JP4779898B2 - Turbine housing - Google Patents

Description

  The present invention relates to a turbine housing used in a turbocharger that generates supercharging pressure for an internal combustion engine using the energy of exhaust gas of the internal combustion engine, and more specifically, a so-called double pipe having an outer shell and an inner shell. The present invention relates to a turbine housing having a simple structure that can contribute to downsizing and improvement in turbine efficiency and can improve heat resistance.

  2. Description of the Related Art Conventionally, a turbocharger that improves the output of an internal combustion engine by supplying pressurized air into an intake manifold using exhaust gas discharged from the internal combustion engine as a drive source is known.

  When this turbocharger is used by being mounted on an in-vehicle internal combustion engine, it is necessary to consider weight reduction. In recent years, in particular, from the viewpoint of improving fuel efficiency and athletic performance, it is required to reduce the weight of vehicle-mounted components, and the above-described conventional turbocharger has also been reduced as much as possible.

  Therefore, in recent years, a turbine housing made of sheet metal (thin metal) has been used instead of the conventional cast turbine housing. This is because the sheet metal turbine housing can be easily manufactured as compared with the cast turbine housing, and is advantageous in that the weight is reduced.

  Further, since the turbine housing is directly exposed to high-temperature exhaust gas and is greatly affected by thermal deformation, sufficient consideration is required for heat resistance.

  As a conventional turbine housing composed of such sheet metal piping, for example, those shown in FIGS. 8 and 9 are known. Here, FIG. 8 is a front view showing a conventional turbine housing, and FIG. 9 is a rear view showing the conventional turbine housing.

  As shown in FIGS. 8 and 9, the conventional turbine housing 10 includes a spiral exhaust gas by an inner pipe 2a partially indicated by a broken line and an outer pipe 2b encapsulating the inner pipe 2a with a gap. The scroll part 2 comprised as a channel | path, and the bypass passage exit opening part 5b which bypasses the inside of the inner tube | pipe 2a (scroll part 2) and the external exhaust gas passage which is not shown in figure are provided.

  The inner tube 2a and the outer tube 2b are formed of a metal excellent in heat resistance and corrosion resistance, for example, a press-formed product of stainless steel.

  The turbine housing 10 includes a turbine inlet flange 3 connected to an exhaust gas passage such as an exhaust manifold (not shown), a turbine outlet flange 4 connected to a compressor housing side (not shown), and a turbine passage inlet opening for introducing exhaust gas. A portion 6a and a turbine passage outlet opening 6b for discharging exhaust gas.

  That is, exhaust gas that has flowed through an exhaust gas passage such as an exhaust manifold (not shown) flows through the inner pipe 2a as the turbine passage 6 from the turbine passage inlet opening 6a, rotates the turbine (not shown), and then opens the turbine passage outlet. It is discharged from the part 6b to the outside.

  Further, the bypass passage outlet opening 5b functions as a so-called waste gate port, and when the flow rate of the exhaust gas in the scroll portion 2 is excessive, it is opened by a waste gate valve (not shown), Conversely, when the flow rate of the exhaust gas is not excessive, it is blocked by the wastegate valve. By such control of the waste gate valve, the flow rate of the exhaust gas flowing through the scroll portion 2 is set to be maintained in a good state.

  In addition, as a related prior art, a double pipe turbine housing in which a bypass passage to a waste gate valve is configured by a dedicated inner pipe has been proposed (for example, see Patent Document 1).

  Further, there has been proposed one in which an opening portion of an inner tube of a double tube and a through hole of a metal mating member provided with an outer tube are communicated to form an exhaust gas bypass passage (for example, , See Patent Document 2).

  In addition, a turbine housing is proposed in which both the inner shell and the outer shell are made of a heat-resistant steel plate press-formed product (see, for example, Patent Document 3).

JP 2004-183651 A JP 2001-303963 A JP 2003-293780 A

  However, in the case of a conventional turbine housing made of cast, it is necessary to provide the position of the wastegate port, which is the bypass passage outlet opening, in the turbine passage of the turbine housing. Because of branching by the port, there is a problem that the flow is disturbed and the turbine efficiency is lowered.

  In addition, the turbine housing made of sheet metal has a problem that it is difficult to manufacture because the structure of the branch portion of the wastegate port is complicated.

  Further, in the double-pipe sheet metal turbine housing 10 composed of the inner pipe 2a and the outer pipe 2b, when the stress is applied to the inner pipe 2a due to a temperature difference between the inner pipe 2a and the outer pipe 2b, a bypass having a small pipe diameter is provided. There is also a problem that it is difficult to secure the strength of the portion because stress concentrates on the passage outlet opening (waist gate port portion) 5b.

  The present invention has been made in view of the above, and it is an object of the present invention to provide a turbine housing having a simple structure that can contribute to miniaturization and improvement in turbine efficiency and can improve heat resistance. To do.

In order to solve the above-described problems and achieve the object, a turbine housing according to a first aspect of the present invention includes a spiral exhaust including at least an inner tube and an outer tube encapsulating the inner tube with a gap. A scroll portion configured as a gas passage, and a waist gate port flange connecting the gap and an external exhaust gas passage outside the outer pipe or a seat member provided on the waist gate port flange, In a turbine housing comprising a bypass passage outlet opening that bypasses the inside of the scroll portion and the external exhaust gas passage, the gap between the inner pipe and the outer pipe is formed in the bypass passage outlet opening. It is characterized by comprising as a bypass passage that leads to.

  A turbine housing according to a second aspect of the present invention is the turbine housing according to the first aspect, wherein an inlet opening of the bypass passage and an inlet opening of the turbine passage provided in a turbine inlet flange of the turbine housing. The partition wall for partitioning is constituted only by the inner tube.

A turbine housing according to a third aspect of the present invention is the turbine housing according to the first aspect , wherein when the bypass passage outlet opening is formed in the seat member, the end of the inner pipe is While being fitted into an opening provided in a turbine inlet flange of the turbine housing, an end portion of the outer pipe is welded and fixed to the turbine inlet flange.

A turbine housing according to a fourth aspect of the present invention is the turbine housing according to the first or second aspect, wherein the bypass passage outlet opening is formed when the bypass passage outlet opening is formed in the waist gate port flange. The end portion of the outer tube is welded in the vicinity of the outer peripheral edge of the portion.

  According to the turbine housing of the present invention (Claim 1), the position of the bypass passage outlet opening can be set with a simple structure without being restricted by the position of the turbine passage. This can contribute to downsizing of the turbine housing.

  Further, according to the turbine housing according to the present invention (Claim 2), since the partition wall can be constituted by the thin plate thickness of the inner pipe, it is possible to suppress the turbulence of the flow caused by the exhaust gas colliding with the partition wall. The turbine efficiency can be improved.

  Further, according to the turbine housing according to the present invention (Claim 3), the inner pipe fitted into the opening is freely expanded, thereby suppressing the concentration of thermal stress caused by the difference in thermal expansion between the inner pipe and the outer pipe. And the heat resistance strength can be improved.

  Further, according to the turbine housing according to the present invention (Claim 4), the adjustment member required for connecting the end portion of the outer pipe to the inner peripheral edge portion of the bypass passage outlet opening having a smaller diameter is unnecessary. Thus, since the end shape of the outer tube can be simplified, the manufacture becomes easy and the concentration of thermal stress can be suppressed.

  Embodiments of a turbine housing according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  1 is a front view showing a turbine housing according to Embodiment 1 of the present invention, FIG. 2 is a rear view showing the turbine housing, FIG. 3 is a cross-sectional view showing a cross section AA in FIG. 1, and FIG. It is a front view which shows a turbine inlet flange. In the following description, members that are the same as or correspond to those already described are denoted by the same reference numerals, and redundant description is omitted or simplified.

  As shown in FIGS. 1-4, the scroll part 2 used as an exhaust gas passage is comprised in the spiral form by the inner tube 2a and the outer tube 2b which encapsulated this inner tube 2a in the state with a clearance gap. . In the drawing, the inner tube 2a is appropriately partially indicated by a broken line.

  The gap between the inner tube 2a and the outer tube 2b can be formed by a known technique, for example, by appropriately interposing a spacer (not shown) between the inner tube 2a and the outer tube 2b.

  Further, the turbine inlet flange 3 is provided with a turbine passage inlet opening 6a and a bypass passage inlet opening 5a, and a partition partitioning these inlet openings 5a and 6a is composed of only the inner pipe 2a.

  The turbine outlet flange 4 is provided with a turbine passage outlet opening 6b and a bypass passage outlet opening 5b.

  The inner pipe 2a is configured as a turbine passage 6 extending from the turbine passage inlet opening 6a to the turbine passage outlet opening 6b. One end of the inner pipe 2a is inserted through the opening of the turbine inlet flange 3 and welded.

  Further, the gap between the inner pipe 2a and the outer pipe 2b is configured as a bypass passage 5 extending from the bypass passage inlet opening 5a to the bypass passage outlet opening 5b. One end of the outer tube 2b is welded to the turbine inlet flange 3.

  Further, the vicinity of the bypass passage outlet opening 5b has a structure as shown in FIG. 3, for example. That is, the bypass passage outlet opening 5b as a wastegate port is formed as an opening of the seat surface member 5c provided in the wastegate port flange 5d. The exhaust gas flowing through the bypass passage outlet opening 5 b is adjusted by opening / closing control of the waste gate valve 7.

  Further, as shown in FIG. 3, the adjusting member 2c, which is a part of the outer tube 2b, has an end portion of the outer tube 2b that has a smaller diameter bypass passage outlet opening 5b (inside the opening of the seat member 5c). For welding to the periphery).

  As described above, in the turbine housing 10 according to the prior art (see FIGS. 8 and 9), the bypass passage outlet opening 5b is provided so as to communicate with a part of the inner tube 2a. The arrangement positions of the passage outlet opening 5b are restricted by design.

  On the other hand, according to the turbine housing 1 according to the first embodiment, since the gap between the inner pipe 2a and the outer pipe 2b is configured as the bypass passage 5, the position of the turbine passage 6, that is, the position of the inner pipe 2a. The position of the bypass passage outlet opening 5b can be set without being restricted by the above. Therefore, the structure can be simplified and the degree of freedom in design can be expanded, contributing to the downsizing of the turbine housing 1.

  Moreover, since the partition which divides the bypass passage inlet opening 5a and the turbine passage inlet opening 6a can be constituted by the thin plate thickness of the inner pipe 2a, the disturbance of the flow caused by the collision of the exhaust gas with the partition is suppressed. Turbine efficiency can be improved.

  FIG. 5 is a front view showing a turbine housing 1 according to Embodiment 2 of the present invention, and FIG. 6 is a front view showing a turbine inlet flange 3.

  As shown in FIGS. 5 and 6, in the second embodiment, the end of the inner pipe 2 a is fitted into the turbine passage inlet opening 6 a provided in the turbine inlet flange 3, while the end of the outer pipe 2 b is connected to the turbine. It is constructed by welding and fixing to the inlet flange 3.

  That is, the end of the inner pipe 2a is not welded to the turbine inlet flange 3, and when the inner pipe 2a expands or contracts due to the heat action of the exhaust gas, the end of the inner pipe 2a becomes the turbine passage inlet opening. It is configured to be slidable within 6a.

  Further, the bypass passage inlet opening 5 a is formed in the turbine inlet flange 3. Other configurations are the same as the configuration of the first embodiment, and thus the redundant description is omitted.

  As described above, according to the turbine housing 1 according to the second embodiment, the inner pipe 2a fitted into the turbine passage inlet opening 6a is freely expanded, so that a difference in thermal expansion between the inner pipe 2a and the outer pipe 2b. The thermal stress concentration caused by the above can be suppressed, and the heat resistance strength can be improved.

  FIG. 7 is a cross-sectional view showing the vicinity of the turbine inlet flange 3 of the turbine housing according to the third embodiment of the present invention, and corresponds to the AA cross section of FIG.

  In the third embodiment, the end of the outer pipe 2b is welded in the vicinity of the outer peripheral edge of the bypass passage outlet opening 5b formed in the wastegate port flange 5d. Reference numeral 8 in the drawing indicates a welded portion of the outer tube 2b. Other configurations are the same as the configuration of the first embodiment, and thus the redundant description is omitted.

  As described above, according to the turbine housing according to the third embodiment, the end of the outer pipe 2b is connected to the inner peripheral edge of the bypass passage outlet opening 5b having a smaller diameter (the inner peripheral edge of the opening of the seat member 5c). The adjustment member 2c (see FIG. 3) that is necessary for connecting to the outer tube 2b is not necessary, and the end shape of the outer tube 2b can be simplified, facilitating manufacturing and suppressing the concentration of thermal stress. be able to.

  As described above, the turbine housing according to the present invention is useful for a sheet metal turbine housing having a double-pipe structure employed in a turbocharger for an internal combustion engine. In particular, the simple structure reduces the size and improves the turbine efficiency. It is suitable for turbine housings that can contribute and improve heat resistance.

It is a front view which shows the turbine housing which concerns on Example 1 of this invention. It is a rear view which shows a turbine housing. It is sectional drawing which shows the AA cross section of FIG. It is a front view which shows a turbine inlet flange. It is a front view which shows the turbine housing which concerns on Example 2 of this invention. It is a front view which shows a turbine inlet flange. It is sectional drawing which shows the turbine inlet flange vicinity of the turbine housing which concerns on Example 3 of this invention. It is a front view which shows the conventional turbine housing. It is a rear view which shows the conventional turbine housing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Turbine housing 2 Scroll part 2a Inner pipe 2b Outer pipe 2c Adjustment member 3 Turbine inlet flange 4 Turbine outlet flange 5 Bypass passage 5a Bypass passage inlet opening 5b Bypass passage outlet opening 5c Seat surface member 5d West gate port flange 6 Turbine passage 6a Turbine passage inlet opening 6b Turbine passage outlet opening 7 Wastegate valve 8 Welded portion

Claims (4)

At least a scroll portion configured as a spiral exhaust gas passage by an inner tube and an outer tube encapsulating the inner tube with a gap;
A waste gate port flange that connects the gap and an external exhaust gas passage outside the outer pipe or a seat member provided on the waste gate port flange, and the exhaust gas inside and outside the scroll portion. A bypass passage outlet opening for bypassing the passage;
In a turbine housing with
A turbine housing characterized in that the gap between the inner pipe and the outer pipe is configured as a bypass passage leading to the bypass passage outlet opening.   The partition which partitions the inlet opening part of the bypass passage provided in the turbine inlet flange of the turbine housing and the inlet opening part of the turbine passage is constituted only by the inner pipe. Turbine housing. When the bypass passage outlet opening is formed in the seat member, the end of the inner pipe is fitted into the opening provided in the turbine inlet flange of the turbine housing, while the end of the outer pipe The turbine housing according to claim 1, wherein a turbine is fixed to the turbine inlet flange by welding. The end portion of the outer pipe is welded in the vicinity of the outer peripheral edge of the bypass passage outlet opening when the bypass passage outlet opening is formed in the wastegate port flange. A turbine housing according to claim 1.

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