JPS6034735Y2 - Blow-by gas recirculation device for internal combustion engines - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a blow-by gas recirculation device (hereinafter also referred to as a PCV device) for an internal combustion engine (hereinafter also referred to as an engine) installed in a vehicle such as an automobile.

BACKGROUND ART In the crankcase of an engine, unforeseen air-fuel mixture, that is, blow-by gas, that has leaked from the cylinder side through the gap between the cylinder and the piston accumulates.

If this blow-by gas is discharged outside the engine, it may cause pollution, so it is normally returned to the engine's intake system and supplied to the engine cylinders along with fresh air, and the inside of the crankcase is ventilated with the fresh air.

By the way, a PCv valve is provided in the passage of blowby gas from the crankcase of the engine to the intake system to control the flow rate of the blowby gas based on the difference between the negative pressure of the intake system and the pressure inside the crankcase.

Conventionally, this PC■ valve 6 was attached to the outside of the rad cover 1 to the cylinder of the engine as shown in FIG.

Therefore, in cold weather, moisture in the blow-by gas freezes and adheres to the inside of the PCV valve 6, resulting in a problem in that the operation of the PCV valve 6 is inhibited.

Furthermore, conventional engines had the disadvantage that if the pressure inside the crankcase became abnormally high for some reason, the oil filler cap would fall off due to the pressure and be lost.

In FIG. 1, 2 is a carburetor, 3 is an intake manifold, 4 is a crankcase, 5 is an air cleaner, 7 is an intake valve, 8 is an injection port for blow-by gas into the intake manifold 3, 9 is an exhaust valve, 10 indicates the exhaust manifold.

Further, solid line arrows indicate the flow of blow-by gas, and dotted line arrows indicate the flow of fresh air.

The object of this invention is to provide a blow-by gas recirculation device for an internal combustion engine that prevents the PCV valve from freezing and the oil filler cap of the engine from falling off.

This invention will be explained below based on drawings showing embodiments.

Note that the same components as in FIG. 1 are given the same numbers.

In FIG. 2, an oil filler cap 14 is attached via a gasket 13 to a flange portion 12 provided on the rad cover 1 to the cylinder of the engine.

A hole 14a is provided in the center of the oil filler cap 14, and a grommet 15 is attached to the hole 14a.

6 indicates a PCV valve.

The PCV valve 6 includes a cylindrical casing 61 and a tapered portion 6.
2a and two coil springs 63
．． It consists of 64.

The casing 61 includes a large diameter portion 61a and a small diameter portion 61c connected to the large diameter portion 61a via a shoulder portion 61b.

A ring-shaped wedge 61d is provided in the small diameter portion 61c, and a ring-shaped groove portion 61e is provided between this wedge 61d and the shoulder portion 61b.

The lower end of the large diameter part 61a is an inlet 61f formed by an inwardly bent flange, and the small diameter part 61c
The upper end of the discharge port 61g is formed by an inwardly bent flange.

The valve element 62 is housed in the large diameter portion 61a of the casing 61, and a portion of its tapered portion 62a is inserted into the small diameter portion 61c of the casing 61.

A flange 62b is provided at the lower end of the valve element 62,
The aforementioned coil spring 63 is inserted between the flange 62b and the shoulder portion 61b of the casing 61.

Further, the aforementioned coil spring 64 is inserted into the small diameter portion 61c of the casing 61 above the valve element 62.

The PCV valve 6 is fitted into the grommet 15 through its groove 61e, and the large diameter portion 61a and valve element 62 protrude inward of the oil filler cap 14.

Further, one end of the blow-by gas hose 16 is inserted into the small diameter portion 61c of the PCV valve 6.

The other end of the hose 16 communicates with the intake manifold 3.

In the above configuration, the blow-by gas in the rad cover 1 to the cylinder enters the casing 61 from the suction port 61f of the PC valve 6, is discharged from the discharge port 61g, and is discharged from the hose 1.
6 and returns to the engine's intake manifold 3.

The PCV valve 6 operates in response to the difference between the negative pressure of the intake manifold 3 and the pressure of the blow-by gas in the cylinder cover 1, and controls the flow rate of the blow-by gas.

As mentioned above, this idea places the PCV valve back inward to the engine oil filler cap, and connects the oil filler cap to the blow pipe gas hose via the PCV valve, so the PCV remains stable even in cold weather.
The valve is exposed to the high temperature atmosphere inside the filler cap and has a high temperature, so moisture in the blow-by gas does not freeze on the PCV valve.

Therefore, the PCV valve can always perform its flow control function sufficiently regardless of the temperature, so even if the pressure inside the crankcase increases, the pressure is relieved and the oil filler cap is prevented from falling off.

Furthermore, even if the oil filler cap is removed or even if it falls off, it will not be lost due to the blow pie gas hose.

[Brief explanation of the drawing]

FIG. 1 shows an example of a conventional engine equipped with a PCV device. Figure 2 is a longitudinal sectional front view of one embodiment of this invention, and Figure 3 is a P
A longitudinal sectional front view of the CV valve is shown. 1... Rad cover to cylinder, 4...
Crank case, 6...PCV valve, 14.
...Oil filler cap.

Claims (1)

[Scope of utility model registration request] A blow-by gas recirculation device for an internal combustion engine that recirculates blow-by gas in the crankcase to the intake system via a PCV valve, the PCV valve being installed in an oil filler cap of the engine so as to protrude inward from the cap. is,
A blow-by gas recirculation device for an internal combustion engine, characterized in that an oil filler cap is connected to a blow-by gas hose via a PCV valve.