JPS6027814B2 - supercharger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a weekly payer for a gasoline engine that discharges high-temperature exhaust gas.

In order to connect the turbine case and center housing of a conventional supercharger, a flange portion of the center housing is iron-fitted to a stepped portion of the turbine case and bolted.

However, with this structure, heat from the turbine case is easily transmitted to the center housing, causing a problem in that the bearing portion in the center housing becomes hot and seizes when the engine is stopped. In order to improve this, the peripheral part of the dish-shaped heat shield plate is sandwiched between the joining surfaces of the turbine case and the center housing, and the central part is connected to the blade end surface of the turbine impeller, the inner surface of the turbine case, and the end surface of the center housing. It was intended to be interposed in the annular space formed by.

That is, this heat shield plate surrounds the end face of the center/using to prevent it from coming into direct contact with high temperature exhaust gas. As a result, the temperature rise in the center housing was considerably suppressed and good results were obtained, but the heat conduction from the sandwiched part of the heat shield became significant, and the temperature of the bearing part was still reduced to a sufficiently safe point. It cannot be lowered. Especially when the engine is stopped after high-speed driving, the maximum
The heat of the turbine case, which has been heated to about 750°C by the exhaust gas heated to 90,000°C, is transmitted to the center housing via the retaining part of the shielding plate, etc., and rises to 300-350qo.

If this happens, the lubricating oil in the bearing may compete with each other, and the piston ring attached to the rotating shaft that contacts the end hole of the center housing may become deformed, causing failures such as making the weekly pay machine operate unsmoothly. was occurring. An object of the present invention is to provide a supercharger that can suppress the temperature rise of the centanousing with a relatively simple structure and operate smoothly. In the weekly payer, the center housing includes a center housing that supports the rotating shaft of the car with a bearing part, and a blocking plate installed between the turbine case and the center housing, and the center housing has a tip hole in which the center housing receives the rotation through a piston ring. The heat shield plate is airtightly iron-fitted to the shaft, and the flange part engages with the step part of the turbine case via the peripheral part of the heat shield plate, and the heat shield plate is made of a dish-shaped body having a center hole; The center hole is held freely relative to the rotating shaft within an annular space formed by the blade end surface of the turbine impeller, the inner surface of the turbine case, and the end of the center housing, and a peripheral portion thereof is connected to the turbine case. Of the first heat shield plate held between the engaging portions of the center housing and the second heat shield plate whose peripheral portions are only held by the engaging portions, at least the second heat shield plate is It is characterized by being made of a board.

FIG. 1 is a sectional view of a supercharger according to an embodiment of the present invention.

This figure shows the state in which a turbine case 1 having a spiral passage 2 for introducing high-temperature exhaust gas is connected to a center housing 5 that supports a rotating shaft 6 with a turbine impeller 3 fixed to its end in a bearing 7. The flange portion 12 of the housing 5 is engaged with the stepped portion 13 at the right end of the turbine case, and the bolts 15 are used to connect the housing 5 with the seat plate 14 interposed therebetween. Note that an enlarged view of this portion is shown in FIG.
Exhaust gas enters the spiral passage 2 from below, swirls, rotates the turbine impeller 3, and then is discharged from the gas outlet 4.

The rotating shaft to which the turbine impeller 3 is fixed is supported by a bearing part 7, and a piston ring 9 is attached to the rotating shaft 6 between the part that is iron-coupled to the bearing part 7 and the part to which the turbine impeller 3 is fixed. It is mounted and engaged with a hole at the left end of the center housing 5 to prevent exhaust gas from entering the center housing 5. Further, a large amount of lubricating oil flows through an oil passage 8 formed in the center housing 5, overflows the bearing portion 7, flows out from the oil outlet 16, and circulates.

That is, the bearing portion 7 and the center housing 5 are also cooled with a large amount of lubricating oil. Step part 1 of the evening bin case
3 and the flange portion 12 of the center housing 5, an open square portion of a dish-shaped heat shield plate 10 made of fusen steel plate is sandwiched, and the rear side of the turbine impeller 3 and the left end surface of the center housing 5 are connected. The space between them is divided into air chambers 11a and 11b.

FIG. 2 is a plan view of the heat shield plate shown in FIG. 1, in which the annular portion 18 and the projection 19 shown with diagonal lines indicate the end face of the opening.

For example, it is a shallow dish-shaped piece made by punching and molding a fusen steel plate with a press, and a hole is provided in the center of the plate into which the root of the turbine impeller 3 is inserted. Further, three protrusions 19 are provided around the closing part, and the space between the protrusions 19 is a cutout part 17. That is, three protrusions 19 per heat shield plate are sandwiched between the turbine case 1 and the center housing 5, and the annular portion 18 only partitions the air chambers la and 11b. FIG. 3 is an enlarged view of the connection portion between the turbine case and the center housing in FIG. 1.

The periphery of the entrance part of the heat shield plate 10 and the flange part 12 of the center housing 5 are inserted into the stepped part 13 of the turbine case 1 and are held down by the seat plate 14. However, the heat shield plate 1 is only held down by three protrusions 19 formed at the mouth of the river, and the annular portion 18 serves to prevent exhaust gas from entering the air chamber 11b. Therefore, the contact surface 22 from the turbine case 1 to the heat shield plate 10 and the flange portion 12
The amount of heat transmitted through the turbine case decreases, and the heat transmitted to the center housing 5 through the drum drum surface 21 of the turbine case becomes dominant, and the amount of heat transmitted to the center housing 5 is halved. The weekly pay machine configured in this way has 850
When ~900 oo of exhaust gas is introduced, the temperature of the left side of the heat shield plate 10 that grows on it becomes about 750 degrees Celsius, but the temperature of the back side thereof is about 50 degrees Celsius, and the fin radiation heat from this surface and the contact surface 22
Even if there is heat transfer through the drum face 21, the center/
・The temperature of the housing 5 drops to about 300oC. In addition, since the bearing part 7 is cooled with a large amount of lubricating oil,
It is as follows. However, when the engine stops, the flow of lubricating oil also stops, so the heat from the turbine case is transferred to the center housing 5 and rises to about 40 mm.

When the conventional heat shield plate 10 without the cutout part 17 was used, the temperature increased to 450oo, so the heat shield plate 10 in FIG.
By using this, a temperature drop of about 500C was caused. In addition, the temperature of the bearing part 7 conventionally rose to about 200qC, but in this embodiment it rose to about 15000qC, which also caused a temperature drop of about 5000qC. There is no carbon bridge caused by oil competition, and it operates smoothly for a long time. In the heat shield structure of this embodiment, the sandwiching portion of the heat shield plate, which is interposed between the turbine case and the center housing to prevent exhaust gas from directly contacting the center housing, is limited to only the protruding portion thereof. By doing so, it is possible to significantly reduce heat conduction in this part, suppress the temperature rise of the bearing part when the engine is stopped, prevent the formation of carbon bridges, and enable smooth operation for a long period of time.

FIG. 4 is a sectional view of essential parts of a weekly pay machine which is another embodiment of the present invention, in which the same parts as in FIG. 1 are denoted by the same reference numerals.

In this case, two heat shield plates 20a and 20b are placed in the air chamber 11 in a stacked manner with a slight gap between them. The heat shield plate 20a is shown in FIG. 5, and the heat shield plate 20b is shown in FIG. The annular portion 18 of the heat shield plate 20a and the protrusion portion 19 of the heat shield plate 20b are overlapped and sandwiched between the stepped portion 13 of the turbine case 1 and the flange portion 12 of the center housing 5.

The air chamber 11 is divided into three air chambers 11a, 11b, and 11c, and the temperature rise in the center housing 5 can be further reduced. Next, we will show the experimental results when the engine was suddenly stopped. It has now been actually measured that exhaust gas of maximum 850 to 900 oo passes through the spiral passage 2 of the turbine case, and that the surface temperature of the heat shield plate 20a is approximately 800 oc and the back surface thereof is 650 qC. In addition, in that case, the heat shield plate 20b
The temperature at the left end of the center housing 5 is 350 to 400 oo, and the temperature at the left end of the center housing 5 is 30,000 or less. The bearing portion 7 at this time is 100 oo or less. The reason why the temperature rise in the bearing part 7 is reduced in this way is that the heat conduction by the two heat shield plates 20a and 20b, the convection in the air chamber 11, and the heat transfer by key radiation are efficiently suppressed. It is something.

Figures 5 and 6 are plan views of the heat shield plate in Figure 4;
A large cutout 17 is provided around the opening of the heat shield plate 20b in the figure, leaving a protrusion 19. Note that the area around the entrance (shaded area) of the heat shield plate 20a in FIG. 5 is left in place to reliably prevent exhaust gas from entering. Figure T is a diagram comparing the temperatures of the heat shield plate and the centering plate.
The temperature at 0 is approximately 450qC, and the temperature at center/using 5 is 40qC.
It is about 0qo. However, in the case of FIG. 4 using two heat shield plates 20, the temperature of the second heat shield plate 20b is 350qC.
, the temperature of the center housing 5 is about 310°C. In other words, it is better to use two heat shield plates than one heat shield plate in the center housing 5.
The temperature difference between the center housing 5 and the heat shield plate 20b having the protrusion 19 is 4
It shows that it is 0 to 5000. Therefore, the temperature of the bearing portion 7 after the bearing after the engine is stopped can be kept at 15,000 or less. The heat shield structure of this example suppresses the temperature rise of the center housing when the engine is stopped by dividing the air chamber into three parts with two heat shield plates, and prevents phosphorus on the bearing and piston rings. The effect is that deformation of the material can be prevented.

As described above, the weekly payer of the embodiment suppresses the temperature rise in the bearing part due to the stoppage of the flow of lubricating oil when the engine is stopped by reducing the contact heat transfer area between the turbine case and the center housing, thereby creating a carbon bridge. In particular, when two heat shields are provided, heat conduction through the heat shields, convection within the air chamber, and heat transfer due to facial radiation can be effectively suppressed. Therefore, the effect is even more remarkable, and the temperature rise of the center housing, especially the bearing portion, can be suppressed and smooth operation can be achieved for a long period of time.

The supercharger of the present invention has a relatively simple structure, suppresses the temperature rise of the center housing, and can provide a supercharger that can operate smoothly.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of essential parts of a supercharger that is an embodiment of the present invention.
Figure 2 is a plan view of the heat shield plate in Figure 1, Figure 3 is an enlarged view of the connection between the turbine case and center housing in Figure 1, and Figure 4 is a weekly payer according to another embodiment of the present invention. A sectional view of the main parts of
5 and 6 are plan views of the heat shield plate of FIG. 4, and FIG. 7 is a diagram comparing the temperatures of the heat shield plate and the center housing. 1... Turbine case, 2... Spiral passage, 3...
・Turbine impeller, 5...Center housing, 6...
・Rotating shaft, 7...Bearing part, 8...Oil path, 9...
Piston ring, 10, 20... Heat shield plate, 11...
Air chamber, 12...Flange part, 13...Step part, 1
4... Seat plate, 15... Bolt, 16... Oil outlet,
17... Defect part, 18... Annular part, 19... Protrusion part, 21... Iron joint surface, 22... Contact Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Figure 6 Figure 7

Claims (1)

[Claims] 1. A supercharger comprising a turbine case, a center housing that supports a rotating shaft of a turbine impeller integrally assembled with the turbine case using a bearing, and a heat shield plate installed between the turbine case and the center housing. In the machine, the center housing is hermetically fitted to the rotating shaft through a piston ring at a tip hole thereof, and a flange portion is engaged with a stepped portion of the turbine case through a peripheral portion of the heat shield plate. The heat shield plate is a dish-shaped body having a center hole, and the center hole is located in an annular space formed by the blade end surface of the turbine impeller, the inner surface of the turbine case, and the end of the center housing. A first heat shield plate that is freely held relative to the rotary blade and whose peripheral portion is clamped by the joint portion of the turbine case and the center housing, and only the protrusion portion of the peripheral portion is clamped by the engaging portion. A supercharger comprising at least the second heat shield plate among the second heat shield plates.