JPS5910721A - Lubricating device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To make a rush adjuster stable enough to operate and improve the lubricating efficiency of a lubricating part, by reducing the admixture of air bubbles in a way of dipping a cylindrical fence member surrounding a relief valve into oil in an oil pan. CONSTITUTION:Oil vigorously discharged out of a discharge hole 14 collides with the inner circumference of a cylindrical fence member 19 and thereby deenergized while deflected downward. Since a level of the lower end opening of the fence member 19 is set at depth H to an oil level LO, oil is in no case stirred up so strongly whereby the oil level is kept in a relative calm, smooth surface so that foaming to be produced by air mixing into the oil is reduced to the smallest possible extent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lubricating device for an internal combustion engine in which the oil discharged from a relief valve that releases the oil pump from a predetermined supply oil pressure or higher is subjected to G-rubbing so as not to contain air bubbles.

Internal Combustion Engine 1 In particular, in a four-cycle internal combustion engine, the oil collected in the sub-oil pan at the bottom of the engine is pumped to each lubricated part using an oil pump, and the lubricated oil is returned to the oil pan by gravity. There is also a σ) which circulates through each lubricated part.

In such an internal combustion engine, a human-shaped pump is used to some extent to supply the oil (h) required when the engine rotates at low speeds, but in this case, more than 100 ml of oil is supplied at medium and high speeds. In order to prevent this, when the pressure in the oil supply passage becomes higher than the set pressure, the relief valve installed in the oil supply passage leading from the oil pump to the engine slip is opened, and the oil in the oil supply passage is released. Return part of the oil pan to G.
[] in the oil supply path: This was to prevent the force from increasing.

Opening of this relief valve +r:? Since the pressure oil is vigorously injected in all directions from the relief boat of the relief valve, the oil in the oil pan is foamed by the flow of the same pressure oil, and the same pressure oil and the surrounding air or oil The oil in the pan gets caught up in the oil in the pan, causing many bubbles to form.

The air bubbles formed in the oil in the mail pan are not easily extinguished and are sucked into the oil pump G and supplied to the engine lubricating section, so that the pressure in the oil pump is 1. When the air θ4 is raised, some air θ4 is extinguished and noise is generated, which also prevents smooth supply of lubricating parts to each lubricating part, resulting in low lubrication performance. There was a slight inconvenience that the lash adjuster could not operate reliably when the mail was being supplied.

The present invention relates to an improvement of a lubricating device for an internal combustion engine that eliminates such inconveniences.
The object of the present invention is to provide a lubricating device that does not generate air bubbles in oil in an oil pan even when an IJ-F valve that releases oil pressure above a predetermined supply oil pressure of a pump operates.

An embodiment of the present invention illustrated in the drawings will be described below.

Reference numeral 1 denotes a four-cycle four-cylinder gasoline engine for a motorcycle, and a crankshaft 2 of the engine connects a piston and a connector/grod (not shown) that are slidably fitted to a spring (not shown). They are connected and are driven to rotate by the reciprocating motion of the biston.

The crankshaft 2 is rotatably supported by a hot crankcase 3 and a lower crankcase 4 which are divided into upper and lower halves, and an oil pan 5 can be freely fitted and removed from the F side of the lower crankcase 4. O Kosankai J is being kicked.

Further, an A-il pump 6 is disposed within the lower crankcase 4, and the rotating shaft (not shown) of the A-il pump 6 is connected to the crankshaft 2 via a chain transmission mechanism (not shown). cranknyaft 2
It is designed to be rotated in proportion to the rotational speed of.

Furthermore, a wire mesh oil filter 9 is installed in the suction hole 7 of the oil pump 6, and the discharge hole 8 of the synchronized oil pump 6 is connected to an oil filter 12 via a discharge pipe 10 and a communication passage 11. Oil is filtered in two stages using oil filters 9 and 12.

A relief valve 13 is provided in the communication passage 11, and the relief valve 13 includes a cylindrical valve body 15, which communicates with the communication passage 11 at one end and has a discharge hole 14 on the side thereof, and a valve body The plunger 16 is slidably fitted into the valve body 15, and the pin 17 is fitted into the valve body 15 so as to engage the plunger 16 in a fixed position. It consists of a compression coil spring 18 which is biased to close the discharge hole 14 by colliding with each other, and a cylindrical barrier part 19 which surrounds the outer periphery of the valve body 15 and extends to the lower end of the valve body 15. ing.

The discharge passage PO of the oil filter I2 is connected at one end to the lower crankcase 4 and the other end of the same oil passage 21 pivotally supports the crankshaft 2 via a communication passage 22. It is connected to a main journal (not shown), and the lower end of the oil passage 23 in the upper crankcase 3 is connected to the main journal.

Further, the upper end of the oil passage 23 is connected to a cam journal (not shown) of a rocker arm driving cam via piping and an oil passage (not shown).
It is connected to a rocker arm support oil EE T'Q ratunyu adjuster (not shown) via piping, a defoaming device, and an oil passage (not shown).

The illustrated embodiment is configured as described above, so that when the engine 1 is in operation, the crankshaft 2
When the oil pump 6 rotates, the oil pump 6 is rotated correspondingly, and the oil pump 6 and the lower crankcase 4 are rotated.
The stored oil is filtered by a wire mesh oil filter 9, then sucked into the oil pump 6 through the suction hole 7, pressurized by the same pump 6, and then passed through the discharge hole 8 to the old outlet pipe 10. and a mail filter via the communication path 11]
2, the oil is sent to the same oil filter 12 again:
6. :'j さし 7).

The oil filtered by the oil filter 12 is supplied to the main journal of the crankshaft 2 via the discharge passage 20, the widthwise oil passage 2I, and the communication passage 22, and the main journal is lubricated. The mail that has passed through the main journal is supplied to the cam journal of the rocker arm driving cam via the A-ile passage 23, piping and oil passages (not shown). It is supplied through a passage to a hydraulic ratchet adjuster for rocker arm support.

Furthermore, if the oil pressure in the communication passage 11 exceeds a predetermined value due to the oil passage from the discharge hole 8 of the auxiliary oil pump 6 to each of the above-mentioned lubricating parts being blocked by dirt or the like, the brake/jar 6 will be compressed. The oil in the communication passage 11 is pushed downward against the spring force of the coil spring 18, and the outlet hole 14 that was blocked by the plunger 16 is opened, and the oil in the communication passage 11 is discharged from the outlet hole 14 to the valve body 15 and the cylindrical barrier member. The oil is discharged into the oil pan 5 through the passage 19.

In this case, when the oil vigorously discharged from the discharge hole 14 collides with the inner circumferential surface of the cylindrical barrier member 19 and its force is reduced, it is deflected downward.

And the oil level of the oil stored in the oil tank 5 and lower crankcase 4.

The level L1 of the discharge hole 14 of the relief valve 13 is the oil level L. The depth of H6 is set for the cylindrical barrier member 1! ] Level L2 of the lower end opening
The oil level L is deeper than the level L1 of the discharge hole I-1. A depth G of H and a depth G are set for the depth H and the depth G'.

Conventionally, the oil level is L. Since I■-oil is forcefully discharged in the horizontal direction from the relief valve discharge hole 1/1 with a relatively shallow depth of H6, the lower crankcase 4
The oil in the oil pan 5 is strongly agitated, the surface of the oil is violently rippled, air is mixed into the oil, and air bubbles are formed.

However, in the embodiment of the present invention, the pressure oil forcefully discharged from the relief valve discharge hole 14 in the horizontal direction collides with the inner circumferential surface of the cylindrical barrier member 19 and is deenergized. Since it is deflected in one direction by the member 19, 1. The oil in the lower crankcase 4 and mail pan 5 is
Since the oil is not agitated as strongly as in the conventional oil, the oil level is kept relatively quiet and smooth, and air carving due to air in the oil is significantly reduced.

The relationship between the oil depth Ho and the air bubble inclusion rate for a conventional relief valve without a cylindrical barrier member 19 (=J Enciso) and this embodiment in which a relief valve of the same size as this is equipped with a cylindrical barrier member 10 is shown below. The experimental results are illustrated in FIG.

Curve A is a characteristic diagram of the conventional one, and curve B is a characteristic diagram of this embodiment. As the oil depth increases, the air bubble entrainment rate decreases.

Furthermore, in this embodiment, the cylindrical barrier member 19 is plunged deeply into the oil in the lower crankcase 4 and the oil pan 5, so that when the motorcycle suddenly accelerates or decelerates,
Even if the oil surface of the same oil is significantly tilted back and forth, the negative effects are less than with conventional oils.

This is because, as seen from curves A and B, in curve A, the air bubble inclusion rate changes significantly with changes in the oil level.
Not only due to the above-mentioned sudden acceleration/deceleration, but also when some fluctuation occurs in the front surface difference, the bubble inclusion rate increases rapidly. On the other hand, in the above-mentioned embodiment, it can be seen that when the absolute value of the bubble inclusion rate is low, the fluctuation rate is also small, and it is effective.

In this way, in this example, even if the relief valve 13 is provided, the incorporation of air bubbles in the oil is significantly suppressed, and each lubricating part of the engine 1 is sufficiently lubricated. Your adjuster can be made smoothly.

In the present invention, the predetermined supply Mll of the oil pump (the above is F
The remaining relief valve and the suction hole of the same oil pot are immersed in the oil stored in the same auxiliary oil pan having a set volume. , IJ IJ-] valves, the immersion depth of the relief valve into the oil pan is substantially increased by the barrier, and air bubble entrainment in the oil pan is reduced. Ru. For this reason, when the lash adjuster, which prevents air bubbles from entering, operates stably, the oil lubrication performance of each F4 sliding part of the engine improves, and no noise is generated due to the disappearance of air bubbles.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional side view showing an embodiment of a lubricating device for an internal combustion engine according to the present invention, and FIG. 2 is a characteristic diagram showing the difference in bubble inclusion rate between the conventional lubricating device and the embodiment. 1... Four-stroke, four-cylinder gasoline engine for motorcycles, 2... Crank 0 kunyaft, 3... Upper clan color case, 4... Lower crank case, 5...
Oil 4 yarns, 6...Oil pump, 7...Suction hole, 8...Discharge hole, 9...Wire mesh oil filter, 10...Discharge pipe, 11...>1' passage , 12...
Oil filter, 13... Relief valve, 14...
Discharge hole, 15... Valve body, 16... Plunger, 1
7... Bin, 18... Compression coil spring, 19
... Cylindrical barrier removal, 20... Discharge passage, 21... Mail passage, 22... Communication passage, 2:3... Oil passage. Agent: Patent attorney Nozomi Ehara (1 person)

Claims (1)

[Claims] In the lubricating system for an internal combustion engine, a relief valve for releasing a predetermined supply oil pressure or more of an oil pump and a suction hole in the oil supply path are immersed in oil stored in the same oil pan having a set volume. A lubricating device for an internal combustion engine, characterized in that the relief valve is surrounded by a barrier having an open end only below the relief valve.