JP2022029855A - Manufacturing method for resin container - Google Patents

Abstract

To provide a manufacturing system for a resin container in which the resin container is manufactured by injection stretch-blow molding that can adjust a temperature of a preform to achieve an optimum temperature condition for blow molding without reducing production efficiency.SOLUTION: In a manufacturing system 1 for a resin container, each time 24 preforms are injection molded, a temperature control unit 61 of a temperature control device 6 is moved to a preform receiving position 6A to accept a preform 2 into 24 of 72 temperature control pots 62, which are empty. Each time the temperature control unit 61 returns to a preform take-out position 6B, a preform transfer device 7 removes the preform 2 from the 24 temperature control pots 62 that have received the preform 2 first out of the 72 temperature control pots, and feeds them to a stretch-blow molding device 5 to apply stretch-blow molding to obtain 24 resin containers 3.SELECTED DRAWING: Figure 1

Description

In the present invention, a bottomed tubular or cup-shaped preform (primary premolded product) is molded by injection molding, the preform is brought into a temperature state above the glass transition point of the molding resin, and the preform in this temperature state is obtained. The present invention relates to a resin container manufacturing system for obtaining a resin container by blow molding or stretch blow molding.

Biaxial stretch blow molding is widely used in the production of resin containers such as PET bottles. The biaxial stretch blow molding method is divided into a hot parison method and a cold parison method according to the difference in the thermal history of the injection-molded preform (parison). The hot parison method is a method in which the preform shifts to the temperature control process in a state where the preform is not completely cooled and blow molding is performed. The hot parison method is also called a one-stage method because preform molding and blow molding are continuously performed in a series of molding systems. In the cold parison method, the injection-molded preform is cooled to room temperature and reheated by a blow molding machine to blow-mold the preform heated to a temperature state at which it can be blow-molded. The cold parison method is also called a two-stage method because the preform molding and the preform blow molding are performed by separate molding systems.

The former method for manufacturing a resin container by the hot parison method is described in Patent Documents 1 to 3. As described in these documents, in the method of manufacturing a resin container by the hot parison method, the principle is that the resin container is blow molded using the residual heat at the time of injection without completely cooling the preform. There is a method of transporting to the temperature control part and adjusting to a temperature state above the glass transition point of the molding resin, and a method of direct blow molding without going through the temperature control process, both of which are molded by molding a resin container. The plastic container is transported to the container take-out section and collected at a predetermined collection location. In the injection molding of a preform, it takes time to cool the injection-molded preform to a state where it can be taken out from the injection molding mold. In order to increase production efficiency, a large number of molds are used in injection molding. In addition, by utilizing the concave outer peripheral surface shape of the screwed mouth of the preform, the mouth is gripped by mechanical engagement, and the preform is transported along the transport path passing through each part. The blow-molded container is taken out from the mold and collected.

International Publication No. 2017/14243 International Publication No. 2017/073685 Japanese Unexamined Patent Publication No. 2020-37773

As described in Patent Documents 1 to 3, in injection blow molding by the hot parison method, the injection-molded preform is transferred from the injection-molded part to the temperature control part, the blow-molded part and the take-out part at a constant time interval. It is transported intermittently in sequence. Depending on the type of molding resin, the wall thickness, shape, size, etc. of the preform, the time required to control the temperature of the preform in the temperature control section to form the optimum temperature state for blow molding also varies. .. For example, the temperature adjustment time of a thick-walled preform generally takes longer than that of a thin-walled preform. If the processing time in the temperature control section is long, the processing time in the temperature control section becomes a bottleneck, the tact time of the manufacturing system becomes long, and the production efficiency may decrease. Further, in the temperature control part, if the preform is not in the optimum temperature state for blow molding, each part of the preform cannot be appropriately stretched and blown in the stretch blow molding, and a container having the target characteristics can be obtained. It may not be possible.

On the other hand, some resin containers are used as containers for lactic acid beverages. The mouth of such a container has no screws and has a flange that surrounds the outer periphery of the mouth. The mouth of the container is sealed by attaching a film such as aluminum foil to the top surface of the flange by a method such as heat sealing. This type of container is generally manufactured by vacuum forming, extrusion blow molding. When manufactured by biaxial stretch blow molding, the outer peripheral surface of the mouth, as used in a manufacturing system for containers with a threaded mouth, such as PET bottles, which is common especially in the two-stage method. There is a problem that a preform transfer tool or a container transfer tool having a structure for gripping the mouth portion of the preform by mechanical engagement cannot be used by utilizing the concave shape of the above.

That is, in a container having a screw portion on the outer peripheral surface of the mouth portion, the mouth portion of the preform is gripped by using the screw portion or the support ring on the lower side of the screw portion, and the injection molding portion is passed through the temperature control portion. It is sent to a blow molding mold, and the container obtained by blow molding is sent out to a take-out part. In a container with a screwless mouth, such a preform transfer tool or transfer mechanism cannot be used to reliably grip the mouth of the preform ejected from the injection mold, and therefore the push. It is difficult to move the reform at high speed and surely along the transport path passing through the temperature control section, the blow molding section, and the take-out section.

In view of these points, an object of the present invention is to manufacture a resin container by injection blow molding, which can adjust the temperature of the preform so as to obtain the optimum temperature state for blow molding without lowering the production efficiency. The purpose is to propose a method for manufacturing a resin container.

Further, an object of the present invention is that the temperature of the preform can be adjusted without lowering the production efficiency, and a resin container having a mouth portion without a screw portion is passed through each step for injection blow molding. The purpose is to propose a method for manufacturing a resin container that can be efficiently transported at high speed to manufacture a resin container.

In order to solve the above problems, the present invention
An injection molding process in which a preform made of a plurality of bottomed cylinder-shaped or cup-shaped thermoplastic resins is injection-molded at the same time by an injection molding device, cooled to below the glass transition point in the injection molding mold, and taken out.
A plurality of the preforms taken out from the injection molding die are received in the temperature control pot of the temperature control device, and the temperature is adjusted so that the preforms can be blow-molded in the temperature control pot. Preparation process and
The preform transfer device takes out a plurality of the preforms in a temperature state capable of blow molding from the temperature control pot, transfers the taken out preforms to the blow molding device, and a plurality of blow molding dies of the blow molding device. And the transfer process to insert into
In a method for manufacturing a resin container, which comprises a blow molding step of forming a plurality of resin containers by performing blow molding or stretch blow molding on each of the preforms in the blow molding mold of the blow molding apparatus.
When N is an integer of 2 or more in a temperature control pot group having a number of the temperature control pots capable of accepting a plurality of the preforms to be injection-molded at the same time in the injection molding mold, the temperature control device can be used. Arrange N sets and
When the empty temperature control pot group that does not contain the preform is defined as an empty temperature control pot group,
Until the injection molding process is performed a plurality of times of N times or less.
The temperature control step is performed in parallel each time the injection molding step is performed without performing the transfer step and the blow molding step, and the injection-molded preform is put into one set of the empty temperature control pots. Accept each of the temperature control pots to which the temperature control pot belongs and start the temperature adjustment.
After performing the injection molding step a plurality of times,
Each time the injection molding step is performed, the transfer step, the blow molding step, and the temperature control step are performed in parallel.
The temperature control pot group containing the preform injection-molded in the injection molding step performed at the earliest time is set as the temperature control pot group to be taken out from the preform.
In the transfer step, the preform is taken out from each of the temperature control pots belonging to the temperature control pot group to be taken out from the preform, transferred to the blow molding apparatus, inserted into the blow molding mold, and inserted into the blow molding mold.
In the blow molding step, the preform inserted in the blow molding mold is blow molded or stretch blow molded to form a plurality of the resin containers.
The temperature control step is characterized in that the injection-molded preform is received in each of the temperature control pots belonging to the set of empty temperature control pots and the temperature control is started.

In the method for manufacturing a resin container of the present invention, preforms simultaneously taken out from a large number of injection molding molds of an injection molding apparatus are sequentially taken out, for example, in each of the first to Nth temperature control pots of the temperature control apparatus. The preform is temperature controlled to be acceptable and temperature conditions suitable for blow molding. After the preform is accepted in each of the first to Nth temperature control pot groups, that is, in each of the injection molding steps after the N + 1th time, the temperature control pot group that first received the preform, for example, the first. Preforms are taken out from each of the temperature control pots of the 1 temperature control pot group and sent to a blow molding mold, and blow molding is performed to form a resin container. Each of the preforms received in the temperature control pots of the first temperature control pot group is subjected to temperature adjustment during the (N-1) injection molding steps from the second to the Nth times.

Therefore, unlike the case of the conventional injection blow molding system, the processing time required for one injection molding step does not limit the temperature adjustment time of the preform in the temperature control step. Therefore, it is possible to secure a sufficient temperature adjustment time required for the preform. Further, for example, the temperature adjustment time of the preform can be increased or decreased by increasing or decreasing the number N of the temperature control pot group. Therefore, even preforms having different wall thicknesses and preforms having different shapes can be heated to the optimum temperature state for blow molding in the temperature control pot without lowering the production efficiency.

In a multi-piece blow molding apparatus, for example, a plurality of the blow molding dies are arranged at a predetermined arrangement pitch. In this case, in the injection molding die of the injection molding apparatus, the pair of male and female molds defining the injection molding cavity for injection molding the preform has the same pitch as the arrangement pitch of the blow molding die. Arrange with. Further, in each of the temperature control pot groups of the temperature control device, the temperature control pots are arranged at the same pitch as the arrangement pitch of the blow molding mold. Further, in the preform transfer device, a plurality of insertion cores that can be inserted into the mouth of the preform are arranged at the same pitch as the arrangement pitch of the blow molding mold.

In conventional systems, it is generally necessary to perform pitch conversion during the transfer of preforms so that multiple preforms that are injection molded at the same time at a narrow pitch can be fitted to a blow molding mold with a wider array pitch. be. In the present invention, the arrangement pitch of each part matches the arrangement pitch of the blow molding die. There is no need to convert the array pitch of the preform during the preform transfer. Since the pitch conversion mechanism and its installation space are not required, the preform transfer device and transfer mechanism can be configured simply and compactly.

In the production method of the present invention, the delivery of the preform in each process can be performed as follows. First, in the step of receiving the preform from the injection molding die into the temperature control pot, the preform attached to the male mold in the mold-opened state in the injection molding apparatus is coaxially described. Each of the temperature control pots is confronted, the preform ejected from the male mold is projected by an eject plate, and further vacuum suction is performed to receive the preform in the temperature control pot, and the preform is placed on the inner surface of the temperature control pot. Keep the outer surface in close contact.

Further, in the step of taking out the preform from the temperature control pot, each of the temperature control pots belonging to the temperature control pot group containing the preform to be taken out is inserted into the insertion core of the preform transfer device. Positioned at a take-out position that can be inserted coaxially with the mouth of the preform, the vacuum suction of the preform in the temperature control pot is released, and the mouth of the preform in the temperature control pot is released. The preform can be delivered to the insertion core coaxially inserted into the portion, and the preform is vacuum-sucked into the insertion core inserted into the mouth of the preform, or the insertion core is expanded. The preform is supported on the insertion core by mechanically engaging the insertion core with the inner peripheral surface of the mouth.

Further, in the step of inserting the preform carried on the insertion core into the plurality of blow molding dies, each of the insertion cores is placed directly above each of the blow molding dies that are open upward. Positioned so as to face each other coaxially, the preform carried on each of the insertion cores is inserted into each of the blow molding molds, the vacuum suction or mechanical engagement is released, and the insertion core is released. The preform is removed from the mold and handed over to the blow molding mold.

In this way, the transfer and delivery of the preform in each step can be performed without mechanically gripping the mouth portion of the preform from the outer peripheral side. Therefore, it is possible to transfer and deliver the preform in a shape that cannot use the mechanism for transferring the preform by mechanically grasping the mouth portion by using the concave shape of the screw portion on the outer periphery of the mouth portion at high speed and reliably. Can be done.

(A) is an explanatory view showing a plane layout of a main part of a resin container manufacturing system by injection stretch blow molding to which the present invention is applied, and (B) is an explanatory view showing an elevation layout of the main part. C) is a schematic cross section showing an example of a preform and a resin container. (A1) and (A2) are schematic plan views and schematic cross-sectional views showing the arrangement state of the temperature control pots of the temperature control unit, and (B1) and (B2) are schematic plan views and schematic views showing the arrangement state of the insertion cores. It is a side view, and (C1) and (C2) are a schematic plan view and a schematic cross-sectional view showing a stretch blow molding die. (A1), (B1), and (C1) are temperature control units positioned at the eject position of the injection molding device, the position of the temperature control pot for receiving the preform, and the temperature control unit positioned at the take-out position of the transfer device. It is explanatory drawing which shows, (A2), (B2), (C2) is the explanatory diagram which shows the 1st to 3rd temperature control pot group. It is explanatory drawing which shows the stretch blow molding apparatus. (A) to (E) are explanatory views showing the movement of the preform transfer device and the movement of the stretch blow molding device. It is a flowchart which shows the operation of the manufacturing apparatus of a resin container. It is a flowchart which shows the operation of the manufacturing apparatus of a resin container.

Hereinafter, embodiments of a resin container manufacturing system for manufacturing a resin container by injection stretch blow molding to which the present invention is applied will be described with reference to the drawings. It should be noted that the following embodiments show an example of the present invention, and the present invention is not intended to be limited to the embodiments. For example, it goes without saying that the shape of the manufactured resin container and the shape of the preform may be different. Further, various mechanisms such as a multi-axis stage mechanism and a scalar robot can be used as the movement mechanism in each part. Further, although the 24-piece mold is used in the embodiment, it is needless to say that a large number of molds other than this may be used.

FIG. 1 (A) is an explanatory view showing a planar layout of a main part of a resin container manufacturing system by injection stretch blow molding according to an embodiment to which the present invention is applied, and FIG. 1 (B) shows an elevation layout of the main part. It is explanatory drawing which shows, (C) is a schematic cross-sectional view showing an example of a preform obtained by injection molding and a resin container obtained by biaxially stretching and blowing this preform.

(Examples of preforms and resin containers)
First, with reference to FIG. 1 (C), a preform 2 which is injection-molded in the resin container manufacturing system 1 and a resin container 3 obtained by subjecting the preform 2 to biaxial stretch blow molding will be described. The resin container 3 of this example is, for example, a milk beverage container, and surrounds a cylindrical body portion 3a with a bottom, a mouth portion 3b formed at the upper end portion of the cylindrical body portion 3a, and an upper end edge of the mouth portion 3b. It is provided with an annular flange 3c formed in a state. No threaded portion is formed on the outer peripheral surface of the mouth portion 3b, and no support ring or the like is attached. After filling the resin container 3 with the contents, the mouth portion 3b is sealed with a film (not shown) such as aluminum foil attached to the upper surface of the flange 3c by a method such as heat sealing.

The preform 2 used for manufacturing the resin container 3 has a cylindrical body portion 2a with a bottom, a mouth portion 2b formed at the upper end portion of the cylindrical body portion 2a, and a state surrounding the upper end edge of the mouth portion 2b. It is provided with an annular flange 2c formed. The cylindrical body portion 2a is a portion that is subjected to stretch blow molding to become the cylindrical body portion 3a of the resin container 3. The mouth portion 2b and the flange 2c are portions that become the mouth portion 3b and the flange 3c of the resin container 3 as they are without being subjected to stretch blow molding. The molding resin of Preform 2 is a thermoplastic resin that can be stretch-blow molded.

The resin container manufacturing system 1 of this example is suitable for manufacturing a milk drink container made of PET resin and a cup-shaped or pot-shaped yogurt container. PET resin is a resin that is recycled and reused worldwide and is also suitable for environmental problems. On the other hand, many milk drinks and yogurt containers use a large amount of styrene resin-based materials, and most of them have a flange shape and do not have a threaded portion on the outer peripheral surface of the mouth.

(Overall configuration of resin container manufacturing system)
Explaining with reference to FIGS. 1A and 1B, the resin container manufacturing system 1 (hereinafter, simply referred to as “manufacturing system 1”) has a large number of preforms 2 that can be molded at the same time. A large number of stretch blows for obtaining a resin container 3 by performing stretch blow molding on an injection molding apparatus 4 equipped with a take injection molding die 40 and a preform 2 in a state adjusted to a temperature at which stretch blow molding is possible. It is provided with a stretch blow molding apparatus 5 provided with a molding die 52. Further, the manufacturing system 1 includes a temperature control device 6 provided with a temperature control unit 61 in which a plurality of temperature control pots 62 for controlling the temperature of the injection-molded preform 2 are arranged, and the preform 2 after the temperature control. The preform transfer device 7 is provided with a preform transfer device 7 for transferring the machine to the stretch blow molding device 5 and inserting it into the stretch blow molding die 52, and a control device 8 for controlling the drive of each part.

The temperature control pot 62 of the temperature control device 6 receives the preform 2 ejected from the injection molding mold 40 in the mold open state in the injection molding device 4 at the preform receiving position 6A. After receiving the preform 2, the temperature control pot 62 returns to the preform take-out position 6B away from the injection molding mold 40, and stands by here. In the temperature control pot 62, the preform 2 is adjusted to a temperature state suitable for stretch blow molding above the glass transition point of the molding resin. The temperature-adjusted preform 2 is taken out by the preform transfer device 7 at the take-out position 6B. The preform transfer device 7 transfers the preform 2 taken out from the temperature control pot 62 to the side of the stretch blow molding device 5 and inserts it into the stretch blow molding die 52 waiting at the preform insertion position 5A.

The stretch blow molding die 52 of the stretch blow molding apparatus 5 moves to the stretch blow position 5B after the preform 2 is inserted at the insertion position 5A. At the stretch blow position 5B, biaxial stretch blow is applied to each preform 2 inserted in the stretch blow molding die 52 to obtain a resin container 3. The stretch blow molding mold 52 is a split mold that can be opened and closed from side to side. The stretch blow molding mold 52 opens to the left and right, and the resin container 3 falls due to its own weight and is collected by the container collection unit 9 installed below.

(Injection molding equipment)
The injection molding device 4 is configured in the same manner as a general multi-cavity injection molding device. The injection molding die 40 of the injection molding apparatus 4 includes a female mold 43 attached to a fixed die plate and a male mold 44 attached to a moving die plate. For example, the injection molding die 40 is a die for taking 24 pieces. Therefore, 6 pairs of male type 44 and female type 43 are arranged at a constant pitch in the vertical direction. Four rows of six sets are arranged at a constant pitch in the left-right direction. The vertical arrangement pitch and the horizontal arrangement pitch of the pair of the male type 44 and the female type 43 are the same as the arrangement pitches in the vertical direction and the horizontal direction of the stretch blow molding type 52 having a large number of pieces.

In the closed state of the injection molding mold 40, a cavity for injection molding the preform 2 is formed between the male mold 44 and the female mold 43 of each set. Inside each of the male type 44 and the female type 43 of each set, a circulation path (not shown) for circulating cooling water set at 5 ° C to 20 ° C is formed. In the mold closed state, the molten thermoplastic resin is injected into the cavity between the male mold 44 and the female mold 43 of each set, and 24 preforms 2 are injection-molded at the same time. When the temperature of the preform 2 is cooled to a temperature lower than the glass transition point of the molding resin, the male mold 44 recedes from the mold clamping position 4A to the mold opening position 4B with respect to the female mold 43. The preform 2 is released from the female mold 43 and moves to the mold opening position 4B while being attached to the male mold 44. Next, the stripper plate (not shown) ejects (protrudes) the preform 2 from the male 44 in the axial direction thereof. In some cases, the preform 2 is surely ejected from the male type 44 by ejecting the eject air after a predetermined time.

(Temperature control device)
A temperature control device 6 is arranged on the side of the injection molding die 40 in the injection molding device 4. The temperature control device 6 includes a temperature control unit 61 in which a plurality of temperature control pots 62 are arranged, and a moving mechanism 63 for reciprocating the temperature control unit 61 in the horizontal direction. The temperature control unit 61 reciprocates between the preform receiving position 6A and the preform taking out position 6B by the moving mechanism 63. The temperature control unit 61 of this example has a rectangular plate shape having a constant thickness, and a plurality of temperature control pots 62 are arranged vertically and horizontally at a predetermined pitch in the temperature control unit 61.

2 (A1) and 2 (A2) are a schematic plan view and a schematic cross-sectional view showing an arrangement state of the temperature control pot 62 of the temperature control unit 61. The temperature control unit 61 is provided with a large number of temperature control pots 62. The number of temperature control pots 62 is N times or more (N is an integer of 2 or more) the number of preforms 2 that are injection-molded at the same time. In this example, 72 temperature control pots 62, which is three times as many, are provided.

Each temperature control pot 62 is horizontally opened at the vertical front surface 61a of the temperature control unit 61. The temperature control pot 62 has a row of temperature control pots in which six temperature control pots 62 are arranged in the vertical direction at a constant pitch (= p1) on the front surface 61a of the temperature control unit 61 in the horizontal direction. Twelve are formed at a constant pitch (= p2 / 3). Of these temperature control pots 62, 24 temperature control pots 62 included in the four temperature control pot rows of the first row, the fourth row, the seventh row, and the tenth row are used as the first temperature control pot group. It shall be called 62 (1). The temperature control pot 62 belonging to the first temperature control pot group 62 (1) is arranged at the same arrangement pitch as the male mold 44 and the female mold 43 of each set of the 24-piece injection molding mold 40, and is injection molded. The 24 preforms 2 to be formed can be accepted in each of the 24 temperature control pots 62 of the first temperature control pot group 62 (1). Therefore, the arrangement pitches of the temperature control pots 62 in the first temperature control pot group 62 (1) in the vertical direction and the left-right direction are the same as the arrangement pitches (p1, p2) of the stretch blow molding mold 52 having a large number of pieces.

Similarly, among the temperature control pots 62, the 24 temperature control pots 62 included in the four temperature control pot rows of the second row, the fifth row, the eighth row and the eleventh row are the second temperature control pots. It shall be referred to as a temperature control pot 62 of group 62 (2). The arrangement pitch of the temperature control pot 62 of the second temperature control pot group 62 (2) is also the same as the arrangement pitch of the injection molding mold 40 having 24 pieces. The 24 temperature control pots 62 included in the remaining four temperature control pot rows of the third row, the sixth row, the ninth row, and the twelfth row are combined with the temperature control of the third temperature control pot group 62 (3). It shall be called a pot 62. The temperature control pot 62 of the third temperature control pot group 62 (3) is also the same as the arrangement pitch of the injection molding mold 40 having 24 pieces.

Each temperature control pot 62 is a pot having an inner peripheral surface shape complementary to the outer peripheral surface shape of the preform 2, and the preform 2 is attached to the bottom of the temperature control pot 62 opened in the front surface 61a of the temperature control unit 61. It can be inserted coaxially from the side. In the state where the preform 2 is inserted, the outer peripheral surface of the preform 2 can be in close contact with the inner peripheral surface of the temperature control pot 62. The flange 2c of the preform 2 engages with the outer peripheral portion of the opening edge of the temperature control pot 62 that opens to the front surface 61a.

Inside the temperature control unit 61, a heat medium circulation path 64 is formed so as to surround each temperature control pot 62. The inner peripheral surface of the temperature control pot 62 is heated by the heat medium, and the preform 2 in contact with the inner peripheral surface is temperature-controlled. The temperature control pot 62 allows the preform 2 to be uniformly heated as a whole to a temperature state suitable for stretch blow molding above the glass transition point.

Inside the temperature control unit 61, a suction passage 65 communicating with the bottom of each temperature control pot 62 is formed. Each temperature control pot 62 was ejected from the male mold 44 by vacuum suctioning the inside of the temperature control pot 62 by a vacuum suction mechanism (not shown) in a state where each temperature control pot 62 faces coaxially with each male mold 44 of the injection molding mold 40. The preform 2 is surely accepted in the temperature control pot 62.

3 (A1), (B1) and (C1) are explanatory views showing the preform receiving position 6A and the preform taking out position 6B of the temperature control unit 61, respectively, and are FIGS. 3 (A2), (B2) and 3 (B2). (C2) is an explanatory diagram showing the first to third temperature control pot groups 62 (1) to 62 (3) of the temperature control unit 61, respectively. In FIG. 3 (A2), 24 temperature control pots 62 belonging to the first temperature control pot group 62 (1) are indicated by black circles. In FIG. 3 (B2), 24 temperature control pots 62 belonging to the second temperature control pot group 62 (2) are indicated by black circles. In FIG. 3 (C2), 24 temperature control pots 62 belonging to the third temperature control pot group 62 (3) are indicated by black circles.

As described below, the preform receiving position 6A of the temperature control unit 61 is a position where the temperature control unit 61 can accept the 24 simultaneously molded preforms 2. When the temperature control unit 61 is positioned at the preform receiving position 6A, each of the 24 temperature control pots 62 in the temperature control unit 61 becomes a respective of the 24 male molds 44 in the injection molding mold 40 in the mold open state. , It is possible to accept the preform 2 which is coaxially confronted from the horizontal direction and is ejected from the male type 44.

As shown in FIGS. 3 (A1) and 3 (A2), when the first temperature control pot group 62 (1) of the temperature control unit 61 is positioned at the preform receiving position 6A, the first temperature control pot group 62 (1) ), Each of the 24 temperature control pots 62 can accept the preform 2 ejected from each of the male molds 44 of the injection molding mold 40. As shown in FIGS. 3 (B1) and 3 (B2), when the second temperature control pot group 62 (2) of the temperature control unit 61 is positioned at the preform receiving position 6A, the second temperature control pot group 62 (2) ), Each of the 24 temperature control pots 62 can accept the preform 2 ejected from each of the male molds 44 of the injection molding mold 40. Similarly, as shown in FIGS. 3 (C1) and 3 (C2), when the third temperature control pot group 62 (3) of the temperature control unit 61 is positioned at the preform receiving position 6A, the third temperature control pot group Each of the 24 temperature control pots 62 belonging to 62 (3) can accept the preform 2 ejected from each of the male molds 44 of the injection molding mold 40.

Next, the preform take-out position 6B of the temperature control unit 61 is a position where the preform transfer device 7 can take out 24 preforms 2 from the temperature control unit 61. As shown in FIG. 3A, when the first temperature control pot group 62 (1) of the temperature control unit 61 is positioned at the preform take-out position 6B, it belongs to the first temperature control pot group 62 (1). The preform 2 can be taken out from the 24 temperature control pots 62 by the preform transfer device 7. As shown in FIG. 3 (B1), when the second temperature control pot group 62 (2) of the temperature control unit 61 is positioned at the preform take-out position 6B, it belongs to the second temperature control pot group 62 (2). The preform 2 can be taken out from each of the 24 temperature control pots 62 by the preform transfer device 7. As shown in FIG. 3 (C1), when the third temperature control pot group 62 (3) of the temperature control unit 61 is positioned at the preform take-out position 6B, it belongs to the third temperature control pot group 62 (3). The preform 2 can be taken out from each of the 24 temperature control pots 62 by the preform transfer device 7.

(Preform transfer device)
Explaining with reference to FIGS. 1 and 2, the preform transfer device 7 is arranged in front of the front surface 61a of the temperature control unit 61 located at the preform take-out position 6B. The preform transfer device 7 includes a rectangular plate-shaped preform supporting unit 71 and a supporting unit moving mechanism 73 for moving the preform supporting unit 71 to the preform taking-out position 6B and the preform insertion position 5A.

On the front surface of the preform carrying unit 71, 24 insertion cores 72 that can be inserted into the mouth portion 2b of the preform 2 are arranged. 2 (B1) and 2 (B2) are explanatory views showing the arrangement state of the insertion core 72 and the internal structure of the preform carrying unit 71. The vertical and horizontal arrangement pitches of the 24 insertion cores 72 are the same as the arrangement pitches of the 24 temperature control pots 62 belonging to each of the first to third temperature control pot groups of the temperature control unit 61. That is, it is the same as the arrangement pitch (p1, p2) of the 24-piece stretch blow molding die 52.

As shown in FIG. 3A, when the first temperature control pot group 62 (1) of the temperature control unit 61 is waiting at the preform take-out position 6B, the preform carrying unit 71 is placed at the preform take-out position 6B. When moved to, each of the 24 insertion cores 72 can be inserted coaxially with each of the 24 temperature control pots 62 belonging to the first temperature control pot group 62 (1) from the horizontal direction. As shown in FIG. 3B, when the second temperature control pot group 62 (2) of the temperature control unit 61 is waiting at the preform take-out position 6B, the preform carrying unit 71 is placed at the preform take-out position 6B. When moved to, each of the 24 insertion cores 72 can be inserted coaxially from the horizontal direction into each of the 24 temperature control pots 62 belonging to the second temperature control pot group 62 (2). Similarly, as shown in FIG. 3 (C1), when the third temperature control pot group 62 (3) of the temperature control unit 61 is waiting at the preform take-out position 6B, the preform carrying unit 71 is preformed. When moved to the take-out position 6B, each of the 24 insertion cores 72 can be inserted coaxially from the horizontal direction into each of the 24 temperature control pots 62 belonging to the third temperature control pot group 62 (3). Is.

In this example, the temperature control unit 61 is moved, and each of the first to third temperature control pot groups 62 (1) to 62 (3) is positioned at the preform take-out position 6B. Of course, the preform carrier unit 71 may be moved and positioned in each of the first to third temperature control pot groups 62 (1) to 62 (3) of the temperature control unit 61.

The carrying unit moving mechanism 73 of this example moves the preform carrying unit 71 horizontally toward and away from the temperature control unit 61 waiting in the vertical posture at the preform taking-out position 6B in the vertical posture. It is provided with a horizontal movement mechanism (not shown) for moving, a turning mechanism 75 for turning the preform carrying unit 71 from a vertical posture to a downward horizontal posture, and an elevating mechanism 76 for moving the preform carrying unit 71 up and down in the vertical direction. ing. Various mechanisms can be adopted as the carrier unit moving mechanism 73, and for example, a scalar robot can be used to move the carrier unit in three axial directions.

The preform supporting unit 71 is provided with a vacuum suction mechanism for vacuum suctioning the preform 2 to the insertion core 72 so that the preform 2 supported on the insertion core 72 does not come off. Instead of the vacuum suction mechanism, the insertion core 72 may be a split core that can be opened and closed, and a core opening / closing mechanism that expands the split core and presses it against the inner peripheral surface of the mouth portion 2b of the preform 2 may be provided.

(Stretching blow molding equipment)
FIG. 4 is a schematic configuration diagram showing a stretch blow molding apparatus 5. The stretch blow molding apparatus 5 is a molding unit 51 having a structure in which 24 stretch blow molding dies 52 are arranged in a vertical posture opened upward, and 24 sets corresponding to each of the stretch blow molding dies 52. The upper unit 54 provided with the stretching blow mechanism 53 and the molding unit moving mechanism 55 for moving the molding unit 51 to the preform insertion position 5A and the stretching blow position 5B (see FIGS. 1A and 1B) are provided. I have. Each of the stretch blow mechanisms 53 of the upper unit 54 includes a stretch rod 56 for performing stretch blow molding on the preform 2 inserted into each of the stretch blow molding dies 52, and a nozzle 57 for blowing air. Further, the upper unit 54 is provided with a stretching rod 56, an elevating mechanism 58 for the nozzle 57, and the like.

As shown in FIGS. 2 (C1) and 2 (C2), the molding die unit 51 includes four rows in which six stretch blow molding dies 52 are arranged at a constant pitch. The stretch blow molding die 52 is a split die, and can be opened horizontally so that the stretch blow molded resin container 3 can be dropped onto the lower container recovery section 9 by its own weight.

When the preform carrying unit 71 of the preform transfer device 7 is moved to the preform insertion position 5A in a state where the molding unit 51 is positioned at the preform insertion position 5A, the pushes carried on each of the insertion cores 72 are carried. The reform 2 is inserted coaxially from the upper end opening of each cavity of the stretch blow molding die 52 located on the lower side. When the molding unit 51 into which the preform 2 is inserted moves to the stretching blow position 5B, each of the stretching blow mechanisms 53 of the upper unit 54 is coaxial with each of the upper end openings of the cavity of the stretching blow molding mold 52 from above. Face each other. When the upper unit 54 is lowered, each cavity of the stretch blow molding die 52 and the mouth portion 2b of the inserted preform 2 are closed, and the flange 2c is between the stretch blow mechanism 53 and the upper surface of the stretch blow molding die 52. Is gripped by. In this state, the stretching rod 56 descends and the compressed air is blown to the preform 2. The preform 2 is biaxially stretched and blown to form the resin container 3. After that, the stretch blow molding die 52 is opened to the left and right, and the resin container 3 falls due to its own weight and is collected by the container collection section 9 located below.

(Operation example of preform transfer device and operation example of stretch blow molding device)
5 (A) to 5 (E) are explanatory views showing the preform transfer operation by the preform transfer device 7 and the movement of the stretch blow molding die 52 in the stretch blow molding device 5. As shown by the arrow a1 in FIG. 5A, the preform carrying unit 71 moves from the standby position 7A to the preform taking out position 7B shown by the imaginary line. When the preform take-out position 7B is reached, the 24 insertion cores 72 of the preform carrying unit 71 are supported on each of the 24 temperature control pots 62 of the temperature control unit 61 waiting at the preform take-out position 6B. It is coaxially inserted into the mouth portion 2b of the preform 2. On the side of the temperature control pot 62, the vacuum suction of the preform 2 is stopped, and instead, the vacuum suction of the preform 2 is started on the side of the insertion core 72. As a result, the preform 2 is delivered to the 24 insertion cores 72 of the preform carrying unit 71.

The preform carrying unit 71 carrying 24 preforms 2 returns to the standby position 7A. As shown in FIG. 5B, the preform carrier unit 71 is swiveled 90 degrees by the swivel mechanism 75 so as to be in the position 7C of the downward horizontal posture, and the preform 2 is vertically rotated from each insertion core 72. It will be in a suspended state. In parallel with the operation of the preform supporting unit 71, the molding unit 51 of the stretch blow molding apparatus 5 moves from the stretch blow position 5B to the preform insertion position 5A. The preform insertion position 5A is a position directly below the preform carrying unit 71 at the position 7C. After that, as shown in FIG. 5C, when the preform supporting unit 71 is lowered by the elevating mechanism 76, the preform 2 is coaxially inserted into each stretch blow molding die 52. The vacuum suction of the preform 2 by the insertion core 72 is stopped. As a result, the preforms 2 of the stretch blow molding dies 52 waiting at the preform insertion position 5A are coaxially inserted.

Next, as shown in FIG. 5D, the preform carrying unit 71 rises to position 7C, then turns 90 degrees and returns to the forward-facing vertical posture standby position 7A. The molding unit 51 into which the preform 2 is inserted returns to the stretching blow position 5B. At the stretching blow position 5B, the stretching blow mechanism 53 of the upper unit 54 is lowered, and the preform 2 is biaxially stretched and blown to form the resin container 3. After that, the stretch blow mechanism 53 rises, and as shown in FIG. 5 (E), the stretch blow molding die 52 opens, and the resin container 3 falls and is collected by the lower container collection unit 9. After closing the mold, the molding unit 51 moves to the preform insertion position 5A and stands by at this position.

(Operation example of manufacturing system)
In the manufacturing system 1 configured in this way, each part is driven and controlled by the control device 8 to manufacture a series of resin containers. An example of the manufacturing operation of the resin container 3 by the manufacturing system 1 will be described below.

6A and 6B are flowcharts showing an example of the operation of the manufacturing system 1. In these figures, the preform is labeled as "PF". In the injection molding step S (4) in the injection molding apparatus 4 of the manufacturing system 1, the injection molding apparatus 4 is switched from the mold opening state to the mold clamping state, the molding resin is injected, and 24 preforms 2 are injection molded at the same time. Will be done. The preform 2 is cooled to a temperature lower than the glass transition temperature by the injection molding mold 40, then released from the female mold 43, moves to the mold opening position 4B together with the male mold 44, and stops.

In the temperature control step S (6) of the temperature control device 6, the temperature control unit 61 of the temperature control device 6 waiting at the preform take-out position 6B after the mold of the injection molding die 40 is opened is the preform acceptance position 6A. Move to. At the preform receiving position 6A, each of the 24 temperature control pots 62 faces coaxially with each preform 2 of the 24 male molds 44. The preform 2 is extruded from the male mold 44 and released from the mold. At the same time, the inside of each of the temperature control pots 62 is evacuated. Each of the preforms 2 is extruded from each of the male molds 44 and accepted into each of the temperature control pots 62. The temperature control unit 61 carrying 24 preforms 2 moves from the preform receiving position 6A to the preform taking-out position 6B. The temperature control unit 61 stands by at the preform take-out position 6B until the mold opening in the next injection molding step is performed.

In the temperature control pot 62, while the preform 2 is contained, the temperature adjustment operation of heating the preform 2 to bring it to the optimum temperature state for stretch blow molding is continuously performed. That is, the outer peripheral surface of the preform 2 is in surface contact with the inner peripheral surface of each temperature control pot 62. Around the temperature control pot 62, for example, a heat medium adjusted to a range of 130 ° C. or lower above the glass transition point circulates. Therefore, the preform 2 is heated, and the temperature is adjusted from the temperature state below the glass transition point to the optimum temperature state for stretch blow molding. During the temperature rise adjustment, the distortion of injection molding remaining in the preform 2 is also removed, and all 24 preforms are temperature-controlled to the same temperature, so that the preforms having the same history are stretched. In the blow molding mold 52, all are uniformly molded products.

Explaining with reference to FIG. 6A, in the first injection molding step in which all the temperature control pots 62 are empty, the temperature control unit 61 receives the preform from the preform take-out position 6B which is the standby position. Moving to position 6A, the first temperature control pot group 62 (1) is positioned at the preform receiving position 6A. After receiving the preform 2 in the 24 temperature control pots 62 of the first temperature control pot group 62 (1), the temperature control unit 61 returns from the preform acceptance position 6A to the preform take-out position 6B, and is the second. The temperature control pot group 62 (2) stands by in a state of being positioned at the preform take-out position 6B.

In the second injection molding step, the temperature control unit 61 moves from the preform take-out position 6B toward the preform receiving position 6A, and the second temperature control pot group 62 (2) is moved to the preform receiving position 6A. Position to. Each of the 24 newly injection-molded preforms 2 is received in each of the 24 temperature control pots 62 belonging to the second temperature control pot group 62 (2). The temperature control unit 61 returns from the preform receiving position 6A to the preform take-out position 6B, and stands by in a state where the third temperature control pot group 62 (3) is positioned at the preform take-out position 6B.

In the third injection molding operation, the temperature control unit 61 moves from the preform take-out position 6B toward the preform receiving position 6A, and the third temperature control pot group 62 (3) is moved to the preform receiving position 6A. Position to. Each of the 24 newly injection-molded preforms 2 is received in each of the 24 temperature control pots 62 belonging to the third temperature control pot group 62 (3). The temperature control unit 61 returns from the preform receiving position 6A to the preform take-out position 6B, and stands by in a state where the first temperature control pot group 62 (1) is positioned at the preform take-out position 6B.

At the time after the third injection molding process, the preform 2 is filled in all 72 temperature control pots 62. At this point, in the first temperature control pot group 62 (1), the temperature adjustment of the 24 preforms 2 is performed over two injection molding steps, and the second temperature control pot group 62 (2). ), The temperature of the 24 preforms 2 is adjusted over one injection molding step.

In each injection molding step from the fourth time onward, as shown in FIG. 6B, 24 preforms 2 whose temperature has been adjusted over the two injection molding steps are taken out from the temperature control unit 61. , The preform transfer step S (7) inserted into the stretch blow molding die 52, and the stretch blow molding step S (5) in which the preform 2 is biaxially stretched and blown in the stretch blow molding die 52 to form a resin container. Is performed in parallel with the injection molding step S (4) and the temperature control step S (6).

At the time when the fourth injection molding process is started, 24 preforms 2 are used for the second and third times in the first temperature control pot group 62 (1) of the temperature control unit 61. The temperature has been adjusted during the injection molding process. When the fourth injection molding step is started, the preform 2 is taken out from the 24 temperature control pots 62 of the first temperature control pot group 62 (1) positioned at the preform take-out position 6B, and the preform 2 is taken out. The temperature control pot 62 of the 1 temperature control pot group 62 (1) becomes empty. When the mold of the injection molding apparatus 4 is opened, the temperature control unit 61 is moved to the preform receiving position 6A, the first temperature control pot group 62 (1) is positioned at the preform receiving position 6A, and the first temperature control is performed. The newly injection-molded preform 2 is accepted in the temperature control pot 62 of the pot group 62 (1). The temperature control unit 61 returns from the preform receiving position 6A to the preform take-out position 6B as in the first case, and the second temperature control pot group 62 (2) is positioned at the preform take-out position 6B. stand by.

At the time when the fifth injection molding process is started, in the second temperature control pot group 62 (2) of the temperature control unit 61, 24 preforms 2 are used for the third and fourth times. The temperature has been adjusted during the injection molding process. In the fifth injection molding step, the preform 2 is taken out from the temperature control pot 62 of the second temperature control pot group 62 (2) positioned at the preform take-out position 6B by the preform transfer device 7, and the preform 2 is taken out. The 24 temperature control pots 62 of the 2 temperature control pot group 62 (2) are emptied. After that, when the mold of the injection molding apparatus 4 is opened as in the second case, the temperature control unit 61 moves from the preform take-out position 6B to the preform receiving position 6A, and the second temperature control pot Group 62 (2) is positioned at the preform receiving position 6A, and 24 preforms 2 are carried in the temperature control pot 62 of the second temperature control pot group 62 (2). The temperature control unit 61 returns from the preform receiving position 6A to the preform take-out position 6B, and stands by in a state where the third temperature control pot group 62 (3) is positioned at the preform take-out position 6B.

At the time when the sixth injection molding process is started, 24 preforms 2 are used for the fourth and fifth times in the third temperature control pot group 62 (3) of the temperature control unit 61. The temperature has been adjusted during the injection molding process. In the sixth injection molding step, the preform 2 is taken out from the temperature control pot 62 of the third temperature control pot group 62 (3) positioned at the preform take-out position 6B by the preform transfer device 7, and the preform 2 is taken out. The 24 temperature control pots 62 of the 3 temperature control pot group 62 (3) are emptied. After that, as in the case of the third time, when the mold opening of the injection molding apparatus 4 is performed, the temperature control unit 61 moves from the preform take-out position 6B to the preform receiving position 6A, and the third temperature control pot Group 62 (3) is positioned at the preform receiving position 6A, and 24 preforms 2 are carried in the temperature control pot 62 of the third temperature control pot group 62 (3). The temperature control unit 61 returns from the preform receiving position 6A to the preform take-out position 6B, and stands by in a state where the first temperature control pot group 62 (1) is positioned at the preform take-out position 6B.

In the seventh and subsequent injection molding steps, the above-mentioned fourth to sixth injection forming steps are repeated, and 24 resin containers 3 are manufactured. In the temperature control unit 61, the 24 preforms 2 whose temperature has been adjusted over the two injection molding steps are sequentially taken out and transferred to the stretch blow molding apparatus 5.

As described above, in the manufacturing system 1, 24 preforms 2 whose temperature has been adjusted over two injection molding steps are taken out from the temperature control pot 62 for each injection molding step. Then, it is transferred to the stretch blow molding apparatus 5 and biaxially stretch blow molded to obtain the resin container 3. The temperature adjustment time of the preform 2 can be secured without being restricted by the time of one injection molding process in the injection molding apparatus 4. Further, it is possible to secure a sufficient adjustment time for adjusting the preform 2 to a temperature state suitable for blow molding without lowering the production efficiency.

Therefore, the residual temperature of the preform 2 after injection molding and the injection residual strain can be eliminated, and the non-uniform distribution of the container wall thickness at the time of stretch blow molding due to the variation in the residual temperature can be made uniform. For example, even when a resin container is manufactured from a thick preform or a preform having a large variation in wall thickness, each part of the preform is uniformly heated to a temperature state suitable for stretch blow molding. Then, it can be transferred to the stretch blow molding process.

Here, if the temperature of the preform 2 can be adjusted in the time of one injection molding step, for example, 48 pieces of the first and second temperature control pot groups 62 (1) and 62 (2). Only the temperature control pot 62 needs to be used. In each injection molding process, 24 preforms 2 are transferred from the first temperature control pot group 62 (1) to the stretch blow molding apparatus 5, and newly added to the empty first temperature control pot group 62 (1). The operation of accepting the injection-molded 24 preforms 2 and the second temperature control that was emptied by transferring the 24 preforms 2 from the second temperature control pot group 62 (2) to the draw blow molding apparatus 5. The operation of accepting the 24 newly injection-molded preforms 2 in the pot group 62 (2) may be alternately performed.

Further, the number of temperature control pots 62 of the temperature control unit 61 can be increased. For example, the first temperature control pot group to the Mth temperature control pot group (M is an integer of 4 or more) are arranged in the temperature control pot 62. The number of temperature control pots belonging to each temperature control pot group shall be at least the same as the number of preforms 2 injected and molded at the same time. As a result, the temperature adjustment time of the preform 2 can be set to the time for (M-1) injection molding steps.

In this example, 24 pieces of preform 2 are injection-molded to manufacture 24 pieces of resin container 3. Of course, the number of preforms 2 simultaneously molded is not limited to 24. Assuming that the number of preforms 2 simultaneously molded is L (L is an integer of 2 or more), the number of temperature control pots 62 belonging to each temperature control pot group of the temperature control device 6 may be at least L. ..

Next, in the manufacturing system 1 of this example, the resin container 3 is manufactured from the preform 2 having a shape in which the mouth portion 2b does not have a screw portion. Unlike a preform for manufacturing a normal PET bottle or the like, it is difficult to use a mechanism for gripping and transferring a mouth portion with a threaded portion from the outer peripheral side. In this example, the temperature control pot 62 of the temperature control unit 61 is faced coaxially from the horizontal direction with respect to the preform 2 that is biting into the male mold 44 after the mold is opened in the injection molding mold 40, and the male mold 44 is used. The ejected preform 2 is received in the temperature control pot 62 and evacuated to be brought into close contact with the inner surface of the temperature control pot 62. Further, by inserting the insertion core 72 into the mouth portion 2b of the preform 2 inserted in the temperature control pot 62 and sucking the vacuum, the preform 2 is taken out from the temperature control pot 62 and put into the stretch blow molding apparatus 5. I'm transferring. It is possible to reliably transfer the preform 2 provided with the mouth portion 2b with the flange 2c without the screw portion.

1 Resin container manufacturing system 2 Preform 2a Cylindrical body 2b Mouth 2c Flange 3 Resin container 3a Cylindrical body 3b Mouth 3c Flanging 4 Injection molding device 4A Mold closing position 4B Mold opening position 5 Stretch blow molding device 5A Preform insertion position 5B Stretch blow position 6 Temperature control device 6A Preform acceptance position 6B Preform take-out position 7 Preform transfer device 7A Standby position 7B Position 7C Position 8 Control device 9 Container recovery unit 40 Injection molding type 43 Female type 44 Male Mold 51 Molding mold unit 52 Stretching blow Molding mold 53 Stretching blow mechanism 54 Upper unit 55 Molding mold unit Moving mechanism 56 Stretching rod 57 Nozzle 58 Elevating mechanism 61 Temperature control unit 61a Front side 62 Temperature control pot 62 (1) First temperature control pot Group 62 (2) Second temperature control pot group 62 (3) Third temperature control pot group 63 Movement mechanism 64 Circulation path 65 Suction passage 71 Preform carrying unit 72 Insertion core 73 Supporting unit Moving mechanism 75 Swing mechanism 76 Elevating mechanism S (4) Injection molding step S (5) Stretch blow molding step S (6) Temperature control step S (7) Preform transfer step

Claims (6)

Using an injection molding device, a preform made of a plurality of bottomed cylinder-shaped or cup-shaped thermoplastic resins is injection-molded at the same time, and the preform is cooled to below the glass transition point of the thermoplastic resin from the injection molding die. Injection molding process to take out and
A plurality of the preforms taken out from the injection molding die are received in the temperature control pot of the temperature control device, and the temperature is adjusted so that the preforms can be blow-molded in the temperature control pot. Preparation process and
The preform transfer device takes out a plurality of the preforms in a temperature state capable of blow molding from the temperature control pot, transfers the taken out preforms to the blow molding device, and a plurality of blow molding dies of the blow molding device. And the transfer process to insert into
In a method for manufacturing a resin container, which comprises a blow molding step of forming a plurality of resin containers by performing blow molding or stretch blow molding on each of the preforms in the blow molding mold of the blow molding apparatus.
When N is an integer of 2 or more in a temperature control pot group having a number of the temperature control pots capable of accepting a plurality of the preforms to be injection-molded at the same time in the injection molding mold, the temperature control device can be used. Arrange N sets and
When the empty temperature control pot group that does not contain the preform is defined as an empty temperature control pot group,
Until the injection molding process is performed a plurality of times of N times or less.
The temperature control step is performed in parallel each time the injection molding step is performed without performing the transfer step and the blow molding step, and the injection-molded preform is put into one set of the empty temperature control pots. Accept each of the temperature control pots to which the temperature control pot belongs and start the temperature adjustment.
After performing the injection molding step a plurality of times,
Each time the injection molding step is performed, the transfer step, the blow molding step, and the temperature control step are performed in parallel.
The temperature control pot group containing the preform injection-molded in the injection molding step performed at the earliest time is set as the temperature control pot group to be taken out from the preform.
In the transfer step, the preform is taken out from each of the temperature control pots belonging to the temperature control pot group to be taken out from the preform, transferred to the blow molding apparatus, inserted into the blow molding mold, and inserted into the blow molding mold.
In the blow molding step, the preform inserted in the blow molding mold is blow molded or stretch blow molded to form a plurality of the resin containers.
In the temperature control step, the resin container is characterized in that the injection-molded preform is received in each of the temperature control pots belonging to the set of empty temperature control pots and the temperature control is started. Production method. In claim 1,
Until the injection molding step is performed N times, the transfer step and the blow molding step are not performed, and the temperature control step is performed in parallel each time the injection molding step is performed.
A method for manufacturing a resin container in which the transfer step, the blow molding step, and the temperature control step are performed in parallel each time the injection molding step is performed after the injection molding step is performed N times. In claim 1,
In the blow molding apparatus, a plurality of the blow molding dies are arranged at a predetermined arrangement pitch.
In the injection molding die of the injection molding apparatus, a pair of a male mold and a female mold defining an injection molding cavity for injection molding the preform are arranged at the same pitch as the arrangement pitch.
In each of the temperature control pot groups of the temperature control device, the temperature control pots are arranged at the same pitch as the arrangement pitch.
The preform transfer device includes a plurality of insertion cores that can be inserted into the mouth of the preform, and the insertion cores are arranged at the same pitch as the arrangement pitch. A method for manufacturing a resin container. In claim 3,
In the step of receiving the preform from the injection molding mold into the temperature control pot in the temperature control step,
In the injection molding device, each of the temperature control pots is coaxially confronted with each of the preforms attached to the male mold in the mold open state.
The preform ejected from the male mold is vacuum-sucked and accepted into the temperature control pot so that the outer surface of the preform is in close contact with the inner surface of the temperature control pot.
In the step of taking out the preform from the temperature control pot in the transfer step,
The insertion core of the preform transfer device is coaxially inserted into the mouth of the preform contained in each of the temperature control pots belonging to the temperature control pot group to be taken out.
The vacuum suction of the preform in the temperature control pot is released so that the preform can be delivered to the insertion core coaxially inserted into the mouth of the preform.
The preform is vacuum-sucked into the insertion core inserted into the mouth of the preform, or the insertion core is expanded to mechanically engage the insertion core with the inner peripheral surface of the mouth. A method for manufacturing a resin container in which the preform is supported on the insertion core. In claim 4,
In the step of inserting the preform supported on the insertion core into the plurality of blow molding dies in the transfer step,
Each of the insertion cores is positioned coaxially with respect to each of the blow-molded cavities.
The preform carried on each of the insertion cores is coaxially inserted into each of the blow-molded cavities.
A method for manufacturing a resin container in which the vacuum suction or mechanical engagement is released, the preform is removed from the insertion core, and the resin container is delivered to the blow molding mold. In claim 5,
The preform has a shape in which a mouth portion having a flange is provided at the upper end of a bottomed tubular or cup-shaped body portion and no screw portion is provided on the outer periphery of the mouth portion.
In the blow molding step, a method for manufacturing a resin container in which blow molding or stretch blow molding is performed only on the body portion of the preform to form the resin container in which the flange and the mouth portion remain as they are.

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