Abstract:
The present invention embodies an insert for attachment to a hammer of a size reducing machine for use in size reducing waste material, comprising a body with a centrally located mounting hole to allow for attachment of the insert to the hammer. The body also includes a bullet shaped tip distally located in relation to the body, wherein the tip can size reduce waste material on impact.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a hammer insert with a bullet shaped tip. In particular, to a hammer insert for securement to a hammer of a size reducing machine, with a distally located bullet tip.x 
     Prior art asphalt and concrete stripping machines have used bullet shaped inserts or tips for size reduction. This design typically incorporates a pointed cone or partially specially shaped tip joined to a round threaded end for removable attachment to the stripping machine. The tip presents a sharp pointed end that impacts the surface of the material being size reduced. The tip requires removal and replacement when worn from repeated impact. This requires frequently stopping operation of the size reducing machine to complete the maintenance work. 
     Additionally, the conventional bullet tip design provides little contact area for mounting the insert to a hammer. This makes the prior art bullet tip inserts susceptible to loosening during operation. A loose insert can dislodge during operation causing damage to the machine, and this represents a dangerous operating condition. 
     Furthermore, the prior art bullet tip design cannot be used with other types of standard size reducing machines, like tub grinders, rotary hammermills, and other machines that use the traditional rotatable bolt-on insert design. The difference between the bullet tip and bolt-on inserts requires the use of different methods of attachment, which make the inserts non-interchangeable. 
     Accordingly, a need exists for a bullet tip insert that allows for use with a wider range of size reducing machines. 
     SUMMARY OF THE INVENTION 
     An object of the present invention comprises providing an insert for attachment to a hammer of a size reducing machine for use in size reducing waste material. 
     These and other objects of the present invention will become apparent to those skilled in the art upon reference to the following specification, drawings, and claims. 
     The present invention intends to overcome the difficulties encountered heretofore. To that end, the present invention embodies an insert for attachment to a hammer of a size reducing machine for use in size reducing waste material, comprising a body with a centrally located mounting hole to allow for attachment of the insert to the hammer. The body also includes a bullet shaped tip distally located in relation to the body, wherein the tip can size reduce waste material on impact. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a prior art bullet tip insert. 
     FIG. 2 is a side view of a prior art bolt-on insert. 
     FIG. 3 a  is a side view of an insert. 
     FIG. 3 b  is an end view of the insert of FIG. 3 a.    
     FIG. 3 c  is top view of the insert of FIG. 3 a.    
     FIG. 3 d  is a top view of the insert of FIG. 3 a , turned 180° from the top view shown in FIG. 3 c.    
     FIG. 4 a  is an end view of an insert. 
     FIG. 4 b  is a top view of the insert of FIG. 4 a  with the tips removed. 
     FIG. 4 c  is a side view of the insert of FIG. 4 a.    
     FIG. 4 d  is a side view of a bullet tip. 
     FIG. 5 a  is an end view of an insert. 
     FIG. 5 b  is a top view of the insert of FIG. 5 a  with the tips removed. 
     FIG. 5 c  is an end view of the insert of FIG. 5 a  with the tips removed. 
     FIG. 5 d  is a side view of the insert of FIG. 5 a  with the tips removed. 
     FIG. 5 e  is an end view of the insert of FIG. 5 a , rotated 90° from the end view shown in FIG. 5 c  with the tips removed. 
     FIG. 5 f  is a side view of a bullet tip. 
     FIG. 6 a  is a top view of an insert with the tips removed. 
     FIG. 6 b  is an end view of the insert of FIG. 6 a  with the tips removed. 
     FIG. 6 c  is a side view of the insert of FIG. 6 a  with the tips removed. 
     FIG. 6 d  is a side view of a bullet tip. 
     FIG. 7 a  is a top view of an insert with the tips removed. 
     FIG. 7 b  is a side view of the insert of FIG. 7 a  with the tips included. 
     FIG. 7 c  is an end view of the insert of FIG. 7 a.    
     FIG. 8 a  is a top view of an insert with the tips removed. 
     FIG. 8 b  is a side view of the insert of FIG. 8 a  with the tips included. 
     FIG. 8 c  is an end view of the insert of FIG. 8 a.   
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the Figures, FIG. 1 shows a prior art bullet tip insert  10 . The insert  10  includes a body  12  with a bullet tip  14  at one end and threads  16  at the other end. The bullet tip  14  is typically made of solid carbide. The threads  16  allow for releasable securement to the body of a hammer (not shown) of a size reducing machine (not shown). The prior art bullet tip insert  10 , as mentioned previously, is designed for use with asphalt and concrete stripping machines. And, the insert  10  adapts for use with fixed or swing hammer machines. The body  12  of the insert  10  provides little surface area for attachment, and as a result is subject coming lose or detaching during operation. 
     FIG. 2 shows a prior art standard two-bolt replaceable insert  20 . The insert  20  includes a generally rectangular body  22  and one or more tips  24 . The upper portion of the body  22  of the insert  20  typically includes a wear resistance coating (FIG.  2  - shaded region), like tungsten carbide. The wear resistance coating provides protection for the surfaces of the insert  20  that come into direct contact with debris during operation. The insert  20  also includes one or more bolt holes  26  to allow for attachment of the insert  20  to a hammer. As can be seen the insert  20  and the insert  10  embody different, and incompatible, designs for hammer attachment. 
     FIGS. 3 a-d  shows an insert  30  of the present invention. The insert  30  includes a body  32  similar in design and shape to the body  22  of the prior art insert  20 . The insert  30  also includes one or more bullet tips  34  similar in design and shape to the bullet tip  12  of prior art insert  10 . The insert  30  utilizes bolt holes  36  to releasably attach the insert  30  to a hammer. The body  32  of the insert  30  allows for wide variety of arrangements for the placement of the bullet tips  34 . In each case the bullet tips  34  are distally located toward at least one edge of the body  32  of the insert  30 . In FIG. 3, the bullet tips  34  are located distally and off center with respect to the body  32  of the insert  30 . 
     FIG. 4 c  shows an insert  40  with a body  42  and two bullet tips  44 . The insert  40  also includes tip holes  46  (see FIG. 4 b ), to allow for insertion of bullet tips  44  (see FIG. 4 d ).The bullet tips  44  are distally located and centered with respect to the body  42  of the insert  40 . In the preferred embodiment of the invention the bullet tips  44  are silver soldered or welded in place within the tip holes  46 . 
     FIG.  5  and FIG. 6 show additionally options for location of the bullet tips. In particular, FIGS. 5 a-f  shows an insert  50  with a body  52  and three distally located tips holes  56  for use with three bullet tips  54 . One end of the body  52  includes two bullet tips  54 , while the other end of the body  52  includes one centrally located tip  54 . FIGS. 6 a-d , shows an insert  60  with a body  62  and four distally located tip holes  66  to allow for the use of four bullet tips  64 . 
     FIGS. 7 a-c  show an insert  70  that includes a body  72 . The insert  70  also includes distally, and centrally located tip holes  74  for insertion of bullet tips  75  (see FIG. 7 b ), inserted in the manner described above. The insert  70  also include a bolt hole  76  to allow for the insertion of a bolt (not shown) to mount the insert  70  to a hammer (not shown). The insert  70  differs from the inserts shown above in that the bolt hole  76  is threaded to receive the opposite end of the bolt. For example, FIG. 3 a  shows an insert  30  with a bolt hole  36  that is enlarged to receive the hexagonal head of a bolt (not shown). The bolt hole  76  or the inert  70  does not receive the bolt head, but the opposite end of the bolt. Centrally located tip holes  74  may not leave sufficient room to permit a bolt hole wide enough to accommodate the recess for the bolt head, without compromising the structural integrity of the insert  70 . The solution comprises inserting the bolt in the opposite direction and using a threaded bolt hole  76  to capture the bolt. This eliminates the need for a nut, and allows for the smallest possible bolt hole  76 . 
     FIGS. 8 a-c  show an insert  80  that includes a body  82 . The insert  80  also includes distally, and centrally located tip-holes  84  for insertion of bullet tips  85  (see FIG. 8 b ), in the manner described above. The insert  80  also includes two threaded bolt holes  86  to allow for a bolt (not shown) to mount the insert  80  to a hammer (not shown). The insert  80  differs from the insert  70  in that it includes two bolt holes  86 , rather than one bolt hole  76 . However, the bolt affixes in the manner described for the insert  70 . 
     The present invention combines the advantages of the bullet tip and traditional bolt-on inserts. The present invention allows for use of both type of inserts with one hammer design, which allows for quick and flexible configuration of a size reducing machine for a much wider variety of applications. For example, the size reducing machine can be converted to, or from, a bullet tip insert without changing the hammers. Furthermore, the design of the present invention provides two or more bullet tips on a single insert. This allows for rotating the insert after one of the tips is worn, thereby essentially doubling the useful life of the insert. Also, the present invention provides for a more secure means of attachment, the bullet tip inserts to a hammer, than prior art designs. Use of the bolt-on insert body greatly increases the amount of surface area used for securing the insert to the hammer. This is especially true in consideration of the fact that the insert of the present invention can take advantage of the Saddle-Back Hammer Tip design disclosed in U.S. patent application Ser. No. 09/326,209 filed on Jun. 4, 1999, incorporated herein by reference. 
     The foregoing description and drawings comprise illustrative embodiments of the present inventions. The foregoing embodiments and the methods described herein may vary based on the ability, experience, and preference of those skilled in the art. Merely listing the steps of the method in a certain order does not constitute any limitation on the order of the steps of the method. The foregoing description and drawings merely explain and illustrate the invention, and the invention is not limited thereto, except insofar as the claims are so limited. Those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.