JP2572848Y2 - Oil supply device for overhead valve type oil cooled engine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil supply device for an overhead valve type oil-cooled engine in which an oil-cooling chamber is provided in an engine and oil absorbed in the oil-cooling chamber is radiated by an oil cooler. To provide a breather capable of maintaining high breather performance even if oil blows back or the like occurs.

[0002]

2. Description of the Related Art The basic structure of an oil replenishing device for an overhead valve type oil-cooled engine to which the present invention is applied is, as shown in FIG. 1 or 4, an overhead valve engine E is provided with an oil cooling chamber 1 and an oil cooler 2. The oil cooling chamber 1 communicates with the oil pan 6 of the engine E via the oil cooler 2 and the oil return path 5, and the oil absorbed in the oil cooling chamber 1 is radiated by the oil cooler 2 to release the oil from the oil return path 5. The oil supply port 8 and the breather device 10 are provided in the head cover 7 of the engine E, and the head cover chamber 11 is communicated with the oil pan 6 through the oil supply path 12 to return the oil to the oil supply port. The oil pan 6 can be supplied via the oil pan 8 and the oil supply path 12.

As a prior art of this type, as shown in FIG. 4, an auxiliary combustion chamber 1 of a vertical overhead valve diesel engine E is used.
An oil cooling chamber 1 is formed around the cylinder 9, the sub-combustion chamber 19 heated to a high temperature is cooled strongly with oil, and an oil supply port 8 is opened in the upper wall 35 of the head cover 7, and the cylinder head 18 and the cylinder 20 are cooled. A push rod hole penetrating the push rod hole 12 is formed as an oil supply path 12, and an oil return path 5 is vertically penetrated in a wall 21 protruding from the center of the push rod hole 12.

[0004] The oil cooling device of the engine E is configured as follows (see FIG. 3). That is, the oil cooler 2 arranged above the front part of the engine E faces the lower cooling fan 46, and the oil cooler 2 can be cooled by the cooling air of the cooling fan 46, and the forced lubrication device 22 of the engine E A relief valve 25 is provided in the lubricating oil passage 24 on the discharge side of the interposed lubricating pump 23 to supply the lubricating oil in the oil pan 6 to the lubricating pump 2.
3, the oil is pressure-fed to each lubricating portion 26 of the engine E, and surplus oil relieved from the relief valve 25 is sent to the oil cooling chamber 1 to oil-cool the sub-combustion chamber 19. It is configured to reflux.

[0005]

In the above prior art, since a tappet is inserted into the bottom of the push rod hole 12 serving as an oil supply path, the bottom of the oil supply path 12 is formed at the side of the tappet insertion opening. And opens into the crank chamber 27 through a narrow passage provided in the crank chamber 27. Therefore, when oil is supplied from the supply port 8 to the oil pan 6 via the supply path 12 while the operation is stopped, it is difficult to pour a large amount of oil at a time.

Therefore, it is conceivable to increase the bottom of the push rod hole 12 to facilitate oil injection.
During operation of the engine E, the push rod hole 12 serves as a flow passage for guiding blow-by gas blown from the combustion chamber into the crank chamber to the breather device 10 provided in the head cover chamber 11. For this reason, if the push rod hole 12 is enlarged, the blow-by gas will easily pass through, and the oil guided to the breather device 10 will be excessive, and the breather performance may be reduced. The present invention
It is a technical task to quickly supply oil and maintain high breather performance.

[0007]

Means for achieving the above object will be described below with reference to FIGS. 1 to 3 showing an embodiment. That is, according to the present invention, in the oil supply device of the overhead valve type oil-cooled engine having the basic structure, the oil return path 5 communicates with the head cover chamber 11 via the supply oil path 14. The distal end portion 15 is opened lower than the breather port 13 of the breather device 10, a shielding wall 16 projects from the head cover 7 into the head cover chamber 11, and the shielding wall 16 is positioned near the distal end portion 15 of the supply oil passage 14. The shield wall 16 is arranged so as to face the breather device 10 from the front end portion 15 of the supply oil passage 14.

[0008] The oil-cooled engine is a part of the engine body.
(For example, a sub-combustion chamber of a diesel engine, etc.), or one that is entirely oil-cooled. In the partial oil-cooled engine,
The portions other than the oil cooling portion are air-cooled, for example. In this case, the oil cooler 2 of the partial oil-cooled engine is cooled by an air cooling fan or the like.

[0009]

Since the supply oil passage 14 faces the head cover chamber 11, oil is supplied from the supply port 8 to the head cover chamber 11.
The oil is supplied to the oil pan 6 from the oil supply path 12 (for example, a push rod hole), and is also supplied to the oil pan 6 from the oil return path 5 via the supply oil supply path 14. In this case, the supply oil passage 14
Of the breather device 10
Since the opening is lower, the oil level during replenishment does not rise to the breather port 13, and no oil enters the breather device 10.

On the other hand, during operation of the oil-cooled engine E, the oil radiated by the oil cooler 2 is always returned from the oil return path 5 to the oil pan 6, so that blow-by gas rarely blows through the oil return path 5. Absent. But,
Since the oil return path 5 is communicated with the head cover chamber 11 via the supply oil path 14, the return oil from the oil cooler 2 is returned (that is, the oil is pumped back by the lubrication pump of the lubrication device). However, there is a possibility that the air may blow up into the head cover chamber 11 via the supply oil passage 14. However, since a shielding wall 16 protruding from the head cover 7 faces the front end portion 15 of the replenishing oil passage 14, the return oil is blown out by the shielding wall 16, and the return oil is changed from the oil supply path 12 to the oil pan 6. As a result of the reflux, it does not enter the breather device 10 straight.

[0011]

[Effects of the Invention] (1) Oil is simultaneously supplied from the oil supply path and the oil return path via the supply oil supply path. Therefore, a large amount of oil can be replenished at a time by increasing the replenishing amount per unit time (that is, the replenishing time of the oil can be shortened), so that the replenishing operation can be sped up. (2) Since the shield wall faces the tip of the supply oil passage, even if the return oil from the oil cooler is blown up in the head cover chamber through the oil passage, the oil is applied to the breather device by the shield wall. Since it can be prevented from entering, the breather performance can be kept high.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 is a vertical rear view of a main part of an oil replenishing device of a vertical overhead valve type partially oil-cooled diesel engine, FIG. 2 is a vertical rear view of a main part of an oil return path of the engine, and FIG. 3 is a main part of a cylinder of the engine. It is a top view.

As shown in FIGS. 1 and 3, a cooling fan 46 is mounted on a crankshaft 47 at a lower front portion of the vertical overhead valve diesel engine E, and an oil cooler 2 is provided at a front upper portion of the engine E. The oil cooler 2 can be cooled by the cooling air from the cooling fan 46. As shown in FIG. 1, the cylinder head 18 and the head cover 7 are assembled above the cylinder 20 of the diesel engine E, and the oil pan 6 is assembled below the crankcase 34.

As shown in FIGS. 1 and 2, a sub-combustion chamber 19 is provided in the cylinder head 18 and an oil cooling chamber 1 is formed in the outer peripheral wall of the sub-combustion chamber 15, and a cylinder 20 and a cylinder head of the engine E are provided. The oil supply passage 28 and the oil return 5 are provided through the oil passage 18. The outlet 28b of the oil supply passage 28 communicates with the oil cooling chamber 1, the oil cooling chamber 1 communicates with the inlet 3 of the oil cooler 2 via the inlet pipe 29, and the outlet 4 of the oil cooler 2
Through the outlet pipe 30 to the oil return path 5. FIG.
As shown in FIG.
A relief valve 25 is provided in the lubricating oil passage 24 on the discharge side of the lubricating pump 23 interposed in 2, and a relief oil passage 31 derived from the relief valve 25 communicates with an inlet 28 a of the oil supply passage 28.

As shown in FIG. 2, a first oil passage 32a is opened downward from the bottom 5a of the oil return passage 5, and a second oil passage 32b is opened from the bottom 5a to the right crank chamber 27. The third oil passage 32c is opened from the bottom 5a to the bag-like space 33 on the left side. Incidentally, the second and third oil passages 32b
32c can be easily formed because it is machined straight from the mounting hole 36 of the fuel injection pump 35 opened in the crankcase 34 (see the dashed line in FIG. 2). still,
Since the bag-shaped space 33 is opened to the crank chamber 27 at the end surface 44 (see FIG. 3) of the crankcase 34 to which the back cover is attached, oil flows from the third oil passage 32c to the bag-shaped space 3.
3 flows out to the crank chamber 27.

As described above, the lubricating oil pumped by the lubricating pump 23 of the diesel engine E is supplied to the crankshaft,
Lubricate each lubrication section 26 such as the camshaft and rocker arm.
The lubricating oil released from the relief valve 25 is
The oil is returned from the crank chamber 27 to the oil pan 6 via the oil supply path 28 → the oil cooling chamber 1 → the oil cooler 2 → the oil return path 5. During this time, the relief oil is cooled by the oil cooler 2 after the sub-combustion chamber 19 is strongly cooled by oil.

On the other hand, as shown in FIG. 1, the cylinder 20 and the cylinder head 18 of the vertical diesel engine E
The head cover chamber 11 is provided with a push rod hole 20, and a valve operating mechanism (not shown) such as a rocker arm is provided in the head cover chamber 11, and the valve operating mechanism can be driven by a push rod inserted into the push rod hole 20. A boss-shaped oil supply port 8 is provided on the upper wall 35 of the head cover 7, a closing plug 36 is removably screwed into the oil supply port 8, and the breather device 10 is mounted on the upper corner 37 of the head cover 7. Provide. Incidentally, oil is supplied to the oil pan 6 from the oil reinforcing port 8 through the head cover chamber 11 while the engine E is stopped.

As shown in FIG. 1, the breather device 10
Is composed of a breather chamber 39 partitioned by a breather plate 38, a breather port 13 opened in the breather plate 38, a reed valve 40 facing the breather port 13, and a breather outlet 41 opened in the breather chamber 39. In addition, breather exit 4
Numeral 1 communicates with the intake system of the engine E via the return path 42. The bottom of the push rod hole 12 communicates with the crank chamber 27 through an oil passage (not shown) formed in a side portion of the tappet fitting opening or the like. Connect to 6. The push rod hole 12 is configured as an oil supply path as described later.

The blow-by gas blown from the combustion chamber into the crank chamber 27 enters the breather device 10 through the push rod hole 12 and the head cover chamber 11, and the reed valve 40
The oil is separated and returned to the intake system from the recirculation passage 42. As shown in FIG. 3, the oil return path 5 extends vertically through the wall 21 protruding into the push rod hole 12, and the oil supply path 2 is provided on the right side of the cylinder bore 43.
8. The oil return path 5 and the oil supply path 12 are arranged.

As shown in FIG. 1, the upper end of the oil return passage 5 is connected to the head cover chamber 11 through a supply oil passage 14.
Communicate with An oil passage pipe 14a constituting a part of the supply oil passage 14 is arranged along the side wall 45 of the head cover 7, and the front end opening 15 is formed in the stepped portion 3 of the upper wall of the head cover 7.
It is opened close to 5a. The distal end portion 15 of the oil passage pipe 14a is opened lower than the breather port 13 of the breather device 10, and a shielding wall 16 protrudes downward from the head cover 7 into the head cover chamber 11.
6 is positioned near the tip end 15 of the supply oil passage 14, and the shielding wall 16 is arranged in a direction facing the breather device 10 from the tip end 15 of the supply oil passage 14 (that is, in plan view). The tip 15 of the supply oil passage 14 and the breather port 13 of the breather device 10 are arranged linearly with the shielding wall 16 at the center. However, the lower end portion 17 of the shielding wall 16 is disposed lower than the tip end portion 15 of the supply oil passage 14.

Therefore, the function of the oil supply device of the present embodiment will be described. Since the supply oil passage 14 faces the head cover chamber 11, when oil is supplied to the head cover chamber 11 from the supply port 8, the oil is supplied to the oil pan 6 from the oil supply path 12 (that is, the push rod hole). At the same time, oil is supplied from the oil return path 5 to the oil pan 6 via the supply oil passage 14 (the flow of oil supply is indicated by white arrows in FIGS. 1 and 2). Moreover, as shown in FIG. 2, the bottom 5a of the oil return path 5 has three oil passages 3
The oil flows smoothly into the crank chamber 17 because it communicates with the crank chamber 27 at 2a, b, and c. As a result, the amount of replenishment per unit time increases, so that a large amount of oil can be replenished at once and the replenishment operation can be sped up. Since the tip 15 of the supply oil passage 14 is opened lower than the breather port 13, the oil level being supplied does not rise to the breather port 13, and no oil enters the breather device 10.

On the other hand, during operation of the oil-cooled engine E, the oil radiated by the oil cooler 2 is always returned from the oil return path 5 to the oil pan 6, so that blow-by gas does not blow through the oil return path 5. rare. However, since the oil return path 5 is communicated with the head cover chamber 11 by the supply oil path 14, the return oil from the oil cooler 2 (that is, because this oil is pressure-fed back by the lubrication pump 23), There is a possibility that the oil will blow up to the head cover chamber 11 via the oil passage 14, but since the shielding wall 16 faces the front end portion 15 of the supply oil passage 14, the direction of the return oil is changed by the shielding wall 16. Thus, the oil is quickly returned from the oil supply path 12 to the oil pan 6.
Therefore, the oil is prevented from entering the breather device 10, and the breather performance is kept high.

Incidentally, in the present invention, the oil cooling chamber 1 is
And at least one of the cylinder head 18. The present invention is applicable not only to diesel engines but also to spark ignition engines.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional rear view of a main part of an oil replenishing device of a vertical overhead valve type partially oil-cooled diesel engine.

FIG. 2 is a vertical sectional rear view of a main part of an oil return path of the engine.

FIG. 3 is a plan view of a main part of a cylinder of the engine.

FIG. 4 is an equivalent view of FIG. 1 showing a conventional technique.

[Explanation of symbols]

1: oil cooling chamber, 2: oil cooler, 5: oil return path, 6
... oil pan, 7 ... head cover, 8 ... oil supply port,
DESCRIPTION OF SYMBOLS 10 ... Breather device, 11 ... Head cover room, 12 ... Oil supply path, 13 ... 10 Breather port, 14 ... Supply oil passage, 15 ... 14 tip part, 16 ... Shield wall, E ... Overhead valve type oil cooling engine.

Claims (1)

(57) [Scope of request for utility model registration] An oil cooling chamber (1) and an oil cooler (2) are provided in an overhead valve engine (E), and the oil cooling chamber (1) is connected to an oil cooler (2).
And an oil pan (6) of the engine (E) through an oil return path (5), and radiates oil absorbed in the oil cooling chamber (1) by an oil cooler (2) to an oil return path (5). From oil pan
(6), and an oil supply port (8) and a breather device (10) are provided in the head cover (7) of the engine (E), and oil is supplied from the head cover chamber (11) to the oil pan (6). Communicating via road (12),
In an oil supply device of an overhead valve type oil-cooled engine configured to be able to supply oil to an oil pan (6) via an oil supply port (8) and an oil supply path (12), an oil return path (5) is connected to a head cover chamber. (11) through a supply oil passage (14), and a tip of the supply oil passage (14).
(15) is opened lower than the breather port (13) of the breather device (10), and a shielding wall is inserted from the head cover (7) into the head cover chamber (11).
(16) and project the shielding wall (16) to the supply oil passage.
Close to the tip (15) of (14) and supply oil through
An oil replenishing device for an overhead valve type oil-cooled engine, wherein a shielding wall (16) is arranged in a direction facing the breather device (10) from a tip portion (15) of the (14).