Centrifugal air blower unit having movable portion

Abstract

A centrifugal air blower unit includes a centrifugal multi-blade fan, a scroll casing, and an introduction duct. The fan has a rotation axis and a plurality of blades. The scroll casing provides a first air passage. The introduction duct provides a second air passage. The fan sucks the air from the rotation axis and blows the air toward the outer circumference of the fan. The first and second air passages flow the air blown from the fan. The inner wall of the introduction duct includes a movable portion. The inner wall of the introduction duct is smoothly jointed between the first and second air passages even when the movable portion is displaced in accordance with the airflow amount of the air blown from the scroll casing.

What is claimed is:  
     
         1 . A centrifugal air blower unit for blowing an air to a heat exchanger, the unit comprising: 
 a centrifugal multi-blade fan having a rotation axis with an axial direction, an outer circumference and a plurality of blades disposed around the rotation axis of the fan;    a scroll casing for accommodating the fan and for providing a first air passage so as to flow the air by an airflow amount; and    an introduction duct having an inner wall for providing a second air passage,    wherein the fan sucks the air from the axial direction of the rotation axis and blows the air toward the outer circumference of the fan,    wherein the first air passage has a scroll shape and flows the air blown from the fan,    wherein the second air passage introduces the air blown from the scroll casing toward the heat exchanger,    wherein the inner wall of the introduction duct includes a movable portion, and    wherein the inner wall of the introduction duct is smoothly jointed between the first and second air passages even when the movable portion is displaced in accordance with the airflow amount of the air blown from the scroll casing.    
     
     
         2 . The unit according to  claim 1 , 
 wherein each of the first and second passages includes an upstream side and a downstream side, and    wherein the inner wall of the introduction duct is smoothly jointed from the upstream side to the downstream side of the first and second air passages.    
     
     
         3 . The unit according to  claim 1 , 
 wherein the movable portion includes a seal for preventing an air leakage.    
     
     
         4 . A centrifugal air blower unit for blowing an air to a heat exchanger, the unit comprising: 
 a centrifugal multi-blade fan having a rotation axis with an axial direction, an outer circumference and a plurality of blades disposed around the rotation axis of the fan;    a scroll casing with a nose for accommodating the fan and for providing a first air passage so as to flow the air by an airflow amount; and    an introduction duct having an inner wall for providing a second air passage,    wherein the fan sucks the air from the axial direction of the rotation axis and blows the air toward the outer circumference of the fan,    wherein the first air passage has a scroll shape and flows the air blown from the fan,    wherein the second air passage introduces the air blown from the scroll casing toward the heat exchanger,    wherein the inner wall of the introduction duct includes a movable portion, which connects to the nose of the scroll casing, and    wherein the inner wall of the introduction duct is smoothly jointed between the first and second air passages even when the movable portion of the inner wall of the introduction duct is displaced in accordance with the airflow amount of the air blown from the scroll casing.    
     
     
         5 . The unit according to  claim 4 , 
 wherein each of the first and second passages includes an upstream side and a downstream side, and    wherein the inner wall of the introduction duct is smoothly jointed from the upstream side to the downstream side of the first and second air passages.    
     
     
         6 . The unit according to  claim 4 , 
 wherein the movable portion includes a first movable portion and a second movable portion,    wherein the first movable portion is disposed from the nose toward the scroll casing so that the first movable portion provides a part of the scroll casing, and    wherein the second movable portion is disposed from the nose toward the heat exchanger so that the second movable portion provides a part of the introduction duct.    
     
     
         7 . The unit according to  claim 4 , 
 wherein the scroll casing includes a side wall, and    wherein the first movable portion moves along with the sidewall of the scroll casing.    
     
     
         8 . A centrifugal air blower unit for blowing an air to a heat exchanger, the unit comprising: 
 a centrifugal multi-blade fan having a rotation axis with an axial direction, an outer circumference and a plurality of blades disposed around the rotation axis of the fan;    a scroll casing with an outer periphery for accommodating the fan and for providing a first air passage so as to flow the air by an airflow amount; and    an introduction duct having an inner wall for providing a second air passage,    wherein the fan sucks the air from the axial direction of the rotation axis and blows the air toward the outer circumference of the fan,    wherein the first air passage has a scroll shape and flows the air blown from the fan,    wherein the second air passage introduces the air blown from the scroll casing toward the heat exchanger,    wherein the inner wall of the introduction duct includes a movable portion, which connects to the inner wall disposed at the outer periphery of the scroll casing, and    wherein the inner wall of the introduction duct is smoothly jointed between the first and second air passages even when the movable portion of the inner wall of the introduction duct is displaced in accordance with the airflow amount of the air blown from the scroll casing.    
     
     
         9 . The unit according to  claim 8 , 
 wherein each of the first and second passages includes an upstream side and a downstream side, and    wherein the inner wall of the introduction duct is smoothly jointed from the upstream side to the downstream side of the first and second air passages.    
     
     
         10 . An air conditioning apparatus for a passenger compartment of a vehicle, the apparatus comprising: 
 a centrifugal air blower unit according to  claim 1;     a blower mode switching device for switching a blower mode of the air to be blown into the passenger compartment; and    a controller,    wherein the controller controls the airflow amount of the air blowing from the scroll casing on the basis of an operating condition of the blower mode switching device.    
     
     
         11 . An automatically controlled air conditioning apparatus for a passenger compartment of a vehicle, the apparatus comprising: 
 a centrifugal air blower unit according to  claim 1;  and    a controller for calculating a target temperature of the air to be blown into the compartment and for controlling at least one of a blower mode of the air to be blown into the passenger compartment and an airflow amount of the air blowing from the centrifugal air blower unit on the basis of the target temperature,    wherein the controller controls the airflow of the air blowing from the scroll casing on the basis of the target temperature.