JPH04246217A - Blow-by gas heating device for engine - Google Patents

Abstract

PURPOSE:To prevent faulty operation or complete stop of operation of a PCV valve due to dewing or icing of water and oil contents contained in blow-by gas. CONSTITUTION:A part of a reducing path 18 in which separators 22 are incorporated is closely fitted on the upper surface of an exhaust manifold 23 to increase temperature of blow-by gas in the reducing path 18 through warm air which passes through the exhaust manifold 23.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blow-by gas heating device used to prevent condensation and freezing of a PCV valve of an engine.

0002

BACKGROUND OF THE INVENTION Blow-by gas that passes through the gap between the cylinder and piston of an engine contains a large amount of non-flammable gas such as carbon monoxide and hydrocarbons. Therefore, PCV (Positive Crankcase V)
By providing a reduction device in the engine, blow-by gas is suppressed from being released into the outside air. Next, a conventional example of a PCV reduction device for an engine will be described with reference to the drawings.

FIG. 2 shows a conventional PCV reduction device for an engine, in which 1 represents a PCV valve and 2 represents a blow-by hose. The PCV valve 1 is provided on the blow-by hose 2. 3 is a cylinder head cover, 4 is an engine body, 5 is a carburetor, 6 is an exhaust manifold, 7 is an air cleaner, 8 is a hose, 9 is a 3-way, and 10 is an intake manifold.

The cylinder head cover 3 and the 3-way 9 are connected by a hose 8, and the 3-way 9 branches into a PCV valve 1 and an air cleaner (clean side) 7. Further, the PCV valve 1 is connected to an intake manifold 10, and the air cleaner 7 is connected to the intake manifold 10 via a carburetor 5.

[0005] Accordingly, depending on the operating state of the engine body 4, the blow-by gas taken out from the cylinder head cover 3 is transferred to the engine body 4 via the intake manifold 10 as shown in either (1) to (3) below. will be reduced to (1) Everything is sucked into the intake manifold 10 side. (2) The mixture with air is sucked into the intake manifold 10 by the three-way 9. (3) A portion is sucked into the intake manifold 10 and the other portion is sucked into the air cleaner 7 side, and then sucked into the intake manifold 10 side.

[0006] In FIG. 2, the white arrows represent the movement of only the air, the dashed arrows represent the movement of the mixture of air and blow-by gas, and the black arrows represent the movement of only the blow-by gas. There is.

By the way, when the engine's PCV reduction device is at a relatively low environmental temperature, such as when starting the engine in winter, the PCV valve may condense and freeze due to relatively large amounts of water and oil contained in the blow-by gas. Sometimes. In such a case, the PCV valve malfunctions or becomes inoperable, making it impossible to prevent blow-by gas from being released into the outside air. In addition, such dew condensation and freezing cause the accumulation of oil and sludge on the pipe wall of the blow-by hose, and also cause the problem that the PCV valve becomes easily clogged.

[0008]

SUMMARY OF THE INVENTION Therefore, the present invention provides a blow-by gas heating device for an engine that prevents a PCV valve from malfunctioning or becoming inoperable due to dew condensation or freezing of moisture contained in blow-by gas. The purpose is to provide.

[0009]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a reduction passage for reducing blow-by gas taken out from a cylinder head cover of an engine, and a reduction passage interposed in the middle of the reduction passage. The exhaust manifold includes a separator and an exhaust manifold, and a portion of the reduction passage where the separator is provided is in close contact with the exhaust manifold.

0010

[Operation] With the above configuration, when the exhaust manifold is at a relatively low temperature such as when starting the engine, the separator separates the moisture and oil contained in the blow-by gas in the reduction passage. Prevents moisture and oil from being introduced to the PCV valve.

On the other hand, while the engine is operating, the exhaust manifold heats the blow-by gas through the separator, thereby preventing moisture and oil contained in the blow-by gas from condensing and freezing. Conclusion・
Thaw frozen water and oil.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a blow-by gas heating device for an engine. 11 represents a blow-by hose, 12 represents a PCV valve, and the PCV valve 12 represents the blow-by hose 1.
1 is provided. The PCV valve 12 is for suppressing blow-by gas from being released into the outside air, and is elastically supported by a spring 13.

14 is an intake manifold, 15 is a cylinder head cover, 16 is an engine body, and 1
7 indicates 3 ways. This 3 way 17
and the cylinder head cover 15 are connected by a hose 18 forming a return passage, and from the 3-way 17 to the PCV
Valve 12 and air cleaner (clean side) 19
It is branched off via a hose 20. Further, while the PCV valve 12 is connected to the intake manifold 14,
Air cleaner 19 is connected to intake manifold 14 via carburetor 21.

The above-mentioned return passage is for returning the blow-by gas taken out from the cylinder head cover 15 of the engine to the engine body 16, and the hose 18,
20, a three-way 17, a PCV valve 12, an air cleaner 19, a carburetor 21, and an intake manifold 14.

When the intake manifold 14 side is in a lower negative pressure state than the cylinder head cover 15 side, P
CV valve 12 is opened. As a result, the blow-by gas flows into the intake manifold 14 side and is returned to the engine body 16.

On the other hand, when the cylinder head cover 15 side is in a high negative pressure state, the opening state of the PCV valve 12 is limited depending on this pressure. Therefore, the amount of blow-by gas flowing into the intake manifold 14 side described above is suppressed compared to when the cylinder head cover 15 side is in a low negative pressure state.

Reference numeral 22 denotes a separator, and the separator 22 is interposed in the hose 18, in other words, in the middle of the reduction passage. 23 is an exhaust manifold or an exhaust manifold pipe, and the part of the hose 18 where the separator 22 is provided is the exhaust manifold 2.
It is provided in close contact with the upper surface of 3.

A plurality of partition plates 24 are arranged inside the separator 22 in a direction that obstructs the flow of the blow-by gas through the hose 18, and allow moisture and oil contained in the blow-by gas to adhere to the partition plates 24. I'm making it easy.

In the engine blow-by gas heating device of the present invention constructed as described above, when the environmental temperature is relatively low such as in winter, the separator 22 removes water and oil contained in the blow-by gas in the reduction passage through the partition plate 24. Separate by. By preventing the separated moisture and oil from being introduced to the PCV valve 12, dew condensation of the moisture and oil can be prevented.

On the other hand, during engine operation, warm air is generated inside the exhaust manifold 23, so the temperature of the portion of the hose 18 where the separator 22 is provided rises, and the blow-by gas flows through the separator 22. It will get heated. Therefore, even if the blow-by gas is cooled by the outside air sucked into the air cleaner 19, it is possible to prevent moisture and oil contained in the blow-by gas from condensing or freezing. Furthermore, water and oil that have already dewdenned and frozen are thawed by the blow-by gas heated by warm air through the separator 22.

Furthermore, in order to increase the temperature of the blow-by gas, it is sufficient to simply provide the hose 18 in close contact with the exhaust manifold 23, and the installation of the hose 18 does not depend on the layout of each component. Furthermore, hose 1
The blow-by gas in 8 is the exhaust manifold 2.
Since the temperature is raised only by the warm air flowing through the chamber 3, there is no need to provide any special structure for raising the temperature.

[0022]

[Effects of the Invention] Since the present invention is constructed as described above, it is possible to increase the temperature of the blow-by gas in the reduction passage and prevent the accumulation of oil and sludge without providing any special construction. This prevents the PCV valve from malfunctioning or becoming inoperable, and does not result in an increase in cost for modification or design changes.

[Brief explanation of the drawing]

FIG. 1 is a front view showing essential parts of an embodiment of the present invention.

FIG. 2 is a front view of a conventional example.

[Explanation of symbols]

15 Cylinder head cover 16 Engine body 18 Reduction passage (hose) 22 Separator 23 Exhaust manifold

Claims (1)

[Claims] 1. A combustion engine comprising: a return passage for returning blow-by gas taken out from a cylinder head cover of an engine; a separator interposed in the middle of the return passage; and an exhaust manifold; 1. A blow-by gas heating device for an engine, characterized in that a portion provided with is in close contact with the exhaust manifold.