JPS595128Y2 - Internal combustion engine lubrication system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lubricating device for an internal combustion engine, and more particularly to a lubricating device for sliding parts such as a crankshaft and a piston pin in a reciprocating engine.

Conventionally, as a method of supplying lubricating oil to each sliding part such as the crankshaft and piston pin in this type of internal combustion engine, the lubricating oil in the oil sump in the crank chamber is supplied using an oil scraper provided on the lower end surface of the large end of the connecting rod. There is a so-called splash lubrication method in which the oil is scraped up to apply droplets of oil to each of the sliding parts.

However, in this splash lubrication method using an oil scraper, since the oil scraper swings in a large elliptical orbit, a relatively large rank chamber is required. Since it gives a relatively large impact, it is one of the causes of output loss.

Furthermore, this method has a problem in that the amount of splashed oil becomes insufficient when the lubricating oil level drops.

Furthermore, it is advantageous for the lubricating oil droplets to be made as fine as possible and mixed in the form of mist in the atmosphere for lubrication of areas where direct splashing cannot be applied (for example, the breather chamber communicating with the crankcase). However, in the conventional splash lubrication method, the lubricating oil droplets are not made sufficiently fine and it is difficult to lubricate a breather chamber or the like with an atmosphere containing atomized lubricating oil.

This invention was made in view of the above problems,
To propose a lubricating device for an internal combustion engine, in which a rotating member for scraping oil is provided in a crank chamber and rotated at high speed in conjunction with a crankshaft, and the rotating member scatters lubricating oil in the form of fine particles in the form of mist. It is aimed at.

Hereinafter, the present invention will be explained based on the embodiments shown in FIGS. 1 to 4. In FIGS. 1 to 3, reference numeral 1
is the cylinder, 2 is the piston, 3 is the connecting rod, 4 is the crankshaft, 6 is the valve camshaft, 8 is the crank chamber, 9 is the intake valve,
10 indicates an exhaust valve.

The camshaft 6 is driven by the crankshaft 4 via a crankshaft gear 5 and a camshaft gear 7.

An intake valve cam 14 and an exhaust valve cam 15 are formed on the camshaft 6, and each cam 14, 15 drives the intake valve 9 or the exhaust valve 10 to open via a push rod 16 or 17.

The intake valve 9 and the exhaust valve 10 are biased toward the cam 14.15 (in the valve closing direction) by a valve spring 33 or 34.

The valve springs 33 and 34 are housed in a breather chamber 12, and this breather chamber 12 communicates with the crank chamber 8 through a breather communication hole 11.

In the illustrated embodiment, a centrifugal weight 24 for a regulating bar is disposed in the lower part of the crankcase 8, and a camshaft gear 7
The centrifugal weight 24 is rotated at high speed by the speed increasing gear 20 that meshes with the centrifugal weight 24.

When the engine speed (crankshaft rotation speed) increases, centrifugal weight 2
4 expands outward and moves the firing control lever (or slot lever) 27 via the slider 26 in the direction of fuel reduction, which acts to suppress an increase in engine speed, resulting in a decrease in engine speed. Then it has the opposite effect.

The mounting height and the lubricating oil level are determined so that the lower half of the speed increasing gear 20 is always immersed in the lubricating oil.

The speed increasing gear 20 has a bowl-shaped casing 25,
A boss 28 formed at the center is fitted onto the centrifugal weight support shaft 21.

On the outer periphery of the bowl-shaped casing 25, there are many teeth 22, 22...
... is formed.

Some of the teeth 22, 22 of the speed increasing gear 20 have protrusions 23 extending in the longitudinal direction thereof.
are integrally formed.

A plurality of these protrusions 23 are formed at mutually axially symmetrical positions in consideration of rotational balance of the speed increasing gear.

The protrusion 23 has a cross-sectional shape and has an extending gear 23a, which is an extension of the teeth 22, and a bottom plate part 23b extending from the bottom of the extending gear 23a in the rotational direction and in the circumferential direction. There is.

That is, the protrusion 23 is designed to scoop up the lubricating oil at the L-shaped corner portion 23C and scatter the lubricating oil at high speed.

In this way, a large amount of lubricating oil can be continuously scraped up by the protrusion 23, so that the main bearing 36,
A sufficient amount of splashed oil can be obtained for each sliding portion such as the crank pin bearing 37 and the piston pin bearing 38.

Furthermore, since the protrusion 23 repeatedly plunges into and splashes against the lubricating oil surface at high speed, the droplets become very fine particles, become mist, and are easily mixed into the atmosphere within the crank chamber 8. It is possible to lubricate areas that are difficult to reach directly with splashes using so-called atmospheric lubrication.

For example, the suction and exhaust valve sliding parts 30 or the push rod sliding parts 31
Atmospheric lubrication is performed by the highly oil-rich atmosphere filling the breather chamber 12 through the ventilation hole 11.

This atmospheric lubrication prevents seizure of each sliding part without reducing its lubrication ability even when the lubricating oil level drops.

In other embodiments of the present invention, the oil scraping protrusion may be provided on a gear for driving an engine accessory other than the speed governor, or may be provided on a single dedicated gear.

Further, the oil scraping protrusion is not limited to the illustrated embodiment, and its size, shape, quantity, etc. can be set as appropriate.

Next, to explain the effect of the present invention, according to the lubricating device for an internal combustion engine of the present invention, a large amount of lubricating oil can be continuously scraped up and scattered in the form of mist using the oil scraping protrusion that rotates at high speed. Therefore, it is possible to obtain a sufficient amount of splashed oil for each sliding part, and since the splashed droplets themselves are very fine particles, sufficient atmospheric lubrication can be expected. Efficient lubrication can be performed even on lubricated parts that are difficult to break.

In addition, since the lubricating device of the present invention only needs to provide an appropriately sized protrusion on the side of a small-diameter gear, the capacity of the crank chamber can be reduced compared to the conventional splash lubrication system, and the engine This has practical effects such as being able to reduce the size and weight.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of an internal combustion engine equipped with a lubricating device according to an embodiment of the present invention, Fig. 2 is a sectional view taken along line II-II in Fig. 1, and Fig. 3 is a sectional view taken along line III-III in Fig. 1. , FIG. 4 shows an enlarged perspective view of the speed increasing gear used in the lubricating device shown in FIG. 1. 2...Piston, 3...Connecting rod, 4.
... Crankshaft, 5 ... Crankshaft gear, 6 ... Camshaft, 7 ... Camshaft gear,
8...Crank chamber, 9...Suction valve, 1
0...Exhaust valve, 15...Cam, 20.
... Speed-up gear, 22 ... Teeth, 23 ...
...Protrusion on the side of the speed increasing gear, L...Lubricating oil.

Claims (1)

[Scope of utility model registration request] A crankshaft gear 5 attached to the crankshaft 4 and a camshaft gear 7 attached to an intake/exhaust valve camshaft 6 are meshed, and the camshaft gear 7 and a speed governor are installed below the crankshaft 4. By meshing with a speed increasing gear 20 attached to an auxiliary shaft such as the centrifugal weight support shaft 21, the crankshaft 4 drives the camshaft 6 and the compound shaft, and the teeth of the speed increasing gear 20 22.22...
Lubrication of an internal combustion engine characterized by making some of the teeth extend in the longitudinal direction to form a protrusion 23, and further immersing the speed increasing gear 20 in lubricating oil in the crank chamber 8. Device.