JPS624764Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to an internal combustion engine that significantly reduces friction loss generated from reciprocating parts, mainly the piston, and rotating parts, such as the rotating bearing of the crankshaft, and significantly improves mechanical efficiency. It is something. It is generally known that a large proportion of friction loss in reciprocating internal combustion engines is generated from reciprocating parts, mainly the piston, and rotating parts, such as the rotating bearing of the crankshaft. It is empirically known that friction loss has the following characteristics. In other words, the friction loss is greater when the explosion pressure and the inertial force of the reciprocating mass are concentrated than when they are dispersed. As the diameter of the bearing of each part increases, it increases in proportion to some power of the diameter, and the exponent is equal to or greater than one. For the same capacity of the engine, it decreases as the number of cylinders increases. Therefore, it can be seen that in order to reduce the friction loss, as the number of cylinders is increased, the number of bearings is increased, the load per bearing is reduced, and the diameter of the bearing is decreased. However, increasing the number of cylinders in the engine not only increases manufacturing costs, but also increases the size of the engine as a whole, which also causes other inconveniences such as poor maintenance. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an internal combustion engine with a simple structure that can reduce the friction loss without increasing the number of cylinders. In order to achieve the above object, the present invention has a piston pin that is horizontally mounted on a piston that is slidably fitted into a cylinder hole formed in an engine body, and a piston pin that is attached to the piston pin at intervals in the axial direction of the pin. The small ends of two connecting rods arranged in parallel with each other are rotatably connected, and the large ends of these connecting rods are connected to a pair formed on the crankshaft at an interval in the axial direction. The crankshaft has a central main shaft portion between the pair of crank pins, and main shaft portions at both ends thereof, and the central main shaft portion and both end main shaft portions are respectively supported by the crank pins of the crank pins. It is characterized by being supported by the engine body via bearings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an internal combustion engine in which a cylinder hole and a piston have an oval or elliptical cross-sectional shape will be described below with reference to the drawings. A cylinder block 1 of the engine body is formed with a cylinder hole 2 having an oval or oval cross section, and a piston 3 having an oval or oval cross section is slidably fitted into the cylinder hole 2. ing. Two pairs of pin bosses 4, 4; 5, 5 are formed in the longitudinal direction of the piston 3, and one piston pin 6 is horizontally suspended between these pin bosses 4, 4; 5, 5. Between each pair of pin bosses 4, 4 and 5, 5, the piston pin 6 has small ends of two connecting rods 7, 8 arranged in parallel at intervals in the axial direction of the pin 6. The connecting rods 7 and 8 are rotatably supported via connecting rods 9 and 10, and the large ends of these connecting rods 7 and 8 are formed symmetrically around one crankshaft 11 with its central main shaft portion 12 in between. It is rotatably supported by a pair of crank pins 13 and 14 via bearings 18 and 21, respectively. Both end main shaft portions 15 and 16 of the crankshaft 11
are rotatably supported on the engine body via one bearing 17, 22, respectively, and the central main shaft portion 12 is supported by two bearings 19, 22 arranged in parallel with each other.
It is rotatably supported by the engine body via 20. A gasket 2 is installed on the top of the cylinder block 1.
A cylinder head 24 is attached through the cylinder head 3, and a combustion chamber 25 is formed by the combustion chamber wall formed on the lower surface of the cylinder head 24 and the upper surface of the piston. Two spark plugs 26 are provided in the combustion chamber 25 with an interval in the longitudinal direction thereof. When the engine is operated and the piston 3 moves up and down in the cylinder hole 2, the power is transferred to the crankshaft 1 via the two connecting rods 7 and 8.
1 and drives it to rotate. By the way, the internal combustion engine configured as described above has two connecting rods 7 and 8 for one piston 3 that is slidably fitted into the cylinder hole 2. is supported by the crankshaft 11 via bearings 18, 21, and the crankshaft 11 is further supported by four bearings 17, 1.
9, 20, and 22, the upper structure of the engine has one cylinder, but the lower structure has two cylinders, and the friction loss of the lower structure is 1. It is assumed that the reduction can be achieved with the same effect as when changing from a cylinder engine to a two-cylinder engine, that is, the number of bearings in the lower structure of the engine is doubled and the friction loss per bearing is the same. In this case, twice as much frictional resistance will occur, but the load per bearing will be reduced to about 1/2, making it possible to reduce the shaft diameter.Friction loss is proportional to some power of the shaft diameter, so Naturally, the friction loss per hit is 1/
2 or less, and it is clear that the overall friction loss is reduced. Also, Number of bearings: N Bearing diameter: D Load on bearings: F Index showing the relationship between shaft diameter and friction
:n, (n>1), then friction loss ∝ ND ⁿ F, and the relationship between the standard type engine and the invented engine is shown in the table below.

[Table] By the way, the diameter D of the bearing is smaller in the proposed engine than in the standard engine, and since n>1, it is clear from the above formula that the friction loss in the proposed engine is smaller than that in the standard engine. be. In addition, regarding the shaft diameter D, when the stress and deflection of each part of the crankshaft are suppressed to a constant value, the engine of this invention not only reduces the load per bearing to 1/2 compared to the conventional standard engine. The spacing between the bearings will also be reduced by about 1/2, so
The bending moment acting on the crankshaft can be significantly reduced, and as a result the diameter of the bearing can be significantly reduced. As described above, according to the present invention, the piston pin 6 is horizontally mounted on the piston 3 which is slidably fitted into the cylinder hole 2 formed in the engine body, and the axis of the pin 6 is mounted on the piston pin 6. The small ends of two connecting rods 7, 8 that are arranged in parallel with an interval in the direction are rotatably connected, and the large ends of these connecting rods 7, 8 are attached to the crankshaft 11. The crankshaft 11 is supported by a pair of crank pins 13 and 14 formed at intervals in the direction via bearings 18 and 21, respectively, and the central main shaft portion 12 is supported between the pair of crank pins 13 and 14. In addition, it has both end main shaft parts 15, 16 at both ends, and the central main shaft part 12 and both end main shaft parts 15, 16 are supported by the engine body via bearings 19, 20; 17; 22, respectively, so that the lower part of the engine The number of bearings in the structure can be approximately doubled compared to conventional ones, reducing the load per bearing, and the main shaft portions 12, 15 of the crankshaft,
16, the span between them is less than half that of the conventional one, and the bending moment acting on the crankshaft 11 is significantly reduced, and the synergistic effect makes it possible to significantly reduce the shaft diameter of each bearing. Therefore, the friction loss of the engine, which is greatly affected by the size of the shaft diameter, can be significantly reduced without increasing the number of cylinders, and the output performance can be improved.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional side view of the internal combustion engine of the present invention, Fig. 2 is a cross-sectional view taken along the lines of Fig.
FIG. 2... Cylinder hole, 3... Piston, 6... Piston pin, 7, 8... Connecting rod,
11...Crankshaft, 12...Central main shaft portion, 1
3, 14... Crank pin, 15, 16... Main shaft portion at both ends, 17-22... Bearing.

Claims (1)

[Scope of utility model registration request] A piston pin 6 is horizontally mounted on a piston 3 that is slidably fitted into a cylinder hole 2 formed in the engine body, and two piston pins are arranged in parallel at intervals in the axial direction of the piston pin 6. The small ends of the connecting rods 7, 8 are rotatably connected, and the large ends of the connecting rods 7, 8 are connected to a pair formed on the crankshaft 11 at intervals in the axial direction. bearings 1 on crank pins 13 and 14 of
8 and 21, and the crankshaft 11
The central main shaft portion 12 is provided between the pair of crank pins 13 and 14, and both end main shaft portions 15 are provided at both ends thereof.
16, the central main shaft portion 12 and both end main shaft portions 1
5, 16 respectively bearings 19, 20; 17; 22
An internal combustion engine that is supported on the engine body via a