EP3020934A1 - Crankcase ventilation apparatus - Google Patents

Abstract

The invention relates to a vehicle having an internal combustion engine (22), which has a crankcase (14) and a charging device (24), with a crankcase ventilation device (10) having at least one inertia-based oil separation device (11) with at least one inertia-based oil separator (12). a separated oil to the crankcase (14) recirculating oil return (81) and a suction jet pump (16) which is driven with compressed air (28) of the charging device (24) and which generates a negative pressure to drive blow-by gas. It is essential to the invention that the crankcase ventilation device (10) comprises a pump control valve (18) which regulates and / or controls the flow of compressed air (28) through the suction jet pump (16) and which has a closure member (34) against a valve seat (34). 32) is subjected to force and is lifted in excess of a pressure difference between a valve inlet (35) and a valve outlet (37) or upon exceeding an input side pressure against the force from the valve seat (32), so that the pump control valve (18) is opened.

Description

The invention relates to a vehicle having an internal combustion engine having a crankcase and a supercharger with a crankcase ventilation device having an inertia-based oil separator having at least one inertia-based oil separator, a separated oil to the crankcase returning oil return and a suction jet pump driven with compressed air of the supercharger and which generates a negative pressure to drive blow-by gas.

Most motor vehicles are equipped with an internal combustion engine, which usually provides for the drive of the vehicle. Such an internal combustion engine, preferably when it is designed as a piston engine, has a crankcase. In the crankcase is a crankshaft, which is connected via connecting rods with pistons of the individual cylinders of the internal combustion engine. Leakages between the pistons and the associated cylinder walls result in a blow-by gas flow through which blow-by gas passes from the combustion chambers into the crankcase. To avoid undue overpressure in the crankcase, modern internal combustion engines are equipped with a crankcase ventilation device to remove the blow-by gases from the crankcase.

To reduce pollutant emissions, the blow-by gas is usually supplied to a fresh air system of the internal combustion engine using the crankcase ventilation device, which supplies the combustion chambers of the internal combustion engine with fresh air. In the crankcase there is an oil mist, so that the blow-by gas carries oil with it. This oil, as an oil droplet, can damage elements in the intake tract, such as a turbocharger. To these elements To protect and reduce oil consumption, the crankcase breather usually has an oil separator, and preferably an oil return, which returns the separated oil to the crankcase.

In crankcase ventilation systems, passive systems can basically be distinguished from active systems. Passive systems use the pressure difference between the crankcase and the negative pressure in the fresh air system to drive the blow-by gas. Active systems additionally generate a negative pressure for the extraction of the blow-by gas from the crankcase. As a result, a higher pressure difference can be used in the oil separation, so that the deposition is improved. In supercharged internal combustion engines, for example by a compressor or turbocharger, it is known to use a suction jet pump, which is driven by the compressed air of the supercharger and thus generates a negative pressure, with the aid of which a higher differential pressure can be generated.

In particular, in exhaust gas turbochargers, the response of the internal combustion engine, at part load or idle can significantly deteriorate because in the charger energy is withdrawn, if due to the low power of the engine anyway low energy is present.

From the WO 2013/017832 A1 For example, a crankcase ventilation device is known in which a negative pressure for venting the crankcase by means of a suction jet pump is generated. The suction jet pump is driven by compressed air from a turbocharger.

The present invention has for its object to provide for a vehicle of the type mentioned an improved embodiment, in particular characterized by a better response of the internal combustion engine. At the same time, a high efficiency with regard to the oil separation effect should be realized.

This object is achieved by the subjects of the independent claims. Advantageous embodiments are the subject of the dependent claims.

The invention is based on the general idea of designing the crankcase ventilation device such that the power of the suction jet pump automatically adjusts itself as needed. As a result, an improved crankcase ventilation can be achieved without additional control device without negatively influencing the response of the internal combustion engine. It is essential to the invention that the crankcase ventilation device comprises a pump control valve which regulates and / or controls the flow of the compressed air through the suction jet pump and which has a closure part which is force-loaded against a valve seat and if a pressure difference between a valve inlet and a valve outlet is exceeded is lifted out of the valve seat against the force, so that the pump control valve is opened. In this way, the pump control valve opens just when the charging device has generated a sufficiently high boost pressure. As a result, the tarnishing of the charging device, in particular of an exhaust-gas turbocharger, is not adversely affected. The suction jet pump is switched on in these operating states in which the charging device generates sufficient compressed air. Furthermore, these operating conditions in which the charging device generates a high boost pressure are also characterized by a high output of the internal combustion engine, in which large volume flows of blow-by gas reach the crankcase, so that the activation of the ejector pump in these states is particularly favorable.

An advantageous variant provides that the pump control valve is a self-medium actuated valve. As a result, no control line is required for controlling and / or regulating the pump control valve. There is no need to provide additional energy. Thus, a very simple and inexpensive construction can be achieved thereby.

In the description and the appended claims, a self-medium actuated valve is understood to mean a valve in which the medium to be controlled is the same medium as the valve controlling medium. Examples of self-medium operated valves are check valves and pressure relief valves.

A favorable possibility provides that the force with which the closure part is acted upon against the valve seat is a spring force. Spring loaded valves are particularly easy to manufacture and are reliable in operation.

Another favorable possibility provides that the force with which the closure part is acted upon against the valve seat is a magnetic force. The use of magnetic forces offer on the one hand a possibility of contactless power transmission and on the other hand, the magnetic forces can be additionally influenced by electromagnets, so that the behavior of the pump control valve can be adapted and / or influenced.

A particularly favorable possibility provides that the force with which the closure part is acted upon against the valve seat is a pneumatic force generated by a pressure. Such a pneumatic force can be generated, for example, by a gas-filled membrane-covered cavity, or by a gas-filled cylinder. This pneumatically generated force is similar to the force of a spring proportional to the deflection, so that the Pump control valve can be conveniently adapted to the crankcase ventilation device.

Another particularly favorable possibility provides that the pump control valve is a proportional valve, wherein the pump control valve can continuously between a closed position in which the pump control valve is closed, and a passage position in which the pump control valve is fully open, can be. In this way, a continuous control and / or regulation of the suction jet pump is possible, so that the power of the suction jet pump can be conveniently adapted to the available boost pressure of the charging device.

An advantageous solution provides that the Ölabscheideeinrichtung has at least three working areas, wherein in a first working area, a flow cross section of the Ölabscheideeinrichtung is constant, wherein in a second work area of the flow cross section of the oil separator increases with increasing pressure difference between the inlet and outlet of the Ölabscheideeinrichtung and wherein in a third Working area of the flow cross section of the oil separator with increasing pressure difference increases less than in the second work area. Advantage see above.

A further advantageous solution provides that the inertia-based Ölabscheideeinrichtung has at least two inertia-based oil separator, and in particular a control device switches depending on the power of the ejector between the at least two oil separators. In this way, one of the oil separators can be designed for low volume flows and low pressures, while the second oil separator is designed for larger pressure differences, which can be achieved when the ejector is switched on. In this way, better deposition rates can be achieved.

A particularly advantageous possibility provides that the Ölabscheideeinrichtung comprises two oil separator, each having a spring-loaded poppet valve, which opens with increasing input-side pressure, that the poppet valve of one of the oil separator is a low pressure poppet valve, and that the poppet valve of the other oil separator is a high pressure poppet valve that the low pressure poppet valve opens at a lower pressure than the high pressure poppet valve. In this way, both with and without the support of the ejector a good oil separation rate can be achieved.

Another particularly advantageous possibility provides that the high-pressure poppet valve opens only at a pressure at which the low-pressure poppet valve is already open to the maximum. In this way, the two work areas of Ölabscheideeinrichtung are particularly well separated.

It is advantageous if the inertia-based oil separation device has an oil separator with a pressure / volume characteristic with at least three, preferably at least four, different regions. The different regions differ in particular by the relation between pressure and volume, for example, the different regions of the pressure / volume characteristic correlate with the different working regions of the oil separator.

Further, it is advantageous if the oil separator has two springs which act on the poppet valve, wherein a first spring is biased in the closed state of the poppet valve and a second spring is tensioned only from a certain opening path of the poppet valve. In this way, the three working areas of the oil separator can be easily achieved, namely in the first working area, the poppet valve is closed, in the second work area is the Poppet valve open and acted upon only by the force of the first spring and in the third working range, the poppet valve is acted upon by both the force of the first spring and the force of the second spring.

Furthermore, it is particularly advantageous if the impactor has a progressive spring, which acts on the poppet valve and which has a spring constant, which increases with increasing compression of the spring. In this way, also the behavior of the oil separator can be influenced in such a way that when connecting the ejector a greater pressure difference can be achieved, which allows a better Ölabscheiderate.

An advantageous variant provides that the one or more oil separators is or are formed by an impactor, and / or is formed by a cyclone or are. An impactor and a cyclone are both inertia-based oil separators that achieve an improved separation rate with an increased pressure difference between inlet and outlet. Thus, the effects of the suction jet pump can be optimally utilized.

A further advantageous variant provides that the poppet valve is additionally acted upon by a reference pressure, which acts on the poppet valve in the closing direction. Also in this way can be achieved that the pressure difference between the inlet and outlet of the oil separator is increased in order to achieve a better oil separation.

It is favorable if the oil separator has a membrane against which the reference pressure is applied and through which the poppet valve of the oil separator is acted upon. Thus, a force generated by the reference pressure can be applied to the poppet valve in a simple manner,

It is advantageous if the reference pressure is a boost pressure of the charging device or an input-side pressure of the suction jet pump. As a result, a high differential pressure in the oil separator is produced, in particular at high power of the suction jet pump, so that the support of the suction jet pump for crankcase ventilation in particular also leads to an increase in the oil separation rate.

In the description and the appended claims, under an input side pressure of the suction jet pump, the pressure of the gas flow that drives the suction jet pump is understood at the inlet of the suction jet pump.

It is particularly advantageous if the reference pressure is an ambient pressure, in particular an atmospheric ambient pressure. The ambient pressure is substantially constant, so that a vacuum generated by the suction jet pump, which acts as a back pressure to the reference pressure on the membrane, can influence the poppet valve. In particular, the vacuum is lowered with increasing power of the suction jet pump, so that less strong opening forces act on the poppet valve by the negative pressure. Consequently, with an increased output of the ejector, the opening area of the oil separator is reduced, so that the pressure difference across the oil separator can increase and thus the oil separation is improved.

A particularly advantageous variant provides that the crankcase ventilation device has a throttle valve, with which the blow-by gases can be throttled. If the negative pressure generated by the suction jet pump or the negative pressure generated by the internal combustion engine become too large, so that the pressure within the crankcase falls too far and there is a risk of sucking oil out of the crankcase, the throttle valve is closed, so that suction of oil from the crankcase can be prevented.

A further particularly advantageous variant provides that the throttle valve is arranged in a flow path of the blow-by gases between the crankcase and the Ölabscheideeinrichtung, or that the throttle valve is disposed in a flow path of the blow-by gases between the oil separator and the suction jet pump , In these two positions, the throttle valve can effectively prevent too much suction of the blow-by gases.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments of the invention are illustrated in the drawings and will be described in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components.

Fig. 1

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung,

Fig. 2

eine Schnittdarstellung einer Saugstrahlpumpe mit einem Pumpensteuerventil,

Fig. 3

eine Schnittdarstellung einer Ölabscheideeinrichtung mit daran angeschlossener Saugstrahlpumpe,

Fig. 4

eine Schnittdarstellung durch die Ölabscheideeinrichtung, wobei ein Tellerventil der Ölabscheideeinrichtung teilweise geöffnet ist,

Fig. 5

ein Diagramm, wobei einen Strömungsquerschnitt der Ölabscheideeinrichtung über einen Differenzdruck zwischen Ventileinlass und Ventilauslass des Tellerventils der Ölabscheideeinrichtung dargestellt ist,

Fig. 6

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer zweiten Ausführungsform der Erfindung,

Fig. 7

eine Schnittdarstellung durch eine Ölabscheideeinrichtung gemäß der zweiten Ausführungsform,

Fig. 8

ein Diagramm, wobei der Strömungsquerschnitt der Ölabscheideeinrichtung gegenüber einer Druckdifferenz zwischen Ventileingang und Ventilausgang des Tellerventils der Ölabscheideeinrichtung dargestellt ist,

Fig. 9

eine Prinzipdarstellung einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß eines dritten Ausführungsbeispiels,

Fig. 10

eine Schnittdarstellung durch eine Ölabscheideeinrichtung mit daran angeschlossener Saugstrahlpumpe gemäß der dritten Ausführungsform,

Fig. 11

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer vierten Ausführungsform,

Fig. 12

eine Schnittdarstellung durch eine Ölabscheideeinrichtung gemäß der vierten Ausführungsform,

Fig. 13

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer fünften Ausführungsform,

Fig. 14

eine Schnittdarstellung durch eine Ölabscheideeinrichtung gemäß der fünften Ausführungsform,

Fig. 15

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer sechsten Ausführungsform der Erfindung,

Fig. 16

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer siebten Ausführungsform,

Fig. 17

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer achten Ausführungsform,

Fig. 18

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer neunten Ausführungsform,

Fig. 19

eine Schnittdarstellung durch eine Ölabscheideeinrichtung gemäß der neunten Ausführungsform,

Fig. 20

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer zehnten Ausführungsform, und

Fig. 21

eine Prinzipskizze einer Brennkraftmaschine mit einer Kurbelgehäuseentlüftungseinrichtung gemäß einer elften Ausführungsform.

It show, each schematically

Fig. 1

a schematic diagram of an internal combustion engine with a crankcase ventilation device,

Fig. 2

a sectional view of a suction jet pump with a pump control valve,

Fig. 3

a sectional view of a Ölabscheideeinrichtung with attached suction jet pump,

Fig. 4

a sectional view through the Ölabscheideeinrichtung, wherein a poppet valve of the Ölabscheideeinrichtung is partially open,

Fig. 5

a diagram, wherein a flow cross section of the Ölabscheideeinrichtung is shown via a differential pressure between the valve inlet and the valve outlet of the poppet valve of the oil separator,

Fig. 6

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a second embodiment of the invention,

Fig. 7

a sectional view through an oil separator according to the second embodiment,

Fig. 8

a diagram, wherein the flow cross section of the Ölabscheideeinrichtung against a pressure difference between the valve inlet and the valve outlet of the poppet valve of the oil separator is shown,

Fig. 9

a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a third embodiment,

Fig. 10

a sectional view through a Ölabscheideeinrichtung connected thereto suction jet pump according to the third embodiment,

Fig. 11

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a fourth embodiment,

Fig. 12

a sectional view through an oil separator according to the fourth embodiment,

Fig. 13

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a fifth embodiment,

Fig. 14

a sectional view through an oil separator according to the fifth embodiment,

Fig. 15

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a sixth embodiment of the invention,

Fig. 16

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a seventh embodiment,

Fig. 17

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to an eighth embodiment,

Fig. 18

1 is a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a ninth embodiment,

Fig. 19

a sectional view through an oil separator according to the ninth embodiment,

Fig. 20

a schematic diagram of an internal combustion engine with a crankcase ventilation device according to a tenth embodiment, and

Fig. 21

a schematic diagram of an internal combustion engine with a crankcase ventilation device according to an eleventh embodiment.

An in FIG. 1 shown crankcase ventilation device 10 has a Flüssigkeitsabscheideeinrichtung 11, hereinafter called Ölabscheideeinrichtung 11 through which blow-by gases are passed from a crankcase 14 to separate oil mist from the blow-by gas, a suction jet pump 16 which generates a negative pressure to the To drive blow-by gases, and a pump control valve 18, which controls the suction power of the ejector 16 and / or regulated. The crankcase ventilation device 10 is used for venting the crankcase 14 of an internal combustion engine 20, as used for example in a vehicle 22, in particular a motor vehicle.

In reciprocating engines, such as gasoline engines or diesel engines, due to the high pressure during combustion gases from the combustion chamber into the crankcase 14. The gases flow between the piston and cylinder wall in the crankcase 14. These gases are blow-by Called gases. The blow-by gases would accumulate in the crankcase 14 over time and build up considerable pressure. To prevent this, the crankcase ventilation device 10 is provided.

Since the blow-by gases, which are vented from the crankcase 14, usually have oil mist, they are the intake manifold 13 of the engine 20 is supplied. In order not to burden the internal combustion engine 20 and possibly in the intake tract 13 befindlicher units, such as superchargers 24 with the oil mist, the oil separator 11 is provided. The Ölabscheideeinrichtung 11 causes a pressure difference, or requires a certain pressure difference in order to achieve sufficiently high deposition rates. For this reason, for example, in pure suction internal combustion engines, the negative pressure in the intake tract 13 of the internal combustion engine 20 is utilized in order to provide a pressure difference for the oil separation device 11. In supercharged internal combustion engines having, for example, a compressor or turbocharger 26, the ejector 16 may be provided which is driven by compressed air 28 generated by the supercharger 24 and generates a negative pressure. Thus, a larger pressure difference between the crankcase 14 and the outlet of the oil separator 11 can be generated. As a result, a better degree of separation can be achieved. This is particularly interesting because a maximum permissible pressure in the crankcase 14 should not be exceeded.

The removal of the compressed air 28 behind the charging device 24, however, leads to power losses of the internal combustion engine 20. In particular, when using a turbocharger 26, the response of the internal combustion engine 20 deteriorates, especially at low power. Thus, for example, at idle or at part-load, the turbocharger 26 is at a low speed, thus producing only a low boost 30. When compressed air 28 is still being extracted in such a situation to assist the crankcase ventilation device 10, engine performance becomes high reduced. In a higher load range or at full load, however, is the turbocharger 26 at full speed and can generate sufficient compressed air 28 and a sufficiently high boost pressure 30, so that often even a Waist Gate is used to avoid impermissibly high speeds of the turbocharger. In such situations, the removal of compressed air 28 is harmless to the performance of the engine 20.

The pump control valve 18 is designed such that the suction jet pump 16 is operated just when sufficient boost pressure 30 so are sufficient amounts of compressed air 28 from the supercharger 24 are available. Accordingly, the power of the ejector 16 is throttled or the ejector 16 completely turned off when not enough boost pressure 30 or compressed air 28 is available, for example, at idle or in partial load ranges of the engine 20th

Thus, the assistance of the crankcase ventilation by the suction jet pump 16 takes place just when the internal combustion engine 20 outputs high power. So just then, even if a flow rate of blow-by gases in the crankcase 14 is particularly high. Viewed the other way around, the throttling of the suction jet pump 16 takes place precisely in operating states of the internal combustion engine 20, when anyway relatively small amounts of blow-by gas reach the crankcase 14.

The pump control valve 18 is configured such that the pump control valve 18 opens or closes depending on a pressure difference between a valve inlet 35 and a valve outlet 37. At low pressure differences, the pump control valve 18 is closed. At pressure differences above a threshold pressure difference opens the pump control valve 18 so that gases can flow through the pump control valve. The pump control valve 18 is thus a eigenmediumbetätigter Valve is. As a result, no control line is required for controlling and / or regulating the pump control valve.

In the description and the appended claims, a self-medium actuated valve is understood to mean a valve in which the medium to be controlled is the same medium as the valve controlling medium. Examples of self-medium operated valves are check valves and pressure relief valves.

On the input side, the pump control valve 18 is connected to the high-pressure side of the charging device 24, so that the boost pressure 30 of the charging device 24 is present on the input side of the pump control valve 18. The pump control valve 18 thus opens when the boost pressure 30 of the charging device 24 exceeds the output pressure of the pump control valve 18, that is, the pressure at the inlet of the suction jet pump 16 by more than the threshold pressure difference. Thus, when the compressed air 28 is used to drive the ejector pump 16, the pump control valve 18 opens, if it is harmless to the performance of the engine 20.

Alternatively or additionally, it may be provided that the pump control valve 18 is designed such that it opens or closes depending on the input-side pressure. At low pressures up to a threshold pressure, the pump control valve 18 is closed. At pressures above the threshold pressure, the pump control valve 18 opens so that gases can pass through the pump control valve 18.

On the input side, the pump control valve 18 is connected to the high-pressure side of the charging device 24, so that the boost pressure 30 of the charging device 24 is present on the input side of the pump control valve 18. The pump control valve 18 thus opens when the boost pressure 30 of the charging device 24 above the threshold pressure is. Thus, when the compressed air 28 is used to drive the ejector pump 16, the pump control valve 18 opens, if it is harmless to the performance of the engine 20.

The pump control valve 18 has a valve seat 32 and a closure part 34, which is pressed against the force of the valve seat 32 and thus closes the pump control valve 18. On the valve seat 32, a seal 36 is arranged, against which the closure part 34 is pressed, and thus the pump control valve 18 closes.

The closure member 34 is arranged such that the input-side pressure exerts a force on the closure member 34, which lifts the closure member 34 from the valve seat 32. The force with which the closure member 34 is acted upon against the valve seat 32 and the pressure force by the boost pressure 30 thus compete with each other. When the pressing force of the boost pressure 30 exceeds the force with which the shutter member 34 is urged against the valve seat 32, the shutter member 34 rises from the valve seat 32, so that the pump control valve 18 opens. The pressure force by the boost pressure 30 is at the threshold pressure at which the pump control valve 18 opens approximately equal to the force with which the closure member 34 is acted upon against the valve seat 32.

To generate the force with which the closure member 34 is acted upon against the valve seat 32, several possibilities come into question. For example, a spring 38 may be provided, which is biased, so that the closure member 34 is acted upon by the spring force of the spring 38 against the valve seat 32.

Furthermore, it is also possible to utilize magnetically or pneumatically generated forces.

The suction jet pump 16 is based on the Ventury effect. A first medium is passed through a nozzle and directed into a larger tube. Due to the high flow rate of the medium at the nozzle, the surrounding medium is entrained, so that there is a negative pressure, which is utilized here in order to achieve a sufficient pressure difference at the Ölabscheideeinrichtung 11.

The oil separator 11 has an oil separator 12, which is an inertia-based oil separator. Such inertia-based oil separator is also suitable for the separation of other liquid conductors, such as water. The oil separator 12 exploits the different densities of the oil droplets compared to the density of the blow-by gas to separate the oil droplets from the blow-by gas. Usually, a gas flow is generated, which is deflected. The oil droplets can not follow so well due to the higher density of the deflection, so that they are driven to the edge of the flow and possibly hit a plate on which they attach. Such inertia-based oil separators 12 are, for example, impactors 40 or cyclones.

The oil separator 12 is designed as an impactor 40 and can also separate other liquids. In an impactor 40, the gas flow to be cleaned, for example the blow-by gas, is passed through at least one nozzle 42, which is arranged opposite a baffle plate 44, so that the gas flow is deflected immediately after the nozzle. Through the nozzle 42, the gas flow receives a high velocity, so that the liquid droplets, hereinafter called oil droplets, the deflection by the baffle plate can not follow and meet the baffle plate 44 and hang there and thus be separated from the gas flow.

Furthermore, the impactor 40 has a poppet valve 46 which is spring-loaded closed, wherein the poppet valve 46 opens when a pressure difference between the valve inlet 48 and valve outlet 50 is exceeded, which corresponds to a pressure difference between inlet 49 and outlet 51 of the oil separator 11. In this case, the poppet valve 46 forms an annular flow gap 52, which also acts like a nozzle, and accelerates the flow of gas flowing through the impactor 40, for example the blow-by gas. The annular flow gap 52 is surrounded by a cylindrical baffle plate 44, which deflects the gas flow, which has flowed through the annular flow gap 52, and thus also allows there a separation of oil droplets from the gas flow. Characterized in that the poppet valve 46 opens at an increasing pressure difference, a flow cross-section 56 of the impactor 40 is increased and thus increases the flow cross-section of the oil separator 11. The flow cross section 56 is composed of the cross section of all nozzles 42 and the flow area of the annular flow gap 52.

Due to the fact that the flow cross-section 56 of the impactor 40 increases from a certain differential pressure threshold, the pressure drop within the impactor increases less with increasing volume flow from a certain pressure. It can thereby be achieved that, as early as possible, even at low volumetric flows of the blow-by gases, a differential pressure which is sufficiently high for the oil separation rests against the impactor 40 and at the same time the differential pressure does not increase so much that the venting of the crankcase 14 ceases can be guaranteed.

By supporting the suction jet pump 16, larger pressure differences at the impactor 40 can, however, be accepted in the case of the crankcase ventilation device 10 according to the invention. That's why the poppet valve is 46 formed in such a way that the poppet valve 46 can be opened more easily via a first opening path than over a remaining opening path. This is achieved for example in that the poppet valve 46 has two springs which press a closure plate 58 against a valve seat, wherein when the poppet valve is closed, a first spring 60 is biased and a second spring 62 is not biased. The second spring 62 is tensioned only when opening the poppet valve 46 when the first opening path of the poppet valve 46 is passed. In this way, the relevant for the poppet valve 46 spring constant in the first opening path is less than in the remaining opening stroke, since the spring constants of the first spring 60 and the second spring 62 are added.

In this way, the impactor 40 has three working areas. In a first working area 64, the poppet valve 46 is closed and the gas flow must flow through the nozzles 42. In a second work area 66, the poppet valve 46 is partially opened, with only the first spring 60 is tensioned, so that the poppet valve 46 can open against a small spring constant. In a third working area 68, the poppet valve 46 is opened so far that both the first spring 60 and the second spring 62 are tensioned, so that a further opening of the poppet valve 46 must be made against an increased spring force.

The working areas are preferably selected such that when the ejector pump 16 is switched off or operating at very low power, the impactor 40 operates in the first working range or in the second working range 66 and when the suction switching pump 16 is switched on, the impactor 40 operates in the third working range 68.

The impactor 40 has an input side inner cylinder 70, in which at a head end 72 of the inner cylinder 70, the nozzles 42 in the cylinder wall are arranged and directed radially outward. At the head end 72 flow openings 74 are arranged for the poppet valve 46 through which the gas flow through the poppet valve 46 can flow and on the other hand, a central bore 76 in which a guide pin 78 of the poppet valve 46 is guided so that a closure plate 58 axially movable is mounted in the inner cylinder 70.

The shutter 58 abuts against the head end 72 of the inner cylinder 70 from the outside and thus closes the flow openings 74 when the poppet valve 46 is closed. The shutter 58 is axially raised from the head end 72 of the inner cylinder 70 to expose the flow opening 74 when the poppet valve 46 is opened.

An annular plate element, on which the springs 60, 62 can engage in order to press the closure plate 58 against the flow openings 74, is fastened to the guide pin 78 at the end facing away from the closure plate 58.

The springs 62, 60 are supported on an inner side of the inner cylinder 70 at the head end 72 of the inner cylinder 70 and thus press the plate-shaped closure member 58 in the direction of the valve inlet 48. Radially outside the inner cylinder, the baffle plate 44 is cylindrical and arranged and Thus, the gas flow, which flows through the nozzles 42 or through the annular flow gap 52 and thus divert fluid, such as oil, to separate from the gas flow.

Furthermore, the impactor 40 has a liquid collecting region 80, in which the separated liquid, for example oil, is collected in order to then be able to return it to the crankcase 14 via an oil return 81. Fluidically between the crankcase 14 and the impactor 40, a throttle valve 15 is arranged, which can throttle the flow of the blow-by gases, if the pressure in the crankcase 14 would decrease too much, so that oil would be sucked out of the crankcase 14. Alternatively or additionally, the throttle valve 15 may also be arranged fluidically between the oil separation device of the suction jet pump 16.

One in the FIGS. 6 to 8 illustrated second embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10 in that the poppet valve 46 of the impactor 40 has a progressive spring 82, with which the plate-shaped closure member 58 of the poppet valve 46 is subjected to force against the flow openings 74.

In this way, the second working area 66 and the third working area 68 of the impactor 40 continuously merge into one another, so that when the suction jet pump 16 is switched on, an increased pressure difference at the impactor 40 can be achieved.

Incidentally, the right in the FIGS. 6 to 8 illustrated second embodiment in terms of structure and function with in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

One in the FIGS. 9 to 10 illustrated third embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10 characterized in that the oil separator 11, two oil separator 12, for example has two impactors 40 through which the oil separator 11 has a plurality, for example, three work areas.

The Ölabscheideeinrichtung 11 has a first poppet valve 84 and a second poppet valve 86, wherein both poppet valves each have only one spring. Wherein the spring 88 of the first poppet valve 84 has a lower spring constant than the spring 90 of the second poppet valve 86. Further, the bias of the spring 90 of the second poppet valve 86 is such that the second poppet valve 86 opens only when the first poppet valve 84 already is open at most. The first poppet valve 84 is also called the low pressure poppet valve 84, and the second poppet valve 86 is also called the high pressure poppet valve 86.

In this way, the first working area 64 of the oil separation device 11 results, in which both the first poppet valve 84 and the second poppet valve 86 are closed, and the oil separation device 11 can flow through the gas flow only through the nozzles 42. Furthermore, the second working area 66 is characterized in that the first poppet valve 84 is partially opened and the second poppet valve 86 is closed. The third working area 68 is characterized in that the first poppet valve 84 is fully open and that the second poppet valve is at least partially open. Thereby, the same behavior of the oil separator 11 as in the first two embodiments can be achieved.

Incidentally, the right in the FIGS. 9 to 10 illustrated third embodiment of the crankcase ventilation device 10 in terms of design and function with in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

One in the FIGS. 11 and 12 illustrated fourth embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10 characterized in that the poppet valve 46 is additionally acted upon by a reference pressure 92 which presses the poppet valve 46 in a closed position.

As a reference pressure 92, for example, the boost pressure 30 he charging device 24 can be used. At high load pressures 30, the suction power of the ejector 16 is particularly high, so that the oil separator 11, a high pressure difference for the oil separation can be provided. In order to make optimum use of this, the flow cross-section 56 of the oil separator 11 must not be too large. This is achieved by the reference pressure 92, since with larger boost pressures 30, the poppet valve 46 may be closed again, so that the flow cross-section 56 of the oil separation device 11 increases or even decreases less.

Alternatively, it may be provided that an input-side pressure 93 of the suction jet pump 16 is used as the reference pressure 92. The input-side pressure of the ejector jet 16 16 is also a measure of the performance of the ejector 16, so that the adjustment of the oil separator 11 is particularly adapted to the actually available suction power of the ejector 16 even with regulation of the power of the ejector 16 by the pump control valve ,

Furthermore, it can alternatively be provided that an atmospheric ambient pressure is used as the reference pressure 92. The ambient pressure is essentially constant and only subject to fluctuations due to the altitude above zero and the weather-related fluctuations.

The impactor 40 has in a free space above the closure plate 58 of the poppet valve 46 a closed by a membrane 94 pressure chamber in which the reference pressure 92 is introduced. The diaphragm 94 presses driven by the reference pressure 92 on the shutter 58. The shutter 58 is thereby additionally pressed onto the flow openings 74 of the poppet valve 46.

As a back pressure to the reference pressure 92, the pressure at the valve outlet 50 is applied to the membrane 94, which thus acts on the poppet valve 46 in the opening direction. The outlet 51 of the oil separator 11 and thus the valve outlet 51 is sucked off by the suction jet pump 16 so that the vacuum generated by the suction jet pump 16 is applied to the valve outlet 51. At high powers of the ejector 16 thus reduces the pressure that opens the poppet valve 46, so that when increasing the power of the ejector 16, the poppet valve 46 is acted upon more strongly in the closing direction. This also applies when using a substantially constant pressure as the reference pressure 92, such as the atmospheric pressure.

Furthermore, the pressure at the valve inlet 48 acts on the poppet valve 46 in the opening direction. The pressure at the valve inlet 48 is in particular at the bottom of the plate 58 and at the top of the guide pin 78 at. The pressure at the valve inlet substantially corresponds to the pressure in the crankcase 14.

Accordingly, there are three competing pressures on the poppet valve 46, namely the reference pressure which acts on the poppet valve 46 in the closing direction, the negative pressure generated by the suction jet pump 16 and the pressure in the crankcase, which act on the Telelrventil 46 in the opening direction.

Incidentally, the right in the FIGS. 11 and 12 illustrated fourth embodiment of the crankcase ventilation device 10 in terms of design and function with in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

One in the Figures 13 and 14 illustrated fifth embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 9 to 10 illustrated third embodiment of the crankcase ventilation device 10 characterized in that the first poppet valve 84, so the low pressure poppet valve 84, in addition to a reference pressure 92 is applied.

In this way, for example, a switching of the oil separator 11 from the first poppet valve 84 to the second poppet valve 86 can be achieved. This switching can be done according to the power of the ejector 16.

As a reference pressure 92, for example, the boost pressure 30 of the charging device 24 can be used. At high boost pressures 30, the first poppet valve 84, which is formed as a low pressure poppet valve 84, is depressed by the reference pressure 92 so that the low pressure poppet valve 84 will be less widely opened or even closed. The liquid separation then takes place mainly through the high pressure poppet valve 86.

In this way, when the suction jet pump 16 is connected to the oil separation device 11, an even higher pressure difference for the oil separation can be made available.

The first poppet valve 84 has in a free space above the closure plate 58 of the poppet valve 84 a closed by a membrane 94 pressure chamber in which the reference pressure 92 is introduced. The diaphragm 94 is driven by the reference pressure 92 onto the closure plate 58. The closure plate 58 is thereby additionally pressed onto the flow openings 74 of the poppet valve 84.

Incidentally, the right in the Figures 13 and 14 illustrated fifth embodiment of the crankcase ventilation device 10 in terms of structure and function with in the FIGS. 9 to 10 represented third embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

An in FIG. 15 illustrated sixth embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10 in that the pump control valve 18 is controlled by a control device 96 and / or regulated.

The pump control valve 18 is designed to be controllable by a signal from the outside accordingly. For example, the pump control valve 18 is an electrically, magnetically, pneumatically or hydraulically controllable valve. Preferably, the pump control valve 18 can be switched between a closed position and an open position. However, it is also possible that the pump control valve 18 is a proportional valve, which is continuously adjustable between the closed position and the passage position.

The control device 96 controls the pump control valve 18 and thus the power of the suction jet pump 16 such that the response of the internal combustion engine 20 is influenced as little as possible. That is, the pump control valve 18 is closed, in particular during idling operation and / or partial load range, so that the suction jet pump 16 does not draw off compressed air 28 from the charging device 24.

Different possibilities are conceivable on the basis of which the control device 96 decides whether the suction jet pump 16 is switched on or off. By way of example, the control device can regulate and / or control the power of the suction jet pump 16 based on a map.

The control device 96 is, for example, the engine control of the internal combustion engine 20, so that the control device 96 has all the data of the engine control. These are in particular the rotational speed of the internal combustion engine 20, the torque generated by the internal combustion engine 20, the generated power of the internal combustion engine 20 or a throttle position. On the basis of these values, the control device 96 can estimate whether sufficient charge pressure 30 is present, so that the performance of the internal combustion engine 20 is not or only slightly influenced and if any support of the crankcase ventilation by the suction jet pump 16 is necessary.

Furthermore, the controller 96 may regulate and / or control the ejector 16 in accordance with a measured amount. Such quantities may be, for example, the intake air quantity, the boost pressure 30 or the pressure in the crankcase 14. In this way, the suction jet pump can respond to the conditions actually occurring in the crankcase 14 or behind the charging device 24, and control the ejector 16 accordingly.

It is understood that a combination of map-based control and / or control and based on measured sizes is possible. For example For example, a value for the output of the suction jet pump can first be determined on the basis of the characteristic diagrams and, if appropriate, readjusted on the basis of the measured variable.

Incidentally, in the FIG. 15 illustrated sixth embodiment of the crankcase ventilation device 10 in terms of design and function with in the FIGS. 1 to 5 illustrated first embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

An in FIG. 16 illustrated seventh embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 6 to 8 illustrated second embodiment of the crankcase ventilation device 10 characterized in that the pump control valve 18 is controlled by a control device 96. The control and / or control of the pump control valve 18 by the control device 96 corresponds to the control and / or control according to the in FIG. 15 illustrated sixth embodiment of the crankcase ventilation device 10, the above description of which reference is made.

Incidentally, the in FIG. 16 shown seventh embodiment of the crankcase ventilation device 10 in terms of structure and function with in the FIGS. 6 to 8 illustrated second embodiment of the crankcase ventilation device 10 in terms of structure and function, to the above description in this respect reference is made.

An in FIG. 17 illustrated eighth embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 9 to 10 illustrated third embodiment of the crankcase ventilation device 10th in that the pump control valve 18 is controlled and / or controlled by a control device 96. The control and / or control of the pump control valve 18 by the control device 96 corresponds to the control and / or control according to the in FIG. 15 illustrated sixth embodiment of the crankcase ventilation device 10, the above description of which reference is made.

Incidentally, the in FIG. 17 illustrated eighth embodiment of the crankcase ventilation device 10 with respect to structure and function with the illustrated in Figures 9 to 10 third embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

One in the Figures 18 and 19 illustrated ninth embodiment of the crankcase ventilation device 10 differs from the in FIG. 17 illustrated eighth embodiment of the crankcase ventilation device 10 in that the crankcase ventilation device 10 has a switching valve 100 which switches the blow-by gas flow between the two impactors of the oil separator 11. The switching valve 100 is controlled by the controller 96. The control device 96 switches the switching valve 100 according to that the impactor 40 is flowed through with the low pressure poppet valve 84, when the ejector 16 is turned off or only at very low power, and that the high pressure poppet valve 86 is flowed through when the ejector pump 16 is turned on or at least at high Performance works.

As a result, precisely when the suction jet pump 16 assists the crankcase ventilation and thus a high pressure difference for oil separation is available, the high-pressure poppet valve 86 of the oil separation device can be targeted used, which requires a higher differential pressure, but then also offers a better oil separation.

Further, the controller 96 controls another valve 102 disposed between the impactor 40 with the low pressure poppet valve 84 and the intake manifold 13, and then closes when the switch valve 100 is switched to the impactor 40 with the high pressure poppet valve 86. In this way, backflow of gases through the impactor 40 with the low cell valve 84 can be avoided. In this case, the Ölabscheideeinrichtung 11 for both impactors each have their own outlet 53, 55 on.

Incidentally, the right in the Figures 18 and 19 illustrated ninth embodiment of the crankcase ventilation device 10 in terms of design and function with in FIG. 17 illustrated eighth embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

An in FIG. 20 illustrated tenth embodiment of the crankcase ventilation device 10 differs from that in the FIGS. 11 and 12 illustrated fourth embodiment in that the pump control valve 18 is controlled by a control device 96. The control and / or control of the pump control valve 18 by the control device 96 corresponds to the control and / or control according to the in FIG. 15 illustrated sixth embodiment of the crankcase ventilation device 10, the above description of which reference is made.

Incidentally, the in FIG. 20 illustrated tenth embodiment of the crankcase ventilation device 10 in terms of design and function with in the FIGS. 11 and 12 illustrated fourth embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

An in FIG. 21 illustrated eleventh embodiment of the crankcase ventilation device 10 differs from that in the Figures 13 and 14 illustrated fifth embodiment of the crankcase ventilation device 10, characterized in that the pump control valve 18 is controlled and / or regulated by a control device 96. The control and / or control of the pump control valve 18 by the control device 96 corresponds to the control and / or control according to the in FIG. 15 illustrated sixth embodiment of the crankcase ventilation device 10, the above description of which reference is made.

Incidentally, the in FIG. 21 illustrated eleventh embodiment of the crankcase ventilation device 10 in terms of structure and function with in the Figures 13 and 14 illustrated fifth embodiment of the crankcase ventilation device 10, to the above description in this respect reference is made.

Claims (14)

A vehicle having an internal combustion engine (22) having a crankcase (14) and a supercharger (24) with crankcase ventilation means (10) including at least one inertia - based oil separator (11) having at least one inertia - based oil separator (12), a separated oil Crankcase (14) recirculating oil return (81) and a suction jet pump (16) which is driven with compressed air (28) of the charging device (24) and which generates a negative pressure to drive blow-by gas, characterized
in that the crankcase ventilation device (10) comprises a pump control valve (18) which regulates and / or controls the flow of the compressed air (28) through the suction jet pump (16) and which has a closure part (34) which acts against a valve seat (32) is arranged and is lifted in excess of a pressure difference between a valve inlet (35) and a valve outlet (37) or at an input side pressure against the force from the valve seat (32), so that the pump control valve (18) is opened. Vehicle according to claim 1,
characterized,
that the pump control valve (18) is a self-medium operated valve. Vehicle claim 1 or 2,
characterized,
that the force with which the closure member (34) against the valve seat (32) is acted upon a spring force is a magnetic force and / or is of a pneumatic pressure generated force. Vehicle according to one of claims 1 to 3,
characterized, - That the pump control valve (18) is a proportional valve, wherein the pump control valve (18) continuously between a closed position in which the pump control valve (18) is closed, and a passage position in which the pump control valve (18) is fully open, can be located , Vehicle according to one of claims 1 to 4,
characterized, - That the Ölabscheideeinrichtung (11) has at least three working areas (64, 66, 68), wherein a flow cross section (56) of the oil separation device (11) is constant in a first working region (64), - In a second work area (66) of the flow cross section (56) of the oil separation device (11) increases with increasing pressure difference between the inlet (49) and outlet (61) of the oil separation device (11) and - In a third working area (68) of the flow cross-section (56) of the oil separation device (11) increases less with increasing pressure difference than in the second working area (68). Vehicle according to one of claims 1 to 5,
characterized,
in that the oil separation device (11) has at least two inertia-based oil separators (12) and, in particular, switches over a control device (96) between the at least two oil separators (12), depending on the power of the suction jet pump (16). Vehicle according to claim 1 or 6,
characterized, - That the one or more oil separator (12) is or are formed by an impactor (40), and / or - is or are formed by a cyclone. Vehicle according to one of claims 1 to 7,
characterized,
that a poppet valve (46) of the oil separator (40) in addition to a reference pressure (92) is applied which urges the poppet valve (46) in the closing direction. Vehicle according to claim 8,
characterized,
in that the oil separator has a membrane (94) against which the reference pressure (92) bears and through which the poppet valve (46) of the oil separator (12) is acted upon. Vehicle according to claim 8 or 9,
characterized,
that the reference pressure (92) is an ambient pressure. Vehicle according to claim 8 or 9,
characterized,
that the reference pressure (92) is a load pressure (30) of the charging device (24). Vehicle according to claim 8 or 9,
characterized,
that the reference pressure (92) is an input-side pressure (93) of the suction jet pump (16). Vehicle according to one of claims 1 to 12,
characterized,
in that the crankcase ventilation device (10) has a throttle valve (15) with which the blow-by gases can be throttled. Vehicle according to claim 13,
characterized, - That the throttle valve (15) is arranged in a flow path of the blow-by gases between the crankcase (14) and the Ölabscheideeinrichtung (11), or - That the throttle valve (15) is arranged in a flow path of the blow-by gases between the Ölabscheideeinrichtung (11) and the suction jet pump (16).

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