Plate heat exchanger and refrigeration air conditioner

Abstract

It is aimed to enhance the strength of a plate heat exchanger while maintaining the heat exchange capability of the plate heat exchanger. A plate heat exchanger 20 is configured with a plurality of stacked plates 2 and 3 . Each of the plates 2 and 3 includes at four corners thereof a first inlet hole 5 which acts as an inlet for a first fluid, a first outlet hole 6 which acts as an outlet for the first fluid, a second inlet hole 7 which acts as an inlet for a second fluid, and a second outlet hole 8 which acts as an outlet for the second fluid. Each of the plates 2 and 3 and an adjacent plate define therebetween a first flow path for passing the first fluid and a second flow path for passing the second fluid, so as to exchange heat between the first fluid and the second fluid. In each of the plates 2 and 3 , a longitudinal length L 1 is 4 or more times a lateral length L 2.

1 . A plate heat exchanger configured with a plurality of stacked plates,
 wherein each plate of the plurality of stacked plates includes:   a first inlet hole which acts as an inlet for a first fluid, the first inlet hole being located near one edge in a longitudinal direction;   a first outlet hole which acts as an outlet for the first fluid, the first outlet hole being located near another edge opposite from the first inlet hole in the longitudinal direction;   a second inlet hole which acts as an inlet for a second fluid, the second inlet hole being located near one edge in the longitudinal direction; and   a second outlet hole which acts as an outlet for the second fluid, the second outlet hole being located near another edge opposite from the second inlet hole in the longitudinal direction,   wherein the each plate and an adjacent plate define therebetween either one of a first flow path and a second flow path, the first flow path passing the first fluid entered from the first inlet hole to the first outlet hole such that the first fluid spreads in a lateral direction, and the second flow path passing the second fluid entered from the second inlet hole to the second outlet hole such that the second fluid spreads in the lateral direction, and the each plate exchanges heat between the first fluid flowing through the first flow path and the second fluid flowing through the second flow path, and   wherein the each plate is configured such that a length in the longitudinal direction is 4 or more times a length in the lateral direction.   
     
     
         2 . The plate heat exchanger according to  claim 1 ,
 wherein each of a length from the first inlet hole to a plate edge proximate to the first inlet hole in the lateral direction, a length from the first outlet hole to a plate edge proximate to the first outlet hole in the lateral direction, a length from the second inlet hole to a plate edge proximate to the second inlet hole in the lateral direction, and a length from the second outlet hole to a plate edge proximate to the second outlet hole in the lateral direction is not more than 6 percent of the length in the lateral direction.   
     
     
         3 . The plate heat exchanger according to  claim 1 ,
 wherein each of a length from the first inlet hole to a plate edge proximate to the first inlet hole in the lateral direction, a length from the first outlet hole to a plate edge proximate to the first outlet hole in the lateral direction, a length from the second inlet hole to a plate edge proximate to the second inlet hole in the lateral direction, and a length from the second outlet hole to a plate edge proximate to the second outlet hole in the lateral direction is not more than 5.6 mm.   
     
     
         4 . The plate heat exchanger according to  claim 1 ,
 wherein each of an opening area of the first inlet hole and an opening area of the first outlet hole is smaller than either of an opening area of the second inlet hole and an opening area of the second outlet hole.   
     
     
         5 . The plate heat exchanger according to  claim 4 ,
 wherein a center of the first inlet hole and a center of the first outlet hole are positioned nearer to a plate edge relative to a center of the second inlet hole and a center of the second outlet hole.   
     
     
         6 . The plate heat exchanger according to  claim 4 ,
 wherein a first plate and a second plate are stacked alternately,   wherein the first inlet hole and the second outlet hole are positioned near a same edge in the longitudinal direction, and   wherein the first plate includes a sealing portion for preventing a fluid entered from the first inlet hole from flowing to the second outlet hole, the sealing portion being formed as a protrusion raised in a stacking direction of the plurality of stacked plates such that the sealing portion extends from near the edge where the first inlet hole and the second outlet hole are located toward an opposite edge in the longitudinal direction, so as to gradually approach an edge in the lateral direction near the second outlet hole.   
     
     
         7 . The plate heat exchanger according to  claim 4 ,
 wherein the each plate includes V-shaped convex portions and concave portions arranged in a plurality of arrays in the longitudinal direction, each of the convex portions and concave portions having ends at both ends in the lateral direction and also having a turning point longitudinally misaligned with the ends, so that the convex portions and concave portions are formed in a V shape, and   wherein, in a vicinity of at least either hole of the first inlet hole and the first outlet hole, the V-shaped convex portions and concave portions are formed such that a position of the turning point is gradually shifted toward the either hole away from a center in the lateral direction as a position of each of the V-shaped convex portions and concave portions becomes nearer to the each hole.   
     
     
         8 . The plate heat exchanger according to  claim 4 ,
 wherein the plurality of stacked plates are stacked such that the first inlet hole of the each plate is aligned with first inlet holes of other plates, so that the first fluid sequentially flows from the first inlet hole of the each plate stacked at one side of the stacking direction into the first inlet hole of the each plate stacked at another side of the stacking direction, and   wherein the nearer the each plate of the plurality of stacked plates is to the one side from which the first fluid enters, the smaller a diameter of the first inlet hole.   
     
     
         9 . The plate heat exchanger according to  claim 1 ,
 wherein the first inlet hole and the second outlet hole are formed near a same edge in the longitudinal direction, and the second inlet hole and the first outlet hole are formed near a same edge in the longitudinal direction, and   wherein a shape of the first inlet hole is different from a shape of the second outlet hole, and a shape of the second inlet hole is different from a shape of the first outlet hole.   
     
     
         10 . The plate heat exchanger according to  claim 9 ,
 wherein the first inlet hole and the second outlet hole are formed by dividing one hole of a circular, elliptical, or polygonal shape into two holes, and   wherein the second inlet hole and the first outlet hole are formed by dividing one hole of a circular, elliptical, or polygonal shape into two holes.   
     
     
         11 . A refrigeration air conditioner comprising the plate heat exchanger according to  claim 1 . 
     
     
         12 . A plate heat exchanger configured with a plurality of stacked plates,
 wherein each plate of the plurality of stacked plates includes:   a first inlet hole which acts as an inlet for a first fluid, the first inlet hole being located near one edge in the longitudinal direction;   a first outlet hole which acts as an outlet for the first fluid, the first outlet hole being located near another edge opposite from the first inlet hole in the longitudinal direction;   a second inlet hole which acts as an inlet for a second fluid, the second inlet hole being located near one edge in the longitudinal direction; and   a second outlet hole which acts as an outlet for the second fluid, the second outlet hole being located near another edge opposite from the second inlet hole in the longitudinal direction,   wherein the each plate and an adjacent plate define therebetween either one of a first flow path and a second flow path, the first flow path passing the first fluid entered from the first inlet hole to the first outlet hole such that the first fluid spreads in a lateral direction, and the second flow path passing the second fluid entered from the second inlet hole to the second outlet hole such that the second fluid spreads in the lateral direction, and the each plate exchanges heat between the first fluid flowing through the first flow path and the second fluid flowing through the second flow path, and   wherein each of a length from the first inlet hole to a plate edge proximate to the first inlet hole in the lateral direction, a length from the first outlet hole to a plate edge proximate to the first outlet hole in the lateral direction, a length from the second inlet hole to a plate edge proximate to the second inlet hole in the lateral direction, and a length from the second outlet hole to a plate edge proximate to the second outlet hole in the lateral direction is not more than 6 percent of a length in the lateral direction.   
     
     
         13 . A plate heat exchanger configured with a plurality of stacked plates,
 wherein each plate of the plurality of stacked plates includes:   a first inlet hole which acts as an inlet for a first fluid, the first inlet hole being located near one edge in the longitudinal direction;   a first outlet hole which acts as an outlet for the first fluid, the first outlet hole being located near another edge opposite from the first inlet hole in the longitudinal direction;   a second inlet hole which acts as an inlet for a second fluid, the second inlet hole being located near one edge in the longitudinal direction; and   a second outlet hole which acts as an outlet for the second fluid, the second outlet hole being located near another edge opposite from the second inlet hole in the longitudinal direction,   wherein the each plate and an adjacent plate define therebetween either one of a first flow path and a second flow path, the first flow path passing the first fluid entered from the first inlet hole to the first outlet hole such that the first fluid spreads in a lateral direction, and the second flow path passing the second fluid entered from the second inlet hole to the second outlet hole such that the second fluid spreads in the lateral direction, and the each plate exchanges heat between the first fluid flowing through the first flow path and the second fluid flowing through the second flow path, and   wherein each of a length from the first inlet hole to a plate edge proximate to the first inlet hole in the lateral direction, a length from the first outlet hole to a plate edge proximate to the first outlet hole in the lateral direction, a length from the second inlet hole to a plate edge proximate to the second inlet hole in the lateral direction, and a length from the second outlet hole to a plate edge proximate to the second outlet hole in the lateral direction is not more than 5.6 mm.