Abstract: A rotary injection molding press having a rotatable platform with a plurality of mold blocks is disclosed, wherein a controller box containing individual temperature control units is mounted on the rotatable platform so as to reliably maintain independent temperature control of each mold block. The controller box includes a rotary coupler for providing a rotating electrical connection from the stationary frame to the controller box, wherein the rotary coupler comprises pairs of wetted electrodes connected through separated pools of mercury. Using this configuration, a highly reliable rotating connection is provided which is substantially frictionless and has a consistently low resistance. Furthermore, by locating the individual temperature control units in a single controller box positioned on the rotatable platform itself, the problem of routing the sensitive control loop signals through a rotating electrical connection is avoided.

Abstract: An improved rotary injection molding press for plastic parts of the type having a movable platform which indexes one or more manually opened and closed mold blocks to and from different stations on the press. Should an open mold block index from a preparation station to the index station where an injector mechanism injects fluid plastic into closed mold blocks, an actuator detects the open mold block to activate switch means to stop the press. Should a closed mold block index from a cooling station when the injected plastic cools in the mold block to an eject station which ejects the completed part from open mold blocks, a pin disposed in the mold block activates a switch to stop the press. Additionally a protective shroud is provided surrounding the injector mechanism to protect the press operator. Removal of the shroud activates a switch to stop the press.