An engine cooling system including a refrigerant circulation flow channel passing through an engine, an electric refrigerant pump, an electromagnetic valve arranged in the refrigerant circulation flow channel, and a control unit. In the engine cooling system, when the electric refrigerant pump is stopped and the voltage application to the electromagnetic valve is shut off when the electromagnetic valve is closed and the electric refrigerant pump is in operation, the voltage application to the electromagnetic valve is shut off when a first predetermined time period has passed after the electric refrigerant pump is stopped. When the engine is intermittently stopped during warming up of the engine, current application to the electromagnetic valve is shut off while the closed state of the electromagnetic valve is maintained.

A cooling system for an engine is provided. The cooling system includes coolant flow paths including a first flow path and a second flow path and where coolant circulates, a coolant pump for circulating the coolant within the coolant flow paths, a flow rate control valve for adjusting a flow rate of the coolant through the second flow path, a temperature detector for detecting a temperature of the coolant within the first flow path, a valve controller for adjusting an opening of the flow rate control valve based on the temperature detected by the temperature detector, and an output level determiner for determining an output level of the engine based on at least one of a fuel injection amount for the engine and an engine speed.

A work vehicle includes a drive unit, a fan motor, a fan configured to be driven by the fan motor, an overrun state detecting unit configured to detect an overrun state of the drive unit, and a control unit. The control unit is configured to control a rotational speed of the fan to reach a first fan rotational speed by increasing the rotational speed of the fan when a detection value detected by the overrun state detecting unit becomes greater than or equal to a first threshold. The control unit is configured to control the rotational speed of the fan to reach a second fan rotational speed higher than the first fan rotational speed when the detection value becomes greater than or equal to a second threshold greater than the first threshold.

A cooling system for an air-cooled engine includes a plurality of electric fans, a plurality of ducts, each duct configured to receive one of the plurality of electric fans, a housing, the housing configured to be coupled to the engine and to include at least one opening, each opening is configured to be coupled to receive one of the plurality of ducts to direct air from the electric fans to a plurality of target locations, a sensor, the sensor is configured to acquire sensor data regarding the operation of the engine, and a processing circuit, the processing circuit is configured to receive the sensor data from the sensor and to control operation of the plurality of electric fans in accordance with the sensor data.

A coolant circuit has an engine cooling circuit in which coolant can be circulated in order to cool an internal combustion engine via a cylinder head cooling circuit and a crankcase cooling circuit separated from the cylinder head cooling circuit. The coolant circuit includes a transmission cooling circuit for cooling a transmission, the transmission cooling circuit branching off from the engine cooling circuit. A valve is arranged in the transmission cooling circuit. A controller is designed to open and close the valve depending on an operating state of the internal combustion engine and/or the transmission. In particular, the transmission cooling circuit branches off from the crankcase cooling circuit to a section along which the crankcase cooling circuit is separated from the cylinder head cooling circuit.

A thermal management and control method includes: determining a total target amount of to-be-dissipated heat of an engine based on a minimum engine fuel consumption lookup table when a current temperature of the engine is greater than or equal to a temperature threshold and an opening degree of the thermostat is greater than or equal to an opening degree threshold; querying a minimum thermal management system power consumption lookup table based on the total target amount of to-be-dissipated heat, an air inlet speed of an air-cooling radiator, and a current ambient temperature, and determining a target rotation speed of a water pump and a target rotation speed of the air-cooling radiator; and controlling a rotation speed of the water pump to be the target rotation speed of the water pump, and controlling a rotation speed of the air-cooling radiator to be the target rotation speed of the air-cooling radiator.

A control system for a cooling fan that can ensure cooling capability of the cooling fan is provided. The control system includes an engine, a work implement driven by the engine, a cooling fan configured such that the number of rotations thereof is controllable independently of the number of rotations of the engine, and a controller that controls the cooling fan. The controller controls the cooling fan to make a difference in frequency between the cooling fan and the engine larger than the difference at a time point when the controller obtains the frequency of the cooling fan, by changing the frequency of the cooling fan when the number of rotations of the engine is larger than a threshold value and the frequency of the cooling fan is within a prescribed range from a frequency of the engine while the work implement is in a standstill.

A method is disclosed for improving fuel economy in an internal combustion engine. The method may involve sensing a temperature of an engine block and determining a block thermal energy representing an ability of the block to reject heat. An open loop control scheme may be used together with the block thermal energy to predict if a coolant in the block is about to enter a boiling condition and, when this is about to occur, to open a block valve to permit a flow of coolant through the block. A closed loop control scheme may be used together with the sensed temperature of the block to determine if a coolant boiling condition is about to occur, and to control the block valve to permit a flow of coolant through the block which is just sufficient to prevent the onset of coolant boiling in the block.

A coolant control system of a vehicle includes a coolant valve control module and a pump control module. The coolant valve control module determines a position of a coolant valve. The pump control module determines a speed of a coolant pump based on the position of the coolant valve and a desired coolant output temperature, measures a coolant output temperature, determines a difference between the desired coolant output temperature and the measured coolant output temperature, generates a correction factor based on the difference between the desired coolant output temperature and the measured coolant output temperature, and applies the correction factor to the speed of the coolant pump.

A cooling system for an air-cooled engine includes a plurality of electric fans, a plurality of ducts, each duct configured to receive one of the plurality of electric fans, a housing, the housing configured to be coupled to the engine and to include at least one opening, each opening is configured to be coupled to receive one of the plurality of ducts to direct air from the electric fans to a plurality of target locations, a sensor, the sensor is configured to acquire sensor data regarding the operation of the engine, and a processing circuit, the processing circuit is configured to receive the sensor data from the sensor and to control operation of the plurality of electric fans in accordance with the sensor data.