Apparatus for compressively treating flexible sheet materials

An apparatus for driving and longitudinally compressively treating a continuous web of material, the apparatus comprising:

• a cylindrical drive roll having a gripping surface for advancing the web in response to face-wise pressure of the web against the roll,
• a sheet assembly comprising a smooth-surfaced sheet-form primary member arranged over the drive roll to press the web face-wise into driven engagement with the drive roll, and a generally-stationary sheet-form retarder means downstream of said primary member to engage and retard the web,
• a sheet holder for positioning said sheet assembly in operative position over said drive roll with said sheet-form primary member extending from said sheet holder in the direction of travel of said web so that it presses said web face-wise against said drive roll,
• said sheet assembly having a configuration securely affixed to and standing from one face of the assembly, said standing configuration extending transverse to the direction of travel of said web,
• said sheet holder defining a channel transverse to the direction of travel of said web for engagement with said sheet assembly, said channel being open at one of its ends for endwise insertion of said sheet assembly, including said standing configuration that is securely affixed to said assembly, into said sheet holder by sliding motion in said transverse direction, said sheet holder having a reference surface engageable with said standing configuration of said assembly to precisely determine the position of said sheet assembly in the longitudinal direction relative to said drive roll and retain said sheet assembly against movement in the direction away from said sheet holder.

A replaceable, preassembled pressing and retarding sheet unit fur use in an apparatus for longitudinal compressive treatment of a continuous web of material, the apparatus comprising a cylindrical drive roll for advancing the web and a sheet holder configured to operatively press said sheet unit against the web thereby to compress the web between said preassembled sheet unit and the drive roll, said preassembled sheet unit comprising:

• a smooth-surfaced sheet-form primary member configured to be disposed over the drive roll to press the web into driven engagement with the drive roll;
• sheet-form retarder means joined to said primary member and extending downstream of said primary member for engagement with the web to retard motion imparted to the web by the interaction of said primary member and said drive roll;
• and
• a configuration securely affixed to and standing from a face of said preassmbled sheet unit and configured to mate with a complementary feature of the sheet holder, said standing configuration being arranged to position said preassembled sheet unit operatively over the drive roll with said preassembled sheet unit extending from the sheet holder in the direction of travel of the web and to retain said preassembled sheet unit against movement in the direction of travel of the web away from the sheet holder;
• said sheet-form primary member, said sheet-form retarding means, and said standing configuration being assembled and joined together to allow said preassembled sheet unit to be handled as a unit by an operator of the apparatus.