JPS6240095Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a turbocharger, and more particularly to a turbocharger configured to cool a bearing portion of a rotating shaft with cooling water.

Turbochargers tend to reach high temperatures due to the effects of exhaust gas, etc. Therefore, if the engine is stopped immediately after high-load operation, the lubricating oil lubricating the rotating shaft bearings will carbonize due to the heat, causing damage to the bearings. Performance may deteriorate. However, because conventional turbochargers simply circulate cooling water through a water jacket formed around the bearing, the turbine wheel side of the bearing is particularly susceptible to high temperatures due to the heat of exhaust gas being transmitted. cannot be cooled effectively.

In view of the above problems, the present invention is characterized in that the cooling water is directly sprayed onto the outer peripheral surface of the bearing.

The present invention will be explained below with reference to illustrated embodiments.

1 and 2 show a first embodiment of the invention. The turbocharger housing consists of a center housing 1 and a compressor housing 2.
and a turbine housing 3, and the center housing 1 is formed with a bearing portion 5 that pivotally supports a rotating shaft 4. The rotary shaft 4 is provided with a compressor wheel 6 at one end and a turbine wheel 7 at the other end. The compressor wheel 6 is housed in the compressor housing 2, and the turbine wheel 7 is housed in the turbine housing 3. A floating radial bearing 8 provided between the rotating shaft 4 and the bearing portion 5 is rotatable relative to the rotating shaft 4 and the bearing portion 5, and has an oil hole 9 formed in the radial direction. Therefore, the lubricating oil is supplied around the radial bearing 8 through the lubricating oil supply hole 10 formed in the center housing 1, flows around the rotating shaft 4 through the oil hole 9, and then flows through the oil drain passage 11. It is discharged to the outside.

A thrust bearing 12 is provided on the compressor wheel 6 side of the radial bearing 8. The thrust bearing 12 is fixed to the center housing 1 by a partition wall member 15, and has a runner member 1 fitted to the rotating shaft 4.
Combined with 3. A mechanical seal 16 is provided at the portion of the partition member 15 through which the rotating shaft 4 passes, to prevent lubricating oil in the center housing 1 from leaking to the compressor housing 2 side. Therefore, the lubricating oil supplied from the lubricating oil supply hole 10 is
The oil also flows into the thrust bearing 12 and is discharged from the oil drain passage 11.

A cooling chamber 17 is formed within the center housing 1 around the bearing portion 5 and is isolated from the flow path of the lubricating oil. This cooling chamber 17 has a bearing section 5.
Cooling water is supplied to cool the A supply pipe 18 for feeding the cooling water extends into the center housing 1 through a flange plate 19 attached to the wall of the center housing 1. Supply pipe 18
A water supply opening 20 formed in the side surface of the tip end faces the upper part of the bearing part 5 on the turbine wheel 7 side, so that cooling water is directly sprayed onto the bearing part 5. On the other hand, a discharge pipe 21 for discharging cooling water to the outside is attached to the wall portion on the opposite side from the flange plate 19.

Therefore, the water supply pipe 18 is connected from a water supply source (not shown).
The cooling water pumped through is ejected from the opening 20 and sprayed onto the portion of the bearing portion 5 on the turbine wheel 7 side, thereby effectively cooling this portion.

FIG. 3 shows a second embodiment, in which the supply pipe 18 and the discharge pipe 21 are both attached to a flange plate 19. Also in this example, the opening 2 of the supply pipe 18
0 faces the turbine wheel 7 side portion of the bearing portion 5, and the cooling water is directly sprayed onto this portion. Therefore, the second embodiment has the same cooling effect as the first embodiment, but since the member for attaching the discharge pipe 21 is shared with the member for attaching the supply pipe 18, it is different from the first embodiment. The number of parts can be reduced compared to the previous model.

Note that the supply pipe 18 may be opened at its distal end and curved so that the distal end faces the bearing portion 5, and the shape of the supply pipe 18 is of course not limited.

As described above, according to the present invention, the bearing portion can be effectively cooled, and the durability of the turbocharger bearing portion can be improved.

In addition, since this invention uses water as a coolant, compared to conventional methods that use lubricating oil as a coolant, the lubricating oil may carbonize and degrade its performance, and this carbonized lubricant may Oil does not clog the cooling jet holes, and the outer periphery of the bearing can be effectively cooled with low-temperature cooling water even when the engine is stopped.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a first embodiment of the present invention, FIG. 2 is a sectional view taken along the line - in FIG. 1, and FIG. 3 is a sectional view showing a second embodiment of the present invention. 4... Rotating shaft, 5... Bearing section, 6... Compressor wheel, 7... Turbine wheel, 18...
...supply pipe.

Claims (1)

[Scope of utility model registration request] In a turbocharger in which the outer peripheral surface of a bearing that supports a rotating shaft having a compressor wheel and a turbine wheel at both ends is cooled by cooling water, the cooling water is sprayed directly onto the outer peripheral surface of the bearing. Features a turbo charger.