Magnetically fastenable magnetic wedge separator

Information

  • Patent Grant
  • 6708828
  • Patent Number
    6,708,828
  • Date Filed
    Thursday, April 18, 2002
    22 years ago
  • Date Issued
    Tuesday, March 23, 2004
    20 years ago
Abstract
A ferrous metal object separator is removably attachable to a conveyor which transports a moving stream of non-ferrous material (e.g. wood chips) in which some ferrous metal objects (e.g. screws, nuts, broken machinery parts, spikes, nails, steel filings, steel chips, etc.) may be commingled. The separator, which has a non-ferrous body, has an inclined surface extending upwardly from a leading edge to an abrupt trailing edge. A separating magnet embedded adjacent the separator's trailing edge magnetically retains the ferrous metal objects without substantially impeding transport of the non-ferrous material along the conveyor. A fastening magnet embedded in the separator removably magnetically fastens the separator on the conveyor.
Description




TECHNICAL FIELD




This invention relates to magnetic removal of ferrous metal objects from non-ferrous material.




BACKGROUND




Conveyors are used to transport various materials. As one example, a vibratory or “shaker” conveyor may transport non-ferrous material such as wood chips. The non-ferrous material may be commingled with ferrous metal objects (e.g. screws, nuts, broken machinery parts, spikes, nails, steel filings, steel chips, etc.), which if not separated from the non-ferrous material could be ingested into other processing machinery, potentially damaging the machinery. Screens provided in a shaker conveyor may not be adequate to remove such ferrous metal objects. This invention assists in removal of such ferrous metal objects.











BRIEF DESCRIPTION OF DRAWINGS





FIG. 1

is an oblique perspective view of a magnetically fastenable magnetic wedge separator in accordance with the invention.





FIG. 2

is a top plan view of the

FIG. 1

apparatus.





FIG. 3

is a cross-sectional side elevation view of the

FIG. 1

apparatus in operation on a shaker conveyor.











DESCRIPTION




Throughout the following description, specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.




The invention provides a wedge-shaped separator


10


having a leading edge


12


and a trailing edge


14


. One or more fastening magnets


16


are embedded within separator


10


to removably magnetically fasten separator


10


atop the ferrous metal surface


18


of a conveyor such as a shaker conveyor, without the need for structural modification or adaptation of the conveyor to receive or retain separator


10


. The body of separator


10


is preferably a non-ferrous material such as polyurethane formed in a wedge shape to provide an inclined surface


19


extending upwardly from leading edge


12


to trailing edge


14


. Protective caps


20


,


22


can be fitted over leading edge


12


and trailing edge


14


respectively. One or more separating magnets


24


are embedded within separator


10


, adjacent trailing edge


14


. Trailing edge cap


22


is made of a non-ferrous material to minimize interference with the magnetic field


32


of separating magnets


24


.




Conveyor surface


18


transports a moving stream of non-ferrous material


26


(e.g. wood chips) in the direction indicated by arrow


28


(i.e. from right to left as viewed in FIG.


3


). Non-ferrous material


26


may be commingled with some ferrous metal objects


30


(e.g. screws, nuts, broken machinery parts, spikes, nails, steel filings, steel chips, etc.).




Commingled non-ferrous material


26


and ferrous metal objects


30


are transported along conveyor surface


18


, initially encountering separator


10


's leading edge


12


which diverts commingled non-ferrous material


26


and ferrous metal objects


30


from conveyor surface


18


onto separator


10


's inclined surface


19


. Separator


10


is formed such that its width dimension “W” (

FIG. 2

) in only slightly smaller than the width of conveyor surface


18


, so that substantially all material transported along conveyor surface


18


will be diverted onto separator


10


's inclined surface


19


. The shaker conveyor's vibratory (shaking) action transports the diverted commingled non-ferrous material


26


and ferrous metal objects


30


across inclined surface


19


, toward and over trailing edge


14


which abruptly intersects conveyor surface


18


.




Commingled non-ferrous material


26


and ferrous metal objects


30


encounter the magnetic field


32


of separating magnets


24


as the commingled material and objects are transported over trailing edge


14


. Depending upon their size, substantially all ferrous metal objects


30


are magnetically attracted toward separating magnets


24


and magnetically retained on separator


10


near trailing edge


14


; without substantially impeding transport of non-ferrous material


26


along the conveyor. More particularly, non-ferrous material


26


is unaffected by separating magnets


24


, drops off trailing edge


14


onto conveyor surface


18


, and is transported along conveyor surface


18


away from separator


10


in the direction of arrow


28


for further processing (not shown). Periodically, at convenient times, any ferrous metal objects


30


magnetically retained on separator


10


can be removed, for example by scraping such objects off separator


10


with a non-metallic scraping tool (not shown).




Instead of using fastening magnets


16


to removably magnetically retain separator


10


atop conveyor surface


18


, metal backing plates can be embedded in separator


10


to facilitate welding, bolting, clamping or other attachment of separator


10


to the conveyor. This may however require structural modification or adaptation of the conveyor to receive or retain separator


10


. Besides avoiding conveyor modification or adaptation to receive or retain separator


10


, fastening magnets


16


allow rapid removal and replacement of separator


10


. Specifically, the tip of a pry bar—not shown—can be inserted into one of leading edge recesses


34


(or into another recess—not shown—in trailing edge


14


) and force can then be applied to the pry bar to break the magnetic bond between separator


10


and conveyor surface


18


. Other techniques known to persons skilled in the art, such as use of a jacking bolt—not shown—can be employed to break the magnetic bond between separator


10


and conveyor surface


18


. The capability to rapidly remove separator


10


from the conveyor also simplifies removal of ferrous metal objects


30


magnetically retained on separator


10


, after which separator


10


can be quickly returned to service on the conveyor. Fastening magnets


16


also allow separator


10


to be rapidly removed from one conveyor and placed in service on a different conveyor.




Fastening magnets


16


further allow separator


10


to be rapidly removed from one location on a particular conveyor and replaced in service at a different location on the same conveyor. This enables optimization of separator


10


's capability to remove ferrous metal objects


30


from non-ferrous material


26


, which may be affected by factors such as the particular type of non-ferrous material being conveyed; and, the size, volume or consistency of ferrous metal objects


30


typically commingled within non-ferrous material


26


.



Claims
  • 1. A ferrous metal object separator removably attachable to a ferrous metal surfaced conveyor for transporting a moving stream of commingled non-ferrous material and ferrous metal objects, said separator comprising:(a) an inclined surface extending upwardly from a leading edge to a trailing edge; (b) a separating magnet for magnetically retaining said ferrous metal objects without substantially impeding transport of said non-ferrous material along said conveyor; and (c) a fastening magnet for removably magnetically fastening said separator on said ferrous metal surface; said inclined surface and said separating magnet being stationary parts of said separator, said separator being movable with said conveyor.
  • 2. A separator as defined in claim 1, wherein said separating magnet is embedded in said separator adjacent said trailing edge.
  • 3. A separator as defined in claim 2, wherein said fastening magnet is embedded in said separator.
  • 4. A separator as defined in claim 2, wherein said separator is formed of a non-ferrous material and has a width slightly smaller than the width of said conveyor.
  • 5. A separator as defined in claim 1, wherein said fastening magnet is embedded in said separator.
  • 6. A separator as defined in claim 5, further comprising at least one pry bar recess formed in an outward edge of said separator.
  • 7. A separator as defined in claim 5, further comprising at least one pry bar recess formed in a lower outward edge of said separator.
  • 8. A separator as defined in claim 1, wherein said separator is formed of a non-ferrous material and has a width slightly smaller than the width of said conveyor.
  • 9. A separator as defined in claim 1, further comprising at least one pry bar recess formed in an outward edge of said separator.
  • 10. A separator as defined in claim 1, further comprising at least one pry bar recess formed in a lower outward edge of said separator.
  • 11. A method of removing ferrous metal objects from a moving stream of non-ferrous material commingled with said ferrous metal objects, said method comprising:(a) removably magnetically fastening said inclined surface in a fixed position relative to said moving stream; (b) diverting said moving stream across an inclined surface having an abrupt trailing edge; and (c) applying a magnetic field near said trailing edge to magnetically retain substantially all said ferrous metal objects near said trailing edge without substantially impeding movement of said non-ferrous material; while maintaining said inclined surface stationary relative to said separating magnet.
REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/341,216 filed Dec. 20, 2001.

US Referenced Citations (11)
Number Name Date Kind
393348 Atkins Nov 1888 A
719741 Burton Feb 1903 A
1576640 Ullrich Mar 1926 A
2517174 Bradley Aug 1950 A
2612268 Merwin Sep 1952 A
2654478 Stem Oct 1953 A
4229288 Akama Oct 1980 A
4235710 Sun Nov 1980 A
4565624 Martinez Jan 1986 A
5100538 Howes Mar 1992 A
6026966 Svoboda Feb 2000 A
Foreign Referenced Citations (2)
Number Date Country
2000117143 Apr 2000 JP
WO 9201617 Feb 1992 WO
Provisional Applications (1)
Number Date Country
60/341216 Dec 2001 US