Abstract: Apparatus and method are disclosed for calibrating a load cell such as a load cell used in apparatus for measuring the forces applied to a pull tab during the formation of an opening in a container lid. The load cell first transmits a signal to a computer-recorder which is indicative of a no force applied condition. A known maximum force is then applied to the load cell which transmits a signal to the computer-recorder which is indicative of a known maximum force applied condition. An intermediate known force is then applied to the load cell which transmits a signal to the computer-recorder which is indicative of a known intermediate force applied condition. The computer-recorder uses the three signals to establish a load slope for use in the force measuring apparatus.

Abstract: Apparatus for measuring the forces applied to a pull tab during the formation of an opening in a container lid having an upper and lower surface with a pull tab hingedly secured on the upper surface and a score line in the container lid defining an opening and wherein one container lid at a time is fed into a holder having an opening therein so that a substantial portion of the upper surface of the container lid and all of the pull tab are exposed. A rotatable pull tab positioning head having a generally planar surface in which a recess in the shape of pull tab is formed is moved into resilient contact with the pull tab and is rotated relative to the container lid until the pull tab moves into the recess and thereafter the container lid and pull tab rotate with the positioning head to position the pull tab at a predetermined location. A load cell assembly having a pivotal hook member is moved into position with the hook member between the upper surface of the container lid and the pull tab.

Abstract: An apparatus for measuring the volume of a mold cavity of the type having a plurality of small dimension air venting passages in communication with the mold cavity. The apparatus includes an extensible membrane enclosure which is inserted into the mold cavity and filled with liquid from a liquid-holding vessel connected to the extensible membrane enclosure. Measurement of liquid in the liquid-holding vessel with a calibrated scale assembly is made prior to and subsequent to filling of the extensible membrane enclosure for determining the volume of the mold cavity.