Abstract:
A filter housing having a lid that mates with the vessel portion. An arm with an inclined feature is secured to the lid and is movable with respect to the vessel portion. A rotational member that is rotatable with respect to the vessel portion engages the inclined feature. The rotational member is restrained from longitudinal movement so that rotation of it causes movement of the arm with respect to the vessel portion and therefore, moves the lid with respect to the vessel portion so that the lid may be separated from the vessel portion.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/320,124, filed Apr. 1, 2010, the disclosure of which is hereby incorporated by reference. 
    
    
     BACKGROUND 
     Large volume filtration vessels are very useful for filtering large amounts of fluid and, due to high pressures within such a vessel, the parts can be quite heavy. The heft of the parts can make changing individual filter elements within the vessel very difficult. Often, a lid or other cover must be lifted to reveal the individual elements within a filter vessel. The cover may be hundreds of pounds and, due to size, be quite awkward. Some large filter vessels may employ external means to lift the cover from the vessel such as an external crane. However, it is desirable to have an integrated system that allows for easy removal of the cover that is incorporated into the filter vessel itself. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a filter housing. The filter housing has a vessel portion and a lid which mates with the vessel portion. An arm is secured to the lid and is movable with respect to the vessel portion. The arm has an inclined feature. A rotational member engages the inclined feature. The rotational member is rotatable with respect to the vessel portion and restrained from longitudinal movement with respect to the vessel portion so that rotation of the rotational member relative to the arm causes longitudinal movement of the arm and separation of the lid from the vessel portion. 
     In one aspect of the invention, the inclined feature on the arm may be threads. In this case, threads on the rotational member mate with the threads on the arm. 
     In another aspect of the invention, the inclined feature on the arm may be inclined slots. In this case a pin engages at least one slot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a first embodiment of the filter housing; 
         FIG. 2  is a perspective view of the filter housing shown in  FIG. 1  with the lid in the lowered position; 
         FIG. 3  is a perspective view of the filter housing shown in  FIGS. 1 and 2  with the lid in a raised position, and the lid not being turned with respect to the vessel portion of the housing; 
         FIG. 4  is a perspective view of the filter housing shown in  FIGS. 1-3  with the lid in a raised position, and the lid being turned with respect to the vessel portion of the housing; 
         FIG. 5  is an exploded perspective view of the filter housing shown in  FIGS. 1-4 ; 
         FIG. 6  is a top view of the ratchet housing and ratchet gear; 
         FIG. 7  is an exploded perspective view of another embodiment of the filter housing; 
         FIG. 8  is an exploded perspective view of the filter housing shown in  FIG. 7  with the handle of the rotational member in the same position as in  FIG. 7 , which corresponds to the zero degree position; 
         FIG. 9  is an exploded perspective view of the filter housing shown in  FIGS. 7 and 8  with the handle in the ninety degree position; 
         FIG. 10  is an exploded perspective view of the filter housing shown in  FIGS. 7-9  with the handle in the 180 degree position; 
         FIG. 11  is a sectional view of the arm taken about line  11 - 11  in  FIG. 12 ; and 
         FIG. 12  is a perspective view of the arm shown in  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
     The filter housing  10  of the present invention has a vessel portion  12  and a lid  14  that is sealingly matable to the vessel portion  12 . The lid  14  is typically made of steel and, depending on the size of the housing, can be extremely heavy. The lid has retainer brackets  16  around the periphery that are designed to accept clamps  18  that are used to secure the lid  14  to the vessel portion of the housing  10  when it is in use. The lid has an arm  20  that is secured to a mounting bracket  24  on the lid  14 . The arm  20  may be joined to the bracket  24  by use of a press fit and bolt, or may be mounted with a bolt  26  and/or pin  28 . The arm  20  and lid  14  are movable relative to the vessel portion  12  and both move together. The arm  20  is typically made of steel pipe and has an inclined feature. 
     In one embodiment of the invention, the inclined feature on the arm  20  is threads  30 . The threads  30  extend along a lower portion of the arm  20 , as shown in  FIG. 1 . The arm  20  includes antirotation slots  32  within the threaded portion of the arm  20  that are best seen in  FIG. 5 . The arm  20  is held adjacent to the vessel portion  12  by upper and lower brackets  34 ,  36 . The upper and lower brackets  34 ,  36  are welded to the side of the vessel portion  20  and have bushings  38  fastened to their upper surfaces as can be seen in  FIGS. 2-4 . The bushings  38  have an inner diameter that accepts the arm  20  and allows movement of the arm  20  within the bushings  38 . Thus, longitudinal and rotational movement of the arm  20  is possible with respect to the vessel portion  12 . The lower bracket  36  has holes  40  on both sides for accepting a removable antirotation pin  42 . The antirotation pin  42  is removable and also extends through the antirotation slots  32  within the arm. The exploded view shown in  FIG. 5  illustrates how these parts are assembled. Thus, the antirotation pin  42  provides a selective locking of the arm  20  with respect to the vessel portion  12 . 
     A rotational member  46  rests against the bushing  38  on the lower bracket, as shown in  FIG. 1 . The rotational member  46  includes a ratchet housing  47  that contains a ratchet gear  48 . The ratchet gear  48  has a threaded bushing  50  that is mounted to the ratchet gear  48  with bolts  49 . The threaded bushing  50  has internal threads that match the threads  30  on the arm  20 . The ratchet housing  47  includes a reversible spring loaded pawl  52 . A spring  53  urges the pawl  52  into teeth  54  on the ratchet gear  48 .  FIG. 6  shows how the pawl  52  is angled to catch within the teeth  54  in one direction and slide over the teeth  54  in the opposite direction. A knurled thumb wheel  58  is attached to the pawl  52  and has a rib  60  for engaging a notch  62  in the ratchet housing  47 . When the wheel is turned 180 degrees, the direction of the pawl  52  is reversed and, as can be seen by one skilled in the art, the direction the ratchet gear  48  will turn will be reversed. A handle  66  extends from the ratchet housing  47 . 
     When the handle  66  is used to turn the ratchet housing  47  with the pawl  52 , as shown in  FIG. 6 , the ratchet gear  48  and threaded bushing  50  will be rotated in a clockwise direction as viewed in  FIG. 6 . When the antirotation pin  42  is installed in the lower bracket  36 , the arm  20  will be prevented from rotating, but will be able to move longitudinally. Rotating the ratchet housing  47  in a ratcheting motion will move the entire rotational member  46  downward on the arm  20 . Thus, the arm  20  will be urged upward because the rotational member  46  rests against the lower bracket  36  that is fixed to the vessel portion  12 . 
     The antirotation pin  42  may be removed from the lower bracket  36  and inserted within an aperture  70  in the threaded bushing  50 . When the aperture  70  in the treaded bushing  50  is aligned with the antirotation slots  32 , as shown in  FIG. 3 , the antirotation pin  42  can be inserted through the antirotation slots  32  and the aperture  70 . This locks the threaded bushing  50  and ratchet gear  48  together. As such, when the handle  66  is rotated counterclockwise from its position in  FIG. 3 , to its position shown in  FIG. 4 , the lid will be turned ninety degrees. 
     In another embodiment, the inclined feature on the arm  70  is inclined slots  72  on opposite sides. The slots  72  have inclined portions  74  and flat portions  76  that are not inclined. The middle of the flat portion  76  of each slot  72  is approximately ninety degrees from the top  73  of the inclined slot  72 . Locking holes  77  are located below the slots  72 . As will become apparent from the foregoing description, only one locking hole  77  is needed, but for symmetry and manufacturability two locking holes  77  are included 180 degrees opposite each other in the arm  70 .  FIG. 7  shows an exploded view of the arm  70  in relation to the vessel portion  12 . As in the previous embodiment, bushings  38  are mounted on the upper and lower brackets  34 ,  36 . The arm  70  also has antirotation slots  80  that accept an antirotation pin  82 . The antirotation pin  82  is held fixed with respect to the vessel portion  12  through the holes  40  in the lower bracket  36  and may be removed. The rotational member  86  has a central aperture  87  through which the arm  70  of this embodiment passes. A locking pin  88  is biased into the central aperture  87  with a spring  90 . A retraction tab  91  is connected to the locking pin  88  and, when it is pulled in a direction away from the central aperture  87 , the locking pin  88  is retracted. A lift pin  92  having a head  93  extends across the central aperture  87  and is received within the inclined slots  72 . A handle  94  extends from the rotational member  86 . 
       FIGS. 8-10  show various positions of the parts connected to the arm  70 . Angular position in these FIGS. are shown as labeled with zero degrees being the position of the handle  94  in  FIG. 8 , ninety degrees being the position of the handle  94  in  FIG. 9 , and 180 degrees being the position of the handle  94  in  FIG. 10 . Movement of the handle  94  through these positions moves the arm  70  and therefore raises the lid  14  and is best explained by discussing the positions of the various parts connected to the arm  70  in the positions mentioned above. 
     In  FIG. 8 , with the handle  94  in the zero degree position, the head  93  of the lift pin  92  is at ninety degrees, and the top  73  of the inclined slot  72  is at ninety degrees. In this position, the antirotation pin  82  is in place in the lower bracket  36  and extends through the antirotation slots  80 . The antirotation slots  80  are aligned across the zero and 180 degree positions. 
     As the handle is turned clockwise, as viewed from above from the position in  FIG. 8  to the position in  FIG. 9 , the lift pin  92  rotates and the arm  70  remains locked due to the antirotation pin  82 . As the lift pin  92  is rotated by movement of the handle  94 , the lift pin  92  moves down the incline and raises the arm  70  as the rotational member  86  presses against the bushing  38  on the lower bracket  36 . The motion of the handle  94  from zero to ninety degrees raises the arm until the lift pin  92  reaches the flat portions  76  of the slots  72 . At the ninety degree position of the handle  94 , as shown in  FIG. 9 , the locking pin  88  is urged into the locking hole  77  and the lid  14  is raised to its maximum height above the vessel portion. The locking hole  77  on the opposite side will never be positioned to receive the locking pin  88  but, as previously mentioned, for symmetry and manufacturability purposes an opposite locking hole  77  is included. This means an assembler installing the arm  70  will not have to check for the locking hole  77  to be located at the ninety degree position during assembly as long as the slots  72  and  80  are correctly positioned. 
     With the locking pin  88  in the locking hole, as is the case in the ninety degree position of the handle shown in  FIG. 9 , the antirotation pin  82  may be removed from lower bracket  36 . When this is done, moving the handle from the ninety degree position to the 180 degree position, shown in  FIG. 10 , will rotate the lid  14  and arm  70  ninety degrees. 
     When a user of the filter housing  10  of this invention wishes to raise the lid  14 , made according to the embodiment shown in  FIGS. 1-5 , he will move the handle  66  in a ratcheting motion until the lid  14  is raised to a desired height. With the lid  14  in the raised height, the user will ratchet the handle  66  until the aperture  70  in the threaded bushing  50  is aligned with the antirotation slots  32 . He will then pull the antirotation pin  42  from the lower bracket  36  and insert it through the aperture  70  and through the antirotation slots  32 . He will turn the handle  66  and rotate the lid. After the user has changed filter elements in the vessel portion  12  of the housing  10 , he will use the handle  66  to rotate the lid  14  to a position directly over the vessel portion  12 . In that position, the user will then remove the antirotation pin  42  from the aperture  70  and install it into the lower bracket  36  through the holes  40  in the lower bracket  36  and the antirotation slots  32 . The user pulls back the thumb wheel  58  to dislodge the rib  60  from the notch  62  and rotate it 180 degrees so that the rib  60  is again in the notch  62 . This will cause the pawl  52  to be facing the opposite direction from that shown in  FIG. 6 . Thus, moving the handle  66  will rotate the threaded bushing counterclockwise, as viewed from above, and lower the lid  14 . Once the lid  14  is lowered, the clamps  18  are tightened against the lid as shown in  FIG. 1 . 
     A user raising the lid  14  on a housing  10  made according to the embodiment shown in  FIGS. 7-10  will begin with the handle  94  in the zero degree position shown in  FIG. 8 . The user will then rotate the handle  94  toward the ninety degree position shown in  FIG. 9 . At the ninety degree position the locking pin  88  will engage into the locking hole  77  in the arm  70 . With the handle  94  in the ninety degree position, the user will remove the antirotation pin  82  from the lower bracket  36 . The user will move the handle from the ninety degree position to the 180 degree position and this will turn the lid  14  ninety degrees. To lower the lid  14 , the user will rotate the handle from the 180 degree position to the ninety degree position shown in  FIG. 9 . In this position, he will reinstall the antirotation pin  82  in the lower bracket  36 . The user will pull the retraction tab  91  toward the handle  94  to pull the locking pin  88  from the locking hole  77 . While holding the retraction tab  91  he will rotate the handle  94  slightly before releasing the tab  91  so the locking pin  88  does not reengage the locking hole  77 . As the handle  94  is rotated from ninety degrees to the zero degree position shown in  FIG. 8 , the lid  14  will be lowered to rest on the top of the vessel portion  12  of the housing  10 . The clamps  18  are then tightened against the lid  14 . 
     The invention is not limited to the details given above, but may be modified within the scope of the following claims.