Patent Publication Number: US-2023158868-A1

Title: Overmold bracket with open mounting surface on bracket

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a PCT International Application and claims benefit of U.S. Provisional Patent Application No. 63/011,596, filed Apr. 17, 2020. The disclosures of the above application are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an overmold structure with at least one open mounting and/or routing surface on the structure and process for manufacturing same. 
     BACKGROUND OF THE INVENTION 
     Compression Limiters or rivet nuts are often used to help create a robust threaded fastener joint that would otherwise creep and loosen if a plastic panel would be compressed in a typical threaded fastener joint. Compression limiters and rivet nuts, however, add cost and complexity to a design and to the assembly process. Conventional designs and methods have used mechanical fasteners like compression limiters, and rivet nuts or/and brackets that may not be over molded. 
     These cause problems with packaging, space, cost, complexity and quality, etc. 
     Thus, it is an objective of the present invention to eliminate the need for compression limiters or rivet nuts to reduce complexity, reduce cost, reduce possibility of poor assembly, reduce assembly time, reduce weight, etc. 
     Another known problem is that tethers are often times used on items such as thermoplastic (“TP”) Liftgates, and attachments can add extra costs and assembly time and complexity. Some conventional designs use mechanical fasteners and brackets that do not get over molded. 
     Thus, it is an objective of the present invention to maintain the overmolding of bracket advantage, and maintain an open hole for tether routing to reduce complexity, reduce cost, reduce possibility of poor assembly, reduce assembly time, reduce weight, etc. 
     SUMMARY OF THE INVENTION 
     The present invention eliminates the need for compression limiters or rivet nuts to reduce complexity, reduce cost, reduce possibility of poor assembly, reduce assembly time, reduce weight, etc. 
     This invention allows the overmolding of the bracket and maintains a lower cost fastener joint that does not require extra components or special components. 
     The injection mold protects and maintains an opening through the molding operation, and, optionally, through open to die tip tool direction, or through tool action such as a lifter, and this open surface is the mounting surface for items such as hinges, ball stud, bracket, etc. 
     Preferably, the bracket mounting surface is maintained through the over molding process. 
     In addition, according to aspects of the present invention putting holes in metallic reinforcements for tether routing creates a more efficient design. Overmolding metallic brackets creates an efficient method of combining the bracket and molded panel; thus, overmolding the bracket and maintaining the hole for tether routing creates an even more efficient and cost-effective design. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG.  1    is a rear elevation view of an exemplary liftgate assembly, in accordance with aspects of the present invention; 
         FIG.  2    is a cross section taken at C-C of  FIG.  1   , in accordance with the present invention; 
         FIG.  3    is an enlarged cross section taken at ‘B’ of  FIG.  2   , in accordance with the present invention; 
         FIG.  4    is an enlarged view taken at ‘C’ of  FIG.  3    including a hinge, according to aspects of the present invention; 
         FIG.  5    is an enlarged cross section at ‘A’ of  FIG.  2   , including a hinge area environment of use, according to aspects of the present invention; 
         FIG.  6    is a cross section taken at ‘B-B’ of  FIG.  1   , including a ball stud attachment environment of use, in accordance with the present invention; 
         FIG.  7    is a top plane view of a bracket, according to aspects of the present invention; 
         FIG.  8    is a perspective view of the bracket of  FIG.  7   ; 
         FIG.  9    is a perspective view of the bracket of  FIG.  7   ; 
         FIG.  10    is a side elevation view of the bracket of  FIG.  7   ; 
         FIG.  11    is a perspective view of an exemplary liftgate panel, including at least one tether, in accordance with the present invention; 
         FIG.  12    is a rear elevation view of an exemplary liftgate panel, including exemplary tether routing placement in an environment of use, in accordance with the present invention; and 
         FIG.  13    is a cross section taken at ‘A-A’ of  FIG.  1   , depicting a tether routing aperture with an overmolded bracket, in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     Referring to  FIGS.  1 - 6    generally, there is illustrated an exemplary liftgate assembly indicated generally at  10 , including an overmold bracket with at least one mounting surface on the bracket and method for making same, in accordance with the present invention. There is provided at least one overmold bracket with at least one open mounting surface on the bracket. The open mounting surface on the bracket can provide for at least one thermoplastic liftgate hardware attachment. 
       FIGS.  2 - 5    depict a cross section at a hinge area taken at C-C of  FIG.  1   , e.g., at least one of a pair of oppositely-disposed hinge portions. By way non-limiting examples, a liftgate hinge, rear window hinge, etc. 
       FIG.  6    depicts a cross-section taken at B-B of  FIG.  1    at a ball stud attachment, e.g., one of oppositely-disposed bottom corner regions of a rear window, with a ball stud attachment depicted generally at  20 . 
     Referring more particularly to  FIGS.  2 - 5   , there is provided overmold and maintaining of an open footprint for direct hardware attachment. One benefit is a lower cost liftgate. Generally, the present invention overmolds and maintains a predetermined open footprint. Typically, the overmold portion, indicated generally at  12  is provided and an open footprint maintained, indicated generally at  14 , for direct hardware attachment, indicated generally at  16 , e.g., hinge  18 , ball stud  20 , hat bracket, latch fasteners, and any other bracket-type mounting, without the added costs that would be associated with rivet nuts or compression limiters, which the present invention eliminates, in accordance with aspects of the present invention. Optionally, weld nuts  24  (e.g., see  FIG.  6   ) can be used as needed and included with the overmolding bracket sub assembly; the overmolded bracket sub-assembly indicated generally at  22 . Preferably, at least one aperture  26  is provided through at least one bracket  28 , e.g., that is a latch bracket such as indicated generally at  34 , and overmold indicated generally at  30 , for operably connecting at least one attachment  16 , e.g., hinge, ball stud, hat bracket, latch fastener, and any other bracket type mounting, without the added cost of rivet nuts or compression limiters, and/or operably connecting at least one attachment that is a tether  36 , etc. The at least one aperture  26  can, by way of non-limiting example, be an opening. The at least one aperture  26  can, by way of non-limiting example, be a hole. 
     Referring generally to  FIGS.  1 - 13   , according to aspects of the present invention, at least one injection mold protects and maintains the at least one aperture  26  throughout the molding operation, e.g., at least one liftgate panel  32  molding, and, preferably, through open to die tip tool direction, or through a tool action such as a lifter, or any other suitable process, and this open surface is the mounting surface for items such as hinges, ball stud, bracket, etc. and any combinations thereof. The present invention operably maintains the predetermined bracket mounting surface through the predetermined over molding process. 
     The present invention allows the overmolding of the at least one bracket  28  and maintains a lower cost fastener joint that does not require extra components or special components. Thus, the present invention eliminates the need for mechanical fasteners such as compression limiters or rivet nuts to thereby reduce complexity, reduce cost, reduce possibility of poor assembly, reduce assembly time, reduce weight. 
     The at least one overmold bracket  28  is selected from the group consisting of: at least one latch plate, at least one liftgate striker, at least one D-Pillar reinforcement, at least one shock plate, at least one strut plate, at least one hinge plate, at least one upper horizontal reinforcement, at least one side reinforcement, at least one vertical reinforcement, at least one corner liftgate reinforcement, at least one metal bracket, at least one steel bracket, at least one fiber reinforced molded bracket, and any combinations thereof. 
     The at least one predetermined liftgate attachment  16  is selected from the group consisting of: at least one hinge, ball stud, hat bracket, latch fasteners, weld nuts, bracket mounting, tether, and any combination thereof. 
     Referring more particularly to  FIGS.  6 - 13    generally, there is illustrated an exemplary liftgate assembly indicated generally at  10 , including an overmold  30  and at least one aperture  26  maintained for tether routing. There is provided at least one aperture (e.g., opening or hole) in at least one overmolded bracket  28 , e.g, reinforcement bracket, metal bracket, fiber reinforced bracket, etc. In accordance with aspects of the present invention, there is provided the creating of at least one aperture  26 , preferably, a plurality of holes, in at least one reinforcing bracket  28  for low cost tether routing of at least one tether  36  and maintaining the aperture  26  even with the bracket  28  over molding. At least one open mounting surface is provided. Preferably, a flange portion, indicated generally at  38 , has at least one overmolded bracket  28 . The over mold flange is provided and predetermined tool action produces the at least one aperture  26 . Optionally, a secondary operation produces at least one aperture  26 , if required. Optionally, at least one additional tether is provided or at least one opening created and maintained for at least one wire harnesses routing, substantially as set forth previously. 
     Referring to  FIGS.  1 - 13    generally, according to aspects of the present invention, there is created at least one aperture  26  in the stamping that is maintained in the molding operation, and, alternatively, through tool action such as a lifter, and/or at least one aperture is added post overmolding, as a secondary operation. The at least one aperture  26  (e.g., hold, opening, slit, etc) is maintained for tether  36  routing with the over molding process. 
     Putting apertures  26  in metallic reinforcements for tether routing creates a more efficient design. Overmolding metallic brackets creates an efficient method of combining the bracket  28  and molded liftgate panel; thus, overmolding the bracket and maintaining the aperture for tether routing creates an even more efficient and cost effective design. 
     The present invention maintains the overmolding of bracket advantage, and maintains an open aperture for tether routing. Thus, the present invention reduces complexity, costs, the chances of poor assembly and is more efficient and cost effective. 
     The liftgate  10  includes at least one panel  32 , preferably, at least one inner panel  32  and at least one outer panel  33 , most preferably at least one inner panel, at least one upper outer panel with show, Class-A surface, and at least one lower outer panel with show, Class-A surface. The liftgate is adapted to couple a rear window  40 , e.g., by adhesive  42 . The panel(s)  32  are predetermined materials suitable for strength and weight considerations, etc, e.g., composite, SMC, sheet metal composition, thermoplastic, etc. The reinforcements are preferably metal, e.g., steel, but any other suitable materials are contemplated, e.g., lighter weight metals, aluminum, plastics, carbon reinforced thermoplastics, etc. and any combinations thereof, depending on the application without departure from the present invention. 
     It is understood that while the present invention is adapted for a liftgate assembly as shown, the present invention is adaptable for any alternative assembly, e.g., door assembly, tailgate assembly, bumber, fender, roof top, rocker panel, etc, depending on the application without departure from the scope of the present invention. It is understood that the bracket is adaptable for attachment to any predetermined part, e.g., reinforcement, strut bracket, hinge bracket, plate bracket, pillar reinforcement, or any other part and combinations thereof, etc., depending on the application without departure from the scope of the present invention. While a metallic reinforcement is described it is understood that any alternative suitable material is contemplated, e.g., metal, reinforced composite, etc., is contemplated depending on the application without departure from the scope of the present invention. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.