Apparatus and methods for stripping cotton

Information

  • Patent Grant
  • 6543091
  • Patent Number
    6,543,091
  • Date Filed
    Monday, January 7, 2002
    22 years ago
  • Date Issued
    Tuesday, April 8, 2003
    21 years ago
Abstract
Disclosed are methods and apparatus for stripping petals from cotton balls. In one embodiment, the cotton stripper includes an impacter for at least partially opening the cotton balls, a first cleaning mechanism to discard petals removed by the impacter, and a cotton separator for removing the remaining petals from the cotton balls. In one embodiment, the cotton separator includes a first large roller, which receives and traps the at least partially opened cotton balls from the first cleaning mechanism. The at least partially opened cotton balls rotate with the first large roller toward a first net. Petals on the cotton balls are stripped off by the first net. Petals removed by the first net fall toward the bottom of the cotton separator. A first small roller then removes the first stripped cotton balls from the first large roller. Processed cotton balls are then stored in an output area.
Description




FIELD OF THE INVENTION




The present invention relates generally to the field of cotton processing and, more specifically, to stripping petals from cotton balls.




BACKGROUND OF THE INVENTION




The separation of petals from cotton balls can be a very labor-intensive effort. In order to minimize the effort required to separate petals from cotton balls, cotton separators have been used. Typically, cotton separators use crushers to crush the petals. However, crushing the petals can result in small pieces of petals sticking to the cotton ball. The small pieces of petals that stick to the cotton ball are very difficult to separate from the cotton ball. In addition, it is possible for the small pieces of petal to reach the last stage of a fiber produced from the cotton ball, and the small pieces of petal can ultimately damage the whole fabric.




One of the components used in existing cotton separators are large rollers with a wire mesh around the circumference of the roller. The wire mesh on the rollers is frequently damaged during operation as small stones and hard petals can cause considerable damage to the wire mesh. The damage to the wire mesh results in frequent replacement of the mesh. In some instances the wire mesh has to be replaced every 15 days. The replacement of the wire mesh can be costly and may prevent the further processing of cotton for 3 to 4 days.




Existing cotton separators generally require at least three workers to operate the machine. One worker pours cotton balls encased in petals in the hopper of the cotton separator. Another worker clears away striped petals, and another worker collects stripped cotton balls. In addition, workers collecting stripped petals can be exposed to rotating parts, which can potentially injure the workers.




Existing cotton separators do not remove all of the petals from the cotton balls during processing, necessitating reprocessing of the cotton balls to remove any petals that remain. This reprocessing of cotton balls results in higher production costs.




SUMMARY OF THE INVENTION




The present invention relates to an apparatus for stripping petals from cotton balls. In one embodiment, the apparatus includes a hopper to store raw cotton balls encased in petals, an impacter to partially open the raw cotton balls and remove some of the petals, a first cleaning mechanism to discard some of the petals that are removed by the impacter, and a cotton separator. The cotton separator includes a first large roller encased in a first mesh material rotating at a first speed to capture the at least partially opened cotton balls, a first net located at a circumferential position adjacent to the first large roller to strip off petals, and a first small roller rotating at a second speed to take the first stripped cotton balls from the first large roller. The second speed of the first small roller is faster than the first speed of the first large roller.




In another embodiment of the present invention, the cotton separator also includes a second large roller encased in the first mesh material rotating at the first speed to capture the first stripped cotton balls, a second net located at a circumferential position adjacent to the second large roller to strip off petals, and a second small roller encased in the second mesh material rotating at the second speed to take the second stripped cotton balls from the second large roller.




In yet another embodiment of the present invention, the cotton separator also includes a third large roller located below the first large roller and the second large roller The third large roller is encased in the first mesh material rotating at the first speed to capture the first or second stripped cotton balls. The cotton separator further includes a third net located at a circumferential position adjacent to the third large roller to strip off petals, and a third small roller encased in the second mesh material rotating at the second speed to take the second or third stripped cotton balls from the second large roller.




In yet another embodiment of the present invention, the cotton separator also includes a worm wheel to remove petals from the cotton separator.




In yet another embodiment of the present invention, the impacter includes a shaft, a plurality of spikes connected to the shaft, the plurality of spikes is connected to the shaft in a worm wheel configuration, and the shaft is supported by a housing.




Finally, in yet another embodiment of the present invention, the apparatus further includes a suction mechanism to both supply raw cotton balls to the impacter and remove impurities from the raw cotton balls.











BRIEF DESCRIPTION OF THE DRAWINGS




The foregoing and other objects, features, and advantages of the present invention, as well as the invention itself, will be more fully understood from the following description of various embodiments, when read together with the accompanying drawings, in which:





FIG. 1

is a front view of an embodiment of the current invention illustrating a cotton stripper;





FIG. 2

is a schematic diagram of an embodiment of the current invention illustrating licker-in wire;





FIG. 3

is a schematic diagram of an embodiment of the current invention illustrating doffer wire;





FIG. 4

is a back view of an embodiment of the current invention illustrating the cotton stripper;





FIG. 5

is a side view of an embodiment of the current invention illustrating a cotton stripper; and





FIG. 6

is a front view of another embodiment of the current invention illustrating a cotton stripper.











DESCRIPTION OF PREFERRED EMBODIMENT





FIG. 1

illustrates a preferred embodiment of a cotton stripper


10


for stripping petals from cotton balls. The cotton stripper


10


includes a feeder


11


, where the feeder


11


includes a hopper


12


, a feed roller


14


, and an impacter


16


. A user pours cotton balls encased in petals into the hopper


12


. The feed roller


14


passes the cotton balls encased in petals to the impacter


16


.




The impacter


16


includes a shaft


18


, and a plurality of spikes


20


connected to the shaft


18


, which is supported by a housing


19


. The housing


19


can be made from any durable metal, plastic, or composite material known to those skilled in the art. In another embodiment, more than one shaft with a plurality of spikes can be used.




The plurality of spikes


20


are arranged in a worm wheel configuration having the plurality of spikes oriented at different angles to transport cotton balls with petals from the first end


22


of the impacter


16


to the second end


24


of the impacter


16


. In one embodiment, the shaft


18


can rotate from about 100 rpm to 1,250 rpm. In another embodiment, the shaft


18


can rotate from about 500 rpm to 1,000 rpm. In a most preferred embodiment, the shaft


18


can rotate at about 750 rpm.




The cotton balls encased in petals strike the rotating plurality of spikes


20


, which causes the petals to at least partially split open from the impact with the plurality of spikes


20


. In addition, the partially opened cotton balls are then thrown by the plurality of spikes


20


into the housing


19


, which further opens the partially opened cotton balls. The combination of impacts from the plurality of spikes


20


and the housing


19


causes the cotton balls encased in petals to open almost completely.




There is very little clearance between the plurality of spikes


20


and the housing


19


. In one embodiment, the clearance between the plurality of spikes


20


and the housing


19


can range from about 0.6 in. to 1.6 in. Grooves (not shown) are formed inside the housing


19


to act as a guide for forward motion of the at least partially opened cotton balls. The combination of the plurality of spikes


20


configured in a worm wheel configuration, the small clearance between the plurality of spikes


20


and the housing


19


, along with the grooves in the housing


19


cause the at least partially opened cotton balls to move toward the second end of the impacter


24


in an efficient manner.




The at least partially opened cotton balls and petals are then moved to, a transporter


27


, which includes a first cleaning mechanism


28


The first cleaning mechanism


28


includes a plurality of spiked rollers


30


. The plurality of spiked rollers


30


are configured to pass the at least partially opened cotton balls o first spiked roller


32


in the plurality spiked rollers


30


to the last spiked roller


34


in the plurality of spiked rollers. In one embodiment, the plurality of spiked rollers


30


are oriented in an upward direction.




The first cleaning mechanism


28


allows petals that have been removed by the impacter


16


to be separated from the at least partially opened cotton balls as the at last partially opened cotton balls are transported along the plurality of spiked rollers


30


.




The at least partially opened cotton balls are transported from the first cleaning mechanism


28


to the cotton separator


36


. In one embodiment, the cotton separator includes a first large roller


38


, a first net


40


circumferentially adjacent to the first large roller


38


, and a first small roller


42


. The first net


40


is positioned just below the first large roller


38


. In one embodiment, the first large roller


38


is about 10 inches to 50 inches in diameter. In another embodiment, the first large roller


38


is about 20 inches to 40 inches in diameter. In a preferred embodiment, the first large roller


38


is about 26 inches in diameter.




The first large roller


38


is encased in a first material


44


, which in one embodiment can be a licker-in wire. Licker-in wire is used as a clothing in carding machines for the purpose of opening fiber tufts. Licker-in wire has sharp points, which are used to penetrate the at least partially opened cotton balls. Persons skilled in the art can choose the parameters of the licker-in wire to meet the needs of a particular application.

FIG. 2

illustrates an embodiment of one type of licker-in wire where the spikes can have a height range h


L


from 0.20 to 0.22 inches, a front angle range β


L


from 55 to 90 degress and a back angle β


L


range from 25 to 50 degrees. In one embodiment, the licker-in wire can be model number D2811506042 from Indian Card Clothing based in Pune, India.




In one embodiment, the first large roller


38


rotates from about 50 to 1,000. In another embodiment, the first large roller


38


rotates from about 100 to 500. In a preferred embodiment, the-first large roller


38


rotates at about 250 rpm.




The first small roller


42


is adjacent to the first large roller


38


. In one embodiment, the first small roller


42


and is about {fraction (1/16)} to ¾ of the size of the first large roller


38


. In another embodiment, the first small roller


42


and is about ⅛ to ½ of the size of the first large roller


38


. In a preferred embodiment, the first small roller


42


is about a ¼ of the size of the first large roller


38


. The first small roller


42


is encased in a second material


46


, which in one embodiment can be a doffer wire. Doffer wire is a clothing used in carding machines for collecting condensed masses of fibers circulating on a cylinder. In the present application, as described in more detail below, the doffer wire is used as the second material


46


to collect first stripped cotton balls from the first large roller


38


.

FIG. 3

illustrates an embodiment of one type of doffer wire where the doffer wire can have a height range h


D


from 0.16 to 0.20 inches, a front angle range α


D


from 50 to 60 degrees and a back angle β


D


from 20 to 42 degrees. In one embodiment, the doffer wire can be model number L0006557040 from Indian Card Clothing. Persons skilled in the art can choose the parameters of the doffer wire to meet the needs of a particular application.




In one embodiment, the first small roller


42


rotates from about 200 to 5,000 rpm. In another embodiment, the first small roller


42


rotates from about 500 to 2,500 rpm. In a preferred embodiment, the first small roller


42


rotates at about 1,000 rpm.




The first large roller


38


encased in the first material


44


, receives and traps the at least partially opened cotton balls from the first cleaning mechanism


28


. The at least partially opened cotton balls now rotate with the first large roller


38


toward the first net


40


. There is a very tight clearance between the first large roller


38


and first net


40


, so that petals still remaining on the cotton balls are stripped off by the first net. In a preferred embodiment, the clearance between the first large roller


38


and the first net


40


is adjustable and can be varied from about 0.1 inches to 0.6 inches. Petals that are removed by the first net


40


fall toward the bottom


37


of the cotton separator


36


. The first small roller


42


then removes the first stripped cotton balls from the first large roller


38


.




In one embodiment, the cotton separator


36


further includes a second large roller


48


, a second net


50


adjacent to the second large roller


48


, and a second small roller


52


. The second net


50


is positioned just below the second large roller


48


. The second large roller


48


is encased in first material


44


. In one embodiment, the second large roller


48


is from 10 inches to 50 inches in diameter. In another embodiment, the second large roller


48


is about 20 inches to 40 inches in diameter. In a preferred embodiment, the second large roller


48


is about 26 inches in diameter.




In one embodiment, the second large roller


48


rotates at about 50 to 1,000. In another embodiment, the second large roller


48


rotates at about 100 to 500. In a preferred embodiment, the second large roller


48


rotates at about 250 rpm.




The second small roller


52


is positioned adjacent to the second large roller


48


. In one embodiment, the second small roller


52


and is about {fraction (1/16)} to ¾ of the size of the second large roller


48


. In another embodiment, the second small roller


52


is about ⅛ to ½ of the size of the second large roller


48


. In a preferred embodiment, the second small roller


52


is about ¼ of the size of the second large roller


48


. The second small roller


52


is also encased in the second material


46


.




In one embodiment, the second small roller


52


rotates from about 250 to 5,000 rpm. In another embodiment, the second small roller


52


rotates from about 500 to 2,500 rpm. In a preferred embodiment, the second small roller


52


rotates about 1,000 rpm.




The second large roller


48


encased in the first material


44


, receives and traps the first stripped cotton balls from the first small roller


42


. The at least partially opened cotton balls now rotate with the second large roller


48


toward the second net


50


. There is a very tight clearance between the second large roller


48


and second net


50


, so that petals still remaining on the cotton balls are stripped off by the second net


50


. In a preferred embodiment, the clearance between the second large roller


48


and the second net


50


is adjustable and can be varied from around 0.1 inches to 0.6 inches. Petals that are removed by the second net


50


fall toward the bottom


37


of the cotton separator


36


. The second small roller


52


then removes the second stripped cotton balls from the second large roller


48


.




In another embodiment, the cotton stripper further includes a third large roller


58


, a third net


60


and a third small roller


62


. The third large roller


58


, third net


60


adjacent to the third large roller


58


, and third small roller


62


are located below first large roller


38


and second large roller


48


to process any cotton balls that were stripped off by the first net


40


or second net


50


. The third net


60


is positioned just below the third large roller


58


. The third large roller


58


is encased in the first material


44


. In one embodiment, the third large roller


58


is about 10 inches to 50 inches in diameter. In another embodiment, the third large roller


58


is about 20 inches to 40 inches in diameter. In a preferred embodiment, the third large roller


58


is 18 inches in diameter.




In one embodiment, the third large roller


58


rotates from about 50 to 1,000. In another embodiment, the third large roller


58


rotates from about 100 to 500. In a preferred embodiment, the third large roller


58


rotates at about 200 rpm.




The third small roller


62


is adjacent to the third large roller


58


. In one embodiment, the third small roller


62


is about {fraction (1/16)} to ¾ of the size of the third large roller


58


. In another embodiment, the third small roller


62


is about ⅛ to ½ of the size of the third large roller


58


. In a preferred embodiment, the third small roller


62


is about ¼ of the size of the third large roller


58


. The third small roller


42


is also encased in the second material


46


.




In one embodiment, the third small roller


62


rotates from about 200 to 500 rpm. In another embodiment, the third small roller


62


rotates from about 500 to 2,500 rpm. In a preferred embodiment, the third small roller


62


rotates at 1,000 rpm.




The third large roller


58


encased in the first material


44


, receives and traps cotton balls that were stripped off from the first large roller


38


by the first net


40


or cotton balls stripped off the second large roller


48


by the second net


50


. The first or second stripped cotton balls now rotate with the third large roller


58


toward the third net


60


. There is a very tight clearance between the third large roller


58


and third net


60


, so that petals still remaining on the cotton balls are stripped off by the third net


60


. In a preferred embodiment, the clearance between the third large roller


58


and the third net


60


is adjustable and can be varied from around 0.1 inches to 0.6 inches. Petals that are removed by the third net


60


fall toward the bottom of the cotton separator


37


.




The materials used for the first through third large rollers and the first through third small rollers can be manufactured from a large array of metals or alloys known to those skilled in the art. In one embodiment, the large rollers can be made from cast iron and the small rollers can be made from mild steel.




In one embodiment, the cotton separator


36


further comprises an output area


70


for storing second and third stripped cotton balls.




In another embodiment, the cotton separator


36


further comprises a worm wheel


64


, located proximate the bottom of the cotton separator


37


to transport stripped petals out of the cotton separator


36


.




The elements of the cotton stripper


10


can be driven in an almost unlimited variety of ways. In one embodiment the first small roller


42


, the second small roller


52


, and the third small roller


62


can be driven by a first motor


72


, first motor belt


73


and small rotor belt


74


. The first motor


72


can be selected from a large range of horsepower depending on the particular application. In one embodiment, the first motor


72


can have a horsepower of about 2 horsepower.




In one embodiment, the first large roller


38


, the second large roller


48


and the third large roller


58


can be driven by a second motor


76


, a second motor belt


77


and a large roller belt


78


as shown in FIG.


4


. In addition, as shown in

FIG. 1

, the worm wheel


64


can be driven by a worm wheel belt


80


running off the third large roller


58


. Further, the plurality of spiked rollers


30


of the first cleaning mechanism


28


can be driven by spiked roller belt


82


running off first large roller


38


. The second motor


76


can be selected from a large range of horsepower depending on the particular application. In one embodiment, the second motor


76


can have a horsepower of about 1 horsepower.




In one embodiment, as shown in

FIG. 5

, the feed roller


14


in the hopper


12


can be driven by a third motor


84


via a third motor belt


86


, a plurality of gear boxes


88


, a plurality of hopper belts


90


, and a plurality of hopper pulleys


92


. The shaft


18


with the plurality of spikes


20


can be driven by one of the gear boxes


92


. The third motor


84


can be selected from a large range of horsepower depending on the particular application. In one embodiment, the third motor


84


can have a horsepower of about 3 horsepower. In one embodiment, the cotton stripper


10


can process 900 pounds of cottons balls encased in petals per hour.




In yet another embodiment, shown in

FIG. 6

, a suction mechanism


90


can be added to the cotton stripper


10


to suck raw cotton balls from the hopper


12


′ via a flexible tube


92


to the impacter


16


′. The suction mechanism


90


is sized to allow raw cotton balls to be sucked up to the impacter


16


′, but the suction provided is not strong enough to suck impurities like stones, which fall out through rejection port


94


. By removing impurities through the use of the suction mechanism


90


, the life of the licker-in wire will be improved. Additionally, a suction port


94


can be positioned near the impacter


16


′ to suck away small impurities such as dust from the impacter


16


′.




In the embodiment shown in

FIG. 6

, the number of spiked rollers


30


′ can be reduced to two spiked rollers due to the cleaning of the cotton balls provided by the suction mechanism


90


, and because the section mechanism


90


has also lifted the cotton ball closer to the height of the first large roller


38


′.




In another embodiment, a second plurality of spiked rollers


96


can be added after the second small roller


52


′ to remove any impurities left on the second stripped cotton balls while the second stripped cotton balls being transported to the output area


70


′. Inclined plates


98


can be used to guide any cotton balls that were stripped off by the first net


40


′ or the second net


50


′ to be further processed by the third large roller


58


′, the third small roller


62


′ and the third net


60


′. Cotton ball processed by the third large roller


58


′, the third small roller


62


′ and the third net


60


′ are then guided by inclined plate


100


to a second output area


102


.




Variations, modifications, and other implementations of what is described herein will occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the invention is to be defined not by the preceding illustrative descriptions, but instead by the following claims.



Claims
  • 1. A cotton stripper, the cotton stripper comprising:a hopper to store raw cotton balls encased in petals; an impacter in process communication with the hopper; a first cleaning mechanism in process communication with the impacter; a cotton separator in process communication with the first cleaning mechanism, the cotton separator comprising; a first large roller encased in a first mesh material rotating at a first speed; a first net located at a circumferential position adjacent to the first large roller; and a first small roller encased in a second mesh material rotating at a second speed and adjacent the first large roller, wherein the impacter at least partially opens the raw cotton balls and removes some petals, the first cleaning mechanism discards petals that were removed by the impacter, the first large roller captures the at least partially opened raw cotton balls, the first net strips off petals, and the first small roller takes the first stripped cotton balls from the first large roller.
  • 2. The invention according to claim 1 wherein the second speed is faster than the first speed.
  • 3. The invention according to claim 1 wherein the cotton separator further comprises:a second large roller encased in the first mesh material rotating at the first speed; a second net located at a circumferential position adjacent to the second large roller; and a second small roller encased in the second mesh material rotating at the second speed and adjacent to the second large roller, wherein the second large roller captures the first stripped cotton balls, the second net strips off petals and the second small roller takes the second stripped cotton balls from the second large roller.
  • 4. The invention according to claim 3 wherein the cotton separator further comprises:a third large roller encased in the first mesh material rotating at the first speed; a third net located at a circumferential position adjacent to the third large roller; and a third small roller encased in the second mesh material rotating at the second speed and adjacent the third large roller, wherein the third large roller, the third net, and third small roller are below the first large roller, the first net, the first small roller, the second large roller, the second net and the second small roller, and further wherein, the third large roller captures the first or second stripped cotton balls, the third net strips off petals and the third small roller takes the second or third stripped cotton balls from the third large roller.
  • 5. The invention according to claim 1 wherein the first mesh material comprises licker-in wire.
  • 6. The invention according to claim 1 wherein the second mesh material comprises doffer wire.
  • 7. The invention according to claim 1 wherein the cotton separator further comprises a worm wheel to remove petals from the cotton separator.
  • 8. The invention according to claim 1 further comprising an output area in process communication with the cotton separator for storing cotton balls after they pass through the cotton separator.
  • 9. The invention according to claim 1 wherein the hopper comprises a feed roller to transport the raw cotton balls encased in petals to the impacter.
  • 10. The invention according to claim 1 wherein the impacter comprises:a shaft; a plurality of spikes connected to the shaft, wherein the spikes are arranged to form a worm wheel configuration; and a housing to support the shaft.
  • 11. The invention according to claim 10 wherein the housing further comprises grooves.
  • 12. The invention according to claim 1 wherein the first cleaning mechanism comprises a plurality of spiked rollers.
  • 13. The invention according to claim 12 wherein the plurality of spiked rollers are configured to pass the at least partially opened raw cotton balls from a first spiked roller in the plurality of spiked rollers to a last spiked roller in the plurality of spiked rollers.
  • 14. The invention according to claim 1 further comprising a suction mechanism in process communication with the hopper and the impacter.
  • 15. A method for stripping petals from cotton balls, the method comprising:loading raw cotton balls encased in petals into a hopper; impacting the raw cotton balls encased in petals to at least partially open the cotton balls; discarding petals that were removed by the impacter; capturing the at least partially opened cotton balls on a first large roller; rotating the first large roller rotating at a first speed past a first net to strip petals off the at least partially opened cotton balls; and capturing the first stripped cotton balls on a first small roller rotating at a second speed.
  • 16. The method according to claim 15 wherein the second speed is faster than the first speed.
  • 17. The method according to claim 15 further comprising the step of transporting the first stripped cotton ball to an output area.
  • 18. The method according to claim 15 further comprising the step of removing stripped petals from an area under the first net.
  • 19. The method according to claim 15 further comprising the step of sucking raw cotton balls from the hopper to the impacter.
  • 20. A cotton stripper for stripping petals from cotton balls, the cotton stripper comprising:a hopper; an impacter in process communication with the hopper; a first cleaning mechanism in process communication with the impacter; a cotton separator in process communication with the first cleaning mechanism, the cotton separator comprising; a first large roller encased in a licker-in wire rotating at a first speed; a first net located at a circumferential position adjacent to the first large roller; a first small roller encased in a doffer wire rotating at a second speed and adjacent the first large roller, wherein the second speed is faster than the first speed; a second large roller encased in a licker-in wire rotating at the first speed; a second net located at a circumferential position adjacent to the second large roller; a second small roller encased in a doffer wire rotating at the second speed and adjacent to the second large, a third large roller encased in a licker-in wire rotating at the first speed, and located below the first large roller and second large roller; a third net located at a circumferential position adjacent to the third large roller; a third small roller encased in doffer wire rotating at the second speed and adjacent the third large roller; and an output area in process communication with the cotton separator, wherein the impacter at least partially opens the raw cotton balls and removes some petals, the first cleaning mechanism discards petals that were removed by the impacter, the first large roller captures the at least partially opened raw cotton balls, the first net strips off petals, the first small roller takes the first stripped cotton balls from the first large roller, the second large roller captures the first stripped cotton balls, the second net strips off petals, the second small roller takes the second stripped cotton balls from the second large roller, the third large roller captures the first or second stripped cotton balls, the third net strips off petals, the third small roller takes the second or third stripped cotton balls from the third large roller and the output area stores second or third stripped cotton balls.
Priority Claims (1)
Number Date Country Kind
18/MUM/2001 Jan 2001 IN
RELATED APPLICATIONS

The present application claims priority to Indian Patent Application No. 18/MUM/2001 filed on Jan. 8, 2001.

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