Grommet device and method of forming

Abstract

A soft member constituting the main portion, and a rigid member. The soft member has a loop rib integral therewith, and the rigid member has a loop base element almost entirely embedded in the rib. The base element has load pads spaced there along for lockingly engaging the panel in which the grommet is positioned. The base member is molded in the bottom part of the mold, and then it is lifted out of its original molding position to expose it for injecting the soft material in surrounding position around the base member.

What is claimed is:  
     
         1 . A two step method of plastic injection molding an article having an outer shell and an inner core, comprising the steps, 
 providing a mold having a bottom part and a first and a second top part, said bottom part of the mold having a cavity formed therein to thereby define a shape of a bottom portion of an inner core of the article, said first top part of the mold having a cavity formed therein to thereby define a shape of a top portion of the inner core of the article, said second top part of the mold having a cavity formed therein to thereby define a shape of a top portion of the outer shell of the article;    providing ejection pins for moving at least a portion of the inner core of the article away from direct contact with the cavity of the bottom part of the mold;    fitting the bottom part of the mold together with the first top part of the mold;    forming the inner core of the article by injecting a first thermoplastic molding material into a space formed by the cavity of the bottom part of the mold and the cavity of the first top part of the mold;    separating the bottom part of the mold from the first top part of the mold;    moving at least a portion of the formed inner core away from direct contact with the cavity of the bottom part of the mold;    replacing the first top part of the mold with the second top part of the mold, and then    injecting a second thermoplastic molding material into a space formed by the cavity of the bottom part of the mold and the cavity of the second top part of the mold, thereby forming the article having at least a portion of the inner core of the article surrounded by the second molding material.    
     
     
         2 . The method according to  claim 1 , further including the step of molding radially spaced load pads extending from said inner core of the article.  
     
     
         3 . The method according to  claim 1 , wherein when at least a portion of the inner core of the article is moved away from direct contact with a portion of said cavity of the bottom part of the mold, at least a portion of each load pad remains in direct contact with the cavity surface of the bottom part of the mold.  
     
     
         4 . A method according to  claim 1 , wherein said first molding material has at least a Shore D hardness and the second molding material has at least a Shore A hardness.  
     
     
         5 . An article having an outer shell and an inner core wherein the article is plastic injection molded in two phases, said article comprising: 
 an inner member molded from a mold having a bottom part and a first and a second top part, said bottom part of the mold having a cavity formed therein to thereby define a shape of a bottom portion of the inner member, said first top part of the mold having a cavity formed therein to thereby define a shape of a top portion of the inner member, wherein said inner member is formed by injecting a first thermoplastic molding material into a space formed by the cavity of the bottom part of the mold and the cavity of the first top part of the mold when the bottom part of the mold is fitted together with the first top part of the mold; and    an outer member molded from the mold, said second top part of the mold having a cavity formed therein to thereby define a shape of a top portion of the outer shell of the article, said outer member is formed by injecting a second thermoplastic molding material into a space formed by the cavity of the bottom part of the mold and the cavity of the second top part of the mold, wherein at least a portion of the inner member of the article is surrounded by the second molding material;    
     
     
         6 . The article according to  claim 5 , further including radially spaced load pads extending from said inner member of the article.  
     
     
         7 . The article according to  claim 5 , wherein said first molding material has at least a Shore D hardness and the second molding material has at least a Shore A hardness.  
     
     
         8 . The article as recited in  claim 5 , wherein said article includes an aperture extending from an outer surface of said outer member to an inner surface of said outer member.  
     
     
         9 . The article as recited in  claim 5 , wherein a portion of said inner member forms a ring embedded within said outer member.  
     
     
         10 . The article as recited in  claim 5 , wherein said inner member extends out pads extending from the article, wherein a perimeter of each pad is surrounded by said outer member.  
     
     
         11 . The article as recited in  claim 10 , wherein an outer edge of said pads has a hook shape.