Control method of manufacturing apparatus, manufacturing method of resin container, control device of manufacturing apparatus, and resin container manufacturing apparatus having the same

Abstract

Provided is a control method of a manufacturing apparatus for manufacturing a resin container by blow molding a preform, the method including: a step (S100) for acquiring a target value of a temperature inside a heating device for heating the preform to a temperature suitable for blow molding; a step (S100) for acquiring an actual measurement value of the temperature inside the heating device, the temperature having been detected by a sensor provided inside the heating device; a step (S120) for calculating a temperature difference between the target value and the actual measurement value; and a step (S130) for adjusting a heating performance and a cooling performance of the heating device based on the temperature difference.

Description

Technical Field

[0001] This invention relates to a control method for a manufacturing apparatus, a method for manufacturing a resin container, a control device for the manufacturing apparatus, and a manufacturing apparatus for a resin container having a control device. Background Technology

[0002] Patent document 1 discloses a blow molding apparatus for a resin container, which includes at least a blow molding section, a heating unit, and a conveying path for conveying a preform heated in the heating unit to the blow molding section.

[0003] Reference List

[0004] Patent documents

[0005] Patent Document 1: WO2020 / 066749 Summary of the Invention

[0006] Technical issues

[0007] For blow molding equipment configured to manufacture beverage containers and the like in mass production, extremely high productivity and efficiency are required. Such equipment includes a heating device configured to raise the temperature of the conveyed preform to an optimal blow molding temperature. The heating device is configured to heat the preform using near-infrared (light) radiant heat from a near-infrared heater and convective heat from the high-temperature air (atmosphere) within the heating device. If the heater output and ambient temperature are not properly regulated, the preform cannot be heated to the optimal temperature. Preforms not at the optimal blow molding temperature are discarded because they cannot be blow molded into good containers. Furthermore, although the temperature of the air inside the heating device is raised and regulated to the predetermined temperature using heaters and blowers, this process takes a relatively long time.

[0008] Here, when the blow molding machine is stopped for any reason, the power supply to the heating device is usually also stopped. That is, since the air inside the heating device becomes outside the optimal temperature even during a temporary stop, its temperature must be raised and regulated except at the point before operation resumes. There is a need for heating methods and devices capable of raising the temperature in the early stages, which can reduce the amount of preforms that will be discarded unnecessarily.

[0009] The present invention provides a control method for a manufacturing apparatus, a method for manufacturing a resin container, a control device for the manufacturing apparatus, and a control device for a resin container having the ability to raise the temperature of the air or preform inside the heating device to an optimal temperature in an early stage.

[0010] Solution

[0011] A control method for a manufacturing apparatus according to one aspect of the invention is a control method for a manufacturing apparatus configured to manufacture resin containers by blow molding preforms. The control method includes: a step of acquiring a target value of a temperature inside a heating device configured to heat the preform to an optimal temperature for blow molding; a step of acquiring an actual measured value of the temperature inside the heating device, detected by a sensor arranged inside the heating device; a step of calculating the temperature difference between the target value and the actual measured value; and a step of adjusting the heating and cooling performance of the heating device based on the temperature difference.

[0012] A method for manufacturing a resin container according to one aspect of the present invention includes an injection molding step of injection molding a bottomed resin preform and a blow molding step of manufacturing a resin container by blow molding the preform in the injection molding step, wherein the above-described control method of the manufacturing apparatus is performed so as to heat the preform formed in the injection molding step to an optimal temperature for blow molding.

[0013] According to one aspect of the invention, a control device for a manufacturing apparatus is a control device for a manufacturing apparatus configured to manufacture resin containers by blow molding preforms. The control device includes: a target value acquisition unit configured to acquire a target value of temperature within a heating device configured to heat the preform to an optimal temperature for blow molding; an actual measurement value acquisition unit configured to acquire an actual measurement value of the temperature within the heating device detected by a sensor arranged within the heating device; a calculation unit configured to calculate the temperature difference between the target value and the actual measurement value; and an adjustment unit configured to adjust the heating and cooling performance of the heating device based on the temperature difference.

[0014] According to one aspect of the present invention, a resin container manufacturing apparatus comprises: an injection molding section configured to injection mold a bottomed resin preform; a heating unit including a heating device configured to heat the preform to a preform temperature for blow molding; a blow molding section configured to manufacture a resin container by means of a preform heated in the blow molding heating unit; and a control device for the above-described manufacturing apparatus.

[0015] Beneficial effects of the present invention

[0016] According to the present invention, it is possible to provide a control method for a manufacturing apparatus, a method for manufacturing a resin container, a control device for a manufacturing apparatus, and a control device for a resin container having the ability to raise the temperature of air or preforms in a heating device to an optimal temperature in an early stage. Attached Figure Description

[0017] Figure 1 This is a schematic top view of a blow molding apparatus.

[0018] Figure 2 This is a schematic side view of a blow molding apparatus.

[0019] Figure 3 This is a top view of the conveyor section.

[0020] Figure 4 This is a block diagram of the control device.

[0021] Figure 5 An example is shown of an element of the display unit that displays the operating status of the blow molding apparatus.

[0022] Figure 6 An example is shown where the display unit displays the target value and the actual measured value of the temperature inside the heating device.

[0023] Figure 7 Another example is shown where the display unit shows the target value and the actual measured value of the temperature inside the heating device.

[0024] Figure 8 An example of the flow of the control method is shown.

[0025] Figure 9 The inner side of the heater box is shown, which is provided for a heating unit of a particular aspect.

[0026] Figure 10 The external aspect of the heater housing is shown, which is configured for a specific heating unit.

[0027] Figure 11 The diagram shows the conduit used to introduce cooling air into the heater housing. Detailed Implementation

[0028] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that, for ease of description, the dimensions of each component shown in the drawings may differ from the dimensions of each actual component.

[0029] Additionally, in the description of this embodiment, for ease of description, "left-right direction," "front-back direction," and "up-down direction" are mentioned as appropriate. These directions are for... Figure 1 and Figure 2 The blow molding apparatus shown is arranged in relative directions. Here, "vertical direction" includes both "up" and "down". "Forward and backward direction" includes both "forward" and "backward". "Left and right direction" includes both "left" and "right".

[0030] Figure 1This is a schematic top view showing the general aspects of a blow molding apparatus 1 for a resin container (an example of a resin container manufacturing apparatus) according to an embodiment. Figure 2 This is a schematic side view showing an overall aspect of the blow molding apparatus 1 according to an embodiment. The blow molding apparatus 1 includes: an injection molding section 100 configured to mold a resin preform 10; a blow molding section 500 configured to mold a container 20 by blow molding the preform 10; and a conveying section 300 configured to convey the preform 10 formed in the injection molding section 100 to the blow molding section 500. Figure 1 The blow molding device 1 is a hot preform type (1.5 grade) blow molding device, in which N preforms 10 that are simultaneously injection molded are blow molded n times, with M preforms each time.

[0031] The blow molding apparatus 1 includes: a take-out device 150 configured to take out a preform 10 from the injection molding section 100; a preform conveying device 220 configured to convey the preform 10 from the take-out device 150; and a first flipping section (post-cooling component) 200 configured to convey the preform 10 from the preform conveying device 220 to a conveying section 300. Figure 2 Furthermore, the blow molding apparatus 1 includes a second tilting section 400, which is configured to convey the preform 10 from the conveying section 300 to the blow molding section 500. Figure 2 Furthermore, the blow molding apparatus 1 includes a control device 600 and an input / output device 700. Figure 1 and Figure 2 ).

[0032] The injection molding unit 100 is configured to injection mold N preforms 10 in n rows (n is an integer of 2 or greater) parallel to the left-right direction, M at a time (M = N / n: M is a natural number). The injection molding unit 100 includes: an injection device 110 configured to inject resin; an injection core mold 120; an injection neck mold (not shown); an injection cavity mold 130; and a mold closing mechanism configured to drive the mold closing along four linkages 140. Figure 1 As shown, the maximum number N of preforms that can be simultaneously injection molded in the injection molding section 100 can be, for example, 24 (3 rows × 8 preforms). When the diameter of the preform is large, 4 preforms can be arranged in each row, and therefore, the total number N for the 3 rows is 12.

[0033] The removal device 150 is configured to remove N preforms 10 formed in the injection molding section 100. The removal device 150 is configured to be able to move N (e.g., 3 rows × 8) holding members 152 (e.g., cans) horizontally at a receiving position P1 below the injection core mold 120 and at a delivery position P2 outside the space surrounded by the tie rod 140.

[0034] The precast component conveying device 220 is configured to hold the precast component in a position Figure 2 N preforms 10 from the three rows of holding members 152 of the take-up device 150 at the delivery position P2 shown are conveyed to the first flipping section 200. The preform conveying device 220 includes a preform holder 222, a first conveying mechanism 224, and a second conveying mechanism 226. The first conveying mechanism 224 is configured to move the preform holder 222 up and down in the vertical direction, and the second conveying mechanism 226 is configured to move the preform holder 222 and the first conveying mechanism 224 horizontally in the front-back direction. For example, a cylinder or servo motor is used as the drive source for the first conveying mechanism 224 and the second conveying mechanism 226.

[0035] The first flipping section 200 is a component for post-cooling (additional cooling) of the preform 10, and is configured to flip the preform 10 from its upright state formed in the injection molding section 100 to a flipped state with the neck facing down, and deliver it to the conveying section 300. The first flipping section 200 includes a first flipping member 210. The first flipping member 210 has N first flipping tanks 212 and N second flipping tanks 214 disposed facing the first flipping tanks 212. The first flipping tanks 212 and the second flipping tanks 214 (the first flipping member 210) are configured to intermittently flip 180° about an axis. The first flipping member 210 is configured to be able to move up and down by a ball screw or the like driven by a drive source 216 (e.g., a servo motor).

[0036] The conveying unit 300 is configured to convey the preform 10 from the injection molding unit 100 to the blow molding unit 500 via the first flipping unit 200. Figure 3 This is a top view showing one embodiment of the conveying unit 300. The conveying unit 300 includes a plurality of first conveying members 310 configured to support the preform 10. M first conveying members 310 are connected by connecting members to form a set of first conveying members 310. The connecting members of the set of first conveying members 310 are configured to be driven by a first conveying drive unit 320 and a second conveying drive unit 330, described later. Figure 3In the diagram, the position of the foremost first conveyor member 310 (or prefabricated component 10) in a group of first conveyor members 310 is marked with a double circle to distinguish it from the other seven. Each of the first conveyor members 310 is configured to rotate about an axis. Note that it is also possible to use a configuration where the first conveyor members 310 are not connected. In this case, each first conveyor member 310 is provided with a component that engages with a continuous / intermittent drive component such as a sprocket.

[0037] The conveying unit 300 has a circular conveying path formed by tracks or the like, and is configured to periodically convey the first conveying member 310 along the conveying path. The conveying unit 300 includes sprockets 330a, 330b, 330c, and 330d, configured as a first conveying drive unit 320 to continuously drive the first conveying member 310, and sprockets 330a, 330b, and 330c, configured as a second conveying drive unit 330 to intermittently drive the first conveying member 310. In the first conveying drive unit 320, sprockets 320d, 320c, 320b, and 320a are arranged from the upstream side in a corresponding order. In the second conveying drive unit 330, sprockets 330a, 330b, and 330c are arranged from the upstream side in a corresponding order.

[0038] The area where the first conveying member 310 is continuously driven by the first conveying drive unit 320 is the continuous conveying area T1, and the area where the first conveying member 310 is intermittently driven by the second conveying drive unit 330 is the intermittent conveying area T2. The continuous conveying area T1 is located upstream of the conveying section 300, further than the intermittent conveying area T2. A heating unit 360 configured to heat the preform 10 to a temperature suitable for blow molding is provided in the continuous conveying area T1. The heating unit 360 is arranged in the continuous conveying area T1 along a path spanning sprockets 320c, sprockets 320b, and sprockets 320a. The heating unit 360 can be configured by arranging heating devices in a manner that surrounds the conveying section 300 in the continuous conveying area T1. These heating devices include heaters, such as quartz heaters and flat reflectors, arranged at intervals in the conveying direction and in multiple stages in the height direction (vertical direction). Inside the heating unit 360, a blower is configured to blow air from the back side of the heaters.

[0039] Additionally, the conveying section 300 includes a parallel drive device 370, which is located below the first tilting section 200 and configured to drive in parallel a group (n+1) or more (e.g., four (four rows)) of first conveying members 310. Figure 2The parallel drive unit 370 is configured by attaching the ends of a plurality of conveying tracks to two chains 374 spanning two sprockets 372a and 372b at their ends in the front-rear direction. When one of the sprockets 372a and 372b rotates one step, the conveying track moves one step. The leading row of a set of first conveying members 310 arranged in the parallel drive unit 370 is configured to be pushed to the left by a transfer device (not shown), including, for example, a cylinder. Thus, a set of first conveying members 310 on which the preform 10 is placed is continuously conveyed by sequentially engaging with the continuously driven sprocket 320d. The parallel drive unit 370 is configured to convey another set of first conveying members 310 one step forward after conveying one set of first conveying members 310 to the left. The last row of the parallel drive unit 370 is configured to receive a set of first conveying members 310 on which the preform 10 conveyed from the sprocket 330c is not placed.

[0040] The foremost first conveyor member 310 of the first group of first conveyor members 310 is moved out by the removal device and engaged with the upstream sprocket 320d, such that a continuous conveying force is applied from the sprocket 320d to the group of first conveyor members 310. When a driving force is applied to each group of first conveyor members 310 engaged with the four continuously driven sprockets 320a, 320b, 320c and 320d present in the continuous conveying area T1, another group of first conveyor members 310 not engaged with the sprocket continuously driven on its upstream side is pushed, and thus, multiple groups of first conveyor members 310 are continuously conveyed along the conveying direction of the continuous conveying area T1.

[0041] The second turning part 400 is arranged between sprockets 330a and sprockets 330b in the intermittent conveying area T2 of the conveying part 300. Figure 1 and Figure 2 The second flipping section 400 includes a second flipping member (not shown) configured to flip the preform 10, which has been conveyed to the position of the second flipping section 400 by the conveying section 300, from a flipped state to an upright state. A set of first conveying members 310 is intermittently driven by a second conveying drive unit 330, such that the set of first conveying members 310 stops at the position of the second flipping section 400 for a predetermined time.

[0042] The blow molding section 500 is configured to form a resin container 20 by stretching M preforms 10 with blow molding air. The blow molding section 500 includes: a blow molding cavity mold, which is a split mold that can be opened and closed in the left-right direction and defines the shape of the main body of the container 20; a liftable bottom mold that defines the bottom of the container 20; and a second conveying member 530 for conveying the preforms 10 and the container 20 in the front-back direction. In addition to these, the blow molding section 500 may include a stretching rod, a blow molding core mold, a neck mold, etc. With the stretching rod, the preforms are biaxially stretched to form the resin container 20 by using blow molding air and driving the vertical axis of the stretching rod.

[0043] The second conveying member 530 is a chuck member configured to clamp the necks of M preforms 10 or containers 20 and intermittently convey the preforms. The second conveying member 530 includes a retaining arm configured to clamp the necks of the preforms 10 or containers 20. The second conveying member 530 integrally includes an infeed unit 534 and an outfeed unit 536, and is configured to reciprocate in a front-rear direction. The reciprocating drive is implemented, for example, by a servo motor. The reciprocating drive causes the infeed unit 534 to reciprocate between a preform receiving position B1 and a blow molding position B2, and causes the outfeed unit 536 to reciprocate between a blow molding position B2 and a removal position B3. The retaining arm is configured to be integrally driven, for example, by the driving force of an air cylinder, to open and close in a left-right direction. Furthermore, when moving from the preform receiving position B1 to the blow molding position B2, the row pitch (distance between the corresponding preforms) of the corresponding holding arm of the loading unit 534 is configured to change from a narrow pitch at the preform receiving position B1 to a wide pitch at the blow molding position B2.

[0044] The control device 600 is a device configured to control the blow molding device 1. Figure 4 This is a block diagram illustrating the configuration of the control device 600 according to this embodiment. The control device 600 includes a processor 610, a main memory 630, a memory 650, and an interface 670. A program for controlling the blow molding apparatus 1 is stored in the memory 650. Examples of the memory 650 include a hard disk drive (HDD), a solid-state drive (SSD), non-volatile memory, etc. The processor 610 is configured to read the program from the memory 650, expand it in the main memory 630, and execute processing according to the program. In addition, the processor 610 is configured to secure storage areas in the main memory 630 or the memory 650 according to the program. The processor 610 is configured to function as a target value acquisition unit 612, an actual measurement value acquisition unit 614, a calculation unit 616, an adjustment unit 618, and a cycle time control unit 620 by executing the program.

[0045] The target value acquisition unit 612 is configured to acquire a target value of the temperature within the heating device of the heating unit 360, which is configured to heat the preform 10 to an optimal temperature for blow molding. The target value may be an input value from the input unit 720 of the input / output device 700 described later, or it may be a target value pre-stored in the memory 650.

[0046] The actual measurement value acquisition unit 614 is configured to acquire the actual measured value of the temperature inside the heating device detected by a sensor arranged inside the heating device of the heating unit 360. The calculation unit 616 is configured to calculate the temperature difference between the target value acquired by the target value acquisition unit 612 and the actual measured value acquired by the actual measurement value acquisition unit 614.

[0047] The regulating unit 618 is configured to adjust the heating and cooling performance of the heating device based on the temperature difference calculated by the calculation unit 616. For example, heating performance refers to the output of the heater, and cooling performance refers to the output of the blower. When the heating device of the heating unit 360 is arranged in multiple separate predetermined areas, the regulating unit 618 can be configured as a segmented regulating unit to adjust the heating and cooling performance of each predetermined area. For example, the area between sprockets 320c and 320b can be designated as area 1, the area between sprockets 320b and 320a can be divided into three equal parts, and the two upstream parts of the divided portions can be designated as area 2, and the remaining portion can be designated as area 3 (see below). Figure 5 Temperature sensors can be installed in each predetermined zone. However, the heating and cooling performance of each predetermined zone can be adjusted based on actual temperature measurements of that zone.

[0048] The cycle time control unit 620 is configured to control the injection molding section 100 of the blow molding apparatus 1 to extend the injection molding cycle time of the preform 10 in the injection molding section 100 until the temperature in the heating unit reaches the target value.

[0049] The input / output device 700 includes a display unit 710 and an input unit 720. The input unit 720 includes an input device, such as buttons or a keyboard, for inputting control commands to the blow molding apparatus 1. The display unit 710 includes a display device, such as a monitor, for outputting operational information about the blow molding apparatus 1.

[0050] Figure 5 An example is shown of aspects of the display unit 710 that displays the operating status of the blow molding apparatus 1. Specifically, Figure 5 This is an example of a screen used to jointly confirm and set information about the ambient temperature within the heating device and the heating conditions of the preform 10.

[0051] exist Figure 5 In the heating device, the actual measured air temperature (ambient temperature) in each predetermined zone (zone 1, zone 2, zone 3) is displayed in "Heater Box Temperature". The actual measured temperature (surface temperature) of the preform 10 is displayed in "Preform Temperature". Specifically, the actual measured temperature before heating is displayed in "Before Reheating", and the actual measured temperature after heating is displayed in "After Reheating", with the maximum and minimum values ​​displayed in "Maximum" and "Minimum" respectively. The temperature setting for enabling blow molding of the preform 10 is displayed in "Blow Molding", with the minimum temperature setting displayed in "Low" and the maximum temperature setting displayed in "High". The values ​​indicated in "Blow Molding" can be set by operator input.

[0052] The output settings of multiple blowers used to cycle the external air inside the heating device are displayed in "Blowers". The output settings of the blowers used to cool the preform (particularly the neck) are displayed in "Preform Cooling", and the output settings of the blowers used to regulate the temperature of the air (atmosphere) inside the heating device are displayed in "Zone 1" and "Zones 2, 3" respectively. The values ​​indicated in "Blowers" can be set by operator input. Note that when performing the following... Figure 6 When adjusting the temperature as shown, Figure 5 The setting for the "blower" shown is disabled. Furthermore, the set value for the flow rate of the refrigerant supplied to prevent overheating of the heating device is displayed in the range to the right of "flow" for "cooler water," and its actual measured value is displayed in the range to the left of "flow." The set value for the refrigerant flow rate displayed in the range to the right of "flow" can be set by operator input. Additionally, the actual measured value of the refrigerant temperature is displayed in "temperature."

[0053] Figure 6 An example is shown of the display unit 710 displaying the target value and the actual measured value of the temperature inside the heating device. Specifically, Figure 6 This is an example of a screen used to raise and regulate the ambient temperature inside a heating device to a target value in an early stage. Figure 6 The diagram shows that the difference between the target value and the actual measured value of the ambient temperature for automatic temperature rise control of the heating device is set, and the outputs of the heater and blower are set to correspond to this difference.

[0054] exist Figure 6 In the display, the actual measured value of the ambient temperature of a predetermined area is shown in the "Heater Box Temperature". Figure 6In the text, a target value for the ambient temperature of a predetermined area is displayed in "Target". At least one set value is used to determine the temperature difference between the target value and the actual measured ambient temperature that triggers automatic temperature rise control (automatic temperature regulation control). Figure 6 The four values ​​in the table are displayed in "Temperature Difference". The temperature difference setting can be set by the operator.

[0055] In addition, Figure 6 In the automatic temperature rise control, the adjustment degree of heating and cooling performance corresponding to the temperature difference between the target value and the actual measured value, i.e., the set values ​​of the heater and blower outputs, are displayed in "Precast Heater" and "Blower," respectively. The set values ​​of the heater and blower outputs can be set by operator input. Multiple temperature differences are set when the adjustment degree of heating and cooling performance is changed for each temperature difference, and the output values ​​of the heater and blower are set for each temperature difference. The output values ​​of the heater and blower in the automatic temperature rise control can be set for each of the predetermined areas with different positions within the heating device (for the heater, at least three positions of "Area 1," "Area 2," and "Area 3," and for the blower, at least three positions of "Precast Cooling," "Area 1," and "Areas 2, 3"). Additionally, in... Figure 6 In the injection molding section 100, the extent of the extension of the injection molding cycle time of the preform 10 is displayed in the "cycle".

[0056] according to Figure 6 The adjustment shown is, for example, when the actual measured value is 9°C (-9°C) below the target value, the heater output increases by 10% from the setting value for molding (the output value of the heater used for actual molding, not shown), and the blower output decreases by 20% from the setting value for molding (the output value of the blower used for actual molding, not shown). Next, when the temperature rises, and therefore the actual measured value becomes 4°C (-4°C) below the target value, for example, the heater output increases by 5% from the setting value for molding, and the blower output decreases by 10% from the setting value for molding. This control is repeated until the actual measured value approaches the target value. In this way, because the outputs of the heater and blower are gradually and automatically adjusted according to the actual measured value, the ambient temperature can approach the target value earlier and automatically without increasing the operator's workload. Note that the set values ​​for the heater and blower can be increases or decreases relative to the setting value for molding or the actual output value. Figure 6 In this context, the settings for the heater and blower are set with increment / decrement rates relative to the settings used for molding.

[0057] Note that the settings for the output of the heaters and the blowers in each predetermined zone may be inconsistent and may differ within each zone. For example, the invention is not limited to changing the output of each of "Zone 1", "Zone 2", and "Zone 3", and the output of a portion of the heaters arranged in a multi-level shape in the vertical direction (vertical direction) (e.g., the lowest-level heater) can be configured to be set independently of the outputs of other heaters (e.g., a separate display / setting screen can be provided for the "prefabricated heater" of the lowest-level heater). Thus, the output of the lowest-level heater, which is closest to the reflector, can be independently controlled and used for the early temperature rise of the reflector, and the rate of temperature rise of the ambient temperature can be increased by dissipating heat to the reflector.

[0058] Furthermore, the output settings of the heater and blower in each predetermined zone can be continuously changed via feedback control based on actual measured values. Specifically, the output is preferably controlled by a decay curve that changes steplessly in response to actual measured values. Moreover, since the difference between the actual measured value and the target value of the ambient temperature is large at the beginning, the heater and blower can output uniformly based on the set values ​​(heater output: large, blower output: small), and during the transition period when the actual measured value approaches the target value and at the end, the output of the heater and blower can be gradually or continuously changed via feedback control based on the actual measured values. Specifically, the output is preferably controlled by a decay curve that changes steplessly based on actual measured values. The temperature during switching control can be set separately on the screen or incorporated into the program. This allows the temperature of the air (atmosphere) inside the heating device to be raised earlier and appropriately. Note that after the ambient temperature reaches the target value, the output of the heater or blower is adjusted based on separately set predetermined heating conditions during molding (heating conditions during actual blow molding of the preform).

[0059] Figure 7 Another example is shown where the display unit 710 displays the target value and the actual measured value of the temperature inside the heating device. Figure 7 In this system, the actual measured value of the ambient temperature in a predetermined area is displayed in the "Heater Box Temperature" field. Figure 7 In the display, the target value of the ambient temperature in a predetermined area is shown in "Target". The set value of the temperature difference between the target value and the actual measured value of the ambient temperature used to switch automatic temperature rise control (automatic temperature regulation control) is shown in "Control Start Temperature Difference". The set values ​​for the target values ​​of ambient temperature and temperature difference can be set by operator input.

[0060] exist Figure 7In the initial state, the outputs of the heater and blower are displayed in "Heater Power Setting at Control Start" and "Blower Setting at Control Start," respectively. The outputs of the heater and blower in the initial state can be set by operator input. Figure 7 In the example shown, starting from the point when the temperature difference between the target value and the actual measured value of the ambient temperature becomes equal to or less than the setpoint used to switch the automatic temperature rise control, the output of the heater and blower is controlled based on a decay curve (such as the nth-order curve) that changes steplessly according to the actual measured value. The decay curve is calculated based on a predetermined exponential function incorporated into the program. During the period when the temperature difference between the target value and the actual measured value of the ambient temperature exceeds the setpoint used to switch the automatic temperature rise control, the heater and blower regulate the ambient temperature with their initial output (constant output). The control transition sequence (sequence) of the predetermined exponential function used to calculate the decay curve in the control of the heater and blower output is displayed in the "Transition Sequence". The setpoint for the control transition sequence can be set by the operator's input. In addition, for the first stage (lowest stage heater) of heaters arranged in a multi-level shape in the vertical direction (up and down direction), the output of the heater in the initial state is displayed in the "First Stage" column, and for the second stage and above (heaters above the first stage), the output of the heater in the initial state is displayed in the "Second Stage and Above" column. Note that in the columns for "Heater Power Setting at Control Start" and "Blower Setting at Control Start," starting from the left in the attached diagram, the heater corresponds to the three positions of "Region 1," "Region 2," and "Region 3," and the blower corresponds to the three positions of "Preform Cooling," "Region 1," and "Regions 2 and 3." Note that the initial output settings for the heater and blower can be increments or decrements relative to the settings used for molding or the actual output values. Figure 7 In the example, the heater setpoint and blower setpoint are the actual output values.

[0061] according to Figure 7 The adjustment shown controls the operation of the heating device so that the output of the heater and blower is initially constant (set value: initial state output) (the output of the heater changes in the first and second stages and beyond), and when the difference is within a certain range (in... Figure 7 In the example (within 20°C), the output value changes in a curved shape and eventually becomes the final output value during actual molding. In this way, the output of the heater and blower is switched based on actual measurements, and the output of the heater and blower is continuously adjusted based on the decay curve, starting from the point where the temperature difference between the target ambient temperature and the actual measured temperature becomes equal to or less than the setpoint used to switch the automatic temperature rise control. Therefore, the ambient temperature can approach the target value early and automatically without burdening the operator.

[0062] Hereinafter, a method for manufacturing a resin container using a blow molding apparatus 1 including a control device 600 according to this embodiment will be described. The method for manufacturing a resin container includes: a step of injection molding a preform 10 in an injection molding section 100; a step of conveying the preform 10 formed in the injection molding section 100 to a blow molding section 500; a step of heating the preform 10 while conveying it to the blow molding section 500; and a step of blow molding the conveyed preform 10 into a container 20 in the blow molding section 500.

[0063] The step of injection molding preform 10 is to form N preforms by injecting molten resin into the space formed by the mold closing of the injection core mold 120, the injection neck mold and the injection cavity mold 130 of the injection molding part 100. Figure 2 ).

[0064] The step of conveying the preform 10 formed in the injection molding section 100 to the blow molding section 500 includes a first conveying step, a first transfer step, a second conveying step, and a second transfer step. The first conveying step is the step of removing the preform 10 from the injection molding section 100 by the removal device 150 and further transferring the preform from the removal device 150 to the first flipping section 200 by the preform transfer device 220. Figure 2 The first conveying step is the step of flipping the preform 10 from an upright state to a flipped state by the first flipping part 200 and conveying it to the conveying part 300. Figure 2 ).

[0065] The second conveying step is the step of conveying the preform 10 in the conveying section 300 to the second flipping section 400. Figure 1 In the second conveying step, the first set of first conveying members 310 at the forefront of the parallel drive device 370 is conveyed to the left by the transfer device, and the preform 10 is conveyed to the second flipping section 400 via the continuous conveying area T1 and the intermittent conveying area T2. Figure 1 , Figure 2 ).

[0066] The second conveying step is the step of flipping the preform 10 from the flipped state to the upright state by the second flipping part 400 and conveying it to the second conveying member 530 of the blow molding part 500. Figure 2 However, before the heating unit 360 has completed its temperature rise, the preform 10 is not conveyed to the blow molding section 500, and is removed from the first conveying member 310 via the sprocket 330c. The first conveying member 310 without the preform 10 is then delivered to the parallel drive unit 370 via the sprocket 330c. Figure 1 and Figure 2 ).

[0067] The step of heating the preform 10 is to heat the preform 10 to the optimal temperature for blow molding during transport by the heating device of the heating unit 360 provided in the continuous conveying area T1 of the conveying section 300.

[0068] The steps of blow molding the preform 10 into the container 20 are as follows: the preform 10 is conveyed from the preform receiving position B1 to the blow molding position B2 by the second conveying unit 530, and air is blown into the preform 10 to form the container 20 by closing the blow molding cavity mold and the bottom mold. Through these steps, the container 20 is manufactured.

[0069] Figure 8 An example flow chart of the control method for the blow molding apparatus 1 is shown. Figure 8 As shown, the control method of the blow molding apparatus 1 includes the following steps: acquiring a target value of the temperature inside the heating device by the target value acquisition unit 612 (step S100); acquiring an actual measured value of the temperature inside the heating device by the actual measured value acquisition unit 614 (step S110); calculating the temperature difference between the target value and the actual measured value by the calculation unit 616 (step S120); and adjusting the heating performance and cooling performance of the heating device based on the temperature difference by the adjustment unit 618 (step S130). Additionally, the control method may include adjusting the heating performance and cooling performance of each predetermined region (region 1, region 2, and region 3) within the divided predetermined regions of the heating device by the adjustment unit 618, which acts as a division adjustment unit. Furthermore, the control method may include extending the cycle time in the injection molding section 100 until the temperature inside the heating device reaches the target value by the cycle time control unit 620. For example, the molding cycle may be extended in such a way that when... Figure 6 When 1.5 is entered in the "Cycle" field displayed on the display unit 710, the molding cycle is extended to 1.5 times the default cycle during temperature rise. Furthermore, the extension of the molding cycle can be set to automatically release when the atmospheric temperature reaches the target value.

[0070] Meanwhile, for example, in a blow molding apparatus that includes an injection unit, a safety door is opened when a predetermined operation (such as a purging process) is performed at the start or restart of operation. When the safety door is open, the blow molding apparatus or heating unit stops. After the operation is completed, the operation starts / restarts, but the air inside the heating unit is outside the optimal temperature, and therefore the temperature is raised and regulated. The time required to raise and regulate the temperature of the air, etc., inside the heating unit to a temperature suitable for blow molding is approximately several tens of minutes. Since preforms that have been injection molded and conveyed during this period cannot be heated to the optimal blow molding temperature, they should be discarded (if the injection unit stops, additional time is required until restart). Furthermore, the amount of preforms to be discarded increases for high-productivity blow molding apparatuses (e.g., Class 1.5 machines). Typically, in order to mass-produce containers with consistent quality, it is necessary to heat the preforms similarly under predetermined heating conditions so that the preforms always have the same temperature distribution. The range of predetermined heating conditions is usually narrow, and the temperature of the structure constituting the heating unit (frame, reflector, etc.) also has an effect. Therefore, in order to raise the temperature again and adjust the heating device so that the predetermined heating conditions can be implemented, it is necessary to appropriately raise the temperature of the structure of the heating device and readjust the ambient temperature to fall within the predetermined range.

[0071] The control method of the blow molding apparatus 1 in the above embodiment monitors the temperature of the air (atmosphere) inside the heating device, compares the target value of the ambient temperature with the actual measured value, and adjusts the heating capacity (heater output) and cooling performance (blower output) of the heating device in each case according to the temperature difference. When the temperature difference is large (e.g., -10°C: the actual measured value is 10°C lower than the target value), the heating performance increases and the cooling performance decreases; when the temperature difference is small (e.g., -2°C), the heating performance decreases and the cooling performance increases. Thus, the ambient temperature can be raised and adjusted to the target value in an early stage (the temperature of the heating device can be raised in an early stage), and therefore, the preform 10 can be heated to the optimal blow molding temperature in an early stage. This allows for a reduction in the amount of preforms to be discarded.

[0072] Furthermore, the control method of the blow molding apparatus 1 in this embodiment can optimally adjust the heating and cooling capabilities by setting the heating performance increase rate (heater output increase rate) and cooling performance decrease rate (blower output decrease rate) corresponding to the temperature difference in each predetermined area (area 1, area 2, area 3, etc.) of the heating device.

[0073] Furthermore, the control method of the blow molding apparatus 1 in this embodiment can delay the conveying of the preform 10 in the blow molding apparatus 1 by appropriately extending the molding cycle during the rise / adjustment of atmospheric temperature. Additionally, injection molding can be performed once in multiple default cycles, and therefore, the cycle time can be extended. This allows for a further reduction in the amount of preforms to be discarded.

[0074] Here, we will refer to Figure 9 , Figure 10 and Figure 11 The heating unit 360 of the blow molding apparatus 1 described in a specific manner includes a heating device cooling mechanism (a cooling device for the heating device). Figure 9 The internal aspects of the heater housing 800 provided for the heating unit 360 in a particular manner are shown. Figure 10 The external aspect of the heater housing 800 provided for a heating unit 360 in a particular manner is shown. Figure 11 The conduit line for introducing cooling air into the heater box 800 is shown.

[0075] The heater housing 800 has a heating device on its inner side. The heating device includes, for example, a quartz heater (heating element, heating lamp) and a reflector (reflector plate). In this example, the quartz heater and reflector are arranged so that along the conveyor section 300 (where the quartz heater and reflector are not in...) Figure 9 and Figure 10 (As shown in the image) The precast component 10 is sandwiched in the middle.

[0076] The heater housing 800 is provided separately from the aforementioned blower, with a duct 810 for supplying cooling air to the reflector. The duct 810 has multiple nozzles 812 for injecting cooling air into the interior of the heater housing 800. The nozzles 812 are arranged at substantially equal intervals throughout the duct 810. The nozzles 812 are located behind the reflector (not shown). The reflector is cooled from the rear by the cooling air injected from the nozzles 812. The duct 810 has multiple connections 814 on the outside of the heater housing 800 for connecting to ducts for introducing the cooling air. Figure 10 The diagram shows three connecting portions 814, which are provided to correspond to each of the three equal divisions of the heater box 800. At least the same number of connecting portions 814 as the divisions of the heater box 800 are provided on the outer side of the heater box 800.

[0077] exist Figure 11The illustrated conduit (pneumatic circuit) shows a heater housing 800, an accumulator 820, a first air pressure source 830, and a second air pressure source 840. The accumulator 820 is connected to the first air pressure source 830 via a first flow control valve 850 and a first solenoid valve 860, and is configured to store pressurized gas (pressurized gas, compressed air) supplied from the first air pressure source 830. The first solenoid valve 860 is a normally closed solenoid valve. Therefore, when the first solenoid valve 860 is energized, the accumulator 820 operates to open, allowing pressurized air to be supplied from and stored in the first air pressure source 830, and when the first solenoid valve 860 is not energized, the accumulator automatically operates to close, preventing the stored air from being discharged to the first air pressure source 830 side (in the event of a power failure, pressurized air is not supplied to the accumulator 820). Note that the first air pressure source 830 and the second air pressure source 840 supply gas pressurized, for example, at 1.2 MPa to 2.0 MPa, to the conduit. In addition, the accumulator 820 stores, for example, 0.2 L to 0.5 L of pressurized gas.

[0078] The heater housing 800 is connected to the second air pressure source 840 via a pilot-operated valve (third solenoid valve) 870. Specifically, the piping allows air (pressurized gas) for cooling to be supplied from the second air pressure source 840 to each connection 814 of the pipe 810 provided for the heater housing 800.

[0079] Pilot-operated valve 870 is a normally closed valve. Pilot-operated valve 870 is connected to accumulator 820 via a second solenoid valve 880. The pipe extending from the second solenoid valve 880 to pilot-operated valve 870 branches into two, one connected to pilot-operated valve 870 and the other connected to a second flow control valve 890. Note that the second flow control valve 890 can be located at a midpoint of the pipe extending from the second solenoid valve 880 toward pilot-operated valve 870. The second solenoid valve 880 is a normally open solenoid valve. Therefore, when the second solenoid valve 880 is not energized, accumulator 820 automatically operates to open to supply air to pilot-operated valve 870, and when the second solenoid valve 880 is energized, accumulator operates to close to prevent air supply to pilot-operated valve 870. The second flow control valve 890 is configured to control the flow rate of air supplied from accumulator 820 to pilot-operated valve 870.

[0080] When air is supplied from the accumulator 820 to the pilot-operated valve 870, the pilot-operated valve 870 opens, allowing cooling air to be introduced from the second air pressure source 840 into the heater housing 800, and the cooling air is then injected from the nozzle 812 in the heater housing 800 onto the rear side of the reflector. This cools the reflector.

[0081] The aforementioned cooling mechanism is particularly effective in the event of a power failure. The operation of the cooling mechanism in the event of a power failure will be described below. First, the first solenoid valve 860 is opened to pre-store pressurized gas of predetermined performance in the accumulator 820 when energized (the first solenoid valve 860 can be closed after storage). When the blow molding apparatus 1 is not energized due to a power failure, the first solenoid valve 860 is automatically closed and the second solenoid valve 880 is automatically opened. As a result, the air stored in the accumulator 820 is supplied to the pilot-operated valve 870, causing the pilot-operated valve 870 to automatically switch from the closed state to the open state. As a result, pressurized gas from the second air pressure source 840 is automatically supplied to the conduit line and injected as cooling air from the nozzle 812 of the pipe 810 to the rear side of the reflector. In addition, since the air flow rate supplied from the accumulator 820 to the pilot operating valve 870 is controlled by the second flow rate control valve 890, the pilot operating valve 870 can remain open for a predetermined time, and in the event of a power failure, it can cool the reflector in the heater box 800 for a predetermined time.

[0082] Because the blower is inoperable in the event of a power failure, the ambient temperature in the heater box 800 rises significantly due to the residual heat of the reflector. If the preform is abnormally heated by the high-temperature atmosphere, it may collapse or melt and come into contact with the quartz heater, potentially damaging the heating device or causing a fire. The aforementioned cooling mechanism can mitigate the fault by automatically cooling the reflector with air in the event of a power failure. Furthermore, since the air supply from the accumulator 820 is stopped and the pilot-operated valve 870 is automatically closed after a predetermined time, the supply of air for cooling from the second air pressure source 840 is also automatically stopped. Thus, the compressed air stored in the second air pressure source 840, which is composed of, for example, a compressor, does not need to be used up in the event of a power failure, and the remaining compressed air can be effectively used during startup. Moreover, since each valve on the duct can be switched without power, an expensive uninterruptible power supply (UPS) is not required.

[0083] It should be noted that the present invention is not limited to the above embodiments, and can be freely modified and improved as appropriate. Furthermore, the material, shape, size, value, form, quantity, and arrangement of each constituent element in the above embodiments are arbitrary, and there are no particular limitations as long as the present invention can be realized.

[0084] For example, in the embodiments described above, the manner in which various functional units are installed in the processor of a single device has been described. However, the various functional units can be distributed and installed in the processors of multiple devices via a local network or the Internet. Furthermore, in the above embodiments, the display unit 710 and the input unit 720 have been described as separate units, but they can be configured as a single functional unit via a touch panel or the like, allowing for input and display.

[0085] This application is based on Japanese patent applications filed on July 17, 2020 (patent application number 2020-123156) and September 2, 2020 (patent application number 2010-147627), the entire contents of which are incorporated herein by reference. Furthermore, all references cited herein are also incorporated herein by reference.

[0086] List of reference numerals

[0087] 1: Blow molding device; 10: Preform; 20: Container; 100: Injection molding section; 200: First flipping section; 300: Conveying section; 310: First conveying component; 360: Heating unit; 400: Second flipping section; 500: Blow molding section; 600: Control device; 612: Target value acquisition unit; 614: Actual measurement value acquisition unit; 616: Calculation unit; 618: Adjustment unit; 620: Cycle time control unit; 700: Input / output device.

Claims

1. A method for controlling a manufacturing apparatus configured to manufacture resin containers by blow molding preforms, the control method comprising: A target value for the temperature inside a heating device is obtained, the heating device being configured to heat the preform to an optimal temperature for blow molding. Obtain the actual measured value of the temperature inside the heating device, detected by sensors arranged inside the heating device; Calculate the temperature difference between the target value and the actual measured value; The input of the temperature difference between the target value and the actual measured value, as set by the operator, and the set value of the index representing the degree of adjustment of the heating performance and cooling performance of the heating device; as well as The heating and cooling performance of the heating device corresponding to the temperature difference is adjusted based on the temperature difference and the set value.

2. The control method of the manufacturing apparatus according to claim 1, comprising adjusting the heating and cooling performance of each predetermined region in the plurality of predetermined regions divided in the heating apparatus.

3. The control method for the manufacturing apparatus according to claim 1 or 2, wherein, The manufacturing apparatus includes an injection molding section configured to injection mold preforms, and The cycle time in the injection molding section is extended until the temperature inside the heating device reaches the target value.

4. A method for manufacturing a resin container, comprising: Injection molding of preformed resin-insulated parts; and Resin containers are manufactured by blow molding a preform that has been formed in injection molding. in, The control method of the manufacturing apparatus according to any one of claims 1 to 3 is performed so as to heat the preform formed in injection molding to an optimal temperature for blow molding.

5. A control device for a manufacturing apparatus configured to manufacture resin containers by blow molding preforms, the control device comprising: A target value acquisition unit is configured to acquire a target value of the temperature inside a heating device, the heating device being configured to heat the preform to an optimal temperature for blow molding. An actual measurement value acquisition unit is configured to acquire actual measurement values ​​of the temperature inside the heating device detected by sensors arranged inside the heating device; A calculation unit configured to calculate the temperature difference between the target value and the actual measured value; The receiving unit is configured to receive inputs from the operator of the temperature difference between the target value and the actual measured value, and the set value of an index representing the degree of adjustment of the heating and cooling performance of the heating device; as well as An adjustment unit adjusts the heating and cooling performance of the heating device corresponding to the temperature difference based on the temperature difference and the set value.

6. The control device for the manufacturing apparatus according to claim 5, comprising a segmentation adjustment unit configured to adjust the heating and cooling performance of each predetermined region in a plurality of predetermined regions divided in the heating apparatus.

7. The control device for the manufacturing apparatus according to claim 5 or 6, wherein, The manufacturing apparatus includes an injection molding section configured to injection mold preforms, and The manufacturing apparatus is controlled to extend the cycle time in the injection molding section until the temperature inside the heating device reaches the target value.

8. An apparatus for manufacturing a resin container, comprising: The injection molding section is configured to injection mold a base resin preform. A heating unit, comprising a heating device configured to heat the preform to an optimal temperature for blow molding; A blow molding section configured to manufacture resin containers by blow molding the preform heated in the heating unit; as well as The control device for the manufacturing apparatus according to any one of claims 5 to 7.

9. The resin container manufacturing apparatus according to claim 8, further comprising a display unit configured to display the target value and the actual measured value.

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