Chuck with improved torque transmission and centralization
AssigneeSonoco Development, Inc.
InventorsMarkku RONNILA, Ismo KERVINEN, Andrei KLIMENKO
Life of this patent
Estimating the term…
Abstract
An expansible chuck for holding hollow cylindrical cores used for winding and unwinding sheet material. A portion of the chuck body nearest the flange is stepped up so that the diameter of the chuck near the flange is slightly larger than the diameter of the rest of the chuck. The stepped up portion centers the chuck within the core which helps the expanding elements to uniformly grip the core.
Claims20
A chuck for receiving a hollow cylindrical core used for winding and unwinding a sheet of material, the core having an inner diameter (ID) and an outer diameter (OD), the chuck defining an axis (A) and comprising:
- a flange adapted to attach the chuck to a rotating support;
- a body extending axially from the flange, the body comprising one or more stepped portions near the flange and a distal portion farther away from the flange, the distal portion having a constant diameter (D2) that is less than the core inner diameter (ID), the distal portion and the core defining a gap therebetween when the core is mounted onto the chuck, the body defining a plurality of recesses;
- and
- a plurality of expansion elements circumferentially disposed around the body and adapted to grip an inner surface of the core, each expansion element nested within one of the recesses;
- wherein
- the one or more stepped portions have a diameter (D1) slightly larger than the diameter (D2) of the distal portion;
- and
- the one or more stepped portions are configured to contact the core inner surface and center the chuck inside the core when the core is mounted onto the chuck.
A method of holding a hollow core of the type used for winding and unwinding a wound material, the core having an inner diameter (ID), the method comprising the steps of:
- providing a pair of chucks, each chuck comprising a flange, a body extending axially from the flange and a plurality of expansion elements circumferentially disposed around the body, the body comprising one or more stepped portions near the flange and a distal portion farther away from the flange, the distal portion having a constant diameter (D2) that is less than the core inner diameter (ID), the distal portion and the core defining a gap therebetween when the core is mounted onto the chuck, the one or more stepped portions having a diameter (D1) slightly larger than the diameter (D2) of the distal portion;
- attaching each chuck to a rotating support;
- and
- inserting each chuck into an end of the core until the one or more stepped portions contact the core inner surface and center the chuck inside the core.
A method of centering a chuck within a hollow core, the core having an inner diameter (ID), the method comprising the steps of:
- providing a chuck comprising a flange, a body extending axially from the flange and a plurality of expansion elements circumferentially disposed around the chuck, the body comprising one or more stepped portions near the flange and a distal portion farther away from the flange, the distal portion having a constant diameter (D2) that is less than the core inner diameter (ID), the distal portion and the core defining a gap therebetween when the core is mounted onto the chuck, the one or more stepped portions having a diameter (D1) slightly larger than the diameter (D2) of the distal portion;
- attaching the chuck to a support;
- and
- inserting the chuck into an end of the core until the one or more stepped portions contact the core inner surface.
Dependencies are inferred from the claim text.