EP3964698A1 - Distribution device for distributing fluid streams and method for operating a motor vehicle with a combustion engine - Google Patents

Abstract

Distribution device for distributing fluid streams, having a main channel and a plurality of outlet channels branching off from the main channel, the distribution device being designed to distribute a fluid stream entering the main channel to the outlet channels. An inner channel is arranged within the main channel, the inner channel being designed to conduct fluid penetrating the inner channel to at least one of the outlet channels and the distribution device having a shut-off element for shutting off a fluid flow entering the inner channel from the main channel.

Description

The invention relates to a distribution device for distributing fluid flows and a method for operating a motor vehicle with an internal combustion engine.

Piston cooling is used in modern combustion engines. Such a piston cooling can be implemented, for example, by using a fluid to cool the piston. The fluid can be a lubricating oil, for example. The fluid can be applied to the pistons by means of so-called piston cooling nozzles.

It is known from the prior art that piston cooling nozzles of this type can be switched off, for example in order to deactivate piston cooling in certain operating states in which piston cooling is not required. This can be done, for example, by means of pressure-controlled valves integrated into the piston cooling nozzles. If the valves are subjected to a pressure that exceeds a certain limit pressure, the valves open.

Alternatively, distribution devices for distributing fluid streams are known from the prior art, in which a fluid stream entering a main channel is distributed to a plurality of outlet channels branched off from the main channel. From the FR 3 023 319 A1 For example, a distribution device is known in which the fluid streams entering the outlet channels from the main channel can be shut off by means of a shut-off element. The shut-off takes place in such a way that by moving a shut-off element of the shut-off element, the outlet ducts branched off from the main duct are shut off at the same time.

Furthermore, from the KR 10 2011 006 2408 A a shut-off device is known which makes it possible to allow different flow rates by selectively shutting off or releasing two outlet channels branched off from a main channel, which outlet channels reunite after they have branched off from the main channel.

According to the prior art, however, there is the problem with such piston cooling that in internal combustion engines with cylinder deactivation a deterioration of the emission values occurs. In particular, increased particle formation can be observed when cylinders that were previously switched off are switched on again and thus fired.

The invention is therefore based on the object of demonstrating a distribution device for distributing fluid flows and a method for operating an internal combustion engine in which the problems described above do not occur or at least occur to a reduced extent.

The object is achieved by a distribution device for distributing fluid flows and a method for operating an internal combustion engine according to the independent claims. The dependent claims relate to advantageous embodiments.

The distribution device according to the invention for distributing fluid flows has a main channel and a plurality of outlet channels branched off from the main channel. In this case, the distribution device is designed to distribute a fluid flow entering the main channel to the outlet channels. The fluid can in particular be a lubricant and/or a coolant, for example a lubricating oil, which fulfills a cooling function in addition to its lubricating function.

According to the invention, an inner channel is arranged inside the main channel. The inner channel is configured to direct fluid entering the inner channel to at least one of the exit channels. The shut-off device has a shut-off element for shutting off a fluid flow entering the inner channel from the main channel.

This arrangement enables the fluid flow to the at least one outlet channel to which the fluid penetrating the inner channel is directed to be shut off in a targeted manner. Other outlet channels branched off from the main channel are not affected by the blocking of the fluid flow, i.e. the fluid flow entering the main channel continues to be distributed to these outlet channels. Only those outlet channels that are supplied with fluid through the inner channel are shut off by the shut-off element. In this context, it is advantageous if the outlet channels, to which the fluid penetrating into the inner channel is conducted, can be reached exclusively via the inner channel by the fluid penetrating into the main channel.

The distribution device can be designed in such a way that the fluid flow entering the inner channel from the main channel flows through the inner channel when passing through the main channel initially washed over. Such a configuration, in which the inner channel is positioned within the fluid flow in the main channel, offers the particular advantage that existing design concepts can be supplemented by the inner channel and the targeted blocking of at least one outlet channel branched off from the main channel. The flushing of the inner channel enables the outlet channels branched off from the main channel, which are not supplied with fluid via the inner channel, to continue to be able to be reached by the fluid flow.

Accordingly, the method according to the invention for operating an internal combustion engine provides that a shut-off element is used to interrupt a fluid flow directed to a piston to be cooled if the cylinder to which this piston belongs is not fired due to a cylinder deactivation, while at least the piston of another cylinder , which is being fired, is further cooled by means of a fluid flow branched off from the interrupted fluid flow.

The idea of shutting off the flow of fluid that is directed to the cylinder to cool the piston of this cylinder when a cylinder is switched off, and thus stopping the piston cooling of the switched-off cylinder, is based on the knowledge that this would reduce the adverse particle emission levels associated with the Cylinder deactivation could be observed, can be eliminated and/or at least reduced. The concept is based on the finding that when a cylinder is switched off, the piston cooling of the switched off cylinder causes the ring gap and ring land cross sections to deform due to the lack of combustion temperature in a way that leads to greater oil transport into the combustion chamber. In addition, the pressure in the combustion chamber drops due to the lack of combustion, which also promotes the oil transport from the crankcase to the combustion chamber. The result is increased particle emissions when the deactivated cylinder is put back into operation. This disadvantageous effect can be counteracted—at least to a certain extent—by switching off the piston cooling of the switched-off cylinder.

It goes without saying that the piston cooling of at least one cylinder can be switched off in particular by means of the distribution device described. This can be easily integrated, in particular, into existing design concepts, so that the method for operating an internal combustion engine can be carried out in an advantageous manner. In principle, however, it is also possible to selectively switch off the To enable piston cooling of individual cylinders depending on their cylinder deactivation using other technical devices.

It is also possible to use the distribution device described for selectively shutting off fluid flows other than those used for piston cooling. In this case, however, the distribution device is in particular a component part of a motor vehicle. The fluid streams routed to the individual outlet channels can be used, for example, to supply transmissions with a fluid. In this context, the shut-off function can be used in particular to supply these transmissions with the fluid as a function of specific driving conditions. This is particularly advantageous if it is a hybrid vehicle or a vehicle with a hybrid drive. In vehicles of this type, parts of the drive train, in particular the transmission, are temporarily not used, in particular when the motor vehicle is temporarily operated purely electrically or with a purely internal combustion engine. In these cases it is possible with the distribution device, depending on the corresponding operating state, to cool parts of the drive train, in particular individual transmissions, selectively as a function of the operating state.

It is possible that the inner channel is formed by a tube. The inner channel can in particular be pressed into the main channel. In this context, there is a cost-effective way of realizing the inner channel arranged inside the main channel. The tube that forms the inner channel can have branches that end at the branched outlet channels that are to be supplied with the fluid through the inner channel when the inner channel is in its intended position in the main channel. Furthermore, the inner channel can have spacer elements. These can be separate components; alternatively and/or additionally, the spacer elements can be molded onto the component that forms the inner channel, for example a tube. The spacer elements make it possible to press a pipe into the main duct, the outside diameter of which is smaller than the diameter of the main duct. This makes it possible for the fluid located in the main channel to flow around the inner channel.

The main channel can be formed by a cast component. Casting processes enable the cost-effective representation of components with comparatively complicated geometries. In this case, the channels can already have been produced during casting; alternatively and/or additionally, it is possible for the channels to be introduced into the component subsequently, for example in the form of bores. The advantage of the distribution device described is that, in contrast to comparable switchable distribution devices according to the the technology, in which the shut-off device is guided in the main duct, there are no high demands on the processing of the material surfaces that delimit the main duct. In particular when the inner channel is designed as a pressed-in tube, it is possible to press it, for example, into an unmachined or almost unmachined cast part.

The obturator can be plugged into the main channel. By plugging it into the main duct, the shut-off device can be assembled in a simple manner. In this case, it is possible for the shut-off element to be slipped onto the component which forms the inner channel. This results in an overall very simple installation. Particularly when the component that forms the inner channel is a pressed-in pipe, the distribution device can be assembled in a simple manner by first pressing the pipe into the main channel and then inserting the shut-off element into the main channel at the same time and attached to the tube.

The shut-off element can have a housing which is arranged within the main channel and is first flowed through by the fluid stream entering the inner channel from the main channel before the fluid stream enters the inner channel. In other words, the fluid stream flows out of the main channel through the housing of the obturator into the inner channel. This encapsulation of the shut-off element in its own housing enables it to be handled easily, for example during assembly, particularly when assembled by plugging it into the main channel in the sense of the above description.

The shut-off element can have a shut-off element for shutting off the fluid flow entering the inner passage from the main channel, which shut-off element moves parallel to the main direction of extent of the main passage to shut off the fluid flow. Such a design makes it possible to implement the shut-off element in an elongated construction, so that the shut-off element can be arranged inside the main channel.

The shut-off element can be designed in such a way that the shut-off element is acted upon by the pressure of the fluid with forces acting in opposite directions in both directions of movement of the shut-off element. In this way it is possible, in particular, to design the shut-off element to be pressure-balanced. In other words, this means that the actuating forces are in particular independent of the pressure of the fluid and the position of the shut-off element along its direction of movement.

The shut-off element can in particular be a solenoid valve. A solenoid valve offers the advantage of being able to be controlled in a simple and direct manner by a control device due to its direct electrical actuation. In this way it is possible, for example, for a control device which causes cylinder deactivation to simultaneously deactivate the piston of the deactivated cylinder or the pistons of the deactivated cylinders. Compared to pressure-controlled valves, solenoid valves also offer the advantage that the actuation state of the valve is independent of the fluid pressure. This makes it possible, for example, to realize load states of an internal combustion engine that are associated with higher oil pressures without the shut-off element being actuated automatically as a result.

Fig. 1

eine Schnittdarstellung einer beispielhaften Verteileinrichtung,

Fig. 2

eine vergrößerte Schnittdarstellung des Absperrorgans der beispielhaften Verteileinrichtung aus Fig. 1 im geöffneten Zustand,

Fig. 3

eine der Figur 2 entsprechende Darstellung des Absperrorgans im geschlossenen Zustand.

Further practical embodiments of the invention are described below in connection with the drawings. Show it:

1

a sectional view of an exemplary distribution device,

2

an enlarged sectional view of the shut-off element of the exemplary distribution device 1 in the open state,

3

one of the figure 2 corresponding representation of the shut-off device in the closed state.

The distribution device 10 shown as an example in the figures has a main channel 12 . As illustrated, this can have a circular cross section and extend along a main direction of extent X. The distributor device 10 also has a plurality of outlet channels branched off from the main channel 12 . In the example shown, these are the outlet channels 14, 16, 18, 20, 22 and 24. The distribution device 10 can be, for example, an oil gallery of a cylinder crankcase. The outlet channels 14, 16, 18, 20, 22, 24 shown in the example shown can in particular be assigned to different elements of an internal combustion engine to be lubricated and/or cooled and supply them with the fluid, which can be oil, for example . For example, the exhaust port 14 may supply the cylinder head, the exhaust port 18 a bearing, while the individual exhaust ports 16, 20, 22 and 24 are associated with individual piston cooling nozzles for cooling the pistons of the cylinders of the engine. For example, each of the outlet channels 16, 20, 22 and 24 can be associated with a piston of a cylinder of a four-cylinder engine.

In the example shown, an inner channel 26 is arranged within the main channel 12 . This inner passage 26 is adapted to direct fluid entering the inner passage 26 to at least one of the exit passages, such as exit passages 20 and 22 as shown. The distribution device 10 also has a shut-off element 28 for shutting off a fluid flow entering the main channel 12 into the inner channel 26 .

As in the example shown, the distribution device 10 can be designed in such a way that the fluid flow entering the inner channel 26 from the main channel 12 first washes around the inner channel 26 when passing through the main channel 12 . As in the example shown, this can be made possible in that the inner channel 26 is formed by a tube whose external dimensions, or rather its external diameter, is smaller than the dimensions of the main channel 12, in particular than its diameter. The arrangement of the inner channel 26 at a distance from the wall of the main channel 12 can be made possible, as in the example shown, by fastening the inner channel 26 in the main channel 12 by means of suitable spacer elements 30 . The embodiment shown in the figures shows an inner channel 26 which can be pressed into the main channel 12 in a simple manner. The inner channel 26 can have branches 31 . In this case, the inner duct 26 may be positioned in the main duct 12 such that the branches 31 are positioned at locations where the exit ducts to be shut off by the obturator 28 branch off from the main duct 12 . In the example shown, these are the outlet channels 20 and 22.

As in the example shown, the shut-off device 28 can be inserted into the main channel 12 . The shut-off element 28 can be arranged at least partially within the main channel 12, as in the example shown. This makes it possible for the fluid which penetrates from the main channel 12 into the inner channel 26 to first penetrate into a housing 32 of the shut-off element 28 . For this purpose, the housing 32 can have openings 34 which allow the fluid to penetrate into the housing 32 .

The shut-off element 28 can have a shut-off element 36, as shown by way of example. As shown in the figures, the obturator 36 can move along the direction X to shut off the flow of fluid coming from the main channel 12 through the housing 32 of the obturator 28 into the inner channel 26 . This process is in the Figures 2 and 3 shown. In figure 2 the fluid can flow through the openings 34 into the inner channel 26 . In figure 3 the flow path is interrupted by the shut-off element 36 .

The shut-off element 28 can be plugged onto the inner channel 26 as shown in the example. For this purpose, shut-off element 28 and/or inner channel 26 can have suitable end regions 38, 40. These can have insertion bevels, for example, as shown, in order to make it easier for the shut-off element 28 and the inner channel 26 to be plugged together.

It can be advantageous that, for example when the distributor device 10 is used in a method for operating an internal combustion engine as described above, there does not have to be a perfect seal between the shut-off element 28 and the inner channel 26 and between the branches 31 and the wall of the main channel 12 . It is sufficient if the majority of the fluid flow to be shut off is interrupted, minimal leaks at the sealing points will not lead to a cooling effect with such use, which would negate the effect of shutting off the fluid flow with regard to piston cooling.

Accordingly, the shut-off element 28 can have a main channel 12 seal. This is realized by an O-ring 42 in the example shown. In this way, a simple seal between the obturator 28 and the inner channel 26 can be achieved. The shut-off element 28 can be fastened in its intended position, for example with a detachable fastening element such as a screw. In this way, the shut-off element 28 can be removed and installed in a simple manner, for example for repair and/or maintenance purposes.

The features of the invention disclosed in the present description, in the drawings and in the claims can be essential both individually and in any combination for the realization of the invention in its various embodiments. The invention can be varied within the scope of the claims and taking into account the knowledge of the person skilled in the art.

Reference List

10

distribution facility

12

main channel

14

exit channel

16

exit channel

18

exit channel

20

exit channel

22

exit channel

24

exit channel

26

inner canal

28

shut-off device

30

spacer element

31

junctions

32

housing

34

openings

36

shut-off element

38

end area

40

end area

42

o ring

X

direction

Claims (10)

Distribution device (10) for distributing fluid streams, having a main channel (12) and a plurality of outlet channels (14, 16, 18, 20, 22, 24) branching off from the main channel (12), the distribution device (10) being designed to to distribute a fluid flow entering the main channel (12) to the outlet channels (14, 16, 18, 20, 22, 24), characterized in that
that an inner channel (26) is arranged within the main channel (12), the inner channel (26) being designed to conduct fluid penetrating the inner channel (26) to at least one of the outlet channels (20) and the distribution device (10) has a shut-off device (28) for shutting off a fluid flow entering from the main channel (12) into the inner channel (26). Distribution device (10) according to Claim 1, characterized in that the distribution device (10) is designed in such a way that the fluid flow entering the inner channel (26) from the main channel (12) when passing through the main channel (12) penetrates the inner channel (26 ) initially washed around. Distribution device (10) according to one of the preceding claims, characterized in that the inner channel (26) is formed by a pipe pressed into the main channel (12). Distribution device (10) according to one of the preceding claims, characterized in that the main channel (12) is formed by a cast component. Distribution device (10) according to one of the preceding claims, characterized in that the shut-off element (28) is inserted into the main channel (12), in particular the shut-off element (28) being slipped onto the pressed-in pipe. Distribution device (10) according to one of the preceding claims, characterized in that the shut-off element (28) has a housing (32) which is arranged inside the main duct (12) and from which the main duct (12) flows into the inner duct (26 ) incoming fluid stream from the main channel (12) is first flowed through before the fluid stream enters the inner channel (26). Distribution device (10) according to one of the preceding claims, characterized in that the shut-off element (28) has a shut-off element (36) for shutting off the fluid flow entering the main duct (12) into the inner duct (26), which flows to the Shut off the fluid flow parallel to the main direction of extension (X) of the main channel (12) moves. Distribution device (10) according to one of the preceding claims, characterized in that the shut-off element (36) is designed in such a way that the shut-off element (28) is acted upon by the pressure of the fluid with forces acting in opposite directions in both directions of movement of the shut-off element (36). Distribution device (10) according to one of the preceding claims, characterized in that the shut-off element (28) is a solenoid valve. Method for operating an internal combustion engine, in particular by means of a distribution device (10) according to one of the preceding claims, characterized in that a flow of fluid directed to a piston to be cooled is interrupted by means of a shut-off element (28) when the cylinder to which this piston belongs is not fired due to cylinder deactivation, while at least the piston of another cylinder being fired continues to be cooled by means of a fluid flow diverted from the interrupted fluid flow.

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