JP4548237B2 - Turbocharger twin scroll turbine housing - Google Patents

Description

  The present invention relates to a turbine housing of a turbocharger installed in a vehicle, and more particularly to a structure of a twin scroll turbine housing having two scroll passages.

  Conventionally known as a turbocharger turbine housing mounted on a vehicle is a twin scroll turbine housing that avoids engine exhaust interference and effectively utilizes the exhaust pulse effect to increase the rotational efficiency of the turbine rotor. .

This type of twin scroll turbine housing is provided with two scroll passages as exhaust passages surrounding the turbine rotor (see, for example, Patent Document 1), and exhaust gas discharged at different timings flows. Each scroll flow path is communicated with two waste gate ports opened on the seat surface of the valve seat on which the waste gate valve is seated.
JP-A-5-156958 (paragraph number 8, paragraph number 11, paragraph number 12, FIG. 1)

  By the way, as can be seen from Patent Document 1, in this type of twin scroll turbine housing, two waste gate ports communicating with two scroll flow paths having different exhaust timings are usually provided as valve seats of waste gate valves. Are simply arranged side by side at symmetrical positions on the sheet surface. For this reason, in the waste gate valve, the exhaust pulsation pressure from the two waste gate ports alternately acts on the symmetric position of the valve surface, and the accompanying moment acts on the waste gate valve.

  Here, in order to improve the seating property with respect to the valve seat, a general waste gate valve is usually provided with a support point at the center. When such a waste gate valve is closed, the waste gate valve vibrates minutely due to the moment acting on it, so noise is generated and the degree of adhesion of the waste gate valve to the valve seat is reduced, resulting in the rotational efficiency of the turbine rotor. May decrease. In addition, when the waste gate valve is opened, the waste gate valve vibrates greatly due to the moment acting on the waste gate valve, and wear or fatigue failure occurs at the support point of the waste gate valve, resulting in durability of the waste gate valve. May be reduced.

  Accordingly, an object of the present invention is to provide a structure capable of improving the performance and durability of a waste gate valve in a twin scroll turbine housing of a turbocharger.

  A twin scroll turbine housing of a turbocharger according to the present invention is a turbine housing that houses a turbine rotor of a turbocharger, and includes first and second scroll channels surrounding the turbine rotor, and each scroll channel. First and second waste gate ports that communicate with each other and open to the seat surface of the valve seat, and a single waste gate valve that seats on the valve seat so that the respective waste gate ports can be opened simultaneously are provided. Of the two waste gate ports, one waste gate port opens in the center of the seat surface of the valve seat, and the other waste gate port opens concentrically around one waste gate port. To do.

  In the turbocharger twin scroll turbine housing according to the present invention, the exhaust pulsation pressure from one waste gate port and the exhaust pulsation pressure from the other waste gate port are concentric with the central portion of the valve surface of the waste gate valve and its surroundings. Therefore, an unnecessary moment does not act on the waste gate valve. As a result, minute vibrations when the waste gate valve is closed are suppressed, the degree of adhesion of the waste gate valve to the valve seat is improved, and vibration noise is prevented. In addition, large vibrations when the waste gate valve is opened are suppressed, and wear and fatigue failure of the support point of the waste gate valve are suppressed.

  A twin scroll turbine housing of a turbocharger according to the present invention is a turbine housing that houses a turbine rotor of a turbocharger, and includes first and second scroll channels surrounding the turbine rotor, and each scroll channel. A first waste gate port that opens to the seat surface of the valve seat, and a single waste gate valve that sits on the valve seat so that each waste gate port can be opened simultaneously. One waste gate port of the first and second waste gate ports is opened at the center of the seat surface of the valve seat, and the other waste gate port is opened symmetrically on both sides of the one waste gate port. It is characterized by.

  In the twin scroll turbine housing of the turbocharger according to the present invention, the exhaust pulsation pressure from one waste gate port and the exhaust pulsation pressure from the other waste gate port are symmetrical with respect to the central portion of the valve surface of the waste gate valve and both sides thereof. Therefore, an unnecessary moment does not act on the waste gate valve. As a result, minute vibrations when the waste gate valve is closed are suppressed, the degree of adhesion of the waste gate valve to the valve seat is improved, and vibration noise is prevented. In addition, large vibrations when the waste gate valve is opened are suppressed, and wear and fatigue failure of the support point of the waste gate valve are suppressed.

  According to the twin scroll turbine housing of the turbocharger according to the present invention, an unnecessary moment does not act on the waste gate valve, so that minute vibrations when the waste gate valve is closed are suppressed, and the degree of adhesion of the waste gate valve to the valve seat. Is improved and vibration noise is prevented. In addition, large vibrations when the waste gate valve is opened are suppressed, and wear and fatigue failure of the support point of the waste gate valve are suppressed. Therefore, the performance and durability of the waste gate valve can be improved.

  Embodiments of a twin scroll turbine housing for a turbocharger according to the present invention will be described below with reference to the drawings. In the drawings to be referred to, FIG. 1 is a front view of a turbocharger as viewed from the outlet flange side of the twin scroll turbine housing according to the first embodiment, and FIG. 2 is a sectional view taken along line II-II in FIG.

  The twin scroll turbine housing of the turbocharger according to the first embodiment is a turbine rotor that rotates by circulation of exhaust gas in a turbocharger (for example, see FIG. 1) installed across an exhaust system and an intake system of a vehicle (not shown). (See FIG. 2).

  As shown in FIGS. 1 and 2, the twin scroll turbine housing 1 of the first embodiment includes an inlet flange 2 having two exhaust gas inlets with different exhaust timings, and an exhaust gas outlet integrated into one system. Between the two exhaust gas inlets on the inlet flange 2 side and the one exhaust gas outlet on the outlet flange 3 side around the turbine rotor 4. The turbine scroll part 5 which forms the 2 scroll flow path 5B, and the connection flange 7 connected to the bearing housing 6 which supports the turbine rotor 4 rotatably are provided.

  Here, as shown in FIG. 1, a waste gate valve device 8 is provided in the vicinity of the outlet flange 3 of the twin scroll turbine housing 1 to keep the turbocharger supercharging pressure below a set value. This waste gate valve device 8 includes a single waste gate valve 8A for allowing a part of the exhaust gas to escape from the first scroll channel 5A and the second scroll channel 5B (see FIG. 2) to the exhaust gas outlet, An actuator 8B for opening and closing the waste gate valve 8A, and a lever 8C, a waste gate pin 8D, and an operation arm 8E that constitute a link mechanism so as to open and close the waste gate valve 8A according to the operation of the actuator 8B are provided. .

  The actuator 8B is disposed outside the outlet flange 3. The actuator 8B has an operating rod 8F that contracts when the turbocharger supercharging pressure is equal to or lower than a set value and expands when the turbocharger exceeds the set value. The proximal end of the lever 8C is pivotally attached to the distal end of the operating rod 8F, and the distal end of the lever 8C penetrates the wall of the outlet flange 3 and rotates around the axis of the waste gate pin 8D. It is fixed to the outer end. The proximal end portion of the operation arm 8E is fixed to the inner end portion of the waste gate pin 8D facing the inside of the outlet flange 3. The distal end of the operation arm 8E is formed in a fork shape, for example.

  The waste gate valve 8A is formed in a disc shape in which a support pin 8A1 sandwiched between the fork-shaped tip portions of the operation arm 8E is projected from the center portion (see FIG. 2). An engaging head 8A2 that engages with the fork-shaped tip of the operating arm 8E is formed at the tip of the support pin 8A1 of the waste gate valve 8A.

  On the other hand, as shown in FIG. 2, a valve seat portion 9 on which a waste gate valve 8 </ b> A is seated is formed inside the outlet flange 3 of the twin scroll turbine housing 1. A disc-shaped waste gate valve 8A, the center of which is supported at the tip of the operation arm 8E via a support pin 8A1, can be seated with the valve surface 8A3 facing the circular seat surface 9A of the valve seat portion 9. Is arranged.

  Here, as shown in FIG. 3, the first waste gate port 9B and the second waste gate port 9C are opened on the seat surface 9A of the valve seat portion 9 shown in FIG. The second waste gate port 9C opens in a circular shape at the center of the seat surface 9A of the valve seat portion 9, and the first waste gate port 9B opens concentrically around the second waste gate port 9C.

  The second waste gate port 9C communicates with the second scroll passage 5B of the turbine scroll portion 5 shown in FIG. 2 via the second bypass passage 5D, and the first waste gate port 9B is connected to the first scroll passage 9B. 5A communicates with the first bypass passage 5C.

  In the turbocharger including the twin scroll turbine housing 1 of the first embodiment configured as described above, the exhaust gas differs between the first scroll flow path 5A and the second scroll flow path 5B in accordance with the operation of the engine (not shown). By distributing at the timing, the engine performance is improved because there is no exhaust interference between the cylinders of the engine. Further, the turbine rotor 4 rotates efficiently by effectively utilizing the exhaust pulse effect without being subjected to exhaust interference.

  Here, when the supercharging pressure of the turbocharger is equal to or lower than the set value, the operating rod 8F of the actuator 8B is contracted, so that the operating rod 8F is linked via the lever 8C, the waste gate pin 8D, and the operating arm 8E. The single waste gate valve 8A is seated on the seat surface 9A of the valve seat portion 9 and simultaneously closes the first waste gate port 9B and the second waste gate port 9C.

  In this case, exhaust pulsation pressure acts alternately on the valve surface 8A3 of the waste gate valve 8A at different exhaust timings from the first waste gate port 9B and the second waste gate port 9C. However, the exhaust pulsation pressure from the second waste gate port 9C acts on the central portion of the valve surface 8A3 of the waste gate valve 8A, and the exhaust pulsation pressure from the first waste gate port 9B is concentric in the central portion of the valve surface 8A3. Acts on the area surrounded by For this reason, an unnecessary moment due to exhaust pulsation pressure acting at different exhaust timings does not occur in the waste gate valve 8A in which the support pin 8A1 as a support point protrudes from the center.

  As a result, minute vibrations when the waste gate valve 8A is closed are suppressed, vibration noise of the waste gate valve 8A is prevented, and the valve surface 8A3 of the waste gate valve 8A with respect to the seat surface 9A of the valve seat portion 9 is prevented. The degree of adhesion improves. Therefore, according to the structure of the twin scroll turbine housing 1 of the first embodiment, the performance of the waste gate valve 8A can be improved.

  On the other hand, when the supercharging pressure of the turbocharger rises above a set value, the operating rod 8F of the actuator 8B extends, and therefore, a single waste gate valve 8A linked to the operating rod 8F becomes the seat of the valve seat portion 9. The first waste gate port 9B and the second waste gate port 9C are simultaneously opened apart from the surface 9A.

  As a result, a part of the exhaust gas flowing through the first scroll passage 5A is released from the first bypass passage 5C to the exhaust gas outlet inside the outlet flange 3 through the first waste gate port 9B, and the second Part of the exhaust gas flowing through the scroll flow path 5B is allowed to escape from the second bypass passage 5D to the exhaust gas outlet inside the outlet flange 3 via the second waste gate port 9C. Supply pressure is kept below the set value.

  Here, even when the turbocharger supercharging pressure rises above a set value and the waste gate valve 8A opens away from the seat surface 9A of the valve seat portion 9, the exhaust pulsation pressure from the second waste gate port 9C is also obtained. Acts on the central portion of the valve surface 8A3 of the waste gate valve 8A, and the exhaust pulsation pressure from the first waste gate port 9B acts on a portion concentrically surrounding the central portion of the valve surface 8A3. For this reason, unnecessary moment due to exhaust pulsation pressure acting at different exhaust timings does not occur in the waste gate valve 8A.

  As a result, a large vibration when the waste gate valve 8A is opened is suppressed, and wear and fatigue destruction of the support pin 8A1, the engagement head 8A2, and the tip of the operation arm 8E of the waste gate valve 8A are suppressed. Therefore, according to the structure of the twin scroll turbine housing 1 of the first embodiment, it is possible to improve the durability of the waste gate valve 8A.

  Next, a twin scroll turbine housing according to a second embodiment of the present invention will be described with reference to FIGS. 4 and 5. As shown in FIG. 4, the twin scroll turbine housing 10 according to the second embodiment includes a valve seat portion 19 corresponding to the valve seat portion 9 of the twin scroll turbine housing 1 of the first embodiment shown in FIG. The structure of the related part is changed, and the other structural parts are configured in substantially the same manner as the twin scroll turbine housing 1 shown in FIG. A detailed description is omitted with reference numerals.

  Here, as shown in FIG. 5, the first waste gate port 19B and the second waste gate ports 19C and 19C are opened on the seat surface 19A of the valve seat portion 19 shown in FIG. The first waste gate port 19B opens in an elongated rectangular shape along the center line of the circular seat surface 19A, and the second waste gate ports 19C and 19C are semicircular on both sides of the first waste gate port 19B. It opens in a narrow crescent-like symmetrical shape.

  The first waste gate port 19B communicates with the first scroll passage 15A of the turbine scroll portion 15 shown in FIG. 4 via the first bypass passage 15C, and the pair of second waste gate ports 19C and 19C are connected to the second scroll passage. The flow path 15B communicates with the second bypass path 15D.

  In the twin scroll turbine housing 10 of the second embodiment provided with the valve seat portion 19 having such a structure, a single waste gate valve 8A is seated on the seat surface 19A of the valve seat portion 19 and the first waste gate port 19B. When the waste gate valve 19C is closed at the same time, and when the waste gate valve 8A is opened away from the seat surface 19A from this state, the valve surface 8A3 of the waste gate valve 8A has a first surface. Exhaust pulsation pressure from the first waste gate port 19B acts on the central portion facing the waste gate port 19B, and the crescent-shaped symmetrical portions on both sides of the central portion facing the second waste gate ports 19C and 19C Exhaust pulse from 2 waste gate ports 19C, 19C Pressure is applied at the same time.

  For this reason, also in the twin scroll turbine housing 10 of the second embodiment, an unnecessary moment due to exhaust pulsation pressure acting at different exhaust timings does not occur in the waste gate valve 8A. As a result, minute vibration when the waste gate valve 8A is closed is suppressed, vibration noise of the waste gate valve 8A is prevented, and the degree of adhesion of the valve surface 8A3 of the waste gate valve 8A to the seat surface 9A of the valve seat portion 9 is prevented. Will improve. In addition, a large vibration when the waste gate valve 8A is opened is suppressed, and wear and fatigue destruction of the support pin 8A1, the engagement head 8A2, and the tip of the operation arm 8E of the waste gate valve 8A are suppressed.

  Therefore, also in the twin scroll turbine housing 10 of the second embodiment, the performance and durability of the waste gate valve 8A can be improved as in the twin scroll turbine housing 1 of the first embodiment.

  The twin scroll turbine housing of the present invention is not limited to the above-described embodiments. For example, as shown in FIG. 6, the valve seat portion 9 shown in FIG. 3 has two first waste gate ports 9B on both sides of the center line of the seat surface 9A by the partition wall 9D formed on the center line of the seat surface 9A. You may change into the structure separated into one.

  1 and 2 is not limited to the fork shape shown in the figure, but may be formed in a ring shape through which the support pin 8A1 of the waste gate valve 8A passes.

It is a front view of the turbocharger seen from the exit flange side of the twin scroll turbine housing concerning a 1st embodiment of the present invention. It is a fragmentary sectional view which follows the II-II line of FIG. It is a front view of the valve seat part shown in Drawing 2 of the twin scroll turbine housing concerning a 1st embodiment. It is a fragmentary sectional view corresponding to FIG. 2 of the twin scroll turbine housing which concerns on 2nd Embodiment. It is a front view of the valve seat part shown in Drawing 4 of the twin scroll turbine housing concerning a 2nd embodiment. It is a front view corresponding to FIG. 3 which shows the modification of the valve seat part shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Twin scroll turbine housing 2 Inlet flange 3 Outlet flange 4 Turbine rotor 5 Turbine scroll part 5A 1st scroll flow path 5B 2nd scroll flow path 5C 1st bypass passage 5D 2nd bypass passage 8 Waste gate valve apparatus 8A Waste gate valve 8A1 Support pin 8A2 Engagement head 8A3 Valve surface 8B Actuator 9 Valve seat portion 9A Seat surface 9B First waste gate port 9C Second waste gate port 10 Twin scroll turbine housing 15 Turbine scroll portion 15A First scroll flow path 15B Second scroll Flow path 15C First bypass passage 15D Second bypass passage 19 Valve seat portion 19A Seat surface 19B First waste gate port 19C Second waste gate port Door

Claims (2)

  A turbine housing that houses a turbine rotor of a turbocharger, the first and second scroll passages surrounding the periphery of the turbine rotor, and a first opening that communicates with each scroll passage and opens to a seat surface of a valve seat. A second wastegate port and a single wastegate valve seated on the valve seat so that each wastegate port can be opened simultaneously, and one of the first and second wastegate ports Is a twin-scroll turbine housing for a turbocharger, having an opening at the center of the seat surface of the valve seat, and the other waste gate port opening concentrically around one waste gate port. A turbine housing that houses a turbine rotor of a turbocharger, the first and second scroll passages surrounding the periphery of the turbine rotor, and a first opening that communicates with each scroll passage and opens to a seat surface of a valve seat. A second wastegate port and a single wastegate valve seated on the valve seat so that each wastegate port can be opened simultaneously, and one of the first and second wastegate ports The turbocharger twin-scroll turbine housing is characterized in that is opened in the center of the seat surface of the valve seat and the other waste gate port is opened symmetrically on both sides of one waste gate port.

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