Happy birthday, four-stroke!

Happy birthday, four-stroke!The 100th anniversary of the internal combustion engine. In one of the magazines last year published an interview with a famous doctor of technical Sciences, a specialist for secure transport, where it was said literally the following: “are You sure, that in the ordinary automobile motor, in fact there are consistently a suction, compression, working stroke of the piston, the exhaust! I’m not sure… In my opinion, at 3-4 thousand revolutions per minute these ticks do not have time nor place nor change each other, and our understanding of them no more than a suitable scheme to calculate…”

 
Of course, this statement does not prevent a doctor to ride in cars equipped with internal combustion engines, the cylinder of which consistently replacing each other, are interspersed those same four bars. And they “time to place” not only for 3-4 thousand, but also at twice and three times high speed, and the “scheme for the calculation” is based not on the subjective views and objective reality, which, of course, are the indicator diagram of these engines.
 
HARNESS FOR A FIRE?HARNESS FOR A FIRE?
 
A little over a hundred years ago only a few people be aware that to ensure the working process of heat engine needs to be replaced by four stroke: suction, compression, working stroke and exhaust. The first who proved this, was a captain in the corps of engineers of France, Sadi Carnot. He I published in 1824 in Paris the book “Reflection on driving force and on the machines capable of developing this power” proposed cycle is a perfect machine for turning heat into work. However, at first the book Carnot, few people paid attention. The young industry of Europe until quite satisfied bulky steam engine.
 
A different situation from the mid-nineteenth century. Nascent everywhere small factories needed a compact engine. One that could be installed in any room, and that he, if not spewed black smoke like a steam machine, and was easy to maintain, and would not require a long time to run.
 
Then began to appear in internal combustion engines. One of them was the engine of Lenoir.
 
170 PATENTS, TO LENOIR?170 PATENTS, TO LENOIR?
 
Jean Lenoir was not a pioneer of the internal combustion engine. By that time only the British register of patents totaled more than 170 patents on engines with combustion in the cylinder. But the engines of the Lenoir, the first of which was built by the end of 1860, has received most a wide circulation.
 
How was it working Lenoir? The motion of the piston (Fig. 1) in one of the cavities of the cylinder — and it should be noted that the car Lenoir was a double action vacuum is formed. Here through the spool absorbed little gas and air. When the piston passes part of its path, in the ignition device passes an electric spark produced by the coil. Ruhmkorff and battery. The spark ignites the gas mixture, combustion products, expanding, topcoat the piston, it drives the crankshaft.
 
Fig. 1. The Engine Of Lenoir
 
Fig. 1. The Lenoir Engine:
 
1 — crankshaft 2 — rod, 3 — rod spool, 4 — the guide of the piston rod, 5 — valve, 6 — piston, 7 — candle.
 
One of the first engines of the Lenoir, with a cylinder diameter of 120 mm and stroke of 100 mm at 130 Rev/MIA developed 0,57 HP Fuel mixture formed from one part gas to nine parts of air. The gas flow was about 3.2 m3 per horsepower per hour. The efficiency of the machine was 4%, ie was equal to the efficiency of the steam engine.
 
However, fuel for this engine costs about six times more expensive than steam. But this disadvantage for small businesses obscures its advantages: the engine was almost silent and smokeless, worked without shaking, did not need a special Foundation. Orders fell to Lenoir everywhere. Since 1860, only two or three decades in France and England was built over 500 engines operating on the principle described above.
 
Meanwhile, in 1863, there was another event, not seen by his contemporaries. In the Paris edition of three hundred copies of the brochure Aphonse Beau de Rocha “a New principle of working of motor vehicles, in which fuel is burned inside the cylinder.” Based on the theoretical developments of Carnot, the author described the practical cycle, the implementation of which would raise the efficiency of internal combustion engines in five or six times. Proposed by Beau de Rocha cycle was to change the suction, compression, stroke and release. According to him, the efficiency of the cycle was determined by preliminary compression of the working fluid. The higher it is, the higher is the expected efficiency.
 
Thus, already in the early 60-ies of the last century had all the conditions for the creation of a four-stroke internal combustion engine. Was developed by cycle, there was a very healthy driven by the engine. It only remained to combine the efforts of the two inventors.
 
But the case is judged differently. Beau de Rochas and Lenoir was found too late, after the beginning of the triumphal March of a four-stroke engine.
 
OTTO OTTO AND A “LEAN”MIXTURE
 
At that time, probably, there was not one technician, who meets his engines of Lenoir, did not give them special attention. I walked by them and Nicholas August Otto. He could not boast of a large education: after graduating from elementary school, the future inventor of what some Peta attended a real school. Then became a salesman, and this occupation was hardly conducive to in-depth self-education. Nevertheless, acquainted with the description of the Lenoir engine, Otto is already in 1861 built the same healthy motor and even made a number of improvements.
 
Otto followed closely the latest developments in the field of internal combustion engines But it so happened that about the works of Carnot on his four-stroke cycle, the implementation of which allowed to sharply bend the efficiency of internal combustion engines, he did not know. No wonder, living in the same time with the Beau de Rocha, he had fifteen pet go on a very long technique of the way — from trial and error.
 
Experimenting with the first engine, Otto established that the burning gases in the cylinder acting on the piston is too small. In his memoirs, which he began writing more than 25 years after these events, Otto said the search of this period: “…the Ignition and combustion should occur at the beginning of the piston stroke. And this idea was immediately tested. I filled the cylinder at 1/2 or 3/4 speed of the working mixture and tried turning the flywheel a stronger grip. Then burned it and immediately noticed that the flywheel was made with great force a few turns”.
 
Speaking many years later, when he had carried out the four-stroke process, Otto rightfully concluded the above quotation with the words: “It was the beginning of a 4-stroke engine.” But at the time he didn’t realize what was happening. He drew attention to another: the piston got too strong jolt.
 
But it should be noted that the main advantages of the engine of Lenoir contemporaries considered quiet and smooth operation. And Otto was no exception. To smooth running of the machine he tried to enter into the design of the buffer pistons creates a resilient air cushion. However, the implementation of this “improvement” led to the accident: due to the strong shaking of the engine broke. Incidentally, during his unsuccessful machine along the way, Otto invented an engine (Fig. 2). He worked in the following way. After ignition of the combustible mixture, the piston went up. Exhaust gases come out, and the pressure under the piston decreased. The outer air acting on the piston, and it fell. This course was the work; during movement of the piston up the rod was not even linked to the motor shaft.
 
Fig. 2. Atmospheric Otto engine.
 
Fig. 2. Atmospheric Otto engine.

 
Universal recognition to the atmospheric engine came after the Paris world exhibition in 1867. During tests conducted at the exhibition, the machine Otto surpassed in efficiency all represented by there heat engines and received a gold medal.
 
Atmospheric engines of joint-stock company “Factory of gas engines Deutz” dispersed around the world. Just by 1877 they had produced 500 total capacity of 6,000 HP On the improvement worked such prominent engineers such as Gottlieb Daimler and Wilhelm Maybach. But despite the increase in output and improvements made to these engines, their capabilities have been exhausted. Engine horse power of more than three SIPS in one cylinder build failed.
 
Meanwhile, the growing industry has forced consumers to turn to other firms, albeit with a more voracious, but powerful motors. In these circumstances, Otto returns to his old experiments, but on a few engines. One is completely destroyed, but the remaining work on a new principle — one working stroke in two revolutions. To improve the smoothness of the piston stroke Otto is experimenting with the poor mixtures.
 
The way for a stable ignition of poor mixtures Otto sees in the application of layer-by-layer filling of the cylinder. It should stay on going, seemingly irrelevant observation may come on sainou idea. In his diaries, Otto writes: “I was constantly tormented by the question of how to burn a poor mixture, and then one day in early 1876, thinking over this question, I noticed smoke coming from the chimney. First, I looked at him like hundreds of times before that, and probably watched by many people, but then I had an Association with the combustible mixture… And then I came to a discovery. I said to myself, if to distribute the fuel mixture is admitted in and PI in the cylinder the air, you get a mixture of the type of smoke, ie at the exit point of the pipes is sealed, but the farther away from the pipe, the less dense it becomes.”
 
ON THE SCALES OF HISTORYON THE SCALES OF HISTORY
 
The power of suggestion was so great that when, after some rework the engine has started, Otto attributed the whole success to the layered cylinder filled with a combustible mixture, not pre-compressed. But the engine worked, he was acquitted of the indicator diagram and filed an application for a patent. This will lead the friend and companion of Otto of Lachen wrote to his wife: “All the flowers of which are in Cologne, come to the feet of an old friend. If we manage to perfect a new car (and with Daimler, we will achieve this), the name Otto is on the scales of history weigh as much as the weight of the name of watt”.
 
The patent for the new engine managed to get only in August 1877, and the same year was put into production the first series of a hundred cars. In General terms, this machine was represented as follows (Fig. 3). The engine is horizontal. Unlike most cars of the time he worked on the principle of double-acting: gases press against the piston on one side only. The piston did not reach the cylinder head by a quarter turn, forming the combustion chamber. To give a more smooth rotation of the motor shaft, in which only one course out of four is working, the flywheel was much heavier than on other machines. Ignition of the mixture is not produced by an electric spark, and gas burner. She gave the flame constantly and it was reported the valve with the working mixture inside the cylinder.
 
Fig. 3. Horizontal four-stroke Otto engine.
 
Fig. 3. Horizontal four-stroke Otto engine.
 
The triumph was waiting for the engine and June, 1878, in the days of the exhibition and Paris. In the French hall demonstrated the excellent performance of the engine of the Lenoir type lightweight. Next, in the German hall, banging and noise was working the gas machine, exhibited by the firm of deytts in Cologne. Externally the car could not stand no comparison with the fine examples of French thermal engines. But… the tests revealed that the efficiency of the Otto motor reaches sixteen percent, while the car Lenoir he is only five. After these trials, the Otto engine was awarded a large gold medal.
 
In the days of the Paris exhibition was held the first meeting of Nicholas Otto with Alphonse Beau de Rocha. Does not claim priority, the happy is the fact that its principle of working of heat engine implemented, Beau de Rocha has finally explained to Otto the main advantage of the invented engine, which consists in the preliminary compression of the mixture.
 
To honor Otto it should be noted that he gained respect for Bo-de-Roche. So, in a letter to Langen he writes: “And who do you think opened my eyes to my own ability! The one you thought our enemy the city of Baux-de-Roche. He became my true friend, explained to me the true meaning of my discovery and how two and two make four, proved that my engine is just a sad mistake on the path to finding the truth.”
 
Happy birthday, four-stroke!
 
So one hundred years has passed since final implementation and the internal combustion engine. Now billions horse SIP, is received in the cylinders, rotate the wheels and screws. Since that time, the efficiency of these engines grew by more than two times. In this regard, I want to quote the words of Nicholas Otto, uttered shortly before his death: “was I not right in saying that this engine will be enough for our descendants a hundred years.” Is PI to add to this statement that now the internal combustion engine is not a worthy opponent!
 
I. ZINOVIEV, engineer