Hollow article molding method and molding apparatus and hollow article

A hollow article is molded in a state where an inner surface of a neck portion including an inner screw portion is held by an inner neck mold, and then, the hollow article is demolded from the inner neck mold by inserting an ejection rod into the hollow article to be engaged with an inner surface of the hollow article and rotating the hollow article together with the ejection rod.

TECHNICAL FIELD

The present invention relates to a method for molding a hollow article having a screw portion (inner screw portion) on an inner surface (inner side) of a neck portion thereof, an apparatus for molding the hollow article, and the hollow article.

BACKGROUND ART

Conventionally, for example, many containers containing beverages or the like have a screw portion (outer screw portion) on an outer surface (outer side) of a neck portion thereof, and are closed by a cap mounted on the outer side of the neck portion having the outer screw portion. Further, there are not only containers which include the outer screw portion, but also containers which include a screw portion (inner screw portion) on an inner surface (inner side) of a neck portion and are closed by a cap mounted in the neck portion.

In addition to containers, some of various hollow articles having a space inside have an inner screw portion formed on an inner side of a neck portion thereof. Since the inner screw portion is a so-called undercut, it may be difficult to demold the neck portion from a mold that forms the inner screw portion when molding the hollow article including the inner screw portion.

A hollow article such as a container is formed by, for example, forming a preform by injection molding and then blow molding the preform. In this case, the inner screw portion of the neck portion is formed when injection molding the preform. Although the neck portion may be demolded after the injection molding of the preform (before the blow molding) from a mold by which the inner screw portion is formed, the neck portion may be demolded after the hollow article is formed by the blow molding from the mold by which the inner screw portion is formed (see, for example, Patent Literature 1).

The invention disclosed in Patent Literature 1 employs a neck mold having an inner and outer double structure including an outer neck mold that forms an outer surface of a neck portion and an inner neck mold that forms an inner surface of the neck portion including an inner screw portion. When injection molding the preform, the neck portion including the inner screw portion is formed, and the preform is blow molded in a state where the inner surface of the neck portion is held by the inner neck mold to form a container that is a hollow article. Thereafter, a roller is abutted against a body portion of the container to rotate the container, that is, the container itself is rotated, thereby demolding the neck portion from the inner neck mold.

By adopting such a method to demold the neck portion from an inner core mold, the hollow article such as the container can be successfully demolded from the inner neck mold while preventing deformation of the inner screw portion.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

However, when the hollow article is rotated by the method described above, if rigidity of the hollow article against which the roller abuts is low, the hollow article may be deformed, and the neck portion may not be appropriately demolded from the inner neck mold due to the deformation.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for molding a hollow article, an apparatus for molding a hollow article, and a hollow article in which, when molding the hollow article including an inner screw portion, the hollow article can be successfully demolded from a neck mold that forms the inner screw portion.

Solution to Problem

According to an aspect of the present invention for solving the above problem, there is provided a method for molding a hollow article, the hollow article including a neck portion opened on one end side thereof and a body portion connected to the neck portion, and an inner screw portion being formed on an inner surface of the neck portion, the method including: molding the hollow article in a state where the inner surface of the neck portion including the inner screw portion is held by an inner neck mold, and then; demolding the hollow article from the inner neck mold by inserting an ejection rod into the hollow article to be engaged with an inner surface of the hollow article and rotating the hollow article together with the ejection rod.

Here, in a case where the hollow article includes a small-diameter portion having an inner diameter smaller than that of the neck portion and connected to the neck portion and the body portion, it is preferable that an opening shape of the small-diameter portion is formed in a non-circular shape, and the ejection rod is engaged with the hollow article by inserting the ejection rod having a cross-sectional shape substantially the same as the opening shape of the small-diameter portion into the small-diameter portion.

It is preferable that the opening shape of the small-diameter portion is formed in a polygonal shape or a circular shape having a convex portion that protrudes inwardly.

It is preferable that, when the hollow article is rotated by the ejection rod, a tip end surface of the ejection rod is caused to abut against the hollow article to press the hollow article.

According to another aspect of the present invention, there is provided an apparatus for molding a hollow article, the hollow article including a neck portion opened on one end side thereof and a body portion connected to the neck portion, and an inner screw portion being formed on an inner surface of the neck portion, the apparatus including: a molding part configured to mold the hollow article in a state where the inner surface of the neck portion including the inner screw portion is held by an inner neck mold; and a take-out part configured to demold the hollow article from the inner neck mold, in which the take-out part includes an ejection rod including an engagement portion rotatably inserted into the hollow article and engaged with an inner surface of the hollow article during rotation.

Here, it is preferable that the engagement portion is configured to engage with the inner surface of the hollow article when the ejection rod is rotated to one side.

It is preferable that the ejection rod includes an ejection piece whose tip end surface abuts against the hollow article and which is movable in an axial direction of the ejection rod, and a biasing member which biases the ejection piece to a tip end side of the ejection rod.

It is preferable that the ejection piece includes the engagement portion.

According to another aspect of the present invention, there is provided a hollow article including: a neck portion opened on one end side thereof and to which an inner screw portion is formed on an inner surface thereof; a body portion connected to the neck portion; and a small-diameter portion having an inner diameter smaller than that of the neck portion and connected to the neck portion and the body portion, in which an opening shape of the small-diameter portion is a non-circular shape.

More specifically, it is preferable that the opening shape of the neck portion is a polygonal shape or a circular shape having a convex portion that protrudes inwardly.

Advantageous Effects of Invention

According to the present invention, when molding the hollow article including the neck portion on which the inner screw portion is formed, the hollow article can be successfully demolded from the mold. In particular, the neck portion of the hollow article can be successfully demolded from the inner neck mold that forms the inner surface of the neck portion including the inner screw portion.

DESCRIPTION OF EMBODIMENTS

The present invention relates to a method for molding a hollow article having a screw portion (inner screw portion) on an inner surface (inner side) of a neck portion thereof, an apparatus for molding the hollow article, and the hollow article. Here, the hollow article refers to an article having a space therein, and includes, for example, a container that stores beverages or the like, a cap that closes the container, and a preform for blow molding the container. The hollow article in the present embodiment is, for example, a container for storing a liquid or the like.

FIG.1is a view showing an example of a container that is a hollow article according to the present invention, in which (a) is a top view, and (b) is a longitudinal cross-sectional view.FIG.2is a longitudinal cross-sectional view of a preform for blow molding the container.

A container10, which is the hollow article shown inFIG.1, is formed of, for example, a resin material such as polypropylene, polyethylene, or polyethylene terephthalate, and is hollow so as to be able to store a liquid or the like. The container10includes a cylindrical neck portion11opened on one end side (upper end side) thereof, a cylindrical body portion12connected to the neck portion11, and a bottom portion13continuous from the body portion12. Further, the container10includes a small-diameter portion14connected to a bottom surface (reduced-diameter portion that extends in an inner diameter direction)11aof the neck portion11and having an inner diameter smaller than that of the neck portion11. The body portion12is formed with an inner diameter larger than that of the small diameter portion14, and in the present embodiment, is formed with an inner diameter larger than that of the neck portion11. A size of the inner diameter of the body portion12is not particularly limited, and the body portion12may be formed with an inner diameter smaller than that of the neck portion11.

An inner screw portion16, which is a female screw, is formed on an inner surface11bof the neck portion11. That is, on the inner surface11bof the neck portion11, a screw thread (projection)17that constitutes the inner screw portion16is provided in a spiral shape protruding toward an inner side of the neck portion11. Although not shown in the drawings, the neck portion11is mounted with a mounting member including an outer screw portion that is a male screw, so that the container10is closed.

A protruding portion18is formed on the bottom surface11aof the neck portion11. The protruding portion18protrudes from the bottom surface11aof the neck portion11toward an opening side (upward in the drawing), and is continuously provided along a circumferential direction of the neck portion11.

When the mounting member (not shown) is mounted to the neck portion11, the protruding portion18abuts against the mounting member and functions as a seal material that closes a gap between the protruding portion18and the container10. Further, the protruding portion18is provided to protrude from the bottom surface11aof the neck portion11in a curved shape (for example, a waveform) instead of a linear shape. A shape of the protruding portion18is not particularly limited, and may be any shape that can exert a function as the seal material.

Here, the small-diameter portion14of the container10has an outer diameter smaller than that of the neck portion11, and an opening shape of the small-diameter portion14(cross-sectional shape of the inner diameter of the small-diameter portion14) is a non-circular shape (a shape other than a circle), for example, a polygonal shape. In the present embodiment, the opening shape of the small-diameter portion14is octagonal.

As will be described below, the container10having such a shape is formed by first forming a preform by injection molding and blow molding the preform. In this case, by forming the small-diameter portion14into the above-described opening shape, the container10can be successfully demolded from a mold when the container10is molded.

As shown inFIG.2, a preform20for blow-molding the container10includes a neck portion21opened at one end (upper end) side thereof, a body portion22that is continuous with the neck portion21, and a bottom portion23that is continuous with the body portion22.

The neck portion21of the preform20is a portion common to the neck portion11of the container10that is a final product, and has the same shape. That is, the neck portion11of the container10is substantially formed by injection molding. In the present embodiment, a protruding portion24(18) is formed on a bottom surface21a(11a) of the neck portion21(11) of the preform20, and an inner screw portion25(16) is formed on an inner surface21b(11b) thereof.

The small-diameter portion14of the container10is also substantially formed by injection molding. That is, a connection portion20abetween the body portion22and the neck portion21, which is a portion corresponding to the small-diameter portion14in the preform20, is formed in a shape same as that of the small-diameter portion14, and in the present embodiment, the opening shape is octagonal.

Next, an injection blow molding apparatus that is a molding apparatus for molding the container10that is the hollow article will be described.FIG.3is a block diagram showing an example of a schematic configuration of the injection blow molding apparatus according to the present embodiment.FIG.4is a cross-sectional view showing a schematic configuration of an injection molding mold.FIG.5is a cross-sectional view showing a schematic configuration of a blow molding mold.

As shown inFIG.3, an injection blow molding apparatus30according to the present embodiment is a so-called one-stage (hot parison system) injection blow molding apparatus, and includes, an injection molding part50, a temperature adjustment part60, a blow molding part70, and an take-out part80.

As shown inFIG.4, the injection molding part50includes an injection molding mold51to which an injection device100is connected, and injection molds the preform20having the predetermined shape by using the injection molding mold51.

The injection molding mold51includes a neck mold52, an injection cavity mold53, and an injection core mold54. An injection space55is formed by the neck mold52, the injection cavity mold53, and the injection core mold54. The preform20having the predetermined shape is formed in the injection space55by filling a resin material as a raw material via a gate56provided at a center of a bottom portion of the injection cavity mold53. Since the configuration for injecting the resin material including the injection device100is an existing configuration, a detailed description thereof will be omitted here.

The neck mold52according to the present embodiment is configured as an inner neck mold that forms an inner surface of the neck portion21of the preform20. Specifically, the neck mold52forms a part (outer peripheral portion) of the inner surface21band the bottom surface21aof the neck portion21including the inner screw portion25(seeFIG.2).

The injection cavity mold53forms outer surfaces of the body portion22and the bottom portion23of the preform20. Further, the injection cavity mold53surrounds outside of the neck mold52, and forms an outer surface of the neck portion21. That is, the injection cavity mold53forms the outer surface of the neck portion21together with the outer surfaces of the body portion22and the bottom portion23of the preform20.

The injection core mold54forms an inner surface of the preform20. Specifically, the injection core mold54is disposed on an inner side of the neck mold52, and forms a part (central portion: inner peripheral portion) of the bottom surface21aof the neck portion21together with an inner surface of the body portion22of the preform20. Further, a space portion59, which constitutes a part of the injection space55and forms the protruding portion24, is formed at a boundary portion between the injection core mold54and the neck mold52.

Here, as described above, the opening shape of the small-diameter portion14of the container10is octagonal, and an opening shape of the connection portion20aof the preform20corresponding to the small-diameter portion14is also octagonal. In the present embodiment, an opening shape of the body portion22of the preform20is circular.

In the injection molding portion50, the preform20is injection molded using the injection molding mold51. Thereafter, the injection cavity mold53and the injection core mold54are separated from the preform20. That is, the preform20is demolded from the injection cavity mold53and the injection core mold54. Then, the neck portion21of the preform20is in a state of being held by the neck mold52. In this state, the preform20is conveyed from the injection molding part50to the temperature adjustment part60.

In the temperature adjustment part60, a temperature of the body portion22of the preform20is adjusted to a predetermined temperature suitable for blow molding. The preform20adjusted to the predetermined temperature is conveyed from the temperature adjustment part60to the blow molding part70in a state where the preform20is also held by the neck mold52here.

The blow molding part70includes, for example, a blow molding mold71shown inFIG.5. The blow molding mold71is a mold for blow molding the preform20held by the neck mold52common to the injection molding mold51, and includes a blow cavity mold72, a bottom mold73, and a blow core mold74.

The blow cavity mold72includes a pair of split molds, and has a blow cavity75that is a space in which the body portion22of the preform20is stored. The bottom mold73forms a bottom portion of the blow cavity75. That is, the bottom mold73is provided corresponding to the bottom portion23of the preform20, and forms the bottom portion13of the container10.

The blow cavity mold72according to the present embodiment includes a concave portion76in which the neck portion21of the preform20is stored, and the outer surface of the neck portion21stored in the concave portion76is supported by the blow cavity mold72. That is, the blow cavity mold72surrounds outside of the neck portion21. In a state where the neck mold52is positioned to abut against the blow cavity mold72, the outer surface of the neck portion21is supported by the blow cavity mold72.

In the state where the neck mold52is positioned to abut against the blow cavity mold72, a minute gap may be formed between the outer surface of the neck portion21of the preform20and the blow cavity mold72.

The blow core mold74includes a supply hole77for supplying blow air into the preform20, and is disposed on an inner side the neck mold52. The blow core mold74is inserted into the neck portion21of the preform20, whereby the neck portion21is closed by the neck mold52and the blow core mold74. In the present embodiment, the blow core mold74is inserted into the neck portion21and the connection portion20aof the preform20.

Although not shown in the drawings, a supply path through which a temperature adjustment medium or a cooling medium is supplied is formed in the blow cavity mold72including the pair of split molds. When stretched and brought into contact with an inner wall surface of the blow cavity mold72, the preform20disposed in the blow cavity75is adjusted (for example, cooled) to a predetermined temperature.

In the blow molding part70, high pressure air (blow air) is supplied to inside of the preform20disposed in the blow molding mold71via the supply hole77of the blow core mold74, whereby the body portion22of the preform20is extended in a vertical axis direction and a horizontal axis direction. Accordingly, the body portion12of the container10is formed. That is, the container10having a predetermined shape that is a final product is molded (seeFIG.1). If necessary, a stretching rod (not shown) may be inserted into the supply hole77of the blow core mold74and driven in the vertical axis direction.

In the blow molding part70, the blow-molded container10is then demolded from the blow cavity mold72and the blow core mold74. Next, in a state where the inner surface of the neck portion11of the container10is held by the neck mold52, the container10is conveyed from the blow molding part70to the take-out part80.

In the take-out part80, the container10, which is the hollow article, is demolded from the neck mold52and is taken out to outside of the injection blow molding apparatus30. Specifically, as shown inFIG.6, the take-out part80includes an ejection rod81. Although not shown in the drawings, the ejection rod81can be lifted and lowered by a lifting device, and is configured to be lowered from above the neck mold52and inserted into the container10.

In the present embodiment, the ejection rod81includes a rod-shaped rod member82, and includes an ejection piece83mounted on the rod member82, and a biasing member84. A mounting portion85having a diameter smaller than those of other portions is formed on a tip end side of the rod member82. The ejection piece83and the biasing member84are mounted on the mounting portion85.

The ejection piece83includes an engagement portion86that engages with an inner surface of the container10, and an abutment portion87that abuts against the bottom surface11aof the neck portion11. The engagement portion86has a cross-sectional shape (for example, an octagon) substantially the same as the opening shape of the small-diameter portion14of the container10to an extent that the engagement portion86is loosely fitted in the small-diameter portion14. The abutment portion87has a diameter larger than an outer diameter of the small-diameter portion14, and a tip end surface87aof the abutment portion87abuts against the bottom surface11aof the neck portion11. In a case where a large force is required when the container10is demolded or the like, the engagement portion86may have a size that enables the engagement portion86to abut against (engage with) the small-diameter portion14.

The ejection piece83is mounted movably in an axial direction without rotating with respect to the rod member82. In the present embodiment, as shown inFIG.7, a cross-sectional shape of the mounting portion85of the rod member82is polygonal (for example, quadrangular). In the ejection piece83, a through hole88into which the mounting portion85is inserted is formed in a polygonal (for example, quadrangular) opening shape corresponding to the mounting portion85. Accordingly, rotation of the ejection piece83with respect to the rod member82is restricted.

In the vicinity of a tip end portion of the rod member82, a fixing pin89is attached in a state where the fixing pin89slightly protrudes toward outside of the mounting portion85, and a downward movement of the ejection piece83is restricted by the fixing pin89.

The biasing member84is formed of, for example, a coil spring or the like, is mounted above the ejection piece83of the mounting portion85, and biases (presses) the ejection piece83toward a tip end (lower) side of the ejection rod81. As described above, in the ejection piece83, the tip end surface87aof the abutment portion87abuts against the bottom surface11aof the neck portion11. At this time, a biasing force of the biasing member84is transmitted, via the ejection piece83, to the container10. That is, when the ejection piece83is inserted into the container10, the container10is biased downward by the biasing force of the biasing member84.

A method for taking out the container10in the take-out part80including such an ejection rod81will be described with reference toFIG.8.

When the container10is conveyed from the blow molding part70to the take-out part80in a state where the neck portion11of the container10is held by the neck mold52, the ejection rod81is lowered and inserted into the container10as shown in (a) ofFIG.8. Specifically, the ejection rod81is lowered, so that the engagement portion86of the ejection piece83is loosely fitted into the small-diameter portion14of the container10or abuts against (engages with) an inner surface of the small-diameter portion14.

At this time, at a time point when the tip end surface87aof the abutment portion87abuts against the bottom surface11aof the neck portion11, lowering of the ejection piece83is stopped, but lowering of the rod member82is continued. As shown in (b) ofFIG.8, at a time point when the tip end portion of the rod member82reaches a predetermined position, the lowering of the rod member82is stopped. That is, the lowering of the rod member82is stopped at a position where the biasing force of the biasing member84on the ejection piece83and the container10becomes a desired magnitude.

When the rod member82is further lowered in a state where the ejection piece83abuts against the bottom surface11aof the neck portion11, the ejection piece83moves relatively to an upper side of the rod member82. With such a movement, the biasing member84that is the coil spring contracts. As a result, the biasing force on the ejection piece83and the container10is increased.

Then, in a state where the container10is biased by the biasing member84in this way, the ejection rod81is rotated. At this time, the engagement portion86of the ejection piece83engages with an inner peripheral surface of the small-diameter portion14, and the container10is also rotated together. That is, the container10is rotated along the inner screw portion16of the neck portion11. Accordingly, the container10moves downward from the neck mold52and is finally demolded from the neck mold52.

The container10is demolded from the neck mold52by such a method, whereby the container10can be successfully demolded from the neck mold52while preventing deformation of the inner screw portion16. That is, when molding the container10which includes the inner screw portion16serving as an undercut, the container10can be successfully demolded from the neck mold (inner neck mold)52while preventing the deformation of the inner screw portion16.

Particularly, in the present embodiment, since the container10is rotated while being biased downward, the container10can be more successfully demolded from the neck mold52. It goes without saying that even when the container10is rotated in a state where the container10is not biased downward, the container10can be demolded from the neck mold52.

Although not shown in the drawings, the ejection rod81is preferably configured, for example, such that an endless belt is extended between a motor and the ejection rod via a plurality of pulleys, and to rotate using the motor as a driving source.

In order to demold the container10from the neck mold52, it is necessary to rotate the ejection rod81several times. By using the endless belt, the ejection rod81can be relatively easily rotated. Further, when a plurality of containers10are molded at a time, a plurality of ejection rods81can be simultaneously rotated by the endless belt.

It goes without saying that the method for rotating the ejection rod81is not particularly limited. For example, the ejection rod81may be rotated by a power transmission mechanism using a rack, a pinion, or the like. However, in order to rotate the ejection rod81a plurality of times, there are fears that a size of an apparatus will increase, for example, the rack will become long.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the embodiment described above. The present invention may be appropriately modified without departing from the scope of the invention.

In the embodiment described above, the opening shape of the neck portion11of the container10is octagonal, but an opening shape of the small-diameter portion14is not limited thereto. For example, as shown inFIG.9, convex portions19that protrude inwardly may be provided on an inner peripheral surface of the small-diameter portion14. That is, the small-diameter portion14may have a circular shape including the convex portions19. In the present embodiment, four convex portions19are provided on an inner surface of the small-diameter portion14at intervals of 90 degrees. Further, the convex portions19are continuously provided along a depth direction of the small-diameter portion14. Only the opening shape (cross-sectional shape of an inner diameter of the small-diameter portion14) in the vicinity of an upper end (in the vicinity of the bottom surface11a) of the small-diameter portion14may be formed in a polygonal shape. Further, the convex portions19may be provided only in the vicinity of the upper end of the small-diameter portion14(in the vicinity of the bottom surface11a).

On the other hand, as in the embodiment described above, the engagement portion86of the ejection piece83that loosely fits or engages with such small-diameter portion14may have a cross-sectional shape substantially the same as the opening shape of the small-diameter portion14. Further, for example, as shown inFIG.10, an engagement portion86A may engage with the convex portions19when the ejection rod81is rotated to one side.

Specifically, the engagement portion86A includes a plurality of claw portions86athat engage with the convex portions19on an outer peripheral portion thereof. These claw portions86aare inclined at a predetermined angle with respect to a radial direction of the ejection piece83. Accordingly, when the ejection rod81is rotated to one side, the claw portions86aof the engagement portion86engage with the convex portions19of the small-diameter portion14. Therefore, the container10is rotated together with the ejection rod81.

When the ejection rod81rotates to the other side, although the claw portions86aof the engagement portion86abut against the convex portions19, the claw portions86amove over without being engaged with the convex portions19. Therefore, the container10is not rotated with the ejection rod81, and only the ejection rod81is rotated.

With such a configuration, the container10can be more appropriately rotated by the ejection rod81and demolded from the neck mold52.

For example, in the embodiment described above, when the container10is demolded from the neck mold52, the abutment portion87of the ejection piece83abuts against the neck portion11of the container10and biases the container10downward. However, a position where the ejection piece83abuts is not particularly limited. For example, a protrusion that protrudes inwardly may be provided in the vicinity of a lower end of the small-diameter portion14, and a tip end surface of the ejection piece83(engagement portion86) may abut against the protrusion.

In the embodiment described above, although the configuration is exemplified in which the small-diameter portion14of the container10is formed with an outer diameter smaller than that of the neck portion11, a size of the outer diameter of the neck portion11is not particularly limited. For example, as shown inFIG.11, the small-diameter portion14of a container10A may have an outer diameter substantially the same as that of the neck portion11. Although not shown in the drawings, in this case, the connection portion20aof the preform20also has an outer diameter substantially the same as that of the neck portion21.

A length of the small-diameter portion14(length in a vertical direction in the drawing) is also not particularly limited as long as the ejection rod81can be engaged. For example, the length of the small-diameter portion14of the container10A shown inFIG.11is shorter than that of the container10shown inFIG.1.

In the embodiment described above, although the configuration is exemplified in which the injection molding mold51includes the neck mold52that is the inner neck, the configuration of the injection molding mold51is not limited thereto. For example, as shown inFIG.12, an injection molding mold51A may include a neck mold52A including an outer neck mold57and an inner neck mold58, and include an injection cavity mold53A that forms the body portion22of the preform20. That is, instead of the injection cavity mold53, an outer surface of the neck portion21may be formed by the outer neck mold57that constitutes the neck mold52A.

In this case, the preform20formed in the injection molding part50is conveyed to the temperature adjustment part60and the blow molding part70in a state where the neck portion21is held by the outer neck mold57and the inner neck mold58that constitute the neck mold52A. Further, the container10blow-molded by the blow molding part70is also conveyed to the take-out part80in a state where the neck portion11is held by the outer neck mold57and the inner neck mold58.

In the take-out part80, as shown inFIG.13, the ejection rod81is rotated as described above in a state where the neck portion11is held by the outer neck mold57and the inner neck mold58. Accordingly, the container10moves downward from the inner neck mold58and is finally demolded from the inner neck mold58. Further, with such a rotation operation, the container10is simultaneously demolded from the outer neck mold57.

The outer neck mold57may include a plurality of split molds (for example, a pair of split molds) or the like. In this case, the container10may be demolded from the outer neck mold57at a timing different from a timing when the container10is demolded from the inner neck mold58, for example, before the ejection rod81is rotated in the take-out part80. That is, the outer neck mold57including the pair of split molds may be opened before the ejection rod81is rotated, and the neck portion11of the container10may be demolded from the outer neck mold57earlier than from the inner neck mold58.

Further, for example, in the embodiment described above, although the configuration in which one container is molded is exemplified as the injection blow molding apparatus, it goes without saying that the injection blow molding apparatus may be configured to mold a plurality of containers at a time. Further, in the embodiment described above, although the configuration in which the injection blow molding apparatus includes the temperature adjustment part is exemplified, the injection blow molding apparatus may include the temperature adjustment part as necessary, and may not necessarily include the temperature adjustment part.

In the embodiment described above, although the container is demolded from the neck mold in the take-out part, it goes without saying that the container may be demolded from the neck mold in the blow molding part. That is, the blow molding part may also serve as the take-out part.

In the embodiment described above, although the container is exemplified as an example of the hollow article, the present invention can be applied to various hollow articles and molding thereof. For example, the hollow article may be a preform for blow molding a container that is a final product. That is, the present invention can also be applied to demolding the preform from an injection molding mold.

REFERENCE SIGNS LIST