Turbocharger with rotary bypass valve operable to selectively configure the turbine volute as single-scroll or twin-scroll

Patent metadata

Field	Value
Publication number	US-9932886-B2
Application number	US-201615046265-A
Country	US
Kind code	B2
Filing date	Feb 17, 2016
Priority date	Feb 17, 2016
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

A turbocharger has an annular bypass valve disposed in an annular portion of a bypass passage of the turbine housing. The turbine housing defines an exhaust gas chamber having separate half-annular first and second scrolls, and a portion of the bypass passage is sector-divided by a pair of dividing walls that create two 180-degree bypass sectors respectively connected to the first and second scrolls. Each dividing wall has a through-hole. The valve rotor defines a pair of valve members that close the through-holes when the bypass valve is fully closed. When the valve rotor begins to rotate toward an open position, first the valve members open the through-holes to connect the two bypass sectors, and then the bypass flow passages begin to open.

First claim

What is claimed is:

1. A turbocharger comprising:
a compressor wheel mounted within a compressor housing;
a turbine housing defining a bore extending along a longitudinal axis and defining a sector-divided volute comprising first and second scrolls each occupying 180 degrees of a full circumference about the longitudinal axis, the turbine housing further defining first and second exhaust gas inlets that are separate from each other and respectively feed exhaust gas into the first and second scrolls;
a turbine wheel disposed in the turbine housing;
the turbine housing defining an annular bypass passage surrounding the bore and arranged to allow exhaust gas in the chamber to bypass the turbine wheel, wherein a portion of the annular bypass passage adjacent the first and second scrolls is sector-divided by a pair of dividing walls located within the bypass passage and respectively disposed on diametrically opposite sides of the bore, the pair of dividing walls dividing the portion of the bypass passage into half-annular first and second bypass sectors, each of the pair of dividing walls defining a through-hole establishing fluid communication between the bypass sectors, wherein the first scroll is connected to the first bypass sector to allow exhaust gas to pass from the first scroll to the first bypass sector, and the second scroll is connected to the second bypass sector to allow exhaust gas to pass from the second scroll to the second bypass sector;
an annular bypass valve disposed in an annular portion of the bypass passage and operable when opened to allow exhaust gas to bypass the turbine wheel, the bypass valve comprising a fixed annular valve seat and an annular valve rotor that is disposed against the valve seat and is rotatable about the longitudinal axis, the valve seat defining a plurality of valve seat orifices extending axially therethrough and the valve rotor defining a plurality of valve rotor orifices extending axially therethrough, forming a plurality of orifice pairs each comprising a valve seat orifice and a corresponding valve rotor orifice, the orifices of the orifice pairs being arranged to overlap in some rotational positions of the valve rotor so as to create bypass flow passages formed by aligned portions of the valve seat orifices and valve rotor orifices,
wherein the valve rotor includes a pair of valve members structured and arranged to respectively close the through-holes in the dividing walls in a fully closed rotational position of the valve rotor so as isolate the first and second bypass sectors from each other, the bypass flow passages also being closed in the fully closed position,
wherein the valve rotor is structured such that in a first intermediate position displaced from the fully closed position the through-holes begin to open so as to permit exhaust gas to flow between the first and second bypass sectors while the bypass flow passages remain closed, and such that in a fully open position displaced further from the first intermediate position the through-holes are fully open and the bypass flow passages are fully open.

2. The turbocharger of claim 1 , wherein the valve rotor is rotatable to a second intermediate position, between the first intermediate position and the fully open position, and wherein the bypass flow passages are partially open in the second intermediate position.

3. The turbocharger of claim 1 , wherein the valve seat includes a pair of raised ribs projecting from the valve seat and abutting an opposing face of the valve rotor, the ribs being aligned with the dividing walls for preventing leakage of exhaust gas between the first and second scrolls via the bypass valve.

4. The turbocharger of claim 3 , wherein the valve seat includes a raised pad surrounding each valve seat orifice, the raised pads projecting from the valve seat and abutting the opposing face of the valve rotor for preventing leakage of exhaust gas between the first and second scrolls via the bypass valve.

Assignees

• Honeywell Int Inc

Inventors

• Lombard Alain
• Toussaint Lionel
• Groves Chris
• Tingaud Aurelien

Classifications

• F02B37/183 Primary

  Arrangements of bypass valves or actuators therefor · CPC title

• F02B37/025

  Multiple scrolls or multiple gas passages guiding the gas to the pump drive · CPC title

• F02B37/186

  Arrangements of actuators or linkage for bypass valves · CPC title

• F02B37/22 Primary

  by varying cross-section of exhaust passages or air passages {, e.g. by throttling turbine inlets or outlets or by varying effective number of guide conduits} (F02B37/24 takes precedence) · CPC title

• F05D2220/40

  in turbochargers · CPC title