JP2008207434A - Blow molding machine with air conditioning - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blow molding machine with air conditioning which can produce bottles with the continuous data of the bottles being the final shape stabilized even when an outside air temperature (temperature in a building) varies. <P>SOLUTION: High-temperature air sucked from a heating zone 1 is filtered by a primary filter 6 and a secondary filter 7, is subjected to heat exchange with a cooling water coil 8, is pressurized/sent by an air blower 10 to generate low temperature air, and part of the low temperature air is returned to a blow zone 2 through a return duct 13. A controller 23, based on the feedback signal of a temperature sensor 18, by driving a primary electromagnetic valve 81 and a secondary electromagnetic valve 91 or a motor 11, or the combination of these, controls the temperature of the low-temperature air returned to the blow zone 2 to be a set temperature. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an air-conditioning blow molding machine, and in particular, in biaxial stretch blow molding of a bottle based on a preform, even when the temperature of the environment in which it is placed fluctuates, the final shape of the bottle is measured. The present invention relates to an air-conditioned blow molding machine capable of producing a stable value.

A biaxial stretch blow molding method is widely used as a method of molding a plastic container such as a PET bottle. In this molding method, the body wall portion of a preform (semi-finished product) obtained by injection molding is heated by a heater, and then the heated preform is set in a temperature-controlled blow mold. This is a method in which a stretching rod is inserted into the interior, and the heating preform is stretched in the axial direction by the stretching rod, and at the same time, high-pressure air is injected from the side surface of the stretching rod to stretch in the radial direction.
By the way, in the above biaxial stretch blow molding, in order to prevent dew condensation on the injection mold and affect the molding of the preform, an injection molding station for molding the preform and a blow molding station for stretching and blowing the preform. Is separated by a separator sheet, and air from the injection molding station is sucked by an air conditioner, passed through a dehumidifying device, and air having a higher degree of dryness is blown into the injection molding station again to cause condensation in the injection mold. An air conditioner for an injection stretch blow molding machine configured to prevent this is known (see, for example, Patent Document 1).

JP 2000-202895 A

When the outside air temperature fluctuates, the temperature inside the building where the blow molding machine is placed fluctuates, and as a result, the atmospheric temperature inside the blow molding machine changes, and the preform heating temperature and blow mold temperature are set. Despite the temperature, the measured value of the bottle that is the final shape may change, and it may be difficult to stably produce the bottle.
However, in the air conditioner of the injection stretch blow molding machine, only the dehumidification of the injection molding station is performed, and the air conditioning control of the blow molding station where the stretch blow molding is performed is not performed, and the final shape is still due to the temperature fluctuation of the outside air. The problem of changing the bottle's measured value remains inherent.
Therefore, the present invention has been made in view of the problems of the prior art, and its purpose is to change the temperature of the environment in which it is placed in the biaxial stretch blow molding of a bottle based on a preform. Even if it is a case, it is providing the blow molding machine with an air conditioning which can stabilize and produce the measured value of the bottle which is the last shape.

In order to achieve the above object, the air-conditioning blow molding machine according to claim 1, further comprising: a heating zone for heating the preform; and a blow zone for stretching and blowing the preform biaxially; Is a blow molding machine in which a suction port and a blow-out port are respectively provided in the blow zone, and the air sucked from the heating zone is filtered into clean air, and the air is further fixed at the blow-out port. Adjust the temperature and flow rate so that the temperature / temperature range and a constant flow rate / flow rate range are obtained, and return part or all of the air from the blowout port to the blow zone again to the direction of the heating zone from the blow zone The atmospheric temperature of each of the heating zone and the blow zone is kept constant by continuously flowing into the heating zone.
In the above blow molding machine with air conditioning, a part or all of the clean air sucked and filtered from the heating zone is temperature-adjusted to a constant temperature and a constant flow rate at the outlet and then supplied again to the blow zone. By continuously flowing from the blow zone to the heating zone, the ambient temperatures of the blow zone and the heating zone are kept constant. In this way, cooling with air adjusted to a constant temperature and a constant flow rate, unlike indirect cooling such as water cooling, directly takes heat away from the object, resulting in a very high cooling efficiency. In addition, by rectifying the air flow from the blow zone to the heating zone, the influence of heat transfer by convection is minimized, and the ambient temperature of the blow zone and heating zone is kept constant. Will be able to. Moreover, since the air sucked from the heating zone is in a filtered and clean state, it can be discharged as it is into the building where the apparatus is placed. Therefore, when it is desired to keep the building at a positive pressure, it is possible to perform air conditioning management in the building by releasing a part of the air into the building. As a result, even if the temperature in the building fluctuates, the measured value of the final shape bottle is stabilized, and the total running cost for temperature management in the blow zone and heating zone and for maintaining positive pressure in the building is reduced. It will be reduced. In addition, by continuously flowing clean air from the blow zone to the heating zone, clean cleaning in the molding machine can be suitably achieved.

In the blow molding machine with air conditioning according to claim 2, the air sucked from the heating zone is opposed to the first cooling means having a flow rate adjusting function, and further while being pumped by the blowing means, the first cooling means It was configured to perform heat exchange.
In the above blow molding machine with air conditioning, when the heat exchange is performed between the high-temperature air sucked from the heating zone and the first cooling means, either the first cooling means or the blowing means is adopted. Alternatively, by operating both, it becomes possible to control the heat transfer amount of heat exchange, and as a result, it becomes possible to control the temperature of the air with high accuracy.

In the blow molding machine with air conditioning according to claim 3, the first cooling means is configured to exchange heat with a second cooling means having a separately provided flow rate adjusting function.
In the above blow molding machine with air conditioning, by adopting the above configuration, the heat taken by the first cooling means from the high-temperature air is preferably recovered by the second cooling means. As a result, heat exchange between the first cooling means and the high-temperature air is suitably performed, and the temperature of the air can be accurately controlled.

In the blow molding machine with air conditioning according to claim 4, the flow path downstream from the air blowing means is branched into a plurality of flow paths, and one branch flow path is configured to be returned to the blow zone. It was.
In the blow molding machine with air conditioning, the above-described configuration enables the reuse of clean air used for cooling the blow zone and the heating zone.

In the blow molding machine with air conditioning according to claim 5, one branch flow path returned to the blow zone is provided with a flow rate adjusting means.
With the above-described blow molding machine with air conditioning, it is possible to supply clean air having a constant temperature adjusted to a constant flow rate to the blow zone again by adopting the above configuration.

The blow molding machine with air conditioning according to claim 6, wherein at least one of the plurality of airflows flowing through the plurality of branch passages is discharged into a building in which the airflow is placed. It was decided that
In the above blow molding machine with air conditioning, by adopting the above configuration, temperature management or pressure management of the building in which the molding machine is installed can be performed together.

In the blow molding machine with air conditioning according to claim 7, the temperature control of the air returned from the air outlet is performed based on a feedback signal from a temperature sensor, the first cooling means and the second cooling means or the blower means or The control means for operating these combinations is configured to be performed.
In the air-conditioning blow molding machine, the above-described configuration enables accurate temperature control of the air.

According to the air-conditioning blow molding machine of the present invention, a part or all of clean air sucked and filtered from the heating zone and adjusted to a constant temperature and a constant flow rate at the outlet is returned to the blow zone. By continuously flowing from the heating zone to the heating zone, it is possible to keep the atmospheric temperatures of the blow zone and the heating zone constant. Thereby, even when the outside air temperature (the temperature in the building) fluctuates, the measured value of the final shape bottle is stabilized, and the bottle can be stably produced. Further, the air returned to the blow zone passes through the heating zone and becomes high-temperature air, is sucked from the suction port and performs heat exchange with the first cooling means, and is further pumped by the blowing means to become low-temperature air. It is configured to be reused. On the other hand, the remaining low-temperature air that is not reused is configured to be discharged into the building. Thereby, temperature management or pressure management of the building in which the molding machine is installed can be performed together. As a result, the total running cost for the temperature management of the blow zone and the heating zone and the temperature management of the building is reduced. Furthermore, the air flowing out from the blow zone outlet is clean, filtered air, and the clean air is continuously supplied from the blow zone to the heating zone. Preferably achieved.
In addition, the temperature of the air returned to the blow zone is adjusted with high accuracy because the operation of the first cooling means and the second cooling means, the operation of the air blowing means, or a combination of these is appropriately performed. Become.

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

FIG. 1 is a configuration explanatory view showing an air-conditioning blow molding machine 100 of the present invention.
This blow molding machine 100 with air conditioning is a heating zone 1 in which the preform P is preheated by a heater H, and the preheated preform P is set in a mold M and biaxially stretched blow molding is performed by a stretching rod R and high-pressure gas. Blow zone 2, housing 3 covering these zones, suction port 4 for sucking high-temperature air in heating zone 1, high-temperature duct 5 through which high-temperature air flowing in from suction port 4 flows, and coarseness for filtering the high-temperature air Primary filter 6, the same secondary filter 7, cooling water coil 8 as a first cooling means through which cooling water that takes heat away from high-temperature air flows, and a primary electromagnetic that adjusts the flow rate of the cooling water The cooling water coil 9 as the second cooling means, the secondary electromagnetic valve 91 for adjusting the flow rate of the cooling water, and the low temperature air are sent downstream. A blower 10 serving as a blowing means to be discharged, an electric motor 11 that drives the blower, a low-temperature duct 12 through which low-temperature air flows, a return duct 13 that leads to a blow zone, and a primary flow control that adjusts the flow rate of low-temperature air flowing into the blow zone A valve 14, a bleed duct 15 leading to the building, a secondary flow regulating valve 16 for adjusting the flow rate of the low-temperature air discharged into the building, an outlet 17 through which the low-temperature air flows out, and a low-temperature air flowing into the blow zone The in-side temperature sensor 18 for measuring the temperature of the air, the out-side temperature sensor 19 for measuring the temperature of the high-temperature air flowing out from the heating zone, and the measurement signals from the in-side temperature sensor 18 and the out-side temperature sensor 19 are taken in. The in-side temperature monitor 20 and the out-side temperature monitor 21 for displaying the temperature measurement value and inputting the set temperature by the user, and the return duct 13 flow. A flow meter 22 for measuring the quantity, and a control device 23 as a control means for controlling the number of revolutions of the primary solenoid valve 81, the secondary solenoid valve 91 and the electric motor 11 based on the deviation between the measured temperature value and the set temperature. It is comprised. For convenience of illustration, the chilled water coil 9 is drawn so as to face the high temperature air in parallel with the cooling water coil 8, but in actuality, heat exchange with the cooling water coil 8 is performed without facing the high temperature air. It is arranged.

  The heating zone 1 and the blow zone 2 are partitioned by a simple partition S that allows gas to flow in and out, and the air flow is configured to go from the blow zone 2 to the heating zone 1. Further, as will be described later, the air flowing out from the blowout port 17 is clean air whose temperature and flow rate are kept constant, and by continuously flowing the air, the air in the blow zone 2 and the heating zone 1 Each atmospheric temperature can be kept constant. Therefore, the problem that the measured value of the final shape bottle changes due to fluctuations in the outside air temperature, despite the fact that the heating temperature and the mold temperature are controlled to be constant, as found in conventional blow molding machines, It becomes difficult to get up.

  Further, the filtered, temperature-adjusted and flow-adjusted air is extracted and discharged into the building through the extraction duct 15, thereby contributing to maintaining positive pressure in the building.

  The air returned from the blower outlet 17 to the blow zone 2 is maintained at, for example, 20 ° C. and enjoys heat in the process of flowing from the blow zone 2 to the heating / heating zone 1, and is, for example, 50 to 55 ° C. in the vicinity of the suction port 4. The temperature has increased to. The heated hot air passes through the high temperature duct 5, passes through the primary filter 6 and the secondary filter 7, and is purified to a predetermined cleanliness level.

  The high temperature air purified to a predetermined cleanliness level gives its own heat to the cooling water coil 8 while being in contact with the cooling water coil 8, and at the same time receives cold heat from the cooling water coil 8 and is further pumped by the blower 10. The low-temperature air is lowered to about 20 ° C. and flows through the low-temperature duct 12. A part of the low-temperature air flowing through the low-temperature duct 12 returns to the blow zone 2 through the return duct 13, and the remaining low-temperature air is discharged into the building through the extraction duct 15. The temperature of the air returned to the blow zone 2 is measured by the in-side temperature sensor 18, and the measurement signal is transmitted to the in-side temperature monitor 20 and the control device 23. The in-side temperature monitor 20 that has received the measurement signal gives a temperature instruction. On the other hand, the control device 23 checks the deviation between the temperature instruction and the set temperature, and if a deviation occurs, drives the primary solenoid valve 81 to cool it. The flow rate of the cooling water flowing through the water coil 8 is adjusted to increase or decrease the heat transfer amount between the high-temperature air and the cooling water coil, and control is performed so that the indicated value of the in-side temperature sensor 18 is close to the set temperature. When the control device 23 drives the primary electromagnetic valve 81 to change the flow rate of the cooling water coil 8, in order to recover the excess heat of the cooling water coil 8 by the cooling water coil 9, The secondary electromagnetic valve 91 is driven in accordance with the driving to increase or decrease the flow rate of the cold water in the cold water coil 9.

  On the other hand, the flow rate of the low-temperature air returned to the blow zone 2 is adjusted by adjusting the opening degree of the primary flow control valve 14. The adjustment of the opening degree may be made manually based on the indicated value of the flow meter 22, and the measurement signal of the flow meter 22 is fed back to the control device 23 to open the primary flow regulating valve 14 by the control device 23. You may comprise so that degree adjustment may be performed automatically. Further, the flow rate of the remaining low-temperature air is adjusted by adjusting the opening degree of the secondary flow control valve 16 in the same manner.

  Further, the ambient temperature of the heating zone 1 is measured by the out-side temperature sensor 19, and the measurement signal is transmitted to the out-side temperature monitor 21 and the control device 23. The out-side temperature monitor 21 that has received the measurement signal gives a temperature instruction. On the other hand, the control device 23 checks the deviation between the temperature instruction and the set temperature, and if a deviation occurs, for example, operates the inverter INV of the motor 11. The air flow rate of the blower 10 is adjusted to increase or decrease the flow rate of the low-temperature air, and the indicated value of the out-side temperature sensor 19 is controlled to be close to the set temperature.

  In the present embodiment, the cold water coil 9 exchanges heat with the cooling water coil 8 without facing the high temperature air, but is not limited thereto, and is opposed to the high temperature air with the high temperature air. You may comprise so that heat exchange may be performed. In this case, the heat of the high temperature air is suitably recovered by both the cooling water coil 8 and the cooling water coil 9.

As described above, according to the blow molding machine 100 with the air conditioner, a part or all of clean air sucked and filtered from the heating zone 1 and adjusted to a constant temperature and a constant flow rate at the blowout port 17 is returned to the blow zone 2 again. By returning and continuously flowing from the blow zone 2 to the heating zone 1, it becomes possible to keep the atmospheric temperatures of the blow zone 2 and the heating zone 1 constant. Thereby, even when the outside air temperature fluctuates, the measured value of the final shape bottle is stabilized, and stable production of the bottle becomes possible. Further, the air returned to the blow zone 2 passes through the heating zone 1 and becomes high-temperature air, is sucked from the suction port 4 and exchanges heat with the cooling water coil 8, and is further pumped by the blower 10 to be fed with the low-temperature air. It is configured to be reused. On the other hand, the remaining low-temperature air that is not reused is configured to be discharged into the building. Thereby, temperature management or pressure management of the building where the molding machine 100 is installed can be performed together. As a result, the total running cost for the temperature management of the blow zone 2 and the heating zone 1 and the temperature management of the building is reduced. Furthermore, since the air flowing out from the blowout port 17 of the blow zone 2 is filtered clean air, and the clean air is continuously supplied from the blow zone 2 to the heating zone 1, the blow zone 2 and the heating zone No. 1 clean and clean is preferably achieved.
The temperature of the air returned to the blow zone 2 is adjusted by adjusting the flow rate of the cooling water in the cooling water coil 8 and the flow rate of the cooling water in the cooling water coil 9, adjusting the air volume of the blower 10, or a combination thereof. Therefore, it is performed with high accuracy.

  As another embodiment, the air conditioners from the inlet 4 to the outlet 17 to the controller 23 are arranged separately and independently with respect to the heating zone 1 and the blow zone 2 so as to keep each ambient temperature constant. It may be configured.

  The air-conditioning blow molding machine 100 of the present invention is a process performed in a housing (protective cover) including biaxial stretch blow molding of a plastic bottle or the like, and a process that requires accurate temperature control in the housing. The present invention can be preferably applied.

It is composition explanatory drawing which shows the blow molding machine with an air conditioning of this invention.

Explanation of symbols

1 Heating Zone 2 Blow Zone 3 Housing 4 Suction Port 5 High Temperature Duct 6 Primary Filter 7 Secondary Filter 8 Cooling Water Coil 9 Cold Water Coil 10 Blower 11 Electric Motor 12 Low Temperature Duct 13 Return Duct 14 Primary Flow Control Valve 15 Extraction Duct 16 2 Next flow control valve 17 Outlet 18 Inner side temperature sensor 19 Outer side temperature sensor 20 Inner side temperature monitor 21 Out side temperature monitor 22 Flow meter 23 Control device 100 Blow molding machine with air conditioning

Claims (7)

  Blow molding comprising a heating zone for heating a preform and a blow zone for stretching and blowing the preform biaxially, and further comprising a suction port in the heating zone and a blow-out port in the blow zone. The air sucked from the heating zone is filtered to obtain clean air, and the air is further adjusted in temperature and flow rate so as to have a constant temperature / temperature range and a constant flow rate / flow rate range at the outlet. Then, a part or all of the air is returned again from the outlet to the blow zone and continuously flows in the direction from the blow zone to the heating zone so that the ambient temperature of the heating zone and the blow zone is kept constant. A blow molding machine with air conditioning characterized by being held in the air.   The air sucked from the heating zone is opposed to a first cooling means having a flow rate adjusting function, and is configured to exchange heat with the first cooling means while being pumped by a blowing means. The blow molding machine with air conditioning described in 1.   The blow molding machine with air conditioning according to claim 2, wherein the first cooling means is configured to exchange heat with a second cooling means having a flow rate adjusting function provided separately.   4. The air-conditioned blow according to claim 1, wherein a flow path downstream from the blowing unit is branched into a plurality of flow paths, and one branched flow path is returned to the blow zone. Molding machine.   The blow molding machine with air conditioning according to claim 4, wherein the one branch flow path returned to the blow zone includes a flow rate adjusting means.   The blow molding with air conditioning according to claim 4 or 5, wherein at least one of the plurality of air flows flowing through the plurality of branch flow paths is discharged into a building in which the air flow is placed. Machine.   Control of the temperature of the air returned from the air outlet is performed by control means for operating the first cooling means, the second cooling means, the air blowing means, or a combination thereof based on a feedback signal from a temperature sensor. The blow molding machine with air conditioning according to any one of claims 1 to 6, wherein the blow molding machine is configured with air conditioning.

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