Internal combustion engine

Abstract

An internal combustion engine which includes two parallel crankshafts positioned in crankcases, a cylinder positioned on a side of the crankcases, a piston movably disposed within the cylinder, and connecting rods linked to the piston and extending from respective crankshafts. Positions at which the two connecting rods are linked to the piston and the crankshafts are constantly kept symmetrical with respect to a cylinder axis when the two crankshafts rotate in opposite directions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Certain preferred embodiments of the present invention will be described in detail below, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a sectional view of an internal combustion engine according to the present invention;

FIG. 2 is an oblique view showing an assembly of crankshafts, connecting rods, and pistons according to the present invention;

FIG. 3 is a side elevational view showing an assembly of crankshafts, connecting rods, and pistons according to the present invention;

FIG. 4 is a sectional view of the first crankshaft and the second crankshaft according to the present invention;

FIG. 5 is a schematic view of the first crankshaft and the second crankshaft according to the present invention;

FIGS. 6A through 6C illustrates a piston of the internal combustion engine according to the present invention, wherein FIG. 6A is a sectional view of the piston, FIG. 6B is a sectional view taken along line b-b of FIG. 6A, and FIG. 6C is a view from the bottom of FIG. 6A;

FIGS. 7A and 7B are views showing a first stage operation of the crankshaft, connecting rod, and piston according to the present invention, wherein FIG. 7A is a diagram viewed from the direction extending out from the crankshafts, and FIG. 7B is a diagram viewed from arrow b of FIG. 7A;

FIGS. 8A and 8B are views showing a second stage operation of the crankshaft, connecting rod, and piston according to the present invention, wherein FIG. 8A is a diagram viewed from the direction extending out from the crankshafts, and FIG. 8B is a diagram viewed from arrow b of FIG. 8A;

FIGS. 9A and 9B are views showing a third stage operation of the crankshaft, connecting rod, and piston according to the present invention, wherein FIG. 9A is a diagram viewed from the direction extending out from the crank axis, and FIG. 9B is a diagram viewed from arrow b of FIG. 9A;

FIGS. 10A and 10B are views showing a fourth stage operation of the crankshaft, connecting rod, and piston according to the present invention, wherein FIG. 10A is a diagram viewed from the direction extending out from the crankshafts, and FIG. 10B is a diagram viewed from arrow b of FIG. 10A;

FIG. 11 is a sectional view of a conventional internal combustion engine; and

FIG. 12 is a schematic view showing a synchronizing device of a conventional internal combustion engine.

Claims

1. An internal combustion engine comprising: two parallel crankshafts positioned in crankcases;a cylinder positioned on a side of the crankcases;a piston movably disposed within the cylinder; andconnecting rods linked to the piston and extending from each of the two crankshafts,wherein positions at which the crankshafts and the piston are linked to the two corresponding connecting rods are constantly kept symmetrical with respect to a cylinder axis when the two crankshafts rotate in opposite directions.

2. The internal combustion engine of claim 1, wherein the piston and one of the two crankshafts are linked using one connecting rod, the piston and the other of the two crankshafts are linked using two connecting rods, and one connecting rod is positioned so as to be sandwiched by two connecting rods.

3. An internal combustion engine comprising: two parallel crankshafts positioned in crankcases;a pair of cylinders provided to sides of both crankshafts and to a side of the crankcases so as to be aligned with a cylinder axis;pistons movably disposed within each of the cylinders; andconnecting rods linked to each of the pistons and extend from the two crankshafts to the side of each of the cylinders in the pair,wherein positions at which the crankshafts and the pistons are linked to the corresponding connecting rods linked to the corresponding pistons are constantly kept symmetrical with respect to a cylinder axis when the two crankshafts rotate in opposite directions, and the pistons in the pair each move horizontally.

4. The internal combustion engine of claim 3, wherein the piston and one of the two crankshafts are linked using one connecting rod, the piston and the other of the two crankshafts are linked using two connecting rods, and one connecting rod is positioned so as to be sandwiched by two connecting rods.

5. An internal combustion engine comprising: first and second cylinders provided to the side of crankcases;first and second crankshafts positioned in parallel in the crankcases;a first connecting rod linked at one end to the first crankshaft via a first crankpin;a first piston movably disposed within the first cylinder and linked to another end of the first connecting rod;a second connecting rod linked at one end to the second crankshaft via a second crankpin; anda second piston movably disposed within the second cylinder and linked to another end of the second connecting rod,a distance from an axis of the first crankshaft to the first crankpin and a distance from an axis of the second crankshaft to the second crankpin being equivalent,wherein the internal combustion engine further comprises: pairs of first crank arms provided to the first crankshaft, formed in a tapered shape and supported on a tip by the first crankpin; and pairs of second crank arms provided to the second crankshaft, formed in a tapered shape and supported on a tip by the second crankpin, andwherein the first crank arms and the second crank arms are positioned in parallel, a length of the second crankpin is equivalent to a length of the first crankpin or is longer than the length of the first crankpin, or, alternatively, the length of the first crankpin is equivalent to the length of the second crankpin or is longer than the length of the second crankpin, and the first crank arms are capable of passing through an inner side of the second crank arms and the second crank arms are capable of passing through an inner side of the first crank arms when the first crankshaft and the second crankshaft are rotating.

6. The internal combustion engine of claim 5, wherein an axis of the first crankpin is capable of being positioned further toward an axis of the second crankshaft and away from a straight line that passes through a center between the axis of the first crankshaft and the axis of the second crankshaft, and an axis of the second crankpin is capable of being positioned further toward the axis of the first crankshaft and away from the straight line.