Abstract:
An aquarium filter system comprising a pump, a manually positionable valve assembly, and one or a plurality of interchangeable filter cartridges. The filter cartridges are interchangeable and replaceable without the need to suspend water flow. The filter cartridges may be readily repositioned relative to their location from the pump. In method form, a method of changing filter cartridges in an aquarium filter is disclosed. The method comprises supplying a pump and pumping water to provide a continuous flow of water from the aquarium to one or a plurality of removable filter cartridges. This is followed by isolating any one or plurality of the filter cartridges from the flow of water and replacing any one or plurality of filter cartridges with one or a plurality of unused filter cartridges. This is all accomplished under conditions such that the continuous flow of water is uninterrupted.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates generally to an aquarium filter system, and more particularly to a filter system having one or more replaceable filter cartridges which can be replaced without turning the system off. The cartridges individually and independently provide biological, chemical and/or particulate filter of the aquarium environment. The system includes a valve assembly capable of by-passing any of the filter cartridges to simplify removal and replacement.  
         BACKGROUND OF THE INVENTION  
         [0002]    Filters have been used in aquariums for many years to remove particulate matter from the aquarium water in order to keep the aquarium clean. Traditionally, the most common type of aquarium filter is a power filter which hangs on the outside of the aquarium over the top edge thereof. It includes a siphon tube which carries water from the aquarium into a filter box. Water entering the filter box flows over various types of filter media to remove particulate matter from the water. The water passes through filter carbon to remove chemical impurities from the water which is then pumped back into the aquarium using a filter pump. Examples of such power filters include the Supreme Aqua King power filter marketed by E. G. Danner Manufacturing Co.; the Second Nature Whisper power filter marketed by Willinger Bros. Mfg. Co.; and the Aqua Clear power filter marketed by Rolf Hagen Manufacturing Co.  
           [0003]    Another type of aquarium filter is a canister type filter which may be positioned outside and below the aquarium. Intake and output hoses hang over the aquarium edge and are connected to the canister filter on the floor. Water is fed by gravity through the intake hose from the aquarium to the canister. The aquarium water is both mechanically and chemically treated and pumped back into the aquarium by a pump contained in the canister. Examples of canister type filters include the Hagen Fluval filter marketed by Hagen USA Mfg., Co., Marine Land Canister Filter marketed by Aquaria, Inc., and Eheim Classic Canister Filters, marketed by Eheim GmbH &amp;Co. KG.  
           [0004]    An internally mounted power filter is still another type of aquarium filter. Such a filter comprises a small canister with a built-in pump which is submerged inside the aquarium. Water enters the bottom of the canister and flows through a filter sleeve which removes particulate and chemical waste. The filtered water is then pumped out the top of the canister and back into the aquarium. Examples of this type of filter are the Supreme Ovation internal filter marketed by Danner Mfg. and the Hagen Fluval internal filter sold by Hagen USA Mfg. Co.  
           [0005]    Still another type of filter employed in aquariums is the undergravel filter which consists of a perforated raised plate which rests on the aquarium floor. Riser tubes are provided on either end of the filter and extend into the top of the aquarium. Gravel is placed on top of the plate to a thickness of about  2 ″. Air lines from an external pump are placed in the riser tubes to the bottom plate and an air stone is placed at the end of the air lines. Air is forced by the pump through the air stones thereby forcing air bubbles to travel up through the tubes to the water surface creating turbulence or current. Water is then pulled through the gravel and forced up the riser tubes. Waste from the aquarium is drawn through the gravel bed where bacteria break down any ammonia or nitrites to less harmful nitrates. A biological filter does not, however, remove chemical wastes. Examples of such undergravel filters include filters marketed by Perfecto Mfg. and Penplex Mfg.  
           [0006]    Yet another type of prior art filter commonly used in aquariums is a wet/dry trickle type filter which includes a skimmer box that hangs inside the aquarium at the top. Siphon tubes are provided for carrying water from the aquarium to a prefilter which is mounted directly behind the skimmer box on the outside of the aquarium. Water passes through foam sleeves in a pre-filter to trap particulate matter. The water then travels through the hose in a tank typically positioned beneath the aquarium. As water enters the tank beneath the aquarium, it flows onto a drip plate or spray bar in a dry chamber of filters which contains a plurality of plastic biospheres. Water drips over and through the biospheres to the bottom section of the tank. Bacteria colonies grow on all biospheres which feed on waste products in the water passing over them. From there, the water gathers in the bottom of the filter tank and then passes through a carbon filter or other filter to remove chemical wastes from the water. The water is then passed through dolomite, crushed coral or crushed clam shells to buffer the water which is then pumped through the return hose back to the aquarium. Wet/dry filters can include mechanical, chemical and biological filters. Examples of such filters are the Plus Series trickle filter marketed by Oceanic System, Inc. and the Perfecto Wet/Dry filtration system sold by Perfecto Mfg. Co.  
           [0007]    Wet/dry filters may also be built into the aquarium and form a permanent part of the tank. One such wet/dry filter that is permanently built into the tank is marketed by Tenecor Corporation of Tempe, Ariz.  
           [0008]    An alternative form of the wet/dry filter is an internally mounted wet/dry filter which includes an integrated pump and heater for small aquariums. The filter is placed inside the aquarium against the rear wall with the top of the filter at the water level. Water enters the filter and then passes through the filter cartridge which removes particulate and chemical waste materials. A portion of the water is then pumped into a drip plate in a dry chamber for biological filtration. The remaining water is then pumped directly back into the aquarium so as to bypass the dry area. One such filter is marketed by Rolf Hagen Mfg. under the trademark “Biolife” filter.  
           [0009]    As should be clear from the above, proper and continuous filtration is critical to keeping happy, healthy fish, and there are three basic filtration methods: mechanical, biological and chemical. However, one long-standing problem is, e.g., that while freshly charged filter media accomplish their intended goals, over time, they tend to loose efficiency.  
           [0010]    For example, mechanical filtration, the means by which large particles of excess food and other debris are removed, screened, or skimmed from the water, may become clogged over time, reducing their ability to function as intended. Chemical filtration uses activated carbon and ammonia absorbents, such as zeolite, to remove odor, colors and harmful substances, such as ammonia, from the water. However, activated carbon will also loose its effectiveness over time and will similarly need replacement.  
           [0011]    In addition, while replacement of mechanical and chemical filtration is ultimately necessary, careful attention must be placed upon the primary means of removing ammonia and nitrites (by-products of fish waste), which is the biological filter. A well-established aquarium is a natural ecosystem in which fish and the beneficial bacteria that naturally occur in an aquarium depend upon each other to live happily and healthy. The result of this interrelationship is commonly referred to as the “Nitrogen Cycle”. Fish eat and produce ammonia as a waste product. Excess food and plant materials also decay and produce ammonia. Beneficial bacteria neutralize the ammonia and produce nitrites, which in turn are neutralized by other beneficial bacteria that produce nitrates. Nitrates in normal levels are harmless to freshwater fish, and over time, can be readily removed from the aquarium by partial water changes. Thus the natural system in an aquarium converts toxic ammonia into harmless nitrates; all without chemicals or consumer assistance.  
           [0012]    Expanding upon the above, there clearly needs to be a place for the bacteria to foster and grow within the filter system. It turns out that bacteria will grow on any porous surface in the filter assembly, e.g., on the media in a canister filter that pumps a steady flow of water for the bacteria to survive. That is, the water must be oxygenated as the bacteria require oxygen to reproduce and grow. An aquarium with proper aeration of the water and good water flow over the beneficial bacteria will provide sufficient oxygen to maintain the beneficial bacteria. And, of course, there must be a source of food (ammonia) for the bacteria. Any tank with fish or plants will provide sufficient food. The filtration system then circulates the ammonia carrying water over the beneficial bacteria for them to eat.  
           [0013]    Once established, the bacteria inside, e.g., the canister filter assembly are clearly invaluable and critical for a successful aquarium. However, as noted, the need to remove and regularly exchange portions of the filter (chemical and mechanical media) is also necessary. However, when exchanging mechanical and chemical media, it is important to do so in a manner that would not totally disrupt the biological filter media, which could lead to catastrophic results.  
           [0014]    That being the case, aquarium filtration technology has not yet developed a filter assembly system that would allow the hobbyist a convenient way to exchange portions filter media without disrupting water flow. More specifically, aquarium filtration technology has not yet provided a canister filter assembly comprising one or a plurality of cartridges, that could each be conveniently removed and exchanged for new media while maintaining regular water flow and minimized impact on the biological filter bed.  
           [0015]    Accordingly, it is an object of this invention to provide a filter system that can be mounted to or near the aquarium that has one or more particulate, biological and/or chemical filter cartridges that can easily be replaced. It is also an object of the invention to provide a filter system that allows the user to replace any of the filter cartridges without having to shut the entire system down, and without repriming the system when completed, and without affecting other filter cartridge sections, and without getting wet in the process.  
         SUMMARY OF THE INVENTION  
         [0016]    In broad aspect, the present invention comprises an aquarium filter system comprising a pump, a manually positionable valve assembly, and one or a plurality of interchangeable filter cartridges, said filter cartridges interchangeable without the need to suspend water flow. The filter cartridges may be readily repositioned relative to their location from the pump.  
           [0017]    In method form, a method of changing filter cartridges in an aquarium filter is disclosed. The method comprises supplying a pump and pumping water to provide a continuous flow of water from said aquarium to one or a plurality of removable filter cartridges. This is followed by isolating any one or plurality of the filter cartridges from said flow of water and replacing said one or plurality of filter cartridges with one or a plurality of unused filter cartridges. This is accomplished under conditions such that the continuous flow of water is uninterrupted by the practice of isolating and replacing said one or plurality of filter cartridges with said one or plurality of unused filter cartridges.  
           [0018]    More particularly, the present invention comprises a device for directing the flow of water from an aquarium through or around a plurality of filters and back into the aquarium. The device comprises a first diverter moveable between a first and a second position, in the first position the flow of water from the aquarium enters a first filter and in the second position the flow of water from the aquarium by-passes the first filter. The device also includes a second diverter moveable between a first and a second position, in the first position, the flow of water from the aquarium enters a second filter and in the second position the flow of water from the aquarium by-passes the second filter, wherein the second diverter is moveable between the first position and the second position independent of the first diverter.  
           [0019]    The present invention also provides a device for directing the flow of water from an aquarium through or around a plurality of series coupled filters and back into the aquarium. The device comprises a first diverter moveable between a first and a second position, in the first position, the flow of water from the aquarium enters a first filter and in the second position the flow of water from the aquarium by-passes the first filter. The device includes a second diverter moveable between a first and a second position, in the first position, the flow of water from the aquarium enters a second filter and in the second position the flow of water from the aquarium by-passes the second filter. The device also includes a positionable actuator, the actuator coupled to the first and the second diverters, the actuator moveable between at least three positions, in the first position, the aquarium water is directed through the first filter and the second filter, in the second position, the aquarium water is directed around the first filter and through the second filter, and in the third position, the aquarium water is directed through the first filter and around the second filter. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]    The above and other objects and advantages of the present invention will become readily apparent by reference to the following description when considered in conjunction with the accompanying drawings, wherein:  
         [0021]    [0021]FIG. 1 is a schematic of an aquarium system consistent with the present invention.  
         [0022]    [0022]FIG. 2A is a sectional view of a first embodiment valve assembly consistent with the present invention.  
         [0023]    [0023]FIG. 2B is a sectional view of a second embodiment valve assembly consistent with the present invention.  
         [0024]    [0024]FIG. 3 is a top view of a first embodiment diverter consistent with the present invention.  
         [0025]    [0025]FIG. 4 is a side view of the diverter of FIG. 3 taken through line  4 - 4 .  
         [0026]    [0026]FIG. 4 a  is a side view of a second embodiment diverter consistent with the present invention.  
         [0027]    [0027]FIG. 5 is a side view of the diverter of FIG. 3 taken through line  5 - 5 .  
         [0028]    [0028]FIG. 6 is a top view of a second embodiment diverter consistent with the present invention.  
         [0029]    [0029]FIG. 7 is a table relating actuator position of the spindle in FIG. 6 and the corresponding filter function. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]    [0030]FIG. 1 shows a basic schematic of an aquarium filter system  100  in accordance with the present invention. Water to be filtered exits an aquarium through a pipe or conduit  102 . The water is urged into to the filter system by a pump  104 . The pump may be located before, after, or internal to a valve assembly  108 . The water to be filtered leaves the pump through a conduit  106  and enters the valve assembly  108 . The direction of the water may be controlled by a series of controllable diverters  110 ,  120 , and  130 . In the embodiment shown, the number of filter shown is three, the quantity of filter cartridges can be increased or decreased without departing from the invention. The filters may comprise a particulate, biological, and a chemical filter and may be positioned in any order. The first controllable diverter  110  can direct the water into a first filter  114  or around the filter. In a first position, the diverter directs the water through a conduit  112 A to the first filter  114  for filtering. The water exits the filter  114  through a conduit  116  that joins with a conduit  118 . In the second position, the diverter  110  directs the water through a by pass conduit  112 B, and not through the first filter  114 , which joins with conduit  118 . In the second position, the filter  114  can be removed without allowing a continuous stream of water to exit the valve assembly  108 . The water may be prevented from flowing backwards through the system by either using one-way or backflow valves  140 A-F or by proper design of the valve assembly as will be shown below.  
         [0031]    Water enters the second controllable diverter  120  through the conduit  118 . The second diverter  120  can direct the water into a second filter  124  or around the filter. In a first position, the diverter directs the water through a conduit  122 A to the second filter  124  for mechanical, chemical or biological filtering. The water exits the filter  124  through a conduit  126  that joins with a conduit  128 . In the second position, the diverter  120  directs the water through a bypass conduit  122 B, and not through the second filter  124 , which joins with conduit  128 . In the second position, the filter  124  can be removed without allowing a continuous stream of water to exit the valve assembly  108 .  
         [0032]    Water enters the third controllable diverter  130  through the conduit  128 . The third diverter  130  can direct the water into a third filter  134  or around the filter. In a first position, the diverter directs the water through a conduit  132 A to the third filter  134  for filtering. The water exits the filter  134  through a conduit  136  that joins with a conduit  138 . In the second position, the diverter  130  directs the water through a by pass conduit  132 B, and not through the third filter  134 , which joins with conduit  138 . In the second position, the filter  134  can be removed without allowing a continuous stream of water to exit the valve assembly  108 . The water returns to the aquarium through the conduit  138 . A heater for maintaining the water at a predetermined temperature is not shown. The heater can be installed in series with the valve assembly  108  or separately. The valve assembly  108  may be housed in a housing  108 A or  108 B.  
         [0033]    [0033]FIG. 2A shows a sectional view of a first embodiment valve assembly  200  coupled to a plurality of filter cartridges. The valve assembly and the cartridges can be coupled to a side of an aquarium or in close proximity. The valve assembly  200  may comprise a plurality of individually positionable diverters  110 A,  120 A, and  130 A. Gaskets, not shown, may be used around the diverters to prevent water leaks. A portion  152 A of the diverters may extend outside the valve assembly housing  108 A to allow a user to reposition the diverter between or among a plurality of positions. The diverters  110 A,  120 A, and  130 A are shown as rotatable disks that rotate about an axis  156 A. Alternatively, the diverters can be linearly positionable. The first diverter  110 A is shown in a “filtering” position. The incoming water is directed by the first diverter  110 A into the first filter  114  through the conduit  112 A. The conduit may be made of a rigid or flexible plastic. Alternatively, the first diverter  110 A can be positioned in a “bypass” position to allow the water to bypass the first filter  114 . Thus no water enters the filter  114 . After flowing through the first diverter  110 A, the water is directed to the second diverter  120 A. The second diverter  120 A is shown in the “bypass” position. The second diverter  120 A directs the incoming water through a bypass  122 B. Thus no water enters the filter  124 . Alternatively, the second diverter  120 A can be positioned in the “filtering” position to allow the water to enter the second filter  124  through the conduit  122 A. After flowing through the second diverter  120 A, the water is directed to the third diverter  130 A. The third diverter  130 A is shown in the “filtering” position. The incoming water is directed by the third diverter  130 A into the third filter  134  through the conduit  132 A. Alternatively, the diverter  130 A can be positioned in the “bypass” position to allow the water to bypass the third filter  134 . Thus no water enters the filter  134 .  
         [0034]    When any of the diverters are in the “bypass” position the corresponding filter can be removed from the filter system without a continuous stream of water exiting the filter system. The diverters may include a visual indicator  158 A to indicate to the user if the diverter is in the “filtering” position or the “bypass” position. Because the diverters  110 A,  120   a,  and  130 A can be positioned independent of each other, more than one filter can be replaced simultaneously.  
         [0035]    As can therefore be appreciated, any one of filters  114 ,  124  and/or  134  can be isolated from the filter assembly and replaced. In that regard, if, e.g., filter  114  served principally a mechanical filter, and filter  124  principally provided chemical filtration, and filter  134  contained filter media with maximum surface area for beneficial bacteria, filter  114  could be readily removed without adversely effecting the beneficial bacteria of filter  134 . In this manner, the hobbyist is now uniquely provided the opportunity to conveniently clean the filter system, in a manner that is not disruptive to the developed biological filter bed, since water flow need not be completely shut-down.  
         [0036]    [0036]FIG. 2B shows a sectional view of a second embodiment valve assembly  300 . The valve assembly  300  may comprise a plurality of coupled positionable diverters  110 B,  120 B, and  130 B housed within the valve assembly housing  108 B. The diverters  110 B,  120 B, and  130 B may be mechanically coupled through a spindle  160  and move in unison. A portion of the spindle  160  may extend out of the top of the housing  108 B and form an actuator  162  for allowing the user to reposition the spindle  160  between or among a plurality of positions. The diverters  110 B,  120 B, and  130 B are shown as rotatable disks that rotate about an axis  156 B. Alternatively, the diverters can be linearly positionable. The first diverter  110 B is shown in a “filtering” position. The incoming water is directed by the first diverter  110 B into the first filter  114 . Alternatively, the first diverter  110 B can be positioned in a “bypass” position, by rotation of the actuator  162 , to allow the water to bypass the first filter  114 . After flowing through the first diverter  110 B, the water is directed to the second diverter  120 B. The second diverter  120 B is shown in the “bypass” position. The second diverter  120 B directs the incoming water through a bypass  122 B. Alternatively, the second diverter  120 B can be positioned in the “filtering” position to allow the water to enter the second filter  124 . After flowing through the second diverter  120 B, the water is directed to the third diverter  130 B. The third diverter  130 B is shown in the “filtering” position. The incoming water is directed by the third diverter  130 B into the third filter  134 . Alternatively, the diverter  130 B can be positioned in the “bypass” position to allow the water to bypass the third filter  134 .  
         [0037]    When any of the diverters are in the “bypass” position the corresponding filter can be removed from the filter system without a continuous stream of water exiting the system. An indicator placed on the actuator  162  on the top surface of the housing  108 B can visually indicate to the user which filter, if any, can be removed without causing a loss of water from the system.  
         [0038]    [0038]FIG. 3 shows a top view of a first embodiment of a diverter  400  for use in the valve assembly  200  shown in FIG. 2A. The diverter  400  is shown as a disk  402  having a plurality of openings  404 A,  404 B and  406 C. Opening  404 A may start a spaced distance from the central axis of the disk and extend to the edge of the disk  402 . A similarly shaped opening  404 B may be located on an opposite surface of the disk. The openings  404 A and  404 B are shown along a top surface  408  and a bottom surface  410  of the disk  402 , but may alternatively be positioned a spaced distance below the surfaces as shown in FIG. 4A. Opening  406 C may be a through hole that extends from the top surface  408  to the bottom surface  410 . The openings  404 A and  406  are angularly offset by 45°. The openings can be offset by any angular offset without departing from the present invention. Depending on the size and angular displacement of the openings, the system can maintain the flow of water through the system without having to temporarily interrupt the flow of water as the actuator is repositioned.  
         [0039]    [0039]FIG. 4 is a side view of the diverter  400  of FIG. 3 taken through line  4 - 4 . Water entering the diverter  408  through the opening  404 A is direct radially outward towards a filter  114 ,  124 , or  134 . Water from the filter  114 ,  124 , or  134  reenters the diverter through the opening  404 B and is directed downwardly. When the diverter has the opening  404 A aligned with the inlet conduit  106 ,  118 ,  128 , the water to be cleaned is directed into the filter  114 ,  124 , or  134 . When the diverter has the opening  406 A aligned with the inlet conduit  106 ,  118 ,  128 , the water to be cleaned bypasses the filter  114 ,  124 , or  134 .  
         [0040]    [0040]FIG. 5 is a side view of the diverter  400  of FIG. 3 taken through line  5 - 5 . Water entering the diverter  408  through the opening  406 C passes through without entering the filter  114 ,  124 , or  134 .  
         [0041]    [0041]FIG. 6 shows a top view of a second embodiment of a diverter  500  for use in the valve assembly  300  shown in FIG. 2B. The diverter  500  is shown as a disk  502  having a plurality of openings  504 A- 504 E and  506 . Openings  504  may start a spaced distance from central axis of the disk and extend to the edge of the disk  502 . Similarly shaped openings  504 A′ through  504 E′ (not shown) may be located on an opposite surface of the disk. The openings  504 A- 504 E are shown along a top surface  508  and corresponding openings  504 A′- 504 E′ (not shown) are located along a bottom surface  410  the disk  502 , but may alternatively be positioned a spaced distance below the surface similar to FIG. 4A. Opening  506  may be a through hole that extends from the top surface  508  to the bottom surface  510 . The opening  504 A- 504 E and  506  are angularly offset by 45°. The openings can be offset by any angular offset without departing from the present invention. The diverter  500  may include a multi-sided opening  510  formed about the diverter axis.  
         [0042]    As shown in FIG. 2B, a plurality of diverters may be stacked to form a valve assembly  300 . The multi-sided spindle  160  may be inserted through the opening  510  to couple the diverters  110 B,  120 B, and  130 B. The diverter may or may not be spaced from each other as shown in FIG. 2B. The diverter  500  and housing  108 A and  108 B may be manufactured by injection molding. The same diverter  500  can be used in each of the three locations A, B, and C to form diverter  110 B,  120 B, and  130 B. The diverter  500  when located in location A can be coupled to the spindle  160  at a first angular position relative to the actuator  162 , the diverter  500  when located in location B can be coupled to the spindle at a second angular position relative to the actuator  162 , and the diverter  500  when located in location C can be coupled to the spindle at a third angular position relative to the actuator  162 .  
         [0043]    [0043]FIG. 7 is a table relating the angular position of the actuator  162  and the corresponding filter function. When the actuator  162  is positioned in the first angular position P 1 , all of the filters are connected in series. Opening  504 C is aligned with conduit  106 , which directs the water in to the first filter  114 , opening  504 B is aligned with conduit  118 , which directs the water in to the second filter  124 , and opening  504 A is aligned with conduit  128 , which directs the water in to the third filter  134 .  
         [0044]    When the actuator  162  is positioned in the second angular position P 2 , filter  114  is by passed and filters  124  and  134  are connected in series. Opening  506  is aligned with conduit  106 , which directs the water around the first filter  114 , opening  504 C is aligned with conduit  118 , which directs the water in to the second filter  124 , and opening  504 B is aligned with conduit  128 , which directs the water in to the third filter  134 .  
         [0045]    When the actuator  162  is positioned in the third angular position P 3 , filter  124  is by passed and filters  114  and  134  are connected in series. Opening  504 D is aligned with conduit  106 , which directs the water into the first filter  114 , opening  506  is aligned with conduit  118 , which directs the water around the second filter  124 , and opening  504 C is aligned with conduit  128 , which directs the water in to the third filter  134 .  
         [0046]    When the actuator  162  is positioned in the fourth angular position P 4 , filter  134  is by passed and filters  114  and  124  are connected in series. Opening  504 E is aligned with conduit  106 , which directs the water into the first filter  114 , opening  504 D is aligned with conduit  118 , which directs the water into the second filter  124 , and opening  506  is aligned with conduit  128 , which directs the water around the third filter  134 . More openings  504  and  506  may be added to the disk  502  to allow more than one filter to be replaced simultaneously.  
         [0047]    In addition, it should be noted that in the broad context of the present invention, it is preferable to provide a unique pathway for the flow of water in the filter, such that backpressure is minimized. For example, it is preferable to construct the filters disclosed herein with a spiral pathway, which increases the surface area for filtration efficiency and which also reduces backpressure, thereby affording additional and unique operating advantages.  
         [0048]    It should be understood that, while the present invention has been described in detail herein, the invention can be embodied otherwise without departing from the principles thereof, and such other embodiments are meant to come within the scope of the present invention as defined in the following claim(s)