JPH11107738A - Intake device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the ability to remove the oil and water contained in blow-by gas without complicating structure. SOLUTION: A trapper room 42 for collecting the oil and water contained in the blow-by gas recovered from the crank case of an engine is provided in the boundary section between an air cleaner section 10 and a surge tank 40. This trapper room 42 comprises two collection rooms 100a and 110 having a passage of labyrinth structure. Molded body filters are contained in the inside space of the collection rooms 100 and 110 without clearance along the labyrinth structure. When the blow-by gas taken in each of collection rooms 100 and 110 pass through the molded filters, oil and water are collected from the gas. The gas is absorbed in an intake device after oil and water are removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake device for an internal combustion engine in which an air cleaner, an intake manifold and the like are integrated.

[0002]

2. Description of the Related Art An ordinary vehicle includes an internal combustion engine (engine).
A blow-by gas reduction device that releases the combustible gas containing hydrocarbons released from the crankcase to the intake side of the engine again without releasing it to the atmosphere and recombustes it, while forcibly ventilating the inside of the crankcase ( PCV; Positive Cra
nkcase Ventilation). HC released into the atmosphere by reburning blow-by gas
Can be reduced.

[0003] The above-mentioned blow-by gas contains a large amount of oil and moisture, and when these are introduced into the intake device, many inconveniences are caused. For example, when the aero flow meter that measures the amount of air flowing into the intake device or the pressure sensor that measures the pressure in the throttle or the surge tank is contaminated with the above-described oil or moisture, measurement using the respective components is performed. An error occurs in the result, and a deviation from an appropriate value also occurs in engine control based on these measurement results. Further, if the above-mentioned moisture is sucked in the vicinity of the throttle, the throttle valve may be locked immediately after the engine is started at a low temperature due to freezing of the moisture attached thereto.

[0004] As a method of preventing such various inconveniences, the simplest case is to remove oil and moisture contained in the blow-by gas through the maze structure when returning the blow-by gas to the intake device. . Further, in order to prevent icing when moisture in the blow-by gas adheres to the throttle valve, a method of heating the throttle body with engine cooling water as disclosed in Japanese Utility Model Laid-Open No. 57-126560 has been known. ing.

[0005]

By simply providing the maze structure as described above, it can be expected to remove oil and moisture in the blow-by gas.
When the amount of oil or moisture in the blow-by gas increases, or when exhaust regulations are strict as in recent years, there is a possibility that the performance of removing oil and the like may not be sufficient simply by forming a maze structure. Further, as disclosed in Japanese Utility Model Laid-Open No. 57-126560, when the throttle body is heated by the engine cooling water, when the throttle body is made of a resin material due to a demand for weight reduction and cost reduction, Since the heat conductivity is low, ice attached to the throttle valve is hard to melt, and lock due to icing of the throttle valve may not be sufficiently prevented in spite of the complicated structure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object the structure thereof is not complicated, and the ability to remove oil and moisture contained in blow-by gas can be improved. An intake device for an internal combustion engine is provided.

[0007]

In order to solve the above-mentioned problems, an intake device for an internal combustion engine according to the present invention forms a part of a blow-by gas return passage in a maze structure and accommodates the maze structure along the maze structure. The blow-by gas is passed through the formed compact filter. Therefore, when blow-by gas guided from the crankcase of the internal combustion engine passes through this maze structure,
The molded body filter can efficiently remove oil, moisture, and the like in the blow-by gas.

In particular, the above-mentioned molded body filter is preferably formed by using a fiber material having air permeability, and by increasing the surface area by using such a molded body filter, the blow-by gas in the passing blow-by gas can be formed. It is possible to efficiently collect oil and water, and to provide them with sufficient removal ability. Further, it is preferable that the above-mentioned formed body filter is integrally formed in accordance with the shape of the maze structure. The molded body filter having such a shape can be mounted by fitting the filter into a maze structure, so that the number of parts is reduced and the assembling work is facilitated.

Further, it is preferable that the maze structure for accommodating the molded body filter is disposed so as to be adjacent to the air cleaner and the surge tank. In general, when performing blow-by gas reduction, in order to efficiently reduce blow-by gas, air is flowed into the crankcase of the internal combustion engine from the air cleaner portion that is on the upstream side of the throttle, and air containing blow-by gas discharged from the crankcase is discharged. Inhaled into the surge tank downstream of the throttle. As described above, since it is necessary to extend two types of pipes connected to the crankcase of the internal combustion engine from each of the air cleaner section and the surge tank, the maze structure is arranged adjacent to the air cleaner section and the surge tank. The maze structure corresponding to the different types of pipes and the molded body filter accommodated in the maze structure can be integrated at one place, so that the structure of the intake device can be simplified and the work of assembling the molded body filter becomes easy.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An engine intake device according to an embodiment of the present invention includes an oil intake blow-by gas flowing from a crankcase of an engine at a position adjacent to an air cleaner portion of a surge tank. It is characterized in that a trapper chamber having a maze structure for collecting and separating water and moisture is provided, and a formed body filter is stored in the maze structure. Hereinafter, an intake device for an engine according to an embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a view showing the structure of an intake device for an engine according to an embodiment to which the present invention is applied. FIG. 2 is an enlarged sectional view taken along the line II-II shown in FIG. As shown in FIGS. 1 and 2, the air intake device of the present embodiment includes an air cleaner unit 10 that removes dust contained in air taken in from an intake port 12 and attaches the air intake device to an engine (not shown). An intake manifold 20 having an attachment portion 22 formed at one end, and each branch pipe 2 of the intake manifold 20
4, a delivery pipe 32 that supplies fuel to the injector 30, a surge tank 40 provided at the other end of the intake manifold 20, and an end of the surge tank 40. The throttle 50 includes a throttle 50 attached to the portion, and a passage 60 connecting the throttle 50 and the air cleaner portion 10.

The components of the above-described intake device are integrated. For example, as shown in FIG. 2, a part of the air cleaner section 10 and the intake manifold 2 are formed by the housing 70.
0 and a surge tank 40 are formed, and a cap 72 or the like including a part of the air cleaner unit 10 is attached thereto, and the whole is integrated. Hereinafter, the configuration of each part of the above-described intake device will be described in detail. The air cleaner unit 10 includes an air cleaner element 14 made of nonwoven fabric or filter paper, a guide 16 for mounting and storing the air cleaner element 14,
The air cleaner case 18 includes a part of the housing 70 and the cap 72.
In the air cleaner case 18, the dusty side case 80 is located upstream of the intake air and the clean side case 82 is located downstream of the air cleaner element 14.
The space surrounded by the respective cases 80 and 82 is called a dusty side space and a clean side space.

The dusty side space in the dusty side case 80 and the clean side space in the clean side case 82 are separated by the air cleaner element 14 mounted on the guide 16 therebetween. The air introduced into the space passes through the air cleaner element 14 to remove dust and is introduced into the clean side space. This guide 16
Can be attached and detached by sliding in the vertical direction with respect to the flow of air through the air cleaner element 14, and when attached to the air cleaner unit 10, a seal member (not shown) formed on the outer periphery thereof allows The dusty side space and the clean side space are separated. Also, the guide 16 has a function as a cover that covers the mounting opening formed in the air cleaner case 18 without any gap, and prevents the air from flowing into the dusty side space through this opening. ing.

The passage 60 is provided in the air cleaner element 14.
For guiding the air passed through the clean side space to the surge tank 40 through the throttle 50, and is formed in a U-shape having a circular cross section. The throttle 50 includes a throttle valve and a throttle body, and adjusts an amount of air taken into each cylinder row of the engine. The throttle 50 has a pressure sensor 52 for detecting the pressure in the throttle 50.
And a position sensor 54 for detecting the opening of the throttle valve are attached, and the outputs of these sensors are input to an engine control unit (ECU) (not shown).

The surge tank 40 distributes the air taken in through a throttle 50 attached to an end to each branch pipe 24 of the intake manifold 20. Further, a trapper chamber 42 is formed for separating a part of the surge tank 40 to collect oil and water, and separates oil and water contained in blow-by gas collected from a crankcase of the engine. The detailed structure of the trapper chamber 42 will be described later.

The intake manifold 20 includes a surge tank 4
This is for introducing the air from which the dust introduced through the cylinder 0 has been removed into each cylinder row of the engine, and is constituted by the same number of branch pipes 24 as the number of cylinders of the engine. For example, the engine to which the intake device of the present embodiment is attached is a three-cylinder engine, and the intake manifold 20 includes three branch pipes 24. At the tip of each branch pipe 24 (the end opposite to the surge tank 40), a mounting portion 22 for mounting the intake device to the engine is formed, and a bolt insertion hole 26 provided in the mounting portion 22 is formed. The installation of the intake device to the engine is performed by tightening through a bolt (not shown).

The injector 30 injects fuel (gasoline) supplied from a tubular delivery pipe 32 as a fuel supply device into the engine at a predetermined timing. In the vicinity of the distal end of each branch pipe 24 of the intake manifold 20, there is formed a mounting hole 28 which penetrates a straight pipe by connecting the mounting surface of the mounting portion 22 and the dusty side space of the air cleaner portion 10. The injector 30 is inserted. The injector 30 is fixed by fixing the delivery pipe 32 attached to the end (the dusty side case 80 side of the air cleaner unit 10).

FIG. 3 is a plan view of the intake device of the present embodiment, and shows a partial cross section of the trapper chamber 42. FIG. 4 is a sectional view taken along line IV-IV of FIG. FIG. 5 is a sectional view taken along line VV of FIG. FIG. 6 shows V in FIG.
It is an I-VI line sectional view. As shown in these figures, the trapper chamber 42 includes two collection chambers 100 and 110 having a maze-structured passage. Any collection room 10
0 and 110 are also formed adjacent to the surge tank 40 and the air cleaner unit 10.

One collection chamber 100 is provided with a discharge port 102 provided at one end of a maze-structured passage and a ventilation hole provided at the other end of the maze-structured passage at a boundary wall 104 with the air cleaner portion 10. The mouth 106 and a molded body filter 108 (to be described later) integrally molded in accordance with the shape of the maze structure.
And The discharge port 102 is for fitting a pipe as a reduction passage connecting the crank chamber of the engine, and the ventilation port 106 is for taking in air from a clean side space of the air cleaner unit 10.
Each of the cross-sectional views shown in FIGS. 3 to 6 shows a structure excluding the molded body filter 108 or a molded body filter 118 described later.

FIG. 7 is a perspective view showing the external shape of the molded body filter 108. The molded body filter 108 has a predetermined number of turn-back structures that is the same as the shape of the internal space of the collection chamber 100 so that it can be housed in the collection chamber 100 having a maze structure without a gap. As shown in FIG. 7, the molded body filter 108 has two concave portions which are alternately formed from opposite directions, and each of these concave portions and each convex portion which constitutes a maze structure of the collection chamber 100. Assembling of the compact filter 108 is performed so as to engage with each other.

The other collecting chamber 110 has a suction port 112 provided at one end of a maze-structured passage and a boundary wall 11 between the other end of the maze-structured passage and the surge tank 40.
4 and a molded body filter 118 integrally formed in accordance with the shape of the maze structure. The suction port 112 is for fitting a pipe as a reduction passage connecting the crank chamber of the engine, and the ventilation port 116 is for taking in blow-by gas into the surge tank 40. Further, similarly to the above-described molded body filter 108, the molded body filter 118 is the same as FIG.
Collection chamber 11 having a shape shown in FIG.
The trapping chamber 110 has the same number of turns as the inside space of the collection chamber 110 so that it can be housed without any gaps inside.

Each of the above-mentioned molded body filters 108 and 118 is formed of a breathable fiber material and has a large surface area. For example, fibers such as pulp and polyester are dispersed in water, and this liquid is filtered with a molding die, formed into a shape as shown in FIG. 7, and then dried and solidified, whereby the formed body filters 108 and 118 are formed. You. The formed body filters 108 and 118 thus formed are like hard cotton and have good air permeability. Also, the molded body filters 108 and 118
In order to prevent the fibers constituting the fibers from falling apart, a binder is mixed in water to disperse the fibers during molding, and the fibers are bonded to each other by the binder during drying, or bonded after drying. It is desirable to take a technique of impregnating the material and further solidifying the binder by heating.

In a normal operation in which the engine is rotating, the clean side space of the air cleaner unit 10 upstream of the throttle 50 is at atmospheric pressure, and the pressure in the surge tank 40 downstream of the throttle 50 is negative. ing. Therefore, the blow-by gas filled in the crankcase of the engine is exhausted by the negative pressure in the surge tank 40, and fresh air is sent from the clean side space of the air cleaner unit 10 into the crankcase instead. In this way, the blow-by gas in the crankcase is reduced and collected in the surge tank 40 of the intake device, and the inside of the crankcase is forcibly ventilated.

The blow-by gas collected in the surge tank 40 from the crankcase of the engine in this manner contains oil and moisture.
Molded article filter 1 stored therein when passing through
Collected by 18. In particular, the forming filter 118
Is housed in the entire maze structure in the collection chamber 110 without any gap, has a long path length in the blow-by gas reduction passage, and has a large surface area because it is formed using a fiber material. The trapping ability, that is, the performance of removing oil and moisture is high, and the oil and moisture can be sufficiently removed from the blow-by gas. As described above, since the oil content and moisture in the blow-by gas introduced into the surge tank 40 through the ventilation port 116 of the collection chamber 110 are removed, the pressure sensor 52 communicating with the inner wall side of the throttle 50 is removed. It is possible to prevent deposits (dirt) on the pressure detection surface caused by oil or moisture adhering to the pressure detection surface.
The deviation of the engine control amount from the appropriate state accompanying this can be eliminated. Further, since dry blow-by gas can be introduced into the surge tank 40, moisture adhering to the throttle valve in the throttle 50 can be reduced,
It is possible to prevent the throttle valve from locking due to icing at a low temperature start.

Further, since the air sent from the air cleaner section 10 to the crankcase of the engine passes through the other collection chamber 100, it seems that it is not necessary to remove oil and moisture in the blow-by gas. However, actually, when the pressure in the crankcase becomes higher than the atmospheric pressure, the blow-by gas in the crankcase flows back to the air cleaner unit 10. By collecting the oil and moisture contained in the blow-by gas through the molded body filter 108 in the collection chamber 100, the oil and moisture are removed from the clean side space of the air cleaner unit 10 to the slot 50 side through the passage 60. Since the blow-by gas that has been removed can flow, it is possible to reduce the amount of oil and moisture attached to the pressure sensor 52 and the throttle valve.

The two collecting chambers 100, 11
By forming the trapper chamber 42 made of zero so as to be adjacent to the air cleaner unit 10 and the surge tank 40, only the ventilation holes 106, 116 are provided in the boundary walls 104, 114 to allow the air to pass between the air cleaner unit 10 and the surge tank 40. The blow-by gas return passage can be secured,
Necessary piping can be simplified.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, in the above-described embodiment, the oil component and the moisture contained in the blow-by gas are removed to reduce the oil component and the moisture attached to the pressure sensor 52 and the throttle valve. This also has the effect of reducing the amount of oil and the like adhering to the parts. For example, when an air flow meter for measuring a flow rate is provided in a part of the intake passage, or when an ISCV (idle speed control valve) that bypasses a passage through a throttle valve is provided, oil adhering to these is provided. Minutes and moisture can also be reduced.

In the above-described embodiment, the molded body filter 108 or 118 is stored in both of the two collection chambers 100 and 110, but may be stored in only one of them. Alternatively, the collection chamber 100, 1
Only one of them may be provided. Further, the molded body filter 108 used in the above-described embodiment,
Reference numeral 118 denotes a folded shape that completely fills the internal space of the collection chambers 100 and 110 having a maze structure, but as shown in FIG. 8, a state in which the wall members 120 are alternately inserted from two directions. The molded body filter 122 may be molded by using. By forming the entire body including the wall member 120 as the molded body filter 122 in this manner,
The collection chambers 100 and 1 for accommodating the molded body filter 122
The shape of the trapper chamber 4 including the collection chambers 100 and 110 can be a simple box shape with the convex portions removed.
2 (or housing 7 containing this trapper chamber 42)
The mold required for forming 0) can be formed into a simple shape, which facilitates production, increases the life of the mold, and reduces production cost.

Further, in the above-described embodiment, the formed body filters 108 and 11 having a folded shape integrally formed are provided.
8 is embedded in each internal space of the collection chambers 100 and 110 having a maze structure without any gap. However, the molded body filter 108 and the like are disassembled by a plurality of filter pieces, and each filter piece is separated from the collection chamber 100 and the like. It may be arranged so as to be embedded in the internal space without any gap. In this case, the filter pieces do not necessarily have to be arranged in close contact with each other, but may be arranged at positions separated by a predetermined distance.

In the above-described embodiment, the trapper chamber 42 is formed at the boundary between the air cleaner section 10 and the surge tank 40. However, the trapper chamber 42 may be formed separately from the intake device, or the two trap chambers may be formed. 100 and 110 may be divided so that one collection chamber 100 is formed at a position adjacent to the air cleaner unit 10 and the other collection chamber 110 is formed at a position adjacent to the surge tank 40.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure of an intake device for an engine according to an embodiment to which the present invention is applied.

FIG. 2 is an enlarged sectional view taken along line II-II shown in FIG.

FIG. 3 is a plan view of the intake device of the embodiment.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a sectional view taken along line VV of FIG. 4;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 4;

FIG. 7 is a perspective view showing an external shape of a molded body filter.

FIG. 8 is a perspective view showing an external shape of a modified example of the formed body filter.

[Explanation of symbols]

 Reference Signs List 10 air cleaner section 18 air cleaner case 40 surge tank 42 trapper chamber 50 throttle 60 passage 100, 110 collection chamber 102 discharge port 104, 114 boundary wall 106, 116 ventilation port 108, 118 molded body filter 112 suction port

Claims (4)

[Claims] 1. An intake device for an internal combustion engine, wherein a part of a return passage for blow-by gas is formed in a maze structure, and a formed body filter is stored along the maze structure. 2. The molded article filter according to claim 1, wherein the molded article filter is formed by using a fiber material having air permeability, and the blow-by gas is passed through the molded article filter housed in the maze structure. Intake device for an internal combustion engine. 3. The intake device for an internal combustion engine according to claim 1, wherein the formed body filter is integrally formed according to a shape of the maze structure. 4. The intake device for an internal combustion engine according to claim 1, wherein the maze structure is disposed adjacent to an air cleaner and a surge tank.