Air cleaner for an internal combustion engine

Field of the invention

The present invention relates to "An air cleaner for an internal combustion engine", and more particularly to an air cleaner provided above a power unit and below the storage box and pillion seat of a scooter type motorcycle.

Background of the invention

An air induction system supplies air to the combustion chamber of the engine. One component of the air induction system is commonly an air cleaner. The air cleaner is provided in the air intake structure of the engine to clean out the impurities in the air before the cleaned air is guided into the engine for combustion. The air cleaner receives incoming fresh air, which passes through a filter in order to remove impurities and directs the filtered air to the engine where the air is mixed with fuel. It is desirable to provide filtered and cleaned air to the engine so as to achieve a more efficient combustion process and to extend the operational life of the vehicle's engine.

Further the air cleaner is typically separated into two chambers; a first chamber receives ambient, unfiltered air containing certain impurities e.g., dirt, dust, etc. The ambient air is directed through an air filter to a second chamber. The second chamber receives the clean, filtered air and directs the air to the engine. Partition wall containing foam like material which acts as air filter, for filtering the dust like particles, is normally placed between the two chambers for separating the said two chambers.

Normally a scooter-type motorcycle includes a body frame, a power unit swingably supported on the body frame, a storage box arranged above the power unit and below the occupant seat. The air cleaner is normally arranged between the power unit and the storage box. A duct is mounted to the intake port of the air cleaner and extended to a suitable length to introduce the outside air to the intake port of the air cleaner. Presently, the intake port of air cleaner for sucking atmospheric air into the intake chamber of the air cleaner is greatly affected by external agents such as water and dust from front from near and rear wheel. An increased amount of entry of the dirt and water particles in to the air filter affects the desirable performance of the air filter air cleaner and thereby affecting the performance of engine and life of engine components.

Hence there exists a need for an air cleaner that overcomes the above said lacunas in the prior art.

Another objective of the present invention is to provide a means for efficient air filtering system, which is compact in size, and have better cleaning properties than the air cleaner present in the prior art.

Brief description of the invention

For solving the above said problems associated with the prior art, an air cleaner is provided which comprises an air filter housing, air filter cover, and an air inlet connected with an air inlet on the outer wall of the said air filter housing through which atmospheric air is introduced and an air outlet connected with an intake hose at a second side of said air cleaner for supplying the air to a combustion chamber. The air cleaner also constitutes a separating partition wall separating the said air cleaner into two partitions namely primary and secondary filtration area such that the partition wall is closer to the air inlet position. Moreover, the secondary filtration area is divided into pre-filtration and post filtration area. In this construction of the air cleaner, a sleeve with at least two venturi pipe like projections having progressively increasing diameter, made perpendicular to the face of the partition wall is provided. In this air cleaner, the said partition wall facilitates air filtration wherein the air from outside hits the said partition wall and expands in the primary filtration area and as a result the pressure is reduced which passes through the multi channel venturi projections and is spread uniformly in the secondary filtration area.

Brief description of drawings

Figure 1 shows a representative view of a scooter type motorcycle according to the present invention

Figure 2 shows the top perspective view of air cleaner

Figure 3 shows various views of the air cleaner wherein (i) shows the top view of air cleaner, (ii) shows the right side view of the air cleaner, (iii) shows the front view of the air cleaner from left side and (iv) shows left side view of the air cleaner

Figure 4 shows the cut section of an air cleaner showing the present invention according to section AA as in Figure 3(iii).

Figure 5 shows various views of cover air filter wherein (i) shows the inner view of the cover air filter and (ii) shows the perspective inner view of the cover air filter.

Figure 6 shows the sectional view of the air cleaner BB as in Figure 3(i)

Figure 7 shows the housing air filter wherein (i),(ii),(iii) and (iv) are Left, Inside, Right and bottom view respectively.

Figure 8 shows the sleeve arrangement wherein (i), (ii), (iii) and (iv) are Left, Front, Right and Top side view respectively.

Detailed description of the invention

Figures 1 to 8 show a working example of the present invention. A scooter-type motorcycle (Figure 1) includes a frame assembly, which usually supports the body of a scooter, along with front and rear wheels. A frame assembly (101) for a scooter-type vehicle comprises of at least one front wheel, at least one rear wheel and a vehicle body.

Typically, a frame assembly (101) for a scooter type motorcycle comprises a main frame and it may also have a sub-frame. The sub-frame is attached to the mainframe using appropriate fastening members. All the other components such as the body panels (109), the engine (102), and the electrical units are mounted on the main frame and the sub frame either directly or by means of brackets and fastening members.

The frame assembly (101) includes a head tube, which supports a front wheel suspension assembly (103) of the vehicle. An upper frame extends from the head tube to a rearward end of the vehicle body. A swing arm (104) is pivotally supported by the upper frame and supports a rear wheel of the vehicle. The frame assembly (101) may include a lower frame removeably coupled to the upper frame and defining a space (107) there between.

The sub-frame preferably supports at least one component of the scooter-type vehicle in the space, such as a fuel tank, for example.

Typically, front (103) and rear (104) suspension assemblies are operatively positioned between the front and rear wheels and the frame assembly. The front suspension assembly (103) commonly is a telescopic fork arrangement, while the rear suspension assembly (104) is a swing type arrangement. In a scooter, the rear suspension (104) swing arm typically supports a power unit (102), which is configured to drive the rear wheel of the scooter.

The power unit (102), is coupled along with a transmission assembly (108), such as a drive shaft, drive belt, or chain and sprocket assembly.

The frame assembly (101) of a scooter-type vehicle is an elongated structure, which typically extends from a forward end to a rearward end of the scooter. A scooter frame assembly generally is convex in shape, as viewed from a side elevational view. A handlebar assembly (105) and a seat assembly (106) are supported at opposing ends of the frame assembly (101) and a generally open area is defined there between (107).

Accordingly, the open area (107) between the handlebar assembly (105) and the seat assembly (106) allows the scooter to be easily straddled, or mounted, as opposed to a typical motorcycle, wherein a motorcycle fuel tank occupies the space between the handlebar assembly (105) and the seat assembly (107). Such an arrangement may be referred to as a "step-through" frame assembly. The air cleaner (1) is positioned below the body panels (109) and located underneath the seat (106).

The present invention (Figure 2, Figure 3 and Figure 4) in the said air cleaner (1) relates to the air filtration structure and the components associated in it. The air cleaner (1) is made of resin, and is divided into two main parts: an air filter housing (2) and an air filter cover (3). The housing (2) of air cleaner is further divided into two partitions with a wall (4) separating them. The separating partition wall (4) is located away from the mid of air filter along the larger width portion of the housing (2), such that the partition wall (4) is closer to the air inlet portion. A U shaped wall (5) is integrally formed on the partition wall (4) of the housing on the top surface of the housing.

An air inlet hole (9) is provided in the outer wall of the air filter housing (2) nearly parallel to the partition wall (4). The top portion of the partition wall (4) and the top portion of the housing (2) have parallel surfaces. The top face of the air filter housing (2) is attached with a flange (10) portion extending below the top level of the housing (2), such that the width of the flange (10) is nearly three times the basic wall thickness of the air filter housing (2). A groove (11) is formed in the U shape of the face flange (10) extending away from the top surface of the housing to form a uniform wall thickness along the periphery. The air filter housing (2) is also provided with ribs (12) on the inner side of the housing (2) extending little away from the side wall perpendicular to the housing, such that the ribs (12) are provided on the partition wall (4). The U shaped wall (5) projects out of the inner wall surface of the cover (3), such that the wall formed is nearly one third of the height of the cover when viewed from the cover side. A sleeve (16) made of elostomer is provided between the U shaped projections (14) in the cover (3) and the partition wall (4) in the air filter housing (2) (Figure 5, Figure 6, Figure 7 and Figure 8). The sleeve (16) is nearly rectangular in shape and includes a set of circular shaped projections (17) perpendicular to the face of the housing. The circular projections (17) are formed in such a way to form a venturi (18) such that the larger diameter of the projection (17) is located on the opposite side of the air entry in the air filter housing (2).

A support plate (19) made of resin is provided in the air filter housing (2), such that the outer periphery of the support plate (19) matches the inner profile of the air filter housing (2). The support plate (19) is provided with large openings to allow the air to pass through it. A foam like filtering member (20) is placed over the support plate (19) such that the outer periphery of the filtering member (20) matches the shape of support plate (19) which extends little away to tightly fit the filtering member (20) on the inner side of the air filter housing (2).

A cover plate (22) is provided on the partition wall (4) in the air filter housing (2) and a tapping hole (23) is formed in the extreme end of the cover plate (22) for tapping the air in the primary filtration area to the engine unit for secondary air injection requirements.

The air from the atmosphere enters to the air cleaner (1) through the air inlet hole (9) provided in the outer wall of the air filter housing (2) nearly parallel to the partition wall (4). The primary filtration of the atmospheric air from the dust and particulates are performed in the inlet chamber. The primarily filtered air then enters through the venturi (18) formed in the pipe like projections (17) made on the sleeve (16). The sleeves with pipe like projections (17) are made perpendicular to the face of the partition wall (4). The venturi (18) in the pipe like projections (17) creates a pressure difference between the primary filtration area and the secondary filtration area that enables a uniform flow of air from the primary filtration to the secondary filtration area. The foam like filtering member (20) is provided in the secondary filtration area that passes the clean and dust free air to the outlet (21) of the filter housing.

Part numbers associated with the drawings

1. Air filter
2. Air filter housing
3. Air filter cover
4. Partition wall
5. U shaped wall
9. Air inlet hole
10. Flange
11. Groove
12. Ribs
13. Flange
16. Sleeve
17. Circular projections
18. Venturi
19. Support plate
20. Foam like filtering member
21. Air filter outlet
22. Cover plate
23. Tapping hole

We claim:

1. An air cleaner for a vehicle comprising:

an air filter housing 2, air filter cover 3, and an air inlet connected with an air inlet 9 on the outer wall of the said air filter housing 2 through which atmospheric air is introduced and an air outlet 21 connected with an intake those at a second side of said air filter for supplying the air to a combustion chamber;

a separating partition wall 4 separating the said air cleaner into two partitions namely primary and secondary filtration area such that the partition wall 4 is closer to the air inlet position 9;

the secondary filtration area is divided into pre-filtration and post filtration area;

a U shaped wall 5 integrally formed on the said partition wall 4;

wherein the said cleaner includes a sleeve 16 with at least two venturi pipe like projections 18 having progressively increasing diameter, made perpendicular to the face of the partition wall 4.

2. The air cleaner as claimed in claim 1, the said partition wall 4 facilitates air filtration wherein the air from outside hits the said partition wall 4 and expands in the primary filtration area and as a result the pressure is reduced which passes through the multi channel venturi projections 18 and is spread uniformly in the secondary filtration area.

3. The air cleaner as claimed in claim 1, wherein the said circular projections form a venturi 18 such that the larger diameter of the projection is located opposite side of the air entry in the said air filter housing.

4. The air cleaner as claimed substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.