Nozzle device and exhaust turbocharger
阅读说明：本技术 喷嘴装置以及排气涡轮增压器 (Nozzle device and exhaust turbocharger ) 是由 坂本庆吾 加藤永护 樱井刚 佐久间茂吉 段本洋辅 秋山洋二 于 2019-03-28 设计创作，主要内容包括：几个实施方式的喷嘴装置具备：环形的喷嘴板；环形的喷嘴装配部,所述喷嘴装配部在与所述喷嘴板的一面之间划定喷嘴流路；至少一个喷嘴支承件,所述喷嘴支承件连结所述喷嘴板及所述喷嘴装配部,并且至少铆接固定于所述喷嘴板；以及至少一个喷嘴叶片,所述喷嘴叶片支承在所述喷嘴板与所述喷嘴装配部之间,所述喷嘴板具有供所述至少一个喷嘴支承件的端部插入的贯通孔,所述贯通孔包括：直线部,所述直线部从所述喷嘴板的所述一面朝向另一面延伸；扩径部,所述扩径部形成在所述喷嘴板的所述另一面侧,且具有比所述直线部大的直径；以及退避加工部,所述退避加工部形成于与所述扩径部相连的所述直线部的一部分,具有比未形成所述退避加工部的所述直线部的其他部分大的直径。(A nozzle device of some embodiments comprises: an annular nozzle plate; an annular nozzle mounting portion that defines a nozzle flow path between the nozzle mounting portion and one surface of the nozzle plate; at least one nozzle support member that joins the nozzle plate and the nozzle mounting portion and is riveted to at least the nozzle plate; and at least one nozzle vane supported between the nozzle plate and the nozzle mounting portion, the nozzle plate having a through-hole into which an end of the at least one nozzle support is inserted, the through-hole including: a linear portion extending from the one surface of the nozzle plate toward the other surface; an enlarged diameter portion formed on the other surface side of the nozzle plate and having a diameter larger than that of the linear portion; and a retreat processing portion formed in a part of the linear portion connected to the diameter-enlarged portion and having a diameter larger than that of the other part of the linear portion where the retreat processing portion is not formed.)
1. A nozzle device, characterized in that the nozzle device comprises:
an annular nozzle plate;
an annular nozzle mounting portion that defines a nozzle flow path between the nozzle mounting portion and one surface of the nozzle plate;
at least one nozzle support member that joins the nozzle plate and the nozzle mounting portion and is riveted to at least the nozzle plate; and
at least one nozzle vane supported between the nozzle plate and the nozzle fitting,
the nozzle plate has a through-hole into which an end of the at least one nozzle support is inserted,
the through-hole includes:
a linear portion extending from the one surface of the nozzle plate toward the other surface;
an enlarged diameter portion formed on the other surface side of the nozzle plate and having a diameter larger than that of the linear portion; and
and a retreating processing portion formed in a part of the linear portion connected to the diameter-enlarged portion and having a diameter larger than that of the other part of the linear portion where the retreating processing portion is not formed.
2. The nozzle arrangement of claim 1,
the distance between the center of the through hole on the radially inner side of the nozzle plate and the surface on which the relief processing portion is formed is larger than the distance between the center of the through hole on the radially outer side of the nozzle plate and the surface on which the relief processing portion is formed.
3. The nozzle arrangement of claim 2,
the center of the retreat processing portion is located at a position shifted inward in the radial direction of the nozzle plate with respect to the center of the through hole.
4. A nozzle device according to any one of claims 1 to 3,
at the outer diameter of the nozzle support part of A1The inner diameter of the retreating processing part is A2While the inner diameter A2Is 1.1 XA1Above and 1.5 XA1The following.
5. A nozzle device, characterized in that the nozzle device comprises:
an annular nozzle plate;
an annular nozzle mounting portion that defines a nozzle flow path between the nozzle mounting portion and one surface of the nozzle plate;
at least one nozzle support member that joins the nozzle plate and the nozzle mounting portion and is riveted to at least the nozzle plate; and
at least one nozzle vane supported between the nozzle plate and the nozzle fitting,
the nozzle plate has a through-hole into which an end of the at least one nozzle support is inserted,
the through-hole includes:
a linear portion extending from the one surface of the nozzle plate toward the other surface; and
an enlarged diameter portion formed on the other surface side of the nozzle plate and having a diameter larger than that of the linear portion,
the at least one nozzle support comprises:
a caulking portion that abuts against a surface on which the diameter-expanded portion is formed; and
and a non-caulking portion provided with a gap between a surface forming a part of the straight portion continuous to the diameter-enlarged portion and the non-caulking portion.
6. A nozzle device according to any one of claims 1 to 5,
the surface forming the diameter-expanded portion is tapered.
7. A nozzle device according to any one of claims 1 to 6,
the nozzle fitting part is fixed to the bearing housing,
the nozzle plate is supported by the nozzle mounting portion via the nozzle support.
8. A nozzle device according to any one of claims 1 to 7,
the nozzle plate has a coefficient of thermal expansion greater than that of the nozzle support.
9. An exhaust gas turbocharger comprising the nozzle device according to any one of claims 1 to 8.
Technical Field
The present disclosure relates to a nozzle device and an exhaust turbocharger provided with the nozzle device.
Background
The exhaust turbocharger supercharges air supplied to an engine by using energy of exhaust gas discharged from the engine. Conventionally, exhaust turbochargers are used in, for example, diesel engines for vehicles, and there are variable displacement turbochargers provided with a variable nozzle device. The exhaust gas passes through a scroll flow path formed in the turbine housing, then passes through a nozzle flow path defined by the variable nozzle device, and is supplied to the turbine rotor. A nozzle mounting portion and a nozzle plate of a variable nozzle device are supported by a nozzle support member in a state of being separated from each other, a nozzle flow path is formed between the nozzle mounting portion and the nozzle plate, and nozzle vanes are provided in the nozzle flow path.
Patent document 1 discloses the following technique: the nozzle plate is formed thicker than the nozzle mounting portion, so that the thermal deformation amount is reduced, the shearing force and the bending moment applied to the nozzle support member are reduced, and the damage of the nozzle plate and the nozzle support member is prevented. Patent document 1 discloses that the end of the nozzle support is fixed by caulking to a through hole formed in the nozzle plate or the nozzle mounting portion.
Documents of the prior art
Patent document
Patent document 1: international publication No. 2018/167931
Disclosure of Invention
Problems to be solved by the invention
When the nozzle support is caulked and fixed to the nozzle plate or the nozzle mounting portion, a portion of the nozzle support connected to the caulked portion deformed by the caulking process is deformed toward a surface side of a through hole formed in the nozzle plate or the nozzle mounting portion, and may be in a state of surface contact with the through hole. In this case, since the vibration load of the nozzle plate and the nozzle mounting portion is received by the contact portion, fretting fatigue may occur in the nozzle plate, and a crack may occur starting from an end portion of the contact portion. If fretting fatigue cracks occur, the fatigue limit of the nozzle support is greatly reduced.
The present disclosure is directed to suppressing fretting fatigue from occurring in a nozzle support member that is caulked and fixed to a nozzle plate or a nozzle mounting portion.
Means for solving the problems
(1) A nozzle device of an embodiment includes:
an annular nozzle plate;
an annular nozzle mounting portion that defines a nozzle flow path between the nozzle mounting portion and one surface of the nozzle plate;
at least one nozzle support member that joins the nozzle plate and the nozzle mounting portion and is riveted to at least the nozzle plate; and
at least one nozzle vane supported between the nozzle plate and the nozzle fitting,
the nozzle plate has a through-hole into which an end of the at least one nozzle support is inserted,
the through-hole includes:
a linear portion extending from the one surface of the nozzle plate toward the other surface;
an enlarged diameter portion formed on the other surface side of the nozzle plate and having a diameter larger than that of the linear portion; and
and a retreating processing portion formed in a part of the linear portion connected to the diameter-enlarged portion and having a diameter larger than that of the other part of the linear portion where the retreating processing portion is not formed.
In the structure of the above (1), the end portion of the nozzle support is inserted into the through hole of the nozzle plate, the end portion of the nozzle support is deformed by caulking and abuts on the surface on which the enlarged diameter portion is formed, and the nozzle plate is coupled to the nozzle support. According to the configuration of the above (1), since the through-hole has the relief portion formed in a part of the straight portion continuous with the enlarged diameter portion, even if a part of the nozzle support (hereinafter, also referred to as "non-caulked portion") continuous with the caulked portion in contact with the surface forming the enlarged diameter portion is deformed toward the surface forming the through-hole at the time of caulking, the non-caulked portion does not come into surface contact with the through-hole forming surface. Therefore, since there is no contact portion that serves as a starting point for the occurrence of fretting fatigue, the occurrence of fretting fatigue can be suppressed.
(2) In one embodiment, in the structure of the above (1),
the distance between the center of the through hole on the radially inner side of the nozzle plate and the surface on which the relief processing portion is formed is larger than the distance between the center of the through hole on the radially outer side of the nozzle plate and the surface on which the relief processing portion is formed.
According to the configuration of the above (2), since the distance between the center of the through hole on the inner side in the radial direction of the nozzle plate and the surface on which the relief processing portion is formed is larger than the distance between the center of the through hole on the outer side in the radial direction of the nozzle plate and the surface on which the relief processing portion is formed, even if the nozzle plate is thermally extended in a high-temperature environment to expand the diameter, the caulking portion does not come into contact with the surface on which the relief processing portion is formed. This can suppress the occurrence of fretting fatigue in the nozzle support.
(3) In one embodiment, in the structure of the above (2),
the center of the retreat processing portion is located at a position shifted inward in the radial direction of the nozzle plate with respect to the center of the through hole.
According to the configuration of the above (3), when the center of the relief processing portion is located at a position shifted to the inside in the radial direction of the nozzle plate, the relief processing portion can be formed so as to be easily cut by the cutting edge whose rotation center is shifted to the inside in the radial direction of the nozzle plate with respect to the center of the through hole.
(4) In one embodiment, in any of the structures (1) to (3) above,
at the outer diameter of the nozzle support part of A1The inner diameter of the retreating processing part is A2While the inner diameter A2Is 1.1 XA1Above and 1.5 XA1The following.
According to the structure of the above (4), by setting A2/A1The non-caulking portion can be prevented from contacting the surface on which the through hole is formed without excessively enlarging the formed relief processing portion, i.e., 1.1 to 1.5.
(5) A nozzle device of an embodiment includes:
an annular nozzle plate;
an annular nozzle mounting portion that defines a nozzle flow path between the nozzle mounting portion and one surface of the nozzle plate;
at least one nozzle support member that joins the nozzle plate and the nozzle mounting portion and is riveted to at least the nozzle plate; and
at least one nozzle vane supported between the nozzle plate and the nozzle fitting,
the nozzle plate has a through-hole into which an end of the at least one nozzle support is inserted,
the through-hole includes:
a linear portion extending from the one surface of the nozzle plate toward the other surface; and
an enlarged diameter portion formed on the other surface side of the nozzle plate and having a diameter larger than that of the linear portion,
the at least one nozzle support comprises:
a caulking portion that abuts against a surface on which the diameter-expanded portion is formed; and
and a non-caulking portion provided with a gap between a surface forming a part of the straight portion continuous to the diameter-enlarged portion and the non-caulking portion.
According to the structure of the above (5), since the non-caulking portion of the nozzle support has a gap with a surface forming a part of the straight portion continuous with the enlarged diameter portion of the through hole even after caulking, there is no contact portion which becomes a starting point of fretting fatigue. Therefore, the occurrence of fretting fatigue can be suppressed.
(6) In one embodiment, in any of the structures (1) to (5) above,
the surface forming the diameter-expanded portion is tapered.
According to the structure of the above (6), since the surface forming the enlarged diameter portion is tapered, the caulking portion can be enlarged in diameter along the tapered surface of the enlarged diameter portion at the time of caulking. This can reduce the load required to be applied to the end of the nozzle support member to form the caulked portion, and thus can suppress deformation of the non-caulked portion to the through-hole forming surface side.
(7) In one embodiment, in any of the structures (1) to (6) above,
the nozzle fitting part is fixed to the bearing housing,
the nozzle plate is supported by the nozzle mounting portion via the nozzle support.
According to the structure of the above (1), it is possible to suppress the occurrence of fretting fatigue in the nozzle support member caulked and fixed to the nozzle plate or the nozzle mounting portion due to the vibration load received from the nozzle plate or the nozzle mounting portion.
(8) In one embodiment, in any of the structures (1) to (7) above,
the nozzle plate has a coefficient of thermal expansion greater than that of the nozzle support.
According to the structure of the above (8), since the thermal expansion coefficient of the nozzle plate is larger than that of the nozzle support, when the nozzle plate and the nozzle support are heated in a high-temperature environment, the occurrence of backlash between the nozzle plate and the nozzle support can be suppressed.
(9) An exhaust turbocharger according to an embodiment includes a nozzle device having any one of the configurations (1) to (8) described above.
According to the configuration of the above item (9), fretting fatigue of the nozzle support provided in the nozzle device can be suppressed.
ADVANTAGEOUS EFFECTS OF INVENTION
According to some embodiments, the occurrence of fretting fatigue starting from a non-caulked portion connected to a caulked portion of a nozzle support provided in a nozzle device can be suppressed.
Drawings
Fig. 1 is a longitudinal sectional view of a variable displacement exhaust turbocharger according to an embodiment.
Fig. 2 is a view from direction a in fig. 1.
Fig. 3 is a partially enlarged longitudinal sectional view taken along line B-B in fig. 2.
FIG. 4 is a front view of a nozzle plate of an embodiment.
Fig. 5 is a cross-sectional view showing a caulking portion of a nozzle plate according to an embodiment.
Fig. 6 is a cross-sectional view showing a connection portion of the nozzle plate before caulking.
Fig. 7 is a cross-sectional view showing a caulking portion of a nozzle plate according to an embodiment.
Fig. 8 is a sectional view showing a caulking portion of a nozzle support in a conventional variable nozzle device.
Detailed Description
Hereinafter, several embodiments of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention, and are merely illustrative examples.
For example, expressions such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "central", "concentric", or "coaxial" indicate relative or absolute arrangements, and indicate not only arrangements as described above but also a state of relative displacement with a tolerance or an angle or a distance to such an extent that the same function can be obtained.
For example, the expression "square or cylindrical" indicates not only a shape such as a square or cylindrical shape in a strict geometrical sense but also a shape including a concave-convex portion, a chamfered portion, and the like within a range in which the same effect can be obtained.
On the other hand, the expression "provided with", "equipped with", "provided with", "including" or "having" one structural element is not an exclusive expression excluding the presence of other structural elements.
As shown in fig. 1 and 2, a variable displacement exhaust turbocharger 40 according to an embodiment includes: a turbine housing 44 that houses the turbine rotor 42 therein; a bearing housing 48 that houses therein a bearing 46 that rotatably supports the rotary shaft 42a of the turbine rotor 42; and a variable nozzle device 10 mounted inside an assembly formed by combining these housings. As the coupling member between the turbine housing 44 and the bearing housing 48, for example, in the example shown in fig. 1, the outer peripheral edge portion of the nozzle mounting portion 14, which will be described later, is clamped in the left-right direction in fig. 1 and fastened to each other by a fastening member such as a bolt. The nozzle fitting portion 14 and an annular groove portion formed in the bearing housing 48 form an internal space Si.
A compressor housing (not shown) is provided at a position opposite to the turbine housing 44 with the bearing housing 48 interposed therebetween. The compressor housing is coupled to the bearing housing 48, and a compressor rotor (not shown) is housed therein. The compressor rotor is coupled to the rotating shaft 42a of the turbine rotor 42, and rotates in conjunction with the rotation of the rotating shaft 42a to supercharge air supplied to the engine. An exhaust gas flow path F is formed inside the turbine housing 44, and a scroll flow path F (F) that communicates with an exhaust manifold (not shown) and through which exhaust gas discharged from the engine flows is formed on the outer peripheral side inside the turbine housing 441)。
The variable nozzle device 10 is disposed such that the axis 10a thereof is aligned with the axis of the turbine rotor 42, and is disposed outside the turbine rotor 42 in a direction (vertical direction in fig. 1) perpendicular to the axis of the turbine rotor 42 (a line aligned with the axis 10a in fig. 1). The variable nozzle device 10 is disposed in the scroll flow path F (F)1) And the turbine rotor 42, a nozzle flow path F (F) for flowing the exhaust gas is formed between them2). The arrow f in fig. 1 indicates the flow of the exhaust gas. Exhaust gas discharged from the engine passes through the swirl flow path F (F)1) Then passes through a nozzle flow path F (F) defined by the variable nozzle device 102) And then supplied to the turbine rotor 42. Thereafter, the exhaust gas is discharged from the exhaust outlet 50 to the outside of the turbine housing 44.
As shown in fig. 3, a variable nozzle device 10 according to one embodiment includes an annular nozzle plate 12 and a nozzle flow path F (F) defined between the nozzle plate 12 and one surface 12a thereof2) And an annular nozzle fitting portion 14. The nozzle plate 12 and the nozzle mounting portion 14 are joined by a nozzle support 16. The nozzle support 16 is riveted to at least the nozzle plate 12, and at least one nozzle vane 18 is disposed between the nozzle plate 12 and the nozzle mounting portion 14.
As shown in fig. 5, the nozzle plate 12 has a through-hole 13 into which an end portion (corresponding to the nozzle plate connecting portion 16a in fig. 5) of at least one nozzle support 16 is inserted, and the through-hole 13 has: a linear portion 13a extending from one surface 12a (the surface on the nozzle mounting portion 14 side) of the nozzle plate 12 toward the other surface 12 b; an enlarged diameter portion 13b formed on the other surface 12b side of the nozzle plate 12 and having a diameter larger than that of the linear portion 13 a; and a retreating portion 13c formed in a part of the linear portion 13a connected to the diameter-enlarged portion 13 b. The retreating processed portion 13c has a diameter larger than the other portion of the linear portion 13a where the retreating processed portion 13c is not formed. Therefore, nozzle plate 12 has linear portion forming surface 13as, enlarged diameter portion forming surface 13bs, and relief portion forming surface 13 cs. In fig. 5, 13cs' indicates a through-hole forming surface when the relief processing portion 13c is not formed.
The nozzle plate connecting portion 16a is inserted into the through hole 13, an end portion of the nozzle plate connecting portion 16a protrudes from an opening on the surface 12b side of the through hole 13, and the caulking process is performed by receiving the caulking load G at the protruding portion. By the caulking process, the end of the nozzle plate connecting portion 16a is deformed to be in contact with the enlarged diameter portion forming surface 13bs to form a caulked portion 16 f. Since the relief portion 13c is formed in a part of the straight portion 13a continuous with the enlarged diameter portion 13b of the through-hole 13, even if a part (non-caulked portion 16g) of the nozzle plate connecting portion 16a continuous with the caulked portion 16f is deformed toward the relief portion forming surface 13cs side of the through-hole 13 at the time of caulking, it does not contact the relief portion forming surface 13 cs. Therefore, since there is no contact portion that serves as a starting point for fretting fatigue, fretting fatigue can be suppressed from occurring in the nozzle support 16.
In the embodiment shown in fig. 5, a part of the caulking portion 16f has a shape protruding from the surface 12b of the nozzle plate 12. In another embodiment, the clinch portion 16f forms a smooth surface continuous with the surface 12 b.
Fig. 8 shows a state in which the nozzle support 100 is caulked and fixed to the nozzle plate 104 in the conventional variable nozzle device. The through hole 106 formed in the nozzle plate 104 includes a linear portion 106a and an enlarged diameter portion 106b formed in the opening. The nozzle plate 104 has a linear portion forming surface 106as and an enlarged diameter portion forming surface 106 bs. The nozzle plate connecting portion 102 is inserted into the through hole 106, and the caulking load G is received at the tip end portion of the nozzle plate connecting portion 102 to perform caulking. The caulking portion 102a is formed by caulking, and the caulking portion 102a is deformed (expanded) to be in contact with the expanded diameter portion 106 b. Since the relief portion 13c is not formed in the through hole 106as in the above-described embodiment, a part (non-caulked portion 102b) of the nozzle plate connecting portion 102 connected to the caulked portion 102a by the caulking process may be deformed to contact a part of the linear portion forming surface 106 as. When the non-caulking portion 102b comes into contact with a part of the straight portion forming surface 106as, the vibration load L is applied from the nozzle plate 104 to the non-caulking portion 102b, and the fretting fatigue crack c may occur starting from the end of the non-caulking portion 102 b. If fretting fatigue cracks c are generated, the fatigue limit is greatly reduced.
In one embodiment, as shown in fig. 3, the nozzle support 16 has a substantially cylindrical shape, and the nozzle plate coupling portion 16a and the nozzle fitting portion coupling portion 16b are formed with the smallest diameters. Facing the nozzle flow path F (F)2) The axial center portion 16c is formed to have a diameter larger than the nozzle plate connecting portion 16a and the nozzle mounting portion connecting portion 16 b. The nozzle plate 12 and the nozzle mounting portion 14 are locked to a step formed between the axial center portion 16c and the nozzle plate connecting portion 16a and the nozzle mounting portion connecting portion 16b, and the nozzle plate 12 and the ejection nozzle are fixed to each otherThe mouth fitting portion 14 is positioned.
In one embodiment, flanges 16d and 16e having a larger diameter than the central portion 16c are formed on both axial side portions of the central portion 16c, and the nozzle plate 12 and the nozzle mounting portion 14 are locked to the flanges 16d and 16e and positioned.
In the above embodiment, the nozzle support 16 is caulked to the nozzle plate 12, but as shown in fig. 3, the nozzle support 16 may be caulked to the nozzle mounting portion 14. In this case, the nozzle mounting portion coupling portion 16b is inserted into the through hole 14b formed in the nozzle mounting portion 14, and the tip end portion of the nozzle mounting portion coupling portion 16b is caulked to form the caulking portion 16 h. The caulking portion 16h is in surface contact with a diameter-enlarged portion formed at the exit opening of the through hole 14 b.
In one embodiment, as shown in fig. 3, nozzle plate 12 is formed in an annular shape and substantially plate-like shape. More specifically, the present invention comprises: an annular and plate-like body portion; and an extension portion 12c extending from the inner peripheral edge portion of the main body portion to the side (the right side in fig. 1) opposite to the nozzle fitting portion 14 so as to follow the outer peripheral shape of the turbine rotor 42. The extension 12c is integrally formed with the main body portion. In the main body portion, through holes 13 for locking the nozzle plate connecting portions 16a are formed in accordance with the number of the nozzle supports 16. In the embodiment shown in fig. 4, 4 through holes 13 are formed at 90 ° intervals in the circumferential direction of the nozzle plate 12.
In one embodiment, as shown in fig. 3, the nozzle fitting portion 14 is formed in an annular and substantially plate shape, supports the nozzle vanes 18 at an inner peripheral side portion, and is coupled to the nozzle support 16 at an outer peripheral side portion. That is, in the inner peripheral side portion, cylindrical through holes 14a for rotatably supporting the nozzle shafts 18a of the nozzle vanes 18 are formed in accordance with the number of the nozzle vanes 18, and in the outer peripheral side portion, through holes 14b for locking the nozzle mounting portion connecting portions 16b are formed in accordance with the number of the nozzle bearings 16. The through-hole 14b is arranged at a circumferential position corresponding to the through-hole 13 of the nozzle plate 12.
In one embodiment, as shown in fig. 3, the variable nozzle device 10 includes a nozzle vane variable portion 20. The nozzle blade variable portion 20 includes at least one lever plate 22 and a drive ring 24, and is disposed in the internal space Si. The rod plates 22 are provided in the same number as the nozzle vanes 18, and in the case of providing a plurality of them, they are circumferentially spaced apart from each other as shown in fig. 2. One end of the lever plate 22 is coupled to a protruding portion of the nozzle shaft 18a protruding into the internal space Si, and the other end is coupled to the drive ring 24. The drive ring 24 is formed in an annular and plate shape, and an inner peripheral surface thereof is disposed so as to face a stepped surface formed between an outer peripheral portion and an inner peripheral portion of the nozzle fitting portion 14. In addition, the drive ring 24 is provided to be rotatable with respect to the nozzle fitting portion 14.
Therefore, the nozzle vane variable portion 20 rotates the drive ring 24 by a predetermined angle, and the lever plate 22 operates in a linked manner, thereby changing the vane angle of the nozzle vanes 18. Further, the variable nozzle device 10 can increase and decrease the flow path area of the exhaust gas supplied to the turbine rotor 42 by changing the blade angle of the nozzle blade 18, and accordingly, can adjust the flow velocity of the exhaust gas supplied to the turbine rotor 42 and the supply amount to the turbine rotor 42, and thereby adjust the boost pressure of the air supplied to the engine.
In one embodiment, as shown in fig. 5, the enlarged diameter portion forming surface 13bs is a tapered surface inclined with respect to the axial direction of the nozzle plate connecting portion 16 a. In another embodiment, as shown in fig. 6, the enlarged diameter portion forming surface 13bs may be formed in a square cross section having a plane perpendicular and parallel to the axial direction of the nozzle plate connecting portion 16 a. Alternatively, the enlarged diameter portion forming surface 13bs may have another cross-sectional shape such as a circular shape or an elliptical shape.
In the embodiment shown in fig. 7, the contact area of the chamfered portion d (the contact portion between the caulking portion 16f and the enlarged diameter portion forming surface 13 bs) of the enlarged diameter portion forming surface 13bs having the tapered surface shown in fig. 5 is enlarged. This can increase the strength of the chamfered portion d against the vibration load L applied from the nozzle plate 12 to the nozzle plate connecting portion 16 a.
In one embodiment, as shown in fig. 4, the retreat working portion 13c is formed so as to be opposed to the center O of the through hole 131A distance L from the surface on which the retreating part 13c is formed1And L2In other words, the radially inner distance L2Is farther from the radially outer side of nozzle plate 12 by a distance L1Large (L)1<L2). According to this embodiment, even when the nozzle support 16 is thermally extended and the diameter is enlarged in a high-temperature environment, the caulking-free portion 16g does not contact the linear portion forming surface 13as of the through hole 13. Therefore, fretting fatigue can be suppressed from occurring in the nozzle support 16.
In one embodiment, as shown in fig. 4, the retreat working portion 13c is formed such that the center O of the retreat working portion 13c2Is located at the center O relative to the through hole 131A position shifted radially inward of nozzle plate 12. According to this embodiment, when the relief processing portion 13c is processed, the center axis of the cutting edge is positioned from the center O of the through hole 131Offset to the center O2The retreating processing portion 13c can be easily processed.
In one embodiment, as shown in fig. 5, the inner diameter a of the retreating processing portion 13c2Outer diameter A of the nozzle plate connecting portion 16a1Is A2＝1.1×A1～1.5×A1The relationship (2) of (c). According to this embodiment, by setting to A2/A1The non-caulking portion 16g can be prevented from contacting a part of the linear portion forming surface 13as without excessively enlarging the relief portion 13c to 1.1 to 1.5. This can suppress the occurrence of fretting fatigue in the nozzle support 16.
In one embodiment, the inner diameter A of the retreating section 13c is set to be larger than the inner diameter A of the inner wall2The retreat working portion 13c is formed to be smaller than the maximum diameter of the diameter-enlarged portion 13 b. Thus, when the retreating processing portion 13c is cut from the surface 12b side, the processing of the retreating processing portion 13c becomes easy.
In one embodiment, as shown in fig. 5 and 7, the nozzle plate connecting portion 16a of the nozzle support 16 includes: a caulking portion 16f abutting against the diameter expansion portion forming surface 13 bs; and a non-caulking portion 16g provided with a gap s between the straight portion forming surface 13as connected to the enlarged diameter portion forming surface 13 bs. According to this embodiment, since the gap s is present between the non-caulking portion 16g and a part of the linear portion forming surface 13as facing the non-caulking portion 16g, and there is no contact portion which becomes a starting point of occurrence of fretting fatigue, fretting fatigue occurring in the nozzle plate connecting portion 16a can be suppressed.
In one embodiment, as shown in fig. 5 and 7, the enlarged diameter portion forming surface 13bs is formed in a tapered shape. According to this embodiment, since the enlarged diameter portion forming surface 13bs is tapered, the caulking portion 16f formed in the nozzle plate connecting portion 16a at the caulking process can be enlarged in diameter along the tapered surface of the enlarged diameter portion forming surface 13 bs. This can reduce the load required for the caulking process to be applied to the nozzle support 16 during the caulking process, and thus can suppress the deformation of the non-caulked portion 16g toward the relief processed portion forming surface 13 cs.
In one embodiment, the material comprising nozzle plate 12 is selected to have a coefficient of thermal expansion greater than the coefficient of thermal expansion of the material comprising nozzle support 16. This can suppress the occurrence of backlash between nozzle plate 12 and nozzle support 16 when variable nozzle device 10 is heated in a high-temperature environment.
In one embodiment, when the nozzle mounting portion 14 and the nozzle support 16 are caulked and fixed, a material having a thermal expansion coefficient larger than that of a material constituting the nozzle support 16 is selected as a material constituting the nozzle mounting portion 14. This can suppress the occurrence of backlash between the nozzle mounting portion 14 and the nozzle support 16 when the temperature of the variable nozzle device 10 increases under a high-temperature environment.
Since the exhaust turbocharger 40 includes the variable nozzle device 10 according to the above-described embodiments, fretting fatigue occurring at the caulking portion where the nozzle plate connecting portion 16a or the nozzle mounting portion connecting portion 16b is caulked and fixed to the nozzle plate 12 or the nozzle mounting portion 14 can be suppressed. This can suppress fretting fatigue cracks in the nozzle support 16 and prevent fatigue failure.
The above embodiment is applied to the variable nozzle device 10 in which the blade angle of the nozzle vanes 18 can be changed, and the variable displacement exhaust turbocharger 40 including the variable nozzle device 10, but in other embodiments, it is applicable to a fixed nozzle device in which the blade angle of the nozzle vanes 18 is fixed, and a fixed displacement exhaust turbocharger including the fixed nozzle device.
Industrial applicability
According to some embodiments, in the nozzle device, the occurrence of fretting fatigue in the nozzle support member caulked and fixed to the nozzle plate or the nozzle mounting portion can be suppressed.
Description of the reference numerals
10 variable nozzle device
10a axis
12. 104 nozzle plate
12c extension
13. 106 through hole
13a, 106a straight line part
13b, 106b diameter-expanding part
13c retreat working part
13as, 106as straight line part forming surface
13bs, 106bs diameter-expanded part forming surface
13cs retreating work forming surface
14 nozzle assembly
14a, 14b through hole
16. 100 nozzle support
16a, 102 nozzle plate connecting part
16f, 16h, 102a riveting part
16b nozzle fitting part coupling part
16c axial central part
16d, 16e flange part
16g, 102b non-riveted part
18 nozzle blade
18a nozzle shaft
20 nozzle vane variable part
22 bar plate
24 drive ring
40 variable capacity type exhaust turbocharger
42 turbine rotor
42a rotating shaft
44 turbine housing
46 bearing
48 bearing shell
50 exhaust outlet
F waste gas flow path
F(F1) Vortex flow path
F(F2) Nozzle flow path
G riveting load
L vibration load
O1、O2Center of a ship
Si inner space
d chamfer part
f flow of exhaust gas
s gap.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：逆变器一体式气体供给装置