Abstract:
A grading rake having a handle and a rake head, and having stiff but bendable, flexible polymer tines in the rake head, with the tines angled back toward the handle, and with the end of the tines truncated and parallel to the plane of the handle and rake head.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit under 35 U.S.C. §119(e) of prior U.S. Provisional Application No. 60/280,041 filed Mar. 30, 2001; all of which is hereby incorporated by reference. 

   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   This invention has been created without the sponsorship or funding of any federally sponsored research or development program. 
   BACKGROUND OF THE INVENTION 
   Grading rakes are typically employed by landscapers to spread topsoil evenly, generally prior to applying grass seed. The grading rake is used by pushing the head of the rake over the soil to level the soil and then by pulling the rake toward the user to pull or remove rocks, roots, twigs and the soil debris from the leveled soil. 
   Grading rakes presently in use comprise a handle and a traverse head section with spaced apart metal tines composed of cast aluminum or wood. 
   In such use, the tines wear down rapidly and the tines of the grading rake often break or bend when the tines strike rocks or other soil debris. 
   It is desirable to develop an improved grading rake which will be easily manufactured and which overcomes the disadvantages of prior art grading rakes. 
   BRIEF SUMMARY OF THE INVENTION 
   The invention relates to a grading rake having stiff but flexible polymeric tines which bend but do not break in normal use. 
   The invention comprises a grading rake which comprises an elongated handle and a traverse head with spaced apart tines secured to the head and a holder means to connect the one lower end of the handle to the head, such as a cast aluminum, solid triangular plate, or other holder means. The rake tines are formed of a stiff but flexible polymeric material, for example cylindrical nylon, and which tines have a length of about 2½–4 inches, a diameter of about ¼–½ inch, and which tines are uniformly spaced apart on the head from about ½–1½ inches. 
   The polymer material is solid, or may be a cellular material, but is stiff and capable of flexing at one end in use without breaking or permanently deforming, e.g., flexing ½–1 inch or more at the one end, while the other end is secured in the rake head. 
   The traverse rake head may be a generally solid cylindrical shape of wood with tine holes drilled therein and therethrough for the insertion of one end of the tines. The tines are inserted in the holes to the other side of the rake head and generally flush with the head surface and then fastened in place by screws, nails or adhesives, or a combination thereof. This arrangement provides for the tines to be securely held in the rake head (typical diameter of 1–2 inches) and provides that individual tines may be easily replaced, if required. 
   In a preferred embodiment the free raking end of the polymer tines are truncated, so that the surface end is a plane generally parallel to the area to be raked and to the plane of the rack handle and rake head. The tines are prepared from a solid cylindrical spool of nylon with one end cut square and the other cut to an angled flat surface, e.g., 30–60 degrees from the axis of the tine and parallel to the plane formed by the handle and rake head. 
   The lower end of the handle is secured to the rake head by a securing means. In one embodiment, the securing means comprises a cast aluminum, solid triangular piece with an outer arcuate shape adapted to fit about the rake head and to be fastened in position. The rear of the securing means comprises an extended hollow piece of square cross-section adapted to receive and hold the lower or forward end of the handle securely in place with the handle end fastened therein. This arrangement, unlike the prior art use of individual extended supports, provides a solid support for the rake head. The handle is secured to the rake head so that the handle is perpendicular to the axis of the rake head. 
   The invention will be described for the purpose of illustration only in connection with certain illustrated embodiments. However, it is recognized that various changes, modifications, additions, and improvements may be made in the illustrative embodiments without departing from the spirit or scope of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The character of the invention, however, may be best understood by reference to one of its structural forms, as illustrated by the accompanying drawings in which: 
       FIG. 1  is a perspective view of the grading rake of the invention; 
       FIG. 2  is an enlarged front plan view of the rake head of  FIG. 1 ; 
       FIG. 3  is a sectional view along lines  3 — 3  of  FIG. 2 ; and 
       FIG. 4  is a further enlarged front plan view of the rake head of  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The drawings, and particularly  FIG. 1 , illustrate a grading rake  10  embodying the invention and adapted to grade soil  30 . The rake  10  has an elongated wooden handle  12  with one end secured in a cast aluminum, solid triangular holder  22 . The holder  22  has a front arcuate curve  24 . The handle holder  22  secures the lower end of the handle  12  by containing the lower end in a back handle holder cavity  32 . The arcuate curve  24  of the holder  22  surrounds a cylindrical wooden rake head  14  and is fastened to the cylindrical wooden rake head  14  with one or more fasteners  26 . 
   The traverse rake head  14  carries a plurality of solid nylon tines  16 , which flex and wear evenly and are uniformly spaced apart and extending downwardly and rearwardly, in the general direction of the handle, from the rake head. The upper end of each tine  16  is positioned in a hole  28  in the rake head  14 , and releasably secured in the rake head  14  by fastener nails  20 . 
   The tines may be formed of nylon or other tough and flexible material. the material may be reinforced and/or modified with fiberglass, carbon fiber, abrasion resistant fillers, or similar compositing materials. 
   The free end of each tine is truncated to 45° from the axis of the tine, while the handle through the securing holder has a similar angle to the tines. The truncated surface of each tine is parallel to the plane formed by the handle  12  and the rake head  14 . 
   In particular,  FIG. 2  shows the front view of the rake head, while  FIG. 3  illustrates, in a cross-sectional view through the rake head  14 , how the individual tines  16  are secured in the holes  28  in the rake head  14 . Removal of fastener nails  26  permits individual tines  16  to be easily withdrawn, replaced, and refastened in position. 
   The grading rake of the invention as described provides for a rake in which the tines are not broken or bent in use, provides easy replacement of the tines, and a sturdy connection holder to secure the handle and rake head. 
   The ideal angle between the handle and plane of the tines is about 45 degrees, with 30 to 60 degrees being desired, and with 40 to 50 degrees being preferred. The ideal angle between the free end surface of the tines and the plane of the handle and the rake head is about zero, with −10 to +10 degrees being desired, and with −5 to +5 degrees being preferred. The ideal angle between the free end surface of the tines and axis of the tines is about 45 degrees, with 30 to 60 degrees being desired, and with 40 to 50 degrees being preferred. 
   The preferred use of the grading rake is the grading of particulate matter containing certain undesirable relatively large particles, such as soil which contains rocks and sticks. In essence, the user pushes the rake head forward across to particulate matter to smooth the surface of the matter, the backwardly directed tines and their truncated horizontal free end surface ride on top of the material, thereby spreading the material and unifying and smoothing it upper surface. Then, the user draws the rake head back so that the rear edge of the free end of the rearward directed tines engages large particles in the material, lift the large particle up onto the tines and elevate and separate the large particles from the material. The large particles can then be segregated from the particulate matter. In this way, the upper surface of the material can be graded, smoothed, and given the desired uniform fine texture.