Turbocharger for an internal combustion engine

• US 20110036089A1
• Filed: 08/06/2010
• Published: 02/17/2011
• Est. Priority Date: 08/06/2009
• Status: Active Grant

• Current Assignee: Schaeffler Technologies AG & Co.KG (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: Schaeffler Technologies GmbH & Co. KG (INA-Holding Schaeffler GmbH & Co. KG)
• Inventors: Englisch, Andreas, Triller, Andreas
• Granted Patent: US 8,495,875 B2
• Time in Patent Office: Days
• US Class Current: 60/608
• CPC Class Codes: F02B 37/10 at least one pump being alternatively or simultaneously driven by exhaust and other drive, e.g. by pressurised fluid from a reservoir or an engine-driven pump
• CPC Class Codes: F02B 39/02 Drives of pumps exhaust drives or combined exhaust and other drives F02B37/00; Varying pump drive gear ratio
• CPC Class Codes: F02B 39/10 electric
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A turbocharger for an internal combustion engine, in which a mechanical energy flow can be generated for a intake airflow from an exhaust gas flow of the internal combustion engine. The turbocharger includes a mechanical energy converter connected between the exhaust gas flow and the intake airflow, by which converter the mechanical energy flow can be transferred and transmitted. The turbocharger also includes an electrical energy converter associated with the mechanical energy flow for converting electrical energy into mechanical energy, or vice versa, to enable improved intake airflow charging of an internal combustion engine. By means of the electrical energy converter, an electrical energy flow can be selectively branched off to a battery or fed into the mechanical energy flow.

Claims

1. A turbocharger for an internal combustion engine, in which mechanical energy flow is generated from exhaust gas flow and is fed to intake airflow of the internal combustion engine, said turbocharger comprising:

an exhaust gas turbine positioned for receiving engine exhaust gas for providing mechanical energy;

an intake airflow compressor positioned at an engine intake airflow conduit;

a mechanical energy converter connected between the exhaust gas turbine and the intake airflow compressor for receiving mechanical energy provided by the exhaust gas turbine and for providing mechanical energy to the intake airflow compressor; and

an electrical energy converter operatively connected with the mechanical energy converter for converting mechanical energy output into electrical energy and for converting electrical energy into mechanical energy for supply to the mechanical energy converter, whereby a flow of electrical energy A turbocharger in accordance with claim 1, wherein can be selectively branched from or fed to a flow of mechanical energy.

2. A turbocharger in accordance with claim 1, wherein the mechanical energy converter includes a variable speed planetary transmission having a continuously variable transmission ratio.

3. A turbocharger in accordance with claim 2, wherein the variable speed planetary transmission includes a first transmission stage and a second transmission stage, and wherein the electrical energy converter is disposed between the first and second transmission stages.

11. An internal combustion engine including a turbocharger in accordance with claim 1.

12. An internal combustion engine in accordance with claim 11 and operative for carrying out the method in accordance with claim 4.

13. A turbocharger in accordance with claim 1, wherein the mechanical energy converter is a two-stage planetary gear transmission.

14. A turbocharger in accordance with claim 1, including a tandem turbocharger including two exhaust gas turbines and two intake airflow compressors.

15. A turbocharger in accordance with claim 14, including two respective planetary gear transmissions, wherein the intake airflow compressors are each non-rotatably connected with a sun gear of a respective planetary gear transmission.

16. A turbocharger in accordance with claim 14, wherein respective exhaust gas turbines are operatively connected with respective intake airflow compressors through respective freewheels.

4. A method for operating a turbocharger for an internal combustion engine including an exhaust gas turbine, an intake airflow compressor, a mechanical energy converter connected between the exhaust gas turbine and the intake airflow compressor, and an electrical energy converter operatively connected with the mechanical energy converter, said method comprising the steps of:

operating the turbocharger to generate mechanical energy;

supplying mechanical energy to the electrical energy converter and generating electrical energy in the electrical energy converter;

selectively branching off a flow of electrical energy from the electrical energy converter to an electrical power component during a first operating condition of the internal combustion engine; and

selectively supplying electrical energy from the electrical power component to the electrical energy converter for supplementing mechanical energy generated by the turbocharger during a second operating condition of the internal combustion engine.

5. A method in accordance with claim 4, including the step of:

steplessly transmitting mechanical energy flow to the intake airflow compressor through a variable planetary gear transmission having a continuously variable transmission ratio.

6. A method in accordance with claim 4, including the steps of:

transmitting additional mechanical energy to the intake airflow compressor when the engine rotational speed of the internal combustion engine falls below a threshold engine rotational speed by feeding a flow of electrical energy to the electrical energy converter; and

transmitting unneeded mechanical energy to the electrical energy converter when engine rotational speed of the internal combustion engine exceeds the threshold speed by branching off electrical energy flow to the electrical power component.

7. A method in accordance with claim 4, including the step of:

steplessly transmitting mechanical energy to the intake airflow compressor so that the speed of the intake airflow compressor associated with an engine intake airflow volume over an increasing speed characteristic of the internal combustion engine, relative to the speed of the exhaust gas turbine associated with the exhaust gas flow, first increases disproportionately, then increases again under-proportionately, and finally decreases slightly.

8. A method in accordance with claim 7, including the step of:

controlling a flow of electrical energy from the electrical energy converter and transmitting resulting additional mechanical energy to the exhaust gas turbine so that the exhaust gas turbine speed increases proportionally to the engine speed.

9. A method in accordance with claim 4, including at least one of the following steps:

selectively branching a flow of electrical energy from the electrical energy converter to an electrical energy accumulator;

selectively branching a flow of electrical energy from the electrical energy converter to an electrical energy source;

selectively branching a flow of electrical energy from the electrical energy converter to an electrical energy sink and

selectively branching a flow of electrical energy from the electrical energy converter to a rechargeable battery.

10. A method in accordance with claim 4, including the steps of:

controlling flow of electrical energy by the electrical control component; and

controlling operation of the electrical energy converter by the electrical control component.