JPH06337013A - Eccentric crank - Google Patents

Abstract

PURPOSE:To provide a crank by which a positive torque is generated all in the expansion stroke. CONSTITUTION:As a method for generating a positive torque all in a crank 1, a roller bearing 3 using a split bush 4 as a crank pin or a half roller bearing is used, and when the outside diameter of the crank pin is enlarged, necessarily the crank becomes eccentric so that all positive torque is generated. An internal combustion engine formed by the eccentric crank is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston type internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, a crank is mainly used as the element for obtaining the rotational torque of an internal combustion engine. Since no detailed literature can be found on the rotational torque generated by the circular orbit drawn by the crank, the rotational torque will be examined first. As shown in FIGS. 1 and 2, if the crank turns clockwise in the upper right half-string, the circular orbit R becomes a resistance at the top dead center point A and the torque is zero. Next, the pressure line P at the point B with the θ angle of 30 ° all works outward from the circular orbit with the circular orbit as a fulcrum, and most of the resistance becomes a combined force and participates in the rotational torque. Therefore, the torque generated up to the tangent line C point increases until reaching the C point and becomes maximum at the pressure line P and the tangent line C of the circular orbit, and no negative torque is generated. On the other hand, the pressure line from the point B on the upper half-string to the point E on the lower half-string, which is perpendicular to the point B, is blocked by the inscribed circular orbit in a non-divergent manner inside the circular orbit, and the bottom dead center F is blocked. If the force is 100%, the stopping power at point E is 90%
I will work around. On the contrary, this blocking force becomes weaker as far as the point D, but the braking force accompanied by the tensile force acts between O and E with respect to the rotational torque. Next, considering the speed condition of the rotating crank that draws a circular orbit, the circular orbit from top dead center to point D is on the acceleration side, and point D to bottom dead center F
The circular orbit leading up to is on the deceleration side. Therefore, while the rotational torque on the acceleration side is the rotational torque diagram when the impact force due to combustion explosion is received, the torque is generated on the deceleration side in the drawing. Since it is rotating while decelerating to the point, the rotation torque is not so effective.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problem of the lower half-string which impedes the rotational torque of the circular orbit delineated by the crank. However, even if it is said that the problem of the lower half-string, the reason why the problem of the lower half-string was solved is that the fulcrum that leads to the generation of torque during the elucidation of torque is not the center point of the crank pin but the piston side It is the upper half string side,
It was discovered that there is an important fulcrum on the outer circumference of the crank pin for the generation of moving torque, and when the drawing is made with emphasis on the moving fulcrum on the outer circumference of the piston pin, the center of the output shaft of the crank and the crank pin It has been found that the crank must be made eccentric by increasing the distance from the outer circumference of the crank, and by making it eccentric, there are many problems such as enlargement of the crank pin, problems of friction due to expansion, problems of preventing expansion, and assembly problems. These problems have been overcome, and the present invention has finally been reached after overcoming many of these problems.

[0004]

[Means for Solving the Problems] As a method for generating all positive torque in a crank, a roller bearing using a split bush or a half roller bearing is used in a crank pin to increase the outer diameter of the crank pin. Inevitably, it will be made eccentric, and all cranks will generate positive torque.

[0005]

[Operation] The torque generation of the crank explained in the prior art is the basic principle of the crank, and the force actually applied to the crank pin is as shown in Fig. 3 on the outer circumference of the crank pin S on the piston side. The outer diameter of the crank pin for generating torque must be taken into consideration because it is applied before the center of the crank pin. Here, let us consider the difference between the eccentric element and the crank element. The eccentric has the center of the output shaft (line XX ') in the eccentric ring as shown in FIG. 5, and in the case of the conventional crank, the center of the output shaft exists outside the outer circumference S of the crank pin. . FIG. 3 is a torque diagram in the case where the output shaft K is larger than the crank pin which is currently used, and is XX ′.
It can be seen that a positive torque is less likely to be generated in the lower half string below the line and a torque that cannot be diverged is exerted between O and W in the orbit. So the limit line X- between this eccentric and crank
It can be seen that when the output shaft is set on the X'line, all the positive torques acting on the upper half string of the torque are ideal as shown in FIG. Therefore, if the crankpin is made large as a measure for improving the torque generation, it is made eccentric to give an advantageous condition for the torque generation. As shown in the drawing, the outer diameter of the entire roller becomes large, which is inevitably made eccentric, and the weight of the crank pin portion with a small frictional resistance does not become too heavy. However, since the roller bearing cannot be directly used for the crank of the four-cylinder internal combustion engine for an automobile, which is a curved shaft, first of all, as shown in FIG. Then, the split bush 4 is press-fitted. Alternatively, the assembly is made possible by inserting the half roller bearing 6 as shown in FIG. Reference numeral 5 is a set screw of the split bush. When the split bush as shown in FIG. 4 is used, the seat height of the crankpin becomes high as shown in FIG. 5, and effective torque is generated even at the point J before bottom dead center. 5 and 6, K indicates the output shaft of the crank. G represents the effective diameter of the entire roller of the roller bearing, and is a key point for torque generation together with the central point H group of the moving piston pin. e indicates the amount of eccentricity. FIG. 7 is a practical view in which the half crank roller bearing is used and the ideal crank and eccentric limits are set.

[0006]

EFFECTS OF THE INVENTION For example, when a rod is used as an arm, the length G-O of the lever, which is important for the generation of torque, which cannot be seen by drawing, is known. Since it can be seen that it becomes shorter and becomes zero until reaching bottom dead center, the eccentric type makes the length of the rod longer and a strong leverage acts on the center 0 point of the output shaft to obtain a strong torque. FIG. 5 shows a structure having a long rod group and generating a strong torque. If the torque increases in this way, it means that not the crank portion has become larger, but other portions such as the piston and the cylinder have become smaller. In order to make such a crank eccentric, an eccentric crank having a roller shaft which is inevitably point-contacted and has little friction due to a roller shaft assembled using a split bush or a half roller bearing in a conventional crank. Thus, it is possible to obtain an internal combustion engine having a high efficiency of only positive rotation torque that smoothly rotates. Further, the method of assembling the crank and the rod by the split bush or the half roller bearing does not require the use of the half metal which has a lot of production man-hours and has a lot of friction due to the surface contact, so that the assembling of the crank and the rod is greatly saved. If half roller bearings are used, the number of production steps will be further reduced because press fitting is not used. By using this half roller bearing, it is possible to make the crankcase the same size as before because no bolts or nuts are required. Also, the eccentric large-sized and space-rich roller shaft has strong durability, smoothes the rotation of the piston and crank, and collects the shock due to combustion and explosion well, so there is less vibration and it can be expected to run smoothly. Become. Further, since a low speed and high torque can be obtained by the crank having a long rod, which is a feature of the present invention, the engine can smoothly run. In the case of other assembled cranks, split bushes and half-roller bearings are not required, but they need to be eccentric to improve torque generation. Next, since the compression stroke is all loaded in any case, it does not affect the performance of the internal combustion engine so much, and the inertia torque of the expansion stroke wraps around and deeply extends to the compression stroke, giving an advantageous condition. is there.

[Brief description of drawings]

[Figure 1]

FIG. 2 is a basic torque diagram of a conventional crank and is a drawing in the order of center points A, B, C, E, and F of a crank pin that rotates and moves. In the figure, the size of each fan-shaped area represents the torque generation rate.

FIG. 3 is a torque diagram including the outer diameter of a conventional crank pin. In the figure, K is the output shaft, S is the crank pin, and e is the amount of eccentricity.

FIG. 4 is an eccentric crank having a roller bearing using the split bush of the present invention.

FIG. 5 is a torque diagram of FIG. 4 of the present invention.

FIG. 6 shows a torque diagram of an ideal eccentric crank of the present invention.

FIG. 7 is a view for implementing the present invention shown in FIG. 6; The direction of rotation in each figure is clockwise.

[Explanation of symbols]

In FIG. Crank 4. Split bush 2. Rod 5. Set screw for split bush 3. Roller Bearing In Fig. 1. Crank 6. Half roller bearing 2. rod

Claims (1)

[Claims] 1. In the expansion stroke of a piston engine, crank torque is generated as a structure for smoothly generating positive torque that works outward from all circular orbits with almost no braking in the rotational direction of the output shaft. The distance between the center point of the output shaft, which is the point, and the outer circumference of the crankpin is increased, and the diameter of the crankpin is increased to make it eccentric, and subsequently the friction and weight of the bearing are increased by enlarging the crankpin. As a method of preventing the above, the crank and rod are assembled by using the roller bearing using the split bush of (4) or the half roller bearing of (6) to assemble the crank with many bending axes and the rod having the roller bearing. An internal combustion engine with a crank that is characterized by being made eccentric by means of roller bearings.