Patent Application
20250198301
The present disclosure relates to a turbocharger. This application claims the benefit of priority to Japanese Patent Application No. 2022-183720 filed on Nov. 16, 2022 and contents thereof are incorporated herein.
In some turbochargers, an electric actuator such as a motor is used to drive a movable member. For example, in Patent Literature 1, there is disclosed a turbocharger including a motor for turning variable nozzle vanes that are used to adjust a flow velocity of gas to be sent to a turbine wheel.
Patent Literature 1: WO 2018/207624 A1
In the turbocharger, components such as the electric actuator are heated due to heat from a heat source. Thus, it is appropriate that components such as the electric actuator be protected from the heat from the heat source.
An object of the present disclosure is to provide a turbocharger capable of protecting components of the turbocharger from heat.
In order to solve the problem described above, according to the present disclosure, there is provided a turbocharger, including: a target component; and a heat-shielding cover, which is provided between the target component and a heat source, and includes at least one cover member that defines a heat-shielding space around the target component, at least one heat-shielding space having a thickness becoming maximum at a position on the heat source side with respect to the target component.
The cover member may include: a first cover member covering an outer surface of the target component; and a second cover member covering an outer surface of the first cover member, and the heat-shielding space may include: a first heat-shielding space defined between the outer surface of the target component and an inner surface of the first cover member; and a second heat-shielding space defined between an outer surface of the first cover member and an inner surface of the second cover member.
A thickness of the first heat-shielding space may become maximum at the position on the heat source side with respect to the target component.
A thickness of the second heat-shielding space may become maximum at the position on the heat source side with respect to the target component.
The first cover member and the second cover member may be fixed to each other.
The heat-shielding space may be formed so as to penetrate in a vertical direction.
According to the present disclosure, components of the turbocharger can be protected from heat.
Now, with reference to the attached drawings, an embodiment of the present disclosure is described. The dimensions, materials, other specific numerical values, and the like represented in the embodiment are merely examples used for facilitating the understanding of the disclosure, and do not limit the present disclosure unless otherwise particularly noted. Elements having substantially the same functions and configurations herein and in the drawings are denoted by the same reference symbols to omit redundant description thereof. Further, illustration of elements with no direct relationship to the present disclosure is omitted.
As illustrated in
The turbine wheel 20 and the compressor impeller 40 are connected to each other through intermediation of a shaft 50 that is rotatably supported by bearings in a pivotable manner. The turbine wheel 20, the compressor impeller 40, and the shaft 50 rotate integrally.
The turbocharger TC is connected to an engine. An exhaust gas discharged from the engine flows into the turbine housing 10 and rotates the turbine wheel 20. After that, the exhaust gas flows out to an outside of the turbine housing 10. A rotational force of the turbine wheel 20 is transmitted to the compressor impeller 40 via the shaft 50. Rotation of the compressor impeller 40 causes outside air to be sucked into the compressor housing 30. The sucked air is compressed and is supplied to an air intake port of the engine.
The turbine T is a variable displacement turbine. An adjustment mechanism 60 for adjusting a flow velocity of the exhaust gas to be sent to the turbine wheel 20 is provided in the turbine housing 10. The adjustment mechanism 60 includes a plurality of variable nozzle vanes 61 capable of adjusting a flow passage sectional area of a flow passage on an upstream side of the turbine wheel 20. The plurality of variable nozzle vanes 61 are arranged on a radially outer side with respect to the turbine wheel 20. The plurality of variable nozzle vanes 61 are arranged at intervals in a circumferential direction of the turbine wheel 20. Turning of the variable nozzle vanes 61 changes the flow passage sectional area in accordance with a turning angle of the variable nozzle vanes 61. As a drive source for driving such an adjustment mechanism 60, a motor 70 is provided outside the turbine housing 10 and the compressor housing 30.
The motor 70 has a substantially quadrangular prism shape. In the X-axis direction, the motor 70 is arranged between the turbine housing 10 and the compressor housing 30. The motor 70 is positioned vertically above the turbine housing 10 and the compressor housing 30, and extends in a vertical direction.
An output shaft of the motor 70 is coupled to the adjustment mechanism 60 provided in the turbine housing 10 through intermediation of various members such as a link member. A driving force output from the motor 70 turns the variable nozzle vanes 61 of the adjustment mechanism 60 to thereby change the flow passage sectional area. As a result, the flow velocity of the exhaust gas to be sent to the turbine wheel 20 is changed.
A heat-shielding cover 80 is provided between the motor 70 and a heat source so as to protect the motor 70 from heat from the heat source. In
Now, details of the heat-shielding cover 80 are described with reference to
As illustrated in
A circumferential direction of the motor 70 and a radial direction of the motor 70 are hereinafter also referred to simply as “circumferential direction” and “radial direction.” The circumferential direction of the motor 70 corresponds to a circumferential direction of the main body 71 about a center axis extending in the vertical direction. The radial direction of the motor 70 corresponds to the radial direction of the main body 71 about the center axis extending in the vertical direction.
The heat-shielding cover 80 includes a first cover member 81 and a second cover member 82. As described later, the first cover member 81 and the second cover member 82 define a first heat-shielding space 91 and a second heat-shielding space 92 around the motor 70 as a heat-shielding space. The heat-shielding space is a space for shielding heat that may be transferred to the motor 70.
The first cover member 81 covers a part of an outer peripheral surface of the motor 70. In the example of
Further, the first cover member 81 extends in the vertical direction. A length of the first cover member 81 in the vertical direction is substantially equal to a length of the motor 70 in the vertical direction. A position of an upper end of the first cover member 81 in the vertical direction is substantially the same as a position of an upper end of the motor 70 in the vertical direction. A position of a lower end of the first cover member 81 in the vertical direction is substantially the same as a position of a lower end of the motor 70 in the vertical direction.
A mounting member 83 is connected to a lower part of the first cover member 81. In the example of
The second cover member 82 covers an outer surface of the first cover member 81. A surface of the first cover member 81 on the motor 70 side is an inner surface of the first cover member 81, and a surface of the first cover member 81 on a side opposite to the motor 70 is an outer surface of the first cover member 81. The second cover member 82 extends in the circumferential direction. In the circumferential direction, a range in which the first cover member 81 is present and a range in which the second cover member 82 is present are substantially the same.
As illustrated in
Further, the second cover member 82 extends in the vertical direction. A length of the second cover member 82 in the vertical direction is substantially equal to the length of the first cover member 81 in the vertical direction. A position of an upper end of the second cover member 82 in the vertical direction is substantially the same as the position of the upper end of the first cover member 81 in the vertical direction. A position of a lower end of the second cover member 82 in the vertical direction is substantially the same as the position of the lower end of the first cover member 81 in the vertical direction.
The first heat-shielding space 91 is defined between an outer surface of the motor 70 and the inner surface of the first cover member 81. In the example of
The second heat-shielding space 92 is defined between the outer surface of the first cover member 81 and an inner surface of the second cover member 82. A surface of the second cover member 82 on the first cover member 81 side is the inner surface of the second cover member 82, and a surface of the second cover member 82 on a side opposite to the first cover member 81 is an outer surface of the second cover member 82. In the example of
In
A thickness T1 of the first heat-shielding space 91 becomes maximum at a position on the heat source side with respect to the motor 70. The thickness T1 corresponds to a distance between the outer peripheral surface of the main body 71 of the motor 70 and the inner surface of the first cover member 81. In
Meanwhile, a thickness T2 of the second heat-shielding space 92 is constant at all positions in the circumferential direction. The thickness T2 corresponds to a distance between the outer surface of the first cover member 81 and the inner surface of the second cover member 82. In
As described above, in the turbocharger TC, the thickness T1 of the first heat-shielding space 91 becomes maximum at the position on the heat source side with respect to the motor 70. In this manner, a layer of air having a low thermal conductivity can be made thick at the position in the first heat-shielding space 91 on the heat source side with respect to the motor 70 (that is, the position illustrated as the region R3). Thus, heat transferred from the first cover member 81 to the motor 70 through heat conduction can be reduced. Further, heat transferred from the first cover member 81 to the motor 70 through radiant heat transfer can be reduced at the position in the first heat-shielding space 91 on the heat source side with respect to the motor 70. Further, a flow rate of the air flowing at the position in the first heat-shielding space 91 on the heat source side with respect to the motor 70 increases, and thus a rise in temperature of the air at the position is suppressed. Accordingly, the motor 70 can be protected from heat.
Description has been given above of the example in which the first cover member 81 and the second cover member 82 are provided as the cover member that defines the heat-shielding space around the motor 70 being a target component. However, the number of cover members may be one or three or more. Further, description has been given above of the example in which the thickness T1 of the first heat-shielding space 91 becomes maximum at the position on the heat source side with respect to the motor 70. However, when a plurality of heat-shielding spaces are defined, any of the heat-shielding spaces may be the heat-shielding space that has a maximum thickness at the position on the heat source side with respect to the motor 70. For example, the thickness T2 of the second heat-shielding space 92 may become maximum at the position on the heat source side with respect to the motor 70. Further, when a plurality of heat-shielding spaces are defined, the number of heat-shielding spaces, each having a maximum thickness at the position on the heat source side with respect to the motor 70, may be one or plural.
That is, the turbocharger TC includes the target component (the motor 70 in the example described above) and the heat-shielding cover 80 provided between the target component and the heat source. It suffices that the heat-shielding cover 80 include at least one cover member (the first cover member 81 and the second cover member 82 in the example described above) that defines the heat-shielding space around the target component. Further, it suffices that a thickness of at least one heat-shielding space (the first heat-shielding space 91 in the example described above) become maximum at the position on the heat source side with respect to the target component. In this manner, heat transferred from the outside toward the target component through heat conduction and radiant heat transfer can be reduced at the position in the at least one heat-shielding space described above (the region R3 of the first heat-shielding space 91 in the example described above) on the heat source side with respect to the target component. Accordingly, the components of the turbocharger TC can be protected from heat.
In the example described above, in particular, the cover member that defines the heat-shielding space around the target component includes: the first cover member 81 that covers the outer surface of the target component (the motor 70 in the example described above); and the second cover member 82 that covers the outer surface of the first cover member 81. Further, the heat-shielding space includes: the first heat-shielding space 91 defined between the outer surface of the target component and the inner surface of the first cover member 81; and the second heat-shielding space 92 defined between the outer surface of the first cover member 81 and the inner surface of the second cover member 82. In this manner, a double-layered heat-shielding space can be provided for the target component. Thus, a heat-shielding property for the target component is improved. Accordingly, the components of the turbocharger TC can be more effectively protected from heat.
In the example described above, in particular, the first cover member 81 and the second cover member 82 are fixed to each other. As a result, when the first cover member 81 and the second cover member 82, which have been integrated with each other, are mounted to the target component (the motor 70 in the example described above), a double-layered heat-shielding space can be provided for the target component. Meanwhile, when the first cover member 81 and the second cover member 82 are not fixed to each other, it is appropriate to mount the first cover member 81 and the second cover member 82 separately to the target component. Thus, there arise problems such as an increase in the number of components (for example, bolts) for mounting the first cover member 81 and the second cover member 82 to the target component, enlargement of a tool path for a tool used for the components, and an increase in cycle time of assembly work. Thus, the fixing of the first cover member 81 and the second cover member 82 eliminates the problems described above. Further, when the first cover member 81 and the second cover member 82 are fixed to each other, stiffness of the cover members is improved in a synergetic manner.
In the example described above, in particular, the heat-shielding space (the first heat-shielding space 91 and the second heat-shielding space 92 in the example described above) is defined so as to penetrate in the vertical direction. In this manner, when, for example, the turbocharger TC is mounted in a movable object such as a vehicle, a stack effect of a traveling wind flowing in the horizontal direction, which is generated by traveling of the movable object, can induce flow of air in the vertical direction in the heat-shielding space. As a result, stagnation of the air in the heat-shielding space can be suppressed to thereby suppress a rise in temperature of the air in the heat-shielding space. Thus, a heat-shielding property for the target component is improved. Accordingly, the components of the turbocharger TC can be more effectively protected from heat.
Description has been given above with reference to
3. Otherwise, the modification examples are the same as the example of
Meanwhile, the heat-shielding cover 80A in the first modification example differs from the heat-shielding cover of the above-mentioned example of
Thus, a thickness T2 of a second heat-shielding space 92 becomes maximum at a position on the heat source side with respect to the motor 70. Specifically, as illustrated in
As described above, in the first modification example, the thickness T1 of the first heat-shielding space 91 becomes maximum at the position on the heat source side with respect to the motor 70. As a result, the same effects as those of the above-mentioned example of
Thus, a thickness T2 of a second heat-shielding space 92 becomes maximum at a position on the heat source side with respect to the motor 70. Specifically, as illustrated in
As described above, in the second modification example, the thickness T1 of the first heat-shielding space 91 becomes maximum at the position on the heat source side with respect to the motor 70, and the thickness T2 of the second heat-shielding space 92 also becomes maximum at the position on the heat source side with respect to the motor 70. As a result, the same effects as those of the above-mentioned example of
In the example of
Meanwhile, the heat-shielding cover 80C in the third modification example differs from the heat-shielding cover of the above-mentioned example of
Thus, a thickness T2 of a second heat-shielding space 92 becomes minimum at a position on the heat source side with respect to the motor 70. Specifically, as illustrated in
As described above, in the third modification example, the thickness T1 of the first heat-shielding space 91 becomes maximum at the position on the heat source side with respect to the motor 70. As a result, the same effects as those of the above-mentioned example of
An embodiment of the present disclosure has been described above with reference to the attached drawings, but, needless to say, the present disclosure is not limited to the above-mentioned embodiment. It is apparent that those skilled in the art may arrive at various alternations and modifications within the scope of claims, and those examples are construed as naturally falling within the technical scope of the present disclosure.
The present disclosure includes the following configurations.
The turbocharger of the present disclosure is [1] “a turbocharger, including: a target component; and a heat-shielding cover, which is provided between the target component and a heat source, and includes at least one cover member that defines a heat-shielding space around the target component, at least one heat-shielding space having a thickness becoming maximum at a position on the heat source side with respect to the target component.”
The turbocharger of the present disclosure may be [2] “the turbocharger according to Item [1], wherein the cover member includes: a first cover member covering an outer surface of the target component; and a second cover member covering an outer surface of the first cover member, and wherein the heat-shielding space includes: a first heat-shielding space defined between the outer surface of the target component and an inner surface of the first cover member; and a second heat-shielding space defined between an outer surface of the first cover member and an inner surface of the second cover member.”
The turbocharger of the present disclosure may be [3] “the turbocharger according to Item [2], wherein a thickness of the first heat-shielding space becomes maximum at the position on the heat source side with respect to the target component.”
The turbocharger of the present disclosure may be [4] “the turbocharger according to Item [2] or [3], wherein a thickness of the second heat-shielding space becomes maximum at the position on the heat source side with respect to the target component.”
The turbocharger of the present disclosure may be [5] “the turbocharger according to any one of Items [2] to [4], wherein the first cover member and the second cover member are fixed to each other.”
The turbocharger of the present disclosure may be [6] “the turbocharger according to any one of Items [1] to [5], wherein the heat-shielding space is formed so as to penetrate in a vertical direction.”
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-183720 | Nov 2022 | JP | national |
This application is a continuation application of International Application No. PCT/JP2023/023112, filed on Jun. 22, 2023, which claims priority to Japanese Patent Application No. 2022-183720, filed on Nov. 16, 2022, the entire contents of which are incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2023/023112 | Jun 2023 | WO |
| Child | 19071844 | US |
