Patent Publication Number: US-8979009-B2

Title: Concrete crusher

Description:
FIELD OF INVENTION 
     The present invention relates to crushing devices and, more particularly, to a design for a concrete crusher, which includes a concrete gyratory shell. 
     BACKGROUND OF THE INVENTION 
     Gyratory crushers (or cone crushers) are well established machines that are used for crushing rocks, ore, and other materials. They are very large and their basic structure comprises a bowl shaped as a cone with the wider end of the cone near the top of the crusher. A conical head assembly is located on the axis of the bowl, and the head assembly is oriented so that its smaller dimension is at the top of the crusher. To perform the crushing action, independent motions are applied to the conical head assembly. The first is rotation and the second is gyration. 
     In the typical gyratory crusher, large material is fed into the top between the large opening of the bowl and the small end of the head assembly where the volume is largest. The gyration of the head assembly is furnished by an eccentric drive, the rotation is driven by a gear, and vertical support and minor vertical adjustment is furnished by a hydraulic support. All these parts are located at the bottom of the crusher at the bottom of the conical head assembly. The combination of the rotation and the gyration applies forces that crush the pieces of material, and they fall lower into the reduced space within the bowl as they are reduced in size. Ultimately the material leaves the crusher through openings at the bottom of the crusher. 
     A typical gyratory crusher has a thick metal shell that is typically cast. It can be appreciated that these large castings can require long lead times, and a result only a limited number of potential suppliers are available. In addition, the thick metal shell is expensive. 
     Accordingly, in accordance with an exemplary embodiment, a concrete gyratory shell can be used to replace a significant portion of the casting needed. It can be appreciated that a concrete gyratory shell can replace the thick metal shell, and which is easier to manufacture, at a lower cost and with reduced lead time. 
     SUMMARY OF THE INVENTION 
     In accordance with an exemplary embodiment, a gyratory crusher comprises: a bowl shaped as a cone and having a wider opening approaching a top portion of the crusher, and wherein the bowl has an inner shell, which is backed by a concrete outer shell; a head assembly shaped as a cone, centrally located within the bowl and having a larger diameter at a bottom end portion of the bowl, so that the bowl and head assembly form a crushing volume which is larger at the top portion and smaller at the bottom end, with the head assembly including a central mainshaft which is located on an inclined axis within the bowl; and a cylindrical eccentric assembly including an eccentric central volume in which the main shaft is held so that, as the eccentric assembly rotates, the mainshaft gyrates, with the eccentric assembly rotating about a center hole within a central hub of the crusher. 
     In accordance with another exemplary embodiment, a method of making or retrofitting a gyratory crusher comprises: forming a concrete outer shell shaped as a cone and having a wider opening approaching a top portion of the outer concrete shell; and lining the concrete outer shell with a fabricated form. 
     Other details, objects, and advantages of the invention will become apparent as the following description of certain present preferred embodiments thereof and certain present preferred methods of practicing the same proceeds. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Present preferred embodiments of crushing devices, such as gyratory crushers, crushing circuits or cone crushers, and methods of making such devices are shown in the accompanying drawings in which: 
         FIG. 1  is a cross sectional view of a concrete gyratory crusher in accordance with an exemplary embodiment. 
         FIG. 2  is a flow chart showing a method of making or retrofitting a gyratory crusher in accordance with an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION OF PRESENT PREFERRED EMBODIMENTS 
     In accordance with an exemplary embodiment, a gyratory crusher  100  includes a bowl  110  comprised of an inner shell  111 , which is backed by a concrete shell  114 . In accordance with an exemplary embodiment, the concrete shell  114  is lined with a plurality of fabricated forms  112 . In accordance with an exemplary embodiment, the plurality of fabricated forms are a plurality of thin metal plates or shells  116 . It can be appreciated that by replacing the outer metal shell or casting with a plurality of thin metal plates (or shells)  116  and an outer concrete shell  114 , the bowl  110  of the gyratory shell is easier to manufacture based on the use of concrete or other materials. In addition, the bowl  110  can be manufactured at a lower cost and with reduced lead times. In addition, by using a concrete shell  114  lined with thin metal plates (or shells)  116 , the size of the gyratory crusher  110  is also no longer limited to the largest castable shell. 
       FIG. 1  is a cross sectional view of a preferred embodiment of concrete gyratory crusher  100  in accordance with an exemplary embodiment. As shown in  FIG. 1 , the concrete gyrator crusher  100  includes bowl or shell  110  shaped as a cone with its wider opening at the top, and head assembly  120  which is located on the axis of bowl  110 . The head assembly  120  is shaped as a cone and has its larger diameter at the lower end of bowl  110  so that together the bowl  110  and the head assembly  120  form crushing volume, which is larger at the top and smaller at the lower end. This configuration permits larger material to be fed into the top of crusher  100 , and which falls to the bottom of bowl  110  as it is crushed into smaller pieces and exits the crusher  100 . Typically, both the bowl  110  and the head assembly  120  have replaceable working surfaces. The bowl  110  has a liner (not shown), called a “concave” in the industry, and head assembly  120  has a liner (not shown) referred to as a “mantle”. 
     In accordance with an exemplary embodiment, the head assembly  120  is located adjacent to an eccentric assembly  130  which is rotated by a ring gear  124 . The eccentric assembly  130 , within which the lower portion of a mainshaft  134  is held, imparts to the head assembly  120  an eccentric motion, essentially a gyration, for the crusher  100  to function. The motion is imparted to the head assembly  120  by the eccentric assembly  130  that has an eccentric center volume, although the eccentric assembly  130  is itself cylindrical and mounted in a centered cylindrical support hole within a center hub. The eccentric assembly  130  along with annular shell  132 , are part of the bottom support structure of crusher  100 . The eccentric assembly  130  rotates about a center hole and, as eccentric assembly  130  rotates, its eccentric center volume moves the bottom end of mainshaft in an eccentric path imparting the gyratory motion to head assembly  120 . 
     The mainshaft  134  of the head assembly  120  fits into and is attached to the eccentric assembly  130 , and, at the top of the crusher  100 , the mainshaft  134  is located by bushings or bearings within a spider (or spider device)  140 . The spider (or spider device)  140  is the upper support member of the crusher  100 . The eccentric assembly  130  and the mainshaft  134  are supported from below the eccentric assembly  130  by a hydraulic support assembly  132 . The hydraulic support assembly  132  is typically comprised of a cylindrical support and a piston assembly. 
     In accordance with an exemplary embodiment as shown in  FIG. 1 , the bowl (or shell)  110  is comprised of a plurality of prefabricated (or fabricated) forms  112 , which are preferably in the form of a thin metal shells or plates  116 . The plurality of prefabricated forms  112  are backed with a concrete outer shell  114  for support. The fabricated forms  112  also can include an anchor or other means of attaching to the fabricated forms  112  to the concrete outer shell  114 . In addition, the fabricated forms  112  are preferably lined with wear resistant castings (or concaves)  118 . 
     In accordance with an exemplary embodiment, the thin metal shell or plates  116  are preferably rolled metal plates. However, it can be appreciated that other types of metal shells or plates  116  and/or metal working can be used. The thin metal plates and/or shells  116  preferably have a thickness of approximately 0.01 to 6 inches. It can be appreciated that one of the benefits of a concrete outer shell or bowl  110  is that the manufacturing of the bowl  110  including the concrete outer shell  112  and the thin metal shell or plates  116  is not limited to large cast facilities, but can be performed local to the installation. In addition, by providing an outer concrete shell  114 , the concrete reduces the noise level of the crusher during operation. 
     In accordance with another exemplary embodiment, the concrete outer shell  114  can be manufactured in a plurality of sub-assemblies or parts, which are assembled on location using a grout or other material to hold the plurality of sub-assemblies together to form a concrete bowl  110 . It can be appreciated that the concrete outer shell  114  is designed to allow access to the maintenance points of the bottom shell or portion of the crusher  110 , including the head assembly  120  and the eccentric assembly  130 . 
     In accordance with an exemplary embodiment, the concrete outer shell  114  can include an optional grout material, which provides additional support to the concrete gyratory crusher  100 . In accordance with an exemplary embodiment, an intermediate epoxy and/or backing material can also be injected or other wise applied to the thin metal plates or shells  116  to enhance and/or ensure good adhesion or contact between the thin metal plates or shells  112  and the supporting material (i.e., concrete outer shell  114 ). The epoxy and/or backing material can also be used to fill any voids that may be present in the supporting material (i.e., concrete outer shell  114 ). 
     The bowl  110  also preferably includes a plurality of reinforcement bars  150 , which are embedded within the concrete shell  114  to provide added support to the concrete shell  114 . The plurality of reinforcement bars  150  are preferably embedded with the concrete shell  114  along an inner edge or surface of the concrete outer shell  114 , and extend from the top portion (or upper portion) to a lower portion (or bottom portion) of the bowl  110 . 
     In addition, the top portion of the bowl  110  also includes a spider pocket and a top metal flange  152 , and which is embedded on the top end of the crusher  100  with provisions to fix the spider (or spider device)  140 . The head assembly  120  also includes a bottom shell  160 , which is embedded directly into the concrete outer shell  114 . In accordance with an exemplary embodiment, the bottom shell  160  is preferably a two arm bottom shell  160 , which is mount and/or embedded within the concrete shell  114  to provide additional reinforcement to the concrete gyratory crusher  100 . 
     In accordance with an exemplary embodiment, a method of making or retrofitting a gyratory crusher  200  comprises the steps of forming a concrete outer shell shaped as a cone having a wider opening approaching a top portion of the outer concrete shell  210 , and lining the concrete outer shell with a fabricated form  220 . The method also includes lining the fabricated forms with a wear resistant casting  230 . A head assembly is centrally located within the lined outer concrete shell  240 . 
     It should be understood that a customer may be provided with a gyratory crusher such as a cone crusher in one sale. Thereafter, a customer may be told of a method of retrofitting that cone crusher or other gyratory crusher to form, a cone crusher that includes a bowl comprised of an inner shell or lining and an outer concrete shell member. Such a retrofitted cone crusher or other gyratory crusher may be similar to the embodiment shown in  FIG. 1 . The inner shell (or lining) and/or outer concrete shell member may be provided by a supplier or may be purchased from the vendor that previously sold the customer the gyratory crusher. It is contemplated that the vendor or the customer may perform the retrofitting. 
     It is to be understood that the form of this invention as shown is merely a preferred embodiment. Various changes may be made in the function and arrangement of parts; equivalent means may be substituted for those illustrated and described; and certain features may be used independently from others without departing from the spirit and scope of the invention as defined in the following claims.