Supercharged internal combustion engine

Abstract

A supercharged internal combustion engine includes a motor unit having a head and an exhaust manifold. A turbocharger assembly is fluid dynamically connected to the exhaust manifold, wherein the turbocharger assembly includes a turbine, a central body and a compressor. The turbocharger assembly includes a lubrication channel for the passage of a lubricating fluid hydraulically connected to a lubrication circuit of the motor unit of said internal combustion engine. The turbine includes a jacket, provided at least in part in a body thereof, arranged for the passage of a cooling fluid and in hydraulic communication with an inlet channel and an outlet channel hydraulically connected to a cooling circuit of the motor unit of said internal combustion engine. The inlet channel, outlet channel and lubrication channel are integrated in said turbocharger assembly in correspondence of a connection interface between said turbocharger assembly and the motor unit.

The invention claimed is: 
     
       1. A supercharged internal combustion engine comprising:
 a motor unit including a head and an exhaust manifold, 
 a turbocharger assembly fluid dynamically connected to said exhaust manifold, wherein said turbocharger assembly includes a turbine, a central body and a compressor, 
 wherein: 
 said turbocharger assembly comprises a lubrication channel for the passage of a lubricating fluid hydraulically connected to a lubrication circuit of said motor unit of said internal combustion engine, 
 said turbine comprises a jacket, provided at least in part in a body thereof, arranged for the passage of a cooling fluid and in hydraulic communication with an inlet channel and an outlet channel hydraulically connected to a cooling circuit of said motor unit of said internal combustion engine, 
 said inlet channel, outlet channel and lubrication channel being integrated in said turbocharger assembly in correspondence of a connection interface between said turbocharger assembly and said motor unit of said internal combustion engine 
 said turbocharger assembly comprises a stator assembly including the body of said turbine, said central body and a body of said compressor, 
 said central body comprises a cavity wherein a rotor assembly of said turbocharger assembly is housed, 
 said rotor assembly comprises a first impeller rotatably mounted within the body of said turbine, a healing bearing pack, and a second impeller rotatably mounted in the body of said compressor, wherein said first and said second impellers are connected in rotation by means of a shaft, 
 said exhaust manifold integrally cast in said turbocharge assembly, 
 at least part of said stator assembly is integral with said head,
 said stator assembly comprises a first semi-shell integrally cast with said head and a second semi-shell separable from said first semi-shell, said connection interface between the turbocharger assembly and the motor unit being a surface which separates the first semi-shell from the head, 
 the body of said turbine comprises a first and a second portion, said body of said compressor comprises a body including a first and a second portion, said central body comprises a first portion and a second portion, 
 the first portion of the body of said turbine, the first portion of the body of said compressor and the first portion of the central body are integral with each other and define said first semi-shell, 
 the second portion of the body of said turbine, the second portion of the body of said compressor and the second portion of said central body are integral with each other and define said second semi-shell, 
 
 said jacket and said lubrication channel are provided in part in said first semi-shell and in part in said second semi-shell, wherein each portion of the jacket is hydraulically connected to a respective portion provided on the other semi-shell when the first and the second semi-shells are joined together, 
 said bearing pack comprises a sleeve including annular grooves in hydraulic communication, by means of radial channels with an internal cavity provided in said sleeve, wherein said shaft is inserted in said internal cavity rotatably supported by a bushing, and 
 wherein said rotor assembly is arranged for the insertion in axial direction into said turbocharger assembly. 
 
     
     
       2. The internal combustion engine according to  claim 1 , wherein:
 said stator assembly comprises a first semi-shell integral with said head and a second semi-shell separable from said first semi-shell,   the body of said turbine comprises a first and a second portion, said compressor comprises a body including a first and a second portion, said central body comprises a first and a second portion,   the first portion of the body of said turbine, the first portion of the body of said compressor and the first portion of the central body are integral with each other and define said first semi-shell,   the second portion of the body of said turbine, the second portion of the body of said compressor and the second portion of said central body are integral with each other and define said second semi-shell,   said jacket and said lubrication channel are provided in part in said first semi-shell and in part in said second semi-shell.   
     
     
       3. The internal combustion engine according to  claim 1 , A supercharged internal combustion engine comprising:
 a motor unit including a head and an exhaust manifold, 
 a turbocharger assembly fluid dynamically connected to said exhaust manifold, wherein said turbocharger assembly includes a turbine, a central body and a compressor, 
 wherein: 
 said turbocharger assembly comprises a lubrication channel for the passage of a lubricating fluid hydraulically connected to a lubrication circuit of said motor unit of said internal combustion engine, 
 said turbine comprises a jacket, provided at least in part in a body thereof, arranged for the passage of a cooling fluid and in hydraulic communication with an inlet channel and an outlet channel hydraulically connected to a cooling circuit of said motor unit of said internal combustion engine, 
 said inlet channel, outlet channel and lubrication channel being integrated in said turbocharger assembly in correspondence of a connection interface between said turbocharger assembly and said motor unit of said internal combustion engine 
 said turbocharger assembly comprises a stator assembly including the body of said turbine, said central body and a body of said compressor, 
 said central body comprises a cavity wherein a rotor assembly of said turbocharger assembly is housed, 
 said rotor assembly comprises a first impeller rotatably mounted within the body of said turbine, a bearing pack, and a second impeller rotatably mounted in the body of said compressor, wherein said first and said second impellers are connected in rotation by means of a shaft, 
 said exhaust manifold integrally cast in said turbocharger assembly, 
 at least part of said stator assembly is integral with said head,
 said stator assembly comprises a first semi-shell integrally cast with said head and a second semi-shell separable from said first semi-shell, said connection interface between the turbocharger assembly and the motor unit being a surface which separates the first semi-shell from the head, 
 the body of said turbine comprises a first and a second portion, said compressor comprises a body including a first and a second portion, said central body comprises a first portion and a second portion, 
 the first portion of the body of said turbine, the first portion of the body of said compressor and the first portion of the central body are integral with each other and define said first semi-shell, 
 the second portion of the body of said turbine, the second portion of the body of said compressor and the second portion of said central body are integral with each other and define said second semi-shell, 
 
 said jacket and said lubrication channel are provided in part in said first semi-shell and in part in said second semi-shell, wherein each portion of the jacket is hydraulically connected to a respective portion provided on the other semi-shell when the first and the second semi-shells are joined together, 
 said bearing pack comprises a sleeve including annular grooves in hydraulic communication, by means of radial channels with an internal cavity provided in said sleeve, wherein said shaft is inserted in said internal cavity rotatably supported by a bushing, 
 wherein said rotor assembly is arranged for the insertion in axial direction into said turbocharger assembly, and 
 wherein the entire stator assembly of said turbocharger assembly is integral with said head. 
 
     
     
       4. The internal combustion engine according to  claim 1 , wherein said compressor comprises an inlet port in correspondence of which there is mounted a sleeve having an internal channel and a fastening flange rigidly connected to a body of said compressor. 
     
     
       5. A method for manufacturing an internal combustion engine, the method comprising:
 providing a motor unit including a head and an exhaust manifold,   fluid dynamically connecting the exhaust manifold to a turbocharger assembly, the exhaust manifold integrally cast in the turbocharger assembly, and the turbocharger assembly including a turbine, a central body and a compressor,   a lubrication channel of the turbocharger assembly allowing passage of a lubricating fluid hydraulically connected to a lubrication circuit of the motor unit of the internal combustion engine,   the turbine comprising a jacket at least in part in a body of the turbine, the jacket arranged for the passage of a cooling fluid and in hydraulic communication with an inlet channel and an outlet channel hydraulically connected to a cooling circuit of the motor unit of the internal combustion engine,   the inlet channel, outlet channel and lubrication channel being integrated in said turbocharger assembly in correspondence of a connection interface between the turbocharger assembly and the motor unit of the internal combustion engine,   a stator assembly of the turbocharger assembly including the body of the turbine, the central body and a body of the compressor,   joining a first semi-shell of the stator assembly to a second semi-shell of the stator assembly, the second semi-shell separable from the first semi-shell, and the first semi-shell integrally cast with said head, wherein the connection interface between the turbocharger assembly and the motor unit being a surface which separates the first semi-shell from the head,   machining a central cavity of the body of the compressor to obtain a combination of surface finishing and geometric tolerances required for insertion of the rotor assembly into the central cavity,   said rotor assembly comprising a first impeller rotatably mounted within the body of said turbine, and a second impeller rotatably mounted in the body of said compressor, said first and said second impellers connected in rotation by means of a shaft,   inserting the rotor assembly into the cavity along a rotation axis of the first and second impeller, the rotor assembly being pre-mounted upon insertion,   securing the rotor assembly into position; and   wherein the body of said turbine comprises a first and a second portion, the body of the compressor comprises includes a first and a second portion, said central body comprises a first portion and a second portion,   the first portion of the body of said turbine, the first portion of the body of the compressor and the first portion of the central body are integral with each other and define the first semi-shell, and   the second portion of the body of the turbine, the second portion of the body of the compressor and the second portion of the central body are integral with each other and define the second semi-shell.   
     
     
       6. The method of claim 5 wherein the jacket and the lubrication channel are provided in part in the first semi-shell and in part in the second semi-shell, wherein each portion of the jacket is hydraulically connected to a respective portion provided on the other semi-shell when the first and the second semi-shells are joined together. 
     
     
       7. The method of claim 6 wherein the stator comprises a bearing pack, the bearing pack comprises a sleeve including annular grooves in hydraulic communication, by means of radial channels with an internal cavity provided in the sleeve, wherein the shaft is inserted in the internal cavity rotatably supported by a bushing. 
     
     
       8. The method of claim 5 wherein the joining comprises temporarily joining the first semi shell and the second semi shell, and further comprising temporarily separating the first semi shell and the second semi shell to allow removing a chip resulting from the machining prior to inserting the rotor assembly into the cavity of the central body, and subsequently fastening the first and second semi shells together. 
     
     
       9. The method of claim 5 wherein the securing the rotor assembly into position comprises axially blocking the rotor assembly inside the cavity by inserting a pin or a threaded dowel into a first hole in the central body and a second hole in a bearing pack of the stator. 
     
     
       10. A method for manufacturing an internal combustion engine, the method comprising:
 providing a motor unit including a head and an exhaust manifold,   fluid dynamically connecting the exhaust manifold to a turbocharger assembly, the exhaust manifold integrally cast in the turbocharger assembly, and the turbocharger assembly including a turbine, a central body and a compressor,   a lubrication channel of the turbocharger assembly allowing passage of a lubricating fluid hydraulically connected to a lubrication circuit of the motor unit of the internal combustion engine,   the turbine comprising a jacket at least in part in a body of the turbine, the jacket arranged for the passage of a cooling fluid and in hydraulic communication with an inlet channel and an outlet channel hydraulically connected to a cooling circuit of the motor unit of the internal combustion engine,   the inlet channel, outlet channel and lubrication channel being integrated in said turbocharger assembly in correspondence of a connection interface between the turbocharger assembly and the motor unit of the internal combustion engine,   a stator assembly of the turbocharger assembly including the body of the turbine, the central body and a body of the compressor,   joining a first semi-shell of the stator assembly to a second semi-shell of the stator assembly, the second semi-shell separable from the first semi-shell, and the first semi-shell integrally cast with said head, wherein the connection interface between the turbocharger assembly and the motor unit being a surface which separates the first semi-shell from the head,   machining a central cavity of the central body of the compressor to obtain a combination of surface finishing and geometric tolerances required for insertion of the rotor assembly into the central cavity,   the rotor assembly comprising a first impeller rotatably mounted within the body of said turbine, a bearing pack, and a second impeller rotatably mounted in the body of said compressor, said first and said second impellers connected in rotation by means of a shaft,   inserting the rotor assembly into the cavity along a rotation axis of the first and second impeller, the rotor assembly being pre-mounted upon insertion,   securing the rotor assembly into position;   wherein the body of said turbine comprises a first and a second portion, the body of the compressor comprises includes a first and a second portion, said central body comprises a first portion and a second portion,   the first portion of the body of said turbine, the first portion of the body of the compressor and the first portion of the central body are integral with each other and define the first semi-shell, and   the second portion of the body of the turbine, the second portion of the body of the compressor and the second portion of the central body are integral with each other and define the second semi-shell, and   the entire stator assembly of the turbocharger assembly is formed integral with the head.   
     
     
       11. The method of claim 10 further comprising removing a chip resulting from the machining prior to inserting the rotor assembly into the cavity of the central body. 
     
     
       12. The method of claim 10 wherein securing the rotor assembly into position comprises axially blocking the rotor assembly inside the cavity by inserting a pin or a threaded dowel into a first hole in the central body and a second hole in a bearing pack of the rotor assembly. 
     
     
       13. The method of claim 10 wherein the jacket and the lubrication channel are provided in part in the first semi-shell and in part in the second semi-shell, wherein each portion of the jacket is hydraulically connected to a respective portion provided on the other semi-shell when the first and the second semi-shells are joined together. 
     
     
       14. The method of claim 13 wherein the stator comprises a bearing pack, the bearing pack comprises a sleeve including annular grooves in hydraulic communication, by means of radial channels with an internal cavity provided in the sleeve, wherein the shaft is inserted in the internal cavity rotatably supported by a bushing.