JPH0681624A - Engine air cleaner hose with shield-type crankcase emission control system - Google Patents

Abstract

PURPOSE:To provide a means for economizing the consumption of engine oil as well as preventing the generation of an ill condition such as overrunning in an engine when intake negative pressure is increased due to the clogging or the like of an air cleaner during the operation of the engine to cause the collapse of an air cleaner hose. CONSTITUTION:An air cleaner hose 3 connected to the lower reaches of an air cleaner 2 has a shield type crankcase emission control system provided with a blow-by gas intake 8, and the downstream part 3b of the blow-by gas intake 8 is provided with a part lower in rigidity than the upstream part 3a of the blow-by gas intake 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine air cleaner hose having a shield type blow-by gas returning device.

[0002]

2. Description of the Related Art Unlike other open-type and close-type blow-by gas reducing devices, shield-type blow-by gas reducing devices are not provided with a PCV valve, and are simply connected to a crankcase and an air cleaner or other intake passage. Ventilating the inside of the crankcase.

In the above, P is provided in the blow-by gas returning passage which connects the crankcase and the intake manifold.
When the CV valve is arranged, when the negative pressure in the intake passage becomes large at the time of idling, the passage is throttled by the action of the PCV valve to control the reduction amount of blow-by gas.
Also, the action of the PCV valve prevents the oil in the crankcase from being taken away due to excessive negative pressure. However, in the shield type blowby gas reduction device,
Such control is not performed because there is no PCV valve.

FIG. 5 shows an example of an engine part to which a diesel engine having a conventional shield type blow-by gas returning device is attached.
(A) is an external perspective view thereof, and FIG. 5 (b) is H of FIG. 5 (a).
FIG. In the figure, 1 is an air intake duct, 2 is an air cleaner, 3 is an air cleaner hose, 4 is a surge tank, 5 is an intake manifold, 6 is an engine head cover, 7 is a blowby gas recirculation passage, and 8 is a blowby gas intake. Inlet 10 is an engine. Further, 3a shown in FIG. 5 (b) is a portion of the air cleaner hose 3 upstream of the blow-by gas intake port 3 and
“B” indicates a portion downstream of the blow-by gas intake port 8.

As shown in the figure, in the blow-by gas reducing apparatus, blow-by gas G discharged from the engine head cover 6 passes through the blow-by gas recirculation passage 7 and enters into the air cleaner hose 3 from the blow-by gas inlet 8 where the air cleaner 2 is discharged. It merges with the passing air flow A, enters the surge tank 4, and then the engine 10 from the intake manifold 5.
Is returned to the combustion chamber. The shield-type blow-by gas returning device has an advantage that the blow-by gas returning passage can be set shorter even when the engine body and the air cleaner are separated from each other due to the layout of the engine room, compared to the type in which the blow-by gas returning passage communicates with the air cleaner. There is.

[0006]

In the engine having the above shield type blow-by gas returning device, when the air cleaner 2 becomes clogged, the negative pressure of the intake air increases, which causes the air cleaner hose 3 to be crushed. Sometimes. At this time, as shown in FIG. 5 (b), the blow-by gas G also flows into the air cleaner hose 3 outside the intake air A, so that the blow-by gas G is blown into the air cleaner hose 3b on the downstream side of the blow-by gas intake 8. The negative pressure becomes higher in the air cleaner hose 3a on the upstream side of the intake port 8 where only the air is sucked from the air cleaner, and therefore, when this crush occurs, the air cleaner on the upstream side of the blow-by gas intake port 8 is required. It occurs on the hose 3a side.

When the air cleaner hose 3a is crushed as described above, the blow-by gas in the blow-by gas recirculation passage 7 is sucked out by the intake action in the intake stroke of the engine, and a large amount is blown from the blow-by gas inlet 8 into the air cleaner hose 8. The amount of blow-by gas sucked into the intake manifold 5 may rapidly increase, and a large amount of engine oil contained in the blow-by gas may flow into the combustion chamber of the engine to induce engine overrun. In addition, it causes troubles such as increase in engine oil consumption.

In view of the above circumstances, in the present invention, even if the intake negative pressure increases due to the clogging of the air cleaner during operation and the air cleaner hose is crushed, the engine does not have a problem such as overrun. And it aims at providing the means which can save the consumption of engine oil.

[0009]

In order to achieve the above object, the present invention has a shield type blow-by gas reducing device in which a blow-by gas intake is provided in an air cleaner hose connected to the downstream side of an air cleaner. Provided is an air cleaner hose for an engine, wherein an air cleaner hose having a portion having lower rigidity than a portion upstream of the blow-by gas inlet is provided at a portion downstream of the blow-by gas inlet. Further, it is convenient to form the low rigidity portion by an elastic member.

[0010]

[Operation] If the air cleaner is clogged while the engine is running,
When the negative pressure of intake air in the air cleaner hose increases, and the negative pressure becomes higher than a predetermined pressure, the air cleaner hose in a low rigidity portion downstream of the position of the blow-by gas intake of the air cleaner hose collapses. This allows
Even if the air cleaner hose is crushed, the crushed part is on the downstream side of the position of the blow-by gas intake, so engine oil does not spill out from the blow-by gas intake as in the past and engine overrun etc. Inconveniences are prevented and wasteful consumption of engine oil is saved.

[0011]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an air cleaner hose 3 according to a first embodiment of the present invention. FIG. 1 (a) is a perspective view of the hose 3 attached to an air cleaner 2 and a surge tank 4, FIG. 1 (b).
FIG. 3 is a sectional view of the air cleaner hose 3 shown in FIG.

As shown in the figure, the air cleaner hose 3 is composed of portions 31 and 33 having a corrugated cross section and a portion 32 having a smooth cross section and a thinner thickness than the former. Is open at a predetermined position in the corrugated portion 31 located on the upstream side of the air cleaner hose 3. Therefore, the portion 3a upstream of the blow-by gas intake 8 is entirely corrugated.
The downstream portion 3b that is a part of the blow-by gas intake port 8 and is composed of the remaining portion of the corrugated portion 31, the smooth cross-sectional portion 32, and the corrugated portion 33 located further downstream thereof. There is. With this configuration,
The corrugated portions 31 and 33 have high rigidity, and the strong smooth portion 32 has lower rigidity and weaker than that. Therefore, when the air cleaner 2 is clogged, the smooth-shaped portion 32 of low rigidity in the downstream portion 3b of the blow-by gas intake 8 is not crushed as in the conventional case, but is crushed. This serves as an intake shutter that closes the intake pipe, and prevents oil from being blown into the intake pipe from the blow-by gas intake port 8.

FIG. 2 shows a sectional view of the air cleaner hose 3 according to the second embodiment. In this case, the shape of the air cleaner hose 3 is the corrugated portions 31, 33 of FIG.
Instead of, the thickened portion of the cylindrical hose 31,
33, which has a high rigidity, and the intake shutter portion 32 has a thinner wall thickness than the thicker wall portions 31 and 33, has a low rigidity, and this portion is crushed first.

FIG. 3 shows a third embodiment. In this case, the length of the intake shutter 32 is shortened to form a groove-shaped line having a thin wall thickness. FIG. 3 (b) shows a perspective view when the air cleaner hose 3 is curved downstream of the blow-by gas intake port 8. In this case, the curved portion as shown in the drawing is generally easy to be crushed, and a groove-shaped line is further added. If it is provided and the wall thickness is reduced, this portion is more likely to be crushed.

In the first to third embodiments, the material of the air cleaner hose 3 is uniform and the same in each part, but only the shape is different. In the fourth embodiment shown in FIG. 4, the air cleaner hose 3 is different. Has the same cylindrical shape as each part, but the material of the intake shutter 32 has a lower rigidity than the other parts. Therefore, when crushing, the part of the intake shutter 32 should be crushed first. There is. Further, if the intake shutter 32 is formed of an elastic member, it can be restored even if this portion is temporarily crushed, so that this portion will not be damaged.

As described above, the portion of the intake shutter 32, which has low rigidity and is easily crushed, is connected to the blow-by gas intake port 8.
Since the upstream side of the blow-by gas inlet 8 is conventionally crushed when the air cleaner 2 is clogged by providing the blow-by gas inlet according to the above-described embodiment of the present invention, the blow-by gas inlet must be provided at a position downstream of the position. It will be crushed downstream of 8.

Thus, the air cleaner hose is prevented from being crushed upstream of the conventional blow-by gas intake port. Therefore, a large amount of oil is blown out from the intake port 8 into the air cleaner hose 3 together with the blow-by gas, which is the combustion chamber of the engine. It is possible to prevent the engine from overrunning due to inflow into the engine. Further, it is possible to suppress wasteful consumption of oil in the engine.

Therefore, the present invention has an effect of avoiding an increase in the engine speed by generating a crush in the blow-by gas intake port of the air cleaner hose. Needs repair and replacement.

However, in the fourth embodiment, when the intake shutter 32 is made of a material having rigidity lower than that of the other portions but having elastic properties, the inner diameter of the intake shutter 32 is reduced instead of being crushed. It is possible within a certain range to deal with the suction effect due to the clogging of the air cleaner by temporarily elastically shrinking the engine, which causes the driver to notice the engine malfunction and stop the engine, and to prevent the clogging of the air cleaner. If maintenance is carried out, the portion of the intake shutter 32 is elastically restored, so it is possible to continue to use it without replacement and repair. Further, by using the intake shutter 32 made of the elastic material, it is possible to detect an increase in intake negative pressure due to clogging of the air cleaner and the like at an early stage.

[0020]

According to the present invention, a large amount of oil is not blown out together with blow-by gas due to the clogging of the air cleaner in the air cleaner hose of the engine having the shield type blow-by gas reducing device, and thereby the engine overrun is caused. Is suppressed. In addition, the above saves wasteful consumption of engine oil.

[Brief description of drawings]

1 shows an air cleaner hose having a corrugated shape and a smooth shape in cross section according to a first embodiment of the present invention, FIG. 1 (a) is an external view showing its attached state, and FIG. 1 (b) is the air cleaner hose. FIG.

FIG. 2 is a cross-sectional view of an air cleaner hose showing a second embodiment and having a cylindrical shape and a thin cylindrical portion.

FIG. 3 shows an air cleaner hose of a third embodiment having a cylindrical shape and a groove-shaped portion with a thin wall thickness.
FIG. 3A is a sectional view thereof, and FIG. 3B is a perspective view when the hose is curved.

FIG. 4 is a perspective view of an air cleaner hose according to a fourth embodiment including a portion made of a material having rigidity lower than that of other portions.

FIG. 5 shows a prior art air cleaner hose,
FIG. 5 (a) is an external perspective view of an engine to which the air cleaner hose is attached, and FIG. 5 (b) is an explanatory view showing the state of the flow of air and blow-by gas in the air cleaner hose.

[Explanation of symbols]

1 ... Air intake duct 2 ... Air cleaner 3 ... Air cleaner hose 3a ... Upstream part of blow-by gas intake of air cleaner hose 3b ... Downstream part of blow-by gas intake of air cleaner hose 4 ... Surge tank 5 ... Intake manifold 6 ... Engine head cover 7 ... Blow-by gas recirculation passage 8 ... Blow-by gas intake 10 ... Engine 32 ... Intake shutter

Claims (2)

[Claims] 1. An air cleaner hose (3) for an engine having a shield-type blow-by gas reducing device in which a blow-by gas intake (8) is provided in an air cleaner hose (3) connected to a downstream side of the air cleaner (2). A shield type blow-by gas reduction, characterized in that a portion having lower rigidity than the upstream portion (3a) of the blow-by gas inlet (8) is provided in the downstream portion (3b) of the blow-by gas inlet (8). Air cleaner hose for engine with equipment. 2. The air cleaner hose for an engine according to claim 1, wherein the low rigidity portion is formed by an elastic member.