Centrifugal blower and air conditioner having the same

Abstract

A centrifugal blower capable of preventing generation of a swirled air stream in a space between the inner surface of a casing and a side end of a centrifugal fan, and an air conditioner having the same. The centrifugal blower includes a casing having an air inlet, an air outlet, and a bell-mouth located near the air inlet, a centrifugal fan installed in the casing, and a stream-cutoff member provided at an inner surface of the casing around the bell-mouth to prevent an air stream from being swirled in a space between the inner surface of the casing and a side end of the centrifugal fan.

1 . A centrifugal blower comprising:
 a casing having an air inlet, an air outlet, and a bell-mouth located near the air inlet;   a centrifugal fan installed in the casing; and   a ring-shaped stream-cutoff member provided at an inner surface of the casing around the bell-mouth to prevent an air stream from being swirled in a space between the inner surface of the casing and a side end of the centrifugal fan.   
   
   
       2 . The centrifugal blower according to  claim 1 , wherein the stream-cutoff member protrudes from the inner surface of the casing to be close to the side end of the centrifugal fan, and an outer diameter of the stream-cutoff member is smaller than an outer diameter of the centrifugal fan. 
   
   
       3 . The centrifugal blower according to  claim 2 , wherein the centrifugal fan is a turbo fan having an opened side end close to the stream-cutoff member. 
   
   
       4 . The centrifugal blower according to  claim 2 , wherein the stream-cutoff member includes a stream guiding plane close to the side end of the centrifugal fan, the stream guiding plane having the same width as a radial blade length of the centrifugal fan. 
   
   
       5 . The centrifugal blower according to  claim 1 , wherein the ring-shaped stream-cutoff member has a diameter and a width, and the width protrudes from the inner surface of the casing in a substantially orthogonal direction and extends close to, without touching, the side end of the centrifugal fan. 
   
   
       6 . The centrifugal blower according to  claim 1 , wherein the ring-shaped stream-cutoff member is mounted on the inner surface of the casing and substantially fills a space defined by the inner surface of the casing, and an interior surface of the bellmouth and the side end of the centrifugal fan. 
   
   
       7 . An air conditioner having a body, a heat exchanger installed in the body, and a centrifugal blower installed in the body to blow air, the centrifugal blower comprising:
 a casing having an air inlet, an air outlet, and a bell-mouth located near the air inlet;   a centrifugal fan installed in the casing; and   a stream-cutoff member provided at an inner surface of the casing near the bell-mouth to prevent an air stream from being swirled in a space between the inner surface of the casing and a side end of the centrifugal fan.   
   
   
       8 . The air conditioner according to  claim 7 , wherein the stream-cutoff member has a ring shape protruding from the inner surface of the casing to be close to the side end of the centrifugal fan, and an outer diameter of the stream-cutoff member is smaller than an outer diameter of the centrifugal fan. 
   
   
       9 . The air conditioner according to  claim 8 , wherein the centrifugal fan is a turbo fan having an opened side close to the stream-cutoff member. 
   
   
       10 . The air conditioner according to  claim 8 , wherein the stream-cutoff member includes a stream guiding plane close to the side end of the centrifugal fan, the stream guiding plane having the same width as a radial blade length of the centrifugal fan. 
   
   
       11 . The air conditioner according to  claim 8 , wherein the ring-shaped stream-cutoff member has a diameter and a width, and the width protrudes from the inner surface of the casing in a substantially orthogonal direction and extends close to, without touching, the side end of the centrifugal fan. 
   
   
       12 . The air conditioner according to  claim 8 , wherein the ring-shaped stream-cutoff member is mounted on the inner surface of the casing and substantially fills a space defined by the inner surface of the casing and an interior surface of the bellmouth and the side end of the centrifugal fan. 
   
   
       13 . A centrifugal blower comprising:
 a casing having an air inlet, an air outlet, and a bell-mouth located near the air inlet;   a centrifugal fan installed in the casing; and   means for preventing an air stream from being swirled in a space between the inner surface of the casing and a side end of the centrifugal fan.