Abstract:
Electronic device comprising frame and trim. Trim wrapped around at least three sides of the frame. Trim comprising an outer piece and an inner assembly. Outer piece of substantially continuous flexible tactile material comprising a substantially elongate first side portion, a substantially elongate second side portion substantially parallel to the first side portion, and at least one substantially elongate cross portion connecting the first and second side portions. The inner assembly comprising a substantially rigid first side inner piece substantially coextensive with the outer piece first side portion; a substantially rigid second side inner piece substantially coextensive with the outer piece second side portion; and at least one substantially rigid inner cross piece. Each cross piece substantially coextensive with the short dimension of the outer piece cross portion, and shorter than the long dimension of the outer piece cross portion, thereby creating at least one gap in the inner assembly.

Description:
FIELD OF THE DISCLOSURE 
       [0001]    The technology relates to molded items that, in an installed configuration, have at least on feature that impedes withdrawal from the mold. The technology further relates to processes and materials for manufacturing such items. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0002]    Implementations of the present technology will now be described, by way of example only, with reference to the attached Figures, wherein: 
           [0003]      FIG. 1  illustrates a mobile communication device configured; 
           [0004]      FIG. 2  is an exploded view of a mobile communication device; 
           [0005]      FIG. 3  illustrates a first side piece, a second side piece, and a first cross piece of implementations of the technology. 
           [0006]      FIG. 4  illustrates an outer piece of implementations of the technology. 
           [0007]      FIG. 5  illustrates an implementation of an assembly of the technology. 
           [0008]      FIG. 6  illustrates an implementation of an assembly of the technology as extracted from a mold. 
           [0009]      FIG. 7  illustrates methods of the technology. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    Reference will now be made in detail to example implementations of the technology. Each example is provided by way of explanation of the technology only, not as a limitation of the technology. It will be apparent to those skilled in the art that various modifications and variations can be made in the technology without departing from the scope or spirit of the technology. For instance, features described as part of one implementation can be used on another implementation to yield a still further implementation. Thus, it is intended that the present technology cover such modifications and variations that come within the scope of the technology. 
         [0011]    Referring to  FIG. 1  and  FIG. 2  as an example context of the technology, a mobile communication device  300  is illustrated. The mobile communication device  300  can comprise a display  322  located above a keyboard  332  suitable for accommodating textual input to the mobile communication device  300 . As shown, the mobile communication device  300  can be of uni-body construction, also known as a “candy-bar” design. In other implementations, the mobile communication device  300  can be a flip-type phone or a slider-type as well. 
         [0012]      FIG. 2  illustrates some typical components that can be found in the assembly of the mobile electronic device  300 . A support frame  101  cab constitute a base for many other components of the mobile communication device  300 . The assembly can interconnect right side element  105 , left side element  106 , top element  107 , and bottom element  108  with the support frame  101 . Elements  106 - 108  typically can be substantially rigid. For example, elements  106 - 108  can be formed of polycarbonate material. Such material can provide protection and strength to the support structure of the mobile communication device  300 . Such material also can draw heat away from the interior of the mobile communication device through heatstaking Further, the material can be used to frame i) buttons (e.g.,  130 ,  131 ,  132 ,  133 ) that can be attached to switches (not shown in  FIG. 2 ), ii) input/output ports (for example, Universal Serial Bus (USB) port  330 ), and iii) jacks (for example, audio jack  140 ) via apertures in the elements. 
         [0013]    It is typical to form elements such as  105 - 108  via injection molding. Injection molding is a manufacturing process for producing parts from both thermoplastic and thermosetting plastic materials. Material is fed into a heated barrel, mixed, and forced into a mold cavity where the material cools and hardens to the configuration of the mold cavity. After a product is designed, usually by an industrial designer or an engineer, molds are made by a moldmaker (or toolmaker) from metal, usually either steel or aluminium, and precision-machined to form the features of the desired part. Injection molding is widely used for manufacturing a variety of parts, from the smallest component to entire body panels of cars. 
         [0014]    Injection molding is used to create many things such as wire spools, packaging, bottle caps, automotive dashboards, pocket combs, and most other plastic products available today. Injection molding is the most common method of part manufacturing. Injection molding is useful for producing high volumes of the same object. Some advantages of injection molding are high production rates, repeatable high tolerances, the ability to use a wide range of materials, low labor cost, minimal scrap losses, and little need to finish parts after molding. Some disadvantages of this process are expensive equipment investment, potentially high running costs, and the need to design moldable parts. 
         [0015]    Most polymers may be used, including all thermoplastics, some thermosets, and some elastomers. In 1995 there were approximately 18,000 different materials available for injection molding and that number was increasing at an average rate of 750 per year. The available materials are alloys or blends of previously developed materials meaning that product designers can choose from a vast selection of materials, one that has exactly the right properties. Materials are chosen based on the strength and function required for the final part but also each material has different parameters for molding that must be taken into account. Common polymers like Epoxy and phenolic are examples of thermosetting plastics while nylon, polyethylene, and polystyrene are thermoplastic. 
         [0016]    The edges of mobile communication device  300  present a substantially discontinuous and substantially hard surface to a user. As evident in  FIG. 1  (showing a hand touching the sides of mobile communication device  300 ) and  FIG. 2  (showing buttons on the top and both sides of mobile communication device  300 ), the mobile communication device  300  may be held by the sides, and buttons, e.g.,  130 ,  131 , at the top of the mobile communication device  300  may be engaged. Further the apertures for buttons, for example, apertures through top element  107 , can present openings for ingress of fluids and particles. Further, the apertures can expose the buttons, the ports, and the jacks to the possibility of being inadvertently becoming detached, for example, by being pried loose from the mobile communication device. 
         [0017]    The discontinuous hard tactile experience can be a disadvantage not only from an aesthetic perspective, but also from a functional perspective. For example, the hard surface may be more difficult to grasp securely. In addition, the possibility for ingress of fluids and particles presents another functional disadvantage to the use of a discontinuous hard tactile surface. Further, the possibility for device components becoming detached can be seen as a disadvantage in the design of mobile communication device  300 . 
         [0018]    One approach to addressing the discontinuous nature of substantially rigid elements  105 - 107  (and, in the alternate, bottom  108 ) is to form at least two adjacent elements as a single continuous element. However, this approach can present manufacturing disadvantages. For example, a single combination of adjacent elements from among elements  105 - 107  will typically include at least one feature, e.g., an undercut, which may impede withdrawal of the combined part from a mold. In another alternative, elements  105 - 108  can be formed in a single substantially rigid combination. But that approach presents the same disadvantage. While technology such as sliders can be used to facilitate molding of parts with features such as undercuts, these techniques typically present drawbacks such as increased manufacturing cost and complexity. Further such techniques result in the appearance of undesirable traits such as witness lines and seams in the part. Further yet, such an approach leaves disadvantages cited earlier such as the hard nature of the surface, the possibility for ingress of fluids and particles, and the possibility for device components to become detached unaddressed. 
         [0019]    Implementations of the present technology coat at least two adjacent elements from among, e.g.,  105 - 108 , with a flexible, softer, more tactile, material that presents a continuous surface. This continuous surface also is sufficiently flexible to allow switches to be activate through the softer material covering the apertures in the underlying substantially rigid pieces. Further, at least one gap is created between the underlying rigid pieces to allow for at least one molding configuration to facilitate manufacturing, and at least one installed configuration that can include features that would otherwise inhibit manufacturing. The assembly can be altered between the molding configuration and the installed configuration by flexing the flexible material. 
         [0020]    Referring to  FIG. 3 , a first side piece  360 , a second side piece  370 , and first cross piece  380  are shown. The first side piece  360  can be seen as analogous to the left side element  106  of  FIG. 2 . The second side piece  370  can be seen as analogous to the right side element  105  of  FIG. 2 . The first cross piece  380  can be seen as analogous to the top element  107  of  FIG. 2 . 
         [0021]    The first side piece  360  and second side piece  370  can be formed of substantially rigid material. For example, a polycarbonate material can be used to form first side piece  360  and second side piece  370 . In general, all kind of plastic materials can be used as long as the material has good adhesion to the substantially flexible outer component (to be described below). Each of first side piece  360  and second side piece  370  can have a substantially similar base thickness (e.g.,  361 ), short primary dimension (e.g.,  362 ), long primary dimension (e.g.,  363 ), an inner face (e.g.,  364 ), and an outer face (e.g.,  365 ). Each of first side piece  360  and second side piece  370  can have heat staking pins  366  and apertures  367  for access to switches, jacks, and input/output ports. In the illustrated implementation, each of first side piece  360  and second side piece  370  has a curved portion  368  corresponding to a transition between the side of a mobile communication device  300  and a back face or a front face of the mobile communication device  300 . The first side piece  360  can be curved along the first side piece  360  short dimension (i.e., with a radius center toward the other side piece in an installed configuration). The second side piece  370  can be curved along the second side piece short dimension (i.e., with a radius center toward the other side piece in an installed configuration). 
         [0022]    The first cross piece  380  can be formed from the same material as the first side piece  360  and the second side piece  370 , or the first cross piece  380  can be formed from any other suitable substantially rigid material having good adhesion to the outer component. Like the first side pieces  360  and the second side piece  370 , the first cross piece  380  can have a thickness that is less than the first cross piece  380  short primary dimension, and the first cross piece  380  can have a short dimension that is less than the first cross piece  380  long primary dimension, along with heat stakes  366 . In the illustrated implementation, In some implementations, the cross piece  380  can have apertures and guide features. In some implementations, a second cross piece can be included in the assembly between the side pieces, e.g., at the end distal from the first cross piece. 
         [0023]    Referring to  FIG. 4 , the outer piece  400  can be formed from substantially flexible material. For example, a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU) can be used to form the outer piece  400 . The illustrated outer piece  400  has a first side portion  410 , a second side portion  420 , and a first spanning portion  430 . In some implementations, the outer piece includes a additional spanning portions spanning the distance between the side pieces. For example, a second spanning portion can be located at the opposite end from spanning portion  430 . Though shown positioned at an end of the side pieces and substantially normal to the side pieces, the spanning portion(s) can be located at other points along the long primary dimension of the side pieces and can be oriented other than normal to one more side pieces. For example, spanning portions can be configured as diagonal pieces. The illustrated cross piece  400  has an inner face  440  and an outer face  450 . In the illustrated outer piece  400 , first side piece  410  and second side piece  420  each can include at least one button feature  460 . In the illustrated implementation, the second side piece  420  includes a port skirt feature  470 , and apertures  480 . 
         [0024]    A button feature  460  is shown in the implementation illustrated in  FIG. 4 . The button feature  460  can include region  460   a  on the outer piece outer surface. The button feature  460  also can includes post  460   b . Post  460   b  is in the direction of the outer piece inner surface  440 . Post  460   b  can activate a switch in the mobile communication device  300  when the outer piece outer surface  450  is depressed at the region  460   a.    
         [0025]    Referring to  FIG. 5 , an implementation of an assembled configuration  500  of a trim assembly of the technology in an installed orientation is illustrated. First side piece  360 , second side piece  370 , and first cross piece  380  are shown positioned abuttingly “inside” (i.e., closer to the interior of a mobile communication device  300  that the piece can be used in) outer piece  400  with the edges of the respective pieces substantially aligned. The example of  FIG. 5  includes reference numerals to various aspects of the pieces  360 ,  370 ,  380 ,  400  described elsewhere herein. 
         [0026]    The outer piece outer face  450  can form the outer face of the assembled configuration  500 . The substantially rigid inner faces of the first side piece  360 , the second side piece  370 , and the first cross piece  380  can form part of the inner face of the assembly. The remaining part of the inner face of the assembly can be formed by segments,  430   a  and  430   b , of the substantially flexible outer assembly spanning portion inner face  430 . While in the illustrated implementation the flexible regions, region  430   a  and region  430   b , of the assembly  500  can be disposed substantially symmetric about the first cross piece  380 , other implementations have only a single exposed flexible region, or multiple exposed flexible regions disposed symmetrically or asymmetrically. 
         [0027]    In the illustrated configuration, the substantially flexible outer piece  400  can be pressed at region  460   a  as described above to activate corresponding switches in a mobile communication device  300  when the assembly is installed on the mobile communication device  300 . Also, apertures, e.g.,  480  can accept interface structures (e.g., USB connectors) from outside the mobile communication device  300  for connection to a device port(s) exposed through the aperture. In some implementations, the apertures can have removable covers (for example made of the same material as the outer piece) flexibly attached to the outer piece  400 . Further, heat staking pins  366  can be used to attach the assembly to a mobile communication device  300  and facilitate the conduction of heat from the interior of the mobile communication device toward the exterior of the mobile communication device. 
         [0028]    Some implementations of the assembly include a second spanning portion of the outer piece and a second cross piece between the respective side pieces and side portions. 
         [0029]    In the illustrated implementation, the cross piece  380  is substantially centered on the outer piece spanning portion  430 , exposing flexible regions  430   a  and  430   b . In other implementations, placement of cross pieces (e.g.,  380 ) can create one, or more than two, regions of flexibility in the assembly, and can create asymmetrical arrangements of such regions. 
         [0030]    Referring to  FIG. 6 , a molding configuration  600  of the assembly is shown. Several features identified in  FIG. 1  through  FIG. 5  are indicated in  FIG. 6  as reference points. Substantially flexible regions  430   a  and  430   b  are bent generally about the y-axis when compared to the installed configuration  500 . In the molding configuration  600 , the assembly orients most features substantially in the direction of the z-axis, facilitating removal of the assembly from a mold cavity. 
         [0031]    Referring to  FIG. 7 , methods  700  of the technology are illustrated. First, the assembly is formed, e.g., via a 2-shot molding process, in a molding configuration  710 , i.e., with flexible regions  430   a  and  430   b  flexed to facilitate removal from the mold cavity. Next, the assembly is configured  720  to an assembled configuration  500  on the mobile communication device  300 . 
         [0032]    In summary, using the flexible nature of certain sections of the outer piece, the trim assembly is molded in a molding configuration such that the elements of the assembly are oriented for substantially unidirectional withdrawal from the mold cavity after the second shot. This reduces, if not eliminates, the need for technology such as sliders; giving no slider-caused witness lines. This approach is possible, at least in part because of flexible portions of the outer piece.