Hybrid powertrain

Abstract

A powertrain for a vehicle is of the combined serial and parallel hybrid type. It comprises a thermal engine ( 403 ), an electric generator/motor ( 409 ) mechanically coupled to the output shaft of the engine, a clutch ( 407 ) which can connect the two portions of the output shaft rigidly to each other, and an electric motor ( 401 ) mechanically connected to the distant portion of the output shaft. Both the generator/motor ( 409 ) and the electric motor ( 401 ) can be driven by the engine to charge an electric accumulator ( 404 ) and can receive electric power therefrom to provide extra torque to the output shaft. The output shaft of the engine drives the wheels of the vehicle through a differential. A mechanical gearbox ( 406 ) connects the output shaft to the differential and wheels ( 408 ). The use of a gearbox and two electric motors significantly improves the total performance of the powertrain. In the powertrain standard components already used for driving vehicles can be used.

What is claimed:  
     
         1 . A powertrain of a vehicle having wheels, the powertrain comprising 
 a thermal engine having an output shaft, which when required can be mechanically connected to at least one of the wheels for driving the at least one of the wheels,    an energy storage,    an electric motor, which is mechanically connected to the thermal engine or to the at least one wheel and which is electrically connected to the energy storage and is supplied with electric power from the energy storage for supplying or receiving mechanical power or torque when required,    wherein at least part of filtered air from an air filter of the thermal engine is made to pass in such a way that at least part of the electric motor will obtain cooling from the filtered air.    
     
     
         2 . A powertrain according to  claim 1 , wherein at least part of the filter air is made to pass through an airgap of the electric motor.  
     
     
         3 . A powertrain according to any of claims  1 - 2 , wherein at least part of the air is made to pass along permanent magnets of the electric motor.  
     
     
         4 . A powertrain according to claims  1 - 2 , wherein at least part of the air is made to pass between windings of the electric motor.  
     
     
         5 . In a vehicle having wheels and a powertrain including a thermal engine and a electric motor for selectively driving the vehicle, the electric motor being equipped for regenerative braking, a method of cooling the electric motor comprising: 
 passing air for supply to the thermal engine through an air filter to produce filtered air;    providing at least part of filtered air from an air filter of the thermal engine to the electric motor to provide cooling thereof.