The four stroke otto engine uses just one of the four strokes to perform work. This causes various problems: The engine runs jerkily, and this can only be prevented by a large flywheel, which needs a lot of space and weights pretty much in addition.
This obstacle began to be mastered soon: On one hand with a two stroke engine, which will be discussed in the following section, and on the other hand with the combination of several cylinders in multiple-cylinder engines. In these engines, not just every forth stroke work is performed, but - depending on the number of cylinders - more equally. In the following four stroke engine, every half revolution of the crankshaft one of the cylinders has its working stroke.
Cylinder arrangement
The cylinders of an engine can be arranged differently. Each design has its advantages and disadvantages. Here's an description of the most common arrangements, illustrated in each case with a two cylinder engine (twin engine):
The series engine
The four cylinder engine shown above is a series engine, too. The cylinders stand next to each other leading in the same direction. When people wanted to obtain more and more performance on small space, this arrangement became problematic: The cylinders located in a series led to very long engines, the ones with smaller bores and the same cubic capacity led to higher ones. The series engine was used for narrow, elegant engines, which represented once a status symbol in cars with enormous hoods before small windshields.
The opposed cylinder-type engine
Shorter, but broader engines than in a series result in the case of the opposed cylinder-type engine. These were rather common in motorcycles, but today hardly used any more. The cylinders lying far from each other need their own camshafts and even separate carburetors, if the engine is to come to the performance of the series engines. So the opposed cylinder-type engine becomes more expensive and more susceptible to damage.
The V-engine
The very common V-engine offers a good alternative between the two designs discussed above. The engines are not extremely high and long, the cylinders don't lie too far apart. Unfortunately no engine is perfect, and so also the problems of this type can rapidly be seen: The pistons are no longer shifted for half a revolution of the crankshaft at the upper point of reversal, and therefore ignition order and valve timing become more difficult.
2010-2011 umesh engines works, All right reserve
This obstacle began to be mastered soon: On one hand with a two stroke engine, which will be discussed in the following section, and on the other hand with the combination of several cylinders in multiple-cylinder engines. In these engines, not just every forth stroke work is performed, but - depending on the number of cylinders - more equally. In the following four stroke engine, every half revolution of the crankshaft one of the cylinders has its working stroke.
The cylinders of an engine can be arranged differently. Each design has its advantages and disadvantages. Here's an description of the most common arrangements, illustrated in each case with a two cylinder engine (twin engine):
The series engine
The four cylinder engine shown above is a series engine, too. The cylinders stand next to each other leading in the same direction. When people wanted to obtain more and more performance on small space, this arrangement became problematic: The cylinders located in a series led to very long engines, the ones with smaller bores and the same cubic capacity led to higher ones. The series engine was used for narrow, elegant engines, which represented once a status symbol in cars with enormous hoods before small windshields.
The opposed cylinder-type engine
Shorter, but broader engines than in a series result in the case of the opposed cylinder-type engine. These were rather common in motorcycles, but today hardly used any more. The cylinders lying far from each other need their own camshafts and even separate carburetors, if the engine is to come to the performance of the series engines. So the opposed cylinder-type engine becomes more expensive and more susceptible to damage.
The V-engine
The very common V-engine offers a good alternative between the two designs discussed above. The engines are not extremely high and long, the cylinders don't lie too far apart. Unfortunately no engine is perfect, and so also the problems of this type can rapidly be seen: The pistons are no longer shifted for half a revolution of the crankshaft at the upper point of reversal, and therefore ignition order and valve timing become more difficult.
2010-2011 umesh engines works, All right reserve
No comments:
Post a Comment