Search

EP-4521964-B1 - QUICK ADJUSTABLE ROLLER FOR A CRIMPER FOR SHEET MATERIAL

EP4521964B1EP 4521964 B1EP4521964 B1EP 4521964B1EP-4521964-B1

Inventors

  • MELONCELLI, Niki
  • MINELLI, Gastone
  • ULIVI, Pierfrancesco
  • LEONE, LUIGI

Dates

Publication Date
20260513
Application Date
20230426

Claims (15)

  1. An adjustable roller (20) for a crimper for sheet material, comprising: a substantially cylindrical exterior portion (21) having a first end (22) and a second end (23) with a longitudinal axis of rotation (30) extending between the first end (22) and the second end (23); a first bushing (26) mounted inside the first end (22) of the roller and wherein the first bushing (26) has a cylindrical bore (28) with an axis that is parallel to the longitudinal axis of rotation (30); characterized in that a second bushing (126) is mounted inside the second end (23) of the roller (20); the second bushing (126) has a cylindrical bore (128) with an axis that is parallel to the longitudinal axis of rotation (30); wherein at least one of the first bushing (26) and the second bushing (126) is adjustably mounted inside the respective end (22, 23) of the roller (20) such the axis of the at least one of the first bushing (26) and the second bushing (126) is displaceable relative to the longitudinal axis of rotation (30).
  2. The adjustable roller according to claim 1, wherein the axis of the at least one of the first bushing and the second bushing is displaceable from the longitudinal axis of rotation by up to 1mm, optionally up to 0.5mm, optionally up to 0.1mm, optionally up to 0.05mm.
  3. The adjustable roller according to claim 1 or 2, wherein the at least one of the first bushing and the second bushing is mounted inside the respective end of the roller with a predetermined amount of play in a plane perpendicular to the longitudinal axis, and wherein the at least one of the first bushing and the second bushing is adjustably fixable relative to the respective end of the roller by a plurality of adjustable fixings.
  4. The adjustable roller according to claim 3, wherein the plurality of adjustable fixings comprises a plurality of set screws, wherein the substantially cylindrical exterior portion is provided with a plurality of radially-oriented, circumferentially-spaced threaded bores at the first end or the second end or both the first end and the second end, and wherein the plurality of set screws are adjustably rotatable within the threaded bores so as to hold the respective first bushing or second bushing securely in place relative to the respective first end or second end at selectable different displacements of the bushing axis relative to the longitudinal axis of rotation.
  5. The adjustable roller according to claim 1, wherein the axis of the at least one of the first bushing and the second bushing is offset from or skew to or both offset from and skew to the longitudinal axis of rotation; and wherein the at least one of the first bushing and the second bushing is rotatably adjustable relative to the cylindrical exterior portion so as to allow the axis of the at least one of the first bushing and the second bushing to be moved along an orbital path about the longitudinal axis during adjustment.
  6. The adjustable roller according to claim 5, wherein the offset or skewness or offset and skewness of the axis of the at least one of the first bushing and the second bushing from the longitudinal axis of rotation is provided by an eccentricity in the respective flange portion.
  7. The adjustable roller according to claim 5, wherein the offset or skewness or offset and skewness of the axis of the at least one of the first bushing and the second bushing from the longitudinal axis of rotation is provided by an eccentricity in the bushing.
  8. The adjustable roller according to any one of claims 5 to 7, wherein the offset of the axis of the at least one of the first bushing and the second bushing from the longitudinal axis of rotation is no greater than 1mm, optionally no greater than 0.5mm, optionally no greater than 0.1mm, optionally no greater than 0.05mm.
  9. A roller unit for a crimper for sheet material comprising a first adjustable roller according to any preceding claim, in combination with a second roller comprising a substantially cylindrical exterior portion having a first end and a second end with a longitudinal axis of rotation extending between the first and second ends, the longitudinal axis of the second roller being substantially parallel with the longitudinal axis of the first roller, and the first and second rollers being moveable relative to each other so as to bring the cylindrical exterior surfaces into close proximity along a tangential plane between the cylindrical exterior surfaces.
  10. The roller unit according to claim 9, wherein a fine adjustment of an orientation of the longitudinal axis of rotation of the substantially cylindrical exterior portion of the first roller relative to an orientation of the longitudinal axis of rotation of the substantially cylindrical exterior portion of the second roller is obtained by displacing the axis of the at least one of the first bushing and the second bushing relative to the longitudinal axis of rotation of the substantially cylindrical exterior portion of the first roller.
  11. A method of adjusting an orientation of a longitudinal axis of a roller (20) for a crimper for sheet material, wherein the roller (20) comprises: a substantially cylindrical exterior portion having a first end (22) and a second end (23) with a longitudinal axis of rotation (30) extending between the first end (22) and the second end (23); a first bushing (26) mounted inside the first end (22) of the roller (20) and wherein the first bushing (26) has a cylindrical bore (28) with an axis that is parallel to the longitudinal axis of rotation (30); characterized in that a second bushing (126) is mounted inside the second end (23) of the roller (20); wherein second bushing (126) has a cylindrical bore (128) with an axis that is parallel to the longitudinal axis of rotation (30); and wherein at least one of the first bushing (28) and the second bushing (128) is adjustably mounted inside the respective end (22, 23) of the roller (20) such the axis of the at least one of the first bushing (28) and the second bushing (128) is displaceable relative to the longitudinal axis of rotation (30); the method comprising adjusting a displacement of the at least one of the first bushing (28) and the second bushing (128) relative to the cylindrical exterior portion so as to displace the axis of the at least one of the first bushing (28) and the second bushing (128) relative to the longitudinal axis (30).
  12. The method according to claim 11, wherein the axis of the at least one of the first bushing and the second bushing is displaced from the longitudinal axis of rotation by up to 1mm, optionally up to 0.5mm, optionally up to 0.1mm, optionally up to 0.05mm.
  13. The method according to claim 11 or 12, wherein the at least one of the first bushing and the second bushing is mounted inside the respective end of the roller with a predetermined amount of play in a plane perpendicular to the longitudinal axis, wherein the at least one of the first bushing and the second bushing is adjustably fixable relative to the respective end of the roller by a plurality of adjustable fixings; and wherein the at least one of the first bushing and the second bushing is adjustably displaced relative to the cylindrical exterior portion by adjusting the adjustable fixings.
  14. The method according to any one of claims 11 to 13, wherein prior to adjusting the displacement of the at least one of the first bushing and the second bushing, the roller is adjustably mounted in a crimping machine frame substantially parallel to a second roller, and wherein the roller is adjusted within the frame to a first predetermined tolerance so that the substantially cylindrical portion of the roller is aligned with a corresponding substantially cylindrical portion of the second roller along a tangential plane where external circumferential surfaces of the roller and the second roller are in closest proximity.
  15. The method according to claim 14, wherein the roller is adjusted to a second predetermined tolerance, finer than the first predetermined tolerance, by adjusting the displacement of the at least one of the first bushing and the second bushing relative to the cylindrical exterior portion so as to displace the axis of the at least one of the first bushing and the second bushing relative to the longitudinal axis.

Description

The present disclosure relates to an adjustable roller, in particular but not exclusively an adjustable roller for a crimper to crimp, for example, tobacco sheet, polymer sheet or paper sheet, and also to an adjustable bushing for a roller such as a crimping roller. Equipment in the tobacco industry, like all equipment, is subject to maintenance. Any downtime means a financial loss, so it is crucial to get the equipment up and running again as soon as possible. After any maintenance or troubleshooting where parts have been disassembled and reassembled, the equipment parts must be adjusted with respect to each other. Production lines for tobacco products, including heat-not-burn aerosol-generating products, often include units in which sheets of material are passed between at least two rollers. The sheets of material may be unwound from bobbins to feed the rollers. A particular example is a crimping unit, in which first and second substantially cylindrical crimping rollers each having a longitudinal axis of rotation and each provided with a plurality of substantially parallel circumferential ridges about the external surfaces of the cylindrical crimping rollers are arranged in close proximity to each other with the first roller substantially parallel to the second roller such that the ridges of first roller interleave with the ridges of the second roller along a tangential plane where the external surfaces of the first and second rollers are in closest proximity. A sheet of material, for example a sheet of polymer material or a sheet of homogenized tobacco material, is passed between the first and second rollers and crimped by the interleaving circumferential ridges. It will be appreciated that the cylindrical crimping rollers must be adjusted in the micrometre range so as to ensure that the spacing between the external surfaces of the rollers at the tangential plane is substantially uniform in a direction parallel to the longitudinal axes of the rollers, with the ridges interleaving correctly to define a desired crimping amplitude. If the spacing is too narrow, the ridges may cut through the sheet of material, and if the spacing is too wide, the sheet of material may not be crimped correctly. Moreover, if the spacing is not substantially uniform along the lengths of the first and second rollers, then the sheet of material may not be crimped uniformly across its width. Adjustment of the rollers is particularly time-consuming and requires skilled maintenance personnel, as otherwise tolerances may be unintentionally exceeded, which will degrade the overall quality of the product being manufactured. Tolerances are typically on a micrometre scale, which requires a high level of precision in adjusting the crimping rollers. Figure 1 shows a prior art crimping unit comprising first and second crimping rollers, for example as disclosed in US 10,888,118. A continuous sheet of material is fed into the crimping unit between the first and second crimping rollers. The two crimping rollers are mainly tubular in shape and are mounted with two flanges on the outer ends of the crimping roller. A shaft is mounted along the longitudinal axis of each crimping roller as well as the axes of the mounting flanges, and the crimping roller can be driven by rotating the shaft, for example by way of an electric motor. The shaft is mounted on a support frame. This design of several parts assembled, as with any system, results in an accumulation of tolerances that must be readjusted by the maintenance personnel. The adjustment of the crimping rollers to each other takes time and has to be executed with the highest precision. Moreover, adjustment of the crimping rollers is a highly-skilled task that can take considerable time. US2020/046 015 A1 discloses an adjustable roller for a crimper and a method of adjusting an orientation of a longitudinal axis of such a roller according to the preamble of independent claims 1 and 11. According to a first aspect of the present invention, there is provided an adjustable roller for a crimper for sheet material, comprising: a substantially cylindrical exterior portion having a first end and a second end with a longitudinal axis of rotation extending between the first end and the second end;a first bushing mounted inside the first end of the roller and a second bushing mounted inside the second end of the roller;wherein the first bushing and the second bushing each have a respective cylindrical bore with an axis that is parallel to the longitudinal axis of rotation;wherein at least one of the first bushing and the second bushing is adjustably mounted inside the respective end of the roller such the axis of the at least one of the first bushing and the second bushing is displaceable relative to the longitudinal axis of rotation. When the roller is mounted on a shaft that extends through the cylindrical bores of the first and second bushings, with the shaft being supported by an external frame, displacem