KR102593170B1 - Manufacturing method of exterior cover of electronic device - Google Patents

Abstract

The method of manufacturing an electronic device exterior cover of the present invention includes a mold design step of designing an injection mold in which the shape of the final molded product is reverse-engineered so that the inner and outer sides are swapped in a form corresponding to the shape of the object to be covered; A first molding step of manufacturing a first molded product by injection molding an elastic raw material using the reverse engineered injection mold; and a secondary molding step of manufacturing a final molded product by turning over the first molded product so that the inside and outside of the first molded product manufactured through the first molding step are swapped. There is no parting line caused by an injection mold on the outer surface of the exterior cover, and accurate shapes can be manufactured without deformation of the hole shape and undercut shape. Manufacturing of the exterior cover is easy, reducing manufacturing man-hours and manufacturing costs. This is about a method of manufacturing an external cover for an electronic device.

Description

{Manufacturing method of exterior cover of electronic device}

The present invention relates to a method of manufacturing an exterior cover that is attached to the outside of an electronic device to protect the electronic device.

In order to protect electronic devices or electronic components mounted inside an electronic device from external shock and to protect the external case of the electronic device from friction, an external cover is generally mounted on the outside of the case of the electronic device.

For example, a conventional exterior cover for an electronic device undergoes primary molding to manufacture the overall shape of the housing 1 through injection molding using a mold as shown in Figure 1. Thereafter, as shown in FIGS. 2 and 3 , the manufacturing of the exterior cover can be completed by forming a plurality of holes 2 penetrating the outer and inner peripheral surfaces of the housing 1 for heat dissipation of the electronic device through post-processing.

However, when the exterior cover manufactured using this manufacturing method is injection molded, parting lines (PL), which are marks caused by a separate mold, are generated in at least two places on the outer surface of the molded product, making the exterior cover not have a smooth appearance. In addition, since post-processing of multiple holes generally involves machining thousands of micro holes, there is a disadvantage in that manufacturing costs increase due to increased work man-hours and time.

KR 20-1989-0008614 U (1989.05.29)

The present invention was created to solve the problems described above, and the purpose of the present invention is to provide a method of manufacturing an electronic device exterior cover that can be smoothly formed without a parting line caused by an injection mold on the outer surface of the exterior cover. It is done.

In addition, it is possible to manufacture an exterior cover with an accurate shape by preventing deformation or tearing of the hole and undercut shape of the exterior cover, and it is a method of manufacturing an electronic device exterior cover that can reduce manufacturing man-hours and manufacturing costs by making it easy to manufacture the exterior cover. is to provide.

The method for manufacturing an electronic device exterior cover of the present invention to achieve the above-mentioned object is to design an injection mold with the shape of the final molded product reverse-engineered so that the inner and outer sides are changed in a form corresponding to the shape of the object to be covered. Mold design stage; A first molding step of manufacturing a first molded product by injection molding an elastic raw material using the reverse engineered injection mold; and a secondary molding step of manufacturing a final molded product by turning over the first molded product so that the inside and outside of the first molded product manufactured through the first molding step are swapped. may include.

In addition, in the mold design step, the reverse engineered injection mold is formed in a shape corresponding to the shape in which a plurality of through holes penetrating the inner and outer surfaces of the housing of the primary molded product to be molded are arranged along the circumferential direction. It can be.

In addition, in the mold design step, the reverse engineered injection mold includes a main core and a plurality of slide cores disposed adjacent to the outside of the main core and arranged adjacent to each other along the circumferential direction, and the plurality of slides Core pins of a shape corresponding to the through holes of the primary molded product are formed on the core, so that the housing of the primary molded product and a plurality of through holes can be formed simultaneously in the primary molding step.

Additionally, in the mold design step, the reverse engineered injection mold may be formed in a shape corresponding to the shape in which the undercut protrudes outward from the outer surface of the housing of the primary molded product to be molded.

In addition, grooves of a shape corresponding to the undercut of the primary molded product are further formed in each of the plurality of slide cores, so that the housing of the primary molded product, a plurality of through holes, and undercuts can be formed simultaneously in the primary molding step. .

Additionally, the plurality of slide cores may be formed of 12 or more.

In addition, the reverse engineered injection molding mold further includes a cam that drives the plurality of slide cores, and the plurality of slide cores are formed in two sets by forming the same group of slide cores that are adjacent to each other in the circumferential direction, After the primary molded product is injected and hardened in the primary molding step, one of the two sets of jaws retreats radially outwardly by driving the cam, and then the other jaw retreats radially outwardly. A plurality of slide cores can work.

Additionally, before the plurality of slide cores retreat radially outward, air can be injected into the gap between the main core and the slide core to separate the primary molded product from the injection mold.

Additionally, the primary molded product may have parting lines formed by a plurality of slide cores formed on the outside of the housing.

In addition, the electronic device exterior cover of the present invention is manufactured by the electronic device exterior cover manufacturing method described above, and a plurality of through holes are formed in the housing of the final molded product, and the parting line formed by the injection mold is formed in the housing of the final molded product. It may be formed to be located on the inner side of the housing and not on the outer side.

Additionally, an undercut may be formed in the housing of the final molded product, protruding radially inward from the inner surface.

The method of manufacturing an electronic device exterior cover of the present invention has the advantage of producing an accurate shape without a parting line caused by an injection mold on the outer surface of the exterior cover and without deformation of the hole shape or undercut shape.

In addition, the exterior cover is easy to manufacture, which has the advantage of reducing manufacturing man-hours and manufacturing costs.

Figures 1 to 3 are perspective views showing a conventional electronic device exterior cover and the process of manufacturing it.
Figures 4 to 6 are perspective views showing an electronic device, an exterior cover, and a state in which the exterior cover is coupled to the outside of the electronic device according to an embodiment of the present invention.
7 to 9 are a front cross-sectional view, a partial enlarged view, and a lower side view showing an injection mold for manufacturing an exterior cover of an electronic device according to an embodiment of the present invention.
Figures 10 and 11 are a perspective view and a cross-sectional view showing a primary molded product manufactured using an injection mold according to the present invention.
Figures 12 and 13 are a perspective view and a cross-sectional view showing a state in which the first molded product manufactured according to the present invention is turned over and the final molded product is completed.

Hereinafter, the method for manufacturing an electronic device exterior cover of the present invention having the above-described configuration will be described in detail with reference to the attached drawings.

Figures 4 to 6 are perspective views showing an electronic device, an exterior cover, and a state in which the exterior cover is coupled to the outside of the electronic device according to an embodiment of the present invention.

First, as shown, the electronic device exterior cover 20 manufactured by the electronic device exterior cover manufacturing method according to an embodiment of the present invention has, for example, a plurality of through holes penetrating the inner and outer peripheral surfaces of the housing 21 ( 22) is formed, so that heat dissipation of the electronic device can be smoothly achieved through the through holes 22. Here, the through hole 22 may be formed as a fine hole with a diameter of about 1.8 mm, and the number of through holes 22 may be approximately several thousand. Additionally, an undercut 23 may be formed at the top of the housing 21 in a form that protrudes radially inward from the inner peripheral surface. Therefore, when the electronic device 10 is covered and coupled with the electronic device exterior cover 20, the housing 21 surrounds the circumference of the electronic device 10 and the undercut 23 hangs on the top of the electronic device 10. Can be combined into shapes.

Figures 7 to 9 are front cross-sectional views, partial enlarged views, and lower side views showing an injection mold for manufacturing an exterior cover of an electronic device according to an embodiment of the present invention, and Figures 10 and 11 show an injection mold according to the present invention. It is a perspective view and a cross-sectional view showing the first molded product manufactured using the present invention, and Figures 12 and 13 are a perspective view and a cross-sectional view showing the state in which the first molded product manufactured according to the present invention is turned over and the final molded product is completed.

As shown, the method of manufacturing an electronic device exterior cover according to an embodiment of the present invention may largely include a mold design step, a primary molding step, and a secondary molding step.

The mold design stage is the stage of designing an injection molding mold in which the shape of the final molded product is reverse-engineered into a shape that corresponds to the shape of the electronic device to be covered, with the inside and outside changed. That is, in the mold design stage, unlike the shape of the final molded product to be manufactured by injection molding, the injection mold is designed and manufactured in a shape corresponding to the upside-down shape of the final molded product with the inner and outer sides changed in the shape of the final molded product. In other words, the reverse engineered injection mold can be designed to correspond to the primary molded product in which the inside and outside of the final molded product are changed. Here, the shape of the primary molded product 20a is formed with a plurality of through holes 22 penetrating the inner and outer surfaces of the housing 21, and the plurality of through holes 22 are formed along the circumference of the housing 21. Can be arranged along a direction. Additionally, an undercut 23 may be formed to protrude radially outward from the outer surfaces of the upper and lower ends of the housing 21. Therefore, in the reverse engineered injection mold, grooves and a plurality of core pins 510 of a shape corresponding to the shape of the first molded product may be formed to protrude. In more detail, the injection mold can be largely composed of an upper mold 100, a lower mold 200, a lower plate 300, a main core 400, a plurality of slide cores 500, and a stripper plate 700. and may further include a cam 600. The upper mold 100 and the lower mold 200 are arranged to face each other up and down, and the upper mold 100 can be moved in the vertical direction and then fixed in position, and the lower mold 200 is fixed to the die. It can be. In addition, a lower plate 300, a main core 400, a plurality of slide cores 500, a cam 600, and a stripper plate 700 may be provided in the space between the upper mold 100 and the lower mold 200. In addition, the space between the main core 400 and the plurality of slide cores 500 may be a space in which the first molded product is formed. The main core 400 is coupled to the lower plate 300 and can be moved and fixed in position in the vertical direction, and the plurality of slide cores 500 can be retreated radially outward by driving the cam 600. there is. Additionally, when the upper mold 100 is lowered, the plurality of slide cores 500 may advance inward in the radial direction and be disposed adjacent to the main core 400. A guide block that can guide the main core 400 to slide up and down is coupled to the center of the stripper plate 700, and the main core 400 can be inserted into the guide block. In addition, an air hole is formed in the guide block to inject air between the main core 400 and the plurality of slide cores 500 to separate the primary molded product attached to the main core 400 and the slide core 500. It can be done as much as possible. Additionally, the primary molded product can be separated from the main core 400 and taken out by operating the stripper plate 700. In addition, a plurality of core pins 510 corresponding to a plurality of through holes 22 may be formed to protrude from each of the plurality of slide cores 500 to correspond to the shape of the primary molded product, and the plurality of slide cores 500 A groove 520 of a shape corresponding to the undercut 23 may be formed. Additionally, a concave space corresponding to the shape of the housing 21 may be formed in each of the plurality of slide cores 500. Additionally, the plurality of slide cores 500 may be arranged adjacent to the outside of the main core 400, and the plurality of slide cores 500 may be arranged adjacent to each other along the circumferential direction. In addition, the inner peripheral surface of each of the plurality of slide cores 500 is formed in an arc shape corresponding to the outer surface shape of the primary molded product, and the outline of the entire surface formed by the inner peripheral surface of the plurality of slide cores 500 is cylindrical. This can be.

In the first molding step, while the injection mold formed as described above is closed, the raw material of the first molded product is in liquid form and injected through the injection hole of the injection mold to form the main core 400 and the plurality of slide cores 500. It can be hardened after the raw materials are filled in between. At this time, the raw material of the first molded product injected through the injection hole may be an elastic material such as rubber, for example. Next, air is injected into the air hole of the guide block coupled to the stripper plate 700, the lower plate 300 and the main core 400 are lowered, and the upper mold 100 is lifted and opened. Next, the plurality of slide cores 500 can be opened by retracting radially outward and the stripper plate 700 can be operated to take out the first molded product. Therefore, in the first molding step, the housing 21, a plurality of through holes 22, and undercuts 23 of the first molded product 20a can be formed simultaneously.

The second molding step is a step of manufacturing the final molded product (20b) by turning over the first molded product (20a) manufactured through the first molding step so that the inner and outer sides of the first molded product (20a) are swapped. That is, the final molded product 20b that has gone through the second molding step is formed with a plurality of through holes 22 penetrating the inner and outer surfaces of the housing 21 arranged along the circumferential direction, and the housing 21 ) may have an undercut 23 protruding radially inward from the inner surfaces of the upper and lower ends. And in the first molded product 20a, a parting line PL is formed on the outer surface of the housing 21, and in the final molded product 20b, a parting line PL is formed on the inner surface of the housing 21. . Here, the parting line (PL) is caused by a fine gap where a plurality of molds constituting an injection mold meet each other, and is formed in the form of a slightly protruding line on the outer surface of the molded product.

Therefore, the method for manufacturing an electronic device exterior cover of the present invention can manufacture an accurate shape without a parting line caused by an injection mold on the outer surface of the exterior cover and without deformation of the through-hole shape and undercut shape. In addition, the exterior cover is easy to manufacture, reducing manufacturing man-hours and manufacturing costs.

Additionally, in the method of manufacturing an external cover for an electronic device of the present invention, the plurality of slide cores 500 in the injection mold may be formed as 12 or more. Here, if the number of the plurality of slide cores 500 is less than 12, the angle between the central axis direction of the through holes formed in the housing of the electronic device exterior cover and the retreating direction of the slide core 500 becomes relatively large, so that the housing The shape of the formed through hole may be deformed. That is, in the present invention, by forming the number of slide cores to 12 or more, it is possible to form through holes of an accurate shape in the housing without deforming the shape of the through holes.

In addition, it may be configured to further include a reverse-engineered injection mold cam 600, and the plurality of slide cores 500 can be retracted by driving the cam 600. Here, the plurality of slide cores 500 may be formed in two sets, with slide cores adjacent to each other in the circumferential direction forming the same group. In other words, if the slide core that serves as a standard is called the No. 1 slide core and the slide cores that rotate to one side in the circumferential direction are called the No. 12 slide cores, the odd-numbered slide cores form a group (Article 1; 501) and the even-numbered slides Cores may form another group (Article 2; 502). Thus, the plurality of slide cores may be operated so that one of the two sets of slide cores retracts radially outward and then the other set of slide cores retracts radially outward. Accordingly, it is possible to prevent the plurality of through holes 22 and undercuts 23 formed in the housing 21 of the electronic device exterior cover 20 from being torn.

The present invention is not limited to the above-described embodiments, and its scope of application is diverse, and anyone skilled in the art can understand it without departing from the gist of the invention as claimed in the claims. Of course, various modifications are possible.

10: Electronic devices
20: Electronic device exterior cover 21: Housing
22: Through hole 23: Undercut
20a: First molded product 20b: Final molded product
PL: Parting line
100: upper mold
200: lower mold
300: Hawon version
400: main core 410: air hole
500: Slide core 501: Article 1
502: Article 2 510: Core pin
520: Home
600: Cam
700: Stripper plate

Claims (11)

A mold design step of designing an injection molding mold in which the shape of the final molded product is reverse-engineered into a shape that corresponds to the shape of the object to be covered, with the inner and outer sides changed;
A first molding step of manufacturing a first molded product by injection molding an elastic raw material using the reverse engineered injection mold; and
A secondary molding step of manufacturing a final molded product by turning over the first molded product so that the inside and outside of the first molded product manufactured through the first molding step are interchanged; Including,
In the mold design stage,
The reverse engineered injection mold is formed in a shape corresponding to the shape in which a plurality of through holes penetrating the inner and outer surfaces of the housing of the primary molded product to be molded are arranged along the circumferential direction,
The reverse engineered injection molding mold includes a main core and a plurality of slide cores disposed adjacent to the outside of the main core and arranged adjacent to each other along a circumferential direction, and each of the plurality of slide cores contains a portion of the primary molded product. A core pin of a shape corresponding to the through hole is formed,
The reverse engineered injection mold is formed in a shape corresponding to the shape in which the undercut protrudes outward from the outer surface of the housing of the primary molded product to be molded,
A groove having a shape corresponding to the undercut of the first molded product is further formed in each of the plurality of slide cores,
In the first molding step, the housing of the first molded product, a plurality of through holes, and undercuts are formed simultaneously,
The reverse engineered injection molding mold further includes a cam that drives the plurality of slide cores, and the plurality of slide cores are formed in two sets by forming the same group of slide cores that are adjacent to each other in the circumferential direction,
After the primary molded product is injected and hardened in the primary molding step, one of the two sets of jaws retreats radially outwardly by driving the cam, and then the other jaw retreats radially outwardly. A plurality of slide cores A method of manufacturing an electronic device exterior cover, characterized in that it operates.
delete delete delete delete According to paragraph 1,
A method of manufacturing an electronic device exterior cover, characterized in that the plurality of slide cores are formed in 12 or more.
delete According to paragraph 1,
A method of manufacturing an electronic device exterior cover, characterized in that the primary molded product is separated from the injection mold by injecting air into the gap between the main core and the slide core before the plurality of slide cores retreat radially outward.
According to paragraph 1,
A method of manufacturing an electronic device exterior cover, wherein the first molded product has parting lines formed by a plurality of slide cores formed on the outside of the housing.
Manufactured by the electronic device exterior cover manufacturing method of any one of paragraphs 1, 6, 8, and 9,
A plurality of through holes are formed in the housing of the final molded product, an undercut is formed in the housing of the final molded product protruding radially inward from the inner surface, and a parting line formed by the injection mold is formed on the outer side of the housing of the final molded product. An electronic device exterior cover that is located on the inner surface of the housing and not on the surface. delete

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