History - Carburetor 1
What you can see here, copper-coloured to the left of the actual cylinder, is the float carburettor designed by Maybach in 1886. Before that, Daimler and Maybach still powered their engines with gas to save time. The fuel
comes from the top centre, but then fills the relatively large tank from below. Through the glow tube heater and/or the exhaust pipe preheated air flows from the right . Fresh air, which comes into intensive contact with the fuel
at many points in the carburettor, even a constant quantity of petrol in a funnel of the float.
The result is air with a higher fuel content on the left enriching fresh air coming from above regulated by a mixing valve. The now finished air-fuel mixture goes through the pipe right to the Intake valve of the combustion
engine. Remarkable is the size of the first carburetors. Below is a much larger one, which Otto used on his four stroke engine. Just like his engine in no normal car the carburettor would not have fit, let alone the carburetor.
It is called a 'surface carburetor'. The huge cylinder is actually just a petrol tank with surrounding warm cooling water. There is an indicator of the filling, which can be refilled from time to time through a tank with hand pump.
The air supplied to the carburetor is regulated and flows to the bottom of the tank, forcing the air to flow through the entire fuel supply. Before this mixture is sent to the internal combustion engine, it must pass through a pot
filled with gravel, which causes too large drops to be returned.
No, petrol engines were only in demand to a very small extent at the Deutz gas engine factory. Not only did they need a carburetor, but the ignition was much more complicated than at operatig with gas. Now you will probably
ask yourself where the name 'Vergaser' (gasifier) comes from, if at most a certain preheating plays a role here, but under no circumstances gaseous petrol is used. It comes from the knowledge of the time and the simplicity
of operation with gas. So in theory, it was assumed that petrol had to be gaseous, then it could be treated in the same way as luminous gas.
If you look at burning petrol or, better, Diesel fuel, you will notice that only the gaseous components of the respective substances burn, the flame practically on top of the liquid level. For a long time, attempts were also made
to 'gasify' the petroleum already used for steam engines and lighting. Even the small liquid level still standing in Daimler and Maybachs workshop today Barrel with the inscription 'Petroleum' (picture above) indicates such
experiments. Alone, it never worked. Petroleum and Diesel fuel only burn when injected into a highly compressed space or blown in with air.
Actually, we should be reporting a lot of experiments here, even by foreign engineers. But since it is always about the same principle, i.e. letting air flow through a petrol mist, we have been working with the two examples of
Otto and Maybach. Especially since the latter actually succeeded in making the groundbreaking invention, which in principle has never changed as long as carburetors have been used. It is simply called 'Spray nozzle
carburettor'. Maybach has carried out many experiments on this, as his entries prove. It is sad for him that his invention is not recognised as a patent in Germany because it is allegedly not innovative enough was, abroad it
You may have guessed it, for the other inventors of components around the combustion engine the way was clear for a copy. But what is it that is actually new? Put simply, it is the creation of negative pressure due to a
constriction in the intake duct, which affects a fuel line ending there. In principle, this is exactly what ensures a relatively constant mixing ratio and almost even more a good mixing the air with fuel. Later, the constriction
became an air funnel, which ensured a more even flow.
This is where the float chamber now comes into its full bloom, because it ensures that the level is always the same, at least in theory. If you consider that such a system in a car is constantly in motion, the only way to get
around this is to align the float chamber forward in the direction of travel. This way the engine gets less fuel when braking and more when accelerating. Conversely, it would make less sense. This carburetor has few
protective measures against very strong lateral forces. In sharp curves, possibly stuttering engine has accompanied this type of carburetor for a long time.
As you have probably already noticed, the air is sucked in from below, which was state of the art for a long time. Why is that? One important reason was probably that overflowing fuel from the carburettor, as far as the fuel that
could not be carried by the air, dripped away downwards and was later processed. Compared to the downdraft carburettor, the ascending flow carburettor has the advantage that too much fuel does not get into the
combustion chamber, wetting the spark plugs there and putting the engine out of operation.