DE102019001025B4 - Internal combustion engine with an open crankcase ventilation - Google Patents

Abstract

Supercharged internal combustion engine (8) with an open crankcase ventilation, comprising at least one crankcase (1), at least one crankcase ventilation (2), at least one collecting container (4) and at least one oil return device (7), and wherein the collecting container (4) has a cover (5) has, which protrudes over the edge of the collecting container (4).

Description

The invention relates to an internal combustion engine with an open crankcase ventilation.

Oil separators in internal combustion engines have the task of cleaning the oil-gas mixture in the crankcase by separating the oil droplets from this mixture and returning them to the oil sump of the oil pan, while the gases are fed into the intake area. For this purpose, the oil separator is connected to the crankcase at its inlet and to the intake area at its outlet. An oil separator of the type mentioned above is, for example, from DE 4239108 A1 known, for the return of the separated oil return lines are provided there, which open below the oil level in the oil sump of the oil pan. the DE 4017074 A1 discloses a pressure control valve for crankcase ventilation on an internal combustion engine, this pressure control valve being arranged in combination with a filling opening for engine oil and an oil dipstick. This combination is characterized by the fact that it saves space and centrally connects all components that affect the oil supply and monitoring of an internal combustion engine. This combination is also characterized by the fact that only a single connection is required on the engine block, through which the oil to be filled in or the oil flowing back from the pressure control valve is fed to the oil pan and also accommodates the oil dipstick.

the DE 11 2007 003 054 T5 shows an open crankcase ventilation system with an oil separator and recirculation.

the DE 10 2008 035 850 A1 shows an oil return valve for a crankcase ventilation of an internal combustion engine with oil drain openings in a housing that forms an oil collecting chamber.

the DE 10 2008 058 962 A1 shows a crankcase ventilation device of an internal combustion engine with an oil collection chamber which is connected to a siphon reservoir via a second oil return.

the DE 10 2013 212 104 A1 shows a crankcase ventilation of an internal combustion engine with an oil separator, an oil separator space and an oil collection space, each of which is delimited by a housing. An oil drain opening is provided in the housing, via which the separated oil is returned to an oil sump.

the DE 10 2017 120 139 A1 shows an oil mist separator for separating oil mist from the crankcase ventilation gas of an internal combustion engine with a housing having two oil returns.

Next is from the WO 98/49432A1 It is known to separate oil droplets from an oil droplet-gas mixture under the centrifugal effect of a gear wheel rotating in a housing, with a tube aligned with the axis of rotation of the gear wheel discharging the cleaned gases from the housing.

From the JP 2000-38915 A an oil separator arranged on a cylinder head cover is known, which has a housing on whose horizontal bottom surface three L-shaped angles are arranged, the rear sides of the vertical L-beams being aligned with drainage openings in the bottom surface. A pipe is pushed into the housing at the top of the housing, through which the gases, freed from oil droplets, escape via a valve.

the DE 2103061 A shows a device for recirculating gases from the engine housing of an internal combustion engine into its gas induction system.

From the DE 423791 A is an internal combustion engine with a device for ventilation of the crankcase, especially in motorcycles, known in which the contamination of the machine or the driver's clothing and oil losses are to be excluded. In turbocharged engines whose oil-containing gas is fed in front of the turbine, there is a risk in supercharged engines that the high temperatures in the turbine will result in varnish deposits that can be harmful to the turbocharger. For this reason, the possibility of using an open crankcase ventilation is used with this type of engine. The disadvantage here is that this collection container must be maintained. Here, the crankcase gases are discharged to the outside. As described above, these gases still contain oil despite pre-separation and oil can also escape, which is also disadvantageous.

DE 19914166 A1 shows a rotary oil separator for cleaning the gas contained in the crankcase of an internal combustion engine, in particular a self-igniting internal combustion engine.

Crankcase ventilation gas or also blow-by gas, referred to below as crankcase gas, is gas that gets past the piston rings and into the crankcase during engine operation. From this crankcase gas that must be taken mene oil are removed and the cleaned crankcase gas is then supplied in particular to the combustion air. Today, oil is separated from the crankcase gases mainly with the help of separators consisting of a knitted fabric of fibers, or with the help of jet deflections on baffle plates, or a combination of both processes. For future engines, the levels of separation that can be achieved with previous separators are not effective enough. Therefore, ultra-fine filters, possibly also as replaceable filter systems, are used. However, these have the disadvantage that, due to their nature, they work with a high differential pressure and thus lead to sealing problems on the motor.

The object of the invention is to create an internal combustion engine which avoids the disadvantages mentioned above.

The invention solves the problem set by an internal combustion engine with an open crankcase ventilation, comprising at least one crankcase, at least one crankcase ventilation, at least one collecting container and at least one oil return device and wherein the collecting container has a cover that protrudes over the edge of the collecting container.

To improve the oil return, it is also advantageous if the crankcase ventilation is arranged essentially in the area of the cylinder head.

In a preferred embodiment, the collection container and the crankcase ventilation can be connected by means of at least one ventilation pipe.

Further advantageous configurations can be found in the dependent claims.

A preferred exemplary embodiment of an arrangement according to the invention is explained in more detail below with reference to the attached drawing.

The only figure shows an internal combustion engine with an open crankcase ventilation.

An internal combustion engine generates pressures within the crankcase and in the components connected to it as a result of gases flowing past the piston rings.

These gases are usually fed back to the engine for combustion through a crankcase ventilation system equipped with valves, separating mats, separating bodies or similar, so that no oil-containing gases escape and no oil can settle.

In the case of turbo engines, in which the oil-containing gas is supplied upstream of the turbine, there is a risk, particularly in the case of supercharged engines, that the high temperatures in the turbine will result in varnish deposits which are harmful to the turbocharger.

For this reason, the possibility of using an open crankcase ventilation is used with this type of engine. Here, the crankcase gases are discharged to the outside. As described above, these gases still contain oil despite pre-separation and oil can also escape. In the present invention, a drain pan connected to the vent pipe provides a remedy.

The invention is based on creating an oil return device that connects a collection container 4 to the ventilation pipe 3 in such a way that a large ventilation cross-section is created at the top of the collection container 4, the collection container 4 being connected to the crankcase 1 with an oil return device 7 in such a way that between the collection container 4 and the crankcase 1 in the oil return device 7, a check valve 6, z. B. is arranged in the form of a spring / ball valve.

The large ventilation cross-section at the top of the collection container is created by a cover 5, a so-called shielding cap, which protrudes over the edge of the collection container 4.

This projection is designed in such a way that it is tight against the ingress of dust and liquid. It is located between the collection container 4 and cover 5, due to the loose fit, a sealing labyrinth.

This is done by a labyrinth seal with or without other measures such. B. the use of a sealing or random fiber fleece, which is not explicitly shown in the figure.

The collection container 4 has a connection to the cylinder crankcase 1. This connection is provided with a non-return valve 6.

The height of the collection container 4 is selected so that the check valve 6 opens in certain load situations of the motor or the internal combustion engine 8, e.g. B. when the engine is stopped, so that the ventilation oil collected in the collecting tank 4 is fed back to the engine 8 .

Thus, the open crankcase ventilation 2 is maintenance-free, without releasing oil or oil mist into the environment.

reference list

1

crankcase

2

Crankcase ventilation

3

vent pipe

4

collection container

5

cover/shielding cap

6

check valve

7

oil return device

8th

engine/engine

9

cylinder head

Claims (9)

Supercharged internal combustion engine (8) with an open crankcase ventilation, comprising at least one crankcase (1), at least one crankcase ventilation (2), at least one collecting container (4) and at least one oil return device (7), and wherein the collecting container (4) has a cover (5) has, which protrudes over the edge of the collecting container (4). internal combustion engine claim 1 , characterized in that the crankcase ventilation (2) is arranged essentially in the region of a cylinder head (9). Internal combustion engine according to one of the preceding claims, characterized in that the collection container (4) and the crankcase ventilation (2) are connected by means of at least one ventilation pipe (3). Internal combustion engine according to one of the preceding claims, characterized in that the collecting container (4) is connected to the ventilation pipe (3) in such a way that a ventilation cross-section is produced on the collecting container (4) which corresponds to two to five times the diameter of the ventilation pipe (3). internal combustion engine claim 4 , characterized in that the collection container (4) is connected to the ventilation pipe (3) in such a way that the collection container (4) has a ventilation cross-section which corresponds to three to four times the diameter of the ventilation pipe (3). Internal combustion engine according to one of the preceding claims, characterized in that the overhang of the cover (5) on the collection container (4) is designed in such a way that it is sealed with respect to dust and liquid entering. Internal combustion engine according to one of the preceding claims, characterized in that the collecting tank (4), in particular on the bottom of the collecting tank, has a return connection in the form of the oil return device (7) to the crankcase (1). internal combustion engine claim 7 , characterized in that a check valve (6) is arranged in this return connection. Method for operating an internal combustion engine, characterized in that an internal combustion engine (8) according to one of the preceding claims is used, the open crankcase ventilation (2) of which is operated maintenance-free without releasing oil or oil mist into the environment.

Images