Plate-type heat exchanger, heat pump device, and heat-pump-type cooling and heating hot-water supply system

Abstract

A plate-type heat exchanger includes a plurality of heat transfer plates stacked on top of each other, a flow passage, formed by each space between the plurality of heat transfer plates, through which a fluid flows in a first direction; an inner fin disposed in the flow passage, a first projecting portion provided on an inflow side of each of the heat transfer plates and configured to prevent the fluid from flowing into gaps between both ends of the inner fin in a second direction and both ends of the heat transfer plate in the second direction, and a second projecting portion formed on an outflow side of each of the heat transfer plates and configured to perform positioning in placing the inner fin into the heat transfer plate. The first direction is a direction of flow of the fluid through the flow passage.

1 . A plate-type heat exchanger comprising:
 a plurality of heat transfer plates stacked on top of each other;   a flow passage, formed by each space between the plurality of heat transfer plates, through which a fluid flows in a first direction;   an inner fin disposed in the flow passage;   a first projecting portion provided on an inflow side of each of the heat transfer plates and configured to prevent the fluid from flowing into gaps between both ends of the inner fin in a second direction and both ends of the heat transfer plate in the second direction; and   a second projecting portion formed on an outflow side of each of the heat transfer plates and configured to perform positioning in placing the inner fin into the heat transfer plate,   the first direction being a direction of flow of the fluid through the flow passage,   the second direction being a direction orthogonal to the first direction,   the inner fin being disposed between the first projecting portion and the second projecting portion.   
     
     
         2 . The plate-type heat exchanger of  claim 1 , wherein
 the inner fin includes an offset fin having a corrugated portion formed in a corrugated shape by alternately coupling, in the second direction, vertical walls oriented perpendicularly to the heat transfer plate and horizontal walls oriented parallel to the heat transfer plate, and   a width of the first projecting portion in the second direction is twice or more and five times or less as great at a distance between two adjacent ones of the vertical walls of the inner fin.   
     
     
         3 . The plate-type heat exchanger of  claim 2 , wherein a width of the second projecting portion in the second direction is twice or more and five times or less as great as the distance between the two adjacent vertical walls of the inner fin. 
     
     
         4 . The plate-type heat exchanger of  claim 1 , wherein the second projecting portion includes second projecting portions provided at both ends of the outflow side of the heat transfer plate in the second direction. 
     
     
         5 . The plate-type heat exchanger of  claim 1 , wherein the first projecting portion and the second projecting portion are provided to project toward the flow passage from one of two of the heat transfer plates forming the flow passage. 
     
     
         6 . The plate-type heat exchanger of  claim 5 , wherein the first projecting portion and the second projecting portion are joined to an other one of the two heat transfer plates forming the flow passage. 
     
     
         7 . The plate-type heat exchanger of  claim 1 , wherein
 the flow passage includes a first flow passage and a second flow passage alternately formed in a direction of stacking of the heat transfer plates, and   the first projecting portion and the second projecting portion include a first projecting portion and a second projecting portion provided in the first flow passage and a first projecting portion and a second projecting portion provided in the second flow passage.   
     
     
         8 . The plate-type heat exchanger of  claim 7 , wherein
 the direction of flow of the fluid through the first flow passage and the direction of flow of the fluid through the second flow passage are opposite to each other, and   the first projecting portion of the first flow passage and the second projecting portion of the second flow passage are identical in shape to each other and are in contact with each other with an overlap in location in the second direction in a cross-section perpendicular to the direction of stacking.   
     
     
         9 . The plate-type heat exchanger of  claim 7 , wherein
 the direction of flow of the fluid through the first flow passage and the direction of flow of the fluid through the second flow passage are opposite to each other, and   the second projecting portion of the first flow passage and the first projecting portion of the second flow passage are identical in shape to each other and are in contact with each other with an overlap in location in the second direction in a cross-section perpendicular to the direction of stacking.   
     
     
         10 . The plate-type heat exchanger of  claim 1 , wherein
 each of the heat transfer plates has a flat portion on which the inner fin is disposed,   the first projecting portion includes first projecting portions provided at both ends of the flat portion in the second direction and within an area surrounded by a first line representing an inflow edge of both edges of the inner fin in the first direction, two second lines representing both edges of the flat portion in the second direction, and two circular arcs at both ends of the flat portion in the second direction,   each of the two circular arcs is a circular arc with a radius R centered at a point of intersection of the first line and a corresponding one of the second lines, and   the radius R is three times as great as a flow passage height of the flow passage.   
     
     
         11 . The plate-type heat exchanger of  claim 10 , wherein
 the second projecting portion includes second projecting portions provided at both ends of the flat portion in the second direction and within an area surrounded by a third line representing an outflow edge of both edges of the inner fin in the first direction, the two second lines, and two circular arcs at both ends of the flat portion in the second direction,   each of the two circular arcs is a circular arc with a radius R centered at a point of intersection of the third line and a corresponding one of the second lines, and   the radius R is three times as great as a flow passage height of the flow passage.   
     
     
         12 . The plate-type heat exchanger of  claim 1 , wherein
 one of two of the heat transfer plates forming the flow passage is provided with the second projecting portion and the first projection portion projecting toward the flow passage,   an other one of the two heat transfer plates has a first depressed portion and a second depressed portion located opposite the first projecting portion and the second projection portion, depressed toward the flow passage, and formed in contact with the second projecting portion and the first projecting portion.   
     
     
         13 . The plate-type heat exchanger of  claim 12 , wherein points of contact between the first projecting portion of one of the heat transfer plates and the second depressed portion of the other one of the heat transfer plates are joined and points of contact between the second projecting portion of one of the heat transfer plates and the first depressed portion of the other one of the heat transfer plates are joined. 
     
     
         14 . The plate-type heat exchanger of  claim 12 , wherein
 the flow passage includes a first flow passage and a second flow passage alternately formed in a direction of stacking of the heat transfer plates,   the direction of flow of the fluid through the first flow passage and the direction of flow of the fluid through the second flow passage are opposite to each other,   the first projecting portion of one of the heat transfer plates and the second projecting portion of the other one of the heat transfer plates are different in shape from each other, and are different in location in the second direction in a cross-section perpendicular to the direction of stacking.   
     
     
         15 . The plate-type heat exchanger of  claim 12 , wherein
 the flow passage includes a first flow passage and a second flow passage alternately formed in a direction of stacking of the heat transfer plates,   the direction of flow of the fluid through the first flow passage and the direction of flow of the fluid through the second flow passage are opposite to each other,   the second projecting portion of one of the heat transfer plates and the first projecting portion of the other one of the heat transfer plates are different in shape from each other, and are different in location in the second direction in a cross-section perpendicular to the direction of stacking.   
     
     
         16 . The plate-type heat exchanger of  claim 1 , wherein each of the heat transfer plates includes two plates partially joined to each other. 
     
     
         17 . The plate-type heat exchanger of  claim 1 , wherein
 each of the heat transfer plates has header portions formed at both ends thereof in the first direction, and   each of the header portions has a projecting and depressed structure formed to bring about improvement in strength.   
     
     
         18 . The plate-type heat exchanger of  claim 17 , wherein
 the projecting and depressed structure has a plurality of circular depressed portions provided in one of two of the heat transfer plates forming the flow passage and a plurality of circular projecting portions provided in an other one of the two heat transfer plates to face the plurality of depressed portions,   each of the depressed portions and a corresponding one of the projecting portions are joined to each other,   the projecting and depressed structure is not formed at least in areas extending over a distance δ from both ends of the inner fin in the first direction, and   the distance δ is equal to or greater than an equivalent diameter of a cross-sectional shape obtained by cutting a junction between the depressed portion and the projecting portion along a surface perpendicular to the first direction through a center of the junction.   
     
     
         19 . A heat pump device comprising a refrigerant circuit in which a compressor, the plate-type heat exchanger of  claim 1 , a decompression device, and a heat exchanger are connected and through which refrigerant circulates. 
     
     
         20 . A heat-pump-type cooling and heating hot-water supply system comprising a heat medium circuit in which the heat pump device of  claim 19 , the plate-type heat exchanger, a cooling and heating hot-water supply device configured to perform cooling and heating and supply hot water, and a pump are connected and through which a heat medium circulates.