Patent Publication Number: US-2021170706-A1

Title: Manufacturing method of injection molded composite shoe sole and sole thereof

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a Divisional of co-pending application Ser. No. 16/190,970, filed on Nov. 14, 2018, for which priority is claimed under 35 U.S.C. § 120; the entire contents of all of which are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to composite shoe soles, and more particularly, to a manufacturing method of injection molded composite shoe sole and sole thereof, wherein the injection molding material is combined with different material during the injection process. 
     2. Description of the Related Art 
     In a conventional shoe manufacturing field, shoes are often provided with accessories or cleats made of different material from the shoe sole. However, different materials are difficult to be combined, causing a less optimal product quality. Therefore, the industry has developed relative improvements. Referring to TW patent 1601491, a manufacturing method of shoe having cleat made of different material is disclosed, comprising steps of: preforming shoe cleats, in-mold positioning, facial processing, in-mold gluing, mold combining, sole material injecting, hot-melting combining, and mold separating. In the facial processing step above, a preformed shoe cleat is placed in the mold, and the shoe cleat undergoes the facial process and is coated with glue. Then, melted sole material is injected into the mold, such that the sole material is cooled down to be solidified into the shoe sole. 
     However, during the facial processing operation upon the shoe cleat, the treating agent and glue easily foul the internal structure of the mold. As a result, the overall manufacturing time is prolonged, and even the yield rate is affected. Further, based on the fact that the mold is usually under a high temperature environment, the danger during the facial processing of the shoe cleat is increased. 
     SUMMARY OF THE INVENTION 
     For improving the issues above, a manufacturing method of injection molded composite shoe sole is disclosed, which is able to increase the shoe manufacturing efficiency and also resolve the possible pollution during the combination of shoe cleats and the shoe sole, so as to improve the combination quality thereof. 
     For achieving the aforementioned objectives, a manufacturing method of injection molded composite shoe sole is provided, comprising following steps: 
     (a) facial modifying, cleaning a combination face of an additional component formed of a material different from the sole material, and coating a facial process layer on the combination face, and drying to modify the combination face; 
     (b) gumming, placing a gum layer on the facial process layer on the modified combination face; 
     (c) in-mold positioning, placing the additional component into a mold; and 
     (d) injection molding, injecting the sole material into the mold, thereby gumming the sole material and the gum layer of the combination face to form a composite shoe sole, wherein the components are combined to the bottom or peripheral portions of the composite shoe sole. 
     A composite shoe sole in accordance with an embodiment of the present invention is also provided, comprising a sole body and an additional component. The sole body has a sole face. The additional component is formed of a material different from the material of the sole body. The additional component has a combination face, which is combined with the sole face of the sole body, with a facial process layer and a gum layer disposed between the sole face and the combination face. The facial process layer is pre-formed on the combination face, and the gum layer is disposed between the facial process layer and the sole face. 
     With such configuration, the composite shoe sole is formed by the additional component and the sole material that are made of different materials. Regarding the overall shoe manufacturing process, the additional component undergoes the facial processing operation in advance, and is subsequently placed into the mold, so as to reduce the possible pollution caused upon the mold and increase the yield rate of the composite shoe sole thereby manufactured. Also, the facial processing outside of the mold further reduces the overall manufacturing time and helps improving the safety during the manufacturing process. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a flow chart of the manufacturing method of the composite shoe sole in accordance with an embodiment of the present invention. 
         FIG. 2  is a flow chart of the facial modifying process of the present invention. 
         FIG. 3  is a flow chart of the gumming process of the present invention. 
         FIG. 4  is a schematic view illustrating operation status of the injection molding process of the present invention. 
         FIG. 5  is a perspective view of the composite shoe sole in accordance with an embodiment of the present invention. 
         FIG. 6  is a partially sectional view of the composite shoe sole in accordance with an embodiment of the present invention. 
         FIG. 7  is a perspective view of the composite shoe sole in accordance with another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The aforementioned and further advantages and features of the present invention will be understood by reference to the description of the preferred embodiment in conjunction with the accompanying drawings. 
     Referring to  FIG. 1  to  FIG. 7 , a manufacturing method of injection molded composite shoe sole  100  and the composite shoe sole  100  thereof are provided. The composite shoe sole  100  comprises a sole body  10  and an additional component  20  formed of a material different from the material of the sole body  10 . The sole body  10  is formed of a sole material selected from TPU (thermoplastic polyurethanes), PA (Nylon), or TPE (thermoplastic elastomer) through a cooling process, with a sole face  11  on the bottom or peripheral portions thereof. The additional component  20  has a combination face  21 , which is combined with the sole face  11  of the sole body  10 . The manufacturing method of the injection molded composite shoe sole  100  comprises following steps: facial modifying S 1 ; gumming S 2 ; in-mold positioning S 3 ; and injection molding S 4 . 
     In the facial modifying S 1 , the combination face  21  of the additional component  20  is cleansed by use of water or detergent, such that the impurity on the combination face  21  is removed. In an embodiment of the present invention, the additional component  20  refers to protrusion, shoe cleats, or sole pat formed of rubber material or other material different from the material of the shoe sole. Next, a facial process layer  22  selected from, for example but not limited to, an environmental friendly oil-based benzene free treating agent is coated on the combination face  21  of the additional component  20 . Besides, a water-based treating agent is also allowed to be applied according to different combination between the material of the additional component  20  and the sole material. After the coating of the facial process layer  22  upon the combination face  21 , the combination face  21  of the additional component  20  undergoes a drying process to be modified. In an embodiment of the present invention, the facial process layer  22  is dried in a temperature between 50 to 80 Celsius degrees for 3 to 5 minutes for completing the facial modification of the combination face  21 . 
     In the gumming step S 2 , a gum layer  23  is disposed on the combination face  21  which is provided with the facial process layer  22 . In an embodiment of the present invention, the gum layer  23  is formed of material selected from polyurethane, polymethylmethacrylate, or epoxy glue, which is coated or sprayed upon one face of the facial process layer  22 . In an embodiment of the present invention, the gum layer  23  is dried in a temperature between 50 to 80 Celsius degrees for 3 to 5 minutes for completing the gum coating process. 
     In the in-mold positioning step S 3 , as shown by  FIG. 4 , after the gumming process, the facial processed additional component  20  is placed in a mold  30  to be positioned therein, while the combination face  21  is prevented from contacting the inner wall of the mold  30  as much as possible. Therefore, the facial process layer  22  and the gum layer  23  of the additional component  20  do not internally pollute the mold  30 . 
     In the injection molding step S 4 , the sole material of the sole body  10  is injected in the mold  30 . The hot-melted sole material flows along the structural shape of the mold  30 , such that the sole material is combined with the gum layer  23  on the combination face  21  of the additional component  20 . After a vulcanization and cooling process, the sole material is solidified into the sole body  10 . At the meantime, the facial process layer  22  and the gum layer  23  are disposed between the combination face  21  of the additional component  20  and the sole face  11  of the sole body  10 , and the gum layer  23  is combed between the facial process layer  22  and the sole face  11  of the sole body  10 , such that the additional component  20  is gummed on the bottom or the peripheral portion of the sole body  10 , forming the composite shoe sole  100 . For example, as shown by  FIG. 5 , the sole face  11  is positioned on the bottom portion of the sole body  10 . When the additional component  20  is disposed on the sole face  11 , the additional component  20  has a base portion  24  and a plurality of convex portions  25  disposed on the base portion  24 . The combination face  21  is disposed on the inner lateral side of the base portion  24 , and the convex portions  25  are disposed on the outer lateral side of the base portion  24 . In an embodiment of the present invention, the convex portions  25  are provided in an amount of four, and are averagely distributed on the outer lateral side of the base portion, such that the additional component  20  forms a shoe cleat structure. As shown by  FIG. 7 , the sole face  11  is positioned around the sole body  10 , and the additional component  20  has a base portion  24  mounted around the sole face  11  of the sole body  10  to form a protection pad structure thereon. 
     Notably, when the additional component  20  is formed of a material identical to the sole material, based on the fact that the same material have identical properties, the facial modifying process S 1  in the manufacturing method is allowed to be skipped, such that the manufacturing method accordingly begins from the gumming step S 2  to the injection molding step S 4 , thus shortening the overall time cost and improving the manufacturing efficiency. 
     With such configuration, the additional component  20  and the sole material are combined to form the composite shoe sole  100 . During the manufacturing process, the additional component  20  undergoes the facial processing in advance and is placed into the mold  30  afterward, reducing the possible pollution of the treating agent upon the mold  30  and increasing the yield rate of the composite shoe sole  100 . Also, such facial processing of the additional component  20  outside the mold  30  not only reduces the time cost of the manufacturing process, but also improves the safety during the manufacturing process. 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.