JPH0241404B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an injection stretch blow molding machine that can perform secondary processing following stretch blow molding of a blow molded product.

Hollow molded products such as stretch-blow molded synthetic resin bottles have superior transparency and strength compared to blow molded hollow molded products, and are becoming widely used as containers for various contents, including beverage bottles. .

In addition, with the expansion of applications, there is a demand not only for the strength of hollow molded products to be improved, but also for products with external shapes that match the contents.In the case of carbonated beverage bottles, a separate A reinforced base cap is fitted to improve the strength of the bottom.

This fitting of the base cup requires a device that fits and presses the base cup coated with adhesive on the bottom of the hollow molded product, and is carried out by taking the hollow molded product out of the molding machine and then feeding it into the device. The drawback was that it was time-consuming and easy to cause product loss.

Therefore, the inventor developed a setting device for inserting a base cup into a stretch blow mold and fitting the base cup at the same time as the stretch blow molding of a hollow molded product. ,
With the current distributor, it is difficult to reliably supply the required number of base cups to the setting device at all times, and we have come to the conclusion that it is necessary to improve the distributor in order to put it into practical use. It's not enough to do that,
Large bottles for carbonated drinks are fitted with base cups.

This invention was developed in view of the above-mentioned circumstances, and includes attaching a base cup to a hollow molded product by injection molding. The present invention provides a new injection stretch blow molding machine that can perform molding continuously in the same machine.

The present invention for the above purpose provides a molding machine that continuously performs injection molding of a bottomed parison to removal of a stretch-blow-molded hollow molded product by one rotation of an intermittent rotating rotary disk. A secondary processing station for injection molding of synthetic resin is installed at
The present invention is characterized in that it is configured to have a secondary processing mold and a secondary injection device disposed in this secondary processing station so that partial injection molding can be performed on a hollow molded product.

The present invention will be explained in detail below using illustrated examples.

In the figure, reference numeral 1 denotes a board provided at a required interval above the machine stand 2, and a drive device 3 is fixed to the center of the top surface. This drive device 3 is for intermittently rotating a horizontal rotary disk 4 provided close to the lower side of the substrate 1, and is a commercially available device that operates electrically or hydraulically, and the drive shaft 5 is a transmission means. It communicates with the rotary disk 4 via.

Further, around the lower surface of the rotary disk 4, five neck molds 6, 6 are mounted at regular intervals, and springs 7, 7 are applied so that they can be freely opened and closed in the radial direction. The positions where each of the neck molds 6, 6 stop are five operation stations: injection molding station A, temperature adjustment station B, stretch blow molding station C, secondary processing station D, and take-out station E. Although not shown in the figure, the board 1 and rotary disk 4 in the parts corresponding to each station have a required number of holes 8, which respectively guide the various cores and mold opening members downward, which are operated by a lifting device provided on the board in that part. 8a is bored.

Furthermore, the injection molding station A includes:
An injection device 9, an injection mold and a mold clamping device are provided, and a temperature adjustment station B is provided with a temperature adjustment pot that can be moved up and down. Further, the stretch blow molding station C is provided with a blow mold 10 and its hydraulic opening/closing devices 11, 11 in the radial direction.

As shown in FIG. 2, the blow molding mold 10 has the following features:
The neck mold 6, which is composed of a pair of split molds that sandwich and close the neck mold 6, and which holds the bottomed parison 12 in the center of the mold, is connected to the holes 8, 8a of the substrate 1 and the rotary disk 4.
A blowing core 13 descending from above the substrate is inserted through the blowing core 13, and the bottomed parison 12 is stretched in the axial direction by a stretching rod 14 installed in the blowing core 13, and is expanded by compressed air from the blowing core 13. A hollow molded product 15 is obtained.

Next, the secondary processing station D is provided with a secondary processing mold 16, its hydraulic opening/closing device 17, and a secondary injection device 18 in the radial direction. As shown in FIG. 3, the cavity of the secondary processing mold 16 is composed of a pair of split molds formed identically to the cavity of the blow mold 10, except for the lower part of the cavity, and It has a structure in which the hollow molded product 15 that has been held and transferred is held together with the neck mold 6. Further, a secondary blowing core 19 is inserted into the neck mold 6 through the holes 8 and 8a of the substrate 1 and the rotary disk 4, and from the secondary blowing core 19 the hollow molded product 1 is inserted.
Compressed air higher than the injection pressure is blown into the hollow molded product 15 to maintain it as an injection core.

Further, the secondary injection device 18 is installed from the side of the machine stand 2 into the inside, and the hot runner block 1
The nozzle 20 protruding from the bottom 9 is touching the center of the bottom mold 21 of the secondary forming mold 16 through the machine floor plate 2a, and there is a gap between the bottom mold 21, the lower part of the cavity, and the bottom of the hollow molded product 15. A cavity is formed in which the base cap 22 is formed.

Reference numeral 23 denotes a lifting device for the secondary injection device 18, which includes a seat plate 26 connected to a piston rod 25 of a cylinder 24 using hydraulic or pneumatic pressure, and
Seat plate guide rod 2 supported by a fixed plate 27 integrated with 4
A secondary injection device 18, which is composed of a seat plate 26 and fixed thereon, is raised and lowered in accordance with the opening and closing of the mold 16 for secondary processing. At this time, the bottom mold 21 also moves up and down between the floor plates together with the nozzle 20.

In the above molding machine, the rotary disk 4 is configured to rotate counterclockwise by 72 degrees. Since this intermittent rotation can be easily achieved by using various commonly employed devices, the details thereof will be omitted.

First, the bottomed parison 12 is molded at the injection molding station A, and the bottomed parison 12 is held in the neck mold 6 and transferred to the temperature adjustment station B. After temperature adjustment, the bottomed parison 12 is transferred to the stretch blow molding station C. Then, after the mold is closed, the hollow molded product 15 is stretch-blown molded as shown above.

Next, the hollow molded product 15 is held in the neck die 6 and transferred to the center of the secondary processing mold 16 which is in the open state of the secondary processing station D, and is further closed to form the secondary processing mold 16. It is held by 6. At this time, the injection device 18 rises, and the bottom mold 21 rises together with the nozzle 20, forming a cavity around the bottom of the hollow molded product 15.

A secondary blown core 19 is inserted into the neck mold 6, and compressed air is blown into the hollow molded product 15 to maintain an internal pressure higher than the injection pressure, thereby converting the hollow molded product 15 into an injection core. Thereafter, resin is injected around the bottom of the hollow molded product 15, and the base cup 22 is secondarily molded.

The hollow molded product 15 subjected to the secondary processing as described above is transferred to the take-out station E after opening the mold, and is taken out of the machine by opening the neck mold 6.

The above explanation is based on base cup 2 as an example of secondary processing.
Although the injection molding described in No. 2 has been described above, injection molding is not limited to the base cup 22, and can mold a secondary processed product of any shape depending on the purpose or shape of the hollow molded product 15.

As described above, this invention provides a secondary processing station D between the stretch blow molding station C and the take-out station E, and closes the hollow molded product 15 as an injection core in this operation station.
The next processing mold 16 and the secondary injection device 18 are provided to enable continuous injection molding of bottomed parisons, stretch blow molding of hollow molded products, and secondary injection molding of base cups, etc. There is less product loss than in the case where secondary processing is performed after taking out the blow molded product, and secondary processing equipment is not required, labor can be saved and product costs are reduced.

Furthermore, the molding machine itself has the advantage that by adding one operating station, other operating stations can be used as they are, and the structure is not particularly complicated.

[Brief explanation of the drawing]

The drawing shows one of the injection stretch blow molding machines according to the present invention.
1 is a plan view, FIG. 2 is a longitudinal sectional view of a stretch blow molding station, and FIG. 3 is a longitudinal sectional view of a secondary processing station. 1... Board, 2... Machine stand, 3... Drive device, 4
...Rotary disk, 6... Netsuku type, 9... Injection device,
10... Blow molding mold, 12... Bottomed parison,
13... Blowing core, 14... Stretching rod, 15...
...Blow molded product, 16...Mold for secondary processing, 18...
...Secondary injection device, 19...Secondary blowing core, 20...
... Nozzle, 21 ... Bottom mold, 22 ... Base cap. A... Injection molding station, B... Temperature adjustment station, C... Stretch blow molding station, D... Secondary processing station, E... Taking out station.

Claims (1)

[Claims] 1. In an injection stretch blow molding machine, each operation station required for taking out a stretch blow molded hollow molded product from injection molding of a bottomed parison is arranged in order at a stop position of a neck type attached to a rotating member that rotates intermittently. A secondary processing station for the hollow molded product is provided at the neck mold stop position between the stretch blow molding station and the take-out station, and the secondary processing mold closes the hollow molded product as an injection core in the secondary processing station. and a secondary injection device,
An injection stretch blow molding machine that can perform partial injection molding of hollow molded products following stretch blow molding.