Abstract:
A double walled container is provided by an inner container that is fitted within an outer container. End flaps are provided on the outer container for engaging the inner container and closing the gap between the inner container and the outer container. The method involves lifting the inner container out of the outer container, removing the grease from the inner container, and inserting the outer container back into the inner container.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a method and apparatus for storing grease. 
   Currently grease is stored at various establishments in a single-walled container. Periodically a truck comes to the container, lifts it by chains, and dumps the contents into a large container in the truck. On some occasions, particularly in winter, the container is first dipped in hot water to loosen the grease from the side walls of the container before dumping it into the larger container of the truck. 
   Single walled containers are susceptible to developing leaks at the site where the containers are stored. Therefore it is desirable to provide a double-walled container. 
   Double-walled containers have been provided, but such containers require the replacement of the single wall containers. It is desirable to provide an outer container which can be combined with an inner container so that the present single-walled containers can be used. 
   Therefore, a primary object of the present invention is the provision of a method and apparatus for storing grease. 
   A further object of the present invention is the provision of a method and apparatus for storing grease which utilizes a double wall construction so as to minimize the spillage of grease at the site where the container is located. 
   A further object of the present invention is the provision of a method and apparatus for storing grease which utilizes an outer container that can be combined with present single wall containers to provide a double wall container. 
   A further object of the present invention is the provision of a method and apparatus for storing grease which is economical to manufacture, durable in use, and efficient in operation. 
   BRIEF SUMMARY OF THE INVENTION 
   The foregoing objects may be achieved by an outer container for receiving an inner container having first and second opposite inner container end walls, each of which comprises a lower pin and an upper pin extending outwardly. The outer container comprises a container box comprising first and second outer container end walls, a front outer container wall, a rear out container wall, and an outer container floor enclosing an outer container chamber having an open upper end. The outer container chamber is of a size to permit the inner container to be inserted therein through the open upper end. First and second flaps are hinged to the first and second outer container end walls respectively adjacent the open upper end for pivotal movement about first and second horizontal axis respectively. The flaps pivot from an open position wherein the first and second flaps are free from covering relation over the open upper end of the outer container box to a closed position wherein the first and second flaps each partially cover the open upper end of the outer container box. 
   According to another feature of the present invention a notch is formed in each of the first and second flaps. Notch covers pivotally mounted to the first and second flaps are pivotal from an uncovered position free from covering relation over the first and second notches respectively to a covered position in covering relation over the first and second notches respectively. 
   According to another feature of the invention a plurality of guide cams are positioned within the open upper end of the container box for engaging and guiding the inner container into the container chamber through the open upper end thereof. 
   According to another feature of the present invention a double wall container can be formed by combining the outer container having an outer container chamber with an inner container that is fitted within the outer container chamber. The result is that the inner container is positioned within the outer container chamber and includes first and second inner side walls facing first and second outer side walls, first and second inner end walls facing first and second outer end walls, and an inner bottom wall facing the outer bottom wall. The inner container has an inner container chamber for holding grease. Attachment members are connected to the inner container and a power lifter detachably connects to the attachment members for lifting the inner container out of the container chamber through the open upper end thereof. 
   The method of the present invention comprises taking the outer container and the inner container and positioning the inner container in registered alignment above the open upper end of the outer container. The inner container is then lowered into the outer container chamber through the open upper end thereof so that the first and second inner side walls face the first and second outer side walls, the first and second inner end walls face the first and second outer end walls, and the inner bottom wall faces the outer bottom wall. Grease is stored within the inner container chamber. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of the combined outer and inner containers providing a double walled container. 
       FIG. 2  is an exploded perspective view showing the lifting of the inner container out of the outer container. 
       FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to the drawings, a double walled container  10  includes an inner container  12 . The inner container  12  includes an inner front wall  14 , an inner rear wall  16 , an inner end wall  18 , another inner end wall  20 , and an inner bottom wall  22 . An inner top frame  24  extends around the upper perimeter of walls  14 - 20 . A pair of lift pins  26  extend outwardly from the top frame  24  adjacent the top of the inner container  12 . These lift pins enable a pair of chains  36  having hooks on the bottom thereof to be hooked around the lift pins  26  for lifting the inner container  12  upwardly as shown in  FIG. 2 . Normally these lift chains  36  are mounted on the spaced apart booms of a truck. 
   A pair of pivot pins  28  extend from the opposite end walls  18 ,  20  below the lift pins  26 . Pivot pins  28  are used for dumping the contents of the inner container  12  into a larger container within the truck. The pivot pins  28  are placed upon pivot rests (not shown) and the chains  36  are lowered, resulting in the inner container  12  tilting about the axis provided by pins  28  so as to remove the contents of the inner container  12  and dump them into the larger container within the truck. 
   A lid  30  includes a hinged door  32  therein which can be pivoted about hinge  34  for access to the interior of the inner container  12 . The lid  30  is removable during the operation for tilting and emptying the inner container  12 . As seen in  FIG. 3 , the inner container  12  is adapted to provide a quantity of grease or oil  38  coming from restaurants or other sources. 
   An outer container  40  includes an outer front wall  42 , an outer rear wall  44 , an outer end wall  46 , another outer end wall  48 , and a bottom wall  50 . Extending around the upper edges of walls  42 ,  44 ,  46  and  48  is an outer top frame  52 . Top frame  52  includes slanted frame ends  54 . The outer container  40  includes a cavity or outer container chamber  56  having an open upper end  58 . On the inside surfaces of the end walls  46 ,  48  are a pair of outer lift pins  60  which enable the outer container  40  to be lifted and moved to the desired location. Chains  36  can be used for this purpose. 
   Inside the outer container chamber  56  are four cam plates  62  which are located adjacent the four corners of the outer container chamber  56 . These cam plates are welded to the side walls  42 ,  44 , and help to guide the inner container  12  as it is lowered into the outer container chamber  56  from the position shown in  FIG. 2  to the position shown in  FIGS. 1 and 3 . This results in centering of the inner container  12  with respect to the end walls  46 ,  48 , and also with respect to the front and rear walls  42 ,  44 . 
   A pair of end flaps  64  are pivotally mounted to the slanted frame ends  54  of the outer top frame  52  by means of hinges  66 . The hinges  66  provide pivotal movement of the flaps  64  about horizontal axes which extend perpendicular to the longitudinal axis of the outer container  40 . At the outer edge of each flap  64  is a cover flange  68 . A cut out notch  70  is provided in the end flaps  64  in a central location and also is provided in the cover flanges  68 . Each end flap  64  includes a notch cover  72  which is mounted for pivotal movement about a notch cover hinge  74 . A notch cover handle  76  is used for pivoting the notch cover  72  about the hinge  74  from the position shown in  FIG. 1  to the position shown in  FIG. 3 . Each flap  64  includes a notch cover flange  78  which is pivotal to cover the space around lift pin  26  as shown in  FIG. 1 . The end flap  64  pivots approximately 270° from the position shown in  FIG. 1  in the direction of arrow  80  so that the notch cover flange  78  is positioned around the lift pin  26  and the cover plate or flap  64  is in covering relation over the cut out notch  70 . Also as can be seen in  FIG. 3  the cover flange  68  fits under the outer edges of the lid  30  so as to prevent water from entering the interior of the inner container  12  and also so as to prevent grease from splashing out of the inner container  12 . 
   It can be seen that the combination of the inner container  12  and the outer container  40  provides a double wall container when they are placed in combination as shown in  FIG. 3 . The end flaps  64  pivot into partial covering relation over the upper end  58  of the outer container chamber  56  so as to provide a double wall construction which minimizes the chances that the grease  38  will spill. 
   When it is desired to empty the inner container  10 , the truck is driven adjacent the double wall container  10  and the lift chains  36  are attached by hooks to the lift pins  26 . The lid  30  is removed. 
   Then the inner container  12  is lifted upwardly out of the outer container  40  as shown in  FIG. 2 . The truck can then submerge the inner container  12  in hot water if the contents are frozen so as to loosen the contents. Then the truck places the pivot pins  28  on pivot pin support and lowers the chains  36  so as to cause the inner container  12  to tilt and empty its contents into a larger container within the truck. 
   After emptying the contents of the inner container  12 , the lift chains are then lifted up again and the inner container is lowered into the outer container chamber  56 . The cams  62  help center the inner container as it is lowered. The hinge pins  28  pass between the cams  62 . Then the flaps  64  are folded from their positions shown in  FIG. 2  to their position shown in  FIG. 3  and the lid  30  is positioned in covering relation over the cover flanges  68  as shown in  FIG. 3  and results in a double wall container again which can be used to store grease and to minimize the chances of spillage. 
   In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstance may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims.