TW201431666A - Blowing molding method and device - Google Patents

Abstract

A blowing molding method and device are disclosed, the method comprising: setting a first transport path and a second transport path which operate continuously; forming at least one bottle blank on the first transport path by injection molding; then, heating the bottle blank on the second transport path and using a pre-blowing mold to blow-molding the bottle blank into a semi-finished product; afterwards, heating the semi-finished product on the second transport path; and finally using a blow-molding mold on the second transport path to blow-mold the semi-finished product into a finished product, thereby increasing the product quality, reducing the defective rate and increasing product capacity.

Description

Blow molding method and device

The present invention relates to a blow molding process, and more particularly to a blow molding method and apparatus.

Existing plastic containers are usually manufactured by a blow molding method. There are two common methods of blow molding. The first method is to use an injection machine to first shoot out the plastic and form the preform. Then store the preforms in the warehouse one by one, and then place the preforms before shipment. Taking out and heating the preform to a forming temperature through a conveying device arranged in a pull-blow molding machine, and then placing the heated preforms into a forming mold one by one, and passing the high-pressure gas After the preform is blown into the shape of the inner wall of the mold, the finished product of the plastic container is completed.

The second way is to blow the preform into the inner wall of the forming mold by directly spraying out the plastic and forming the preform after a preforming blow molding machine, and simultaneously heating the preform to the forming temperature and using a forming mold. The finished shape.

However, the first blow molding method is limited in that the cooling time of the injection machine is too long, and the preform is heated from room temperature to its forming temperature, and the heating time is long because the temperature difference is large. At the same time, the above two forms The method is that the preform is blow molded into a finished product at one time, and it is easy to excessively stretch the preform, thereby causing uneven thickness and, therefore, the production product has a high defect rate.

Accordingly, it is a first object of the present invention to provide a blow molding method which has a handle integrated and which can increase productivity and reduce a defective rate.

Thus, a blow molding method of the present invention comprises the following steps: Step 1: setting a first conveying path for continuous operation and a second conveying path for engaging the first conveying path. Step 2: Injection of plastic on the first conveying path and injection molding to form at least one preform. Step 3: After the preform is transferred from the first conveying path to the second conveying path, the preform is heated. Step 4: Pre-blowing the preform into a half finished product using a pre-blow mold located on the second conveying path. Step 5: transporting the semi-finished product on the second transport path and heating the semi-finished product, and step 6: blow molding the semi-finished product into a finished product by using a blow molding die located on the second transport path.

A second object of the present invention is to provide a blow molding apparatus having a handle integrally formed and capable of improving productivity and reducing defective rate.

A blow molding apparatus according to the present invention comprises a conveying unit, a preform injection mold, a first heating unit, a pre-blowing mold, a second heating unit, and a blow molding mold.

The conveying unit includes a first conveying path for continuous operation and a second conveying path for engaging the first conveying path. The preform injection mold is disposed on the first conveying path and is configured to form at least one preform. The first heating unit is disposed on the second conveying path and heats the preform. The pre-blowing mold is disposed on the second conveying path and is used to pre-bloat the preform into half of the finished product. The second heating unit is disposed on the second conveying path and heats the semi-finished product. The blow molding die is disposed on the second conveying path and is used to blow the semi-finished product into a finished product.

The utility model has the advantages that the preform unit transmits the preform when the preform has a residual temperature, and the preform is continuously heated by the first heating unit to reduce the difference from the forming temperature, and the pre-use is utilized. The blow mold first pre-blowing the preform into the semi-finished product, and then blown into the finished product through the blow molding die, thereby avoiding the problem that the preform is unevenly caused by one over-stretching, thereby saving heating operation time. Increase production capacity and reduce product defect rate.

1‧‧‧Plastic injection unit

11‧‧‧ shots

12‧‧‧ shots

13‧‧‧ shots

2‧‧‧ preform injection mold

20‧‧‧Clamping mechanism

21‧‧‧ Turntable

3‧‧‧First heating unit

4‧‧‧Pre-blowing mould

40‧‧‧Clamping mechanism

5‧‧‧second heating unit

6‧‧‧Blow molding

60‧‧‧Clamping mechanism

7‧‧‧Conveying unit

71‧‧‧Second transport path

8‧‧‧ finished products

80‧‧‧ preform

81‧‧‧Semi-finished products

91~97‧‧‧Steps

Other features and advantages of the present invention will be apparent from the embodiments of the present invention, wherein: Figure 1 is a schematic view showing a first preferred embodiment of the blow molding apparatus of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 3 is a schematic view showing a three-shot housing of a third preferred embodiment of the present invention; and FIG. 4 is a flow chart illustrating the present invention; Invented a blow molding method.

Before the present invention is described in detail, it should be noted in the following In the description, similar elements are denoted by the same reference numerals.

Referring to Figure 1, a first preferred embodiment of the blow molding apparatus of the present invention comprises a plastic injection unit 1, a preform injection mold 2, a delivery unit 7, a first heating unit 3, and a pre-blowing mold 4. A second heating unit 5 and a blow molding die 6.

The plastic injection unit 1 includes an injection base 11 for projecting plastic, and is used to form a single-layer preform 80. The plastic injection unit 1 is a prior art and will not be described herein.

The preform injection mold 2 is mounted in a mold clamping mechanism 20 having a rotatable and circular turntable 21, the preform injection mold 2 comprising two mutually opposing cores and cavities (Fig. Not shown, and a gate (not shown) respectively communicating with the cavity, the shape of the preform is defined by the core and the cavity, and the gate is provided for the plastic of the injection seat 11. One or more single-layer preforms 80 are injection molded and formed, and the preform injection mold 2 is prior art and will not be described herein. After the mold is opened, the preforms 80 are rotationally moved to the opposite direction by the turntable 21 of the mold clamping mechanism 20.

The transport unit 7 includes a first transport path (not shown) that is continuously operated and a second transport path 71 that is coupled to the first transport path. In the first preferred embodiment, the first transport path is Formed by the continuous rotation of the turntable 21 of the clamping mechanism 20, and the second conveying path 71 is a closed rectangular operation, the second conveying path 71 is adjacent to the rotating plate 21, so that the preforms 80 can be smoothly The first conveying path is conveyed to the second conveying path 71. The first heating unit 3, the pre-blowing mold 4, the second heating unit 5, and the blow molding die 6 are respectively disposed in the second On the transport path 71.

The first heating unit 3 is disposed between the clamping mechanism 20 and the pre-blowing mold 4, and heats each preform 80 on the second conveying path 71. In the first preferred embodiment, the first heating unit 3 The first heating unit 3 is a heating tube, but the first heating unit 3 can also be a heating tube or a heater.

The pre-blowing die 4 is mounted in a clamping mechanism 40, and the pre-blowing die 4 includes two mutually opposing modules (not shown), and a pre-blowing cavity defined by the modules (not shown). And a hole (not shown) respectively communicating with the pre-blowing cavity. Each preform 80 is conveyed via the second conveying path 71 into a pre-blowing cavity of the pre-blowing die 4, and each preform 80 is pre-blowing into a half finished product 81 by the opening. After the mold is opened, each of the semi-finished products 81 is continuously conveyed by the second conveyance path 71.

The second heating unit 5 is disposed between the clamping mechanism 40 and the blow molding die 6 and heats each semi-finished product 81 on the second conveying path 71. In the first preferred embodiment, the second The heating unit 5 is a heating tube, but the second heating unit 5 can also be a heating tube or a heater.

The blow molding die 6 is mounted in a clamping mechanism 60, and the blow molding die 6 includes two mutually opposing modules (not shown), and a forming cavity surrounded by the modules (Fig. And a channel (not shown) respectively communicating with the forming cavity. Each half of the finished product 81 is conveyed into the forming cavity of the blow molding die 6 via the second conveying path 71, and each semi-finished product 81 is blown into a finished product 8 by the hole, and the blow molding die 6 is The prior art is not described here. After the mold is opened, each finished product 8 is discharged through the second conveying path 71.

A second preferred embodiment of the blow molding apparatus of the present invention comprises a plastic injection unit 1, a delivery unit 7, a preform injection mold 2, a first heating unit 3, a pre-blowing mold 4, and a second The heating unit 5, and a blow molding die 6.

The second preferred embodiment is substantially the same as the first preferred embodiment. The main difference is that, referring to FIG. 2, the plastic injection unit 1 of the second preferred embodiment includes two injection housings 11 respectively for supplying plastic. 12, and used to form a double layer of preforms 80. The ejection mounts 11 and 12 are disposed at an angle close to the turntable 21 of the clamping mechanism 20, and after the preform injection mold 2 is aligned with one of the injection mounts 11 and the first layer of plastic is injection molded, the turntable 21 is counterclockwise. After rotating and driving the preform injection mold 2 to another injection seat 12, a second layer of plastic is injected to form a double-layer preform 80, and the turntable 21 is rotated counterclockwise and drives the preform 80 to rotate to another After a position, it is discharged into the second conveying path 71 (see Fig. 1).

A third preferred embodiment of the blow molding apparatus of the present invention comprises a plastic injection unit 1, a delivery unit 7, a preform injection mold 2, a first heating unit 3, a pre-blowing mold 4, and a second The heating unit 5, and a blow molding die 6.

The third preferred embodiment is substantially the same as the first preferred embodiment. The main difference is that, referring to FIG. 3, the plastic injection unit 1 of the third preferred embodiment includes three injection housings 11 respectively for supplying plastic. 12, 13, and used to form a three-layer preform 80. The injection seats 11, 12, 13 are vertically intersected And adjacent to the turntable 21 of the clamping mechanism 20, and after the preform injection mold 2 is aligned with one of the injection mounts 11 and the first layer of plastic is injected, the turntable 21 rotates counterclockwise and drives the preform injection mold 2 to rotate. To the other injection base 12, a second layer of plastic is injected; finally, the turntable 21 is rotated counterclockwise again to drive the preform injection mold 2 to rotate to another injection seat 13, and a third layer of plastic is injection molded to form three layers. The preform 80 is rotated counterclockwise and the preform 80 is rotated to another position and discharged into the second conveying path 71 (see Fig. 1).

Referring to Figure 4, the blow molding method of the present invention comprises the following steps and is described in connection with a first preferred embodiment of the blow molding apparatus of the present invention.

Step 91: setting a first conveying path for continuous operation and a second conveying path for engaging with the first conveying path. Preferably, the first conveying path is formed by rotation of the turntable, and the second conveying path is A closed rectangle that runs in a loop.

Step 92: Using plastic injection unit and preform injection mold, plastic injection molding on the first conveying path and forming at least one preform, and the preform is a single layer preform.

Step 93: The preform after demolding still has a residual temperature, and the preform is transferred to the second conveying path by using a turntable. When the preform passes through the first heating unit, the first heating unit heats the preform.

Step 94: The heated preform is transported into the pre-blowing mold via the second conveying path and pre-blowing into half of the finished product.

Step 95: The semi-finished product after demolding still has residual temperature and When the second heating unit passes, the second heating unit heats the semi-finished product.

Step 96: transporting the heated semi-finished product into the blow molding die via the second conveying path and blow molding into a finished product having a handle, wherein the handle can be formed without any handle Finished products, such as plastic bottles, PET bottles, water bottles and other plastic containers.

Step 97: The finished product after demolding is discharged one by one with the conveying unit, that is, the work is completed.

As described above, when the preform 80 has a residual temperature, the heating is continued by the first heating unit 3, whereby the heating time and the power consumption can be reduced, and the temperature of the preform 80 can be easily controlled, and the pre-blowing can be utilized. After the mold 4 is pre-blowed into the semi-finished product 81, it is blown into the finished product 8, and the preforms 80 are stretched in two stages to reduce the thickness unevenness caused by over-stretching the preforms 80 at a time. The problem is therefore that the yield of the finished product can be improved, so that the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

1‧‧‧Plastic injection unit

11‧‧‧ shots

2‧‧‧ preform injection mold

20‧‧‧Clamping mechanism

21‧‧‧ Turntable

3‧‧‧First heating unit

4‧‧‧Pre-blowing mould

40‧‧‧Clamping mechanism

5‧‧‧second heating unit

6‧‧‧Blow molding

60‧‧‧Clamping mechanism

7‧‧‧Conveying unit

71‧‧‧Second transport path

8‧‧‧ finished products

80‧‧‧ preform

81‧‧‧Semi-finished products

Claims (10)

A blow molding method comprising the following steps: Step 1: setting a first conveying path for continuous operation and a second conveying path for engaging the first conveying path; Step 2: projecting plastic on the first conveying path and Injection molding to form at least one preform; step 3: heating the preform after transferring the preform from the first conveying path to the second conveying path; and step 4: utilizing a pre-blowing on the second conveying path The mold pre-blowing the preform into half of the finished product; Step 5: transporting the semi-finished product on the second transport path and heating the semi-finished product; and Step 6: utilizing a blow molding mold located on the second transport path The semi-finished product is blow molded into a finished product. The blow molding method of claim 1, wherein the finished product of step 6 comprises a handle. The blow molding method according to claim 1, wherein the preform of the step 2 is a double-layer preform. The blow molding method according to claim 1, wherein the preform of the step 2 is a three-layer preform. A blow molding device according to claim 1, comprising: a conveying unit comprising a first conveying path for continuous operation and a second conveying path for engaging the first conveying path; a preform injection mold, The preform injection mold is set at the first input And a first heating unit, the first heating unit is disposed on the second conveying path, and is heated by the preform; a pre-blowing mold is disposed on the feeding path a second conveying path for pre-blowing the preform into a half finished product; a second heating unit disposed on the second conveying path and heating the semi-finished product; and a blow molding die The blow molding die is disposed on the second conveying path and is used to blow the semi-finished product into a finished product. The blow molding apparatus of claim 5, wherein the second conveying path is a closed path. The blow molding apparatus according to claim 5, further comprising a plastic injection unit for projecting the plastic and forming the preform in cooperation with the preform injection mold. The blow molding apparatus of claim 7, wherein the plastic injection unit comprises a plastic injection housing, and the preform is a single layer preform. The blow molding apparatus according to claim 7, wherein the plastic injection unit comprises two injection bases respectively ejecting plastic, and the preform is a double-layer preform. The blow molding apparatus according to claim 7, wherein the plastic injection unit comprises three injection bases respectively ejecting plastic, and the preform is a three-layer preform.