JPWO2019163889A1 - Resin container manufacturing method and blow molding equipment - Google Patents

Abstract

A method for manufacturing a resin container for molding a resin container 10 from a preform 12, wherein the preform 12 is blown with both gas and liquid 30 to form the container 10, and the inside of the container 10. A method for producing a resin container, which comprises a waste liquid step of draining the liquid 30 remaining in the container, and the amount of the liquid 30 used in the blow step is smaller than the filling capacity of the container 10.

Description

The present invention relates to a method for manufacturing a resin container and a blow molding apparatus.

Compressed air is usually used as the pressure medium for blow molding because of its high convenience. For example, Patent Document 1 discloses a blow molding method using compressed air. Further, in recent years, a method has been devised in which a blow molding step and a filling step are performed in a single step by using a liquid to be filled in a container as a pressure medium (Patent Document 2).

Japanese Patent Application Laid-Open No. 2006-264035 Japanese Patent Application Laid-Open No. 2015-066921

In blow molding using compressed air, high pressure air compressed by a compressor is blown into the preform in order to shape the preform into a desired container shape. However, if the pressure of the compressed air and its control are insufficient, or if sufficient blow time is not secured, the shaping from the preform to the container is insufficient, coupled with the shrinkage of the container that occurs after molding. There is a risk of becoming. For example, the wall thickness distribution of the container is not appropriate, and the uneven portions (ribs, patterns, markings, characters, etc.) on the surface of the container are not clear. Further, in blow molding with compressed air, molding defects (poor appearance) due to uneven elongation such as tear patterns and ring patterns tend to occur in the container after blowing. Compressed air has a lower thermal conductivity than liquid, and even if compressed air comes into contact with the inner wall surface of a preform having an unbalanced temperature, the unbalanced temperature is maintained without being reduced. Only the high temperature region of the preform is locally stretched by compressed air to cause a state of first contact with the mold, and the blown preform is cooled unevenly. Due to this, appearance defects such as tear patterns and ring patterns occur. In order to prevent such appearance defects, it is necessary to optimally adjust the molding conditions such as the temperature distribution of the preform and the introduction timing of the compressed air, which is difficult.

Further, it is necessary to cool the preform for a certain period of time after blowing it into the shape of a container, and the blowing process takes a certain amount of time. In particular, when molding a container with improved heat resistance, a process of blowing the preform into the shape of the container with compressed air and then circulating the cooling air into the container is also required, and the blowing process takes longer. Become. At the same time, the operating rate and energy consumption of the compressor will also increase.

The present invention provides a method for producing a resin container, which has excellent shapeability, can suppress appearance defects (molding defects) that occur when blowing with a compressed gas, and can shorten the time of the blowing process. It is an object of the present invention to provide a blow molding apparatus.

The method for manufacturing a resin container of the present invention that can solve the above problems is
It is a method of manufacturing a resin container that molds a resin container from a preform.
A blowing step of blowing the preform with both gas and liquid to form the container,
A waste liquid process for draining the liquid remaining inside the container, and
Including
The amount of the liquid used in the blowing step is less than the filling capacity of the container.

According to the manufacturing method, by blowing the gas and the liquid in an amount smaller than the filling capacity of the container into the preform, it becomes easy to shape the preform into a desired container shape, and also in the blowing step. You can save time.

The method for manufacturing a resin container of the present invention is
In the blow process
The gas and the liquid are introduced into the preform from a blow nozzle connected to a supply path that supplies the gas and the liquid.
The supply path is provided with a storage area for the gas.
It is preferable that the liquid blows the preform together with the gas via the storage region by applying pressure to the liquid.

According to the above configuration, the preform can be blown with gas and liquid by the pressure applied to the liquid. Further, since the pressure reference of the pressurizing medium is a liquid whose pressure is increased by a pump or the like, the specification requirement of the compressor for compressing the gas can be reduced. That is, the type of compressor may be either a low pressure type or a high pressure type.

The method for manufacturing a resin container of the present invention is
In the blow process
The gas and the liquid are introduced into the preform from a blow nozzle connected to a supply path that supplies the gas and the liquid.
The supply path is provided with a storage area for the liquid.
It is preferable that the pressure is applied to the gas so that the gas blows the preform together with the gas via the storage region.

According to the above configuration, the preform can be blown with a gas and a liquid by the pressure applied to the gas, and the container can be blow-molded without using a device for applying pressure to the liquid. Further, since a liquid having excellent formability is used, the preform can be blown into a container having a desired shape by using either a high-pressure gas or a low-pressure gas, and the apparatus can be simplified.

The method for manufacturing a resin container of the present invention is
In the blow process
The gas and the liquid are introduced into the preform from a blow nozzle connected to a supply path for supplying the gas and the liquid by applying pressure to the gas and the liquid, and blow the preform. , And preferred.

According to the above configuration, the preform can be blown by the gas and the liquid by the pressure applied to the gas and the pressure applied to the liquid, and the pressure related to the blow molding condition of the preform can be finely controlled. .. Further, since pressure is applied to the liquid and the gas, it is possible to blow the preform into a container having a desired shape without applying the high pressure adopted in normal blow molding to the gas. Further, the pressure medium introduced into the preform is a mixture of a liquid and a gas, and a synergistic effect can be expected as compared with the case where only the liquid or the gas is used.

Further, the blow molding apparatus of the present invention capable of solving the above problems is
An injection molding unit that manufactures resin-made bottomed preforms,
A blow molding unit for manufacturing a container by blow molding a preform manufactured by the injection molding unit is provided.
The blow molding unit is
The mold on which the preform is placed and
The storage part where the liquid is stored and
A supply path for supplying the compressed gas and the liquid into the preform arranged in the mold, and
A control unit that controls the supply pressure of at least one of the compressed gas and the liquid supplied into the preform via the supply path for blow molding.
Have.

According to the molding apparatus having the above configuration, the preform can be blown by the compressed gas and the liquid by having a storage portion in which the liquid is stored and a supply path for supplying the compressed gas and the liquid. As a result, it becomes easy to shape the preform into a desired container shape, and the time of the blowing step can be shortened. Further, by providing a control unit that controls the supply pressure of at least one of the compressed gas and the liquid, the compressed gas and the liquid can be blown to the preform by applying pressure to at least one of the compressed gas and the liquid.

Further, the blow molding apparatus of the present invention is
The blow molding unit further has a generation unit capable of generating the compressed gas.
In the supply path, the liquid is stored at a position closer to the preform than the compressed gas.
It is preferable that the control unit can adjust the blow pressure of the liquid supplied into the preform by controlling the supply pressure of the compressed gas.

According to the above configuration, the preform can be blown with gas and liquid by the pressure applied to the gas, and the container can be blow-molded without using a device for applying pressure to the liquid. Further, since a liquid having excellent formability is used, the preform can be blown into a container having a desired shape even if a low-pressure gas is used, and the generation part of the compressed gas can be simplified.

According to the present invention, it is possible to manufacture a resin container which is excellent in shapeability, can suppress appearance defects (molding defects) that occur when blown with a compressed gas, and can shorten the time of the blowing process. Methods and blow molding equipment can be provided.

It is a block diagram of the blow molding apparatus which concerns on embodiment. It is a schematic diagram which shows the state of the blow molding of the 1st to 3rd Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 1st Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 1st Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 1st Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 1st Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 2nd Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 3rd Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 4th Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 4th Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 5th Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the state of the blow molding of the 5th Embodiment which manufactures a container from a preform in a blow molding unit. It is a schematic diagram which shows the outline of the blow molding unit of 6th Embodiment. It is a schematic diagram which shows the outline of the blow molding unit of 7th Embodiment.

(First Embodiment)
Hereinafter, an example of the embodiment of the present invention (first embodiment) will be described with reference to the drawings. The dimensions of each member shown in this drawing may differ from the actual dimensions of each member for convenience of explanation. First, the blow molding apparatus 20 for manufacturing the resin container 10 will be described with reference to FIG. FIG. 1 is a block diagram of the blow molding apparatus 20.

As shown in FIG. 1, the blow molding apparatus 20 includes an injection molding unit 22 for manufacturing the preform 12. An injection device 24 for supplying a resin material as a raw material is connected to the injection molding unit 22. Further, the blow molding apparatus 20 includes a blow molding unit 200 for blowing the preform 12 to manufacture the container 10. That is, the blow molding apparatus 20 includes at least an injection molding unit 22 and a blow molding unit 200 as a molding station. Further, the blow molding apparatus 20 may further include, as an additional molding station, a temperature control unit for adjusting the temperature distribution of the preform 12 before blow molding and a take-out unit for discharging the container 10 to the outside of the apparatus. That is, the configuration of the blow molding apparatus 20 includes (1) an injection molding unit 22 and a blow molding unit 200, (2) an injection molding unit 22, a blow molding unit 200 and a take-out unit, and (3) an injection unit 22 and a temperature control unit. It may be any of four patterns of blow molding unit 200, (4) injection molding unit 22, temperature control unit, blow molding unit 200 and take-out unit (each unit of these patterns is in the order of molding process (FIG. 1). It is usually arranged in the order of the direction of the arrows).

The injection molding unit 22 and the blow molding unit 200 are provided at positions rotated by a predetermined angle (180 degrees in the present embodiment (pattern (1))) about the transport means 28. The transport means is composed of a rotating plate or the like, so that the preform 12 or the container 10 in a state where the neck portion is supported by the neck mold attached to the rotating plate is conveyed as the rotating plate rotates. It is configured. In the patterns (2) and (3), each unit is usually arranged at a position rotated 120 degrees around the conveying means 28, and in the pattern (4), each unit is usually arranged at a position rotated 90 degrees around the conveying means 28. Will be done.

The injection molding unit 22 shown in FIG. 1 includes an injection cavity type, an injection core type, a neck type, and the like (not shown). The bottomed preform 12 is manufactured by pouring a resin material from the injection device 24 into the preform-shaped space formed by molding these molds.

The blow molding unit 200 is configured to blow mold the preform 12 manufactured by the injection molding unit 22 to manufacture the container 10. Although not essential, when the temperature control unit is provided, the preform 12 is temperature-controlled before being conveyed to the blow molding unit 200. Here, the blow molding unit 200 will be described in detail with reference to FIGS. 2 to 6.

2 to 6 are schematic views showing a state of blow molding in which the container 10 is manufactured from the preform 12 in the blow molding unit 200. Details of each stage of FIGS. 2 to 6 will be described later. The blow molding unit 200 includes a mold 202 on which the preform 12 is arranged, a drawing rod 204 for stretching the preform 12 arranged at the time of blowing, and a liquid 30 as a pressurizing medium. Inside the preform 12 via the storage section 206 to be stored, the supply path 208 for supplying the compressed gas and the liquid 30 into the preform 12 arranged in the mold 202, and the supply path 208 for blow molding. It has a control unit 210 composed of a processor that controls at least one supply pressure of the compressed gas and the liquid 30 supplied to the liquid.

In the present embodiment, the function of the processor can be realized by a general-purpose microprocessor that operates in cooperation with a general-purpose memory. Examples of general-purpose microprocessors include CPUs, MPUs, and GPUs. ROM and RAM can be exemplified as the general-purpose memory. Further, the function of the processor may be realized by a dedicated integrated circuit such as a microcontroller, ASIC, and FPGA. The processor may be realized by a combination of a general-purpose microprocessor and a dedicated integrated circuit.

Further, the blow molding unit 200 has a generation unit 212 such as a compressor capable of generating a compressed gas, and a liquid supply unit 214 such as a hydraulic pump capable of supplying the liquid 30. The control unit 210 is connected to the generation unit 212 and the liquid supply unit 214. The generation unit 212 and the liquid supply unit 214 are connected to the supply path 208, and the control unit 210 controls the supply pressure of at least one of the compressed gas and the liquid 30. In this embodiment, the control unit 210 supplies at least one of the generation unit 212 and the liquid supply unit 214 based on an operation signal input by the operator to an input interface such as an operation panel provided in the blow molding apparatus 20. The process of controlling the pressure may be repeatedly executed. The storage unit 206 is provided in the middle of the supply path 208, and is configured to be partitioned by a plurality of valves (four in FIGS. 2 to 6).

Of these four valves, the first valve 220A is for adjusting the supply of the liquid 30 from the liquid supply unit 214 to the storage unit 206 by opening and closing. The second valve 220B is for adjusting the supply of gas from the generation unit 212 to the storage unit 206 by opening and closing. The third valve 220C is for depressurizing the storage unit 206 when supplying the liquid 30 to the storage unit 206. The fourth valve 220D is for adjusting the supply of the liquid 30 and the compressed gas from the reservoir 206 to the preform 12 by opening and closing. A part of the supply path 208 (hereinafter, referred to as the nozzle supply path 216) arranged at a position close to the mold 202 with respect to the fourth valve 220D is connected to the blow nozzle 218. Further, the nozzle supply path 216 is provided with a fifth valve 220E, which is an exhaust valve.

Subsequently, a method for manufacturing the container 10 will be described. The container 10 (see FIG. 6) has a blow step of blowing the preform 12 manufactured by the injection molding unit 22 with both gas and liquid 30 to form the container 10, and waste liquid 30 remaining inside the container 10. It is manufactured through a waste liquid process.

Here, the blowing process will be described with reference to FIGS. 2 to 6. FIG. 2 is a diagram showing a state in which the preform 12 is arranged in the mold 202 of the blow molding unit 200, the drawing rod 204 is arranged inside the preform 12, and the liquid 30 is stored in the storage portion 206. The preform 12 is manufactured by the injection molding unit 22 shown in FIG. 1, and is arranged in the mold 202 of the blow molding unit 200 by the conveying means 28. After the preform 12 is placed in the mold 202, the extension rod 204 is placed so as to contact the bottom of the preform 12. The liquid 30 is supplied from the liquid supply unit 214 to the storage unit 206. At this time, the first valve 220A is opened to introduce the liquid 30 into the storage unit 206, and if necessary, the third valve 220C is opened to release the pressure of the storage unit 206. When a predetermined amount of liquid 30 is introduced, the first valve 220A and the third valve 220C are closed. As a result, the blow molding unit 200 is in the state shown in FIG. Here, the liquid 30 stored in the storage unit 206 serves as a pressurizing medium for the preform 12. The amount of the liquid 30 stored in the storage unit 206 is smaller than the filling capacity or the full filling capacity of the container 10 to be manufactured. The amount of the liquid 30 stored in the storage unit 206 is about 1/5 to 4/5, preferably 1/3 to 3/4, more preferably about 1/2 of the filling capacity or full filling capacity of the container 10. It should be set to. This also applies to the subsequent embodiments.

Subsequently, the second valve 220B is opened, pressure is applied by the generation unit 212 by the control unit 210 to supply the compressed gas generated to the storage unit 206, and at the same time, the fourth valve 220D is opened to supply the storage unit 206. The compressed gas supplied from the liquid 30 and the generation unit 212 is supplied to the preform 12 (FIG. 3). At this time, the gas existing in the nozzle supply path 216 is also accompanied and supplied to the preform 12. At this time, the stretching rod 204 is stretched toward the bottom of the mold 202 to stretch the preform 12 (FIG. 4). At this time, the liquid 30 and the compressed gas are introduced into the preform 12 from the blow nozzle 218, and the preform 12 begins to be blown (formed) (FIG. 4). By supplying a predetermined compressed gas, the shaping from the preform 12 to the container 10 is completed, and the container 10 is manufactured (FIG. 5). After the container 10 is manufactured, the second valve 220B and the fourth valve 220D are closed, and the fifth valve 220E is opened to release the gas in the container 10 (FIG. 6). The blow process is carried out according to the above flow.

After the blowing step, the liquid 30 inside the manufactured container 10 is discarded (waste liquid step). The waste liquid is discharged by removing the blow nozzle 218 from the container 10 to open the mold 202, and then taking out the container 10 from the blow molding unit 200 by the transport means 28. The waste liquid may be carried out by the blow molding apparatus 20, or may be carried out after being taken out from the blow molding apparatus 20. By the above blowing step and waste liquid step, a container 10 containing no filling can be obtained. According to the above embodiment, the preform 12 can be blown by the gas and the liquid 30 by the pressure applied to the gas (the pressure of the pressure medium containing the gas and the liquid 30 is based on the pressure of the compressed gas). Can be controlled as). The pressure of the compressed gas generated at high pressure by the generation unit 212 is preferably set in the range of 1.0 MPa to 3.5 MPa, and the maximum pressure at the time of final shaping of the container 10 is at least 3.0 MPa or more. It is desirable that it is set to be. Further, the pressure of the liquid supplied from the liquid supply unit is preferably set in the range of 1.0 MPa to 5.0 MPa, and the maximum pressure at the time of final shaping of the container 10 is set to be at least 2.5 MPa or more. It is desirable (but only in embodiments where the pressure reference of the pressurizing medium is controlled by a liquid). These pressure conditions are the same in the subsequent embodiments.

By the way, in blow molding using compressed air, high-pressure air is required to shape the preform into a desired container shape, and the pressure of compressed air and its control are insufficient, or sufficient blow time is secured. If this is not done, there is a risk that the shaping from the preform to the container will be insufficient, coupled with the shrinkage phenomenon of the container that occurs after molding. Specifically, there is a risk that the thickness distribution of the container is not appropriate, and the uneven portions (ribs, patterns, markings, characters, etc.) on the surface of the container are not clear. Furthermore, in blow molding using compressed air, if the temperature distribution of the preform and various molding conditions are not adjusted fairly appropriately, the container after blowing will have uneven stretching (non-uniform stretching orientation) such as tear patterns (fish eyes) and ring patterns. ) Causes molding defects (appearance defects). In addition, it is necessary to cool the preform for a certain period of time after blowing it into the shape of a container, and the blowing process takes a certain amount of time. In particular, when molding a container with improved heat resistance, a process of circulating cooling air into the container is required even after the preform is blown into the shape of the container with compressed air, so the time required for the blowing process is also long. It will be longer. In addition, compressor utilization and energy consumption will generally be high.

According to the manufacturing method of the present embodiment, the preform 12 is blown by sharing the gas (compressible fluid) and the liquid 30 (incompressible fluid) in an amount smaller than the filling capacity or the full filling capacity of the container 10. As a result, it becomes easy to shape the preform 12 into a desired shape of the container 10, it is possible to suppress molding defects that occur when blowing with a compressed gas, and it is possible to shorten the time of the blowing step. Specifically, the preform 12 is blown to the shape of the container 10 in a short time because the blow molding with the liquid 30 having the property of incompressibility different from that of the gas is excellent in the shapeability of the container 10. Is possible. Further, since it is excellent in shapeability, even a container 10 having a complicated shape can be blow-molded in a short time.

Since the thermal conductivity of the liquid 30 is higher than that of the gas, cooling proceeds before the preform 12 comes into contact with the inner wall of the mold 202 of the blow molding unit 200, and as a result, the cooling time in the blow process is shortened and blow is performed. The process can be shortened. Further, when a thick container is blow-molded with compressed air, a longer cooling time is required, but according to the manufacturing method, the cooling time can be preferably shortened. Further, as compared with the case where only gas is used, the preform 12 is cooled uniformly, and molding defects such as uneven elongation due to the uneven temperature of the preform 12 can be suitably prevented / reduced.

The liquid 30 of the present embodiment is just one of the pressure media for blowing, not a filling medium. Blow molding with fillers seems to still have many restrictions and disadvantages. For example, the types of fillings that can be used as a pressurizing medium are limited, a mechanism that appropriately controls the amount and pressure of the filling, a mechanism that keeps the filling area clean (sterilized), a nozzle-preform As a result of the need to equip the blow molding machine with many mechanisms controlled with high precision, such as a mechanism for exhausting the gas remaining in between, the equipment cost is significantly increased. In addition, the optimum blow molding conditions are usually obtained as a result of many trials and errors, but when blowing with a filling material, the filling material may be wasted at this time.

On the other hand, since the liquid 30 used in the present embodiment is not a filling liquid, there are many types that can be used, and an inexpensive liquid that can be discarded after use can also be used. Further, the blow molding apparatus 20 only needs to basically incorporate the hydraulic circuit mechanism into the conventional pneumatic circuit mechanism, and the cost does not increase so much. That is, the blow molding apparatus 20 and the molding method capable of improving the shapeability and shortening the blow time can be achieved without making many modifications to the conventional blow molding using compressed air as a pressure medium.

As the liquid 30 used in the present embodiment, it is desirable to use the temperature-controlled liquid 30 because it is necessary to appropriately cool the preform 12 from the inside. For example, cooling water whose temperature is controlled to 10 to 30 ° C. and pressurized (tower water or chiller water usually used in a blow molding machine) can be used. If the blow molding apparatus 20 and the filling machine are to be directly connected, the cooling water may contain a disinfectant (hydrogen peroxide solution, hypochlorous acid, peracetic acid, etc.) or a cleaning agent (various rinsers, etc.). Absent. When considering the rust preventive surface of the mold 202, a liquid having low metal corrosiveness (alcohol, various organic solvents, etc.) may be used. When a relatively expensive liquid is used, it may be collected by one blow without waste liquid and used a plurality of times. The ratio of the gas and the liquid 30 used as the pressurizing medium may be appropriately changed to an optimum ratio in consideration of the temperature of the preform 12, the shape of the container 10, the stretching ratio, and the like.

Further, in blow molding using compressed air, if the compressed air contains a small amount of water, water droplets may be formed on the molded container 10, and it is considered preferable to use compressed air that does not contain water. Was being done. However, the present inventors have found that when a liquid 30 which is not a trace amount is blown to the preform 12 together with a gas as in the production method of the present embodiment, it is difficult for water droplets to be formed on the container 10. That is, according to the manufacturing method of the present embodiment, it is possible to prevent the formation of water droplet marks on the container 10.

Further, in the manufacturing method of the present embodiment, the liquid 30 used is smaller than the filling capacity of the container 10 (the total volume of the compressed air and the liquid 30 existing inside the container 10 before disposal is the filling capacity of the container 10 or full injection. (Same capacity), discarded after blow molding. In the method of shaping the preform 12 into the shape of the container 10 by the liquid 30 filled in the container 10, it is difficult to control the filling amount of the liquid 30, but in the production method of the present embodiment, any amount can be used as long as it satisfies the desired moldability. The liquid can be used in the amount of, and does not require complicated control.

Further, in the manufacturing method of the present embodiment, since the gas and the liquid 30 are blown to the preform 12 by the pressure applied to the gas, the container 10 is blow-molded without using an apparatus for applying pressure to the liquid 30. Can be done. Further, since the liquid 30 having excellent shapeability is used, the preform 12 can be blown into the container 10 having a desired shape by using either a high pressure gas or a low pressure gas, and the apparatus can be simplified.

Further, according to the molding apparatus of the present embodiment, by having the storage unit 206 in which the liquid 30 is stored and the supply path 208 for supplying the compressed gas and the liquid 30, both the compressed gas and the liquid 30 can be used. The preform 12 can be blown. As a result, it becomes easy to shape the preform 12 into a desired shape of the container 10, and the time of the blowing step can be shortened. Further, by providing a control unit 210 for controlling the supply pressure of at least one of the compressed gas and the liquid 30, the compressed gas and the liquid 30 are introduced into the preform 12 by applying pressure to at least one of the compressed gas and the liquid 30. Blow molding can be performed.

Although the configuration of the specific blow molding unit 200 has been described in the above description, the present invention is not limited to the above specific configuration. For example, as shown in Japanese Patent Application Laid-Open No. 8-230027, the preform may be designed to be arranged in the mold with the neck portion of the preform facing vertically downward. This configuration is preferable because the liquid remaining in the container can be drained smoothly.

Further, according to the blow molding apparatus 20 of the present embodiment, the preform 12 can be blown with the gas and the liquid 30 by the pressure applied to the gas (the pressure of the pressurizing medium is controlled with reference to the air pressure). The container 10 can be blow-molded without using a device for applying pressure to the liquid 30. Further, since the liquid 30 having excellent shapeability is used, the preform 12 can be blown into the container 10 having a desired shape even if a low-pressure gas is used, and the compressed gas generation unit 212 can be simplified.

(Second Embodiment)
Subsequently, another example (second embodiment) of the embodiment of the present invention will be described with reference to FIGS. 2 and 7. Since the second embodiment is the same as the first embodiment except for the aspect of the blow step, the description other than the blow step will be omitted.

In the second embodiment as well, the preform 12 is arranged in the mold 202 of the blow molding unit 200, the extension rod 204 is arranged inside the preform 12, and the storage portion 206 is arranged according to the same procedure as in the first embodiment. The liquid 30 is stored in the container (Fig. 2).

Subsequently, as shown in FIG. 7, the first valve 220A is opened, the liquid supply unit 214 applies pressure to the liquid by the control unit 210 to supply the liquid 30 to the storage unit 206, and the fourth valve is also provided. The 220D is opened to supply the liquid 30 of the reservoir 206 to the preform 12. At this time, the gas existing in the nozzle supply path 216 is also accompanied and supplied to the preform 12. The nozzle supply path 216 in this case corresponds to a gas storage region. At this time, the stretching rod 204 is stretched toward the bottom of the mold 202 to stretch the preform 12. At this time, the liquid 30 and the gas are blown from the blow nozzle 218 to the preform 12, and the preform 12 is shaped. By supplying a predetermined amount of the liquid 30, the preform 12 is shaped into the container 10. Complete and close the first valve 220A and the fourth valve 220D. After manufacturing the container 10, the fifth valve 220E is opened to release the gas in the container 10. The blow process is carried out according to the above flow.

According to the second embodiment described above, the preform 12 can be blown with the gas and the liquid 30 by the pressure applied to the liquid 30 (the pressure of the pressure medium containing the gas and the liquid 30 is the hydraulic pressure. Can be controlled with reference to). Further, since the pressure reference of the pressurizing medium is the liquid 30 whose pressure is increased by a pump or the like, the specification requirements of the compressor for compressing the gas can be relaxed, and the container 10 can be used regardless of whether the low pressure type or high pressure type compressor is used. Blow molding can be suitably performed.

(Third Embodiment)
Subsequently, another example (third embodiment) of the embodiment of the present invention will be described with reference to FIGS. 2 and 8. Since the third embodiment is the same as the first embodiment except for the aspect of the blow process, the description other than the blow process will be omitted.

In the third embodiment as well, the preform 12 is arranged in the mold 202 of the blow molding unit 200, the extension rod 204 is arranged inside the preform 12, and the storage portion 206 is arranged according to the same procedure as in the first embodiment. The liquid 30 is stored in the container (Fig. 2).

Subsequently, as shown in FIG. 8, the first valve 220A is opened, the liquid supply unit 214 applies pressure to the liquid 30 by the control unit 210 to supply the liquid 30 to the storage unit 206, and the second valve 220A is also provided. The valve 220B is opened, pressure is applied by the generation unit 212 by the control unit 210 to supply the compressed gas generated to the storage unit 206, and at the same time, the fourth valve 220D is opened to generate the liquid 30 in the storage unit 206. The compressed gas supplied from the part 212 is supplied to the preform 12. At this time, the gas existing in the nozzle supply path 216 is also accompanied and supplied to the preform 12. The nozzle supply path 216 in this case corresponds to a gas storage region. At this time, the stretching rod 204 is stretched toward the bottom of the mold 202 to stretch the preform 12. At this time, the liquid 30 and the gas are blown from the blow nozzle 218 to the preform 12, the preform 12 is shaped, and a predetermined amount of the liquid 30 and the compressed gas are supplied to the container 10 of the preform 12. The shaping is completed and the first valve 220A and the fourth valve 220D are closed. After manufacturing the container 10, the fifth valve 220E is opened to release the gas in the container 10. The blow process is carried out according to the above flow.

According to the third embodiment described above, the gas and the liquid 30 can be blown to the preform 12 by the pressure applied to the gas and the pressure applied to the liquid 30, and the pressure related to the preform 12 is fine. Control is possible. Further, since the pressure is applied to the liquid 30 and the gas, the preform 12 can be blown into the container 10 having a desired shape without applying the high pressure adopted in normal blow molding to the gas.

(Fourth Embodiment)
Subsequently, another example (fourth embodiment) of the embodiment of the present invention will be described with reference to FIGS. 9 and 10. Since the fourth embodiment is the same as the first embodiment except for the aspect of the blow process, the description other than the blow process will be omitted.

In the fourth embodiment, the preform 12 is first arranged in the mold 202 of the blow molding unit 200, the drawing rod 204 is arranged inside the preform 12, and the compressed gas is stored in the storage portion 206 (FIG. 9). ). Although the mode in which the liquid 30 is stored in the storage unit 206 has been described in the first to third embodiments, the compressed gas is stored in the storage unit 206. The preform and extension rods are arranged according to the same procedure as in the first embodiment. Compressed air is supplied from the generation unit 212 to the storage unit 206. At this time, the second valve 220B is opened to introduce the compressed gas into the storage unit 206, and if necessary, the third valve 220C is opened to release the pressure of the storage unit 206. When a predetermined amount of compressed gas is introduced, the second valve 220B and the third valve 220C are closed. As a result, the blow molding unit 200 is in the state shown in FIG. Here, the compressed gas stored in the storage unit 206 serves as a pressurizing medium for the preform 12.

Subsequently, as shown in FIG. 10, the first valve 220A is opened, the liquid supply unit 214 applies pressure to the liquid by the control unit 210 to supply the liquid 30 to the storage unit 206, and the fourth valve is also provided. The 220D is opened to supply the compressed gas of the reservoir 206 to the preform 12. At this time, the gas existing in the nozzle supply path 216 is also accompanied and supplied to the preform 12. The nozzle supply path 216 in this case corresponds to a gas storage region. The storage unit 206 corresponds to a storage area for compressed gas. At this time, the stretching rod 204 is stretched toward the bottom of the mold 202 to stretch the preform 12. At this time, the liquid 30 and the gas are blown from the blow nozzle 218 to the preform 12, and the preform 12 is shaped. By supplying a predetermined amount of the liquid 30, the preform 12 is shaped into the container 10. Complete and close the first valve 220A and the fourth valve 220D. After manufacturing the container 10, the fifth valve 220E is opened to release the gas in the container 10. The blow process is carried out according to the above flow.

According to the fourth embodiment, the preform 12 can be blown by the gas and the liquid 30 by the pressure applied to the liquid 30 (the pressure of the pressure medium containing the gas and the liquid 30 is based on the hydraulic pressure. Can be controlled as). Also in this embodiment, by blowing the gas and the liquid into the preform, it becomes easy to shape the preform into a desired container shape, and the time of the blowing step can be shortened.

(Fifth Embodiment)
Subsequently, another example (fifth embodiment) of the embodiment of the present invention will be described with reference to FIGS. 11 and 12. Since the fifth embodiment is the same as the first embodiment except for the aspect of the blow step, the description other than the blow step will be omitted.

In the fifth embodiment, the preform 12 is first arranged in the mold 202 of the blow molding unit 200, the drawing rod 204 is arranged inside the preform 12, and the liquid 30 and the compressed gas are stored in the storage portion 206. (Fig. 11). Both the liquid 30 and the compressed gas stored in the storage unit 206 are collectively referred to as a mixed fluid 40 in this embodiment. In the first to third embodiments, the mode in which the liquid 30 is stored in the storage unit 206 has been described, but in the present embodiment, the mixed fluid 40 is stored. The preform and extension rods are arranged according to the same procedure as in the first embodiment. The liquid 30 is supplied from the liquid supply unit 214 to the storage unit 206. At this time, the first valve 220A is opened to introduce the liquid 30 into the storage unit 206. Compressed air is supplied from the generation unit 212 to the storage unit 206. At this time, the second valve 220B is opened to introduce the compressed gas into the storage unit 206. If necessary, the third valve 220C is opened to release the pressure of the storage unit 206. When a predetermined amount of liquid 30 and compressed gas are introduced, the first valve 220A and the second valve 220B are closed. As a result, the blow molding unit 200 is in the state shown in FIG. Here, the mixed fluid 40 stored in the storage unit 206 contains the compressed gas and the liquid 30 and serves as a pressurizing medium for the preform 12.

Subsequently, as shown in FIG. 12, the first valve 220A is opened, the liquid supply unit 214 applies pressure to the liquid 30 by the control unit 210 to supply the liquid 30 to the storage unit 206, and the second valve 220A is also provided. The valve 220B is opened, pressure is applied by the generation unit 212 by the control unit 210 to supply the compressed gas generated to the storage unit 206, and at the same time, the fourth valve 220D is opened to supply the mixed fluid 40 of the storage unit 206. Supply to preform 12. At this time, the gas existing in the nozzle supply path 216 is also accompanied and supplied to the preform 12. The nozzle supply path 216 in this case corresponds to a gas storage region. The storage unit 206 corresponds to a storage area for the liquid 30 and the compressed gas. At this time, the stretching rod 204 is stretched toward the bottom of the mold 202 to stretch the preform 12. At this time, the liquid 30 and the compressed gas are blown from the blow nozzle 218 to the preform 12, the preform 12 is shaped, and a predetermined amount of the liquid 30 and the compressed gas are supplied to the container 10 of the preform 12. The shaping of the first valve 220A, the second valve 220B and the fourth valve 220D are closed. After manufacturing the container 10, the fifth valve 220E is opened to release the gas in the container 10. The blow process is carried out according to the above flow.

Also in this embodiment, by blowing the gas and the liquid into the preform, it becomes easy to shape the preform into a desired container shape, and the time of the blowing step can be shortened. The mixed fluid 40 may be, for example, a pressure medium in which an appropriate amount of liquid is dispersed in the gas (a pressure medium in which the liquid is scattered in a spray form in the gas). In this case, since the amount of liquid remaining in the blown container is very small, a method of simply drying with air may be adopted for the waste liquid step.

(Sixth Embodiment)
Subsequently, another example of the embodiment of the present invention (sixth embodiment) will be described with reference to FIG. FIG. 13 is a schematic view showing an outline of the blow molding unit 1200 according to the sixth embodiment. Since the configuration of the blow molding apparatus other than the blow molding unit 1200 is the same as that of the first embodiment, the description thereof will be omitted.

The blow molding unit 1200 has a liquid supply unit 1214, a generation unit 1212 for generating compressed gas, a storage unit 1206, a mold unit 1250, and a control unit (not shown). The liquid supply unit 1214 has a liquid source 1260 such as a hydraulic pump and a supply piston 1240 that holds the liquid 1030 inside. The supply piston 1240 has a rod 1242 that applies pressure to the liquid 1030 inside, and a stopper 1244 that stops the rod 1242 at a predetermined position. The generation unit 1212 that generates the compressed gas is composed of a compressor. The storage unit 1206 is a tank for storing the liquid 1030 having a volume smaller than the filling amount of the container to be molded. The mold unit 1250 has a mold, a blow nozzle, and the like that define the outer shape of the container. The control unit (not shown) is connected to the generation unit 1212 and the liquid supply unit 1214, and is configured to control the supply pressure of at least one of the compressed gas and the liquid 1030.

Next, a method of manufacturing a container using the blow molding unit 1200 will be described. The container has a blow step of blowing the preform produced by the injection molding unit 22 (see FIG. 1) with both gas and liquid 1030 to form the container, and a waste liquid step of draining the liquid 1030 remaining inside the container. Manufactured via. Since the waste liquid step is the same as that of the first embodiment, the description thereof will be omitted.

In the blowing step of the sixth embodiment, first, the liquid 1030 (for example, water) is introduced into the supply piston 1240 by the liquid source 1260, and then the rod 1242 is extended (lowered) to a position where it abuts on the stopper 1244 to reduce the liquid amount. To confirm. Next, the amount of the liquid is supplied to the storage unit 1206, and the compressed gas created by the generation unit 1212 is introduced therein so that the liquid 1030 and the compressed gas are flowed through the preform and blown. As described above, the blow process is carried out. Since the amount of liquid used in each blow process is always controlled and controlled to the same amount, the molding conditions can be made uniform between the blow batches. The pressure of the pressurizing medium can be controlled with reference to the air pressure.

(7th Embodiment)
Subsequently, another example of the embodiment of the present invention (seventh embodiment) will be described with reference to FIG. FIG. 14 is a schematic view showing an outline of the blow molding unit 2200 according to the seventh embodiment. Since the configuration of the blow molding apparatus other than the blow molding unit 2200 is the same as that of the first embodiment, the description thereof will be omitted.

The blow molding unit 2200 includes a liquid supply unit 2214, a generation unit 1212 for generating compressed gas, a merging unit 2206, a mold unit 1250, and a control unit (not shown). Here, since the generation unit 1212, the mold unit 1250, and the control unit are the same as those described in the sixth embodiment, the description thereof will be omitted. The liquid supply unit 2214 has a liquid source 1260 such as a hydraulic pump and a supply piston 2240 that holds the liquid 2030 inside. The supply piston 2240 has a rod 2242 that applies pressure to the liquid 1030 inside, and a motor 2246 connected to the rod 2242. The merging portion 2206 is a place where the high-pressure gas circuit 2208A through which the compressed gas flows and the liquid circuit 2208B through which the liquid 2030 flows meet.

Next, a method of manufacturing a container using the blow molding unit 2200 will be described. Since the manufacturing method is the same as that of the sixth embodiment except for the blowing step, the description thereof will be omitted.

In the blowing step of the seventh embodiment, a mist-like (mist-like) pressurized medium in which an appropriate amount of liquid 1030 (for example, water) is ejected into the high-pressure gas circuit 2208A and the liquid 1030 and compressed gas (for example, air) are mixed. (Mixed gas) is poured into the preform and blown. The amount of liquid to be ejected is controlled by adjusting the stroke (extension distance) of the rod 2242 with the motor 2246 so that the mixing ratio is always the same. At the same time, the motor 2246 is controlled so as to push above the gas pressure so as not to lose the gas pressure of the high-pressure gas circuit 2208A. As described above, the blow process is carried out. The pressure of the pressurizing medium can be controlled with reference to the air pressure.
Further, since the liquid 30 is used in a completely mist-like form, the amount of the liquid 30 used can be reduced as compared with the first to seventh embodiments.

Although the present invention has been described above based on the specific embodiment, the present invention is not limited to the above-described embodiment, and can be freely modified, improved, and the like as appropriate. In addition, the material, shape, size, numerical value, form, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

The blow molding apparatus 20 described in the above embodiment has an injection molding unit 22 and a blow molding unit 200, 1200, 2200, but the temperature of the preform 12 is also adjusted before blowing. It may have a temperature control part, a take-out part for taking out the manufactured container 10, and the like. However, in the manufacturing method of the present embodiment and the blow molding apparatus 20, the preform 12 is shaped by sharing the gas and liquid 30, 1030, and 2030 in the blow step, and therefore the shapeability is good. Therefore, the desired container 10 Depending on the shape of the container, the container can be suitably manufactured even in a mode in which the temperature control portion is not provided.

Further, although the specific embodiment of the supply path 208 provided with the plurality of valves has been described in the above embodiment, the embodiment of the supply path 208 is arbitrary and is not limited as long as the present invention can be achieved.

Further, in the first to fifth embodiments, an example in which the control unit 210 is connected to the generation unit 212 and the liquid supply unit 214 has been described, but the present invention is not limited thereto. The control unit 210 may be configured as a separate control unit connected to each of the generation unit 212 and the liquid supply unit 214. Further, depending on each of the first to fifth embodiments, an embodiment may include only a single control unit connected to at least one of the generation unit 212 and the liquid supply unit 214. Further, the control unit may be provided in the blow molding apparatus at a place other than the blow molding unit.

This application is based on a Japanese patent application (Japanese Patent Application No. 2018-030985) filed on February 23, 2018, and the entire application is incorporated by reference. Also, all references cited here are taken in as a whole.

10: Container, 12: Preform, 20: Blow molding device, 22: Injection molding unit, 24: Injection device, 28: Conveying means, 30, 1030: Liquid, 40: Mixed fluid, 200, 1200, 2200: Blow molding Unit, 202: Mold, 204: Stretch rod, 206, 1206: Storage unit, 208: Supply path, 210: Control unit, 212, 1212: Generation unit, 214, 1214, 2214: Liquid supply unit, 216: Nozzle supply Road, 218: Blow nozzle, 220A: 1st valve, 220B: 2nd valve, 220C: 3rd valve, 220D: 4th valve, 220E: 5th valve, 1240, 2240: Supply piston, 1242 , 2242: Rod, 1244: Stopper, 1250: Mold unit, 1260: Liquid source, 2206: Confluence, 2208A: High pressure gas circuit, 2208B: Liquid circuit, 2246: Motor

Claims (6)

It is a method of manufacturing a resin container that molds a resin container from a preform.
A blowing step of blowing the preform with both gas and liquid to form the container,
A waste liquid process for draining the liquid remaining inside the container, and
Including
A method for producing a resin container, wherein the amount of the liquid used in the blowing step is smaller than the filling capacity of the container. In the blow process
The gas and the liquid are introduced into the preform from a blow nozzle connected to a supply path that supplies the gas and the liquid.
The supply path is provided with a storage area for the gas.
The production method according to claim 1, wherein when pressure is applied to the liquid, the liquid blows the preform together with the gas via the storage region. In the blow process
The gas and the liquid are introduced into the preform from a blow nozzle connected to a supply path that supplies the gas and the liquid.
The supply path is provided with a storage area for the liquid.
The production method according to claim 1, wherein when pressure is applied to the gas, the gas blows the preform together with the liquid via the storage region. In the blow process
The gas and the liquid are introduced into the preform from a blow nozzle connected to a supply path for supplying the gas and the liquid by applying pressure to the gas and the liquid, and blow the preform. , The manufacturing method according to claim 1. An injection molding unit that manufactures resin-made bottomed preforms,
A blow molding unit for manufacturing a container by blow molding a preform manufactured by the injection molding unit is provided.
The blow molding unit is
The mold on which the preform is placed and
The storage part where the liquid is stored and
A supply path for supplying the compressed gas and the liquid into the preform arranged in the mold, and
A control unit that controls the supply pressure of at least one of the compressed gas and the liquid supplied into the preform via the supply path for blow molding.
Have,
Blow molding equipment. The blow molding unit further has a generation unit capable of generating the compressed gas.
In the supply path, the liquid is stored at a position closer to the preform than the compressed gas.
The blow molding apparatus according to claim 5, wherein the control unit can adjust the blow pressure of the liquid supplied into the preform by controlling the supply pressure of the compressed gas.

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