Abstract:
A one piece ground stake for securing drain, waste or vent pipe relative to the ground comprises a wire rod bent to form a hook having a ground engaging shank, a pipe engaging bend or cradle and a connecting leg connected between the pipe engaging bend and the shank by upper and lower connecting bends. The upper connecting bend extends above the lower connecting bend and is adapted to be struck by a hammer or the like to drive a lower end of the shank into the ground. The stake is driven into the ground until the cradle abuts against an upper surface of a pipe positioned on a bed of gravel, sand or the ground at a selected grade and position.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to ground stakes for use in securing drain pipe and the like to the ground. 
   When laying drain or waste pipe in construction projects it is important that the pipe is maintained at a proper grade or slope to permit proper draining. Once the pipe is laid in position, typically on a gravel bed, ground stakes are then used to secure the pipe in position and to prevent the pipe from floating upward or moving from side to side as additional gravel and concrete are poured around and over the pipe. If the pipe is allowed to float the desired grade may not be maintained and if the pipe is allowed to move from side to side, the relative position of inlets and outlets or stub ups may change. 
   Examples of existing ground stakes are the TOMAHAWK™ DWV Ground Stakes sold by Sioux Chief Manufacturing Company, Inc., as seen on page 17 of its 2001 Catalog. The TOMAHAWK™ ground stakes are of two piece construction comprising a hook shaped head which is attached to a straight length of rebar or the like. One version of the TOMAHAWK™ ground stake utilizes a metal head which is welded to the metal rebar and an alternative embodiment utilizes a molded plastic head having a hole for receiving one end of a rebar stake. The plastic head is held on the rebar by frictional engagement. 
   Although the existing TOMAHAWK™ ground stakes work well for their intended purpose, the two piece construction adds to the expense in manufacturing and assembling the items. There remains a need for a ground stake that is relatively inexpensive to manufacture and easy to use in securing drain, waste or vent pipes in position during the construction process. 
   SUMMARY OF THE INVENTION 
   The present invention comprises a ground stake for use in securing a pipe, such as drain, waste or vent pipe, in position relative to the ground to prevent the pipe from moving as gravel, concrete or other materials are poured over and around the pipe during construction. Although the invention is described herein primarily with reference to drain pipe, it is to be understood that the ground stake is also adapted for use with waste and vent pipes. 
   The ground stake comprises a hook having a shank, a pipe engaging bend or cradle and a connecting leg connected between the pipe engaging bend and the shank by upper and lower connecting bends. The upper connecting bend extends above the lower connecting bend and is adapted to be struck by a hammer or the like to drive the lower end of the shank into the ground. The stake is driven into the ground until the cradle abuts against an upper surface of a pipe laying on a bed of gravel, sand or the ground. 
   Alternatively, the ground stake can be used to support a pipe above the ground. The shank is driven into the ground until the top of the hook is positioned at the desired height to support a pipe. The pipe is then positioned to rest on top of the ground stake, cradled between the pipe engaging bend and the upper connecting bend, connecting the connecting leg to the shank. The pipe is secured to the ground stake using string, a band, a cable tie or the like threaded around the connecting bend, around the upper curved surface of the pipe and then around the pipe engaging bend of the hook. 
   The hook is preferably formed from a metal rod with the upper connecting bend bent so that the connecting leg extends approximately parallel to the shank or towards parallel alignment with the shank and a gap is formed between the connecting leg and the shank. The gap between the connecting leg and the shank measured just below the connecting bend is preferably no wider than one and a half times as wide as the thickness of the shank. The gap is typically slightly narrower near the upper connecting bend than it is near the second connecting bend. The desired gap is obtained in forming the connecting bend by bending the rod around a bending tool having a radius that is approximately the same and preferably no more than one and a half times the radius of the rod. The resulting radius of the connecting bend is therefore, approximately the same dimension as and preferably no more than one and one half times the radius of the rod itself. 
   Gripping projections are formed on the shank near a lower end thereof. The gripping projections extend outward from the outer surface of the shank and are adapted to help hold the stake in the ground and provide some resistance to movement of the stake upward out of the ground. 
   The objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a fragmentary perspective view showing a pair of ground stakes driven through a gravel bed and into the ground (not shown) and securing a drain pipe in position on the gravel bed. 
       FIG. 2  is an enlarged and fragmentary cross-sectional view showing one of the ground stakes driven into the ground and securing the drain pipe in position on the bed of gravel in a manner similar to that shown in  FIG. 3 , with an additional layer of gravel and then a layer of concrete poured over the drain pipe. 
       FIGS. 3–7  are diagrammatic views showing the steps for bending a metal rod to form the ground stake and for forming ground gripping projections on a shank of the ground stake. 
       FIG. 8  is a side view of the ground stake as shown in  FIG. 4  showing outwardly extending projections formed thereon. 
       FIG. 9  is a fragmentary perspective view showing a pipe supported on a ground stake of the present invention. 
       FIG. 10  is a fragmentary and enlarged left side view of the pipe supported on the ground stake as shown in  FIG. 9 . 
       FIG. 11  is a fragmentary and enlarged front elevational view of the pipe supported on the ground stake as shown in  FIG. 9 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
   Referring to the drawings in more detail, the reference numeral  1  refers to a ground stake  1  of the present invention. In  FIG. 1 , a pair of ground stakes  1  are shown driven through a layer of gravel or a gravel bed  3  and into the ground  4  (see  FIG. 2 ) to secure a drain pipe  5  in position on the gravel bed  3  and relative to the ground  4 .  FIG. 2  shows one of the ground stakes  1  holding the drain pipe  5  in position relative to the ground  4  after an additional layer of gravel  7  and then a layer of concrete  8  have been poured over the drain pipe  5 , as is typical in the process of constructing foundations, parking lots and the like in which drain lines are run under a concrete slab. 
   The ground stakes  1  are preferably formed form round wire. Steel wire having a diameter of 0.375 inches is particularly well adapted for use in forming the ground stakes  1  of the present invention. The wire is bent to the desired shape using conventional wire bending techniques and processes. The basic steps of the wire bending process are shown diagrammatically in  FIGS. 3–7 . 
   Beginning with a predetermined length of wire rod  15 , see  FIG. 3 , distal end  14  of wire rod  15 , which was previously cut to the desired length, is bent back toward itself approximately one hundred and eighty degrees around a first wire bending tool or rod  16 , as shown diagrammatically in  FIG. 4 , to form a shank  17  an upper connecting bend  19  and a first transitional leg  21 . The first transitional leg  21  preferably extends in approximately parallel and spaced relation to the shank  17  such that a gap  23  is formed between the shank  17  and the first transitional leg  21 . The upper connecting bend  19  is shown as being rounded. However, it is to be understood that the upper connecting bend  19  as well as the other bends described herein could be of other configurations including relatively square or forming a relatively sharp angle. 
   In forming the upper connecting bend  19  in the manner described in association with  FIG. 3 , the radius of the first bending tool  16  is selected to be approximately equal to and preferably no more than approximately one and one half times greater than the radius of the wire rod  15  used to form the ground stake  1 . The radius of the resulting connecting bend  19  is approximately the same as the radius of the first bending tool  16  and as with the bending tool  16  is preferably approximately the same as or no more than one and a half times the radius of the rod  15 . 
   Referring again to the drawings and namely  FIG. 6 , the distal end  14  of the wire rod  15  is then bent upward approximately forty five degrees from horizontal, around a second wire bending tool or rod  25  as shown in  FIG. 6 , to form a connecting leg  26 , a lower connecting bend  28  and a second transitional leg  30 . The connecting leg  26  remains extending in approximately parallel, spaced relation to the shank with the gap  23  extending therebetween. The gap  23 , measured just below the upper connecting bend  19  is preferably approximately as wide as and no more than one and a half times as wide as the diameter of the wire rod  15  used to form the ground stake  1 . Although the connecting leg  26  preferably extends in parallel relation to the shank  17  forming the ground stake  1  such that the connecting leg  26  extends at a slight acute angle relative to the shank, preferably no more than approximately fifteen degrees is acceptable. 
   As generally shown in  FIG. 7 , the second transitional leg is then bent or curved downwardly around a third wire bending tool or rod  32  to form a pipe engaging bend  33  which may also be referred to as a pipe receiving bend or cradle  33 . The curvature or radius of the bend of the pipe receiving cradle  33  is selected to generally conform to or be slightly greater than the radius of the largest drain pipe with which the ground stake  1  is to be used. For example, in many applications, the diameter of the largest drain pipe  5  with which a ground stake  1  of the present invention is likely to be used is six and one half inches. Therefore, the curvature or radius of the pipe receiving cradle  33  for use with a six inch drain pipe  5  is at least approximately three and one quarter inches. 
   The wire rod  15  is bent so that the distal end  14  extends slightly below the lower most level of the lower connecting bend  26  to help keep a drain pipe  5  from moving sideways out from under the pipe receiving cradle  33 . In addition, the upper connecting bend  19  and upper portions of the connecting leg  26  and the shank  17  extend above the apex or uppermost point  37  of the pipe engaging bend  33 . 
   In an embodiment adapted for securing a six inch drain pipe  5  in position and formed from ⅜ inch diameter wire, the upper connecting bend  19  preferably extends above the apex  37  of the pipe engaging bend  33  by approximately one half an inch to one inch. The gap  23  of such a stake  1  taken along any line between the upper and lower connecting bends  19  and  28 , is preferably approximately the same width as the rod, three eighths of an inch, and preferably no wider one and one half times the width of the wire rod  15 , or {fraction (9/16)}ths of an inch for wire having a diameter of three eighths of an inch. 
   It is believed that forming the connecting leg  26  to be approximately parallel to the shank  17  makes the ground stake  1  easier to drive into the ground  4  by providing a clearly defined target to strike with a hammer, namely the upper connecting bend  19 . It is also believed that the downwardly extending parallel connecting leg  26  and shank  17  more efficiently direct the force of a striking hammer downward facilitating efforts to drive the stake  1  into the ground. 
   Referring to  FIG. 3 , outwardly extending, semi-circular projections or ground gripping projections  40  are formed on a lower portion of the shank  17  of each ground stake  1 . The projections  40  are formed by pinching or stamping opposed edges of the wire rod  15  between aligned sets of opposed pins  43  as shown diagrammatically in  FIG. 7 . It is foreseen that a wide variety of means or techniques could be utilized to texture the outer surface of the shank  17  to increase the frictional engagement between the ground  4  and the shank  17 . 
   A typical use of the ground stakes  1  is to secure a drain pipe  5  in position on a gravel bed  3  as generally shown in  FIGS. 1 and 2 . After a drain pipe  5  has been positioned on a gravel bed  4  above the ground  3  at the desired grade and location, the position of the drain pipe  5  is fixed by driving ground stakes  1  through the gravel bed  3  and into the ground  4  adjacent the drain pipe  5  until the pipe receiving cradle  33  is advanced into partially encircling engagement with an upper surface of the drain pipe  5 . The stakes  1  are driven into the ground  4  preferably by striking or otherwise applying a downwardly directed force on the upper connecting bend  19  of the stake  1 . The upper connecting bend  19  may also be referred to as the strike zone or area, the striking surface or the head of the stake  1 . 
   After the ground stakes  1  are driven through the gravel bed  3  and into the ground  4  securing the drain pipe  5  in position, the additional layer of gravel  7  and then a layer of concrete  8  are typically poured over the drain pipe  5 . Although the additional layer of gravel  7  is shown extending approximately even with or slightly above the upper connecting bend  19 , it is to be understood that variations of the thickness and relative depth of the layers will vary. 
   The ground stakes  1  hold the drain pipe  5  in place while the additional layer of gravel or any other material are poured over the drain pipe  5  and prevent the drain pipe  5  from “floating” or being pushed upward by gravel or other granular type material generally flowing under the sides of the drain pipe  5 . The ground stakes  1  also prevent the drain pipe  5  from moving sideways which can cause problems due to changes in the location of inlets and outlets to the drain line. 
   As shown in  FIGS. 9–11 , The ground stakes  1  of the present invention may also be used to support drain pipe  5  or the like on top of the ground stake  1 . Mounting the drain pipe  5  on top of the ground stakes  1  can facilitate the installation process by eliminating the need to lay or spread the gravel bed  3  at the desired grade. Instead the ground stakes  1  can be driven into the ground  4  until the top of the ground stake  1  is positioned at a selected height to support the ground stake  1  at the desired grade. The drain pipe  5  is then laid on top of the ground stake  1  so that the pipe  5  is supported between the upper curved surface of the pipe receiving cradle  33  and the upper or outer surface of the upper connecting bend  19 . The pipe  5  can be secured in place using string, wire, a cable tie  53  or the like. As shown in  FIGS. 9–11 , a cable tie  53  can be threaded through the gap  23  between the connecting leg  26  and shank  17 , and then both ends wrapped over and around the upper, outer surface of the pipe  5 , and then around the pipe receiving cradle  33  and secured together to secure the pipe to the ground stake  1 . It is foreseen that a wide variety of other ways for securing a pipe  5  to the ground stake  1  can be utilized. Once the pipe is secured in place at the desired slope or grade, gravel can then be poured around and beneath the pipe  5  to form the desired gravel bed to further support the pipe  5 , and then over the pipe  5  to the desired depth. 
   It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.