Abstract:
A separator for use in separating larger rocks from smaller rocks and soil in which the upper rear support includes a connecting member allowing the sizing members to be adjusted to reject different minimum sizes, and in which the connecting member is recessed to protect it from damage during transport.

Description:
This invention relates to rock and soil separation and classification equipment, and in particular to a type of device referred to as a “grizzly” separator. A grizzly separator is a widely used piece of equipment in the construction and earth-moving fields. A grizzly normally consists of a rectangular base 3 to 5 feet tall with a row of parallel, angled members mounted on top of the base. The angled members are spaced apart a predetermined distance, and permit dirt and smaller rocks to pass through and accumulate beneath the device. Larger rocks are deflected downwardly along the angled members to a separate collection area outside of the base. Grizzlies can come in a variety of sizes, and are normally portable from site to site. 
   Grizzlies are used in construction to separate and classify dirt and rock as it is excavated during construction. The dirt and smaller rocks are reserved and used for backfill either on site or elsewhere. The larger rocks, which cannot be used for backfill under most building codes, are used for other purposes or disposed of off site. Different job specifications and building codes specify different maximum rock sizes that can be incorporated into fill dirt, and grizzlies therefore are supplied with a variety of spacing distances between the angled members. In some instances grizzlies are designed to permit adjustment of the spacing between the angled bars. 
   Grizzlies are subjected to very harsh use. Bucket loads of large rocks and dirt are dumped on them. As mentioned above, grizzlies are often transported from site to site. They are normally lifted by means of a back hoe or forklift that can bend or otherwise damage the bar adjustment mechanisms. Damage to the adjustment mechanisms can result in the bars not being movable as required, and take the grizzly out of service for repair. 
   As a result, a need remains for an improved sizer/separator in which the angled bars can be adjusted, and in which the adjustment mechanism is protected against damage during use and transportation. The present invention meets the need for an improved sizer/separator, as will be described in detail by reference to the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a front view of a separator according to a preferred embodiment of the present invention. 
       FIG. 2  shows a side view of a separator according to a preferred embodiment of the invention. 
       FIG. 3  is a cross-sectional view of the upper rear support. 
       FIG. 4  shows an enlarged side cross-sectional view of the attachment of the upper end of an angled sizing bar. 
       FIG. 5  shows an enlarged side cross-sectional view of the attachment of the lower end of an angled sizing bar. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now to  FIGS. 1-4 , a sizing separator according to a preferred embodiment of the invention is shown generally at  10 . Separator  10  includes front wall  12  and side walls  14  and  16 . An angled flange  18  extends along the upper edge of front wall  12 . An upper rear support  20  extends between side walls  14  and  16 . Referring to  FIG. 3 , upper rear support  20  includes three portions: an upper member  22 , a connecting member  24 , and a lower member  26 . Connecting member  24  is located between upper member  22  and lower member  26 , and is recessed, providing particular advantages that will be described below. 
   A number of sizing members  30  are mounted at an angle between front wall  12  and upper rear support  20  as shown. Sizing members  30  are spaced apart a predetermined distance to separate larger rocks from smaller rocks and soil as described above. Each sizing member includes an upper flange  32  and a lower flange  34 . Upper flange  32  is supported on the upper surface of upper rear support  20 , and is bolted to connecting member  24  using a series of holes  35 . Lower flange  34  is supported on angled flange  18 , and is bolted to the upper portion of front wall  12 , using a series of holes  36  provided for that purpose. A lower protective beam  17  is located below flange  18 . The spacing of the sizing members is adjustable by removing the bolts securing the upper and lower flanges of each sizing member, and moving the sizing members closer or farther apart as desired, then bolting the upper and lower flanges in place. In the preferred embodiment the spacing can be adjusted in 1″ increments, although the invention is not limited to any particular spacing of the sizing members. 
   Referring again to  FIGS. 3 and 4 , the upper rear support  20  will be described in greater detail. Upper rear support  20  includes an upper member  22 , a lower member  26 , and a recessed connecting member  24  in between. In normal use, a separator of this type is normally transported by being lifted onto a trailer using a forklift or backhoe. The forklift or backhoe normally lifts the separator by placing its bucket or tines  40  under upper rear member  20 , or under angled flange  18 . In other separators, upper rear support  20  does not include a lower member  26 , or a lower protective beam  17 , leaving connecting member  24 , angled flange  18 , and bolts  38  exposed to the bucket or forks of the backhoe. As a result, the bolts holding the upper flange  32  to upper rear support  20  and lower flange  34  to angled flange  18  are often damaged, making it very difficult to remove bolts  38  to adjust the sizing members. Applicant has discovered that this problem can be avoided by protecting the connector portions with members  26  and  17 , as shown and claimed. While in the preferred embodiment the recessing of the connector is achieved by way of the assembly illustrated, the invention is not intended to be so limited. Those of skill in the art will recognize that modifications in detail and arrangement are possible without departing from the scope of the following claims.