Thermostat monitor
First Claim
1. A thermostat monitor for detecting an open failure of a thermostat in an engine cooling water channel system, based on a temperature of an engine cooling water detected by a temperature sensor, the engine cooling water channel system having an engine, a heater core and a radiator of a vehicle positioned thereon, the engine cooling water channel system comprising an in-engine cooling water channel, a radiator-side cooling water channel and a heater core-side cooling water channel, the thermostat positioned on the radiator-side cooling water channel, and the temperature sensor positioned in the engine cooling water channel system between an outlet side of the engine and an inlet side of the heater core,wherein the thermostat monitor comprises a thermostat open failure detector that detects an occurrence of the open failure of the thermostat when:
- a radiator heat radiation amount radiated from the radiator on the radiator-side cooling water channel is larger than a heater core heat radiation amount radiated from the heater core on the heater core-side cooling water channel, anda difference between the radiator heat radiation amount and the heater core heat radiation amount is equal to or more than a predetermined value, andthe thermostat open failure detector refrains from detecting for the occurrence of the open failure of the thermostat when a vehicle speed of the vehicle is smaller than a predetermined speed.
1 Assignment
0 Petitions
Accused Products
Abstract
Provided is a thermostat monitor (36) comprising a thermostat open failure detecting part (38) for detecting an open failure of a thermostat when a condition is such that a radiator heat radiation amount (14) radiated from a radiator on a radiator-side cooling water channel is larger than a heater core heat radiation amount (12) radiated from a heater core on a heater core-side cooling water channel, and that a difference between the radiator heat radiation amount and the heater core heat radiation amount is equal to or more than a predetermined value A. Based on a temperature of engine cooling water detected by a temperature sensor positioned in the vicinity of an outlet of an in-engine cooling water channel, it is possible to detect the open failure of the thermostat relatively easily with certainty.
8 Citations
6 Claims
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1. A thermostat monitor for detecting an open failure of a thermostat in an engine cooling water channel system, based on a temperature of an engine cooling water detected by a temperature sensor, the engine cooling water channel system having an engine, a heater core and a radiator of a vehicle positioned thereon, the engine cooling water channel system comprising an in-engine cooling water channel, a radiator-side cooling water channel and a heater core-side cooling water channel, the thermostat positioned on the radiator-side cooling water channel, and the temperature sensor positioned in the engine cooling water channel system between an outlet side of the engine and an inlet side of the heater core,
wherein the thermostat monitor comprises a thermostat open failure detector that detects an occurrence of the open failure of the thermostat when: -
a radiator heat radiation amount radiated from the radiator on the radiator-side cooling water channel is larger than a heater core heat radiation amount radiated from the heater core on the heater core-side cooling water channel, and a difference between the radiator heat radiation amount and the heater core heat radiation amount is equal to or more than a predetermined value, and the thermostat open failure detector refrains from detecting for the occurrence of the open failure of the thermostat when a vehicle speed of the vehicle is smaller than a predetermined speed. - View Dependent Claims (2)
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3. A thermostat monitor for detecting an open failure of a thermostat in an engine cooling water channel system, based on a temperature of an engine cooling water detected by a temperature sensor, the engine cooling water channel system having an engine, a heater core and a radiator of a vehicle positioned thereon, the engine cooling water channel system comprising an in-engine cooling water channel, a radiator-side cooling water channel and a heater core-side cooling water channel, the thermostat positioned on the radiator-side cooling water channel, and the temperature sensor positioned in the engine cooling water channel system between an outlet side of the engine and an inlet side of the heater core,
wherein the thermostat monitor comprises a temperature difference detector which causes the detection for the open failure of the thermostat to start when a condition is met such that a temperature difference between the temperature of the engine cooling water detected by the temperature sensor and external air temperature is equal to or more than a predetermined value, and the thermostat monitor refrains from detecting for the occurrence of the open failure of the thermostat when a vehicle speed of the vehicle is smaller than a predetermined speed.
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6. A thermostat monitor for detecting an open failure of a thermostat in an engine cooling water channel system, based on a temperature of an engine cooling water detected by a temperature sensor, the engine cooling water channel system having an engine, a heater core and a radiator of a vehicle positioned thereon, the engine cooling water channel system comprising an in-engine cooling water channel, a radiator-side cooling water channel and a heater core-side cooling water channel, the thermostat positioned on the radiator-side cooling water channel, and the temperature sensor positioned in the vicinity of an outlet of the in-engine cooling water channel,
wherein the thermostat monitor comprises a thermostat open failure detector that detects an occurrence of the open failure of the thermostat when: -
a radiator heat radiation amount radiated from the radiator on the radiator-side cooling water channel is larger than a heater core heat radiation amount radiated from the heater core on the heater core-side cooling water channel, and a difference between the radiator heat radiation amount and the heater core heat radiation amount is equal to or more than a predetermined value, and the thermostat open failure detector refrains from detecting for the occurrence of the open failure of the thermostat when a vehicle speed of the vehicle is smaller than a predetermined speed.
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Specification