Plate heat exchanger and heat pump hot water supply system

Abstract

A plate heat exchanger has first heat transfer plates and second heat transfer plates laminated atop one another, and each including a plate portion in which an inflow/outflow hole is formed, a first outer circumferential wall portion or second outer circumferential wall portion that extends on one surface side of the plate portion and that defines a channel together with a plate portion adjacent to the one surface side, and a first inner fin or a second inner fin that is attached to an inside portion of the channel. The first inner fin is mounted at a position, spaced part from a first fluid inflow/outflow hole, inside the channel, on the one surface of the plate portion and the second inner fin is mounted at a position, spaced apart from a second fluid inflow/outflow hole inside the channel, on the one surface of the plate portion.

1 - 11 . (canceled) 
     
     
         12 . A plate heat exchanger comprising:
 first heat transfer plates and second heat transfer plates that are laminated alternatingly atop one another,   wherein   the first heat transfer plates each include:
 a first plate portion in which a first inflow/outflow hole is formed that causes a first fluid to flow in and out, 
 a first outer circumferential wall portion that surrounds an outer circumference of the first plate portion on one surface side of the first plate portion, the first outer circumferential wall portion defining a first channel for allowing the first fluid to flow, and 
 a first inner fin that is mounted at a position, spaced apart from the first inflow/outflow hole inside the first channel, on the one surface of the first plate portion, 
   the second heat transfer plates each include:
 a second plate portion in which a second inflow/outflow hole is formed that causes a second fluid to flow in and out, 
 a second outer circumferential wall portion that surrounds an outer circumference of the second plate portion on one surface side of the second plate portion, the second outer circumferential wall portion defining a second channel for allowing the second fluid to flow, and 
 a second inner fin that is mounted at a position, spaced apart from the second inflow/outflow hole inside the second channel, on the one surface of the second plate portion, and 
   the second plate portion includes:
 a first convexity placed between the second inflow/outflow hole and the second inner fin in the second channel, the first convexity protruding toward one surface side of the second plate portion and abutting against a first plate portion that is included in a first heat transfer plate adjacent to the one surface side, and 
 a second convexity placed between the first inflow/outflow hole and the first inner fin in the first channel, the second convexity protruding toward another surface side of the second plate portion and abutting against a first plate portion that is included in a first heat transfer plate adjacent to the another surface side. 
   
     
     
         13 . The plate heat exchanger according to  claim 12 , wherein the first convexity and the second convexity are arranged on the second plate portion at positions offset from each other as viewed in a direction of the lamination of the first heat transfer plates and the second heat transfer plates atop one another. 
     
     
         14 . The plate heat exchanger according to  claim 12 , wherein
 the second plate portion includes a plurality of the first convexities and a plurality of the second convexities, and   on the second plate portion, the first convexities are provided in greater number than that of the second convexities when the second fluid with a pressure higher than that of the first fluid flows through the second channel and the second convexities are provided in greater number than that of the first convexities when the first fluid with a pressure higher than that of the second fluid flows through the first channel.   
     
     
         15 . The plate heat exchanger according to  claim 12 , wherein
 the first plate portion that is included in each first heat transfer plate is a flat plate, and   the first convexity and the second convexity abut against a plate surface of the first plate portion.   
     
     
         16 . The plate heat exchanger according to  claim 12 , wherein the first plate portion includes:
 a third convexity that protrudes toward one surface side of the first plate portion and abuts against a second convexity of a second plate portion that is included in a second heat transfer plate adjacent to the one surface side, thereby maintaining a shape of the first channel in a direction of the lamination of the first heat transfer plates and the second heat transfer plates atop one another, and   a fourth convexity that protrudes toward another surface side of the first plate portion and abuts against a first convexity of a first plate portion that is included in a first heat transfer plate adjacent to the another side surface, thereby maintaining a shape of the second channel in the direction of the lamination of the first heat transfer plates and the second heat transfer plates atop one another.   
     
     
         17 . The plate heat exchanger according to  claim 12 , wherein
 an entire periphery of the first inflow/outflow hole is in contact with a first space where the first inner fin is not provided and an entire periphery of the second inflow/outflow hole is in contact with a second space where the second inner fin is not provided, and   the second convexity is placed in the first space and the first convexity is placed in the second space.   
     
     
         18 . The plate heat exchanger according to  claim 17 , wherein
 the first plate portion and the second plate portion are rectangular in shape as viewed in plan view,   the first inner fin and the second inner fin are rectangular in shape as viewed in the plan view and are shorter in length than the first plate portion and the second plate portion in a longitudinal direction, and   sides of the first inner fin in a transverse direction are spaced apart from the first inflow/outflow hole and sides of the second inner fin in the transverse direction are spaced apart from the second inflow/outflow hole.   
     
     
         19 . The plate heat exchanger according to  claim 12 , wherein
 the first plate portion includes (i) a first passage hole surrounded by a first tubular wall, the first passage hole causing the second fluid to flow into or flow from the second channel formed on the second plate portion and (ii) a first flange that is provided on an end of the first tubular wall and is to be joined to the second heat transfer plate, and   the second plate portion includes (i) a second passage hole surrounded by a second tubular wall, the second passage hole causing the first fluid to flow into or flow from the first channel formed on the first plate portion and (ii) a second flange that is provided on an end of the second tubular wall and is to be joined to the first heat transfer plate.   
     
     
         20 . The plate heat exchanger according to  claim 12 , wherein
 a distance at which the first inner fin is spaced apart from the first inflow/outflow hole is greater than a pitch between fin sections included in the first inner fin, and   a distance at which the second inner fin is spaced apart from the second inflow/outflow hole is greater than a pitch between fin sections included in the second inner fin.   
     
     
         21 . A heat pump hot water supply system comprising:
 the plate heat exchanger according to  claim 12 ,   wherein the plate heat exchanger performs heat exchange between refrigerant and water.