DE1576519A1 - Device for reducing harmful exhaust gas emissions from internal combustion engines - Google Patents

Description

Daimler-Benz Aktiengesellschaft Ilaini 6816/4

Stuttgart - Untertürkiie on 1.9.1966

¹¹ device for reducing harmful exhaust gas emissions from internal combustion engines "

The invention relates to a device for reduction the harmful exhaust gas emissions from internal combustion engines primarily installed in vehicles, in particular from Kraf tfahrzeug-Brennkraftmaschiiien in the idle range, whereby the combustion air in the! door is operated through a throttle valve controlled and the idle air is supplied to the internal combustion engine bypassing this throttle valve.

A device of the above type has already been proposed been, in which the intake air through throttle valve-free individual intake pipes between the cylinders and one in normal operation depending on a throttle valve controlled collecting suction pipe is performed. This older one The proposal is based on a completely different problem. There it is about idling the harmful Influence of air vibrations in the individual intake manifolds to prevent. In contrast, the present invention is a completely different problem the lowest possible GO emissions in the exhaust gases when idling To achieve this, the idle mixture should be set as lean as possible. Such an emaciation will However, a limit is set by the concentricity of the lotor, This limit can be shifted even further in the lean direction through better mixture preparation.

Such a better preparation can be made according to the invention with the devices mentioned at the outset,

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that for a stimulation of the idle air the idle air duct in the immediate vicinity of the exhaust pipe. This can be done by simply laying the pipes accordingly Jüfnah take place. However, the invention is preferred a solution, after which the idle air duct with the exhaust pipe is united into a single casting. It would then be possible for the exhaust line to pass through the idle air duct covers like a coat. Another embodiment provides that the tubular exhaust pipe in its wall Idle air duct is naturally essential as an additional pipe takes smaller diameter.

The device according to the invention achieves a processing which is superior to the usual atomization of the fuel is · This formatting is particularly advantageous as it only extends to the idle area and consequently do not adversely affect the degree of delivery and thus the power output in the partial or full load range can. This effect can be improved even further in internal combustion engines with fuel injection into the intake manifold if, according to a further development of the invention, the exhaust pipe is also used to preheat a limited Zone serves the intake manifold, which is opposite the fuel injector lies. This limited zone can then be used with the fuel jet under an oblique angle if necessary Inject the angle so that the fuel at least partially evaporates. This means that there is also another one in the partial load area Emaciation possible without the power peak being noticeably reduced ^

As mentioned at the beginning, there are other reasons Internal combustion engines, whose intake manifold individually or in groups from a common intake port on the cylinders to lead. jPtir this type of internal combustion engine suggests the invention before «that the exhaust pipe is directly next to the cylinder

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heads under the intake manifold and the idle duct on the lower side of the exhaust pipe along the entire length of the cylinder block next to this or with this is united. This device can then be designed according to a further feature of the invention so that that the idle air duct is connected at one end to the clean air side of the air filter and after passing through it the exhaust pipe runs approximately parallel to itself along the intake manifold and there corresponding openings for the passage of the idle air into the intake manifold. The design of this transition is well known to the skilled person Leave it up · However, it will be particularly useful if all channels and lines are integrated as one Casting are combined so that the transfer openings through holes in the Y / and between the idle air duct and the intake manifold can be formed.

The inventive device can be an effective reduction in harmful exhaust gas emissions in the Y / arm run and Reach the idle range. The device is also structurally very simple. The regulation of the idle air can to:; I in any and be. be done otherwise. The invention prefers a solution according to which in the idle air duct in front of which the Öi'fnun ^ en to the suction nozzle containing stretch a iiegv.lierschraub is arranged.

Details of the hrii-iding are inclined by the .tusi lead see example the drawing, una ^ was shows:

j? ig..1 which he;. "i: idun.; s according device ir. scheme,

"2 and 3 ^ usführungsforiu of the invention (partly) in t Schni and plan view.

Iiach? Ig.1 "vira ei / .er" Hinsprita-3rennkraftmaschine 10 die Combustion air is supplied through the intake port 11, in pairs together ::: -.engefait and to one. Air tube 12

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to lead. The entry into this air collection tube 12 is controlled by a throttle valve 13, which in known \ 7eise can be operated from the accelerator pedal 14 at the same time as the injection pump 15. In front of the throttle valve 13 lies in In a manner known per se, an air filter 16. The injection pump 15 supplies the injection nozzles 17 with fuel which are arranged in the intake port 11. The exhaust gases emerge from the cylinders into the exhaust pipe 18, which leads to the exhaust pipe, which is no longer shown.

From the main air side of the air filter 16 is an idle air duct 19 branched off over the entire length of the cylinder block in the immediate vicinity of the exhaust pipe 18 runs. The idle air is correspondingly in this area heated up. At the end of this preheating section, the idle air duct 19 shows a reversal piece 19a and it runs then back in one piece 19b parallel to itself, openings are provided in this piece 19b - those later is described in more detail in FIG. 2 - through which the empty air can pass into the intake port 11. A regulating screw 20 is provided in front of the pipe section 19b, through which the idle air is regulated can. A duct 21 branches off in front of it and is intended for the warm-up air.

According to Figures 2 and 3, the exhaust pipe 18 runs directly next to the cylinder heads, which are no longer shown exactly, under the intake manifold 11. Both are one unitary casting combined, so that a limited zone 23 of the intake port is heated by the partition 22 will. This zone 23 lies opposite the injection nozzle 24, which directs the fuel jet obliquely onto this wall 22 sprayed in zone 23. The idle air duct 19 is cast into the Y / andung aer exhaust line, so that there too _ute preheating is achieved. The counterpart 19b of the

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Idle air duct is in the connection of the intake manifold poured in, "so that everyone!" hurry to learn uniform Casting are combined, only the reversal 19a or the Connection pieces or end pieces can be used as separate pipe pieces. In the wall 25 between the counterpart 19b and the intake port 11 are openings 26 through which the idle air enters the intake port.

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Claims (1)

Claims : 1. Device for reducing harmful exhaust gas emissions of internal combustion engines primarily installed in vehicles, in particular of motor vehicle racing engines in the idling range, with the combustion air in normal operation controlled by a throttle valve, e and the idle air bypassing this throttle valve of the internal combustion engine is supplied, characterized in that for heating the idle air, the idle air duct (19) immediate .Close to the exhaust pipe (18) runs » 2. Device according to claim 1, characterized in that that the idle air duct with the exhaust pipe ;; u united in a single casting _e 3r device according to claim 1 or 2, characterized in that that the exhaust pipe (18) dew; he the. still for preheating a certain 3one (23) is used by the suction nozzle (11), which is opposite the fuel injection nozzle (24). 4. Device according to one or more of claims 1 to 3, and for an internal combustion engine whose Anaaugstutzen individually or in groups γόη a common Ansaugsami-.elrohr lead to the cylinders, characterized in that the exhaust pipe (13) is directly next to the cylinder heads runs under the intake port (11) and the idle air duct (19) a-uf the lower side of the exhaust pipe (18) runs through the entire length of the cylinder block (11). 5. Apparatus according to claim 4, characterized in that the idle air duct (19) at one end to the clean air side of the air filter (16) is connected i. =. nd after passing through the exhaust line (Ic) has a reversing piece (19a) on v / eist and runs approximately parallel to itself in a counterpart (19b) along the intake port (11) and corresponding ■ Openings (26) for the idle air to pass into the intake manifold (11). Q098O8 / O92S BATH ORIGINAL 6, device according to one or more of the claims 1 to 5 »characterized in that in the idle air duct in front of the counterpart (19b), which the Has openings (26) to the suction nozzle (11), a regulating screw (20) is arranged. 009808/0926