Patent ID: 7704221

Claim:
A rotary valve unit for blending hot and cold fluid sources to regulate a temperature of fluid flowing to a heat exchange unit in an extracorporeal blood perfusion circuit comprising: a valve body comprising: a valve chamber including a first inlet port, a second inlet port, a first outlet port, and a second outlet port; a first fluid channel in fluid communication with the first inlet port, the first fluid channel receiving a cold fluid from a cold storage tank; a second fluid channel in communication with the first outlet port, the first outlet port returning fluids received from at least one of the inlets ports to the heat exchange unit; a third fluid channel in fluid communication with the second inlet port, the third fluid channel receiving a returned fluid from the heat exchange unit; a fourth fluid channel in communication with the second outlet port, the fourth fluid channel returning fluids received from the second inlet port to the cold storage tank; and a wedge-shaped rotary valve disposed within the valve chamber, the rotary valve being rotatable within the valve chamber for controlling a blending of the cold fluid entering the valve chamber from the first inlet port and the return fluid from the heat exchange unit entering the valve chamber from the second inlet port to regulate the desired temperature of fluid provided to the heat exchange unit, the wedge-shaped rotary valve being positionable to provide either only the cold fluid to the first outlet port, only the return fluid to the first outlet port, or a blending of the cold fluid and return fluid to the first outlet port.