Expanding mandrel assembly for a web-coiling core
AssigneeJagenberg Aktiengesellschaft
InventorKarl Thievessen
Life of this patent
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Abstract
An expanding mandrel for clamping a tubular member, especially a tubular core on which a paper web can be coiled in a machine for coiling the web or for supplying the web from a coil, has a pin with flat surfaces against which bracing elements support angularly equispaced segments in a cage which are pressed outwardly to urge convex surfaces of the segments against the inner surface of the core. Along longitudinal edges of the segments rounded rises or protuberances are provided which prevent stress peaks tending to damage the core.
Claims20
In an expanding mandrel apparatus for clamping a tubular member, especially a tubular core on which a paper web is adapted to be coiled, comprising a horizontal pin journaled for rotation about a horizontal axis, a plurality of angularly equispaced tubular segmental radially displaceable clamping elements surrounding said pin and mounted thereon, a cage surrounding said pin and maintianing said elements in position therearound, a cage surrounding said pin and maintaining said elements in position therearound, and respective bracing members between said pin and each of said elements for urging said elements radially outwardly into engagement with an inner surface of said tubular core, the improvement wherein:
- said elements have outer curvilinearly convex surfaces generally with a curvature corresponding to that of said inner surface, engageable with said inner surface and provided with widely spaced domed rises separated by a broad continuous convex surface.
In an expanding mandrel apparatus for clamping a tubular member, especially a tubular core on which a paper web is adapted to be coiled, comprising a horizontal pin journaled for rotation about a horizontal axis, a plurality of angularly equispaced tubular segmental radially displaceable clamping elements surrounding said pin and mounted thereon, a cage surrounding said pin and maintaining said elements in position therearound, and respective bracing members between said pin and each of said elements for urging said elements radially outwardly into engagement with an inner surface of said tubular core, the improvement wherein:
- said elements have outer curvilinearly convex surfaces engageable with said inner surface and provided with widely spaced domed rises, and
- said rises have centers of curvature for each element which lie along radii from said axis which are spaced from an axial medial plane through the respective element by an angle of substantially 20.degree. to 30.degree..
An expanding mandrel apparatus for clamping a tubular member, especially a tubular core on which a paper web is adapted to be coiled, comprising:
- a horizontal pin of generally prismatic cross section formed with pair of opposite flat surfaces and journaled for rotation about a horizontal axis;
- a plurality of angularly equispaced tubular segmental radially displaceable clamping elements surrounding said pin and mounted thereon;
- a cage surrounding said pin and maintaining said elements in position therearound;
- and
- respective bracing members between said surfaces of said pin and each of said elements for urging said elements radially outwardly into engagement with an inner surface of said tubular core, said elements having outer curvilinearly convex surfaces generally with a curvature corresponding to that of said inner surface, engageable with said inner surface and provided with widely spaced domed rises, separated by a broad continuous convex surface.
An expanding mandrel apparatus for clamping a tubular member, especially a tubular core on which a paper web is adapted to be coiled, comprising:
- a horizontal pin of generally prismatic cross section formed with pair of opposite flat surfaces and journaled for rotation about a horizontal axis;
- a plurality of angularly equispaced tubular segmental radially displaceable clamping elements surrounding said pin and mounted thereon;
- a cage surrounding said pin and maintaining said elements in position therearound;
- and
- respective bracing members between said surfaces of said pin and each of said elements for urging said elements radially outwardly into engagement with an inner surface of said tubular core, said elements having outer curvilinearly convex surfaces engageable with said inner surface and provided with widely spaced domed rises, said rises having crests which lie along an imaginary cylinder whose diameter is slightly greater than the inner diameter of said tubular core, said rises being formed as axially extending ribs adjacent opposite longitudinal sides of said elements, said rises having centers of curvature for each element which lie along radii from said axis which are spaced from an axial median plane through the respective element by an angle of substantially 20.degree. to 30.degree..
Dependencies are inferred from the claim text.