US 3505701 A
Description (OCR text may contain errors)
April 14, 1970 E. w. KEIL LIQUID REMovING MACHINE Original Filed Nov. 14, -1965 RN N ATTOR NEY Patented Apr. 14, 1970 3,505,701 LIQUID REMVING MACHINE Edward W. Keil, Manchester, Mo., assignor to Total Systems Concept, Inc., St. Louis, Mo., a corporation of Missouri Continuation of application Ser. No. 594,034, Nov.. 14, 1966. This application July 12, 1968, Ser. No. 751,664 Int. Cl. F26b 13/14 U.S. Cl. 15-102 2 Claims ABSTRACT F THE DISCLOSURE A machine adapted for removing liquid from sheet material for substantial drying thereof incorporating a pair of vertically aligned, cooperating rollers formed oi resilient material, each roller having oil tanned leather disposed about its peripheral surface for contacting the material to be treated to remove moisture contained on and in such material, there being means for continuously supplying liquid to the surface of said leather for enhancing the absorptive qualities thereof.
This is a continuation of application Ser No. 594,034, filed Nov. 14, 1966, for a liquid removing machine and now abandoned.
This invention relates in general to apparatus for drying materials and, more particularly, to a machine for the elfective removal of liquid from sheet material, as received thereon from rinsing or other treating operations.
Heretofore, numerous expedients have been attempted for the purpose of substantially drying, or of liquid re moval from, sheet material which has been previously subjected to wetting action as by treatment bathsl Among such expedients has `been the subjection of the sheet material to pressure between heated surfaces, or between surfaces, such as rolls, having inadequate absorbent coverings. Such coverings have included fabric having a piled surface, as velours and felt; cotton cloth; rubberized material; and the like. However, none of these efforts have proven successful with economic moisture withdrawl, so that the object to be dried must be subjected to a further operation as, for example, a relatively lengthy oven treatment.
The inadequacy of heretofore known means for liquid removal of materials has been particularly manifested with respect to treating plastic sheet material, as of the rigid type, such as bases for printed circuits made, for example, from paperJbased phenolics, glass cloth, reinforced epoxies, laminated phenolics, etc., including metal clad laminates, such as, particularly, those having copper applied thereon as completed printed circuits, as well as exible materials, as, for instance utilized in photographic films and the like. Such materials are ordinarily subjected to water rinsing baths and the problem of rapid drying of the surfaces thereof is one of great criticality since the speed of production is dependent thereon. With copper clad laminates failure to effect complete, rapid drying has conduced to the undersira'ble result of the oxidation of the copper.
Therefore, it is an object of the present invention to provide a machine for effecting substantial liquid removal from the surfaces of sheet material.
It is a further object of the present invention to provide a machine of the character stated `which incorporates a novel liquid withdrawing expedient comprising a relatively loosely interwoven animal skin or skin-simulative material which has proven in practice to have the capacity for withdrawing all but a most limited amount of liquid on a contacted surface, such remaining amount being in the order of approximately 2% or less.
It is a further object of the present invention to provide a drying apparatus of the type stated which may be easily interjected into an assembly line operation for automatic action thereby obviating the costly services of operating personnel and which brings about marked economies in overall production.
It is a still further object of the present invention to provide a drying apparatus which is most economically manufactured; which comprises a marked simplicity of parts, being devoid 0f any intricate complex components, so as to be resistant to breakdown; and which is, therefore, reliable and durable in usage.
Other objects and details of the present invention will be apparent from the following description when read in connection with the accompanying drawing (one sheet) wherein- FIGURE l is a top plan view of a liquid removing machine constructed in accordance with and embodying the present invention.
FIGURE 2 is a vertical, longitudinal, sectional view taken on line 2-2 of FIGURE l.
FIGURE 3 is a vertical transverse sectional view taken on line 3 3 of FIGURE 2.
FIGURE 4 is a vertical, longitudinal, sectional view taken on line 4-4 of FIGURE l.
Referring now by reference characters to the drawing which illustrates the preferred embodiment of the present invention, A generally designates a liquid removing machine which essentially comprises three fundamental components, namely, a feed conveyor 1, a liquidremoving section 2, and a discharge conveyor 3. By ymeans presently to be described, the aforesaid cornponents integrate into a synchronized unit for effecting rapid travel of liquidladen sheet material to, and through, liquid removing section 2 for delivery of same therefrom to subsequent treatment units in the particular assembly line.
Said feed and discharge conveyor sections 1, 3 being symmetrical, are of like construction, as each embodies a frame 4 comprising a pair of spaced-apart, elongated, parallel side members 5, 6 each having top flanges 5', 6', respectively. Journaled at their ends within said side members 5, 6 is a plurality of friction rollers 7, there being a relatively narrow, endless belt 8 extending about the central portion of said rollers 7 for frictionally transmitting motion thereto through the rotation of a drive roller 9 about which one end portion of said belt 8 is trained. The drive roller 9 of each conveyor 1, 3 is carried on a shaft 10 which is journaled at its ends within bearings 11, 11' supported on side plates 12, 12', respectively, which plates are suitably interengaged with the frames 4 of each conveyor 1, 3 and are located laterally outwardly and intermediate the same. Inwardly of the related bearings 11', each shaft 10 mounts a sprocket 13 about which is engaged one end of a drive chain 14, the other end portion of which engages a sprocket 15 carried on the shaft 16 of the respectively immediately adjacent one of a pair of drying rollers 17, 18. Shafts 16, which are axially parallel to friction rollers 7, are journaled in bearings 19, 19' mounted on side plates 12, 12', respectively.
Shafts 16 are operatively interconnected by a drive chain 20 which, in its upper portion, engages sprockets 21 xed on each shaft 16 and in its lower portion is suitably engaged to the drive shaft 22 of a prime mover M (FIGURE 3).
Upon energization of prime mover M, `by means of the motion transmitting system above described, said shafts 16 will be caused to rotate in a clockwise direction as viewed in FIGURE 2 whereby drive chains 14 will cause shafts 10, mounting drive rollers 9, to rotate similarly in a clockwise direction, as seen in FIGURE 2,
so that the endless belt 8 of each conveyor section 1, 3 will move in the same direction (as shown by arrows in FIGURE l) resulting in friction rollers 7 of conveyor 1 causing delivery of sheet material thereon to liquid removing section 2, and in ythe friction rollers 7 of discharge conveyor 3 moving the treated material rapidly away from the said liquid removing section 2.
Each roller 17, 18, is surrounded throughout its peripheral surface with a liquid receiving material or covering c which may be adhered to the roller surface by requisite cementitious agents. The peculiar nature of covering c which is critical to the operation of machine A, will be described more fully hereinbelow. Provided for cooperation with each of said rollers 17, 18 is a companion roller 23, 24, respectively, of like diameter and axial extent; said rollers 23, 24 being disposed in vertically aligned, axially parallel relationship with the related rollers 17, 18, respectively. Each of said rollers 23, 24 is mounted upon a shaft 23', 24', respectively, which shafts 23', 24 are journaled at their ends in blocks 25. Said yblocks 25 are mounted for vertical slideable movement within slideways (not shown) formed in frame elements 26, 26 which are supported by brackets 27 engaged upon the inner end portion of flanges 5', 6 of side members 5, 6 of frames 4. Adjustment screws 28 are associated with each block 25 for controlling lthe vertical disposition of same within such slideways, in a manner well known. Each of said rollers 23, 24 is similarly encased in a covering c.
Although in the drawing rollers 17, 18 are illustrated as being of slightly increased diameter relative to drive rollers 9, it is to be recognized that the peripheral speed of said rollers 17, 18 must be the same as that of rollers 9 so that suitable motion transmitting means, of conventional character, must be utilized for effecting such relationship. Obviously, this aim could as easily be accomplished by making drive rollers 9 of the same diameter as rollers 17, 18.
The body of each of said rollers 17, 18, 23, 24 are constituted of preferably material of limited resiliency, such as, desirably rubber having a durometer hardness of 60 to 70. The character and operation of rollers 17, 18, 23, 24 will be more fully described hereinbelow.
Presented upwardly of each roller 23, 24 is a liquid discharge device 29 connected to a source of liquid (not shown), said device being, for example, a pipe 29 having a plurality of spaced-apart orifices 3:04 for emission of the liquid, preferably the same as that being removed from the work, for continuous wetting of covering c of rollers 23, 24 for purposes presently to be described.
Covering c, which encases the resilient underlying body of drying rollers 17, 18 and 23, 24 is constituted of oil tanned leather as best exemplified by leathers formed from the flesh layers of goat and sheep skins. The sheep, goat, or lamb skins, for example, after being subjected to the customary preparatory treatment are split for separating the grain from the flesh layer, which is the inner side of the skin. Such esh layer is t-hen tanned or preserved by the use of certain drying oils, for example, cod oil, linseed oil, and other well known oils which are worked into the skins and allowed to oxidize and react, thus becoming fixed. Probably the foremost type of leather so formed is that well known as chamois. After the oil-tanning process is completed, the leather, such as chamois is washed with warm alkalized water and hydraulically pressed to remove excess oil. Further washing, buing and drying complete the requisite steps. Leathers so formed and, particularly chamois, have demonstrated an unusual capacity for liquid absorption and to such an extent that sheet materials presented to the so covered drying rollers of the present invention do not require subsequent drying treatment, as for instance, by subjection to la drying oven. The affinity of covering c for moisture is not entirely understood although it appears conceivable that the particular peculiar texture of such leathers may be one of the reasons therefore in that the fibers are extremely thin and not closely interwoven, tending to run parallel to the skin surface which makes for looseness of texture. It has been discovered that when covering c is in a damp or moistured state, its capacity for absorbing liquid is greater than when in a completely dry or saturated condition. This phenomenon suggests that this usual capability results from enhanced capillary attraction. In view of this particular property, liquid will be continuously discharged from orifices 30 of liquid discharge device 29 to maintain covering c of rollers 23, 24 in a moistened state; such liquid being easily transferred from rollers 23, 24 to their cooperating rollers 17, 18. As will be shown hereinbelow, only one set of rollers, either 17, 23 or 18, 24, are utilized at one time so that liquid discharge device 29 will Ibe directed so that the momentarily active rollers 23, 24 will be subjected to wetting action.
In actual usage, only one set of drying rollers, either 17, 23 or 18, 24 is necessary for liquid removal. The presentation of two sets of rollers is designed to convey the desirability of having a reserve set available so that if one set of rollers become damaged or worn, the same may be separated so that sheet material may vbe delivered to the other set of rollers without loss of time. Thus, it is to be noted that only one set of drying rollers is necessary.
In operation, the rollers of the presently effective set, whether 17, 23 or 18, 24, are in contact at all times, as indicated at m and being of predetermined pressure so that the contacting areas will be subjected tomutual wringing action causing removal of excess liquid from the contacting coverings c with such liquid flowing relatively rearwardly in the direction of the ingress side, as indicated at i, of said rollers with the exit side, as indicated at e, being moist or damp. The pressure applied to said cooperating rollers may be effected in any desired manner in accordance with known tec-hniques, such as, for instance, by suitable tightening of screws 28 or by the use of coil springs for urging the upper rollers downwardly, or by pneumatic pressure, such as through the interposition of pneumatic cylinders. But it is apparent that the mutual contacting of the cooperating rollers is critical for the effective operation of the present invention to make certain that coverings c are maintained in a moistened condition for maximum removal of liquid from the work w presented thereto.
It is apparent that the thickness of the cooperating rollers, as well as the amount of pressure applied thereon, are factors to -be determined by the thickness of the work w to be presented for liquid removal. With the work w, as at material, the cooperating rollers will necessarily be caused to give so as to allow the work to pass therebetween. Thus, the resiliency of the rubber of the body of said rollers, as well as pressure supplying force, whether it be springs, pneumatic in nature, or the like, must be taken into account so as to accommodate the particular thickness of work w and yet allow for maximum effective liquid removal. As an example only, with work w ranging from the thickness of a film to 1/s inch, as in plastic sheets, the cooperating rollers may have a diameter of approximately 2% inches, which thickness will be adequate to provide the necessary yieldability as with rubber of 60 to 70 durometer hardness to allow for passage of the work w therebetween. With wo-rk w of greater thickness, it is apparent that rollers of relatively increased diameter would have to be utilized and with suitable means being presented so that the work would not be caused to assume a difficult angle in presentation to the rollers. Accordingly, with work w of the thickness above specified, namely, with lm to 1A; inch, the resiliency of t-he material of the rollers will be adequate for accommodation purposes. However, with thicker work, the yieldability of the pressure providing means must necessarily assist in according the necessary resiliency for movement of the work w between said rollers.
Thus, liquid laden sheet material is delivered by the conveyor section to the operating set of drying rollers. As the sheet material moves through the ingress side of said rollers, it will be subjected to a squeegee action by said rollers which thus will tend to brush or sweep liquid on said material relatively rearwardly thereof. As the material moves into the exit side of said rollers, it will be subjected to an absorbing action with liquid thereon being drawn from the material by the moistened portions of the rollers coverings c. Thus, said rollers cause a sequential squeegee and wringing action upon the sheet material which, in practice, has been shown to be freed of between 98 and 99 percent of the liquid upon its surfaces. This substantial drying obviates the need for any further drying treatment for the sheet material since the limited (approximately 1%) remaining, minor amount is so evenly and finely spread across such surfaces that the same will evaporate in the ambient atmosphere.
The present invention has been found markedly eflicient in the drying of rigid plates as formed from various types of resins used as bases for printed circuits. Prior to the present invention there has been a serious problem in the industry for the drying of such plates after they have been subjected to a rinsing bath. Elongated drying ovens of the infra-red type have been used for this purpose but at substantial expense, both in time and money, and without consistent results. Such plates normally are -provided with a plurality of openings in which such liquid tends to collect. The withdrawal of such liquid has also proved quite difficult with devices heretofore used. However, the present invention has proved readily adapted for Withdrawal of liquid, both from the exposed surfaces, as well as from the openings.
The machine of the present invention conduces to high speed, rapid drying of sheet materials of all types, whether rigid, semi-rigid, or fully exible, with attendant economies in production. It is obvious that machines of the type herein described may be readily integrated into existing assembly lines without requiring costly modifications or expenditures. Furthermore, the critical nature of covering c has obviated the necessity of complex equipment which has not performed to the requisite extent, far from approaching that achieved by this invention. It is recognized that with present day technology, it is conceivable that synthetic or artificial leathers may be developed having properties corresponding to those of the oiled tanned leather, such as chamois, and such are definitely contemplated Within the scope of the present invention.
What is claimed is:
1. A machine for liquid removal from sheet material comprising a frame, a pair of rollers mounted on said frame, said rollers being in vertically aligned, axially parallel relationship, means for feeding liquid laden sheet material for drying to said rollers, means for effecting rotation of said rollers in the same direction as the direction of feed of said feeding means, means for receiving the now dried sheet material from said rollers after passage therethrough, an oil tanned leather being formed from the flesh layers of animal skins wherein the fibers of such leathers are relatively thin, tending to run parallel to the skin surface and not being closely interwoven, coveringly disposed about the peripheral surface of each of said rollers, said rollers being fabricated from resilient material having a durometer hardness in the range of to 70, pressure exerting means for urging said rollers into mutual contactive relationship so as to present said leather coverings into forceful engagement with each other when said machine is inoperative and with opposite sides of sheet material fed therebetween when said machine is operative, whereby said sheet material in the initial portion of its pass between said rollers will be subjected to a squeegee action and during the latter portion of its pass therebetween will be subjected to a moisture absorbing action by said leather coverings, said rollers being fabricated of material having adequate yieldability so as to permit passage of the work therebetween, and means for continuously delivering liquid to the surface of said oil tanned leather covering the surfaces of each of said rollers for enhancing the absorptive character thereof.
2. A machine for liquid removal from sheet material as defined in claim 1 and further characterized by said oil tanned leather being chamois.
References Cited UNITED STATES PATENTS 352,986 11/1886 Wakely 15-102 582,952 5/1897 Roberts 15-4 1,199,424 9/1916 Robinson 15-100 1,487,375 3/1924 Fuchs 15-100 1,607,417 11/1926 Wescott 15-100 2,142,538 1/1939 Tondreau 15-100y H WALTER A. sonni-:1., Primary Examiner L. G. MACHLIN, Assistant Examiner U.S. Cl. X.R.
29-132; 34--12l; 68-262; 1GO-121