Methods of and apparatus for molding articles through a balanced, removable runner system

A method of molding a plurality of articles through a balanced distribution system, said method including the steps of:

• flowing an injection molding material into an infeed channel;
• distributing the injection molding material from the infeed channel through a primary runner channel system which is disposed along a single vertical plane to a plurality of locations which are spaced equidistantly from the infeed channel;
• guiding the injection molding material from the locations through a secondary runner channel system into each of a plurality of cavities having a contour of the articles to be molded and being spaced equidistantly from the locations;
• causing the injection molding material to solidify;
• causing the solidified injection molding material in the secondary runner channel system to be separated from that in the cavities;
• separating surfaces which define the cavities by causing relative movement between the surfaces in a direction parallel to the plane to facilitate removal of the articles from the cavities;
• and
• separating surfaces which define at least the primary runner channel system by causing relative movement therebetween in a direction transverse to the plane, and moving surfaces which define at least a portion of the secondary runner channel system in a direction parallel to the plane to facilitate removal of the solidified injection molding material from the runner channel systems.

An apparatus for molding a plurality of articles disposed at least in one longitudinal array with a balanced, removable runner system, said apparatus comprising:

• supply means including an infeed channel for feeding an injection molding material;
• means including adjacent surfaces which extend along a plane and which define a runner channel system for distributing an injection molding material from the infeed channel to a plurality of locations which are spaced equidistantly from the infeed channel;
• channel means for guiding the injection molding material from the locations into each of a plurality of cavities having the contour of the articles to be molded and being spaced equidistantly from the infeed channel;
• means for causing the injection molding material to be solidified;
• means for causing the solidified injection molding material in said channel means to be separated from that in the cavities;
• means for separating surfaces which define the cavities by causing relative movement therebetween in a direction parallel to the plane to facilitate removal of the articles from the cavities;
• and
• means for separating surfaces which define the runner channel system by causing relative movement therebetween in a direction transversely of the plane to facilitate removal of the solidified injection molding material in the runner channel system.

An apparatus for molding a plurality of articles disposed at least in one longitudinal array with a balanced, removable runner system, said apparatus comprising:

• supply means including an infeed channel for feeding an injection molding material;
• means including adjacent surfaces which extend along a plane and which define a primary runner channel system for distributing an injection molding material from the infeed channel to a plurality of locations which are spaced equidistantly from the infeed channel;
• plate means having adjacent surfaces therebetween for defining a plurality of cavities each having the contour of one of the articles to be molded and being spaced equidistantly from the infeed channel, said vertical plane being normal to said adjacent surfaces of said plate means;
• a secondary runner channel system for guiding the injection molding material from the locations into each of the plurality of cavities;
• means for causing the injection molding material in said runner channel systems and in the cavities to be solidified;
• means for causing the solidified injection molding material in the secondary runner channel system to be separated from that in the cavities;
• means for separating surfaces which define the cavities by causing relative movement between surfaces which define the cavities in a direction parallel to the plane to facilitate removal of the articles from the cavities;
• and
• means for separating surfaces which define at least the primary runner channel system by moving them in directions transverse to the plane, and means for moving surfaces which define at least a portion of the secondary system in a direction parallel to the plane to expose the solidified injection molding material in the runner systems and facilitate its removal.

An injection molding apparatus for molding a plurality of articles with a balanced, removable runner system, said apparatus comprising:

• supply means for feeding an injection molding material;
• a stationary platen which includes a chamber defined partially by camming surfaces and an infeed channel for receiving injection molding material from the supply means;
• a moveable unit which includes:
• a supporting platen which is adapted to be moved subsequent to the inflow of injection molding material;
• and
• a first plate adapted to be moved with said supporting platen;
• a second plate which is disposed between said first plate and said stationary platen and which is adapted to be moved relative to said first plate and to said stationary platen, said first and second plates cooperating to provide a plurality of cavities therebetween for receiving injection molding material from which the articles are molded;
• block means disposed within said chamber adjacent to said second plate and separable along a vertical parting plane in directions transverse of said parting plane for defining a distribution system to guide injection molding material from the infeed channel to the cavities, said distribution system including runner channels and having at least a substantial portion disposed along said parting plane and being arranged to cause the cavities to be spaced equidistantly from the infeed channel, said parting plane being normal to surfaces of said first and second plates and of said stationary platen which engage each other during feeding of the injection molding material and which are adapted to become spaced apart subsequent thereto;
• means for causing the injection molding material in the distribution system and in the cavities to be solidified;
• means disposed within said second plate and adjacent to said stationary platen and responsive to movement of said movable unit for causing said second plate to become spaced from said stationary platen and said block means to separate the solidified injection molding material in the distribution system from that in the cavities;
• and
• means for causing portions of said block means to become spaced apart and from said second plate and for causing said second plate to become spaced from said first plate to allow the solidified injection molding material in the distribution system and in the cavities to be removed from said apparatus.