing 11 has a first flow path 20 communicating with the first opening 16, a second flow path 21 communicating with the second opening 17, and a third opening 18. A third flow path 22 that communicates is provided. The communication area 25 is an area in which the first flow path 20, the second flow path 21, and the third flow path 22 are connected, and is a connection portion between the first flow path 20 and the second flow path 21. It has two flow passage communication regions 23 and a third flow passage communication region 24 which is a connecting portion between the first flow passage 20 and the third flow passage 22. The flow path from the first opening 16 to the communication area 25 is the first flow path 20, the flow path from the second opening 17 to the communication area 25 is the second flow path 21, and the third opening 18 is The flow path up to the communication area 25 is the third flow path 22. Further, as shown in FIG. 6, at the boundary between the first flow passage 20 and the second flow passage 21, the second flow passage that is a surface that the valve blade portion 31 a contacts when closing the second flow passage 21. The valve blade contact surface 26a is provided so as to be continuous along the inner wall surface. Similarly, at the boundary between the first flow passage 20 and the third flow passage 22, a third flow passage valve blade contact surface that is a surface that the valve blade portion 31 b contacts when closing the third flow passage 22. 26b is provided so as to be continuous along the inner wall surface.

  Next, the structure of the partition 19 will be described. A partition wall 19 is provided between the second opening 17 and the third opening 18 of the housing 11. The partition wall 19 is provided up to the vicinity of the valve shaft 15 as shown in FIG. That is, the second flow path and the third flow path are partitioned by the partition wall 19 provided between the second opening and the third opening to reach the communication region 25. A planar second flow channel side partition wall surface 19a is formed on the partition wall 19 on the second flow channel 21 side, and a planar third flow channel side partition wall surface 19b is formed on the third flow channel 22 side on the partition wall 19. Has been done.

  Next, the structure of the valve body 30 will be described with reference to FIG. 7. As shown in FIG. 7, the valve body 30 has two flat plate-shaped valve blade portions 31 a and 31 b, and the valve blade portion 31 a and the valve blade portion 31 b sandwich the valve bearing hole 34 and have an angle θ. It is formed to have an L shape. For example, the angle θ is set to 90 degrees. As shown in FIG. 7, the contour shape of the outer periphery of the valve blade portion 31b has side portions S4 and S5 that are linearly parallel, and a top portion S6 having an arc shape. The side portions S4 and S5 and the top portion S6 are shaped so as to overlap the third flow passage valve blade contact surface 26b shown in FIG. Similarly, the contour shape of the outer periphery of the valve blade portion 31a has side portions S1 and S2 that are linearly parallel, and a top portion S3 having an arc shape. The side portions S1 and S2 and the top portion S3 are shaped so as to overlap the second flow passage valve blade contact surface 26a shown in FIG.

  As shown in FIG. 7, the plane of the valve vane portion 31a closer to the valve vane portion 31b is defined as the second flow path side valve vane surface 33a, and the plane of the valve vane portion 31b closer to the valve vane portion 31a is defined as the third The flow path side valve blade surface 33b is used. The third flow passage side valve blade surface 33b is provided with a third flow passage side convex portion 32b that extends from the side portion S4 that is linear to the side portion S5. The third flow passage side convex portion 32b is provided so that the height protruding from the third flow passage side valve blade surface 33b is constant and is continuous from the side portion S4 to the side portion S5. In the example shown in FIG. 7, the path from the side portion S4 to the side portion S5 in the third flow path side convex portion 32b extends slightly inward from the side portion S4 and then slightly inward from the edge portion of the top portion S6. Although the route is to reach the side part S5 after reaching the vicinity of the side part S5, any route may be used as long as it is a route from the side part S4 to the side part S5. Similarly, the second flow passage side valve blade surface 33a is provided with a second flow passage side convex portion 32a extending from the linear side portion S1 to the side portion S2. The route from the side portion S1 to the side portion S2 in the second flow path side convex portion 32a may be any route as long as it is a route from the side portion S1 to the side portion S2.

  Next, an example of a method of forming the third flow path side convex portion 32b will be described with reference to FIGS. Since the same applies to the second flow path side convex portion 32a, the description of the second flow path side convex portion 32a will be omitted. The example shown in FIG. 9 shows an example in which a wire 35 having a constant diameter (the height 38 from the third flow path side valve blade surface 33b is constant) is welded to the third flow path side valve blade surface 33b. An example in which the third flow path side convex portion 32b having a constant height 38 is formed by the wire material 35 fixed by the beads 36 is shown. It is preferable to use the wire material 35 having an arcuate cross section because the wire material 35 is brought into a line contact state when contacting the third flow path side partition wall surface 19b and the contact area can be further reduced. In the example shown in FIG. 10, the weld bead 36 is formed (only the weld bead is formed) so that the height 38 from the third flow path side valve blade surface 33b is constant, so that the height 38 is constant. An example in which the three-channel-side convex portion 32b is formed is shown. In the example shown in FIG. 11, the third flow passage side convex portion 32b having a constant height 38 is formed by press molding so that the height 38 from the third flow passage side valve blade surface 33b becomes constant. The example integrally formed with the roadside valve blade surface 33b is shown. As described above, there are various methods for forming the second flow path side convex portion 32a and the third flow path side convex portion 32b.

● [Operation of flow path switching valve 10]
The operation of the actuator 12 will be described with reference to FIG. By having the above-described configuration, the actuator 12 operates to contract the rod 13 at the time of starting in a low temperature environment, and extends to extend the rod 13 at the time of starting in a low temperature environment, for example. . When the actuator 12 extends the rod 13 (moves the rod 13 downward in FIG. 4), the link member 14 a (see FIG. 2) rotates the valve shaft 15 via the link member 14 (valve shaft in FIG. 4). 15 is rotated counterclockwise), and the valve body 30 is rotated to the second flow path communicating position 23a shown by the solid line in FIG. Thereby, the valve body 30 opens the second flow passage 21 and closes the third flow passage 22. When the actuator 12 contracts the rod 13 (moves the rod 13 upward in FIG. 4), the link member 14a (see FIG. 2) rotates the valve shaft 15 via the link member 14 (valve in FIG. 4). The shaft 15 is rotated clockwise), and the valve body 30 is rotated to the third flow path communicating position 24a indicated by the chain double-dashed line in FIG. As a result, the valve body 30 opens the third flow path 22 and closes the second flow path 21.

  When the valve body 30 is rotated to the second flow path communicating position 23a shown by the solid line in FIG. 5, the second flow path side convex portion provided on the second flow path side valve blade surface 33a of the valve blade portion 31a. 32a holds the second flow path side valve blade surface 33a (opposing and approaching) and the second flow path side partition wall surface 19a in a non-contact state. At the same time, the second flow path side convex portion 32a contacts the second flow path side partition wall surface 19a so as to close the gap from the second flow path 21 to the third flow path 22, as shown in FIGS. 5 and 6. To do. As described above, the second flow passage-side convex portion 32a is a continuous shape in which the height from the side portion S1 of the second flow passage-side valve blade surface 33a to the side portion S2 is constant, and thus is shown in FIG. As described above, the gap from the second flow path 21 to the third flow path 22 can be appropriately closed. Then, the edge portion of the back surface of the third flow passage side valve blade surface 33b in the valve blade portion 31b is, as shown in FIG. 6, the third flow passage valve blade contact surface 26b formed on the inner wall of the third flow passage 22. And the third flow path 22 is closed.

  Thus, as shown in FIG. 5, when the valve body 30 is rotated to the second flow path communicating position 23a, the plane (second flow path side valve blade surface 33a) is flat (second flow path side partition wall surface 19a). ), The second channel-side convex portion 32a is pressure-bonded to the flat surface (the second channel-side partition wall surface 19a), so that the pressure per unit area at the pressure-bonded portion can be increased. As a result, the second flow path-side convex portion 32a crushes the unevenness of the deposit of the incomplete combustible material on the second flow path-side partition wall surface 19a and press-bonds it to the second flow path-side partition wall surface 19a. The sealing property with the third flow path 22 is further improved. In addition, since the deposits of incomplete combustion products are sticky, when the pressure-bonding area such as pressure-bonding between planes is large, the pressure-sensitive adhesive force between the planes is large and the valve body is separated from the partition wall. There is a possibility that it will be in a so-called fixed state without peeling. However, in the structure of the present application, since the flat surface and the convex portion are crimped, and the crimping area is very small, the adhesive force can be reduced and the valve body 30 can be prevented from sticking to the partition wall 19.

  When the valve body 30 is rotated to the third flow passage communicating position 24a shown by the chain double-dashed line in FIG. 5, the third flow passage-side protrusion provided on the third flow passage-side valve blade surface 33b of the valve blade portion 31b. The shaped portion 32b holds the third passage-side valve blade surface 33b (which is opposed and approaches) and the third passage-side partition wall surface 19b in a non-contact state. At the same time, the third flow path side convex portion 32b contacts the third flow path side partition wall surface 19b so as to close the gap from the third flow path 22 to the second flow path 21, as shown in FIGS. 5 and 6. To do. As described above, the third flow path side convex portion 32b is a continuous shape in which the height from the side portion S4 to the side portion S5 of the third flow passage side valve blade surface 33b is constant, and thus is shown in FIG. Thus, the gap from the third flow path 22 to the second flow path 21 can be appropriately closed. Then, as shown in FIG. 6, the edge portion of the back surface of the second flow passage side valve blade surface 33a in the valve blade portion 31a has a second flow passage valve blade contact surface 26a formed on the inner wall of the second flow passage 21. And the second flow path 21 is closed.

  Thus, as shown in FIG. 5, when the valve body 30 is rotated to the third flow passage communicating position 24a, the flat surface (third flow passage side valve blade surface 33b) is a flat surface (third flow passage side partition wall surface 19b). ), The third channel-side convex portion 32b is pressure-bonded to the flat surface (third channel-side partition wall surface 19b), so that the pressure per unit area at the pressure-bonded portion can be increased. As a result, the third flow path-side convex portion 32b crushes the unevenness of the deposit of incomplete combustibles on the third flow path-side partition wall surface 19b and press-bonds it to the third flow path-side partition wall surface 19b. The sealing property with the third flow path 22 is further improved. Further, since the flat surface and the convex portion are crimped and the crimping area is very small, the adhesive force can be reduced, and the valve body 30 can be prevented from sticking to the partition wall 19.

[Flow path switching valve 10z of the second embodiment (FIGS. 12 to 14)]
Next, the flow path switching valve 10z according to the second embodiment will be described with reference to FIGS. The flow path switching valve 10z of the second embodiment is different from the flow path switching valve 10 of the first embodiment shown in FIG. 5 in that the valve body 30 shown in FIG. 7 and the valve body 30z shown in FIG. The difference is that it has been changed to. Hereinafter, this difference will be mainly described.

  As shown in FIG. 12, the valve element 30z according to the second embodiment is different from the valve element 30 shown in FIG. 7 in that the valve blade portion 31a has a convex portion on the back surface of the second flow path side valve blade surface 33a. The difference is that the convex portion 32c is provided and the convex portion 32d is provided at the edge of the back surface of the third flow path side valve blade surface 33b of the valve blade portion 31b. Various methods can be used to form the convex portions 32c and the convex portions 32d, similar to the method for forming the second flow channel side convex portions 32a and the third flow channel side convex portions 32b shown in FIGS. 9 to 11. is there.

  The shape of the convex portion 32d will be described with reference to FIG. Since the same applies to the convex portion 32c, the description of the convex portion 32c will be omitted. Further, the forming method is the same as that of the second flow path side convex portion 32a and the third flow path side convex portion 32b, and thus the description thereof is omitted.

  As shown in FIG. 14, the convex portion 32d is continuously provided on the back surface of the third flow path side valve blade surface 33b so that the height 38z is constant. Further, as shown in FIG. 12, the convex portion 32d extends from the position of the side portion S4 close to the valve bearing hole 34 to the position of the side portion S5 close to the valve bearing hole 34 via the top portion S6. It is provided along the edge of the wing 31b. That is, when the valve body 30z is rotated to the second flow path communicating position 23a shown by the chain double-dashed line in FIG. 13, the convex portion 32d and the valve blade portion 31b and the third flow path valve blade in FIG. The contact surface 26b is provided at a position where the contact surface 26b contacts. As a result, when the valve body 30z is rotated to the second flow passage communicating position 23a (position of the valve body 30z shown by the two-dot chain line in FIG. 13), the third flow passage valve blade contact surface shown in FIG. The convex portion 32d contacts 26b, and the back surface of the third flow path side valve blade surface 33b is brought into a non-contact state.

  As shown in FIG. 12, the convex portion 32c extends from the position of the side portion S1 close to the valve bearing hole 34 to the position of the side portion S2 close to the valve bearing hole 34 via the top portion S3. It is provided along the edge of the portion 31a. That is, when the valve body 30z rotates to the third flow passage communicating position 24a shown by the solid line in FIG. 13, the convex portion 32c contacts the valve blade portion 31a and the second flow passage valve blade in FIG. The surface 26a and the surface 26a are provided in contact with each other. Accordingly, when the valve body 30z is rotated to the third flow passage communicating position 24a (the position of the valve body 30z shown by the solid line in FIG. 13), the second flow passage valve blade contact surface 26a in FIG. The back surface of the second flow path side valve blade surface 33a is brought into a non-contact state while the convex portion 32c is in contact.

  When the valve element 30z is rotated to the third flow passage communicating position 24a shown by the solid line in FIG. 13, the convex portion 32c provided on the back surface of the second flow passage side valve blade surface 33a in the valve blade portion 31a is , And the second flow path side valve blade contact surface 26a and the second flow path side valve blade contact surface 26a are held in a non-contact state. At the same time, as shown in FIG. 13, the convex portion 32c contacts the second flow passage side valve blade contact surface 26a so as to close the gap from the first flow passage 20 to the second flow passage 21. As described above, the convex portion 32c comes close to the valve bearing hole 34 via the top portion S3 from the position of the side portion S1 near the valve bearing hole 34 on the back surface of the second flow path side valve blade surface 33a. Since it has a continuous shape with a constant height reaching the position of the side portion S2, as shown in FIG. 6, it is possible to appropriately close the gap extending from the first flow path 20 to the second flow path 21.

  Thus, as shown in FIG. 13, when the valve body 30z is rotated to the third flow passage communicating position 24a, the flat surface (the back surface of the second flow passage side valve blade surface 33a) is a flat surface (the second flow passage side valve). Since the convex portion 32c is pressure-bonded to the flat surface (the second flow path side valve blade contact surface 26a) instead of being pressure-bonded to the blade contact surface 26a), the pressure per unit area at the pressure-bonded portion can be increased. As a result, the convex portion 32c crushes the unevenness of the deposits of the incomplete combustibles on the second flow passage side valve blade contact surface 26a and presses it to the second flow passage side valve blade contact surface 26a. The sealing property between 21 and the third flow path 22 is further improved. In addition, since the flat surface and the convex portion are crimped and the crimping area is very small, the adhesive force can be reduced, and the valve body 30z can be prevented from sticking to the second flow path side valve blade contact surface 26a. ..

  When the valve body 30z is rotated to the second flow path communicating position 23a indicated by the chain double-dashed line in FIG. 13, the convex portion provided on the back surface of the third flow path side valve blade surface 33b in the valve blade portion 31b. 32d holds the back surface of the third flow path side valve blade surface 33b (which is close to and opposed to) and the third flow path side valve blade contact surface 26b in a non-contact state. At the same time, the convex portion 32d contacts the third flow passage side valve blade contact surface 26b so as to close the gap extending from the first flow passage 20 to the second flow passage 21, as shown in FIG. As described above, the convex portion 32d comes close to the valve bearing hole 34 via the top portion S6 from the position of the side portion S4 near the valve bearing hole 34 on the back surface of the third flow path side valve blade surface 33b. Since the height reaching the position of the side portion S5 is a constant continuous shape, the gap from the first flow path 20 to the third flow path 22 can be appropriately closed.

Thus, as shown in FIG. 13, when the valve body 30z is rotated to the second flow path communicating position 23a, the plane (the back surface of the third flow path side valve blade surface 33b) is the plane (the third flow path side valve). Since the convex portion 32d is pressure-bonded to the flat surface (the third flow path side valve blade contact surface 26b) instead of being pressure-bonded to the blade contact surface 26b), the pressure per unit area at the pressure-bonded portion can be increased. As a result, the convex portion 32d crushes the unevenness of the deposit of the incomplete combustibles on the third flow passage side valve blade contact surface 26b and press-fits the third flow passage side valve blade contact surface 26b. The sealing property between 20 and the third flow path 22 is further improved. Further, since the flat surface and the convex portion are crimped and the crimping area is very small, the adhesive force can be reduced and the valve body 30z can be prevented from sticking to the third flow path side valve blade contact surface 26b. ..
● [Effect of this application]

  As described above, in the flow path switching valve 10 according to the first embodiment, for example, when the first flow path 20 is connected to the third flow path 22, the third flow path side valve vane surface 33b Since the 3rd flow path side convex part 32b contacts the 3rd flow path partition wall surface 19b, when a conventional plane (3rd flow path side valve blade surface 33b) and plane (3rd flow path partition surface 19b) contact. In comparison, the pressure per unit area can be increased, the unevenness of the deposit of incomplete combustibles on the third flow path partition wall surface 19b can be crushed, and the third flow path partition wall surface 19b can be pressed. As a result, in the flow passage switching valve 10, the sealing property between the second flow passage 21 and the third flow passage 22 can be improved.

  In addition, in the flow path switching valve 10z according to the second embodiment, for example, when the first flow path 20 is communicated with the third flow path 22, in addition to the effects described above, the second flow path valve blade surface 33a is provided. Since the convex portion 32c of 2 contacts the second flow passage valve blade contact surface 26a, the conventional plane (second flow passage valve blade surface 33a) and plane (second flow passage valve blade contact surface 26a) are formed. The pressure per unit area can be increased as compared with the case of contact, and the unevenness of the deposit of incomplete combustibles on the second flow passage valve blade contact surface 26a is crushed, and the second flow passage valve blade contact surface is formed. It can be crimped by 26a. As a result, in the flow path switching valve 10z, the sealing property between the flow paths that do not communicate with the first flow path 20 can be improved.

  The flow path switching valve of the present application not only improves the sealing property between the second flow path and the third flow path when the first flow path is switched to the second flow path or the third flow path for communication. The sealing property between the second flow path and the third flow path can be further improved.

  The flow path switching valve of the present invention is not limited to the configuration, structure, etc. described in the present embodiment, and various changes, additions and deletions can be made without changing the gist of the present invention. In particular, the shape of the valve body 30 is not limited to the shape shown in the present embodiment, and when switching the first flow path to the second flow path or the third flow path, the flow path on the communicating side is opened and communication is performed. Any shape may be used as long as it closes the flow path on the non-use side.

  The flow path switching valve described in the present embodiment is not limited to the EGR device for an internal combustion engine shown in FIG. 1, and can be applied as a flow path switching valve for a fluid flow path of an internal combustion engine. Further, although the example applied to the branch portion according to FIG. 1 has been described, the flow path switching valve may be applied to the joining portion 133 (see FIG. 1) instead of the branch portion.

10, 10z flow path switching valve 11 housing 12 actuator 12a stay 13 rod 14, 14a link member 15 valve shaft 16 first opening 17 second opening 18 third opening 19 partition wall 19a second flow path side partition surface 19b third Flow path side partition wall surface 20 First flow path 21 Second flow path 22 Third flow path 23 Second flow path communication area 23a Second flow path communication position 24 Third flow path communication area 24a Third flow path communication position 25 Communication area 26a 2nd flow path valve wing contact surface 26b 3rd flow path valve wing contact surface 30, 30z Valve body 31a, 31b Valve wing part 32a 2nd flow path side convex part 32b 3rd flow path side convex part 32c, 32d Convex portion 33a Second flow path side valve blade surface 33b Third flow path side valve blade surface 34 Valve bearing hole 35 Wire rod 36 Weld bead 38, 38z Height 100 Engine (internal combustion engine)
110a, 110b, 110c Exhaust pipe 111 EGR exhaust introduction passage 112 Common rail 113 Injector 114 Cylinder 120a, 120b, 120c Intake pipe 121 EGR intake introduction passage 130 EGR passage 131 EGR cooler passage 133 Confluence part 134 Bypass passage 135 EGR cooler 140 EGR valve 150 Turbocharger 151 Turbo turbine 152 Turbo compressor 153 Exhaust gas purifier 154 Flow rate detection means S1, S2, S4, S5 Side parts S3, S6 Top part

Claims (4)

A housing in which a first flow path, a second flow path and a third flow path are formed,
A valve body that switches the second flow path and the third flow path to communicate with the first flow path;
A valve shaft rotatably supporting the valve body,
In the flow path switching valve having
The housing is provided with a first opening communicating with the first flow path, a second opening communicating with the second flow path, and a third opening communicating with the third flow path. And
A communication area, which is an area in which the first flow path, the second flow path, and the third flow path are connected to each other, is provided in the housing, and the area from the first opening to the communication area is provided. Is formed as the first flow path, the second opening to the communication area is formed as the second flow path, and the third opening to the communication area is formed as the third flow path,
The communication area is a second flow path communication area that is a connection portion between the first flow path and the second flow path, and a third flow path that is a connection portion between the first flow path and the third flow path. And a road communication area,
The second flow path and the third flow path are partitioned by a partition wall provided so as to reach the communication region from between the second opening and the third opening,
A flat second flow path side partition surface is formed on the partition wall on the side of the second flow path, and a flat third flow path side partition surface is formed on the side of the third flow path on the partition wall. Cage,
The valve body has two flat plate-shaped valve wings, and a second flow passage that opens the second flow passage communication region and closes the third flow passage communication region by rotation of the valve shaft. Rotated to a communication position and a third flow passage communication position that opens the third flow passage communication region and closes the second flow passage communication region,
One of the valve blade portions has a planar second flow passage side valve blade surface that approaches the second flow passage side partition wall surface when the valve body is rotated to the second flow passage communicating position. Have
The second flow path side valve vane surface is provided with the second flow path side valve vane surface and the second flow path side partition wall surface which are close to each other when the valve body is rotated to the second flow path communicating position. The second flow path side valve is provided with a second flow path side convex portion that is in contact with the second flow path side partition wall surface so as to close a gap from the second flow path to the third flow path. It is provided so as to be continuous along the wing surface,
The other valve blade portion is a flat third flow passage side valve blade surface that approaches the third flow passage side partition surface when the valve body is rotated to the third flow passage communicating position. Have
The third flow passage side valve vane surface does not include the third flow passage side valve vane surface and the third flow passage side partition wall surface which are close to each other when the valve body is rotated to the third flow passage communicating position. The third flow path side valve is provided with a third flow path side convex portion that is in contact with the third flow path side partition wall surface so as to close a gap from the third flow path to the second flow path. It is provided so as to be continuous along the wing surface,
Flow path switching valve. The flow path switching valve according to claim 1, wherein
The valve body is formed in an L-shape by the valve blade portion on one side and the valve blade portion on the other side when viewed in the valve axis direction.
Flow path switching valve. The flow path switching valve according to claim 1 or 2,
The second flow path side convex portion and the third flow path side convex portion provided on the valve body are formed by different members that are members different from the valve body,
Flow path switching valve. The flow path switching valve according to any one of claims 1 to 3,
An exhaust gas introduction passage having one end connected to an exhaust pipe of an internal combustion engine and the other end connected to the first main flow passage of a branching portion for branching the first main flow passage into two flow passages;
The branch portion,
Two said channels,
An EGR cooler which is provided in one of the two flow paths and cools the exhaust gas flowing in the flow paths;
A merging portion that joins the two flow channels into a second main flow channel,
An intake introduction path having one end connected to the second main flow path of the confluence portion and the other end connected to an intake pipe of the internal combustion engine;
Used in the branching portion or the merging portion,
Flow path switching valve.

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