WO2016177505A1

WO2016177505A1 - Oil circuit for an internal combustion engine

Info

Publication number: WO2016177505A1
Application number: PCT/EP2016/056097
Authority: WO
Inventors: Björn Kramer; Michael Lüer; Serhat GUSINALI; Tobias DOLTZE; Tobias HÖRNLEIN; Thomas Küppers
Original assignee: Volkswagen Aktiengesellschaft
Priority date: 2015-05-04
Filing date: 2016-03-21
Publication date: 2016-11-10
Also published as: EP3292283A1; DE102015208205A1

Abstract

The invention relates to an oil circuit (1) for an internal combustion engine (9), comprising at least one oil pump (5) arranged upstream of a sump (S), and one oil line (3) which is associated with said oil pump (5) and has, in front of said oil pump (5) in respect of the oil pump (5) intake direction, at least one non-return stop (2) that prevents the return flow of the oil partially or fully back into the sump (S).

Description

description

Oil circuit of an internal combustion engine

The invention relates to an oil circuit of an internal combustion engine, which has at least one, arranged upstream of an oil sump, oil pump and an oil pump associated with the oil line.

State of the art

It is from DE 101 10 382 A1 an oil circuit for an internal combustion engine with a

Oil pump, which is connected on the suction side via an oil line to the sump and downstream of a centrifuge and upstream of an oil filter has a return valve, known. The return check valve is located either in front of the oil filter or in front of an oil cooler.

Furthermore, from DE 103 16 340 A1 an oil circuit is known, in which a main oil line has at least one check valve, which is arranged with respect to the flow direction after a shut-off valve.

When starting an oil pump, especially after the start of the engine, is in the oil pump air and the oil must be sucked over a long distance from the sump, so first a very lean mixture or even air is sucked in, with the result that idle noise arise. This problem is particularly disturbing in hybrid vehicles, since they can be operated initially purely electrically before the internal combustion engine starts. The resulting cold start or idle noise during electrical operation of the vehicle are tolerated by the customer only conditionally.

task

The invention has the object of providing an oil circuit in such a way that occurring at the start of an internal combustion engine noises that arise during the suction of the oil from the sump, reduced or even extinguished. The object is achieved in that an oil circuit of an internal combustion engine with at least one oil pump and at least the oil pump and the sump connecting oil line is arranged such that the oil line means, in particular a backstop suction side with respect to the

Flow direction before the oil pump and after the sump, which prevents at least parts of the reflux of the oil downstream of the oil pump.

This ensures that the oil pump is not completely out of oil and thus a resulting in the oil line negative pressure during suction of the oil is significantly lower. The increased noise caused by the compression of the air-oil mixture are significantly better damped by the higher proportion of oil within the air-oil mixture.

For this purpose, it is advantageous that the device is designed such that the

When the oil pump is actuated, the backstop opens via the resulting negative pressure and allows the oil to pass unhindered and, as soon as the oil pump is switched off, locks in such a way that at least parts of the oil are prevented from flowing back into the sump. The device can be placed at any point between the oil pump and the sump.

In a preferred embodiment, the backstop is designed as a non-return valve, in particular as a check valve. This represents a cost effective

Execution dar.

A further embodiment provides that the backstop is designed without a spring preload. By eliminating the spring preload, the flow resistance is reduced and the number of components is reduced to a minimum.

Another embodiment of the backstop is a piston variant, which opens by the negative pressure upon actuation of the oil pump against his (the piston) dead weight or against a spring and automatically closes by its own weight and the weight of the oil after switching off the oil pump. An advantageous development provides that the backstop is adjustable or controllable. Overall, the use of a setting or control device allows optimum control of the oil volume flow in general or within the oil line.

A further embodiment provides that the backstop is designed such that the oil line provides a double reversal of the direction of the oil, which

is designed in particular as a siphon. In such a formed turning point of the oil line remain parts of the oil. The oil must therefore be sucked in over a smaller distance to be overcome than if it were sucked directly from the sump. The smaller distance here causes the resulting cold start noise is shifted in time so that it is superimposed by a starter noise of the internal combustion engine.

An inexpensive embodiment is the formation of the backstop as at least two mutually durable in any position, rotatable perforated discs. The perforated discs are rotated against each other so that in at least one position A corresponding holes are exactly on top of each other and so allow the maximum flow and such that in at least one position B, the holes do not exactly overlap so that the flow is blocked.

A further embodiment provides that projections are formed in the interior of the oil line, which are designed in particular as pockets. The oil remains partially stuck in the pockets and can also be sucked in over a smaller distance to be overcome, so that in the oil pump directly a richer, so having a higher oil content, air-oil mixture is sucked.

embodiments

Further details of the invention are illustrated in the following description of exemplary embodiments and the associated figures.

Showing: Fig. 1 is a schematic representation of an oil circuit 1 according to the invention

1 a is a schematic sectional view of the oil line 3 of FIG. 1 in a

preferred embodiment of the backstop 2 as a ball valve in each case an open and a closed position

Fig. 2 is a schematic sectional view of the oil line 3 of FIG. 1 in a

Second embodiment of the backstop 2

3 shows a section through a third embodiment of the backstop second

within the oil line 3 according to FIG. 1, which has projections 7 in its interior

Fig. 4 is a schematic representation of the oil line 3, which is a double

Direction reversal has

Fig. 5 shows a fourth embodiment of the backstop 2 as a piston variant

Fig. 6 shows a fifth embodiment of the backstop 2 as a flap

Fig. 7 shows a sixth embodiment of the backstop 2 by means of

perforated discs

The oil circuit 1 according to FIG. 1 has an oil line 3, which connects via a means, in particular a backstop 2, a sump S with an oil pump 5. The

Backstop 2 is used to prevent a backflow of at least parts of the oil in the sump S. The route that connects the oil line 3 between the oil pump 5 and the sump S, is referred to as suction. The oil pump 5 must suck in the oil from the sump S via the suction path. Starting from the sump S, the backstop 2 at a distance d and then the oil pump 5 is provided with reference to the flow direction first. The distance d is within the suction section, between the sump S and the backstop 2, freely selectable. The oil pump 5 is connected to the internal combustion engine 9 via an oil line 17 and the oil circuit 1 is closed via a further oil line 19 to the sump S.

The oil line 3 of FIG. 1 a is formed such that within the oil line 3, the backstop 2 is located, which is designed as a ball valve 2. The ball valve 2 has a ball 23. The ball 23 is by means of a cage 21 in a seat 25, in particular a valve seat, guided. In addition, the cage 21 prevents the ball 23 from dodging.

The backstop 2 according to FIG. 1a works as follows:

When starting an oil pump 5, an oil flow 15 is sucked by the oil pump 5. Within the oil line 3 creates a negative pressure, which is both the oil content which is located above the backstop 2, as well as oil from the sump S, and at the same time the backstop 2 is actuated such that the ball 23 along the cage 21 from the valve seat 25th , according to pos. A, lifts off and releases a flow 15 to the oil pump 5. After switching off the oil pump 5, the negative pressure drops and the ball 23 is pressed by the weight g of the oil and its own weight back into its valve seat 25, according to Pos. B, so that a residue 12 of the oil, with respect to the suction direction of the oil pump 5, after the backstop 2 remains.

2, the backstop 2, which is designed as a check valve and has a closure 1 1 is located within the oil line 3. The closure 1 1 is held by a spring element 13. The oil flow 15 is upstream in

Suction of the oil pump 5 shown. In position A, the backstop 2 is opened and the spring element 13 is under tension. In position B this is

Check valve 2 closed and the spring element 13 is relaxed.

The embodiment of Figure 2 operates as follows:

When starting the oil pump 5, the oil flow 15 is sucked by the oil pump 5.

Within the oil line 3 creates a negative pressure, which is both the oil content which is located above the backstop 2, as well as oil from the sump S, and at the same time the backstop 2 is actuated such that the closure 1 1 from a closed position B in an open Position A against a force of

Spring element 13 is pulled. The oil flow 15 flows from the sump S through the spring element 13 on the closure 1 1 over to the oil pump. 5

When switching off the oil pump 5, the negative pressure in the oil line 3 drops. The oil flow 15 is pulled back into the sump S by its weight g. At the same time closed by the absence of negative pressure, by the weight g of the oil flow 15 and by the weight of the closure 1 1, the closure 1 1, the compound between the oil pump 5 and the sump S. The residue 12 of the oil is after closing the shutter 1 1 still in the intake of the oil pump 5 before the backstop 2 within the oil line. 3

Fig. 3 shows a section through the oil line 3 upstream of the sump S and downstream of the oil pump 5 of another embodiment, wherein the oil line 3 has projections 7 in the form of pockets. Preferably, the oil line 3 in this

Embodiment have an oil reservoir 8.

The residue 12 of the oil remains after switching off the oil pump 5 as shown in FIG. 3 inside the pockets 7 and hang in the oil tank 8 and can be sucked at restarting the oil pump 5 first and thus shifts the idle noise of the oil pump 5 forward in time.

According to Fig. 4, the backstop 2 is designed as a double reversal of direction of the oil within the oil line 3 as a siphon.

The double reversal of direction of the oil within the oil line 3 can either serve as a single means for the backstop 2, or achieve a better effect in combination with other embodiments. After switching off the oil pump 5, the residue 12 of the oil, with respect to the suction direction of the oil pump 5 after the backstop 2 remains.

In a further embodiment according to FIG. 5, the backstop 2 in the oil line 3 is designed as a piston variant.

For the piston variant, a reciprocating piston 27, which is guided in a piston guide 31, disposed within the oil line 3 such that it is lifted by a negative pressure or an additional actuator unit of a piston seat 29, according to Pos. A, upon actuation of the oil pump 5, so the flow of oil 15 can pass the piston 27. When switching off the oil pump 5, the piston 27 is guided by the weight g of the oil and its own weight back into its piston seat 29 so that it closes the oil line 3 according Pos. B sealing and only a portion of the oil can flow back into the sump S and a Residue 12, with respect to the suction direction of the oil pump, remains after the backstop. Fig. 6 shows a section through the oil line 3 upstream of the sump S and downstream of the oil pump 5 of another embodiment, which has a flap 33 which is pivotally mounted on a pin 34 has. The flap 33 is designed in a preferred form as a throttle.

When switching on the oil pump 5, the flap 33 by means of the resulting

Vacuum is rotated about the bearing pin 34 so that the flow 15 is enabled, as shown in pos. After switching off the oil pump 5, the flap 33 rotates in Pos. B and closes the flow possibility, so that a residue 12, with respect to the suction direction of the oil pump 5, within the oil line 3 remains.

According to Fig. 7, the backstop is designed as mutually rotatable perforated discs 35. The perforated discs 35 are mounted one above the other and can be rotated at least so far that you release according to Pos. A the flow 15, or according to Pos. B block the flow 15 and after blocking a residue 12, with respect to the suction direction of the oil pump 5, after the

Backstop 2 in the oil line 3 remains.

In one embodiment, not shown, the backstop 2 may be adjustable and / or controllable.

LIST OF REFERENCE NUMBERS

1 oil circuit

Backstop; ball valve

oil line

oil pump

Tab, pocket

oilcontainer

Internal combustion engine

1 1 closure

12 residue

13 spring element

15 oil flow, flow

17 oil line

19 oil line

21 cage

23 ball

25 seat, valve seat

27 reciprocating piston

29 piston seat

31 piston guide

33 flap

34 pin, bearing pin

35 perforated disc

S swamp

d Distance between sump and backstop 2 g Weight, weight

suction line

Claims

claims

1. oil circuit (1) of an internal combustion engine (9) with at least one oil pump (5) and at least one oil pump (5) and a sump (S) connecting the oil line (3), characterized in that the oil line (3) with respect the suction direction of the oil pump (5) before the oil pump (5) at least one means (2), in particular a backstop (2), which prevents the return flow of the oil proportionately or completely into the sump (S).

Second oil circuit (1) according to claim 1, characterized in that the means (2) as

Return valve, in particular as a check valve, is executed.

3. oil circuit (1) according to claim 1 or 2, characterized in that the means (2) is designed without a spring preload.

4. oil circuit (1) according to one of the preceding claims, characterized in that the means (2) is designed as a piston variant (27).

5. oil circuit (1) according to any one of the preceding claims, characterized in that the means (2) is adjustable or controllable or adjustable and controllable.

6. oil circuit (1) according to any one of the preceding claims, characterized in that the means (2) is designed such that the oil flow (15) a two-time

Direction reversal provides.

7. oil circuit (1) according to one of the preceding claims, characterized in that the means (2) as at least two mutually rotatable perforated discs (35) is executed.

8. oil circuit (1) of an internal combustion engine (9) according to any one of the preceding claims, characterized in that the means (2) as projections (7) in the interior of the oil line (3) is formed.

9. oil circuit (1) of an internal combustion engine (9) according to any one of the preceding claims, characterized in that the oil circuit (1) is arranged within a hybrid vehicle.

10. Oil circuit (1) of an internal combustion engine (9) according to any one of the preceding claims, characterized in that the oil circuit (1) has a return line (19).

1 1. internal combustion engine, characterized in that the internal combustion engine has an oil circuit (1) according to one of the preceding claims.