JP2014129735A - Heat shielding plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat shielding plate capable of inhibiting the occurrence of vibrations when being thermally deformed.SOLUTION: A heat shielding plate 1 includes: a bottom part 2 provided between a bearing housing 102 and a turbine housing 101 of a super charger, the bottom part 2 in which a hole 5 is formed at a center part; a shoulder part 3 which extends from the bottom part 2 and curves so as to cover the bearing housing 102; and a flange part 4 extending outward from an end part of the shoulder part 3. The bottom part 2 is supported by the turbine housing 101 and the flange part 4 is supported by the bearing housing 102. In the heat shielding plate 1, a protruding part 6 which has a lower surface 7 having an arc shaped cross section and protrudes in a direction that moves away from the bearing housing 102 is formed at an inner peripheral edge 5a of the bottom part 2.

Description

  The present invention relates to a heat shield plate provided between a bearing housing and a turbine housing in a supercharger.

Conventionally, the thing of patent document 1 is known as such a heat shield. FIG. 3 is a cross-sectional view of a supercharger including such a heat shield.
As shown in FIG. 3, the supercharger 100 includes a turbine housing 101 into which exhaust flows and a bearing housing 102 assembled to the turbine housing 101. A turbine wheel 103 is provided in the turbine housing 101. A rotating shaft 104 is connected to the turbine wheel 103, and the rotating shaft 104 is rotatably supported by the bearing housing 102. Between the housings 101 and 102, a bottomed cylindrical heat shield plate 105 that covers an end of the bearing housing 102 is provided.

FIG. 4 is an enlarged cross-sectional view of the heat shield plate 105 of FIG.
As shown in FIG. 4, the heat shield plate 105 is disposed on the turbine wheel 103 side and extends in a direction perpendicular to the rotation shaft 104 (left and right direction in the figure) and has a bottom portion 106 provided with a hole in the center thereof. The shoulder portion 107 extends from the outer periphery of the bottom portion 106 and curves to cover the bearing housing 102, and the flange portion 108 extends outward from the end portion of the shoulder portion 107.

  Such a heat shield plate 105 is assembled to the supercharger 100 as follows. That is, in a state where the heat shield plate 105 is provided between the housings 101 and 102, the flange portion 108 is pressed downward in FIG. 4 by the turbine housing 101. On the other hand, the bottom portion 106 is pressed upward in FIG. 4 by a support portion 109 provided on the bearing housing 102. Therefore, the heat shield plate 105 is elastically deformed in the axial direction of the rotating shaft 104 (up and down direction in FIG. 4), and the flange 108 is supported by the turbine housing 101 and the bottom 106 is supported by the bearing housing 102 by the reaction force.

  When the heat shield plate 105 is assembled in this way, the exhaust gas flowing into the turbine housing 101 is suppressed from coming into contact with the bearing housing 102. Therefore, the temperature rise of the bearing housing 102 can be suppressed, and the thermal deterioration of the oil in the bearing housing 102 can be suppressed.

JP 58-5429 A

  As shown in FIG. 5, when such a heat shield plate 105 is heated by exhaust, the shoulder 107 is thermally deformed so as to protrude toward the turbine wheel 103 with the corner of the inner peripheral edge 110 of the bottom portion 106 as a fulcrum. As a result, the bottom 106 and the bearing housing 102 come into contact with the corners of the bottom, that is, linearly, and the contact area between the bottom 106 and the bearing housing 102 decreases. Therefore, the heat shield plate 105 is likely to be separated from the support portion 109, and the heat shield plate 105 may vibrate and cause noise and wear.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a heat shield plate capable of suppressing generation of vibration even when it is thermally deformed.

  A heat shield for solving the above problems is provided between the bearing housing of the turbocharger and the turbine housing, and is curved so as to cover the bearing housing by extending from the bottom with a hole provided in the center. And a collar portion extending outward from an end portion of the shoulder portion. The bottom portion is supported by the turbine housing and the flange portion is supported by the bearing housing. In such a heat shield plate, a projecting portion is formed on the inner peripheral edge of the bottom portion so that its lower surface has an arcuate cross section and projects away from the bearing housing.

  In the above configuration, the bottom surface of the heat shield plate is formed in an arc shape in cross section, and the heat shield plate and the bearing housing are in contact with each other at the surface. The contact area between the bearing housing and the bearing housing can be increased. Therefore, the heat shield plate can be prevented from being separated from the bearing housing, and the state where the heat shield plate is supported by each housing can be maintained. Therefore, even when the heat shield plate is thermally deformed, generation of vibration can be suppressed.

The expanded sectional view which shows one Embodiment of a heat shield. Sectional drawing which shows the shape after a thermal deformation in the heat shield of the embodiment. Sectional drawing which shows the structure of a supercharger provided with the conventional heat shield. Sectional drawing which expands and shows the structure of the conventional heat shield. Sectional drawing which shows the shape after thermal deformation in the conventional heat shield.

Hereinafter, an embodiment of a heat shield plate will be described with reference to FIGS. 1 and 2. In addition, about the structure similar to the supercharger shown in FIG. 3, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.
As shown in FIG. 1, the heat shield plate 1 includes a bottom portion 2 disposed on the turbine wheel 103 side, a shoulder portion 3 extending from the bottom portion 2 and curved so as to cover the bearing housing 102, and the shoulder portion 3. And an eaves portion 4 extending outward from the end portion. The bottom portion 2 extends in a direction orthogonal to the rotation shaft 104 (the left-right direction in FIG. 1), and a hole 5 through which the rotation shaft 104 and the turbine wheel 103 are passed is provided at the center. On the inner peripheral edge 5 a of the bottom 2 forming such a hole 5, a protruding portion 6 is provided over the entire periphery thereof so as to stand away from the bearing housing 102. The protrusion 6 has a surface facing the bearing housing 102, that is, a lower surface 7 of which has an arcuate cross section. The lower surface 7 is in contact with the support portion 109 of the bearing housing 102.

  Further, the shoulder portion 3 of the heat shield plate 1 does not protrude toward the turbine wheel 103 (upper side in the drawing) from the bottom portion 2 in the axial direction (vertical direction in the drawing) of the rotating shaft 104, and from the bottom portion 2. Is also located on the bearing housing 102 side (lower side in the figure).

  When the heat shield plate 1 is provided between the turbine housing 101 and the bearing housing 102, the flange 4 is pressed downward by the turbine housing 101, while the lower surface 7 of the protrusion 6 supports the bearing housing 102. The portion 109 is pressed upward. Therefore, the heat shield plate 1 is elastically deformed, and the flange 4 is supported by the turbine housing 101 and the bottom 2 is supported by the bearing housing 102 by the reaction force.

Next, the operation of the heat shield plate 1 having such a configuration will be described.
The heat shield plate 1 is provided with a protrusion 6 having a lower surface 7 having an arcuate cross section on the entire circumference of the inner peripheral edge 5 a of the bottom 2. Therefore, as shown in FIG. 2, even if the heat shield plate 1 is thermally deformed and the shoulder 3 protrudes toward the turbine wheel 103 with the lower surface 7 as a fulcrum, the bottom 2 and the bearing housing 102 are in contact with each other on the surface. Thus, the contact area can be increased. Therefore, it is possible to suppress the heat shield plate 1 from being separated from the bearing housing 102 and maintain the state in which the heat shield plate 1 is supported by the housings 101 and 102. The

  The shoulder portion 3 is more likely to come into contact with the exhaust than the bottom portion 2 and the flange portion 4 and has a large amount of thermal deformation. And before thermal deformation, it is located closer to the bearing housing 102 than the bottom 2. Therefore, when such a shoulder portion 3 is thermally deformed, the shoulder portion 3 protrudes largely toward the turbine wheel 103 with the lower surface 7 as a fulcrum. When the shoulder 3 is deformed in this way, the gap between the heat shield plate 1 and the turbine wheel 103 is reduced, so that the amount of exhaust gas flowing into the gap is reduced. As a result, most of the exhaust gas flowing into the turbine housing 101 can be introduced into the turbine wheel 103, and the supercharging efficiency of the supercharger 100 can be improved.

According to the first embodiment described above, the following effects can be obtained.
(1) On the inner peripheral edge 5 a of the bottom portion 2 of the heat shield plate 1, a protruding portion 6 whose bottom surface 7 has a circular arc shape and protrudes away from the bearing housing 102 is formed. Therefore, even when the heat shield plate 1 is thermally deformed, the vibration can be suppressed.

In addition, the said one Embodiment can also be implemented with the following forms which changed this suitably.
In the above-described embodiment, the shoulder 3 has a shape that does not protrude from the bottom 2 toward the turbine wheel 103 in the axial direction of the rotary shaft 104, but the shoulder 3 protrudes from the bottom 2 toward the turbine wheel 103. It is good also as a shape. Even in such a case, the same effect as the above (1) can be obtained.

  In each of the above embodiments, the protruding portion 6 is formed by bending the inner peripheral edge 5a of the bottom portion 2, but the inner peripheral edge 5a can be increased by making the inner peripheral edge 5a of the bottom portion 2 thicker than other portions. May be protruded in a direction away from the bearing housing 102. Even in such a configuration, the same effect as the above (1) can be obtained if the lower surface 7 facing the bearing housing 102 is formed in a circular arc shape in the protruding portion.

  In each of the above embodiments, the protruding portion 6 is formed on the entire circumference of the inner peripheral edge 5a. However, if the contact area between the bottom portion 2 and the bearing housing can be sufficiently secured when thermally deformed, You may make it provide the protrusion part 6 in a part of periphery 5a.

DESCRIPTION OF SYMBOLS 1 ... Heat shield board, 2 ... Bottom part, 3 ... Shoulder part, 4 ... Gutter part, 5 ... Hole, 5a ... Inner peripheral edge, 6 ... Projection part, 7 ... Lower surface, 100 ... Supercharger, 101 ... Turbine housing, 102 DESCRIPTION OF SYMBOLS ... Bearing housing, 103 ... Turbine wheel, 104 ... Rotating shaft, 105 ... Heat shield, 106 ... Bottom part, 107 ... Shoulder part, 108 ... Gutter part, 109 ... Support part, 110 ... Inner peripheral edge.

Claims (1)

A bottom portion provided between the bearing housing and the turbine housing of the turbocharger, having a hole in the center, a shoulder portion extending from the bottom portion and curved so as to cover the bearing housing, and an end portion of the shoulder portion; A heat shield plate having a flange extending outward from the bottom, the bottom portion being supported by the turbine housing and the flange being supported by the bearing housing,
A heat shield plate, wherein an inner peripheral edge of the bottom portion is formed with a protruding portion that protrudes in a direction away from the bearing housing with a lower surface having an arcuate cross section.