Air induction systems for internal combustion engines

Air induction systems are for an internal combustion engine. The air induction systems comprise an air intake plenum that conducts intake airflow to an air cleaner for cleaning prior to combustion in the internal combustion engine. The air intake plenum is movable with respect to the air cleaner between an open position separated from the air cleaner and a closed position connected to the air cleaner. A bellows connects the air intake plenum to the air cleaner when the air intake plenum is in the closed position. The bellows has an upstream first end that seals with the air intake plenum and a downstream second end that seals with the air cleaner.

FIELD

The present application relates to air induction systems for internal combustion systems.

BACKGROUND

U.S. Pat. No. 4,378,945 discloses a bellows-type spring seal having a flexible bellows with an upper sealing end adapted to mate with a bell housing of an air intake pipe. The seal provides an effective breakaway joint when the cab is tilted forward from over the engine. A means, such as coil springs, encircles the bellows to push upon the underside of the sealing end of the bellows to provide a positive preload sealing force. The seal is self-aligning in the vertical and horizontal planes to accommodate cab rocking and minor misalignment in manufacture of the truck.

U.S. Pat. No. 4,974,881 discloses an air flow conduit system for air flow communication between an air filter mechanism and an engine intake manifold. The conduit system comprises first, second and third substantially rigid conduit members. Engagement between conduit members is provided by a rib system on a narrow end of a conduit member being received within a broad end of a next adjacent conduit member. Sealing engagement occurs by an elastomeric seal member positioned between the ribs and an end of a conduit member within which the ribs are received. A preferred rib arrangement is provided, to insure a flexible, multi-point, seal system.

U.S. Pat. No. 5,129,685 discloses an air flow conduit system for air flow communication between an air filter mechanism and an engine intake manifold. The conduit system comprises substantially rigid straight conduit members joined in fluid communication by connector systems having elbow-shaped conduit members. A narrow end of a conduit member is received within a broad end of a next adjacent conduit member. Sealing engagement occurs via an elastomeric seal member having ribs thereon positioned radially between the inner and outer conduits. A preferred rib arrangement is provided, to insure a flexible, multi-point, seal system.

SUMMARY

Air induction systems are provided for an internal combustion engine. In certain examples, the air induction system comprises an air intake plenum that conducts intake airflow to an air cleaner for cleaning prior to combustion in the internal combustion engine. The air intake plenum is movable with respect to the air cleaner between an open position separated from the air cleaner and a closed position connected to the air cleaner. A bellows connects the air intake plenum to the air cleaner when the air intake plenum is in the closed position. The bellows has an upstream first end that seals with the air intake plenum and a downstream second end that seals with the air cleaner. A spring is disposed in the bellows. The spring applies a biasing pressure on the bellows that encourages sealing between the bellows and at least one of the air intake plenum and the air cleaner when the air intake plenum is in the closed position. A shield blocks inflow of rain water to the bellows when the air intake plenum is in the open position.

DETAILED DESCRIPTION OF THE DRAWINGS

Through research and development, the present inventors have endeavored to provide long-term flexible and durable sealing joints between air intake plenums and an air cleaners providing combustion air to internal combustion engines. In such applications, the present inventors have found it desirable to control intake air temperature rises to within 5° F. The present inventors have also found it desirable to prevent environmental elements such as rain, snow, dust, etc. from entering the sealing joint and interfering with operation of the air cleaner.

FIGS. 1-3depict an air induction system20for a vehicle22. In this example, the air induction system20is adapted for use with a truck; however the air induction system20of the present disclosure can be adapted for use with a variety of different vehicles, including other types of on- and off-road trucks, cars, and/or the like. The air induction system20includes an air intake plenum24and an air cleaner26for cleaning the intake air prior to combustion in an internal combustion engine, shown schematically at28. The air cleaner26is a conventional intake air filter having a housing and filter media for filtering particular matter and/or other contaminants from the intake air; however this example is not limiting. The air induction system20of the present disclosure can be adapted for use with any conventional device for cleaning intake air.

As shown by arrows A, the air intake plenum24conducts intake airflow from the atmosphere surrounding the vehicle22to the air cleaner26, which resides under the hood30of the vehicle22. The air intake plenum24is formed under the hood30of the vehicle22and receives intake airflow via opposing inlets32on the hood30. In this example, the air intake plenum24is formed with or attached to the hood30; however other locations for the air intake plenum24are contemplated. Intake airflow travels from the opposing intake inlets32to a central opening34in a lower surface37of the air intake plenum24. The exact configuration of the air intake plenum24can vary from that which is shown.

As shown inFIGS. 2 and 3, the hood30and the associated air intake plenum24are together movable between a closed position shown inFIG. 2and an open position shown inFIG. 3. The hood30is pivotable about a hinge31located at the front of the vehicle22; however other types of movable connections between the hood30and the vehicle22can and often are employed. The hood30typically is moved into the open position during periods of non-use and sometimes during start-up of the vehicle22. The hood30typically is in the closed position during travel of the vehicle22.

According to the present disclosure, the air induction system20includes a device21for connecting the air from the air intake plenum24to the air cleaner26in a manner that provides a long-term sealing joint and/or protects the air cleaner26from intrusion of environmental elements such as water and/or dust. The particular configuration of the device21can vary, examples of which are shown inFIGS. 2-7, 8-11, 12, and 13.

FIGS. 2-7depict an example of a device21A having a bellows36that connects the air intake plenum24to the air cleaner26when the air intake plenum24is in the closed position. The bellows36is made of a resilient flexible material, such as rubber and/or the like, wherein under pressure the bellows36can be compressed into a compressed position and then will expand back under power of its own resiliency towards an expanded position when the pressure is released. The bellows36is axially elongated and has an upstream first end38that is configured to seal with the air intake plenum24and a downstream second end40that seals with the air cleaner26. More specifically, the bellows36has an upper mating surface42that sealingly abuts against a lower mating surface37of the air intake plenum24when the hood30of the vehicle22is moved into the closed position. When the hood30is moved into the open position, the lower mating surface37of the air intake plenum24and mating surface42of the bellows36are separated, thereby opening the seal. The shape and construction of the mating surfaces37and42can vary from that which is shown as long as an effective seal is created between the bellows36and the air intake plenum24when the hood30is moved into the closed position. In this example, the mating surface42is relatively flat and square-shaped, and has a plurality of perimeteral sealing ribs44for encouraging the noted sealing contact between the mating surfaces42and37.

The bellows36has a plurality of corrugations46along its length. An axially lowermost corrugation46is received in a mating channel48of a static base member50connected in sealing relationship with an inlet opening of the air cleaner26. Thus, the downstream second end40of the bellows36is sealed with the air cleaner26. The manner of connection between the bellows36and air cleaner26can vary from that shown and described as long as a seal is provided therebetween. A spring52is disposed in the bellows36and applies a biasing pressure on the bellows36that encourages sealing between the bellows36and the air intake plenum24and between the bellows36and the air cleaner26. The spring52has convolutions54that optionally can be interdigitated amongst the plurality of corrugations46. The spring52has opposite first and second ends56,58. The first end56is engaged in a groove60on an internal surface62of one of corrugations46of the bellows36. The opposite second end58abuts against an outer surface of the mating channel48on the base member50. The manner of connection between the spring52and bellows36can vary from that shown as long as the spring52effectively applies a bias force on the bellows36.

In some other examples, the orientation of the bellows36could be the opposite from that shown, such that the first end38of the bellows36remains connected to the air intake plenum24when the hood30is moved into the open position. In these examples the second end40of the bellows36can have a mating surface for mating with a compatible mating surface on the air cleaner26. In some examples, the orientation of the spring52could also be reversed, such that the first end56of the spring52abuts against an outer surface of a mating channel on a base member associated with the air intake plenum24and the second end58of the spring52is engaged in a groove60on an internal surface of one of corrugations of the bellows36. In some other examples, both of the first and second ends56,58of the spring52can be engaged in grooves on internal surfaces of corrugations of the bellows36.

FIGS. 2, 5 and 7depict the situation where the hood30and its air intake plenum24are in the noted closed position.FIGS. 3, 4 and 6depict the situation where the hood30and its air intake plenum24are in the noted open position. As shown by comparison of these figures, the spring52and bellows36are axially compressed when the hood30and air intake plenum24are in the noted closed position. The spring52and bellows36are not axially compressed, or are extended, when the hood30and the air intake plenum24are in the noted open position. The natural resiliency of the bellows36and the resiliency or spring force of the spring52both operate to bias the bellows36into the extended position shown inFIGS. 3, 4 and 6when the hood30is moved into the open position. Engagement between the lower mating surface37of the air intake plenum24and the mating surface42of the bellows36, including downward movement of the hood30into the position shown inFIG. 2, compresses the bellows36into the compressed state shown inFIGS. 2, 5 and 7. In the closed position, the combined biasing forces of the spring52and the natural resiliency of the bellows36operates to maintain effective sealing pressure over time, even when the resiliency of the bellows36itself does not provide an effective seal. Therefore rise of atmospheric air intake temperature can be better controlled.

The device21A shown inFIGS. 2-7also has a shield64A that at least partially covers the upstream first end38of the bellows36, thereby limiting intrusion of environmental elements to the air cleaner26. The shield64A covers the upstream first end38to a greater degree when the hood30and air intake plenum24are in the open position, shown inFIG. 3, than when the hood30and air intake plenum24are in the closed position, shown inFIG. 2. That is, the shield64A is configured such that a first axial, perimeteral cross-sectional area for intake airflow through the bellows36is defined when the bellows36is compressed into the compressed state shown inFIGS. 5 and 7and a smaller, second axial, perimeteral cross-sectional area for intake airflow through the bellows36is defined when the bellows36is in the extended state shown inFIGS. 4 and 6. Thus the shield64A is configured to block inflow of environmental elements, such as rain water, into the bellows36when the hood30and air intake plenum24are in the open position shown inFIG. 3. The shield64A is also configured to block inflow of environmental elements such as rain water to the bellows36when the hood30and air intake plenum24are in the closed position. However the shield64A blocks inflow of environmental elements such as rain water to the bellows36to a greater degree when the hood30and air intake plenum24are in the open position then when the hood30and air intake plenum24are in the closed position.

In this example, the shield64A is fixed to the inlet on the air cleaner26and remains stationary with respect to the air intake plenum24and hood30as the air intake plenum24and hood30move between the open and closed positions. As noted hereinabove, the bellows36is forced into the compressed state shown inFIG. 7when the air intake plenum24is in the closed position and the bellows36is biased into an extended state shown inFIG. 6when the air intake plenum24is in the open position. As shown inFIG. 7, the bellows36is elongated and defines an interior channel66that extends between an upstream first opening68at the upstream first end38and a downstream second opening70at the downstream second end40. As shown inFIGS. 6 and 7, the shield64A includes an axial support member72that axially extends along the interior channel66. A radial cover plate74radially extends from the axial support member72. The configuration of the axial support member72can vary from that which is shown. In this example, the axial support member72includes a center post76that has a plurality of throughholes78that allow intake of airflow therethrough from upstream to downstream. A plurality of radially extending ribs80support the center post76in the interior channel66. The radial cover plate74has a radially outer edge82that is located adjacent an inner perimeteral surface84of the bellows36when the air intake plenum24is in the noted open position, seeFIGS. 3 and 6, thereby reducing or eliminating inflow of environmental elements such as rain water through the bellows36.

In the example shown inFIGS. 2-7, the radially outer edge82has a bottom portion86that seals with the bellows36when the hood30and air intake plenum24are in the open position, shown inFIGS. 3 and 6. The radially outer edge82of the cover plate74is axially spaced apart from the first end38of the bellows36when the air intake plenum24is in the closed position so as to define a first perimeteral gap G1shown inFIGS. 5 and 7through which intake airflow passes to the air cleaner26. As explained further herein below, the gap G1also exists in the embodiment shown inFIGS. 8 and 9. A radial extension plate88is axially spaced apart from the radial cover plate74so as to define a second perimeteral gap G2therebetween that is axially spaced apart from the first perimeteral gap G1through which intake airflow passes to the air cleaner26. The second perimeteral gap G2continuously allows intake airflow to pass into the bellows36via a hole39in the cover plate74, when the air intake plenum24is moved between the open and closed positions. The size of the shield64A can be selected so that the gap G2is big enough to allow sufficient airflow during idle conditions of the engine28and the combined gaps G1and G2are big enough to allow maximum speed operation of engine28. An extension member90supports the radial extension plate88apart from the radial cover plate74. The extension member90includes a center post92that has a plurality of throughholes94that allow intake airflow into the interior channel66.

FIGS. 8-11depict another example of a device21B for connecting the air intake plenum24to the air cleaner26.FIGS. 8 and 9show the device21B when the hood30and air intake plenum24are in the closed position.FIGS. 9 and 10show the device21B when the hood30and air intake plenum24are in the open position. In this example, the bellows36and spring52are configured similar to the examples shown inFIGS. 1-7. The shield64B has a different configuration from the shield64A shown inFIGS. 1-7. In this example, the shield64B does not include the radial extension plate88and extension member90. Also, the cover plate74does not include the noted hole39. The radial cover plate74has the noted radially outer edge82which, as shown inFIGS. 10 and 11, is located adjacent to the inner perimeteral surface84of the bellows36when the air intake plenum24is in the open position. In this example, the radially outer edge82is axially flush with the first opening68at the first end38of the bellows36when the air intake plenum24is in the open position. The radially outer edge82is axially spaced apart from the first end38of the bellows36when the air intake plenum24is in the closed position, as shown inFIGS. 8 and 9, so as to axially define a first perimeteral gap G1through which the intake airflow passes to the air cleaner26. A drain valve98is provided in the bellows36. The drain valve98is a conventional one-way valve formed in one of the plurality of corrugations46and drains rainwater that enters the bellows36. The drain valve98can be necessary in examples where the radially outer edge82of the radial cover plate74does not seal with the inner perimeteral surface84of the bellows36, thus draining environmental elements, such as rainwater, that passes into the interior channel66of the bellows36between the radial outer edge82and the inner perimeteral surface84. The location of the drain valve98can vary from that shown. For example the drain valve98can instead be located in base member50.

FIG. 12depicts another example of a device21C for connecting the air intake plenum24to the air cleaner26when the air intake plenum24is in the closed position. In this example, a magnet100is provided on the outer perimeter102of the bellows36. The type of magnet can vary and could be a permanent magnet or an electromagnet. A metal ring104is disposed in the air cleaner26. The magnet100is attracted to the metal ring104and thereby creates a perimeter seal between the bellows36and the air cleaner26. In another example, the bellows36and air cleaner26can comprise a North and South magnet so that the bellows36and air cleaner26are magnetically attracted to each other, thereby forming a perimeteral seal therebetween.

FIG. 13depicts another example of a device21D for connecting the air intake plenum24to the air cleaner26when the air intake plenum24is in the closed position. A pressurized inflatable ring110is disposed in a perimeteral groove112on the outer perimeter102of the bellows36. Inflation of the ring110via a source of pressurized air114expands the inflatable ring110and thus presses radially inwardly into the perimeteral groove112onto the outer perimeter102of the bellows36, thus pressing the outer perimeter102of the bellows36against the groove112in the housing114of the air cleaner26, thus creating a perimeteral seal between the bellows36and the air cleaner26. The type of source of pressurized air114can vary and can include, for example a pump.

In the present disclosure, certain terms have been used for brevity, clearness and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes only and are intended to be broadly construed. The different systems and methods described herein may be used alone or in combination with other systems and methods. Various equivalents, alternatives, and modifications are possible within the scope of the appended claims. Each limitation in the appended claims is intended to invoke interpretation under 35 USC §112, sixth paragraph, only if the terms “means for” or “step for” are explicitly recited in the respective limitation.