JPH0882220A - Turbo charger - Google Patents

Abstract

PURPOSE: To prevent the burning of a turbine shaft in a turbo charger auxiliary driven by an electric motor. CONSTITUTION: In a turbo charger 4 formed of an exhaust turbine 4a, a compressor 4b rotated by the exhaust turbine 4a, and an electric motor 8 connected to the turbine shaft 4c, and having a structure for supplying the oil discharged from an oil pump driven by an engine to the bearing 4d of the turbine shaft 4c as lubricating oil, the electric circuit 11 of the electric motor 8 and a battery has a pressure switch 14 for closing the electric circuit 11 by the oil pressure rise of the lubricating oil supply piping 12 of the bearing 4d of the turbine shaft 4c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbocharger for supplying charge air compressed by a compressor to the intake side of an engine.

[0002]

2. Description of the Related Art In order to eliminate turbo lag of a turbocharger, before starting the engine, an electric motor is used to increase the speed of the rotor of the turbocharger by 30,000 rpm or more to secure the boost pressure required for the turbocharger. A turbocharger that solves the problem and obtains the best air fuel consumption is provided.

In this turbocharger, a high-speed electric motor is connected to a turbine shaft via a one-way bearing clutch or an electromagnetic clutch. Before the engine starts, the electric motor continuously operates with a battery and after the engine starts, the turbine is rotated by exhaust gas. When the number exceeds the number of revolutions of the electric motor, the turbocharger becomes freer than the electric motor due to the one-way bearing clutch or the electromagnetic clutch.

[0004]

As described above, the rotor of the turbocharger is rotated at 30,000 to 50,000 revolutions per minute by the electric motor before the engine is started. The turbine shaft of such a turbocharger that rotates at a high speed is supported by bearings that supply oil discharged from an oil pump driven by the engine as lubricating oil.

However, since the oil pressure has not risen before or immediately after the engine is started, there is a risk that sufficient oil will not be supplied to the bearing of the turbine shaft and the bearing of the turbine shaft will be burned out.

An object of the present invention is to provide a turbocharger which drives an electric motor when hydraulic pressure rises to protect a bearing of a turbine shaft.

[0007]

The gist of the present invention for achieving the above object comprises an exhaust turbine, a compressor rotated by the exhaust turbine, and an electric motor connected to a turbine shaft. In a turbocharger having a structure for supplying oil discharged from a driven oil pump to a bearing of the turbine shaft as lubricating oil, an electric circuit of the electric motor and a power source is connected to an oil supply path of the bearing of the turbine shaft, A pressure switch for closing the electric circuit with a certain value of hydraulic pressure is provided.

[0008]

With the above construction, when the hydraulic pressure rises after the engine is started, the electric circuit of the electric motor is closed by the pressure switch, and the turbocharger is driven by the electric motor to protect the bearing of the turbine shaft.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is an engine, 2 is the engine 1
The intake manifold 3 on the intake side is an exhaust manifold on the exhaust side of the engine 1.

Reference numeral 4 denotes a turbocharger, which is an exhaust turbine 4a and a turbine shaft 4 by the exhaust turbine 4a.
and a compressor 4b that rotates via c,
The turbine shaft 4c is supported by a bearing 4d. The bearing 4d is supplied with oil discharged from an oil pump (not shown) driven by the engine through a lubricating oil supply pipe 12 and through a lubricating oil return pipe 13. It has a lubricating oil supply / drain structure that is returned to the oil pan.

An electric motor 8 of the turbocharger 4 is connected to a turbine shaft 4c via a connecting shaft 9, and the electric motor 8 also drives the turbocharger 4. The electric motor 8 is connected to the battery 10 via an electric circuit 11.

Exhaust turbine 4 of the turbocharger 4
The a is connected to the exhaust manifold 3 via an exhaust passage 5, and the compressor 4b of the turbocharger 4 is connected to the intake manifold 2 via an intake passage 6 and an intercooler 7.

An electric circuit 11 of the electric motor 8 and the battery 10 is connected to a lubricating oil supply pipe 12 of a bearing 4d of the turbine shaft 4c, and the electric circuit 11 is closed by a hydraulic pressure above a certain value. A pressure switch 14 is provided.

Since the present invention has the above-described structure, when the engine 1 is stopped, the oil pump is naturally not operating and the oil pressure in the lubricating oil supply pipe 12 is lowered, so that the pressure switch is operated. 14 has opened the electric circuit 11, and the electric motor 8 does not operate.

When the engine 1 is started and the oil pump is operated, a part of the oil flows from the lubricating oil supply pipe 12 to the bearing 4
The oil that has been supplied to the bearing d and has lubricated the bearing 4d is returned to the oil pan via the lubricating oil return pipe 13. Therefore, after the engine is started, when the hydraulic pressure in the lubricating oil supply pipe 12 reaches a certain value (for example, 1.5 kg / cm ² ), the pressure switch 14 closes the electric circuit 11, the electric motor 8 is operated, and the electric motor The turbocharger 4 is driven by 8.

Therefore, the turbocharger 4 is not driven by the electric motor 8 unless the oil pressure in the lubricating oil supply pipe 12 rises and the lubricating oil is being supplied to the bearing 4d of the turbine shaft 4c. It is possible to prevent the bearing 4d from burning and protect the bearing 4d.

[0017]

As described above, according to the present invention, in the turbocharger which is auxiliary driven by the electric motor, the oil pressure of the lubricating oil supplied to the bearing of the turbine shaft increases and the lubricating oil is supplied to the bearing of the turbine shaft. Since the turbocharger is driven by operating the electric motor, it has an effect of preventing burnout of the bearing of the turbine shaft that rotates at high speed.

[Brief description of drawings]

FIG. 1 is a system diagram of the device of the present invention.

[Explanation of symbols] 1 engine 2 intake manifold 3 exhaust manifold 4 turbocharger 4a exhaust turbine 4b compressor 4c turbine shaft 4d bearing 5 exhaust passage 6 intake passage 7 intercooler 8 electric motor 9 connecting shaft 10 battery 11 electric circuit 12 lubricating oil supply pipe 13 Lubricant return pipe 14 Pressure switch

Claims (1)

[Claims] 1. An exhaust turbine, a compressor rotated by the exhaust turbine, and an electric motor connected to a turbine shaft. Lubricating oil discharged from an oil pump driven by an engine to a bearing of the turbine shaft. In a turbocharger having a structure for supplying the electric power to the electric motor and a power source, a pressure switch connected to an oil supply path of a bearing of the turbine shaft and closing the electric circuit by a certain hydraulic pressure is provided. Is a turbocharger.