APPARATUS SUITABLE FOR USE IN WINDING ROLLS OF MATERIAL

Abstract: Apparatus suitable for use in winding foils of material, for example paper, is described. The apparatus comprises an expansible tube (20) for supporting, in its expanded condi­ tion, material being wound into a roll, the expansible tube (20) being sealingly fitted over a shaft (11) having at least one groove (12) extending along the surface thereof to allow fluid under pressure to be passed into the tube (20) to cause the tube to expand, and means for preventing expansion of selected parts of the expansible tube. In a preferred embodi­ ment, the preventing means comprises an inexpansible sheath (21) formed with a plurality of perforations (23) fitted over the tube.

Description: Title: "Apparatus suitable for use in winding rolls of material" THIS INVENTION relates to apparatus suitable for use in winding rolls of material, in particular rolls of paper. In conventional machines for winding rolls of paper it has been necessary to provide an intermediate or spacer member, for example a cylindrical cardboard support, between the winding shaft and the roll of paper so that a wound paper roll may be removed from a winding shaft. Figure 1 of the accompanying drawings illustrates a previously proposed winding machine wherein a hollow cylindrical cardboard support member 102 is placed over a paper winding shaft 101 and held in position on the shaft 101 by a positioning means 103, for example an air bag. The positioning means 103 serves to ensure that the longitudinal axis of the support member 102 remains coaxial with that of the shaft 101 and also to allow for easy removal of a wound paper roll from the shaft. A pair of driving rollers 2 and 2' are provided for driving the support 102 and therefore the shaft 101. A weighting roller 4 is provided to apply a downward force to the support member 102, and hence to the shaft 101. The weighting roller 4 is of course vertically movable and the rotational axes of the rollers 2, 2' and 4 are maintained parallel to the longitudinal axis of the shaft. Continuous paper 3 is fed to the support member 102 via the upper surface of the driving roller 2 and is then wound at least once round the support member to allow the winding torque of the shaft 101 to be transmitted to the next section. The weighting roller 4 is then brought into engagement with the wound paper to provide for smooth and even winding of the paper. The circumferential speeds of the driving rollers 2 and 2' and weighting roller 4, which rotate in the directions shown by the arrows in Figure 1, are synchronized. The weighting roller 4 which is vertically movable rises as the thickness of paper wound on the support member 102 increases. The paper is wound onto the support member mainly by the rotation of the driving rollers 2 and 2' and the weighting roller 4' and not by the rotation of the shaft 101 which serves only to position the support member 102. Radial positioning of the support member 102 is effected by the positioning means 103 while longitudinal positioning of the support member is effected by a pair of thrust bearings (not shown) which are provided at the ends of the shaft 101. Because the weight of the paper wound onto the support member 102 is born mainly by the driving rollers 2 and 2', the shaft 101 is not affected by the weight of the paper. Moreover, because the shaft neither transmits a winding torque to nor bears a tensile force on the paper 3, the diameter of the shaft can be made very small. In order that the support member 102 around which the paper is wound may be removed easily, the support member must have a thickness sufficient to resist deformation under the winding force due to the tensile force produced by the paper and against deformation of the wound paper itself. In practice, it is impossible to make the outer diameter of the shaft less than about 13 mm. Where the paper roll is for use in a register or a desk type computer, a 50 to 70 mm diameter roll is ordinarily required and it is considered that the support member mentioned above which is usually made of cardboard leads to a roll of paper which is overly bulky for use in small sized apparatus such as a register or a desk type computer. It is an object of the present invention to provide apparatus suitable for use in winding rolls of material which overcomes or at least mitigates the disadvantages of previously proposed apparatus. According to the present invention, there is provided apparatus suitable for use in winding rolls of material comprising an expansible tube for supporting, in its expanded condition, material being wound into a roll, the expansible tube being sealingly fitted over a shaft having at least one groove extending along the surface thereof to allow fluid under pressure to be passed into the tube to cause the tube to expand; and means for preventing expansion of selected parts of the expansible tube. The main advantage of apparatus embodying the present invention is that it may be used to provide uniform paper rolls without the need for an intermediate or spacer member. Moreover, the apparatus is simple in construction and compatible with conventional winding machines. Also, the apparatus is similarly convenient both for removal of a wound roll and formation thereof. For a better understanding of the present invention and to show how the same may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a schematic illustration of previously proposed apparatus; Figure 2 is a diagrammatic part-sectional view of apparatus in accordance with the present invention; Figure 3 is a cross-sectional view of the apparatus of Figure 2 taken on line Ifl-IlI of Figure 2; and Figure 4 is an enlarged side view of part of the apparatus of Figure 1. Referring now to the drawings, Figures 2 and 4 illustrate apparatus in accordance with the invention. As shown in Figure 2, a shaft 11 comprising a drill rod of 8 mm in diameter has a pair of diametrically opposed keyways 12 formed on its exterior surface and extending longitudinally of the shaft. The keyways 12 are both connected to a distribution conduit 13 which extends radially through the rod 11 and thus connects the keyways 12 together. The distribution conduit 13 is also connected to a vent pipe 14 which extends along the axis of the shaft to one end thereof. The one end of the shaft has an external screw-thread for connection to one end of a sleeve 15. The other end of the shaft 11 is rounded to form a hemi-spherical end 16 which in use of the apparatus bears against a thrust bearing (not shown). The sleeve 15 incorporates a vent pipe 18 which is connected to the vent pipe 14 of the shaft 11. A check valve 17 is provided at the other end of the sleeve 15. The check valve 17 may be, for example, a ball check valve. The sleeve 15 is connected by a screw-thread connection to one end of a cover 19 so that the cover 19 may be easily removed. The other end 24 of the cover 19 is hemi-spherically shaped to bear in use on a thrust bearing (not shown). An expansible tube 20 made of rubber or a plastics material having expansible properties, which may be, for example, of 7 mm diameter and 1.5 mm thickness, fits tightly over the shaft 11 which as mentioned above has an outer diameter of 8 mm. The open ends of the tube 20 are bound to the shaft 11 by fastening means 30 and 31, for example piano wire wound round the ends of the tube, so that the tube is kept airtight. The rubber tube 20 extends along the shaft 11 over the area that will be covered by the paper to be wound onto the shaft. Thus, the tube is of 900 mm in length, equivalent to the greater part of the length of the shaft. Insertion of the shaft 11 into the tube 20 can be effected easily by supplying air or other suitable fluid under pressure to the keyways 12, via the check valve 17, vent pipes 18 and 14 and the distribution conduit 13 to cause the tube to expand. A hard inexpansible sheath 21 fits tightly over the expansible tube 20. The sheath 21 is applied to the tube 20 by initially covering the rubber tube 20 with a heat-contractible plastics tube for example a bridged or crosslinked polyolefin tube. The heat contractible tube is then heated causing the plastics tube to contract to form tightly round the tube 20. The sheat 21 is then cooled and hardens. It is desirable to use such heat-contractible plastics tube because the thickness of the contracted sheath will be about 0.6 mm. Holes 23 of 3 mm diameter are provided on the circumferential surface of the sheath 21 extending in rows longitudinally of the sheath 21 and separated by 10 mm so as to extend uniformly over the whole surface of the sheath as shown in Figure 4. It is desirable for the holes 23 to be produced in the contractible tube before it is fitted over the expansible tube 20. Prior to commencing a winding operation, the cover 19 is removed from the shaft. Air under pressure, for example at a pressure of 4-5 kg/cm2 (4 x 10-5to 5 x 10'5Nm- is supplied from the check valve 17 to the keyways 12 via the vent pipes 18 and 14 and distribution conduit 13. Air thus enters the space between the shaft 11 and the expansible rubber tube 20 against the tensile strength thereof. The rubber tube 20 will therefore expand uniformly through all the holes 23 in the sheath 21 to form hemi-spherical protrusions extending from the holes 23. The air supply is cut-off so that the circumferential hemi-spherical protrusions formed in the tube 20 extend by about 1 mm from the surface of the sheath. The cover 19 is then reconnected to the shaft and the shaft is then installed in a winding machine such as that shown in Figure 1. A continuous sheet of paper or other material is then fed to the shaft and is wound at least once directly round the shaft to secure it in place. A weighting roller 4 is then lowered onto the wound paper and driving rollers 2 and 2' are driven to rotate the shaft causing the paper or other material to be wound onto the shaft. Although during the winding operation the hemi-spherical protrusions of the tube 20 may be subjected to a winding force caused by the tensile strength of the paper or the material being wound, the winding force is, in practice, negligible so that the paper wound onto the shaft rests on the hemispherical protrusions of the tube 20 and does not touch the sheath itself. Consequently, when a certain predetermined length of paper is wound on the shaft, paper rolls of uniform size can be obtained. After a winding operation, the wound roll of paper or other material may easily be removed from the shaft. Thus, first the shaft itself together with the paper or other material retained thereon is removed from the winding apparatus and the cover 19 is removed so that the check valve may be opened to deflate the rubber tube 20 allowing the roll of paper or other material to be removed from the shaft. Although, in the apparatus described above, a shaft of 8 mm diameter is used, it may be practicable to use on 5 mm diameter shaft enabling more paper or other material to be wound into the same size roll as would be made by a larger shaft. It should therefore be understood that the size or length of the shaft is not limited to that described above. Moreover, instead of key ways which extend longitudinally of the shaft 11, a spiral groove or spiral grooves may be provided on the circumferential surface of the shaft. Also, instead of a hard sheath which covers a large area of the shaft, heat-contractible plastics tape of, for example, 5 mm width, may be wound in a spiral onto the expansible tube 20 to form a spiral space of, for example, 5 mm width, through which the tube 20 may expand. Alternatively, cylindrical sheaths formed from heat-contractible plastics tubing may be provided at intervals of, for example, 5 mm along the length of the tube 20, so that the exapnsible tube 20 may expand between them.

Claims: CLAIMS: 1. Apparatus suitable for use in winding rolls of material, comprising: an expansible tube for supporting, in its expanded condition, material being wound into a roll, the expansible tube being sealingly fitted over a shaft having at least one groove extending along the surface thereof to allow fluid under pressure to be passed into the tube to cause the tube to expand; and means for preventing expansion of selected parts of the expansible tube. 2. Apparatus according to claim 1, wherein the means for preventing expansion of selected parts of the expansible tube comprises an inexpansible sheath fitted over the expansible tube, the inexpansible sheath being formed with a plurality of perforations through which the expansible tube is allowed to expand. 3. Apparatus according to claim 2, wherein the perforations are of a size such that, when the expansible tube is expanded, the parts of the tube projecting through the perforations have a hemi-spherical shape. 4. Apparatus according to claim 1, wherein the means for preventing expansion of selected parts of the expansible tube comprises a plurality of inexpansible tubular members fitted over the expansible tube and spaced apart along the length of the expansible tube. 5. Apparatus according to any preceding claim, wherein the means for preventing expansion of selected parts of the expansible tube is formed of a heat contractible plastics material. 6. Apparatus according to any preceding claim, wherein the or each groove is connected to valve means for controlling the supply of fluid to the expansible tube. 7. Apparatus according to any preceding claim, wherein the shaft has a removable cover means at one end thereof. 8. Apparatus according to claim 7, wherein an outer end of the cover means is of hemi-spherical shape for seating in a thrust bearing. 9. Apparatus according to claim 7 or 8, wherein the other end of the shaft is of hemi-spherical shape for seating in a thrust bearing.

Inventors: NARITA, KEIZO KITSHOIN GARDEN HEIGHTS 234, ONO, SHINICHIRO
Applicants: NISHIMURA SEISAKUSHO CO. LTD.
Application year: 1982
Main classification: B65H75
IPC codes: B65H75, B41J15, B65H18