Cooling system for motor vehicle

Abstract

A cooling system includes a cooling circuit, a pump, an electric fan, an electric motor connected with the electric fan, and a controller for controlling the electric motor. The pump is capable of being driven by the electric fan that receives a ram airflow generated when the motor vehicle is running. The controller controls the electric motor to be shifted between in a first operation state where electric power is supplied to the motor and in a second operation state where no electric power is supplied to the motor. The pump is driven by a rotating torque of the ram airflow and a rotating torque of the motor in the first operation state, and the pump is driven by the rotating torque generated by the ram airflow without the rotating torque of the motor in the second operation state.

1 . A cooling system for a motor vehicle comprising:
 a cooling circuit where a cooling medium is capable of flowing therein;   a pump for pressurizing the cooling medium to circulate in the cooling circuit;   an electric fan having a plurality of blade portions;   an electric motor that is connected with the electric fan to be capable of driving the electric fan to rotate, and   a controller for controlling the electric motor, wherein   the pump is capable of being driven by the electric fan that receives a ram airflow generated when the motor vehicle is running, and wherein   the controller controls the electric motor to be shifted between in a first operation state where electric power is supplied to the electric motor and in a second operation state where no electric power is supplied to the electric motor, the pump being driven by a rotating torque of the ram airflow and a rotating torque of the electric motor in the first operation state, and the pump being driven by the rotating torque generated by the ram airflow without the rotating torque of the electric motor in the second operation state.   
   
   
       2 . The cooling system according to  claim 1 , wherein
 the pump, the electric motor and the electric fan are integrally assembled as one unit.   
   
   
       3 . The cooling system according to  claim 2 , wherein
 the pump has an impeller connected with a rotary shaft of the electric motor.   
   
   
       4 . The cooling system according to  claim 2 , wherein
 the cooling circuit is a cooling circuit for cooling a water-cooled intercooler.   
   
   
       5 . The cooling system according to  claim 2 , wherein
 the cooling medium is introduced to one of an outer periphery of the electric motor and an inner side of the electric motor to cool the electric motor.   
   
   
       6 . The cooling system according to  claim 2 , further comprising:
 a rotational speed sensor for detecting a rotational speed of the electric fan, wherein   the controller controls the electric power to drive the pump, based on the rotational speed outputted from the rotational speed sensor.   
   
   
       7 . The cooling system according to  claim 2 , further comprising:
 a variable speed change mechanism arranged between the electric fan and the pump so that a rotational speed ratio thereof can be changed.   
   
   
       8 . The cooling system according to  claim 1 , wherein
 the pump has a pump-side magnet and the electric fan has a fan main body including the blade portions and provided with a fan-side magnet so that the pump and the electric fan are magnetically connected with each other.   
   
   
       9 . The cooling system according to  claim 8 , wherein
 the pump and the electric motor are radially stacked relative to each other so that a pump housing of the pump has a pump chamber surrounding an outer periphery of the electric motor, the pump and the electric motor being overlapped with each other in an axial direction thereof.   
   
   
       10 . The cooling system according to  claim 4 , wherein
 the cooling circuit is a cooling circuit for cooling a water-cooled intercooler.   
   
   
       11 . The cooling system according to  claim 4 , wherein
 the cooling medium is introduced to one of an outer periphery of the electric motor and an inner side of the electric motor to cool the electric motor.   
   
   
       12 . The cooling system according to  claim 4 , further comprising:
 a rotational speed sensor for detecting a rotational speed of the electric fan, wherein   the controller controls the electric power to drive the pump, based on the rotational speed outputted from the rotational speed sensor.   
   
   
       13 . The cooling system according to  claim 4 , further comprising:
 a variable speed change mechanism arranged between the electric fan and the pump so that a rotational speed ratio thereof can be changed.   
   
   
       14 . The cooling system according to  claim 1 , wherein
 the cooling circuit is a cooling circuit for cooling a water-cooled intercooler.   
   
   
       15 . The cooling system according to  claim 1 , wherein
 the cooling medium is introduced to one of an outer periphery of the electric motor and an inner side of the electric motor to cool the electric motor.   
   
   
       16 . The cooling system according to  claim 1 , further comprising:
 a rotational speed sensor for detecting a rotational speed of the electric fan, wherein   the controller controls the electric power to drive the pump, based on the rotational speed outputted from the rotational speed sensor.   
   
   
       17 . The cooling system according to  claim 1 , further comprising:
 a variable speed change mechanism arranged between the electric fan and the pump so that a rotational speed ratio thereof can be changed.