Containers and methods for manufacturing containers
By using whitened polyethylene terephthalate resin for the bearing portions and shafts, the container's hinge functionality is maintained, and recyclability is enhanced by preventing size changes, addressing the deterioration issues in resin containers.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- YOSHINO KOGYOSHO CO LTD
- Filing Date
- 2025-04-23
- Publication Date
- 2026-07-07
Smart Images
Figure 2026113370000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a container and a method for manufacturing the container.
Background Art
[0002] Conventionally, a container is known that includes a resin container body and a lid body, and a hinge portion that rotatably connects the lid body to the container body, and the hinge portion is composed of a resin bearing portion and a resin shaft that fits into the bearing portion (see, for example, Patent Document 1). In the structure of Patent Document 1, by forming many of the constituent parts of the container, such as the bearing portion and the shaft, with resin, the separation of the constituent parts can be facilitated and the recyclability of the container can be improved.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] However, when the bearing portion is made of resin as in Patent Document 1, for example, the size of the bearing portion may change due to changes over time, and the function of the hinge portion may deteriorate. Therefore, it is desirable to suppress changes in the size of the bearing portion and maintain the function of the hinge portion well. Also, for example, the size of the shaft may change due to changes over time. Therefore, it is desirable to suppress changes in the size of the shaft and maintain the function of the hinge portion well.
[0005] In view of such points, an object of the present invention is to suppress changes in the sizes of a resin bearing portion and a shaft in a container and a method for manufacturing the container, and to maintain the function of the hinge portion well.
Means for Solving the Problems
[0006] The container comprises a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, wherein the bearing portion is made of whitened polyethylene terephthalate resin.
[0007] A method for manufacturing a container comprises a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, wherein the bearing portion is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold, and the bearing portion is formed by changing the cooling conditions of the mold with respect to the portion surrounding the bearing portion to whiten the polyethylene terephthalate resin.
[0008] Furthermore, the method for manufacturing a container comprises a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, wherein the bearing portion is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold, and the bearing portion is formed by whitening the polyethylene terephthalate resin by heating after the resin molding.
[0009] The container comprises a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, wherein the shaft is made of whitened polyethylene terephthalate resin.
[0010] A method for manufacturing a container comprises a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, wherein the shaft is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold, and the shaft is formed by changing the cooling conditions of the mold with respect to the portion around the shaft to whiten the polyethylene terephthalate resin.
[0011] Furthermore, the method for manufacturing a container comprises a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, wherein the shaft is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold, and the shaft is formed by whitening the polyethylene terephthalate resin by heating after the resin molding. [Effects of the Invention]
[0012] According to the present invention, in a container and a method for manufacturing a container, changes in the size of the resin bearing and shaft can be suppressed, and the function of the hinge can be maintained well. [Brief explanation of the drawing]
[0013] [Figure 1] This is a perspective view showing a compact container. [Figure 2] This is a perspective view of the disassembled container body. [Figure 3] This is a perspective view of the lid from above when the lid is closed. [Figure 4] This is a cross-sectional view of the lid-side shaft support portion, viewed in the axial direction of the shaft. [Figure 5] This is a perspective view showing a compact container according to a second embodiment. [Figure 6] This is a disassembled perspective view of the compact container. [Figure 7]It is an exploded perspective view of the container body in the third embodiment. [Figure 8] It is a perspective view of the lid body as seen from above in the state where the lid body is closed. [Figure 9] It is an exploded perspective view of the compact container in the fourth embodiment.
Embodiments for Carrying out the Invention
[0014] Hereinafter, an embodiment of a container and a method for manufacturing the container according to the present invention will be described with reference to the drawings. In the present specification and the like, "upper" and "lower" refer to the vertical direction in the state where the container body 11 is placed on a horizontal plane. Also, "rear" is the side where the hinge portion 13 is provided, and "front" is the opposite side of "rear". Further, "left" and "right" refer to the left - right direction when viewed from the front to the rear.
[0015] [First Embodiment] FIG. 1 is a perspective view showing a compact container 10 (container). The compact container 10 is a container for storing a solid content such as a pressed powder obtained by solidifying a powder cosmetic and an applicator such as a puff. The compact container 10 includes a container body 11 for storing the content and a lid body 12 that covers the container body 11 in an openable and closable manner. Further, the compact container 10 is provided with a hinge portion 13 that connects the lid body 12 to the container body 11 in a rotatable manner. The lid body 12 can be opened and closed by the hinge portion 13. In FIG. 1, a state where the lid body 12 is opened approximately 90° is illustrated.
[0016] FIG. 2 is an exploded perspective view of the container body 11. FIG. 3 is a perspective view of the lid body 12 as seen from above in the state where the lid body 12 is closed. In FIGS. 2 and 3, a shaft 15 that forms a part of the hinge portion 13 is also illustrated. The hinge portion 13 includes a shaft 15 that extends horizontally in the left - right direction, a main - body - side bearing portion 16 provided on the container body 11 into which the shaft 15 is fitted, and a lid - side bearing portion 17 provided on the lid body 12 into which the shaft 15 is fitted.
[0017] Referring to FIGS. 1 and 2, the container body 11 includes a bottom cover 20 that constitutes the outer shell of the container body 11, and a container middle frame 21 housed in the bottom cover 20. The bottom cover 20 is formed in a substantially rectangular tray shape in plan view. The bottom cover 20 includes a substantially rectangular bottom surface portion 22 and a bottom cover peripheral wall portion 23 erected from the periphery of the bottom surface portion 22. The bottom cover peripheral wall portion 23 includes a front wall portion 24 erected from the front edge of the bottom surface portion 22, a rear wall portion 25 erected from the rear edge of the bottom surface portion 22, and a pair of left and right side wall portions 26 erected from the left and right edges of the bottom surface portion 22, respectively.
[0018] At the left and right central portions at the rear end of the bottom cover 20, a bottom cover recess 27 is formed by cutting out the rear wall portion 25 and the bottom surface portion 22 forward. In plan view, the left and right central portions at the rear end of the bottom cover 20 are recessed forward in a substantially rectangular shape by the bottom cover recess 27.
[0019] The container middle frame 21 includes a middle frame bottom wall portion 30 arranged to be placed on the bottom surface portion 22 of the bottom cover 20, a middle frame peripheral wall portion 31 erected from the periphery of the middle frame bottom wall portion 30, a flange portion 32 extending outward of the middle frame peripheral wall portion 31 in plan view from the upper edge of the middle frame peripheral wall portion 31, and a container side shaft support portion 33 extending rearward from the rear surface of the rear portion of the middle frame peripheral wall portion 31.
[0020] Inside the container middle frame 21, partition walls 30a are provided at the left and right central portions of the middle frame bottom wall portion 30, so that left and right storage portions 21a and 21b are partitioned. In the left storage portion 21a, a middle dish (not shown) for storing the contents is stored. In the right storage portion 21b, an application tool (not shown) such as a puff is stored. The container middle frame 21 is attached to the bottom cover 20 by fitting the middle frame peripheral wall portion 31 inside the bottom cover peripheral wall portion 23 of the bottom cover 20. Also, the flange portion 32 of the container middle frame 21 abuts on the upper edge of the bottom cover peripheral wall portion 23 of the bottom cover 20 from above.
[0021] The inner frame peripheral wall portion 31 includes an inner frame rear wall portion 31a that faces the rear wall portion 25 of the bottom cover 20 from the front. The flange portion 32 also includes a rear flange portion 32a that extends rearward from the upper edge of the inner frame rear wall portion 31a. At the left and right center of the rear flange portion 32a, flange-side recesses 32b are provided that are recessed forward along the bottom cover recess 27 of the bottom cover 20.
[0022] The container-side shaft support portion 33 protrudes rearward from the rear surface of the rear wall portion 31a of the inner frame, below the rear flange portion 32a. The upper surface of the container-side shaft support portion 33 is connected to the lower surface of the rear flange portion 32a. The container-side shaft support portions 33 are provided in pairs, one on the left and one on the right, positioned to the left and right of the flange-side recess 32b. A space K is provided between the left and right container-side shaft support portions 33, separating the pair of container-side shaft support portions 33 from each other in the left-right direction. The space K is exposed upward from the flange-side recess 32b. In Figure 1, the left container-side shaft support portion 33 is visible from the flange-side recess 32b.
[0023] The main body side bearing portion 16 is provided on the left and right container side shaft support portions 33, respectively. The main body side bearing portion 16 is a hole that penetrates the container side shaft support portion 33 in the axial direction (left-right direction) of the shaft 15. A pair of shafts 15 are provided, one on the left and one on the right, and they are fitted into the left and right main body side bearing portions 16, respectively.
[0024] Referring to Figures 1 and 3, the lid 12 comprises a lid body 40 that is connected to the shaft 15 and rotates, an inner frame 41 (Figure 1) attached to the lid body 40, and a plate-shaped mirror 42 (Figure 1) held by the inner frame 41. The lid body 40 comprises a top plate portion 44 that covers the container body 11 from above when closed, a peripheral wall portion 45 that extends downward from the peripheral edge of the top plate portion 44, and a lid-side shaft support portion 46 that extends downward from the rear end of the top plate portion 44.
[0025] The top plate 44 is a roughly rectangular plate that conforms to the outer shape of the container body 11 when viewed from above. The peripheral wall portion 45 is roughly rectangular in shape when viewed from above. The middle frame 41 is a frame-shaped member that fits onto the inner surface of the peripheral wall portion 45. At the rear of the middle frame 41, the left and right central portions are provided with engaging pieces 41a (Figure 1) that extend downward. The mirror 42 is attached to the lid 12 by being sandwiched between the upper surface of the inner frame 41 and the lower surface of the top plate 44 when the lid 12 is closed.
[0026] The lid-side shaft support portion 46 is a wall-like portion provided in the left and right central parts of the rear end of the top plate portion 44, and extends in the left-right direction along the shaft 15. A notch 46a is provided in the left and right central parts of the lid-side shaft support portion 46, which is cut out from the bottom surface upward of the lid-side shaft support portion 46. The inner frame 41 is supported by the lid 12 by the engagement of an engaging piece 41a (Figure 1) with the front surface of the lid-side shaft support portion 46. As shown in Figure 1, when the lid 12 is attached to the container body 11, the lid-side shaft support portion 46 is housed in the space K provided by the container body 11.
[0027] The lid-side bearing portion 17 is provided on the lid-side shaft support portion 46. The lid-side bearing portion 17 is a pair of left and right holes that extend from both the left and right sides of the lid-side shaft support portion 46 in the axial direction (left-right direction) of the shaft 15, and does not penetrate the lid-side shaft support portion 46. The left shaft 15 is fitted into the left lid-side bearing portion 17 (not shown), and the right shaft 15 is fitted into the right lid-side bearing portion 17.
[0028] Here, we will explain an example of the procedure for attaching the lid 12 to the container body 11. First, the lid 12 is set on the container inner frame 21 in the state shown in Figure 2, such that the lid-side shaft support portion 46 (Figure 3) is housed in space K. In this state, the position of the lid 12 is adjusted so that the main body-side bearing portion 16 and the lid-side bearing portion 17 are arranged almost coaxially.
[0029] Next, the shaft 15 is inserted into each body-side bearing portion 16 from the left and right outer sides, and then the shaft 15 is pushed further in to insert it into the lid-side bearing portion 17. At this point, the shaft 15 is inserted until it abuts against the bottom of the lid-side bearing portion 17. In this state, each shaft 15 is fitted into both the body-side bearing portion 16 and the lid-side bearing portion 17. In detail, the left and right outer portion of the shaft 15 is the body-side fitting shaft portion 15a that fits into the body-side bearing portion 16, and the left and right inner portion of the shaft 15 is the lid-side fitting shaft portion 15b that fits into the lid-side bearing portion 17. In this way, the lid 12 is connected to the container inner frame 21 via the shaft 15. Subsequently, by attaching the container inner frame 21 to the bottom lid 20, the lid 12 is attached to the container body 11. The lid 12 is opened and closed relative to the container body 11 by rotating around the axis 15.
[0030] Next, the configuration of the hinge portion 13 will be described in detail. The bottom lid 20, container inner frame 21, lid body 40, and shaft 15 that make up the container body 11 are made of polyethylene terephthalate resin. The container-side shaft support portion 33 is a part integrally formed with the container inner frame 21, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin. Furthermore, the lid-side shaft support portion 46 is a part integrally formed with the lid body 40, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin.
[0031] Figure 4 is a cross-sectional view of the lid-side shaft support portion 46 as seen in the axial direction of the shaft 15. The lid-side bearing portion 17 is a part of the lid-side shaft support portion 46 into which the shaft 15 is fitted, and is whitened in an annular shape when viewed in the axial direction. It is made of whitened polyethylene terephthalate resin.
[0032] In detail, the lid-side bearing portion 17 comprises a circular hole 17a through which the shaft 15 is inserted, and a cylindrical whitened portion 17b that partitions the hole 17a. The whitened area 17b is the part where the polyethylene terephthalate resin has crystallized and turned white. In the lid-side shaft support portion 46, the portion other than the whitened portion 17b is made of amorphous polyethylene terephthalate resin. Furthermore, in the lid body 40, the portion other than the whitened portion 17b is made of amorphous polyethylene terephthalate resin.
[0033] Referring to Figure 2, the main body side bearing portion 16 is the part of the container side shaft support portion 33 into which the shaft 15 is fitted, and which has been whitened in an annular shape in an axial view, and is made of whitened polyethylene terephthalate resin.
[0034] In detail, the main body bearing portion 16 comprises a circular hole 16a through which the shaft 15 is inserted, and a cylindrical whitened portion 16b that partitions the hole 16a. The whitened area 16b is the part where the polyethylene terephthalate resin has crystallized and turned white. In the container-side shaft support portion 33, the portion other than the whitened portion 16b is made of amorphous polyethylene terephthalate resin. Furthermore, in the container inner frame 21, the portion other than the whitened portion 16b is made of amorphous polyethylene terephthalate resin.
[0035] The shaft 15 is made of amorphous polyethylene terephthalate resin. The main body side fitting shaft portion 15a of the shaft 15 is press-fitted and fixed to the inner circumferential surface of the whitened portion 16b of the main body side bearing portion 16. More specifically, the main body side fitting shaft portion 15a is press-fitted to the main body side bearing portion 16 with sufficient force to prevent rotation. Thus, the main body side bearing portion 16 can also be said to be a shaft fixing portion, as it is the part that fixes the shaft 15 so that it does not rotate.
[0036] Furthermore, the lid-side fitting shaft portion 15b of the shaft 15 is press-fitted into the inner circumferential surface of the whitened portion 17b of the lid-side bearing portion 17. Here, the lid-side fitting shaft portion 15b is press-fitted with sufficient force to allow the lid-side bearing portion 17, which is fitted into the lid-side fitting shaft portion 15b, to rotate relative to the lid-side fitting shaft portion 15b. In detail, the lid-side fitting shaft portion 15b is press-fitted into the whitened portion 17b with sufficient force to provide a free-stop function that allows the lid 12 to stop at any rotational position. The free-stop function allows the lid 12 to be rotated to any desired position, and even when the lid 12 is not being supported by a hand or the like, the frictional force between the lid-side fitting shaft portion 15b and the whitened portion 17b keeps the lid 12 stopped at the desired rotational position.
[0037] In other words, the lid 12 is rotatably mounted on a shaft 15 fixed to the main body bearing portion 16, in a state that allows it to exhibit a free-stop function. Here, the whitened portions 16b and 17b are parts where the polyethylene terephthalate resin has crystallized, and since the changes over time are suppressed compared to amorphous polyethylene terephthalate resin, the increase in the inner diameter of the whitened portions 16b and 17b due to changes over time is suppressed. This allows the press-fit state between the whitened portion 17b of the lid-side bearing portion 17 and the lid-side fitting shaft portion 15b to be maintained in good condition, and the free-stop function can be performed effectively. Furthermore, the press-fit state between the whitened portion 16b of the main body bearing portion 16 and the main body fitting shaft portion 15a can be maintained in good condition, allowing the free-stop function to be performed effectively.
[0038] Furthermore, the inventors of the present invention measured the density of both whitened polyethylene terephthalate resin and non-whitened amorphous polyethylene terephthalate resin. As a result, the density of the whitened polyethylene terephthalate resin was 1.375 to 1.38 (g / cm³). 3 ) was. Furthermore, the density of amorphous polyethylene terephthalate resin is 1.33-1.34 (g / cm³). 3 ) was. Thus, the fact that the density of the whitened polyethylene terephthalate resin is higher than that of the amorphous polyethylene terephthalate resin is considered to be one of the factors that suppresses the aging process of the whitened polyethylene terephthalate resin.
[0039] Furthermore, the inventors measured the torque required to rotate the shaft 15 relative to the bearing portion when the bearing portion of the shaft 15 was whitened and when the bearing portion of the shaft 15 was left amorphous without whitening. To confirm the effect of changes over time, the inventors conducted an accelerated test in which the shaft 15 and the bearing portion were subjected to a 50°C environment for one week, and measured the torque after this test. As a result, the torque when the bearing portion was whitened was 10.1 (N·cm), while the torque when the bearing portion was amorphous was 5.5 (N·cm), indicating that the torque was greater when the bearing portion was whitened. This is thought to be because when the bearing portion was whitened, the expansion of the inner diameter of the bearing portion due to the aging of the polyethylene terephthalate resin was suppressed, and the press-fit state between the bearing portion and the shaft 15 was maintained in a good condition.
[0040] The lid body 40, which has a whitened portion 17b, is formed by injecting polyethylene terephthalate resin into the cavity of a mold and cooling the polyethylene terephthalate resin within the cavity. The lid-side bearing portion 17 is formed integrally with the lid body 40 during resin molding using a mold. Specifically, for example, polyethylene terephthalate resin is heated to 280°C to 300°C and injected into the cavity, and then cooled. At this time, the lid-side bearing portion 17 is formed by changing the cooling conditions for the parts surrounding the lid-side bearing portion 17. For example, when cooling the lid body 40 in the mold, while other parts are cooled slowly, the temperature of only the lid-side bearing portion 17 is adjusted so that it is maintained at a temperature of 80°C to 100°C for a predetermined time, thereby forming the whitened portion 17b.
[0041] The container inner frame 21, which includes the whitened portion 16b, is formed by injecting polyethylene terephthalate resin into the cavity of a mold and cooling the polyethylene terephthalate resin within the cavity. The main body bearing portion 16 is formed integrally with the container inner frame 21 during resin molding using a mold. Specifically, for example, polyethylene terephthalate resin is heated to 280°C to 300°C and injected into the cavity, and then cooled. At this time, the main body bearing portion 16 is formed by changing the cooling conditions for the parts surrounding the main body bearing portion 16. For example, when cooling the container inner frame 21 in the mold, while other parts are cooled slowly, the temperature of the main body bearing portion 16 is adjusted so that it is maintained at a temperature of 80°C to 100°C for a predetermined time, thereby forming the whitened portion 16b.
[0042] Furthermore, the lid-side bearing portion 17 and the body-side bearing portion 16 can also be formed by a method other than changing the cooling conditions within the mold. For example, after the lid body 40 and the container inner frame 21 are molded using resin molding with a mold, heaters can be inserted into the lid-side bearing portion 17 and the body-side bearing portion 16, and the whitened portions 16b and 17b can be formed by heating the lid-side bearing portion 17 and the body-side bearing portion 16 from the inside with the heaters.
[0043] As described above, according to the first embodiment to which the present invention is applied, the compact container 10 comprises a container body 11, a lid body 40 that covers the container body 11 in an openable and closable manner, and a hinge portion 13 that rotatably connects the lid body 40 to the container body 11 by a body-side bearing portion 16 and a lid-side bearing portion 17, and a shaft 15 that fits into the bearing portion. The body-side bearing portion 16 and the lid-side bearing portion 17 are made of whitened polyethylene terephthalate resin. With this configuration, the main body bearing portion 16 and the lid bearing portion 17 are made of whitened polyethylene terephthalate resin, thus suppressing changes in the size of the main body bearing portion 16 and the lid bearing portion 17. As a result, the fit between the main body bearing portion 16 and the lid bearing portion 17 and the shaft 15 can be maintained in good condition, and the function of the hinge portion 13 can be maintained in good condition.
[0044] Furthermore, the main body bearing portion 16 is integrally provided with the container body 11, which is made of polyethylene terephthalate resin, and the fitting portion into which the shaft 15 fits is the annular whitened portion when viewed in the axial direction. Similarly, the lid bearing portion 17 is integrally provided with the lid body 40, which is made of polyethylene terephthalate resin, and the fitting portion into which the shaft 15 fits is the annular whitened portion when viewed in the axial direction. With this configuration, the fitting portions of the container body 11 and lid body 40, which are made of polyethylene terephthalate resin, can be whitened in an annular shape to form the body-side bearing portion 16 and the lid-side bearing portion 17. This makes it easy to form the body-side bearing portion 16 and the lid-side bearing portion 17, which can suppress changes in size. Furthermore, since there is no need to whiten the parts of the container body 11 and lid body 40 other than the body-side bearing portion 16 and the lid-side bearing portion 17, the body-side bearing portion 16 and the lid-side bearing portion 17 can be easily formed. Furthermore, it is sufficient if at least one of the main body side bearing portion 16 and the lid side bearing portion 17 is made of whitened polyethylene terephthalate resin.
[0045] Furthermore, the container body 11 has a body-side bearing portion 16 into which the shaft 15 is fitted, and the lid body 40 has a lid-side bearing portion 17 into which the shaft 15 is fitted. At least one of the body-side bearing portion 16 and the lid-side bearing portion 17 is made of whitened polyethylene terephthalate resin as the bearing portion. With this configuration, by using whitened polyethylene terephthalate resin for at least one of the main body side bearing portion 16 and the lid side bearing portion 17, the fit between the bearing portion and the shaft 15 can be maintained well. Therefore, the function of the hinge portion 13 can be maintained well.
[0046] Furthermore, the shaft 15 is made of polyethylene terephthalate resin. With this configuration, the main body bearing portion 16 and the lid bearing portion 17 are made of the same polyethylene terephthalate resin as the shaft 15, even when they have whitened and their size changes can be suppressed. Therefore, when disposing of the shaft 15, the main body bearing portion 16, and the lid bearing portion 17, separation is not required, resulting in good recyclability.
[0047] Furthermore, the container body 11, the lid body 40, the body-side bearing portion 16, and the lid-side bearing portion 17 are made of polyethylene terephthalate resin. This configuration eliminates the need to separate the container body 11, lid body 40, body-side bearing part 16, lid-side bearing part 17, and shaft 15 during disposal, resulting in good recyclability.
[0048] The manufacturing method for the compact container 10 is a method for manufacturing a container comprising a container body 11, a lid body 40 that covers the container body 11 in an openable and closable manner, and a hinge portion 13 that rotatably connects the lid body 40 to the container body 11 by a body-side bearing portion 16, a lid-side bearing portion 17, and a shaft 15 that fits into these bearing portions. The body-side bearing portion 16 is formed integrally with the container body 11 by resin molding polyethylene terephthalate resin in a mold, and the lid-side bearing portion 17 is formed integrally with the lid body 40 by resin molding polyethylene terephthalate resin in a mold. The body-side bearing portion 16 and the lid-side bearing portion 17 are formed by changing the cooling conditions of the mold for the parts surrounding the body-side bearing portion 16 and the lid-side bearing portion 17 to whiten the polyethylene terephthalate resin. According to this manufacturing method, the whitened main body side bearing portion 16 and the lid side bearing portion 17 are formed by changing the cooling conditions of the mold for the parts surrounding the main body side bearing portion 16 and the lid side bearing portion 17, thus making it easy to form the whitened bearing portion.
[0049] Furthermore, the manufacturing method for the compact container 10 is a method for manufacturing a container comprising a container body 11, a lid body 40 that covers the container body 11 in an openable and closable manner, and a hinge portion 13 that rotatably connects the lid body 40 to the container body 11 by a body-side bearing portion 16, a lid-side bearing portion 17, and a shaft 15 that fits into these bearing portions. The body-side bearing portion 16 is formed integrally with the container body 11 by resin molding polyethylene terephthalate resin in a mold, and the lid-side bearing portion 17 is formed integrally with the lid body 40 by resin molding polyethylene terephthalate resin in a mold. The body-side bearing portion 16 and the lid-side bearing portion 17 are formed by whitening the polyethylene terephthalate resin by heating after resin molding. According to this manufacturing method, after integrally molding the main body bearing portion 16 and the lid bearing portion 17 with the container body 11 and lid body 40 using a mold, the molded main body bearing portion 16 and lid bearing portion 17 are heated to form bearing portions in which polyethylene terephthalate resin has turned white. Therefore, the main body bearing portion 16 and the lid bearing portion 17 can be easily formed.
[0050] [Second Embodiment] A second embodiment to which the present invention is applied will be described below with reference to Figures 5 and 6. In this second embodiment, parts configured in the same way as in the first embodiment will be denoted by the same reference numerals and their descriptions will be omitted. The second embodiment differs from the first embodiment in that the bearing portion is provided only on the container body 211 side.
[0051] Figure 5 is a perspective view showing the compact container 210 of the second embodiment. Figure 6 is an exploded perspective view of the compact container 210. The compact container 210 comprises a container body 211 for storing contents and a lid body 240 that covers the container body 211 in an openable and closable manner. Furthermore, the compact container 210 is provided with a hinge portion 213 that rotatably connects the lid body 240 to the container body 211.
[0052] The hinge portion 213 comprises a shaft 215 provided on the lid body 240 and extending horizontally in the left-right direction, and a body-side bearing portion 216 provided on the container body 211 into which the shaft 215 is fitted.
[0053] The container body 211 comprises a circular bottom wall 222 in plan view, a main body peripheral wall portion 223 erected from the periphery of the bottom wall 222, and a rear recess 224 formed by cutting out the rear end of the main body peripheral wall portion 223 toward the front in plan view. The rear recess 224 is provided, and a container-side shaft support portion 233 is formed at the rear of the main body peripheral wall portion 223, projecting rearward from the rear recess 224. A pair of container-side shaft support portions 233 are provided on both the left and right outer sides relative to the rear recess 224.
[0054] The main body side bearing portion 216 is provided on the left and right container side shaft support portions 233, respectively. The main body side bearing portion 216 is a hole that penetrates the container side shaft support portion 233 in the axial direction (left-right direction) of the shaft 215. The left and right inner ends of the main body side bearing portion 216 open into the rear side recess 224.
[0055] Guide grooves 224b are provided on both the left and right side walls 224a of the rear recess 224, extending from the upper end of the side wall 224a to the inner end of the main body side bearing portion 216. The upper end of the guide groove 224b is open upward. Furthermore, the lower end of the guide groove 224b is provided with a sloping portion 224c that slopes downward so as it approaches the inner end of the main body side bearing portion 216.
[0056] The lid body 240 comprises a top plate portion 244 that covers the container body 211 from above when closed, a peripheral wall portion 245 that extends downward from the peripheral edge of the top plate portion 244, and a lid-side shaft support portion 246 that extends downward from the rear end of the top plate portion 244.
[0057] The top plate portion 244 is a circular plate that conforms to the outer shape of the container body 211 when viewed from above. The lid-side shaft support portion 246 is a wall-like portion provided in the center of the left and right rear ends of the top plate portion 244. As shown in Figure 5, when the lid body 240 is attached to the container body 211, the lid-side shaft support portion 246 is housed in the space within the rear recess 224.
[0058] The shaft 215 is a projection that protrudes outward in the left-right direction from both the left and right sides of the lid-side shaft support portion 246. The shaft 215 is integrally formed with the lid body 240 when the lid body 240 is resin-molded in a mold. As shown in Figure 6, when the lid body 240 is in the closed position, the lower surface of the tip of the shaft 215 is provided with a shaft-side inclined portion 215a that is inclined to follow the inclined portion 224c.
[0059] Here, we will explain an example of the procedure for attaching the lid body 240 to the container body 211. First, the lid body 240 is set onto the container body 211 in the state shown in Figure 6, such that the lid-side shaft support portion 246 is housed in the rear recess 224. At this time, by moving the lid body 240 downward with the left and right shafts 215 inserted into the guide grooves 224b, the shafts 215 can be guided toward the body-side shaft bearing portion 216. Then, when the shaft-side inclined portion 215a of the shaft 215 moves downward over the inclined portion 224c, the shaft 215 fits into the body-side shaft bearing portion 216. The lid body 240 is opened and closed relative to the container body 211 by rotating around the shaft 215.
[0060] Next, the configuration of the hinge portion 213 will be described in detail. The container body 211 and the lid body 240 are made of polyethylene terephthalate resin. The container-side shaft support portion 233 is a part integrally formed with the container body 211, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin. Furthermore, the shaft 215 is a part integrally formed with the lid body 240, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin.
[0061] The main body side bearing portion 216 is the part of the container side shaft support portion 233 into which the shaft 215 is fitted, and which has been whitened in an annular shape when viewed in the axial direction. It is made of whitened polyethylene terephthalate resin. In detail, the main body side bearing portion 216 comprises a circular hole 216a through which the shaft 215 is inserted, and a cylindrical whitened portion 216b that partitions the hole 216a. In the container body 211, the parts other than the whitened portion 216b are made of amorphous polyethylene terephthalate resin. Furthermore, in the compact container 210, the parts other than the whitened portion 216b, including the shaft 215, are made of amorphous polyethylene terephthalate resin.
[0062] The whitened portion 216b can be formed in the same manner as in the first embodiment by changing the cooling conditions of the body-side bearing portion 216 within the mold used to form the container body 211. Alternatively, the whitened portion 216b may be formed by heating the body-side bearing portion 216 with a heater after the container body 211 has been formed in the mold.
[0063] As described above, according to the second embodiment to which the present invention is applied, the shaft 215 is integrally formed with the lid body 240, and the body-side bearing portion 216 is integrally formed with the container body 211. In this configuration, the shaft 215 is integrally formed with the lid body 240, and the shaft 215 does not rotate relative to the lid body 240, which is integral with the shaft 215. Therefore, by whitening the body-side bearing portion 216, which is integrally formed with the container body 211, the fitting state between the body-side bearing portion 216 and the shaft 215 can be maintained well, and the function of the hinge portion 213 can be maintained well with a simple structure. The shaft may be integrally formed on either the container body 211 or the lid body 240, and the bearing portion may be integrally formed on the other of the container body 211 or the lid body 240. For example, the bearing portion may be formed on the lid body 240 and the shaft on the container body 211.
[0064] Although one embodiment of the present invention has been described above, the present invention is not limited to such specific embodiments, and unless otherwise specifically limited in the above description, various modifications and changes are possible within the scope of the spirit of the present invention as described in the claims. For example, the configurations of the embodiments described above can be added or deleted as appropriate, and the configuration of one embodiment can be provided in other embodiments. Furthermore, the effects in the embodiments described above are merely illustrative of the effects that may arise from the present invention, and do not mean that the effects of the present invention are limited to the effects described above. In the first embodiment described above, the main body side fitting shaft portion 15a of the shaft 15 is fixed to the main body side bearing portion 16, and the lid side bearing portion 17 is rotatable relative to the lid side fitting shaft portion 15b. However, the present invention is not limited to this. For example, the lid side fitting shaft portion 15b of the shaft 15 may be fixed to the lid side bearing portion 17, and the main body side fitting shaft portion 15a may be rotatable relative to the main body side bearing portion 16. Furthermore, the main body side fitting shaft portion 15a of the shaft 15 may be rotatable relative to the main body side bearing portion 16, and the lid side bearing portion 17 may be rotatable relative to the lid side fitting shaft portion 15b.
[0065] Furthermore, in the above embodiment, the bearing portion such as the lid-side bearing portion 17 was described as a portion in which the fitting portion into which the shaft 15 is fitted is whitened in an annular shape when viewed in the axial direction, but the present invention is not limited to this. A wider area than the cylindrical whitened portion 17b may be whitened, for example, the entire lid-side shaft support portion 46 (Figure 4) may be whitened. Furthermore, since the shaft 15 is solid and less prone to shrinkage than the bearing portion, it does not need to be whitened, but it is also possible to configure it so that the shaft 15 is whitened in addition to the bearing portion.
[0066] [Third Embodiment] A third embodiment to which the present invention is applied will be described below with reference to Figures 7 and 8. In this third embodiment, parts configured in the same way as in the first embodiment will be denoted by the same reference numerals and their description will be omitted. In the first embodiment described above, the bearing portion (the bearing portion 16 on the main body side and the bearing portion 17 on the lid side) was whitened, but this third embodiment differs from the first embodiment in that the shaft 315 is whitened instead of the bearing portion.
[0067] Figure 7 is an exploded perspective view of the container body 311 in the third embodiment. Figure 8 is a perspective view of the lid 312 from above when the lid 312 is closed. In Figures 7 and 8, the shaft 315 which constitutes part of the hinge portion 313 is also shown.
[0068] The container body 311 is equipped with a body-side bearing portion 316 in place of the body-side bearing portion 16 (Figure 2) of the first embodiment. Since the container body 311 is the same as the container body 11 of the first embodiment except for the body-side bearing portion 316, the same reference numerals are used for parts that are configured in the same way and their descriptions are omitted.
[0069] Furthermore, the lid 312 is equipped with a lid-side bearing portion 317 instead of the lid-side bearing portion 17 (Figure 3) of the first embodiment described above. Since the structure of the lid 312 is the same as that of the lid 12 of the first embodiment described above, the same reference numerals are used for parts that are configured in the same way and their description is omitted.
[0070] The hinge portion 313, which rotatably connects the lid 312 to the container body 311, comprises a shaft 315 extending horizontally in the left-right direction, a bearing portion 316 on the body side, and a bearing portion 317 on the lid side.
[0071] Referring to Figure 7, the main body side bearing portion 316 is provided in the left and right container side shaft support portions 33, respectively. The main body side bearing portion 316 is a hole that penetrates the container side shaft support portion 33 in the axial direction (left-right direction) of the shaft 315. A pair of shafts 315 are provided, one on the left and one on the right, and they fit into the left and right main body side bearing portions 316, respectively.
[0072] Referring to Figure 8, the lid-side bearing portion 317 is provided on the lid-side shaft support portion 46. The lid-side bearing portion 317 is a pair of left and right holes that extend from both the left and right sides of the lid-side shaft support portion 46 in the axial direction (left-right direction) of the shaft 15, and does not penetrate the lid-side shaft support portion 46. The left shaft 315 is fitted into the left lid-side bearing portion 317 (not shown), and the right shaft 315 is fitted into the right lid-side bearing portion 317.
[0073] Here, we will explain an example of the procedure for attaching the lid 312 to the container body 311. First, the lid 312 is set on the container inner frame 21 in the state shown in Figure 7, such that the lid-side shaft support portion 46 (Figure 8) is housed in space K. In this state, the position of the lid 312 is adjusted so that the main body-side bearing portion 316 and the lid-side bearing portion 317 are arranged almost coaxially.
[0074] Next, the shaft 315 is inserted into each body-side bearing portion 316 from the left and right outer sides, and then the shaft 315 is pushed in further to insert it into the lid-side bearing portion 317 as well. At this point, the shaft 315 is inserted until it abuts against the bottom of the lid-side bearing portion 317. In this state, each shaft 315 is fitted into both the body-side bearing portion 316 and the lid-side bearing portion 317. In detail, the left and right outer portion of the shaft 315 is the body-side fitting shaft portion 315a that fits into the body-side bearing portion 316, and the left and right inner portion of the shaft 315 is the lid-side fitting shaft portion 315b that fits into the lid-side bearing portion 317. In this way, the lid 312 is connected to the container inner frame 21 via the shaft 315. Subsequently, by attaching the container inner frame 21 to the bottom lid 20, the lid 312 is attached to the container body 311. The lid 312 opens and closes relative to the container body 311 by rotating around the axis 315.
[0075] Next, the configuration of the hinge portion 313 will be described in detail. The bottom lid 20, container inner frame 21, lid body 40, and shaft 315 that make up the container body 311 are made of polyethylene terephthalate resin. The container-side shaft support portion 33 is a part integrally formed with the container inner frame 21, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin. Furthermore, the lid-side shaft support portion 46 is a part integrally formed with the lid body 40, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin.
[0076] The lid-side bearing portion 317 provided in the lid-side shaft support portion 46 is a circular hole into which the shaft 315 fits. The lid body 40 is entirely made of amorphous polyethylene terephthalate resin, and the inner circumferential surface of the hole in the lid-side shaft support portion 46 is also made of amorphous polyethylene terephthalate resin.
[0077] Furthermore, the main body bearing portion 316 provided in the container-side shaft support portion 33 is a circular hole into which the shaft 315 fits. The container body 311 is entirely made of amorphous polyethylene terephthalate resin, and the inner circumferential surface of the hole in the main body bearing portion 316 is also made of amorphous polyethylene terephthalate resin.
[0078] The shaft 315 is entirely composed of crystallized and whitened polyethylene terephthalate resin. Therefore, the outer circumferential surface of the shaft 315 that fits into the main body side bearing portion 316 and the lid side bearing portion 317 is composed of whitened polyethylene terephthalate resin.
[0079] The main body-side fitted shaft portion 315a of the shaft 315 is press-fitted and fixed to the inner circumferential surface of the main body-side bearing portion 316. More specifically, the main body-side fitted shaft portion 315a is press-fitted to the main body-side bearing portion 316 with sufficient force to prevent rotation. Thus, the main body-side bearing portion 316 can also be called a shaft fixing portion, as it is the part that fixes the shaft 315 to prevent rotation.
[0080] Furthermore, the lid-side fitting shaft portion 315b of the shaft 315 is press-fitted to the inner circumferential surface of the lid-side bearing portion 317. Here, the lid-side fitting shaft portion 315b is press-fitted to the lid-side bearing portion 317, which is fitted to the lid-side fitting shaft portion 315b, with sufficient force to allow it to rotate relative to the lid-side fitting shaft portion 315b. In detail, the lid-side fitting shaft portion 315b is press-fitted to the lid-side bearing portion 317 with sufficient force to provide a free-stop function that allows the lid 312 to stop at any rotational position.
[0081] Here, the shaft 315 is made of polyethylene terephthalate resin that has crystallized and turned white, and since its deterioration over time is suppressed compared to amorphous polyethylene terephthalate resin, the outer diameter of the shaft 315 does not decrease over time. This allows the press-fit state between the hole in the lid-side bearing portion 317 and the lid-side fitting shaft portion 315b to be maintained in good condition, and the free-stop function can be performed effectively. Furthermore, the press-fit state between the hole in the main body bearing portion 316 and the main body fitting shaft portion 315a can be maintained in good condition, allowing the free-stop function to be performed effectively.
[0082] The inventors of this application measured the torque required to rotate the shaft 315 relative to the bearing when the shaft 315 was whitened and when the shaft 315 was amorphous without whitening. To confirm the effect of changes over time, the inventors conducted an accelerated test in which the shaft 315 and the bearing were subjected to a 50°C environment for one week, and measured the torque after this test. As a result, the torque when shaft 315 was whitened was 9.9 (N·cm), while the torque when the shaft was amorphous was 6.3 (N·cm). The torque was higher when shaft 315 was whitened. This is thought to be because when shaft 315 was whitened, the reduction in the outer diameter of shaft 315 due to the aging of polyethylene terephthalate resin was suppressed, and the press-fit state between shaft 315 and the bearing was maintained in good condition.
[0083] Furthermore, regarding the density of the shaft 315, similar to the density measurement results in the first embodiment described above, the density of the whitened shaft 315 was higher than that of the non-whitened amorphous shaft 315.
[0084] Furthermore, the inventors of the present invention conducted tests in which the shaft 315 was rotated a predetermined number of times relative to the bearing portion and measured the amount of deformation of the outer diameter of the shaft 315, both when the shaft 315 was whitened and when the shaft 315 was not whitened and remained amorphous. As a result, when the shaft 315 was amorphous, the outer diameter decreased by 0.10 mm after the test. In contrast, when the shaft 315 was whitened, the decrease in the outer diameter after the test was limited to 0.04 mm, which was more suppressed than when the shaft 315 was amorphous. Thus, when the shaft 315 is whitened, the decrease in the outer diameter of the shaft 315 can be suppressed even after the shaft 315 has been rotated multiple times relative to the bearing. Therefore, the function of the hinge portion 313 can be maintained well for a long period of time.
[0085] The shaft 315 is formed by injecting polyethylene terephthalate resin into a mold having a cavity corresponding to the shape of the shaft 315, and then cooling the polyethylene terephthalate resin within the cavity. In detail, for example, the polyethylene terephthalate resin forming the shaft 315 is heated to 280°C to 300°C and injected into the cavity, and then whitened by adjusting the temperature during cooling within the cavity so that it is maintained at a temperature of 80°C to 100°C for a predetermined time.
[0086] Furthermore, the shaft 315 can be formed by a method other than adjusting the cooling conditions within the mold. For example, the shafts 315, which are not yet whitened, may be molded using resin molding with a mold, and then the shafts 315 may be heated to 80°C to 100°C using a heater or the like to induce whitening.
[0087] As described above, according to the third embodiment to which the present invention is applied, the container comprises a container body 311, a lid body 40 that covers the container body 311 in an openable and closable manner, and a hinge portion 313 that rotatably connects the lid body 40 to the container body 311 by a body-side bearing portion 316 and a lid-side bearing portion 317, and a shaft 315 that fits into the bearing portion. The shaft 315 is made of whitened polyethylene terephthalate resin. With this configuration, the shaft 315 is made of whitened polyethylene terephthalate resin, which suppresses changes in the size of the shaft 315. As a result, the fitting state between the shaft 315 and the main body side bearing portion 316 and the lid side bearing portion 317 can be maintained well, and the function of the hinge portion 313 can be maintained well.
[0088] Furthermore, the shaft 315 is a rod-shaped component provided separately from the container body 311 and the lid body 40, and is inserted into the bearing portion 316 on the body side and the bearing portion 317 on the lid side. With this configuration, since the shaft 315 is a rod-shaped component provided separately from the container body 311 and the lid body 40, the shaft 315 made of whitened polyethylene terephthalate resin can be easily formed. In the third embodiment described above, the shaft 315 was described as a cylindrical rod, but the shape of the shaft 315 is not limited to a circle and may be other shapes. For example, the shaft 315 may be a rectangular rod (for example, a prism with a regular polygonal cross-section).
[0089] Furthermore, the container body 311, the lid body 40, and the body-side bearing portion 316 and the lid-side bearing portion 317 are made of polyethylene terephthalate resin. With this configuration, the container body 311, lid body 40, body-side bearing part 316, lid-side bearing part 317, and shaft 315 are made of polyethylene terephthalate resin, so when disposing of the container body 311, lid body 40, body-side bearing part 316, lid-side bearing part 317, and shaft 315 do not need to be separated, resulting in good recyclability.
[0090] In the third embodiment described above, the main body side fitting shaft portion 315a of the shaft 315 is fixed to the main body side bearing portion 316, and the lid side bearing portion 317 is rotatable relative to the lid side fitting shaft portion 315b. However, the present invention is not limited thereto. For example, the lid side fitting shaft portion 315b of the shaft 315 may be fixed to the lid side bearing portion 317, and the main body side fitting shaft portion 315a may be rotatable relative to the main body side bearing portion 316. Furthermore, the main body side fitting shaft portion 315a of the shaft 315 may be rotatable relative to the main body side bearing portion 316, while the lid side bearing portion 317 may be rotatable relative to the lid side fitting shaft portion 315b. Furthermore, although the third embodiment described above assumed that the entire shaft 315 was whitened, it is also possible to configure the shaft 315 so that only the outer circumference is whitened, for example. Furthermore, in the third embodiment described above, the main body bearing portion 316 and the lid bearing portion 317 were described as being in an amorphous state that had not been whitened. However, the invention is not limited to this, and for example, at least one of the main body bearing portion 316 and the lid bearing portion 317 may be whitened.
[0091] [Fourth Embodiment] A fourth embodiment to which the present invention is applied will be described below with reference to Figure 9. In this fourth embodiment, parts configured in the same way as in the second embodiment will be denoted by the same reference numerals and their descriptions will be omitted. In the second embodiment described above, the bearing portion (main body side bearing portion 216) was whitened, but this fourth embodiment differs from the second embodiment in that the shaft 415 is whitened instead of the bearing portion.
[0092] Figure 9 is an exploded perspective view of the compact container 410 in the fourth embodiment. The compact container 410 comprises a container body 411 and a lid body 440. The compact container 410 is also provided with a hinge portion 413.
[0093] The container body 411 is equipped with a body-side bearing portion 416 in place of the body-side bearing portion 216 (Figure 6) of the second embodiment described above. Since the container body 411 is the same as the container body 211 of the second embodiment described above in terms of structure other than the body-side bearing portion 416, the same reference numerals are used for parts that are configured in the same way and their description is omitted.
[0094] Furthermore, the lid body 440 is equipped with a shaft 415 in place of the shaft 215 (Figure 6) of the second embodiment described above. Since the structure of the lid body 440 is the same as that of the lid body 240 of the second embodiment described above, the same reference numerals are used for parts that are configured in the same way and their descriptions are omitted.
[0095] The hinge portion 413, which rotatably connects the lid body 440 to the container body 411, comprises a shaft 415 extending horizontally in the left-right direction and a body-side bearing portion 416.
[0096] The main body side bearing portion 416 is provided on the left and right container side shaft support portions 233, respectively. The main body side bearing portion 416 is a hole that penetrates the container side shaft support portion 233 in the axial direction (left-right direction) of the shaft 415. The left and right inner ends of the main body side bearing portion 416 open into the rear side recess 224.
[0097] The shaft 415 is a projection that protrudes outward in the left-right direction from both the left and right sides of the lid-side shaft support portion 246. The shaft 415 is integrally formed with the lid body 440 when the lid body 440 is resin-molded in a mold. As shown in Figure 9, when the lid body 440 is in the closed position, the lower surface of the tip of the shaft 415 is provided with a shaft-side inclined portion 415a that is inclined to follow the inclined portion 224c.
[0098] Here, we will explain an example of the procedure for attaching the lid body 440 to the container body 411. First, the lid body 440 is set onto the container body 411 in the state shown in Figure 9, such that the lid-side shaft support portion 246 is housed in the rear recess 224. At this time, by moving the lid body 440 downward with the left and right shafts 415 inserted into the guide grooves 224b, the shafts 415 can be guided toward the body-side shaft bearing portion 416. Then, when the shaft-side inclined portion 415a of the shaft 415 moves downward over the inclined portion 224c, the shaft 415 fits into the body-side shaft bearing portion 416. The lid body 440 is opened and closed relative to the container body 411 by rotating around the shaft 415.
[0099] Next, the configuration of the hinge portion 413 will be described in detail. The container body 411 and the lid body 440 are made of polyethylene terephthalate resin. The container-side shaft support portion 233 is a part integrally formed with the container body 411, which is made of polyethylene terephthalate resin, and is constructed of polyethylene terephthalate resin. Furthermore, the shaft 415 is a part integrally formed with the lid body 440, which is made of polyethylene terephthalate resin, and is composed of polyethylene terephthalate resin. In detail, the shaft 415 is composed of crystallized and whitened polyethylene terephthalate resin. The parts of the lid body 440 other than the shaft 415 are composed of amorphous polyethylene terephthalate resin.
[0100] The main body bearing portion 416 is a circular hole into which the shaft 415 fits. The container body 411 is entirely made of amorphous polyethylene terephthalate resin, and the inner circumferential surface of the hole in the main body bearing portion 416 is also made of amorphous polyethylene terephthalate resin.
[0101] The lid body 440, which includes the shaft 415, is formed by injecting polyethylene terephthalate resin into the cavity of a mold and cooling the polyethylene terephthalate resin within the cavity. The shaft 415 is formed integrally with the lid body 440 during resin molding using a mold. Specifically, for example, polyethylene terephthalate resin is heated to 280°C to 300°C and injected into the cavity, and then cooled. During this process, the shaft 415 is formed by changing the cooling conditions for the parts surrounding the shaft 415. For example, when cooling the lid body 440 in the mold, while other parts are cooled slowly, the shaft 415 is kept at a temperature of 80°C to 100°C for a predetermined time, thereby forming a whitened shaft 415.
[0102] Furthermore, the shaft 415 can also be formed by a method other than adjusting the cooling conditions within the mold. For example, the lid body 440, which is in an amorphous state and has not been whitened, may be molded using resin molding with a mold, and then only the shaft 415 may be heated to 80°C to 100°C using a heater or the like to whiten the shaft 415.
[0103] As described above, according to the fourth embodiment to which the present invention is applied, the shaft 415 is integrally formed with the lid body 440. With this configuration, the portion integrally formed with the lid body 440 can be whitened to form the shaft 415 of the whitened polyethylene terephthalate resin, and the formation of the shaft 415 is easy. The shaft 415 may be integrally formed on either the container body 411 or the lid body 440, and the bearing portion may be formed on the other of the container body 411 or the lid body 440. For example, the bearing portion may be formed on the lid body 440 and the shaft on the container body 411.
[0104] Furthermore, the manufacturing method for the compact container 410 is a method for manufacturing a container comprising a container body 411, a lid body 440 that covers the container body 411 in an openable and closable manner, and a hinge portion 413 that rotatably connects the lid body 440 to the container body 411 by a body-side bearing portion 416 and a shaft 415 that fits into the body-side bearing portion 416. The shaft 415 is formed integrally with the lid body 440 by resin molding polyethylene terephthalate resin in a mold, and the shaft 415 is formed by changing the cooling conditions of the mold for the portion around the shaft 415 to whiten the polyethylene terephthalate resin. According to this manufacturing method, the shaft 415 can be easily formed because a whitened shaft 415 is formed by changing the cooling conditions of the mold for the portion surrounding the shaft 415.
[0105] Furthermore, in the manufacturing method of the compact container 410, the shaft 415 is formed integrally with the lid body 440 by resin molding polyethylene terephthalate resin in a mold, or the shaft 415 may be formed by whitening the polyethylene terephthalate resin by heating after resin molding. According to this manufacturing method, after integrally molding the shaft 415 with the lid body 440 using a mold, the molded shaft portion is heated to form a shaft 415 in which polyethylene terephthalate resin has been whitened. Therefore, the shaft 415 can be easily formed.
[0106] In the fourth embodiment described above, the main body bearing portion 416 was described as being in an amorphous state that had not been whitened. However, the invention is not limited to this, and a configuration in which the main body bearing portion 416 is also whitened in addition to the shaft 415 is also possible. [Explanation of Symbols]
[0107] 10,210,410: Compact container (container) 11,211,311,411: Container body 12,312: Lid 13,213,313,413: Hinge section 15,215,315,415: Axis 15a, 315a: Main body side fitting shaft part 15b, 315b: Lid side fitting shaft part 16,216,316,416: Main body side bearing section (bearing section) 16a,216a:hole 16b, 216b: Whitening part 17,317: Cover-side bearing section (bearing section) 17a:hole 17b: Whitening part 20: Bottom lid 21: Container inner frame 21a: Storage compartment 21b: Storage compartment 22: Bottom part 23: Bottom cover peripheral wall 24: Front wall 25: Rear wall 26: Side wall section 27: Bottom cover recess 30: Middle frame bottom wall 30a: Partition wall 31: Peripheral wall section of the central frame 31a: Middle frame rear wall 32: Flange section 32a: Rear flange section 32b: Flange-side recess 33,233: Container side shaft support part 40,240,340,440: Lid body 41: Middle frame 41a: Engagement piece 42: Mirror 44: Top panel 45: Peripheral wall part 46,246: Lid side shaft support part 46a: Notch 215a, 415a: Shaft side slope part 222: Bottom Wall 223: Main body peripheral wall part 224: Rear recess 224a: Side wall 224b: Guide groove 224c: Slope section 244: Top panel 245: Peripheral wall part K: Space
Claims
1. A container comprising a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, The bearing portion is a container made of whitened polyethylene terephthalate resin.
2. The container according to claim 1, wherein the bearing portion is integrally provided on at least one of the container body and the lid body, which are made of polyethylene terephthalate resin, and the fitting portion into which the shaft fits is an annularly whitened portion when viewed in the axial direction.
3. The container body has a body-side bearing portion into which the shaft is fitted, The lid body has a lid-side bearing portion into which the shaft fits, The container according to claim 1, wherein at least one of the main body side bearing portion and the lid side bearing portion is made of whitened polyethylene terephthalate resin as the bearing portion.
4. The shaft is integrally formed with either the container body or the lid body. The container according to claim 1, wherein the bearing portion is integrally formed with the other of the container body and the lid body.
5. The container according to any one of claims 1 to 4, wherein the shaft is made of polyethylene terephthalate resin.
6. The container according to claim 5, wherein the container body, the lid body, and the bearing portion are made of polyethylene terephthalate resin.
7. A method for manufacturing a container comprising a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, The bearing portion is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold. The bearing portion is formed by changing the cooling conditions of the mold to whiten the polyethylene terephthalate resin in the area surrounding the bearing portion.
8. A method for manufacturing a container comprising a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, The bearing portion is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold. The bearing portion is formed by heating the polyethylene terephthalate resin after the resin molding process to whiten it.
9. A container comprising a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, The aforementioned shaft is a container made of whitened polyethylene terephthalate resin.
10. The container according to claim 9, wherein the shaft is a rod-shaped component provided separately from the container body and the lid body, and is inserted into the bearing portion.
11. The container according to claim 9, wherein the shaft is integrally formed with either the container body or the lid body.
12. The container according to claim 9, wherein the container body, the lid body, and the bearing portion are made of polyethylene terephthalate resin.
13. A method for manufacturing a container comprising a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, The shaft is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold. The method for manufacturing a container is to change the cooling conditions of the mold with respect to the portion surrounding the shaft to whiten the polyethylene terephthalate resin.
14. A method for manufacturing a container comprising a container body, a lid body that covers the container body in an openable and closable manner, and a hinge portion that rotatably connects the lid body to the container body by a bearing portion and a shaft that fits into the bearing portion, The shaft is formed integrally with at least one of the container body and the lid body by resin molding polyethylene terephthalate resin in a mold. The shaft is a method for manufacturing a container formed by heating the polyethylene terephthalate resin to whiten it after resin molding.