Insert to reduce weld line appearance defect in injection molding

Abstract

A molded part and methods of forming the part are provided by the present disclosure. The molded part defines adjacent outer surfaces and includes at least one weld line extending between the adjacent outer surfaces. The molded part includes an insert disposed at the weld line and extending at an angle between the adjacent outer surfaces. The insert functions to reduce the visibility and/or mechanical impact of weld lines in molded parts.

What is claimed is: 
     
         1 . A molded part defining adjacent outer surfaces and comprising at least one weld line extending between the adjacent outer surfaces, the molded part comprising:
 an insert disposed at the weld line and extending at an angle between the adjacent outer surfaces.   
     
     
         2 . The molded part according to  claim 1 , wherein the insert defines a reverse-S cross-sectional geometry. 
     
     
         3 . The molded part according to  claim 1 , wherein the insert is a polymeric material. 
     
     
         4 . The molded part according to  claim 1 , wherein the molded part is a single polymeric material. 
     
     
         5 . The molded part according to  claim 1 , wherein the molded part comprises at least two polymers, and the insert is a material of one of the at least two polymers. 
     
     
         6 . The molded part according to  claim 1 , wherein the molded part comprises at least two polymers, and the insert is a material that is different than the at least two polymers. 
     
     
         7 . The molded part according to  claim 1  further comprising a plurality of weld lines and a corresponding plurality of inserts disposed at the plurality of weld lines, each insert extending at an angle between the adjacent outer surfaces of the molded part. 
     
     
         8 . The molded part according to  claim 1 , wherein the molded part defines a thickness at the weld line, and the insert extends through at least 90% of the thickness. 
     
     
         9 . The molded part according to  claim 1 , wherein the molded part is fiber-reinforced. 
     
     
         10 . A method of forming a part comprising:
 locating an insert at an angle within a mold cavity;   sending a quantity of molten resin through the mold cavity to form a first melt front; and   sending another quantity of molten resin through the mold cavity to form a second melt front,   wherein the first melt front meets the second melt front at a weld line and each front flows along opposite sides of the insert.   
     
     
         11 . The method according to  claim 10 , wherein the method comprises injection molding. 
     
     
         12 . The method according to  claim 10 , wherein the mold cavity defines opposed internal surfaces, and the insert is disposed at an angle between the internal surfaces at the weld line. 
     
     
         13 . The method according to  claim 12 , wherein one end of the insert is fixedly located to one of the opposed internal surfaces, and another end of the insert floats within the mold cavity. 
     
     
         14 . The method according to  claim 10  further comprising:
 locating a plurality of inserts at an angle within at least one mold cavity; and 
 sending a plurality of quantities of molten resin through the mold cavity to form a plurality of melt fronts, 
 wherein the plurality of melt fronts meets adjacent melt fronts at a plurality of weld lines and each adjacent front flows along opposite sides of each insert. 
 
     
     
         15 . The method according to  claim 10 , wherein both quantities of molten resin are a same polymeric material. 
     
     
         16 . The method according to  claim 10 , wherein each of the quantities of molten resin are a different polymeric material. 
     
     
         17 . The method according to  claim 10 , wherein the insert defines a material having a glass transition temperature greater than or equal to a glass transition temperature of each of the quantities of molten resin. 
     
     
         18 . A method of injection molding a part comprising:
 locating an insert at an angle within a mold cavity;   injecting a quantity of molten resin through the mold cavity to form a first melt front; and   injecting another quantity of molten resin through the mold cavity to form a second melt front,   wherein the first melt front meets the second melt front at the insert and each front flows along opposite sides of the insert.   
     
     
         19 . The method according to  claim 18 , wherein one end of the insert is fixedly located to one internal surface of the mold cavity, and another end of the insert floats within the mold cavity. 
     
     
         20 . The method according to  claim 18  further comprising:
 locating a plurality of inserts at an angle within the one mold cavity; and 
 sending a plurality of quantities of molten resin through the mold cavity to form a plurality of melt fronts, 
 wherein the plurality of melt fronts meets adjacent melt fronts at a plurality of weld lines, and each adjacent front flows along opposite sides of each insert.