Coolant circuit for a coolant-cooled internal combustion engine
In a coolant circuit for an internal combustion engine having two cylinder banks, a radiator for cooling the engine coolant, a pump and a thermostatic valve including a mixing chamber and first and second flow control valves, wherein the pump is connected to the radiator via an intake line for receiving coolant therefrom and supplying it to the cylinder banks which are in communication with the mixing chamber from which a radiator line extends to the radiator for returning heated coolant to the radiator under the control of a flow control valve, or supplying it via a bypass line to the intake line under the control of a bypass valve, a heating circuit is provided extending from one of the cylinder banks via a heater to the pump intake line and a heater control valve is disposed in the heating control circuit so that, upon opening of the heater valve, coolant flows from the other cylinder bank via the mixing chamber to the one cylinder bank and coolant from both cylinder banks jointly flows through the heating circuit back to the pump.
1. A coolant circuit ( 37 ) for an internal combustion engine ( 38 ) having two cylinder banks ( 39 , 40 ), a radiator ( 52 ) for cooling a coolant, a pump ( 41 ) for pumping the coolant and a thermostatic valve ( 5 ″) including a mixing chamber ( 47 ) and first and second flow control valves ( 50 , 51 ), said pump being connected to the radiator ( 32 ) via an intake line ( 42 ) for receiving coolant therefrom and pumping it to the cylinder banks ( 39 , 40 ) via line strands ( 43 , 44 ), said cylinder banks ( 39 , 40 ) being in communication with the mixing chamber ( 47 ) via discharge lines ( 45 , 46 ), a radiator line ( 48 ) extending from the mixing chamber ( 47 ) to the radiator ( 52 ) for returning coolant to the radiator under the control of a main flow control valve ( 50 ), a bypass line ( 49 ) extending from the mixing chamber ( 47 ) to the intake line ( 42 ) for bypassing the radiator ( 52 ) during engine warm-up under the control of a by-pass flow control valve ( 51 ), and a heating circuit ( 53 , 54 ) including a heater ( 55 ) and extending from one of the cylinder banks ( 39 , 40 ) to the pump intake line ( 42 ), said heating circuit ( 53 , 54 ) including a heater control valve ( 57 ) for controlling the flow of coolant from said one of the cylinder banks ( 39 , 40 ) to said pump supply line ( 42 ) so that, upon opening of the heater flow control valve ( 57 ), heated coolant flows not only from said one of the cylinder banks ( 39 , 40 ) but also from the other of said cylinder banks ( 39 , 40 )) via the discharge lines ( 45 , 46 ) and the mixing chamber ( 47 ) and also the one of the cylinder banks ( 39 , 40 ) through said heater ( 55 ) to said pump ( 41 ).
2. A coolant circuit for an internal combustion engine as claimed in claim 1 , wherein, when the internal combustion engine ( 38 ) is operationally hot, the coolant flow through the heating circuit ( 53 , 54 ) can be controlled or even blocked by the heating valve ( 57 ).