Dugald Clerk developed
Dugald Clerk developed the first two cycle engine in 1879. It used a separate cylinder which functioned as a pump in order to transfer the fuel mixture to the cylinder.6
In 1899 John Day simplified Clerk's design into the type of 2 cycle engine that is very widely used today.13 Day cycle engines are crankcase scavenged and port timed. The crankcase and the part of the cylinder below the exhaust port is used as a pump. The operation of the Day cycle engine begins when the crankshaft is turned so that the piston moves from BDC upward (toward the head) creating a vacuum in the crankcase/cylinder area. The carburetor then feeds the fuel mixture into the crankcase through a reed valve or a rotary disk valve (driven by the engine). There are cast in ducts from the crankcase to the port in the cylinder to provide for intake and another from the exhausst port to the exhaust pipe. The height of the port in relationship to the length of the cylinder is called the "port timing."
On the first upstroke of the engine there would be no fuel inducted into the cylinder as the crankcase was empty. On the downstroke the piston now compresses the fuel mix, which has lubricated the piston in the cylinder and the bearings due to the fuel mix having oil added to it. As the piston moves downward is first uncovers the exhaust, but on the first stroke there is no burnt fuel to exhaust. As the piston moves downward further, it uncovers the intake port which has a duct that runs to the crankcase. Since the fuel mix in the crankcase is under pressure the mix moves through the duct and into the cylinder.
Because there is no obstruction in the cylinder of the fuel to move directly out of the exhaust port prior to the piston rising far enough to close the port, early engines used a high domed piston to slow down the flow of fuel. Later the fuel was "resonated" back into the cylinder using an expansion chamber design. When the piston rose close to TDC a spark ignites the fuel. As the piston is driven downward with power it first uncovers the exhaust port where the burned fuel is expelled under high pressure and then the intake port where the process has been completed and will keep repeating.
Later engines used a type of porting devised by the Deutz company to improve performance. It was called the Schnurle Reverse Flow system. DKW licensed this design for all their motorcycles. Their DKW RT 125 was one of the first motor vehicles to achieve over 100 mpg as a result.14
Where to work in the automotive industry?
While working in the garage is the most common employment opportunities for people fascinated with the automotive industry, it is certainly not the only option that we can choose where we want to take up employment in this industry. Very interesting, though perhaps sometimes quite tedious task for people interested in the subject is the position of consultant in showrooms respective car brands. You have to admit, however, that in order to obtain employment in a place like this should have appropriate knowledge and skills, especially in dealing with customers. Many options of employment also provides production vehicles of different types or auto parts. Employment in this place very often involves simple tasks.
Why are vehicles that frequent prizes?
We can easily notice that the cars or motorcycles are very often one of the main prizes in various competitions or sweepstakes. Why is it like that ? Well, these machines are often very valuable and can significantly make life easier for the winner. So valuable prize is designed to encourage more participants to take part in the common play or boot from the competition. It is a very proven grip, which for years makes competitions with prizes automotive enjoyed considerable popularity. Admittedly, win a car or a motorcycle or any other vehicle is also associated with considerable charges, which obliges us right relating to competitions; not discouraged, however, many taking part in all kinds of lotteries.