JPH0650322A - Connecting rod structure of engine - Google Patents

Abstract

PURPOSE:To lubricate the small and large ends of a connecting rod respectively through separate systems to give rigidity to the rod part. CONSTITUTION:An oil reserving groove 22 ranging from the proximity of a small end of a connecting rod 8 to the vicinity of a large end 11 is formed on a surface directed upward of the side of the rod part 16 in the connecting rod 8 disposed nearly obliquely in the upper dead point of a piston, and a through hole 18 extending through the inside and outside is formed on the upper end of the small end 9, while a hole 23 is formed which affords communication between the lower end inside of the small end 9 and a groove 22 near the small end 9 of the rod part 16. Spattered oil drops are accumulated in the groove 22 of the rod part 16 and enters inside the lower part of the small end 9 from the hole 23 by an inertia force when the connecting rod 8 descends in the expansion stroke and suction stroke. Also, oil flowing to the large end 11 will be supplied with adjusted pressure. Additionally, the working of the rod part 16 is simplified with the reduction of production cost and the rigidity of the rod part 16 can be improved compared with the conventional one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine connecting rod structure which can be applied to, for example, a V-type engine, a horizontally opposed engine, and an in-line engine which is further inclined and attached to a vehicle body.

[0002]

2. Description of the Related Art Generally, for lubrication in a cylinder of an engine, an oil pump is used or a crankshaft or the like is used so that oil stored in an oil pan adheres to a wall surface of the cylinder, a bearing, a piston pin or the like. I'm scooping up oil.

In the V-type engine 1 shown in FIG. 10, the cylinder 2 is used.
Are arranged in a V shape, a sleeve 3 is fitted in each cylinder 2, and an oil jet nozzle 5 is provided near the bottom dead center position of the piston 4 on the lower end side of the sleeve 3. The piston pin 6 attached to the piston 4 is connected to the ring-shaped small end portion 9 of a connecting rod (hereinafter referred to as connecting rod) 8 with a bush 7 interposed, and the crankshaft 10 is connected to the ring-shaped large end portion 11 of the connecting rod 8. Are linked to. The crankshaft bearing cap 12 supporting the crankshaft 10 is fixed by the crankshaft bearing cap bolt 13.
An oil pan 14 is attached to the lower part of the cylinder 2, and a drain bolt 15 is provided on the lower part of the oil pan 14.

As shown in FIGS. 6 to 9, the connecting rod 8 has a ring-shaped small end portion 9, a rod portion 16 having an H-shaped cross section whose axial side of the crankshaft 10 is a plane, and two upper and lower portions. It consists of a large end 11 which is split and joined by bolts 17. A small saucer-shaped through hole 18 having a tapered inlet is formed in the upper portion of the small end 9. Further, the hole 19 formed in the lower portion of the small end portion 9 and the hole 20 formed in the upper portion of the large end portion are communicated with each other through a communication hole 21 passing through the center of the rod portion 16.

In such a structure, the wall surface of the cylinder 2 is lubricated by the oil blown from the oil jet nozzle 5 by the oil pump. Further, the large end 11 of the connecting rod 8 is lubricated by the oil sent from the hole formed in the crankshaft 10 by the oil pump, and the small end 9 communicates with the oil entering through the through hole 18 in the upper part and the large end 11. It is designed to be lubricated by the oil that comes in through the communication hole 21.

When the crankshaft 10 rotates clockwise as shown by the arrow in the drawing, when the connecting rod 8 rises in the compression process and the exhaust process, the oil droplets scattered above the small end portion 9 Is a saucer-shaped thin through hole due to inertial force
It will enter 18 and lubricate the small end 9. In addition, Japanese Utility Model Laid-Open No. 57-48324 discloses a type similar to a saucer type thin hole.

[0007]

However, in the structure of the connecting rod 8 described above, it is difficult to obtain high fatigue strength because the elongated communication hole 21 is formed in the center of the rod portion 16, and the elongated communication hole is connected to the rod portion 16. It was difficult to process the hole 21 itself. Furthermore, since oil is supplied by an oil pump to lubricate the large end portion 11, when the oil moves to the small end portion 9 from the communication hole 21 that connects the inside of the large end portion 11 and the inside of the small end portion 9, Since the oil pressure inside the large end 11 will decrease, the oil pressure to be sent must be adjusted accordingly, and it will take a lot of time to adjust multiple engines. It was

An object of the present invention is to provide a connecting rod structure for an engine which is rigid and can supply oil sufficiently.

[0009]

In order to achieve the above-mentioned object, the present invention connects a small ring-shaped end connecting a piston and a large ring-shaped end connecting a crankshaft with a rod portion, In the connecting rod assembled so that the rod part is in a substantially oblique posture at the top dead center position of the piston, the connecting rod is attached to the side facing upward of the side part of the rod part from the vicinity of the small end part to the large end part. A groove for the oil sump is formed near the end, and a through hole that connects the inside and the outside of the ring-shaped portion is formed at the upper end of the small end, and the inside of the lower end of the small end and the rod portion are formed. A hole communicating with the inside of the groove near the small end is formed.

[0010]

Since the present invention is configured as described above, the scattered oil droplets collect in the groove of the rod portion,
When the connecting rod descends during the expansion stroke and the suction stroke, the inertial force penetrates the inside of the lower portion of the small end portion from the hole. In addition, the oil flowing to the large end is supplied at a regulated pressure.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 5, a piston 4 is slidably provided inside a sleeve 3 fitted in a cylinder 2 inside the V-type engine 1. An oil jet nozzle 5 is attached below the sleeve 3 so as to face upward inside the piston 4. The piston pin 6 fitted in the piston 4 is connected to the small end portion 9 of the connecting rod 8 via a bush 7. In addition, the crankshaft 10 in the cylinder 2
Is attached to the large end 11 of the connecting rod 8 via a bolt 17.

Since it is a V-type engine, the axis of the piston 4 is inclined with respect to the horizontal plane. Therefore, the rod portion 16 of the connecting rod 8 is arranged substantially obliquely. For this reason, one side surface of the rod portion 16 is directed upward to form a groove 22 having an upward opening. The rod portion 16 is flattened in the axial direction of the crankshaft 10, and the rod portion 16 has an H-shaped cross-section (see FIG. 4).

As shown in FIGS. 1 and 3, a tapered saucer-shaped thin through hole 18 is formed in the upper portion of the small end portion 9 to join the small end portion 9 and the rod portion 16. A hole 23 communicating with the lower portion of the small end portion 9 is opened in the groove 22 near the location.

As described above, since the rod portion 16 of the connecting rod 8 is obliquely arranged and the H-shaped groove 22 is formed therein, the splashed oil droplets are also collected in the groove 22 of the rod portion 16. When the rod portion 16 is in the position shown in FIG. 5, an oil surface 24 is formed on the shoulder of the large end portion 11. When the connecting rod 8 descends during the expansion stroke and the suction stroke, inertial force acts on the rod portion.
The oil collected in the 16 grooves 22 will enter the inside of the small end through the hole 23. The oil surface at this time is indicated by reference numeral 25. It should be noted that the upper portion of the small end portion 9 has oil penetrating from the through hole 18 due to the inertial force when the connecting rod 8 rises in the compression process and the exhaust process due to the through hole 18 formed in this portion.

Therefore, oil is supplied to the small end portion 9 and the large end portion 11 of the connecting rod 8 to lubricate the movable portion. This can be applied not only to the V-type engine in which the connecting rod 8 is obliquely arranged at the position of the top dead center of the piston 4 to allow oil storage, but also to the horizontally opposed engine, as well as the in-line engine that is mounted slantly on the vehicle body.

[0016]

EFFECTS OF THE INVENTION Since the present invention is constructed as described above, the oil accumulated in the rod portion of the connecting rod only needs to be put into the small end portion from the short hole, which simplifies the machining of the rod portion. The production cost can be reduced. Also,
The rigidity of the rod portion can be increased more than that of the rod portion provided with the communication hole. Furthermore, since the oil that lubricates the small end is not supplied from the line of the large end, the oil that is supplied to the large end is in a separate system, so that better lubrication can be performed.

[Brief description of drawings]

FIG. 1 is a front view of a connecting rod that is an embodiment of the present invention.

FIG. 2 is a rear view of the connecting rod shown in FIG. 1 on the large end side.

FIG. 3 is a side view showing the connecting rod shown in FIG. 1 in a partial cross section.

4 is a cross-sectional view of the rod portion of the connecting rod shown in FIG. 3, taken along the line BB.

5 is a sectional view of a cylinder portion of an engine using the connecting rod shown in FIG.

FIG. 6 is a front view showing a conventional connecting rod.

7 is a rear view of the connecting rod shown in FIG. 6 on the large end side.

8 is a side view showing the connecting rod shown in FIG. 6 in a partial cross section.

9 is a sectional view of the rod portion of the connecting rod shown in FIG. 8 taken along the line AA.

10 is a cross-sectional view of a cylinder portion of an engine using the connecting rod shown in FIG.

[Explanation of symbols]

 4 Piston 8 Connecting Rod 9 Small End 10 Crankshaft 11 Large End 16 Rod Part 18 Through Hole 22 Groove 23 Hole

Claims (1)

[Claims] 1. A ring-shaped small end portion for connecting a piston,
A ring-shaped large end that connects the crankshaft is connected by a rod part, and the rod part is assembled so that the rod part is in a substantially oblique posture at the top dead center position of the piston. On the side facing upwards,
A groove for an oil sump is formed from near the small end to near the large end of the connecting rod, and a through hole that connects the inside and the outside of the ring-shaped portion is formed at the upper end of the small end. A connecting rod structure for an engine, characterized in that a hole is formed that connects the inside of the lower end of the small end portion and the inside of the groove near the small end portion of the rod portion.