DE3044928A1 - "METHOD AND DEVICE FOR TEMPERING TUBE BLOW PARTS" - Google Patents

Description

TER MEER · MÜLLER ■ STEINMEISTER ^K * ÄOki

DESCRIPTION

The invention relates to a method and a device for heating the neck area of a preform during stretching and blow molding according to the preamble of the main claim and the first device claim.

The invention relates to a method and a device for heating the neck area of a preform, which is first made as an injection molded part from synthetic resin and then into a hollow container, such as such as a bottle, is molded by stretching and blow molding after setting a suitable temperature.

When bottles or other hollow objects by stretching and bubbles are produced, there is a disadvantage that an annular constriction in a boundary region between the neck and the body of the molded part depending on the shape and wall thickness of the neck of the molded part Product is created. This annular constriction results due to a temperature difference between the neck area, which is shaped and held in place by a neck shape and the body of the article subject to reheating by a temperature adjusting device is subject to, as well as in that the area of the object, that is in contact with the end of the neck shape »not sufficiently stretched

For a more detailed explanation, reference should already be made here to FIG. Figure 1a "t shows an upper portion of a preform 1 _r the upper portion nor is mally held by a neck mold 2 which is opened to the left and right ^ The preform X is transferred together with the neck mold Z in a temperature setting or a temperature, and Body Ib'des preform is in this facility

130036/0502

TER MEER · MÜLLER · STEINMEISTER ^K * ^Aoki

introduced for secondary heating. The tempered part is then stretched in the blow mold and inflated to form a hollow molded part 3, such as a bottle,
5

In this case, an annular constriction A according to FIG. 1 (II) is formed in an area which directly adjoins the lower opening of the neck shape 2. There is no such constriction in other areas. It is obvious that a constriction of the type mentioned is unfavorable in the interest of a uniform wall thickness distribution and the avoidance of predetermined break points.

The invention is directed to creating a method and a device of the generic type which it allow the formation of constrictions of the specified type to be excluded or at least reduced,

The invention results in detail from the characterizing part of the main claim and the first device demanding.

In connection with the invention is the temperature distribution has been measured in the trunk 1b after the temperature adjustment, and it has been found that in an area above about 1.5mm below the lower surface (l (! j · Il.il «form 2 a rapid temperature drop], occurs

1 in: el 11 «stretching and blow molding is unfavorable. It is to- : "iii-iinii.mi that this temperature drop on the effect of the ! faliiiurm 2 is based. The temperature near the neck shape 2 is reduced in the direction of this neck shape due to the existing temperature difference, so that an arcuate limited area B according to FIG. 1 (I) of about 1.5 mm including a partial area that results from the neck shape

2 protrudes downwards, in which the temperature is impermissibly

130036/0582 BATH ORIGINAL

TER MEER · MÜLLER · STEINMEISTER ^{K # Aoki}

For the reasons mentioned above, attempts have been made to apply a heat insulating material to the periphery of the lower opening the neck shape and to prevent impermissible cooling in this area before stretching and blow molding. This made it possible to suppress the formation of an annular constriction A, but a destroyed one resulted Area on the contact surface with the heat-insulating material due to poor cooling.

The invention offers the possibility, on the one hand, the formation of annular constrictions A and, on the other hand, the To avoid the formation of damaged areas of the type mentioned due to overheating.

According to the invention, the lower region has a neck shape heated to a predetermined temperature by contact with a heating body, so that a heat transfer from the neck of a Preform that is in contact with the neck mold, on the neck shape around the lower opening and thus the formation of an annular constriction tion when stretching and blowing is prevented. Due to the only partial temporary warming of the neck shapes the molded part can be cooled well after stretching and blowing, so that the molded part is also damaged on the surface of the neck due to overheating is avoided.

According to the invention, a radiator is connected to a temperature control unit. Direction provided for the preform through which the Halü of the preform is heated according to the temperature setting of the preform. The invention has the further The advantage that it can be used in connection with already existing injection blow molding systems, since they only a minor change, namely the installation of the

130036/0582

TER MEER - MÜLLER · STEINMEISTER

^K

- 6 radiators in the temperature control device, required.

In the following, preferred exemplary embodiments of the invention are explained in more detail with reference to the accompanying drawings.

Fig. 1 (1) is a longitudinal section through the neck area a preform and a neck shape for explaining the formation of a constriction during stretching and

Blow;

Fig. 2 (11) shows a longitudinal section through the

Neck portion of a molded bottle; 15th

Figure 2 is a longitudinal section through the neck

a fitting and a neck shape using the invention;

Fig. 3 shows another embodiment of the

Invention relating to the lower end region of the neck shape;

Fig. 4 is a partially cutaway view of the lower end of the neck shape

and a heater above a heating chamber connected to the lower The area of the neck shape is in contact,

In the following, reference should be made to FIGS. 2 to 4. Reference numeral 11 denotes a preform and 12 a neck shape. The neck 11a of the preform forms the top of a hollow molded article and is held in close contact with the neck mold 12, as is the case in a similar manner in the prior art

130036/0582

TER MEER · MÜLLER. STEINMEISTER

^K

is. The body 11b of the preform protrudes from the lower surface of the neck mold.

A heating ring is located on the circumference of the lower opening of the neck shape 12 14 formed from metal, which is covered by a thin layer 13 of heat insulating material, for example heat-insulating paper rests against the rest of the neck shape and in a suitable manner, for example with the help of screw ben 15 is attached to the neck shape. The heating ring 14 has the desired height, and the neck 11a of the preform 11 is through the inner surface of the heating ring 14 and the Neck shape 12 shaped.

The layer 13 of heat-insulating material can, if necessary, omitted. This is because the heat insulating

Material is provided to prevent heating of the entire neck shape during repeated heating the insulating layer 13 does not take part in the treatment or heating of the neck region 11a. 20th

The neck shape 12 is always partially heated, and when this heating spreads over the entire neck shape, becomes the supplied heat is absorbed by the neck shape and associated brackets and guides so that the heat is always removed from the heating ring and does not remain there.

The heating ring 14 consists of a metal that has better thermal conductivity than the metal from which the IUtIa • i F (JJ in 12 is made, and the heating ring 14 can be used directly with i1t; r HaIsform be connected as shown in Fig. 3 iti!

Therefore, before the neck mold 12 is transferred to a blow mold, a heating device with the heating ring 14 in 5 brought into contact, and the circumference of a lower opening the neck mold 12 is at a suitable temperature by

1 3 0 0 3 6/0 S 8 2 ^ ^OF

TER MEER · MÜLLER. STEINMEISTER '°

the heating ring 14 held so that it is prevented that in an area adjacent to the lower surface, the neck mold 12 is too cold.

The heating of the heating ring 14 is preferably carried out with the aid of the heating device with the aid of a temperature control device made, in which the body 11b of the preform 11 a subjected to secondary heating and brought to a temperature suitable for stretching and blow molding,

4 shows a device for controlling the temperature of the preform with heating elements 16 and heat-insulating parts 17, which are alternately stacked and a cavity 18 form for receiving the preform. A frame 19 made of iron is located above the upper heating element 16 and is attached to supports 20, for example with the aid of unspecified screws. A radiator 21 is Mounted vertically displaceably on the temperature control device and supported with the aid of springs 23. The feathers 23 are located in the example shown in unspecified recesses on the upper surface of the Frame 19, are screwed into the bolts 22, which are surrounded by the springs. The springs 23 thus press the Radiator 21 with respect to the frame 19 upwards. At the upper end of the bolts 22 are screw heads that limit the movement of the radiator 21 upwards. The upper surface of the radiator 21 comes on impact of the neck molds 12 in contact with the heating ring 14, The ! ■ Or 23 ensure a firm contact between the heating ring

· ■ "14 and the radiator 21 without an exact spatial Assignment is necessary. A heater 24 is inserted into the radiator 21, which is located in the outer circumferential area of the radiator 21 is located and the temperature is adjustable. When the lower surface of the neck mold 12 together with the heating ring 14 and the preform 11 moved downwards and the heating ring 14 on the heating element 21

130036/0582 ^{BÄD 0RIGINAL}

TER SEA. MÜLLER STEINMEISTER ^{K | Aoki}

meets, the neck portion 11a of the preform is partially in contact with the inner surface of the heating ring 14 is heated in the peripheral area of the lower opening of the neck shape 12, while at the same time the rest of the body 11b of the Preform is tempered in the heating chamber formed by the cavity 18 and the heating elements 16.

130036/0582

Claims (5)

TER MEER-MÜLLER-STEINMEISTER Representatives admitted to the European Patent Office - Professional Representatives befor · the European Patent Office Mandatalres agrees pres! 'Office europeen des brevets Dipl.-Chem. Dr. N, tar Meer Dipl.-lng. H. Steinmeister DipUng, F.E. Müller Siekerwall 7, Triftstrasse 4, D-8000 MUNICH 22 D-48OO BIELEFELD 1 A 558 G
St / ri 2 Nov. 8, 1980 KATASHI AOKI 6037 Ohazaminamijo, Sakakimachi, Hianishina-gun, Nagano-ken, Japan METHOD AND DEVICE FOR TEMPERATURE CONTROL OF INJECTION BLOWDER PARTS PRIORITY: November 30, 1979, Japan, No, 54-155957 PATENT CLAIMS (1.] Process for temperature control of injection-molded parts synthetic resin before stretching and blowing, the neck area of which is held by a neck shape and the torso is subjected to tempering prior to stretching and blowing, characterized in that the preform is heated in the transition area between the lower end of the neck mold and the body of the preform. 2. Device for performing the method according to claim 1, with a neck shape for receiving the upper end region of preforms as well as a heating chamber for 130036/0582 TER SEA. MÜLLER. STEINMEISTER ^K take the preforms held by neck molds and for heating the trunk area of these preforms, characterized by an additional heating device (14,21,24) for heating an annular lower end region of the neck molds (12), the lower opening thereof surrounds 3. Apparatus according to claim 2, characterized in that a metal heating ring (14) whose heat Moleconductivity is higher than the thermal conductivity of the material of the neck shape (12) to heat the neck area (11a) of the preforms (11) in the lower part, the opening of the Neck shapes (12) surrounding area is provided, which Heating ring (14) when lowering the neck molds over a heating chamber (16, 18) with a heated heating element (21) in Touch occurs, 4. Apparatus according to claim 3, characterized in that the radiator (21) on one of the heating Chamber forming heating device (18,16,19) is attached. 5. Apparatus according to claim 4, characterized in that the heating element (21) on the heating device (18,16,19) is elastically supported, 130036/058?