JP2019055513A - Method for manufacturing container containing liquid - Google Patents

Abstract

To provide a method for manufacturing a container containing a liquid which can accurately and inexpensively producing a container containing a liquid so as to have predetermined content and shape.SOLUTION: A method for manufacturing a container containing a liquid includes: a rod purge step of discharging a liquid L from a discharge port 28a of a discharge rod 28 inside of a preform 2 before and/or during molding the preform to a container C containing a liquid; a liquid blow molding step of supplying a pressurized liquid L from a supply path to inside of the preform 2 in a state where a blow nozzle 23 is engaged with a mouth part 2a of the preform 2 to mold the preform 2 to the container C containing the liquid having a shape along the inner surface of a die 10 for blow molding; and a head space formation step of discharging the liquid L from the inside of the container C containing the liquid via the discharge port 28a provided on the discharge rod 28 extending to the inside of the container C containing the liquid via the blow nozzle 23 in a state where the supply path is blocked to form a head space HS in the container C containing the liquid.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a method for producing a liquid-containing container for producing a liquid-containing container containing a content liquid from a synthetic resin preform.

  Synthetic resin containers such as polypropylene (PP) bottles and polyethylene terephthalate (PET) bottles contain various liquids such as beverages, cosmetics, chemicals, detergents, toiletries such as shampoos. Used for housing applications. Such a container is generally manufactured by blow-molding a preform formed of a synthetic resin material having thermoplasticity as described above.

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

  For example, in Patent Document 1, a preform made of a synthetic resin that has been heated to a temperature at which stretchability is developed in advance is mounted on a blow mold, and a pump or the like is added to the inside of the preform through a blow nozzle. A liquid blow molding method is described in which a liquid pressurized to a predetermined pressure by a pressure unit is supplied to form the preform into a container having a predetermined shape along a cavity of a blow molding die. .

  In the liquid blow molding method as described above, by using the content liquid finally contained in the container as the liquid to be supplied to the preform, the molding of the container and the filling of the content liquid into the container are simultaneously performed. It is possible to manufacture a liquid-containing container containing the content liquid. Therefore, according to the method for manufacturing a liquid container using liquid blow molding as described above, the liquid container can be manufactured at a low cost by omitting the filling process of the content liquid into the container after molding.

Japanese Patent No. 5806929

  In the conventional liquid blow molding method, it is usually required to form a head space having a desired size in a molded container. As a method of forming the head space, for example, immediately after forming a container containing liquid, the liquid inside the container is sucked by a pump through a blow nozzle, and the inside of the container is made negative, and then the inside of the container is opened to the atmosphere. Thus, it is conceivable to form a head space by introducing air into the container. However, the liquid present in the container immediately after molding is in a foamed state by entraining the air present in the preform. Therefore, in the method as described above, since the foamed liquid is introduced into the liquid supply path leading to the blow nozzle, air is mixed into the supply path, the stability of the molding conditions, the moldability of the container, etc. There is a possibility that the problem of lowering of the temperature will occur.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a liquid-filled container that can be manufactured accurately and at low cost so that the liquid-filled container has a predetermined internal volume and shape. It is to provide a manufacturing method.

  The method for producing a liquid-filled container according to the present invention is a method for producing a liquid-filled container for producing a liquid-filled container containing a content liquid from a synthetic resin preform using a nozzle unit and a blow mold. The nozzle unit extends from a pressurized liquid supply source to a branch part, a liquid common path extending from the branch part to the blow nozzle, and extends from the branch part to a discharge port provided in the discharge rod. A rod purging step for discharging liquid from the discharge port of the discharge rod inside the preform before and / or during the molding into the liquid container, and the blow nozzle By supplying the liquid pressurized by the pressurized liquid supply source from the supply path to the inside of the preform in a state of being engaged with the mouth of the preform. A liquid blow molding process for molding the preform into the liquid container having a shape along the inner surface of the blow mold, and the supply path is closed to the inside of the liquid container through the blow nozzle. A head space forming step of forming a head space in the liquid container by discharging the liquid from the inside of the liquid container through the discharge port provided in the extended discharge rod.

  The method for producing a liquid-filled container according to the present invention is the above-described configuration, wherein in the rod purge step, the total amount of the liquid discharged from the inside of the liquid-filled container through the discharge port in the head space forming step previously performed is the discharge port. It is preferable to discharge from the air.

  The method for producing a liquid-filled container according to the present invention, in the above-described configuration, is an air discharge for discharging the air inside the preform to the outside by supplying the liquid to the inside of the preform before the liquid blow molding step. It is preferable to further include a step.

  In the method for manufacturing a liquid-containing container according to the present invention, in the above configuration, the amount of liquid discharged from the inside of the liquid-containing container through the discharge port in the head space forming step is equal to or less than an internal volume of the discharge path. preferable.

  In the method for producing a liquid-filled container according to the present invention, in the above configuration, in the head space forming step, the pressurized liquid supply source is operated in a suction direction, whereby the liquid-filled container is formed through the discharge port of the discharge rod. It is preferred to drain the liquid from the inside.

  In the method for manufacturing a liquid-filled container according to the present invention, in the above configuration, in the head space forming step, by introducing a pressurized gas into the liquid-filled container, the liquid-filled container is introduced through the discharge port of the discharge rod. The liquid is preferably discharged from the inside of the container.

  The method for producing a liquid-filled container according to the present invention is the above-described configuration, wherein in the head space forming step, before the liquid is discharged from the inside of the liquid-filled container through the discharge port of the discharge rod, the pressurized liquid supply source It is preferable that the liquid is discharged from the inside of the liquid-containing container through the supply path by operating in the suction direction.

  The method for producing a liquid-filled container according to the present invention may further include a rod stretching step in which the preform is stretched in the axial direction by a stretching rod during the liquid blow molding step or before the liquid blow molding step. And it is preferable that the said discharge rod is the said extending | stretching rod.

  In the method for manufacturing a liquid-containing container according to the present invention, in the above configuration, it is preferable that the liquid is discharged from the discharge port of the discharge rod in the liquid in the rod purge step.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the liquid containing container which can manufacture a liquid containing container accurately and at low cost so that it may have a predetermined internal volume and shape can be provided.

It is explanatory drawing which shows an example of the manufacturing apparatus of the container containing a liquid used for the manufacturing method of the container containing a liquid which is one Embodiment of this invention in the state which is performing the standby process. It is explanatory drawing which shows the manufacturing apparatus of the container with a liquid of the state which is performing the air discharge process. It is explanatory drawing which shows the manufacturing apparatus of the container containing a liquid of the state which is performing the rod purge process and the liquid blow molding process. It is explanatory drawing which shows the manufacturing apparatus of the container containing a liquid at the time of completion of a liquid blow molding process. It is explanatory drawing which shows the manufacturing apparatus of the container containing a liquid of the state which is performing the 1st stage suckback in a head space formation process. FIG. 6 is an explanatory diagram showing a liquid-filled container manufacturing apparatus when the supply path is closed from the state of FIG. 5 in the head space forming step. FIG. 7 is an explanatory diagram illustrating a liquid-filled container manufacturing apparatus in a state where a head space is formed by starting the second stage suck-back from the state of FIG. 6 in the head space forming step. It is explanatory drawing which shows the manufacturing apparatus of the container containing a liquid of the state which is performing the rod raising / depressurizing process.

  Hereinafter, the present invention will be described in more detail with reference to the drawings.

  A method for producing a liquid-filled container according to an embodiment of the present invention includes a liquid-filled container for producing a liquid-filled container containing a content liquid from a synthetic resin preform using a nozzle unit and a blow mold. In the manufacturing method, the nozzle unit includes a liquid common path extending from the pressurized liquid supply source to the branching part, a liquid supply path extending from the branching part to the blow nozzle, and a discharge port provided in the discharge rod from the branching part. A rod purge step for discharging the liquid from the discharge port of the discharge rod inside the preform before and / or during the molding into the liquid container, and the blow nozzle as a preform. The preform is blow-molded by supplying the liquid pressurized by the pressurized liquid supply source from the supply path to the inside of the preform while being engaged with the mouth portion of the preform. Liquid blow molding process for forming into a liquid filled container shaped along the inner surface, and a liquid filled container through a discharge port provided in a discharge rod extending through the blow nozzle to the inside of the liquid filled container with the supply path closed And a head space forming step of forming a head space in the liquid container by discharging the liquid from the inside of the container.

  In the method for manufacturing a liquid container according to this embodiment, in the rod purging process, the entire amount of liquid discharged from the inside of the liquid container through the discharge port in the head space forming process performed last time is discharged from the discharge port.

  The method for manufacturing a container with a liquid according to the present embodiment further includes an air discharging step of discharging the air inside the preform to the outside by supplying the liquid to the inside of the preform before the liquid blow molding step. Yes.

  In the method for manufacturing a liquid container according to the present embodiment, the amount of liquid discharged from the inside of the liquid container through the discharge port in the head space forming step is equal to or less than the internal volume of the discharge path.

  In the manufacturing method of the liquid container according to the present embodiment, in the head space forming step, the liquid is discharged from the inside of the liquid container through the discharge port of the discharge rod by operating the pressurized liquid supply source in the suction direction. ing.

  In the method for manufacturing a liquid container according to the present embodiment, the liquid is discharged from the inside of the liquid container through the discharge port of the discharge rod by introducing a pressurized gas into the liquid container in the head space forming step. I am doing so.

  In the method for manufacturing a liquid container according to the present embodiment, in the head space formation step, before the liquid is discharged from the liquid container through the discharge port of the discharge rod, the pressurized liquid supply source is operated in the suction direction. The liquid is discharged from the inside of the liquid container through the supply path.

  The method for producing a liquid-filled container according to this embodiment further includes a rod stretching step in which the preform is stretched in the axial direction by a stretching rod during the liquid blow molding step, and the discharge rod is a stretching rod.

  In the method for manufacturing a liquid-containing container according to the present embodiment, the liquid is discharged from the discharge port of the discharge rod in the liquid in the rod purge step.

  Such a method for producing a liquid container according to the present embodiment can be carried out, for example, using the liquid container producing apparatus 1 having the configuration shown in FIG.

  A liquid-filled container manufacturing apparatus 1 shown in FIG. 1 manufactures a liquid-filled container C (see FIG. 4) containing a content liquid from a synthetic resin preform 2. As the liquid (content liquid) L stored in the container C with liquid, various liquids L such as beverages, cosmetics, chemicals, detergents, toiletries such as shampoos can be used.

  As the preform 2, for example, a synthetic resin material having thermoplasticity such as polypropylene (PP) or polyethylene terephthalate (PET) is connected to the cylindrical mouth portion 2 a serving as the opening end and the mouth portion 2 a and the lower end is closed. What was formed in the bottomed cylinder shape which has the cylindrical trunk | drum 2b which can be used can be used.

  Although not shown in detail, on the outer wall surface of the mouth portion 2a, an engagement protrusion for mounting a closing cap (not shown) on the mouth portion 2a of the molded liquid container C by stoppering (undercut engagement). Is provided. In addition, it can also be set as the structure which replaces with an engagement protrusion on the outer wall surface of the opening part 2a, and provides an obstruction | occlusion cap to the opening part 2a by screw coupling.

  The liquid container manufacturing apparatus 1 has a blow molding die 10. The blow molding die 10 has a cavity 11 having a shape corresponding to the final shape of the liquid container C such as a bottle shape. The cavity 11 opens upward on the upper surface of the blow molding die 10. In the preform 2, the body portion 2 b is disposed inside the cavity 11 of the blow molding die 10, and the mouth portion 2 a protrudes upward from the blow molding die 10. It is attached to.

  The blow molding die 10 can be opened to the left and right, and after the preform 2 is molded into the liquid container C, the blow molding die 10 is opened to the left and right so that the liquid container can be opened. C can be taken out from the blow molding die 10.

  Above the blow mold 10, a nozzle unit 20 for supplying pressurized liquid L to the inside of the preform 2 is provided. The nozzle unit 20 has a main body block 21.

  A support block 22 is provided at the lower end of the main body block 21, and a blow nozzle 23 is attached to the lower end of the main body block 21 supported by the support block 22. The blow nozzle 23 is formed in a substantially cylindrical shape, and the inner side of the lower end thereof is a liquid supply port 23a. The main body block 21, the support block 22, and the blow nozzle 23 constitute a nozzle unit main body 20a. The nozzle unit main body 20a is movable relative to the blow molding die 10 in the vertical direction. When the nozzle unit main body 20a is lowered to the lower stroke end, the nozzle unit main body 20a (more specifically, the blow nozzle 23) is placed in the mouth 2a of the preform 2 attached to the blow molding die 10. Engage in a sealed state from above.

  In the nozzle unit main body 20a (more specifically, the main body block 21 and the blow nozzle 23), a vertical flow path 24 extending to the liquid supply port 23a of the blow nozzle 23 is provided. The vertical flow path 24 extends in the vertical direction.

  The nozzle unit main body 20 a (more specifically, the main body block 21) is provided with a supply port 25 that communicates with the upper end of the longitudinal flow path 24.

  The nozzle unit main body 20 a (more specifically, the blow nozzle 23) has an annular (annular) seat portion 24 a provided in the longitudinal flow path 24. The annular seat portion 24 a is configured by the upper surface of the blow nozzle 23. The annular seat portion 24 a may be configured by the inner peripheral surface of the blow nozzle 23, or may be configured by the upper surface and the inner peripheral surface of the blow nozzle 23. The annular seat portion 24a has a downward conical tapered surface. However, the shape of the annular seat portion 24a can be changed as appropriate. Inside the longitudinal flow path 24, a seal body 26 for opening and closing the longitudinal flow path 24 (the seat portion 24a) is disposed. The seal body 26 is formed in a cylindrical shape, and a downward conical tapered surface 26 a is provided at the lower end of the seal body 26. When the seal body 26 moves to the closed position, which is the stroke end position on the lower side, the taper surface 26a abuts against the upper surface (seat portion 24a) of the blow nozzle 23 and the longitudinal flow path 24 (seat portion 24a). Occlude. The tapered surface 26a is provided at the lower end of the seal body 26, but its arrangement can be changed as appropriate. The tapered surface 26a has a conical shape downward, but the shape can be changed as appropriate. On the other hand, when the seal body 26 moves upward from the closed position, the lower end surface of the seal body 26 is detached from the upper surface (seat portion 24a) of the blow nozzle 23, and the vertical flow path 24 (seat portion 24a) is opened. The

  The seal body 26 has a closing position at which the longitudinal flow path 24 (the seat portion 24a) is closed, and a maximum opening degree that is an opening that maximizes the longitudinal flow path 24 (the seat portion 24a) in the liquid blow molding process. It is possible to move between the open position where it is opened. More specifically, the seal body 26 is movable between a closed position (see FIG. 1), a preliminary open position (see FIG. 2), and an open position (see FIG. 4). In the preliminary opening position, the opening degree of the seal body 26 that opens and closes the longitudinal flow path 24 (the seat portion 24a) is smaller than the opening degree in the opening position. Preferably, the effective cross-sectional area of the longitudinal channel 24 at the preliminary open position is 10% or less of the effective cross-sectional area of the longitudinal channel 24 at the open position. As shown in FIG. 1, the seal body 26 is fixed to a shaft body 27 provided so as to be movable in the vertical direction relative to the nozzle unit body 20 a, and is movable in the vertical direction inside the vertical flow path 24. It has become. The seal body 26 may be formed integrally with the shaft body 27.

  The nozzle unit 20 has a discharge rod 28 provided with a discharge port 28a. The discharge rod 28 formed in a substantially cylindrical shape by a steel material or the like extends along the axial centers of the shaft body 27 and the seal body 26. The discharge rod 28 is driven by a drive source (not shown) and can move in the vertical direction relative to the shaft body 27 and the seal body 26. The discharge port 28a communicates with the first pipe P1 through a hollow portion (not shown) of the discharge rod 28. More specifically, the lower end portion of the hollow portion of the discharge rod 28 communicates with the discharge port 28a, and the upper end portion of the hollow portion of the discharge rod 28 communicates with the first pipe P1. A rod valve V1 is provided in the first pipe P1, and the first pipe P1 can be opened and closed by the rod valve V1. The rod valve V1 is preferably constituted by an electromagnetic valve that can be controlled by a control device. In the present embodiment, the lower end of the discharge rod 28 is closed, and the discharge port 28 a is provided on the peripheral wall of the discharge rod 28. Therefore, when the discharge rod 28 is pulled back to the original position after the formation of the head space HS (see FIG. 7) of the container C, liquid dripping hardly occurs. However, it is not limited to such a configuration, and the discharge port 28a may be provided on the lower end surface of the discharge rod 28 or on both the lower end surface and the peripheral wall.

  The discharge rod 28 may be used as a stretching rod as in this embodiment. The discharge rod 28 can extend the preform 2 in the axial direction by moving downward.

  Inside the nozzle unit 20 (nozzle unit main body 20a), a flow path 29 through which the liquid L and / or gas (air in the present embodiment) flows is provided. The flow path 29 is a portion downstream of the seat portion 24a (in this embodiment, the blow nozzle 23 of the supply path (the supply path is constituted by the third pipe P3, the supply port 25, and the vertical flow path 24)). A suction state in which the opening 31 provided in the inner peripheral surface) is connected to a suction source 32 capable of sucking the liquid L in the flow path 29 and a gas (air in the present embodiment) pressurized to the opening 31 are supplied. The pressurized state connected to the possible pressurized gas supply source 33, the open air state where the opening 31 is connected to the atmosphere, and the opening 31 is blocked from any of the suction source 32, the pressurized gas supply source 33 and the atmosphere. The closed state can be alternatively selected. As shown in FIGS. 1 and 8, dripping from the blow nozzle 23 can be prevented by setting the flow path 29 to the suction state. In the case where the contents are liquid that hardly causes dripping, or in the case where dripping may occur, the flow path 29 does not need to be in a suction state (a configuration in which the third path 29c and the suction source 32 are not provided). As well). As shown in FIG. 2, when the flow path 29 is opened to the atmosphere, air can be discharged from the inside of the preform 2 to the atmosphere (outside) through the flow path 29 in the air discharge step. Depending on the conditions, in the air discharging step, the air may be discharged from the inside of the preform 2 by setting the path 29 to a suction state instead of opening to the atmosphere. As shown in FIGS. 3 and 4, by closing the flow path 29, the pressurized liquid L can be stably supplied into the preform 2 in the liquid blow molding process. As shown in FIG. 7, when the flow path 29 is in a pressurized state, when the liquid L is discharged from the inside of the preform 2 through the discharge port 28 a of the discharge rod 28 in the head space forming process, Discharge of the liquid L can be promoted or supported by supplying pressurized gas (air) inside. The suction source 32 can be constituted by, for example, a suction pump. The pressurized gas supply source 33 can be composed of, for example, a pressure pump. The suction source 32 and the pressurized gas supply source 33 may be configured by a suction / pressure pump (for example, a plunger pump such as the pressurized liquid supply source 30) in which a suction pump and a pressure pump are integrated. . A part or the whole of the flow path 29 can be provided inside the nozzle unit 20 (nozzle unit main body 20a).

  In the present embodiment, as shown in FIG. 1, the flow path 29 includes a first path 29a provided with a first valve Va, a second path 29b provided with a second valve Vb, and a third valve Vc. It has a third path 29c provided, a fourth path 29d provided with a fourth valve Vd, and a fifth path 29e provided with a fifth valve Ve. One end of the first path 29 a is connected to the opening 31, and the other end is connected to the first branch part 34. One end of the second path 29b is connected to the second branch portion 35, and the other end is open to the atmosphere. One end of the third path 29 c is connected to the second branch portion 35, and the other end is connected to the suction source 32. One end of the fourth path 29 d is connected to the first branch part 34, and the other end is connected to the second branch part 35. One end of the fifth path 29 e is connected to the first branch portion 34, and the other end is connected to the pressurized gas supply source 33. The first to fifth valves Va to Ve are preferably constituted by electromagnetic valves.

  A pressurized liquid supply source 30 is connected to the supply port 25 by a second pipe P2. The pressurized liquid supply source 30 can be constituted by, for example, a plunger pump provided with a cylinder 30a and a piston (plunger) 30b.

  As shown in FIGS. 3 and 4, the pressurized liquid supply source 30 includes a blow nozzle 23 engaged in a sealed state with a mouth portion 2 a of the preform 2 attached to the blow molding die 10, and a seal body 26. In the state where the vertical flow path 24 is opened, the second pipe P2, the third pipe P3, the supply port 25, and the vertical flow path 24 (the seat portion 24a and the liquid supply) are operated in the forward direction (pressure direction). Pressurized liquid L can be supplied to the inside of the preform 2 through the mouth 23a). The second pipe P2 branches at the branch portion S into the first pipe P1 and the third pipe P3. The nozzle unit 20 includes a common path composed of a second pipe P2 extending from the pressurized liquid supply source 30 to the branch section S, a third pipe P3 extending from the branch section S to the supply port 25, the supply port 25, and the longitudinal flow path. And a discharge path (including the first pipe P1) extending from the branch portion S to the discharge port 28a provided in the discharge rod 28.

  As shown in FIG. 7, the pressurized liquid supply source 30 operates in the reverse direction when the seal body 26 closes the longitudinal flow path 24 and the rod valve V1 is opened, whereby the discharge port 28a of the discharge rod 28 is discharged. Through this, the liquid L can be discharged from the inside of the liquid container C into the discharge path from the discharge port 28a to the branch portion S.

  The pressurized liquid supply source 30 operates in the reverse direction when the seal body 26 closes the longitudinal flow path 24 and the rod valve V1 is closed, so that the liquid L contained in a supply tank (not shown) is supplied to the cylinder 30a. It is possible to prepare for the next liquid blow molding.

  Nozzle unit main body 20a, seal body 26, discharge rod (extension rod) 28, pressurized liquid supply source 30 (plunger 30b), rod valve V1, first to fifth valves Va to Ve, suction source 32, and pressurized gas The operations of the supply source 33 and the like are integrally controlled by a control device (not shown).

  Next, by using the liquid-filled container manufacturing apparatus 1 having such a configuration, a liquid-filled container C in which a liquid (content liquid) L is accommodated from a synthetic resin preform 2 into a container having a predetermined shape. A method for molding (a method for producing a liquid-containing container according to the present embodiment) will be described.

  First, a standby process is performed. In the standby process, the preform 2 that has been heated up to a predetermined temperature (for example, 80 ° C. to 150 ° C.) to develop stretchability by using a heating means (not shown) such as a heater is blow molded. Mount on mold 10 and clamp.

  At this time, as shown in FIG. 1, the nozzle unit 20 is located at a position away from the blow molding die 10 and the seal body 26 closes the seat portion 24a. The flow path 29 is in a suction state. More specifically, the first valve Va is opened, the second valve Vb is closed, the third valve Vc is opened, the fourth valve Vd is opened, and the fifth valve Ve is closed. At this time, since the opening 2a of the preform 2 is open, the preform 2 is in a state where the inside is filled with air.

  Next, in this embodiment, an air discharge process is performed. In the air discharge step, as shown in FIG. 2, the nozzle unit 20 is lowered, the blow nozzle 23 is engaged with the mouth 2a of the preform 2, and the flow path 29 is opened to the atmosphere. 26 is moved to the preliminary opening position, the plunger 30b is operated in the forward direction at the first speed (ie, at the first pressure), and the liquid L is supplied into the preform 2 from the longitudinal flow path 24 (supply path). By doing so, the air inside the preform 2 is discharged to the atmosphere (outside) through the flow path 29. That is, by supplying the liquid L into the preform 2, most of the air filled in the preform 2 is pushed out by the liquid L and discharged. At this time, in the flow path 29, the first valve Va is opened, the second valve Vb is opened, the third valve Vc is closed, the fourth valve Vd is opened, and the fifth valve Ve is closed. In addition, it is preferable to set the 1st speed | rate in an air discharge process to the grade which does not extend | stretch (expand) a preform substantially.

  When the air discharge process is completed, a liquid blow molding process is then performed. In the liquid blow molding process, pressure is applied from the longitudinal flow path 24 (supply path) to the inside of the preform 2 by the pressurized liquid supply source 30 with the blow nozzle 23 engaged with the mouth 2a of the preform 2. By supplying the liquid L, the preform 2 is formed into a liquid-containing container C having a shape along the cavity 11 of the blow molding die 10.

  In this embodiment, as shown in FIG. 3, a rod purge process is first performed at the beginning of this liquid blow molding process. In the rod purge step, first, the flow path 29 is closed, the rod valve V1 is opened, and then the plunger 30b is moved at a second speed higher than the first speed while the seal body 26 is held in the preliminary open position ( That is, the discharge port 28a of the discharge rod 28 is operated in the forward direction (with a second pressure higher than the first pressure) and in the liquid L inside the preform 2 before and / or during the formation of the liquid container C. Liquid L is discharged from In the present embodiment, all of the first to fifth valves Va to Ve are closed in the rod purge process and the liquid blow molding process. However, the third valve Vc may be opened in advance in preparation for the rod ascending / depressurizing step. Further, the fifth valve Ve may be opened in advance in preparation for the second stage suck back in the head space forming process.

  The liquid L discharged from the discharge port 28a of the discharge rod 28 in the previous head space formation process may be mixed with some air due to the vertical movement process of the discharge rod 28. If it is returned to the supply channel) and accumulated every time the container C is molded, the stability of the molding conditions (pressure of the liquid L during liquid blow molding, etc.) and the moldability of the container will be reduced. There is a fear. If the liquid L (preferably the entire amount) discharged from the discharge port 28a of the discharge rod 28 in the previous head space formation step is discharged into the preform 2 by the rod purge step, air accumulates in this way. Can be prevented. Further, in the above rod purge process, the amount of air supplied into the preform 2 is very small, so the influence on the moldability can be ignored. In the rod purge step, the liquid L is discharged from the discharge port 28 a in the liquid L inside the preform 2. Therefore, the occurrence of foaming inside the preform 2 can be suppressed.

  In this embodiment, the rod purge process is performed by operating the plunger 30b in the forward direction at the second speed while the seal body 26 is held in the preliminary open position, but the seal body 26 is moved to the open position. Alternatively, the plunger 30b may be operated in the forward direction at the second speed after being moved to the open position. Further, in order to more stably realize discharge from the discharge port 28a in the rod purge process, the rod body V1 is opened after the seal body 26 is moved to the closed position and the plunger 30b is operated in the forward direction (for example, , Second speed). Alternatively, an open / close valve is provided in the third pipe P3, and the open / close valve is closed and the rod valve V1 is opened (at this time, the seal body 26 may be kept in the preliminary open position, or may be moved to the open position). It is also possible to operate the plunger 30b in the forward direction (for example, the second speed).

  In the liquid blow molding process, when the rod purge process is completed, the seal body 26 is then raised from the preliminary open position toward the open position while the plunger 30b is operated in the forward direction at the second speed, The liquid L pressurized to the second pressure is supplied from the passage 24 (supply passage) through the seat portion 24 a to the inside of the preform 2. As a result, the preform 2 is formed into a liquid-containing container C having a shape along the cavity 11 of the blow molding die 10 as shown in FIG.

  Here, since the liquid blow molding process is performed in a state where most of the air inside the preform 2 is discharged to the outside in the air discharging process, when the pressurized liquid L is supplied to the inside of the preform 2 In this way, the liquid L does not entrain air, and this prevents the air from being mixed into the liquid L inside the liquid container C.

  In this embodiment, as shown in FIGS. 3 and 4, the rod stretching process is performed during the liquid blow molding process. In the rod stretching step, the body 2b of the preform 2 is stretched in the axial direction (longitudinal direction) by the stretching rod 28 that moves forward and downward. It can also be set as the structure which performs a rod extending process before a liquid blow molding process. By performing the liquid blow molding process after or during the rod stretching process (the rod stretching process may be started after the liquid blow molding process is started), while the preform 2 is stretched in the axial direction by the stretching rod 28 Since biaxial stretch blow molding that performs blow molding can be performed, the preform 2 can be molded into a liquid container C having a predetermined shape with higher accuracy. However, the liquid blow molding process may be performed without performing the rod stretching process. FIG. 1 shows a state in which the stretching rod 28 is in the original position. The lower end surface of the stretching rod 28 does not need to be located at the height shown in FIG. 1 in the original position, and may be located above or below the height.

  When the liquid blow molding process is completed, a head space forming process is then performed. As shown in FIG. 5, in the present embodiment, in the head space forming step, first stage suck-back is performed (that is, liquid is supplied through the supply path by operating the pressurized liquid supply source 30 in the suction direction). The liquid L is discharged from the inside of the container C). In the first-stage suckback, as shown in FIG. 5, the seal body 26 is in the open position, the flow path 29 is closed, and the rod valve V1 remains open (the rod valve V1 may be closed). Then, the plunger 30b is operated in the reverse direction (suction direction) by a predetermined operation amount, and a predetermined amount of liquid L is sucked back into the longitudinal flow path 24 (supply path) from the inside of the liquid-containing container C after molding. By this first stage suck-back, the positive pressure state inside the container C is eliminated (the negative pressure state may be changed), and then the liquid L is introduced from the inside of the container C when the flow path 29 is pressurized. Can be prevented from entering the flow path 29. Further, by performing this first stage suck-back through the longitudinal flow path 24 (supply path), the liquid L can be discharged more quickly than when only the discharge port 28a of the discharge rod 28 is passed, and the inside of the container C The positive pressure state can be quickly eliminated. The amount of sucking back by this first stage sackback is kept so small that some air mixed in the liquid L inside the molded container C is not returned to the longitudinal flow path 24 (supply path) as much as possible. It is preferable. However, this first stage suckback may not be performed.

  In the present embodiment, in the head space formation step, when the first stage suck-back is completed, the seal body 26 is moved to the closed position (see FIG. 6), and the flow path 29 is brought into a pressurized state, so that the second stage A suckback is performed (see FIG. 7). More specifically, in the flow path 29, as shown in FIG. 7, the first valve Va is opened, the second valve Vb is closed, the third valve Vc is closed, the fourth valve Vd is closed, and the fifth valve Ve. Is open. However, the third valve Vc may be opened in advance in preparation for the rod ascending / depressurizing step. In the second-stage suckback, by opening the rod valve V1 and operating the pressurized liquid supply source 30 (plunger 30b) in the suction direction with the longitudinal flow path 24 (supply path) closed, The liquid L is discharged from the inside of the liquid container C through the discharge port 28a provided in the discharge rod 28 extending to the inside of the liquid container C through the blow nozzle 23, and a head space HS is formed in the liquid container C. In the present embodiment, this second stage sackback is performed while supplying the pressurized gas from the flow path 29 to the inside of the preform 2, so that the discharge of the liquid L through the discharge port 28a is promoted. . This support by the pressurized gas is particularly effective when the viscosity of the liquid L as the content liquid is large. When the liquid L can be discharged from the discharge port 28a without assistance from pressurized gas, such as when the viscosity of the liquid L as the content liquid is small, the flow path 29 is opened to the atmosphere (or The blow nozzle 23 may be detached from the mouth 2a of the container C so that the atmosphere can be introduced from the outside), and the second stage suck back may be performed. As described above, when the second stage suckback is performed while introducing the gas into the preform 2, the flow path 29 is closed and the inside of the container C is made negative by the second stage suckback. After that, it is possible to form a larger head space HS without causing deformation (permanent deformation) due to excessive negative pressure in the container C as compared with the case where the flow path 29 is opened to the atmosphere and the head space HS is formed. it can. However, after the flow path 29 is closed and the inside of the container C is made negative pressure by the second stage suck back, the flow path 29 may be opened to the atmosphere to form the head space HS. In this case, the second-stage suckback may be performed simultaneously with the first-stage suckback (including partial overlap due to a time difference). Further, instead of the second stage suck back, the liquid L is discharged through the discharge port 28a only by the pressurized gas from the flow path 29 (that is, the pressurized liquid supply source 30 is closed in a state where the supply path is closed). By introducing pressurized gas into the liquid container C without operating in the suction direction, the liquid L is discharged from the liquid container C through the discharge port 28a of the discharge rod 28), and the head space HS is You may make it form.

  According to the discharge of the liquid L through the discharge port 28a as in the present embodiment, compared with the case where the liquid L is discharged through the vertical flow path 24 (the seat portion 24a), there is less air mixing. The liquid L can be discharged from the portion. For this reason, it is not essential to return the entire amount of the liquid L discharged through the discharge port 28a in the rod purge step (the amount that is expected to be mixed with air may be returned). In particular, in the present embodiment, as shown in FIG. 7, the discharge port 28a located in the lower half LP (the lower portion when the height is divided into two equal parts in the upper and lower directions) of the liquid container C with less air mixing. The liquid L is discharged from the inside of the container C with liquid. Instead of this, the liquid L may be discharged from the inside of the liquid container C through the discharge port 28a located in the upper half of the liquid container C. A plurality of discharge ports 28a may be provided in the discharge rod 28 along the axial direction and / or the circumferential direction. The arrangement position, the number, the shape, and the like of the discharge port 28a can be set as appropriate according to the type and nature of the liquid L.

  Further, in the head space forming step, the amount of the liquid L discharged from the inside of the liquid container C through the discharge port 28a is set to be equal to or less than the internal volume of the discharge path. Therefore, it is possible to prevent the discharged liquid L from entering the supply path (the longitudinal flow path 24, the supply port 25, and the third pipe P3) together with the air. From this point of view, it is preferable that the amount of the liquid L to be discharged from the inside of the liquid container C through the discharge port 28a in the head space forming step is equal to or less than the internal volume from the discharge port 28a to the rod valve V1 in the discharge path. Further, according to the present embodiment, the configuration of the nozzle unit 20 can be simplified by using the pressurized liquid supply source 30 for pressurizing the supply path also for the discharge. However, the amount of the liquid L discharged from the inside of the liquid container C through the discharge port 28a in the head space forming step may be larger than the internal volume of the discharge path.

  In the present embodiment, when the head space forming process is completed, a rod lifting / depressurizing process is performed. In the rod raising / depressurizing step, as shown in FIG. 8, the discharge rod (stretching rod) 28 is raised and returned to the original position. Moreover, the flow path 29 is made into a suction state, and the rod valve V1 is closed. Next, the nozzle unit 20 is raised, and the liquid container C is taken out from the blow mold 10. And the pressurized liquid supply source 30 is filled, and it transfers to the standby process shown in FIG.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  For example, in the above-described embodiment, the case where the method for manufacturing a liquid container according to the present invention is performed using the apparatus 1 for manufacturing a liquid container having the configuration shown in FIG. The manufacturing method of the container with a liquid of this invention can also be performed using an apparatus etc.

  In the embodiment described above, the interior of the preform 2 is opened to the atmosphere by opening the flow path 29 to the atmosphere with the blow nozzle 23 engaged with the mouth portion 2a of the preform 2 in the air discharging step. However, it is not limited to this. For example, in the air discharging step, the blow nozzle 23 may not be engaged with the mouth portion 2a of the preform 2, and an air discharging passage from the inside of the preform 2 to the outside may be secured.

  In the above-described embodiment, the pressurized liquid supply source 30 is a plunger pump. However, the present invention is not limited to this, and the liquid L can be pressurized to a predetermined pressure and supplied to the preform 2. As long as it can generate a negative pressure for sucking back L, various types of pumps and the like can be used.

  In the above-described embodiment, in the rod purge step, the liquid L is discharged from the discharge port 28a of the discharge rod 28 in the liquid L inside the preform 2 before and / or during the formation of the liquid container C. However, it is not limited to this. For example, in the rod purge step, the liquid L may be discharged from the discharge port 28a of the discharge rod 28 in the air at all times. In the above embodiment, in the rod purging process, the liquid L is always discharged from the discharge port 28a in the liquid L inside the preform 2. For example, the initial stage of discharge is air. It may be performed in the liquid L and thereafter. Further, before the rod purge step (for example, before the standby step), a step of supplying the liquid L into the preform 2 in advance by means other than the blow nozzle 23 may be provided. Moreover, in the said embodiment, although the rod purge process was performed during the liquid blow molding process, it is not restricted to this. For example, the rod purge process may be performed before the liquid blow molding process (for example, before or during the air discharge process, or between the air discharge process and the liquid blow molding process). In the rod purging process, the discharge of the liquid L from the discharge port 28a of the discharge rod 28 may be performed in the liquid L inside the liquid container C immediately after molding (before the first stage suck back) depending on conditions. You may go.

  In the above embodiment, the air discharging step is performed, but the air discharging step may not be performed.

  As the preform 2, those having various shapes can be used according to the shape of the molded liquid container C and the like.

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus of container with liquid 2 Preform 2a Mouth part 2b Body part 10 Mold for blow molding 11 Cavity 20 Nozzle unit 20a Nozzle unit main body 21 Main body block 22 Support block 23 Blow nozzle 23a Liquid supply port 24 Vertical flow path 24a Seat Portion 25 Supply port 26 Seal body 26a Tapered surface 27 Shaft body 28 Discharge rod (extension rod)
28a Discharge port 29 Flow path 30 Pressurized liquid supply source 30a Cylinder 30b Piston (plunger)
31 Opening 32 Suction source 33 Pressurized gas supply source 34 First branch part 35 Second branch part C Liquid container L Liquid P1 First pipe P2 Second pipe P3 Third pipe S Branch part V1 Rod valves Va to Ve First -5th valve HS Headspace LP Lower half

Claims (9)

A method for producing a liquid-containing container for producing a liquid-containing container containing a content liquid from a synthetic resin preform using a nozzle unit and a blow molding die,
The nozzle unit includes a liquid common path extending from the pressurized liquid supply source to the branching section, a liquid supply path extending from the branching section to the blow nozzle, and a liquid extending from the branching section to a discharge port provided in the discharge rod. And a discharge route of
A rod purging step for discharging liquid from the discharge port of the discharge rod inside the preform before and / or during the formation of the liquid container;
By supplying the liquid pressurized by the pressurized liquid supply source from the supply path into the preform while the blow nozzle is engaged with the mouth of the preform, the preform is blown. A liquid blow molding step for molding the liquid container having a shape along the inner surface of the molding die;
By discharging the liquid from the inside of the liquid container through the discharge port provided in the discharge rod extending to the inside of the liquid container through the blow nozzle while the supply path is closed, the liquid A method for producing a liquid-containing container, comprising: a head space forming step of forming a head space in the containing container.   2. The production of a liquid-filled container according to claim 1, wherein, in the rod purge process, the entire amount of liquid discharged from the inside of the liquid-filled container through the discharge port in the head space forming process performed last time is discharged from the discharge port. Method.   The liquid entering according to claim 1, further comprising an air discharge step of discharging the air inside the preform to the outside by supplying the liquid into the preform before the liquid blow molding step. Container manufacturing method.   The amount of the liquid discharged | emitted from the inside of the said container with a liquid through the said discharge port in the said head space formation process is below the internal volume of the said discharge path | route, The container with a liquid as described in any one of Claims 1-3 Manufacturing method.   5. The liquid according to claim 1, wherein in the head space formation step, the liquid is discharged from the inside of the liquid container through the discharge port of the discharge rod by operating the pressurized liquid supply source in the suction direction. A method for producing a liquid-filled container according to one item.   The said head space formation process WHEREIN: By introduce | transducing pressurized gas into the inside of the said liquid container, a liquid is discharged | emitted from the inside of the said liquid container through the said discharge port of the said discharge rod. The manufacturing method of the container with a liquid as described in any one.   In the head space forming step, before discharging the liquid from the inside of the liquid container through the discharge port of the discharge rod, the liquid is supplied through the supply path by operating the pressurized liquid supply source in the suction direction. The manufacturing method of the container with a liquid as described in any one of Claims 1-6 which discharges | emits a liquid from the inside of a container. A rod stretching step of stretching the preform in the axial direction by a stretching rod during the liquid blow molding step or before the liquid blow molding step;
The said discharge rod is a manufacturing method of the container with a liquid as described in any one of Claims 1-7 which is the said extending | stretching rod.   The method for producing a liquid-containing container according to any one of claims 1 to 8, wherein in the rod purge step, the liquid is discharged from the discharge port of the discharge rod in the liquid.

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