RU2267017C2 - Internal combustion engine - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines.

SUBSTANCE: according to invention, engine crankshaft is connected with countershaft through cylindrical gear wheels. Countershaft, in its turn is connected with output shaft through gear wheels with variable gear ratio. Gear wheels with variable gear ratio are elliptical. Flywheel is mounted on output shaft.

EFFECT: reduced losses in operating cycle.

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Description

The present invention relates to internal combustion engines and is intended for use on sea, river, road, rail and power plants.

The closest inventions to the claimed are:

1) An internal combustion engine for which patent RU 2053393 C1 has been issued.

In it, with the help of a complicated connecting rod-crank mechanism, the piston of the two-stroke engine is delayed near the bottom dead center and the purge time of the working cylinder is increased. This engine cannot operate on a four-cycle cycle. In addition, it reduces the duration of the processes of mixture formation and combustion, which will increase the amount of fuel burning on the expansion line, and therefore its consumption.

The increasing complexity of the crank mechanism reduces the reliability of this stressed unit.

2) Internal combustion engine for which the copyright certificate SU 1758258 A1 is issued.

In it, due to the installation of a special gear transmission, which alternately works with different gear ratios, the time for making exhaust, suction, and compression cycles has been reduced, which has increased the number of duty cycles per unit time.

Due to the reduction in the time of the processes of exhaust and suction, the negative work of pumping passages will increase (in quadratic dependence), resulting in an increase in fuel consumption. In addition, since the time of the expansion process remains unchanged, the heat loss during this period does not decrease. Thus, the problem of optimal redistribution of the working cycle time between individual processes is not solved.

Closest to the claimed is an internal combustion engine, for which is issued US patent No. 1191827.

In this engine, torque is transmitted from the crankshaft through a pair of gears with a variable gear ratio to the output shaft on which the flywheel is mounted. Such a device allows in a two-stroke engine, by reducing the time of the compression-combustion-expansion processes, to increase the gas exchange processes.

However, this device cannot be used in a four-stroke engine, as the gear ratio change cycle in it can be (depending on the type of gears) 360 or 180 degrees. In a four-stroke engine, the cycle of which is 720 °, this will result in the time gain obtained in the initial period of the exhaust process and in the final period of the suction process being reduced by reducing the time of the final exhaust period and the initial suction period. Such a redistribution of time will be 360 ° when the gear ratio changes. With a cycle of 180 °, the redistribution of time does not occur either. The device in question for a given type of gears with a variable gear ratio does not allow you to make changes to the resulting redistribution of time between the processes of the cycle.

The device also does not allow changing the phase of oscillations of the angular velocity of the crankshaft with respect to the moment of the start of the working cycle in order to redistribute the time between the processes of the cycle in order to obtain optimal results.

The aim of the invention is to reduce losses in the processes of the working cycle.

The invention is carried out in an internal combustion engine containing a block with cylinders in which pistons are located, connected by connecting rods to crankshafts, an output shaft connected to the crankshafts of each cylinder through gears with a variable gear ratio, and a flywheel mounted on the output shaft. The essence of the invention lies in the fact that the gears with a variable gear ratio are elliptical and connect the output shaft to the crankshafts through conventional cylindrical gears. The crankshaft of the working cylinder is connected through the cylindrical gears to the intermediate shaft, which in turn is connected through the elliptical gears to the output shaft on which the flywheel is mounted.

The invention is illustrated in the drawing, which shows a schematic diagram of an engine that implements the invention.

In the working cylinder 1 there is a piston connected by a connecting rod 3 to the crankshaft 4. Thanks to the cylindrical gears 10 and 9, the crankshaft is connected to the intermediate shaft 11, which in turn is connected through the elliptical gears 5 and 6 to the output shaft 7. On the output shaft 7, a flywheel 8 is installed, which ensures its uniform rotation with a variable angular speed of the crankshaft for one revolution.

The law of variation of the angular velocity of the crankshaft is determined by the law of the gear ratio of the elliptical gears and the gear ratio of the cylindrical gears, as well as the relative position of the crankshaft and the intermediate shaft.

For a four-stroke engine, in order to reduce the time of the compression, combustion, expansion processes and increase the time of the exhaust and suction processes, it is necessary to set the gear ratio of cylindrical gears to 4: 1.

With the location of the piston 2 and the elliptical gears 5 and 6 in the working cylinder 1 shown in the drawing, the expansion process begins at the maximum angular velocity of the crankshaft 4, which reaches the average value by the time the piston arrives at the BDC and continues to decrease to the minimum value throughout the entire stroke .

If the gear ratio of the cylindrical gears is set to 2: 1, then the time of the processes of mixture formation, combustion, and also the time of closing the valves will increase sharply.

For a two-stroke engine, an increase in the time of the processes of mixture formation, combustion and purging is achieved with a gear ratio of cylindrical gears of 2: 1. Reducing the time of compression processes - mixture formation - combustion, expansion (to reduce emissions of nitrogen oxides and heat loss in the walls of the working cylinder) and increasing the time of gas exchange processes will be obtained with a gear ratio of 1: 1.

The performed calculations for a two-stroke engine with a transverse blow, operating according to the above-described principle when changing the gear ratio of elliptical gears in the range from 0.5 to 2.0, compared with a traditional engine, ceteris paribus, showed that the time-section of the exhaust windows increased by 1.4 times, purge - 1.5 times, and the time of the processes of mixture formation and combustion increased 1.8 times. At the same time, the duration of the processes of compression and expansion decreased accordingly. The time of one revolution of the crankshaft in both cases remained constant.

Claims (1)

An internal combustion engine comprising a block with cylinders in which pistons are located, connected by connecting rods to crankshafts, an output shaft connected to the crankshafts of each cylinder through gears with a variable gear ratio, and a flywheel mounted on the output shaft, characterized in that the gears wheels with a variable gear ratio are elliptical and connect the output shaft to the crankshafts through conventional cylindrical gears.