JP2009034970A - Molded article and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molded article wherein a surface which causes peeling of plating is limited to a surface where a gates is connected, and to provide an electronic device having the molded article. <P>SOLUTION: The molded article 1 is plated after forming by injection molding. The molded article 1 has a main part 2 and a pedestal 6 which projects from a rear surface 2a of the main part 2, and is provided with a gate 44 wherethrough a thermoplastic resin is introduced during the injection molding. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a molded article formed by injection molding, and particularly to a molded article that is plated after injection molding.

  2. Description of the Related Art Conventionally, a method is known in which a shutter button of an electronic device such as a digital camera is injection-molded and then plated for rust prevention or the like. Patent Document 1 proposes that when a molded product is immersed in a plating solution, a jig for holding the molded product is attached to a spool runner formed at the time of injection molding, and the gate is separated from the molded product after plating. . Since the gate is also plated when the molded product is plated, the gate is cured. For this reason, it is difficult to cut the gate with a nipper, and the gate is manually bent several times.

FIG. 7 is a perspective view showing a state in which the four molded products 1 are attached to the spool runner 42 via the gate 44 and plated.
JP-A-6-328514

  However, if the gate 44 is cut manually by bending it several times in FIG. 7, not only the back surface 2a but also the side surface 2b of the molded product 1 on which the gate 44 is formed as shown in FIG. Normally, the surface of the molded product 1 to which the gate 44 is connected (the back surface 2a in FIG. 8) is not exposed to the outside when mounted on an electronic device (not shown). . However, since the other surfaces (for example, the side surface 2b and the surface 2c) are exposed to the outside, if there is plating peeling P, it becomes a defective product and the yield decreases.

  The present invention relates to a molded product and an electronic device that limit a surface on which plating peeling occurs to a surface to which a gate is connected.

  The molded product as one aspect of the present invention is a molded product that is formed by injection molding and then plated, and has a main body portion and a pedestal that protrudes from one surface of the main body portion, and the pedestal is formed by the injection molding. And is connected to a gate into which a thermoplastic resin is introduced.

  Further objects and other features of the present invention will become apparent from the preferred embodiments described below with reference to the accompanying drawings.

  ADVANTAGE OF THE INVENTION According to this invention, the molded article and electronic device which limit the surface where plating peeling generate | occur | produces to the surface where the gate is connected can be provided.

  Hereinafter, a method for manufacturing a digital camera 100 as an electronic apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a flowchart of a method for manufacturing the digital camera 100. 2A is a perspective view of the digital camera 100, and FIG. 2B is a partially enlarged perspective view of FIG. 2A. The manufacturing method of the digital camera 100 includes a forming step 1100, a plating step 1200, a gate separation step 1300, and a mounting step 1400. Among these, steps 1100 to 1300 function as a method for manufacturing the molded product 1. The molded product 1 is configured to be mountable on the digital camera 100.

  In the molding step 1100, a thermoplastic resin is introduced into the mold from the gate and a molded product is formed by injection molding. FIG. 3 is a schematic partial cross-sectional view of the mold 10. The mold 10 includes a fixed mold 20 and a movable mold 30, both of which can be clamped and opened on the mold dividing surface L. The fixed mold 20 and the movable mold 30 form a cavity C. The thermoplastic resin is introduced into the cavity C from the fixed mold 20 side through the sprue 40, the runner 42, and the gate 44 that are flow paths of the thermoplastic resin (molten resin). 46 is a slide core. The slide core 46 is provided for undercut processing. The undercut process refers to a process of removing the undercut part because a molded product cannot be taken out in the mold opening direction D after molding if there is a structure biting into the molded product. In FIG. 3, the slide core 46 is an undercut part.

The cavity C includes a cavity C ₁ formed by the fixed mold 20 and cavities C ₂ and C ₃ formed by the movable mold 30. Among these, the cavities C ₁ and C ₂ form the main body ₂ of the molded product 1. The main body 2 is a component necessary to function as a member of the digital camera 100 when the molded product 1 is mounted on the digital camera 100 shown in FIG. On the other hand, the cavity C ₃ constitutes a pedestal 6 formed in the main body 2 of the molded product 1, and the pedestal 6 is not a necessary component for functioning as a member of the digital camera 100. A gate 44 is connected to the base 6. In other words, the cavity C ₃ One end C _{2 a} along the mold-opening direction D is connected to the mold split surface L, and the other end C _{2 b} is connected to the gate 44 of the thermoplastic resin is introduced. Part in the cavity C ₃ by the slide core 46 as undercut is defined.

  After the mold 10 is clamped, a thermoplastic resin is introduced from the gate 44. Then, mold opening and undercut processing are performed. The slide core 46 is slid in a direction perpendicular to the paper surface of FIG. 3 by the undercut process. Thereafter, the molded product 1 is taken out in the D direction.

  FIG. 4 is a schematic perspective view of the molded product 1 taken out. FIG. 4 can also be thought of as a perspective view of the structure after step 1200. In this embodiment, four molded articles are formed simultaneously. The molded product 1 includes a main body 2 and a base 6 formed on the back surface (one surface) 2a of the main body 2.

  The main body 2 has a back surface 2a, a side surface 2b, and a front surface 2c, and has a substantially cylindrical shape. A part of the side surface 2b and the surface 2c are portions exposed to the outside when mounted on the digital camera 100. On the back surface 2a, four positioning members 3, a pair of engaging portions 4, and a central support column 5 are formed. The upper surface 3 a of the positioning member 3 determines the position of the main body 2 in the Z direction with respect to the digital camera 100. The Z direction is a direction perpendicular to the back surface 2 a of the main body 2. The engaging portion 4 has the flange portion 4 a at the tip thereof fitted in an engaging groove (not shown) of the digital camera 100 to fix the main body portion 2 to the digital camera 100. The support 5 is inserted into an engagement hole (not shown) of the digital camera 100 to maintain the posture of the main body 2 with respect to the digital camera 100.

  The pedestal 6 has a thin quadrangular prism shape and protrudes from the back surface 2 a of the main body 2. FIG. 5 is an enlarged perspective view of one molded product 1 shown in FIG. The pedestal 6 has a surface 6a and four side surfaces 6b perpendicular to the surface 6a, and the end of the substantially rectangular gate 44 is connected within the range of the surface 6a. The height K in the Z direction from the back surface 2a of the front surface 6a of the base 6 is set to 0.2 mm or more and below the height from the back surface 2a of the upper surface 3a of the positioning member 3. The reason why it is “0.2 mm or more” is that if the height is too low, plating peeling P described later may propagate from the side surface 6b of the base 6 to the back surface 2a. “Below the height from the back surface 2a of the top surface 3a of the positioning member 3” is that the position of the main body 2 in the Z direction with respect to the digital camera 100 exceeds the height from the back surface 2a of the top surface 3a of the positioning member 3 Because it collapses. In this embodiment, since the pedestal 6 is arranged in a space that is vacant on the main body 2 between the back surface 2a of the main body 2 and the upper surface 3a of the positioning member 3, the digital camera can be provided by arranging the pedestal 6. No increase in size of 100.

  The plating step 1200 is performed by immersing the molded product 1 in a plating solution. The structure shown in FIG. 4 is immersed in a plating solution and subjected to electroless plating. At this time, the runner 42 functions as a holding unit that holds the molded product 1. This makes it possible to attach a plurality of molded products at a time during molding, as compared with a method of individually mounting each molded product 1 on a jig, thereby improving production efficiency.

  The gate separation step 1300 separates the gate 44 from the base 6. As shown in FIG. 5, with the plating step 1200 completed, the gate 44 is cut by manually bending the runner 42 in the direction of arrow R several times with respect to the molded product 1. Of course, the molded product 1 may be bent with respect to the runner 42.

  FIG. 6 is an enlarged perspective view showing a state after the structure shown in FIG. Plating peeling P occurs with the separation of the gate 44, but the range of the plating peeling P is limited to the surface 6a of the pedestal 6 and does not propagate from the side surface 6b of the pedestal 6 to the back surface 2a and side surface 2b of the main body 2. . In other words, in this embodiment, the surface where the plating peeling P occurs is limited to the surface 6a to which the gate 44 is connected. As a result, when the molded product 1 is mounted on the digital camera 100, the plating peeling P does not reach the portion exposed to the outside (for example, the side surface 2b of the main body 2). Note that the gate 44 is an outlet (hole) from which the thermoplastic resin is injected from the runner 42, but the portion of the plating peeling P after the gate 44 is separated may be referred to as a gate. In other words, the molded product 1 plated after the injection molding shown in FIG. 6 has a structure in which the gate 44 is provided on the surface 6 a of the base 6.

  In mounting step 1400, the molded product 1 is mounted on the main body of the digital camera 100. The state after mounting is shown in FIGS. 2 (a) and 2 (b). In this embodiment, the molded product 1 functions as a shutter button of the digital camera 100. Since there is no plating peeling P on the surface of the shutter button, the yield is improved.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist thereof.

It is a flowchart of the manufacturing method of a digital camera (electronic device). 2A is a perspective view of the digital camera shown in FIG. 1, and FIG. 2B is a partially enlarged perspective view of FIG. 2A. It is a schematic fragmentary sectional view of the metal mold | die used for step 1100 shown in FIG. It is a perspective view of the molded product which passed through step 1100 or 1200 shown in FIG. It is an expansion perspective view of the one molded article shown in FIG. FIG. 6 is a perspective view showing a state after the structure shown in FIG. 5 has undergone step 1300 shown in FIG. 1. It is a perspective view for demonstrating the problem of the conventional molded article. It is an expansion perspective view which shows the state which isolate | separated the gate in the one molded article shown in FIG.

Explanation of symbols

1 Molded product (shutter button)
2 Main body 3 Positioning member 3a Upper surface 6 Base 100 Digital camera (electronic device)

Claims (3)

In a molded product that is plated after being formed by injection molding,
A molded product comprising a main body portion and a pedestal protruding from one surface of the main body portion, and a gate into which a thermoplastic resin is introduced in the injection molding is provided on a surface of the pedestal. The molded product can be mounted on an electronic device, and further has a positioning member on the one surface of the main body for positioning the main body with respect to the electronic device when mounted on the electronic device.
2. The molded product according to claim 1, wherein a height of the main body portion of the pedestal from the one surface is 0.2 mm or more and a height of the positioning member from the one surface of the main body portion.   An electronic apparatus comprising the molded product according to claim 1.