JPH0369811A - Connecting rod of engine - Google Patents

Abstract

PURPOSE:To ensure good lubrication even after a stop for many hours by mounting a lubrication hole which passes through the outer and inner periphery in the end on either of both ends of a connecting rod, and forming the lubrication hole vertically in the upper half section of the end of the connecting rod. CONSTITUTION:A crank bearing 29 and a piston bearing 30 are engaged with both ends 27, 28 of a connecting rod 15 on its inner periphery, and these two bearing 29, 30 are constituted by many rollers 34 arranged in a side bearing 33. An oil guide groove 35 and an oil slit 36 as a lubrication hole are formed on both sides of a large end 27 of the connecting rod 15. Since the oil slit 36 is formed vertically in the upper half section of the large end 27 of the horizontal connecting rod 15, engine oil does not flow out of the engine slit 36 even after an engine is stopped for many hours. Oil is therefore collected in the crank bearing 29, and lubrication in this section is kept in good condition when the engine is restarted.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a connecting rod for a U engine, and in particular relates to one with an improved structure at the end of the connecting rod (prior art) Engine lubrication, Particularly in the lubrication of two-stroke engines, engine oil is mixed into a mixture of gasoline and air, and the mixed engine oil erases TIJ on the piston, crankshaft, and large and small ends of the connecting rod.

Of these, lubrication of both large and small ends of the connecting rod is shown in Figure 5 (
As shown in A), the large end 2 and small end 3 of the connecting rod 1
There is one in which oil guide grooves 4 are formed on both sides of the engine, and engine oil is supplied to bearings (not shown) fitted to the inner peripheries of the large end 2 and small end 3. Further, as shown in FIG. 5(B), the large end 6 of the connecting rod 5 is provided with a plurality of oil guide holes 7 passing through the inner and outer peripheries, and the small end 8 is also provided with similar oil guide holes 7.
Some engines are equipped with an engine to supply engine oil to bearings (not shown) fitted to the inner peripheries of the large end 6 and small end 8.

(Problems to be Solved by the Invention) However, in the conventional example shown in FIG. There is a possibility that sufficient engine oil cannot be supplied to the bearing, resulting in insufficient lubricity.

Furthermore, in the conventional example shown in FIG. 5 (8), although engine oil is sufficiently supplied to the bearing through the oil guide hole 7, the oil guide hole 7 is Since it is also formed in the lower half of the direction, when the engine is stopped for a long time, the large end 6 or the small end 8
The engine oil stored therein flows out through the oil guide hole 7. As a result, the lubricity may become insufficient when the engine is restarted after being stopped for a long period of time.

The present invention has been made in consideration of the above circumstances, and it is an object of the present invention to provide an engine connecting rod that can improve the lubricity between the connecting rod and the crankshaft or piston even when the engine is restarted after being stopped for a long period of time. .

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a crankshaft and a piston connected to both ends of a connecting rod via bearings, in which the bearings are fitted to the inner peripheries of both ends of the piston. and at least one of both ends of the connecting rod is provided with a lubrication hole that penetrates the outer and inner peripheries of the end, and the lubrication hole is formed in the upper half of the end of the connecting rod in the vertical direction. It is characterized by:

(Function) Therefore, according to the engine connecting rod according to the present invention, the lubricating hole penetrating through the connecting rod end is formed in the vertical upper half of the connecting rod end, so that the engine can be used for a long period of time. When the engine oil is stopped, the engine oil in the connecting rod end does not flow out from the lubrication hole, but remains in the connecting rod end for a long period of time. Therefore, even when the engine is restarted after being stopped for a long period of time, the lubricity between the connecting rod and the crankshaft or piston is good.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1(A) is a side view showing one embodiment of an engine connecting rod according to the present invention, and FIG. 1(B) is a side view showing one embodiment of the connecting rod of an engine according to the present invention.

(C) GetFigure 1 (A) (7) IB-IBIi, I
A sectional view taken along the C-IC line, Figure 2 is similar to Figure 1 (A
).

FIG. 2 is a partially cutaway side view of a two-stroke engine and its air supply system to which the connecting rods of FIGS. 2A and 2B are applied. FIG.

In a two-stroke engine 1o shown in FIG. 2, a cylinder 13 is arranged substantially horizontally in a cylinder block 12 joined to a crankcase 11.

A piston 14 is housed in the cylinder 13 so as to be reciprocally movable, and a crankshaft 16 is connected to the piston 14 via a connecting rod 15.

The crankshaft 16 is rotatably supported by the crankcase 11. Further, a cylinder block 18 in which a combustion chamber 17 is formed is joined to the upper part of the cylinder block 12.

A suction portion 11A is formed in the crankcase 11 above the axis of the cylinder 13 in the vertical direction.

A reed valve 19 is installed in this suction portion 11A, and an inlet manifold 20 is connected thereto. A carburetor 21 is located upstream of this inlet manifold 20.
and air cleaner 22 are sequentially connected. Therefore, during the suction/compression process of the two-stroke engine 10 (the state shown in FIG. 2), the air cleaner 22 and the carburetor 21
The air-fuel mixture generated at is sucked into the crankcase 11 through the reed valve 19 by the negative pressure within the crankcase 11, as shown by arrow A. Also, at the same time as this inhalation,
By moving the piston 14 to the top dead center, the cylinder 13
The air-fuel mixture inside is compressed.

During the explosion/scavenging process that follows the suction/compression process, the piston 14 is pushed toward the bottom dead center, the crankshaft 16 is rotated by the connecting rod 15, and the exhaust gas in the cylinder 13 is moved toward the cylinder block. 12 exhaust boat 23, and furthermore, the crankcase 11
The air-fuel mixture inside flows into the cylinder 13 from the scavenging bow 24 through a scavenging passage (not shown) as shown by arrow B. Here, arrow C indicates the rotation direction of crankshaft 16.

By the way, an oil tank 26 is connected to the inlet manifold 22 through an oil pipe 25, and engine oil flows into the inlet manifold 2 when the air-fuel mixture is taken in.
0 is supplied as shown by the arrow. The engine oil supplied into the inlet manifold 20 is atomized within the inlet manifold 20 and mixed into the air-fuel mixture, and flows into the crankcase 11 together with the air-fuel mixture. The engine oil mixed into the air-fuel mixture lubricates the bearing portion of the crankcase 11 and the large end 27 of the connecting rod 15, and further lubricates the piston 14, the small end 28 of the connecting rod 15, and the like.

Now, as shown in FIG. 3, a crankbin bearing 29 and a piston pin bearing 30 are fitted to the inner peripheries of the large end 27 and small end 28 of the connecting rod 15, respectively. The crankbin 31 is inserted into the crankbin bearing 29, and the connecting rod 15 is rotatably connected to the crankshaft 16. Further, the piston pin 30 is inserted into the piston bearing 30, and the connecting rod 15 is rotatably connected to the piston 14.

As shown in FIG. 4, in the crankbin bearing 29 and the piston pin bearing 30, a large number of rollers 34 are disposed between a pair of opposing side rings 33 in the circumferential direction of the side link 33. It was constructed as follows.

The large end 27 of the connecting rod 15 is shown in FIG. 1(A).

As shown in (B) and (C), oil guide grooves 35 are formed on both sides thereof. Further, the large end portion 27 includes ai
An oil slit 36 as an m-hole is also formed. This oil slit 36 is formed in the upper part of the connecting rod 15 in the vertical direction outside the large end 27 of the connecting rod 15 which is arranged substantially horizontally, that is, in the upper part of the connecting rod 15 shown in FIG.
It is formed on the intake section 11A side of the cycle engine 10.

Further, this oil slit 36 is formed in a circular arc shape with a radius R. Further, an outer circumferential guide groove 37 is formed in the opening on the outer circumferential side of the large end 27 of the oil slit 36, and an inner circumferential guide groove 38 is formed in the opening on the inner circumferential side of the large end 27. The outer circumferential guide 37 is formed into an arc shape with a radius of "."

In this way, the oil slit 36 is formed in the large end 27 of the connecting rod 15, and since the oil slit 36 is formed in the upper half of the large end 27 in the vertical direction, it is possible to stop the two-stroke engine 10 for a long period of time. Sometimes the engine oil in the big end 27 does not flow out from the oil slit 36,
It is stored in the crankbin bearing 29 disposed within the large end 27 for a length of 11 minutes. Therefore, even if the engine is restarted after being stopped for a long time, the crankbin bearing 29 is sufficiently lubricated, and therefore the connecting rod 1
5 and the crankshaft 16 are improved.

Furthermore, the oil slit 36 formed in the vertical upper half of the large end 27 is provided on the suction section 11A side of the crankcase 11 in this two-stroke engine, as shown in FIG. The engine oil mixed into the air-fuel mixture can easily enter the oil slit 36 through the reed valve 19. As a result, even during engine starting, oil is not sufficiently supplied to the crankbin bearing 29.
Improves slipperiness.

Furthermore, since the oil slit 36 is provided at the large end 27 of the connecting rod 15, the oil slit 36 is shown in FIG.
Compared to the case where a large number of oil guide holes 7 are formed as in the conventional example B), a decrease in the strength of the connecting rod 15 can be avoided.

In addition, since oil guide grooves 37 are also formed on both sides of the large end portion 27, the oil guide grooves 37 also promote the supply of oil to the crankbin bearing 29, thereby improving the lubricity of the crankbin bearing 29. will improve.

In addition, according to the above embodiment, the large end 2 of the connecting rod 15
Although the oil slit 36 is formed in the small end portion 28, a similar oil slit may be formed in the small end portion 28.

Further, in the above embodiment, the two-stroke engine 10 in which the cylinder 13 is arranged horizontally has been described, but the cylinder 13
may be arranged substantially vertically. Also in this case, the oil slit is formed in the vertically upper half of the large end or the small end.

Further, in the above embodiment, the two-stroke engine 10 has been described, but the present invention may be similarly applied to a connecting rod of a four-stroke engine.

〔Effect of the invention〕

As described above, according to the engine connecting rod according to the present invention, at least one of both ends of the connecting rod has a ra
A lubrication hole is drilled through the outer and inner periphery of the connecting rod, and since this lubrication hole is formed in the vertically upper half of the end of the connecting rod, the engine oil in the end can be maintained even when the engine is stopped for a long time. No leakage occurs, and as a result, good lubricity between the connecting rod and the crankshaft or piston can be maintained even when the engine is restarted after being stopped for a long time.

[Brief explanation of drawings]

1(A) is a side view showing one embodiment of the engine connecting rod according to the present invention, FIG. 1(B>) is the F1 view (A) (7) IB-IBI!i, IC −
Cross-sectional views along the IC line, Figure 2 is Figure 1 (^) (
Part 3 is a partially cutaway side view of the two-stroke engine and its air supply system to which the connecting rods of B) and (C) are applied.
The figure is an enlarged side view of the main part of Figure 2, and Figure 4 is a side view of the main part of Figure 3.
A perspective view showing the crankbin bearing in Figure 5 (A
) and (B) are side views showing a conventional connecting rod, respectively. DESCRIPTION OF SYMBOLS 10... 2-cycle engine, 11... Crank case, 11A... Suction part, 14... Piston, 15
...Conrod, 16...Crankshaft, 27
... Big end of connecting rod, 28... Small end of connecting rod, 29... Crankbin bearing, 30...
Piston pin bearing, 36...oil slit.

Claims (1)

[Claims] The crankshaft and the piston are connected to both ends of the connecting rod via bearings, and the bearing is fitted to the inner periphery of each end of the piston, and at least one of the ends of the connecting rod includes: 1. A connecting rod for an engine, characterized in that a lubricating hole is bored through the outer circumference and inner circumference of the end, and the lubricating hole is formed in the upper half of the connecting rod end in the vertical direction.