Abstract: A press mechanism that is powered by hydraulic, electrical and/or pneumatic means is provided with an improved ratchet and pawl machine which acts as a fail-safe device should any of the power means fail to lock the press parts in place. The fail-safe device includes a ratchet in the form of a circular or arcuate segment mounted with its circular center substantially coaxial with one of the turning parts of the mechanism or press, a pawl having a single tooth and a circular arcuate peripheral part that acts as a journal bearing and which in turn is supported by a pawl bearing which in turn is secured to a stationary part of the mechanism and has an arcuate journal which receives and supports the pawl therein. Tremendous load carrying capacity is thus achieved because of the large bearing area provided by the pawl bearing and the positioning of the respective ratchet and pawl teeth to employ a surface rather than point contact.

Abstract: A clamp for holding together the portions of a mold used in molding solid objects from a reacting liquid such as polyurethane has a C-shaped frame which is pivotally mounted on a pedestal to swing through an arc. The C-shaped frame of the clamp consists of an integral structure having an upper jaw connected by a column to a lower jaw. The frame supports a bed, crown and platen. The bed and crown are each a plate-like member that is mounted to pivot relative to one of the jaws. The platen is mounted preferably on the bed or lower one of such members. The mold portions are mounted on the crown and platen with the parts being arranged to move so that the mold portion engage and disengage. The invention also includes a method of molding wherein the mold portions are engaged and disengaged by a process that involves pivoting at least one and preferably both of the portions relative to the C-shaped frame.