DE1803593A1 - Carburettor internal combustion engine for motor vehicles - Google Patents

Description

YOLKSVAGEKWERK Aktiengesellschaft

Wolfsburg October 10, 1968

Our reference: K 734 1 OÜ O O 9

1700-Dr.W / Su

description

Carburettor internal combustion engine for motor vehicles

The invention relates to a carburetor internal combustion engine for motor vehicles.

In multi-cylinder internal combustion engines, the mixture preparation can be based on a carburetor that is common to several cylinders on the single cylinder - be uneven. It is therefore known to assign each cylinder its own carburetor and the carburetor with the assigned throttle valve in the immediate vicinity to arrange the inlet valves. However, such a measure is out of the question for utility vehicles for reasons of cost .

According to the invention, therefore, in an internal combustion engine, a relatively simple carburetor (only for the main system) is available for all Cylinder proposed together. The idle and part load systems - including the throttle valve - are placed in the immediate vicinity of the intake valves especially for each cylinder.

The advantages of the invention are shown below for a four-cylinder boxer engine explained.

As is illustrated in the attached schematic top view of FIG. 1, a boxer engine has the firing sequence 1, 4 » 3 $ 2. This firing sequence is the only possible firing sequence for a boxer engine

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cylinders 4 and 2 have a richer mixture than cylinder 1 • and 3. The phases between the closing of the inlet valves "1 or 3 up to the closing of the inlet valves 2 and 4 are significant longer (540 ° CA) than the phases between the closing of the inlet valves 2 or 4 and the closing of the inlet valves 1 or 3 (I8O KW). As a result, there can be in the suction line and deposit different amounts of fuel in front of the valve, evaporate there and cylinders 2 and 4 sucking in after 540 KW in the firing order receive the same with the Fuel vapors enriched mixture »This separation of the "rich" and "lean" cylinder groups determined by the firing order are independent of engine speed and load conditions. With a higher speed, the differences become smaller, since there is less time for vaporizing, but precisely the speed ranges and load conditions in which exhaust emission tests to be made, namely the idle range and the range of low partial loads, are of this undesirable different mixture formation particularly affected.

The measures according to the invention can, despite different Mixture preparation all cylinders can be set individually (idle and part load). The cylinders can also be connected to each other can be adjusted more evenly.

During the overlap phase when idling, with low partial loads and especially with Sohubvorgangs®n, there is a large bridge difference between the suction channel and the exhaust line. Since the speed is also very low under these loads (except for high thrust), the pressure difference can largely compensate for the condition between the two channels via the combustion chamber because of the relatively long duration. Here flow hall) · * and fully burned Ver ~ combustion products into the suction line and kSnnon penetrate to the throttle valve (Bin another ford wrestling is fc vM möglioh since before the throttle about atmospheric ZuBtSnSo ₉ similar to the exhaust pipe, prevail) ® Bieee hardly

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capable combustion product after closing the Exhaust valve "diluted with only a little fresh mixture during the suction stroke sucked into the cylinder. The residual gas portion of this process will therefore be particularly large and so will the combustion heavy. According to the invention, the residual gas content is small held. Another part of the gate of the invention is that the throttle valve moves closer to the valve and thus decreases the line volume between the inlet valve and the throttle valve. This ensures that in the exhaust gas test important, but also at the same time the most unfavorable areas for combustion (high negative pressure in the intake manifold) only the minimal amount of exhaust gases is sucked back into the cylinder. The high dilution of fresh gases with combustion products is thus reduced and the combustion is improved, Greener exhaust emissions are the result.

In Figures 2 and 3 is a system according to the invention for a double carburetor position illustrated schematically in two views. Double suction pipes lead from the double carburetor 10 11 or 12 to the idling systems 15 - 16 arranged in the vicinity of the cylinder linstrangsaugröhre used, which is near the cylinder with trouser-shaped split suction connections are provided. The idle system is the fuel from the carburetor 10 through one each special line 17 or 18 (indicated by dashed lines in Figure 3) supplied. Idle systems 13-16 have one simple structure. In Fig. 4 is an idle system with the Throttle valve 21, the idle air corrector nozzle 22, the bores 25, 24 for the idle mixture nozzle and the idle - Volume control screw (or nozzle) and with the for the Partial drainage necessary bypasses shown in section. For neighboring cylinders, both systems can be arranged in a common housing and both throttle valves can be attached to a common shaft 25.

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Claims (2)

VOLKSWAGEIiWERK Aktiengesellschaft Wolfsburg . the IO.IO.I968 Our reference: K 734
1700-Dr.W / Su Expectations Multi-cylinder internal combustion engine, in particular a boxer engine, for motor vehicles, with one for several cylinders common carburetor, characterized in that the idle and part-load systems (13-16) with the throttle valves (21) are arranged in the immediate vicinity of the inlet valves. 2. Apparatus according to claim 1, characterized in that two adjacent cylinders in a common housing (20) individual idle and part-load systems as well as individual, but on a common shaft (25) fixed and synchronous moving throttle valve (2l) are assigned. 0098 ^ 5/0663