JPS6337458Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The invention relates to a droplet lubricated overhead valve engine.
To provide a blazer device that can perform good oil separation and increase negative pressure in a crank chamber.

Further details of the field of application of the technology that is the premise of the present invention include, for example, Figure 1 or Figure 1.
As shown in Figure 0, a droplet lubricated overhead valve engine E
The crank chamber 1 and the rocker arm chamber 3 in the head cover 2 are connected in parallel through a gas outlet path 4 and an oil return path 5, and the rocker arm chamber 3 is connected to a blazer device 6.

<Prior art> As shown in FIG. 10, a conventional splash lubrication type engine has a gas outlet passage 4 at the left end of the bottom wall of the rocker arm chamber 3, and a blazer device 6 at the upper right end of the gas outlet passage 4.
An oil return path 5 which also serves as a push rod insertion hole is formed below the blazer device 6, and the outlet of the gas outlet path 4 is connected to the blazer hole 5 of the blazer device 6.
6.

<Problems to be solved by the invention> However, in the above configuration, the blow-by gas blown into the rocker arm chamber 3 directly enters the blazer device 6, so oil separation cannot be achieved sufficiently, and the blow-by gas is When the air is sucked into the air cleaner 60 from the blazer device 6, it can stain the cleaner element and cause clogging.

Therefore, in order to suppress the amount of blow-by gas entering, it may be possible to make the inlet of the blazer device smaller, but in this case, the negative pressure in the crank chamber 1 will be increased by reducing the breathing function of the blazer device. This results in the problem that it becomes impossible to prevent oil from seeping out of the crank chamber.

<Means for Solving the Problems> The present invention is intended to solve the above problems, and is proposed for the purpose of maintaining a large negative pressure in the crank chamber and improving the oil separation function of the Blazer device. To achieve this purpose, it is structured as follows.

That is, the communication hole 10 is branched out from the middle of the oil return path 5, and the Blazer device 6 is attached to the engine E, located above the branch point, and the oil return path 5 is connected to the oil return path 5 through the communication hole 10. By communicating with the rocker arm chamber 3, the blazer device 6 is connected to the downward oil return path 5 and the communication hole 1.
0 in order (the reference numerals are shown in FIGS. 1 and 2 as reference examples).

<Function> Therefore, the function of the present invention brought about by the above configuration will be described. The blow-by gas flowing into the rocker arm chamber 3 from the gas outlet path 4 once descends to the oil return path 5 and then ascends through the communication hole 10. At this time, the heavy oil is transferred to the oil return path 5.
The gas then descends into the crank chamber 1, and only the light gas smoothly enters the blazer device 6.

<Effects of the invention> Therefore, according to the invention, the oil in the blow-by gas quickly descends into the oil return path and does not rise toward the Blazer device, which improves the oil separation performance of the blow-by gas. can be made extremely large.

Therefore, even if blow-by gas is circulated to the air cleaner after oil is drained, the cleaner element will not be contaminated with oil.
Even if it is directly released into the atmosphere, it will not pollute the atmosphere.

Furthermore, since blow-by gas does not concentrate and flow directly into the inlet of the blazer device, the diameter of the inlet of the device can be widened, which increases the negative pressure in the crank chamber and prevents oil from seeping out. can be smoothly prevented.

<Example> Hereinafter, an example of the present invention will be described based on the drawings.

Fig. 1 is a longitudinal sectional front view of a droplet lubricated overhead valve engine, and Fig. 2 is an exploded plan view of the cylinder head and head cover of the engine. A cylinder 14 is provided in the center of the cylinder block 12, and a piston 16 interlocked with a crankshaft 15 is attached to the cylinder 14.
It fits inside so that it can slide up and down.

An oil scraping spoon 19 is connected to the large end 18 of the connecting rod 17 connected to the piston 16, and the spoon stirs the oil stored in the oil pan 20 provided below the cylinder block 11. is configured to allow splash lubrication.

Further, a bowl-shaped head cover 2 is removably fixed above the cylinder head 12, and a rocker arm chamber 3 is formed between the upper wall 21 of the cylinder head 12 and the head cover 2.
An intake/exhaust valve 22 is inserted into the left side of the valve 22 via a valve closing spring 23 so as to be movable forward and backward.
Intake/exhaust port 2 opened in cylinder head 12
Have them face exit 5.

Furthermore, two support bolts 27 of a knuckle-shaped pivot device 26 are provided on the right side of the cylinder head upper wall 21 in the front-rear direction, and a ship-shaped rocker arm 28 is pivoted to the pivot device 26 so as to be swingable left and right. Support the input end 29 of the rocker arm 28 to the push rod 30,
Further, the output ends 31 are configured to be able to come into contact with the stem ends 32 of the intake and exhaust valves 22, respectively.

The push rod 30 is loosely fitted into the oil return path 5 formed from the cylinder block 11 to the cylinder head 12, and its lower portion 33 is brought into contact with a valve drive camshaft 35 interlocked with the crankshaft 15 via a tappet 34.

Further, the upper part 36 of the push rod 30 is loosely fitted into the long groove 38 of the guide plate 37 attached to the upper end of the gear return path 5 to prevent the push rod 30 from shifting from the longitudinal direction of the locker arm 28 and swinging laterally. There is.

This guide plate 37 has a guide portion 39 made by cutting and raising parts of the plate upward and downward toward the left and right sides of the guide plate 37, and the guide length to the push rod 30 is made longer than before (conventionally, as shown in FIG. 8). (In this way, the plate was cut and raised in the same upward direction using one long groove), completely preventing the push rod 30 from swinging laterally.

In this case, as shown in FIG. 5, the guide plate 37 may be configured such that the guide portions 39a where the long grooves 38 are close to each other are directed downward, and the guide portions 39a which are far from each other are directed downward.
b may be cut upwards, or as shown in FIG.
A downwardly cut and raised guide plate 37 may be attached to the back side of a conventional guide plate.

When disassembling the inside of the cylinder block 11, in order to prevent the push rod 30 from falling off the guide plate 37 (conventionally, as shown in FIG. 9, the long groove 38 was made straight, the insertion hole at the tip 40
(There were many cases in which the push rod 30 fell off from the push rod), the long groove 38 was bent at a right angle, the push rod operating groove 41 was formed in the same direction as the length direction of the rocker arm 28, and a large diameter insertion groove was formed in the direction orthogonal to the push rod operating groove 41. A hole 40 is formed so that the push rod remains in the operating groove 41 even during disassembly (see FIG. 2).

Further, as shown in FIG. 7, the long groove may be bent at an acute angle less than a right angle.

On the other hand, the cylinder head upper wall 21 is formed to have a downward slope from the intake/exhaust valve 22 side toward the push rod 30 side, and the cylinder head upper wall 21
A peripheral wall 50 that stands up around the cylinder head 12 is formed in an inclined shape that falls laterally outward toward the top, and a flat box-shaped head cover 2 is attached to the peripheral wall 5 of the cylinder head 12 from above.
0 can be attached and detached freely.

Then, a gas outlet passage 4 is opened in the left side wall 45 extending to the cylinder block 11 and the cylinder head 12, and the lower end thereof is connected to the crank chamber 1.
The upper ends of the cylinder head upper wall 21 are opened in the left front part of the rocker arm chamber 3, that is, in the front part 46 of the side end surface of the exhaust valve 5, so that the blow-by gas blown from the combustion chamber 47 into the crank chamber 1 can be removed. After the oil is guided to the rocker arm chamber 3 through the lead-out path 4, the oil is separated by a Blazer device 6 provided on the right side of the rocker arm chamber 3.

The Blazer device 6 has an inflow chamber 52 formed by forming the upper part of the right peripheral wall 50a of the cylinder head, which is thick and slopes upward to the right and is located behind the upper part of the push rod 30, into a box shape. The inflow chamber 52 and the blazer chamber 53 are partitioned by a blazer plate 54, and a reed valve 55 is provided on the blazer chamber 53 side of the blazer plate 54.

Further, a communication hole 10 is formed along the right side circumferential wall 50a of the cylinder head in an upward-sloping shape to the right, and its inlet 10a is opened above the oil return passage 5, and its outlet 10b is opened into the inflow chamber 52. 52
A blazer hole 5 is provided in the center of the blazer plate 54 that seals the blazer hole 5.
6, a reed valve 55 is attached to close the blazer hole 56 to face the blazer chamber 53, and a gas outlet pipe 57 is opened from the blazer chamber 53.
is led out, and its outlet 58 is communicated with the clean air chamber of the air cleaner 60.

Therefore, the blazer device 6 is connected to the lock arm chamber 3.
As shown in FIG. 3, the inflow chamber 52 and the communication hole 10 of the Blazer device 6 can be connected to the fitting hole of the support bolt 27 of the rocker arm pivot device. If it is formed in the same upward-rightward slope as 27a, it can be easily cut out.

To explain the function of the splash-lubricated overhead valve engine thus constructed, the blow-by gas that has blown from the combustion chamber 47 into the crank chamber 1 flows into the rocker arm chamber 3 through the gas outlet passage 4, and then flows through the intake/exhaust valve 22. While the shaft, rocker arm 28, etc. are partially coated with oil, they are once lowered into the oil return path 5, and then enter the communication hole 10.

The blow-by gas that has flowed into the communication hole 10 rises obliquely upward and enters the inflow chamber 52 , passes through the blazer hole 56 , is separated from oil by the reed valve 55 , and then flows from the blazer chamber 52 through the gas outflow pipe 57 . The air is then circulated to the air cleaner 60.

At this time, the oil contained in the blow-by gas is separated from the gas when the blow-by gas descends to the oil return path 5 due to its weight, and further travels along the side wall of this return path 5 to the oil pan 20. As it descends, the light gas rises through the communication hole 10 and is again drained by the blazer device 6.

Therefore, even if a small amount of oil remains in the blow-by gas flowing into the blazer device, the oil is sufficiently separated by this blazer device, so that the oil content is less than that of the gas released through the gas outlet pipe 57. can be effectively eliminated.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional front view of a droplet lubrication type overhead valve engine;
Figure 2 is an exploded plan view of the cylinder head and head cover of the same engine, Figure 3 is a vertical sectional side view of the main parts around the oil return passage of the same engine, and Figure 4 is the main parts around the rocker arm chamber showing another embodiment. 5 is a vertical sectional front view of a guide plate showing a modification of the long groove cut and raised, FIG. 6 is a view corresponding to FIG. 3 showing another modification of the guide plate, and FIG. 7 is a diagram of the long groove. A perspective view of a guide plate showing a modified example of the shape, Fig. 8 is a view corresponding to Fig. 6 showing a conventional guide plate, Fig. 9 is a view corresponding to Fig. 7 also showing a conventional guide plate, and Fig. 10 is a blazer. FIG. 4 is a diagram corresponding to FIG. 4 showing a conventional example of the device. 1...Crank chamber, 2...Head cover, 3...
... Locker arm chamber, 4 ... Gas outlet path, 5 ... Oil return path, 6 ... Blazer device, 10 ... Communication hole.

Claims (1)

[Scope of utility model registration request] The crank chamber 1 of the droplet lubricated overhead valve engine E and the rocker arm chamber 3 in the head cover 2 are connected in parallel through a gas outlet passage 4 and an oil return passage 5, and the rocker arm chamber 3 is communicated with a Blazer device 6. In the splash-lubricated overhead valve engine, the communication hole 10 is branched out from the middle of the oil return path 5, and the blazer device 6 is attached to the engine E with the blazer device 6 located above the branch point. The spray lubrication overhead type is characterized in that the Blazer device 6 is connected to the rocker arm chamber 3 through the descending oil return path 5 and the communication hole 10 in this order. valve engine.