Apparatus and Method for Producing Resin Product

Abstract

An apparatus produces a resin product which includes a first resin layer partially covered with a second resin layer so that a boundary line between the first and second resin layers is visible from the outside. The apparatus may include a first mold side having a recess, a second mold side configured and dimensioned to enclose the recess of the first mold side, a slide core movably fitted in the recess of the first mold side, which may be movable toward the second mold side to an extracted position to define a first cavity, and may be movable rearward to a retracted position after a first resin is injected into the first cavity to form the first resin layer, thus defining a second cavity into which a second resin is injected to form the second resin layer, the slide core including a dam dimensioned and configured to form a groove in the first resin layer during the formation of the first resin layer, wherein the dame partially positioned in the groove during the formation of the second resin layer, a first resin supply unit for supplying the first cavity with the first resin, and/or a second resin supply unit for supplying the second cavity with the second resin. The resin product produced by the apparatus is excellent in appearance, and obviates the post-processing formation of a tear line. Methods of forming the resin product are also described.

1 . An apparatus for producing a resin product which includes a first resin layer partially covered with a second resin layer so that a boundary line between the first and second resin layers is visible from the outside, comprising:
 a first mold side having a recess;   a second mold side configured and dimensioned to enclose the recess of the first mold side;   a slide core movably fitted in the recess of the first mold side, which is movable toward the second mold side to an extracted position to define a first cavity, and is movable rearward to a retracted position after a first resin is injected into the first cavity to form the first resin layer, thus defining a second cavity into which a second resin is injected to form the second resin layer, the slide core including a dam dimensioned and configured to form a groove in the first resin layer during the formation of the first resin layer, wherein the dame partially positioned in the groove during the formation of the second resin layer;   a first resin supply unit for supplying the first cavity with the first resin; and   a second resin supply unit for supplying the second cavity with the second resin.   
     
     
         2 . The apparatus according to  claim 1 , wherein the recess is a stepped structure including a first recess section and a second recess section having a greater depth than that of the first recess section, and the slide core is positioned in the second recess section. 
     
     
         3 . The apparatus according to  claim 1 , wherein the dam is formed along a circumference of the slide core. 
     
     
         4 . The apparatus according to  claim 1 , wherein the second mold side includes a wedge ridge for forming a tear line in the first resin layer. 
     
     
         5 . The apparatus according to  claim 4 , wherein the slide core includes a pressure sensor for measuring a pressure of resin in a vicinity of the wedge ridge. 
     
     
         6 . A method of producing a resin product which includes a first resin layer partially covered with a second resin layer so that a boundary line between the first and second resin layers is visible from the outside, comprising:
 closing a first mold side having a recess with a second mold side;   moving a slide core fitted in the recess of the first mold side toward the second mold side to an extracted position to define a first cavity, the slide core including a dam to form a groove in the first resin layer;   filling the first cavity with a first resin to form the first resin layer;   moving the slide core to a retracted position, thus defining a second cavity while the dam is partially disposed in the groove of the first resin layer; and   filling the second cavity with a second resin to form the second resin layer.   
     
     
         7 . The method according to  claim 6 , wherein the recess is a stepped structure including a first recess section and a second recess section having a greater depth than the first recess section, and the slide core is positioned in the second recess section, the method further comprising filling the first cavity with the first resin such that when the first cavity is fully filled with the first resin, a region of the first resin layer corresponding to the second recess section has a thickness less than that of a remaining region of the first resin layer. 
     
     
         8 . The method according to  claim 6 , wherein the second mold side includes a wedge ridge forming a tear line in the first resin layer. 
     
     
         9 . The method according to  claim 8 , further comprising measuring a pressure of the second resin in a vicinity of the wedge ridge while filling the second cavity with the second resin, and controlling an injection pressure of the second resin so as to maintain the pressure of the second resin within a predetermined range. 
     
     
         10 . A method of producing a resin product which includes a first resin layer partially covered with a second resin layer so that a boundary line between the first and second resin layers is visible from the outside, comprising:
 closing a first mold side having a recess with a second mold side, the second mold side including a wedge ridge for forming a tear line in the first resin layer;   moving a slide core fitted in the recess of the first mold side toward the second mold side to an extracted position to define a first cavity;   filling the first cavity with a first resin to form the first resin layer;   moving the slide core to a retracted position to define a second cavity; and   filling the second cavity with a second resin to form the second resin layer and measuring a pressure of the second resin in a vicinity of the wedge ridge, and controlling pressure of injection of the second resin so as to maintain the pressure of the second resin within a predetermined range.   
     
     
         11 . The apparatus according to  claim 1 , wherein the groove in the first resin layer has a thickness ranging from about 1 mm to about 2 mm. 
     
     
         12 . The apparatus according to  claim 11 , wherein the groove in the first resin layer have a thickness ranging from about 1 mm to about 1.5 mm. 
     
     
         13 . The apparatus according to  claim 1 , wherein the dam extends toward the second mold side along an outer circumference of the slide core with a predetermined height. 
     
     
         14 . The apparatus according to  claim 1 , wherein the second mold side includes a wedge ridge, extending along on an upper surface thereof within the dam and toward the slide core, for forming a tear line in the first resin layer. 
     
     
         15 . The apparatus according to  claim 14 , wherein the height of the wedge ridge is smaller than thickness of the first resin layer. 
     
     
         16 . A vehicle crash pad formed by the method according to  claim 6 . 
     
     
         17 . A vehicle crash pad formed by the method according to  claim 10 .