JPH06317133A - Forced lubrication device for engine - Google Patents

Abstract

PURPOSE:To shorten the time required for warming up by heating lubricating oil which returns to an oil pans in a short time. CONSTITUTION:The oil pan 4 of an engine 1 is communicated with each lubricating portion 6a-6d by means of a lubricating oil passage 5 and a lubricating pump 12 and a relief valve 13 are interposed in the respective portions of the lubricating oil passage 5, and lubricating oil 10 in the oil pan 4 is forcibly fed to each lubricating portion 6a-6d by means of the lubricating pump 12. A relief oil passage 15 is formed which extends from the cylinder head 2 to the cylinder block 3 of the engine 1 and is communicated with the relief valve 13. At cold start of the engine 1 the lubricating oil 10 is returned into the oil pan 4 from the relief valve 13 via the relief oil passage 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forced lubrication system for an engine, and more particularly to a technique for raising the temperature of lubricating oil to a state where it can be operated and operated in a short time when the engine is cold started.

[0002]

2. Description of the Related Art As a forced lubrication system for an engine, the one shown in FIG. 3 has been known. That is, the oil pan 4 of the engine 1 is provided with a lubricating oil passage 5 for each lubricating portion 6a.
6d, the lubricating oil passage 5 is provided with a lubricating pump 12 and a relief valve 13, and the lubricating oil 1 in the oil pan 4
0 is configured to be pumped to each of the lubrication parts 6a to 6d by the lubrication pump 12, and when the set oil pressure is exceeded, the oil 10 is directly returned to the oil pan 4 via the relief valve 13.

[0003]

The above-mentioned conventional example has the following inconveniences. That is, at the cold start of the engine 1, the viscosity of the lubricating oil 10 is higher than that at the time of operation, and the pumping hydraulic pressure of the lubricating pump 12 exceeds the set hydraulic pressure of the relief valve 13. Therefore, a large amount of oil returns directly to the oil pan 4 via the relief valve 13. Therefore, the temperature of the lubricating oil 10 that has returned to the oil pan 4 does not immediately rise, and it takes a long time for warm-up operation. The present invention has been made in consideration of such circumstances, and an object thereof is to warm the lubricating oil 10 returning to the oil pan 4 in a short time to shorten the time for warm-up operation.

[0004]

In order to solve the above-mentioned problems, the means adopted by the present invention is such that the oil pan 4 of the engine 1 is communicated with each of the lubricating portions 6a to 6d by a lubricating oil passage 5 and A lubrication pump 12 and a relief valve 13 are provided in the passage 5, and the lubrication oil 10 in the oil pan 4 is fed to the lubrication pump 12
In the forced lubrication system for an engine, the lubricating oil 10 is configured to be pressure-fed to each of the lubricating portions 6a to 6d, and the lubricating oil 10 is returned into the oil pan 4 via the relief valve 13 when the set hydraulic pressure is exceeded. A relief oil passage 15 is formed from the cylinder head 2 to the cylinder block 3 of the engine 1, the relief oil passage 15 is communicated with the relief valve 13, and the lubricating oil 10 is fed through the relief oil passage 15 at the cold start of the engine 1. Oil pan 4
The gist is that it is configured to return to the inside.

[0005]

According to the present invention, the relief oil passage 15 is formed from the cylinder head 2 of the engine 1 to the cylinder block 3, and when the engine 1 is cold-started, the lubricating oil 10 is fed from the relief valve 13 to the relief oil. Return to the oil pan 4 via the path 15. At this time, the lubricating oil 10 becomes the cylinder head 2 and the cylinder block 3.
It absorbs the heat of and is warmed.

[0006]

Since the present invention is constructed and operates as described above, the lubricating oil 10 returning to the oil pan 4 can be warmed in a short time, so that the warm-up operation time can be shortened as compared with the prior art. It can be greatly shortened.

[0007]

Embodiments of the present invention will now be described in more detail with reference to the drawings. FIG. 1 is a schematic diagram of a forced lubrication device for a water-cooled diesel engine according to an embodiment of the present invention, and FIG. 2 is a vertical sectional view of the engine.

The forced lubrication system according to this embodiment is shown in FIGS.
As shown in FIG. 2, it has the same basic structure as the conventional example.
That is, in this forced lubrication device, the oil pan 4 of the water-cooled diesel engine 1 is communicated with the respective lubrication parts 6a to 6d through the lubrication oil passage 5, and the lubrication pump 12 and the relief valve 13 are interposed in the lubrication oil passage 5. Then, the lubricating oil 10 in the oil pan 4 is pumped by the lubricating pump 12 to the respective lubricating portions 6a to 6d, and when the set hydraulic pressure of the relief valve 13 is exceeded, the lubricating oil 10 passes from the relief valve 13 through the relief oil passage 15. The oil pan 4 is then returned to the inside. here,
Reference numeral 6a is a connecting rod lubrication portion, 6b is a tappet lubrication portion,
6c is a fuel injection cam lubrication part, 6d is a rocker arm lubrication part, 11 is an oil strainer, and 14 is an oil filter.

In this embodiment, the lubricating oil passage 5 is formed from the gear case 3a of the engine 1 and extends from the cylinder block 3 to the cylinder head 2. The relief oil passage 15 is formed from the rear wall 3b of the cylinder block 3 and extends from the cylinder head 2 to the side wall of the cylinder block 3. That is, the relief oil passage 15 has a rising oil passage portion 15a formed by rising from the rear wall 3b of the cylinder block 3, and the relief oil passage 15 shown in FIGS.
As shown in, the front and rear communication oil passage portions 15b running in the front and rear direction through the thick wall portion at the upper right corner of the cylinder head 2 and the branch oil passage portion 15c branched from the front and rear communication oil passage portions 15a into a plurality of branches.

The branched oil passage portion 15c is formed in each water jacket 2 of the cylinder head 2 and the cylinder block 3.
It is formed so as to extend to the outer side wall of W3W, and its open end is formed so as to face the inside of the crankcase 3c. Then, on the downstream side of the relief valve 13, the lubricating oil 10 is circulated in the relief oil passage 15 only when the engine 1 is cold-started, and when the lubricating oil 10 reaches the normal temperature during operation, the lubricating oil 10 is directly oiled. A flow path switching valve 16 for returning to the pan 4 is provided.

As a result, the lubricating oil 10 is supplied to the engine 1
At the time of cold start, the oil is returned from the relief valve 13 into the oil pan 4 via the relief oil passage 15. That is, at the cold start of the engine 1, the lubricating oil 10 absorbs the heat generated by the cylinder head 2 and the cylinder block 3 and is warmed up. As a result, the lubricating oil 10 returning to the oil pan 4 can be warmed in a short time, so that the time for warm-up operation can be significantly shortened as compared with the conventional technique.

The flow path switching valve 16 is for reliably switching the flow path by an oil temperature detector (not shown) and is useful for avoiding abnormal heating of the lubricating oil 10.
However, the flow passage switching valve 16 is not always necessary when configured as in the above embodiment. That is, the branched oil passage portion 15c is connected to the cylinder head 2 and the cylinder block 3.
This is because there is no possibility of abnormal heating even if a part of the lubricating oil 10 flows through the branched oil passage portion 15c during the operation operation by forming the water jackets 2W and 3W on the outer side walls.

The flow path switching valve 16 is not necessary even when the relief valve 13 is closed when the temperature of the lubricating oil 10 rises and drops to the normal hydraulic pressure during the operation. Absent. In this case, lubricating oil 10
Is the relief oil passage 15 only when the engine 1 is cold started.
This is because, in all other cases, the oil is circulated through the lubricating oil passage 5 and is pressure-fed to the lubricating portions 6a to 6d.

In the above embodiment, the water-cooled diesel engine is exemplified, but the invention is not limited to this.
The present invention can be applied to the case of an air-cooled engine. Particularly in the case of an air-cooled engine, the flow passage switching valve 16 reliably performs flow passage switching, and is useful for avoiding abnormal heating of the lubricating oil 10.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a forced lubrication device for a diesel engine according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a water-cooled diesel engine according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a forced lubrication device for a diesel engine according to a conventional example.

[Explanation of symbols]

1 ... Engine, 2 ... Cylinder head, 3 ... Cylinder block, 4 ... Oil pan, 5 ... Lubricating oil passage,
6a to 6d ... Lubricating part, 10 ... Lubricating oil,
12 ... Lubrication pump, 13 ... Relief valve, 15 ... Relief oil passage.

Claims (1)

[Claims] 1. An oil pan (4) of an engine (1) is connected to each of the lubricating parts (6a) to (6d) by a lubricating oil passage (5), and the lubricating oil passage is formed.
The lubrication pump (12) and the relief valve (13) are installed in (5), and the lubrication oil (10) in the oil pan (4) is applied to the lubrication pump (12) at each lubrication part (6a) to (6d). It is configured to be pumped to
In a forced lubrication system for an engine configured to return the lubricating oil (10) to the oil pan (4) via the relief valve (13) when the set hydraulic pressure is exceeded, the cylinder head (2) of the engine (1) is A relief oil passage (15) is formed over the cylinder block (3), the relief oil passage (15) is communicated with the relief valve (13), and the lubricating oil (10) is relieved when the engine (1) is cold-started. Oil passage
A forced lubrication system for an engine, characterized in that it is configured to return to the inside of the oil pan (4) via (15).