Resin container, and method and apparatus for manufacturing resin container

Abstract

A resin container of the present invention has: a neck section that forms an inlet / outlet for contents; a bottomed cylindrical body connected to the neck section; and a conveyance holding section that is formed integrally with the body and is made of the same material as the body. The conveyance holding section forms a ring shape that includes: a flat peripheral edge section that is disposed further inward than the outer circumference of the body and extends along a container axial direction and a container radial direction; and an opening that penetrates and opens in the peripheral edge section in a direction intersecting the container radial direction.

Description

Resin container, method and apparatus for manufacturing resin container

[0001] The present invention relates to a resin container, a method for manufacturing a resin container, and a manufacturing apparatus.

[0002] Conventionally, various resin containers having a holding part for transportation have been proposed in order to improve the convenience of handling and transporting the container. In addition, as a method for manufacturing resin containers, a biaxial stretching blow method is known, which performs longitudinal stretching of a preform with a stretching rod during blow molding while performing transverse stretching with compressed air.

[0003] When the biaxial stretching blow method is applied to the manufacture of a resin container having this type of holding part for transportation, the optimal manufacturing method is appropriately selected according to the application of the container. Examples include insert molding of a handle member (e.g., Patent Document 1), a method of molding a handle member by retrofitting (e.g., Patent Document 2), a method of molding a handle integrally with a preform (e.g., Patent Document 3), and a method of forming a hollow handle on the container by blow molding (e.g., Patent Document 4).

[0004] Japanese Unexamined Patent Publication No. Hei 8-169059 Japanese Unexamined Patent Publication No. 2000-177741 Japanese Patent No. 4162776 Japanese Patent No. 7106530

[0005] The methods described in Patent Documents 1 to 4 above, in addition to having low versatility for respective containers, have problems in terms of manufacturing cost and lead time. In particular, when a handle member is prepared in advance and integrated during blow molding, the equipment cost becomes extremely high.

[0006] Accordingly, the present invention has been made in view of such problems, and an object of the present invention is to provide a resin container having a holding part for transportation that is highly versatile in shape and easy to manufacture compared to conventional ones.

[0007] A resin container according to one aspect comprises: a neck portion forming an inlet / outlet for contents; a bottomed cylindrical body portion connected to the neck portion; and a holding portion for transportation formed integrally with the body portion from the same material as the body portion. The holding portion for transportation is arranged on the inner side than the outer circumference of the body portion and has a ring shape including a flat plate-shaped peripheral edge portion along the container axial direction and the container radial direction, and an opening penetrating the peripheral edge portion in a direction intersecting the container radial direction.

[0008] According to one embodiment, a resin container can be provided that has a more versatile shape than conventional containers and a transportable holding part that is easy to manufacture.

[0009] This figure shows an example of the configuration of a resin container according to this embodiment. This is a partially enlarged view of Figure 1(a). This is a cross-sectional view taken along line A-A in Figure 2. This is a schematic diagram showing an example of the configuration of a blow molding apparatus according to this embodiment. This is a flowchart showing an example of a method for manufacturing a resin container according to this embodiment. This is an explanatory diagram of the blow molding process according to this embodiment. This is a continuation of Figure 6. This is a continuation of Figure 7. This is a continuation of Figure 8. This figure shows an example of the configuration of a blow cavity type nested type. This figure shows a modified example of the resin container according to this embodiment.

[0010] Embodiments of the present invention will be described below with reference to the drawings. In the embodiments, for the sake of clarity, structures and elements other than the main parts of the present invention will be simplified or omitted in the description. Also, the same elements will be denoted by the same reference numerals in the drawings. Note that the shapes and dimensions of each element shown in the drawings are schematic representations and do not represent the actual shapes and dimensions.

[0011] Figure 1(a) is a front view of the resin container of this embodiment, and Figure 1(b) is a top view of the resin container of this embodiment. Figure 2 is a partially enlarged view of Figure 1(a). Figure 3 is a cross-sectional view taken along line A-A in Figure 2.

[0012] The resin container 1 of this embodiment (hereinafter also simply referred to as the container) has a substantially cylindrical overall shape and comprises a neck portion 2, a body portion 3, a bottom portion 4, and a carrying portion 5. The container 1 is manufactured by biaxial stretch blow molding (stretch blow molding) as described later.

[0013] The neck portion 2 is formed in a substantially cylindrical shape with an opening at its upper end. The opening of the neck portion 2 serves as an entrance and exit for the contents of the container 1 (for example, liquids such as beverages, seasonings, oils, and detergents). In addition, a threaded portion 2a is formed on the outer surface of the neck portion 2 to allow a lid (not shown) to be attached.

[0014] The body portion 3 is connected at its upper end to the neck portion 2 and extends in a cylindrical shape along the container axis direction of the container 1 (up and down direction in Figure 1), forming the side portion of the container 1.

[0015] The bottom portion 4 is connected to the lower end of the body portion 3, closing off the lower end of the body portion 3 and forming a circular, flat bottom surface portion in the container 1. The body portion 3 and the bottom portion 4 define the storage space for the contents in the container 1.

[0016] Furthermore, in the container 1 of this embodiment, a recessed portion 6 is formed in the area near the neck portion 2 at the upper end of the body portion 3, where the body portion 3 is recessed inward in the radial direction of the container. As shown in Figure 1(b), the recessed portion 6 is formed to extend in the circumferential direction of the container in a part of the circumferential direction of the container 1. As shown in Figures 1(a) and 2, the recessed portion 6 has a shape in which the middle portion of the recessed portion 6 is recessed inward in a substantially semicircular shape in the radial direction compared to the upper and lower ends of the recessed portion 6.

[0017] The upper end of the recessed portion 6 faces the lower end of the neck portion 2, and the middle portion of the recessed portion 6 is located inward in the container diameter direction from the outer diameter end of the neck portion 2. As shown in Figures 1(a) and 2, the contour of the recessed portion 6 from the upper end to the middle portion is such that the upper end of the recessed portion 6 protrudes radially outward and then folds back inward in the container diameter direction toward the middle portion. The lower end of the recessed portion 6 is located further outward in the container diameter direction than the upper end of the recessed portion 6 and faces the outer circumference of the body portion 3. As a result, the contour of the recessed portion 6 has a shape that connects a first curved surface 6a that curves inward in an S-shape toward the container 1 from the upper end of the recessed portion 6 toward the middle portion, and a second curved surface 6b that curves in an arc shape toward the lower end of the middle portion of the recessed portion 6. Furthermore, in the radial direction of the container 1 (left-right direction in Figure 2), the part of the transport holding portion 5 that is located on the innermost side (towards the central axis of the container 1) is located on the inner side of the upper end side of the recessed portion 6 (first curved surface 6a) that protrudes on the outermost side.

[0018] As shown in Figure 1(b), the transport holding portion 5 is a ring-shaped part located at the center of the recessed portion 6 in the circumferential direction of the container. The transport holding portion 5 is formed using the resin of the preform P described later in the blow molding process and is integrally formed with the body portion 3 and the recessed portion 6 of the container 1. Furthermore, as shown in Figures 1(a) and (b), the transport holding portion 5 is positioned inward in the radial direction of the container from the outer circumference of the body portion 3.

[0019] The transport and holding portion 5 has a flat peripheral edge portion 5a along the container axial direction and the container radial direction, and a circular opening 5b that penetrates the peripheral edge portion 5a in a direction intersecting the container radial direction. The inner circumference of the peripheral edge portion 5a is connected to the recess portion 6. The transport and holding portion 5 having the opening 5b can be used, for example, as a handle when holding the container 1 with fingers, or for suspending the container 1. As an example, the diameter of the opening 5b of the transport and holding portion 5 is formed to a dimension of, for example, 1 mm to 8 mm, and preferably to a dimension of 2 mm to 6 mm. The shape of the opening 5b may be a circular shape other than a perfect circle (for example, an ellipse) or a polygonal shape.

[0020] As shown in Figure 3, the peripheral edge 5a of the transport holding section 5 is formed as a solid resin plate, except for the portion of the opening 5b. In other words, the peripheral edge 5a is configured so that there is no portion on its inside that is hollow and not welded with resin. Furthermore, at the connection point between the flat peripheral edge 5a and the body 3, a thickened portion (reinforced portion) 6c is formed along the contour of the recess 6, with a resin thickness greater than that of the peripheral edge 5a. In a cross-section perpendicular to the central axis of the container 1, the thickness of the thickened portion 6c is curved and decreases from the base end facing the body 3 toward the outer diameter side of the peripheral edge 5a. The thickened portion 6c reinforces the connection point between the body 3 and the peripheral edge 5a, and serves to prevent the peripheral edge 5a of the transport holding section 5 from breaking and detaching from the body 3.

[0021] The raw material for container 1 (or preform P) is a thermoplastic synthetic resin, which can be appropriately selected depending on the application of the container. Specific examples of materials include PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PCTA (polycyclohexanedimethylene terephthalate), Tritan (Tritan®: a polyester copolymer manufactured by Eastman Chemical Company, using cyclobutanediol as a monomer), PP (polypropylene), PE (polyethylene), PC (polycarbonate), PES (polyethersulfone), PPSU (polyphenylsulfone), PS (polystyrene), COP / COC (cyclic olefin polymer), PMMA (polymethyl methacrylate: acrylic), and PLA (polylactic acid).

[0022] Next, with reference to Figure 4, an example of the configuration of the blow molding apparatus 10 applied to the manufacture of the container 1 of this embodiment will be described. The blow molding apparatus 10 is an example of a container manufacturing apparatus and employs a hot parison method (also called a one-stage method) in which the container 1 is blow-molded by utilizing the heat retained during injection molding (internal heat quantity) without cooling the preform P to room temperature.

[0023] The blow molding apparatus 10 comprises an injection molding unit 11, a temperature control unit 12, a blow molding unit 13, a removal unit 14, and a transport mechanism 16. The injection molding unit 11, the temperature control unit 12, the blow molding unit 13, and the removal unit 14 are positioned at predetermined angles (for example, 90 degrees) around the transport mechanism 16.

[0024] (Transport mechanism 16) The transport mechanism 16 includes a transport plate (not shown) that moves in a rotational direction about an axis perpendicular to the plane of the paper in Figure 4. The transport plate is composed of a single disc-shaped flat plate member or a plurality of substantially fan-shaped flat plate members divided for each molding station. One or more neck-shaped plates 16a (not shown in Figure 4) for holding the neck portion of the preform P (or the neck portion 2 of the container 1) are arranged on the transport plate at predetermined angles.

[0025] The transport mechanism 16 includes a rotating mechanism (not shown) and moves a transport plate to transport the preform P (or container 1), whose neck is held by the neck mold 16a, in the order of injection molding section 11, temperature control section 12, blow molding section 13, and removal section 14. The transport mechanism 16 also includes a lifting mechanism (vertical mold opening and closing mechanism) and a mold opening mechanism for the neck mold 16a, and performs operations related to lifting and lowering the transport plate, as well as mold closing and mold opening (release) in the injection molding section 11, etc.

[0026] (Injection Molding Section 11) The injection molding section 11 includes an injection cavity mold and an injection core mold (not shown in the figure) and manufactures the preform P. An injection device 15 is connected to the injection molding section 11 to supply the resin material, which is the raw material for the preform P.

[0027] In the injection molding section 11, the injection cavity mold, injection core mold, and the neck mold 16a of the transport mechanism 16 are closed to form a mold space in the shape of a preform. Then, molten resin material is injected from the injection device 15 into this preform-shaped mold space, thereby manufacturing a preform P in the injection molding section 11.

[0028] Here, the overall shape of the preform P is a bottomed cylindrical shape with one end open and the other end closed. The preform P has a neck portion formed at one end with an opening, a cylindrical body portion connected to the neck portion, and a bottom portion connected to the body portion that closes the other end. The shape of the neck portion of the preform P corresponds to the neck portion 2 of the container 1.

[0029] Furthermore, even when the mold of the injection molding section 11 is opened, the neck mold 16a of the transport mechanism 16 remains closed and continues to hold and transport the preform P. The number of preforms P that are simultaneously molded in the injection molding section 11 (i.e., the number of containers that can be simultaneously molded in the blow molding apparatus 10) can be set as appropriate.

[0030] (Temperature adjustment unit 12) The temperature adjustment unit 12 is responsible for equalizing the temperature of the preform P transported from the injection molding unit 11, removing uneven heating, and adjusting the temperature distribution, thereby adjusting the temperature of the preform P to a temperature suitable for the final blowing. As an example, the temperature adjustment unit 12 adjusts the temperature of at least the body of the preform P to a temperature significantly higher than the glass transition temperature Tg of the synthetic resin material (for example, from Tg + 60°C to Tg + 90°C) and close to the melting point Tm (for example, from Tm - 70°C to Tm - 40°C).

[0031] The temperature control mold of the temperature control unit 12 includes a temperature control pot (or heating pot) for controlling the temperature of the preform P from the outside, and a temperature control rod (or heating rod) for controlling the temperature of the preform P from the inside. The temperature control mold may also have an air introduction member for introducing compressed air for cooling into the preform P instead of a temperature control rod.

[0032] (Blow molding section 13) The blow molding section 13 manufactures a container by performing biaxial stretch blow molding on the preform P whose temperature has been controlled by the temperature control section 12. Specifically, the blow molding section 13 performs preliminary blow molding on the preform P to form an intermediate P1, and then performs final blow molding on the intermediate P1 to manufacture the above-mentioned container 1. The detailed process of blow molding the container 1 in the blow molding section 13 will be described later.

[0033] As shown in Figures 6-9 described later, the blow molding section 13 comprises a core mold 21, a stretching rod 22, a blow cavity mold 23, and a bottom mold 24. The blow cavity mold 23 and the bottom mold 24 are examples of blow molding dies. The core mold 21 is an air introduction / exit member that can move up and down (in the Y direction described later) relative to the preform P supported by the neck mold 16a, and is responsible for introducing / exiting compressed air to the preform P or intermediate body P1. The stretching rod 22 is arranged on the inner circumference of the core mold 21 so as to be movable in the vertical direction, and is responsible for stretching the preform P along the vertical axis.

[0034] The blow cavity mold 23 is a pair of split molds that define the shape of the body 3 of the container 1, and is configured to open and close horizontally (in the Z direction, as described later). The bottom mold 24 is a mold that defines the shape of the bottom 4, and is positioned to be movable vertically relative to the blow cavity mold 23 when it is closed.

[0035] Furthermore, a pair of nesting molds 25 that define the shapes of the transport-holding portion 5 and the recessed portion 6 are detachably arranged in the blow cavity mold 23 at positions corresponding to the transport-holding portion 5 and the recessed portion 6. By forming the transport-holding portion 5 and the recessed portion 6 with nesting molds 25, the shapes of the transport-holding portion 5 and the recessed portion 6 can be flexibly changed by replacing the nesting molds 25.

[0036] Figure 10 shows an example configuration of a nesting mold 25 arranged in a blow cavity mold 23. Note that only one side of the nesting mold 25 is shown in Figure 10, and the illustration and redundant explanation of the other side of the nesting mold 25 are omitted.

[0037] As shown in Figure 10, the nesting mold 25 includes a circular first cutting portion 25a that forms the opening 5b of the transport and holding portion 5, and a second cutting portion 25b that defines the shape of the outer edge of the peripheral portion 5a of the transport and holding portion 5. The nesting mold 25 also includes a main body portion 25c having a mold surface corresponding to the shape of the peripheral portion 5a of the transport and holding portion 5, a recess-forming portion 25d having a mold surface that is substantially perpendicular to the mold surface of the main body portion 25c and has a shape that connects the first curved surface 6a and the second curved surface 6b, and a rounded portion 25e formed at the part connecting the mold surface of the main body portion 25c and the mold surface of the recess-forming portion 25d.

[0038] (Removal section 14) The removal section 14 is configured to release the neck portion 2 of the container 1 manufactured in the blow molding section 13 from the neck mold 16a and remove the container to the outside of the blow molding apparatus 10.

[0039] Next, the method for manufacturing the container 1 using the blow molding apparatus 10 of this embodiment will be described. Figure 5 is a flowchart showing the steps of the manufacturing method for the container 1.

[0040] (Step S101: Injection Molding Process) First, in the injection molding section 11, resin is injected from the injection device 15 into a mold space in the shape of a preform formed by the injection cavity mold, the injection core mold, and the neck mold 16a of the transport mechanism 16, and a preform P is manufactured. Then, after the injection (filling and holding pressure) of the resin material is completed, or after a minimum cooling time provided after the completion of injection, the injection mold of the injection molding section 11 is opened.

[0041] Although there is no particular limitation, from the viewpoint of manufacturing containers in a high-speed molding cycle, in step S101, it is preferable to perform mold opening without providing a cooling time for the preform P in the injection mold after completion of injection (filling and pressure holding) of the resin material. On the other hand, when minimal cooling of the preform P is performed in the injection mold, it is preferable that the time for cooling the resin material (cooling time) after completion of injection of the resin material in the injection molding section 11 is 1 / 2 or less of the time for injecting the resin material (injection time). Furthermore, the cooling time described above can be made shorter relative to the injection time of the resin material, depending on the weight of the resin material. For example, the cooling time is more preferably 2 / 5 or less, further preferably 1 / 4 or less, and particularly preferably 1 / 5 or less of the injection time of the resin material.

[0042] When injection molding of the preform P is completed, the mold of the injection molding section 11 is opened, and the preform P is released from the injection cavity mold and the injection core mold. Next, the transfer plate of the conveyance mechanism 16 moves to rotate by a predetermined angle, and the preform P held by the neck mold 16a is conveyed to the temperature adjustment section 12 while retaining the heat it retained during injection molding.

[0043] (Step S102: Temperature adjustment step) Subsequently, in the temperature adjustment section 12, the preform P is housed in a temperature adjustment mold, and temperature adjustment is performed to bring the temperature of the preform P close to a temperature suitable for final blow molding. The temperature of the preform P is adjusted to be higher than the temperature when the preform P is released from the injection molding section 11, and as described above, the temperature is adjusted to be significantly higher than the glass transition temperature Tg of the synthetic resin that is the material (for example, Tg + 60°C to Tg + 90°C), and close to the melting point Tm (for example, Tm - 70°C to Tm - 40°C).

[0044] After the temperature adjustment step, the transfer plate of the conveyance mechanism 16 moves to rotate by a predetermined angle, and the temperature-adjusted preform P held by the neck mold 16a is conveyed to the blow molding section 13.

[0045] The blow molding process in the blow molding section 13 will be described below, with reference to Figures 6-9 as appropriate. In Figures 6-9, the XYZ coordinate system is shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the X direction is the left-right direction (width direction) in Figures 6-9, and the Y direction is the up-down direction (height direction) in Figures 6-9, and is perpendicular to the X direction. The Z direction is the vertical direction (depth direction) of the paper in Figures 6-9, and is perpendicular to both the X and Y directions.

[0046] (Step S103: Forming of the intermediate body) Next, the preform P is placed in the blow molding section 13, and with the blow cavity mold 23 open, the core mold 21 descends relative to the preform P. As a result, the air introduction / exit member comes into contact with the neck of the preform P. After that, the stretching rod 22 is inserted into the preform P. Then, while the preform P is stretched in the longitudinal axis with the stretching rod 22 which is positioned radially inward from the core mold 21, low-pressure (e.g., 0.05 MPa to 0.20 MPa) preliminary blow air is introduced into the preform P from the core mold 21 to expand the preform P to a predetermined size. As a result, as shown in Figure 6, an intermediate body P1 is formed that is expanded in the longitudinal and transverse axes compared to the preform P shown by the dashed line. The size of the intermediate body P1 is set to be slightly smaller than that of the container, for example. For example, the diameter of the intermediate body P1 in the part where the transport holding part 5 is formed is set to be 70% to 90% of the diameter of the corresponding part in the container 1. Furthermore, in the molding of the intermediate P1, air is introduced into the preform P under lower pressure and lower flow rate conditions compared to the blow molding described later.

[0047] (Step S104: Molding of carrying holding portion) Next, in the blow molding unit 13, from the state before mold clamping of the blow cavity mold 23 shown in FIG. 7, the blow cavity mold 23 is clamped in the Z direction in the figure in a state where the intermediate P1 is accommodated inside. Then, by the mold clamping of the blow cavity mold 23, the resin of the intermediate P1 is sandwiched and compressed between the portions of the pair of insert molds 25 respectively disposed on the blow cavity mold 23 that is a pair of split molds. As a result, as shown in FIG. 8, a portion corresponding to the flat-plate-shaped carrying holding portion 5 is formed on the intermediate P1. Note that the bottom mold 24 waits at a lower position that does not contact the bottom of the preform P before the mold clamping of the blow cavity mold 23, and is controlled to quickly rise to the molding position before or after the mold clamping.

[0048] When the blow cavity mold 23 is clamped, the resin of the intermediate P1 is sandwiched between the main body portions 25c of the pair of insert molds 25, whereby the flat-plate-shaped carrying holding portion 5 having a predetermined thickness is formed. At this time, the second cutting portions 25b of the pair of insert molds 25 abut against each other, so that the outer edge of the peripheral edge portion 5a of the carrying holding portion 5 is formed in a predetermined shape, and the first cutting portions 25a of the pair of insert molds 25 abut against each other, whereby the opening 5b is formed in the carrying holding portion 5.

[0049] Further, a rounded portion 25e is provided at a portion connecting the mold surface of the recess forming portion 25d of the insert mold 25 and the mold surface of the main body portion 25c (a corner portion between the mold surface of the recess forming portion 25d and the mold surface of the main body portion 25c), and the mold surface of the recess forming portion 25d and the mold surface of the main body portion 25c are connected in a curved surface shape. Therefore, when the blow cavity mold 23 is clamped, the resin of the intermediate P1 moves into the space of the rounded portion 25e (is pushed thereinto) and the space is filled with the resin, whereby a thick portion (built-up portion) 6c is formed at the connecting portion between the peripheral edge portion 5a and the body portion 3.

[0050] Further, when the blow cavity mold 23 is clamped, the resin of the intermediate P1 may be brought into close contact with the mold surface of the recess forming portion 25d of the insert mold 25, and a portion (primary shape portion) constituting a part of the recess portion 6 may be formed on the intermediate P1 at a position near the parting surfaces of the blow cavity mold 23 and the insert mold 25. Thereafter, the intermediate P1 having the above-described primary shape portion may be shaped into a final shape by blow air.

[0051] Furthermore, the thickened portion (built-up portion) 6c may be formed using blow air (described later). Alternatively, when closing the blow cavity mold 23, a primary shape portion constituting a part of the thickened portion (built-up portion) 6c may be formed on the intermediate body P1, and the intermediate body P1 having the primary shape portion may be shaped into the final shape using blow air.

[0052] Furthermore, the transport holding portion 5 formed in the intermediate body P1 does not necessarily have to have an opening 5b; the position of the opening 5b may be closed off by a resin piece that can be removed in a later process.

[0053] (Step S105: Blow molding of the container) In the blow molding section 13, with the intermediate body P1 on which the transport holding section 5 is formed, the bottom of the intermediate body P1 is held down by the stretching rod 22 and the bottom mold 24, and while further longitudinal stretching is performed as needed, high-pressure blow air (e.g., 0.30 MPa - 3.5 MPa) is supplied from the air introduction / exit member, and the intermediate body P1 is stretched horizontally by the blow air. The blow air used to form the container from the intermediate body P1 is introduced into the intermediate body P1 under conditions of higher pressure and higher flow rate compared to the air used to mold the intermediate body P1. As a result, as shown in Figure 9, the intermediate body P1 expands and is formed to closely fit into the mold space of the blow cavity mold 23 and the nesting mold 25, and is blow molded into the container 1.

[0054] When the intermediate body P1 is stretched horizontally with blow air, the resin near the neck of the intermediate body P1 (or the primary shape of the recessed portion 6) comes into close contact with the mold surface of the recess-forming portion 25d of the nesting mold 25 and the mold surface of the recess-forming portion on the blow cavity mold 23 side. As a result, in the body portion 3 of the container 1, a recessed portion 6 is formed at the connection point with the transport-holding portion 5, following the mold surface of the recess-forming portion 25d.

[0055] Furthermore, if the primary shape of the thickened portion (build-up portion) is formed in the intermediate body P1, when the intermediate body P1 is stretched laterally with blow air, the primary shape of the thickened portion (build-up portion) 6c may be pressed against the space of the rounded portion 25e to form the thickened portion (build-up portion) 6c at the connection point between the peripheral portion 5a and the body portion 3. Also, if the primary shape of the thickened portion (build-up portion) is not present in the intermediate body P1, when the intermediate body P1 is stretched laterally with blow air, resin may be filled into the space of the rounded portion 25e to form the thickened portion (build-up portion) 6c at the connection point between the peripheral portion 5a and the body portion 3.

[0056] Although not particularly limited, after shaping the intermediate P1 into the shape of the container 1, a cooling blow process may be further carried out in which cooling air at atmospheric pressure is circulated inside the container 1 to rapidly lower the temperature of the container 1. Note that the molding of the intermediate P1 (S103), the molding of the transport and holding part 5 (S104), and the blow molding of the container (S105) are examples of blow molding processes performed in the blow molding section 13.

[0057] (Step S106: Removal Process) When the blow molding of the container 1 is completed, the blow cavity mold 23 is opened. This allows the container 1 to move out of the blow molding section 13. Next, the transfer plate of the transport mechanism 16 moves by a predetermined angle, and the container 1 is transported to the removal section 14. In the removal section 14, the neck portion 2 of the container 1 is released from the neck mold 16a, and the container 1 is removed to the outside of the blow molding apparatus 10.

[0058] This completes one container manufacturing cycle in the method for manufacturing container 1. Subsequently, by moving the transfer plate of the transport mechanism 16 by a predetermined angle, each of the steps S101 to S106 described above is repeated. When the blow molding apparatus 10 is in operation, the manufacturing of four sets of containers, each with a time difference between each step, is performed in parallel. Also, due to the structure of the blow molding apparatus 10, the injection molding step (S101), temperature adjustment step (S102), blow molding steps (S103 to S105), and removal step (S106) are all the same length. Similarly, the transport time between the above steps is also the same length.

[0059] The effects of this embodiment are described below. The container 1 of this embodiment has a neck portion 2 that forms an entrance and exit for the contents, a bottomed cylindrical body portion 3 connected to the neck portion 2, and a carrying and holding portion 5 formed integrally with the body portion 3 from the same material as the body portion 3. The carrying and holding portion 5 is ring-shaped and includes a flat peripheral edge portion 5a positioned inside the outer circumference of the body portion 3 and aligned with the container axial direction and the container radial direction, and an opening 5b that penetrates the peripheral edge portion 5a in a direction intersecting the container radial direction. In the container 1 of this embodiment, the ring-shaped carrying and holding portion 5 including the flat peripheral edge portion 5a and the opening 5b is formed integrally with the body portion 3 at a position inside the outer circumference of the body portion 3. The carrying and holding portion 5 can be applied to multiple uses such as a handle when holding the container 1 and suspending the container 1, and its shape makes it easy to clean, thus ensuring the high versatility of the container 1.

[0060] Furthermore, in this embodiment, the transport and holding portion 5 in the container 1 can be integrally molded with the body portion 3 during the blow molding process by compressing the intermediate body P1, which is formed by expanding the preform P, between the blow cavity mold 23. Also, since the transport and holding portion 5 is located inside the outer circumference of the body portion 3, there is no need to pull the material of the portion of the intermediate body P1 that forms the transport and holding portion 5 radially outward. Therefore, according to this embodiment, the transport and holding portion 5 can be easily formed in the container 1 without adding any new equipment to a general blow molding apparatus 10.

[0061] The present invention is not limited to the embodiments described above, and various improvements and design modifications may be made without departing from the spirit of the invention.

[0062] In the above embodiment, an example was described in which the transport holding portion 5 is formed near the neck portion 2 (on the upper end side of the container 1), but the arrangement of the transport holding portion 5 in the container 1 is not limited to the above. For example, as shown in Figure 11, the transport holding portion 5 may be provided at a different position, such as near the bottom portion 4 of the container 1. Alternatively, multiple transport holding portions 5 may be formed at different locations on a single container 1.

[0063] Furthermore, in the above embodiment, an example was described in which the container 1 is manufactured using a hot parison type (one-stage type) blow molding apparatus 10. However, the container 1 may also be manufactured using a cold parison type (two-stage type) blow molding apparatus, which heats a preform cooled to room temperature and then performs blow molding.

[0064] Furthermore, in the above embodiment, an example was described in which the pre-blow process (Figure 6) for forming the intermediate body P1 and the final blow molding process (Figures 7-9) for forming the container 1 are sequentially performed within the same module in the blow molding section 13 of the blow molding apparatus 10. However, in the blow molding apparatus 10, the pre-blow process (Figure 6) and the final blow molding process (Figures 7-9) may be performed in modules located at different positions, and the preform P may be transported between the two modules. In the above case, for example, the blow molding apparatus disclosed in Japanese Patent No. 6952022 may be applied.

[0065] Furthermore, in the above embodiment, an example was described in which an insert mold 25 is attached to the blow cavity mold 23 and the transport-holding portion 5 and recessed portion 6 are formed in the blow molding section 13. However, the blow cavity mold 23 and the insert mold 25 may be formed integrally, and the blow cavity mold 23 itself may have a mold surface for forming the transport-holding portion 5 and recessed portion 6.

[0066] Furthermore, the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included.

[0067] 1...Container, 2...Neck, 3...Body, 4...Bottom, 5...Holding part for transport, 5a...Peripheral part, 5b...Opening, 6...Recessed part, 6a...First curved surface, 6b...Second curved surface, 6c...Thick-walled part, 10...Blow molding apparatus, 11...Injection molding section, 12...Temperature control section, 13...Blow molding section, 14...Removal section, 15...Injection device, 16...Conveying mechanism, 16a...Neck type, 21...Core type, 22...Stretching rod, 23...Blow cavity type, 24...Bottom type, 25...Nesting type, 25a...First cutting section, 25b...Second cutting section, 25c...Main body, 25d...Recess forming section, 25e...Rounded processing section, P...Preform, P1...Intermediate

Claims

1. A resin container having a neck portion that forms an entrance and exit for the contents, a bottomed cylindrical body portion connected to the neck portion, and a transport / holding portion formed integrally with the body portion from the same material as the body portion, wherein the transport / holding portion is a ring-shaped resin container having a flat plate-shaped peripheral edge portion positioned inward from the outer circumference of the body portion and along the container axis direction and the container diameter direction, and an opening that penetrates the peripheral edge portion in a direction intersecting the container diameter direction.

2. The resin container according to claim 1, wherein the body portion has a recess that extends in the circumferential direction of the container and is recessed inward in the radial direction of the container, and the transport holding portion is formed at the center of the recess in the circumferential direction of the container.

3. The resin container according to claim 1, wherein the neck side and bottom side of the recessed portion are connected to the body portion in a curved manner.

4. A method for manufacturing a resin container having a ring shape, comprising: a neck portion that forms an entrance and exit for contents; a bottomed cylindrical body portion connected to the neck portion; and a transport / holding portion formed integrally with the body portion from the same material as the body portion, wherein the transport / holding portion is positioned inward from the outer circumference of the body portion and includes a flat plate-shaped peripheral edge portion that is aligned in the container axis direction and the container diameter direction, and an opening that penetrates the peripheral edge portion in a direction intersecting the container diameter direction, the manufacturing method comprising: a step of forming an intermediate body by introducing compressed air into a preform while longitudinally stretching a preform with a blow molding die corresponding to the shape of the resin container in an open state; a step of closing the blow molding die and sandwiching a part of the intermediate body with the blow molding die to form a corresponding portion of the transport / holding portion into the intermediate body; and a step of further introducing compressed air into the intermediate body having the corresponding portion of the transport / holding portion to shape it into the resin container.

5. A manufacturing apparatus for a resin container having a ring shape, comprising: a neck portion that forms an entrance and exit for contents; a bottomed cylindrical body portion connected to the neck portion; and a transport / holding portion formed integrally with the body portion from the same material as the body portion, wherein the transport / holding portion is positioned inward from the outer circumference of the body portion and includes a flat plate-shaped peripheral edge portion that is aligned in the container axial direction and the container radial direction, and an opening that penetrates the peripheral edge portion in a direction intersecting the container radial direction, wherein the apparatus comprises a blow molding section having a blow molding die corresponding to the shape of the resin container, wherein the blow molding section, with the blow molding die open, stretches a preform along the longitudinal axis and introduces compressed air into the preform to form an intermediate body, closes the blow molding die and sandwiches a part of the intermediate body with the blow molding die to form a corresponding portion of the transport / holding portion into the intermediate body, and further introduces compressed air into the intermediate body having the corresponding portion of the transport / holding portion to form the resin container.

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