Seat air conditioning unit

Abstract

In an air conditioning unit for a seat, a duct forms a first outlet port through which air is blown to a seat surface and a second outlet port for discharging air. A heat exchanger unit having a thermoelectric effect element is disposed in the duct. An air volume control device is disposed in a duct to control a ratio of air introduced to the first outlet port to air introduced in an inlet port of the duct. In a draft mode, the air volume control device is operated such that the volume of air introduced to the first outlet port is larger than that in a normal mode. In a predetermined condition, the air volume control device is operated in the draft mode and an electric current supply to the thermoelectric effect element is controlled such that a heat exchange rate in the heat exchanger unit is smaller than that in the normal mode.

1 . An air conditioning unit for a seat for blowing air from a seat surface, comprising: 
 a duct defining an inlet port and a passage space through which air introduced in the inlet port flows, the passage space separating into a first passage and a second passage, the first passage defining a first outlet port through which air is blown to the seat surface, and the second passage defining a second outlet port through which air is discharged;    a heat exchanger unit disposed between the inlet port and the first and second outlet ports in the duct, the heat exchanger unit having a thermoelectric effect element, a first heat exchanger, and a second heat exchanger, the thermoelectric effect element including a first side and a second side, one of the first side and the second side radiating heat and the other one of the first side and the second side absorbing heat according to a flow direction of an electric current therein, the first heat exchanger disposed adjacent to the first side for performing heat exchange with air flowing in the first passage, and a second heat exchanger disposed adjacent to the second side for performing heat exchange with air flowing in the second passage; and    an air volume control device disposed in the duct for changing a ratio of air introduced to the first outlet port to the air introduced in the inlet port between a normal mode and a draft mode, wherein    in the normal mode the thermoelectric effect element is energized and the air volume control device is operated such that air passing through the first heat exchanger is introduced to the first outlet port and air passing through the second heat exchanger is introduced to and discharged from the second outlet port, and    in the draft mode the air volume control device is operated so that the ratio of air introduced to the first outlet port to the air introduced in the inlet port is larger than that in the normal mode, wherein    in a predetermined condition, the air volume control device is operated in the draft mode and an electric current supply to the thermoelectric effect element is controlled such that a heat exchange rate in the first and second heat exchangers is smaller than that in the normal mode.    
   
   
       2 . The air conditioning unit according to  claim 1 , further comprising: 
 a blower unit disposed upstream of the inlet port of the duct for producing a flow of air into the inlet port.    
   
   
       3 . The air conditioning unit according to  claim 2 , wherein in the draft mode, the blower unit is operated at a maximum level.  
   
   
       4 . The air conditioning unit according to  claim 1 , wherein the predetermined condition is satisfied when a physical value relating to a temperature of the seat surface is equal to or higher than a first predetermined value.  
   
   
       5 . The air conditioning unit according to  claim 4 , wherein 
 when the physical value is lower than the first predetermined value, the thermoelectric effect element is energized in a condition same as the normal mode, and    when the physical value is lower than a second predetermined value that is lower than the first predetermined value, the air volume control device is operated in the normal mode.    
   
   
       6 . The air conditioning unit according to  claim 4 , wherein 
 when the physical value is lower than the first predetermined value, the thermoelectric effect element is energized in a condition same as the normal mode, and    when a first predetermined time period has elapsed since the thermoelectric effect element was energized in the condition same as the normal mode, the air volume control device is operated in the normal mode.    
   
   
       7 . The air conditioning unit according to  claim 4 , wherein 
 when the physical value is lower than the first predetermined value, the air volume control device is operated in the normal mode, and the thermoelectric effect element is energized in a condition same as the normal mode.    
   
   
       8 . The air conditioning unit according to  claim 4 , wherein 
 when the physical value reduces below a third predetermined value that is lower than the first predetermined value in a condition that the air volume control device is operated in the draft mode and the electric current supply to the thermoelectric effect element is controlled such that the heat exchange rate is smaller than that of the normal mode, the air volume control device is operated in the normal mode and the thermoelectric effect element is energized in a condition same as the normal mode.    
   
   
       9 . The air conditioning unit according to  claim 4 , wherein 
 when a second predetermined time period has elapsed since the air volume control device was operated in the draft mode and the electric current supply to the thermoelectric effect element was controlled such that the heat exchange rate is smaller than that of the normal mode in a condition that the physical value is equal to or higher than the first predetermined value, the air volume control device is operated to the normal mode and the thermoelectric effect element is energized in a condition same as that in the normal mode.    
   
   
       10 . The air conditioning unit according to  claim 1 , wherein 
 the air volume control device includes a first open and close member, the first open and close member is disposed at a position upstream of the second heat exchanger to open and close the second passage to thereby control a volume of air introduced to the second outlet port, and    in the draft mode the first open and close member is operated to fully close the second passage to restrict the air from flowing to the second outlet port, to thereby increase a volume of air introduced to the first outlet port.    
   
   
       11 . The air conditioning unit according to  claim 1 , wherein 
 the air volume control device includes a first open and close member, the first open and close member is disposed to open and close the second passage at a position downstream of the second heat exchanger, when the first open and close member fully closes the second passage the air passing through the second heat exchanger is allowed to flow in the first passage, and when the first open and close member opens the second passage the air passing through the second heat exchanger is restricted from flowing in the first passage, and    in the draft mode the first open and close member is disposed to fully close the second passage to increase a volume of air introduced to the first outlet port.    
   
   
       12 . The air conditioning unit according to  claim 11 , wherein the first open and close member is formed of a material that deforms according to an ambient temperature and the second passage is open and closed according to deformation of the first open and close member.  
   
   
       13 . The air conditioning unit according to  claim 1 , wherein 
 the duct further defines a bypass passage through which air flows toward the first outlet port while bypassing the first heat exchanger and the second heat exchanger,    the air volume control device includes a second open and close member disposed to open and close the bypass passage, and    in the draft mode the second open and close member is operated to open the bypass passage so that a volume of air introduced to the first outlet port increases.    
   
   
       14 . The air conditioning unit according to  claim 13 , wherein 
 the second open and close member is disposed at a position upstream of the bypass passage.    
   
   
       15 . The air conditioning unit according to  claim 13 , wherein the first heat exchanger defines an opening that opens to the bypass passage.  
   
   
       16 . An air conditioning unit for a seat for blowing air from a seat surface, comprising: 
 a duct defining an inlet port and a passage space through which air introduced in the inlet port flows, the passage space separating into a first passage and a second passage, the first passage defining a first outlet port through which air is blown to the seat surface, the second passage defining a second outlet port through which air is discharged, the duct further defining a bypass passage that diverges from the passage space and communicates with the first outlet port of the first passage;    a heat exchanger unit disposed between the inlet port and the first and second outlet ports in the duct, the heat exchanger unit having a thermoelectric effect element, a first heat exchanger, and a second heat exchanger, the thermoelectric effect element having a first side and a second side, one of the first side and the second side radiating heat and the other one of the first side and the second side absorbing heat according to a flow direction of an electric current in the thermoelectric effect element, the first heat exchanger disposed adjacent to the first side for performing heat exchange with air passing through the first passage, the second heat exchanger disposed adjacent to the second side for performing heat exchange with air passing through the second passage; and    an air volume control device disposed in the duct for changing a volume of air flowing in the bypass passage between a normal mode and a draft mode, wherein    in the normal mode the thermoelectric effect element is energized and air passing through the first heat exchanger is introduced to the first outlet port and air passing through the second heat exchanger is discharged from the second outlet port, and    in the draft mode a ratio of air introduced to the first outlet port to the air introduced in the inlet port is larger than that in the normal mode, wherein    in the draft mode the air volume control device is operated so that a volume of air flowing through the bypass passage toward the first outlet port is larger than that in the normal mode.    
   
   
       17 . The air conditioning unit according to  claim 16 , further comprising: 
 a blower unit disposed at a position upstream of the inlet port of the duct for producing a flow of air into the inlet port.    
   
   
       18 . The air conditioning unit according to  claim 16 , wherein the bypass passage is located between the seat and the first heat exchanger, in the first passage.  
   
   
       19 . The air conditioning unit according to  claim 16 , wherein in the draft mode an electric current supply to the thermoelectric effect element is controlled such that a heat exchange rate of the first and second heat exchangers is smaller than that in the normal mode.  
   
   
       20 . The air conditioning unit according to  claim 16 , further comprising: 
 a first open and close member disposed upstream of the second heat exchanger, wherein    the first open and close member is operated to open and close the second passage for controlling a volume of air introduced to the second outlet port, and    in the draft mode the first open and close member is operated to fully close the second passage.    
   
   
       21 . The air conditioning unit according to  claim 16 , further comprising: 
 a first open and close member disposed downstream of the second heat exchanger to open and close the second passage, wherein    when the first open and close member fully closes the second passage the air passing through the second heat exchanger is allowed to flow in the first passage and is restricted from flowing to the second outlet port,    when the first open and close member opens the second passage the air passing through the second heat exchanger is restricted from flowing in the first passage, and    in the draft mode the first open and close member is disposed to fully close the second passage.    
   
   
       22 . The air conditioning unit according to  claim 21 , wherein the first open and close member is formed of a material that deforms according to an ambient temperature, and the second passage is open and closed according to deformation of the first open and close member.  
   
   
       23 . The air conditioning unit according to  claim 16 , wherein the air volume control device includes a second open and close member disposed to open and close the bypass passage, and in the draft mode, the second open and close member is operated to open the bypass passage so that a volume of air introduced to the first outlet port increases.  
   
   
       24 . The air conditioning unit according to  claim 23 , wherein the second open and close member is disposed upstream of the bypass passage.  
   
   
       25 . The air conditioning unit according to  claim 16 , wherein the first heat exchanger forms an opening that opens to the bypass passage.