US 3736903 A
A coating device for coating generally cylindrical articles such as tampons. The device includes a pair of discs rotatable through a bath of coating material in a direction to present the discs with coating material spread thereon to a line of continuously advancing rotatably supported tampons. The tampons engage and pass between inner faces of the discs. The lubricant is one which aids tampon insertion by a user.
Description (OCR text may contain errors)
[ 1 June 5, 1973 United States Patent 1191 Townsend l18/DIG 9 18/227 X Diehl et a1. 18/503 X 2,642,835 6/1953 2651,288 9/1953 Reigh 2,740,375 4 1956 A. Townsend, Oshkosh,
Assignee: Kimberly-Clark Corporation, Nee- Primary [hammer-John McIntosh T L Damn P m AM m N F I! 0 TA m AR 6 on m CA.l w B Attorney-Daniel J. Hanlon, Jr., William D. Herrick and Raymond J. Miller nah, Wis.
 Filed: Dec. 21, 1970  ABSTRACT A coating device for coating generally cylindrical articles such as tampons. The device includes a pair of discs rotatable through a bath of coating material in a direction to present the discs with coating material spread thereon to a line of continuously advancing rotatably supported tampons. The tampons engage Appl. No.: 100,215
52 us. 01. ...................118/218, 118/227, 118/239 51 1m.1/02  Field ofSearch......................118/227,228,218,
118/232, 233, 239, 224, DIG. 9; 156/578;
and pass between inner faces of the discs. The lubricant is one which aids tampon insertion by a user.
 References Cited UNITED STATES PATENTS 2,638,072 5 1953 l8/DIG. 9 3 Claims, 4 Drawing Figures COATING INLET H O INLET COATING DRAIN PATENTEDJUH 5 I975 SHEET 1 or 3 COATING DRAIN PATENTED JUN 5 I975 SHEET 2 BF 3 FIG.
PATENTEU JUH 5 I975 SHEET 3 UF 3 COATING APPLICATOR ARRANGEMENT BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a new device and method for coating generally cylindrical articles such as tampons with a lubricating material. In the operation of the new device the tampons are guided in succession between opposed discs. The discs carry coating or lubricating material from a suitable pond to the moving tampons. The discs also are relatively movable toward each other axially to engage the tampons on the outer peripheral extremities of the discs. The discs are yieldable, at least in part, and resiliently engage the tampons. The yieldabl'e nature of the discs provides for intimate engagement with the tampons even though the latter may not be fully rounded or may have become somewhat flattened in the course of their production.
The invention will be more fully understood by reference to the following detailed description directed to a specific and preferred embodiment of the apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view partially in section and with parts broken away illustrating a coating device in accordance with the invention;
FIG. 2 is an elevational view partially in section and with parts broken away illustrating in solid line the operating position of the coating device and in dash line an inoperative position;
FIG. 3 is a fragmentary and perspective view of a device having specific means for effecting rotation of the article to be coated during the coating operation; and
FIG. 4 is an elevational view of parts broken away illustrating one method of mounting an article for rotation during the coating operation.
Referring now to the drawings, the numeral 1 designates a base having an upstanding side support 2 and a top 3. A carriage is generally indicated by the numeral 4 and includes a platform 5 having depending bearing blocks 6 journalling wheels 7. The wheels 7 support the platform 5 for movement in a rectilinear direction as is generally indicated by the relationship of the solid line structure and the dash line structure of FIG. 2. The wheels are carried by V-shaped tracks 8.
Referring now particularly to FIG. 2, an upstanding ear 9 supports one end of a fluid (air) cylinder 10 having a piston rod 11 and a connecting element 12 journalling the air cylinder to depending ear 13. The depending ear 13 is secured to the platform 5. Accordingly, actuation of the air cylinder 10 to move the connecting element 12 and the depending ear 13 from the solid line position to the dotted line position serves to move the carriage 5 and the equipment mounted thereon.
The numeral 14 designates a pair of spaced vertical supports mounted on the carriage 5. Bearings 15 on each of the supports provide for the rotatable mounting of an elongated hollow spindle 16 which threadedly receives at one end a holder 17. The shaft 18 extending coaxial with the spindle 16 is supported in linear bearings to allow axial movement of shaft 18 relative to the spindle 16. The pin 20 projecting in slot 21 and carried on shaft 18 transmits rotational force between spindle l6 and shaft 18 so that spindle and shaft rotate together.
Spring 22 confined between cap 23 and the spindle and disposed around the left hand end (FIG. 2) of shaft 18 continuously urges the cap 23 and shaft 18 leftwardly. A knob 24 carried on pivot arm 25 is arranged to engage the outer side of cap 23. The knob 26 on the opposite end of arm 25 is engaged by a stop 27 and serves to maintain the knob 24, cap 23 and shaft I8 in the operative solid line position illustrated in FIG. 2. The pivot arm 25 is journalled for free movement between the arms of fork 28 which is itself carried by depending side support 2a. As clearly illustrated in FIG. 2, when air cylinder 10 is activated to move the platform 5 from the solid line to the dash line position, the stop 27 engages the knob 26, causing the oppositely pivoted knob 24 to bias the cap 23 against the action of spring 22 and to urge shaft 18 to the dash line posit1on.
The holder 17 carries a flexible disc 29, and a second flexible disc 30 is carried on holder 31 which is itself threadedly received on the end of shaft 18. The opposite inner faces 29a,30a of the discs on their outer peripheral portions are arranged to engage therebetween the article to be coated. The faces 29a,30a are preferably planar and extend in parallel planes. For this purpose the outer peripheral portions of the flexible discs are substantially unsupported, the holder 17 and holder 31 extending from the central disc portions radially only partially outwardly. This arrangement permits resilient engagement of the discs with the article to be coated, and minimizes the effect of irregularities which may occur in the cylindrical tampon.
The device may be placed in the inoperative position to aid the making of apparatus changes without significant loss of coating material.
Referring now to FIG. 2, a pulley 32 supports V belt 33, and V belt 33 is driven by variable speed pulley 34. Motive power is supplied to the pulley 34 through gear box 35 from electric motor 36. Direction of the rotation of the belt 33 and the pulleys is indicated by the arrows in FIG. I. Pulley 32 is itself keyed to the spindle 16 by key 32a (FIG. 2). Numeral 37 indicates a tank for coating material. An inlet 38 is provided for the coating composition and a coating drain is indicated at 39. Numeral 40 identifies a jacket which is adapted to retain heated water and has for this purpose a water inlet 41 and water outlet 42. Heated water may be continuously fed through the jacket to maintain coating material in the tank 37 at a desired temperature.
In the drawings a fragment of a traveling chain 43 is shown. Rollers 44 and angle irons as at 45 are carried by the chain. Each angle iron 45 supports a mounting 46 which supports a holder 47 for a tampon 48. The holder 47 (FIG. 3) is engaged by a round belt 49 which passes over guide pulleys 50, driven pulley 51 and drive pulley 52. The power transmission belt is supported independently of the article carrying guide means. It engages the holder 47 and serves to positively maintain the tampons in rotation during the application of coating material fed by the rotation of the discs in the tank 37 of coating material. The coating feed is upwardly on the inner surfaces of the discs to the traveling line of tampons as is most clearly shown in FIG. 1.
One particular form of holder suitable for the purpose of adequately retaining the tampon is illustrated in FIG. 4. Therein the upper stationary elongated cylindrical housing 53 is retained by the mounting 46 and itself retains through bearings 54 holder 47. Holder 47 and housing 53 are open axially to permit the stick 48a of the particular type of tampon illustrated to pass upwardly into the retaining structure. In some instances, as'is specifically illustrated in FIG. 3, the stick 48a may protrude above the holder.
1 have found that a suitable lubricant for the purpose of coating tampons is polyethylene glycol of a molecular weight in excess of about 400. Other lubricants such as waxes serve the purpose. The coating material should be maintained at a temperature suitable to its application and at aviscosity such that it coats rather than penetrates the tampon body structure. Commonly, such tampon body structure is composed of a blend of rayon and cotton fibers although the fiber composition is not critical to the practice of this inven tion.
In practical application the tampons, in closely spaced array, are carried by the chain at a constant speed of about fpm through the discs. For a given chain speed, the faster the discs are rotated and the more coating is presented per unit time to the tampons and the larger is the coating thickness deposited.
The rotational speed of the tampons affects coating uniformity and appearance as well as coating distribution. The more viscous the coating material at time of coating applica-tion, the greater usually is the applied coat weight.
As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that I do not limit myself to the specific embodiments thereof except as defined in the appended claims.
1. In a'coating device a base structure, a platform movably supported on said base structure, mechanism on said platform for coating a plurality of generally cylindrical surfaces moving in succession, said mechanism including a pair of spaced rotatable discs, guide means for directing articles having the cylindrical surfaces in a linear path between the discs and concentric shaft means each supporting a rotatable disc and each supported for rotation with the other, means, independent of said mechanism, for moving the platform relative to said base, and means supported by said base engaged by the platform in its movement to urge one concentric shaft means axially of the other.
2. A coating device according to claim 1 wherein said concentric shaft means have means biasing the shafts toward a closed position of the discs.
3. A coating device according to claim 1 wherein track means movably support the platform on the said base structure.