This invention relates in general to processing fibrous materials, and in particular to a device for humidifying lint cotton and other fibrous materials and compressing the material to increase its density.
The present invention relates generally to a cotton conditioning device for adding moisture to lint cotton prior to the baling process. The device can be used with any existing cotton gin battery condenser. The device can be used as an attachment to receive a cotton batt from any existing battery condenser by attaching it intermediate the battery condenser and a slide configured to receive the humidified and compressed batt from the conditioning device. The device humidifies lint cotton by receiving a batt of lint cotton and compressing it at a nip point between two opposing, counter-rotating drums housed side-by-side with one drum being slightly elevated relative to the other. As the cotton lint is compressed between the two opposing drums, moist hot air is injected into one drum, through the perforated surface of the drum, through the batt being compressed and is drawn into the second drum.
Hot dry air is fed into the compartments of the drums when the corresponding segment of the surface is not carrying the cotton batt in order to keep dry the surface of the drums and clear the perforations of any lint that might have been retained on the surface.
It is well recognized that humidifying cotton lint prior to baling aids with the baling process by reducing the forces required to compress the bale. Also, there are multiple reasons that correct moisture levels are desirable for the spinning mills that use these bales. For example, cotton fibers with too low of a moisture content become brittle and are prone to breakage. There are currently four widely-used methods to add moisture to a cotton batt prior to baling. One common method, falling out of favor for its poor results, is simply to set up an atomized mister above the slide that moves the cotton batt to the baler, spraying water directly onto the surface of the cotton. The thicker the batt, the less desirable this method becomes. The moisture does not tend to migrate through the batt evenly, resulting in alternating layers of wet and dry cotton in the finished bales. When moisture is added in this way, it is very easy to add too much water to a bale, thus making it prone to damage from rotting. This method can also be deceitful since excess water weight can easily be added to a bale (cotton being sold by weight). Even if the right amount of moisture is added per unit volume of cotton, it is only useful if it is fairly evenly distributed throughout the bale. When a spray system is used on a thick batt, the layering effect described above can potentially create micro layers of moisture-damaged cotton and good cotton throughout a bale, thus rendering the entire bale useless.
A second method is described in U.S. Pat. No. 4,103,397, entitled “Lint Slide Grid Humidifier.” The device of this patent registration consists of a perforated lint slide which receives a batt of cotton from a battery condenser. As the batt is moved along the slide, hot moist air is allowed to slowly rise up through the bat along most of the length of the lint slide. Although this system is effective, it is inefficient because the rate of moisturization of the device cannot keep up with current capacity requirements. The capacity of a slide grid humidifier can be increased by adding length to the slide, but it is impractical to elongate slides further due to factory building height limitations. Furthermore, current batts are thicker than batts produced in the past and it is difficult to pass humid air through them uniformly by applying only a positive pressure on one side, resulting in an uneven distribution of moisture throughout the batt.
Another common method of humidifying lint cotton is shown in a variety of patents by A. L. Vandergriff. U.S. Pat. No.(s) 4,140,503, 4,999,881 and 5,381,587 are different versions of a cotton lint humidifying device having a drum with separated segments. U.S. Pat. No. 4,140,503 teaches a device which raises the moisture level of the cotton lint by passing it between sealing rollers. Moist or humid air is then supplied to the condenser chambers, raising the cotton lint to the desired moisture level.
Similarly, U.S. Pat. No. 4,999,881 uses a system of air chambers and conduits which transport dry heated air to certain metal surfaces within the condenser unit, increasing the temperature of surfaces and avoiding moisture build up as a means of condensate control.
U.S. Pat. No. 5,381,587 teaches a cotton gin lint condenser which rotates the batt through different segments of the housing. The housing has a lint inlet segment, a segment for adding moisture to the batt by passing it through warm humid air, a segment for doffing the batt from the drum, and a segment for removing moisture from the drum by rotating it through dry air. The warm dry air also warms the lint slide surface.
Another way to add moisture to cotton lint is taught in U.S. Pat. No. 6,314,618 entitled “Moisture Conditioner for Lint Cotton.” This device is different from prior devices because the steam roller is not a part of the cotton gin battery condenser but rather an add-on the device. The steam roller device may be incorporated at the top of the slide after the battery condenser. A continuous batt of cotton is passed between a stationary screen and a rotatable cylinder having a perforated surface. Hot humidified air is passed through the screen and batt, and is drawn into the cylinder.
It is an object of the present invention to provide a cotton conditioning device for adding moisture to lint cotton during the baling process.
Another object of the present invention is to provide a cotton conditioning device that further compresses the continuous cotton batt received from a battery condenser.
A further object of the present invention is to provide a cotton conditioning device which can be used with any existing cotton gin battery condenser.
Another object of the present invention is to provide a device which effectively and efficiently adds moisture to lint cotton during the baling process.
Another object of the present invention is to provide a cotton conditioning device which can be manufactured and sold at a reasonable price and added to existing cotton processing lines.
Accordingly, a presently preferred embodiment of the present invention provides a cotton gin conditioning device for adding moisture to lint cotton prior to the baling process. The conditioning device receives a continuous cotton batt from a cotton gin battery condenser that is fed between two opposing, counter-rotating drums. Hot moist air is drawn from a source into one drum and forced or drawn out of the perforated surface of the drum, through the batt as it is being compressed between the two drums, and into the other drum. The opposing drums are internally compartmented by a plurality of longitudinal staves, each compartment being covered by a corresponding segment of the perforated surface. Hot dry air is fed or drawn into the compartments of the drums when the corresponding segment of the surface is not carrying the cotton batt in order to dry the surface of the drum and clear the perforations of any lint that might have been retained on the surface.
The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which:
As illustrated in a schematic side view in
As best shown in
Returning to
Preferably, the stationary unit 30 is attached adjacent to the batt output opening 13 of a battery condenser 17 such that the continuous batt 11 is fed from the battery condenser 17 onto the lower drum 31 or the upper drum 61 proximate to the nip point or gap 14 between the lower drum 31 and the adjacent upper drum 61. Again, as best shown in
As shown in
The upper drum 61 is located within the heel portion 81 of the suspended unit 60 and, as shown, the curvature of mating surfaces 29 substantially follows the curvature of the exterior surface 63 of the upper drum 61.
The toe portion 82 of the suspended unit 60 houses a powered, rotatable doffing roller 83 on a shaft 78 running from the first and second sides 26, 27 of housing 23 that is substantially parallel to shaft 45 of the upper drum 61. Shaft 78 is adjustibly positionable on the first and second sides 26, 27 of the housing 23 such that the distance between the doffing roller 83 and the upper drum 61 may be varied by the user. The doffing roller 83 functions to remove any lint that accumulates on the perforated stainless steel exterior surface 63 of the upper drum 61. A plurality of replaceable flashings 85 extend from the exterior 84 of the doffing roller 83 along its longitudinal axis. The doffing roller 83 is rotated in the same direction as the upper drum 61 so that the flashings 85 of the doffing roller 83 sweep against the exterior surface 63 of the upper drum 61, thereby removing any lint that may have accumulated on the upper drum 61. As the flashings 85 are worn away from friction with the perforated surface 63 of the drum 61, the doffing roller 83 can be positioned nearer to the upper drum 61 so as to remain effective until the flashings 85 must be replaced. Preferably, the doffing roller 83 runs at a perimeter speed (or surface speed) slightly faster than the upper drum 61 such that in the event any excess lint is carried around on the surface 63 of the upper drum 61 after the batt would normally have been expected to have separated from the drum 61, the excess lint would be brushed off and thrown down to the lint slide 76 by the doffing roller 83.
The suspended unit 60 is suspended from a laterally transverse shaft 79 located toward the top of leg portion 80 of the housing 23. The shaft 79 is axially aligned with the upper drum 61. When suspended from shaft 79, the mating surfaces 29 of the suspended unit 61 contact or rest upon the mating surfaces 28 of the stationary unit 30.
The lower drum 31 and the upper drum 61 are positioned within their respective housings 22, 23 to form a nip point 14 between the exterior surface 33 of the lower drum 31 and the exterior surface 63 of the upper drum 61. At the nip point 14, when the mating surfaces 28, 29 of the housings 22, 23 are in mated position, the surfaces 33, 63 of the upper and lower drums 61, 31 face each other across a gap that is preferably about one quarter inch (0.63 cm) apart, but not more than about one inch (2.54 cm) apart, to facilitate the intake of the batt 11. In a preferred embodiment, the upper drum 61 is positioned slightly above the lower drum 31 as illustrated in
As a continuous batt 11 is fed into the nip point 14, the drums 31, 61 rotate in opposite directions away from the battery condenser 17. Friction of the batt 11 with the texturized, perforated exterior surfaces 33, 63 of the rotating drums 31, 61 at and about the nip point 14 serves to continually advance the batt 11 through the conditioning device 10. A continuous batt 11 exiting a battery condenser 17 is typically four to fifteen inches thick and is compressed as it traverses the nip point 14. The perimeter speed (or surface speed) of drums 31, 61 are set at approximately the same perimeter speed of the battery condenser drum (not shown) to prevent breakage of the batt.
The shaft 79 acts as a pivot point for the suspended unit 60 and upper drum 61, allowing the suspended unit 60 and upper drum 61 to be pushed away from the stationary unit 30 and lower drum 31 as a batt 11 passes between the lower drum 31 and the upper drum 61. Even though it is pivotedly engaged against the stationary unit 30, the weight of the suspended unit 60 will generally provide sufficient compressive force to the batt 11 at the nip point 14 so that the suspended unit 60 does not pivot, or pivots only nominally (generally less than 6 to 8 inches) during the ordinary course of operation. In order to ensure that the proper amount of compression is achieved, one or more pneumatic pistons (not shown) may be attached to the toe portion of the housing 23, thereby providing a means for controlling movement of the suspended unit 60 and its drum 61 relative to the stationary unit 30 and its drum 31. In order to facilitate cleaning of the conditioning device 10, it has been found that it is preferable to provide a leverage point above the suspended unit 60, such as arm 19 and eyelet 20. Using the leverage point and a hook or loop 21 on the toe portion of the housing 23, a cable or chain (not shown) can be connected to winch the suspended unit 60 away from the stationary unit 30 for easy access, such as for cleaning.
The exterior surface 33 of drum 31 comprises a perforated surface having a multiplicity of perforations, preferably distributed uniformly about the entire surface 33, which is preferably stainless steel. The exterior surface 63 of upper drum 61 is similarly perforated. Preferably the exterior surfaces 33, 63 are not smooth, but rather has a slight texture to assist in carrying the cotton lint batt 11 along with the rotation of the drum 31, 61. Finally, in one embodiment, the exterior perforated surfaces 33, 63 of the drums 31, 61 comprise a removable perforated stainless steel sheath attached to the staves 36, 66 so that it can be removed for cleaning or replacement.
As best shown in
As shown in
At least one of, but preferably both the first and second sides 24, 25 of the housing 22 are pierced by an anterior passage 37 and a posterior passage 41. The anterior passage 37 is shaped to open into the lower drum 31 between the core 32 and the exterior surface 33 about and before the nip point 14 (not shown in
Similarly, but illustrated only schematically in
In a preferred embodiment of the present invention, it has been found advantageous to provide a means for varying the size of the anterior and posterior passages 37, 41, 67, 69 of both the lower and upper drums 31, 61. Varying the size of the passages 37, 41, 67, 69 allows for the airflow to be more precisely directed into the compartments 35, 65 of the drums 31, 61 as well as increasing and decreasing the rate of the airflow. For example, by directing the flow of air primarily into the compartments 35, 36 as they rotate towards the nip point 14, the flow of hot moist air can be directed primarily through the batt 11 before it is compressed by the nip point 11, thereby increasing the efficiency of the dispersion of moisture throughout the width of the batt 11.
Returning, then, to
The preferred number of flashings 38, 39 used in each set and their positioning relative to each other depend upon several variables such as the radius of the drum 31, the number of staves 36, length of flashings 38, 39 and the anticipated rotational velocity of the drum 31. The number and positioning of rows of flashings 38, 39 within each set should be varied as necessary in order to minimize or prevent altogether the instances where a continuous channel from one air chamber 107 to the other 108 is created as the drum 31 rotates.
The housing 22 further comprises an exit passage 56 through the housing 22 into the posterior air chamber 108. Ducting 54 may be connected to the exit passage 56.
Referring now to
When the complete conditioning device 10 is formed, the three airflow channels illustrated schematically by arrows X, Y and Z in
A primary conditioning channel (illustrated by arrows X1-X6) is formed to direct hot, moist air through the batt 11 as it passes about the nip point 14 between the counter-rotating lower drum 31 and upper drum 61. Specifically, air flowing through the primary conditioning channel is blown or drawn, or both, but preferably at least drawn, from a hot, moist air source (not shown) through ducting 50, 51, 42 (arrows X1 and X2), through anterior passage 37 (arrows X3) into one or more of compartments 35 of the lower drum 31 as said compartments rotate past anterior passage 37, through the perforated surface 33 of the lower drum 31 (arrows X4) through the perforated surface 63 of the upper drum 61, into one or more of compartments 65 of the upper drum 61 as said compartments rotate past anterior passage 67, through anterior passage 67 (arrow X5) and on through ducting 73, 72 (arrow X6), eventually to a bank of cyclones (not shown) to remove particulate matter from the air, and eventually to an exhaust (not shown). Preferably, the negative air pressure generated by one or more pull fans at the exhaust end of the primary conditioning channel is greater than the positive air pressure generated by any pushing fans that push or inject air into the primary conditioning channel to ensure the proper draw or pressure gradient of hot, moist air across the batt 11 through the primary conditioning channel.
Due to the rotation of the drums 31, 61, each open-ended compartment 35, 65 only periodically comprises a portion of the primary conditioning channel as it rotates past (or adjacent to) the anterior passage 37, 67. When a portion of an compartment 35, 65 is beside an anterior passage 37, 67, a continuous channel is opened allowing the flow of air described above. When a portion of a compartment 35, 65 is not beside an anterior passage 37, 67, there is no draw of air through the compartment 35, 65 unless the compartment 35, 65 is beside the posterior passage 41, 69 of that respective drum 31, 61, at which point the compartment 35, 65 forms a portion of one of the other two airflow channels of the conditioning device 10 as described below.
Thus it can be seen that due to the positioning of the anterior passages 37, 67 about, and preferably tending towards the side of the nip point 14 where the batt 11 is approaching the nip point 14 before being compressed, when a batt 11 is moving towards and through the nip point 14 between counter-rotating drums 31 and 61, the hot, moist air is drawn through the batt 11 from the compartments 35 of the lower drum 31 and into the compartments 65 of the upper drum 61, thereby adding moisture in a substantially uniform manner to the entire width and breadth of the batt 11. The draw of air through the anterior passage 67 of the upper drum 61 must be of sufficient strength to create a draw through the anterior passage 37 of the lower drum 31 despite the potential leakage of some air into the anterior air chamber 107. To the extent that hot, moist air might flow into the anterior air chamber 107 from the compartments 35 of the lower drum 31 prior to being drawn through the batt 11 and into the compartments 65 of the upper drum 61, the anterior air chamber 107 may be considered a portion of the primary conditioning channel.
Using the cotton conditioning device 10 of the present invention, one is able to control the moisture content of the batt 11 by adjusting the amount of moisture in the flow of hot, moist air at its source, or by adjusting the speed at which the batt 11 transverses the conditioning device 10, or by adjusting the pressure gradient or speed at which the hot moist air moves through the primary conditioning channel. For example, the moisture content of the hot moist air may need to be adjusted to account for the amount of moisture already existing in the air of that particular locality and/or the amount of moisture desired in the batt 11. One or more conventional sensing devices can be added to detect the moisture content of the lint cotton either before or after passing through the conditioning device 10 and alert the user to make necessary adjustments. This adjustment could also be made automatically with electronic controls connected to the sensing devices.
In a preferred embodiment, it has been found useful to utilize the hot, moist air traveling to the anterior passage 37 to heat the underside of slide 76 before drawing it through ducting 50, 51 and 42 to anterior passage 37.
Because of the moisture being pulled through the drums 31, 61 as part of the primary conditioning channel, in order to avoid the accumulation of condensation and lint on the exterior perforated surfaces 33, 63, cores 32, 62 and staves 36, 66 of the drums 31, 61, it is desirable to dry these surfaces during operation. The other two airflow channels (illustrated by arrows Y and Z) carry hot, dry air through the conditioning device 10 to dry the exterior perforated surfaces 33, 63, cores 32, 62 and staves 36, 66 of the drums 31, 61.
A first drying channel (illustrated by arrows Y1-Y4) is formed to direct hot, dry air along a pressure gradient through the posterior side of drum 31. Specifically, air flowing through the first drying channel is blown or drawn, or both, but preferably at least drawn, from a hot, dry air source (not shown) through posterior duct 43 (arrow Y1), through posterior passage 41 (arrows Y2) into one or more of compartments 35 of the lower drum 31 as said compartments rotate past posterior passage 41, through the perforated surface 33 of the lower drum 31 into posterior air chamber 108 (arrows Y3) and on through exit duct 56 (arrow Y4) and any associated ducting 54.
Due to the rotation of the drum 31, each compartment 35 only periodically comprises a portion of the first drying channel as it rotates past the posterior passage 41. When a portion of a compartment 35 is beside the posterior passage 41, a continuous channel is opened allowing the flow of air described above.
Though it is possible that the direction of the air flow through the first drying channel might be reversed from the flow just described, this is less preferable because the action of air blowing in through the perforated surface 33 would tend to carry lent into the compartments 35 of the drum 31 where it might accumulate, resulting in an accelerated need to clean the conditioning device 10. Conversely, by using the preferred airflow through the first drying channel, air blowing from inside the compartments 35 out through the perforated surface 33 assists in keeping the perforations from becoming clogged with lint.
A second drying channel (illustrated by arrows Z1-Z4) is formed to direct hot, dry through the posterior side of drum 61 in order to dry the exterior perforated surface 63, core 62, and staves 66 of drum 61. Specifically, air flowing through the second drying channel is blown or drawn, or both, but preferably at least blown, from a hot, dry air source (not shown) through posterior duct 70 (arrow Z1), through ducting 71 (arrow Z2), then through posterior passage 69 (arrow Z3) of upper drum 61 into one or more of compartments 65 of the upper drum 61 as said compartments 65 rotate past posterior passage 69, through and away from the perforated surface 63 of drum 61. In the illustrated preferred embodiment, the posterior side of upper drum 61 comprises an unsealed compartment that is open to the atmosphere, allowing the hot, dry air to be pushed away out of any available opening, such as along the lines illustrated as arrows Z4. If desired, additional exhaust ducting or hooding (not shown) could be added to carry the air away from the second drying channel after it exits the perforated surface 63 of drum 61.
Due to the rotation of the drum 61, each open-ended compartment 65 only periodically comprises a portion of the second drying channel as it rotates past the posterior passage 69. When a portion of a compartment 65 is beside the posterior passage 69, a continuous channel is opened, allowing the flow of air described above.
Where each of the first drying channel and second drying channel ultimately exits or is vented to the atmosphere, it may also be desirable to employ any of the known means to control condensation that may form on surfaces as the hot, dry air carries moisture away from the drums 31, 61.
Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to the preferred embodiment of the invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.
Number | Name | Date | Kind |
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4103397 | Jackson | Aug 1978 | A |
4140503 | Vandergriff | Feb 1979 | A |
4999881 | Vandergriff et al. | Mar 1991 | A |
5155886 | Schrader et al. | Oct 1992 | A |
5199133 | Burton | Apr 1993 | A |
5381587 | Vandergriff | Jan 1995 | A |
6314618 | Mehner et al. | Nov 2001 | B1 |
6698066 | Latham | Mar 2004 | B2 |
Number | Date | Country | |
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20080005869 A1 | Jan 2008 | US |