Low-density particle sizing apparatus and method

Information

  • Patent Grant
  • 6679386
  • Patent Number
    6,679,386
  • Date Filed
    Wednesday, May 29, 2002
    23 years ago
  • Date Issued
    Tuesday, January 20, 2004
    22 years ago
  • Inventors
  • Original Assignees
  • Examiners
    • Walsh; Donald P.
    • Miller; Jonathan R
    Agents
    • Buckingham, Doolittle & Burroughs, LLP
    • Dureska; David P.
    • Kennedy; Edward T.
Abstract
An apparatus and method for sizing and separating particles of generally low-density materials includes a stand, a frame movably suspended on the stand by a plurality of suspension assemblies, and an elongated screen box mounted on the frame. The screen box receives material to be processed at an input end and includes openings at an output end for discharging processed material. The frame and screen box are disposed at an incline relative to a horizontal surface on which the stand rests, so that material travels downwardly in the screen box toward the output openings. A vibrator motor is mounted on the frame input end. The arrangement of the motor and suspensions results in imposition of a combination generally circular planar motion to the frame and screen box at the input end and a generally oblong linear reciprocating motion at the central portion and the output end of the apparatus.
Description




BACKGROUND OF THE INVENTION




The invention relates to screens for material processing and in particular to a screen apparatus and method for sizing and separating particles of materials by motorized vibration of one or more screens. More particularly, the invention is directed to a material processing apparatus and method which enables efficient sizing and separation of particles of low-density materials.




BACKGROUND ART




Material sizing equipment commonly is used in a variety of industrial processes including mineral processing of coal, iron ore, kaolin, bauxite, taconite, gold, phosphate, potash, silica sand, aggregate, and limestone. Such sizing equipment also is useful in chemical processing, pulp and paper processing, food processing, waste water and sewage treatment, refuse processing, soil processing, oil well drilling fluid cleaning, and in processing low-density materials such as fertilizer and plastic pellets. Equipment of the type intended for sizing and separating particles of a material usually includes a stand, a frame movably suspended on the stand, one or more elongated screens of varying sizes, depending on the processing application, mounted on the frame, and one or more motors mounted on the frame for vibrating the frame and attached screen. The material typically is deposited on one end of the vibrating screen, which sizes and separates particles of the material as it moves along the screen. The screen can be disposed horizontally and parallel to the surface on which the sizing equipment rests, or it can be inclined relative thereto with the material to be sized being deposited on the upper or lower end of the screen. In certain applications, the screen also serves to separate water from the material being sized.




Although such sizing equipment typically performs its intended functions well, it has become apparent in applications involving the sizing of low density dry materials having particles ranging in size from about 2 mesh (12 millimeters) to about 325 mesh (45 microns), that existing sizing equipment does not achieve efficient separation of these types of materials. More specifically, most sizing equipment does not apply a combination generally circular planar motion to one end of the screen, and a generally oblong linear reciprocating planar motion to the opposite end of the screen and the central portion of the screen. Rather, other types of forces, such as those generated by non-planar gyratory motions applied to the screens, are utilized in many prior art sizing apparatus. While this type of gyratory motion, as well as other types of motions such as those that generate generally vertical forces, work satisfactorily for sizing particles of relatively higher density materials, such prior art known vibrating motions are not the most efficient motions for achieving separation of particles of lower density materials.




However, certain known prior art particle sizing equipment has been developed in an attempt to efficiently achieve sizing and separation of particles of low-density materials. Rotex Inc. utilizes equipment which applies a generally circular planar motion to only one end of its screen, while also generally reciprocating the central portion and the opposite end of the screen in an oblong linear motion and in the same direction as the line of travel of material along the screen. However, this motion is achieved by a relatively complex crankshaft gear and leaf spring arrangement of parts, rather than one or more vibratory motors, together with bouncing balls disposed beneath the sloped screen to control screen blinding or clogging, to achieve sizing and separation of particles of low density materials. Similarly, Great Western Manufacturing Company, Inc. also utilizes a non-vibratory drive system rather than a vibratory motor to apply a generally large circular motion to the entire screen to enable sizing and separation. However, such sizing equipment is relatively complicated and expensive to manufacture and maintain, and still does not achieve desired levels of sizing and separation of particles of low-density materials.




The present invention solves a long-felt need in the material sizing art of how to efficiently size and separate particles of relatively low-density materials, by utilizing a certain vibratory motor placement and elongated sizing frame and screen, together with an arrangement of a plurality of various suspension assemblies, to aid material movement on the screen in such a manner as to achieve efficient sizing and separation of particles of low-density materials in equipment which is cost efficient to manufacture and maintain.




SUMMARY OF INVENTION




Objectives of the present invention include providing a sizing apparatus and method which efficiently sizes and separates particles of low-density materials, while utilizing a traditional vibratory motor.




Another objective of the present invention is to provide such a sizing apparatus and method which is relatively simple, inexpensive, reliable and easy to use and maintain.




These objectives and advantages are obtained by the apparatus for sizing and separating particles of a material of the present invention, the apparatus including a stand, a frame, means attached to the stand and the frame for movably suspending the frame on the stand, an enclosure mounted on the frame, the enclosure having a material input end, a central portion and a material output end, at least one screen mounted in the enclosure, the screen being inclined downwardly in a direction from the enclosure input end to the enclosure output end, and a vibratory motor mounted on the frame, so that a generally circular planar motion is imparted to the frame, the enclosure and the screen at the enclosure input end, and a generally oblong linear reciprocating motion is imparted at the enclosure central portion and the output end.











BRIEF DESCRIPTION OF THE DRAWINGS




The preferred embodiment of the invention, illustrative of the best mode in which applicant has contemplated applying the principles, is set forth in the following description and is shown in the drawings and is particularly and distinctly pointed out and set forth in the appended claims.





FIG. 1

is a perspective view of the sizing apparatus of the present invention for sizing and separating particles of relatively low-density materials;





FIG. 2

is a top plan view of the sizing apparatus shown in

FIG. 1

, with a portion broken away and hidden parts represented by broken lines;





FIGS. 2A

,


2


B,


2


C, and


2


D are views similar to

FIG. 2

, but in diagrammatic form, illustrating with arrows the motion of the vibratory motor, and with solid lines representing the motion imparted on the sizing apparatus frame and screen enclosure by the motor as compared to the starting position of the frame and screen enclosure illustrated by broken lines;





FIG. 3

is a side view of the sizing apparatus shown in

FIG. 1

, with hidden parts represented by broken lines;





FIG. 4

is a left-hand end view of the sizing apparatus shown in

FIG. 3

, with portions broken away and in section and the motor represented by phantom lines;





FIG. 5

is a right-hand end view of the sizing apparatus shown in

FIG. 3

, with hidden parts represented by broken lines; and





FIG. 6

is a fragmentary perspective view of a portion of the left-hand end of the sizing apparatus shown in

FIG. 3

, showing the disposition of the elastomeric suspension springs between the frame and the stand, with hidden parts represented by broken lines.











Similar numerals refer to similar parts throughout the drawings.




DESCRIPTION OF THE PREFERRED EMBODIMENT




The particle sizing and separating apparatus for low-density materials of the present invention is indicated generally at


10


, and is shown in

FIGS. 1 and 3

. Sizing apparatus


10


comprises a stand


15


, a frame


16


, a pair of suspension leaf springs each indicated at


12


and extending between one end of the stand and the frame, a plurality of suspension elastomeric springs each indicated at


70


and extending between an opposite end of the stand and the frame, a vibrator motor


18


, and a pair of screens


19




t


and


19




b


. Unless otherwise noted, all components of sizing apparatus


10


preferably are formed of a sturdy metal such as steel.




Stand


15


includes a generally rectangular-shaped base


20


comprising a pair of spaced, parallel, elongated side I-beams


21


, and a pair of spaced, parallel, elongated end I-beams


22


which extend between and are connected, by any suitable means such as welds, to the ends of side I-beams


21


to form sturdy base


20


(FIGS.


1


and


3


). An inverted generally U-shaped safety member


24


extends between and is connected, by any suitable means such as welds, to the top surface of each side I-beam


21


on the right-hand side or output end of base


20


. An upright pillar


14


is disposed on each corner of the left-hand or input end of base


20


, and connected by any suitable means such as welds. An elongated transverse I-beam


13


extends between and is connected, by any suitable means such as welds, to the top surface of each of upright pillars


14


. Three bottom hubs


17




b


are spaced along the top surface of I-beam


13


and are each secured thereto, by any suitable means such as welds, to complete the structure of stand


15


. A heavy-duty compression mount


88


is fastened, by any suitable means such as bolts, to the bottom surface of each corner of stand


15


, and each of the mounts in turn is fastened, by any suitable means such as bolts, to the surface, such as a concrete floor, on which sizing apparatus


10


rests. Mounts


88


substantially prevent the transmission of noise and vibration, caused by vibrator motor


18


, to the surface on which sizing apparatus


10


rests. A preferred compression mount


88


is sold by Tech Products Corporation, a Fabreeka Corporation, and is identified by Part No. 52137.




Frame


16


includes a generally rectangular-shaped frame base


26


(

FIGS. 1 and 3

) comprising a pair of spaced, parallel, tubular elongated side members


23


, and a pair of spaced, parallel, tubular elongated end members


25


which extend between and are connected, by any suitable means such as welds, to the ends of tubular side members


23


. Frame base


26


further includes a tubular transverse central member


28


which extends between and is connected at its ends to the midpoints of tubular side members


23


, by any suitable means such as welds (FIG.


2


). A cross-shaped frame-strengthening assembly


62


extends between each end member


25


and transverse central member


28


to complete sturdy frame base


26


.




Frame


16


also includes a pair of spaced, parallel vertical side plates


29


, each of which is secured, such as by welds, to a respective one of side members


23


and extends substantially the entire length of the side member. Each one of a plurality of strengthening gussets


32


is welded to a respective one of vertical side plates


29


and its respective side member


23


. The left-hand or input end of frame


16


further includes a vertically disposed motor mounting plate


11


that is attached to the exterior vertical wall of end member


25


, by any suitable means such as welds, and a vertically disposed internal support plate


27


that is similarly attached to the interior vertical wall of the end member. More specifically, internal support plate


27


extends between and is coped at each of its ends (not shown) to engage and partially surround side members


23


. Each end of support plate


27


is connected to its respective side member


23


by any suitable means such as welds. An end spring pad


81


extends between and is attached, by any suitable means such as welds, to the bottom surface of each end of mounting plate


11


and internal support plate


27


. A central spring pad


82


is similarly attached to the central portion of mounting plate


11


and internal support plate


27


, and is spaced from end spring pads


81


. A top hub


17




t


is connected, by any suitable means such as welds, to the center of the bottom surface of each one of pads


81


and


82


. A safety cylinder


80


is connected, by any suitable means such as welds, to the bottom surface of central pad


82


, and is concentric to top hub


17




t


, to complete frame


16


.




In accordance with one of the important features of the present invention, frame


16


is movably suspended on stand


15


at the left-hand or input end by cylindrical elastomeric springs


70


(

FIGS. 1-4

, and


6


). More specifically, each spring


70


is of equal size and shape, and is longer than safety cylinder


80


. A preferred spring


70


is formed of rubber and can be purchased from Firestone Industrial Products and is sold under the Marsh Mellow Trademark as part number W22-358-0180. Springs


70


each have an inside diameter sufficiently sized to frictionally fit about its respective top hub


17




t


of frame


16


and the corresponding bottom hub


17




b


of stand


15


. It is understood that other types of left-hand or input end suspension systems could be employed in the present invention without affecting its overall concept, such as other types or numbers of springs, such as coil springs.




Frame


16


is movably suspended on stand


15


at the right-hand or output end by spaced-apart leaf springs


12


. A preferred leaf spring


12


is sold by the 3M Company of Minneapolis, Minn., under the Scotchply brand name, is formed of fiberglass, and preferably is about three-eighths of an inch thick, about four inches wide, and about sixteen inches long. The bottom end of each leaf spring


12


is attached, by any suitable means such as nuts and bolts, to a transversely extending bracket


30




b


, which is in turn mounted on the upper surface of end I-beam


22


by any suitable means such as welds (

FIGS. 3 and 5

) The top end of each leaf spring


12


is similarly attached, by any suitable means such as nuts and bolts, to transversely extending bracket


30




t


, which in turn is mounted on the bottom surface of member


25


by any suitable means such as welds. It is understood that other types of right-hand or output end suspension systems also could be utilized in the present invention without affecting its overall concept, such as other types of springs, bushings, and the like.




In accordance with another important feature of the present invention, motor


18


is mounted by any suitable means, such as nuts and bolts, to the exterior face of mounting plate


11


on the input end of frame


16


(FIGS.


1


-


3


). Motor


18


is of a type which is well-known in the sizing equipment industry, and includes a counterweight


60


(

FIGS. 2A-3D

) located within the motor. A preferred vibratory motor


18


is sold by Italvibras Spa of Modena, Italy, and bears model number CD6-6600. As best shown in

FIG. 3

, the shaft (not shown) of motor


18


is disposed perpendicular to sizing apparatus base


20


, and due to the about ten degree slope of frame


16


, motor shaft


18


is offset about ten degrees from the planar surface of screens


19


. Vibratory motor


18


, due to its orientation relative to screens


19




t, b


and frame


16


, and the suspension springs


70


and


12


on the input and output ends, respectively, of sizing apparatus


10


, transmits a generally circular planar motion to frame


16


, a screen box


33


, and screens


19


nearest the left-hand input end of the sizing apparatus, and a generally oblong linear reciprocating motion at the central and leaf spring end of the apparatus, with the reciprocation being in the same direction as the line of travel of material along screens


19


, which will be described in greater detail hereinbelow. The frequency of motor


18


is about 600 revolutions per minute, and during operation, frame


16


, screen box


33


and screens


19


are displaced about one inch in each direction.




An elongated generally rectangular-shaped screen box or enclosure


33


is removably mounted on frame


16


(

FIGS. 1

, and


3


-


5


). Specifically, screen box


33


rests on top of and is suitably removably attached to vertical side plates


29


. Screen box


33


includes a pair of spaced, parallel, elongated sidewalls


34


, and a front end wall


35


which extends between and is connected to the front ends of sidewalls


34


. A rear end of screen box


33


is formed with an inlet opening


36


. Screen box


33


further includes a catch tray


37


which extends between and is connected to the lower ends of sidewalls


34


and front end wall


35


. The front end of catch tray


37


is formed with three discrete openings, and specifically, first, second, and third outlet openings or chutes


39




a


,


39




b


and


39




c


, respectively. A pair of generally diagonally disposed support members


61


are attached by any suitable means to the interior surfaces of the walls of screen box


33


, at each of the front and rear ends of the box (FIG.


2


), to provide additional structural support to the box.




A first top bracket


40




t


extends between and is attached by any suitable means to the interior surface of the output end of sidewalls


34


of screen box


33


, and a second top bracket


45




t


extends between and is attached to the interior surface of the input end of sidewalls


34


, for removably mounting top screen


19




t


in screen box


33


. Similarly, a first bottom bracket


40




b


extends between and is attached by any suitable means to the interior surface of the output end of sidewalls


34


of screen box


33


, and a second bottom bracket


45




b


extends between and is attached to the interior surface of the input end of sidewalls


34


, for removably mounting a bottom screen


19




b


in screen box


33


. Each screen


19


preferably can range in size from about two to about five feet wide and from about eight to about twenty feet long, and generally is within a mesh range of from about 2 to about 325 mesh (12 millimeters to 45 microns), and preferably from about 4 to about 100 mesh (5 millimeters to 150 microns), and is most suitable for low-density material dry sizing operations. Screens


19




t, b


, preferably each are a pretensioned frame screen, although adjustable tension hook strip screens can be used if desired without affecting the performance of sizing apparatus


10


. It is understood that, if desired, sizing apparatus


10


can be easily converted for use with a single screen


19


. Also, the angle of screens


19


is adjustable, and if desired, screen box


33


can be enclosed With a dust cover (not shown).




A material feed box


41


formed with an upper inlet opening


42


is mounted by any suitable means on the rear end of screen box


33


adjacent to and in communication with opening


36


.




In accordance with another important feature of the present invention, a material shaking apparatus


50


(

FIGS. 2 and 3

) is disposed between frame side members


23


directly below the central portion of screen box


33


. More particularly, a bracket


51


extends between and is attached by any suitable means to the interior surface of screen box sidewalls


34


. A thick, generally triangular-shaped impact transmission steel plate


52


is mounted on bracket


51


by any suitable means such as welding, and depends from the bracket and extends in the longitudinal or fore-aft direction relative to sizing apparatus


10


. A pair of spaced-apart angle irons


53


extend transversely between frame side members


23


generally below and adjacent to triangular plate


52


, and are attached to the bottom surface of screen box


33


. A channel member


54


is mounted on and between angle irons


53


, adjacent to triangular plate


52


and generally centered between frame side members


23


. An impactor


55


, of the type available from the Cleveland Vibrator Company of Cleveland, Ohio, is mounted on channel member


54


by bolts


56


. A preferred impactor is Model 1300. Such impactors deliver one impact at a maximum frequency of once every three seconds through a five-port spool valve. A timer is used to vary the cycle required. However, if desired, a ball tray or other devices which could exert a similar force could be alternatively utilized without affecting the overall concept of the present invention.




The operation of particle sizing apparatus


10


of the present invention will now be described. Vibrator motor


18


is actuated and its efficient circular motion about the generally vertically disposed axis of the motor creates the combination of a generally circular planar motion of frame


16


and attached screen box


33


at the motor end of the apparatus, and a generally oblong linear reciprocating motion at the central and leaf spring end of the apparatus with the reciprocation being in the same direction as the line of travel of material along screens


19




t


and


19




b


. A low-density material to be processed, such as fertilizer or plastic pellets (not shown), is supplied to inlet opening


42


of feed box


41


. The material travels through feed box


41


and passes through opening


36


(

FIGS. 1 and 3

) formed in the rear end of screen box


33


, and onto the input end of vibrating screen


19




t


. The material then travels downwardly-frontwardly on screen


19




t


, with undesirable larger-sized particles remaining on the screen and dropping off the front end of the screen and passing through first chute


39




a


for removal. Desirable smaller-sized particles pass downwardly through screen


19




t


and onto screen


19




b


, and such particles similarly simultaneously travel downwardly-frontwardly on screen


19




b


and drop through second chute


39




b


for further use. Still other desirable even smaller-sized particles pass downwardly through screen


19




b


and onto catch tray


37


of screen box


33


, and pass through third chute


39




c


for further processing.




In accordance with one of the main features of the present invention, the combination of a generally circular planar motion of screen box


33


at the input or left-hand end of apparatus


10


and a generally oblong linear reciprocating motion at the output or right-hand end of the apparatus, with the reciprocation being in the same direction as the line of travel of material along screens


19


, as best illustrated in the elapsed time series of drawings

FIGS. 2A

,


2


B,


2


C and


2


D, aids in the efficient dry sizing and separation of low-density materials. The orientation and location of motor


18


, and the circular motion of motor counterweight


60


, results in such a combination motion. Specifically, motor counterweight


60


moves in the clockwise direction as best illustrated in

FIGS. 2A

,


2


B,


2


C and


2


D. In FIG,


2


A, motor counterweight


60


and screen box


33


are stationary. As motor counterweight


60


begins to rotate in a clockwise circular motion within motor


18


, the resulting force causes the portions of frame


16


, screen box


33


and screens


19


nearest motor


18


, to move in a generally circular planar motion, and causes the central portion and right-hand end of frame


16


, screen box


33


and screens


19


to move in a generally oblong linear reciprocating motion, as best illustrated in

FIGS. 2B

,


2


C and


2


D.




The described combination of a generally circular planar motion of sizing apparatus


10


at the left-hand or input end and a generally oblong linear reciprocating motion at the right-hand or output end is superior to prior art low-density particle sizing apparatus which utilize other types of motions to move material along the apparatus, such as non-planar gyratory and vertical motions. Sizing apparatus


10


is also superior to prior art low-density particle sizing apparatus which achieve a motion similar to that of the present invention, but which utilize more complicated, expensive apparatus to achieve such motion, such as gears. The present invention achieves the desired motion, and resulting low-density particle sizing, by utilizing a traditional vibratory motor


18


in a certain orientation, in combination with suspension components which include elastomeric springs


70


and leaf springs


12


. Vibratory motor


18


is less costly, more durable and more efficient than other alternatives, such as gear-driven apparatus. The elongated screen box


33


also aids in strengthening the overall structure of the box and minimizes potential damage to the box due to the high-torque combination motion. The aforementioned support members


61


also contribute to the stability of screen box


33


, and cross-shaped frame strengthening assemblies


62


enable frame


16


to withstand such forces. Nonetheless, in the event that leaf springs


12


fail, safety member


24


serves as a safety device and will catch the right-hand or output end of frame


16


and prevent it from further falling. Similarly, on the left-hand or input end of frame


16


, safety cylinder


80


will prevent frame


16


from falling further in the event that elastomeric springs


70


fail.




While the combination of a generally circular planar motion at the left-hand or input end of screens


19


and a generally oblong linear reciprocating motion at the right hand or output end of screens


19


does promote the preferred linear movement of material on screens


19


, the linear movement of said material is enhanced by the downward-frontward slope of the screens. Nonetheless, material moving down screens


19


can stick to or coat the mesh of the screens due to the fine particles of low-density materials being processed by sizing apparatus


10


. Impactor


55


of material shaking apparatus


50


transmits a force to screens


19


to shake the sticking or coating low-density material fine particles from the mesh of the screens. More particularly, impactor


55


transmits an upward force in a direction perpendicular to the plane of screens


19


via channel member


54


and angle irons


53


, which in turn transfer the impact into triangular plate


52


and bracket


51


, which imparts the force into screen


19




b


. The force also transmits upward through screen box sidewalls


34


and into screen


19




t


. Such impact shakes any fine particles of the material which is sticking to or coating the mesh of screens


19


.




The improved sizing apparatus


10


of the present invention can also be used for scalping, dedusting, polishing and removal of trash and foreign materials. Sizing apparatus


10


also is relatively economical to manufacture, use and maintain.




Accordingly, the particle sizing apparatus for low-density materials of the present invention is simplified, provides an effective, safe, inexpensive and reliable sizing apparatus and method which achieves all of the enumerated objectives, provides for eliminating difficulties encountered with prior low-density material sizing apparatus and methods, and solves problems and obtains new results in the art.




In the foregoing description, certain terms have been used for brevity, clearness and understanding; but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such terms are used for descriptive purposes and are intended to be broadly construed.




Moreover, the description and illustration of the invention is by way of example, and the scope of the invention is not limited to the exact details shown or described.




Having now described the features, discoveries and principles of the invention, the manner in which the improved sizing apparatus and method is constructed, arranged and used, the characteristics of the construction, arrangement and method steps, and the advantageous, new and useful results obtained; the new and useful structures, devices, elements, arrangements, parts and combinations are set forth in the appended claims.



Claims
  • 1. An apparatus for sizing and separating particles of a material, said apparatus including:a) a stand; b) a frame; c) means attached to said stand and said frame for movably suspending the frame on the stand; d) an enclosure mounted on the frame, said enclosure having a material input end, a central portion and a material output end; e) at least one screen mounted in the enclosure, said screen being inclined downwardly in a direction from said enclosure input end to said enclosure output end; and f) a vibratory motor mounted on the frame, so that a generally circular planar motion is imparted to said frame, said enclosure and said screen at said enclosure input end, and a generally oblong linear reciprocating motion is imparted at said enclosure central portion and said output end.
  • 2. The apparatus of claim 1, in which said frame is generally rectangular-shaped and includes a pair of spaced-apart elongated sides; in which said enclosure and said screen each is elongated; in which said vibratory motor is mounted on an end of said frame adjacent to said enclosure input end and; in which a shaft of said motor is disposed generally perpendicular to a horizontal surface upon which said stand is disposed; and in which a counterweight is contained in the motor.
  • 3. The apparatus of claim 2, in which said screen has a mesh of from out 4 to about 100; in which the screen has a width of from about two feet to about five feet a length of from about eight feet to about twenty feet; in which each of said frame, said enclosure and said screen is displaced during operation of said apparatus about one inch; in which said motor operates at a frequency of about 600 revolutions per minute; and in which said material is a generally low-density material.
  • 4. The apparatus of claim 4, in which top and bottom screens are removably mounted in said enclosure in a generally vertically spaced, parallel relationship.
  • 5. The apparatus of claim 4, in which said enclosure has an inlet opening for receiving material at said input end; in which said enclosure output end is formed with first, second and third outlet openings; in which particles of said material failing to pass through said top screen pass through said first outlet opening; in which particles of the material which pass through said top screen and fail to pass through said bottom screen pass through said second outlet opening; and in which particles of said material which pass through said bottom screen pass through said third outlet opening.
  • 6. The apparatus of claim 4, in which material shaking means is located adjacent to said screens for applying a force to the screens to aid in shaking loose particles of said material stuck to the screens.
  • 7. The apparatus of claim 6, in which the material shaking means is an impactor device mounted on an exterior bottom surface of said enclosure generally adjacent to the central portion of said enclosure; and in which said impactor device transmits a force to the enclosure and to said screens at predetermined time intervals to aid in shaking loose particles of said material stuck to the screens.
  • 8. The apparatus of claim 7, in which a generally triangular-shaped plate is mounted on an interior bottom surface of the enclosure generally adjacent to said impactor device; in which said plate extends upwardly between said enclosure interior bottom surface and contacts a member which extends transversely across generally the entire width of said bottom screen and generally abuts said screen; and in which an elongated periphery of said plate extends in the direction of travel of the material along the screens.
  • 9. The apparatus of claim 2, in which a plurality of elastomeric shock absorbers are mounted on a bottom surface of said stand and extend between said stand and said horizontal surface upon which said stand is disposed.
  • 10. The apparatus of claim 1, in which at least one cross-shaped frame-strengthening assembly is mounted on said frame; in which at least a pair of support members are mounted on said enclosure; and in which the enclosure is removably mounted on the frame.
  • 11. A method of sizing and separating particles of a generally low-density material, using an apparatus comprising a stand, a frame, means attached to said stand and said frame for movably suspending the frame on the stand, an enclosure mounted on the frame, said enclosure having a material input end, a central portion and a material output end, at least one screen mounted in the enclosure, said screen being inclined downwardly in a direction from said enclosure input end to said enclosure output end, and a vibratory motor mounted on the frame for imparting a motion to said frame, said enclosure, and said screen, said method including the steps of:a) actuating said vibratory motor for imparting a generally circular planar motion to said frame, said enclosure and said screen at said enclosure input end, and for imparting a generally oblong linear reciprocating motion at said enclosure central portion and said output end; and b) supplying said generally low-density material onto an upper end of said screen adjacent to said enclosure material input end, whereby said material advances downwardly on said screen from said enclosure input end to said enclosure output end.
  • 12. The method of claim 11, in which said frame is generally rectangular-shaped and includes a pair of spaced-apart elongated sides; in which said enclosure and said screen each is elongated; in which said vibratory motor is mounted on an end of said frame adjacent to said enclosure input end; in which a shaft of said motor is disposed generally perpendicular to a horizontal surface upon which said stand is disposed; and in which a counterweight is contained in the motor.
  • 13. The method of claim 12, in which said screen has a mesh of from about 4 to about 100; in which the screen has a width of from about two feet to about five feet and a length of from about eight feet to about twenty feet; in which each of said frame, said enclosure and said screen is displaced about one inch during operation of said apparatus; and in which said motor operates at a frequency of about 600 revolutions per minute.
  • 14. The method of claim 13, in which top and bottom screens are removably mounted in said enclosure in a generally vertically spaced, parallel relationship.
  • 15. The method of claim 14, in which said enclosure has an inlet opening for receiving material at said input end; in which said enclosure output end is formed with first, second and third outlet openings; in which particles of said material failing to pass through said top screen pass through said first outlet opening; in which particles of the material which pass through said top screen and fail to pass through said bottom screen pass through said second outlet opening; and in which particles of said material which pass through said bottom screen pass through said third outlet opening.
  • 16. The method of claim 12, in which a plurality of elastomeric shock absorbers are mounted on a bottom surface of said stand and extend between said stand and said horizontal surface upon which said stand is disposed for absorbing dynamic loads during operation of the apparatus.
  • 17. The method of claim 11, in which at least one cross-shaped frame-strengthening assembly is mounted on said frame; in which at least a pair of support members are mounted on said enclosure; and in which the enclosure is removably mounted on the frame.
  • 18. The method of claim 11, in which material shaking means is located adjacent to said screen for applying a force to the screen to aid in shaking loose particles of said material coated on the screen.
  • 19. An apparatus for sizing and separating particles of a material, said apparatus including:a) a stand; b) a frame that is generally rectangular-shaped and includes a pair of spaced-apart elongated sides; c) an elongated enclosure mounted on the frame, said enclosure having a material input end, a central portion and a material output end; d) a plurality of elastomeric springs mounted on and extending between said stand and said frame adjacent to said enclosure input end; e) a pair of leaf springs mounted on and extending between said stand and said frame adjacent to said enclosure output end; thereby cooperating with said plurality of elastomeric springs for movably suspending said frame on said stand; f) at least one elongated screen mounted in said enclosure, said screen being inclined downwardly in a direction from said enclosure input end to said enclosure output end; g) a vibratory motor mounted on an end of said frame adjacent to said enclosure input end, so that a generally circular planar motion is imparted to said frame, said enclosure and said screen at said enclosure input end, and a generally oblong linear reciprocating motion is imparted at said enclosure central portion and said output end; and h) said motor including a counterweight and a shaft that is disposed generally perpendicular to a horizontal surface upon which said stand is disposed.
  • 20. A method of sizing and separating particles of a generally low-density material, using an apparatus comprising a stand, a generally rectangular-shaped frame that includes a pair of spaced-apart elongated sides, an elongated enclosure mounted on the frame, said enclosure having a material input end, a central portion and a material output end, a plurality of elastomeric springs mounted on and extending between said stand and said frame adjacent to said enclosure input end, and a pair of leaf springs mounted on and extending between said stand and said frame adjacent to said enclosure output end, whereby said plurality of elastomeric springs and said pair of leaf springs cooperate to movably suspend the frame on the stand, at least one elongated screen mounted in the enclosure, said screen being inclined downwardly in a direction from said enclosure input end to said enclosure output end, and a vibratory motor mounted on an end of said frame adjacent to said enclosure input end for imparting a motion to said frame, said enclosure, and said screen, the motor including a counterweight and a shaft that is disposed generally perpendicular to a horizontal surface upon which said stand is disposed, said method including the steps of:a) actuating said vibratory motor for imparting a generally circular planar motion to said frame, said enclosure and said screen at said enclosure input end, and for imparting a generally oblong linear reciprocating motion at said enclosure central portion and said output end; and b) supplying said generally low-density material onto an upper end of said screen adjacent to said enclosure material input end, whereby said material advances downwardly on said screen from said enclosure input end to said enclosure output end.
Parent Case Info

This application claims the benefit of provisional application 60/294,660 filed on May 31, 2001.

US Referenced Citations (9)
Number Name Date Kind
529872 Morse Nov 1894 A
2204379 Overstrom Jun 1940 A
4402826 Uchitel et al. Sep 1983 A
5037535 Bruderlein Aug 1991 A
5301814 Lower et al. Apr 1994 A
5301815 Chauvin et al. Apr 1994 A
5595306 Hukki et al. Jan 1997 A
5730297 Lower et al. Mar 1998 A
5927513 Hart Jul 1999 A
Non-Patent Literature Citations (4)
Entry
Rotex Inc. flyer entitled “Rotex® Screeners” email address http://www.rotex.com/rotex/screeners/rotex.shtml; copyright 1999 Rotex Inc.
Rotex Inc. flyer entitled “3 ways ROTEX accuracy increases your profits”—Rotex Inc. 1230 Knowlton Street, Cincinnati, OH 45223.
Rotex Inc. flyer entitled “How to control screen blinding” No. 7 of a series, Catalog 806, Rotex Inc, 1230, Knowlton Street, Cincinnati, OH 45223.
Great Western flyer entitled “Stainless Steel Tru-Balance Sifter” (2 pages) Great Western Manufacturing Company, Inc., 208 Choctaw, P.O. Box 149, Leavenworth, KS 66048-0149.
Provisional Applications (1)
Number Date Country
60/294660 May 2001 US