CLIAMS:We claim,
1. A storage tank (20) for an exhaust gas system (10), said storage tank (20) comprising:
an inlet (22) of said storage tank (20) in flow communication with an exhaust gas path (24), said inlet (22) channels exhaust gas into said storage tank (20) via a fluid inlet valve (23); characterized in that
an outlet pipe (26) of said storage tank (20) in flow communication with a turbine (28) of a turbocharger (30) via said exhaust gas path (24), said storage tank (20) supplies exhaust gas to said turbine (28) via said exhaust gas path (24) to facilitate operating said turbine (28).
2. The storage tank (20) for an exhaust gas system (10) in accordance with Claim 1 further comprising a fluid control valve (32) located in said outlet pipe (26) of said storage tank (20), said fluid control valve (32) adapted to meter exhaust gas flowing from said storage tank (20) to said turbine (28).
3. The storage tank (20) for an exhaust gas system (10) in accordance with Claim 2 wherein said fluid control valve (32) is one selected from a group comprising a ball valve, a gate valve, a check valve, a globe valve, a butterfly valve, and the like.
4. An exhaust gas circulation system (10), said exhaust gas circulation system (10) adapted to receive exhaust gas from an engine (36), said exhaust gas circulation system (10) comprising:
an exhaust gas path (24) in flow communication with an outlet of said engine (36);
an inlet (22) of a storage tank (20) in flow communication with said exhaust gas path (24) via a fluid inlet valve (23); characterized in that
an outlet pipe (26) of said storage tank (20) in flow communication with a turbine (28) of a turbocharger (30) via said exhaust gas path (24), said storage tank (20) supplies exhaust gas to said turbine (28) via said exhaust gas path (24) to facilitate operating said turbine (28).
5. The exhaust gas system (10) in accordance with Claim 4 further comprising a fluid control valve (32) in flow communication with said outlet pipe (26) of said storage tank (20), said fluid control valve (32) supplies a metered quantity of exhaust gas from said storage tank (20) to said turbine (28) to facilitate operating said turbine (28).
6. The exhaust gas system (10) in accordance with Claim 5 wherein said fluid control valve (32) is one selected from a group comprising a ball valve, a gate valve, a check valve, a globe valve, a butterfly valve, a directional control valve, and the like.
7. An engine control unit (34), said engine control unit (34) adapted to:
receive engine speed information from an engine speed sensor; and
actuate a fluid control valve (32) located in an outlet pipe (26) of a storage tank (20) in an exhaust gas system (10) in dependence of said received engine speed information in a manner such as to supply metered quantity of exhaust gas from said storage tank (20) to a turbine (28) of a turbocharger (30).
,TagSPECI:Field of the invention
[0001] This invention relates to a storage tank for supplying exhaust gas to a turbine of a turbocharger.
Background of the invention
[0002] A turbine of a turbocharger is in flow communication with an exhaust gas passage of an internal combustion engine. During engine idling and low engine operating speeds, the pressure of the exhaust gas from the internal combustion engine is insufficient to deliver sufficient power from the turbine to run the compressor of the turbocharger. In order to increase the power delivered from the turbine to run the compressor of the turbocharger at engine idling and low engine operating speeds, an auxiliary source of exhaust gas is required to be supplied to the turbine of the turbocharger.
[0003] U.S. Patent Number 6,688,269 describes an exhaust gas circulation system and method for simple and rapid introduction of EGR gas to an internal combustion engine. The exhaust gas circulation system and method includes a pump, a tank, and a valve connected to the engine. Exhaust gas is pressurized by operation of the pump under predetermined operating conditions and stored in the tank. The valve is selectively controlled to meter selected amounts of the EGR gas to the engine. The EGR tank can be separate or integrally formed within the tubing used to direct EGR gas flow.
Brief description of the accompanying drawings
[0004] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:
[0005] Figure 1 illustrates an exhaust gas circulation system in an embodiment of the invention.

Detailed description of the embodiments
[0006] Figure 1 illustrates a storage tank 20 for an exhaust gas system 10. The storage tank 20 comprises an inlet 22 of the storage tank 20 in flow communication with an exhaust gas path 24. The inlet 22 channels exhaust gas into the storage tank 20 via a fluid inlet valve 23. An outlet pipe 26 of the storage tank 20 is in flow communication with a turbine 28 of a turbocharger 30 via the exhaust gas path 24. The storage tank 20 supplies exhaust gas to the turbine 28 via the exhaust gas path 24 to facilitate operating the turbine 28.
[0007] In addition, an exhaust gas circulation system 10 is described. The exhaust gas circulation system 10 is adapted to receive exhaust gas from an engine 36. The exhaust gas circulation system 10 comprises an exhaust gas path 24 in flow communication with an outlet of the engine 36. An inlet 22 of a storage tank 20 is in flow communication with the exhaust gas path 24 via a fluid inlet valve 23. An outlet pipe 26 of the storage tank 20 is in flow communication with a turbine 28 of a turbocharger 30 via the exhaust gas path 24, wherein the storage tank 20 supplies exhaust gas to the turbine 28 via the exhaust gas path 24 to facilitate operating the turbine 28.
[0008] An engine control unit 34 is described. The engine control unit 34 is adapted to receive engine speed information from an engine speed sensor. The engine control unit actuates a fluid control valve 32 that is located in an outlet pipe 26 of a storage tank 20 in an exhaust gas system 10 in dependence of the received engine speed information in a manner such as to supply metered quantity of exhaust gas from the storage tank 20 to a turbine 28 of a turbocharger 30.
[0009] The exhaust gas circulation system 10 is coupled to an engine 36. An outlet of the engine 36 is in flow communication with an exhaust gas path 24. The exhaust gas from the engine 36 is channeled to the turbine 28 of the turbocharger 30 via the exhaust gas path 24. An inlet 22 of a storage tank 20 is in flow communication with the exhaust gas path 24. Exhaust gas from the exhaust gas path 24 is channeled into the storage tank 20 via the inlet 22.
[00010] The inlet 22 channels exhaust gas from the exhaust gas path 24 into the storage tank 20. A fluid inlet valve 23 is used to control the flow of exhaust gas from the exhaust gas path 24 into the storage tank 20 via the inlet 22. The fluid inlet valve 23 is a unidirectional valve that channels exhaust gas from the exhaust gas path 24 into the storage tank 20. Exhaust gas from the exhaust gas path 24 is channeled into the storage tank 20 until the pressure of exhaust gas within the storage tank 20 is equal to the pressure of exhaust gas in the exhaust gas path 24. When the pressure of exhaust gas in the storage tank 20 is equal to the pressure of exhaust gas in the exhaust gas path 24, the fluid inlet valve 23 closes the inlet 22 to the storage tank 20.
[00011] An outlet pipe 26 comprises a portion of the storage tank 20. A first end of the outlet pipe 26 opens into the exhaust gas path 24. The outlet pipe 26 supplies exhaust gas from the storage tank 20 to the exhaust gas path 24. A fluid control valve 32 is in flow communication with the outlet pipe 26 of the storage tank 20 and supplies a metered quantity of exhaust gas from the storage tank 20 to the turbine 28 to facilitate operating the turbine 28. The metered quantity of exhaust gas supplied to the exhaust gas path 24 is channeled to the turbine 28 of the turbocharger 30.
[00012] The principle of working of the storage tank 20 for an exhaust gas circulation system 10 is now explained as an example. Exhaust gas from the engine 36 is channeled to the storage tank 20 via the exhaust gas path 24. When the current speed of the engine 36 is high, the high pressure exhaust gas from the engine 36 flows through the fluid inlet valve 23 to fill the storage tank 20 until the pressure of the exhaust gas within the storage tank 20 is equal to the pressure of exhaust gas in the exhaust gas path 24. During engine idling conditions and at low engine speeds, the engine control unit 34 transmits an electronic signal to the fluid control valve 32 that is indicative of the current speed of the engine 36. Based on the received electronic signal from the engine control unit 34, an opening percentage of the fluid control valve 32 is varied. The opening percentage of the fluid control valve 32 is based on a current value of engine speed that is transmitted from the engine control unit 34 in the form of the electronic signal. Based on the opening percentage of the fluid control valve 32 that is controlled by the engine control unit 34, the required quantity of exhaust gas from the storage tank 20 is supplied to the turbine 28 of the turbocharger 30.
[00013] Therefore, the turbine 28 of the turbocharger 30 is supplied with excess air from the storage tank 20 beyond the exhaust gas that is supplied from the engine 36 via the exhaust gas path 24. The excess air that is supplied from the storage tank 20 to the turbine 28 is sufficient to operate the turbine 28, thereby reducing turbo lag at lower engine speeds.
[00014] The above described storage tank 20 that is integrated within the exhaust gas circulation system 10 facilitates supplying exhaust gas from the storage tank 20 to the turbine 28, thereby operating the turbine 28 at engine idling and at low engine operating speeds respectively.
[00015] It must be understood that the embodiments explained in the above detailed description is only illustrative and does not limit the scope of this invention. The scope of this invention is limited only by the scope of the claims. Many modification and changes in the embodiments aforementioned are envisaged and are within the scope of this invention.