Abstract:
A prefabricated step for insertion in a pair of spaced holes formed in a solid material includes an elongated step member having a harden core, a pair of outwardly projecting support members rigidly attached substantially at right angles thereto, each of the ends of said support members being adapted for insertion into the corresponding holes and having individual substantially arcuate and continuous resilient projections integrally molded thereon, and each of the projections has a slanted face inclined toward the step member and is deformable under pressure.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to supports and fasteners, especially anchoring devices having deformable projections or threads to fit smaller or tapered openings. 
         [0003]    2. Description of the Prior Art 
         [0004]    The prior art includes a substantial number of expansion anchors studs, concrete anchoring devices and other similar means providing a rigid device by means of which something may be attached to concrete. However, such devices are generally made from metal or at least a combination of metal and some other material such as rubber, wood or plastic and accordingly require some amount of preparatory work. 
         [0005]    U.S. Pat. No. 4,100,997 as shown in  FIG. 13  discloses an elongated step member having a pair of outwardly projecting support members integrally molded thereon and rigidly attached substantially at right angles thereto, each of the ends of said support members being tapered for insertion into the corresponding tapered holes and having individual substantially arcuate and continuous resilient projections integrally molded thereon from plastic material and the like. Each of the projections has a slanted face inclined toward the step member and including a marginal edge which is deformable under pressure so that when the end is driven into a respective opening of less distance than the overall distance between the marginal edges of the projections the projections are deformed and the step is held in place. The deformable members are circular and being progressively larger in diameter from the external terminal end toward the step whereby the respective ends may be aligned with a respective spaced hole and driven into a tapered hole to support the step and to seal the respective holes. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention relates to an improvement in the plastic coated, steel core reinforced manhole steps in particular, to the drive-in or hammer-in ends of the step construction. These improvements include the dual type wedges which provide greater pullout resistance when inserted into concrete. The inserts of the present invention provides significantly stronger steps and provides less flexible characteristics. Additionally, the present invention provides improvements regarding footing/thread slip resistance and quad reflectors for dark area identification/location. 
         [0007]    A carbon/forged steel core is formed of the sort which may be used as part of steps and has plastic, circular threads or projections which may be tapered and deformable so that when inserted in a drilled hole of slightly smaller diameter the projections will be deformed and bend under pressure to retain the fastener in place. 
         [0008]    The present concrete anchoring device may be used as step supports of the step and are easily hammered into a tapered opening in a concrete manhole or other concrete structure and will remain that way for a long period of time. 
         [0009]    The step has an elongated step member and a pair of projecting support members each being provided with projecting threads which deform when the ends are forced into a opening or an opening of slightly less diameter than the overall diameter of the projections. 
         [0010]    Other and further objects and advantages of the present invention will become apparent upon reading the following description of a preferred embodiment taken in conjunction with the accompanying drawings. 
     
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0011]    The invention may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which, like reference numerals identify like elements, and in which: 
           [0012]      FIG. 1  illustrates a top view of the step of the present invention; 
           [0013]      FIG. 2  illustrates a first side view of the step of the present invention; 
           [0014]      FIG. 3  illustrates a back view of the step of the present invention; 
           [0015]      FIG. 4  illustrates a second side view of the step of the present invention; 
           [0016]      FIG. 5  illustrates a side view of a first wedge ring of the present invention; 
           [0017]      FIG. 6  illustrates a front view of the first wedge ring of the present invention; 
           [0018]      FIG. 7  illustrates a back view of the first wedge ring of the present invention; 
           [0019]      FIG. 8  illustrates a side view of a second wedge ring of the present invention; 
           [0020]      FIG. 9  illustrates a front view of the second wedge ring of the present invention; 
           [0021]      FIG. 10  illustrates a back view of the second wedge ring of the present invention; 
           [0022]      FIG. 11  illustrates a side view of an end of a step support member; 
           [0023]      FIG. 12  illustrates a side view of the end of the step support member in concrete; 
           [0024]      FIG. 13  illustrates a perspective view of a step; 
       
    
    
     DESCRIPTION 
       [0025]      FIG. 1  illustrates a step designated generally by reference numeral  100  and which includes a core  102  which is shown as being substantially U shaped. The core  102  is coated with a plastic material such as polymer, polypropylene or other well known plastic material to protect the core  102  from the elements such as moisture. The core  102  may be formed from carbon/forged steel. The core  102  may be handened by either a cold process or heat treatment. With a cold process, the core  102  could be worked to the desired shape by hammering, pressing, rolling or stretching. With a heat treatment, the properties of the core  102  are changed by a series of temperature changes. The core  102  could be shaped to the round, square, I beam or any other suitable shape. The step  100  includes a step member  116  with an upper flat step surface  117  and respective opposed, step support members  118 ,  120  extending substantially 90° from the step member  116 . The core  102  extends substantially the entire length of the step member  106  and extends substantially the entire length of the step support members  118 ,  120 . Each end  119 ,  120  of the respective step support members  118 ,  120  is provided with a particular configuration which constitutes a device for retaining each step support member  118 ,  120  and the entire step  100  in place in concrete  125  by projections such as the first conical barbed retainer wedge ring  110  and the second conical barb retainer wedge ring  112  in a tapered hole or bore  126  shown in cross-section in  FIGS. 11 and 12 . The tapered opening or bore  126  is made by a drill or any other suitable means. Each end  119 ,  121  of the step support members  118 ,  120  is near identical in construction and is formed to include the plurality of staggered near identical, first conical barb retainer wedge rings  110  and second conical barb retainer wedge rings  120  or other suitable projections which may be the same size or which may be smaller or less in diameter from one another beginning with the endmost one leading toward the step member  116  or substantially the same diameter. Each first conical barb retainer wedge ring  110 ,  112  may be tapered in a direction towards the distal end of the step support member  118 ,  120  or not tapered. 
         [0026]      FIG. 2  illustrates a side view of the step support member  118  showing a flair step riser  108  positioned on opposing sides of the step  100  to prevent the shoe of the user of the step  100  from sliding off. The top surface of the flair step riser  108  may include a light reflector  106  to allow identification of the flair step riser  108  under low light conditions. The flair step riser  108  may include a inclined surface  109 .  FIG. 2  additionally illustrates the core  102  extending along the length of the step support member  118 . 
         [0027]      FIG. 3  illustrates a back view of the step  100  and shows the core  102  extending along the step member  116 .  FIG. 3  additionally illustrates the upward projecting protrusions  104  which may be cross (+) shape. These upper projecting protrusions  104  may allow a mating pattern formed on a shoe or boot for increased traction with the shoe or boot and may allow increased traction with a grooved sole. 
         [0028]      FIG. 4  illustrates the opposing step support member  120  which shows the core  102  extending along the length of the step support member  120 . 
         [0029]      FIG. 5  illustrates a side view of the first conical barb retainer wedge ring  110  which includes a continuous inclined surface  502  around the periphery of the first comical barb retainer wedge ring  110 . 
         [0030]      FIG. 6  illustrates a front view of the first conical barb retainer wedge ring  110 . 
         [0031]      FIG. 7  illustrates a back view of the first comical barb retainer wedge ring  110 . 
         [0032]      FIG. 8  illustrates a side view of the second conical barb retainer wedge ring  112  which includes a support section  802  which extends from the surface of the step support member  118 ,  120  to the inclined surface  804  of the second conical barb retainer wedge ring  112 . The support section  802  strengthens the second conical barb retainer wedge ring  112 . The second conical barb retainer wedge ring  112  is illustrated with a support section  802  spaced equally distant at approximately 90° with respect to another support section  802 . Fewer or additional support sections  802  are within the scope of the present invention. 
         [0033]      FIG. 9  illustrates that spaced between the support section  808  is discontinuous inclined surface  902 . 
         [0034]      FIG. 10  illustrates a back view of the second conical barb retainer wedge ring  112 . 
         [0035]    Accordingly, when the ends  119 ,  121  are aligned with the respective opening  126  in the concrete  125  and then hammered in place by a mallet or small sledge hammer the retaining wedge rings  110 ,  112  are caused to deform in the manner shown in  FIG. 3  and to be forced under pressure into the opening  26 . Thus, the resilient and deformable retaining wedge rings  110 ,  112  are under pressure holding the ends  119 , 121  rigidly in place in the respective opening  126 . 
         [0036]    A plurality of steps  100  are installed one above or below, as the case may be, the other by drilling respective holes  126  to accommodate the ends  119 , 121  driven into place. Steps  100  may be installed in this manner in a wall or concrete manhole without the use of expansion plugs or anchors. 
         [0037]    While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed.