In 1859 and 1860 Stephen Wilcox patented an improved air engine, that became the renowned Wilcox hot air engine built in the following years.
This engine was used in any manufactories and was famous due to it exceptionnal characteristics.
The hot air engine will be presented by means of three articles and three patents.
First an overview is given by Archive 1, an article of Scientific American. The general principle are presented in order to understand the basics of the engine.
Second, the Archive 2 is a masterpiece of Conrector G. Delabar. It exposes a structured presentation of the engine, utmost detailled as the author had a sound understanding of heat engines and examined the Wilcox's engine by himself. Much appreciated he his efforts to describe the functionning of the central valve together with the excess pressure variation in each engine revolution.
The author having been German, it should be noted that in Germany the hot air engine were usually called a hot air machine or caloric machine.
Third, the Archive 3 is an article of Practical Mechanic's Journal. Its presentation is complementary to the two other ones. The regenerator, that has been briefly describe in the former articles, is here well introduced and explains the role of the central cone. The transformation of this open-cycle engine into a closed-cycle machine is also described. At last many other details are given that are not present in the two previous archives.
will give a description of another version of the same engine. It approach is similar to the above, but as the presented engine differs somehow from the previous one, it helps to better understand the principles of hte Wilcox technology.
These three articles have been written at the time the engine was invented and built, approximately in 1860-1861. There are some overlappings, but each of them gives particular details that help to understand the whole engine.
It should be clear that this hot air engine had several version and improvements.
Funny is to see that the titles of these articles that varies according to the journal: air engine, air machine or caloric machine are all expressions that are related to the same hot air engine.
Besides these precise and exhaustive articles, two patents, of 1859 and 1860, will be presented and commented.
After 1860, Wilcox patented two other engines, in 1865 and 1883. The former one had little succes and will be briefly presented.
The latter one, the hot air engine of 1883 will also be presented through the analysis of the related patent and further gathered information.