Cooling unit

Abstract

A cooling unit includes a motor, a driving shaft, a first fan, a second fan, and a fan shroud. The driving shaft extends from the motor and is disposed parallel to a core of a heat exchanger. The first fan is disposed to oppose the core for generating air for cooling the core. The first fan has a first rotation shaft connected to the driving shaft through a gear such that the first fan is rotated by the driving shaft. The fan shroud is configured to support the first fan and conduct the air from the core to the first fan. The second fan has a second rotation shaft disposed coaxial with the driving shaft and rotatable with the driving shaft. The second fan is rotated by the driving shaft when the first fan is rotated, thereby to supply the motor with air for cooling the motor.

1 . A cooling unit for generating air for cooling a core of a heat exchanger, comprising:
 a motor;   a driving shaft extending from the motor, the driving shaft to be disposed parallel to the core;   a first fan to be opposed to the core for generating the air for cooling the core, the first fan having a first rotation shaft connected to the driving shaft through a gear to be rotated by the driving shaft;   a fan shroud supporting the first fan and configured to conduct the air from the core toward the first fan; and   a second fan having a second rotation shaft and configured to generate air for cooling the motor, wherein   the second rotation shaft is disposed coaxial with the driving shaft and rotatable with the driving shaft such that the second fan is rotated by the driving shaft when the first fan is rotated.   
   
   
       2 . The cooling unit according to  claim 1 , wherein
 the driving shaft includes a first shaft part and a second shaft part,   the first shaft part is directly connected to the motor, and   the second shaft part is connected to the first rotation shaft of the first fan through the gear,   the cooling unit further comprising:   a joint coaxially coupling the first shaft part and the second shaft part.   
   
   
       3 . The cooling unit according to  claim 2 , wherein
 the second fan has a boss part forming the second rotation shaft and blades extending from the boss part, and   the joint is integrally formed into the boss part.   
   
   
       4 . The cooling unit according to  claim 1 , further comprising:
 a case housing the motor therein, wherein   the case has an air inlet opening through which air is drawn to an inside of the case by rotation of the second fan and an air outlet opening through which air is discharged from the inside of the case, and   the air outlet opening is provided downstream of the second fan with respect to a flow of air generated by the second fan and upstream of the first fan with respect to a flow of air generated by the first fan, the air outlet opening allowing communication between the inside of the case and a negative pressure region of the first fan.   
   
   
       5 . The cooling unit according to  claim 4 , wherein
 the air outlet opening is a first air outlet opening, and   the case has a second air outlet opening provided downstream of the second fan with respect to the flow of air generated by the second fan and downstream of the first fan, the second air outlet opening allowing communication between the inside of the case and a downstream location of the first fan.   
   
   
       6 . The cooling unit according to  claim 1 , wherein the second fan includes a centrifugal fan. 
   
   
       7 . The cooling unit according to  claim 1 , further comprising:
 a case housing the motor therein, wherein   the motor is connected to an end of the driving shaft and is located immediately downstream of the heat exchanger, and   the case has an air inlet opening on an axial end thereof opposite to the driving shaft for drawing air into the case.   
   
   
       8 . The cooling unit according to  claim 7 , wherein
 the air inlet opening is formed on an entirety of the axial end of the case.   
   
   
       9 . The cooling unit according to  claim 1 , further comprising:
 a control device adapted to control an operation of the second fan; and   a case housing the control device, the motor and the second fan therein, wherein   the case has a separation wall separating a first space where the control device is disposed from a second space where the motor is disposed,   the case further has an air inlet opening through which air is suctioned in the case by rotation of the second fan, and   the first space is located upstream of the second space with respect to a flow of the air suctioned from the air inlet opening.   
   
   
       10 . The cooling unit according to  claim 1 , wherein
 the first fan is one of a plurality of first fans aligned in a direction parallel to the core,   the driving shaft is disposed parallel to the core downstream of the first fans with respect to a flow of the air generated by the first fans.   
   
   
       11 . The cooling unit according to  claim 1 , further comprising:
 a case housing the motor and the second fan therein, wherein the case is integrally formed with the fan shroud.