Patent Description:
Synthetic resin containers, representatives of which are polypropylene (PP) bottles and polyethylene terephthalate (PET) bottles, are used in applications in which a variety of liquids such as beverages and toiletries including cosmetics, chemicals, detergents, shampoos or the like are contained as a content liquid. Such containers are generally manufactured by blow molding a preform formed by a thermoplastic synthetic resin material described above.

As the blow molding in which a preform is molded into a container, liquid blow molding is known, in which, as a pressurized medium supplied into a preform, a pressurized liquid is used instead of pressurized air.

For example, Patent Literature <NUM> (PTL <NUM>) discloses a liquid blow molding method in which a synthetic resin preform heated in advance to a temperature at which stretchability is achieved is placed into a mold for blow molding and a liquid pressurized to a predetermined pressure by a pressure pump is supplied into the preform through a blow nozzle. In this manner the preform is molded into a container of a predetermined shape conforming to a cavity of the mold for blow molding.

In the above described liquid blow molding method, as a liquid supplied into a preform, a content liquid such as beverages or cosmetics contained finally in a container as a product is used, and molding of a container and filling of a content liquid are performed at the same time. In this manner a liquid container containing a content liquid can be manufactured. Therefore, according to the method for manufacturing a liquid container using the liquid blow molding described above, a step of filling a content liquid into a container after molding is omitted, and a liquid container can be manufactured at a low cost.

The disclosures of the following documents may be helpful for understanding the present invention. <CIT> discloses method and system for hydraulic blow molding a container from a preform. A molding medium is injected into the preform from a nozzle during a first molding stage. In the first molding stage, the molding medium is injected so as to be specifically directed at a closed end of the preform. During the first molding stage, the preform is axially stretched in response to the force exerted on the preform by the molding medium. The molding medium is also injected into the preform during a second molding stage, where the molding medium is injected at a flow rate greater than a flow rate during the first molding stage. During the second molding stage, the preform is radially expanded into the shape of the container. <CIT> discloses a liquid blow molding apparatus with a mold in which a preform is arranged and a nozzle unit that has a supply port through which a liquid can be supplied from above into the preform arranged in the mold. The nozzle unit is provided with a seal body that is movable among a closed position where supplying of the liquid through the supply port is blocked, a first open position where supplying of the liquid through only a part, in the circumferential direction, of the supply port is permitted, and a second open position where supplying of the liquid through the entire part, in the circumferential direction, of the supply port is permitted. <CIT> discloses a liquid-containing container that contains a liquid content and that is molded from a bottomed cylindrical preform by supplying a first liquid into the preform, which has been heated to a predetermined temperature, at a predetermined pressure through a first supply channel, thereby liquid blow molding the preform. A second liquid is supplied into the preform through a second supply channel that is different from the first supply channel after the supply of the first liquid or along with the supply of the first liquid.

However, in the above described existing liquid blow molding method, a liquid as a pressurized medium is supplied into a preform while entraining the air present in the preform, thus foaming of the liquid may cause a decline of stability of the molding conditions and of moldability of a container, or the like.

The present disclosure has been conceived in view of the above described problem, and is to provide an apparatus and a method for manufacturing a liquid container in which a liquid container having a predetermined content volume and a shape can be manufactured precisely at a low cost.

The present invention refers to an apparatus for manufacturing a liquid container according to claim <NUM> and a method for manufacturing a liquid container according to claim <NUM>. Advantageous embodiments may include features of depending claims. Thus an apparatus for manufacturing a liquid container according to the present invention includes a mold for blow molding and a nozzle unit and manufactures a liquid container containing a content liquid from a synthetic resin preform. The nozzle unit includes a nozzle unit body in which a liquid supply path is provided and a seal body disposed in the supply path. The seal body has an annular first seal portion, an annular second seal portion and a spare supply path extending from a liquid flow inlet located between the first seal portion and the second seal portion to a liquid flow outlet located closer to a tip side of the seal body than the second seal portion. The seal body can move, relative to the nozzle unit body, between a blocked position where the first seal portion sits on the supply path, a spare supply position where the first seal portion separates from the supply path and the second seal portion sits on the supply path and an open position where the first seal portion separates from the supply path and the second seal portion separates from the supply path. Further the nozzle unit has a stretching rod configured to stretch the preform in an axial direction and the spare supply path has a longitudinal flow path through which the stretching rod passes. A passage of the stretching rod serves also as the longitudinal flow path of the spare supply path in the seal body.

In the disclosed apparatus for manufacturing a liquid container configured in the above described manner, it is preferable that the seal body has a seal main body and a tip member attachable to and detachable from the seal main body, and the spare supply path is provided to the tip member.

In the disclosed apparatus for manufacturing a liquid container configured in the above described manner, it is preferable that the spare supply path has a lateral flow path extending from the flow inlet to the longitudinal flow path, and that the stretching rod can move, in the retracting direction, to a position beyond a connecting point between the lateral flow path and the longitudinal flow path.

In the disclosed apparatus for manufacturing a liquid container configured in the above described manner, it is preferable that the nozzle unit has a blow nozzle that has an inner peripheral surface forming a lower end of the supply path and is configured to engage with a mouth of the preform, and that the inner peripheral surface of the blow nozzle is provided with an exhaust port configured to exhaust air out of the preform.

The method for manufacturing a liquid container according to the present invention is a method for manufacturing a liquid container by using the above described apparatus for manufacturing a liquid container. The method includes: an air exhaust step of exhausting air out of the preform by moving the seal body from the blocked position to the spare supply position to supply a liquid from the supply path into the preform placed in the mold for blow molding through the spare supply path; and a liquid blow molding step of molding the preform into a liquid container of a shape conforming to an inner surface of the mold for blow molding by moving the seal body from the spare supply position to the open position to supply a pressurized liquid from the supply path into the preform.

In the disclosed method for manufacturing a liquid container configured in the above described manner, it is preferable that the method further includes a rod stretching step of stretching the preform by the stretching rod in the axial direction before or during the liquid blow molding step.

In the disclosed method for manufacturing a liquid container configured in the above described manner, it is preferable that the nozzle unit has a blow nozzle that has an inner peripheral surface forming a lower end of the supply path and is configured to engage with a mouth of the preform, and that, in the air exhaust step, a liquid is supplied from the supply path into the preform placed in the mold for blow molding through the spare supply path by moving the seal body from the blocked position to the spare supply position with the blow nozzle of the nozzle unit engaged with the mouth of the preform to exhaust air out of the preform through an exhaust port provided in the inner peripheral surface of the blow nozzle.

According to the present disclosure, an apparatus and a method for manufacturing a liquid container having a predetermined content volume and a shape can be manufactured precisely at a low cost can be provided.

The present disclosure will be described in more detail below with reference to drawings.

First, an apparatus <NUM> for manufacturing a liquid container according to an embodiment of the present disclosure will be illustrated with reference to <FIG>.

The apparatus <NUM> for manufacturing a liquid container illustrated in <FIG> manufactures a liquid container C containing a content liquid (see <FIG>) from a synthetic resin preform <NUM>. As a liquid (content liquid) L contained in a liquid container C, a variety of liquids L such as, for example, beverages and toiletries including cosmetic products, pharmaceutical products, detergents and shampoo can be adopted.

As the preform <NUM>, those formed, by a thermoplastic synthetic resin material such as polypropylene (PP) and polyethylene terephthalate (PET), for example, into a bottomed tubular shape including a cylindrical mouth 2a, which is an open end, and a cylindrical body 2b continuing to the mouth 2a and including a closed lower end can be used.

Although not illustrated in detail, on the outer wall surface of the mouth 2a is provided with an engaging protrusion used to mount a blocking cap (not illustrated) to the mouth 2a of the liquid container C after molding through plugging (undercut engagement). It is to be noted that, instead of the engaging protrusion, a male thread may be provided to the outer wall surface of the mouth 2a so as to mount the blocking cap to the mouth 2a through thread connection.

As illustrated in <FIG>, the apparatus <NUM> for manufacturing a liquid container has a mold for blow molding <NUM>. The mold for blow molding <NUM> has a cavity <NUM> of a shape corresponding to a final shape of a liquid container C such as a bottle shape, for example. The cavity <NUM> opens upward in the upper surface of the mold for blow molding <NUM>. The preform <NUM> is placed in the mold for blow molding <NUM> with the body 2b disposed in the cavity <NUM> of the mold for blow molding <NUM> and with the mouth 2a protruded upward from the mold for blow molding <NUM>.

The mold for blow molding <NUM> can be opened right and left. After the preform <NUM> is molded into a liquid container C, the liquid container C can be ejected from the mold for blow molding <NUM> by opening the mold for blow molding <NUM> right and left.

Above the mold for blow molding <NUM> is provided with a nozzle unit <NUM> configured to supply a pressurized liquid L into the preform <NUM>. The nozzle unit <NUM> has a main body block <NUM>.

As illustrated in <FIG>, the lower end of the main body block <NUM> is provided with a support block <NUM>, and a blow nozzle <NUM> is mounted to the lower end of the main body block <NUM> by being supported by the support block <NUM>. The blow nozzle <NUM> is formed into a substantially cylindrical shape. The nozzle unit body 20a includes the main body block <NUM>, the support block <NUM> and the blow nozzle <NUM>. The nozzle unit body 20a is vertically movable relative to the mold for blow molding <NUM>. When the nozzle unit body 20a is lowered to the stroke end on the lower side, the nozzle unit body 20a (in particular, the blow nozzle <NUM>) engages, in a sealed manner, with the mouth 2a of the preform <NUM> placed in the mold for blow molding <NUM> from above.

A supply path <NUM> extending in the vertical direction is provided in the nozzle unit body 20a (in particular, the main body block <NUM> and the blow nozzle <NUM>). The lower end of the supply path <NUM> includes a nozzle inner peripheral surface 23c of the blow nozzle <NUM>. The nozzle unit body 20a (in particular, the main body block <NUM>) is provided with a supply port <NUM> communicating with the upper end of the supply path <NUM>.

As illustrated in <FIG>, in this embodiment, the supply path <NUM> has an annular (toric) first seat 24a and an annular (toric) second seat 24b located downstream of the first seat 24a. The first seat 24a and the second seat 24b are formed by the blow nozzle <NUM>. The blow nozzle <NUM> has a large inner diameter portion 23a and a small inner diameter portion 23b adjacent to the downstream side (lower side) of the large inner diameter portion 23a and having an inner diameter smaller than that of the large inner diameter portion 23a. The large inner diameter portion 23a has a large inner diameter portion upper surface 23c formed from an upper surface sloping downward in a conical manner and a large diameter inner peripheral surface 23d formed from an inner peripheral surface hanging down in parallel with an axial center of a seal body <NUM> from an inner peripheral edge of the large inner diameter portion upper surface 23c. The small inner diameter portion 23b has a small inner diameter portion upper surface 23e formed from an annular horizontal (possibly inclined) upper surface and a small diameter inner peripheral surface 23f formed from an inner peripheral surface hanging down in parallel with the axial center of the seal body <NUM> from the inner peripheral edge of the small inner diameter portion upper surface 23e. In this embodiment, the first seat 24a is formed from the large inner diameter portion upper surface 23c and the second seat 24b is formed from the large diameter inner peripheral surface 23d. The small diameter inner peripheral surface 23f forms the lower end of the supply path <NUM>. The shapes of the large inner diameter portion upper surface 23c, the large diameter inner peripheral surface 23d, the small inner diameter portion upper surface 23e and the small diameter inner peripheral surface 23f can be changed.

The seal body <NUM> is disposed in the supply path <NUM>. The seal body <NUM> has an annular (toric) first seal portion <NUM> and an annular (toric) second seal portion <NUM>. The seal body <NUM> has a spare supply path <NUM> extending from a liquid flow inlet <NUM> located between the first seal portion <NUM> and the second seal portion <NUM> to a liquid flow outlet <NUM> located closer to a tip side of the seal body <NUM> than the second seal portion <NUM>. In this embodiment, the seal body <NUM> has a large outer diameter portion 26a, a medium outer diameter portion 26b adjacent to the downstream side (lower side) of the large outer diameter portion 26a and having an outer diameter smaller than that of the large outer diameter portion 26a and a small outer diameter portion 26c adjacent to the downstream side (lower side) of the medium outer diameter portion 26b and having an outer diameter smaller than that of the medium outer diameter portion 26b. The large outer diameter portion 26a has a large diameter outer peripheral surface 26d formed from an outer peripheral surface in parallel with the axial center of the seal body <NUM> and a large outer diameter portion lower surface 26e formed from a lower surface sloping downward in a conical manner. The large outer diameter portion lower surface 26e has an inclination that coincides with the large inner diameter portion upper surface 23c of the blow nozzle <NUM>. In this embodiment, the first seal portion <NUM> is formed from the large outer diameter portion lower surface 26e that can sit on the first seat 24a (in a liquid-tight manner). The medium outer diameter portion 26b has a medium diameter outer peripheral surface 26f formed from an outer peripheral surface in parallel with the axial center of the seal body <NUM> and a medium outer diameter portion lower surface <NUM> formed from an annular horizontal (or inclined) lower surface. The second seal portion <NUM> is formed from (the lower end) of the medium diameter outer peripheral surface 26f that can sit on the second seat 24b (in a liquid-tight manner). The flow inlet <NUM> is provided (above the second seal portion <NUM>) in the medium diameter outer peripheral surface 26f. The small outer diameter portion 26c has a small diameter outer peripheral surface <NUM> formed from an outer peripheral surface in parallel with the axial center of the seal body <NUM> and a small outer diameter portion lower surface 26i formed from an annular horizontal (or inclined) lower surface. The flow outlet <NUM> is provided in (the center of) the small outer diameter portion lower surface 26i. The shapes of the large outer diameter portion 26a, the medium outer diameter portion 26b, the small outer diameter portion 26c, the large diameter outer peripheral surface 26d, the large outer diameter portion lower surface 26e, the medium diameter outer peripheral surface 26f, the medium outer diameter portion lower surface <NUM>, the small diameter outer peripheral surface <NUM> and the small outer diameter portion lower surface 26i can be changed.

The seal body <NUM> can move relative to the nozzle unit body 20a between the blocked position (see <FIG>) where the first seal portion <NUM> sits on the first seat 24a of the supply path <NUM> (in a liquid-tight manner), a spare supply position (see <FIG> and <FIG>) where the first seal portion <NUM> separates from the first seat 24a of the supply path <NUM> and the second seal portion <NUM> sits on the second seat 24b of the supply path <NUM> (in a liquid-tight manner), and an open position (see <FIG>) where the first seal portion <NUM> separates from the first seat 24a of the supply path <NUM> and the second seal portion <NUM> separates from the second seat 24b of the supply path <NUM>. The supply path <NUM> is blocked at the blocked position. The supply path <NUM> is opened only through the spare supply path <NUM> at the spare supply position. The supply path <NUM> is opened through a gap formed between the seal body <NUM> and the supply path <NUM> at the open position. In this embodiment, the supply path <NUM> is opened only through the gap at the open position. It is to be noted that, at the open position, the supply path <NUM> may be opened through both the gap and the spare supply path <NUM>. As illustrated in <FIG>, the seal body <NUM> is fixed to a shaft body <NUM> provided movable in the vertical direction relative to the nozzle unit body 20a, and can move in the vertical direction in the supply path <NUM>. It is to be noted that the seal body <NUM> may be formed integrally with the shaft body <NUM>.

The arrangement and the shape of the first seal portion <NUM> and/or the second seal portion <NUM> can be changed. For example, the first seal portion <NUM> may be formed from (the upper end of) the medium diameter outer peripheral surface 26f (see <FIG>). In this case, both the first seat 24a and the second seat 24b are formed from the large diameter inner peripheral surface 23d (that is, the second seat 24b serves as the first seat 24a). The second seal portion <NUM> may be formed from the small diameter outer peripheral surface <NUM>. In this case, the second seat 24b is formed from the small diameter inner peripheral surface 23f. Further, in this case, the seal body <NUM> may not be provided with the medium outer diameter portion 26b (the flow inlet <NUM> is formed above the second seal portion <NUM> in the small diameter outer peripheral surface <NUM>). In this embodiment, the medium outer diameter portion lower surface <NUM> and the small inner diameter portion upper surface 23e may be configured to abut to each other or not to abut to each other with the seal body <NUM> located at the blocked position. When they are configured to abut to each other, it is preferable that the shape of the medium outer diameter portion lower surface <NUM> may be the same as that of the small inner diameter portion upper surface 23e. In this embodiment, the small diameter outer peripheral surface <NUM> and the small diameter inner peripheral surface 23f may be configured to abut to each other or not to abut to each other with the seal body <NUM> located at the blocked position. When they are configured to abut to each other, it is preferable that the small diameter outer peripheral surface <NUM> has the same shape as that of the small diameter inner peripheral surface 23f at the abutted portion. The seal body <NUM> may not be provided with the small outer diameter portion 26c.

As illustrated in <FIG>, the seal body <NUM> has a seal main body <NUM> and a tip member <NUM> that is attachable to and detachable from the seal main body <NUM>, and the spare supply path <NUM> is provided to the tip member <NUM>. The medium diameter outer peripheral surface 26f, the medium outer diameter portion lower surface <NUM>, the small diameter outer peripheral surface <NUM> and the small outer diameter portion lower surface 26i of the seal body <NUM> are provided to the tip member <NUM>. The large outer diameter portion lower surface 26e of the seal body <NUM> is provided to the seal main body <NUM>. The tip member <NUM> has a screw portion 34a screwed onto the seal main body <NUM>. Instead of the screw portion 34a, the tip member <NUM> may have, as an engaging portion that allows the tip member <NUM> to be attachable to and detachable from the seal main body <NUM>, a fitting portion, for example. A seal ring <NUM> configured to seal between the stretching rod <NUM> and the seal body <NUM> is disposed between the seal main body <NUM> and the tip member <NUM>.

As illustrated in <FIG>, the nozzle unit <NUM> has the stretching rod <NUM> configured to stretch the preform <NUM> in the axial direction. The stretching rod <NUM> formed into a substantially columnar shape by steel and the like is inserted into the axial center of the shaft body <NUM>, passes through the axial center of the seal main body <NUM> and extends through the longitudinal flow path 31a of the spare supply path <NUM>. The stretching rod <NUM> is driven by a driving source not illustrated and can move in the vertical direction relative to the shaft body <NUM> and the seal body <NUM>. The stretching rod <NUM> moves downward through the longitudinal flow path 31a and protrudes from the lower end of the seal body <NUM> such that the preform <NUM> can be stretched in the axial direction. However, the nozzle unit <NUM> may not have the stretching rod <NUM>.

As illustrated in <FIG>, the spare supply path <NUM> includes the longitudinal flow path 31a extending downward to the flow outlet <NUM> and a plurality of lateral flow paths 31b horizontally extending from the flow inlet <NUM> to the longitudinal flow path 31a in the radial direction. The lateral flow paths 31b may extend obliquely (preferably obliquely downward) from the flow inlet <NUM> to the longitudinal flow path 31a. The lateral flow paths 31b are disposed at equal angular intervals in the circumferential direction, for example. The number of the lateral flow paths 31b may not be limited to two or more, and may be one. The stretching rod <NUM> can move to a position beyond the connecting portion between the lateral flow path 31b and the longitudinal flow path 31a in the retracting direction (upward) (see <FIG> and <FIG>). In this embodiment, the stretching rod <NUM> moves to the position beyond the connecting portion between the lateral flow path 31b and the longitudinal flow path 31a in the retracting direction before, during or after the seal body <NUM> moves from the blocked position to the spare supply position. In this manner the longitudinal flow path 31a is opened and a liquid L is supplied from the longitudinal flow path 31a into the preform <NUM>. However, it is also possible to provide a gap (e.g. an annular gap), between the stretching rod <NUM> and the longitudinal flow path 31a, through which the liquid L can pass, and the liquid L may be supplied into the preform <NUM> through the gap while the stretching rod <NUM> passes through the longitudinal flow path 31a. The shape of the spare supply path <NUM> is not limited to that having the longitudinal flow path 31a and the lateral flow path 31b, and may be changed.

As illustrated in <FIG>, the small diameter inner peripheral surface 23f forming the inner peripheral surface of the blow nozzle <NUM> is provided with an exhaust port <NUM> configured to exhaust air out of the preform <NUM>. A tip recess <NUM> formed from a recess extending from the tip portion of the seal body <NUM> to the base end side and provided continuously or intermittently in the circumferential direction is formed in the small diameter outer peripheral surface <NUM> of the seal body <NUM>. Inside (the nozzle unit body 20a of) the nozzle unit <NUM> is provided with an exhaust flow path <NUM> configured to communicate the exhaust port <NUM> with the outside. The exhaust flow path <NUM> is provided with an opening-closing valve for exhaust V2. It is preferable that the opening-closing valve for exhaust V2 is a solenoid valve, and the air in the preform <NUM> can be exhausted to the outside through the tip recess <NUM>, the exhaust port <NUM> and the exhaust flow path <NUM> by opening the opening-closing valve for exhaust V2. However, the nozzle unit <NUM> may not have the exhaust port <NUM>.

As illustrated in <FIG>, a pressurized liquid supply source <NUM> is connected to the supply port <NUM> through a pipe P1. The pressurized liquid supply source <NUM> may be a plunger pump that includes a cylinder 40a and a piston (plunger) 40b, for example.

A supply tank <NUM> is connected to the pressurized liquid supply source <NUM>. The supply tank <NUM> can store a liquid L, heat the liquid L up to a predetermined temperature and keep the liquid L at the temperature. An opening-closing valve V1 is provided to a flow path between the pressurized liquid supply source <NUM> and the supply tank <NUM>, and the flow path can be opened and closed by the opening-closing valve V1. It is to be noted that the reference sign <NUM> represents a pressure gauge provided to the pipe P1.

As illustrated in <FIG>, the pressurized liquid supply source <NUM> can supply the liquid L pressurized to a predetermined pressure into the preform <NUM> through the pipe P1, the supply port <NUM> and (the small diameter inner peripheral surface 23f of) the supply path <NUM> by being operated in a positive direction (pressurized direction) in a state where the nozzle unit <NUM> (in particular the blow nozzle <NUM>) is engaged with the mouth 2a of the preform <NUM> placed in the mold for blow molding <NUM> in a sealed manner and the seal body <NUM> is at an open position. The pressurized liquid supply source <NUM> may not be operated in the positive direction (pressurized direction) when the seal body <NUM> is at the spare supply position as illustrated in <FIG>. In this case, a liquid L is supplied from the spare supply path <NUM> into the preform <NUM> only by gravity. The pressurized liquid supply source <NUM> may be operated in the positive direction (pressurized direction) in a state where the seal body <NUM> is at the spare supply position. In this case, a pressurized liquid L can be supplied into the preform <NUM> via the pipe P1, the supply port <NUM>, the supply path <NUM> and the spare supply path <NUM>. The pressure of the liquid L in this case may be smaller than the predetermined pressure described above.

The pressurized liquid supply source <NUM> operates in a reverse direction with the seal body <NUM> positioned at the blocked position and the opening-closing valve V1 open. In this manner, the liquid L stored in the supply tank <NUM> is sucked into the cylinder 40a to prepare for the next liquid blow molding.

Operation of the nozzle unit <NUM>, the seal body <NUM>, the stretching rod <NUM>, the pressurized liquid supply source <NUM>, the opening-closing valve V1, the opening-closing valve for exhaust V2 and the like are controlled by a controller (not illustrated) in an integrated manner. This control can be performed with reference to the values and the like of the pressure gauge <NUM>. It is preferable that the opening-closing valve V1 may be provided as a solenoid valve that can be controlled by a controller.

Next, a method for manufacturing a liquid container according to an embodiment of the present disclosure will be illustrated.

The method for manufacturing a liquid container according to an embodiment of the present disclosure is a method for manufacturing a liquid container by using the apparatus <NUM> for manufacturing a liquid container according to the above described embodiment. The method includes: an air exhaust step of exhausting air out of the preform <NUM> by moving the seal body <NUM> from the blocked position to the spare supply position to supply a liquid L from the supply path <NUM> into the preform <NUM> placed in the mold for blow molding <NUM> through the spare supply path <NUM><NUM>; and a liquid blow molding step of molding the preform <NUM> into a liquid container C of a shape conforming to an inner surface of the mold for blow molding <NUM> by moving the seal body <NUM> from the spare supply position to the open position to supply a pressurized liquid L from the supply path <NUM> into the preform <NUM>.

In the method for manufacturing a liquid container according to this embodiment, the nozzle unit <NUM> has a stretching rod <NUM> configured to stretch the preform <NUM> in the axial direction, and the method further includes a rod stretching step of stretching the preform <NUM> in the axial direction by the stretching rod <NUM> before or during the liquid blow molding step.

In the method for manufacturing a liquid container according to this embodiment, the nozzle unit <NUM> has a blow nozzle <NUM> that has an inner peripheral surface (small diameter inner peripheral surface 23f) forming a lower end of the supply path <NUM> and is configured to engage with the mouth 2a of the preform <NUM>, and in the air exhaust step, a liquid L is supplied from the supply path <NUM> into the preform <NUM> placed in the mold for blow molding <NUM> through the spare supply path <NUM> by moving the seal body <NUM> from the blocked position to the spare supply position with the blow nozzle <NUM> of the nozzle unit <NUM> engaged with the mouth 2a of the preform <NUM> to exhaust air out of the preform <NUM> through an exhaust port <NUM> provided in the inner peripheral surface of the blow nozzle <NUM>.

However, the method for manufacturing a liquid container according to this embodiment may be performed by using an apparatus that is different from the apparatus <NUM> for manufacturing a liquid container according to this embodiment described above.

In the method for manufacturing a liquid container according to this embodiment, as illustrated in <FIG>, first, the preform <NUM> is placed in the mold for blow molding <NUM> and is clamped, the preform <NUM> having been preheated to a predetermined temperature (e.g. from <NUM> to <NUM>) at which stretchability is achieved by using a heating means (not illustrated) such as a heater.

At this time, the nozzle unit <NUM> is located above the mold for blow molding <NUM> separated from the mold and the seal body <NUM> is located at the blocked position. Further, since the mouth 2a of the preform <NUM> is opened, inside the preform <NUM> is filled with the air.

Next the air exhaust step is performed. In the air exhaust step, first, the nozzle unit <NUM> is lowered to the position where the mouth 2a of the preform <NUM> is engaged with (the blow nozzle <NUM> of) the nozzle unit <NUM>, and the opening-closing valve for exhaust V2 is opened. Next, as illustrated in <FIG>, the seal body <NUM> is raised and moved from the blocked position to the spare supply position such that the spare supply path <NUM> is opened, and the liquid L is supplied from the spare supply path <NUM> into the preform <NUM> such that the air is exhausted out of the preform <NUM> through the exhaust port <NUM>. That is, when the liquid L is supplied into the preform <NUM>, most of the air filled in the preform <NUM> is pushed out by the liquid L and is exhausted. At this time, the liquid L is supplied with conditions (pressure and the like) under which the preform <NUM> is not substantially stretched (expanded). Exhaust of air is finished by closing the opening-closing valve for exhaust V2.

When the air exhaust step is finished, the liquid blow molding step is performed. In the liquid blow molding step, first, as illustrated in <FIG>, the seal body <NUM> is raised and moved from the spare supply position to the open position. In this state the pressurized liquid supply source <NUM> is operated in the positive direction and a liquid L pressurized at a predetermined pressure is supplied into the preform <NUM> through the small diameter inner peripheral surface 23f. In this manner, a pressurized liquid L is supplied into the preform <NUM>, and by the pressure of the liquid L, the preform <NUM> is molded into a liquid container C of a predetermined shape conforming to an inner surface of the cavity <NUM> of the mold for blow molding <NUM> (see <FIG>).

In this context, since the liquid blow molding step is performed after most of the air in the preform <NUM> is exhausted to the outside in the air exhaust step, when a pressurized liquid L is supplied into the preform <NUM>, the liquid L does not catch the air. In this manner, mixing of air into the liquid L in the liquid container C is prevented. Further, in the air exhaust step, a liquid L is supplied into the preform <NUM> only through the spare supply path <NUM> formed inside the seal body <NUM>, not through the small diameter inner peripheral surface 23f. The circumferential length (of the longitudinal flow path 31a) of the spare supply path <NUM> when the liquid L is supplied from the spare supply path <NUM> can be shorter than the circumferential length of all over the open portion inside the small diameter inner peripheral surface 23f when the liquid L is supplied through the small diameter inner peripheral surface 23f. Further, the diameter dimension (of the longitudinal flow path 31a) of the spare supply path <NUM> when the liquid L is supplied from the spare supply path <NUM> can be smaller than that of all over the open portion inside the small diameter inner peripheral surface 23f when the liquid L is supplied through the small diameter inner peripheral surface 23f. In this manner, a liquid L is prevented from being biased in the circumferential direction when flowing in the spare supply path <NUM>. Therefore, according to this embodiment, mixing of air from the open portion into the supply path <NUM> during supply of a liquid L in the air exhaust step can be prevented.

As with this embodiment, the rod stretching step can be performed during the liquid blow molding step. In the rod stretching step, the stretching rod <NUM> is moved forward in the downward direction such that the body 2b of the preform <NUM> is stretched by the stretching rod <NUM> in the axial direction (longitudinal direction). It is to be noted that the liquid blow molding step can be performed after the rod stretching step. A biaxial stretch blow molding in which a liquid blow molding is performed while the preform <NUM> is stretched by the stretching rod <NUM> in the axial direction can be performed by performing the liquid blow molding step after or during the rod stretching step (the rod stretching step may be started after the liquid blow molding step is started). In this manner the preform <NUM> can be molded into a liquid container C of a predetermined shape more precisely. It is preferable that the rod stretching step is performed after the air exhaust step. When the stretching rod <NUM> is moved forward before or during the air exhaust step, it is preferable that stretching of the preform <NUM> by the stretching rod <NUM> is started after the air exhaust step is finished. The liquid blow molding step may be performed without performing the rod stretching step.

After the liquid blow molding step, the seal body <NUM> is lowered and moved from the open position to the blocked position, and the nozzle unit <NUM> is moved upward relative to the mold for blow molding <NUM>. Thus (the blow nozzle <NUM> of) the nozzle unit <NUM> is separated from (the mouth 2a of) the liquid container C. After the liquid blow molding step, an additional step for forming a headspace in the liquid container C (e.g. a suck back step in which the pressurized liquid supply source <NUM> is operated in a reverse direction (sucking direction) by a predetermined operation amount while the seal body <NUM> is located at the open position to suck back a predetermined amount of liquid L from the inside of the liquid container C after molding into the supply path <NUM>) may be performed before the nozzle unit <NUM> is separated from the liquid container C. A finished liquid container C is ejected from the mold for blow molding <NUM> by opening the mold for blow molding <NUM>, and a blocking cap is attached to the mouth 2a thereof. In this manner the finished liquid container C is provided as a product. At this time, the pressurized liquid supply source <NUM> is operated in the reverse direction with the opening-closing valve V1 open, and the liquid L stored in the supply tank <NUM> is sucked into the cylinder 40a. It is to be noted that the liquid container C may be ejected from the mold for blow molding <NUM> by opening the mold for blow molding after a blocking cap is attached to the mouth 2a.

As described above, in the apparatus <NUM> for manufacturing a liquid container according to this embodiment, the liquid blow molding step can be performed after the air is exhausted out of the preform <NUM> in the air exhaust step. Thus when a pressurized liquid L is supplied into the preform <NUM> in the liquid blow molding step, mixing of air in the liquid L can be prevented. According to the apparatus <NUM> for manufacturing a liquid container of this embodiment, a liquid L can be supplied into the preform <NUM> through the spare supply path <NUM> in the air exhaust step, and thus mixing of air into the supply path <NUM> during supply of the liquid L can be prevented. Further, according to the apparatus <NUM> for manufacturing a liquid container of this embodiment, the air exhaust step can be performed with a simple operation in which the seal body <NUM> is moved from the blocked position to the spare supply position. Therefore, according to this embodiment, a decline in stability of molding conditions and moldability of a container due to foaming of liquid L in the preform and mixing of air into the supply path <NUM> during the liquid blow molding is prevented, and thus a liquid container C having a predetermined content volume and a shape can be manufactured precisely at a low cost.

Further, in the apparatus <NUM> for manufacturing a liquid container according to this embodiment, the spare supply path <NUM> is provided to the tip member <NUM>. Thus, a spare supply path <NUM> of a desired shape according to the molding conditions or the like can be provided to the seal body <NUM> by preparing a plurality of types of tip members <NUM> having a spare supply path <NUM> of a variety of shapes and changing the tip member <NUM> appropriately.

Further, in the apparatus <NUM> for manufacturing a liquid container according to this embodiment, since the passage of the stretching rod <NUM> serves also as (the longitudinal flow path 31a of) the spare supply path <NUM> in the seal body <NUM>, a configuration for performing the air exhaust step can be simplified, and the cost for it can be decreased.

Further, in the apparatus <NUM> for manufacturing a liquid container according to this embodiment, since the stretching rod <NUM> is moved to a position beyond the connecting portion between the lateral flow path 31b and the longitudinal flow path 31a in the retracting direction in the air exhaust step, the longitudinal flow path 31a can be opened completely. Thus, compared with the case where an annular gap is formed between the longitudinal flow path 31a and the stretching rod <NUM>, occurrence of biased flow of a liquid L in the circumferential direction in the spare supply path <NUM> can be further prevented. In this manner, according to this embodiment, mixing of air into the supply path <NUM> can be further prevented.

Further, in the apparatus <NUM> for manufacturing a liquid container according to this embodiment, since the blow nozzle <NUM> has the exhaust port <NUM>, the air exhaust step can be performed with the blow nozzle <NUM> engaged with the mouth 2a of the preform <NUM>. In this manner, according to this embodiment, possibility of a leakage of a liquid L in the air exhaust step can be reduced.

The present disclosure is not limited to the above described embodiment, and it is needless to say that various modifications may be made without departing from the scope of the claims.

For example, in the above described embodiment, the exhaust port <NUM> is provided to the blow nozzle <NUM>, and the air exhaust step is performed with the blow nozzle <NUM> engaged with the mouth 2a of the preform <NUM>, but it is not limited thereto. For example, the air exhaust step may be performed with the nozzle unit <NUM> lowered to the position immediately before the nozzle unit <NUM> is engaged with the preform <NUM> so as to secure a passage for exhausting air out of the preform <NUM>.

In the above described embodiment, the seal body <NUM> includes the seal main body <NUM> and the tip member <NUM> that is attachable to and detachable from the seal main body <NUM>, but is not limited thereto, and the seal main body <NUM> and the tip member <NUM> may be molded in an integral manner.

In the above described embodiment, the pressurized liquid supply source <NUM> is a plunger pump, but is not limited thereto, and a variety of types of pumps may be used as long as a liquid L can be pressurized to a predetermined pressure and supplied into the preform <NUM>.

Claim 1:
An apparatus (<NUM>) for manufacturing a liquid container (C) comprising a mold (<NUM>) for blow molding and a nozzle unit (<NUM>) and configured to manufacture a liquid container (C) containing a content liquid (L) from a synthetic resin preform (<NUM>), wherein,
the nozzle unit (<NUM>) has a nozzle unit body (20a) in which a liquid supply path (<NUM>) is provided and a seal body (<NUM>) disposed in the supply path (<NUM>);
the seal body (<NUM>) has an annular first seal portion (<NUM>), an annular second seal portion (<NUM>) and a spare supply path (<NUM>) extending from a liquid flow inlet (<NUM>) located between the first seal portion (<NUM>) and the second seal portion (<NUM>) to a liquid flow outlet (<NUM>) located closer to a tip side of the seal body (<NUM>) than the second seal portion (<NUM>);
the seal body (<NUM>) can move, relative to the nozzle unit body (20a), between a blocked position where the first seal portion (<NUM>) sits on the supply path (<NUM>), a spare supply position where the first seal portion (<NUM>) separates from the supply path (<NUM>) and the second seal portion (<NUM>) sits on the supply path (<NUM>) and an open position where the first seal portion (<NUM>) separates from the supply path (<NUM>) and the second seal portion (<NUM>) separates from the supply path (<NUM>),
wherein the nozzle unit (<NUM>) has a stretching rod (<NUM>) configured to stretch the preform (<NUM>) in an axial direction; and
wherein the spare supply path (<NUM>) has a longitudinal flow path (<NUM>1a) through which the stretching rod (<NUM>) passes,
characterized by that
a passage of the stretching rod (<NUM>) serves also as the longitudinal flow path (31a) of the spare supply path (<NUM>) in the seal body (<NUM>).