Production plus hammer with protective pocket

Information

  • Patent Grant
  • 6419173
  • Patent Number
    6,419,173
  • Date Filed
    Tuesday, July 27, 1999
    25 years ago
  • Date Issued
    Tuesday, July 16, 2002
    22 years ago
Abstract
A hammer comprising a hammer body. The hammer body comprises a rotor forming portion with a trailing and a leading edge and is capable of securement to a rotor, a tip support section capable of extending into a debris path, and a production pocket extending from the leading edge of the rotor portion also capable of extending into the debris path. The hammer also comprises a hammer tip secured to the tip section of the hammer body and at least partially shielded from the debris path by the production pocket of the hammer body.
Description




BACKGROUND OF THE INVENTION




The invention relates generally to a hammer attachable to a hammermill, or a tub grinder, or the like. More specifically, the invention relates to a hammer with the hammer body formed to extend the useful life of a rotatable hammer tip.




Impact crushers, like rotary hammermills or tub grinders, or the like, of the type contemplated herein, are widely used to size reduce objects into smaller fragments through rotation of a motor driven rotor. These devices typically include a plurality of hammers attached to the rotor, which strike the debris thereby causing the size reduction. The prior art describes the use of two piece hammers that comprise a hammer body and a rotatable hammer tip (see U.S. Pat. No. 5,285,974). Utilizing the rotatable hammer tip comprises a quick and convenient means for replacing an impacting working edge of the hammer tip. When the working edge of the hammer tip wears out, the hammer tip simply rotates through removal of securement bolts enabling operation to continue.




While the working edge of the hammer tip receives the brunt of the impacting force, the non-working edge of the hammer tip often comes into substantial residual contact with the debris. This can reduce the effective life of the non-working edge by anywhere from 25 to 50 percent or more. In other words, residual deflected contact with debris by the non-working edge of the hammer tip unnecessarily exposes the non-working edge of the rotatable hammer tip to wear and tear, and shortens the life of the non-working edge after rotating the rotatable hammer tip. This essentially reduces the life of a rotatable hammer tip, increases the cost of operation, and increases down time by requiring more frequent replacement of the rotatable hammer tips. Additionally, residual impact can also damage the securement bolts that attach the rotatable hammer tip to the hammer body.




Accordingly, for the foregoing reasons, a need exists for a hammer that utilizes a rotatable hammer tip that reduces premature wear and tear on the non-working edge of the hammer tip.




SUMMARY OF THE INVENTION




An object of the present invention comprises extending the useful life of a hammer tip by protecting a portion of the hammer tip from a debris path.




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 involves a hammer comprising a hammer body. The hammer body comprises a rotor forming portion with a trailing and a leading edge and is capable of securement to a rotor, a tip support section capable of extending into a debris path, and a production pocket extending from the leading edge of the rotor portion also capable of extending into the debris path. The hammer also comprises a hammer tip secured to the tip section of the hammer body and at least partially shielded from the debris path by the production pocket of the hammer body.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1



a


is a front elevation view of a prior art hammer body.





FIG. 1



b


is a side elevation view of the prior art hammer body of

FIG. 1



a.







FIG. 2

is a top plan view of a prior art impact crusher.





FIG. 3



a


is a front elevation view of a hammer.





FIG. 3



b


is a side elevation view of the hammer of

FIG. 3



a.







FIG. 4

is a top plan view of a prior art impact crusher.











DETAILED DESCRIPTION OF THE INVENTION




In the drawings,

FIGS. 1-2

show an example of a prior art hammer


10


and a prior art impact crusher


8


. The impact crusher


8


consists of a motor driven rotor


36


, which drives a plurality of hammers


10


. The hammer


10


in turn comprises a hammer body


12


with a rotor forming portion


14


capable of securement to the rotor


36


. Additionally, the rotor forming portion


14


comprises a leading edge


16


, and a trailing edge


18


. The hammer body


12


of the hammer


10


configures in such a manner that the leading edge


16


of the rotor forming portion


14


orients in the direction of the axis rotation


34


of the rotor


36


. The rotatable hammer tip


24


contains a working edge


26


and a non-working edge


27


. The rotatable hammer tip


24


secures to the tip support portion


20


of the hammer body


12


through securement bolts


30


.





FIG. 2

clearly shows that during operation the rotation of the rotor


36


exposes both the working edge


26


and the non-working edge


27


of the hammer tip


24


to contact with the debris. Furthermore, securement bolts


30


also lie directly in the debris path. Configured in this manner, the hammer


10


of the prior art impact crusher


8


suffers from the disadvantage of premature wear of the non-working edge


27


of the rotatable hammer tip


24


, and possible degradation and damage to the securement bolts


30


.





FIGS. 3-4

show the apparatus of the present invention. The present invention comprises an impact crusher


8


, comprising a motor driven rotor


36


and a plurality of hammers


10


securable to the rotor


36


. The hammer comprises a hammer body


12


, which further comprises a rotor forming portion


14


and a tip support portion


20


. The rotor forming portion


14


of the hammer body


12


further comprises a leading edge


16


and a trailing edge


18


. The rotor forming portion


14


of the hammer body


12


, however, differs substantially from the prior art in that the leading edge


16


of the rotor forming portion


14


contains a production pocket


22


. The production pocket


22


extends upward from the leading edge


16


into the debris path a distance great enough to protect a portion of the rotatable hammer tip


24


. In this manner, the rotatable hammer tip


24


contains a working edge


26


, fully exposed to the debris path and a protected edge


28


. The protected edge


28


of the rotatable hammer tip


24


rests behind the production pocket


22


, and out of the debris path.




A further advantage of the production pocket


22


comes from the ability of the production pocket


22


to control the flow of debris. Because the production pocket


22


extends into the debris path it not only protects the non-working or protected edge


28


of the hammer tip


24


, it re-directs debris toward the working edge


26


of the hammer tip


24


. Debris that encounters the production pocket


22


is direct upwards toward the working edge


26


. Of course, the further from the center of the rotor


36


that the debris impacts the hammer tip


24


the greater the force of impact. Thus, focusing debris toward the working edge


26


of the hammer tip


24


enhances the efficiency of the size reducing operation. In a similar manner, the production pocket


22


will re-direct debris toward the screen


9


and out of the machine. This also improves the efficiency of operation by reducing the operating time, and by reducing unnecessary wear on the working edge


26


of the hammer tip


24


by preventing impact of material already sufficiently size reduced.




Additionally,

FIG. 3



b


shows that the width of the production pocket


22


is substantially equal to a width of the rotatable hammer tip


24


. This allows the production pocket


22


to better deflect debris from the protected edge


28


of the rotatable hammer tip


24


. Furthermore, the production packet


22


also deflects debris thereby reducing the contact of debris with the securement bolts


30


. The production pocket


22


is coated with wear resistant coating, indicated in

FIGS. 3-4

by the shaded region, in order to protect the production pocket


22


upon contact with the debris. In the preferred embodiment of the invention the wear resistant coating of the production pocket


22


comprises tungsten carbide.




Configured in the manner shown, the hammer


10


substantially eliminates wear and tear on the protected edge


28


of the rotatable hammer tip


24


through adapting the hammer body


12


to include the production pocket


22


. The production pocket


22


by deflecting debris away from the protected edge


28


of the rotatable hammer tip


24


, and away from securement bolts


30


substantially increases the useful life of the rotatable hammer tip


24


. By increasing the useful life of the rotatable hammer tip


24


the production pocket


22


also reduces the cost, and down time associated with the operation of impact crushers


8


. Furthermore, by focusing debris toward the working edge


26


of the hammer tip


24


the production pocket


22


increases the efficiency of operation.




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. For example, those of ordinary skill in the art will realize that the production pocket


22


can be located on the rotor


36


or on the hammer


10


without departing from the scope of the intended invention.



Claims
  • 1. A size reducing machine utilizing a production pocket for use in increasing the efficiency of the operation of said size reducing machine, said machine comprising:a) a rotor; b) a hammer body comprising: i) a rotor forming portion capable of securement to said rotor; and ii) a tip support portion capable of extending into a debris path upon securement of said rotor portion of said hammer to said rotor; c) a rotatable hammer tip having a working edge secured to said tip support portion of said hammer body; and d) a production pocket extending far enough into said debris path to at least partially focus the flow of debris upward toward said working edge of said rotatable hammer tip.
  • 2. The invention in accordance with claim 1 wherein said production pocket is located on said rotor.
  • 3. The invention in accordance with claim 1 wherein said rotor forming portion of said hammer body further comprises a leading edge and a trailing edge and said production pocket is located on said leading edge.
  • 4. The invention in accordance with claim 1 wherein said working edge and said protected edge of said hammer tip are coated with a wear resistance coating.
  • 5. The invention in accordance with claim 4 wherein said wear resistance coating comprises tungsten carbide.
  • 6. The invention in accordance with claim 1 wherein said production pocket is coated with a wear resistance coating.
  • 7. The invention in accordance with claim 6 wherein said wear resistance coating comprises tungsten carbide.
  • 8. The invention in accordance with claim 1 wherein said hammer tip secures to said tip support portion of said hammer body with at least one securement bolt.
  • 9. The invention in accordance with claim 8 wherein said production pocket of said hammer body extends into said debris path enough to protect said securement bolt.
  • 10. The invention in accordance with claim 1 wherein said hammer tip is rotatable about an axis substantially tangent to an axis of rotation.
  • 11. The invention in accordance with claim 1 wherein a width of said production pocket is substantially equal to a width of said hammer tip.
US Referenced Citations (16)
Number Name Date Kind
1761083 Liggett Jun 1930 A
RE24806 Christiansen Apr 1960 E
2986347 Stevenson May 1961 A
3096035 Allen et al. Jul 1963 A
3680797 Covey Aug 1972 A
3929296 Stoeber Dec 1975 A
4136833 Knight Jan 1979 A
4161294 Lautenschlager et al. Jul 1979 A
4162770 Lewis Jul 1979 A
4915309 Schmidt Apr 1990 A
5022593 Stelk Jun 1991 A
5285974 Cesarini Feb 1994 A
5307719 MacLennan May 1994 A
5320292 Smith Jun 1994 A
5720440 Bonner et al. Feb 1998 A
5967436 Balvanz Oct 1999 A