Abstract:
A lifting attachment for lifting paint containers into and out of paint mixers of the type supported by a generally horizontal surface and including at least one side, the lifting attachment having a pair of rigidly connected arms, each including a proximal end pivotably connected to a paint mixer and a distal end extending beyond the side of the paint mixer, a mechanical link in the form of a strap and hook connected to a cross member intermediate the proximal and distal ends of the arms for lifting and lowering a paint bucket into and out of the paint mixer and a pair of gas springs connected between the paint mixer and the lifting arms for urging the lifting attachment vertically upwards.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of application Ser. No. 10/235,978, filed Sep. 5, 2002, now U.S. Pat. No. 6,729,754 B1, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Powered mixers are popular in retail outlets selling paint. When the paint is vended in five gallon buckets (or similar containers), considerable effort required to lift the buckets into and out of the mixers. One form of assistance has been to provide a roller conveyor in front of one version of a paint mixer to raise the bucket to a height at or near that necessary to slide the bucket into the mixer. However, with “drop-in” type paint mixers further lifting effort is still required to move the bucket between the conveyor and mixer. The present invention reduces this effort and provides an attachment that makes it easier to lift five gallon buckets or similar containers of paint into and out of “drop-in” type paint mixers. The present invention will accomplish its function whether or not a conveyor is present in front of the mixer. 
     SUMMARY OF THE INVENTION 
     In one form, the present invention is a lifting attachment apparatus for lifting paint containers into and out of paint mixers, the attachment apparatus in combination with the paint mixer and including a paint mixer supported by a generally horizontal surface and including at least one side; at least one lifting arm including a proximal end movably connected to a supporting structure and a distal end extending beyond the side of a paint mixer; a mechanical link connected to the at least one lifting arm intermediate the proximal and distal ends for lifting and lowering a paint container into and out of the paint mixer; and spring means connected to the at least one lifting arm for urging the at least one lifting arm upwards. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view from the front and above of a conveyor and paint mixer with the lifting attachment of the present invention shown with a paint bucket in the mixer. 
         FIG. 2  is a side elevation view of the mixer and attachment of FIG.  1 . 
         FIG. 2   a  is an enlarged view of a portion of  FIG. 2  showing the lifting attachment assembly. 
         FIG. 2   b  is a front elevation view of the mixer and attachment of FIG.  1 . 
         FIG. 2   c  is an exploded view of a weldment subassembly with associated parts useful in the practice of the present invention. 
         FIG. 2   d  is an exploded view of the lifting attachment assembly. 
         FIG. 3  is a view similar to  FIG. 1 , except with the paint bucket on the conveyor and the lifting attachment connected to the bucket in a first position. 
         FIG. 4  is a view similar to that of  FIG. 3 , except with the lifting attachment raised to lift the bucket to a second position. 
         FIG. 5  is a view similar to that of  FIG. 4 , except with the bucket moved laterally and rotated to a position in which the bucket is about to be received in the mixer while still supported by the lifting attachment. 
         FIG. 6  is a view similar to that of  FIG. 5 , except with the bucket fully received in the mixer and with the lifting attachment lowered to a position just prior to release from the bucket. 
         FIG. 7  is a view similar to  FIG. 3  except without a conveyor and with the bucket elevated slightly above the surface supporting the paint mixer. 
         FIG. 8  is a view similar to that of  FIG. 5 , except with a single handle. 
         FIG. 9  is an alternative embodiment showing a single arm version of the lifting attachment useful in the practice of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the Figures, and most particularly to  FIG. 1 , a paint mixer  10 , together with a lifting attachment  12  useful in the practice of the present invention, may be seen. Paint mixer  10  is preferably a Model 5305, available from Red Devil Equipment Co., 7150 Boone Avenue North, Suite 100, Brooklyn Park, Minn. 55428. In the past, it was necessary to manually lift a five gallon paint container or bucket  14  into and out of the mixer. The lifting attachment  12  of the present invention reduces the effort required to move the paint container  14  into and out of the mixer  10 . Typically, a conveyor  16  is located in front of the mixer and preferably extends from a colorant dispenser or tinting station (not shown) to the mixer  10  to assist in moving the five gallon buckets  14  of paint from the tinting station to a mixing station at the mixer. It is to be understood that additional conveyor segments are typically present to extend the length of the conveyor  16  as desired. It is also to be understood that bucket  14  has a bail  18  and handle  20 . A door or hood  22  is pivotably attached to mixer  10  and is closed prior to operating mixer  10 . As may be seen most clearly in  FIG. 2 , both the mixer  10  and conveyor  16  are preferably supported on a floor or other horizontal surface  24 . Conveyor  16  preferably is a non-powered conveyor having a plurality of rollers  26  supported by a frame  28 , and may include multiple sections similar or identical to the section shown in the figures to transport paint containers  14  towards and away from mixer  10 , as desired. 
     Referring now also to  FIGS. 2   a ,  2   b ,  2   c , and  2   d , the lifting attachment  12  preferably includes an arm weldment  30  having a pair of arms  32 ,  34 , and a cross brace  36  welded in an “H” form with two pairs of diagonal offsets  38 ,  40  and  42 ,  44 . The first pair of diagonal offsets  38 ,  40  are arranged in arms  32 ,  34 , respectively to conform to a sloping portion  46  of a front side  48  of mixer  10 . As used herein, “side” is to be understood to include the front surface of the mixer  10 , encompassing one or both of the sloping portion  46  and the vertically oriented parts of side  48 . The second pair of diagonal offsets  42 ,  44  reduce the width between a pair of manually graspable handles  50 ,  52 . Each of arms  32  and  34  are preferably formed of ⅛×1.0×1.0 inch cold rolled hollow steel tubing having a square cross section. The cross brace  36  is preferably formed of 16 gauge 0.50×1.00 inch cold rolled hollow steel tubing. The handles  50 ,  52  are preferably formed of ⅞ OD cylindrical steel tubing extend from proximal ends of arms  32  and  34 , respectively, and each has a conventional vinyl handle grip  57  received thereon. A pair of circular cross section pieces of ⅞ OD steel tubing form a pair of journals  58 ,  60  at distal ends of the arms  32 ,  34 , respectively, to allow the arm weldment  30  to pivot with respect to its mounting, to be described infra. A pair of cross section pieces of ⅞ OD steel tubing form projections  62 ,  64  to carry bumpers  65  which limit downward travel of the lifting attachment  12  after installation. A pair of 1 inch wide, 6 gauge steel angle flanges  66  each have an ear  70  formed at an angle of 122 degrees to carry a bumper  69  to limit upward travel of the lifting attachment  12 . Bumpers  65  and  69  are conventional, with bumpers  65  preferably having a shore durometer of 40 and bumpers  69  preferably having a shore durometer of 70. A pair of 1 inch wide, 6 gauge steel gussets  72  each have an aperture  74  therein to receive an end of a gas spring  76  to provide lifting support for lifting attachment  12 . Gas springs  76  are preferably rated at 80 lbs. and preferably have an operating range of 7.09 to 9.09 inches, with metal ball ends, each having a conventional threaded stud for attachment to the lifting attachment  12  using conventional washers and nuts. 
     A 2 inch wide strap of nylon webbing  77  carries a hook  78  sized and shaped to receive bail handle  20  on bucket  14 . The hook  78  is preferably formed of 7 gauge steel. As may be seen most clearly in  FIG. 2   c , webbing  77  preferably has a pair of loops  79  formed at each end of the strap by stitching the webbing to itself. One loop captures the hook  78 , and the other loop is received over a plate clamp  80 . The hook and webbing subassembly is preferably sized to enable the hook to release from the handle  20  when the lifting attachment is at or near the lowermost position. The hook and webbing subassembly is preferably secured to the cross brace  36  by a plate clamp  80 . As may be seen most clearly in  FIGS. 2   c  and  2   d , conventional nuts are preferably used to secure bumpers  69  and plate clamp  80  to the lifting attachment  12 . 
     Referring now most particularly to  FIGS. 2   a  and  2   d , a plate  82  has a first pair of tabs  84  welded thereto for securing the gas springs  76 , and further has a second pair of tabs  86  welded to the plate  82  to support the arms  32 ,  34  at the journals  58 ,  60 . A pair of end walls  90 ,  92  are similarly welded to plate  82 . Each of the tabs  84 ,  86  and end walls  90 ,  92  are to be understood to include conventional projections received in notches (not shown) in plate  82  for maintaining the respective locations of these parts as they are welded together. End walls  90 ,  92  each have an aperture  94  aligned with an aperture  96  in tabs  86  to receive a conventional shoulder bolt  98  to form a pivot in each of journals  58 ,  60 . A decorative sheet metal cover  100  is preferably received over plate  82  and attached to end walls  90 ,  92  via studs  102  received in slotted tabs  104  welded to cover  100 . A conventional nut (not shown) is received over each of studs  102  and tightened to secure cover  100  to the lifting attachment assembly  12 . 
     Referring now again most particularly to  FIG. 2   a , a plurality of studs  106  preferably project downward from plate  82  and are used to secure the lifting attachment assembly  12  to the mixer  10  in a conventional manner. 
     Referring now to  FIGS. 3 ,  4 ,  5  and  6 , the operation of the lifting attachment will be explained. In  FIG. 3 , a paint bucket  14  is shown located on the conveyor  16  just prior to insertion into the mixer  10 . At this position, the arms  32 ,  34  of the lifting attachment  12  have been manually lowered and the hook  78  has been manually engaged with the bail handle  20  of the bucket  14 . In  FIG. 4 , the lifting attachment has been manually elevated with the aid of the gas springs  76 , by grasping at least one handle grip  57  and raising assembly  12  until the bucket clears a bucket receptacle  108  in the mixer  10 . It is to be understood that cross brace  36  will move laterally, as well as vertically, as the assembly  12  is elevated, moving bucket  14  closer to receptacle  108  as the assembly is elevated. 
     In  FIG. 4 , the assembly  12  is nearly fully elevated, evidenced by close approach of bumpers  69  to plate  82 . At this time, the bucket  14  is positioned over the receptacle  108 , but is not aligned therewith. In  FIG. 5 , the bucket  14  is manually aligned with receptacle  108 , while attachment  12  is held in the fully elevated position. The lifting attachment is then lowered to the position shown in  FIG. 6 , using one or both handle grips  57 , while the bucket  14  slides into receptacle  108 , coming to rest as shown in FIG.  6 . The lifting attachment  12  is shown in  FIG. 6  positioned slightly above its lowermost position. This allows arms  32 ,  34  to be lowered to the lowermost position (not shown) at which time the bail handle  20  is released from hook  78 . The lifting attachment is then released from manual control, at which time it will return to the uppermost position similar to that shown in  FIGS. 4 and 5 , but with the bucket  14  remaining fully received in receptacle  108 . It is to be understood that the uppermost position will allow the lifting attachment to move (preferably about four inches in travel) higher than that shown in  FIGS. 4 and 5 , to enable the lifting attachment to rest in a position providing greater clearance to the mixer  10  than that shown in  FIGS. 4 and 5 . After the lifting attachment is elevated and released, door  22  is closed on mixer  10  and the paint is agitated by mixer  10 , after which the door  22  is opened and the process described above is repeated in reverse order to lift the bucket  14  from the mixer and return it to the conveyor  16 . 
     In an alternative arrangement, a paint bucket  14  may be located on the floor  24  in front of mixer  10 , where the lifting attachment  12  may be used to assist raising the bucket  14  from the floor and into and out of the mixer  10 . The conveyor  16  is absent from this arrangement. 
     Referring now most particularly to  FIG. 8 , an alternative embodiment of the present invention may be seen. In this embodiment, a single elongated handle  54  extends between the arms  32  and  34 . Handle  54  may have a vinyl grip thereon, similar to handles  50  and  52 . 
     Referring now to  FIG. 9 , a still further alternative embodiment of the present invention utilizes a single arm  110  replacing and performing the functions of arms  32  and  34 . Arm  110  may be made of stronger material, if desired, or may be made of larger cross section material, to adequately support the increased loading for a single arm embodiment. An increased capacity spring  112 , preferably doubling the force of spring  76 , (but with the same stroke) may be used in this embodiment. Alternatively a pair of springs  112 ,  114  may be used with ratings the same as springs  76 . In this embodiment, a yoke or Y-shaped member  116  may be used to support webbing  77 , and a single handle  118  is preferable, with a vinyl grip, if desired. 
     This invention is not to be taken as limited to all of the details thereof as modifications and variations thereof may be made without departing from the spirit or scope of the invention.