JP2018040317A - Supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a supercharger capable of suppressing the vibration of a heat insulation plate and reducing the wear thereof.SOLUTION: The supercharger includes a turbine housing 50, a bearing housing 10 assembled on the turbine housing 50, and a heat insulation plate 80 arranged between the turbine housing 50 and the bearing housing 10. An outer edge 81 of the heat insulation plate 80 having a cutout formed in the peripheral edge is held between the turbine housing 50 and the bearing housing 10 and supported in an elastically deformed state. In the state that the outer edge 81 of the heat insulation plate 80 is held and supported therebetween, an inner edge 84 of the heat insulation plate 80 is located between a turbine wheel 40 and the bearing housing 10 to abut on the bearing housing 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a supercharger.

  The supercharger described in Patent Literature 1 includes a turbine housing that houses a turbine wheel, and a bearing housing that is assembled to the turbine wheel. A bearing is accommodated in the bearing housing, and a rotating shaft having one end connected to the turbine wheel is supported by the bearing. The bearing housing and the turbine housing are in contact with each other at their peripheral portions.

  The turbocharger is also provided with a heat shield disposed between the turbine housing and the bearing housing. The outer edge portion of the heat shield plate is sandwiched between the turbine housing and the bearing housing and supported in an elastically deformed state. In a state where the outer edge portion of the heat shield plate is sandwiched and supported, the inner edge portion of the heat shield plate is located between the turbine wheel and the bearing housing, and covers the end surface of the bearing housing on the turbine housing side. Thereby, the heat input from the exhaust to the bearing housing is suppressed.

JP-A-7-189724

  In the supercharger described in Patent Document 1, the outer edge portion of the heat shield plate is sandwiched between the turbine housing and the bearing housing, but the inner edge portion of the heat shield plate is a free end spaced from the turbine housing and the bearing housing. ing. Therefore, the heat shield plate may vibrate depending on exhaust pulsation and the like, and the inner edge portion of the heat shield plate may be worn due to repeated contact with the bearing housing.

  A turbocharger for solving the above problems includes a turbine housing that houses a turbine wheel, and a bearing housing that supports a bearing that supports a rotating shaft having one end connected to the turbine wheel, and is assembled to the turbine housing. And a heat shield plate disposed between the turbine housing and the bearing housing, and an outer edge portion of the heat shield plate is formed with a notch at a peripheral edge thereof, and the turbine housing, the bearing housing, In the state where the outer edge portion of the heat shield plate is sandwiched and supported, the inner edge portion of the heat shield plate is interposed between the turbine wheel and the bearing housing. And is in contact with the bearing housing.

  In the above configuration, the outer edge portion of the heat shield plate is sandwiched between the turbine housing and the bearing housing and is supported in an elastically deformed state. In this state, the inner edge is in contact with the bearing housing. Therefore, vibration of the heat shield plate based on exhaust pulsation or the like generated when the inner edge portion of the heat shield plate is a free end is suppressed, and wear can be reduced.

Sectional drawing which expands and shows a part of structure of one Embodiment of a supercharger. The top view which shows the structure of a heat shield. It is sectional drawing of the supercharger which shows the attachment aspect of a heat shield, Comprising: The figure which shows the state of the heat shield before fastening a turbine housing and a bearing housing by V band. It is sectional drawing of the supercharger which shows the attachment aspect of a heat shield, Comprising: The figure which shows the state of the heat shield in the process of fastening a turbine housing and a bearing housing by V band. It is sectional drawing of the supercharger which shows the attachment aspect of a heat shield, Comprising: The figure which shows the state of a heat shield when a turbine housing and a bearing housing are assembled | attached by V band. The top view which shows the structure of the modification of a heat shield. Sectional drawing which expands and shows the structure of an outer edge part in the other modification of a heat shield.

One embodiment of a supercharger will be described with reference to FIGS.
As shown in FIG. 1, the turbocharger is provided with a bearing housing 10. The bearing housing 10 includes a main body portion 11 that houses the bearing 20 and a tapered portion 12 that is connected to one end of the main body portion 11 (left end in FIG. 1). A housing space 11A is formed inside the main body 11, and a bearing 20 is disposed in the housing space 11A. The tapered portion 12 is formed in a tapered shape having a reduced diameter as the distance from the main body portion 11 increases. The tapered portion 12 is formed with a through hole 12A that penetrates the tapered portion 12 and extends from the top surface 12B to the accommodating space 11A. The diameter of the through hole 12A is increased on the top surface 12B side. A rotary shaft 30 is inserted inside the bearing 20 of the through hole 12A and the accommodation space 11A. The rotating shaft 30 is rotatably supported by the bearing 20 accommodated in the accommodating space 11A with one end portion (left end portion in FIG. 1) protruding from the tapered portion 12. In the state where the rotating shaft 30 is inserted, the shape of the rotating shaft 30 and the shape of the through hole 12A are the same, and the rotating shaft 30 can slide in the circumferential direction with respect to the inner wall of the through hole 12A.

  In the main body 11, a flange 13 protruding in the radial direction perpendicular to the extending direction of the axis C of the rotating shaft 30 (hereinafter referred to as “axial direction”) is provided on the outer peripheral surface of the end portion on the tapered portion 12 side. Yes. The flange 13 is provided continuously over the entire circumference in the circumferential direction. At one end of the flange 13 on the tapered portion 12 side (left side in FIG. 1), a locking step 13A is recessed. As for the front-end | tip part of the flange 13, the end surface on the opposite side to the taper part 12 side inclines with respect to radial direction, and the thickness in an axial direction is short toward the front-end | tip side.

  A turbine wheel 40 is connected to the one end of the rotating shaft 30. The turbine wheel 40 can rotate integrally with the rotary shaft 30 about the axis C of the rotary shaft 30. The turbine wheel 40 is accommodated in the turbine housing 50. The turbine housing 50 constitutes an exhaust passage, and the turbine wheel 40 is rotated by the exhaust gas flowing through the exhaust passage. The turbine housing 50 includes a scroll portion 51 that guides exhaust gas swirled in the circumferential direction to the turbine wheel 40, and a cylindrical portion 52 that is connected to the scroll portion 51 and extends in the axial direction. As indicated by a two-dot chain line arrow in FIG. 1, the flow of the exhaust led out from the scroll portion 51 toward the turbine wheel 40 is directed toward the axial direction when passing through the turbine wheel 40, and the cylindrical portion 52 is discharged.

  The turbine housing 50 is also provided with a locking portion 53 connected to the end surface of the scroll portion 51 on the bearing housing 10 side. The locking portion 53 protrudes from the peripheral edge portion of the end surface toward the bearing housing 10 side. The locking portion 53 has a shape that gradually increases in diameter toward the flange 13 side (right side in FIG. 1) in the axial direction, and engages with the locking step 13A. Then, with the locking portion 53 engaged with the locking step 13A, the outer peripheral edge of the locking portion 53 and the flange 13 are fastened by the V-band 60, whereby the turbine housing 50 and the bearing housing 10 are assembled. It has been. Note that the V band 60 is provided continuously over the entire circumferential direction of the locking portion 53 and the flange 13.

  The length L1 in the axial direction of the locking portion 53 is longer than the length L2 in the axial direction of the locking level difference 13A (L1> L2). Therefore, a gap 70 is formed between the scroll portion 51 and the flange 13 in a state where the locking portion 53 is engaged with the locking level difference 13A. An outer edge portion 81 of the heat shield plate 80 is inserted into the gap 70.

  As shown in FIGS. 1 and 2, the heat shield plate 80 is made of metal, and has an outer edge portion 81 and a shoulder extending from the outer edge portion 81 along the circumferential surface of the tapered portion 12 of the bearing housing 10. A bottom portion 83 extending radially inward from the shoulder portion 82, and an inner edge portion 84 connected to the inner peripheral edge of the bottom portion 83. The shoulder portion 82 and the bottom portion 83 are separated from the bearing housing 10. The bottom 83 and the inner edge 84 are located between the turbine wheel 40 and the bearing housing 10. That is, the inner edge portion 84 is located between the end surface of the turbine wheel 40 on the bearing housing 10 side and the top surface 12B of the bearing housing 10 facing the end surface. The inner edge portion 84 is bent and extended from the bottom portion 83 toward the bearing housing 10, and an inner peripheral portion thereof is in contact with the top surface 12 </ b> B of the tapered portion 12. Thus, the heat shield plate 80 is disposed so as to cover the end surface of the bearing housing 10 on the turbine housing 50 side. Since the outer edge portion 81 and the inner edge portion 84 of the heat shield plate 80 are in contact with the bearing housing 10, the heat shield plate 80 and the bearing housing 10 constitute a heat insulating space 90 that is isolated from the internal space of the turbine housing 50. Has been. Thereby, the heat input from the exhaust to the bearing housing 10 is suppressed. An insertion hole 84A is formed in the inner edge portion 84, and the rotary shaft 30 is connected to the turbine wheel 40 through the insertion hole 84A. The inner edge portion 84 and the rotary shaft 30 are separated from each other.

  As shown in FIGS. 1 and 2, the outer edge portion 81 extends radially outward from the shoulder portion 82, and comes into contact with the contact portion 81 </ b> A in contact with the bearing housing 10, and radially from the periphery of the contact portion 81 </ b> A It has a section 81B that extends outward and bends and extends toward the turbine housing 50. Therefore, as shown in FIG. 1, the outer edge part 81 is formed in the shape bent in the cross section. As shown in FIG. 2, the outer edge portion 81 has a plurality of cutouts 81C at the periphery. The notches 81C are provided at equal intervals in the circumferential direction. By the notches 81C, a plurality of pieces 81B are formed in the outer edge 81 in the circumferential direction.

A method for attaching the heat shield plate 80 will be described.
As shown in FIG. 3, when the bearing housing 10 and the turbine housing 50 are assembled, first, the outer edge portion 81 of the heat shield plate 80 is brought into contact with the end surface of the scroll portion 51 of the turbine housing 50, so The inner edge 84 of 80 is brought into contact with the top surface 12B of the bearing housing 10. As a result, the heat shield plate 80 is disposed between the turbine housing 50 and the bearing housing 10. And the latching | locking part 53 of the turbine housing 50 and the latching level | step difference 13A of the bearing housing 10 are engaged. At this time, a gap is generated between the locking portion 53 and the flange 13. In this state, the outer edge portion 81 is not in contact with the bearing housing 10. Thereafter, the locking portion 53 and the peripheral edge portion of the flange 13 are fastened by the V band 60.

  In this fastening process, the outer edge portion 81 of the heat shield plate 80 is pressed toward the bearing housing 10 by the turbine housing 50, and the inner edge portion 84 of the heat shield plate 80 is pressed toward the turbine housing 50 side by the bearing housing 10. . Therefore, as shown in FIG. 4, in the process of fastening the locking portion 53 and the peripheral portion of the flange 13, the bottom portion 83 and the shoulder portion 82 of the heat shield plate 80 are elastically deformed, and the inner edge portion 84 is connected to the turbine wheel 40. It will be in the state pressed against the bearing housing 10 in the position between the bearing housing 10. Further, in such a process, the gap 70 through which the outer edge portion 81 is inserted gradually decreases, so that the contact portion 81A of the outer edge portion 81 and the bearing housing 10 come into contact with each other.

  As shown in FIG. 5, when the peripheral portion of the locking portion 53 and the flange 13 is further fastened by the V-band 60 from that state, the section 81B is moved to the bearing housing by the turbine housing 50 at the outer edge portion 81 of the heat shield plate 80. The contact portion 81 </ b> A is pressed toward the turbine housing 50 by the bearing housing 10. Therefore, the outer edge portion 81 is deformed so that the section portion 81B extends radially outward as indicated by an arrow in FIG. When the engaging portion 53 and the flange 13 come into contact with each other and the bearing housing 10 and the turbine housing 50 are assembled to each other, the outer edge portion 81 of the heat shield plate 80 is sandwiched between the turbine housing 50 and the bearing housing 10 and elastically deformed. It is supported in the state. In this state, the inner edge portion 84 is located between the turbine wheel 40 and the bearing housing 10 and is in contact with the bearing housing 10.

Next, the effect of this embodiment is demonstrated.
(1) In the present embodiment, the outer edge portion 81 of the heat shield plate 80 is sandwiched between the turbine housing 50 and the bearing housing 10 and supported in an elastically deformed state. In this state, the inner edge portion 84 is pressed against and in contact with the bearing housing 10. That is, the outer edge portion 81 of the heat shield plate 80 is supported by the bearing housing 10 and the turbine housing 50, and the inner edge portion 84 of the heat shield plate 80 is supported by the bearing housing 10. Therefore, the heat shield plate 80 is suppressed from vibration based on exhaust pulsation or the like generated when the inner edge portion 84 is a free end, and can reduce its wear.

  (2) In the heat shield plate 80, the exhaust gas hardly flows to the outer edge portion 81 far from the turbine wheel 40 as compared with the inner edge portion 84 close to the turbine wheel 40. For this reason, the amount of heat input from the exhaust to the outer edge portion 81 is smaller than the amount of heat input from the exhaust to the inner edge portion 84. In the present embodiment, since the outer edge portion 81 is sandwiched and supported by the bearing housing 10 and the turbine housing 50, it is possible to suppress a decrease in the support function of the heat shield plate 80 due to the influence of heat.

  (3) The heat shield plate 80 has an inner edge portion 84 and an outer edge portion 81 in contact with the bearing housing 10, and constitutes a heat insulating space 90 that is isolated from the inner space of the turbine housing 50. Therefore, it becomes difficult for exhaust to flow between the heat shield plate 80 and the bearing housing 10, and heat input to the bearing housing 10 can be suitably suppressed.

  (4) In the present embodiment, a notch 81C is formed in the outer edge portion 81, and a portion sandwiched between the bearing housing 10 and the turbine housing 50 is defined as a section portion 81B. Therefore, even when the distance between the contact with the bearing housing 10 and the contact with the turbine housing 50 at the outer edge 81 is short, the outer edge 81 can be easily deformed and its spring constant can be lowered. Therefore, compared with the structure which enlarges the outer edge part 81 to radial direction and reduces a spring constant, it can contribute to size reduction of the heat shield 80.

  (5) In this embodiment, the spring constant of the outer edge part 81 is set low. Therefore, for example, it is possible to employ a fastening structure using a V band 60 having a weak fastening force as compared with a fastening structure such as bolt fastening. Accordingly, the degree of freedom in selecting the fastening material can be improved.

  (6) In this embodiment, since the notch 81C is formed in the outer edge portion 81, the outer edge portion 81 is likely to be deformed in the circumferential direction when thermally expanding. For this reason, it is possible to suppress the thermal stress generated in the outer edge portion 81 from becoming excessive. As a result, the durability of the heat shield plate 80 can be improved.

The above embodiment can be implemented with the following modifications.
In the outer edge portion 81 of the heat shield plate 80, the notches 81C may be provided at different intervals in the circumferential direction. Further, the number of the notches 81C can be changed as appropriate. It is possible to change the spring constant of the intercept portion 81B by appropriately setting the number of notches 81C and the arrangement position. That is, the number and arrangement position of the notches 81C may be set so that the spring constant of the intercept portion 81B is within a desired range.

  -The shape of the notch 81C of the heat shield plate 80 can be changed. For example, as shown in FIG. 6, you may employ | adopt the structure which changed the depth of a notch. In addition, about the structure similar to the said embodiment, a common code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

  As shown in FIG. 6, a notch 100 is provided in the outer edge portion 81 of the heat shield plate 80. The notch 100 is configured to be notched from the peripheral edge of the outer edge portion 81 until reaching the shoulder portion 82. When the heat shield plate 80 is attached to the turbocharger, the heat insulating space 90 and the internal space of the turbine housing 50 communicate with each other.

  In the above configuration, the heat insulating space 90 and the internal space of the turbine housing 50 communicate with each other, and the exhaust can flow into the heat insulating space 90. Therefore, even if exhaust pulsation occurs, the pressure difference between the heat insulation space 90 and the internal space of the turbine housing 50 is suppressed, and generation of force acting on the inner edge portion 84 in the direction away from the bearing housing 10 can be suppressed. it can. Therefore, even if the force that presses the inner edge portion 84 against the bearing housing 10 is weakened due to plastic deformation of the shoulder portion 82 and the bottom portion 83 under the influence of heat, and the spring effect due to the elastic deformation is weakened, the heat shield plate 80 It is possible to ensure the effect of reducing the wear of the steel.

  Further, the shape of the notches 81C and 100 may be such that the circumferential length of the outer edge 81 is longer, and the circumferential length of the outer edge 81 is shorter. May be.

-The structure of the outer edge part 81 of the heat shield 80 is not restricted to what was mentioned above. For example, the configuration shown in FIG. 7 can be adopted.
As shown in FIG. 7, the outer edge portion 81 has a connecting portion 110 that is connected to the shoulder portion 82 and extends in the radial direction. The connecting portion 110 is not in contact with the bearing housing 10 and the turbine housing 50. The connecting portion 110 is connected to an extending portion 111 that extends radially outward and bends and extends toward the turbine housing 50. The extension part 111 is in contact with the turbine housing 50. The extending portion 111 is connected to a peripheral edge portion 112 that extends radially outward and bends and extends toward the bearing housing 10. The distal end of the peripheral edge 112 abuts on the bearing housing 10. The outer edge portion 81 has a cutout at the periphery. In the outer edge portion 81, the extending portion 111 is pressed toward the bearing housing 10 by the turbine housing 50, and the peripheral edge portion 112 is pressed toward the turbine housing 50 side by the bearing housing 10. Thereby, it is elastically deformed. Even with such a configuration, the outer edge 81 can be elastically deformed in a state where the outer edge 81 of the heat shield plate 80 is sandwiched and supported by the bearing housing 10 and the turbine housing 50.

  A locking step may be formed at the end of the locking portion 53 on the flange 13 side, and a locking portion protruding toward the locking portion 53 may be formed on the flange 13. In this case, the bearing housing 10 and the turbine housing 50 are assembled by engaging the engaging portion of the flange 13 with the engaging step of the engaging portion 53 and fastening the outer peripheral edge portions thereof with the V band 60. Can be attached. In this case, the gap 70 is formed by making the length of the locking portion in the flange 13 in the axial direction longer than the length of the locking step in the locking portion 53 in the axial direction.

  -The fastening structure at the time of assembling the bearing housing 10 and the turbine housing 50 is not restricted to the thing by V band. For example, the bearing housing 10 and the turbine housing 50 may be fastened and assembled with bolts.

  In the state where the outer edge portion 81 is sandwiched and supported by the bearing housing 10 and the turbine housing 50, the shoulder portion 82 and the bottom portion 83 may be in contact with the bearing housing 10.

  DESCRIPTION OF SYMBOLS 10 ... Bearing housing, 11 ... Main-body part, 11A ... Accommodating space, 12 ... Tapered part, 12A ... Through-hole, 12B ... Top surface, 13 ... Flange, 13A ... Locking step, 20 ... Bearing, 30 ... Rotating shaft, 40 ... Turbine wheel, 50 ... Turbine housing, 51 ... Scroll part, 52 ... Cylindrical part, 53 ... Locking part, 60 ... V band, 70 ... Gap, 80 ... Heat shield plate, 81 ... Outer edge part, 81A ... Contact Part, 81B ... section part, 81C ... notch, 82 ... shoulder part, 83 ... bottom part, 84 ... inner edge part, 84A ... insertion hole, 90 ... insulation space, 100 ... notch, 110 ... connecting part, 111 ... extension Part, 112 ... peripheral part.

Claims (1)

A turbine housing that houses a turbine wheel;
A bearing housing that houses a bearing that supports a rotating shaft having one end connected to the turbine wheel, and is assembled to the turbine housing;
A heat shield disposed between the turbine housing and the bearing housing;
The outer edge portion of the heat shield plate has a notch formed in the periphery thereof, and is supported by being elastically deformed by being sandwiched between the turbine housing and the bearing housing,
In a state where the outer edge portion of the heat shield plate is sandwiched and supported, the inner edge portion of the heat shield plate is located between the turbine wheel and the bearing housing and is in contact with the bearing housing. Machine.

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