Title of Invention

"A CLOGGING INDICATING DEVICE FOR AN AIR FILTER ASSEMBLY FOR AUTOMOTIVE VEHICLES"

Abstract

The present invention relates to a clogging indicator for air filters used in automotive vehicles comprising a hollow casing capable of being covered by a cover and connected to the air filter assembly, said hollow casing having an open end for pulling in air into the filter assembly; a biasing means mounted within the hollow casing and extending therefrom, a sealing means with a downwardly extending piston cooperating with said biasing means, the dimensions of the piston and the cylindrical spring means being such that the piston is capable of seating itself on the top of such biasing means and exert compressive pressure thereon.

Full Text

Field of the invention The present invention relates to a clogging indicating devicl for an air filter ashnbly. More particularly, the present invention relates to a clogging indicator for air filters used in automotive vehicles. Background of the invention All automotive engines use an enriched mixture of air and fuel for combustion- in fact, this enriched mixture of air and fuel is essential for the functioning of all internal combustion engines. Air in internal fuel engines plays a dual role of lubricant as well as a combustion initiator due to the presence of oxygen therein. The air component in such enriched mixtures is generally drawn from the atmosphere and is injected with the fuel as fine spray to ensure speedy combustion. The air filter assembly is an integral and essential component of all such engines for automotive vehicles. Air filter assemblies in the art comprise primarily of a filter element intended to eliminate or reduce substantially the amount of particulate matter in air that is drawn into the engine such that the rate of combustion is maintained and engine damage, carburetor clogging etc. are prevented. The air filter element generally comprises a cylindrical device (other shapes are also possible) provided with multiple serrations on the external surface thereof and with a filter means normally comprising filter paper or any other conventional filtering fibers coated, mounted or laminated onto the internal surface thereof. The air intake is fed onto the air filter external surface of the filter element. Larger sized particulate matter is blocked by the serrated external surface of the filter element and gets deposited thereon and smaller size particulate matter that may permeate the external surface is absorbed onto the filter means provided on the internal surface of the filter element. The relatively pure air is driven into the engine through an output means provided at the lower end of the filter casing. The elimination of the particulate matter from the air intake contributes to the fuel efficiency as well as the life of the engine. Generally, in the art, air filters are replaced periodically depending on the life span indicated by the manufacturers. This periodic replacement does not bear any relevance to the actual amount of clogging that has occurred in the air filter. The disadvantage of this is that periodic replacement depends on the manufacturer -stipulated life span is fixed in spite of the fact that that the level of suspended particulate matter in the atmosphere varies geographically. Even in the same geographical location, the amount of suspended particulate matter such as dust particles can vary depending on whether the area where the automotive vehicle used is agricultural (more dust) or industrial (other particulate matter) or residential (less dust or other particulate matter). The life span indicated by air filter manufacturers does not hold true across different areas. As a result, often, in areas where there is a heavy particulate presence in the atmosphere such as rural agricultural areas, or industrial areas, the air filter gets clogged much before the end of the stipulated life span thereof. However, failure to replace the air filter on clogging could result in a initial pressure drop in the engine thereby resulting in reduced fuel efficiency, increased wear and tear in the engine and parts thereof, including engine failure and in extreme cases, even seizure. It is therefore, desirable for a vehicle user to be alerted in advance of the level of clogging so as to eliminate the possibility of wear and tear, engine failure or seizure and permit speedy and timely replacement of the air filter.. Objects of the invention It is therefore, an object of the invention to provide a clogging indicator for use in an automotive vehicle that enables regular and appropriate maintenance of the air filter assembly by indicating the clogging level therein. It is another object of the invention to provide a clogging indicator for use in conjunction with the air filter assembly of an internal combustion engine in automotive vehicles which by indicating the level of clogging in the air filter enables speedy and timely replacement of the air filter. It is a further object of the invention to provide a clogging indicator for use with air filter assemblies for automotive vehicles that reduces the wear and tear of engine. These and other objects of the invention are achieved by the clogging indicator of the present invention which enables timely replacement of air filters elements in automotive vehicles without requiring maintenance or check ups or disruption in usage of the vehicle. Summary of the invention The invention in its simplest form comprises a hollow casing capable of being covered by a cover means. The hollow casing covered by said cover means is connected to the air filters assembly. The hollow casing has an open end for pulling in air into the filter assembly. Mounted within the hollow casing and extending therefrom is a biasing means, which in a preferred embodiment is in the form of a cylindrical spring. A sealing means, which preferably comprises of a gasket with a downwardly extending piston cooperates with said cylindrical spring. The dimensions of the piston and the cylindrical spring means are such that the piston means is capable of seating itself on the top of such spring means and exert compressive pressure thereon. The piston may be integral with said gasket. In another embodiment, the piston and the gasket means may be two separate components, snugly mateable with each other. The cover means comprises of a deflecting disc fitted therein. Extending from said cover means and connected to said hollow disc is a second biasing means, preferably in the form of a coning spring. The hollow cover means is provided with two electrical terminals separated from each other and connected to an alarm device such as electric bulb, LED, sonar cell, buzzer, or the like. The clogging indicator assembly also includes a pair of electrical connectors. The electrical connectors are preferably metal or other conductive terminals with a seat or a flange at the base thereof. The flange enables the two connectors to be seated in specially provided grooves in the cover when in the assembled state. One of said connectors is connected to one of said electrical terminals within said casing. The other of said connectors sits freely and is capable of being electrically connected to the other of said electrical terminals when the disc means within said cover means is pulled upward. Both the connectors are connected to a suitable power source. In a normal state, said free or floating connector has no electrical contact with the second terminal within said cover means as a result of which the electrical circuit remains open. In an assembled state, the cover means fits neatly over the casing means. Both the casing means and the cover means may be equipped with flat annular shoulders which enable the cover means to sit upon the said casing means in an air tight fashion. In this state, the first spring means is partially compressed with the gasket snugly mating with the top of the piston. The two connectors are seated in the grooves and are enclosed completely by said cover means. The second spring means is flush against the top of the gasket and is in a compressed state with the disc deep within said hollow cover means away from the gasket. One of said connectors is connected on the upper part thereof to a terminal within said hollow cover, preferably on said disc. The upper portion of the second connector is preferably in a groove within said cover means and has no electrical contact with the second terminal. In normal course, the air is sucked through the air filter assembly, without any impediment. However, when the air filter starts getting clogged, there is a resistance for air suction through the air filter. In such a situation, air tends to be sucked through the open end of the hollow casing. The suction force created thereby establishes a vacuum inside the clogging indicator assembly which exerts a downward pull on said gasket. As a consequence, the gasket along with the piston pushes the first spring means causing it to compress further. This enables the second spring means to expand upward pulling up therewith, said disc means which then makes an electrical contact with said second connector means. The moment the disc means establishes contact with the second connector means, the electrical circuit is completed, immediately triggering the alarm indicating that the air filter is clogged and due for cleaning or replacement. The present invention provides a novel and efficient device for indicating the clogging level of the air filter, the very aspect of clogging rendering the device operational and triggering an alarm. Accordingly the present invention provides a clogging indicating device for an air filter assembly for antomotive velicles, comprising: a housing having a casing moans and a cover operatively associated therewith; said casing being connectable at one end thereof to the air filter assembly in an internal combustion engine, said casing .means being adapted to be responsive to the level of clogging in the air filter assembly; an air intake meangbeing provided on said casing to provide an initial restriction on air intake therethrough when the air filter clogging level is zero or low, a seal means operatively associated with said air intake means by means of a first spring means to cause a downward movement in said first spring means on air intake through the air intake means; said first spring means connected at one end on the internal surface of the end of said casing ,the other end of said first spring means being free and projecting out of the said opposite end of the said casing means, said first spring means being responsive to the intake of air through the said air intake means and moving downwards due to suction through the air intake means on intake of air when the air filter element is clogged; the said cover operatively associated with said casing to enclose therewithin said seal means and first spring means, a second spring means, extending from within said cover a switching means comprising of a moveable electecal terminal within said cover and at least a pair of connecton seated in scaid cover, at least one or both said connectors being free from electrical contact with said moveable terminal, an alarm device located external to said cover opposite the air filter assembly and operatively connected to said switching means, a power source connected to said switching means to form an open circuit when the clogging indicating device is non-operational and a closed circuit when said clogging device is operational, said alarm device being activated upon a complete circuit being established by the downward movement of the cover towards said air filter on the intake of air through said air intake means which causes said electric al terminal to establish contact with said connector or connectors. In one embodiment of the invention, said first spring means comprises a cylindrical spring open at both ends thereof, and connected at one end thereof to said casing means and at the other end thereof to a piston. In another embodiment of the invention the said seal means comprises of a piston and gasket assembly, said gasket being connected at one end thereof to said piston, said gasket pushing said first spring means also towards the casing means thereby pushing said piston towards the casing means on the intake of air through the air intake means. In another embodiment of the invention, said second spring means comprises a conical spring connected at the wider end thereof to said cover means and free at the narrow end thereof, said second spring means being movable in a direction towards said air filter assembly on the intake of air through the air intake means. In another embodiment of the invention, the switching means comprises at least two connectors, at least one of said connectors being connected to said cover means by means of a disc. In a further embodiment of the invention, the said other connector is free at the one end, the circuit being completed by the movement of the disc element located within said cover means towards the air filter assembly on the intake of air through the said air intake means. In another embodiment of the invention, the alarm device comprises any of conventional alarm means such as a visual display means, such as a graded meter, LEDs, light bulb, a sonar cell and the like. In another embodiment of the invention, said power source comprises the automotive battery of said internal combustion engine. In a further embodiment of the invention, said power source is an independent power source connected to said clogging indicating device and integral thereto. Brief description of the accompanying drawings Figure 1 is an exploded view of the clogging indicating device according to one embodiment of the invention showing all the components thereof and their respective connections and interconnections. Figure 2 is a section through the clogging indicating device of the present invention in an assembled state. Detailed description of the invention The present invention will now be explained in detail with reference to the accompanying drawings. It must however be understood that the accompanying drawings are merely illustrative and are not intended to limit the invention. Variations of the embodiments depicted are possible without departing from the scope and spirit of the invention. Referring now to Figures 1 and 2 where like numerals refer to like parts, the clogging indicating device of the invention comprises a two-part housing means (1) comprising of a casing means (2) and a cover means (3) operatively associated therewith. The casing means and the cover means are not integral with each other. The housing on the side of the casing means (2) is assembled at one end thereof to the air filter assembly (1) and responds to the level of clogging in the air filter element in said air filter assembly. The casing means (2) is provided at one end thereof with an air intake means (10) opposite to the air filter assembly (1). The air intake means (10) restricts the air intake through the clogging indicating device (1) when the air filter clogging level is zero or low. However, when the ail filter element is substantially clogged leading to reduced air intake through the air filter assembly, the air intake means (10) enables the intake of air through suction into the air filter assembly such that the clogging of the filter element of the air filter assembly is indicated. The air intake means (10) is operatively associated with a seal means (11) by means of a first spring means (12). When the air filter element of the air filter assembly is clogged substantially, the air intake means (10) causes the intake of air to the inlet of the engine. This results in the creation of a suction force acting in the same direction as the air flow. As a result of this suction, the seal means (11) is impelled towards the air filter assembly. The first spring means (12) is connected at one end thereof on the internal surface of the end of said casing means (2) assembled to said air filter assembly (1'). The other end of first spring means (12) is free and projects out of the opposite end of the casing means. The fseal means (11) is responsive to the intake of air through the said air intake means (10) and moves downwards due to suction through the air intake means (10) on intake of air when the air filter element is clogged. The cover means (3) is operatively associated with said casing means (2), enclosing therewithin said seal means (11) and first spring means (12). A second spring means (13), extends from said cover means (3). The clogging indicator includes a switching means comprising at least a pair of connectors (14, 15) and a disc (16). In the assembled state, the first spring means (12) is partially compressed with the seal means (11) just seated on the top of said partially compressed first spring means (11). The seal means consists of a gasket (18) connected to or integral with a piston (19). The two connectors (14) and (15), in the embodiment shown, have a vertical electrical terminal (20) and (21) respectively. The base of the connectors (14) and (15) may preferably be in the form of flanges or seats to enable said connectors to sit in the grooves in the cover (3). One of said connectors (15) is connected to said disc (16) making an electrical contact while other is free or floating or located within a groove inside the cover (3). Both the connectors are connected to a source of power (not shown). When the air filter element is clogged, the supply of filtered air to the engine through the air filter assembly reduces resulting in the creation of a high suction pressure at the inlet of the engine. As a result, air intake is initiated through the air intake means (10) on the clogging indicator (1). The intake of air through the air intake means (10) results in the creation of suction pressure and therefore, vacuum within the housing causing the seal means (11) to be puled downward. Thus, the pre-compressed second spring means (13) expands pulling down said disc and causing it to deflect, thereby bringing it into contact with the other connector (14). An alarm device is located external to said cover means (3) and connected to electric terminals provided within said cover (3). When a complete circuit is established as explained above, the clogging indicator means or an alarm device is activated signalling the clogging alert. Referring now to Figure 2, the casing means (2) is generally made of aluminium pressure die casting component and has a conical opening (21) at one end thereof and a threaded tapping (22) at the other end thereof. The casing means is connected to the air filter assembly by means of a hexagonal nut and an elbow. The casing means (2) contains the air intake means (10), the seal means (11) and first spring means (12). The air intake means is preferably made of sintered bronze filter element and also serves to initially restrict the flow of air into the engine inlet when the air filter element is substantially clean. The first spring means (12) preferably comprises a cylindrical spring connected at one end on the internal surface of the casing means (2) and at the other end is operatively associated with the seal means (11). The first spring means is preferably a cylindrical spring made of spring steel and remains compressed during normal functioning thereby ensuring that the switching means provided on the cover means is not activated. However, when the air filter element is clogged, the first spring means is further compressed, thereby allowing the second spring means (13) to push the switch means down to complete the circuit and activate the indicator means. The said seal means preferably, comprises a piston and gasket assembly with the gasket being connected at one end thereof to the piston. The gasket pushes the first spring means towards the casing means thereby also pushing the piston towards the casing means on the intake of air through the air intake means. The piston comprises a polyacetal piston and is integral with the first spring means. The first spring means is depressed on the intake of air through the air intake means. The gasket is provided on the seat of the case means and is preferably made of silicon rubber. A restriction of air intake by the air intake means is maintained above the gasket towards the cover means during the normal functioning of the air filter assembly. However, when the air filter element in the air filter assembly is clogged, an intake of air occurs through the air intake means resulting in the gasket bulging downwards towards the piston and first spring means, thereby pushing the first spring means downwards. This creates a space for the second spring means provided in the cover means to expand thereby dislodging the free connector element of the switch means from its groove to the disc thereby completing the circuit and activating the clogging indication means. The cover means of the invention houses the switching means, a second spring means (13) and is provided on the external upper surface thereof with leads to the clog indication means. The cover means is preferably made of any insulating material such as Bakelite. The first spring means (12) is generally cylindrical. The second spring means typically, comprises a conical spring connected at the wider end (71) thereof to the cover means (3) and free at the narrow end thereof (72). The second spring means is movable in a direction towards air filter assembly on the intake of air through the air intake means. The second spring means (13) is preferably a conical spring, made of spring steel of lower deflection rating than the first spring means (12). The second spring means remains compressed when the air filter element of the air filter assembly is free of clogging. However, on the air filter element becoming clogged, the second spring means expands to fill the vacant space created by the bulging of the gasket due to the creation of high suction pressure as a result of the intake of air through the air intake means. The switching means preferably comprises at least two connector elements (14,15) and a disc element (16). At least one of said connectors is permanently fixed to the disc element. The other connector is removably connected to the cover means (3) during the normal operation. However, on clogging of the air filter element in the air filter assembly, the downward pressure exerted by the movement of the gasket results in the second spring means expanding in the downward direction thereby deflecting the other connector from its position and bringing it into contact with the other connector element. This completes the circuit and activates the clog indication means. As described above, the first connector is preferably integral with the disc element provided on the cover means and is connected with the respective input lead of said power source to complete the circuit. In a variation of the switching means, the other connector element is also permanently fixed in the seat of the cover (3) but electrically insulated from the first connector element. The first connector is permanently fixed at the other end thereof to the input lead from the power source. On the downward expansion of the second spring, the disc (16) is deflected downwards to come into contact with the respective other lead of the power source through the other connector thereby completing the circuit and activating the clog indication means. The clogging indication means comprises any of conventional alerting means such as a visual display means, an audio alert means or a combination thereof. The power source may comprises the automotive battery of said internal combustion engine or be an independent power source connected to the clogging indicating device and integral thereto. During the normal functioning of the air filter, the air intake into the engine inlet is routed directly through the outlet of the air filter assembly. The first and the second spring means are both in compressed position thereby ensuring that the clog indication means remains deactivated since the circuit is not completed. In prior art filter assemblies when the air filter element is clogged, the amount of air intake available to the engine is reduced drastically causing in wear and tear of the engine and its spare parts as a result of the build up of pressure across the engine. In the instant invention the creation of high suction pressure at the engine inlet due to clogging of the air filter element of the air filter assembly results in activation of the air intake element of the clogging indicating device. The intake of air through the air intake device results in the creation of a suction pressure above the surface of the gasket, which in turn bulges downwards, compressing further the first spring means and expanding the second spring means. The expansion of the second spring means results in the circuit being completed since the two connector elements are in contact with the disc element and the power source. The clog indicating means is activated as a result of the completion of the circuit. It must be understood that the embodiments described above are exemplary and not intended to limit the invention. Variations of the embodiments depicted are possible without departing from the scope and spirit of the invention. We Claim : 1. A clogging indicating device for an air filter assembly for automotive vehicles, comprising: a housing having a casing and a cover operatively associated therewith; said casing being connectable at one end thereof to the air filter assembly in an internal combustion engine, said casing being adapted to be responsive to the level of clogging in the air filter assembly; an air intake means being provided on said casing to provide an initial restriction on air intake therethrough when the air filter clogging level is zero or low; a seal means operatively associated with said air intake means by means of a first spring means to cause a downward movement in said first spring means on air intake through the air intake means; said first spring means connected at one end on the internal surface of the end of said casing, the other end of said first spring means being free and projecting out of the said opposite end of the said casing, said first spring means being responsive to the intake of air through the said air intake means and moving downwards due to suction through the air intake means on intake of air when the air filter element is clogged; the said cover operatively associated with said casing to enclose therewithin said seal means and first spring means, a second spring means, extending from within said cover; a switching means comprising of a moveable electrical terminal within said cover and at least a pair of connectors seated in said cover, at least one or both said connectors being free from electrical contact with said moveable terminal, an alarm device located external to said cover opposite the air filter assembly and operatively connected to said switching means, a power source connected to said switching means to form an open circuit when the clogging indicating device is non-operational and a closed circuit when said clogging device is operational, said alarm device being activated upon a complete circuit being established by the downward movement of the cover towards said air filter on the intake of air through said air intake means which causes said electric al erminal to establish contact with said connector or connectors. 2 A clogging indicating device as claimed in claim 1 wherein said seal means comprises of a piston and gasket assembly, said gasket being connected at one end thereof to said piston, said gasket pushing said first spring means also towards the casing thereby pushing said piston towards the casing on the intake of air through the air intake means. 3. A clogging indicating device as claimed in claim 1 or 2 wherein said first spring means is a cylindrical spring open at both ends thereof, and connected at one end thereof to said casing and at the other end thereof to said piston. 4. A clogging indicating device as claimed in claim 1 wherein said second spring means is a conical spring connected at the wider end thereof to said cover and free at the narrow end thereof, said second spring means being movable in a direction towards said air filter assembly on the intake of air through the air intake means. 5. A clogging indicating device as claimed in any preceding claim wherein said switching means comprises at least two connector elements and one disc element, at least one of said connector elements being fixed to said disc element, said other connector element being removably connected to the cover and insulated from the said disc element and the first connector element when the switch is in the off position. 6. A clogging indicating device as claimed in claim 5 wherein the said other connector is integral with said disc provided on said cover such that on intake of air through said air intake means, the disc is deflected to establish contact with said other connector to complete the circuit. 7. A clogging indicating device as claimed in any preceding claim wherein the clogging indication is a visual display means, an audio alert means or a combination thereof. 8. A clogging indicating device as claimed in any preceding claim wherein said power source is the automotive battery of said internal combustion engine. 9. A clogging indicating device as claimed in claims 1 to 7 wherein said power source is an independent power source connected to said clogging indicating device and integral thereto. 10. A clogging indicating device for an air filter assembly for automotive vehicles substantially as herein described with reference to and as illustrated in the accompanying drawings.

Documents:

816-del-2001-abstract.pdf

816-del-2001-claims.pdf

816-DEL-2001-Correspondence-Others (11-02-2010).pdf

816-del-2001-correspondence-others.pdf

816-del-2001-correspondence-po.pdf

816-del-2001-description (complete).pdf

816-del-2001-drawings.pdf

816-DEL-2001-Form-1-(11-02-2010).pdf

816-del-2001-form-1.pdf

816-DEL-2001-Form-15-(21-12-2009).pdf

816-del-2001-form-19.pdf

816-DEL-2001-Form-2-(11-02-2010).pdf

816-del-2001-form-2.pdf

816-DEL-2001-Form-26-(11-02-2010).pdf

816-del-2001-form-3.pdf

816-del-2001-form-4.pdf

816-del-2001-gpa.pdf