charger

Abstract

In the present invention, a supercharger comprises: a compressor and a turbine connected via a rotating shaft; a first exhaust gas inlet channel and a second exhaust gas inlet channel for supplying exhaust gas to the turbine; a communication channel through which a central part of the first exhaust gas inlet channel and a central part of the second exhaust gas inlet channel communicate; a bypass channel through which the exhaust gas in the communication channel is discharged to an exhaust gas flow path; and an opening / closing valve provided in a section through which the communication channel and the bypass channel communicate, wherein the opening / closing valve is capable of enabling and prohibiting communication with the communication channel and of enabling and prohibiting communication between the communication channel and the bypass channel.The opening / closing valve is provided with a communication groove along a direction that crosses the opening / closing direction of the opening / closing valve on an outer circumferential section.

Description

Technical field

[0001] The present disclosure relates to a turbocharger and a process. State of the art

[0002] A turbocharger is configured so that a compressor and a turbine are integrally connected by a rotating shaft and rotatably mounted in a housing. The turbocharger spins the turbine using exhaust gas; the turbine's rotational force is transmitted via the rotating shaft to the compressor, which then pressurizes the air to produce compressed air, thus turbocharging the engine.

[0003] The turbocharger is a twin-screw type design with two spirally shaped exhaust gas inlet channels. These two channels supply exhaust gas to the turbine. The two exhaust gas inlet channels are connected to the turbine and communicate with each other via a communication channel in an intermediate section. This communication channel also communicates with an exhaust gas flow path via a bypass channel. A normally open / closed valve is located in the communication section between the communication channel and the bypass channel. When the valve is closed, communication between the two exhaust gas inlet channels and the bypass channel is blocked.On the other hand, when the opening / closing valve is open, the two exhaust gas inlet channels communicate with each other via the communication channel, and the exhaust gas inlet channels communicate with the bypass channel via the communication channel. Such a turbocharger is described, for example, in PTL 1. List of citations from patent literature

[0004] [PTL 1] German patent application no. 102013002894 Summary of the invention: Technical problem

[0005] In a twin-screw turbocharger, when the open / close valve is in a range from a low to a medium opening, the two exhaust gas inlet channels communicate with each other, allowing exhaust gas to circulate through them. However, at this point, some of the exhaust gas flowing through the two inlet channels also flows through the communication channel to the bypass channel. This results in a decrease in the flow rate of the exhaust gas supplied to the turbine from the inlet channels, thus reducing the turbocharger's efficiency.

[0006] The present disclosure has been made to solve the problems described above, and one objective of the present disclosure is to provide a turbocharger that improves efficiency by reducing the flow rate of an exhaust gas to a bypass channel in a range of low opening degree to a medium opening degree of an opening / closing valve. Solution to the problem

[0007] According to one aspect of the present disclosure, in order to achieve the above task, a turbocharger is provided which comprises a compressor and a turbine connected to each other via a rotating shaft, a first exhaust gas inlet channel and a second exhaust gas inlet channel through which exhaust gas is supplied to the turbine, a communication channel which allows an intermediate section of the first exhaust gas inlet channel and an intermediate section of the second exhaust gas inlet channel to communicate with each other, a bypass channel through which the exhaust gas in the communication channel is discharged to an exhaust gas flow path, and an opening / closing valve which is provided in a communication section between the communication channel and the bypass channel and which is capable ofto communicate with the communication channel and to block the communication channel and to allow the communication channel and the bypass channel to communicate with each other and to block the communication channel and the bypass channel, wherein a communication groove is provided along a direction that intersects an opening / closing direction of the opening / closing valve in an outer circumferential section of the opening / closing valve. Advantageous effects of the invention

[0008] With the turbocharger of the present disclosure, efficiency can be improved by reducing the flow rate of the exhaust gas to the bypass channel in the range of low opening degree up to the medium opening degree of the opening / closing valve. Brief description of the drawings Fig. Figure 1 is a schematic view showing a turbocharger of the present embodiment. Fig. Figure 2 is a schematic view showing an exhaust duct at the turbocharger. Fig. Figure 3 is a front view showing an opening / closing valve. Fig. Figure 4 is a top view showing the opening / closing valve. Fig. Figure 5 is a cross-sectional view showing the open / close valve in a closed state. Fig. Figure 6 is a cross-sectional view along line VI-VI of Fig. 5, which shows the closed state of the opening / closing valve. Fig. Figure 7 is a cross-sectional view showing a slightly open state of the opening / closing valve. Fig. Figure 8 is a graph showing a communication range in relation to a valve opening degree of the opening / closing valve. Fig. Figure 9 is a graph showing a bypass area in relation to the valve opening degree of the opening / closing valve. Fig. Figure 10 is a graph showing a flow rate in a communication direction relative to a bypass flow rate. Fig. Figure 11 is a graph showing turbine efficiency in relation to engine speed. Fig. Figure 12 is a graph showing fuel consumption in relation to engine speed. Fig. Figure 13 is a front view showing a first modification example of the opening / closing valve. Fig. Figure 14 is a front view showing a second modification example of the opening / closing valve. Fig. Figure 15 is a front view showing a third modification example of the opening / closing valve. Fig. Figure 16 is a top view showing a fourth modification example of the open / close valve. Description of embodiments

[0009] A preferred embodiment of the present disclosure is described in detail below with reference to the drawings. The present disclosure is not limited by the embodiment, and in a case where there are several embodiments, the present disclosure also includes configurations in which the respective embodiments are combined. Furthermore, the components of the embodiments include those that can be readily assumed by those skilled in the art, those that are essentially the same, and those that have a so-called equivalent scope of protection. [First embodiment] <turbolader>

[0010] Fig. Figure 1 is a schematic view showing a turbocharger of the present embodiment.

[0011] The turbocharger is mounted on a vehicle, such as an automobile, that has a reciprocating piston engine (hereinafter simply referred to as an engine), which is an internal combustion engine, as its power source. The turbocharger is a device that compresses intake air (air) using exhaust gas from the engine.

[0012] As in Fig. As shown in Figure 1, an engine 10 is a multi-cylinder internal combustion engine. An engine housing 11 is provided with several cylinder bores 12, and pistons 13 are mounted such that they are movable up and down in the cylinder bores 12 via cylinder liners (not shown). Although not shown, a crankshaft is rotatably mounted on a lower section of the engine housing 11, and each of the pistons 13 is connected to the crankshaft via a connecting rod 14.

[0013] A combustion chamber 15 is configured such that it is divided by a wall surface and a lower surface of the cylinder bore 12 and an end face of the piston 13. An inlet port 16 and an exhaust port 17 are formed at the top of the combustion chamber 15, and an inlet valve 18 and an exhaust valve 19 are provided accordingly at the inlet port 16 and the exhaust port 17. The inlet valve 18 and the exhaust valve 19 are mounted so that they are movable along an axial direction and are mounted so that they open in one direction (upwards). Fig. 1), in which the intake port 16 and the exhaust port 17 are closed, are pre-tensioned. The intake valve 18 and the exhaust valve 19 can open and close the intake port 16 and the exhaust port 17 when an intake cam and an exhaust cam of an intake camshaft and an exhaust camshaft (not shown) are acted upon. In addition, the combustion chamber 15 is provided at the top with a fuel injector 20. The fuel injector 20 can inject high-pressure fuel into the combustion chamber 15.

[0014] For this reason, the engine 10 performs four strokes, comprising an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke, while the crankshaft rotates twice. At this time, the intake camshaft and the exhaust camshaft rotate once, and the intake valve 18 and the exhaust valve 19 open and close the intake port 16 and the exhaust port 17, respectively.

[0015] An intake air duct 21 is connected to the inlet port 16, and an exhaust air duct 22 is connected to the outlet port 17 on the engine housing 11. A turbocharger 23 is arranged between the intake air duct 21 and the exhaust air duct 22. The turbocharger 23 comprises a compressor unit 24, a turbine unit 25, a bearing unit 26, and an exhaust bypass device 27.

[0016] The compressor unit 24 compresses intake air (air) introduced by an air filter (not shown) and directs the intake air to the combustion chamber 15. The compressor unit 24 comprises a compressor wheel (compressor) 31 and a compressor housing 32. The compressor wheel 31 is mounted in the compressor housing 32 and is rotatably mounted about an axis O. The compressor wheel 31 causes intake air A, flowing from one side of the axis O due to centrifugal force, to flow through it while being compressed from an inner to an outer side in a radial direction around the axis O. Compressed air B, which has been compressed by the compressor wheel 31, is discharged to the outer side in a radial direction around the axis O and is fed into the intake air duct 21.

[0017] The compressor housing 32 has a wheel housing section 33, an intake inlet channel 34, and an intake outlet channel 35. The compressor wheel 31 is rotatably mounted and received in the wheel housing section 33. The intake inlet channel 34 is connected to the wheel housing section 33 on one side of the axis O of the compressor wheel 31. The intake outlet channel 35 is connected to the wheel housing section 33 on the outside in the radial direction around the axis O of the compressor wheel 31. The intake outlet channel 35 is connected to the intake air channel 21. The compressed air B is introduced from the intake air channel 21 through the intake outlet channel 35 into the combustion chamber 15.

[0018] The turbine unit 25 receives rotational force from an exhaust gas C that is discharged from the combustion chamber 15. The turbine unit 25 comprises a turbine wheel (turbine) 41 and a turbine housing 42. The turbine wheel 41 is mounted in the turbine housing 42 and is rotatably mounted about the axis O. The turbine wheel 41 is rotated by the exhaust gas C, which is discharged from the exhaust duct 22 towards the inside in a radial direction about the axis O. The exhaust gas C, which has rotated the turbine wheel 41, flows from the other side of the axis O towards the outside.

[0019] The turbine housing 42 comprises a wheel housing section 43, an exhaust gas inlet duct 44, and an exhaust gas discharge duct 45. The turbine wheel 41 is rotatably mounted and received in the wheel housing section 43. The exhaust gas inlet duct 44 is connected to the exhaust duct 22. The exhaust gas inlet duct 44 is connected to the wheel housing section 43 on the outside of the turbine wheel 41 in the radial direction around axis O. The exhaust gas discharge duct 45 is connected to the wheel housing section 43 on the opposite side of the turbine wheel 41 from axis O. The exhaust gas C is discharged through the exhaust gas discharge duct 45.

[0020] The bearing unit 26 comprises a rotating shaft 51 and a bearing housing (not shown). The compressor wheel 31 is attached to one side of the shaft 0, and the turbine wheel 41 is attached to the other side of the shaft 0. The compressor wheel 31 and the turbine wheel 41 can rotate integrally through the rotating shaft 51. The bearing housing rotatably accommodates the rotating shaft 51. A plain bearing, a rolling bearing, or the like is used as the bearing. The bearing housing is connected to the compressor housing 32 and the turbine housing 42.

[0021] The exhaust gas bypass device 27 adjusts the flow rate of the exhaust gas C, which is to be bypassed by the turbine unit 25, i.e., the flow rate of the exhaust gas C to be supplied to the turbine wheel 41, according to an intake air pressure in the intake air duct 21. In other words, the exhaust gas bypass device 27 directs the additional exhaust gas directly to the exhaust gas discharge duct 45 without supplying the additional exhaust gas to the turbine unit 25.

[0022] For this reason, in the engine housing 11, when intake air (air) is supplied to the combustion chamber 15 from the intake air duct 21, the air is compressed by the rising pistons 13 to create compressed air, and the high-pressure fuel is injected into the compressed air by the fuel injector 20. The high-pressure air and the high-pressure fuel are then mixed, and the mixture is ignited and combusted. The resulting combustion gas is released as exhaust gas C to the exhaust duct 22. At this point, the exhaust gas C released from the combustion chamber 15 rotates the turbine wheel 41 in the turbocharger 23. A rotational force from the turbine wheel 41 is then transmitted via the drive shaft 51 to the compressor wheel 31 to rotate the compressor wheel 31, and the intake air is pressurized to perform turbocharging at the combustion chamber 15.Furthermore, the exhaust gas bypass device 27 directs the exhaust gas C to the exhaust gas discharge channel 45 without supplying the exhaust gas C to the turbine unit 25 according to the intake air pressure in the intake air channel 21. <abgaskanal>

[0023] Fig. Figure 2 is a schematic view showing an exhaust duct at the turbocharger.

[0024] As in Fig. As shown in Figure 2, the turbine unit 25 of the turbocharger 23 is configured such that the turbine wheel 41 is received in the turbine housing 42 and is rotatably mounted. The turbine housing 42 includes the wheel housing section 43, the exhaust gas inlet duct 44, and the exhaust gas outlet duct 45. The turbocharger 23 has a twin-screw structure. That is, the exhaust gas inlet duct 44 has two spiral exhaust gas inlet channels 61 and 62. For example, exhaust gas from the first and fourth cylinders (not shown) of the four cylinders (combustion chambers 15) of the engine 10 is introduced into the first exhaust gas inlet channel 61. Furthermore, exhaust gas from the second and third cylinders (not shown) of the four cylinders of the engine is introduced into the second exhaust gas inlet channel 62.

[0025] The first exhaust gas inlet duct 61 and the second exhaust gas inlet duct 62 are arranged side by side. Upstream sides of the exhaust gas flow directions C1 and C2 of the first exhaust gas inlet duct 61 and the second exhaust gas inlet duct 62 are connected to the exhaust air duct 22 (see Fig. 1) A downstream side of the first exhaust gas inlet channel 61 in the direction of flow of the exhaust gas C1 is connected to the wheel housing section 43 on one side in the radial direction, and a downstream side of the direction of flow of the exhaust gas C2 of the second exhaust gas inlet channel 62 is connected to the wheel housing section 43 on the other side in the radial direction.

[0026] The first exhaust gas inlet channel 61 and the second exhaust gas inlet channel 62 are connected to each other by a communication channel 63. The communication channel 63 has a first branch channel 64, a second branch channel 65, and a communication section 66. The first branch channel 64 branches off from an intermediate section of the first exhaust gas inlet channel 61, and the second branch channel 65 branches off from an intermediate section of the second exhaust gas inlet channel 62. The communication section 66 causes downstream end sections of the first branch channel 64 and the second branch channel 65 to communicate with each other in the direction of exhaust gas flow C1.

[0027] The communication channel 63 is connected to an exhaust gas discharge channel (exhaust gas flow path) 45 via a bypass channel 67. An upstream end section of the bypass channel 67 in the direction of exhaust gas flow C1 communicates with the communication section 66, and the bypass channel 67, which has a downstream end section in the direction of exhaust gas flow C1 that communicates with the exhaust gas discharge channel 45, can direct a portion or all of the exhaust gas C1 flowing in the first exhaust gas inlet channel 61, or the exhaust gas C2 flowing in the second exhaust gas inlet channel 62, to the exhaust gas discharge channel 45, bypassing the turbine wheel 41 without feeding a portion or all of the exhaust gas C1 or C2 to the turbine wheel 41.

[0028] The communication channel 63 is equipped with an open / close valve 68. The open / close valve 68 is located in the communication section 66 of the communication channel 63. The open / close valve 68 is situated in the communication section 66 between the communication channel 63 and the bypass channel 67. It can communicate with and block the communication channel 63, and it can also allow communication channel 63 and the bypass channel 67 to communicate with each other and block both. That is, when the open / close valve 68 is closed, communication between the first branch channel 64 and the second branch channel 65, which form the communication channel 63, is blocked, as is communication between the first branch channel 64 and the second branch channel 65 and the bypass channel 67.On the other hand, when the opening / closing valve 68 is open, the first branch channel 64 and the second branch channel 65, which form the communication channel 63, communicate with each other, and the first branch channel 64, the second branch channel 65 and the bypass channel 67 communicate with each other.

[0029] The exhaust gas bypass device 27 is configured with the bypass channel 67 and the opening / closing valve 68.

[0030] For this reason, when the opening / closing valve 68 is closed, communication between the first branch channel 64 and the second branch channel 65 is blocked. Accordingly, exhaust gas C1 is supplied to the turbine wheel 41 from the first exhaust inlet channel 61, and exhaust gas C2 is supplied to the turbine wheel 41 from the second exhaust inlet channel 62. Conversely, when the opening / closing valve 68 is open, the first branch channel 64 and the second branch channel 65 communicate with each other and with the bypass channel 67. Therefore, the pressure of exhaust gas C1 flowing in the first exhaust inlet channel 61 and the pressure of exhaust gas C2 flowing in the second exhaust inlet channel 62 are equalized by the communication section 66, and the flow rates of exhaust gases C1 and C2 in the respective exhaust inlet channels 61 and 62 are balanced.Furthermore, the exhaust gas C1, which flows in the first exhaust gas inlet channel 61, and the exhaust gas C2, which flows in the second exhaust gas inlet channel 62, flow from the bypass channel 67 to the exhaust gas discharge channel 45. Then the flow rate of the exhaust gas C1, which is supplied to the turbine wheel 41 from the first exhaust gas inlet channel 61, and the flow rate of the exhaust gas C2, which is supplied to the turbine wheel 41 from the second exhaust gas inlet channel 62, decrease. <Konfiguration von Öffnungs- / Schließventil>

[0031] Fig. Figure 3 is a front view showing the opening / closing valve, and Fig. Figure 4 is a top view showing the opening / closing valve.

[0032] As in Fig. 3 and Fig. As shown in Figure 4, the opening / closing valve 68 includes a flanged section 71, a valve body 72, a support section 73 and a cylindrical section 74.

[0033] The flange section 71 has a disc shape around an axis O1. The valve body 72 is integrally connected to a flat surface section of the flange section 71. The valve body 72 has a column shape around the axis O1. The valve body 72 has a tapered shape, from which an outer diameter decreases towards one side of the axis O1. The valve body 72 has an outer circumferential surface 72a and a bottom surface 72b. The outer circumferential surface 72a has a shape that convexes outwards in the axial direction. The bottom surface 72b has a flat shape and continues smoothly to the outer circumferential surface 72a via a curved section 72c. That is, the valve body 72 has a projecting shape, from which the outer diameter decreases from one side of the flange section 71 to one side of the bottom surface 72b, and has a tapered shape.

[0034] The cylindrical section 74 is integrally connected to the flanged section 71 via the support section 73. The cylindrical section 74 has a cylindrical shape about an axis O2. The axis O2 is perpendicular to the axis O1 and is positioned such that it deviates from the axis O1 in the radial direction of the flanged section 71 and the valve body 72. In the cylindrical section 74, one end section of the axis O2 is connected to the other flat surface section of the flanged section 71 via the support section 73. A stem 75 is fitted into the cylindrical section 74 and is rotatably mounted via a bearing (not shown). That is, the open / close valve 68 has the valve body 72, which extends along one direction of the axis O1 and is rotatably mounted about the axis O2.

[0035] A communication groove 76, extending along a direction that intersects an opening / closing direction (a direction along the axis O1) of the opening / closing valve 68, is provided in an outer circumferential section of the opening / closing valve 68. The communication groove 76 is located in an outer circumferential section of the valve body 72 on a side opposite the axis O2 with respect to the axis O1. That is, the communication groove 76 is located in the outer circumferential section of the valve body 72 that is furthest from the axis O2, which is a center of rotation of the opening / closing valve 68. The communication groove 76 extends along a circumferential direction in the outer circumferential section of the valve body 72 of the opening / closing valve 68, and a groove base section 76a has a linear shape.This means that the communication groove 76 is provided in a part of the outer circumferential section of the valve body 72 of the opening / closing valve 68. As shown in . Fig. 2 and Fig. As shown in Figure 3, when the opening / closing valve 68 blocks the communication channel 63 and the communication channel 63 and the bypass channel 67 are blocked, the communication groove 76 communicates partially with the communication channel 63, that is, it communicates partially with the first branch channel 64 and the second branch channel 65.

[0036] In this case, it is preferred that a length La from an upper surface 72d of the opening / closing valve 68 to the center of the communication groove 76 is 0.3 times or more a length L in the opening / closing direction (the direction along the axis O1) of the opening / closing valve 68. Furthermore, it is preferred that a length Lb from the bottom surface 72b of the opening / closing valve 68 to the communication groove 76 is in a range of 1.0 to 1.2 times the length L from the bottom surface 72b of the opening / closing valve 68 to an inner surface of the communication channel 63 on an opening-direction side of the opening / closing valve 68. Furthermore, it is preferred that the width of the communication groove 76 lies in a range of 0.1 times to 0.3 times the length L in the opening / closing direction (the direction along the axis O1) of the opening / closing valve 68. <Betrieb von Öffnungs- / Schließventil>

[0037] Fig. Figure 5 is a cross-sectional view showing the open / close valve in a closed state. Fig. Figure 6 is a cross-sectional view along line VI-VI of Fig. 5, which shows the closed state of the opening / closing valve, and Fig. Figure 7 is a cross-sectional view showing a slightly open state of the opening / closing valve.

[0038] As in Fig. 5 and Fig. As shown in Figure 6, the open / close valve 68 is mounted by a housing 81. That is, the open / close valve 68 is mounted such that it is rotatable about the axis O2 with respect to the housing 81. The open / close valve 68 has a projecting shape that can be fitted from one side of bypass channel 67 with respect to an opening 82 to cause communication channel 63 and bypass channel 67 to communicate with each other. The axis O1 of the open / close valve 68 and an axis O3, which is a center of the opening 82, essentially coincide. The opening / closing valve 68 is rotatable about the axis O2, which is perpendicular to an opening direction of the opening 82 (a direction along the axis O3) and is located as a rotation axis at a position that deviates from the center (axis O3) of the opening 82 to one side in the radial direction.

[0039] The communication groove 76 is provided in the outer circumferential section of the open / close valve 68 (valve body 72), which deviates radially from the center (axis O3) of the opening 82 to the opposite side. The communication groove 76 extends along the circumferential direction in the outer circumferential section of the valve body 72 of the open / close valve 68. A concave section 83 is provided on an inner surface 63a of the communication channel 63, which faces the opening 82 in the radial direction. When the open / close valve 68 is closed, a bottom section (bottom surface 72b) of the valve body 72 is fitted into the concave section 83. That is, the bottom surface 72b of the valve body 72 is positioned below the inner surface 63a of the communication channel 63 when the open / close valve 68 is closed.Furthermore, the communication groove 76 is provided along the opening / closing direction of the opening / closing valve 68, i.e. a direction perpendicular to the exhaust gas C that flows from the communication channel 63 to the bypass channel 67 when the opening / closing valve 68 is open.

[0040] When the open / close valve 68 is open, the exhaust gas C, flowing from the communication channel 63 to the bypass channel 67, flows along the outer circumferential surface of the valve body 72 of the open / close valve 68. At this point, the exhaust gas C interferes with the communication groove 76, which is formed in a concave shape in the outer circumferential section of the open / close valve 68. As a result, the flow of exhaust gas C from the communication channel 63 to the bypass channel 67 is obstructed, and the flow rate of the exhaust gas C from the communication channel 63 to the bypass channel 67 is reduced.

[0041] Fig. Figure 6 is a cross-sectional view of the communication channel 63, showing a closed state of the opening / closing valve 68, and Fig. Figure 7 is a cross-sectional view of the communication channel 63, showing a slightly open state of the opening / closing valve 68. The cross-sectional views of Fig. 6 and Fig. However, Figure 7 shows projection views of the communication channel 63 and the opening / closing valve 68 when the second branch channel 65 is viewed from one side of the first branch channel 64. Therefore, when describing Fig. 6 and Fig. 7 stipulates that communication is established in the projection state.

[0042] As in Fig. As shown in Figure 6, when the open / close valve 68 closes the communication channel 63, the flanged section 71 comes into close contact with the flat surface section of the housing 81 on the side of bypass channel 67. The valve body 72 is fitted into the opening 82 and is closed, and the bottom section (bottom surface 72b) is fitted into the concave section 83 of the communication channel 63. For this reason, communication between the first branch channel 64 and the second branch channel 65 is blocked, as is communication between the first branch channel 64 and the second branch channel 65 and the bypass channel 67. However, since the communication groove 76 is provided in the valve body 72, the open / close valve 68 communicates with the communication channel 63; that is, the first branch channel 64 and the second branch channel 65 communicate with each other. Fig. The area shown by diagonal lines (6) is a communication area S1.

[0043] On the other hand, as in Fig. Figure 7 shows that when the open / close valve 68 slightly opens the communication channel 63, the flanged section 71 is slightly separated from the flat surface section of the housing 81 on the side of bypass channel 67, the valve body 72 is fitted into the opening 82 so that it is almost closed, and the bottom section (bottom surface 72b) is slightly separated from the concave section 83 of the communication channel 63. However, since the concave section 83 is provided in the communication channel 63, the first branch channel 64 and the second branch channel 65 are continuously blocked. At this point, because the communication groove 76 is provided in the valve body 72, the open / close valve 68 communicates with the communication channel 63; that is, the first branch channel 64 and the second branch channel 65 communicate with each other. The Fig. The area shown by diagonal lines 7 is a communication area S2. The communication area S2, when the opening / closing valve 68 is slightly open, is smaller than the communication area S1, when the opening / closing valve 68 is opened and closed. <Betriebseffekte von Öffnungs- / Schließventil>

[0044] Fig. Figure 8 is a graph showing a communication area in relation to a valve opening degree of the open / close valve. Here, the communication area is communication area S1 or S2 of communication channel 63, which is defined by communication groove 76, as shown in the projection views of Fig. 6 and Fig. 7 is described, is formed. In addition, there is in Fig. 8 a dashed line indicates an opening / closing valve of the prior art without the communication groove 76, and a solid line indicates the opening / closing valve 68 of the present embodiment with the communication groove 76.

[0045] As indicated by the dotted line in Fig. As shown in Figure 8, in the turbocharger having the prior art open / close valve, the communication range increases uniformly as the valve opening degree increases from the point at which the open / close valve closes (valve opening degree 0). On the other hand, as shown by the solid line in Fig. Figure 8 shows that in the turbocharger 23, which has the opening / closing valve 68 of the present embodiment, the communication range decreases and then increases as the valve opening degree increases from the point at which the opening / closing valve 68 closes (valve opening degree 0). For this reason, the amount of exhaust gas C communicating in the first branch channel 64 and the second branch channel 65 is limited when the opening / closing valve 68 is slightly open.

[0046] Fig. Figure 9 is a graph showing a bypass area in relation to the valve opening degree of the open / close valve. Here, the bypass area is a communication area between communication channel 63 and bypass channel 67. Furthermore, in Fig. 9 a dashed line indicates an opening / closing valve of the prior art without the communication groove 76, and a solid line indicates the opening / closing valve 68 of the present embodiment with the communication groove 76.

[0047] As indicated by the dotted line in Fig. As shown in Figure 9, in the turbocharger having the prior art open / close valve, the bypass area increases uniformly as the valve opening degree increases from the point at which the open / close valve closes (valve opening degree 0). On the other hand, as shown by the solid line in Fig. Figure 9 shows that in the turbocharger 23, which has the opening / closing valve 68 of the present embodiment, the bypass area increases uniformly as the valve opening degree increases from the point at which the opening / closing valve 68 closes (valve opening degree 0). However, if the valve opening degree is large, the bypass area is smaller in the case of the prior art opening / closing valve.

[0048] Fig. Figure 10 is a graph showing a flow rate in a communication direction relative to a bypass flow rate. Here, the bypass flow rate is the flow rate of the exhaust gas C flowing from communication channel 63 to bypass channel 67, and the flow rate in the communication direction is the flow rate of the exhaust gas C flowing between the first branch channel 64 and the second branch channel 65. Furthermore, in Fig. 10 a dashed line indicates an opening / closing valve of the prior art without the communication groove 76, and a solid line indicates the opening / closing valve 68 of the present embodiment with the communication groove 76.

[0049] As indicated by the dotted line in Fig. As shown in Figure 10, in the turbocharger having the prior art open / close valve, when the bypass exhaust gas quantity C increases with an increase in the opening degree of the open / close valve, the flow rate in the communication direction increases with an increase in the bypass quantity. At this point, the bypass exhaust gas quantity C increases in a range from a low opening degree to a medium opening degree of the open / close valve, and the flow rate in the communication direction does not increase sufficiently. On the other hand, as shown by the solid line in Figure 10, the bypass exhaust gas quantity C increases with a medium opening degree of the open / close valve. Fig. Figure 10 shows that in the turbocharger 23, which has the opening / closing valve 68 of the present embodiment, when the bypass quantity of the exhaust gas C increases with an increase in the opening degree of the opening / closing valve 68, the flow rate in the communication direction also increases with an increase in the bypass quantity. At this point, in a range from the low opening degree to the medium opening degree of the opening / closing valve 68, the degree of increase in the bypass quantity of the exhaust gas C is slower than that of the opening / closing valve of the prior art, and the flow rate in the communication direction is significantly increased.

[0050] In the range from the low opening degree to the medium opening degree of the opening / closing valve 68, the exhaust gas C flowing from the communication channel 63 to the bypass channel 67 interferes with the communication groove 76 formed in the outer circumferential section of the opening / closing valve 68, and the flow rate of the exhaust gas C flowing from the communication channel 63 to the bypass channel 67 is reduced. For this reason, the flow rate of the exhaust gas C flowing between the first branch channel 64 and the second branch channel 65, i.e., the flow rate in the communication direction, increases.

[0051] Fig. Figure 11 is a graph showing turbine efficiency in relation to engine speed. Fig. 11 a dashed line indicates the opening / closing valve of the prior art without the communication groove 76, and a solid line indicates the opening / closing valve 68 of the present embodiment with the communication groove 76.

[0052] As indicated by the dotted line in Fig. As shown in Figure 11, the turbine efficiency of the turbocharger, which has the prior art opening / closing valve, increases with an increase in engine speed. On the other hand, as shown by the solid line in Figure 11, the turbine efficiency of the turbocharger, which has the opening / closing valve of the prior art, increases with an increase in engine speed. Fig. Figure 11 shows that the turbine efficiency of the turbocharger 23, which has the opening / closing valve 68 of the present embodiment, increases with an increase in engine speed. At this point, the turbine efficiency is improved (increased) in a range from low engine speed to medium engine speed compared to the turbocharger having the opening / closing valve of the prior art.

[0053] Fig. Figure 12 is a graph showing fuel consumption in relation to engine speed. Fig. 11 a dashed line indicates the opening / closing valve of the prior art without the communication groove 76, and a solid line indicates the opening / closing valve 68 of the present embodiment with the communication groove 76.

[0054] As in Fig. Figure 12 shows that, for the engine on which the turbocharger, which has the opening / closing valve of the prior art, is mounted, the fuel consumption in relation to an increase in engine speed is shown by the dashed line in Fig. Figure 12. On the other hand, in the case of the engine 10, on which the turbocharger 23, which has the opening / closing valve 68 of the present embodiment, is mounted, the fuel consumption in relation to an increase in engine speed is shown by the solid line in Fig. Figure 12 shows that the engine 10 of the present embodiment has improved (reduced) fuel consumption compared to the prior art engine. <modifikationsbeispiele>

[0055] In the embodiment described above, the communication groove 76 is provided along the circumferential direction in the outer circumferential section of the valve body 72 of the opening / closing valve 68. However, the present disclosure is not limited to this configuration.

[0056] Fig. Figure 13 is a front view showing a first modification example of the opening / closing valve.

[0057] As in Fig. As shown in Figure 13, an open / close valve 68A comprises the flanged section 71, the valve body 72, the support section 73, and the cylindrical section 74. A communication groove 76A, extending along a direction that intersects an open / close direction (a direction along the axis O1) of the open / close valve 68A, is provided in an outer circumferential section of the open / close valve 68A. The communication groove 76A extends along a circumferential direction in the outer circumferential section of the valve body 72 of the open / close valve 68A. That is, the communication groove 76A extends over the entire circumference of the outer circumferential section of the valve body 72 of the open / close valve 68A.

[0058] As in Fig. 5 and Fig. As shown in Figure 13, when the opening / closing valve 68A is open, the exhaust gas C, flowing from the communication channel 63 to the bypass channel 67, flows along an outer circumferential surface of the valve body 72 of the opening / closing valve 68A. At this point, the exhaust gas C interferes with the communication groove 76A, which is formed in a concave shape around the entire circumference of the outer circumferential section of the opening / closing valve 68A. As a result, the flow of exhaust gas C from the communication channel 63 to the bypass channel 67 through the communication groove 76A is obstructed, and the flow rate of the exhaust gas C from the communication channel 63 to the bypass channel 67 is reduced. Furthermore, since the communication groove 76A is provided over the entire circumference of the outer circumferential section of the valve body 72 of the opening / closing valve 68A, processing performance can be improved and processing costs can be reduced.

[0059] Fig. Figure 14 is a front view showing a second modification example of the opening / closing valve.

[0060] As in Fig. As shown in Figure 14, an open / close valve 68B comprises the flanged section 71, the valve body 72, the support section 73, and the cylindrical section 74. A communication groove 76B, extending along a direction intersecting an open / close direction (a direction along the axis O1) of the open / close valve 68B, is provided in an outer circumferential section of the open / close valve 68B. The communication groove 76B includes a first communication groove 91 and a second communication groove 92. The first communication groove 91 and the second communication groove 92 are spaced apart along one direction of the axis O1 and are parallel to each other. The first communication groove 91 is wider along the axis O1 and longer circumferentially than the second communication groove 92.The communication groove 76B (the first communication groove 91 and the second communication groove 92) is provided in the outer circumferential section of the valve body 72 on a side opposite the axis O2 with respect to the axis O1.

[0061] As in Fig. 5 and Fig. As shown in Figure 14, when the opening / closing valve 68B is open, the exhaust gas C, flowing from the communication channel 63 to the bypass channel 67, flows along an outer circumferential surface of the valve body 72 of the opening / closing valve 68B. At this point, the exhaust gas C interferes with the communication groove 76B, which is formed in two stages in a concave shape in the outer circumferential section of the opening / closing valve 68B, namely the first communication groove 91 and the second communication groove 92. As a result, the flow of exhaust gas C from the communication channel 63 to the bypass channel 67 through the communication groove 76B is obstructed, and the flow rate of the exhaust gas C from the communication channel 63 to the bypass channel 67 is reduced.

[0062] Fig. Figure 15 is a front view showing a third modification example of the opening / closing valve.

[0063] As in Fig. As shown in Figure 15, an open / close valve 68C comprises the flanged section 71, the valve body 72, the support section 73, and the cylindrical section 74. A communication groove 76C, extending along a direction that intersects an opening / closing direction (a direction along the axis O1) of the open / close valve 68C, is provided in an outer circumferential section of the open / close valve 68C. The communication groove 76C is located in an outer circumferential section of the valve body 72 on a side opposite the axis O2 with respect to the axis O1. That is, the communication groove 76C is provided in a portion of the outer circumferential section of the valve body 72 of the open / close valve 68C.Furthermore, the communication groove 76C is open with respect to a plane perpendicular to the axis O1 towards the side of flange section 71. The communication groove 76C can also be open with respect to a plane perpendicular to the axis O1 towards a side opposite flange section 71 (side of bottom surface 72b).

[0064] As in Fig. 5 and Fig. As shown in Figure 15, when the open / close valve 68C is open, the exhaust gas C, flowing from the communication channel 63 to the bypass channel 67, flows along an outer circumferential surface of the valve body 72 of the open / close valve 68C. At this point, the exhaust gas C interferes with the communication groove 76C, which is formed in a concave shape around the entire circumference of the outer circumferential section of the open / close valve 68C. As a result, the flow of exhaust gas C from the communication channel 63 to the bypass channel 67 through the communication groove 76C is obstructed, and the flow rate of the exhaust gas C from the communication channel 63 to the bypass channel 67 is reduced.

[0065] Fig. Figure 16 is a top view showing a fourth modification example of the opening / closing valve.

[0066] As in Fig. As shown in Figure 16, an open / close valve 68D comprises the flanged section 71, the valve body 72, the support section 73, and the cylindrical section 74. A communication groove 76D, extending along a direction intersecting an opening / closing direction (a direction along the axis O1) of the open / close valve 68D, is provided in an outer circumferential section of the open / close valve 68D. The communication groove 76D is located in an outer circumferential section of the valve body 72 on a side opposite the axis O2 with respect to the axis O1. The communication groove 76D extends along a circumferential direction in the outer circumferential section of the valve body 72 of the open / close valve 68D, and the groove base section 76a has a curved shape. This means that the communication groove 76D is provided in a part of the outer circumferential section of the valve body 72 of the opening / closing valve 68D.

[0067] As in Fig. 5 and Fig. As shown in Figure 16, when the opening / closing valve 68D is open, the exhaust gas C, flowing from the communication channel 63 to the bypass channel 67, flows along an outer circumferential surface of the valve body 72 of the opening / closing valve 68D. At this point, the exhaust gas C interferes with the communication groove 76D, which is formed in a concave shape around the entire circumference of the outer circumferential section of the opening / closing valve 68D. As a result, the flow of exhaust gas C from the communication channel 63 to the bypass channel 67 through the communication groove 76D is obstructed, and the flow rate of the exhaust gas C from the communication channel 63 to the bypass channel 67 is reduced. [Operational effects of the present embodiment]

[0068] A turbocharger according to a first aspect comprises the compressor wheel 31 and the turbine wheel 41, which are connected to each other via the rotating shaft 51, the first exhaust gas inlet channel 61 and the second exhaust gas inlet channel 62, through which the exhaust gas C is supplied to the turbine 41, the communication channel 63, through which an intermediate section of the first exhaust gas inlet channel 61 and an intermediate section of the second exhaust gas inlet channel 62 communicate with each other, the bypass channel 67, through which the exhaust gas C in the communication channel 63 is discharged to the exhaust gas discharge channel (exhaust gas flow path) 45, and the opening / closing valves 68, 68A, 68B, 68C and 68D, which are provided in the communication section 66 between the communication channel 63 and the bypass channel 67, can communicate with and block the communication channel 63 and can communicate with and block the communication channel 63 and can block bypass channel 67,wherein the communication grooves 76, 76A, 76B, 76C and 76D are provided along a direction that intersects the opening / closing direction of the opening / closing valve 68 in an outer circumferential section of the opening / closing valve 68.

[0069] With the turbocharger as described in the first aspect, in the region from the low opening degree to the medium opening degree of the opening / closing valves 68, 68A, 68B, 68C and 68D, the exhaust gas C, which flows from the communication channel 63 to the bypass channel 67, flows along the outer circumferential surfaces of the valve bodies 72 of the opening / closing valves 68, 68A, 68B, 68C and 68D. At this point, the exhaust gas C interferes with the communication grooves 76, 76A, 76B, 76C and 76D, which are provided in the outer circumferential sections of the opening / closing valves 68, 68A, 68B, 68C and 68D, and the flow of exhaust gas C to the bypass channel 67 is obstructed. For this reason, efficiency can be improved by reducing the flow rate of the exhaust gas C flowing from communication channel 63 to bypass channel 67.

[0070] A turbocharger according to a second aspect is the turbocharger according to the first aspect and furthermore communicates when the opening / closing valves 68, 68A, 68B, 68C and 68D block communication channel 63 and communication channel 63 and bypass channel 67 are blocked, the communication grooves 76, 76A, 76B, 76C and 76D with a part of communication channel 63. Accordingly, the circulation of exhaust gas C1 of the first exhaust gas inlet channel 61 and of exhaust gas C2 of the second exhaust gas inlet channel 62 is promoted, and efficiency can be improved.

[0071] A turbocharger according to a third aspect is the turbocharger according to the first or second aspect, and furthermore, the opening / closing valves 68, 68A, 68B, 68C, and 68D have a projecting shape that can be fitted from the side of bypass channel 67 into the opening 82, which allows communication channel 63 and bypass channel 67 to communicate with each other, and have the axis O2, which is perpendicular to the opening direction of the opening 82 and which is an axis of rotation at a position that deviates radially from the center (axis O3) of the opening 82 to one side, and the communication grooves 76, 76A, 76B, 76C, and 76D are in the outer circumferential sections of the opening / closing valves 68, 68A, 68B, 68C, and 68D, which extend radially from the center of the opening 82 to the other side Deviating in the radial direction is provided for.Accordingly, the exhaust gas C flowing from the communication channel 63 to the bypass channel 67 can be suitably disturbed by the communication slots 76, 76A, 76B, 76C and 76D, and the flow rate of the exhaust gas C flowing from the communication channel 63 to the bypass channel 67 can be reduced.

[0072] A turbocharger according to a fourth aspect is a turbocharger according to one of the first to third aspects, and furthermore, communication grooves 76, 76A, 76B, 76C and 76D are provided in the outer circumferential sections of the opening / closing valves 68, 68A, 68B, 68C and 68D in the circumferential direction. Accordingly, the exhaust gas C, which flows from the communication channel 63 to the bypass channel 67, can be suitably disturbed by the communication grooves 76, 76A, 76B, 76C and 76D.

[0073] A turbocharger according to a fifth aspect is the turbocharger according to one of the first to fourth aspects, and furthermore, the concave section 83, into which the bottom sections of the opening / closing valves 68, 68A, 68B, 68C and 68D are fitted when the opening / closing valves 68, 68A, 68B, 68C and 68D are closed, is provided in the inner surface of the communication channel 63, which faces the opening 82 in the radial direction. Accordingly, the circulation of the exhaust gas C1 of the first exhaust gas inlet channel 61 and the exhaust gas C2 of the second exhaust gas inlet channel 62 can be limited when the opening / closing valves 68, 68A, 68B, 68C and 68D are closed.

[0074] A turbocharger according to a sixth aspect is the turbocharger according to one of the first to fifth aspects, and furthermore, the communication channel 63 is configured such that the first branch channel 64, branching off from the first exhaust gas inlet channel 61, and the second branch channel 65, branching off from the second exhaust gas inlet channel 62, communicate with each other; the opening / closing valves 68, 68A, 68B, 68C, and 68D can allow the first branch channel 64 and the second branch channel 65 to communicate with each other and can block the first branch channel 64 and the second branch channel 65; and the communication range between the first branch channel 64 and the second branch channel 65 decreases and then increases as the valve opening degree increases from a time when the opening / closing valves 68, 68A, 68B, 68C, and 68D are closed.Accordingly, the circulation of the exhaust gas C1 of the first exhaust gas inlet channel 61 and the exhaust gas C2 of the second exhaust gas inlet channel 62 can be limited when the opening / closing valves 68, 68A, 68B, 68C and 68D are slightly open.

[0075] A turbocharger according to a seventh aspect is the turbocharger according to one of the first to sixth aspects, and furthermore, the lengths of the base surfaces of the opening / closing valves 68, 68A, 68B, 68C, and 68D to the centers of the communication grooves 76, 76A, 76B, 76C, and 76D are set to 0.3 times or more of the lengths in the opening / closing direction of the opening / closing valves 68, 68A, 68B, 68C, and 68D. Accordingly, the communication grooves 76, 76A, 76B, 76C, and 76D can be provided at suitable positions of the opening / closing valves 68, 68A, 68B, 68C, and 68D.

[0076] A turbocharger according to an eighth aspect is the turbocharger according to one of the first to seventh aspects and furthermore, a length of the bottom surfaces of the opening / closing valves 68, 68A, 68B, 68C and 68D to the communication grooves 76, 76A, 76B, 76C and 76D is set in a range of 1.0 times to 1.2 times a length from the bottom surfaces of the opening / closing valves 68, 68A, 68B, 68C and 68D to the inner surface of the communication channel 63 on the opening direction side of the opening / closing valves 68, 68A, 68B, 68C and 68D. Accordingly, the communication slots 76, 76A, 76B, 76C and 76D can be provided at suitable positions of the opening / closing valves 68, 68A, 68B, 68C and 68D. Reference symbol list 10 Motor 11 Engine housing 15 combustion chamber 21 Intake air duct 22 Exhaust duct 23 turbochargers 24 compressor unit 25 turbine units 26 storage units 27 Exhaust gas bypass device 31 Compressor wheel (compressor) 32 Compressor housings 33 Wheel housing section 34 Intake inlet duct 35 Intake discharge channel 41 Turbine wheel (turbine) 42 turbine housings 43 Wheel housing section 44 Exhaust gas inlet channel 45 Exhaust gas discharge channel 51 Rotary shaft 61 first exhaust gas inlet channel 62 Second exhaust gas inlet channel 63 Communication channel 64 first branch canal 65 second branch channel 66 Communication section 67 Bypass channel 68, 68A, 68B, 68C, 68D Opening / Closing Valve 71 Flange section 72 valve bodies 76, 76A, 76B, 76C, 76D communication groove 81 cases 82 Opening 83 concave section 91 first communication 92 second communication channel A Intake air B compressed air C, C1, C2 Exhaust gas S1, S2 Communication area O, O1, O2 axis QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102013002894

[0004] < / modifikationsbeispiele> < / abgaskanal> < / turbolader>

Claims

[1] Turbocharger, including: a compressor and a turbine connected to each other via a rotating shaft; a first exhaust gas inlet channel and a second exhaust gas inlet channel through which exhaust gas is supplied to the turbine; a communication channel that allows an intermediate section of the first exhaust gas inlet channel and an intermediate section of the second exhaust gas inlet channel to communicate with each other; a bypass channel through which the exhaust gas in the communication channel is discharged to an exhaust gas flow path; and an opening / closing valve that is provided in a communication section between the communication channel and the bypass channel and that is capable of communicating with the communication channel and blocking the communication channel and of allowing the communication channel and the bypass channel to communicate with each other and of blocking the communication channel and the bypass channel, wherein a communication groove is provided along a direction that intersects an opening / closing direction of the opening / closing valve in an outer circumferential section of the opening / closing valve. [2] Turbocharger according to claim 1, wherein the communication groove communicates with a part of the communication channel when the opening / closing valve blocks the communication channel and the communication channel and the bypass channel are blocked. [3] Turbocharger according to claim 1 or 2, wherein the opening / closing valve has a projecting shape which can be fitted from one side of bypass channel into an opening which allows the communication channel and the bypass channel to communicate with each other, and has an axis of rotation which is perpendicular to an opening direction of the opening and is located at a position which deviates from a center of the opening to one side in a radial direction, and the communication groove is provided in the outer circumferential section of the opening / closing valve which deviates from the center of the opening to the other side in the radial direction. [4] Turbocharger according to claim 3, wherein the communication groove is provided along a circumferential direction in the outer circumferential section of the opening / closing valve. [5] Turbocharger according to claim 3, wherein a concave section into which a bottom section of the opening / closing valve is fitted when the opening / closing valve is closed is provided in an inner surface of the communication channel which faces the opening in the radial direction. [6] Turbocharger according to claim 4, wherein the communication channel is configured such that a first branch channel branching off from the first exhaust gas inlet channel and a second branch channel branching off from the second exhaust gas inlet channel communicate with each other, the opening / closing valve is able to allow the first branch channel and the second branch channel to communicate with each other and to block the first branch channel and the second branch channel, and a communication range between the first branch channel and the second branch channel decreases and then increases as a valve opening degree increases from a time when the opening / closing valve is closed. [7] Turbocharger according to claim 1, wherein a length from a bottom surface of the opening / closing valve to a center of the communication groove is set to 0.3 times or more a length in the opening / closing direction of the opening / closing valve. [8] Turbocharger according to claim 1, wherein a length from a bottom surface of the opening / closing valve to the communication groove is set in a range of 1.0 times to 1.2 times a length from the bottom surface of the opening / closing valve to an inner surface of the communication channel on an opening direction side of the opening / closing valve.

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