Stretch frame
OwnerKaino J. Hamuinventor
Life of this patent
Estimating the term…
Abstract
A stretch frame for sheet material such as printing screen utilizes tensioning rollers to be secured to the sheet edges and then rotated to stress the sheet material. The rollers may be rotatably received within laterally opening channels in the frame and restrained against reverse rotation to release the sheet tension by a ratchet device extending along a substantial length of each roller. This construction insures that the printing screen or other web shaped material is rigidly held in place.
Claims28
In a stretch frame from stressing sheet material edgewise, the combination comprising:
- a sheet tensioning roller,
- a frame structure including bearing means engaging the external surface of said roller along a substantial portion of its length and rotatably supporting the roller for turning of the roller on its longitudinal axis,
- sheet gripping means on said roller for gripping an edge of said sheet material whereby rotation of said roller in one direction with the opposite edge of the material fixed to the frame stresses the material edgewise between said edges, and
- readily accessible means for rotating said roller.
In a stretch frame for stressing sheet material edgewise, the combination comprising:
- a sheet tensioning roller,
- a frame structure including bearing means rotatably supporting said roller along a substantial portion of its length, said bearing means comprising journal bearing means journalling said roller, and said roller provides the bearing journal, and
- sheet gripping means on said roller for gripping an edge of said sheet material whereby rotation of said roller in one direction with the opposite edge of the material fixed to the frame stresses the material edgewise between said edges.
In a stretch frame for stressing sheet material edgewise, the combination comprising:
- a sheet tensioning roller,
- a frame structure including bearing means rotatably supporting said roller along a substantial portion of its length, said bearing means comprising a bearing channel on said frame structure rotatably receiving said roller in journal-bearing-like fashion, and
- sheet gripping means on said roller for gripping an edge of said sheet material whereby rotation of said roller in one direction with the opposite edge of the material fixed to the frame stresses the material edgewise between said edges.
In a stretch frame for stressing sheet material edgewise, the combination comprising:
- a sheet tensioning roller,
- a frame structure including a hollow frame member along one side of the frame structure,
- bearing means rotatably supporting said roller along a substantial portion of its length comprising a bearing channel within and extending lengthwise of said frame member and rotatably receiving said roller in journal-bearing-like fashion,
- said frame member and channel having openings through which said sheet material is insertable into gripping engagement with said roller sheet gripping means and
- sheet gripping means on said roller for gripping an edge of said sheet material whereby rotation of said roller in one direction with the opposite edge of the material fixed to the frame stresses the material edgewise between said edges.
In a stretch frame for stressing sheet material edgewise, the combination comprising:
- a sheet tensioning roller,
- a frame structure including bearing means rotatably supporting said roller along a substantial portion of its length,
- sheet gripping means on said roller for gripping an edge of said sheet material whereby rotation of said roller in one direction with the opposite edge of the material fixed to the frame stresses the material edgewise between said edges,
- anti-rotation ratchet means extending along and acting on at least a major portion of the length of said roller for restraining said roller against reverse rotation.
In a stretch frame for stressing sheet material edgewise, the combination comprising
- a sheet tensioning roller,
- a frame structure including bearing means rotatably supporting said roller on said frame,
- sheet gripping means on said roller for gripping an edge of said sheet material, whereby rotation of said roller in one direction with the opposite sheet edge fixed to said frame stresses said sheet material edgewise between said edges, and
- anti-rotation means which comprises ratchet means operating between said frame structure and said roller along at least a substantial portion of the roller length for restraining said roller against reverse rotation.
A stretch frame for stressing sheet material edgewise, comprising:
- a rectangular frame structure,
- sheet tensioning rollers along the four sides, respectively, of said frame structure,
- bearing means on said frame structure engaging the external surface of said rollers along a substantial portion of the length of each roller and rotatably supporting said rollers for turning of each roller on its longitudinal axis,
- sheet gripping means on said rollers for gripping edges of the sheet material, whereby rotation of said rollers in one direction stresses the sheet material edgewise, and
- readily accessible means for rotating said roller.
Dependencies are inferred from the claim text.