Apparatus for testing the tensile strength of sheet material
AssigneePulmac Instruments Ltd.
InventorsWavell Frederick Cowan, Bote Bruinsma
Life of this patent
Estimating the term…
Abstract
An improved testing device for testing the tensile strength of sheet material, such as paper, including a first pair of vertically moving jaws mounted on a support and a second pair of vertically moving jaws hanging from the first support in a pendulum manner and adapted to be at a dead-center position with the second pair of jaws juxtaposed to the first pair of jaws and in contact therewith for gripping a sheet of material to be tested therebetween. Low pressure, large diameter, pneumatic cylinders are provided for moving the lower jaws of each pair upwardly towards the fixed jaws against a self-aligning cylindrical spring.
Claims9
An apparatus for testing the tensile strength of fibers in a flat sheet comprising a base, a first support member on the base, a first pair of clamping jaws mounted to said first support member and adapted to receive and clamp a sheet material to be tested, said first support member extending above said first pair of jaws, a second support member pivoted to said first support member in pendulum manner, a second pair of clamping jaws mounted on said second support member opposite to said first pair of jaws and adapted to clamp said sheet material adjacent said first pair of jaws, said second support member pivoting in a pendulum manner and being at dead center with said second pair of clamping jaws being juxtaposed and in contact with the first jaws, means for pivotally causing the movement of the second support member away from dead center such that the pairs of jaws, while still clamping said sheet material, will move apart under pressure.
An apparatus for testing the tensile strength of fibers in a flat sheet comprising a base, a first support member on the base, a first pair of clamping jaws mounted to said first support member and adapted to receive and clamp a sheet material to be tested, a second support member pivoted to the first support member, a second pair of clamping jaws mounted on said second support member opposite to said first pair of jaws and adapted to clamp said sheet material adjacent said first pair of jaws, means for pivotally causing the movement of the second support member away from the first support member while the jaws are still clamping the sheet material, including an opening provided laterally through the first support member, an elongated wedge member adapted to move at a constant rate through said passage, push rod means connected to the second support member and extending within the passage and said first member and adapted to abut against the elongated wedge member such that as the wedge member is advanced through the passage at an ever increasing width, it will move the second member away from the first member by reason of the push means being moved by the wedge member.
An apparatus for testing the tensile strength of fibers in a flat sheet comprising a base, a first support member on the base, a first pair of clamping jaws mounted to said first support member and adapted to receive and clamp a sheet material to be tested, a second support member pivoted to said first support member, a second pair of clamping jaws mounted on said second support member opposite to said first pair of jaws and adapted to clamp said sheet material adjacent said first pair of jaws, means for pivotally causing the movement of the second support member away from the first support member such that the pairs of jaws, while still clamping said sheet material, will move apart under pressure, each said pairs of jaws including a first jaw fixed to the respective support member and a second jaw movable to and away from the first jaw and connected to the first jaw at least by a cylindrical resilient member normally urging the second jaw away from the first jaw.
Dependencies are inferred from the claim text.