Engines, development, construction and use
Petroleum and gasoline engines, development, construction and use.
A handbook for engineers, students of mechanical engineering, farmers and tradespeople of all kinds.
____
Edited by
G. Lieckfeld, civil engineer
in Hanover.
München und Leipzig.
Druck und Verlag von R. Oldenbourg.
1894.
Foreword.
Now that the design of petroleum and gasoline engines has progressed to the point where these machines can be placed alongside all other engines in terms of safety and cheapness of operation, it will be of interest to those involved to gain an insight into the nature and characteristics of these machines.
The further development of these engines and their use in the various branches of mechanical engineering offer the engineer a new, extensive field of work. For the tradesman and especially for the farmer, they have become a new source of power that could not be imagined to be more independent, cheaper and more convenient.
This document describes the development of petroleum and gasoline engines, describes the machines that have proven themselves in practice, gives advice for new designs, and shows, in particular, through a large number of examples, the extraordinarily wide range of uses that are open to these engines.
Many of the engines and structural parts described are
protected by patents, but it has not been possible to identify the subject of the patent in all cases. Before replicating one or other of the designs shown in the figures, it is therefore advisable to use the patent list and the associated patent descriptions set out in the tenth chapter.
Hanover, October 1894.
G. Lieckfeld.
Fifth chapter
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The petroleum engines.
The efforts to make ordinary petroleum, as used to power petroleum lamps everywhere, also usable for the purpose of generating power, appeared at the same time as the first petrol engines. Already in the third chapter it was mentioned that the inventors of older petrol engines had made attempts to add petroleum to the petrol supply during operation; engines were also built which were started with petrol and, after reaching operating heat, were fed with pure petroleum from another container. However, all of these machines remained experimental objects and did not develop into marketable petroleum engines. The real obstacle to the production of usable petroleum engines was the lack of a suitable ignition device and associated pilot flame. The old flame ignitions, in which "transfer flames" generated in the cavities of slides and valves transferred the ignition temperature to the charge, were not suitable for either gasoline or petroleum engines. The electric ignition, which serves very well in gasoline engines, also proved to be unsuitable, quite apart from the complicated generation of electricity.
It was only from the time when people in wider circles began to concern themselves with glow-element ignitions, following the example of the engineers L. Funk and G. Daimler, and practically usable petroleum heating lamps for the evaporator chambers and glow-elements were invented, that marketable petroleum engines appeared.
The more reliable effect of glow-element ignition in petroleum engines compared to flame ignitions can be easily explained by the nature of the mixture that is burned. It is not as uniform as that used in gas engines, which is formed from two permanent gases, atmospheric air and illuminating gas. Here we are dealing with a mixture of the highly volatile petroleum components that exist as vapor and the less volatile petroleum components that have already turned into mist and the air. In order to ignite such mixtures safely, a larger contact surface is required.
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The path to be taken to use petroleum in engines is clear. Petroleum is less volatile than gasoline; in order to make it suitable for mixing with atmospheric air, it had to be heated intensively to make it evaporate quickly. However, due to the fact that the components of petroleum boil at very different temperatures, only as much petroleum could be used for evaporation from the supply as corresponded to the correct content of the individual charge. The methods that have been used to date to form the charge in the sense indicated can be summarized in two groups:
Firstly, the space intended for the evaporation of the petroleum is separated from the working cylinder by a valve and is heated either by a separate flame or by the waste heat of the ignition tube flame; secondly, the evaporation space is in constant connection with the interior of the cylinder, is constantly heated by a separate flame or is only heated to start operation, while the heat of evaporation is subsequently taken from the heated inner walls of the charge space itself.
Different methods have also been used to convey the precisely measured amount of petroleum to be separated for the individual charge: either fully developed small pumps are used for this, or the suction effect of the engine piston itself is used to suck in the corresponding petroleum quantity at the same time as the combustion air. The engine systems described below, which are currently mainly commercially available, will provide an overview of the manner in which the various processes for extracting petroleum and evaporating it have mainly been implemented. Apart from the engines that work as actual explosion machines, people are busy, as mentioned in the description of the Brayton gasoline engine in Chapter 3,
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to build double-acting engines with gradual combustion of the mixture as it enters the cylinder. The petroleum engine factory of J. M. Grob in Leipzig-Eutritzsch is already bringing such machines onto the market, and at the end of the chapter this petroleum engine will also be discussed, as far as more details about its construction are known.