Patent Abstract:
A latching mechanism for a dust cup assembly on a bottom exit cyclone-separator vacuum cleaner including a non-rotating sealing conduit member that supports a dust cup assembly above a discharge outlet coupled to a sliding latch member via pin-mounted linkages. The conduit member raises and lowers the dust cup assembly into and out of engagement with the cyclone separator coincident with horizontal sliding movement of the latch member in and out underneath the dust cup to releasably attach and detach the dust cup assembly from the cyclone separator.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 60/981,672, filed Oct. 22, 2007, and is a continuation-in-part of U.S. patent application Ser. No. 12/121,026, filed May 15, 2008, which claims the benefit of U.S. Provisional Patent Application No. 60/938,583, May 7, 2007, all of which are enclosed herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to vacuum cleaners. In one of its aspects, the invention relates to a vacuum cleaner with a dirt cup that is removably mounted to a cyclone separator. In another of its aspects, the invention relates to a vacuum cleaner with an improved latch for removably mounting a dirt cup to a cyclone separator. 
     2. Description of the Related Art 
     Upright vacuum cleaners that use cyclone action to separate dust, dirt, and contaminates entrained in the airflow are well known. U.S. Pat. No. 7,191,490 to Lee et al. discloses a top exit cyclone assembly including a soil collection receptacle at a lower portion thereof and having a sliding groove formed on the bottom surface that confronts the floor of an accommodation recess on the handle. A guide member is located at the lower end of the soil collection receptacle, wherein the guide member is formed with a pair of guide projections at opposite sides and an operation lever adapted to move the guide member up and down to raise and lower the soil collection receptacle in sealing relation to the cyclone assembly. The guide member moves up and down as the operation lever is pushed and pulled horizontally relative to the handle. 
     U.S. Pat. No. 6,732,406 to Oh shows a removable dust cup that slides out from under the cyclone chamber. The dust cup is locked in place and released by a rotating handle that directly engages a slanted, spiraling recess on the bottom of the dust cup. Rotating the handle in a first direction raises the dust cup toward the bottom of the cyclone chamber, locking the dust cup in place; rotating the handle the opposite direction lowers the dust cup from the cyclone chamber for emptying. 
     U.S. Pat. No. 6,735,816 to Oh et al. discloses a removable dust cup that is raised and lowered into and out of engagement with the cyclone chamber by a rotating lever. The rotating lever raises and lowers the dust cup through an intermediate, non-rotating locking disc operating against the bottom of the dust container. 
     U.S. Pat. No. 6,991,667 to Yang et al. discloses a dust cup supported on a coaxial filter case to provide a direct suction path between the motor below it and the cyclone chamber above it. The filter case provides an extra stage of filtration and dust separation for the air exiting the cyclone chamber through the dust cup into the motor housing. The filter case is securely fixed to an annular lever and seal member that surrounds and seals the airflow path from the filter to the motor housing; the dust cup is detachable from the filter case. The annular lever and seal member is mounted to rotate as a unit on a cam structure on the motor housing cover, raising the lever and seal assembly and filter case up and down, and thus raising and lowering the dust cup into and out of engagement with the cyclone chamber. 
     SUMMARY OF THE INVENTION 
     According to the invention, a vacuum cleaner comprises a housing with a cyclone separation chamber having an inlet opening and an outlet opening, a dust cup assembly removably mounted beneath the cyclone separation chamber and having a dust cup with an exhaust conduit extending through the dust cup between the cyclone separation outlet opening and a discharge opening in a bottom wall of the dust cup, and a latching mechanism positioned beneath the dust cup assembly for raising the dust cup into engagement with the cyclone separation chamber and for lowering the dust cup from engagement with the cyclone chamber. The latching mechanism comprises a sealing conduit member mounted in the housing beneath the dust cup assembly in fluid communication with the exhaust conduit when the dust cup is in engagement with the cyclone separation chamber and a sliding latch member coupled to the sealing conduit member via at least one linkage member and being movable relative to the housing to raise and lower the sealing conduit member into and out of engagement with the dust cup assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a front perspective view of an upright vacuum cleaner with a dust cup assembly and latching mechanism according to the invention. 
         FIG. 2  is an exploded front perspective view of the dust cup assembly and latching mechanism of the vacuum cleaner of  FIG. 1 . 
         FIG. 3  an exploded perspective view of the latching mechanism of  FIG. 2 . 
         FIG. 4A  is a partial front perspective view of the dust cup recess with the latching mechanism in a pre-installation position. 
         FIG. 4B  is a partial front perspective view of the dust cup recess with the latching mechanism in an installed position. 
         FIG. 5  is a sectional view taken along line  5 - 5  of  FIG. 1  of the latching mechanism in a latched position, in which the latch is engaged and raised. 
         FIG. 6  is a sectional view taken along line  6 - 6  of  FIG. 1  of the latching mechanism in an unlatched position, in which the latch disengaged and lowered. 
         FIG. 7  is a sectional view taken along line  7 - 7  of  FIG. 1  of the latching mechanism in a latched position, in which the latch is engaged and raised. 
         FIG. 8  is a sectional view taken along line  8 - 8  of  FIG. 1  of the latching mechanism in an unlatched position, in which the latch disengaged and lowered. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An upright vacuum cleaner  10  with an improved dust cup latching mechanism  38  according to the invention is shown in  FIG. 1 . A suitable vacuum cleaner is shown in more detail in International Application No. PCT/US2004/034841, filed Oct. 21, 2004, and U.S. patent application Ser. No. 12/121,026, filed May 15, 2008, both of which are incorporated herein by reference in their entirety. The vacuum cleaner comprises an upright handle assembly  12  pivotally mounted to a conventional foot assembly  14 . Referring to  FIGS. 1 and 2 , the upright handle assembly  12  comprises a handle grip  16 , a cyclone separation module  18 , a suction motor/fan assembly (not shown) positioned below the cyclone separation module  18  within a lower portion of the upright handle assembly  12  generally indicated by reference numeral  19 , and a dust cup recess  22  having a rear wall  23  joined to a bottom wall  25 . A suction motor/fan inlet conduit  24  extends through the bottom wall  25  and a pair of opposed receiving channels  26  to retain and guide the improved dust cup latch mechanism  38  are formed on the bottom wall  25  on each side of the suction motor/fan inlet conduit  24 . A conventional vacuum hose  27  is also provided on the upright handle assembly  12  and is in fluid communication with the cyclone separation module  18  for above-the-floor cleaning purposes. 
     The cyclone separation module  18  further comprises a cyclone separator  20  including an airstream inlet and outlet (not shown) and a dust cup assembly  28  located below the cyclone separator  20  and removably received in the dust cup recess  22 . The dust cup assembly  28  includes a dust cup  30  with a bottom discharge stand pipe  32 , a removable pre-motor filter chamber  34  with a center air passage  35 , a removable pre-motor filter  36  that is received within a removable pre-motor filter frame  33 , both of which are positioned between the pre-motor filter chamber  34  and the dust cup  30 , and a seal  39  for creating an air-tight seal between the pre-motor filter chamber  34  and the dust cup latch mechanism  38 . The bottom of the pre-motor filter chamber  34  is preferably formed with a circular recess  31  ( FIG. 5 ) that at least partially houses the seal  39  such that the seal  39  is removable with the dust cup assembly  28 . Exhaust air from the cyclone separator  20  flows through the discharge stand pipe  32 , passes through the pre-motor filter  36  and into the pre-motor filter chamber  34 , and out through the center air passage to the suction motor/fan inlet conduit  24 . 
     Referring now to  FIG. 3 , the dust cup latch mechanism  38  is comprised of a slide lock latch assembly  40 , a sealing conduit member  56 , and at least one linkage arm assembly  66  to translate horizontal sliding movement of the slide lock latch assembly  40  into vertical movement of the sealing conduit member  56 . The slide lock latch assembly  40  further comprises a slide lock housing  42 , an inner peripheral wall  43  defining an elongated aperture  44 , a pair of opposed L-shaped recesses  46 , an elongated depression  47 , a pair of engagement projections  48 , at least one mounting boss  49 , a securing aperture  50 , a corresponding securing aperture cover  52 , and a grip  54 . The engagement projections  48  are positioned on opposing sides of the slide lock latch housing  42  in offset positions. The slide lock housing  42  is generally rectangular-shaped with the elongated aperture  44  and elongated depression  47  on the top surface accommodating the sealing conduit member  56 . 
     The sealing conduit member  56  further includes a sealing member housing  58  with a flange  59  on the top surface thereof that forms a sealing surface  57 , an air passageway  60  extending through the sealing member housing  58 , at least one mounting boss  62 , and a sealing ring  64  that mates into a C-shaped groove  65  on the outer periphery of a lower portion  61  of the sealing member housing  58 . The lower portion  61  can further comprise a grate  63 , partially visible in  FIGS. 4A and 4B , that extends across the air passageway  60 . 
     As illustrated in  FIG. 3 , two opposed linkage arm assemblies  66  are coupled between the slide lock latch assembly  40  and the sealing conduit member  56 . Each of the linkage arm assemblies  66  comprise a link member  68  and two link pins  70 ,  72  coupled to the link member  68 . The link member  68  is an elongated piece, like a rod or lever, with the link pins  70 ,  72  attached near either end of the link member  68 . The pins  72  are pivotally mounted into the mounting bosses  49  of the slide lock housing  42  and the pins  70  are pivotally mounted into one of the mounting bosses  62  of the sealing member housing  58 . By this arrangement, translational movement of the slide lock housing  42  moves the sealing member  58  vertically as illustrated in  FIGS. 7 and 8 . At least one end of the link pins  70 ,  72  includes a knurled surface that allows a secure press fit into the corresponding components of the slide lock latch assembly  40  and the sealing conduit member  56 . The aforementioned link pin  70 ,  72  and link member  68  arrangement is only one of many potential translating horizontal movement of the slide lock latch assembly  40  into vertical movement of the sealing conduit member  56 . 
     To assemble the dust cup latch mechanism  38 , each linkage arm assembly  66  is coupled to the slide lock housing  42  by press fitting the pin  72  into one of the mounting bosses  49  and is also coupled to the sealing member housing  58  by press fitting the pin  70  into one of the mounting bosses  62 . In the assembled state, the sealing conduit member  56  is positioned at least partially within the elongated aperture  44  found on the slide lock housing  42 . The linkage arm assemblies  66  are positioned at least partially within the L-shaped recesses  46  found on the slide lock housing  42 . The L-shaped recesses  46  allow adequate clearance for the linkage arm assemblies  66  and mounting boss  62  protrusions as the dirt cup latch mechanism  38  is cycled through its latched and unlatched positions, which will be described in more detail below. 
     Referring now to  FIGS. 4A , and  4 B, the installation of the dust cup latch mechanism within the dust cup recess is shown. In the illustrated embodiment, the dust cup latch mechanism  38  is assembled to the upright handle assembly  12  by aligning at least one engagement projection  48  with at least one receiving channel  26  and fitting the elongated aperture  44  around the suction motor/fan inlet conduit  24  such that the sealing conduit member  56  is at least partially received within the suction motor/fan inlet conduit  24 , as shown in  FIG. 4A . Then the dust cup latch mechanism  38  is rotated to an installed position, shown in  FIG. 4B , such that the dust cup latch mechanism  38  is slidably captured by the at least one receiving channel  26 . Referring to  FIG. 4A , the dust cup latch mechanism  38  is rotated roughly 30 degrees from a reference datum I normal to the rear wheel axis in the pre-installation position to a reference datum II, which corresponds to the installed position. In  FIG. 4B , the dust cup latch mechanism  38  is in the installed position with engagement projections  48  slidably captured by the receiving channels  26 . 
     Once installed, the dust cup latch mechanism  38  can be secured using a single mounting screw. The securing aperture  50  located on the top surface of the slide lock housing  42  forms a retention screw slot and mates to a stepped or reduced diameter screw boss that receives a washer head retention screw. The particular washer head mounting arrangement is not germane to the invention and will not be shown or further described herein, suffice it to say that the receiving channels  26  in the bottom wall  25  of the dust cup recess  22 , together with the washer head screw mounting arrangement, and securing aperture  50  retain the dust cup latch mechanism  38  while adequately allowing for horizontal sliding movement. 
     Referring to  FIGS. 2 ,  5  and  6 , the dust cup latch mechanism  38  is mounted to the upright handle assembly  12  such that the slide lock housing  42  is permitted to slide horizontally in and out on the flat bottom wall  25  of the dirt cup recess  22  in a straight path. The grip  54  on the front portion of the slide lock housing  42  allows the user to pull and push the slide lock housing  42  as required and performs in the same functional manner as a drawer pull. The sealing conduit member  56  extends through the suction motor/fan inlet conduit  24  so that the flange  59  rests on the upper edge of the suction motor/fan inlet conduit  24  and the lower portion  61  fits beneath the bottom wall  25  of the dust cup recess  22 . The elongated aperture  44  and elongated depression  47  on the top surface of the slide lock housing  42  accommodate the sealing conduit member  56  such that it may move vertically as the slide lock housing  42  moves horizontally. The elongated aperture  44  can be generally oval in shape so that the slide lock housing  42  can move laterally relative to the sealing conduit member  56 . The elongated aperture  44  also has clearance for the air passageway  60  within the sealing member housing  58  that fluidly connects the suction motor/fan inlet conduit  24  to the dust cup assembly  28 . The two L-shaped recesses  46  have clearance to accommodate rotation of the linkage arm assemblies  66  during latch mechanism use. The outlet end of the center air passage  35  rests on the upper sealing surface  57  of the sealing member housing  58 . 
       FIGS. 5 and 7  show the dust cup latch mechanism  38  in its engaged or latched position, in which the sealing conduit member  56  is raised to its uppermost position, in turn, raising the dust cup assembly  28  to secure the upper end of the dust cup  30  against the bottom end of the of the cyclone separator  20 , thereby compressing the seal  39 , and sealing ring  64  for efficient vacuum operation with minimal leakage. In the latched position, the sealing surface  57  of the sealing conduit member  56  is pressed against the bottom of the pre-motor filter chamber  34  and the flange  59  rests atop the upper surface of the slide lock housing  42 . The dust cup latch mechanism  38  is moved to its latched position by pushing the slide lock latch assembly  40  inward, i.e. towards the rear wall  23  of the dust cup recess  22 . 
       FIGS. 6 and 8  show the dust cup latch mechanism,  38  in its disengaged or unlatched position, in which the sealing conduit member  56  is lowered, which accordingly lowers the dust cup assembly  28  out of engagement with the cyclone separator  20  to rest on the sealing conduit member  56  and the top surface of the slide lock latch assembly  40 . The dust cup assembly  28  can then be removed as a unit from the vacuum cleaner  10  by simply lifting/pulling it out of the dust cup recess  22 . In the unlatched position, the linkage arm assemblies  66  are rotated towards the rear wall  23  which subsequently forces the sealing conduit member  56  to move downward against the slide lock latch assembly  40 , with the flange  59  at least partially received by the elongated depression  47 . 
     The dust cup latch mechanism  38  is moved to its unlatched position by pulling the slide lock latch assembly  40  out from the from the rear wall  23  of the dust cup recess  22  to the limit of its travel. In the illustrated embodiment, the travel distance of the slide lock latch assembly  40  is controlled by the length of the linkage arm assemblies  66  and the securing aperture  50 . As the slide lock latch assembly is pulled horizontally, the link pin  72  moves with the slide lock housing  42 . The action of the link pin  72  is transmitted to the link pin  70  by virtue of the link member  68 ; however, because horizontal movement of the sealing conduit member  56  is generally prevented by the suction motor/fan inlet conduit  24 , the movement of the sealing conduit member  56  will be almost entirely vertical. 
     Referring to  FIGS. 7 and 8 , the dust cup latch mechanism  38  incorporates a natural detent by virtue of the “over-center” pin and linkage arrangement. When in the latched position ( FIG. 7 ), the linkage members  68  rotate slightly beyond vertical such that the linkage arm assemblies  66  and dust cup latch mechanism  38  become naturally retained or locked until the user intentionally releases the dust cup latch mechanism  38  by pulling the slide lock latch assembly  40  outward to move to the unlatched position ( FIG. 8 ). The locking action of the “over-center” pin and linkage arrangement is also aided by the compressed seal  39 , which tends force the dust cup assembly  28  away from the sealing conduit member  56  in the latched position, thereby naturally tending to rotating the linkage arm assemblies  66  to a position in which the linkage members  68  are not vertical. 
     It will be understood that the disclosed embodiments are representative of presently preferred forms of the invention, but, are intended to be illustrative rather than definitive of the invention. The illustrated upright vacuum cleaner is but one example of the variety of cyclone-separating type vacuum cleaners with which this invention or some slight variant can be used. Reasonable variation and modification are possible within the forgoing disclosure and drawings without departing from the scope of the invention which is defined by the appended claims.

Technology Classification (CPC): 8