Umted States Patent [1 1 [111 Somerville Dec. 4, 1973 ELASTOMERIC FEED ROLLER [75] Inventor: Richard C. Somerville, Dover, Mass. ABSTRACT [73] Assigneez Globe Rubber works Inc. M An elastomeric replacement feed roller adapted to be Quincy Mass secured about a driven roller, which feed roller comprises: a cylindrical doughnut-type feed roller com- Flledr 7, 1972 posed of a solid flexible elastomeric material, the
[21] Appl. No.: 313,136
[52] U.S. Cl. 29/129 [51] Int. Cl B211) 31/08 [58] Field of Search 29/129, 110, 124, 29/129.5, 132; 226/190, 191
[56] References Cited UNITED STATES PATENTS 1,712,087 5/1929 Medholdt 29/ 129 X 2,197,917 4/1940 Barton 29/129 X 3,225,692 12/1965 Oakes 29/ 129 X 3,537,632 11/1970 Watson.... 29/129'X 3,541,656 11/1970 Devon 29/124 X 3,602,970 9/1971 Smith 29/ 129 X Primary Examiner-Alfred R. Guest Att0rneyRichard P. Crowley inner diameter of the feed roller the approximate diameter of the driven roller about which the feed roller is to be secured, the roller characterized by a single opening extending from the outer to the inner surface of the feed roller to expose a first and second face surface, the surfaces adapted to be secured together, the feed roller composed of a material of sufficient flexibility to permit the feed roller to be opened to a distended position without permanent distortion and placed about the driven roller, the outer surface of the feed roller of sufficient coefficient of friction to move a material placed in contact therewith in operation; means to secure the first and second face surfaces in close sealing engagement and the feed roller about the driven roller; and means to relieve stress in the area opposite the first and second surfaces of the feed roller when the surfaces are in distended position.
14 Claims, 4 Drawing Figures ELASTOMERIC FEED ROLLER BACKGROUND OF THE INVENTION Devices for moving materials, particularly sheet materials, such as paper and cloth, employed by paper converters, textile manufacturers and the like, include a driven feed roller. Typically, one or more feed rollers are secured between the end plates, with the feed rollers composed of a steel roller having a bonded elastomeric, such as a rubber-coated, outer surface. The elastomeric coated surface has a high coefficient of friction so that when placed in contact with a movable material and the feed roller driven, the material is moved by being placed in contact with the rotating surface of the feed roller. In use, the elastomeric coating on the steel roller tends to wear or get out of round, and must be replaced. Often due to the construction of such feeding devices, it is difficult to remove the rubber-coated steel feeding rolls, while further, resurfacing such rolls with a new rubber or elastomeric coating is often quite tedious, time-consuming and expensive. For example, the defective roll must be removed from the device, the old elastomeric coating must then be removed, and then a new coating carefully bonded to the surface of the steel feed roller. In some cases, the steel feed roller comprises two semicircular halves, each half being carefully covered with a rubber coating to a required thickness, and then the steel roller secured together. Thus, the replacement, recovery and reinstallation of the elastomeric feed rollers have many disadvantages associated therewith.
SUMMARY OF THE INVENTION My invention concerns an elastomeric replacement feed roller, the devices employing my rollers and the method of installing and manufacturing my rollers. More particularly, my invention relates to a flexible solid elastomeric polyurethane feed roller which is adapted to be placed about a driven feed roller as the I many advantages the necessity of removing the underlying feed or driven roller. Unlike rubber-covered steel rollers, my feed roller is safer in that if dropped by a worker during installation, it does not cause damage either to the installer or to the roller which often occurs with the heavy rub-.
enough to return to a nonextended position when it assumes its usually doughnut-type structure.
My feed roller will be described in connection with the preparation, installation and use of a replacement feed roller comprised of a flexible solid elastomeric polyurethane resin. However, it is recognized that various modifications in materials and techniques may be employed which would fall within the scope of my invention. My replacement feed rollers may be employed in any device having a driven shaft which is designed to place the surface of the replacement feed roller in contact with the material to be removed, such as cloth, paper, canvas, steel, leather, plywood or other sheet materials, as well as a conveyer belt and the like. The material is moved by a frictional contact between the outer surface of the feed roller and the surface of the material to be moved. Depending on the particular material and the operation involved, the hardness, coefficient of friction, compression set, specific gravity, tensile strength, abrasion resistance, toughness and other properties of the particular polymeric material employed in manufacturing my feed rollers may be varied as desired.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a general schematic and representative cross-sectional view of a feed device showing my feed roller secured to the driven steel roller.
FIG. 2 is a general schematic and representative view of the installation of my feed roller about a driven roller.
FIG. 3 is a top plan view of my feed roller.
FIG. 4 is a side plan view of my feed roller.
DESCRIPTION OF THE INVENTION FIG. 1 shows a typical feed roller device 10 in general which comprises in combination: a steel driven roller 12 adapted to be rotated about its axis 14 by a motor 16. Typically, the driven roller 12 is secured for rotational movement between end plates (not shown) and I my solid feel roller 18 composed of an elastomeric posed of an elastomeric and flexible polymeric material provide long life in comparison to the rubber-coated steel roller. Although I am unable to explain fully the extraordinary long life of my replacement roller, and not wishing to be bound by any theory, it is believed that the roller life is extended by being separately secured about the driven roller. My replacement feed rollers are rapidly and simply installed and are designed as a single integral unit which is placed in a distended position by the installer about the driven roller on which the urethane surface is desired, and which is flexible may be spread apart to a distended position as to be sufficient to install the feed roller about the circumference of the driven roller while in place in the feed device.
FIGS. 3 and 4, together with FIGS. 1 and 2, illustrate my replacement feed roller 18 which is composed of a solid elastomeric polyurethane resin 20. One particular elastomeric urethane resin which may be employed will be described more particularly. However, any polymeric material, such as a natural or synthetic elastomeric polymer, may be employed which has the desired properties required. The material selected should have sufficient flexibility so that the feed roller 18 may be opened for installation without distortion and with a sufficiently low coefficient of friction to remove the feed roller. Typically, the tensile strength of the material should be greater than about 5,000 psi., preferably 6,000 to 7,000 psi. as measured by a Scott tensile strength tester device. Further, the hardness should preferably range from not more than 90 to 95A, and not lower than 30A when measured by a hardness Durometer device, while the compression set should be a maximum of 28 percent and a minimum of about 7 percent, the preferred average being about 22 to 28 percent, when measured in accordance with ASDM standards for 22 hours at 158F.
A typical solid elastomeric transparent casting-type polyurethane formulation for preparing a replacement feed roller would include a formulation which is a prepolymer, reacting with a hindered aromatic diamine or other curing agents. For example, one formulation suitable for use is as follows:
1as of asiip sn am qt yzns s s m eric pre-polymer based on poly(oxytetramethylerE glycols (Adiprene is a registered trademark of El. Demours DuPont and Company); and a 2. 13 grams of a hindered aromatic diamine composed of 4,4" methylene bis (2 chloroanalin) sold as MOCA, a registered trademark of El. Demours Du- Pont and Company.
My doughnut-type replacement feed roller 18 is composed of a cast polyurethane resin, and has a single cut surface 26, the cut extending generally radially through the solid material 20. An internally threaded nut 28 is secured integrally therein in one side of the surface 30 as defined by the cut in apassageway 20, and on the other side, the circular passageway 30 adapted for the insertion of a securing stove bolt 34 which is threadable into nut 28. The threading of the bolt 34 into nut 28 in the opposing passageway 30 forces the cut surface 26 of the feed roller 18 securely together and about the outer surface of the driven roller 12, so that the feed roller 18 and driven roller 12 rotate together. Positioned opposite the one side and integrally embedded,
in the feed roller 18 on the other side about the'passageway 30 is a retaining washer 32 so positioned so that the head of the bolt 34 when being tightened will not be pulled downwardly into the elastomeric polymeric composition 20. A portion of the resin 20 about the passageway 30 behind the nut is threaded as an additional safety and securing feature. The passageway in the polymeric material 20 is threaded slightly undersize as regards the threads of the bolt 34. On installation, the bolt 34, on being threaded through the nut 28, will contact the threaded elastomeric material 20 and aid in locking the bolt 34 securely. The passageway 30 on the bolt side extends to the outer surface 22 of the roller where it forms a generally elliptical opening 40 on the surface. Generally 180 from the cut surface 28, the feed roller 18 has a generally cylindrical or semicircular passage 36 extending through the roller, whose purpose is to relieve the stress on areas on the opposite side of the cut surface 26 when the roller is placed in its extended position during installation. The reduction in diameter in this area enables the feed roller to be spread apart when installed without unduly stretching or distorting the elastomeric polymeric material of the roller which might occur if the opposite area had no means for relieving such stress. I
In use, the feed roller 18 is typically cast into the desired dimension, and extended by the installer to an opening position slightly greater than the diameter of the steel driven roller 12 about which it is to be secured. The roller 18 is placed about the secured roller, while in the distended position, and then each side is allowed to assume its natural position and then forced together. The bolt 34 is inserted and threaded into place extending into the internal polymeric thread 38. The length and thickness of the roller 18 is dependent upon the particular use to which the roller is to be adapted. The internal diameter of the roller 18 is dimensioned to be approximately the same or slightly less than the diameter of the driven roller about which it is to be secured.
My replacement feed roller in one embodiment may be prepared by a molding or casting technique wherein a form for the passageway 30 is inserted through the outside of the mold directly into a mold cavity. The nut is then cleaned and a vulcanizing agent or other type of adhesive agent coated on the surface of the nut to insure that the nut bonds securely to the polymer, such as the urethane to be employed. The nut 34 and washer 32 are then placed within the mold in a suitable position and the components of the polyurethane elastomeric resin mixed, and then poured into the mold and permitted to cure into a gel state. When the resin reaches the gel state, the mold is compressed, such as by pressing together the two parts of the mold in a typical preload and a compression molding technique. The urethane resin is then heated to cure the resin and the replacement feed roller removed from the mold, and a radial cut made in the roller to expose surface 26.
A variety of suitable materials may be employed as the component resin used in preparing my replacement feed roller, although elastomeric urethane resins are particularly preferred because of their excellent compression set, long wear and abrasion-resistant characteristics. Other materials include natural and synthetic rubbers or other elastomeric material which may be molded, cast, extruded or fabricated into suitable shape. In addition, the means to relieve stress within my replacement feed roller has been shown as a semicircular passageway opposite the feed roller opening at the inner surface of the feed roller. However, the means to reduce the diameter and relieve stress may be employed, such as by employing shaped passageways located in the body of the feed roller in the area.
My replacement feed roller as described is simple and easy to make and of a unique design, readily and easily installed and overcomes many disadvantages of the prior art.
What I claim is:
1. A device for moving a material by frictional contact with the surface of a driven feed roller, which device comprises in combination:
a. a cylindrical drive roller adapted for rotary motion about its axis;
b. means to rotate the drive roller;
c. a doughnut-type feed roller secured about the periphery of the drive roller, the inner diameter of the feed roller approximately the diameter of the drive roller, the feed roller characterized by a single opening in its outer periphery from the inner to the outer surface to expose first and second surfaces, the feed roller composed of a solid elastomeric polymeric material, and having a sufficient flexibility to permit the feed roller to be opened to a distended position without permanent distortion and placed about the driven roller, and the polymeric material of a sufficient coefficient of friction to move the object when the outer surface of the roller is placed in contact with the object;
(1. means to secure the feed roller about the driven roller and to place the first and second surfaces of the feed roller in close sealing engagement, thereby presenting a continuous periphery of the polymeric material; and
e. means to relieve stress in the area opposite the first and second surfaces of the feed roller, and to prevent distortion of the feed roller when spread apart in a distended position prior to being secured about the driven roller.
2. The device of claim 1 wherein the means to relieve stress includes a passageway in the body of the feed roller, the passageway positioned generally directly opposite the opening in the feed roller.
3. The device of claim 1 wherein the means to secure the feed roller comprises:
a. a nut integrally embedded in the polymeric material adjacent the first surface;
b. a passageway in the polymeric material extending on either side of the first and second surfaces, on one side the passageway passing through the nut, and on the other side, extending to the outer sur- 7 face of the feed roller", and
c. a bolt within the polymeric material passed through the passageway on the other side and into threading engagement with the nut on the one side,
the bolt and nut securing the first and second surfaces together.
4. The device of claim 3 wherein the means to secure includes a retaining washer integrally secured within the polymeric material and about the passageway through which the bolt is passed, the bolt characterized by a head, the restraining washer preventing the bolt, on being tightened, from passing into the polymeric material- 5. The device of claim 4 wherein the p assag ewayim 8. A replacement feed roller adapted to be s'e'eured about the periphery of a driven roller for rotation therewith, which feed roller comprises in combination: a. a cylindrical doughnut-type feed roller composed of a solid flexible elastomeric material, the inner diameter of the feed roller the approximate diameter of the driven roller about which the feed roller is to be secured, the roller characterized by a single opening extending from the outer to the inner surface of the feed roller to expose a first and second face surface, the surfaces adapted to be secured together, the feed roller composed of a material of sufficient flexibility to permit the feed roller to be opened to a distended position without permanent distortion and placed about the driven roller, the outer surface of the feed roller of sufficient coefficient of friction to move a material placed in contact therewith in operation;
b. means to secure the first and second face surfaces in close sealing engagement and the feed roller about the driven roller; and
c. means to relieve stress in the area opposite the first and second surfaces of the feed roller when the surfaces are in distended position.
9. The feed roller of claim 8 wherein the means to relieve stress includes a passageway in the body of the feed roller, the passageway positioned generally directly opposite the opening in the feed roller.
10. The feed roller of claim 8 wherein the means to secure the feed roller comprises:
a. a nut integrally embedded in the polymeric material adjacent the first surface;
b. a passageway in the polymeric material extending on either side of the first and second surfaces, on one side the passageway passing through the nut, and on the other side, extending to the outer surface of the feed roller; and
c. a bolt within the polymeric material passed through the passageway on the other side and into threading engagement with the nut on the one side, the bolt and nut securing the first and second surfaces together.
11. The feed roller of claim 10 wherein the means to secure includes a retaining washer integrally secured internally threaded with the polymeric material to a diameter slightly less than the threads of the bolt.
- 13. The feed roller of claim 8 wherein the polymeric material consists essentially of a solid cast, elastomeric, flexible polyurethane resin.
14. The feed roller of claim 8 wherein the single opening is a radially extending cut in the feed roller from the outer to inner surface.