JPS645046Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an oil separator provided in a rock cover.

(Conventional technology) Blowby gas generated in the crankcase of an automobile engine contains gases that are harmful to the human body, so it is not released into the atmosphere, but is introduced from the rock cover into the intake manifold and returned to the engine where it is re-burned. There are many things. However, since the blow-by gas contains oil mist, if it is reburned as described above, the amount of oil consumed will increase, and the passage leading to the engine will be contaminated, resulting in malfunction. Therefore, an oil separator is installed inside the rock cover to collect the oil mist and return the oil to the engine. For such purposes, the Rocker Cover Breather disclosed in Japanese Utility Model Publication No. 57-171110 or Japanese Utility Model Publication No. 50-32685
There is an oil recovery device for an oil separator disclosed in No. The former has a labyrinth-shaped oil drainage passage provided in the rocker cover, an oil reservoir chamber provided at the outlet end thereof, and a return pipe communicating the bottom of the oil reservoir with the oil reservoir in the rocker chamber. Furthermore, an oil separator having a filter is provided downstream of the outlet, and the oil separated there is communicated with the engine oil pan.
In the latter case, steel wool is loaded into the casing to allow the blow-by gas to pass through and be sucked into the intake system, and the oil is separated by the steel wool and collected at the lower end of the casing.
This allows oil to flow out through small oil holes. Due to its surface tension and viscosity, oil will not flow out until the oil level reaches line A, which is higher than the oil hole, and will flow out once it reaches line A. However, the oil level is designed not to drop below line B, which is lower than line A.

(Problems to be Solved by the Invention) In the oil return means as described above, the former is a preliminary oil return means at a stage upstream of the oil separator provided outside the rock cover, and the oil separator is provided separately. Moreover, the length of the return pipe must be set in consideration of the oil level height of the oil reservoir in the rocker chamber, and the length cannot be determined freely. Further, if there is no oil reservoir in the rocker chamber, it is inconvenient that the gas cannot be prevented from flowing into the rocker chamber. In the latter case, the oil is separated by steel wool inside the casing;
Since the entire area under the steel wool in the casing is an oil reservoir and there is no pipe below, the oil level between level lines A and B increases and decreases compared to when the oil level increases and decreases in the pipe. It is slow. Therefore, since the time when the oil level remains low near line B is relatively long, when the suction force (negative pressure) in the intake system is relatively large, blow-by gas has a long opportunity to flow back through the oil hole. It turns out. Further, the operation for starting and stopping the oil from flowing out of the oil hole becomes inaccurate, which may impede the oil draining function.

(Means for Solving the Problems) In view of the above problems, the present invention provides an oil separator that ensures oil drainage and prevents blow-by gas from flowing in from the drain pipe.
An oil separation section consisting of a perforated plate and a filter member is provided inside the Rotsuka cover, which is partitioned by a shielding plate, and a drain pipe with an open lower end that hangs down from the bottom wall of the shielding plate is installed, and the lower end of the drain pipe is narrowed to form an oil film. The aperture opening is sized to form.

(Function) The blow-by gas enters the separation section from the inlet provided at the end of the shielding plate, and the oil is separated.The separated oil flows down to the drain pipe, but an oil film is formed at the throttle opening for a small amount of time. The oil is retained and does not drip. Therefore, no blow-by gas is inhaled. As the amount of oil increases, the weight of the oil ruptures the oil film and the oil drips until the amount retained above is reached.
There, the dripping stops due to the formation of an oil film. Separation of oil is reliably carried out inside the rock cover by a perforated plate and a filter member, and the separated oil is collected in the drain pipe, so the oil level rises and falls quickly in proportion to the amount of oil, so it can be easily removed from the throttle opening. The operation of oil flow and stop is reliable.

(Embodiment) As shown in FIG. 1, an oil separator 1 is built into a locking cover 10 attached to a cylinder head H, and a shielding plate 2 is fixedly installed inside the locking cover 10 above the oil separator 1. A blow-by gas inflow hole 3 provided at the end of the shielding plate 2
A blow-by gas passage 5 is formed between the blow-by gas outlet pipe 4 and the blow-by gas outlet pipe 4 which is installed above the rock cover. On the upstream side thereof, there is provided an oil separation section 6 consisting of a perforated plate 7 and a filter member 8 made of, for example, a spongy metal body. Furthermore, on the downstream side of the oil separation section 6, a drain pipe 11 is provided which extends from the bottom wall 9 of the shielding plate 2 toward the cylinder head H side and has a throttle opening 12 at its lower end.
As shown in FIGS. 1 to 3, the drain pipe 11 of this embodiment has a throttle opening 12 which is formed into an elongated opening by squeezing the lower end of the pipe from both sides, and a low part of the bottom wall 9 of the shielding plate 2. installed on. However, the opening at the lower open end is not limited to the shape of the aperture opening 12 described above.

Next, the operation of the oil separator with the above configuration will be explained.

Broker by gas generated in the crankcase (not shown) is introduced into the rocker cover 10 via the cylinder head H, and flows into the blowby gas passage 5 through the inlet port 3 of the oil separator 1 due to negative pressure on the intake manifold (not shown) side. The oil is separated into unburned gas and oil by an oil separation section 6 provided at The unburned gas is then sucked into the engine (not shown) through the outflow pipe 4 and re-burned, and the separated oil flows into the drain pipe 11 along the bottom wall 9 and is blown away by the surface tension of the oil. An oil film is formed in the elongated aperture 12 provided at the lower end.

Note that when the blow-by gas is sucked into the intake manifold side as described above, the opening area of the throttle port 12 is much smaller than that of the inflow hole 3, and the ventilation resistance is high, so even if the blow-by gas is tried to be sucked through the throttle port 12, an oil film will not be formed. Formed and blocked.

A slight pressure difference between the inside and outside of the shielding plate 2 prevents the oil film from being broken.

The separated oil is drained from the drain pipe 11.
, the oil level rises, and the elongated orifice 12
When the weight of the height of the oil whose base area is applied to the oil film exceeds the surface tension of the oil, the oil film ruptures and the oil drips from the throttle opening 12. In other words, the oil film due to the surface tension of the oil at the orifice 12 is balanced by a certain height h (shaded area within the two-dot chain line) of the oil whose bottom surface is the opening area of the orifice 12 shown in FIG. However, if more oil flows in, the balance will be broken and that oil will flow into the cylinder head H.
It drips to the side.

Also, on the oil surface inside the drain pipe 11,
Since a negative pressure that is slightly larger than the surface of the oil film at the orifice 12 is applied, the height of the balanced oil increases accordingly, but the differential pressure is small, and the maximum differential pressure causes the orifice to By optimizing the opening area and height of the drain pipe, the oil in the drain pipe will not be carried away to the intake manifold side.

(Effects of the invention) As described above, the present invention provides a drain pipe with an open bottom end hanging vertically at the bottom of the bottom wall of the shielding plate, and a throttle opening at the bottom end of the drain pipe narrowed to a size that allows oil film to form. As a result, a predetermined amount of oil is retained at the bottom of the drain pipe, and blow-by gas is not sucked from the drain pipe through the throttle opening. Make sure to drip the oil.
Therefore, it can exhibit excellent effects as an oil separator. Further, the oil accumulated at the bottom of the drain pipe is drained smoothly at any time, unlike the case where the oil drops all at once when the valve is opened against the closing force of the valve. Since the throttle opening is provided at the bottom end of the drain pipe, the oil level rises and falls quickly according to the amount of oil accumulated, so the operation of draining and stopping the oil at the throttle opening is performed reliably, and there is no risk of blow-by gas backflowing. The oil level will not remain stagnant for a long time in an unstable area. Furthermore, since the lower end of the drain pipe does not need to be immersed in a separate oil reservoir, the length can be freely determined in any case. Furthermore, the oil separator from the blow-by gas is completely separated from the blow-by gas only inside the rock cover because the perforated plate and filter member are installed inside the rock cover, so the oil separator has a simple structure and reliable oil separation and discharge operation. can be provided.

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view of the Rotsuka Kaba according to the present invention;
Figure 2 is a sectional view of the same, Figure 3 is the G of Figure 2.
It is an arrow view. 1... Oil separator, 2... Shielding plate, 3...
...Inflow hole, 4...Outflow pipe, 6...Oil separation section,
10...Rotsuka Kaba, 11...Drain pipe,
12...Aperture opening.

Claims (1)

[Scope of utility model registration request] A shielding plate that partitions the interior of the rocker cover is fixedly installed in the rocker cover, an inlet for blow-by gas is provided at one end of the shielding plate, an outlet pipe for the blow-by gas is provided on the upper wall of the rocker cover at the other end, and A perforated plate and a filter member are disposed between the inlet and the outlet pipe to form an oil separation section, and a drain pipe with an open bottom end is provided at the bottom of the shielding plate at the other end of the oil separation section. An oil separator in which the lower end of the pipe is narrowed to form a throttle opening, and the throttle opening is sized to form an oil film due to the surface tension of the oil and maintain a predetermined amount of oil.