Injection molding systems incorporating so-called “hot runners” for distribution of molten thermoplastic material to one or more injection nozzles are generally known. In a typical hot runner system, the injection nozzles project away from a face of the hot runner system for insertion into a splittable mold formed by a first mold plate referred to as the core plate and a second mold plated referred to as the cavity plate such that the tip of the injection nozzle projects to a mold cavity formed between the mold plate and the cavity plate. Injection of thermoplastic material into this cavity causes a part to be formed conforming generally to the contours of the cavity. Upon separating the mold plate from the cavity plate, the cavity is exposed and the formed, solidified part may be withdrawn. Of course, numerous variations to this basic process may be utilized as desired.
Regardless of the final arrangement of the hot runner system and associated mold, it may be necessary to periodically service the injection nozzles and supporting equipment within the hot runner system. In previous systems, the hot runner generally has been integrally constructed with the molten material feed system and has not been readily susceptible to rapid replacement. Thus, any maintenance required on the hot runner system has necessitated the removal of the mold plates, followed by the on-site repair of the hot runner system. Such on-site repair removes the injection molding machine from use until the repair is fully completed. Specifically, repairing the hot runner system within the injection molding machine may result in the injection molding machine being out of operation for a period of several days while the repairs are taking place. This period of lost service may correlate to a substantial financial loss as parts cannot be manufactured during that time.
By way of example only, and not limitation, one prior system that may be used to provide access to a hot runner system is illustrated and described in U.S. Patent Application Publication US2006/0269649 A1, having a publication date of Nov. 30, 2006. As best understood, in the process disclosed in this reference, the mold plates are closed together and secured so as to form a unitary mold module. The mold plates are thereafter released from the hot runner manifold plate and the mold module is pulled away from the runner and lifted out of place, thereby exposing the hot runner for access during a repair. However, as best understood, there is no mechanism provided for removal of the complex hot runner system. Rather, the hot runner may be required to remain in place during the entire period of repair, thereby rendering the entire injection molding system inoperable during that period.