Patent Description:
For many applications there is a need for a filtration device that enables the filtering of liquids. Even though the filtration device disclosed below is suitable for many different applications, the invention is described using the example of a water filter without limiting the invention to a water filtration device.

Usually, such filtration devices comprise a container body with a storage area for collecting and holding the liquid, e.g. water, until there is a need for extracting a quantity of the liquid from the filtration device. The container body comprises an inlet which allows for filling the liquid into the storage area within the container body. The inlet can be closed liquid-tight with a lid in order to prevent any unwanted contamination of the liquid inside the storage area from the outside. The container body further comprises an outlet which allows for removal of the liquid after the filtration process.

A suitable filter element is arranged in the flow path between the inlet and the outlet of the container body. For some filtration devices the filter element is located inside of the storage area and connected to the inlet or outlet of the filtration device. Some other filtration devices comprise a filter element that is located outside of the storage area and connected with the storage area by means of a conduit. The filter element may be arranged between the inlet and the storage device or between the storage device and the outlet.

Many different filter elements are known in prior art, comprising different types of filter media usually disposed in the flow path through the filter element. The filter media may comprise activated carbon, zinc or copper, or similar materials that improve e.g. the quality of drinking water. The filter element may also comprise membranes or porous materials that remove particles with a particles size that is larger than the pore size of the membrane or porous material that is arranged within the flow path.

For some filtration devices, the container body is a bottle with an opening that is used for filling water into the bottle as well as for extracting filtered water from the bottle. The opening is usually closed with a cap, whereby a filtering element is mounted at the cap and covers a spout in the cap, through which the filtered water can be extracted from the bottle. Such bottles can easily be carried by a user and used when needed. Sometimes, the cap comprises a spout or an outlet at which a user can suck filtered water from the bottle.

In order to facilitate the extraction of filtered water from the bottle, some bottles comprise an air pump that in many cases is also mounted to the cap. By manually or automatically operating the air pump a pressure increase inside of the bottle can be generated, resulting in a flow of a corresponding amount of water from the inside of the bottle through the filter element and through the spout or outlet towards outside of the bottle. Such filtration devices are disclosed e.g. in <CIT> or in <CIT>. However, a cap that contains the inlet and outlet, and that contains or supports the filter element and the air pump is expensive to manufacture and difficult to clean.

Some other filtration devices comprise a container body that is intended for stationary use. The volume of the storage area inside such a container body may be adapted for personal or household use and allow for holding e.g. one or several liters. Such a filtration device is disclosed e.g. in <CIT>. A filter element is located at an outlet of a cube-shaped vessel. By applying pressure within the vessel, the liquid stored inside the vessel will be caused to flow through the filter element and pass out of the vessel via the outlet. The outlet may be located on top of the vessel, and the filter element can be mounted at the outlet. It is also possible to located the outlet of the vessel at the bottom, and to provide for an external conduit, namely a riser pipe, that extends upwards and leads to an outlet of the conduit above the top of the vessel. The filter element can be a part of this conduit or can be inserted into this conduit, allowing for positioning the filter element outside of the vessel. However, repeated cleaning of the vessel after intervals of use is laborious, as not all areas of the vessel are easily accessible.

A filtration device with a cylindrical-shaped or oval-shaped storage area that is easily accessible via a large opening at the top of the container body is disclosed in <CIT>. For some of the disclosed embodiments, a conduit is an integral part of the filter element and is used or exchanged together with the filter element. It is also described to make use of a conduit that is designed like a riser pipe and attached to the container body. The riser pipe leads from an opening at the bottom of the container body towards a spout located above the fill line of the storage area inside the container body. As with the filtration device discussed above, handling and cleaning of such a filtration device is laborious.

Thus, there is a need for a filtration device which facilitates handling and cleaning. The objective of the present invention was to provide for a filtration device, which can be easily cleaned without need for manually cleaning angled areas or areas that are difficult to access.

<CIT> discloses a personal water purification system providing a watertight polymeric container having a removable, threaded inlet fill cap that provides access to an unfiltered upper water receiving chamber. At the lowest integral portion of the receiving chamber, a threaded port is provided for the attachment of a disposable filter cartridge that is vertically threaded into the port. This allows for gravity-induced filtering as opposed to pressure-induced filtering. A plurality of filtered water ports are also located in the lower integral portion of the unfiltered water chamber, one or more opposite the other and/or juxtaposed, which allow filtered water to be dispensed through a plurality of channels/conducts from a lower filtered water chamber to a drinking spout provided at a topmost portion of the container, and to flow by gravity when the container is tipped to its side.

<CIT> discloses a pressurised water bottle that includes a pressurising tube that delivers air into the bottle to pressurise. Unfiltered water placed in the bottle from a removable top is delivered through a tube that pushes the pressurised water through the bottle and through a filter and out through a spout and to the user to ultimately ingest.

<CIT> discloses a water treatment unit positioned adjacent a bottom of a sports water bottle. An elongate opening at a top of the water treatment unit is connected to an opening in a cap of the bottle by an elongate conduit such as a straw. The bottle is preferably formed of a flexible material, such as plastic, so that when the bottle is squeezed water will be forced from an interior of the bottle surrounding the unit through an inlet, the water treatment unit, the straw and the opening.

The present invention relates to a filtration device as defined in claim <NUM>. As all liquid-contacting parts except of the filter element, namely the storage area, the riser pipe and the outlet are manufactured as a one-piece container body, there is no need to dismantle these parts before cleaning. Furthermore, there are no joints where impurities or deposits from the liquid can accumulate and stick, which then have to be cleaned with considerable effort. The design and shape of the one-piece container body may be adapted to allow for easy access of all areas inside of the one-piece container body which further facilitates the cleaning of all parts of the filtration device that will be in contact with the liquid during the intended use of the filtration device. According to an advantageous aspect of the invention, the inlet of the container body is arranged above the filling level of the storage area and has a cross-sectional area which corresponds to the cross-sectional area of the storage area, so that the storage area is accessible without undercuts via the inlet. A large opening of the container body provides for easy access of the inside of the container body.

In accordance with an embodiment of the invention, the seating for the filter element is only accessible from the storage area. The seating for the filter element may be located at the bottom of the storage area. The seating is preferably designed and arranged in a manner as to allow for an easy mounting of the filter element in a position that fully covers the output opening of the storage area. Thus, the flow path of liquid that is extracted from the storage area must traverse the filter element before entering the extraction conduit with the riser pipe. The cross-section of the storage area is preferably large enough to allow for a person to mount or dismount the filter element inside the storage area by hand and without the need for tools.

In yet an alternative embodiment that is also considered advantageous, the seating for the filter element is accessible from outside of the container body via a filter opening in the container body, whereby the filter opening is sealed liquid-tight with a removable filter opening lid, allowing the mounting or removal of the filter element through the filter opening. The filter opening is preferably located close by the seating, allowing easy access to the seating from the outside of the container body, which facilitates the mounting and dismounting of the filter element in the seating. The filter opening can also be arranged close to the output opening of the storage area and thus close to the input end of the riser pipe, which facilitates access to this end of the riser pipe for cleaning purposes.

The filter element may have a screw thread so that the filter element can be screwed into the seating. It is also possible to engage the filter element with the seating using a bayonet lock or a snap-in connection. In its position inserted into the seating, the filter element can be sealed against the seating with an additional sealing element.

In order to reduce the handling effort required to replace a used-up filter element, it is optionally possible that the filter element is mounted to the filter opening lid. The filter opening lid may also be an integral part of a one-piece housing of the filter media of the filter element. The seating of the filter element can be used simultaneously as seating for the filter opening lid. An exchange and replacement of the filter element only requires the dismounting of the filter opening lid from outside of the container body, the removal of the filter element together with the filter opening lid, and subsequent remounting a new filter element until the filter opening lid closes the filter opening in a liquid-tight manner. The design of the seating may be adapted for e.g. a bayonet lock or a screw cap. The combined filter element and filter opening lid may comprise sealing components like e.g. sealing rings which simultaneously serve to seal the filter opening of the container body as well as the filter element against the seating and thus the flow path of the liquid through the filter element.

In accordance with a particularly advantageous embodiment of the invention, the output end of the riser pipe is connected via a duct to the laterally spaced outlet, whereby the duct is a gutter that is open at the top. Thus, the riser pipe as well as the duct and the laterally spaced outlet are open at the top, allowing for easy access to all volumes and areas inside of the one-piece container body. If the container body is placed upside down on the top of the container body, any liquid that is previously inside the container body will completely flow out of the container body. Thus, if the container body is cleaned by using a cleaning liquid like, e.g. water with cleaning agents followed by clean water, after placing the container body upside down all remaining water will flow out of the container body and there is no need for manually drying or wiping out the inside of the container body.

The top side of the open duct can optionally be covered by a duct cover that can be fixed on the duct and retained in that position by frictional force or positive locking of the duct cover. The duct cover prevents any unwanted contamination by particles or dust of the riser pipe that runs into the duct. The duct cover can be made of some elastomeric synthetic material that allows the clipping on of the duct cover on top of the duct. Alternatively, the duct cover can be made e.g. of a rigid plastic material or of stainless steel, which allows for a snap-in connection on top of the open duct. It is also possible to combine the duct cover with a lid that covers the inlet of the container body that is next to the duct. By making the duct cover an integral part of a one-piece top lid that covers simultaneously the inlet of the storage area of the container body as well as the open duct, the number of different parts that must be disassembled for cleaning the filter device and that must be reassembled after a cleaning process can be reduced. The duct cover that is removably attachable to the top of the duct combines protection of the filtered liquid against contamination and unwanted exposure to dust etc. with considerable facilitation of cleaning the duct.

According to another aspect of the invention the outlet comprises a downward pointing spout. A downward pointing spout facilitates the targeted removal of the filtered liquid. In addition, an aerator or a swiveling nozzle, for example, can be attached to the downward-facing spout to make it as convenient as possible to remove the filtered liquid. It is also possible that a further mechanical filter, for example a filter membrane, can be detachably attached to the downward pointing spout.

In order to further facilitate the cleaning of the filtration device, the container body may optionally be made of a dishwasher suitable material, preferably a dishwasher safe material. Thus, the container body can be put into a dishwasher for cleaning the container body. By placing the container body upside down without any lids and duct cover inside a dishwasher, the dishwasher can perform a full cleaning of the container body, usually without need for any additional manual cleaning or further manual processing as e.g. drying or wiping of regions inside of the container body that are difficult to access. Furthermore, the one-piece container body does not require any disassembling of parts before putting the container body inside a dishwasher. In addition, no interstices or joints are required for the container body that might allow for unwanted accumulation and retention of contamination, which might require additional manual handling and cleaning procedures.

According to an advantageous aspect of the invention the filtration device comprises a base part to accommodate the container body, whereby the pressure generating device is arranged inside of the base part and pressure-transmitting connected to the storage area if the container body is accommodated on the base part. The pressure generating device might comprise an electrically operated air pump with a connecting air tube that leads into the storage area inside the container body. The air pump, the required electrical parts and the energy supply can be arranged inside the base part. The electrical energy can be provided by batteries or via an electrically conductive connection to the household energy supply. It is also possible to provide for a manually operated air pump that can be arranged within the base part. In yet another embodiment, it is also possible to arrange the air pump inside a lid that covers the storage area of the container body. Thus, there is no need for a connecting air tube that connects the air pump with the storage area inside the container body.

In case that the filtration device comprises such a connecting air tube, it may be advantageous that the pressure generating device is separated by a check valve from the storage area inside the container body. The check valve can be arranged either inside the container body or as part of the base part or of the connecting air tube. The check valve may have a valve ball which is lifted from the valve seat by the overpressure generated by the air pump and releases the air tube as long as the overpressure is maintained.

The present invention will be more fully understood, and further features will become apparent, when reference is made to the following detailed description and the accompanying drawings. The drawings are merely representative and are not intended to limit the scope of the claims. In fact, those of ordinary skill in the art may appreciate upon reading the following specification and viewing the present drawings that various modifications and variations can be made thereto without deviating from the innovative concepts of the invention. Like parts depicted in the drawings are referred to by the same reference numerals.

By way of example, <FIG> illustrates a filtration device <NUM> according to an embodiment of invention. The filtration device <NUM> comprises a container body <NUM> with a storage area <NUM> for holding a liquid <NUM> to be filtered by the filtration device <NUM>. The container body <NUM> comprises an inlet <NUM> for filling the liquid into the storage area <NUM> within the container body <NUM>. The inlet <NUM> is a large opening on top of the container body <NUM>, whereby the inlet <NUM> has a cross-sectional area that corresponds to the cross-sectional area of the storage area <NUM>. Thus, the storage area <NUM> is accessible from the top side of the container body <NUM> via the inlet <NUM> without any undercuts or edges, which facilitates access to the storage area <NUM> inside the container body <NUM>.

A lid <NUM> can be removably attached over the inlet <NUM> to the container body <NUM>. The lid <NUM> can be mounted pressure-tight onto the container body <NUM>. The lid <NUM> may comprise a pressure generating device <NUM> that is only hinted at in <FIG>. The pressure generating device <NUM> can be operated manually or automatically, e.g. by an electric pump. By operating the pressure generating device <NUM>, air is pumped into the storage area <NUM> via an air tube <NUM> with a check valve <NUM>.

A filter element <NUM> is located in a seating <NUM> with a thread at a bottom <NUM> of the storage area <NUM> inside the container body <NUM>. The filter element <NUM> could also be mounted into the seating <NUM> by a bayonet lock or by a snap-in connection. An extraction conduit <NUM> connects the storage area <NUM> via the filter element <NUM> through a riser pipe <NUM> with an outlet <NUM> for discharging the liquid <NUM> from the storage area <NUM> inside the container body <NUM>. The riser pipe <NUM> is arranged along an outside wall <NUM> of the storage area <NUM> of the container body <NUM>. The riser pipe <NUM> extends from the bottom <NUM> of the storage area <NUM> to the outlet <NUM> close to the top of the container body <NUM> next to the inlet <NUM> with the lid <NUM>. An input end <NUM> of the riser pipe <NUM> is next to the filter element <NUM>. An output end <NUM> of the riser pipe <NUM> is connected via a horizontal duct <NUM> with the outlet <NUM> with a downward pointing spout <NUM>.

The duct <NUM> is designed as a gutter that is open at the top. The gutter leads to the outlet <NUM> that is also open at the top. A duct cover <NUM> can be mounted on top of the duct <NUM> in order to protect the open gutter from any unwanted contamination e.g. by particles or dust that may fall into the gutter. The duct cover <NUM> is made of an elastomeric synthetic material that allows for releasably mounting the duct cover <NUM> onto the duct <NUM> by clipping on, plugging on or pushing the duct cover <NUM> onto the duct <NUM>. It is also possible to make use of a duct cover <NUM> that is made of a rigid plastic material or of a suitable metal, e.g. a sheet material or stainless steel.

The storage area <NUM>, the seating <NUM> for the filter element <NUM>, the extraction conduit <NUM> comprising the riser pipe <NUM> and the outlet <NUM> are integral parts of the one-piece container body <NUM>. Thus, with the exception of the replaceable filter element <NUM>, all components that are in contact with the liquid <NUM> are manufactured one-piece and without the need for any joints or gaps between individual parts, which must be manufactured separately and then assembled to form the filtration device <NUM>.

After removal of the lid <NUM>, the storage area <NUM> of the container body <NUM> can be filled with the liquid <NUM> to be filtered by the filtration device <NUM>. After filling the storage area <NUM> with the liquid <NUM>, the lid <NUM> can be mounted pressure-tight on top of the container body <NUM>. Afterwards, if the pressure generating device <NUM> is operated, either manually or by means of an electric pump, the pressure inside the storage area <NUM> rises and a corresponding portion of the liquid <NUM> is forced through the filter element <NUM> that is arranged at the bottom <NUM> of the storage area <NUM>, resulting in performing a filtration process and providing a portion of filtered liquid <NUM> that is discharged through the extraction conduit and the outlet <NUM> from the container body <NUM>. By operating the pressure generating device <NUM>, the filtered liquid <NUM> rises through the riser pipe <NUM> and then flows through the horizontally running duct <NUM> and out of the downward directed outlet spout <NUM> of the outlet <NUM>.

In order to perform a cleaning of the filtration device <NUM>, the lid <NUM> can be removed from the container body <NUM> and the duct cover <NUM> can be removed from the duct <NUM>. Afterwards, the filter element <NUM> is easily accessible from the inlet <NUM> and can be manually removed from the seating <NUM> by performing a rotational movement of the filter element <NUM>, causing the filter element <NUM> to rotate out of the seating <NUM>. After removing the filter element <NUM> from the bottom <NUM> of the storage area <NUM>, the remaining one-piece container body <NUM> can be easily cleaned e.g. by placing the container body <NUM> upside down into a dishwasher. All areas inside of the container body <NUM>, including the riser pipe <NUM> and the duct <NUM>, are easily accessible from the top side of the container body <NUM>.

<FIG> illustrates another embodiment of the container body <NUM>, whereby only a lower region of the container body <NUM> is shown. The filter element <NUM> is mounted into a seating <NUM> that is accessible via a filter opening <NUM> at a bottom <NUM> of the container body <NUM>. Before filling the liquid <NUM> into the storage area <NUM>, the filter opening <NUM> can be closed liquid-tight with a filter opening lid <NUM> that can be screwed into a thread <NUM> on the edge of the filter opening <NUM>. The filter element <NUM> is attached on top of the filter opening lid <NUM>. By mounting the filter opening lid <NUM> into the filter opening <NUM>, the filter element <NUM> is located within the seating <NUM> for the filter element <NUM> at the bottom <NUM> of the storage area <NUM>. A gap between the filter element <NUM> and the seating <NUM> is sealed liquid-tight by an O-ring gasket <NUM>, which is arranged in a circumferential groove around the circular-shaped filter element <NUM>. Instead of arranging a O-ring gasket <NUM> within the gap, it is also possible to make use of other suitable sealing elements like e.g. an elastomeric sealing lip. A flow-through filter medium <NUM> or, in case of a combined filter element <NUM>, several filter media <NUM> are arranged between the storage area <NUM> and the extraction conduit <NUM>, forcing any liquid that is discharged from the storage area <NUM> through the extraction conduit <NUM> towards the outlet <NUM> to flow through the filter medium <NUM>.

Thus, the filter element <NUM> is easily accessible from outside of the container body <NUM>. A spent filter element <NUM> can be replaced by removing the filter opening lid <NUM> from the bottom <NUM> of the container body <NUM> and by inserting a new filter element <NUM> together with a corresponding filter opening lid <NUM> into the filter opening <NUM> at the bottom <NUM> of the container body <NUM>.

Claim 1:
A filtration device (<NUM>) for liquids, comprising a container body (<NUM>) with a storage area (<NUM>) for holding the liquid (<NUM>) to be filtered by the filtration device (<NUM>), whereby the container body (<NUM>) comprises an inlet (<NUM>) for filling the liquid (<NUM>) into the storage area (<NUM>) within the container body (<NUM>) and with an outlet (<NUM>) that is connected to the storage area (<NUM>) via an extraction conduit (<NUM>) for extracting the liquid (<NUM>) from the storage area (<NUM>) through the extraction conduit (<NUM>) and out of the outlet (<NUM>), whereby the extraction conduit (<NUM>) comprises a riser pipe (<NUM>) with an output end (<NUM>) located above a maximum filling level of the liquid (<NUM>) within the storage area (<NUM>) and connected to the outlet (<NUM>), whereby the filtration device (<NUM>) further comprises a filter element (<NUM>) that is arranged inside the container body (<NUM>) such that the liquid (<NUM>) that is extracted from the container body (<NUM>) must pass the filter element (<NUM>) before flowing out of the outlet (<NUM>),
wherein the container body (<NUM>) comprises a seating (<NUM>) for removably mounting the filter element (<NUM>) to the container body (<NUM>), and
wherein the storage area (<NUM>), the riser pipe (<NUM>) and the outlet (<NUM>) are integral parts of the one-piece container body (<NUM>), characterised in that
an input end (<NUM>) of the riser pipe (<NUM>) is connected to an output opening of the storage area (<NUM>) located at a bottom part of the container body (<NUM>), and in that
the filtration device further comprises a pressure generating device (<NUM>) for generating pressure within the container body (<NUM>) causing the liquid (<NUM>) to pass out of the container body (<NUM>) by flowing from the storage area (<NUM>) through the extraction conduit (<NUM>) and out of the outlet (<NUM>).