German toolmaker Otto Männer has invented a new energy- and time-saving approach to injection molding using a temperature-controlled baseplate.
Inventor Hans-Peter Männer says parts can be cooled in a movable mold half while others are being molded in a different—and potentially more economical– take on a rotary process. The invention is a new twist on a concept of moving mold halves on mechanical tracks used in previous Männer designs.
In an important aspect of the concept, part cooling can continue in a machine cooling station. The mold is opened prior to complete solidification of the part. The section of the tool with the part is transported and placed into thermal contact with a cooling station.
The first mold part remains on the machine nozzle and is not cooled. “Since only the second mold part of the mold is cooled, the injection molding machine enables energy-saving operation. The injection molding machine moreover saves space.”
Cooling is achieved in a water channel in an aluminum plate that is pressed against the surface of the mold with a pneumatic cylinder. Männer says that a cooling gas can be used in place of water.
“Simultaneously transporting the tool between the stations considerably reduces the cycle time of the injection molding machine. It is only limited by the longest dwell time the tool spends in a station.”
Linear conveyors configured at right angles are used to transport the mold sections. Rotary actuators are used to connect the ends of the conveyors. Mold halves can also be heated in a heating station.
The patent outlines other advantages of the invention including improved thermal stability of the machine parts.
Interestingly, the invention is most useful for large parts that require significant cooling times.
Recent inventions from Otto Männer have focused on micro molding, particularly in the packaging, medical and pharmaceutical markets.
Männer launched a complete micro-molding cell at K2010 in Düsseldorf. The micro-män 50 is a 5-metric-ton, all-electric machine using a standardized, two-piece mold half with a mold insert and integrated ejector package. The hot half travels horizontally around the machine on a track. At K2013, the company introduced an add-on micro injection unit called duo-män.
Otto Männer traces its roots to 1965 in Bahlingen, Germany when Otto und Christel Männer began manufacturing punching tools and special machines. In 1976, the company began producing simple injection molds. The company built its reputation designing and building precision molds for thin-wall products manufactured in large quantities with short cycle times.
Männer was purchased in late 2013 by the Barnes Group for $372 million. Since then, employment at the company has grown from 300 to 500 at sites in Germany, Switzerland and Lawrenceville, Georgia.