Heat exchanger

Abstract

A heat exchanger includes an apparatus body, a motor, an air-exhaust fan casing, an air-supply fan casing, heat exchanging devices, an air-supply air-flow path, and an air-exhaust air-flow path. A first stacking pitch of heat transfer plates in the heat exchanging devices placed at positions other than that immediately after an outdoor suction port in the air-supply air-flow path and at positions other than that immediately after a indoor suction port in the air-exhaust air-flow path is smaller than a second stacking pitch of heat transfer plates in the heat exchanging devices immediately after the outdoor suction port in the air-supply air-flow path and immediately after the indoor suction port in the air-exhaust air-flow path.

1 . A heat exchanger comprising:
 an apparatus body with a box shape which is provided, in its side surfaces, with an indoor suction port, an indoor exhaust port, an outdoor suction port and an outdoor exhaust port;   a motor on which an air-exhaust blade and an air-supply blade are mounted, at a center portion of the apparatus body;   an air-exhaust fan casing provided outside the air-exhaust blade;   an air-supply fan casing provided outside the air-supply blade;   a plurality of heat exchanging devices which are placed on outer peripheral portions of the air-exhaust fan casing and the air-supply fan casing, each of the plurality of heat exchanging devices includes stacked heat transfer plates adapted to flow air streams of different temperatures along alternate ones of the stacked heat transfer plates for exchanging heat;   an air-supply air-flow path which extends from the outdoor suction port through one or more of the heat exchanging devices and the air-supply blade and communicates with the indoor exhaust port; and   an air-exhaust air-flow path which extends from the indoor suction port through one or more of the heat exchanging devices and the air-exhaust blade and communicates with the outdoor exhaust port,   wherein a first stacking pitch of the heat transfer plates in the heat exchanging devices placed at positions other than that immediately after the outdoor suction port in the air-supply air-flow path and at positions other than that immediately after the indoor suction port in the air-exhaust air-flow path is smaller than a second stacking pitch of the heat transfer plates in the heat exchanging devices immediately after the outdoor suction port in the air-supply air-flow path and immediately after the indoor suction port in the air-exhaust air-flow path.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein
 the heat transfer plates in the heat exchanging devices which are positioned in the middle of the air-supply air-flow path and in the middle of the air-exhaust air-flow path have a third stacking pitch smaller than the first stacking pitch.   
     
     
         3 . The heat exchanger according to  claim 1 , wherein
 the heat exchanging devices have different sizes in a stacking direction of the heat transfer plates.   
     
     
         4 . The heat exchanger according to  claim 1 , wherein
 a mixture of different stacking pitches is provided in the plurality of heat exchanging devices placed on the outer peripheral portions of the air-exhaust fan casing and the air-supply fan casing.   
     
     
         5 . The heat exchanger according to  claim 1 , wherein
 some of the heat exchanging devices placed on the outer peripheral portions of the air-exhaust fan casing and the air-supply fan casing are replaced with a bypass air-flow path communicating the outdoor suction port with the air-supply blade and a bypass air-flow path communicating the indoor suction port with the air-exhaust blade.   
     
     
         6 . The heat exchanger according to  claim 1 , wherein
 all of the heat exchanging devices placed on the outer peripheral portions of the air-exhaust fan casing and the air-supply fan casing are replaced with a bypass air-flow path communicating the outdoor suction port with the air-supply blade and a bypass air-flow path communicating the indoor suction port with the air-exhaust blade.   
     
     
         7 . The heat exchanger according to  claim 5 , wherein
 a filter is provided within the bypass air-flow paths for purifying air delivered to an indoor space.   
     
     
         8 . The heat exchanger according to  claim 7 , wherein
 the filter comprises a dust filter.   
     
     
         9 . The heat exchanger according to  claim 7 , wherein
 the filter comprises a deodorization filter.   
     
     
         10 . The heat exchanger according to  claim 5 , wherein
 an acoustical material is provided within the bypass air-flow paths for reducing ventilation noises in the apparatus body.   
     
     
         11 . The heat exchanger according to  claim 6 , wherein
 a filter is provided within the bypass air-flow paths for purifying air delivered to an indoor space.   
     
     
         12 . The heat exchanger according to  claim 11 , wherein
 the filter comprises a dust filter.   
     
     
         13 . The heat exchanger according to  claim 11 , wherein
 the filter comprises a deodorization filter.   
     
     
         14 . The heat exchanger according to  claim 6 , wherein
 an acoustical material is provided within the bypass air-flow paths for reducing ventilation noises in the apparatus body.   
     
     
         15 . A heat exchanger comprising:
 a box-shaped apparatus body including an indoor suction port, an indoor exhaust port, an outdoor suction port and an outdoor exhaust port on side surfaces thereof;   a motor including an air-exhaust blade and an air-supply blade mounted thereon, the motor disposed at a center portion of the apparatus body;   an air-exhaust fan casing provided outside the air-exhaust blade;   an air-supply fan casing provided outside the air-supply blade;   a plurality of bypass air-flow paths on outer peripheral portions of the air-exhaust fan casing and the air-supply fan casing, each of the plurality of bypass air-flow paths includes stacked heat transfer plates adapted to flow air streams of different temperatures along alternate ones of the stacked heat transfer plates for exchanging heat;   an air-supply air-flow path which extends from the outdoor suction port through one or more of the heat exchanging devices and the air-supply blade and communicates with the indoor exhaust port; and   an air-exhaust air-flow path which extends from the indoor suction port through one or more of the heat exchanging devices and the air-exhaust blade and communicates with the outdoor exhaust port,   wherein a first stacking pitch of the heat transfer plates in the heat exchanging devices placed at positions other than that immediately after the outdoor suction port in the air-supply air-flow path and at positions other than that immediately after the indoor suction port in the air-exhaust air-flow path is smaller than a second stacking pitch of the heat transfer plates in the heat exchanging devices immediately after the outdoor suction port in the air-supply air-flow path and immediately after the indoor suction port in the air-exhaust air-flow path.