DE3039774A1 - IC engine inlet duct - contains swivelable vane to control inlet whirl on entry into cylinder e.g. as function of engine parameters - Google Patents

Abstract

The i.c. engine has an inlet duct (4) leading to an inlet valve (5) and containing a guide vane (8) to produce a rotary flow on entry into the cylinder. This vane is movable between a first position to direct the flow eccentrically towards the inlet valve and a second position to produce central flow with little whirl. The vane may be swivelable about apivot (9) arranged parallel to the valve axis on a side wall of the duct (4,6). Its position may adjust under the action of the flow through the duct, e.g. against a spring (11), or in response to operational engine parameters.

Description

SHARED COMPANY

5180 Wolfsturg

- 3 -

Our reference: K 2970
17O2pt-we-jä

Internal combustion engine

The invention "relates to an internal combustion engine according to the preamble of claim 1.

As is known, the combustion process in internal combustion engines, and especially in direct injection diesel engines, but also in Otto engines, by generating a so-called intake swirl be improved. In this case, the air flowing in through the inlet channel is made by appropriate shaping of the inlet channel or by Use of swirl-generating internals in the inlet channel communicated a strong swirl, which leads to a defined air movement at high speed leads in the combustion chamber. The swirl generated in the air flow is essentially determined by the geometric relationships in the duct and determined by the respective engine speed. While it is now expedient to ar with as high a twist as possible at low speeds working, there is a strong throttling at higher speeds and correspondingly high air throughputs, which leads to considerable loss of efficiency leads and thus limits the engine power. At the same time it results that the inlet swirl at higher throughputs in general does not need to be particularly large, as one with a slow turning speed A large amount of air flowing in can have the same angular momentum as one with a high rotational speed Air volume.

Chairman of the Board: Toni SOimücfcer, Chairman - Ka'l-Heinz Brian-, · Prpr. Dr. tee * '·, l "··, · noin ■ D. ·: *' Pe: e ^r Frerit

of the Supervisory Board: Dr.jur. Wolfgang R.Hebbel ■ Günter Hariwicn Ho'St Munzner · Dr.rei.poi.We'ne'P.Ecnmmt · P'oi.Dr. tm. pol. Fneoric'i Tfioiiee »5-s Eirr.biu". Sitr of the company: Wolfsburg District Court Wollsburg HRB 215

For this reason, in a known internal combustion engine (DE-OS 28 05 555), the inlet channel is formed by two channels, from one as a swirl channel and the other as a swirl-free channel are designed, which are acted upon in opposite directions with increasing speed in the sense of a reduction in the twist. Here, however the arrangement of two parallel inlet ducts is required, which is not easy given the known tight space conditions in internal combustion engines Difficulties can be met. The object on which the present invention is based is therefore to develop an internal combustion engine of the type mentioned at the outset to create a favorable, while avoiding the disadvantages of the aforementioned known internal combustion engine Control of the inlet swirl allows so that at low speeds a required for an optimal mixture preparation is sufficient high air inlet swirl is provided, on the other hand at higher speeds the swirl leading to losses is reduced ^.

The solution to this problem results from the characterizing part of the patent claim 1.

After that, the swirl-generating one formed by a flow guide means is Means used to control the swirl by adjustment. According to further training of the invention should the flow guide means expediently by one on one Side wall 'of the inlet channel held, protruding into the inlet channel Be formed flap which is adjustable about an axis running parallel to the valve axis. The actuation of this flap can be automatic take place by the back pressure of the flow passing through the inlet channel, the flap as a swivel flap or as a spring-tongue-like flap Flap can be formed. However, it is also possible to adjust the swivel flap as a function of the operating state of the internal combustion engine to adjust characterizing sizes.

In the drawing, an embodiment of the invention is shown, daa is explained in more detail below. The drawing shows in schemati books Display white in

Figure 1 shows a section through a cylinder of a reciprocating internal combustion engine along the axis of the inlet duct and

FIG. 2 shows a section through the cylinder head according to FIG Section lines II-II according to FIG. 1.

In the drawing, 1 is the cylinder of the internal combustion engine, and 2 a reciprocating piston oscillating therein and indicated by 3 the cylinder head, in which one through an inlet valve 5 in a conventional manner controlled inlet channel 4 is incorporated. Everyone's inlet ducts Cylinders of the internal combustion engine are combined to form an intake pipe 6 in which a conventional throttle valve 7 is pivotably mounted is. ·

Vie from Figures 1 and 2 can be further seen, is in the area of At the entrance of the inlet channel 4, a flap 8 is arranged on a side wall of the inlet channel is held adjustable about an axis running parallel to the valve axis. The adjustment of this flap 8 takes place between a first in FIG. 2 with extended lines. Lines indicated End position in which the flap, protruding into the inlet channel, causes an eccentric flow against the inlet valve 5. In the second, with End position indicated by broken lines, the flap 8 releases the entire inlet channel, so that the flowing in the direction of the arrow Air is applied to the inlet valve 5 essentially centrally. While so if there is a strong inlet swirl in the first end position of the flap, this swirl becomes greater the closer you get to the second end position significantly reduced, so that Bich finally has a nearly Swirl-free inlet flow results.

In the embodiment shown in the drawing, the flap has a essentially vertical pivot axis 9 held in the suction line 6 with an actuating arm 10 on which a return spring attacks. The actuation of this flap 8 can now be carried out automatically by the dynamic pressure exerted on the flap and penetrating the inlet channel Flow or by the negative pressure prevailing in the flow shadow of the flap, that is to say essentially take place automatically. The operation However, it could also be force-controlled depending on the operating status the internal combustion engine characterizing variables, such as the power or the speed, take place. Here too would be an actuating mechanism on the pivot lever 10 Attack against the return spring 11, so that at low

Air flows through the flap essentially in the first end position and with higher air flow rates increasingly towards the second End position is adjusted.

Instead of such a swivel flap, however, a resilient one could also be used be provided elastically adjustable about an axis arranged parallel to the valve axis. This tongue-like flap would then be actuated automatically by the back pressure of the flow and adjust themselves in the aforementioned sense.

To the effect intended by the invention of the formation of a swirl To achieve flow on the inlet channel 5, the flap must reach essentially up to close to the inlet valve 5 and in their vertical dimensions essentially correspond to that of the inlet channel 4, which is expediently at least in the pivoting range of the Flap should have a rectangular cross-section.

Incidentally, in FIG. 2 of the drawing, 13 is also indicated by a Outlet valve 12 controlled outlet channel indicated.

Claims (6)

AKTIENGESELLSCHAFT 3180 Wolfsburg Our reference: K 2970
17O2pt-we-jä EXPECTATIONS Internal combustion engine with an intake port assigned to each cylinder, which has means for generating a swirl upstream of an inlet valve opening into a combustion chamber, characterized in that that the swirl-generating means are formed by flow guide means (8) which between a first, a substantially eccentric, swirled flow onto the inlet valve (5) and a second, essentially central, low-swirl flow onto the Inlet valve causing position are adjustable. 2. Internal combustion engine according to claim 1, characterized in that the Flow guide means through a flap which is held on a side wall of the inlet channel (4 »6) and protrudes into the inlet channel (8) are formed, which is adjustable about an axis running parallel to the axis of the inlet valve (5). 3. Internal combustion engine according to claim 2, characterized in that the The flap (8) is automatically adjustable by the dynamic pressure of the flow passing through the inlet channel (4). Chairman Vontend: Toni SCimücfcer, Chairman - Karl-Heinz Briam · Prcl. Ui. leO "-E'nül hale - Di j-jr Pete 'Frer of the supervisory board : Dr.jur Wollgong R. Habbel · Günter Har'wicn · Horsl Munzner · Dr.rerpol.Wiv'ner P.Stivn.di · Pfoi.Di.rer.poi.F'-ed ' c · - Thorn * . ia-ί Birr-os ·· .- Seat of Gcullschail: Wolfsburg District Court Wollsburg HRB 21 4 · internal combustion engine according to one of claims 1-3 »characterized j that the flap (8) is held pivotable about the axis against the force of a return spring (11). 5. Internal combustion engine according to claims 1, 2 and 4 ι characterized in that the - ^ flap (8) can be actuated depending on the operating state of the internal combustion engine characterizing variables. 6. Internal combustion engine according to claims 1-3, characterized in that that the flap is held resiliently adjustable about the axis.