JP3254208B2 - Blow molding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection stretch blow molding apparatus for stretch blow molding a container from a preform having heat during injection molding, a method thereof, and a blow molding apparatus. Further, the present invention provides a method for simultaneously injection-molding N (N ≧ 2) preforms, and among them, n (1 ≦ n <).
The present invention relates to an injection stretch blow molding apparatus and a method for simultaneously blow molding n containers from N) preforms.
More specifically, the present invention relates to an injection stretch blow molding apparatus and method capable of shortening an injection molding cycle time while molding a preform while securing a sufficient cooling time, and increasing the operation rate of a blow cavity. The invention also relates to improvements in the structure and method for heating or controlling the temperature of the preform before blow molding. Further, the present invention relates to an injection stretch blow molding apparatus and a method thereof which can discharge a preform to the outside of the apparatus before transporting the preform to a blow molding section, if necessary.

[0002]

BACKGROUND OF THE INVENTION As a method of blow molding a container from a preform (parison), a method called a cold parison method or a two-stage method, and a method called a hot parison method or a one-stage method are used. There is a method. In either case, to injection mold the preform required for blow molding the container,
At least an injection cavity mold that defines the outer wall of the preform and an injection core mold that defines the inner wall of the preform are required. Furthermore, it is necessary to cool the preform to a temperature at which the preform can be released while maintaining the mold clamping state after the injection cavity mold and the injection core mold are mold-clamped and the preform is injection-molded.

[0003] In particular, in the case of the cold parison (two-stage) system, the mold release temperature of the preform must be sufficiently low, so that the injection molding cycle time increases and the production efficiency deteriorates. That is, when the injection cavity mold and the injection core mold are separated from the preform and the preform is dropped and taken out, the mold release is sufficiently low that the preform is not deformed even if it comes into contact with other members. This is because it is necessary to cool the preform to the temperature.

However, in the case of the cold parison method, since the preform molding step and the step of blow molding a container from this preform are separated, the blow molding cycle time is affected by the injection molding cycle time. There is no. However, the cold parison method is inferior to the hot parison method in terms of energy efficiency because the preform once cooled to room temperature is reheated.

On the other hand, in a hot parison (1 stage) type injection stretch blow molding machine for blow molding a bottle from a preform holding heat during injection molding, an injection molding cycle time which requires the longest time in all cycles is used. The molding cycle time of the entire apparatus is determined. Therefore, when the time required for injection molding is long, there is a problem that the throughput of the entire apparatus is reduced.

By the way, in the case of the hot parison method, the preform is released at a higher temperature than in the case of the cold parison method, but the release temperature is limited.
Injection molding cycle cannot be accelerated much. The reason for this is that, when the release temperature of the preform is high, when the injection core mold is released from the preform, the preform comes into close contact with the core mold, and a release defect called so-called winding occurs. In addition, after the injection core mold is released, there is no member that restricts the deformation of the preform, so that the preform cannot be taken out as designed due to deformation due to uneven temperature or thermal shrinkage. further,
Insufficient cooling by the injection core mold causes crystallization especially on the inner wall of the preform due to insufficient cooling, and a preform having an opaque body is taken out.

Further, when the preform is taken out before being completely cooled by the injection core mold and the injection cavity mold (in a state where the preform has a temperature capable of being blow-molded), and then blow-molded, There was such a problem.

(A) If the internal pressure (injection holding pressure) is not increased, sinks will occur on the injection cavity mold side of the preform, and a preform having a uniform temperature cannot be obtained. Therefore, when this preform is blow molded, a molded product having a uniform thickness distribution cannot be obtained.

(B) When the internal pressure (injection holding pressure) is increased, a pressure difference occurs between the gate portion and the preform end portion (for example, the neck portion), resulting in a preform having a large residual stress on the preform bottom side where the pressure is high. . Therefore, when the blow molding is performed, a molded product having a uniform thickness distribution cannot be obtained.

(C) When the preform is cooled by the injection core mold and the injection cavity mold, the preform shrinks as the cooling progresses, and moves away from the injection cavity surface. For this reason, a portion that does not contact the portion that is in contact with the injection cavity is formed on the outer peripheral wall surface of the preform, resulting in a difference in cooling rate of the preform, resulting in an uneven temperature. Therefore, when this preform is blow-molded, a molded product having a uniform thickness cannot be obtained.

As described above, in the conventional hot parison method, good blow characteristics or bottle characteristics could not be obtained unless the preform was sufficiently cooled by the injection cavity mold and the injection core mold. For this reason, the injection molding of the preform took time, and the throughput of the apparatus was reduced.

As other problems of the hot-parison-type injection stretch blow molding machine, the following various problems to be solved have occurred.

One of the problems is that when the number N of preforms to be injection-molded is increased in order to increase the throughput, cavities corresponding to the outer shapes of the same number N of bottles must be formed in the blow cavity mold. Of the molds used in the blow molding machine, the blow cavity mold is the most expensive, but this price increases almost in proportion to the number of cavities. Even with expensive dies, profitability is high if the operation rate is high, but as described above, the cycle time of the entire cavity of the blow cavity mold was not shortened because the cycle time of the entire equipment was not shortened depending on the injection molding cycle time The rate had to be low. Also, when the number of simultaneous blow molding increases, not only the number of cavities of the blow cavity mold, but also the stretching rod, the blow core mold, and the mechanism for supporting or driving the same, increase the size and cost of the apparatus. Was.

As another problem, conventionally, the preform cannot be taken out without completely pulling out the injection core mold from the preform, and the rotary injection molding apparatus cannot transport the preform from the injection molding section to the next process. Disappears. When the injection core mold is completely pulled out from the preform in this way, there is a problem that the drawing stroke becomes longer and the overall height of the device becomes higher.

[0015] Still another problem is that when a hot parison type blow molding is performed by a rotary transfer type blow molding machine,
The injection molded preform is rotated and conveyed to the blow molding section without fail. Here, for example, when an abnormality occurs in the blow molding portion, the injection molding of the preform has to be stopped. However, once the injection molding section is powered down, a long start-up time is required when restarting. This is because an injection device, a hot runner type, and the like require many resin heating mechanisms.

Therefore, as described above, the throughput of the entire apparatus does not increase, and in addition, once an abnormality occurs, much time is required to start up the apparatus, and the production efficiency is further reduced.

Accordingly, an object of the present invention is to provide an injection stretch blow molding apparatus and method capable of shortening the injection molding cycle time and shortening the cycle time of the entire apparatus while sufficiently securing the cooling time of the preform. Is to provide.

Another object of the present invention is to provide a high-efficiency injection stretch blow molding apparatus and method capable of increasing the operation rate of the blow mold while reducing the number of cavities of the blow mold and reducing the cost. It is in.

Another object of the present invention is to provide an injection-stretch blow-molding apparatus and method which utilizes the thermal energy efficiency of the hot parison method and has the stability of the temperature distribution of the preform by the cold parison method. .

Another object of the present invention is to prevent uneven temperature or deformation even if the release temperature of the preform released from the injection cavity mold is increased, and to release the preform from the injection core mold. An object of the present invention is to provide an injection stretch blow molding apparatus and method capable of sufficiently cooling before, and stably blow molding at an appropriate temperature for blow molding thereafter.

Still another object of the present invention is to provide an injection stretch blow molding apparatus and method capable of performing blow molding in a state where the temperature difference between the inner and outer walls of a preform by an injection core mold and an injection cavity mold is reduced. It is in.

Still another object of the present invention is that the capacity is 1 to 3
An object of the present invention is to provide an injection stretch blow molding apparatus capable of performing blow molding of a general-purpose medium-sized container of about 1 liter with high efficiency.

Still another object of the present invention is to provide a blow molding apparatus which can efficiently heat a lower region of a neck of a preform to set an appropriate temperature for blow molding.

Still another object of the present invention is to reduce the temperature difference between the inner and outer walls of the preform, adjust the temperature to a suitable temperature for the blow using a time for the temperature reduction, and then perform blow molding. It is to provide a blow molding apparatus which can be used.

Still another object of the present invention is to provide an injection-stretch blow-molding apparatus and method which does not require useless blow molding at the time of startup of the apparatus, or which does not require stopping the operation of the entire apparatus when a blow molding section is abnormal. Is to provide.

[0026]

According to one aspect of the present invention, there is provided an injection stretch blow molding apparatus comprising: a preform molding station for injection molding a preform; a blow molding station for stretching blow molding a container from the preform;
A transfer station for transferring the preform from the preform molding station to the blow molding station, wherein the preform molding station intermittently interposes at least a plurality of injection core molds that are separately arranged along a transport path. Molding, which has a circulating transport section for circulating and transporting, and an injection cavity mold that is driven to clamp relative to the injection core mold stopped in the middle of the transport path, and injection-molds the preform. And a take-out unit that relatively releases the injection core mold and the preform stopped in the middle of the transport path and takes out the preform from the injection core mold. And

The method according to one aspect of the present invention is directed to an injection stretching blow molding method for blow molding a container from a preform holding heat during injection molding, wherein the container is molded using at least an injection core mold and an injection cavity mold. Preform, the step of releasing from the injection cavity mold, while holding the preform in the injection core mold, while cooling the preform by the injection core mold,
Conveying the injection core mold to a take-out section along a conveyance path, and, at the take-out section, releasing the injection core mold from the preform, and taking out the preform,
And thereafter, blow molding the container from the preform that retains heat during injection molding.

According to each of the above aspects, after the preform injection-molded in the injection molding section is cooled by the injection cavity mold and the injection core mold, only the injection cavity mold is released from the preform. Thereafter, the preform is transported to the preform take-out section by the injection core type. During the transportation and at the preform take-out section, the preform is cooled by the injection core mold, and then the preform is taken out. Accordingly, even after the injection cavity mold is released from the injection molding section, the cooling time of the preform is sufficiently ensured by cooling with the injection core mold. For this reason, the release temperature of the preform at the time of releasing the injection cavity mold in the injection molding section can be increased, the injection molding cycle time is shortened, and the cycle time of the entire apparatus is also shortened. Further, even if the injection cavity mold is released at a high temperature, the deformation of the preform can be prevented by the injection core mold. In addition, the preform shrinks when it cools and adheres tightly to the injection core mold, increasing the cooling efficiency and preventing the crystallization and opacity of the body due to insufficient cooling, as well as stabilizing the cooling process. Accordingly, the heat quantity of the preform can be stabilized, and the thickness distribution of each container that is continuously blow-molded can be stabilized. Further, since the preform is transported by the injection core type, a stroke for extracting the preform is not required, and the overall height of the apparatus can be reduced.

An injection stretch blow molding apparatus according to another aspect of the present invention comprises a preform molding station for injection molding a preform, a blow molding station for stretch blow molding a container from the preform, and a preform molding station. A transfer station for transferring the preform to the blow molding station;
Wherein the preform molding station comprises: a first circulating transport unit that intermittently circulates and transports at least a plurality of injection core molds that are separately arranged along a first transport path;
An injection cavity mold that is driven to clamp relative to the injection core mold that is stopped in the middle of the conveyance path;
2) The injection molding section for simultaneously injection molding the preforms, and the injection core mold and the preform stopped in the middle of the first conveyance path are relatively released from the injection molding section, and the injection core is driven. A take-out unit for taking out the preform from a mold, wherein the blow molding station intermittently circulates the preform transferred from the preform molding station via the transfer station along a second transport path. A second circulating transport unit for transporting, and a blow mold that is clamped to the preform stopped in the middle of the second transport path, and includes n (1 ≦ n <N) preforms; and a blow molding unit for simultaneously blow molding the n number of containers.

A method according to another aspect of the present invention is directed to an injection stretch blow molding method for blow molding a container from a preform holding heat during injection molding, wherein at least an injection core mold and an injection cavity mold are used. N (N ≧
2) releasing the preforms from the injection cavity mold, and cooling the preforms with the injection core mold while holding the preforms in the injection core mold; Conveying the mold to a take-out section along a first circulation conveyance path, releasing the injection core mold from the preform at the take-out section, and taking out the preform; Transferring the preform to a transport member transported along a second circulation transport path; and transporting the transport member supporting the preform to a blow molding unit along the second transport path. In the blow molding section, n (1 ≦ n <N)
The method is characterized in that n containers are blow-molded simultaneously from n preforms in a blow mold that is clamped to the preforms.

According to the other aspect described above, since the number of simultaneous blow moldings is set to be smaller than the number N of simultaneous injection moldings, the number of cavities of the blow mold is reduced, and the cost of the consumable mold is greatly reduced. Can be reduced to Furthermore, since the number of blow core type and extension rods and the mechanism for supporting or driving the same are also reduced, the size and cost of the apparatus can be reduced. In addition, in the shortened molding cycle, the N preforms simultaneously molded are blow-molded separately by n (n <N) a plurality of times, so that the n cavities of the blow cavity mold are blown. The operating rate increases.

An apparatus according to still another aspect of the present invention includes a preform molding station for injection molding a preform, a blow molding station for stretch blow molding a container from the preform, and a blow molding station for the blow molding from the preform molding station. And a transfer station for transferring the preform, wherein the preform molding station intermittently circulates and conveys at least a plurality of injection core molds spaced apart along a first conveyance path. A circulating transport section, an injection cavity mold that is driven to be clamped relatively to the injection core mold stopped in the middle of the transport path, and the preform in an upright state with an opening neck portion facing upward; An injection molding section for injection molding the injection core mold and the pre-press stopped in the middle of the first transport path. And relatively release drive and over arm includes a take-out unit for taking out the preform of the erecting state from the injection core mold, the blow molding station,
A second circulating transport unit that intermittently circulates and transports along the second transport path in an inverted state with the neck opening the preform transferred from the preform molding station via the transfer station downward; A blow mold for clamping the preform stopped in the middle of the second transport path, and a blow molding unit for blow molding the container, A receiving mechanism for receiving the reform in an upright state,
And a reversing mechanism for reversing the received preform to an inverted state.

A method according to yet another aspect of the present invention is a method for transferring an injection-molded preform from a preform molding station to a blow molding station via a transfer station, and the container from the preform at the blow molding station. In the injection stretch blow molding method of blow molding, in the preform molding station, the preform is injection molded in an upright state with the opening neck part upward, and the transfer station is
The preform in an upright state is turned upside down and transferred to the blow molding station in an inverted state, and the blow molding station blow-molds a container from the preform in an inverted state.

In still another embodiment described above, the preform is formed in an upright state with the neck portion facing upward.
For this reason, the injection mold clamping is vertical, and space is saved.
In addition, since the resin is usually filled from the bottom side of the preform, a stable arrangement in which the injection device and the injection cavity mold are arranged below and the injection core mold is arranged above can be adopted. Also,
When the preform is transported to the blow molding station, the preform is in an inverted state, so that the preform can be easily self-standing by utilizing the opening of the neck portion. further,
Since the stretch rod and the blow core mold are located below the preform, they can be arranged using the space in the machine base, and the overall height of the blow molding section can be reduced.

Further, by using a different mechanism for receiving and inverting, receiving can be performed during inversion, so that a device with a fast cycle can be easily handled.

Here, it is preferable that a heating section for heating the preform conveyed to the blow molding section is provided in the middle of the second conveyance path.

In this way, the preform can be set at a suitable temperature for blow molding by cooling by the injection mold and reheating of the cooled preform, and the temperature stability in each cycle is improved. Also, the preform has a retained caloric value,
By applying a certain temperature, in many cases, a suitable temperature for blow molding is obtained, so that a relatively short heating time is sufficient, and a container having a desired thickness can be obtained by further providing an axial temperature distribution of the preform during the heating. . Further, even if the N injection-molded N preforms are blow-molded separately into n pieces (N / n) times, it is possible to easily perform the control for reducing the variation in temperature for each blow-molding. .

Further, it is preferable that the heating section is provided with a rotation mechanism for rotating the preform to be heated around the center of the vertical axis.

In this way, uneven heating can be reduced, and uneven temperature in the circumferential direction of the preform can be reduced.

Further, the second circulating transport section includes the second circulating transport section.
It is preferable that a plurality of conveying members are conveyed at equal intervals on the conveying path, and each of the conveying members has a supporting portion for supporting the preform in an inverted or upright state.

The blow mold provided in the blow molding section has a plurality of blow cavities arranged at a blow molding pitch P, and the arrangement pitch of the plurality of carrying members on the second carrying path is It is preferable to set the pitch P equal to the pitch P.

The arrangement pitch of the preforms arranged in the heating section of the present invention is larger than in the case of the narrow pitch arrangement arranged in the heating section in the conventional two-stage system.
However, in the present invention, since it is sufficient to apply a small amount of heat energy in addition to the retained heat after the injection molding, the heating time can be reduced, and it is not necessary to lengthen the entire length of the heating portion unlike a cold parison.

The blow molding pitch of the blow molding station is larger than the preform molding pitch of the preform molding station, and the receiving mechanism converts the preform from the preform molding pitch to the blow molding pitch. Preferably, a conversion mechanism is included.

Preferably, the transfer station converts the pitch of the preform from the preform molding pitch to the blow molding pitch after receiving the preform from the preform molding station, and then inverts the preform.

With the above arrangement, even when the preform molding pitch and the blow molding pitch are different and the blow molding pitch is large, the preform can be converted to the blow molding pitch immediately after receiving the preform by the receiving mechanism. In addition, the present invention can easily cope with a molding device that requires pitch conversion.

Further, since the diameter of the preform is smaller than that of the product, the number of preforms can be increased, and the pitch can be optimized in blow molding.

The blow molding pitch of the blow molding station is larger than the preform molding pitch of the preform molding station, and the reversing mechanism is configured to convert the preform from the preform molding pitch to the blow molding pitch. Preferably, a conversion mechanism is included.

Thus, the preform can be converted from the preform molding pitch to the blow molding pitch together with the reversing operation by the reversing mechanism, and the pitch conversion can be performed immediately after the receiving operation by the receiving mechanism. Can easily be adapted to the molding apparatus.

[0049] The preform has an outer diameter portion larger than the body portion at the neck portion, and the receiving mechanism has a holding member for holding the preform by contacting the lower surface of the outer diameter portion larger than the body portion. Is preferred.

Thus, when the neck portion has an outer diameter portion larger than the body portion, for example, a support ring,
The preform can be securely held by using the large outer diameter portion by the receiving mechanism, and since the preform is hardly contacted with the body portion, the preform is not damaged.

The holding member has an opening / closing mechanism for holding and releasing the preform, and the opening / closing mechanism has a larger outer diameter portion than the body portion of the preform in a closed state and a larger opening diameter than a portion adjacent to the body portion. It is preferable to have a slightly larger preform insertion portion.

In this way, the preform insertion portion of the opening / closing mechanism provided on the holding member can reliably hold the preform without rattling, and can easily and reliably open the opening / closing mechanism when removing the preform. The preform can be released.

Preferably, the receiving mechanism has a holding member, and the holding member has a holding portion for holding the preform by contacting at least a part of the bottom and the body of the preform.

In this way, the bottom and the trunk of the preform can be securely held by the holding portion, and the preform can be held without being affected by the shape of the molded product.

It is preferable that the holding member has cooling means for cooling the outer wall of the preform.

In this way, the preform can be cooled while the preform is being held by the cooling means provided on the holding member. In particular, the outer wall of the preform is not in contact with the core pins and the like, and the outer wall of the preform is higher than the inner wall. The temperature of the inner and outer walls can be reduced in a short time by cooling the outer wall because the temperature is high.

The reversing mechanism has a holding mechanism capable of simultaneously holding a preformed number of preforms simultaneously, and the holding mechanism is configured to simultaneously hold the preforms at the same time as the preforms stopped at the receiving position. It is preferable to simultaneously reverse the delivery.

In this case, the number of preforms differs from the number of blow moldings, and even if the number of preforms is larger than the number of blow moldings, the number of preforms is not transferred for each number of blow moldings. The delivery operation can be performed once by transferring the image data to the transport member at a time, so that the delivery operation can be simplified and the configuration can be simplified accordingly.

It is preferable that the receiving mechanism has a horizontal moving mechanism for horizontally moving from immediately below the take-out portion of the injection molding station to the preform holding position of the reversing mechanism.

In this case, the delivery to the reversing mechanism after receiving the preform is performed by a simple movement only by horizontally moving the preform holding position of the reversing mechanism from immediately below the take-out portion of the injection molding station. The horizontal movement mechanism can also have a simple configuration.

The reversing mechanism preferably has a horizontal drive for horizontally moving between the receiving mechanism and the preform receiving position of the conveying member in the blow molding station.

In this case, the reversing mechanism is moved between the receiving mechanism and the conveying member by horizontally moving the receiving mechanism and the preform receiving position of the conveying member in the blow molding station by the horizontal driving device. Can,
The movement can be simplified and the structure can be simplified.

It is preferable that the reversing mechanism has a standby position in which the preform has a neck portion facing downward and waits until the same number of conveying members as the preform are aligned with the preform receiving position.

In this case, it is necessary to invert the preform from the established state to the inverted state when the conveying member is aligned with the preform receiving position by making the reversing mechanism stand by at the standby position while the preform is in the inverted state. Therefore, the preform can be delivered to the transport member with a small number of operations immediately after the transport member is aligned with the receiving position, and the delivery time of the preform can be reduced.

The preform is allowed to cool for a time sufficient to alleviate the temperature difference between the inner and outer walls of the preform between the release of the injection core mold and the start of the blow molding step. It is preferable to have a step.

In this way, the cooling time of the injection core mold closely contacting the inner wall of the preform can be secured longer than before, so that a relatively steep temperature gradient occurs in the cross section of the preform wall, and the temperature near the outer wall is lower than that near the inner wall. Will be higher. By providing the cooling step, the temperature gradient can be moderated, and the inner and outer walls of the preform can be set to the appropriate blow temperature.

The step of removing the preform is performed after the preform is cooled by the injection core mold until the temperature of the preform becomes lower than the appropriate temperature for blow molding. It is preferable that a step of heating the preform be further provided in the middle of the second conveying path for conveying.

After the preform is cooled to a temperature lower than the appropriate temperature for blow molding, the preform is heated in the middle of the second conveyance path, so that even if the temperature irregularity of the preform during injection molding matches, the preform is removed. Insufficient molding during blow molding can be prevented.

In the step of heating the preform, it is preferable to rotate the preform around the longitudinal axis.

By rotating the preform around the vertical axis in the preform heating step, the preform can be uniformly heated in the circumferential direction.

In the blow molding step, n (n ≧ 2) blow cavities arranged at a blow molding pitch P are used to blow mold the n containers from the n preforms at the same time. In the step of transporting the preform on the second transport path, the preform is transported while maintaining the arrangement pitch of the transport members equal to the pitch P. In the step of transporting the preform, the n preforms are transported. It is preferable that the step of simultaneously transferring the reforms to the n transport members is repeatedly performed a plurality of times.

Further, in a method according to still another aspect of the present invention, in the blow molding step, n (n ≧ 2) blow cavities arranged at a blow molding pitch P are used at the same time for the n preforms. In the step of transporting the preform on the second transport path, the preform is transported while maintaining the arrangement pitch of the transport members equal to the pitch P, and the preform is transported. In the step, it is preferable that the step of simultaneously transferring the n preforms to the n transport members is repeated a plurality of times.

In this case, the transfer pitch conversion on the second transfer path is not required. In addition, even if the number N of simultaneous injection moldings increases, the number n of transfer is smaller than that in the case of transferring N simultaneously. Therefore, it is easy to position accurately on the conveying member, and therefore, a complicated mechanism is not adopted.

A method according to yet another aspect of the present invention includes a step of simultaneously injection-molding N polyethylene terephthalate preforms using at least an injection core mold and an injection cavity mold; Releasing the mold, and transporting the preform to the take-out unit while cooling the preform in the injection core mold,
In the removal section, after the preform is cooled to a required cooling temperature, a step of releasing the preform from the injection core mold and removing the same, and a step of heating the extracted preform to a required temperature. And thereafter, blow molding n containers simultaneously from the n preforms, wherein each of the simultaneously molded numbers N, n is N: n =
The ratio is set to 3: 1.

According to the experiments conducted by the present inventors, in the case of a general-purpose medium-sized container having a relatively narrow mouth of about 1 to 3 liters (the opening diameter of the neck portion 2 is about 28 to 38 mm) required in the market, the simultaneous It has been found that it is optimal to set the ratio of the molding numbers N, n to N: n = 3: 1. In other words, in the case of the present invention in which the preform is continuously cooled by the injection core mold after the mold is released from the injection cavity mold and then blow-molded, the time required for the preform molding for the general-purpose medium-sized container is the same as the conventional one. And the injection molding cycle time is reduced to about 3/4,
I found that about 5 seconds was enough. On the other hand, a blow molding cycle time of about 3/6 to 4.0 seconds is sufficient. Therefore, when this injection molding cycle time is T1 and the blow molding cycle time is T2, almost T1: T2 =
In the case of efficiently molding a general-purpose medium-sized container, it is optimal to set the simultaneous molding numbers N and n according to the above-mentioned ratio.

In the injection molding step of the preform, it is preferable to injection-mold the preform in which the maximum thickness of the body is 3.0 to 4.0 mm.

If the thickness is more than this, the temperature difference between the inner wall and the outer wall of the preform becomes too large, and a time for relaxing the temperature difference and a special apparatus for heating the inner wall are required.

A method according to still another aspect of the present invention comprises a step of simultaneously injection-molding N (N ≧ 2) preforms, and a step of holding n (1 ≦ n <N) preserving heat during the injection molding. And the step of simultaneously blow molding n containers from the preform described above, respectively.
It is characterized in that each of the simultaneous molding numbers N and n where n is an integer is set.

If N / n is an integer, for example, the N preforms simultaneously injection-molded in the first cycle are all used for the blow molding of n (N / n) integer times. In the second cycle, it will not be mixed with any of the N preforms formed at the same time and blow molded at the same time. If the blow molding is performed by mixing preforms having different injection molding cycles, the transport sequence is different from the case where the preforms molded in the same injection molding cycle are simultaneously blow molded, but the control and structure are complicated. The present invention can solve the problem.

A blow molding apparatus according to still another aspect of the present invention is provided with a circulating transport section for forming a substantially rectangular transport path, circulating and transporting a molded product, and disposed on one side of the circulating transport section.
A receiving section that receives an injection-molded preform and transfers it to the circulating transport section, and is disposed on one side of the circulating transport section adjacent to the one side provided with the receiving section in the transport direction,
A heating unit for heating the preform received by the receiving unit, a preform disposed on one side of the circulating conveyance unit adjacent to one side provided with the heating unit in the conveyance direction and heated by the heating unit A blow molding unit for forming a container by blow molding, and a container formed on the one side of the circulating transport unit adjacent to the one side provided with the blow molding unit in the transport direction and molded by the blow molding unit And a discharge unit that discharges to the outside.

By arranging a receiving section, a heating section, a blow molding section, and a discharge section along each side of the circulating conveying section forming a substantially rectangular conveying path along the conveying direction, each side of the conveying path can be formed. It can be used effectively to perform one cycle of molding, and the inside of the circulating transport unit can be used as a mold clamping movement stroke of the mold clamping mechanism of the blow molding device in the blow molding unit, reducing space. It is possible to realize a compact device.

A method according to a still further aspect of the present invention is a method wherein a preform conveyed in an inverted state in which a neck portion faces downward or in an upright state in which the neck portion faces upward is loaded into a blow molding section before being carried into the blow molding section. In a blow molding apparatus that heats at a heating unit, a plurality of the heating units are arranged at intervals in a vertical direction on a side of a transport path of the preform, and each extends along a transport direction of the preform. A plurality of first heaters, a reflector disposed opposite to the first heater with a preform conveyance path as a boundary,
A plurality of second heaters extending along the transport direction of the preform on both sides of the transport path of the preform;
Wherein the height of the second heater in the vertical direction is set at a position facing a blow molding target area near the neck portion of the preform.

The region below the neck portion when the preform is erected is a region to be stretched and oriented even though it is arranged closest to the cavity surface of the blow cavity mold. By heating this region by the second heaters on both sides of the preform, the region can be heated to a higher temperature than the body region heated by the first heater arranged on one side, and a high degree of stretching orientation can be secured. Further, since the first heater is disposed only on one side, energy can be saved. In addition, since the heating efficiency in the lower region of the neck is increased, the heating time can be reduced, and the total length of the heating section can be shortened.

An apparatus according to still another aspect of the present invention is a blow molding apparatus for intermittently transporting a preform to a blow molding section via a heating section, wherein the heating section is configured to transport the preform. On the side of the path, has a heater extending along the transport direction of the preform, in the transport path between the heating unit and the blow molding unit, at least one preform is stopped, It is characterized in that a standby unit is provided for waiting the carry-in to the blow molding unit.

The provision of the standby section at the front of the blow molding section in the transport direction can alleviate the temperature distribution of the synthetic resin preform having poor thermal conductivity. Usually, the heating in the heating section is performed from around the preform, so that the inner wall temperature of the preform is lower than that of the outer wall. In order to ease the process of the temperature distribution, the blow molding characteristics are stabilized by waiting at least the preforms for the number of simultaneous blow moldings after heating.

It is preferable that the standby section has a temperature control member for controlling the temperature of the preform to give a temperature distribution.

By positively adjusting the temperature of the preform during the temperature relaxation time in the standby section, a temperature distribution for a proper blow temperature or a more reliable temperature distribution which cannot be obtained by simply rotating and heating the preform. Can be provided.

This temperature control member can be inserted into the preform and can be controlled by a temperature control core for controlling the temperature of the inner wall surface of the preform.

The temperature control member is a temperature control pot having a cylindrical portion disposed around the preform. The temperature control pot divides the zone in the axial direction of the preform, and And by independently controlling the temperature.

Further, at one or a plurality of locations in the circumferential direction of the preform, different temperature distributions are provided in the circumferential direction of the preform by using a temperature control member extending along the axial direction of the preform. You can also.

[0091] An apparatus according to still another aspect of the present invention is directed to an injection stretching apparatus having a preform molding section for molding a preform, and a blow molding section for blow molding a container from the preform holding heat during molding. In the blow molding apparatus, a discharge guide section is provided at a position on the way of transporting the preform from the preform molding section to the blow molding section, for discharging and guiding the preform not transported to the blow molding section to the outside of a transport path. It is a feature.

[0092] The machine has a machine base on which the preform molding section and the blow molding section are mounted, and the discharge guide section includes a preform drop opening formed in the upper surface of the machine base, And a shooter for guiding the preform to the side of the platform.

[0093] A method according to still another aspect of the present invention is that a preform is injection-molded in a preform molding section, and the preform is conveyed to a blow molding section, and the preform having heat during molding is removed from the preform. In an injection stretch blow molding method for blow molding a container, a container molding operation mode,
A step of switching to any one of a preform molding operation mode and, when switched to the preform molding operation mode, the preform repeatedly molded by the preform molding section, The preform is discharged to the outside of the transport path on the way of the preform transport path.

According to each of the above-described embodiments, a defective preform at the start of molding can be discharged without being transported to the blow molding section, so that unnecessary blow molding is not required. In addition, when the blow molding section is abnormal or adjusted, the blow molding section can be repaired and adjusted without stopping the operation of the preform molding section. Once the preform molding unit is powered down, it takes a lot of startup time to return the various heating mechanisms to a moldable state, but according to the present invention, such unnecessary startup time is not required. .

[0095]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments to which the method and apparatus of the present invention are applied will be specifically described below with reference to the drawings.

One embodiment of the present invention is shown in FIGS.

FIGS. 1 to 26 show an injection stretch blow molding apparatus according to one embodiment.

(Overall Configuration of Apparatus) FIGS. 1 to 3 are a plan view, a front view, and a left side view of the apparatus of this embodiment, respectively.
FIG. 4 is an enlarged view showing a main part of the apparatus of this embodiment. As shown in each figure, the preform molding station 10, the transfer station 200, and the blow molding station 300 are roughly arranged on the machine base 8.

As shown in FIG. 2, the preform molding station 10 has injection core molds 50 at two positions separated by a rotation angle of 180 °, and intermittently interposes the injection core molds 50 along the rotary conveyance path. It has a turntable 30 as a first circulating transport unit for circulating and transporting. At each stop position of the injection core mold 50, an injection molding portion 14 is provided at a position facing the injection device 12, and an ejection portion 16 is provided facing the injection molding portion 14. The injection molding unit 14 has an injection cavity mold 42 that is driven to clamp relative to the injection core mold 50, and simultaneously performs N (N ≧ 2), for example, N = 4 preforms 1 by injection molding. . On the other hand, take-out unit 1
In 6, the injection core mold 50 is driven to be released relatively to the preform 1 so that the injection core mold 50 is
Can be removed. In this embodiment, the neck portion of the preform 1 is formed by a neck cavity mold 60 described later, and the preform 1 is held by the neck cavity mold 60 and the injection core mold 50 and taken out by the turntable 30. It is transported to the unit 16. And take-out part 1
In No. 6, the preform 1 is released from the neck cavity die 60 after the injection core die 50 is partially released, so that the preform 1 is taken out.

As shown in FIG. 1, the blow molding station 300 includes four sprockets 320a to 320d.
And a second circulating transport section 302 composed of a transport chain 322 and the like spanned over them. The chain 322 has a plurality of, for example, 1
The zero transport member 330 is fixed, and the preform 1 or the bottle 6 is supported by each transport member 330. A receiving section 3 that receives the preform 1 from the transfer station 200 is provided on the transfer path of the transfer member 330.
04, a heating unit 306 for heating the preform 1, and a standby unit 3 for temporarily waiting the heated preform 1
08, a blow molding unit 310 that stretch-blow-molds the bottle 6 from the preform 1, and a bottle removal unit 312 that takes the bottle 6 out of the apparatus.

The blow molding section 310 has a blow mold 378 which is clamped to the preform 1 and has n (1 ≦ n).
<N) For example, one bottle 6 is blow-molded from n = 1 preform 1.

The transfer station 200 transfers the preform 1 taken out from the take-out section 16 of the preform molding station 10 to the receiving section 304 of the blow molding station 300. At an unloading section 16 of the preform molding station 10, N preforms 1 at the same time as the injection molding section 14 are taken out.
In the transfer station 200, the preform 1 is transferred a plurality of times by the simultaneous molding number n in the blow molding section 310 of the blow molding station 300 in a plurality of times. In the case of the present embodiment, four preforms 1 simultaneously taken out by the take-out section 16 are transferred to the receiving section 304 one by one. In the preform molding station 10, the preform 1 is injection-molded in an upright state. On the other hand, the preform 1 is turned upside down in the transfer station 200, and the preform 1 is inverted in the blow molding station 300. It is transported in a state.

(Preform molding station 10) First, the preform molding station 10 will be described with reference to FIG.
This will be described with reference to FIGS.

(Injection molding section 14 and first circulating transport section 3)
0) Injection molding section 1 of preform molding station 10
4, a lower mold clamping plate 20 fixed on the machine base 8 is provided as shown in FIGS. This lower mold clamping plate 2
The upper mold clamping plate 22 having a circular shape, for example, is disposed over the installation area of the injection molding section 14 and the preform take-out section 16 above 0. The upper mold clamping plate 22 is provided with four tie bars 2 provided at four locations around the injection molding portion 14.
4 can be moved up and down. As shown in FIGS. 1, 2 and 4, a fixing plate 26 is provided at the upper end of the tie bar 24, and a mold clamping cylinder 28 is fixed to the fixing plate 26. The mold clamping cylinder 28 drives a mold clamping rod 28a (see FIG. 4), and the upper mold clamping plate 22 is driven up and down by the mold clamping rod 28a.

As shown in FIGS. 2 to 4, the upper mold clamping plate 22
A rotatable disk 30 as a first circulating transport unit is rotatably supported on the lower surface of. As shown in FIG. 7, the rotary disk 30 is fixed to a rotary shaft 34 that is driven to rotate by a rotary actuator 32 fixed to the upper mold clamping plate 22. As shown in FIG. 5, which is a bottom view of the turntable 30,
Two rows of injection core dies 50 and neck cavity dies 60 are supported on the turntable 30 at positions corresponding to the respective parts 14 and 16. The details of the injection core mold 50 and the neck cavity mold 60 will be described later.

As shown in FIG. 2 and FIG.
Is provided with a hot runner mold 40 for nozzle-touching the injection device 12, and an injection cavity mold 42 is fixed on the hot runner mold 40. The injection cavity mold 42 has the number N of simultaneous moldings in the injection molding section 14, for example, four cavities. The injection cavity mold 42 is capable of cooling an injection-molded preform, and circulates a coolant, for example, normal-temperature water in the cavity mold.

As shown in FIGS. 4 to 8, the two rows of injection core dies 50 supported by the rotating disk 30 have the number N of simultaneously molded core pins 52 in each row. As shown in FIG. 7, the base end 52a of the core pin 52 is
And a core fixing plate 56 fixed to the lower surface of the core pressing plate 54. The mold clamping cylinder 28 is driven and the mold clamping rod 2
8a drives the upper mold clamping plate 22 downward, and the upper mold clamping plate 2
Each of the core pins 52 of the injection core mold 50 is integrally formed with the turntable 30, the core pressing plate 54, and the core fixing plate 56 supported by the core 2.
Is driven downward to be driven to clamp the injection cavity mold 42.

As shown in FIGS. 7 and 11, the two rows of neck cavity dies 60 supported by the rotary disk 34 are composed of a pair of split dies 62a and 62b. , 62b are provided at the same time. Dividing plates 64a and 64b for fixing a pair of split dies 62a and 62b are provided in each row, and the dividing plates 64a and 64b constitute a neck fixing plate 64.
Also, as shown in FIGS.
A neck pressing plate 65 for pressing and driving the neck fixing plate 64 downward is disposed on the upper surface side of b. Further, guide plates 66 are provided to support the lower surfaces of both ends in the longitudinal direction of the neck fixing plate 64. Dividing plates 64a, 64
b is set to a normally closed state by a spring 64c shown in FIG. Also, as shown in FIG. 5, wedge holes 64d are provided in each of the divided plates 64a and 64b at both ends in the longitudinal direction. After the neck fixing plate 64 is carried into the preform take-out part 16, the wedge holes 64d are formed.
The split plates 64a and 64b are driven to open along the guide plate 66 by a split-type opening cam 108, which will be described later, which is driven toward.

FIGS. 9 and 6 are enlarged sectional views of a portion A in FIG.
As shown in FIG. 5, an elevating pin 70 whose lower end is fixed to the guide plate 66 extends upward, and a flange 70a is formed at the upper end of the elevating pin 70. On the other hand, the guide cylinder 72 extending downward from the lower surface of the turntable 30
Is fixed, and the elevating pin 70 is disposed in the guide cylinder 72. A return spring 74 is disposed between the bottom inner wall of the guide cylinder 72 and the flange 70 a of the elevating pin 70. Due to the upward biasing force of the return spring 74, the guide plate 66 is constantly urged to move upward, and as a result, the neck pressing plate 65 is always in close contact with the lower surface of the core fixing plate 56.

By maintaining the close contact state between the core fixing plate 56 and the neck pressing plate 65, the mold clamping state between the injection core mold 50 and the neck cavity mold 60 is set. Also, the external force (described later) applied by the preform take-out section 16 lowers the elevating pin 70 against the urging force of the return spring 74, and moves the neck pressing plate 65 away from the lower surface of the core fixing plate 56. , And presses the neck fixing plate 64 downward. As a result, the core pin 52 of the injection core mold 50 is driven to be released from the preform 1 in which the neck portion 2 is held by the neck cavity mold 60.

(Preform Take-Out Unit 16) Next, the configuration of the preform take-out unit 16, particularly the preform take-out drive mechanism, will be described. In this embodiment, the preform take-out drive mechanism is constituted by the neck release drive section 80 and the split mold release drive section 100. The neck release drive unit 80
As shown in FIG. 8, a first cylinder 82 is provided.
The cylinder 82 is fixed to a first cylinder fixing plate 84b supported by the upper mold clamping plate 22 via a first column 84a. The first cylinder 82 drives the first lifting plate 86 up and down via the first piston rod 82a. Press drive rods 88 are provided at both ends in the longitudinal direction of the first elevating plate 86, respectively. On the other hand, the upper mold clamping plate 22 is provided with a hole 22a penetrating from the upper surface to the lower surface.
a. The initial position of the first elevating plate 86 is set to a position where the tip of the pressing drive rod 88 does not protrude from the lower surface of the upper mold clamping plate 22 so as not to hinder the rotational driving of the turntable 30.

As shown in FIG. 8, the rotary plate 30, the core pressing plate 54 and the core fixing plate 56 have holes 2 in the upper mold clamping plate 22.
The holes 30a, 54a, 5
6a. Then, on the upper surface of the neck pressing plate 65,
A driven rod 68 disposed in each of the holes 30a, 54a, 56a is fixed.

Therefore, when the first cylinder 82 is driven, the first piston rod 82a, the pressing drive rod 8
The neck pressing plate 65 and the neck fixing plate 64 are driven downward against the urging force of the return spring 74 via the driven rod 8 and the driven rod 68. As a result, FIG.
As shown in FIG. 0, the preform 1 in which the neck portion 2 is held by the neck cavity mold 60 is
Of the core pins 52 are driven to release. In the present embodiment, the core pin 52 of the injection core mold 50 does not need to be completely released from the open end of the preform 1, and at least air flows between the core pin 52 and the inner wall of the preform 1. It suffices if there is a gap to enter. In the present embodiment, the descending stroke of the neck fixing plate 64, that is, the release stroke of the core pin 52 (the length L shown in FIG. 10) is, for example, 50 m.
m.

Next, the split mold opening drive unit 100 will be described. The split mold opening drive unit 100 has, for example, two second cylinders 102 as shown in FIGS.
As shown in FIG. 11, the second cylinder 102 is fixed to a second cylinder fixing plate 104b supported by a first elevating plate 86 via a second support 104a. Therefore, the first lifting plate 86 is moved by the first cylinder 82.
Is driven up and down, the second cylinder 10
2 is also driven up and down. This second cylinder 1
Numeral 02 drives the second lifting plate 106 up and down via the second piston rod 102a. Split-type opening cams 108 are fixed to the second lifting plate 106 at both ends in the longitudinal direction. This split-type opening cam 10
The lower end of 8 is a split plate 64 that constitutes a neck fixing plate 64.
It has a wedge shape corresponding to the wedge hole 64d provided in each of the holes 64a and 64b. Therefore, the second cylinder 10
2, the split mold opening cam 108 is driven downward to insert the wedge portion at the tip thereof into each of the wedge holes 64d of the neck fixing plate 64, thereby opening the pair of split plates 64a and 64b. Driven. Then, the pair of split dies 62a and 62b fixed to the pair of split plates 64a and 64b, respectively, are opened and the preform 1 is taken out from the neck cavity die 60. In the present embodiment, the drive timing of the second cylinder 102 is set after the drive of the first cylinder 82.

Next, the operation of the preform molding station 10 in the above embodiment will be described.

(Injection molding process in injection molding section 14)
By driving the mold clamping cylinder 28 to lower the upper mold clamping plate 22, the injection core mold 50 and the neck cavity mold 60 are driven to clamp the injection cavity mold 42. After setting the mold clamping state shown in FIG. 4, the injection molding material of the preform 1, for example, polyethylene terephthalate (PET) is moved through the hot runner mold 40 by advancing and rotating the screw in the injection device 12. The cavities defined by the molds 42, 50, and 60 are filled and injection molding of the preform 1 is performed.

(Cooling Step in Injection Molding Section 14) In the injection cavity mold 42, the injection core mold 50, and the neck cavity mold 60, a coolant, for example, normal-temperature water is circulated. It can be cooled immediately.

(Release Step of Injection Cavity Mold 42 in Injection Molding Section 14) By driving the mold clamping cylinder 28 to drive the upper mold clamping plate 22 upward, the injection cavity mold 42 is opened as shown in FIG. The injection core mold 50 and the neck cavity mold 60 can be driven upward with respect to 42. At this time, since the neck portion 2 of the preform 1 forms an undercut in the mold release direction, the injection-molded preform 1 is held by the injection core mold 50 and the neck cavity mold 60, and the injection core The mold 42 is released from the mold 42.

The mold release start timing in the injection molding section 14 can be sufficiently earlier than the conventional mold release start timing. In other words, the cooling time of the preform 1 in the injection molding section 14 can be reduced. This is preform 1
This is because even after the injection cavity mold 42 is released from the mold, the state in which the core pin 52 of the injection core mold 50 is inserted into the preform 1 can be maintained, and deformation of the preform 1 due to heat shrinkage can be prevented. . Therefore, the release temperature of the preform 1 in the injection molding section 14 may be a temperature at which a skin layer that can maintain the shape even after the injection cavity mold 42 is released is formed on the surface of the preform 1. May be higher than the mold release temperature. Even at such a high mold release temperature, the preform 1 shrinks to the side of the injection core mold 50 in close contact with the core pin 52 by cooling, so that the mold release from the injection cavity mold 42 can be performed relatively smoothly. And the mold release failure of the preform 1 does not occur. Further, since the core pin 52 is not pulled out in the injection molding section 14, even if the preform 1 is released at a high release temperature, the lower end of the preform 1 is rolled up together with the core pin 52. Also does not occur.

Note that the mold clamping state of the injection core mold 50 and the neck cavity mold 60 with respect to the preform 1 from which the injection cavity mold 42 has been released is determined by the return spring 74.
Accordingly, the core fixing plate 56 and the neck pressing plate 65 are kept in close contact with each other, and thus are maintained. The mold-clamped state of the injection core mold 50 and the neck cavity mold 60 is maintained until the injection core mold 50 is driven to be released from the preform take-out section 16 through the subsequent preform 1 transporting step. Therefore, the injection core mold 50 and the neck cavity mold 50
While the mold clamping state is maintained, the preform 1 can be cooled.

(Conveying Step of Preform 1) To convey the preform 1 from the injection molding section 14 to the preform take-out section 16, the rotary actuator 32 is driven to rotate the rotary plate 30 as the first circulating conveying section. Is rotated by 180 °. In the preform 1 transporting step, the preform 1 can be continuously cooled by the refrigerant circulating through the injection core mold 50 and the neck cavity mold 60.

When the preform 1 is released from the mold at a high temperature, crystallization occurs due to insufficient cooling, and the wall surface of the preform 1 becomes opaque. In particular, when a transparent container is formed using PET. Is a fatal drawback.
According to experiments performed by the present inventors, it has been found that crystallization and opacity of the preform 1 due to insufficient cooling are more remarkable on the inner wall side of the preform 1. This is due to the fact that the contact area with the mold is smaller on the inner wall side of the preform 1, and the inner wall is less cooled than the outer wall. Further, as in the prior art, the injection cavity mold 42 and the injection core mold 50 are preformed in the injection molding section.
This is because when the mold is further released, the inner wall side of the preform 1 has a smaller heat radiation area, and heat is stored inside the preform 1, so that the inner wall side is less cooled than the outer wall.

In this embodiment, even if the preform 1 is released from the injection molding section 14 at a relatively high temperature, the preform 1 is continuously cooled by the injection core mold 50 and the neck cavity mold 60 in the subsequent transport step. can do. In particular, since the inner wall of the preform 1 can be continuously cooled by the core pins 52 of the injection core mold 50,
Crystallization and opacity due to insufficient cooling can be reliably prevented. Further, the neck portion 2 having a large heat capacity due to its large thickness and easy to crystallize can be cooled by the neck cavity mold 60 to prevent crystallization.

(Step of cooling preform in preform take-out section 16) Even after the preform 1 has been carried into the preform take-out section 16, the mold clamping state of the injection core mold 50 and the neck cavity mold 60 to the preform 1 is maintained. As a result, the preform 1
Can be cooled. At this time, in the injection molding section 14, even if the mold clamping cylinder 28 is driven to lower the upper mold clamping plate 22 for injection molding of the next preform, the above-described mold clamping state in the preform take-out section 16 is obtained. Is maintained, the cooling of the preform 1 can be continued.

(Release Step of Neck Cavity Mold 60 from Injection Core Mold 50) The cooling of the preform 1 by the core pins 52 of the injection core mold 50 prevents crystallization caused by insufficient cooling of the inner wall of the preform 1. A cooling time sufficient to prevent deformation of the ejected preform 1 is sufficient, and conversely, if the preform 1 is overcooled by the core pin 52, it becomes difficult to pull out the core pin 52. Therefore, in the preform take-out section 16, first, the injection core mold 50 is driven to be relatively released from the preform 1. In the present embodiment, the neck cavity mold 60 holding the preform 1 is driven to release from the injection core mold 50.

The release of the neck cavity mold 60 is performed by the pressurizing force of the return spring 74 and the neck pressing plate 6 maintained in close contact with the core fixing plate 56.
5 is driven downward by the neck release drive unit 80. First cylinder 82 of neck release drive 80
Is driven, the first piston rod 82a, the first elevating plate 86, the pressing drive rod 88, and the driven rod 68
6 and FIG. 10, the neck fixing plate 64 is pressed by the neck pressing plate 65 to be driven downward. At this time, preform 1
Since the neck portion 2 is held by the neck cavity mold 60, the preform 1
And it is driven down together with the neck cavity mold 60. Therefore, the injection core mold 50 is released from the preform 1 by the relative release driving of the neck cavity mold 60 and the injection core mold 50.

An injection core mold 5 for this preform 1
The release stroke of 0 does not completely release the core pin 52 from the open end of the preform 1 for the subsequent transport of the preform 1 as in the conventional case. Any amount may be used as long as a gap is formed between the inner wall and the air. Therefore, the release stroke of the injection core mold 50 depends on the angle of the extraction taper formed on the core pin 52 and the inner wall of the preform 1, and the greater the extraction taper angle, the smaller the amount of release stroke. Thus, the injection core mold 50
Of the first cylinder 8
2, the height of the injection molding device can be reduced, and by reducing the overall height of the injection molding device, it is advantageous in terms of transportation and installation of the device.

(Step of taking out preform 1 at take-out section 16) The preform 1 has a neck portion 2 having a pair of split dies 6
Since the preform 1 is held by the neck cavity mold 60 composed of 2a and 62b, the preform 1 is taken out by releasing the neck cavity mold 60.
For this purpose, the second cylinder 1 of the split mold opening drive unit 100
02 is driven. The driving force of the second cylinder 102 is controlled by the second piston rod 102a, the second lift plate 10
6 to the split opening cam 108. As the split mold opening cam 108 is driven to move downward, its tip is inserted into a wedge hole 64d formed in the pair of split plates 64a and 64b as shown in FIG.
By driving b to open, the pair of split dies 62a and 62b are opened. At this time, even if one split mold 6
Even if the neck portion 2 of the preform 1 moves closely to the 2a and 62b, if the core pin 52 of the injection core mold 50 remains in the preform 1, the side of the preform 1 can be moved. The movement in the direction is regulated, and the preform 1 can be reliably dropped downward.

In the state before the split mold opening cam 108 is driven to descend, the tip thereof stops within the range of the thickness of the upper mold clamping plate 22 in order to avoid interference during the rotational driving of the rotating disk 30. Must be. On the other hand, the neck fixing plate 64 driven to be opened by the split opening cam 108 is
Since it is located farthest from the turntable 30, the downward stroke of the split opening cam 108 becomes longer. In this embodiment,
The second cylinder 10 for driving the split opening cam 108
2 is fixed to a first elevating plate 86 driven by a first cylinder 82, and before the split mold opening cam 108 is driven, the first
Since the lifting plate 86 is driven to descend, the substantial downward stroke of the split mold opening cam 108 can be shortened. Thus, the installation height of the second cylinder 102 can be reduced, and the overall height of the injection molding machine can be reduced, thereby providing an advantageous apparatus in terms of transportation and installation.

After the step of taking out the preform 1 is completed, the first and second cylinders 82 and 102 are returned to the initial state. As a result, the neck pressing plate 65 is brought into close contact with the core fixing plate 56 by the return spring 74, and the injection core mold 50 and the neck cavity mold 60 can be returned to the mold clamped state in preparation for the next preform injection molding.

The above-described cooling and releasing steps in the preform take-out section 16 are completed until the injection molding of the next new preform is completed in the injection molding section 14, in other words, within the injection molding cycle time. It should just be.
The cooling time of the preform 1 depends particularly on the thickness of the body of the preform 1, and it is necessary to secure a longer cooling time as the thickness of the preform 1 increases. In the present embodiment, the adjustment of the cooling time is performed in addition to the adjustment of the cooling time in the injection molding section 14 and the preform removal section 1.
6 can be adjusted by setting the release timing of the injection core mold 50. Therefore, while increasing the mold release temperature in the injection molding section 14 to shorten the injection molding cycle,
Since the cooling time can be easily adjusted, a highly versatile preform injection molding station can be provided.

After the injection molding of the preform 1 in the injection molding section 14 is completed, the rotary plate 30 is rotated by 180 ° by the rotary actuator 32 to thereby make the two parts 1
The injection core mold 50 and the neck cavity mold 60 are exchanged for 4 and 16. In this embodiment,
The rotary actuator 32 is constituted by a reversible rotary transport unit in which the rotational transport direction is changed each time. Therefore, even if the cooling pipe for circulating the refrigerant is connected to the injection core mold 50 and the neck cavity mold 60 which are rotated and conveyed, the cooling pipe is not twisted more than one rotation. Therefore, the connection of the cooling pipe to the mold can be performed without using a rotary connector or the like, and the configuration is not complicated.

At this time, since the preform 1 is given a uniform temperature or an appropriate temperature distribution for the above-described reason, a bottle having a desired thickness can be formed. Further, whitening and crystallization of the bottle are prevented from occurring, and a highly transparent bottle can be formed. The present invention is not limited to the hot parison blow molding method described above, but may be applied to a so-called cold parison blow molding method in which the preform 1 is once returned to room temperature, and then heated and blow molded. Of course, it can be applied.
Also in this case, there is an effect that the injection molding cycle time of the preform can be shortened.

(Transfer Station 200) Next, the structure and operation of the transfer station 200 will be described with reference to FIGS.
This will be described with reference to FIGS. FIGS. 12 to 15 do not correspond to the embodiment of FIG. 1, but show a mechanism corresponding to the embodiment of FIG. FIG. 21 shows that the above-mentioned simultaneous molding numbers N and n are:
FIG. 12 shows a case where N = 6 and n = 2, respectively.
Each mechanism of the transfer station 200 shown in FIG. 15 to FIG. 15 is simultaneously transferring n = 2 preforms 1. In addition,
The case of transferring n = 1 preforms 1 is exactly the same as the case of n = 2 except that there is no transfer pitch conversion described later.

This transfer station 200 is roughly divided into
A receiving and lowering mechanism 210 for receiving and lowering the preform 1 taken out from the take-out section 16 of the preform molding station 10, and then turning the preform 1 upside down so that the receiving section 3 of the blow molding station 300
04, and a reversing / transfer mechanism 230 for passing the image data to the receiving device.

(Receiving / Descent Mechanism 210) FIGS. 12 and 13 show the rising position of the receiving / lowering mechanism 210,
The lowering positions are shown respectively. The receiving / lowering mechanism 210 includes a bottom holding portion 214 for holding the bottom 3 of the preform 1 and a neck lower holding portion 2 for supporting the support ring 2 a present at the lower end of the neck 2 of the preform 1.
18. The bottom holding portion 214 is provided with a rod 2 of the first lifting / lowering drive device 212 including an air cylinder or the like.
12a, and can be moved up and down between a raised position shown in FIG. 12 and a lowered position shown in FIG. This lifting stroke b is shown in FIG.

On the other hand, the neck lower holding portion 218 can move up and down together with the bottom holding portion 214, and can move horizontally by a horizontal movement stroke a shown in FIG.
Therefore, the first slide portion 220 is slidably disposed along the rail 222. The first slide portion 220 is driven in the horizontal direction by a rod 216a of a first advance / retreat drive device 216 composed of an air cylinder or the like. The neck lower holding portion 218 has a small-diameter shaft portion 218a in its lower region.
And a large-diameter shaft portion 218b in the upper region, and the small-diameter shaft portion 218a penetrates the stopper member 220a fixed to the first slide portion 220. The small-diameter shaft portion 218 protruding downward from the stopper member 220a
A flange 218c is fixed to a lower end portion of a.
Further, a spring 218d is disposed on the small diameter shaft portion 218a protruding above the bottom holding portion 214. Since the spring 218d is disposed between the bottom holding portion 214 and the large-diameter shaft portion 218b, the large-diameter shaft portion 218d is pressed upward via the spring 218d as the bottom holding portion 214 is raised, and the neck 218d is pressed. The lower holding part 218 can be raised. Also, the first forward / backward driving device 2
When the 16 is driven, this horizontal driving force is transmitted to the shaft portions 218a and 218b via the first slide portion 220, so that the neck lower holding portion 218 can be slid horizontally. This slide movement stroke a is shown in FIG.

Next, the operation of the receiving / lowering mechanism 210 will be described with reference to FIG. 4, FIG. 12, and FIG. At the ejection section 16 of the preform molding station 10, before the neck cavity mold 60 is opened and driven, the bottom holding section 214 and the neck lower holding section 218 are arranged at the positions shown in FIG. In the state shown in FIG. 12, the upper limit position of the neck lower holding portion 218 is positioned by the flange 218c at the lower end abutting the stopper member 220a. Also, the bottom holding part 21
No. 4 is stopped at a position where the neck lower holding portion 218 reaches the upper limit position and compresses the spring 218d to further rise. At this time, the neck lower holding portion 21
Reference numeral 8 is set at a position retracted rightward in FIGS. 4 and 12 from a position immediately below the support ring 2a of the preform 1. After this, the neck cavity mold 60
Is driven to open, the preform 1 falls downward, and its bottom 3 is received by the bottom holding section 214. At this time, as shown in FIG. 12, the preform 1 is not completely detached from the core pin 52, and a part of the core pin 52 remains inserted, so that the preform 1 can maintain an upright state.

Thereafter, the first advance / retreat drive device 216 is driven, and the neck lower portion 218 is moved leftward in FIG. 12 by the stroke a (see FIG. 4). As a result, the neck lower holding portion 218 is disposed at a position immediately below the support ring 2a of the preform 1.

Thereafter, the first lifting / lowering drive device 212 is driven to pull in the rod 212a, and the lowering drive of the bottom holding portion 214 is started. In the initial state of the lowering drive, the neck lower holding portion 218 is stopped at the upper limit position while the spring 218d elastically returns. Accordingly, in the initial state of the lowering drive, the support ring 2 a of the preform 1 is placed on the neck lower support 218 while the bottom holding portion 214 is separated from the bottom 3 of the preform 1. Thereafter, the first lifting drive 212 is driven continuously, so that the preform 1 is lowered while the support ring 2a is held only by the neck lower holding portion 218. The bottom holding portion 214 and the neck lower holding portion 21
It is preferable to use a member having a low heat transfer property, for example, a synthetic resin or the like, for a portion in which the preform 1 contacts the portion 8. The downward conveyance of the preform 1 supported by the neck lower holding portion 218
This is continued until the position shown in FIG. 13 is reached.

(Reversing / Delivering Mechanism 230)
The configuration of the delivery mechanism 230 will be described with reference to FIG. 4 and FIGS. This reversing / delivery mechanism 230
Corresponds to the simultaneous blow molding number n = 2 in the blow molding section 310 shown in FIG.
(See FIG. 14). Each neck holding mechanism 232
It has a pair of openable and closable neck holding members 234 for holding the neck 2 of the preform 1. The two neck holding mechanisms 232 are mounted on a support 236 as shown in FIG. 15, and the support 236 is connected to a rod 238a of a second lifting / lowering drive device 238 composed of an air cylinder or the like. . Thereby, the two neck holding mechanisms 2
32 is a vertical movement stroke e shown in FIG. 4 (see FIG. 4)
It can only be moved up and down. In order to smoothly move up and down, for example, two guide rods 240 are provided, and are guided by guides 242 (see FIG. 15).

As shown in FIG. 15, the second lifting / lowering drive device 238 and the guide portion 242 are connected to the second slide portion 2.
44. Further, a horizontal drive device 246 is provided for moving the second slide portion 244 along the arrangement direction of the N, for example, four preforms 1 simultaneously injection-molded by the injection molding portion 14. The horizontal driving device 246 moves the second slide portion 244 horizontally using, for example, a ball screw 246a. Further, the horizontal drive device 246 is mounted on a third slide portion 248, and a second advance / retreat drive device 250 for driving the third slide portion 248 forward / backward by the advance / retreat stroke c in FIG. 4 is provided. That is, as shown in FIG.
The rod 250 a of the forward / backward drive device 250 is connected to the third slide portion 248.

Further, an inversion driving device 252 for rotating the two neck holding mechanisms 232 by 180 ° about a horizontal axis is provided. FIG. 4 shows a 180 ° rotational movement stroke d of the reversing drive device 252. As a result, the preform 1 in the upright state with the neck part 2 facing upward is driven to be inverted to the inverted state with the neck part 2 facing downward.

Next, the operation of the reversing / delivery mechanism 230 will be described. As shown in FIG. 13, when the preform 1 reaches the lowered position, the neck holding mechanism 232 at the standby position shown by the chain line in FIG.
2 is rotated by 180 °. Further, a pair of neck holding members 234 are closed and driven by an opening / closing drive mechanism built in the neck holding mechanism 232, and the neck portion 2 of the preform 1 is driven by the pair of neck holding members 234.
Can be held. Thereafter, the inversion drive of the preform 1 is performed. Before that, in order to prevent the preform 1 from interfering with other members, the neck lower holding portion 218 is retracted to the right by the movement stroke a (see FIG. 4) from the state shown in FIG. By moving the third slide portion 248 to the left by the movement stroke c (see FIG. 4), the two neck holding mechanisms 232 are moved to the left. Thereafter, the preform 1 is rotated by 180 ° by the inversion driving device 252, so that the preform 1 reaches the position shown by the chain line in FIG. After that, the two neck holding mechanisms 232 are lowered by the stroke e (see FIG. 4) by the second lifting / lowering drive device 238, so that the receiving section 30 of the blow molding station 300 is moved.
The preform 1 can be placed on the transport member 330 arranged at the position 4. Thereafter, the neck holding mechanism 232 is driven to open and further moved by the vertical movement stroke e and the horizontal movement stroke c shown in FIG. 13 can be set to the standby position indicated by the chain line.

In the case of the embodiment shown in FIG. 21 where the number of simultaneous moldings is n = 2, n = 2 preforms 1 are simultaneously transferred. The two transferred preforms 1 have two receiving positions 260 shown in FIG.
At the transfer member 330. At this time, the pitch P2 when the neck holding mechanism 232 receives the two preforms 1 from the receiving / lowering mechanism 210 and the conveying member 33
This is different from the pitch P3 when the pitch is transferred to 0. This is because the variable pitch drive 2
This is because pitch conversion is performed by 54, and this point will be described later. In the case of FIG. 1 which is the embodiment apparatus of the simultaneous molding number n = 1, two receiving positions 260 shown in FIG.
The preform 1 is delivered to the conveying member 330 at an intermediate position of the preform 1. Therefore, every time one injection molding operation of the simultaneous molding number N = 4 is completed, one preform 1
Is repeated four times.

(Blow molding station 300)
The blow molding station 300 will be described with reference to FIGS. 1 to 4 and 16 to 20.

(Second circulating transport section 302 and receiving section 30)
4) The blow molding station 300 controls the transport member 330 circulated and transported by the second
It is sequentially circulated and transported to the receiving section 304, the heating section 306, the standby section 308, the blow molding section 310, and the bottle removing section 312. As shown in FIG. 1, the second circulating transport unit 302
It has four transport sprockets 320a to 320d,
For example, only the sprocket 320a is driven, and the other sprockets 320b to 320d are driven. An endless transport chain 322 is stretched over the four transport sprockets 320 to 320d. An endless drive member such as a chain can be constituted by a belt, for example, a V-belt, a toothed belt, and the like, and a rotary drive member such as a sprocket can be a pulley.

In the embodiment shown in FIG. 1, ten transport members 330 are fixed to the transport chain 322. This mounting structure is as follows.

As shown in FIG. 18, the transport member 330
It has a cylindrical fixing portion 332. On one side surface of the fixing portion 332, there are protruding portions 334a and 334b protruding above and below the transport chain 322. The transport chain 322 is formed by connecting the chains with hollow pins. A fixing pin 336 is inserted into a hollow portion of the hollow pin to prevent both ends thereof from falling off, so that the transport chain 322 and the upper and lower protrusions are formed. 334a and 334b are connected to each other.

The transport member 330 is fixed to the fixed portion 33.
The inside of the cylindrical body 34 via a bearing 340 inside the cylindrical part
2 is rotatably supported. And this cylindrical body 342
Functions as a mounting table 344 on which the end face of the neck portion 2 of the preform 1 in the inverted state is mounted. This cylinder 3
Further, a transport pin 346 is supported in 42.
A portion where the transfer pin 346 projects above the mounting table 344 is inserted into the neck portion 2 of the preform 1 so that the preform 1 can be supported in an inverted state. Therefore, the mounting table 344 and the transport pins 346
These constitute the support portion of the preform 1.

As shown in FIG. 16, three cam followers constituted by rollers and the like are supported by the transport member 330. The two cam followers 338 move while rotating along the inner trajectory when the transport member 330 is driven by the transport chain 322.
The remaining one cam follower 338 conveys while rotating along the outer trajectory. These three cam followers 338
324 or rail 326 for guiding the transfer
Is provided. As shown in FIG. 18, the two rails 326 arranged on both sides of the transport path are each formed in a U-shaped cross section, and the lower surface thereof is a cam surface 326a.
The rail 326 is projected so as to cover an upper area of the cam follower 338 so that the cam follower 338 is not separated from the rail 326. The rail 326 is disposed in the blow molding section 310.

On the other hand, in the transport path excluding the blow molding section 310, for example, as shown in FIG.
A transfer table 324 is provided below the transfer path. The upper surface of the transfer table 324 is a cam surface 324a. The rail 326 arranged in the heating unit 306 is a cam follower 3
38 is disposed so as to cover the upper part of the cam follower 338.
Is prevented from leaving the traveling path. If the carrier table 324 is provided in the blow molding section 310, the above structure is adopted because the extension rod and the blow core mold cannot be inserted into the preform 1 from below the preform 1.

Note that the cylindrical body 342 of the transport member 330 has
A rotation sprocket 348 is fixed. In this rotation sprocket 348, the preform 1
6, the preform 1 is rotated about its longitudinal axis.
6 will be described later.

The driving sprocket 320a moves by one pitch of the conveying member fixed at predetermined intervals to the conveying chain 322, and thereafter repeats the intermittent conveying operation in which the sprocket is stopped for a predetermined time. By receiving the preform 1 in an inverted state at the receiving section 304 of the blow molding station 300, the preform 1 is placed on the mounting table 344 of the transport member 330, and the transport pin 346 is connected to the neck portion thereof. 2 is inserted. Thereafter, when the driving sprocket 320a is rotationally driven, the transport sprocket 3a is rotated.
The transport chain 322 meshing with 20a to 320d moves, whereby the transport member 330 is moved by one pitch. By repeating this transport operation, the preform 1 received by the receiving unit 304 is carried into the blow molding unit 310 via the heating unit 306 and the standby unit 308, where the bottle 6 is stretch blow molded from the preform 1. Will be done. Further thereafter, the transport member 33
The bottle 6 mounted on the bottle 0 is conveyed to the bottle take-out unit 312, where the bottle 6 is taken out of the apparatus.

(Heating Unit 306) Next, the heating unit 306 will be described with reference to FIGS.

The heating section 306 is provided with the heating box cover 35.
The preform 1 is heated by radiant heat in the area covered by 0. As described above, in the apparatus of the present embodiment, the injection core mold 50 is released from the preform 1 by the injection core mold 50 while the preform 1 is being conveyed to the take-out section 16 and at the take-out section 16. The preform 1 can be sufficiently cooled until the time when the preform 1 is cooled. Therefore, the preform 1 can be sufficiently cooled even with the hot parison method, and can be cooled to a temperature lower than the appropriate temperature for blow molding. Therefore,
In the apparatus of the present embodiment, the preform 1 is heated by a heating unit 306 provided in the blow molding station 300 until the temperature of the preform 1 reaches an appropriate temperature for blow molding.

The heating box cover 350 of the heating section 306
Inside, there are first to fourth rod-shaped heaters 352a to 352d constituting a first heater group arranged in a plurality at intervals in the axial direction of the preform 1. Each bar-shaped heater 3
52a to 352d are formed by, for example, an infrared heater,
The preform 1 extends in the heating box cover 350 along the transport direction of the preform 1. First and second rod-shaped heaters 35
Reference numerals 2a and 352b heat the preform 1 in particular near the bottom 3 by radiant heat by being surrounded by the light-collecting reflector 354a. On the other hand, the third and fourth rod-shaped heaters 3
Reference numerals 52c and 352d heat the radiant heat particularly around the body 4 of the preform 1 by being surrounded by the light-collecting reflector 354b. As shown in FIG. 19, the reflection plate 356 is located at a position facing the first to fourth rod-shaped heaters 352 a to 352 d with the conveyance path of the preform 1 as a boundary.
Is arranged.

Further, as shown in FIG. 19, fifth and sixth rod-shaped heaters 352e and 352f constituting a second heater group are arranged on both sides of the preform 1 conveyance path. The vertical height position of each of the bar-shaped heaters 352e and 352f is a position facing a region near the neck portion 2 of the preform 1 stretched and oriented by the blow molding unit 310. The fifth and sixth rod-shaped heaters 352
The region heated by e and 352f is a region directly below the neck portion 2 when the preform 1 is in the upright state, and this region is hereinafter referred to as a neck lower region 4a.

The neck lower region 4a is a region corresponding to a shoulder portion of the blow-molded bottle 6. Therefore, when the preform 1 is arranged in the blow mold 378, the neck lower region 4a is arranged at a position closest to the blow cavity surface. As a result, the neck lower region 4a tends to be thick because of a low horizontal axis orientation ratio. However, by sufficiently heating the neck lower region 4a, it is possible to form a desired thin wall. For this reason, in the present embodiment, the fifth and sixth rod-shaped heaters 352e and 352f are arranged at positions opposite to the neck lower region 4a of the preform 1, and the radiation surface of this heater is located at the lower part of the neck than other heaters. It is arranged close to the region 4a.

The heating box cover 35 of the heating section 306
As shown in FIG. 20, two sprockets 360a and 360b are arranged in the inside of the shaft 0, and a rotation drive chain 358 is stretched over the sprockets 360a and 360b. The rotation driving chain 358 is connected to the conveying member 33 carried into the heating unit 306.
The sprocket 348 engages with the zero rotation sprocket 348. With this structure, when the rotation driving chain 358 is driven, the rotation sprocket 348 rotates, and this rotational force is transmitted to the preform 1 via the cylindrical body 342, and the preform 1 is driven to rotate. Become.

Therefore, when the preform 1 is carried into the heating unit 306, the bottom 3 and the body 4 of the preform 1
Is a rod-shaped heater 352 disposed on one side of the transport path.
a to 352e and the reflection plate 356 disposed on the other side, respectively, receives the radiant heat, and receives substantially uniform radiant heat in the circumferential direction by rotating the preform 1, thereby uniformly heating in the circumferential direction. be able to. Further, the neck lower region 4a of the preform 1 is sufficiently heated by the fifth and sixth rod-shaped heaters 352e and 352f arranged close to both sides of the preform 1 conveyance path. The heating is performed almost uniformly in the circumferential direction.

Here, as shown in FIG. 20, when the conveying direction of the preform 1 is A, the traveling direction of the rotation driving chain 358 at a position where the conveying member 330 meshes with the rotation sprocket 348 is A. The direction is set to the direction B opposite to the direction. The reason is as follows.

That is, if the transport chain 322 and the rotation drive chain 358 move in the same direction A at the same speed, the rotation sprocket 348 and the rotation drive chain 358 on the transfer member 330 side Does not change, and the preform 1 does not rotate at all. Even when only the transport speed of the transport chain 322 and the rotation drive chain 358 is changed, the rotation of the preform 1 becomes extremely slow or reversely depending on the magnitude of the speed. In these situations, the rotation drive chain 358 is connected to the transport chain 322.
This does not occur if the motor is rotated at a higher speed, but such a high-speed rotation is generally not preferable in terms of moment. If the preform 1 is slightly bent when rotated at a high speed, the bending is further increased by receiving a strong moment, which causes uneven temperature during heating and adversely affects the wall thickness distribution of the bottle 6. .

Therefore, as shown in the embodiment shown in FIG. 20, by setting the traveling directions of the transport chain 322 and the rotation driving chain 358 to be opposite to each other, when the preform 1 is transported in the A direction, The rotation direction is always
Is constant in the direction of arrow C, and the above-mentioned problem is solved.
When the preform 1 is transported, the rotation speed is increased more than the rotation speed at the stop position of the preform 1.

Further, in this embodiment, while the preform 1 is positioned in the heating zone inside the heating box cover 350, the total number of rotations of the preform 1 to be rotated is set to substantially an integer. In the case of this embodiment, while the preform 1 is located in the heating zone, as shown in FIG. 20, each distance L1, L2, L3 (L1 + L2 + L
3 = the time of moving the heating zone length L) and the time of stopping at the two positions shown in FIG. In addition, L1 is a distance by which the preform 1 carried into the heating zone is transported to the first stop position, L2 is a distance by which the preform 1 is transported between the two stop positions, and L3 is a heating zone from the second stop position. The transport distance until the product is unloaded from the printer is shown. In the present embodiment, by setting the number of times the preform 1 rotates to be substantially an integer number of times over the transport time and the stop time, the radiant heat from both sides of the transport path of the preform 1 is reduced. The preform 1 can be received substantially uniformly in the direction, and temperature unevenness in the circumferential direction of the preform 1 can be prevented.

Further, according to the present embodiment, the heating unit 30
The operation of heating the preform 1 in 6 can be performed before the temperature difference between the inner wall and the outer wall of the preform 1 is sufficiently reduced. That is, in this embodiment, in the preform molding station 10, the preform 1 is sufficiently cooled from the inner wall side by the injection core mold 50. Therefore, the preform 1 taken out by the take-out section 16 has a low inner wall temperature and a high outer wall temperature. However, this preform 1
Is not immediately carried into the heating unit after a short carrying period as in the case of a device called a so-called hot parison system or a one-stage system. After the transport operation by feeding, the wafer is carried into the heating unit 306. Thus, after the preform 1 is released from the mold, the preform 1 is carried into the heating unit 6 after a sufficiently long cooling time as compared with the so-called one-stage apparatus. For this reason, the temperature difference between the inner and outer walls of the preform 1 can be sufficiently reduced. The point that there is no temperature difference between the inner and outer walls is the same as that of a device called a so-called cold parison method or a two-stage method, but even in comparison with this device, the present embodiment retains heat during injection molding. Since the bottle 6 can be blow-molded more than the parison 1, it is excellent in that less heat energy can be given and energy can be saved.

Furthermore, according to this embodiment, the preform 1 cooled to a temperature lower than the appropriate temperature for the blow molding (but sufficiently higher than the room temperature) is controlled to be heated, so that the preform temperature can be stabilized for each molding cycle. Thus, it is possible to reduce the temperature variation when a plurality of injection-molded preforms 1 are blow-molded a plurality of times at the same time. In the apparatus of the present embodiment, the transport pitch when the preform 1 is transported by the second circulation transport unit 302 is maintained at a constant pitch. On the other hand, in a conventional cold parison type or two-stage type molding machine, the conveying pitch when the preform is heated by the heating unit is reduced, and when the preform is carried into the blow molding unit, the conveying pitch is increased. ing. This is because preforms that have been completely cooled down to room temperature must be heated to the appropriate temperature for blowing, so that the total number of preforms that can be introduced into the heating section is maximized to save space in the equipment. is there. On the other hand, in the blow molding section, when molding a plurality of pieces at the same time, the distance between the preforms must be at least larger than the maximum width of the molded product. In addition, the preform before being carried into the blow molding unit and the preform after having been carried out must wait outside the blow mold clamping device of the blow molding unit. For this reason, in the conventional one-stage molding machine, the conveying pitch must be changed in the middle, and the apparatus is complicated.

On the other hand, the apparatus of this embodiment blows the bottle 6 from the preform 1 while holding the heat during the injection molding in the injection molding section 14, so that the heating section 30
The heating energy to be applied in 6 is slightly smaller than in the case of the two-stage system. Therefore, even if the total number of the preforms 1 arranged in the heating section 306 is not increased, the preforms 1 can be sufficiently reheated to the appropriate blow temperature, and there is no need to change the transport pitch midway.

(Standby unit 308) As shown in FIG. 1, in the middle of the transport path between the heating unit 306 and the blow molding unit 310, one preform performed in a normal transport sequence in which intermittent driving is performed. 1 is stopped by the standby unit 308. By providing the standby portion 308, the temperature distribution of the synthetic resin preform 1 having poor thermal conductivity can be reduced. Heating unit 30 in the apparatus of the present embodiment
6, the heating of the preform 1 is usually performed by radiant heat from the outer wall surface side. For this reason, the temperature of the inner wall of the preform 1 is lower than the temperature of the outer wall. In the present embodiment, the preform 1 is stopped at the standby unit 308 at least once after the preform 1 is carried out from the heating unit 306 and before it is carried into the blow molding unit 310. The difference can be reduced, and the blow moldability of the bottle 6 can be stabilized.

Within the temperature relaxation time in the standby unit 308,
The temperature of the preform 1 can be positively adjusted.
By actively controlling the temperature of the preform 1 in the standby unit 308, a temperature distribution that cannot be obtained by simply heating the preform 1 while rotating it in the heating unit 306 can be obtained.

As shown in FIG. 23, the temperature control member disposed in the standby portion 308 is inserted into the inside of the preform 1 from below the preform 1, and extends from the inner wall side over the temperature control region S. A temperature control core 400 for controlling the temperature can be obtained. The temperature control core 400 has a first temperature control core 402 that controls the temperature of the neck lower region 4a of the preform 1 from the inner wall side. Further, the temperature control core 400 has a second temperature control core 404 for controlling the temperature of the body 4 excluding the neck lower region 4a. As described above, the neck lower region 4a
Needs to be adjusted to a higher temperature than other areas,
In the case of FIG. 23, the first temperature control core 402 is larger in diameter than the second temperature control core 404. Alternatively, a layer made of a material that emits heat rays having a wavelength that is easily absorbed by the molding resin material (for example, PET) of the preform 1 may be used as the first temperature control core 4.
02 may be coated.

The temperature control member may be a temperature control pot 410 having a cylindrical portion disposed around the preform 1 as shown in FIG. At this time, the temperature control pot 410 is placed on the heat insulating material 412 in the axial direction of the preform 1.
Blocks 414a-414d zoned via
Since each block 414a to 414d has an independent temperature control fluid passage 416, the temperature is controlled independently in each zone. Since the temperature control pot 410 can be disposed so as to cover the preform 1, a stepwise temperature distribution in the preform axial direction can be reliably obtained. Thus, for example, the temperature of the neck lower region 4a can be adjusted to a high temperature, and the temperature of the bottom portion 3 can be adjusted to a low temperature. Also, as shown in FIG. 24, air is introduced into the preform 1 from the direction of the arrow 420 to apply an internal pressure to the preform 1 so that the outer wall of the preform 1 and the blocks 414a to
414d to control the temperature.

Further, as a temperature control member of this type, it extends along the axial direction of the preform 1 at one or a plurality of locations in the circumferential direction of the preform 1 and adjusts the temperature distribution in the circumferential direction of the preform 1. It can be a member to be applied. For example, as shown in FIG. 25, a pair of cooling members 430 are arranged along the axial direction of the preform 1, for example, on both side surfaces of the preform 1, and are attached to the body side wall of the preform 1 by an air cylinder 432 or the like. Contact can also be made. This gives a temperature distribution in the circumferential direction of the preform 1,
For example, as shown in FIG. 26, it is possible to sufficiently secure the thickness of the flat bottle 6 in a region where the horizontal axis stretching ratio is high. Such measures can be applied not only to a flat container but also to, for example, a square container. When the temperature distribution is provided in the circumferential direction of the preform 1, the temperature distribution is not limited to the one in which the cooling member is brought into contact, and the one in which the heating member is disposed in proximity may be used.

(Blow Molding Section 310) The blow molding section 310 is provided on both sides of the preform 1 conveyance path.
It has two blow fixing plates 370 fixed on the machine base 8. As shown in FIG. 4, the two blow fixing plates 370
Between them, for example, four tie bars 372 are bridged. Two blow-type clamping plates 374 are provided between the blow fixing plates 370 and move horizontally along the four tie bars 372. The two blow-type clamping machines 374 are provided with a blow-type clamping mechanism 37 composed of, for example, a hydraulic piston disposed on the blow fixing board 370.
6, the opening / closing drive is performed symmetrically on both sides of the vertical line.

The two blow mold clamping plates 374 have a pair of split molds 378 constituting a blow cavity mold 378.
a, 378b are fixed. In the case of the apparatus of the embodiment shown in FIG. 1, since the simultaneous molding number n = 1, a cavity for one bottle is formed in the pair of split molds 378a and 378b. In the case of the embodiment apparatus shown in FIG. 21, since the number n of simultaneous moldings is 2, a pair of split molds 378a, 3
At 78b, a cavity for two bottles is formed.

At an intermediate position between the upper two tie bars 372, a cylinder fixing plate 380 is fixed, and a bottom driving cylinder 382 is mounted on the cylinder fixing plate 380. The bottom mold driving cylinder 382 drives the bottom mold 384 to move up and down.
In this embodiment, the bottle 6 is replaced with the preform 1 in the inverted state.
Is blow-molded, so that the bottom mold 384 can be moved up and down at a position above the preform 1.

As described above, according to the present embodiment, the injection molding section 14 of the preform molding station 10 injection-molds the preforms of the simultaneous molding number N = 4 to increase the production efficiency while increasing the blow molding section 310. Then, the simultaneous molding number n =
The operation rate of the blow cavity mold 378 can be increased by molding the bottle 6 from one preform. In addition, by reducing the number of cavities of the relatively expensive blow cavity mold 378 in the mold, the cost of the consumable mold can be reduced. Furthermore, according to the present embodiment, the preform molding station 1
After sufficiently cooling at 0, the preform 1 is released from the mold. After that, a sufficient cooling time is given to alleviate the temperature difference between the inner and outer walls of the preform 1, and then the preform 1 is heated to an appropriate blow temperature. Therefore, the uniformity of the temperature distribution of the retained heat of the preform 1 can be improved, and the stability of blow molding can be significantly improved.

(Bottle take-out section 312) Second circulation / transport section 3
As shown in FIGS. 1 and 4, a bottle take-out unit 312 is arranged in the middle of the conveyance path of the conveyance member 330 conveyed by the second member 02 and between the blow molding unit 310 and the receiving unit 304. The bottle removing unit 312 is, for example, a neck holding mechanism 2 employed in the reversing / delivery mechanism 230
A neck holding mechanism 390 having the same structure as that of the neck holding mechanism 390 is provided. The neck holding mechanism 390 is used for the bottle 6 in an inverted state.
Is held by a pair of holding members. As shown in FIG. 3 and FIG.
It has a lifting drive 392 that drives the 90 up and down, and a reversing drive 394 that reverses the neck holding mechanism 390 at a rotation angle of 180 °. When the neck holding mechanism 390 is raised by the lifting / lowering drive device 392, the neck portion of the bottle 6 is detached above the transport pins 346 of the transport member 330. Then, the bottle 6 is turned upright on the side of the machine base 8 by rotating the neck holding mechanism 390 by 180 ° by the reversing drive device 394, and thereafter, the chuck piece of the neck holding mechanism is opened and driven. Thus, the bottle 6 can be discharged outside the apparatus.

(Case where Simultaneous Molding Numbers N = 6, n = 2) FIG. 21 is a plan view of the embodiment apparatus in which the simultaneous molding numbers N and n are set as described above. The difference between the embodiment shown in FIG. 21 and the embodiment shown in FIG. 1 is as follows.

First, the blow-molding section 310 simultaneously performs two bottles 6 from the preform 1 with the simultaneous molding number n = 2.
In order to blow mold the blow cavity mold 47,
It has two blow cavities arranged at an arrangement pitch P3. The arrangement pitch of the transport members 330 transported and driven by the second circulating transport unit 302 is the same as the arrangement pitch P3 of the blow cavities in the blow molding unit 310. Further, the transport member 3 fixed to the transport chain 322 constituting the second circulating transport section 302
The total number of 30 is 20, which is a multiple of the case of the embodiment apparatus shown in FIG. In the heating unit 306, 2 × n = the number of preforms 1 for two blow moldings
The four preforms 1 are stopped.
In the standby section 308, n = 2 preforms 1 for one blow molding are made to wait. Note that the transport chain 322 and the transport member 330 used in the embodiment apparatus of FIG. 21 are the same as those of the embodiment apparatus shown in FIG. 1, and only the mounting position and the mounting pitch of the transport member 330 with respect to the transport chain 322 are different. Has changed.

In the embodiment shown in FIG. 21, in the transfer station 200, the preform 1 of the simultaneous molding number n = 2 in the blow molding section 310 is simultaneously transported. For this reason, the transfer pitch conversion operation described with reference to FIG. 22 is required. In the figure, six preforms 1 that are simultaneously injection-molded in the injection molding section 14 of the preform molding station 10 are shown as preforms 1a to 1f, respectively. In FIG. 22, the state shown in the first column on the right side shows the arrangement pitch of the preforms 1 injection-molded at the preform molding station 10. Each preform 1 at this time
Are the same as the arrangement pitch P1 of the core pins 52 of the injection molding unit 14. The state in the second column of FIG.
Shows the state before the preform 1 is received. The arrangement pitch of the preform 1 in this case is also the pitch P1. The third column of FIG.
0 shows a state where two preforms 1 have been received by the receiving unit 304. The transfer of the two preforms 1 is performed by two pairs of neck holding members 234 shown in FIG.
This is performed using The arrangement pitch of the preforms 1 received by the receiving unit 304 is the same as the arrangement pitch P3 of the blow molding unit 310.

Here, when the two preforms 1 are transferred by the pair of neck holding members 234 in the transfer station 200, first, for example, the first and fourth preforms 1a and 1d are held. That is, the two preforms 1a and 1d are held with the two preforms 1b and 1c skipped. Therefore, the arrangement pitch P2 of the neck holding members 234 at this time is P2 = 3 × P
It is 1. The pitch conversion from the pitch P2 to the pitch P3 is performed by changing the arrangement pitch of the two neck holding mechanisms 232 by driving the pitch variable driving device 254 shown in FIG. Hereinafter, similarly, by transferring the second and fifth preforms 1b and 1e, and then simultaneously transferring the third and sixth preforms 1c and 1f, the six preforms 1 simultaneously injection-molded can be obtained. The transfer operation will be completed.

It is to be noted that the simultaneous molding number N, n is defined as N = 4, n
In the case of = 2, the transfer operation in the transfer station 300 is such that one preform is skipped and two preforms are simultaneously held while performing pitch conversion from the pitch P2 = 2 × P1 to P3. You can do it.

In the case of the apparatus of the embodiment shown in FIG. 21, the ratio (N / n) of the simultaneous molding numbers N, n is 3. According to the study of the present inventors, in the case of a general-purpose medium-sized container having a relatively small mouth of about 1 to 3 liters (the opening diameter of the neck portion 2 is about 28 to 38 mm), the ratio of the simultaneously molded pieces N and n is determined. , N: n = 3: 1
It turned out that setting to was optimal. The reason is as follows. The size of a preform for forming a general-purpose medium-sized container is in a substantially constant range, although there are some variables depending on the application. This is because the size of the preform is determined by the stretching ratio required for obtaining the stretching characteristics of the polyethylene terephthalate (PET) resin and the stretching ratio required for the stability of molding. The present inventors have found that the maximum thickness of the body 4 of the preform 1 used for a general-purpose medium-sized container is substantially in the range of 3.0 to 4.0 mm, although there is some variation depending on the use of various containers. It is known from research.

In general, the blow molding cycle time required for blow molding of a blow molding machine (the time required from carrying a preform 1 into the blow molding part 310 to carrying in the next preform 1) is approximately 3. 6 to 4.0 seconds.

In the case of this embodiment in which the preform 1 is cooled by the injection core mold 50 and then blow-molded after the mold is released from the injection cavity mold 42, such a general-purpose medium-sized preform is required. The time was reduced to about 3/4 compared to the conventional injection stretch blow molding machine, and it was found that the injection molding cycle time was about 10 to 15 seconds.

Therefore, when this injection molding cycle time (about 10 to 15 seconds) is T1 and the blow molding cycle time (3.6 to 4.0 seconds) is T2, almost T1: T2
= 3: 1, which proves that it is optimal to set the simultaneous molding numbers N and n according to the above-described ratio when efficiently molding a general-purpose medium-sized container. On the other hand, when molding a large container from a thicker preform, the injection molding cycle time is about 16 seconds or more.
N: n = 4: 1 can be set. Furthermore, when a small container is molded from a thin preform, the injection molding cycle time is shortened, so that N: n = 4: 2.
Etc. can be set. By setting N / n = 3, it is possible to set the injection molding cycle and the blow molding cycle suitable for molding a medium-sized container, which is considered to be the most demanded in the market, and to use the blow molding with less waste in the molding cycle. Machine can be realized.

(Ejection Mechanism During Preform Conveyance) In the apparatus of this embodiment, as shown in FIGS. 2 and 3, the preform drop opening 8a is opened in the area where the transfer station 200 of the machine base 8 is arranged. It is formed. The preform drop port 8a is provided with a shooter 8 provided inside the machine base 8.
b, and the shooter 8b communicates with a preform discharge port 8c opened on the side surface of the machine base 8.

In such a hot parison type blow molding machine, there are various cases where it is desired to stop conveying the preform 1 continuously molded in the preform molding station 10 to the blow molding station 300. For example, when starting up the entire blow molding machine, supply of the defective preform 1 to the blow molding station 300 should be prevented until the injection molding characteristics of the preform 1 are stabilized. Also, for some reason,
When an abnormality occurs in the blow molding station 300, it is desirable to stop the operation of only the blow molding station 300 and to continuously form the preform 1 without stopping the operation in the preform molding station 10. . This is because the preform molding station 10 has various heating sections, so once the power is reduced, a sufficient time is required for the startup time.

In this embodiment, the preform 1 which is continuously injection molded at the preform molding station 10
Before being transferred to the blow molding station 300 at the transfer station 200, the is discharged to the side of the machine base 8 through the above-described drop port 8a, shooter 8b, and discharge port 8c. The discharging operation of the preform 1 is performed by, for example, the pair of neck holding members 23 of the reversing / delivery mechanism 230.
After holding the preform 1 at 4, the preform 1 is, for example, horizontally moved to a predetermined position without performing a 180 ° reversing operation, and is set at a position facing the drop opening 8 a opened on the upper surface of the machine base 8. Then, the holding state of the neck holding member 234 only needs to be released.

In this embodiment, the preform 1 is set in the blow molding station 300 as the sequence control mode.
And a preform molding operation mode in which the preform 1 is not transferred to the blow molding station 300. These two modes are automatically switched when an abnormal situation is detected by, for example, a sensor, or switched by a manual switch by an operator, so that the normal bottle molding operation mode can be switched to the preform molding operation mode. it can. When the operation mode is switched to the preform molding operation mode, the operation at the transfer station 200 is switched to the operation for guiding the preform 1 to the drop port 8a as described above, and the preform 1 is transported to the blow molding station 300 side. Is forbidden.

Next, FIGS. 27 to 34 show an injection stretch blow molding apparatus according to another embodiment of the present invention.

As shown in the side view of FIG. 33 and the layout of FIG. 34, this injection stretch blow molding apparatus
A preform molding station 10, a transfer station 500, and a blow molding station 300 are arranged.

The preform molding station 10 has an injection molding section 14 at a position facing the injection device 12 shown in FIG.
Is provided, and an ejection portion 16 is opposed to the injection molding portion 14.
Are provided, and the injection molding section 14 and the removal section 16
Is circulated and conveyed by a rotary plate 30 as a first circulating conveyance unit that intermittently circulates and conveys the injection core mold 50 along a rotary conveyance path. In the preform molding station 10, the preform 1 is molded and taken out in a state where the opening of the neck 2 of the preform 1 is directed upward.

The blow molding station 300 is disposed on one side of the second circulating transport section 302 adjacent to the transfer station 500, forming a substantially rectangular transport path and circulating and transporting the molded article. A receiving unit 304 for receiving the preform 1, a heating unit 306 for heating the preform 1 disposed on one side of the second circulation transport unit 302 adjacent to one side of the receiving unit 304 in the transport direction, A second side adjacent to one side in which the heating unit 306 is disposed in the transport direction;
A blow molding section 310 for blow molding a preform disposed on one side of the circulation transport section 302;
0 and a discharge section (bottle take-out section) 312 for discharging a bottle disposed on one side of the second circulation transport section 302 adjacent in the transport direction. In the blow molding station 300, the second circulating transport unit 302
Thus, the preform 1 is conveyed in an inverted state with the opening neck portion 2 facing downward, and blow molding is performed.

These preform molding stations 10
Since the configuration of the blow molding station 300 is basically the same as that of the above-described embodiment, a description thereof will be omitted below, and a transfer station 500 having a configuration different from that of the above-described embodiment will be described below. In addition, the simultaneous molding number of the preform in the preform molding station 10 is six, the simultaneous blow molding number in the blow molding station 300 is two, and the preform molding pitch of the preform molding station 10 is The blow molding pitch of the blow molding station 300 is set large.

The transfer station 500 is, as shown in FIGS. 27 to 32, a preform molding station 10.
And a receiving / lowering mechanism 502 as a receiving mechanism for receiving and lowering the preform 1 taken out of the take-out section 16 in an upright state, and then turning the preform 1 upside down to receive section 304 of the blow molding station 300. And a reversing / delivery mechanism 504 as a reversing mechanism for delivering the preform 1 in an inverted state. The receiving / lowering mechanism 502 and the reversing / delivery mechanism 504 are parallelly movable on two guide rails 505 so as to be horizontally movable. It is installed in.

The receiving / lowering mechanism 502 is a gate cutter 506 such as an air nipper for cutting off the gate of the preform 1 conveyed to the take-out section 16 of the preform molding station 10 and taken out from the take-out section 16. Holding member 508 for receiving and holding preform 1
A first lifting / lowering drive device 510 for raising / lowering the gate cutter 506 and the holding member 508; and the gate cutter 506 and the holding member 5 together with the first lifting / lowering drive device 510.
08 is horizontally moved.

The gate cutter 506 is connected to the preform 1 at the take-out section 16 of the preform molding station 10.
6 are provided at the same interval as the molding pitch of the preform 1 along the arrangement direction of the preform 1, and the gates of the six preforms 1 are simultaneously inserted into the respective insertion holes 514,
The gate is cut off.

[0200] Six holding members 508 are provided along the arrangement direction of the preforms 1 in the take-out section 16 of the preform molding station 10, and simultaneously receive and hold the six preforms 1 taken out from the take-out section 16. It has become.

Further, since the preform 1 molded at the preform molding station 10 has the support ring 2a having an outer diameter portion larger than the body portion at the neck portion 2, the holding member 508 is formed of the support ring 2a. The preform 1 is held in contact with the lower surface,
The holding member 508 includes the support ring 2 of the preform 1
The horizontal movement is restricted by the preform insertion portion 516 that is slightly larger than the outer diameter of the lower portion adjacent to a.

Further, the holding member 508 is formed in two parts, each of which is supported by a pin 518 so as to be rotatable in the horizontal direction, and is urged in the closing direction by urging means such as a spring (not shown). Thus, the preform 1 can be opened and closed, can hold the preform 1 in the closed state, and can release the preform 1 in the open state.

Each holding member 508 is supported on a substantially U-shaped receiving member 520, and is blown from the preform molding pitch by the pitch converting mechanism 522 via the receiving member 520. The pitch is converted to the forming pitch.

The pitch conversion mechanism 522 includes
And five connecting rods 526 that slidably connect adjacent receiving members 520 to each other and slidably engage at intervals corresponding to the blow molding pitch. The piston rods are connected to the receiving members 520 located on the outside, respectively, and two pitch conversion drive cylinders 528 for sliding the three receiving members 520 on one side in the opposite direction to convert them to the blow molding pitch. It is configured.

Then, the two pitch conversion driving cylinders 5
28 drives the piston rod backward to move each receiving member 52
0 are in contact with each other, the preform molding pitch is maintained.
8, the receiving members 520 at both ends slide outward to move the connecting rod 52.
6 sequentially engages both ends and the receiving members 520 adjacent thereto, the adjacent receiving members 520 also slide, and the holding members 508 supported by the six receiving members 520 by the connecting rods 526 are converted into the blow molding pitch. Will be done.

The first lifting / lowering drive device 510 includes the holding member 5
08 and the gate cutter 506 are moved to the receiving height position A for receiving the preform 1 from the unloading section 16 and the conveying height position for descending from the receiving height position A and conveying the preform 1 to the reversing / transfer mechanism 504 side. B, three guide rods 530 that guide the gate cutter 506 and the holding member 508 so as to be able to move up and down, and drive the gate cutter 506 and the holding member 508 up and down along the guide rod 530. First lifting drive cylinder 532
It is composed of

Then, the gate cutter 506 and the holding member 508 are raised to the receiving height position A by the first raising / lowering drive cylinder 532, and the gate cutter 506 cuts off the gate and receives the preform 1 to perform preform 1 After receiving the preform 1, the preform 1 is lowered to the transport height position B, and the preform 1 is delivered to the reversing / delivery mechanism 504 at the transport height position B.

The first horizontal driving device 512 includes a holding member 5
Reference numeral 08 denotes a preform receiving position C (position in FIG. 29) located immediately below the take-out part 16, a gate cutter 506 denotes a gate cut position D (position in FIG. 30) immediately below the take-out part 16, and a holding member 508. Stops the reversing / transfer mechanism 504 from moving to the holding position E where the preform 1 is held. The first lifting drive unit 510 and the holding member 50
And reversing mechanism 50 including gate cutter 8 and gate cutter 506
2 has a first horizontal driving cylinder 534 for horizontally moving the first lifting / lowering driving device 510 along the two guide rails 505, and has a larger driving force than the first horizontal driving cylinder 534. When the holding member 508 is conveyed to the holding position E by the driving force of the first horizontal driving cylinder 534, the gate cutter 506 stops moving to the gate cutting position D against the driving force of the first horizontal driving cylinder 534. And a stop cylinder 560 for stopping the operation.

Then, the holding member 508 is moved from the preform receiving position C to the holding position E by the first horizontal driving cylinder 534, and the first horizontal driving cylinder 534 is driven from the holding position E to the gate cutting position D. The first horizontal drive cylinder 534 moves the gate from the gate cut position D to the preform receiving position C against the force by the halfway stopping cylinder 560.

The reversing / delivery mechanism 504 is provided in correspondence with the simultaneous molding number of the preform 1 and includes six neck holding mechanisms 536 arranged at a blow molding pitch.
Inversion driving device 5 for inverting the neck holding mechanism 536
38, a second lifting / lowering drive device 540 for raising / lowering the neck holding mechanism 536, a second horizontal driving device 542 for horizontally moving the neck holding mechanism 536 together with the second lifting / lowering drive device 540, and a positioning member 543 for the transport member And

The six neck holding mechanisms 536 each include a pair of openable and closable neck holding members 544 for holding the neck portion 2 of the preform 1, and the neck holding members 544.
And an opening / closing drive mechanism 546 that opens and closes.

[0212] The pair of neck holding members 544 are arranged in parallel, and are configured to hold the neck portion 2 of the preform 1 at the distal ends thereof.

The opening / closing drive mechanism 546 is provided for each of the two opening / closing rods 548 which are separately fixed to the pair of neck holding members 544 and supported so as to be slidable in parallel, and each of the two opening / closing rods 548. Synchronous mechanism 5 including two open / close drive cylinders 550 and a rack and pinion disposed between two open / close rods 548
52.

By driving the two open / close drive cylinders 550 in opposite directions, the synchronization mechanism 552 is driven.
While synchronizing the two opening / closing rods 548,
By sliding in the opposite direction, the pair of neck holding members 54
4 is opened and closed to hold and release the neck portion 2 of the preform 1.

The reversing drive device 538 has a reversing shaft 539 disposed horizontally and a reversing actuator 554 provided at an end of the reversing shaft 539. By rotating 546 180 degrees about the reversal axis, the preform 1 held in the upright state by the neck holding mechanism 536 is driven to be inverted to the inverted state.

The neck holding mechanism 536 inverted by the inversion driving device 538 includes an erect holding height position F for holding the neck portion 2 of the preform 1 held by the holding member 508 before the inversion, and a neck position after the inversion. It is positioned at an inverted standby height position G lower than the upright holding height position F.

The second lifting / lowering drive device 540 raises / lowers the neck holding mechanism 536 between the inverted standby height position G and the transfer height position H for transferring the preform 1 to the transport member 330 of the receiving section 304. The neck holding mechanism 53
6 has a second elevating drive cylinder 556 for elevating.

The second horizontal drive unit 542 includes a reversing / transfer mechanism 504, a receiving / holding position I where the neck holding mechanism 536 holds the preform 1 when the holding member 508 is at the holding position E, and a neck holding mechanism. Delivery position J for delivering the preform 1 to the transport member 330 according to 536
Between the receiving and holding position I and the transfer position J
Standby position K to wait until six transfer members are aligned in 04
The two guide rails 505
Along with the reversing / delivery mechanism 504 at the receiving and holding position I
A second horizontal drive cylinder 558 for horizontally moving and stopping between the second horizontal drive cylinder 558 and the transfer position J, and a second horizontal drive cylinder 55 having a greater driving force than the second horizontal drive cylinder 558.
8 is provided with a halfway stop cylinder 559 that stops at the standby position K against the driving force while moving the reversing / receiving mechanism 504 to the delivery position J.

Then, after the neck holding mechanism 536 holds the preform 1 at the receiving and holding position I of the preform 1, while the neck holding mechanism 536 is being moved to the delivery position J by the second horizontal drive cylinder 558, The reversing / delivery mechanism 504 is stopped at the standby position K by the piston rod of the halfway stopping cylinder 559 that has been driven in advance, and the receiving unit 304 is made to wait until the six transfer members 330 are aligned, and the transfer members 330 are aligned. At the stage, by releasing the driving force of the halfway stopping cylinder 560, the cylinder is moved to the delivery position J by the second horizontal driving cylinder 558,
After the delivery, the second horizontal drive cylinder 558 horizontally moves to the receiving and holding position I.

The positioning member 543 of the transport member has positioning recesses 562 that engage with the transport member 330 at six positions corresponding to the six transport members 330 that have been transported to the receiving section 16. At the stage where the neck holding mechanism 536 is moved to the delivery position J by the horizontal drive cylinder 558,
The positioning recess 562 of the positioning member 543 is
30 to ensure reliable positioning and secure delivery.

Next, the operation state of the transfer station 500 will be described mainly with reference to FIGS. 29 and 30.

First, the preform molding station 10
Preform 1 conveyed to take-out part 16 in
Is a neck cavity mold 60 at a position indicated by a solid line in the figure.
In an upright state.

The receiving / lowering mechanism 502 drives the halfway cylinder 560 in advance while being urged toward the holding position E by the driving force of the first horizontal driving cylinder 534, and moves horizontally to the gate cut position D. And the gate cutter 506 and the holding member 508 are at the transport height position B.

In this state, when the gate cutter 506 and the holding member 508 are raised to the receiving height position A by the first lifting drive cylinder 532, the gate of the preform 1 is moved from the gate insertion hole 514 to the gate cutter 5.
The gate inserted into the gate cutter 506 is inserted into the gate cutter 506 as shown in FIG.
It will be cut off by the drive of 06.

When the gate is cut, the holding member 508 is temporarily lowered from the receiving height position A by the first lifting / lowering driving cylinder 532, and the first horizontal driving cylinder 534 is driven. It moves horizontally to C and further rises from there, and becomes the state shown by the broken line in FIG.

In this state, the neck cavity mold 60 is lowered to the release position L indicated by the broken line in the figure, and the preform 1
Is released from the neck cavity mold 60 with the vicinity of the bottom inserted into the preform insertion portion 516, and the preform 1 falls as it is, and the support ring 2a of the preform 1 is placed on the holding member 508. The six preforms 1 that are placed and simultaneously molded are simultaneously held by the six holding members 508 in the upright state while maintaining the preform molding pitch, and the movement in the horizontal direction is restricted. Further, in a state where the preform 1 is held by the holding member 508, a cooling means for cooling the preform 1 by applying cooling air from below the preform 1 may be provided to promote cooling of the preform 1. is there.

When the preform 1 is received, the first lifting drive cylinder 532 is driven to lower the holding member 508 to the transport height position B. In this state, the first horizontal drive cylinder 534 is driven, Hold the holding member 508 in the holding position E
And stop.

During this movement, the pitch conversion drive cylinder 528 of the pitch conversion mechanism 522 is driven to widen the interval of the receiving member 520 from the preform molding pitch to the blow molding pitch to perform the pitch conversion.

When the preform 1 pitch-converted to the blow molding pitch is transferred to the holding position E, the six preforms 1 located at the receiving and holding position I of the reversing / transfer mechanism 504 stopped at the receiving and holding position I are moved. Neck holding mechanism 536
The holding member 50 is driven by the opening / closing drive mechanism 546.
The neck portion 2 of the preform 1 held at 8 is held in an upright state.

When the neck holding mechanism 536 holds the neck 2 of the preform 1, the second horizontal drive cylinder 55
8, the neck holding mechanism 536 is moved to the receiving section 304.
When the preform 1 moves to the side and reaches the standby position K, it is stopped by the halfway stop cylinder 559 and the preform 1 is put on standby until the receiving section 304 has six transfer members.

In this case, at the same time as the neck holding mechanism 536 starts moving, the holding member 508 moves in the opposite direction.
The half-stop cylinder 559 is moved toward the take-out section 16 against the driving force of the first horizontal drive cylinder 534, stops when the gate cutter 506 reaches the gate cut position D, and then moves to the take-out section 16. It will wait for the preform 1 to be conveyed.

In taking out the preform 1 from the holding member 508, when the neck holding mechanism 536 and the holding member 508 start moving, as shown in FIG.
The holding member 508 is opened by the opening / closing drive mechanism 546 to allow the preform 1 to slide and pass therethrough. After the passage, the preform 1 is closed again by the opening / closing drive mechanism 546 so that the preform 1 can be inserted and held.

Then, while the neck holding mechanism 536 holds the preform 1 and conveys it to the standby position H, the neck holding mechanism 536 is driven from the erect holding height position F to the inverted standby height by driving the reversing actuator 554. After rotating to the position G, the preform 1 in the upright state is inverted to the inverted state, and is positioned just before the receiving section 304 to be on standby.

In the receiving section 304, six empty transport members 330 are provided.
Are aligned, the driving force of the halfway stopping cylinder 559 is released, and the driving force of the second horizontal driving cylinder 558 moves the neck holding mechanism 536 to the delivery position J while maintaining the inverted standby height position G. Second lifting drive cylinder 5
According to 56, the neck part 2 of the preform 1
The preform forming station 10 is lowered to the delivery height position H placed on the preform forming station 10 by opening and closing the neck portion 2 of the preform 1 by the opening / closing drive mechanism 546.
As a result, the delivery of six preforms 1, which is the number of simultaneous moldings, is completed at the same time. During this delivery, the positioning member 543 engages with the transport member 330 to perform positioning, so that reliable delivery is performed.

After the completion of the delivery, the neck holding mechanism 536 is moved to the receiving standby position K by the second horizontal drive cylinder 558, and the neck holding mechanism 536 is moved to the original height position by the second lifting drive cylinder 556. While ascending, the reversing operation is performed by the reversing actuator 554, and the next preform 1 is received until the receiving / lowering mechanism 502 conveys it.

Next, FIGS. 35 to 38 show an injection stretch blow molding apparatus according to still another embodiment of the present invention.

The injection stretch blow molding apparatus according to this embodiment shows a case where the number of simultaneous moldings in the preform molding station 10 is three and the number of simultaneous moldings in the blow molding station 300 is one.

In the present embodiment, the three preforms 1 in the upright state, which have been simultaneously molded in the preform molding station 10, are transferred in the transfer station 600.
Receiving and descending mechanism 60 with preform molding pitch
After the two holding members 604 receive and hold the erect state at the same time, the pitch converting mechanism 606 converts the pitch from the preform forming pitch to the blow forming pitch while widening the interval.

In the reversing / delivery mechanism 608, three neck holding mechanisms 610 are set in advance at the blow molding pitch, and the neck holding mechanism 610 is converted to the blow molding pitch by the receiving / lowering mechanism 602. The three preforms 1 are received and held in an upright state from the holding member 604, and then inverted into an inverted state by an inversion driving device 538, and the three preforms 1 are transferred to the three transport members 330 of the receiving unit 304. They are handed over at the same time.

In the preform 1 of this embodiment, when the outer diameter of the support ring 2a of the neck portion 2 is substantially equal to or smaller than the outer diameter of the body portion, the support ring 2a is It is in a state that is difficult to use and hold.

Therefore, in the receiving and lowering mechanism 602, a holding member capable of inserting the bottom and the trunk of the preform 1 is used instead of the holding member 508 for supporting the lower surface of the support ring 2a in the embodiment of FIGS. A holding member 604 made of a heat insulating material such as a synthetic resin and having a preform insertion portion 612 is used to hold the preform 1 by contacting at least a part of the bottom and the body of the preform 1. When such a holding member 604 is used, it is also possible to flow cooling water into the holding member to promote cooling of the preform 1.

The holding member 604 is raised by the first lifting / lowering drive cylinder 532 and is brought into contact with the neck cavity mold 60. In addition, the neck cavity mold 60 is moved from the contact position M at the time of releasing the mold. The preform 1 is lowered to the mold release position L, and the contact position M is such that when the length of the preform 1 changes, for example, the length of the preform 1 decreases. In such a case, the position of the neck cavity mold 60 to be rotated and conveyed is reduced by the lower the injection cavity mold,
The height position of the bottom of the preform insertion portion 612 of the holding member 604 does not change. Accordingly, as the position of the neck cavity mold 60 is lowered, the mold release position L is also lowered, so that the moving amount of the neck cavity mold 60 can be absorbed by that amount. A guide member 614 for supporting the member 604 so as to be vertically movable.
And a spring 616 for urging the holding member 604 upward is attached to the guide member 614 so that a cushion is provided.

Further, the holding member 604 is used for the preform 1
Is received, it is lowered by the first raising / lowering drive cylinder 532 and moves to the transport height position B, and in this state, the pitch is converted to the blow molding pitch by the pitch conversion mechanism 606, while the first horizontal drive cylinder 534 converts the pitch to the blow molding pitch. , And moves to the reversing / delivery mechanism 608 side, and stops at the position O immediately below the erect holding height position F of the neck holding mechanism 610 in the reversing / delivery mechanism 608 located at the standby position K. From there, when the first lifting drive cylinder 532 moves up to the position of the neck holding mechanism 610, the neck holding mechanism 610 is closed by the opening / closing drive mechanism 546 to hold the neck 2 of the preform 1, and thereafter the holding member 604 is moved to the first position. The preform 1 is lowered by the vertical drive cylinder 532 and returned to the holding position D by the horizontal drive cylinder.
Is carried out to the take-out unit 16. Neck holding mechanism 610 holding preform 1
Is reversed by the reversing drive device 538 to the stand-by stand-by height position G as it is, and the preform 1 is set in the stand-by state and stands by. When the three transfer members 330 are aligned in the receiving section 304, the second The reversing / transfer mechanism 608 is moved to the transfer position J by the horizontal drive cylinder 558, and the neck holding mechanism 610 is lowered by the second lifting drive cylinder 556 to transfer the preform 1 to the transport member 330. .

Therefore, the receiving / lowering mechanism 602 is
Reciprocating between the preform receiving position C and the holding position E,
The reversing / transfer mechanism 608 includes a standby position K and a transfer position J
27, the intermediate stop cylinders 559 and 560 as in the embodiment of FIGS. 27 to 34 are not used.

Further, since the opening / closing drive mechanism 546 only needs to open and close the three neck holding mechanisms 610, the opening / closing drive cylinder 550 does not need to be provided as in the embodiment shown in FIGS. Only books are provided.

Further, the pitch conversion mechanism 606 is provided in FIG.
34, the pitch conversion is performed by the strokes of two pitch conversion drive cylinders 528.

Other structures and operations are the same as those of the embodiment shown in FIGS. 27 to 34, and the description thereof will be omitted.

It should be noted that the present invention is not limited to the above-described embodiments, and various modified embodiments are possible within the scope of the present invention.

In the above embodiment, the injection core mold 50 and the neck cavity mold 60 are conveyed by the turntable 30. However, for example, when the shape of the neck portion 2 is not undercut in the mold release direction, it is not always necessary. It is not necessary to use the neck cavity mold 60. In this case, the injection molding unit 1
After the release of the injection cavity mold 42 at 4, the preform 1 may be conveyed to the preform take-out section 16 only by the injection core mold 50. Since the preform 1 is contracted and deformed by cooling so as to be in close contact with the core pin 52 side of the injection core mold 50, the mold release of the injection cavity mold 42 can be performed smoothly, and even if the neck portion 2 does not have an undercut. The preform 1 can be transported by the injection core mold 50.

To release the injection core mold 50 from the preform 1 at the preform take-out section 16, for example, the following method can be adopted. That is, the core pin 52 of the injection core mold 50 only needs to have a function of introducing air for eject drive into the preform 1. in this case,
After the preform 1 is cooled by the injection core mold 50 in the preform take-out section 16, air is blown out by the core pin 52, and the preform 1 is compressed by the air pressure.
Can be dropped downward.

The holding member 604 of the preform 1 does not need to have the preform insertion portion 612 at the outer diameter of the body of the preform, but only needs to be in contact with a part of the body and the bottom. .

[Brief description of the drawings]

FIG. 1 is a plan view of an apparatus according to an embodiment of the present invention.

FIG. 2 is a front view of the embodiment device shown in FIG.

FIG. 3 is a left side view of the embodiment apparatus shown in FIG. 1;

FIG. 4 is an enlarged view of a main part of the device shown in FIG.

FIG. 5 is a bottom view of the turntable.

FIG. 6 is a schematic perspective view showing a release state of an injection core type in which a neck pressing plate is driven to descend.

FIG. 7 is a schematic cross-sectional view showing a mounting structure of an injection core type and a neck cavity type with respect to a rotary disk.

FIG. 8 is a schematic explanatory view of a preform take-out drive mechanism.

FIG. 9 is an enlarged sectional view of a portion A in FIG. 8;

FIG. 10 is a schematic explanatory view for explaining a release state of the injection core mold.

FIG. 11 is a schematic explanatory diagram for explaining a preform take-out drive.

FIG. 12 is a diagram illustrating the operation of a transfer station that receives a preform.

FIG. 13 is an operation explanatory view of a transfer station that transfers a preform to a blow molding station.

FIG. 14 is a plan view of a transfer station.

FIG. 15 is a side view of the transfer station.

FIG. 16 is a plan view of a transfer member of a second circulating transfer unit provided in the blow molding station.

FIG. 17 is a side view of the transport member shown in FIG.

FIG. 18 is a front view in which a part of the transport member is cut away.

FIG. 19 is a side view of the heating unit viewed from a preform conveyance direction.

FIG. 20 is a plan view schematically showing a rotary transport mechanism of a heating unit.

FIG. 21 is a plan view showing an apparatus according to another embodiment of the present invention in which the number of simultaneous moldings is changed.

FIG. 22 is an explanatory diagram of an operation of a transfer station that transfers a preform while performing pitch conversion.

FIG. 23 is a schematic sectional view showing a temperature control core arranged in a standby unit.

FIG. 24 is a schematic sectional view showing a temperature control pot arranged in a standby unit.

FIG. 25 is a schematic cross-sectional view showing a local temperature control member arranged in a standby unit.

26 is a schematic view of the flat container blow-molded after the temperature adjustment shown in FIG. 25.

FIG. 27 is a plan view showing a transfer station in an injection stretch blow molding apparatus according to another embodiment of the present invention.

28 is a plan view showing the open / closed state of the holding member opening / closing mechanism shown in FIG. 27.

FIG. 29 is a side view showing the preform of the transfer station shown in FIG. 27 in the course of being inverted;

FIG. 30 is a side view showing a state where the preform is completely inverted from the state of FIG. 29 and is delivered to the conveying member.

FIG. 31 is a front view showing the receiving and processing mechanism of FIG. 27;

FIG. 32 is a front view showing the reverse delivery mechanism of FIG. 27;

FIG. 33 is a side view of the injection stretch blow molding machine of the present embodiment.

FIG. 34 is a layout diagram of each part in the injection stretch blow molding apparatus of the present embodiment.

FIG. 35 is a plan view showing a transfer station in an injection stretch blow molding apparatus according to still another embodiment of the present invention.

FIG. 36 is a side view of the transfer station of FIG. 35.

FIG. 37 is a front view showing a receiving and processing mechanism in the transfer station of FIG. 35;

FIG. 38 is a front view showing the reverse transfer mechanism in the transfer station of FIG. 35;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Preform 2 Neck part 2a Support ring 4a Neck lower part 6 Bottle (container) 8 Machine stand 8a Drop opening 8b Shooter 10 Preform molding station 14 Injection molding part 16 Preform take-out part 30 1st circulation conveyance part (rotary disk) 42 Injection cavity mold 50 Injection core mold 52 Core pin 200 Transfer station 210, 502, 602 Receiving / lowering mechanism 230, 504, 608 Inverting / transferring mechanism 254 Pitch variable driving device 300 Blow molding station 302 Second circulating transport unit 304 Receiving unit 306 Heating Unit 308 Stand-by unit 310 Blow molding unit 312 Bottle take-out unit 320 Transport sprocket 322 Transport chain 330 Transport member 348 Rotating sprocket 352 Bar heater 356 Reflector 358 Rotating drive chain 3 6 Blow mold clamping mechanism 378 Blow cavity mold 500,600 Transfer station 508,604 Holding member 512 First horizontal drive 516 Preform insertion part 522,606 Pitch conversion mechanism 534 First horizontal drive cylinder 538 Inversion drive 542 First Horizontal drive unit 612 Preform insertion part

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shuichi Ogiwara 4586-3, Komoro-shi, Nagano Prefecture Nissei ASB Machine Co., Ltd. (56) References JP-A-56-60227 (JP, A) 1984-190834 (JP, A) JP-A-3-290225 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 49/00-49/80

Claims (4)

(57) [Claims] 1. A blow molding apparatus for blow-molding a preform into a container, comprising: a substantially rectangular transport path disposed on a horizontal plane; and supporting the preform or the container one by one on the transport path. A plurality of conveying members that are conveyed, one endless driving member that intermittently circulates and conveys the plurality of conveying members along the conveying path, and the preform supplied from outside the conveying path. ,
A first delivery unit for delivering to at least one of the plurality of transport members on the transport path, and a heater extending along a transport direction of the preform on a side of the transport path, wherein the at least one A heating unit that heats the preform supported by a conveying member, a blow molding unit that blow-molds the heated preform into a container, and a conveyance path between the heating unit and the blow molding unit, A standby unit that stops the preform by at least one intermittent stop operation, and waits for loading into the blow molding unit; a second delivery unit that delivers the blow molded container to the outside of the device; A cam follower provided on each of the plurality of transport members; and a cam follower disposed along the transport path, abutting on the cam follower of the transport member to transport and guide the transport member. Blow molding apparatus characterized by having a cam. 2. The device according to claim 1, wherein the first and second cams are disposed on both sides of the conveyance path.
A cam follower , wherein the cam follower is in contact with the first cam .
A cam follower and a second cam abutting on the second cam
A blow molding apparatus comprising a follower . 3. The blow molding apparatus according to claim 1, wherein the cam follower is a roller that rotates in contact with the cam . 4. The preheating apparatus according to claim 1, wherein a plurality of the heating units are arranged at intervals in a vertical direction on a side of the preform conveyance path, and each of the heating units is arranged in a conveyance direction of the preform. A plurality of first heaters extending along the preform, a reflector disposed opposite to the first heater with the preform conveyance path as a boundary, and the preform on both sides of the preform conveyance path. And a plurality of second heaters extending along the transport direction of the preform, wherein a height position of the second heater in a vertical direction is a position facing a blow molding target area near the neck portion of the preform. A blow molding apparatus characterized by being set.