JP2003097201A - Reciprocation mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reciprocation mechanism effective to provide an efficient, compact, and high-performance internal combustion engine capable of reducing its fuel consumption and improving its efficiency of material handling. SOLUTION: The mechanism in which a crankpin is made to perform linear reciprocating motion is adopted, thereby preventing the generation of lateral pressure of a piston and achieving the weight saving of a reciprocating part and the miniaturization of the entire engine.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for converting a rotary motion into a reciprocating motion or a rotary motion into a rotary motion, and is mainly used for an internal combustion engine, a fluid compression device, and the like. Mechanism. 2. Description of the Related Art A conventional reciprocating mechanism is, for example, an internal combustion engine. The structure of the reciprocating mechanism is such that the reciprocating motion of a piston is performed in the order of a piston pin, a connecting rod, a crankpin, a crank arm, and a main journal. This is the configuration transmitted. In the piston, the piston is connected to the connecting rod by a piston pin, and due to the oscillating movement of the connecting rod, the piston receives the side pressure while reciprocating and is pressed against the cylinder bore. The angle of the crankpin is 90 ° from the top dead center and 270 degrees. In the vicinity of °, the lateral pressure becomes maximum, and heat is generated due to the friction resulting in power loss. At the end of the stroke, the direction of the lateral pressure changes to the opposite side, which causes noise, gas leakage, and early wear due to the so-called piston slap where the piston strikes the cylinder bore. These are disadvantageous phenomena because they increase in the tendency of high combustion gas pressure and high speed rotation which are factors of high performance. The shape is also complicated, so that when a certain temperature is reached, the cam is worked so as to have an average clearance with respect to the bore.
In the connecting rod, strength for oscillating motion is required in addition to the strength for transmitting power between the piston and the crankpin, and if the length of the connecting rod is increased, the side pressure of the piston is reduced. Although it is possible, the mass is increasing, which is against the demand for higher performance of the internal combustion engine. [0003] In order to eliminate the above-mentioned drawbacks, the present invention provides a piston rod which does not swing because the connecting rod does not swing by reciprocating the crank pin. The connecting rod can be integrated with the connecting rod. Since there is no generation of lateral pressure, the skirt can be extremely short and the length of the piston can be shortened. . These reduce the weight and size of the reciprocating part. [0004] In the geometry, there is a great circle D and a small circle S, and the great circle D is fixed and the small circle S rotates without slipping while inscribed. Then, the trajectory of the fixed point A of the small circle S is an inner cycloid.
It is. Great circle D when the diameter ratio of great circle D and small circle S is 2: 1
Reciprocation of the diameter line A'-O'-B 'passing through the center O'. The great circle D is replaced with an internal gear and the small circle S is replaced with an external gear, and the gear ratio is set to 2: 1. By arranging the crankpin axis of the crankshaft at the fixed point A of the small circle S and the journal axis at the center O of the small circle, the crankpin reciprocates linearly. Circle C is a locus around the journal axis. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 3, when the connecting rod at the top dead center A 'starts moving in the direction of arrow a, the crankshaft starts to rotate in the direction of arrow c, and the outside of the end portion. Since the gear 2-A meshes with the internal gear,
The output rotor starts to rotate in the direction of arrow e. The output rotor is rotatable by the bearing. The output gear meshing with the gear of the output rotor rotates in the direction of arrow f to extract power from the output shaft. After passing the bottom dead center B ', the connecting rod starts moving in the direction of arrow b and heads toward the top dead center. [0006] One of the main factors that hinder high-speed rotation of the engine is the inertial force of the reciprocating portion. The inertial force increases in proportion to the square of the rotation speed. Reducing the mass of the reciprocating part is an essential condition for improving the performance of the engine. Since the piston does not require a piston pin, no side pressure is generated, which reduces friction loss and shortens the skirt as much as possible.Thus, the pin boss and the pin boss rib are not required, and the piston pin has no mass. Since the shape can be made to be close to the rotating body, deformation due to thermal expansion has no directionality and can be designed to have a uniform gap with respect to the bore, which means that the gap can be smaller than the conventional type Therefore, gas leakage can be reduced. As a result, the occurrence of piston slap can be suppressed, so that noise can be reduced and durability can be improved. Connecting rods can also be shortened. Along with this, the length of the cylinder bore can be shortened, which is a reduction in size and weight of the cylinder block, which is the largest weight part in the internal combustion engine. As described above, high performance, miniaturization, and weight reduction can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a skeleton according to the present invention. FIG. 2 is a schematic diagram of a hypocycloid. FIG. 3 is a schematic diagram of an embodiment. Crankshaft external gear, 2-B crankshaft main journal shaft, 2-C crankshaft arm, 2-D crankshaft crankpin shaft output rotor 3-A output rotor gear section, internal gear bearing output gear output shaft output shaft crankcase A ' Top dead center position of crank pin shaft O Top dead center and bottom dead center position of main journal shaft O 'Output rotor center B' Lower dead center position of crank pin shaft L Full stroke

Claims (1)

Claims: 1. A large end portion of a connecting rod is mounted on a crankpin shaft of a crankshaft via a bearing, and a distance between the crankpin shaft of the crankshaft and the main journal shaft is equal to a full stroke. An external gear is provided at the tip of the main journal shaft of the crankshaft, which is 1/4, and is integral with the crankshaft. An internal gear that meshes with the external gear is fixed to the crankcase side. The gear ratio of this gear is that of the internal gear 2 with respect to the external gear 1. The main journal shaft of the crankshaft is assembled to the output rotor via a bearing. The outer periphery of the output rotor is composed of a bearing and gears. The main shaft of the crankshaft is located at 1/4 of the total stroke from the center of the output rotor. The gear on the outer periphery of the output rotor, in which the journal shaft is incorporated via a bearing, meshes with the gear on the output shaft to transmit power to the output shaft. A reciprocating motion mechanism wherein the crankpin portion of the crankshaft makes a linear motion with the above configuration.