Method for improving the cold start capacity of an internal combustion engine, and crankcase ventilating device for this purpose
A method for improving the cold start capacity of an internal combustion engine which is cooled with water that is pre-heated for the cold start. The pre-heated hot water is conducted through flow paths in a region of the crankcase ventilating device and/or in a water/air heat exchanger of the crankcase ventilating device. An internal combustion engine with at least one cooling water circuit, at least one cooling water pump which is arranged in the cooling water circuit, and at least one crankcase ventilating device. The crankcase ventilating device is at least temporarily integrated into the cooling water circuit of the internal combustion engine, and the cooling water circuit has a pre-heating assembly for pre-heating the cooling water when the internal combustion engine is cold started.
1. A method for improving cold-start characteristics of a water-cooled internal combustion engine, in which engine cooling water is pre-warmed for cold starting, the method comprising conducting the pre-warmed warm water through at least one flow path in a housing of a crankcase ventilation device and/or through a U-shaped water/air heat exchanger provided in the housing so that legs of the U-shape are closely against a clean-air manifold.
2. The method according to claim 1 , including extracting the warm water from a pre-warming unit of the internal combustion engine.
3. The method according to claim 2 , wherein the pre-warming unit is incorporated in a cooling water circuit, the water of the cooling water circuit being pre-heated during the cold start.
4. The method according to claim 1 , wherein the pre-warming branch is connected as a bypass line with respect to a flow path of the cooling water circuit.
5. The method according to claim 1 , including conducting the warm water through the water/air heat exchanger in an oil separation region and/or a filter region of the housing of the crankcase ventilation device.
6. The method according to claim 1 , including stopping the warm water supply to the crankcase ventilation device when a defined temperature is reached.
7. The method according to claim 6 , including stopping the warm water supply by conducting the warm water past the crankcase ventilation device.
8. An internal combustion engine, comprising: at least one cooling water circuit; at least one cooling water pump arranged in the cooling water circuit; at least one crankcase ventilation device, wherein the crankcase ventilation device is at least temporarily incorporated into the cooling water circuit, wherein the cooling water circuit includes a pre-warming unit for preheating the cooling water during a cold start of the internal combustion engine, the pre-warming unit including a U-shaped water/air heat exchanger provided so that legs of the U-shape are closely against a clean-air manifold.
9. The internal combustion engine according to claim 8 , wherein at least one flow path for the cooling water is provided in a wall of the crankcase ventilation device.
10. The internal combustion engine according to claim 8 , wherein the water/air heat exchanger is arranged in the crankcase ventilation device, the water/air heat exchanger having cooling water ducts as flow paths for the cooling water.
11. The internal combustion engine according to claim 8 , wherein, in parallel with respect to a flow path of the cooling water, a bypass is provided to the pre-warming unit for the crankcase ventilation device, the bypass being openable when a defined cooling water temperature is exceeded.
12. The internal combustion engine according to claim 11 , wherein a temperature-controlled valve is arranged in the bypass.
13. The internal combustion engine according to claim 12 , wherein the temperature-controlled valve includes a bimetal actuator.
14. The internal combustion engine according to claim 8 , further comprising an engine block having a cooling water outlet opening and a cooling water inlet opening, to which a feed line and a return line of the pre-warming device of the crankcase ventilation device are connected.
15. The internal combustion engine according to claim 14 , wherein the cooling water outlet opening and/or the cooling water inlet opening for the feed line and/or the return line of the pre-warming device of the crankcase ventilation device are connected to a cooling water permanent ventilation and/or to a water-conducting housing of the engine block.
16. A crankcase ventilation device for an internal combustion engine according to claim 8 , the crankcase ventilation device comprising has at least one warm-water inlet and one warm-water outlet and at least one interposed flow path for warm water, wherein the at least one flow path is a primary side of the water/air heat exchanger.
17. The crankcase ventilation device according to claim 16 , wherein the water/air heat exchanger is arranged in or at an oil separation region of a housing of the crankcase ventilation device.
18. The crankcase ventilation device according to claim 16 , wherein at least one valve is arranged in the flow path, the valve being closed by a temperature-actuated actuator when a threshold temperature is exceeded.