Patent Publication Number: US-2009235824-A1

Title: Filtering Device To Filter The Air Taken In By A Cleaning Apparatus

Description:
FIELD OF THE INVENTION 
     The present invention concerns a filtering device to filter the air taken in by a cleaning apparatus by means of filtering elements, for example of the liquid bath type, or dry. To be more exact, the filtering elements are disposed in relative containing compartments, communicating with each other, and allow to retain the dirt, for example present in the air taken in, so as to separate the dirt from the air. 
     BACKGROUND OF THE INVENTION 
     Filtering devices are known, for example of the liquid  15  bath type, normally water, which are used in cleaning apparatuses, such as vacuum cleaners, or the so-called vacuum cleaners for liquid. 
     A filtering device is known comprising a container which defines a containing compartment containing the water, and which is provided with an inlet pipe for the air to be filtered and a discharge pipe for the filtered air. Intake members are provided, which generate an intake flow from the inlet pipe to the discharge pipe in order to put droplets of nebulized water into suspension, with which the dirt mixes. 
     The discharge pipe is provided with filters, for example of the spongy type, able to block the droplets of water. 
     However, this known filtering device has the disadvantage that it has a relatively low filtering capacity. 
     A filtering device is also known, whose container is provided with two containing compartments disposed one above the other and communicating with each other. 
     In this known solution, the intake members generate an intake flow from the inlet pipe to the discharge pipe through the two containing compartments in order to effect a progressive double filtering, thus obtaining a relatively high filtering capacity. However, the known double filtering device, although it offers a greater filtering capacity compared with known devices with a single containing compartment, is very complex and bulky. 
     In fact, the known double filtering device occupies a 10 relatively large space, especially in relation to the size of the cleaning apparatus in which it is normally used. 
     A purpose of the present invention is therefore to achieve a filtering device which is compact, which has a limited bulk with respect to known devices and which has a high filtering capacity. 
     The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages. 
     SUMMARY OF THE INVENTION 
     The present invention is set forth and characterized in the main claim, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea. 
     A filtering device according to the present invention is able to be used to filter the air taken in by a cleaning apparatus, such as for example a vacuum cleaner, a vacuum cleaner for liquids, or similar apparatus. 
     In accordance with the above purpose, the device  30  according to the present invention comprises a container, provided with a plurality of walls which define at least a first containing compartment, able to contain a first filtering element, and a second containing compartment, able to contain a second filtering element. Advantageously, at least one of the two filtering elements is of the liquid bath type, or dry. 
     According to a variant of the invention, at least one of 5 the two filtering elements comprises a gas, for example air. 
     The air to be filtered is able to be introduced into the first containing compartment through an inlet pipe. 
     In the second containing compartment, connected to the 10 first containing compartment by means of an intermediate pipe, the filtered air is able to exit through a discharge pipe. 
     According to a characteristic of the present invention, the two containing compartments are disposed one inside the other, and the innermost compartment is at least partly surrounded by the filtering element contained in the outermost compartment. 
     The filtering device according to the present invention allows to perform a progressive double filtering in a single container, therefore guaranteeing a high filtering capacity, while it is compact and has a limited bulk compared with known devices. 
     Advantageously, the filtering capacity of the device according to the present invention can be selectively varied, for example according to the material to be taken in, which can be dry, liquid or other, by varying the type of filtering element contained in each compartment. 
     According to one embodiment of the present invention, the two containing compartments are substantially co-planar with each other and, for example, substantially co-axial with each other. 
     The walls comprise an inner wall, an intermediate wall common to both the containing compartments, and an outer wall. 
     To be more exact, the inner wall and the intermediate wall define the innermost compartment, while the intermediate wall and the outer wall define the outermost compartment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein: 
         FIG. 1  is a three-dimensional view, partly sectioned, of a filtering device according to the present invention; 
         FIG. 2  is a section of the filtering device from II to 15 II of  FIG. 1 ; 
         FIG. 3  is a section of the filtering device from III to III in  FIG. 1 ; 
         FIG. 4  is a section of the filtering device from IV to IV in  FIG. 1 ; 
         FIG. 5  is a section of the filtering device from V to V in  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT 
     With reference to  FIG. 1 , a filtering device  10  according to the present invention can be used to filter, in a liquid bath, the air taken in by a cleaning apparatus. 
     The filtering device  10  comprises a container  12 , provided with a lower part  14 , which functions as a base, and an upper part  16 , which functions as a lid. 
     The container  12  ( FIGS. 1 to 5 ) comprises an outer wall  30   18 , an intermediate wall  20  and an inner wall  22 , walls which have a substantially arched shape, and are substantially parallel and coaxial with each other with respect to an axis X ( FIGS. 2 ,  3  and  4 ). 
     The inner wall  22  and the intermediate wall  20  define a first containing compartment  24 , having a partly annular shape. 
     The intermediate wall  20  and the outer wall  18  define a 5 second containing compartment  26 , outside with respect to the first compartment  24  and disposed adjacent and coaxial with the first containing compartment  24  with respect to the axis X. 
     The two containing compartments  24  and  26  are therefore  10  separated from each other by the intermediate wall  20  and are substantially co-planar to each other, that is, the two containing compartments  24  and  26  extend coaxially starting from a common bottom surface  50  of the container  12  ( FIGS. 4 and 5 ). 
     The device  10  also comprises an inlet chamber  28 , which is made above the first containing compartment  24 , and on one wall of which ( FIGS. 2 and 4 ) an inlet hole  30  is made for the air to be filtered. 
     The inlet chamber  28  also communicates with an inlet pipe  20   32 , which has a substantially tubular shape and has one lower end partly immersed in the water contained in the first containing compartment  24 . 
     Between the first containing compartment  24  and the second containing compartment  26  the device  10  comprises a transit chamber  34 , which is made above the two containing compartments  24  and  26 . 
     The transit chamber  34  communicates on one side with the first containing compartment  24  through a first aperture  36 , made above the level of the water, and on the other side with the upper end of an intermediate pipe  38 . 
     The intermediate pipe  38  is substantially tubular and has one lower end partly immersed in the water contained in the second containing compartment  26 . Between the second containing compartment  26  and the discharge pipe  18 , the device  10  also comprises a discharge chamber  40 , which is made above the first containing compartment  24  and is separated therefrom. 
     The discharge chamber  40  communicates on one side with the second containing compartment  26  through a second aperture  42 , made above the level of the water, and on the other side with the upper end of a discharge pipe  44 . 
     Downstream of the second containing compartment  26  an  10  intake unit is provided, of a substantially known type and not shown here, connected to the lower end  44   a  ( FIGS. 2 ,  3  and  4 ) of the discharge pipe  44 . 
     The intake unit generates an intake flow from the inlet pipe  32  to the discharge pipe  44 . 
     We shall now describe the functioning of the filtering device  10  according to the present invention. 
     The air, which is taken from the inlet hole  30 , passes through the inlet chamber  28  and the inlet pipe  32 , to mix with the water present in the first containing compartment  24 , so that the dirt contained therein is deposited on the bottom of the first compartment  24 . 
     After passing through the first containing compartment  26 , the air transits through the first aperture  36 , to pass into the transit chamber  34 . From here, the air passes inside the intermediate pipe  38  to mix with the water of the second containing compartment  26 . 
     In the second compartment  26  the dirt, still present in the already partly filtered air, is deposited in the water contained therein, while the completely clean air passes through the second containing compartment  26  and transits through the second aperture  42  to pass into the discharge chamber  40 . From here, the filtered air is introduced into the discharge pipe  44 , where filters are disposed, for example of the spongy type, able to block the water. 
     It is clear that modifications and/or additions of parts may be made to the filtering device  10  as described heretofore, without departing from the field and scope of the present invention. 
     It is also clear that, although the present invention has been described with reference to specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of filtering device for filtering the air taken in by a cleaning apparatus, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.