JP2000064919A - Intake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake device of an internal combustion engine, which can attempt compatibility between reduction of intake noise and improvement of output performance by a simple structure. SOLUTION: This intake device is equipped with a main duct 4, a sub-duct 5 connected to the main duct 4 so that an intake passage can be met and a reed valve 6 arranged in a confluent part 7, therefore the cross sectional area of the intake passage arranged further upstream from a throttle valve 9 can be varied. Therefore, when an intake flow speed is low, intake noise can be reduced by reducing the cross sectional area of the intake passage, and when the intake flow speed is high, intake efficiency can be improved by enlarging the cross sectional area of the intake passage. The reed valve 6 is operated by pressure difference between the main duct 4 and the sub-duct 5, therefore there is no more requirement to arrange a driving device and a control device for varying the cross sectional area of the intake passage, thus this intake device can be formed into a simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air intake device, and more particularly, to an air intake device connected to a device having a function of sucking air or an air-fuel mixture.

[0002]

2. Description of the Related Art An intake device such as an automobile engine supplies air or an air-fuel mixture to a combustion chamber mainly through an intake passage formed by an intake duct, an air cleaner, a throttle body and an intake manifold.

[0003] In order to improve the output performance of the engine by improving the intake efficiency in the high-speed rotation range, it is necessary to increase the sectional area of the intake passage. However, it is known that as the cross-sectional area of the intake passage increases, intake noise increases accordingly. Therefore, various devices have been devised to achieve the conflicting objectives of improving intake efficiency and reducing intake noise.

[0004] For example, in an air cleaner for a vehicle engine disclosed in Japanese Patent Application Laid-Open No. 61-76757, a slide valve is provided at a suction port of the air cleaner, and the slide valve is electrically controlled and driven to drive the suction valve. The opening area is variable. As a result, when the intake flow rate is low, the cross-sectional area of the intake passage is reduced to reduce intake noise in the low-speed rotation range of the engine, and when the intake flow rate is high, the intake area is increased by increasing the cross-sectional area. To improve the output performance of the engine in the high-speed rotation range.

[0005] In the variable air duct disclosed in Japanese Utility Model Laid-Open No. 4-123363, an intake duct is partitioned by a partition wall, and one intake duct is provided with a solenoid valve.
When the intake flow rate is low, air or air-fuel mixture is sucked in from only one of the partitioned intake ducts to reduce intake noise in the low-speed rotation range of the engine. Attempts are made to improve the intake performance by inhaling air or air-fuel mixture to improve the output performance of the engine in a high-speed rotation range.

[0006]

However, the mechanism for varying the cross-sectional area of the intake passage disclosed in JP-A-61-76757 and Japanese Utility Model Laid-Open No. 4-123363 has a variable cross-sectional area in each case. Therefore, there is a problem that an actuator or a control unit for driving a slide valve or an electromagnetic valve is required, and the number of parts is large and the cost is high.

The present invention has been devised in view of the above problems, and it is possible to reduce intake noise when the intake flow rate is low, and to improve intake efficiency when the intake flow rate is high.
It is an object of the present invention to provide an inexpensive intake device with a small number of parts.

[0008]

According to the intake device of the first aspect of the present invention, the first duct and the second duct connected thereto are connected.
By forming a plurality of intake passages by providing a duct,
In order to provide a valve for shutting off or communicating the intake passage in the first duct and the second duct at the junction of the first duct and the second duct and for preventing the inflow from the first duct to the second duct, the disconnection of the intake passage is performed. The area can be made variable. Therefore, when the intake flow velocity is low, the intake passage of the second duct is shut off to reduce the cross-sectional area of the intake passage to reduce intake noise, and when the intake flow velocity is high, the intake passage of the second duct is connected. Thus, the cross-sectional area of the intake passage can be increased, and the intake efficiency can be improved. Further, by forming a plurality of intake passages, the valves can be operated by the pressure difference in each intake passage, and a valve driving device for varying the cross-sectional area of the intake passage and electrical control are not required. Therefore, the number of parts is small and it can be manufactured at low cost.

According to the second aspect of the present invention, the second duct joins the first duct on the dust side of the air cleaner so as to form a plurality of intake passages on the dust side which is the inlet side of the air cleaner. In addition, the intake noise can be further reduced as compared with the case where a plurality of intake passages are formed on the clean side which is the outlet side of the air cleaner.

According to the third aspect of the present invention, the second duct joins the first duct on the clean side of the air cleaner so as to form a plurality of intake passages on the clean side of the air cleaner. The intake efficiency can be further improved as compared to forming a plurality of intake passages on the side.

According to the fourth aspect of the present invention, since the reed valve is provided at the junction of the first duct and the second duct, the reed valve operates according to the pressure difference between the respective ducts, The sectional area of the intake passage can be changed continuously.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIGS. 1, 2, and 6 show an air intake device according to a first embodiment of the present invention provided in an automobile engine.

As shown in FIG. 1, a main duct 4 as a first duct, an air cleaner 1, a throttle body 2, a surge tank 13, and an intake manifold 3 are connected to each other, and the internal space of each member is the same as that of an automobile engine (not shown). An intake passage for supplying air to the combustion chamber is formed. The sub duct 5 as the second duct is the main duct 4
, And the respective internal spaces are conductive.

The main duct 4 and the sub duct 5 are provided in parallel on the dust side of the air cleaner 1. One end of the main duct 4 has an intake port 11 for directly sucking outside air,
The other end is connected to the air cleaner 1 and the air cleaner 1
To form a dust side intake passage. One end of the sub duct 5 has an intake port 12 for directly sucking outside air, and the other end is connected to the main duct 4 at the junction 7 to form an auxiliary intake passage on the dust side of the air cleaner 1. The junction 7 is provided with a reed valve 6 described later.

The air cleaner 1 includes a cleaner case 101.
And a cleaner element 102, one end of which is connected to the main duct 4, and the other end of which is connected to the throttle body 2. The throttle body 2 is provided with a throttle valve 9 in an internal intake passage, and one end is connected to the air cleaner 1 and the other end is connected to a surge tank 13. The surge tank 13 has a shape that expands the intake passage, and one end is connected to the throttle body 2 and the other end is connected to the intake manifold 3.

One end of the intake manifold 3 is connected to the surge tank 13, and the intake passage is branched into a plurality of pipes so as to form branched pipes for supplying air to the respective combustion chambers of the automobile engine. Each end of the branched tube is connected to each combustion chamber of an automobile engine.

As shown in FIG. 6, the above-described reed valve 6 comprises a valve body 601 made of a thin metal plate and a stopper 602, and is screwed to the main duct 4, and
Is provided so as to close the confluence portion 7. When there is no pressure difference between the main duct 4 and the sub duct 5, the valve
As shown in FIG. 4, when the pressure difference between the main duct 4 and the sub duct 5 increases, the junction is lifted toward the main duct 4 according to the pressure difference, and the junction 7 is opened. Stopper 602
Determines the maximum opening angle of the valve body 601.

The operation of the intake device having the above configuration will be described. When the automobile engine starts, air according to the opening angle of the throttle valve 9 flows in from the intake port 11 or the intake port 12. The air flowed into the main duct 4
From the air cleaner 1 to the cleaner element 10
2 removes dust, passes through the throttle body 2 and the surge tank 13 and passes through the intake manifold 3.
And branches in the intake manifold 3 to flow into each combustion chamber of the vehicle engine.

When the vehicle engine is in the low speed rotation range, the pressure difference between the main duct 4 and the sub duct 5 is small, so that the reed valve 6 is completely closed as shown in FIG. When the reed valve 6 is completely closed, only the air sucked from the junction 11 of the main duct 4 flows into the air cleaner 1, so that the sectional area of the intake passage is small.

The internal pressure of a single intake pipe becomes negative due to the flow rate of intake air. As shown in FIG. 5, when the flow rate of intake air increases and the flow rate of intake air increases, the negative pressure in the intake pipe increases. For this reason, as shown in FIG. 2, the reed valve 6 is lifted in accordance with the pressure difference between the main duct 4 and the sub duct 5 to open the junction 7, and the air sucked from the intake port 12 of the sub duct 5 is supplied to the air cleaner 1. It comes in. Both the main duct 4 and the sub duct 5 form an intake passage, and the sectional area of the intake passage increases. Further, since the reed valve 6 includes the stopper 602, even if the pressure difference between the internal pressures of the main duct 4 and the sub duct 5 continues to increase, the reed valve 6 does not open more than a predetermined angle.

In general, the larger the cross-sectional area of the intake passage, the higher the intake efficiency in the high-speed rotation range and the higher the output performance of the automobile engine. On the other hand, since the intake noise increases as the cross-sectional area of the intake passage increases, the improvement of the intake efficiency and the reduction of the intake noise are in a contradictory relationship. Therefore, in the present embodiment, the main duct 4 and the sub duct 5 are provided in parallel, and the reed valve 6 that opens and closes the junction 7 by the pressure difference is provided, so that the cross-sectional area of the intake passage is continuously changed.
The output performance is improved by improving the intake efficiency in the high-speed rotation range, and the intake noise is reduced in the low-speed rotation range.

That is, in the low-speed rotation range, in order to reduce the intake noise, air is sucked only from the main duct 4 to reduce the cross-sectional area of the intake passage, and the intake efficiency is increased as the rotation speed of the automobile engine increases. In order to improve the intake air, the sectional area of the intake passage is increased by gradually sucking air from the sub duct 5. Therefore, the intake noise can be reduced in the low-speed rotation range of the automobile engine, and the intake efficiency can be improved in the high-speed rotation range to improve the output performance.

The reed valve 6 for making the cross-sectional area of the intake passage variable is operated by the pressure difference between the main duct 4 and the sub-duct 5. Therefore, an actuator or electric control for making the cross-sectional area of the intake passage variable is performed. It is not necessary, and can be manufactured at a low cost with a reduced number of parts compared to an intake device that requires an actuator or electrical control.

Further, when the cross-sectional area of the intake passage is reduced in the dust-side intake passage of the air cleaner 1, the intake noise is further reduced as compared with the case where the cross-sectional area of the intake passage is similarly reduced in the clean-side intake passage. Can be. Furthermore, it has versatility that can be installed in various types of internal combustion engines.

(Second Embodiment) FIG. 3 shows a second embodiment in which the intake device of the present invention having a main duct and a sub duct on the clean side of an air cleaner is applied to an automobile engine.
Shown in Parts substantially the same as those in the first embodiment are denoted by the same reference numerals.

As shown in FIG. 3, an inlet pipe 31 serving as a first duct, an air cleaner 1, a main duct 22, a throttle body 2, a surge tank 13, and an intake manifold 3 are connected to each other. An intake passage for supplying air to each intake port of the chamber is formed. The sub duct 23 as the second duct is connected to the main duct 22, and the respective internal spaces are electrically connected.
One end of the inlet pipe 31 has an intake port 32 for directly sucking outside air, and the other end is connected to the air cleaner 1.

The main duct 22 and the sub duct 23 are
It is provided in parallel with the clean side of the air cleaner 1.
One end of the main duct 22 is connected to the air cleaner 1,
The other end is connected to the throttle body 2 and forms a clean side intake passage of the air cleaner 1. One end of the sub duct 23 is connected to the air cleaner 1, and the other end is connected to the main duct 22 at a junction 29 to form an auxiliary intake passage on the clean side of the air cleaner 1.
The junction 29 is provided with the reed valve 6.

When the automobile engine starts, air corresponding to the opening angle of the throttle valve 9 flows in from the intake port 32. The inflowing air flows into the air cleaner 1 from the inlet pipe 31, and dust is removed by the cleaner element 102, flows into the main duct 22 or the sub duct 23, passes through the throttle body 2 and the surge tank 13, and flows into the intake manifold 3. Then, it branches in the intake manifold 3 and flows into each combustion chamber of the automobile engine.

The operation of the air intake system of the second embodiment is different from that of the air intake system of the first embodiment in that a main duct 22 and a sub duct 23 are provided on the clean side of the air cleaner 1, and the reed valve 6 controls the air cleaner 1. The point is that the cross-sectional area of the clean side intake passage is made variable.

Therefore, the effect provided by the intake device of the second embodiment is different from the effect provided by the intake device of the first embodiment, in that the cross-sectional area of the intake passage in the clean side intake passage of the air cleaner 1 is increased. By doing so, the intake efficiency in the high-speed rotation range of the vehicle engine is further improved as compared with increasing the cross-sectional area of the intake passage in the dust-side intake passage.

That is, when the cross-sectional area is made variable on the dust side of the air cleaner as in the first embodiment, there is an advantage that reduction of intake noise can be prioritized, and as in the second embodiment, disconnection is made on the clean side of the air cleaner. When the area is made variable, there is an advantage that the intake efficiency when the intake flow velocity is high can be prioritized.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an intake device according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of the intake device according to the first embodiment of the present invention.

FIG. 3 is a schematic sectional view of an intake device according to a second embodiment of the present invention.

FIG. 4 is a graph showing a relationship between a pressure difference between a main duct and a sub duct and a lift amount of a valve body in the first embodiment of the present invention.

FIG. 5 is a graph showing a relationship between an intake flow rate and a pressure in a single intake pipe.

FIG. 6 is a perspective view of a reed valve according to the first embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air cleaner (1st duct) 2 Throttle body (1st duct) 3 Intake manifold (1st duct) 4, 22 Main duct (1st duct) 5, 23 Subduct (2nd duct) 6 Reed valve (valve) 7, 29 Junction 9 Throttle valve 13 Surge tank (first duct)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G031 AA02 AA15 AA28 AB02 AC01 BA07 BA14 BB04 DA31 DA37 EA03 FA11 GA08 GA13 HA04 HA08 HA09 HA10 3H058 AA15 BB22 EE04 EE15

Claims (4)

[Claims] 1. An intake device for forming an intake passage through which air or an air-fuel mixture flows, comprising: a first duct having a throttle valve; and the first duct such that the intake passage merges on the inlet side of the throttle valve. A second duct, which is provided at a junction of the first duct and the second duct, and blocks or communicates an intake passage in the first duct and an intake passage in the second duct; A valve for suppressing the inflow of air or air-fuel mixture from the first duct to the second duct. 2. The intake device according to claim 1, wherein the first duct has an air cleaner, and the second duct is connected to the first duct on an inlet side of the air cleaner. 3. The air conditioner according to claim 1, wherein the first duct has an air cleaner, and the second duct is connected to the first duct at an outlet side of the air cleaner. Intake device. 4. The intake device according to claim 1, wherein the valve is a reed valve.