JP6999768B1 - Temperature control device and blow molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature control device of a blow molding station which contributes to manufacturing a bottle with a handle having a large difference in thickness between a handle and a bottle body. SOLUTION: In a temperature control device attached to a blow molding machine provided with a turntable in which an injection device, a temperature control device and a blow device are sequentially provided on a circumferential surface, the temperature control device is used as a bottle preform. It is a temperature control device including an infrared lamp that extends and enters and is separated from the inner wall of the bottle preform. As a result, after the bottle preform is injection-molded, the temperature control work space of the bottle preform can be expanded, and the deterioration of the yield caused by the difference in thickness between the handle of the bottle with the handle and the bottle body can be reduced. .. [Selection diagram] Fig. 2

Description

The present invention relates to a temperature control device for a blow molding station, which contributes to the production of a bottle with a handle in which the difference in thickness between the handle and the bottle body is large.

Blow molding machines that manufacture bottles can be divided into one-stage molding and two-stage molding. The operating principle of a one-stage blow molding machine is that the injection molded bottle preform is blow molded immediately before it is cooled. Therefore, it can be applied only to a bottle body structure having a simple structure and having the same thickness of the bottle bodies.

The two-stage molding injection device and the blow device are usually located independently and on different production lines (or positions), and are further molded sequentially by temperature control to each part of the bottle body, for example, a handle or a bottle body. To complete. Since a temperature control device is installed between the injection device of this type of blow molding machine and the working position of the blow device, energy is consumed.

The temperature control device can maintain the internal temperature of the bottle preform by, for example, the temperature control core rod extending into the bottle preform and coming into contact with the inside of the bottle preform, and the bottle preform can be maintained. Can maintain the external temperature of the bottle preform by being placed in a heat insulating pot at the same time. In this type of temperature control device, an anti-adhesive coating layer containing mainly particle materials such as Teflon (registered trademark), phosphorus, and high temperature resistant nickel oxide may be provided on the surface in contact with the bottle preform, but it is hydrophobic. The heat resistance of Teflon is less than 200 ° C., and the coating layer may lose its function due to impact.

If a bottle with a handle is manufactured for a one-stage blow molding machine, the bottle preform of the bottle body and the handle to be combined are formed at the stage of injection molding the bottle preform, and then the handle is exposed. The surface can be smoothed by cooling, and then blow molding can be performed on the bottle preform to form a bottle body. However, since the plastic molding conditions of the handle and the bottle preform are different, the position of the temperature control device must be adjusted in order to prevent the temperature of the injection-molded bottle preform from becoming too low and deforming. ..

As shown in FIG. 1, a certain one-stage molding blow molding machine is based on a ring-shaped turntable 11 installed in a workstation 10, and a rotary joint 50 is provided inside the ring-shaped turntable 11. An injection station 20, a temperature control station 30, a blow station 40, and a take-out station 60 are defined in the circumferential direction of the outer ring surface of the ring-shaped turntable 11. The turntable 11 is used to sequentially supply the transfer table 12 (sample holder 121) to the four workstations.
In the manufacturing process by this device, the bottle preform 121A with a handle is sequentially formed by the injection molding unit 21 at the stage of the injection station 20, the bottle preform 121A is sent to the temperature control station 30, and the bottle preform 121A is blown. It is supplied to the station 40 to form a bottle 121B with a handle, and finally the finished product is moved by the clamp 61 at the take-out station 60.
In this type of blow molding machine, the rotary joint 50 provides a liquid or gas as a heat medium and supplies the heat medium (which may be through a flow path) so as to surround the outer ring surface of the turntable 11. The temperature controllability of the bottle preform 121A can be enhanced, and this arrangement contributes to lowering the handle temperature and maintaining the temperature of the bottle preform.
However, if the difference in thickness between the handle of the bottle with the handle and the bottle body is too large, when the handle is cooled, the joint position between the handle and the main body of the bottle preform (the position of the handle joint 135 in FIG. 3). (See) shrinks, the handle breaks, and the yield tends to decrease.

The present invention is a temperature control device attached to a blow molding machine provided with a turntable in which an injection device, a temperature control device and a blow device are sequentially provided on the circumferential surface, wherein the temperature control device is a bottle preform. Provided is a temperature control device comprising an infrared lamp that extends into and away from the inner wall of the bottle preform.

By performing the work of controlling the temperature or heating the inner wall of the bottle preform with the infrared lamp, it is possible to have a wide working space and the temperature gradient unevenness is less likely to occur. When manufacturing a bottle with a handle using the above temperature control device, the infrared lamp heats a part of the bottle preform to prevent the internal shrinkage phenomenon of the handle caused by the temperature difference being too large, and in manufacturing. Yield can be improved.

Preferably, the infrared lamp has a wavelength range of 0.75 μm to 1000 μm, and it is preferable to select an infrared lamp having a short wavelength, and the infrared lamp can be attached to an angle adjusting device to form an irregular bottle preform. On the other hand, temperature control work can be performed. In addition to this, the temperature control device further includes a heat insulating cover provided on the inner wall and the outer wall of the bottle preform together with the temperature control device, and the heat insulating cover is separated from the outer wall of the bottle preform, and a plurality of heat insulating covers are provided. By providing a temperature control section, the light irradiation invalid area of the infrared lamp is supplemented.

The present invention further comprises a turntable provided with a plurality of transport tables for moving the bottle preform having a handle, and an injection station and a radiant heat source are provided on the circumferential surface of the turntable. Provided is a blow molding machine, which is sequentially provided with a temperature control station and a blow station provided with the above-mentioned temperature control device that does not provide a heated gas as a heat source.

It is a schematic diagram of a blow molding machine. It is a schematic diagram of each element of a temperature control device. It is a positional schematic diagram of each part of a bottle preform. It is 1st operation schematic diagram of the temperature control device. It is a 2nd operation schematic diagram of a temperature control device.

FIG. 2 illustrates the arrangement relationship of each element of the temperature control device of the temperature control station of the blow molding machine, and the temperature control device is attached to the temperature control station 30 of the blow molding machine shown in FIG. The blow molding machine is provided with a ring-shaped turntable 11, and the outer ring surface of the ring-shaped turntable 11 is defined with four workstations 10 in the circumferential direction, which are an injection station 20, a temperature control station 30, a blow station 40, and a blow station 40, respectively. The take-out station 60. The turntable 11 sequentially supplies the transfer table 12 (sample holder 121) to the four workstations 10 to perform at least four processes of bottle preform injection, temperature control, blow molding, and finished product removal. Used.

See also FIGS. 3 and 4. In this embodiment, the blow molding machine is used to manufacture a bottle with a handle. Therefore, after the process of injection molding the bottle preform 121A, the outer portion of the mouth portion 14 of the bottle preform 121A and the handle portion 13 are positioned on the sample holder 121, and the main body portion 15 of the bottle preform 121A is primary. The bottle preform 121A can be suspended in the air, and a part of the handle portion 13 of the bottle preform 121A can be exposed to the air to lower the temperature.

The temperature control station 30 is provided with a temperature control device based on the position of the sample holder 121. In the present embodiment, the infrared lamp 31 is attached below the drive unit 32, and one of the sample holders 121 is infrared rays. It is positioned below the lamp 31. As a result, the infrared lamp 31 moves with respect to the bottle preform 121A, enters from the mouth portion 14 of the bottle preform 121A, and extends toward the bottom portion 16, thereby relating to the inner wall of the bottle preform 121A. Can provide thermal energy. The temperature control device here does not provide a heated gas as a heat source.

By directly heating the bottle preform with the infrared rays of the infrared lamp 31, the effective heating range of the inner wall of the bottle preform 121A can be expanded. Compared to the temperature control core rod of contact type heating, the one that performs non-contact type heating using the infrared lamp 31 has a wider work space (work window), and the possibility of adjusting the process parameters is further expanded.

See FIGS. 2-5. In the present embodiment, the heat insulating cover 35 is further provided below the sample holder 121, and the heat insulating cover 35 is provided above the drive unit 36 so that the heat insulating cover 35 moves with respect to the bottle preform 121A. Therefore, the main body 15 of the bottle preform 121A suspended in the air can be housed in the heat insulating cover 35. Therefore, the main body portion 15 and / and the bottom portion 16 can be maintained at a suitable working temperature by keeping the heat insulating cover 35 warm or heating.

Further, the bottom 16 is kept warm by the temperature control section 352 of the heat insulating cover 35 with respect to the light irradiation invalid region distance L3 (about 20 to 30 mm) between the end of the infrared lamp 31 and the bottom 16 of the bottle preform 121A. be able to. Since the heat insulating cover 35 is also separated from the outer wall of the bottle preform 121A, a tungsten wire as a heat retaining heat source is provided on the outside of the heat insulating cover 35 and used to maintain the temperature of the outer wall of the bottle preform 121A. .. However, on the premise that it can be operated, the heat source of the heat insulating cover 35 can be another infrared heating device.

In the present embodiment, the infrared lamp 31 and the heat insulating cover 35 are individually located in independent drive units and move up and down with respect to the bottle preform, or based on desired parameters such as heating time. Can be adjusted. Therefore, the heat insulating cover 35 defines a plurality of temperature control sections 351, 352 and is used to maintain the temperature of a part of the bottle preform 121A or to heat the bottle preform 121A, and the temperature difference is too large. It is also possible to prevent the internal shrinkage phenomenon of the handle that occurs in.

Further, in the present embodiment, the distance between the infrared lamp 31 and the inner wall of the bottle preform 121A is between L1 and L2. Of these, L1 is the distance at which the infrared lamp 31 heats the bottle preform 121A to cause temperature gradient unevenness, and is determined by the characteristics of the bottle preform material and the irradiation power of the infrared lamp, and L2 is the infrared lamp. This is the maximum distance between the lamp and the inner wall of the bottle preform when 31 extends and enters the bottle preform 121A. In other words, the infrared lamp 31 can perform the heating work inside the bottle preform and at a distance between L1 and L2 from the side wall of the bottle preform, and has a wide working space. Is.
On the other hand, if the (annular) infrared lamp is attached to the outside of the heat insulating cover, the distance between the heat insulating cover and the bottle preform is less than L1, and uneven temperature gradient is likely to occur.

Infrared lamps have wavelengths near infrared (wavelengths in 0.75 μm to 1.5 μm), mid-infrared (wavelengths in 1.5 μm to 5.6 μm), or far infrared rays (wavelengths in 5.6 μm to 1000 μm). ), But it is preferable to select a near-infrared lamp. Further, the infrared lamp is a vertical IR lamp, and the type of the lamp can be selected from an IR halogen lamp, an IR quartz tube or an IR black heater based on the above wavelength range.

The blow molding machine described above can be used in the area of manufacturing bottles with handles, and if the thickness of the injection-molded handle is X and the thickness of the bottle body after blow molding is Y, X is It is 4 to 15 times that of Y.

In the present embodiment, on the premise that the temperature control device is attached to the temperature control station 30 of the blow molding machine shown in FIG. 1 or does not affect the manufacturing process, the temperature control station 30 is a temperature control unit related to the rotary joint 50. Can be replaced directly with. In addition, the temperature control device may be attached to another blow molding machine for one-stage molding. The blow molding machine described above is not limited to the production of bottles with handles, and is applied to blow molding machines such as elliptical containers and non-circular containers that require special control of the temperature of the bottle preform. May be good.

When the temperature control device is applied to an elliptical container or a non-circular container, the mounting holder 311 of the infrared lamp 31 is further provided with an angle adjusting device, and when the infrared lamp 31 enters the bottle preform 121A by the angle adjusting device. The contour is non-uniform by adjusting the angle of the infrared lamp 31 so that the infrared lamp 31 irradiates and heats only a part of the area, or by making the heating degree of a specific area of the inner wall of the bottle preform 121A different. It can be applied to the manufacture of bottles with various handles. Since the infrared lamp 31 can provide a wide work window, it is possible to make parameter adjustment relatively easy.

In the present embodiment, after the bottle preform is formed, the connection position between the handle portion 13 and the mouth portion 14 of the bottle preform 121A (that is, the handle joint portion 135 corresponds to the handle material injection port at the time of injection molding). Further installs a sheet metal shield. The material in this region reaches a temperature of 150 ° C. or higher during injection molding, the solidified layer becomes very thin, is susceptible to lamp radiation, causes breakage, and the solidified layer is easily broken and deformed. Therefore, in order to avoid infrared irradiation, a sheet metal shield is required during the temperature control process.

In a specific embodiment, taking a polyester copolymer material (PET, TRITAN) as an example, the temperature of the bottle preform and the handle is lowered when the injection molding step is completed. Of these, when the handle temperature drops to 21 ° C, the temperature at the handle inlet also drops to 21 ° C, and then shifts to the temperature control device.

The infrared lamp uses a voltage of 220 V to 380 V and a power of 500 w to 3 kW, and controls the infrared lamp to output 80% of the power (P = IV) based on the glass transition temperature Tg of the polyester copolymer material. .. The output power is determined by the intensity of the lamp's infrared output, and the temperature of the bottle preform is controlled to be about 10 ° C to 30 ° C higher than Tg (that is, Tg + 10 ° C to Tg + 30 ° C), and the infrared lamp is bottled vertically. By putting it in the inner wall of the remodeling, leaving a space between the infrared lamp and the bottle preform, and setting the temperature of the heat insulating cover to (Tg-10 ° C to Tg + 30 ° C), softening blowing is performed. Subsequently, a blow molding step is performed.

Under the above-mentioned manufacturing conditions, a bottle with a handle having a solid handle thickness of 10 to 25 mm and a blow-molded bottle body thickness of 2 mm is manufactured, and a shrinkage phenomenon does not occur at the handle bonding position. Can be. In addition, those skilled in the art can improve manufacturing yields by selecting other types of crystalline materials (eg: PETG, PP) and adjusting the power of the infrared lamp and the distance between the lamp and the bottle preform. Can be made to.

10 Workstation 11 Ring-shaped turntable 12 Conveyance table 121 Sample holder 121A Bottle preform 121B Bottle with handle 13 Handle part 135 Handle connection part 14 Mouth part 15 Main body part 16 Bottom part 20 Injection station 21 Injection molding unit 30 Temperature control station 31 Infrared Lamp 311 Mounting holder 32, 36 Drive unit 35 Heat insulation cover 351, 352 Temperature control section 40 Blow station 50 Rotating joint 60 Extraction station 61 Clamp L1, L2 Distance X Thickness

Claims (6)

In a temperature control device attached to a blow molding machine equipped with a turntable in which an injection device, a temperature control device, and a blow device are sequentially provided on the circumferential surface.
The temperature control device is attached to an angle adjusting device, and has an infrared lamp that extends into the bottle preform and is separated from the inner wall of the bottle preform, and a heat insulating cover provided on the outer wall of the bottle preform. Including, the bottle preform has a handle integrally formed on the injection device, the thermal insulation cover has a plurality of temperature control sections, and one of the plurality of temperature control sections is said. Characterized by being located at the bottom of the bottle preform,
Temperature control device. The distance between the infrared lamp and the inner wall of the bottle preform is between L1 and L2, L1 is the distance at which the temperature gradient unevenness occurs in the bottle preform with the infrared lamp, and L2 is the distance where the infrared lamp extends. The temperature control device according to claim 1, wherein the maximum distance between the infrared lamp and the inner wall of the bottle preform when the infrared lamp enters the bottle preform. The temperature control device according to claim 1, wherein the infrared lamp has a wavelength range of 0.75 μm to 1000 μm. Claim 1 is characterized in that X is 4 to 15 times Y, where X is the thickness of the handle and Y is the thickness of the bottle body after blow molding the bottle preform. The temperature control device described. The temperature control device according to claim 1, wherein the infrared lamp and the heat insulating cover are individually located in independent drive units. It is equipped with a turntable provided with multiple transport tables for moving bottle preforms with handles.
An injection station, a temperature control station provided with the temperature control device according to any one of claims 1 to 5, and a blow station are sequentially provided on the circumferential surface of the turntable, and the bottle preform is a bottle preform. It is characterized by having a handle portion integrally formed in the blow station.
Blow molding machine.

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