An electronic thermostat, into which cooling water is flowed from a cylinder head of an engine through a first inlet, controls the flow rate of the received cooling water supplied to outside ambient air exposure. The electronic thermostat includes a first valve for controlling the flow rate of the cooling water supplied to a first passage for connecting a first outlet of the electronic thermostat and a water pump and includes a second valve for controlling the flow rate of the cooling water flowing through a second passage for connecting the outlet of a radiator and a cylinder block of the engine.

A coolant control system includes: a high temperature radiator communicating with an engine through a high temperature coolant line, a high temperature coolant pump, a coolant temperature sensor, a low temperature radiator, a low temperature coolant pump, a water-cooled intercooler, an intake air temperature sensor, bypass valves provided upstream and downstream of the water-cooled intercooler for selectively controlling the high temperature coolant or the low temperature coolant to flow through the water-cooled intercooler, an ambient temperature sensor, a radiator bypass line connected to the high temperature coolant line and bypassing the high temperature radiator, a thermostat to selectively flow the high temperature coolant to the radiator bypass line, and a controller for controlling the operations of the low temperature coolant pump, the bypass valve and the thermostat in accordance with a vehicle operation state.

Disclosed is a cooler arrangement for cooling a cylinder of a combustion engine. The cylinder has a cylinder head and a cylinder liner. The arrangement comprises a cooling circuit with a first flow passage which leads coolant through a lower part of the cylinder head, a second flow passage which leads coolant through an upper part of the cylinder head, and a third flow passage which leads coolant through an upper part of the cylinder liner. The cooling circuit is adapted to initially leading coolant through the first flow passage before it is led in parallel through the second flow passage and the third flow passage.

A coolant control valve unit includes a valve housing. The valve housing includes a first coolant supply passage and a second coolant supply passage, a coolant chamber in which coolant supplied through the first and second supply passages gathers, a first distribution passage and a second distribution passage being distributed from the coolant chamber to coolant components, and a bypass passage bypassing the first distribution passage. The coolant control valve unit also includes first and second valves disposed to open and close the first distribution passage and the second supply passage, a thermostat of a temperature sensitive type installed at the bypass and operating by a coolant temperature, a valve operator controlling movement of the first and second valves, respectively, and a wall formed at one side of the thermostat and in which a cooling passage is formed such that the coolant flows from the coolant supply passage to the second distribution passage.

A coolant control valve unit for a vehicle engine is disclosed. The coolant control valve unit includes a rod at one side of which a valve opening and closing a coolant passage, a cap at which a rod groove into which one end of the rod is inserted is provided, a cap elastic member inserted inside the rod groove to elastically support one end of the rod outwardly, a cam with one surface of which a driving axle is connected and at the other surface of which at least one of pressing surface is provided in a rotational direction with respect to a rotational center portion, and a valve elastic member elastically supporting the valve to one side so that the cap contacts with the pressing surface.

At cold start of an internal combustion engine having an EGR system configured to recirculate, to an intake system, a portion of exhaust gas from the internal combustion engine, supply of a coolant to an EGR cooler and an air conditioning heater which are provided in a coolant circuit for circulating the coolant through the internal combustion engine and an outside thereof is shut off, when a temperature of the coolant is less than a predetermined temperature, and supply of the coolant to the air conditioning heater is allowed and supply of the coolant to the EGR cooler is shut off until the EGR system is activated, when the temperature of the coolant is equal to or higher than the predetermined temperature.

In an engine, a cylinder block and a cylinder head are connected with a crankcase in a forwardly inclined posture. A dual clutch connects or disconnects a transmission path of power of the engine to a transmission. An actuator chamber houses an actuator that controls a hydraulic pressure of the dual clutch. The actuator chamber is disposed on an upper surface of the cylinder block at a position posterior to the cylinder head and anterior to the crankcase in a vehicle longitudinal direction.

The present disclosure relates to a separate cooling system of a vehicle, including an engine including a cylinder head and a cylinder block transmitting a coolant to the cylinder head, a coolant pump, a plurality of parts disposed on a plurality of coolant lines, an electronic thermostat mounted on the cylinder block so as to selectively transmit the coolant from the cylinder block to the plurality of coolant lines, a cooling coolant temperature sensor measuring a coolant temperature of the cylinder block, a controller controlling an operation of the electronic thermostat depending on a vehicle operation state output signal including the cooling coolant temperature sensor, and a mechanical thermostat disposed at an upstream of the coolant pump so as to selectively block the coolant via a radiator and a reservoir tank among the coolant transmitted from the plurality of coolant line to the coolant pump.

An engine cooling system may include a first water jacket provided in a cylinder block; a second water jacket provided in a cylinder head; a main line connected to a water pump, the first water jacket, the second water jacket, and a radiator such that a coolant discharged from the water pump passes through the first water jacket and the second water jacket to be circulated to the water pump via the radiator; the third water jacket provided in a cylinder separately from the first water jacket or the second water jacket; and a sub-line connected to the water pump and the third water jacket such that the coolant discharged from the water pump passes through the third water jacket to be directly circulated to the water pump without passing through the radiator.

The invention of the present application relates to a control device and a control method for a cooling device. A cooling device includes a first cooling water passage of a cylinder head, a second cooling water passage of a cylinder block, a control valve that changes a ratio between a flow rate of the first cooling water passage and a flow rate of the second cooling water passage, and a water pump. Then, the control device controls the control valve so that a ratio of the flow rate of the first cooling water passage increases when a cooling water circulation flow rate is insufficient due to failure of the water pump. Accordingly, it is possible to suppress damage of an engine body while suppressing deterioration in traveling performance of a vehicle when failure occurs in the water pump.