Abstract:
A pump inlet fitting for a wet/dry vacuum cleaner is disclosed. The pump inlet fitting frictionally attaches a pump inlet assembly to an inner surface of an intake tube of a wet/dry vacuum cleaner. The pump inlet fitting includes a plurality of radially extending barbs which frictionally engage the inner surface of the intake tube to a degree sufficient to secure the pump inlet assembly to the intake tube without the need for costly and time consuming external clamping mechanisms.

Description:
FIELD OF THE INVENTION 
     The invention generally relates to wet/dry vacuum cleaners, and more particulary relates to inlet fittings for wet/dry vacuum cleaners which include pumping capability. 
     BACKGROUND OF THE INVENTION 
     Wet/dry vacuum cleaners are well known. Such devices typically include a large reservoir or tank having a bottom and an annular side wall to which a lid is attached to enclose the tank. A motor-driven impeller and other mechanics associated with creation of a vacuum are typically mounted within the lid with a flexible hose being mountable to an inlet to the vacuum. Debris, including solids, liquids, and gases, are drawn in by the vacuum and deposited into the tank. When the tank is full, the lid needs to be removed to dump the debris gathered within the tank. However, the weight of the tank and collected debris can be substantial, often preventing lifting of the tank or even tilting of the tank to empty its contents. 
     Recently, wet/dry vacuum cleaners have been provided which also include a pumping capability. Therefore, in addition to being able to draw matter into the tank, such devices include a mechanism by which the fluid within the tank can be expelled under power without the need of removing the lid to the tank and lifting or tilting the tank. Examples of such devices are disclosed in U.S. Pat. No. 6,009,596, assigned to the present assignee and expressly incorporated herein by reference. Other examples are disclosed in pending U.S. patent application Ser. Nos. 09/513,607, and 09/589,492, both of which are assigned to the present assignee and expressly incorporated herein by reference. 
     In wet/dry vacuum cleaners having a pump located within a lid of the device, an intake tube typically extends downwardly from the pump into the tank. A pump inlet assembly is typically attached to the base of the intake tube to provide a mechanism by which the pump can be primed, as well as a mechanism through which the fluid being pumped can be filtered. With typical prior art designs, the filter intake assembly is secured to the end of the intake tube using conventional band clamps. The pump inlet assembly is secured around the outer surface of the intake tube with the band clamp then being secured around the outer surface of the pump inlet assembly. While effective, such a design has proven to be less than ideal for assembly and reliability purposes. 
     SUMMARY OF INVENTION 
     In accordance with one aspect of the invention, a wet/dry vacuum cleaner pump inlet assembly is provided which is adapted to be mounted to an inlet tube within a tank of a wet/dry vacuum cleaner. The pump inlet assembly includes an inlet housing and an inlet fitting. The inlet housing includes the top plate and an annular wall extending from the top plate. The top plate also includes an opening for receipt of the inlet tube. The inlet fitting includes a bottom plate and a mounting leg extending from the bottom plate. The bottom plate is frictionally secured to the inlet housing annular wall, and the mounting leg is frictionally secured to an inner surface of the inlet tube. 
     In accordance with another aspect of the invention, a wet/dry vacuum cleaner pump inlet fitting is provided for a wet/dry vacuum cleaner having a pump adapted to expel liquid from a tank of the vacuum cleaner. The pump inlet fitting comprises a base, a leg extending from the base, and a plurality of barbs radially extending from the leg. The barbs are adapted to frictionally engage an inner surface of an intake tube of the pump in order to secure the fitting to the intake tube. 
     In accordance with another aspect of the invention, a wet/dry vacuum cleaner is provided which comprises a tank, a vacuum source mounted on the tank to draw fluid into the tank, a pump mounted on the tank to expel fluid from the tank, an intake tube extending from the pump into the tank, and an inlet assembly mounted on the intake tube. The inlet assembly includes a filter such that fluid to be expelled from the tank is drawn through the filter, into the inlet assembly, and through the intake tube. The inlet assembly is frictionally mounted to an inner surface of the intake tube. 
     These and other aspects and features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a wet/dry vacuum cleaner constructed in accordance with the teachings of the invention; 
     FIG. 2 is a sectional view of FIG. 1 taken general at along line  2 — 2  of FIG. 1; 
     FIG. 3 is an enlarged sectional view of the pump inlet assembly of FIG. 2; 
     FIG. 4 is an exploded view of the pump inlet assembly constructed in accordance with the teachings of the invention; 
     FIG. 5 is a top view of a pump inlet fitting constructed in accordance with the teachings of the invention; and 
     FIG. 6 is a cut-away sectional view of the pump inlet fitting and mold used in constructing the pump inlet fitting. 
    
    
     While the invention is susceptible to various modifications and alternative instructions, certain illustrative embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative instructions and equivalents falling within the spirit and scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, and with specific reference to FIG. 1, a wet/dry vacuum cleaner constructed in accordance with the teachings of the invention is generally depicted by reference numeral  20 . While the invention is described and illustrated in conjunction with the wet/dry vacuum cleaner  20 , is to be understood that the teachings of the invention can be employed with other types of vacuum cleaners, as well as other types of pumps, wherein quick attachment of inlet fittings is desirable. 
     As shown in FIG. 1, the vacuum cleaner  20  includes a base  22  to which a lid  24  is attached. The base  22  may include a plurality of casters  26  to facilitate movement of the vacuum cleaner  20 . The lid  24  may include a pair of handles  28  to facilitate removal of the lid  24 , as well as lifting of the vacuum cleaner  20 . 
     Referring now to FIG. 2, a power assembly  30  is shown mounted in the lid  24 . The power assembly  30  includes a motor  32  connected by a shaft  34  to a vacuum impeller  36 , as well as a pump impeller  38 . As described in pending applications of the present assignee, the vacuum cleaner  20  can be operated to take advantage of either the vacuum impeller  36  or only the pump impeller  38 . The present invention is directed to operation in a pumping mode. 
     The pump impeller  38  is mounted for rotation within a pump housing  40  which includes an inlet  42 . An intake tube  44  extends from the inlet  42  downwardly into a reservoir or tank space  46  defined by the base  22 . The intake tube  44  includes an upper end  48  which is preferably dimensioned to frictionally mount to a stub  50  associated with the inlet  42  to facilitate easy attachment when operating the vacuum cleaner  20  in a pump mode. 
     The intake tube  44  also includes a lower end  52  to which a pump inlet assembly  54  is attached. As will be described in further detail herein, the pump inlet assembly  54  is adapted to frictionally mount to an inner surface  56  of the intake tube  44 . 
     Referring now to FIGS. 3 and 4, the pump inlet assembly  54  is shown in detail. The pump inlet assembly  54  includes an inlet housing  58 , as well as an inlet fitting  60 . The inlet housing  58  and inlet fitting  60 , when mounted together, cooperate to form inlet space  62  in fluid communication with the intake tube  44  and thus the pump housing  40 . 
     The inlet housing  58  includes a top plate  64  having a central aperture  66  and an annular wall  68 . The annular wall  68  is formed from multiple portions  70  (see FIG.  4 ), or is otherwise imperforate, to allow for fluid communication therethrough. A mounting lip  71  downwardly extends from the top plate  64  proximate the central aperture  66 . The annular wall  68  is slightly less in diameter than the diameter of the top plate  64  such that an annular flange  72  is formed. 
     With reference now to FIGS. 3-5, the pump inlet fitting  60  is shown to include a bottom plate or base  74  from which a mounting leg  76  upwardly extends. As shown best in FIG. 5, the mounting leg  76  preferably includes four walls  78  which extend radially outwardly and are spaced approximately ninety degrees apart. The bottom plate  74  includes a circumferential recess  80  radially inward of a flange  82 . As shown best in FIG. 3, the annular wall  68  of the inlet housing  58  is frictionally received within the recess  80  to connect the inlet housing  58  to the inlet fitting  60 . Fasteners  83  (FIG. 4) may be used to further secure the inlet housing  58  to the inlet fitting  60 . Additionally shown in FIG. 3, the flange  82  of the inlet fitting  60  cooperates with the flange  72  of the inlet housing  58  to secure a filter element or medium  84  (FIG. 2) therebetween. The filter element  84  is preferably annular in shape to surround the annular wall  68  and is manufactured from a suitable material to screen large particles from fluid passing from the tank  46  into the inlet space  62 . 
     As shown in FIGS. 3-5, certain of the walls  78  include barbs  86  to facilitate frictional interference between the mounting leg  76  and the inner surface  56  of the intake tube  44 . The barbs  86  are formed at a juncture between a canted surface  88  and a shoulder  90 . The canted surface  88  tapers radially outwardly from a reduced diameter end  92  of the mounting leg  76  to the shoulder  90 . The shoulder  90  extends radially outwardly from a reduced diameter recess  94  to the canted surface  88 . 
     In the preferred embodiment, three of the four walls  78  are provided with barbs  86 . The fourth wall  78 ′ (see FIG. 6) includes an angled top surface  96  and a uniform diameter side surface  98 , with no barb  86  being provided. 
     In operation, it will be appreciated that the invention provides a quick and straightforward mechanism by which the inlet assembly  54  can be secured to the intake tube  44 . As a result, the time and labor involved in assembling the inlet assembly  54  is greatly reduced. More specifically, the intake tube  44  is secured to the stub  50 , and the inlet assembly  54  is secured to the lower end  52  of the intake tube  44  simply by inserting the mounting leg  76  of the inlet fitting  60  into the intake tube  44 . The canted surfaces  88  of the wall  78  facilitate sliding insertion action and centering of the mounting leg  76  within the intake tube  44 . Once the mounting leg  76  is inserted into the intake tube  44  to a degree sufficient to allow the shoulder  90  to pass the lower end  52 , the barbs  86  frictionally grip the inner surface  56  of the intake tube  44 . The frictional interference between the barbs  86  and the inner surface  56  sufficiently secure the pump inlet assembly  54  to the intake tube  44  to negate the need for external fastening mechanisms, including metal band clamps, employed by prior art devices. When inserted, the four walls  78  cooperate with the intake tube  44  to define four intake quadrants  99  through which fluid may pass. 
     Referring now to FIG. 6, a portion of a mold  100  used for manufacturing the inlet fitting  60  is partially depicted. The inlet fitting  60 , as well as the inlet housing  58  is preferably manufactured from injection molded plastic. In order to manufacture the barbs  86  in the walls  78 , the mold  100  includes an outer member  102 , as well as a moveable jiggle pin  104 . A separate base mold member would be employed to form the bottom plate or base  74 , and is not depicted in FIG.  6 . However, once the bottom mold member is removed, the inlet fitting  60  can be pulled away from the outer mold member  102  with the jiggle pin  104  moving with the inlet fitting  60  in the direction indicated by an arrow  106 . Once the jiggle pin  104  is moved sufficiently away from the mold member  102 , the barbs  86  are freed from frictional interference with a jog  108  formed in the jiggle pin  104 , thus freeing the inlet fitting  60  from the mold  100 . In order to allow for removal of the inlet fitting  60  from the mold  100 , not all of the walls  78  include the barbs  86 , with only three of the four walls  78  including such barbs  86  in the depicted embodiment. 
     From the foregoing, one of ordinary skill in the art will appreciate that the invention provides a pump inlet housing and pump inlet fitting which easily and quickly enables an operator to attach a pump inlet assembly to a pump intake tube.