New Recirculating RIM Spray Mixheads Offer an Improved Method for Even Material Distribution into Molds

摘要

Closed or open pour polyurethane molding of broad parts currently requires multiple or complex paths to fill with enough mixed material to reach the extremities of the mold. Adding to the pour-path time is the time required to expand to the mold extremities. The advantage in spraying a wide pattern instead of a stream is evident in that more surface area is covered per inch of robot travel, however the method currently in use requires flushing with water or air. Gusmer-Admiral, Inc. is developing a line of recirculating spray heads. The first head incorporates a 6mm rod diameter. (Figure 1.) These heads are designed to mechanically self-clean, eliminating the need for flushing. Fluids are continually recirculating through the mixing rod slots identically to RIM pour heads to assure accurate conditioning and eliminate cold shots at start-up. Plans are to insure that all standard high-pressure metering systems can be used with these new spray heads. The spray tip is designed to be assembled or disassembled without exposing any chemical to atmosphere. A variation of tips will be available as testing progresses to develop spray patterns of varying width in either fan or round configuration. (Table 1.) All tips and retainers coming in contact with mixed material are treated with a non-adhesive coating to improve cleaning. The Gusmer-Admiral spray head completely expunges all mixed material out of the chamber through the tip slot. The rod is actuated using a double-acting hydraulic cylinder, proven successful over the years with GAI mix-heads. Means are provided for a proximity switch to sense head opening for program requirements, problem diagnosis, and alarms. The applications of this product line fit nicely in the scope of Gusmer-Admiral available wet systems. Applications in automotive, furniture, construction, and recreation industries will be opened due to the ability to minimize application time and simplify maintenance.