Exhaust gas turbine type supercharger

Claim 2

An exhaust gas turbine type supercharger having a turbine and a compressor, in which an interior of a casing receiving therein said turbine is divided into two scroll chambers (4, 5) by a partition wall (14) and an exhaust gas is supplied to said two scroll chambers to drivingly rotate said turbine and to feed an engine with the supercharged air through said compressor, said supercharger comprising a bypass passage means (7) for connecting one of said scroll chambers (4) to a portion downstream of said tui d ine, first flow rate control valve means (8, 11, 13) for controlling a flow rate of the exhaust gas passing through said bypass passage means (7) and second flow rate control valve means (10, 15, 17) for controlling a flow rate of the exhaust gas being fed to the other of said scroll chambers (5).

Claim 3

An exhaust gas turbine type supercharger as claimed in claim 1, wherein said first flow rate control valve means (8, 11, 13) decrease the flow rate of the exhaust gas passing through said bypass passage means (7) when said second flow rate control valve means (10, 15, 17) are opened.

Claim 4

An exhaust gas turbine type supercharger as claimed in claim 1, wherein said first and second flow rate control valve means are actuated by actuator means (11, 15) driving by the supercharged pressure, and said actuator means operate so as to increase the flow rates of the exhaust gas as the supercharged pressure is increased.

Claim 5

An exhaust gas turbine type supercharger for feeding an exhaust gas from cylinders of an engine to a turbine, thereby drivingly rotating the turbine to drive a compressor mounted on the same shaft as that of the turbine so that the compressor compresses an air to be fed to the cylinders of the engine, comprising: a partition wall (14) dividing a casing of said turbine into two scroll chambers (4, 5); exhaust gas flow rate control means (10, 15, 17) introducing the exhaust gas mainly into one of said scroll chambers (4) only, in a low speed/low load operation of the engine in which the supercharged pressure is lower than a first predetermined level and introducing the exhaust gas of the engine into said two scroll chambers 4 and 5) in a high speed/high load operation of the encine in which the supercharged pressure is higher than said first predetermined level; and exhaust gas bypass means (7, 8, 11, 13) discharging to a portion (9) downstream of said turbine (6) a part of the exhaust gas fed to said turbine through one of said scroll chambers when the supercharged pressure is higher than a second predetermined level.

Claim 6

An exhaust gas turbine type supercharger for feeding an exhaust gas from cylinders of an engine to a turbine, thereby drivingly rotating the turbine to drive a compressor mounted on the same shaft as that of the turbine so that the compressor compresses an air to be fed to the cylinders of the engine, comprising: a partition wall (14) dividing a casing of said turbine into two scroll chambers (4, 5); exhaust gas flow rate control means (10, 15, 17) introducing the exhaust gas mainly into one of said scroll chambers (4) only, in a low speed/low load operation of the engine in which the supercharged pressure is lower than a first predetermined level and introducing the exhaust gas of the engine into said two scroll chambers 4 and 5) in a high speed/high load operation of the encine in which the supercharged pressure is higher than said first predetermined level; and exhaust gas bypass means (7, 8, 11, 13) discharging to a portion (9) downstream of said turbine (6) a part of the exhaust gas fed to said turbine through one of said scroll chambers when the supercharged pressure is higher than a second predetermined level.

Claim 7

An exhaust gas turbine type supercharger as claimed in claim 4, wherein said exhaust gas flow rate control neans comprise an opening/closing valve (10) interposed at an inlet of the other of said scroll chambers (5) and a diaphragm type actuator (15) controlling an opening degree of said opening/closing valve (10) in response to a magnitude of said supercharged pressure.

Claim 8

An exhaust gas turbine type supercharger as claimed in claim 4, wherein said exhaust gas bypass means comprise a port (7) formed in a wall between said one of said sccroll chambers (4) and a downstream exhaust gas passage (9) of said turbine; an opening/closing valve (8) for opening and closing said port; and a diaphragm type actuator (11) for controlling an opening degree of said opening/closing valve in response to a magnitude of said superchared pressure.

Claim 9

An ehaust gas turbine type supercharger as claimed in claer 4, wherein said exhaust gas flow rate control means comprises an opening/closing valve (10) interposed at a inlet of the other of said croll chambers (5) and a diaphragm type actuator (15) for controlling an opening degree of said opening/closing valve (10) in reponse to a magnitude of said supercharged pressure and said exhaust gas bypass means comprises a port (7) formed in a wall between said one of said scroll chambers (4) and a downstream exhaust gas passage (9) of said turbine (6), an opening/closing valve (8) for opening and closing said port and a diaphragm type actuator (11) for controlling an opening degree of said last-mentioned opening/closing valve (8) in response to a magnitude of said supercharged pressure.

Claim 10

An exhaust gas turbine type supercharger as claimed in claim 7, wherein said each of said diaphragm type actuators (11, 15) comprises an ON/OFF valve (18, 19) whose opening/closing duty is controlled in accordance w - th an electrical signal responsible to said supercharged pressure and an electrical signal responsible to an engine RPM.