Abstract:
A manually rotatable composter  100  including a container  12  having an opening  110  for receiving compostable material. The container includes an outer surface having end sections attached thereto and a plurality of steps  20  capable of accommodating a hand or foot of a person in order to apply a rotational force to manually rotate the container. The steps can be in the form of pockets or protrusions. Indicia  28  can also be included for indicating the rotational state of the composer.

Description:
This application claims the benefit of U.S. provisional application 60/053,355, filed Jul. 22, 1997 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to composters, and more particularly to composters that are manually rotatable to facilitate composting. 
     BACKGROUND OF THE INVENTION 
     Composters are used to rapidly and efficiently decompose organic matter such as leaves, grass clippings, household waste, and the like. The composting process is facilitated by periodically breaking up and mixing the compost material within the composter. This can be accomplished directly, such as manually with a shovel, or by rotating the composter. However, manually rotating a composter having large amounts of compost material tends to be very difficult, especially when a significant portion of the originally loose organic matter has decomposed into denser compost material. 
     There are several prior art designs for rotatable composters. However, prior art rotatable composters lack the appropriate leverage means necessary for a person to easily manually rotate the composter when it contains relatively dense compost material. For example, U.S. Pat. No. 5,288,146 (“the &#39;146 patent”) discloses a rotatable composter having a cylindrical body which is rotatable about its long axis, and which includes slots in the cylindrical body for collecting rainwater, and two-by-fours disposed along the length of the cylindrical body for providing structural rigidity. However, these slots and two-by-fours are not suitable as hand-holds or foot-holds for manually rotating the composter, and no mention is made of using them as such. 
     Another type of rotatable composter is disclosed in U.S. Pat. Nos. 5,501,978 and 5,345,620 (collectively, “the &#39;978 patent”). The &#39;978 patent discloses a rotatable aeration drum for a composting toilet. The drum includes diametrically opposing elongate indentations extending radially inwardly from the wall of the drum to assist in lifting solid waste matter within the drum during rotation of the drum. The drum is rotated via a handle connected to a gear which intermeshes with a cogwheel disposed about the perimeter at one end of the drum. While these indentations appear to resemble hand-holds or foot-steps, they are actually for facilitating mixing of the compost material within the drum when the drum is rotated via the handle. Moreover, the indentations are not accessible for manual rotation of the drum because the drum is enclosed in a housing. 
     A rotable composter is also described in U.S. Pat. No. 4,687,645, wherein the composter drum is mounted on a horizontal transverse axis at the drum&#39;s midpoint. The drum is held above the ground at a height sufficient to allow rotation of the drum without it hitting the ground. However, manual rotation of the drum is apparently accomplished by a person grasping the edges of the drum. This operation is not only awkward, but potentially dangerous because the composting material within the drum can rapidly shift, leaving the person in a difficult position to apply the appropriate counter-force needed to prevent the drum from rapidly rotating. 
     SUMMARY OF THE INVENTION 
     The present invention relates to composters, and more particularly to composters that are manually rotatable to facilitate composting. Such composters are difficult to manually rotate when the composter container holds substantial amounts of compost material. The present invention is a rotatable composter with steps (i.e., hand-holds or foot-holds) designed so as to allow a person to readily rotate the composter container even when it contains a large amount of relatively dense compost material. 
     Accordingly, one aspect of the present invention is a manually rotatable composter, comprising a container having an axis of rotation, an interior for receiving compostable material, and an outer surface. The container includes a plurality of steps, which are capable of accommodating a hand or foot of a person. These steps may each be a pocket in the outer surface extending radially inwardly toward the axis. Alternatively, the steps may each be a protrusion in the outer surface extending radially outwardly toward the axis. Thus, to rotate the composter, a person inserts a hand or a foot into or onto a step, and exerts a force substantially tangential to the outer surface of the container. By having such a secure hand-hold or foot-hold, an amount of leverage sufficient to readily manually rotate the container is achieved. 
     In another aspect of the invention, the composter of the present invention includes a support member for supporting the outer surface of the container to permit the container to be rotated. This support member may be, for example, a pedestal. 
     In a further aspect of the invention, the composter of the present invention includes a support member for supporting the container at the axis of rotation to permit the container to be rotated. In this regard, the container may have a long dimension and a short dimension, and the container may be rotated about either axis 
     In another aspect of the invention, the composter of the present invention further includes indicia on the outer surface of the container for indicating the rotational state of the composter. Such indicia may be, for example, days of the week. If desired, each of the plurality of steps may be associated with a corresponding one of the indicia. Such indicia allows for the rotational state of the composter to be tracked over time, allowing for optimization of the composting process. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a first preferred embodiment of the rotatable composter of the present invention; 
     FIG. 2 is an end view of the composter of FIG. 1; 
     FIG. 3 is a side view of a second preferred embodiment of the rotatable composter of the present invention; 
     FIG. 4 is an end view of the composter of FIG. 3; 
     FIG. 5 is a side view of a third preferred embodiment of the rotatable composter of the present invention; 
     FIG. 6 is an end view of the composter of FIG. 5; and 
     FIG. 7 is a perspective view of a working example composter of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention relates to composters, and more particularly to composters that are manually rotatable to facilitate composting. With reference to FIGS. 1 and 2, composter  10  of the present invention comprises a container  12  having an outer surface  14  and ends  15   a  and  15   b . Container  12  is preferably rotationally symmetric in shape with a long dimension and a short dimension to facilitate rotation about an axis  16  along the long dimension, as shown. Container  12  includes a sealable opening (not shown) at one of ends  15   a  and  15   b  or in outer surface  14 , for depositing and enclosing compostable organic matter within the container. Surface  14  surrounds axis  16  and may extend parallel to axis  16  (i.e., have a cross-section that is constant in size and shape, like that of a cylinder) or may be curved with respect to axis  16  (i.e., like that of an ellipsoid, as shown). 
     Composter  10  also includes a plurality of steps  20 . Steps  20  may each be a pocket in surface  14  extending radially inwardly toward axis  16  wherein each pocket is formed by a continuous wall surrounding a bottom surface. Alternatively, steps  20  may each be a protrusion in surface  14  extending radially outwardly away from axis  16  wherein each protrusion is formed by a continuous wall surrounding the periphery of a top surface. In some cases, a given composter  10  may include both recessed and protruding steps  20 . Steps  20  may be formed directly in or on surface  14 , or may comprise separate structure attached to surface  14 . In any case, it is preferred steps  20  be capable of accommodating a hand or foot of a person. 
     In a preferred embodiment, steps  20  are located at or near the middle of container  12  and surround axis  16 . This location of steps  20  provides the best opportunity for obtaining the leverage needed to rotate container  12 . However, other locations for steps  20  are also encompassed by the present invention. 
     With continued reference to FIGS. 1 and 2, composter  10  preferably further includes a support member  24  for supporting container  12  so as to permit the container to be rotated about axis  16 . Support member  24  has a surface  25  that slidingly engages surface  14  of container  12 . The coefficients of friction of surfaces  14  and  25  are chosen so that container  12  may be relatively easily rotated with respect to support member  24 . Support member  24  may have various configurations including, for example, a pedestal configuration, as shown. 
     In the case where steps  20  are protrusions, it is preferred that support member  24  not interfere with the rotation of container  12 . This may be accomplished, for example, by providing support member  24  with an aperture  26 , as shown, through which protrusion-type steps  20  may pass during rotation of container  12 . Support member  24  may also include a ratchet member  27  which allows for rotation of container  12  only in one direction. This prevents container  12  from counter-rotating after it has been rotated in a particular direction. 
     Because rotatable composters are rotated to facilitate mixing, it is often useful to know the rotational state of the composter, i.e., when it was last rotated relative to a given position, and how much the composter was last rotated. Toward this end, composter  10  may further include indicia  28  provided on surface  14 , such as written words or symbols which allow a user to determine the rotational state of the composter. For example, as shown in FIG. 1, indicia  28  may be the days of the week. Preferably, indicia  28  are evenly distributed about axis  16  so that the spacing between any two indicia is substantially the same as the spacing between any other two indicia. In some cases it may be desirable to select the same number of steps  20  and indicia  28 , so that a step is associated with each indicia. Alternatively, indicia  28  may be a series of numbers, letters or other symbols. The specific number of indicia  28  preferably ranges from 5 to 10, but greater and lesser numbers of indicia are also encompassed by the present invention. 
     With reference now to FIGS. 3 and 4, composter  50  is a second preferred embodiment of the present invention. Composter  50  is the same as composter  10  of FIGS. 1 and 2, except that instead of container  12  being supported at surface  14 , e.g., by support member  24 , a support member  54  supports the container at axis of rotation  16 . Support member  54  includes horizontal shafts  56  each of which are journaled to a bearing  58  located at each of ends  15 a and  15   b  of container  12  along axis  16 . Bearings  58  allow for rotation of container  12  about axis  16 . Bearings  58  may also include a ratchet member  59  which allows for rotation of container  12  only in one direction. This prevents container  12  from counter-rotating after it has been rotated in a particular direction. 
     With reference now to FIGS. 5 and 6, composter  80  is similar to composter  50  of FIGS. 3 and 4, except that container  12  is rotatable about an axis  86  along the short dimension of the container. Also, bearings  58  are located on surface  14  so as to lie on axis  86 . Moreover, steps  20  are aligned along the long dimension of container  12  and surround axis  86 . 
     A working example of the rotatable composter present invention is now described. With reference to FIG. 7, there is shown a composter  100  similar to composter  10  of FIG.  1 . In composter  100 , container  12  includes an aperture  110  at end  15   a , and an interior  111 . Aperture  110  is sealable with a lid  112 . In addition, a portion of surface  14  includes an outer region  104  extending radially outwardly therefrom. Region  104  is polygonal in cross-section and includes a plurality of vertices  106  and faces  108 . Pocket-type or protrusion-type steps  20  are located in outer region  104  at vertices  106  extending along only a minor portion thereof. Composter  100  further includes indicia  28 , shown as words indicating the days of the week, inscribed on faces  108 . In a preferred embodiment, region  104  has a septagonal cross-section, with seven vertices  106  and seven faces  108 , one for each day of the week. Thus, a unique indicia  28  is associated with each step  20 . 
     The operation of the rotatable composter of the present invention is first described with reference to the working example shown in FIG.  7 . As the first step in operating composter  100 , the compostable material to be composted is placed into interior  111  of container  12  through aperture  110 . Then, aperture  110  is sealed with lid  112 . After a given amount of time passes, it will be advantageous to rotate container  12  of composter  100  to facilitate the composting process. Accordingly, a person (not shown) places a hand or foot into one of steps  20  (or two hands into respective steps  20 , or one hand and one foot into respective steps  20 , etc.) and exerts a force substantially tangential to surface  14 . Typically, this force is applied in a downward direction, although it may be applied in an upward direction if desired. 
     In operating composter  10 , a person determines the rotational state of the composter by examining the position of indicia  28  relative to a fixed location, e.g., an edge of support member  24 . For example, when indicia  28  represent the days of the week, the user rotates composter  10  so that the given day of the week is positioned in selected relation to the selected comparison location. 
     Prior to or after rotating container  12 , it may be desirable to add more compostable organic matter to the container. If so, lid  112  is removed and more vegetative matter or the like is added to interior  111  of container  12 , as described above. The rotation process is repeated every so often (e.g., daily), until the compostable organic matter within container  12  is substantially completely decomposed to compost material. The ability to track the rotational state of the composter over time allows for the optimization of the composting process. 
     Operation of the other embodiments of the composter of the present invention, i.e., composter  10 , composter  50  and composter  80 , proceeds substantially in the same manner described above with respect to composter  100 . As such, the description is not repeated for these embodiments. 
     An important advantage of the composter of the present invention is that steps  20  aid a user in rotating the composter a controlled amount in a controlled fashion. Also, the provision of indicia  28  aids a user of the composter in rotating the composter amount that optimizes the composting process. With prior art composters, it tends to be difficult for a user to readily determine when, and the amount to which, the composter was last rotated. 
     While the present invention have been described in connection with preferred embodiments and a working example, it will be understood that it not so limited. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined in the appended claims.