Patent ID: 6325026
Filing Date: 2001-12-04
Classification: F01P

Abstract:
A cooling water recirculation apparatus for an internal combustion engine, comprising:an internal combustion engine body having a cooling water internal passage for cooling a portion around a cylinder;a radiator for irradiating heat of said internal combustion engine body, absorbed by the cooling water, to atmosphere;a passenger room heater using a part of the cooling water as a heat medium;a radiator side cooling water recirculation circuit for recirculating the cooling water between said cooling water internal passage of said internal combustion engine body and said radiator;a heater side cooling water recirculation circuit for recirculating the cooling water between said cooling water internal passage of said internal combustion engine body and said heater;a radiator bypass circuit for returning the cooling water, that has been discharged from said cooling water internal passage of said internal combustion engine body, back to said cooling water internal passage, bypassing said radiator;a cooling water passage switching means for closing said bypass circuit when a temperature of the cooling water exceeds a radiator water passage allowance temperature, thereby allowing the cooling water to flow through said radiator side cooling water recirculation circuit, and for closing said radiator side cooling water recirculation circuit when the temperature of the cooling water is not higher than the radiator water passage allowance temperature, thereby allowing the cooling water to flow through said radiator bypass circuit;an auxiliary heating means for heating the cooling water, provided separately from said internal combustion engine body and not located in the heater side cooling water recirculation circuit; anda flow rate control valve provided downstream of said cooling water internal passage of said internal combustion engine body and upstream of said passenger room heater in said heater side cooling water recirculation circuit, for reducing an amount of the cooling water flowing through said heater side cooling water recirculation circuit when the temperature of the cooling water is not higher than a heater water passage limit temperature that is set to be not higher than the radiator water passage allowance temperature;wherein said auxiliary heating means is provided in a portion of one of the cooling water internal passage and the radiator bypass circuit where cooling water heated by said auxiliary heating means flows into said heater side cooling water recirculation circuit without first being recirculated through said cooling water internal passage.