SU878988A1 - Turbocompressor for supercharging i.c. engine - Google Patents

Description

one

The invention relates to the field of mechanical engineering, in particular, engine-building, and specifically to devices for lubricating and sealing turbo compressors of a pressurization system.

Turbochargers for pressurization of an internal combustion engine are known, comprising a corrush of turbines with gas cavities of high and low pressure, a compressor housing with air cavities of high and low pressure, a middle housing with bearings adjoining them to their ends of oil trapping cavities for less at least one ventilated cavity separated from the adjacent oil trap by means of a seal installed with a clearance relative to the shaft and the oil drain line from the oil trap; their cavities connected to the ventilated cavity with the help, and the drainage channel 1.

The advantages of such turbochargers include the presence of a ventilation cavity, which somewhat reduces the leakage of oil through the seal at an overpressure in the pressure cavity of the compressor.

The disadvantages of these turbochargers are the need for a special extraneous source of excess air pressure; high air flow through the ventilated cavity; increased oil leakage through seals at low pressures and underpressure in the high pressure air cavity.

5 The aim of the invention is to reduce oil leakage.

To achieve this, the drainage channel is designed as a jet and a ventilated cavity communicates with air and gas.

10 cavities of high pressure with the help of the air and gas channels, the gas channel cross section being twice as large as the air channel cross section and the area of the gap in the seal is 15 within the limits of these cross sections

channels, and the ratio of the cross section of the jet to

section of the air channel is made in

within 0.1-0.5.

The ventilated cavity can be extended (3 complete in the form of two sections interconnected, one of which is adjacent to the KOMinpeccopa body and connected to the air channel, the second to the turbine body and connected to the gas channel, and

25, the seals between the sections and the oil-separating cavities may be made axially.

The drawing shows schematically 30 of the proposed turbocharger.

The turbocharger comprises a turbine housing 1 with high pressure gas cavities 2 and a low pressure cavity 3 separated from one another by an impeller 4, a compressor corus 5 with a high pressure air cavity 6 and a low pressure cavity 7 separated from one another by a compressor 8. In the middle housing 9, rotor bearings 10 are installed, made in the form of a monolithic bush I. The oil catch cavities 12 and 13 adjoin the ends of the bearings, each of which is assisted, and the axial diagonal seal 14 and 15 are separated from one of the sections 16, 17 of the ventilated cavity. The sections are communicated between themselves, with the aid of, and the sheath, its crankcase 18 and the nozzle 20 of the oil drain line connected to the oil-collecting cavity with the aid of the clearing and the branched drain channel 21 is connected to the jet 19 via the nozzle and the branched drain channel 21. A high-pressure air and gas cavity, section 16 of this cavity, adjacent to compressor case 5, is connected to air channel 22, and section 17, adjacent to turbine case 1, is connected to gas channel 23. The gas channel 23 is made in two times the air section of the canal 22. Seals 14 and 15 are mounted on the shaft with a gap relative to the housing. The area of the gap is larger than the cross section of the air channel, and smaller than the cross section of the gas channel. A channel 24 is provided for supplying oil to the bearings.

In the course of engine operation, the oil from the bearings through the oil-catching cavities 12 and 13 and the drain channel 21 is discharged into the pipe 2U of the drain line. When the engine is operating under pressure, pressure in cavity 6 of the compressor is usually greater than pressure in cavity 2 of the turbine, so air from cavity 6 of compressor goes through channel 23 to section 16 of the ventilated cavity and to crankcase 18. Most of this air is displaced through the gaps in the seals it prevents oil leakage, and a small part through the nozzle 19 enters the oil drain line. The overpressure in the ventilated cavity is determined by the pressure in the high-pressure air cavity and the ratio of the flow sections for its entry into and out of the cavity. If the overpressure in the ventilated cavity when the engine's operating mode changes becomes less than in the high-pressure gas cavity 2, this cavity is fed through the gases through channel 23. When the engine starts to idle or with low load, the pressure in the high-pressure air cavity becomes less than pressure in a high pressure gas cavity and may even become negative. In this case, both sections of the ventilated cavity are filled with gases. Since the cross section of the channel 23 is larger than the cross section of the channel 22 and more. The gap area in the seals in both sections of the ventilated cavity is always maintained with overpressure. This ensures the efficiency of the seals and reduces oil leakage.

Oil that may leak into the ventilated cavity is removed to the oil drain line through the jet. Precisional Seal Profile

increases the efficiency of their work.

Claims (2)

1. Turbocharger for pressurization of an internal combustion engine, comprising a turbine casing with high and low pressure gas cavities, a compressor casing with high and low pressure air cavities, a middle case with bearings adjacent to their ends with oil trap cavities, at least one ventilated a cavity separated from the adjacent oil catcher by means of a seal installed on the shaft with a clearance relative to the housing, and an oil drain line from the oil catcher cavities connected to the the cavity being diluted by means of a drainage channel, characterized in that that, in order to reduce oil leaks, the drip channel is made in the form of a nozzle and a ventilated cavity. It is connected to the air and gas cavities of high pressure with the help of air and gas channels, the gas channel section was filled to twice the air channel section and the value the area of the gap in the seal made within the values of the cross section of these channels, and the ratio of the cross section jet: To the section of the air channel is made in the range of 0.1-0.5. 2. Turbocharger according to claim 1, characterized in that the ventilated cavity is made in the form of two communicated between the sections, one of which is adjacent to the compressor housing, is connected to the air channel, the second is connected to the turbine housing and connected to the gas channel, and the seals between the sections and the oil trap cavities are made diagonal. Sources of information taken into account in the examination 1. French Patent No. 22134) 4, cl. F 02В 39/14, published 1974.  J