JPH081849Y2 - Blow molding blower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a blow molding blower used for manufacturing a plastic hollow container for storing foods, cosmetics, chemicals and the like by blow molding. .

[Prior Art] A container for foods, cosmetics, medicines, etc., which is a hollow plastic container having a tubular mouth portion integrally extended to one end of a body portion, is not limited to this example. Known from the past.

[Problems to be Solved by the Invention] By the way, in a plastic hollow container in which a tubular mouth portion is integrally extended at one end of a body portion, a horizontal flange portion is provided at the mouth portion. In addition, a rising portion that protrudes upward from the flange portion is formed.
In order to blow mold such a mouth portion having a rising portion, it is sufficient to form a recess in the member forming the mouth portion and allow the resin of the mouth portion to flow into the recess during blow molding. Since air is accumulated in the concave portion of the forming member, the flow of the resin is blocked by the air in the process of flowing the resin,
The resin does not flow into the entire concave portion, and as a result, the shape of the rising portion of the mouth portion is not constant and the wall thickness is not uniform.

SUMMARY OF THE INVENTION The present invention is intended to eliminate the above-described inconvenience, and the blow nozzle or the mouth portion forming ring has a ventilation passage communicating from the concave portion for forming the rising portion to the outside. When the resin is pressed into the recess during molding, the air that has accumulated in the recess is released to the outside through the ventilation path, eliminating the obstruction of the resin flow due to the compression pressure of air, and the resin flows into the entire recess. Thus, it is an object of the present invention to provide a blow molding blowing device capable of forming a rising portion having a constant shape and a uniform wall thickness at the mouth.

[Means for Solving the Problems] The present invention is configured as follows as technical means for achieving the above object.

That is, the structure is such that a blow nozzle that blows pressurized fluid into the parison arranged between the split molds to regulate the inner diameter of the mouth portion, and a mouth portion forming ring fitted to the blow nozzle. In a blow molding blow apparatus for a hollow container having a mouth portion having a horizontally formed flange portion and a rising portion protruding upward from the flange portion, the blow nozzle or the mouth portion forming ring is The blow molding blowing device is characterized in that it has a concave portion forming a rising portion of the mouth portion, and a ventilation passage for allowing air in the concave portion to escape to the outside.

[Operation] When a blow molding device according to the present invention is used to blow mold a hollow container, molten resin flows into the blow nozzle or the recess of the mouth forming ring in the process of forming the mouth, and the mouth rises. However, since the blow nozzle or the mouth portion forming ring has a ventilation path leading from the recess to the outside, the air accumulated in the recess while the pressurized molten resin flows into the recess is formed. The resin can be sequentially released to the outside through the ventilation path by the inflow pressure of the resin, and the resin flowing into the recess is not subjected to an excessive pressure due to the compression of air, and the resin completely flows into the recess. As a result, a rising portion having a constant shape and a uniform wall thickness is formed at the mouth.

Embodiment An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numerals 1 and 1 denote split molds for blow molding a hollow container. A parison is arranged between the split molds 1 and 1, and a hollow container 2 is blow molded. In this blow molding process, from the upper part of the split mold 1,1 into the parison,
A blow-in device constituted by a blow-in nozzle 4 that regulates the inner diameter of the mouth portion 3 of the hollow container 2 and blows a pressurized fluid, and a mouth-portion forming ring 5 that is fitted in the blow-in nozzle 4 is driven in, The pressurized fluid is blown into the parison from the conducting portion 6 of the blowing nozzle 4.

The mouth portion forming ring 5 fitted in the blow nozzle 4 is
The flange portion 7 and the rising portion 8 of the mouth portion 3 are formed, and a recess 9 that forms the rising portion 8 is formed inside thereof. The part from the bottom surface of the recess 9 to the top surface of the mouth forming ring 5 is made of sintered metal.
The ventilation passage 10 is further communicated to the outside by a plurality of radial holes 11. The sintered metal forming the ventilation path 10 has a large number of small holes and is breathable. The blow nozzle 4 is formed in a taper shape having a reduced diameter in the front end direction, and the mouth forming ring 5 is formed so as to be closely fitted to a predetermined portion of the blow nozzle 4. The mouth portion forming ring 5 can be inserted and removed from the tip end side of the tapered blowing nozzle 4 and replaced.

When blow molding is performed by the apparatus having the configuration shown in FIG. 1, as shown in FIG. 2, the mouth portion 3 is extended to the upper end of the body portion 12, and the flange portion 7 is provided on the mouth portion 3. And the hollow container 2 in which the rising portion 8 is formed is obtained.

By the way, in the blow molding process shown in FIG.
The molten resin also flows into the recess 9 of the mouth portion forming ring 5 under pressure, but the bottom surface of the recess 9 is made of a sintered metal.
Since it is communicated to the outside through the 10 and the plurality of radial holes 11, the air accumulated in the recess 9 in the process of the resin flowing into the recess 9 escapes from the ventilation passage 10 and the plurality of holes 11 to the outside. Compressed air pressure is not applied to the resin flowing into the concave portion 9, and the resin flows into the entire concave portion 9. Therefore, the rising portion 8 of the mouth portion 3 formed by the concave portion 9 is always formed to have a constant shape and a uniform thickness.

In the apparatus having the configuration shown in FIG. 1, the ventilation passage 10 communicating from the recess 9 to the outside may be a small gap formed between the mouth portion forming ring 5 and the blow nozzle 4, and further, in the recess 9 The air may be sucked and discharged through the ventilation path 10. When the air is discharged from the recess 9 by suction, the resin can be positively introduced into the recess 9, so that the rising portion 8 of the mouth 3 can be formed more favorably.

3 and 4 show another example of that shown in FIG.

In this other example, a step portion 13 is provided on the blowing nozzle 4 of the blowing device.
To form the opening forming ring 5 on the stepped portion 13
And a mouth portion forming ring 5 is elastically biased downward by a spring 15 interposed between the holding pin 14 and the supporting portion of the holding pin 14 of the blowing nozzle 4. . Then, above the concave portion 9 forming the rising portion 8, it communicates with the outside through the ventilation passage 16.

Therefore, according to the device configured as described above, when the blowing device is driven into the parison from the upper part of the split molds 1, 1, the mouth forming ring 5 first biases the spring 15 in the process. Reaching the formation position of the mouth part 3 in the state of being elastically lowered (the third
Fig.), Followed by the mouth forming ring 5 pushed by the blow nozzle 4
Lowers against the spring 15 (Fig. 4). For this reason, the density of the resin in the recess 9 is increased, and the shape and the thickness of the resin are more uniformly formed. The air in the recess 9 is discharged from the passage 16 to the outside.

As in this embodiment, the blow-in nozzle 4 is driven in two steps, so that the recess 9 in the state shown in FIG.
It is possible to reduce the compressed air pressure in the inside, and therefore, as in the previous embodiment, without using a ventilation path made of sintered metal,
This rising portion can be formed in a state in which the compressed air pressure is not applied in the concave portion only by the air passage formed by the contact surface between the mouth portion forming ring 5 and the blowing nozzle 4.

In each of the above embodiments, the concave portion 9 is formed in the mouth portion forming ring 5, but it may be formed in the blowing nozzle, or may be formed in both the mouth portion forming ring and the blowing nozzle.

[Effect of the Invention] The present invention is to form a mouthpiece which is driven into a parison disposed between split molds to regulate the inner diameter of the mouth portion and blows a pressurized fluid, and a mouth portion which is fitted into the nozzle. In a blow molding blow device for a hollow container having a mouth portion having a horizontally formed flange portion and a rising portion protruding upward from the flange portion, the blow nozzle or the mouth portion is formed. Since the ring has a concave portion that forms the rising portion of the mouth and an air passage for letting the air inside the concave portion escape to the outside, during the process of press-fitting the resin into the concave portion during blow molding, , The air accumulated in the recess is released to the outside through the ventilation passage so that compressed air is not added to the recess, obstructing the flow of resin due to the compression pressure of air, and the resin flows into the entire recess. To do As a result, a blow molding blowing device can be obtained in which a rising portion having a constant shape and a uniform wall thickness can be formed at the mouth.

[Brief description of drawings]

1 is a longitudinal sectional front view of a part of an apparatus showing an embodiment of the present invention, FIG. 2 is a perspective view of a part of a hollow container blow-molded by the apparatus of FIG. 1, FIG. 3 and FIG. The drawing is a vertical sectional front view of a part of an apparatus showing another embodiment. 1,1 ...... divided dies, 2 ...... hollow container, 3 ...... mouth, 4 ...
... Blowing nozzle, 5 ... Port forming ring, 7 ... Flange, 8 ... Rise, 9 ... Recess, 10 ... Ventilation path, 11 ...
… Multiple radial holes, 12 …… Body, 14 …… Holding pin, 15…
… Spring, 16… Ventilation path

Claims (1)

[Scope of utility model registration request] 1. A blowing nozzle configured to be driven into a parison disposed between split molds to regulate an inner diameter of a mouth and blow a pressurized fluid, and a mouth forming ring fitted to the blow nozzle. In the blow molding blow device for a hollow container having a mouth portion having a horizontally formed flange portion and a rising portion protruding upward from the flange portion, the blow nozzle or the mouth portion forming ring, A blow molding blowing device comprising: a concave portion forming a rising portion of a mouth portion; and a ventilation path for allowing air in the concave portion to escape to the outside.