JPH02223638A - engine - Google Patents

Abstract

PURPOSE:To obtain a compact engine with a starting motor not to accept thermal effect due to exhaust system by arranging the starting motor at a recessed portion which is formed by the envelope of a connecting rod and the envelope of a balancer. CONSTITUTION:The mating face 8a of a split bearing 8 for a connecting rod 7 is inclined downwardly to the left. In such a way, the envelope alpha of a connecting rod 7 is drawn in the shape that the mating face 8a of the split bearing 8 is recessed to the side of a crank shaft 2 at (A) and (B) portions, compared with the envelope beta of the connecting rod inclined upwardly to the left. So, for this engine, the inner wall 9a of a crank case 9 is faced to a recessed portion which is formed by the envelope alpha of the connecting rod 7 and the envelope of the second balancer 4, e.g. the outer periphery of a gear 4a, and at the recessed portion 9b, formed thereby, in the outer wall of the crank case 9 a starting motor 10 is arranged, which is fixed to the frange-shaped portion 9c of the crank case.

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to an engine, and more particularly to an installation structure for a starting motor.

b. Prior Art FIG. 4 shows a conventional vertical shaft engine.

In this engine, a balancer C is disposed on the opposite side of the cylinder b with respect to the crankshaft a, and the peripheral wall e of the crankcase d has an envelope g of the connecting rod r.
and the balancer C.

C1 Problems to be Solved by the Invention In the engine, the starting motor r is installed outside the crankcase d. In such an engine, in order to make the whole engine compact, the starting motor h is disposed close to the cylinder block i, as shown by the two-dot chain line.

However, if the starting motor h is disposed in this manner, it will be close to an exhaust system, such as a muffler, and will be easily affected by heat. Also, starting motor h
As shown by the solid line, if it is placed away from the exhaust system, the width of the engine (distance from the center of the crankshaft to the outer shell of the starting motor h - 8) increases.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a compact engine in which the starting motor is not affected by heat from the exhaust system.

d. Means for Solving the Problems In the engine of the present invention, in an engine in which a balancer is disposed on the opposite side of the cylinder with respect to the crankshaft, the balancer is formed by the envelope of the connecting rod and the envelope of the balancer. A circumferential wall of the crankcase faces the concave portion, and a starting motor is attached to the circumferential wall, and the mating surface of the split bearing of the connecting rod is arranged so as to move away from the cylinder as it goes in the direction of the starting motor. It is tilted to

e. Embodiment FIGS. 1 and 2 show an engine according to the present invention,
It shows a 4-stroke vertical shaft engine.

This engine is installed in the aircraft body, etc. with its right side facing down in FIG. However, in the following description, the cylinder 1 is arranged vertically.

In this engine, first and second balancers 3 and 4 are arranged below the crankshaft 2, a camshaft 5 is arranged diagonally above the crankshaft 2, and a first
A governor 6 is disposed diagonally above the balancer 3 and below the camshaft 5.

The gear 3a of the first balancer 3 is meshed with the gear 2a of the crankshaft 2, and the gear 4a of the second balancer 4 and the gear 6a of the governor 6 are meshed with the gear 3a of the first balancer 3. . Further, the gear 5a of the shaft 5 is meshed with the gear 2b of the crankshaft 2.

In this engine, the split bearing 8 of the connecting rod 7
As shown in FIG. 1, the mating surface 8a of the
As is clear from the figure, the envelope α of the connecting rod 7 aligns the mating surface 8a of the split bearing 8 with the envelope β of the connecting rod tilted upward toward the left as shown in FIG. In comparison, parts A and B are recessed toward the crankshaft 2 side. Therefore, in this engine, the inner peripheral wall 9a of the crankcase 9 is made to face the four parts formed by the envelope α of the connecting rod 7 and the envelope of the second balancer 4, that is, the outer peripheral line of the gear 4a in the embodiment, A starting motor 10 is arranged in the outer peripheral wall recess 9b of the crankcase 9 formed thereby,
The motor 10 is fixed to a flange-shaped portion 9r of the crankcase 9. And this starting motor 10
The gear 10a is the ring gear 2 of the crankshaft 2.
It is meshed with c.

In this way, in the engine in which the starting motor 10 is arranged, the motor l is connected from the center of the crankshaft 2.
The convergence to the outer shell of O is small (this means that the ring gear 2c is also small, and the weight is also reduced.

Further, in the above engine, as shown in FIG. 3, since the envelope α of the connecting rod 7 is concave at the B portion, the first balancer 3 can be brought closer to the crankshaft 2 side, and accordingly The governor 6 can also be moved closer to the crankshaft 2 side. As a result, in this engine, the width -3 to the right from the crankshaft a of the conventional engine shown in FIG. (the outer shell of the gear 5a) is the radius w4, and the size can be made that much more compact.

In the above embodiment, a four-cycle vertical shaft engine is shown, but the present invention is not limited thereto, and may be an engine in which the crankshaft 2 is horizontally disposed on the aircraft body, or an engine equipped with a push rod 11. In other words, the engine may be an engine that does not have a camshaft 5, or may even be a two-cycle engine.

f. Effects of the Invention As described above, in the engine according to the present invention, the width of the engine is reduced because the starting motor is disposed in the recess formed by the envelope of the connecting rod and the envelope of the balancer. , and the ring gear is also smaller, which reduces weight. Furthermore, since the starting motor is installed away from the exhaust system, it is not affected by any adverse thermal effects.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing an engine according to the present invention, and FIG. 3 is a diagram comparing the envelope of the connecting rod of the engine of the present invention with the envelope of the connecting rod of a conventional engine. FIG. 4 is a sectional view showing a conventional engine. l...Cylinder, 2...Crankshaft, 2a, 2b, 2cm gear, 3.4...Balancer, 3a, 4b...Gear, 5...Camshaft, 5a...Gear, 6 ...Governor, 6a...Gear, 7...Connecting rod, 8...Split bearing, 8a...Mating surface, 9...
- Crank case, 9a...Inner circumferential wall, 9b...Outer circumferential wall, 9c...Flanged portion, 10...Starting motor, 10a...Gear, α...Envelope.

Claims (2)

[Claims] (1) In an engine in which a balancer is disposed on the opposite side of the cylinder to the crankshaft, the circumferential wall of the crankcase faces the recess formed by the envelope of the connecting rod and the envelope of the balancer, and An engine characterized by having a starting motor attached to the peripheral wall. (2) The engine according to claim 1, wherein the mating surfaces of the split bearings of the connecting rod are inclined so as to move away from the cylinder as they move toward the starting motor.