JP2000104560A - Two-cycle multi-cylinder internal combustion engine using forcible scavenge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce vibration in operation of an internal combustion engine by arranging an even number of cylinders opposedly in a forcible scavenge type two-cycle multi-cylinder internal combustion engine and igniting cylinders on the same top dead center simultaneously for operation. SOLUTION: In application to an eight-cylinder engine, four pairs of cylinders consisting of paired cylinders 1 and 2, 3 and 4, 5 and 6, 7 and 8 arranged opposedly to each other are arranged along a crankshaft 29 common to the respective four pairs. In each of the cylinders 1-8, an exhaust port, an intake port, and a fuel jetting port are formed while an ignition plug is installed toward a combustion chamber. Exhaust emission in the cylinder is forcibly discharged from the exhaust port by means of air sucked from the intake port according to the rotation of the crankshaft 29. Subsequently, air inside the cylinder is compressed, fuel is sucked from the fuel injection port and a spark is generated in the ignition plug for burning the fuel, and power is given to a piston for rotating the crankshaft 29. In this process, operation is controlled so that cylinders on the same top dead center are ignited simultaneously, and consequently, generation of vibration can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to an arrangement of cylinders of a two-cycle multi-cylinder internal combustion engine using forced scavenging and an internal combustion engine whose vibration is reduced by an ignition sequence thereof.

2. Description of the Related Art Many conventional internal combustion engines have cylinders arranged in series or in a v-shape, and have the disadvantage that vibrations are likely to occur along the direction of movement of the internal piston.

[Problems to be Solved by the Invention] In a conventional reciprocating internal combustion engine, a piston that moves due to combustion or explosion in a cylinder moves at a position symmetrical with respect to a crankshaft. Vibration occurs in the direction of motion, which causes the entire engine to vibrate.

According to the present invention, the arrangement of the cylinders is arranged so as to be symmetrical when viewed from the crankshaft, and a plurality of ignitions are simultaneously performed when the arrangement becomes symmetrical when viewed from the crankshaft.
The purpose is to eliminate the cause of the vibration by making the kinetic forces of the pistons cancel each other.

[Means for Solving the Problems] In order to solve the above-mentioned object, in the internal combustion engine of the present invention, an even number of cylinders are arranged in an opposed type, and the ignition timing is set at such a point that the kinetic forces of the pistons cancel each other. In order to reduce the vibration of the engine itself.

[Embodiment of the Invention] An embodiment of the invention will be described based on an embodiment with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example in which eight cylinders are arranged in an opposed manner as an example of the present invention. The cylinder 1 is mounted so as to face the cylinder 2 as shown in the vertical sectional view of FIG. 2, and the cylinder 3 and the cylinder 4 are mounted side by side with the cylinder 1 and the cylinder 5 and the cylinder 6, and the cylinder 7 and the cylinder 8 in the same manner. They are mounted side by side on a facing type. A piston 9 is provided in the cylinder 1, a piston 10 is provided in the cylinder 2, and pistons 11, 12, 1 are provided in the cylinders 3, 4, 5, 6, 7 and 8.
3, 14, 15, and 16 are respectively fitted to form an eight-cylinder.

The connecting rod 17 of the piston 9 has the same crank 1 as the connecting rod 18 of the piston 2.
9, the connecting rod 20 of the piston 11 is connected to the common crank 22 with the connecting rod of the piston 12, the connecting rod 23 of the piston 13 is connected to the common crank 25 of the connecting rod 24 of the piston 14, and the connecting rod of the piston 15 is connected. The grod 26 is fitted on a common crank 28 with a connecting rod 27 of the piston 16.

The cranks 19, 22, 25, and 28 are mounted on the same straight crankshaft 29. The cranks 19 and 28 are fixed at the same phase, and the cranks 22 and 25 are fixed at positions opposite to each other by 180 °. , The crankshaft 29 has bearings 30, 31, 32,
It is rotatably supported by 33,34. With the above configuration, the pistons 9, 10, 15, 16 are in phase with each other,
The pistons 11, 12, 13, and 14 move linearly in each cylinder simultaneously in the opposite phase.

Each cylinder has an exhaust port 35, a supply port 36, and a fuel injection port 3 as shown in a schematic sectional view of the cylinder 1 and the cylinder 2 in FIG.
7, has a spark plug 38, and forcibly discharges waste air in the cylinder from the exhaust port by blowing pressure air from the intake port 36 in accordance with the rotation of the crank 19, and then compresses the air in the cylinder to inject fuel. After the fuel injected through the port 37 and the fuel fired from the ignition fire plug 38 burn or explode the fuel injected by diesel ignition or electric ignition, the piston performs a necessary operation, and then returns to the original exhaust state. As a result of each cylinder repeating the above operation, the cylinders 1, 4, 6, and 7 burn or explode at the same time, and after the crank 19 rotates 180 °, the cylinders 2, 3, 5, and 8 burn or explode at the same time. By repeating the above, the crankshaft 29 continues to rotate, and power can be taken out therefrom.

As described above, the cylinders 1 and 7 and the cylinders 4 and 4
As a result of the simultaneous combustion or explosion of 6, the directions of action of the forces cancel each other, and the inertial forces of the pistons 9, 10, 15, 16 and the pistons 11, 12, 13, 14 also cancel each other. Similarly, the acting force at the time of combustion or explosion in the cylinders 2 and 3 and the cylinders 5 and 16 also cancels out.
Each of these acting forces originally causes vibration of the engine, but by acting in a direction in which all of these acting forces cancel each other, the cause of causing the entire engine to vibrate is extremely reduced, and the vibration of the engine is reduced. Decrease. Although the present embodiment uses the case of eight cylinders, it is needless to say that a similar effect can be obtained also with a multiple of 16 cylinders or the like.

Further, in the present invention, as described above, the forced exhaust is used to discharge the in-cylinder waste air. Since the mixture of fuel and lubricating oil does not pass through the crankcase 39, the lubricating oil 40 is stored therein. The oil can be hooked and refueled by the laying oil scraper 41. Therefore, it is not necessary to use a mixed oil with the lubricating oil as the fuel, and the exhaust gas can be kept clean.

Next, an example in which the present invention is applied to a four-cylinder engine will be described. As shown in FIG. 3, the cylinder 42 and the cylinder 43 face each other,
The cylinders 44 and 45 are also opposed to each other and are arranged in parallel. The pistons 46 and 47 in the cylinders 42 and 43 are connected to a crank 50 by connecting rods 48 and 49, respectively, and the crank is fixed to a crankshaft 51. Similarly, the pistons 52 and 53 in the cylinders 44 and 45 are also connected to the crank 56 by the connecting rods 54 and 55, and the crank is also connected to the crankshaft 51. The crank 56 is fixed by being shifted from the crank 50 by 180 °. This configuration is the same as the half configuration of the eight cylinders.

[0013] Also in this four cylinder, the cylinder 42 and the cylinder 45
Are burned or exploded at the same time, and after half a crankshaft rotation, the cylinders 43 and 44 are operated to burn or explode at the same time to continue rotation. In this case, due to the action force due to combustion or explosion and the inertia force of the piston, a rotational vibration is generated around the center of the crankshaft 51, but the vibration in the movement direction of the piston is less outside the engine due to the cancellation of the action force. Does not appear large. Therefore, transmission of vibration to the outside can be considerably reduced by properly considering the method of supporting the entire engine.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an eight-cylinder engine.

FIG. 2 is a longitudinal sectional view of the part.

FIG. 3 is a schematic cross-sectional view when implemented in a four-cylinder engine.

[Explanation of symbols]

1,2,3,4,5,6,7,8 Each cylinder 9,10,11,12,13,14,15,16 Each piston 17,18,20,21,23 contained in the above-mentioned cylinder , 24, 26, 27 Connecting rod connected to each piston 19 Crank connected to connecting rods 17, 18 22 Crank connected to connecting rods 20, 21 25 Crank connected to connecting rods 23, 24 28 Connectin rod Crank 29 coupled to grods 26, 27 29 Crankshaft 30, 31, 32, 33, 34 Bearing 35 Exhaust port 36 Supply port 37 Fuel injection port 38 Spark plug 39 Crankcase 40 Lubricating oil 41 Oil scraper 42, 43, 44 , 45 Each cylinder 46, 47 in the example of four cylinders Each piston 48 accommodated in the cylinders 42, 43 49 Connecting rods connected to the pistons 46 and 47 50 Cranks 51 connected to the connecting rods 48 and 49 Crankshafts 52 and 53 for fixing the crank 50 Pistons 54 and 55 accommodated in the cylinders 44 and 45 Piston 52 , 53 connected to connecting rods 54, 55 and fixed to crankshaft 51.

Claims (1)

[Claims] A two-cycle multi-cylinder internal combustion engine using forced scavenging in which even-numbered cylinders are arranged in an opposed type and cylinders at the same top dead center are simultaneously ignited to reduce vibration.