Valve assembly for preventing liquid ingestion and methods

Information

  • Patent Grant
  • 6209559
  • Patent Number
    6,209,559
  • Date Filed
    Tuesday, December 7, 1999
    25 years ago
  • Date Issued
    Tuesday, April 3, 2001
    23 years ago
Abstract
A valve assembly includes a housing and a float. The housing is constructed and arranged to inhibit movement of the float between a resting position to a position where it is situated in its valve seat, unless a selected liquid volume within the valve housing is attained. In one embodiment, a series of projection members or rings creates a tortuous path, such that there is no clear path for the float to reach the valve seat. In another embodiment, vacuum pressure is created between the float and its cup support. Still other embodiments utilize magnets, springs, linkages, and bent wires. Methods for preventing liquid ingestion into an engine through an air intake are also provided.
Description




FIELD OF THE INVENTION




This invention is directed to valve assemblies and air cleaners. More specifically, this invention is directed to a valve assembly for an engine air cleaner to prevent the ingestion of liquid into an engine through the air intake of the engine.




BACKGROUND OF THE INVENTION




Certain types of motor vehicles such as four wheel drive sport utility vehicles, light trucks, agricultural vehicles, watercraft, all-terrain, military vehicles and mining vehicles at times may be operated in off-road areas. Such vehicles can typically have engine sizes of under 1 liter to more than 20 liters piston displacement, and horsepower of less than 10 to more than 1500 (7.5-1118 kw). In this off-road environment, vehicles may encounter liquid obstacles, such as rivers, streams, water-filled ditches, or water-filled ravines.




Crossing these liquid obstacles can have serious consequences if the depth of the liquid is deeper than the height of the engine air intake on the vehicle. If more than just a small amount of water enters the engine air intake, engine damage may occur. Such damage may include hydrostatic lock. If an engine cylinder gets more water in it than its compressed volume, the engine stops instantly and major engine damage, such as bent piston connecting rods may result.




SUMMARY OF THE INVENTION




In one aspect, the invention is directed to a valve assembly for preventing liquid ingestion into an engine through the air intake of the engine. The valve assembly is configured and arranged to prevent the valve assembly from closing when conditions do not warrant its closing, due to vibration and bounce, for example.




In one embodiment, the valve assembly includes a housing defining an open interior, an inlet port, a valve seat having an outlet port extending therethrough and a float support region. The inlet port and the outlet port are in fluid communication with the open interior. The valve assembly includes a float within the housing. The float is movable between first and second positions along a float path. The first position includes the float being positioned within the float support region of the housing. The second position includes the float positioned within the valve seat to obstruct the outlet port in response to a selected liquid volume within the housing. The housing is constructed and arranged to inhibit movement of the float along the float path to the second position, unless the selected liquid volume within the housing is attained.




In one embodiment, the housing comprises projection members constructed and arranged to obstruct the float path. For example, the projection members include first and second eccentric, spaced rings positioned within the housing along the float path. In this manner, there is no clear path for the float to follow, in order to reach the valve seat in the second position.




In another embodiment, the float comprises a spherical ball, and the housing includes a cup member for holding the ball in the float support region. The cup is constructed and arranged to retain the float within the cup by vacuum pressure.




In another embodiment, the housing includes a magnet in the float support region, and the float includes a metallic material attracted to the magnet.




In another aspect, the invention is directed to an air cleaner assembly comprising an air cleaner housing having an air inlet and an air outlet. A filter element is positioned within the housing, downstream of the inlet and upstream of the outlet. A valve assembly is positioned downstream of the filter element within the air cleaner housing. The valve assembly includes a float and a valve seat. The valve seat circumscribes the air outlet. The float is movable between first and second positions along a float path. The first position includes the float being positioned away from the valve seat. The second position includes the float being positioned within the valve seat to obstruct the air outlet in response to a selected liquid volume within the housing. The air cleaner housing is constructed and arranged to inhibit movement of the float along the float path to the second position, unless the selected liquid volume within the housing is attained.




In one example, the valve assembly includes a cylindrical tube holding the float in the first position. The cylindrical tube is, for example, lined with obstruction members projecting inwardly to inhibit float movement along the float path.




In another arrangement, the valve assembly includes a cup member for holding the float in the first position. The cup is constructed and arranged to retain the float within the cup by vacuum pressure.




Methods for preventing liquid ingestion into an engine through the air intake of the engine are provided. In one method, a valve assembly is provided upstream of the engine. The valve assembly has a float and a valve seat. The float is movable along a float path between a first position away from the valve seat and a second position blocking the valve seat. Movement of the float is inhibited along the float path to prevent movement of the float to the second position, unless a selected liquid volume within the valve assembly is attained. Example methods include constructions as described herein.




It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention, as claimed.




The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate example embodiments of the invention and together with the description, serve to explain the principles of the invention.











IN THE DRAWINGS





FIG. 1

is a schematic, side elevational view of an embodiment of an air cleaner housing, partially broken away depicting a filter element, in which a valve assembly of the present invention may be utilized.





FIG. 2

is a perspective view of an embodiment of an outlet chamber of the air cleaner housing depicted in

FIG. 1

, usable to house a valve assembly in accordance with principles of the present invention.





FIG. 3

is a schematic, cross sectional view of the embodiment of the outlet housing depicted in

FIG. 2

, and showing a valve assembly, in accordance with the principles of the present invention.





FIG. 4

is a front side elevational view of one embodiment of the valve assembly, depicted in

FIG. 3

, in accordance with principles of the present invention.





FIG. 5

is a schematic, top plan view of a ring construction usable in the valve assembly, and depicted in FIG.


3


.





FIG. 6

is a schematic, perspective view of a second embodiment of a valve assembly usable in the air cleaner housing of

FIG. 1

, in accordance with principles of the present invention.





FIG. 7

is a schematic, front side elevational view of a third embodiment of a valve assembly usable in an air cleaner housing depicted in

FIG. 1

, in accordance with principles of the present invention.





FIG. 8

is a schematic, side elevational view of an alternative embodiment of a float construction, usable in the valve assemblies in accordance with principles of the present invention.





FIG. 9

is a schematic, side elevational view of another alternative embodiment of a float construction usable in valve assemblies, in accordance with principles of the present invention.





FIG. 10

is a schematic, side elevational view of another alternative embodiment of a float construction, usable in valve assemblies, in accordance with principles of the present invention.





FIG. 11

is a schematic, side elevational view of another alternative embodiment of a float construction, usable in valve assemblies, in accordance with principles of the present invention.





FIG. 12A

is a schematic, partial cross-sectional view of another embodiment of a valve assembly usable with the air cleaner housing depicted in

FIG. 1

, depicted in an open position, in accordance with principles of the present invention.





FIG. 12B

is a schematic, partial cross-sectional view of the valve assembly of

FIG. 12A

depicted in a closed position, in accordance with principles of the present invention.





FIG. 13A

is a schematic, partial cross-sectional view of another embodiment of a valve assembly usable with the air cleaner housing depicted in

FIG. 1

, depicted in a closed position, in accordance with principles of the present invention.





FIG. 13B

is a schematic, partial cross-sectional view of the valve assembly of

FIG. 13A

depicted in a closed position, in accordance with principles of the present invention.





FIG. 14

is a schematic, partial cross-sectional view of another embodiment of a valve assembly usable with the air cleaner housing depicted in

FIG. 1

, in accordance with principles of the present invention.





FIG. 15

is a schematic, partially cross-sectional, partially broken away view of an alternative embodiment of a valve assembly, similar to that depicted in

FIG. 4

, and showing the valve assembly in an open orientation, in accordance with principles of the present invention.





FIG. 16

is a schematic, partially cross-sectional, partially broken away view of the embodiment of the valve assembly depicted in

FIG. 15

, and showing the valve assembly in a closed position, in accordance with principles of the present invention.





FIG. 17

is a schematic view of the air cleaner depicted in

FIG. 1

upstream from an engine.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




In

FIG. 1

, an air cleaner is shown generally at


20


. Air cleaner


20


may be used to filter and clean air as it is being drawn into an engine for combustion purposes. Air cleaner


20


is suitable for engines having sizes with a piston displacement in a range from about 2-8 liters, and horsepower of 100-300 horsepower (about 75-224 kw). Air cleaner


20


includes a housing


21


, an air inlet


22


, and an air outlet


23


. Also within housing


21


is a filter element


24


. Filter element


24


includes a media construction for cleaning and filtering particles from the air, to ensure only clean air is vented into the engine intake. Filter element


24


may include a variety of media constructions and material. In the particular embodiment illustrated, filter element


24


is a rolled, corrugated cellulose media, having an oval-shaped profile. Media constructions of this type are described further in commonly assigned and co-pending U.S. patent application Ser. No. 08/639,371, filed on Apr. 26, 1996, now U.S. Pat. No. 5,820,646, and incorporated by reference herein. Also shown in

FIG. 1

, housing


21


defines an aperture


25


in the inlet region


26


of the housing


21


. As will be described further below, aperture


25


functions as a liquid or water drainage hole.




Inlet


22


is positioned upstream of filter element


24


. Filter element


24


is positioned upstream of outlet


23


. In operation, air cleaner


20


is oriented upstream of an engine. Air is taken through inlet


22


and then passes through element


24


. Element


24


cleans or filters particles from the air. The air then passes downstream to outlet assembly


27


, and then through outlet member


23


. The cleaned air then, typically, passes into the engine for combustion. In

FIG. 17

, an engine


300


is illustrated schematically downstream of an air cleaner


299


. The air cleaner


299


may be of the type, for example, illustrated at


20


in FIG.


1


. Cleaned air


302


is shown passing from the air cleaner


299


to the engine


300


.




In reference now to

FIG. 2

, a perspective view of outlet assembly


27


is illustrated. Outlet assembly


27


for example includes a first construction


28


and an outlet tube construction


29


. First construction


28


is oriented for engagement with element section


30


,

FIG. 1

, of housing


21


. That is, after air flows through element


24


, it passes into first construction


28


. Outlet tube construction


29


is oriented in extension from first construction


28


and projects or extends from first construction


28


. Outlet tube construction is part of a valve assembly


40


, described further below.




In reference now to

FIG. 3

, one example outlet assembly


27


is shown in cross-sectional view. As can be seen in

FIG. 3

, outlet assembly


27


houses or contains valve assembly


40


within it. Valve assembly


40


is conveniently located within outlet assembly


27


, such that no additional parts or accessories need to be installed within what may sometimes be a very confined region under the hood of a sports utility vehicle. Valve assembly


40


is, for example, located just upstream of the air intake to the engine, in order to prevent the ingestion of water or other liquid into the engine through the air intake.




In general, one example valve assembly


40


includes a housing construction


42


and a float


44


. The example housing construction


42


defines an open interior


45


, an inlet port


46


, a valve seat


47


defining an outlet


48


extending therethrough, and a float support region


50


.




To summarize operation of the example valve assembly


40


, when liquid, such as water, fills valve assembly


40


by entering through inlet port


46


, float


44


moves or floats with the level of liquid from the float support region to the valve seat


47


. When seated within valve seat


47


, float


44


blocks outlet port


48


. This blockage prevents liquid from passing through outlet tube


23


. This also blocks the intake of air into an engine, which shuts the engine down and prevents the water or liquid from being ingested. When the liquid level drops, float


44


leaves valve seat


47


, and the engine may be restarted without damaging the engine. As shown in

FIG. 1

, aperture


25


is provided to function as a liquid drain hole in the inlet region


26


, which is typically the lowest point of the air cleaner


20


when mounted in a vehicle, to allow water or liquid to drain out of the air cleaner


20


.




Valve assembly


40


also includes structure to inhibit or prevent the valve outlet port


48


from closing, when conditions do not warrant it to be closed. In other words, structure is provided in valve assembly


40


to inhibit, impede, or prevent float


44


from becoming seated onto valve seat


47


, unless the appropriate liquid level within first construction


28


and housing construction


42


is attained. This structure is provided because if outlet port


48


is blocked, the engine will shut down. For example, engine shutdown is desired only if there is a danger of liquid being drawn into the engine through the air intake. Example constructions to inhibit movement of the float


44


are described herein below.




In reference now to

FIG. 4

, valve housing construction


42


is shown in front side elevational view. One example housing construction


42


shown is a tubular, or cylindrical extension


51


having a bottom or first end


52


and an opposite top or second end


53


. Adjacent to first end


52


of extension


51


is wall member


54


. Wall member


54


functions to contain float


44


(

FIG. 3

) within the float support region


50


of the valve assembly


40


. Wall member


54


functions as a baffle to shelter float


44


from air flow as it flows from element section


30


(

FIG. 1

) to outlet


23


(FIG.


3


). Stated another way, baffle or wall member


54


blocks air flow from hitting float


44


when float


44


is in float support region


50


(

FIG. 3

) so that air flow does not lift float


44


and position it into valve seat


47


(FIG.


3


). Wall member


54


defines a drainage aperture


55


therein. Drainage aperture


55


allows liquid to drain from float support member


50


.




Adjacent to wall member


54


, valve housing construction


42


can define a cut-away or open window region


56


. Window region


56


defines valve inlet port


46


. Window region


56


is constructed and arranged to allow for air flow to pass therethrough, but it is small enough to prevent float


44


from passing therethrough. That is, a smallest dimension across float


44


is larger than any largest dimension across window region


56


. This is to prevent float


44


from leaving housing construction


42


and traveling to other regions of air cleaner


20


. Therefore, the housing construction


42


, including the size and shape of window region


56


, operates as a cage assembly, in that it is configured and arranged to keep float


44


within housing construction


42


and on its float path between the float support region


50


and valve seat


47


.




Still referring to

FIG. 4

, housing construction


42


can define a tubular or cylindrical outlet tube


58


at the second end


53


. Outlet tube


58


has a largest cross-sectional inside dimension (diameter) that is, for example, smaller than the largest cross-sectional inside dimension (diameter) of extension


51


at tube region


60


. Due to the differences in inside diameters between tube region


60


and outlet tube


58


, valve seat


47


(

FIG. 3

) is formed at the transition region therebetween. Wall member


54


and tube region


60


have a largest cross-sectional inside dimension (diameter) that is larger than a largest cross-sectional outside dimension of float


44


. If using a spherical float


44


, the largest cross-sectional dimension inside (diameter) of outlet tube


58


is, for example, smaller than the largest cross-sectional diameter of float


44


. In this way, float


44


is allowed to move between float support region


50


and valve seat


47


, and block outlet port


48


when float


44


is seated against valve seat


47


(FIG.


3


). If the float


44


is shaped in something other than a spherical shape, one skilled in the art will appreciate that the relative relationship between the dimensions of the float


44


and the outlet tube


58


is adjusted such that the float


44


will be permitted to move between the float support region


50


and valve seat


47


and block the outlet port


48


when the float


44


is seated against the valve seat


47


(FIG.


3


).




Referring again to

FIG. 3

, float


44


is shown in cross-section. In the example shown, float


44


includes a symmetrical construction, such that the orientation of float


44


is irrelevant when it is seated within valve seat


47


. In the embodiment illustrated, float


44


is a spherical ball


62


. For example, ball


62


comprises a material having a density less than that of water, such that it will float in water. One construction of ball


62


may be polypropylene, 0.09 inches (about 2.3 mm) thick. The diameter of ball


62


may be, for example, from about 1-6 inches (about 25.4-152.4 mm), for example, 2.245-2.75 inches (about 57-69.9 mm), or for example, about 2.5 inches (about 63.5 mm). Ball


62


, for example, if having a diameter of 2.5 inches (about 63.5 mm), would be hollow and weigh no more than about 30 grams.




Still in reference to

FIG. 3

, valve housing construction


42


is constructed and arranged to inhibit movement of the float


44


along the float path to a position where it is seated within valve seat


47


, unless a selected liquid volume within the housing is attained. That is, unless liquid fills the interior of valve housing construction


42


, housing construction


42


includes structure to prevent the float


44


from being seated within valve seat


47


.




As embodied herein, one example valve housing construction


42


comprises projection members


64


,


65


constructed and arranged to obstruct the float path. As used herein, the term “float path” refers to the region between first end


52


of float support region


50


and valve seat


47


. In the

FIG. 3

embodiment, the float path is generally a linear configuration. However, in other embodiments,

FIG. 6

for example, the float path is non-linear and may be curved.




For example, projection members


64


,


65


function to interfere with float


44


as it moves from a resting position in float support region


50


and against the wall


32


of outlet assembly


27


.

FIG. 3

shows float


44


in a resting position. In the resting position, float


44


is, for example, within float support region


50


and touches and engages wall


32


. It should be understood, however, that a variety of resting positions are contemplated and can include many positions where the float


44


is not seated in valve seat


47


and where float


44


is not within the float support region


50


.




While a variety of working embodiments are contemplated herein, in the particular embodiment illustrated in

FIG. 3

, projection members


64


,


65


comprise first and second rings


66


,


67


. First and second rings


66


,


67


are, for example, eccentrically shaped and eccentrically aligned.




Turning now to

FIG. 5

, second ring


67


is schematically illustrated in top plan. The example ring


67


shown includes an inner rim


68


and an outer rim


69


. Inner rim


68


defines a circular diameter of about 2.51 inches, specifically, about 2.505 inches. Outer rim


69


defines a circular diameter of about 2.9 inches. As also shown in

FIG. 5

, the circumferential region defined between inner rim


68


and outer rim


69


varies in width between wide portion


70


and narrow portion


71


. The centers of circles defined by inner rim


68


and outer rim


69


are, for example, co-linear and spaced from each other a distance


72


of about 0.10 inches (about 2.5 mm). Second ring


67


defines a cross-sectional thickness of about 0.06 inches (about 1.5 mm).




In some constructions, the first ring


66


is analogously constructed as second ring


67


. However, the diameter of the outer rim of first ring


66


is about 2.94 inches (about 74.7 mm).




Attention is again directed to FIG.


3


. Note that first and second rings


66


and


67


are, for example, oriented relative to each other such that wide portion


70


of second ring


67


is co-linearly aligned with narrow portion


73


of first ring


66


. Similarly, narrow portion


71


of second ring


67


is aligned with wide portion


74


of first ring


66


. In this manner, the centers defined by each respective inner rim of first and second rings


66


,


67


are not coaxially aligned. This creates a tortuous, obstructed path for float


44


.




In general, it has been found that the preferred first and second rings


66


,


67


will have offset centers, each of the respective centers being defined by each respective inner rim of the first and second rings


66


,


67


. The amount of offset depends on factors such as: the vertical distance between inside surfaces of each of the rings


66


,


67


; the cross-sectional thickness of each of the rings


66


,


67


; and the diameter of the float


44


. For example, in the

FIG. 3

embodiment, the vertical distance between rings


66


,


67


is about 1.03 inches (about 26.2 mm). The cross-sectional thickness of each of the rings


66


,


67


is about 0.06 inches (about 1.5 mm). The diameter of the float


44


is about 2.5 inches (about 63.5 mm). For these dimensions, an offset between rings


66


,


67


is, for example, about 0.10 inch (about 2.5 mm).




Other dimensions which may be used for constructions herein are described below in Table 1.
















TABLE 1










Ring




Float





Ring Inside






Vertical Distance




Thickness




Diameter




Offset




Diameter











at least 1.03 in.




0.06 in.




2.500 in.




0.10 in.




2.505 in.






(about 26.2 mm)




(about 1.5




(about 63.5




(about 2.5




(about 63.6







mm)




mm)




mm)




mm)






at least 1.19 in.




0.06 in.




2.500 in




0.38 in.




2.505 in.






(about 30.2 mm)




(about 1.5




(about 63.5




(about 9.5




(about 63.6







mm)




mm)




mm)




mm)






at least 1.03 in.




0.06 in.




2.750 in.




0.20 in.




2.755 in.






(about 26.2 mm)




(about 1.5




(about 69.9




(about 5.1




(about 70







mm)




mm)




mm)




mm)






at least 1.19 in.




0.06 in.




2.250 in.




0.38 in.




2.255 in.






(about 30.2 mm)




(about 1.5




(about 57.2




(about 9.7




(about 57.3







mm)




mm)




mm)




mm)






at least 0.90 in.




0.06 in.




2.250 in.




0.20 in.




2.255 in.






(about 22.9 mm)




(about 1.5




(about 57.2




(about 5.1




(about 57.3







mm)




mm)




mm)




mm)














One preferred relationship is between the diameter of the float


44


and the inside diameter of the rings


66


,


67


. It has been found that if the inside diameter of the rings


66


,


67


is, for example, about 0.005 in. (about 0.13 mm) greater than the diameter of the float


44


, it leads to a convenient, preferred arrangement.




A tortuous, obstructed path for float


44


is created by arrangements of the rings


66


,


67


as described herein. For example, if vibration causes float


44


to move from its resting position shown in

FIG. 3

to pass through first ring


66


, it bumps into the circumferential band


75


of second ring


67


. This prevents float


44


from traveling any further toward the valve seat


47


. However, if liquid begins to fill housing construction


42


, float


44


will float on the surface of the liquid and rise as the level rises, where it will easily travel between first and second rings


66


,


67


.




While the embodiment of

FIG. 3

shows rings


66


,


67


radially lining the cylindrical tube of wall member


54


, it should be understood that other operative embodiments are contemplated. For example, first and second rings


66


,


67


need not be complete rings. Instead, they may be a series of projections or studs, non-joined to one another.




In certain example constructions, housing construction


42


comprises a unitary, molded construction made of plastic. Rings


66


,


67


are also plastic, and are secured to the interior of wall member


54


through standard techniques, such as adhesive bonding. Rings


66


,


67


may also be molded as part of the housing construction


42


.




In other embodiments, housing construction


42


may be a wire cage. The wire cage can include wire rings in place of the rings


66


and


67


. The wire cage is bent, such that the rings are not coaxially aligned. That is, the cage is bent in a non-linear or curved configuration. This provides an offset between the rings. If vibration or bounce occurs, the float will not have a clear path to its valve seat, due to the curved configuration of the wire cage and the placement of the wire rings. In another embodiment, instead of rings


66


,


67


, horizontal partitions with offset holes can be used.




Turning again to the embodiment shown in

FIG. 3

, one example valve seat


47


is illustrated as including a flexible seal member


76


. For example, seal member


76


comprises a circular ring with opposite first and second surfaces


77


,


78


. In

FIG. 3

, note that seal member


76


is spaced from the wall of the outlet tube construction


29


to form a gap


79


therebetween. The gap


79


allows the seal member


76


to flex within gap


79


when float


44


engages it. For example, when float


44


engages seal member


76


, a seal is formed between the seal member


76


and the float


44


to prohibit the passage of fluid therebetween. Further, the seal member


76


is flexible such that it helps to form the seal with the float


44


, yet it prevents float


44


from sticking in the seal member


76


. In certain example arrangements, the seal member


76


can have a thickness of about 0.06 inches. (about 1.5 mm), and an inner diameter for example the same as the inner diameter of the tube construction


29


. In one example arrangement, the inner diameter of the seal member


76


is about 2.38 inches (about 6 cm). For example, the seal member


76


and the outlet tube construction


29


form gap


79


having a height of about 0.06 inches (about 1.5 mm).




In operation, during normal conditions when air cleaner


20


is above any level of liquid, float


44


is held within float support region


50


. Air is being filtered through air cleaner


20


by passing from inlet


22


, through filter element


24


, into outlet assembly


27


, through inlet port


46


, out through outlet tube


23


, and into an engine. As the vehicle, and, therefore the air cleaner


20


, move, the air cleaner


20


may be subject to significant vibration due to bumps in the road, uneven road conditions, etc. As air cleaner


20


vibrates or bounces, float


44


is maintained within float support region


50


and away from valve seat


47


, due to rings


66


,


67


. That is, float


44


may be jarred from, jiggled, or forced away from engaging wall


32


and wall


54


, but bump up against ring


66


and then bounce to bump up against ring


67


. Due to the relative positioning of rings


66


and


67


and their orientation with respect to each other, float


44


is impeded from advancing further toward valve seat


47


. If the vehicle is driven into deep liquid or water to a level which is above the inlet


22


of housing


21


, the liquid enters inlet


22


, travels through filter element, and eventually reaches outlet assembly


27


. As the level of liquid begins to rise within outlet assembly


27


and valve assembly


40


, float


44


floats on the surface of the water or liquid. As the liquid rises, float


44


floats on the surface of the liquid through the ring


66


and the ring


67


, until it eventually sits within valve seat


47


to block the air outlet


23


. As the liquid level gets the float


44


close to the outlet


23


, air flow forces, drag, and/or vacuum facilitate the float


44


seating quickly in the valve seat


47


to block the outlet


23


. When float


44


blocks air outlet


23


, the air intake to the engine is cut off, and the engine shuts down. Float


44


also prevents the liquid or water from being passed or sucked into the engine. Float


44


stays positioned in valve seat


47


until the liquid level falls, even if the engine is turned off. As the liquid level falls, for example, if the vehicle is pushed out of the region of high water, the liquid is allowed to drain through aperture


25


. The liquid does not become trapped within float support member


50


, because of drain aperture


55


. Therefore, the liquid or water is allowed to eventually drain through aperture


25


. Aperture


25


is generally the lowest part of the air cleaner


20


, when oriented on a vehicle. As the liquid level falls, the float


44


falls from within valve seat


47


. This permits the engine to again be started, where air is allowed to flow through the air cleaner and out through the outlet tube


23


into the engine.




Attention is now directed to FIG.


6


. In

FIG. 6

, a second embodiment of a valve assembly is depicted generally at


80


. In

FIG. 6

, the example valve assembly


80


includes a housing


81


. Housing


81


includes a float support region


82


, a cage region


83


and an outlet tube


84


. Outlet tube


84


defines an outlet aperture


85


and a valve seat


86


.




As can be seen in

FIG. 6

, the example outlet tube


84


includes an inner wall


88


tapered between a region of largest diameter at outlet aperture


85


to a region of smallest diameter at valve seat


86


. A spherical float


90


is shown seated within valve seat


86


.

FIG. 6

depicts float


90


in a position when liquid has filled the air cleaner housing, including the outlet assembly


27


, to cause float


90


to become removably lodged in or seated within valve seat


86


and block fluid flow through outlet aperture


85


.




The valve seat


86


can include a flexible seal member, analogous to that described at


76


in conjunction with FIG.


3


.




Still in reference to

FIG. 6

, float support region


82


comprises a cup


92


, for example. The example cup


92


shown is shaped and configured to snugly conform to the shape of spherical float


90


. Specifically, the particular cup


92


shown has a cross section which is generally U-shaped. For example, it includes a hemispherically shaped portion


94


. Hemispherically shaped portion


94


defines, at its lowest portion, an aperture


96


.




When float


90


is in its resting position, i.e. during normal engine operation and location above liquid levels, float


90


rests within cup


92


and against hemispherically shaped portion


94


. If liquid begins to fill housing


81


, float


90


will float at the surface of the liquid level out of cup


92


and be guided by cage region


83


into valve seat


86


.




The example cage region


83


functions to allow for the free passage of air through cage region


83


, while maintaining float


90


within its path between cup


92


and valve seat


86


. Cage region


83


, in this embodiment, comprises a plurality of elongate members


98


in extension between cup


92


and outlet tube


84


. In this example, there are four members


98


. In one example, extension members


98


are constructed of wire.


10


Aperture


96


operates as a drainage hole, in order to help drain liquid from housing


81


after liquid has entered housing


81


.




Valve housing


81


is constructed and arranged to inhibit movement of float


90


along its float path to the valve seat


86


, unless liquid fills the housing


81


. In the embodiment of

FIG. 3

, the example valve housing construction


42


included projection members or ring constructions. In the

FIG. 6

embodiment, float


90


is restrained by suction or vacuum pressure.




Specifically, the relationship between the inner diameter of the cup


92


, diameter of the float


90


, axial length of the cup


92


and weight of the float


90


are selected such that pneumatic dampening occurs.




In general, if the float


90


is shook or vibrated, the float


90


will move from the portion


94


within the cup


92


. As the float


90


moves axially along the cup


92


, the volume between the float


90


and the portion


94


increases. This increase in volume causes a pressure drop in the volume between the float


90


and portion


94


. The drop in pressure results in a pressure differential across the float


90


between the volume inside of the cup


94


(i.e., between the portion


94


and the float


90


) and the volume outside of the cup


92


. Specifically, the pressure within the cup


92


is less than the pressure outside of the cup


92


. This region of decreased pressure acts as vacuum to suck or draw the float


90


back toward portion


94


. In other words, as the float


90


moves away from portion


94


, the increase in volume (and thus the decrease in pressure) occurs faster than air can get into the volume between the float


90


and portion


94


, which results in a volume of decreased pressure below the float


90


(within cup


92


) as compared to above the float


90


(outside of cup


92


). The net decrease in pressure results in a vacuum, which acts to restrict movement of the float


90


toward the valve seat


86


.




Example constructions include the inner diameter of the cup being about 1.01-6.01 inches (about 25.7-152.7 mm), for example, about 2.25-2.75 inches (about 57.2-69.9 mm), and for example about 2.4 inches (about 61.0 mm). The outer diameter of float


90


is, for example, about 1-6 inches (about 25.4-152.4 mm), for example about 2.24-2.74 inches (about 56.9-69.6 mm), and for example about 2.39 inches (about 60.7 mm). Therefore, the ratio of the inner diameter of cup


92


to outer diameter of float


90


is about 1.004. That is, for example, the inner diameter of the cup


92


is no more than about 0.4% larger than the outer diameter of the float


90


.




In certain constructions, cup


92


has an axial length of about 1.55-6.05 inches (about 39.4-153.7 mm), for example, about 2.55-3.05 inches (about 64.8-77.5 mm), and, for example, about 2.7 inches (about 68.6 mm). Typically, float


90


is constructed of polypropylene material, weighs about 30 grams, and has a density less than one gram per cubic centimeter. Drainage aperture


96


typically has a diameter of, for example, about 0.06-0.12 inches (about 1.5-3.0 mm), and, for example, about 0.09 inches (about 2.3 mm). Thus, the ratio of the diameter of the drainage aperture


96


to the inner diameter of the cup


92


is about 0.038. That is, for example, the inner diameter of the cup


92


is about 26.67 times larger than the diameter of the drainage aperture


96


. Drainage aperture


96


cannot be made too large, or else it will destroy the suction or vacuum pressure induced between the wall of cup


92


and float


90


. That is, it will allow air to rush into the volume of the cup


92


below the float


90


as fast as the volume below the float


90


increases.




In certain constructions, the axial length of the cup


92


and the outer diameter of the float


90


are selected for certain, preferred applications. In one example construction, the axial length of the cup


92


is from ½ to 5 times the length of the outer diameter of the float


90


. In other words, the ratio of the axial length of the float


90


to the outer diameter of the float


90


is between 1:2 and 5:1. In one example construction, the ratio is 2.7:1.




In operation, during normal conditions when air cleaner


20


is above any level of liquid, float


90


is held within float support region


82


within cup


92


. Air is being filtered through air cleaner


20


by passing from inlet


22


, through filter element


24


, into outlet assembly


27


, through cage region


83


, out through outlet aperture


85


, and into an engine. As the vehicle, and therefore the air cleaner


20


, move, the air cleaner


20


may be subject to significant vibration due to bumps in the road, uneven road conditions, etc. As air cleaner


20


vibrates or bounces, float


90


is maintained within cup


92


, due to pneumatic dampening. That is, float


90


may be jarred from or forced away from inner wall of hemispherically shaped portion


94


, but due to the dimensional relationship between float


90


and cup


92


, suction is induced which keeps float


90


within cup


92


and away from valve seat


86


. If the vehicle is driven into deep liquid or water to a level which is above the inlet


22


of housing


21


, the liquid enters inlet


22


, travels through filter element


24


, and eventually reaches outlet assembly


27


. As the level of liquid begins to rise within outlet assembly


27


and valve assembly


80


, float


90


floats on the surface of the liquid. As the liquid rises, float


90


rises out of cup


92


, and, as the liquid level gets the float


90


close to the outlet


85


, air flow forces, drag, and/or vacuum facilitate the float


90


seating quickly to rest in valve seat


86


to block the outlet


85


. No vacuum or suction is induced between float


90


and cup


92


because of the float buoyancy. When float


90


blocks air outlet aperture


85


, the air intake to the engine is cut off, and the engine shuts down. Float


90


also prevents the liquid or water from being passed or sucked into the engine. As the liquid level falls, for example, if the vehicle is pushed out of the region of high water, the liquid is allowed to drain through aperture


96


and aperture


25


. As the liquid level falls, the float


90


falls from or becomes unseated from valve seat


86


. This permits the engine to again be started, where air is allowed to flow through the air cleaner and out through outlet aperture


85


into the engine.




Turning now to

FIG. 7

, another embodiment of a valve assembly is shown generally at


110


. In

FIG. 7

, valve assembly


110


is, in the example shown, constructed within an outlet assembly, such as outlet assembly


27


of air cleaner housing


21


. A float


112


moves between a float support region


113


and a valve seat


115


. When float


112


is positioned within valve seat


115


, (shown in phantom in FIG.


7


), float


112


blocks fluid flow through outlet tube construction


117


and outlet aperture


118


. As with the other embodiments described above, when float


112


is seated within valve seat


115


, it cuts off air flow into the engine, which causes the engine to shut down. This also prevents the intake of water or liquid into the engine.




Also shown in

FIG. 7

is a guidewire


120


. For example, guidewire


120


is oriented between the float support region


113


and the end


121


of outlet tube construction


117


. As such, guidewire


120


passes through the outlet port


122


and through the valve seat


115


, for example. The preferred float


112


includes an open-slotted portion


123


to slideably accommodate guidewire


120


. As such, guidewire


120


functions to guide float


112


between its resting position at float support region


113


along a path to valve seat


115


.




Note the shape of guidewire


120


. It is a nonlinear, curved shape. As such, it gives float


112


a nonlinear or curved float path. This nonlinear float path helps to prevent float


112


from being seated within valve seat


115


due only to vibration or shaking. As with the

FIG. 3

embodiment, this

FIG. 7

embodiment can include a seal ring or member at valve seat


115


, analogous to seal member


76


in FIG.


3


.




Valve assembly


110


is constructed and arranged to inhibit movement of float


112


along its float path to the valve seat


115


, unless a selected liquid volume within the housing is attained. As embodied herein, valve assembly


110


includes a magnet


125


located in the float support region


113


. Float


112


is constructed of a material attracted to magnet


125


, for example, a metallic material. The attractive force between the magnet


125


and the float


112


is strong enough to keep float


112


generally in its resting position against float support region


113


when the air cleaner is operated during normal conditions and above a level of liquid or water. The attractive force of magnet


125


is such that when liquid begins to fill the outlet assembly


27


, float


112


is dislodged from magnet


125


and allowed to rise with the level of liquid. Typically, attractive forces of magnets and floats are slightly less than the buoyancy of the float


112


. One useful attractive force between the magnet and the float


112


is about 70-90 grams, for a float with a weight of 30 grams and a diameter of 2.5 in.




Turning now to

FIGS. 8-11

, alternative shapes for float


112


are illustrated. The floats in

FIGS. 8-11

are more compact than the spherical design of the embodiments described above and may be easier to fit in the desired air cleaner to be used. The shapes in

FIGS. 8-11

are also inclined to minimize the forces of air flow being drawn through the air cleaner. As such, the shapes of

FIGS. 8-11

, can prevent the floats from being drawn to the valve seat merely by high velocity flow of air through the air cleaner. Note that in each of the float embodiments of

FIGS. 8-1

, a bottom surface is flat. Also, each of the float designs of

FIGS. 8-11

include circular tops for engagement with the valve seat. This is to ensure that float orientation within the valve seat is irrelevant.




In

FIG. 8

, a float


130


having a spherical-shaped top


131


for engaging the valve seat is shown.




In

FIG. 9

, a truncated or oblated cone-shaped float


132


is shown. Float


132


includes a flat surface at both end


133


, which does not engage the valve seat, and end


134


, which does engage the valve seat.





FIGS. 10 and 11

illustrate floats shaped with low profiles. In

FIG. 10

, float


135


has a partial spherical-shaped top. This can be seen at rounded curved surface


136


. Both the end


137


, which engages the valve seat, and the end


138


, which is opposite to end


137


, are flat.




In

FIG. 11

, a truncated cone-shaped float


139


is illustrated. Float


139


is analogous to float


132


(see FIG.


9


), but is shorter.




Attention is now directed to

FIGS. 12A and 12B

. In

FIGS. 12A and 12B

, another alternative valve assembly is shown generally at


140


. Valve assembly


140


includes a float


141


and a valve seat


142


. Float


141


, for example, includes an outlet sealing disk


143


. Outlet sealing disk


143


will serve to seat within valve seat


142


and block air flow and liquid intake through outlet tube


144


.




Float


141


is, for example, mounted to a hinged arm or linkage


145


. Linkage


145


locates the float


141


in its resting position or stored position on the bottom of the housing (

FIG. 12A

) and guides sealing disk


143


into the opening of the outlet tube


144


or valve seat


142


when liquid enters the region. Specifically, as liquid enters the region, float


141


starts to rise. As float


141


rises, it pushes the linkage


145


. As shown in

FIG. 12B

, the linkage


145


acts on and causes the sealing disk


143


to form a seal in the valve seat


142


. In this manner, the outlet tube


144


is sealed closed prior to the entire housing becoming full of liquid (FIG.


12


B). As the liquid in the housing starts to decrease, the float


141


drops. The drop of the float


141


pulls the linkage


145


downwardly, which pulls the sealing disk


143


out from within valve seat


142


and back to its resting position oriented over float


141


(FIG.


12


A). A magnet, such as that illustrated in

FIG. 7

, may be utilized to maintain the float


141


in its stored or resting position.





FIGS. 13A and 13B

show another embodiment of a valve assembly


150


. Valve assembly


150


is analogous to valve assembly


140


. Valve assembly


150


, for example, includes a float


153


and a valve seat


154


. The example float


153


includes an outlet sealing disk


156


. Outlet sealing disk


156


is analogous to sealing disk


143


(FIGS.


12


A and


12


B). A linkage


158


, for example analogous to linkage


145


, locates the float


153


in its resting position on the bottom of the housing (

FIG. 13A

) and guides sealing disk


156


to the valve seat


154


. An extension spring


152


, for example, cooperates with linkage


158


to provide a more positive seal. Specifically, in the example illustrated, spring


152


acts as an “over-center” spring. In the down position (FIG.


13


A), the spring


152


holds the float


153


down on the bottom of the housing. As liquid enters the region, the float


153


rises. As the float


153


rises, it acts on linkage


158


, which pushes on sealing disk


156


. When the spring


152


is moved over-center, it pulls the sealing disk


156


into the valve seat


154


(FIG.


13


B). To operate, the density of the float


153


is greater than the strength of the spring


152


.




Again, as with the

FIG. 12A

,


12


B embodiment and

FIG. 7

embodiment, a magnet may be used to inhibit movement of the float


153


from traveling to the valve seat


154


, unless water is in the region.





FIG. 14

shows another embodiment of a valve assembly


170


. The example valve assembly


170


includes a float


172


and a valve seat


174


. Float


172


is, for example, shaped and configured relative to valve seat


174


to fit within valve seat


174


and block fluid flow communication (i.e., either liquid flow or gas flow) between the volume


175


of outlet assembly housing


176


and outlet tube


178


.




Valve assembly


170


includes structure to guide the float


172


between a first position where the float


172


is positioned within the float support region of the outlet assembly housing


176


and a second position where the float


172


is positioned within the valve seat


174


to obstruct the outlet port


179


. While a variety of embodiments have been described thus far and are contemplated herein, in this particular embodiment, the structure, for example, includes a hinge and arm assembly


180


. The example hinge and arm assembly


180


comprises a hinge or plate


181


secured to outlet assembly housing


176


. Arms


182


are, for example, pivotally secured to hinge plate


181


. Arms


182


operate to secure the float


172


to the hinge plate


181


, and move the float


172


between its first and second positions. The phantom lines illustrate the float


172


moving from its first position (where it is resting against the outlet assembly housing


176


) toward the second position (where it is resting within the valve seat


174


).




An optional magnet


184


and metal plate


185


may be used to help inhibit movement of the float


172


along its float path to the second position, unless liquid starts to fill the volume


175


. If liquid does start to fill the volume


175


, the buoyancy of the float


172


will be sufficient to overcome the force between the magnet


184


and metal plate


185


. The float


172


will move along its float path toward the valve seat


174


, guided by the hinge and arm assembly


180


. As can be seen in phantom, the arms


182


permit the float


172


to rotate into a proper orientation to block the outlet port


179


.





FIG. 15

shows another embodiment of a valve assembly


200


. The example valve assembly


200


includes a float


201


and valve seat


202


. Float


201


is, for example, shaped and configured relative to valve seat


202


to block fluid flow communication (i.e., liquid or gas flow) between volume


203


of outlet assembly housing


204


and volume


205


within outlet tube


206


.




In the example shown, float


201


is cylindrical in shape with a circular cross section. The particular preferred float


201


shown in

FIG. 15

includes a support structure


208


and a sealing structure


209


. When sealing structure


209


engages valve seat


202


, it forms a seal


210


(

FIG. 16

) therebetween. The seal


210


blocks fluid flow into the volume


205


of the outlet tube


206


.




Referring again to

FIG. 15

, valve assembly


200


includes, for example, structure to guide the float


201


between open positions and a closed or sealed position. In the first or resting or open positions, the float


201


is not abutting or engaging the valve seat


202


. Typically, the float


201


will be positioned within a float support region


211


of the outlet assembly housing


204


when the valve assembly


200


is in open positions. While a variety of embodiments have been described thus far and are contemplated herein, in this specific embodiment, the structure for example includes a guidewire


212


. Guidewire


212


creates a torturous path for the float


201


between its resting position,

FIG. 15

, and its closed or sealed position, FIG.


16


. Specifically, guidewire


212


includes a non-linear extension shown generally at


214


. Non-linear extension


214


operates to introduce obstruction to the path between the resting position of float


201


and the closed or sealed position of float


201


. More specifically, non-linear extension


214


for example comprises bend or kink or projection


215


. Projection


215


resembles a smooth wave


216


, in the cross-sectional view shown in FIG.


15


.




For example, projection


215


interferes with float


201


as it moves from the resting position in float support region


211


to the closed or sealed position shown in FIG.


16


. For example, if vibration causes float


201


to move from its resting position shown in

FIG. 15

, it bumps into the projection


215


of the guidewire


212


. This prevents float


201


from traveling any further toward the valve seat


202


. If liquid begins to fill the housing construction, however, float


201


will float on the surface of the liquid and rise as the level rises, where it will easily travel over and traverse the projection


215


toward the valve seat


202


.




In the example shown, guidewire


212


extends between a bottom of valve assembly


200


and region within outlet tube


206


. For example, it should extend long enough such that the float


201


remains trapped in its guide path between its resting position in FIG.


15


and its closed position shown in FIG.


16


. In the specific preferred embodiment shown, the guidewire


212


extends into the volume


205


of the outlet tube


206


.




As can be seen in

FIGS. 15 and 16

, float


201


includes a guidewire housing slot


213


extending therethrough. Guidewire housing


213


slideably accommodates the guidewire


212


and allows the float


201


to slideably move along its float path between open positions and its closed position, FIG.


16


.




Attention is directed to FIG.


16


. In

FIG. 16

, it can be seen that sealing structure


209


has an outermost dimension which is greater than the outermost dimension of the valve seat


202


. If circular, the sealing structure


209


has a diameter which is greater than the diameter, if circular, of the valve seat


202


. This permits the valve assembly


200


to be closed to liquid flow therethrough.




In operation, during normal conditions when the air cleaner is above any level of liquid, the float


201


is held within the float support region


211


. Air is filtered through the air cleaner, as normal. As the vehicle and therefore the air cleaner move, the air cleaner may be subject to vibration. As the air cleaner vibrates or bounces, the float


201


is maintained within the float support region


211


and away from the valve seat


202


due to the non-linear extension


214


. If the vehicle is driven into deep liquid or water to a level which is above the inlet of the housing, the liquid reaches the outlet assembly housing


204


, and the float


201


floats on the surface of the water or liquid. As the liquid rises, the float


201


floats on the surface of the water and around the projection


215


. As the liquid rises and gets the float


201


close to the outlet


206


, air flow forces, drag, and/or vacuum facilitate the float


201


seating quickly in the valve seat


202


to block the outlet


206


. When float


201


blocks the air outlet


206


, the air intake to the engine is cut off, and the engine shuts down. The float


201


also prevents the liquid or water from being passed or sucked into the engine. The float


201


stays positioned on the valve seat


202


until the liquid level falls, even if the engine is turned off. As the liquid level falls, the liquid is allowed to drain through an aperture


220


in the outlet assembly housing


204


, and an aperture in the housing (for example, aperture


25


, FIG.


1


). As the liquid level falls, the float


201


falls from the valve seat


202


. This permits the engine to again be started, where air is allowed to flow through the air cleaner and out through the outlet tube


206


into the engine.




One Example Construction




In the following paragraphs, specific examples of a valve assembly are described. The valve assembly described is that as shown in

FIGS. 2-5

. It is understood, of course, that alternative constructions and dimensions may be utilized.




Outlet assembly


27


has a largest cross-sectional dimension at region where outlet assembly


27


joins filter element section


30


of about 7-7.25 inches (about 177.8-184.2 mm), for example, about 7.1 inches (about 180.3 mm). The width of outlet assembly


27


is about 3.8-4.2 inches (about 96.5-106.7 mm), for example, about 4 inches (about 101.6 mm). Outlet tube


48


of valve construction housing


42


has an inner diameter of about 2.3-2.5 inches (about 58.4-63.5 mm), for example, about 2.4 inches (about 61.0 mm). It has an outer diameter of about 2.6-2.9 inches (about 66-73.7 mm), for example, about 2.75 inches (about 69.9 mm). Housing construction


42


has a height between end


52


and end


53


of about 10-11 inches (about 254-279.4 mm), for example, about 10.6 inches (about 269.2 mm).




Wall member


54


extends between first end


52


and window region


56


about 3.5-3.7 inches (about 88.9-94.0 mm), for example, about 3.6 inches (about 91.4 mm). The inner diameter of float support region


50


is about 2.8-3 inches (about 71.1-76.2 mm), for example, about 2.9 inches (about 73.7 mm).




First ring


66


is located a distance of about 2.3-2.5 inches (about 58.4-63.5 mm), for example, about 2.4 inches (about 61.0 mm) from first end


52


. Second ring


67


is located a distance of about 3.4-3.6 inches (about 86.4-91.4 mm), for example, about 3.5 inches (about 88.9 mm) from first end


52


. Valve assembly


40


is used in an air cleaner housing


21


having a nominal size of about 5 in.×7 in., (about 127×177.8 mm) oval. It is used to filter air intake in engines having sizes typically of about 2-8 liter piston displacement and horsepower of about 100-300 (about 75 kw to 224 kw).




For example, the ratio of the float diameter to the valve seat inside diameter is at least 1.05. For example, a 2.5 in. diameter float would have a valve seat no larger than 2.38 in.




The above specification, examples and data provide a complete description of the manufacture and use of the invention. Many embodiments of the invention can be made without departing from the spirit and scope of the invention.



Claims
  • 1. A method for preventing liquid ingestion into an engine through an air intake, the method comprising steps of:(a) providing a valve assembly upstream of the engine; the valve assembly having a float and a valve seat; the float being movable along a float path between a first position away from the valve seat and a second position blocking the valve seat; and (b) inhibiting movement of the float along the float path to prevent movement of the float to the second position, unless a selected liquid volume within the valve assembly is attained.
  • 2. A method according to claim 1 wherein:(a) said step of inhibiting movement of the float along the float path includes having a projection arrangement in the valve assembly along the float path.
  • 3. A method according to claim 2 wherein:(a) said step of inhibiting movement of the float along the float path includes having a projection arrangement including a plurality of projection members extending into the float path.
  • 4. A method according to claim 3 wherein:(a) said step of inhibiting movement of the float along the float path includes having a plurality of projection members including first and second spaced rings positioned along the float path.
  • 5. A method according to claim 2 wherein:(a) said step of inhibiting movement of the float along the float path includes having a projection arrangement including a guide rod having a projection member along the float path.
  • 6. A method according to claim 1 wherein:(a) said step of inhibiting movement of the float along the float path includes having a cup constructed and arranged to retain the float within the cup by vacuum pressure.
  • 7. A method according to claim 1 wherein:(a) said step of inhibiting movement of the float along the float path includes having a non-linear guide rod to guide the float along the float path.
  • 8. A method according to claim 1 wherein:(a) said step of inhibiting movement of the float along the float path includes having a magnet in the valve assembly, and having the float be constructed of a material attracted to the magnet.
  • 9. A method according to claim 1 wherein:(a) said step of inhibiting movement of the float along the float path includes having a linkage attaching the float to the valve assembly.
Parent Case Info

This application is a Divisional of application Ser. No. 09/154,993, filed Sep. 17, 1998, now U.S. Pat. No. 6,009,898, which application(s) are incorporated herein by reference.

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