Method of manufacturing a model car body

Abstract

The present disclosure relates to a method of manufacturing a model car body, including preparing a steel mold comprising a core plate with an inner core, a top plate and at least two side plates; attaching at least one pre-fabricated plastic block to a side of the inner core of the core plate; combining the core plate, the top plate and the at least two side plates with each other, wherein a cavity is formed among the top plate, the side plates, the inner core of the core plate and the at least one pre-fabricated plastic block; injecting melted plastic material into the cavity, wherein the melted plastic material is filled with the cavity and the at least one pre-fabricated plastic block is encased by the melted plastic material; solidifying the melted plastic so as to form the model car body, wherein the at least one pre-fabricated plastic block is integrated with the plastic model car body; separating the core plate, the top plate and the at least two side plates from each other; and releasing the model car body with the at least one pre-fabricated plastic block from the mold.

Claims

1. A method of manufacturing a model car body comprising (a) preparing a steel mold comprising a core plate having (i) an inner core, (ii) a top plate and (iii) at least two side plates; wherein the inner core comprises a side surface that tapers from a bottom portion of the inner core to a top portion of the inner core, wherein the top plate and the at least two side plates are movable from a separated position spaced from the inner core to a combined position wherein the top plate and the at least two side plates are closer to the inner core than in the separated position; wherein each of the at least two side plates comprises a first portion and a second portion with the first and second portions being configured such that, in the combined position, each of the first portions is spaced from the tapered side surface of the inner core a greater distance than each of the second portions; (b) attaching at least one pre-fabricated plastic block to the tapered side surface of the inner core such that, in the combined position, (i) the at least one pre-fabricated plastic block is disposed in a space between the first portion of each of the at least two side plates and the tapered side surface, and (ii) the top plate, the at least two side plates, the inner core and the at least one pre-fabricated plastic block form a cavity into which melted plastic material may be injected to encase the at least one pre-fabricated plastic block, wherein the at least one pre-fabricated plastic block is configured and disposed so as partially to fill the space between the first portion of each of the at least two side plates and the tapered side surface such that a thickness of the cavity is substantially uniform; (c) injecting melted plastic material into the cavity to fill the cavity and to encase the at least one pre-fabricated plastic block; (d) solidifying the injected melted plastic material to form the model car body with the at least one pre-fabricated plastic block integrated therein; (e) separating the core plate, the top plate and the at least two side plates from each other; and (f) releasing the model car body with the integrated at least one pre-fabricated plastic block from the steel mold.

2. The method according to claim 1, wherein the at least one pre-fabricated plastic block is positioned to substantially correspond to a portion of the model car where a required wall thickness is to be formed.

3. The method according to claim 1, wherein the at least one pre-fabricated plastic block is positioned to substantially correspond to a frame of a door opening of the model car body.

4. The method according to claim 1, wherein the core plate is fixed and the top plate and the at least two side plates are moveable.

5. The method according to claim 1, wherein a distance between the top plate and the inner core of the core plate, a distance between the at least two side plates and the inner core of the core plate and a distance between the at least two side plates and the at least one pre-fabricated plastic block are configured to be substantially unified when the top plate and the at least two side plates are in the combined position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic view showing a steel mold for manufacturing a plastic model car body in accordance with an embodiment of the disclosed invention.

(2) FIGS. 2A-2E are schematic views showing a manufacturing process of one embodiment of a plastic model car body in accordance with an embodiment of the disclosed invention.

(3) FIG. 3 is a schematic view showing a plastic model car body in accordance with an embodiment of the disclosed invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(4) The aforementioned illustrations and following detailed descriptions are exemplary for the purpose of further explaining the scope of the invention. Other objectives and advantages related to the invention will be illustrated in the subsequent descriptions and appended drawings.

(5) FIG. 1 shows a steel mold 1 used for manufacturing a plastic model car body. The steel mold 1 comprises a top plate 11, at least two side plates 12 and a core plate 13, wherein the core plate 13 comprises a base 131, and an inner core 132 arranged above the base 131 and the inner core 132 is tapered from its bottom to its top. The top plate 11 and the at least two side plates 12 are movable and the core plate 13 is fixed. The top plate 11 and the at least two side plates 12 could be moved to be adjacent to the core plate 13 such that they are combined with each other.

(6) FIGS. 2A-2E shows a manufacturing process of one embodiment of a plastic model car body in accordance with an embodiment of the disclosed invention. Firstly, referring to FIG. 2A, at least one pre-fabricated small plastic block 2 is attached to the inner core 132 of the core plate 13, wherein the at least one pre-fabricated small plastic block 2 is positioned to correspond to the portion of the plastic model car body where the required wall thickness will be formed, such as the frame of the door opening of the plastic model car body. As shown in FIG. 2A, two pre-fabricated small plastic blocks 2 are attached to two sides of the inner core 132 of the core plate 13, respectively.

(7) After attaching the pre-fabricated small plastic blocks 2 to the inner core 132 of the core plate 13, as shown in FIG. 2B, the top plate 11 and side plates 12 respectively move in the direction of the arrows such that the top plate 11, the side plates 12 and the core plate 13 are combined with each other and the mold 1 is closed. When the mold 1 is closed, there is a cavity 15 formed within the mold. The cavity 15 is formed as thin as possible, and the thickness of the cavity 15 is configured to be substantially constant. In other words, in the closed mold 1, the distance between the top plate 11 and the inner core 132 of the core plate 13, the distance between the side plate 12 and the inner core 132 of the core plate 13 and the distance between the side plate 12 and the pre-fabricated plastic block 2 are configured to be as short as possible and substantially unified. Generally, such distance could be ranged from 0.5 mm to 3.0 mm. That is, the thickness of the cavity 15 could be ranged from 0.5 mm to 3.0 mm.

(8) Referring to FIG. 2C, after closing the mold 1, the melted plastic 3 is injected into the cavity 15 within the mold 1. When the melted plastic 3 is filled with the cavity 15, the pre-fabricated plastic blocks 2 are encased by the melted plastic 3. After the melted plastic 3 is filled with the cavity 15, the melted plastic 3 is solidified to form a plastic model car body. Since the cavity 15 is thin and the thickness of the cavity 15 is substantially constant, the melted plastic 3 filled with the cavity 15 will have the substantially unified thin thickness and there is no shrinkage during the solidification of the melted plastic 3.

(9) Referring to FIG. 2D, after solidification of the melted plastic 3, the plastic model car body 5 is hardened into shape and the pre-fabricated plastic blocks 2 are integrated with the plastic model car body 5 and to be parts of the plastic model car body 5. Then the top plate 11 and side plates 12 respectively move in the direction of the arrows such that the top plate 11, the side plates 12 and the core plate 13 are separated from each other and the mold 1 is opened.

(10) Since the plastic blocks 2 are integrated with the plastic model car body 5 and to be parts of the plastic model car body 3, the portions of the model car body 5, which are integrated with the plastic blocks 2, will have a greater wall thickness than other portions of the plastic model car body 5, which are not integrated with the plastic blocks 2. That is, the plastic blocks 2 are used to create additional wall thicknesses of the plastic model car body 5 and thus the plastic model car body 5 can have different wall thicknesses at various portions.

(11) Moreover, the plastic blocks 5 integrated with the inner surface of the plastic model car body 5 will also form the “draft angles” at the interior of the plastic model car body such that the plastic model car body 5 could be easily released from the inner core 132 of the core plate 13.

(12) Referring to FIG. 2E, after opening the mold 1, the plastic model car body 5 is released from the inner core 132 of the core plate 13.

(13) FIG. 3 shows a plastic model car body 5 in accordance with an embodiment of the disclosed invention. As shown in FIG. 3, the plastic blocks 2 are integrated with the inner surface of the plastic model car body 5 and they are positioned at the frame of the door opening of the plastic model car 5. Generally, the wall thickness of the plastic model car body 5 is reduced as much as possible. The wall thickness of the plastic model car body 5 could be ranged from 0.5 mm to 3.0 mm. The plastic blocks 5 is used to create the additional wall thicknesses on the inner surface of the plastic model car body 3 such that the plastic model car body 3 has greater wall thicknesses at the portions integrated with the plastic blocks 2. Referring to FIG. 3, the plastic model car body 3 has greater wall thicknesses at the frame of the door opening.

(14) In addition, if the model car body 5 has any specific area which requires excessive wall thickness, the plastic block 2 could be positioned at such area, such as inner side of front and rear bumpers, or underneath the roof panel.

(15) As abovementioned, the increased wall thickness of the plastic model car body 5 is created by insertion of the pre-fabricated plastic block 2 rather than the solidification of the melted plastic 3. The portion of the plastic model car body 5 with the greater wall thickness will not be shrunk when the melted plastic 3 is solidified. Thus, the whole outer surface of the plastic model car body 5 could be kept smooth after the plastic model car body 5 hardened into shape.

(16) However, the above embodiments merely describe the principle and effects of the present disclosure instead of being used to limit the present disclosure. Therefore, persons skilled in the art can make modifications and variations to the above embodiments without departing from the spirit of the present disclosure. The scope of the present disclosure should be defined by the appended claims.