DE1812797A1 - Method and device for the production of hollow bodies by blow molding - Google Patents

Description

Attachment to the patent application

Sel / Ha of November 29, 1968.

Method and device for the production of hollow bodies by blow molding

The invention relates to a device and a method for producing plastic containers and hollow plastic objects in a blow molding process, a tubular blank being introduced into a multiply divided mold and the tubular blank being separated and expanded to its final shape with the aid of a blowing device. The ^u bott om mold parts are arranged to be movable in the transverse direction.

From the German patent application P 3153 VII / 39a is already since many years a method for the production of hollow bodies from organic, thermoplastic plastics, which are inflatable by pressure medium, known. Following this procedure, the plasticized plastic to a hollow body closed at the end preformed. Then inflation and solidification take place within the form. According to the German patent specification 971 333 thermoplastic mass in the extrusion process to a tube-like hollow body preformed and this intermediate product in the

_{o in a} warm state via the mouthpiece of a blower nozzle. Thereafter

takes place in a hollow mold designed as a squeeze mold, the

¹ ^ blow to the hollow body. The hitherto after these devices resp.

^ Process produced, especially large-scale hollow bodies ο show mainly on the floors and aiii transition from floor to coat Wall thinning, so that in the places exposed to greater stress by putting on, shaking and the like. Are subjected to easier

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Damage can occur.

According to German utility model 1 857 242, the use of a device was therefore already proposed for the production of large-volume hollow bodies in which a movable bottom molding is present separate from the mold, which receives the plasticizable plastic blank after it has been squeezed off. This vertical up and down movable floor molding is lowered in a further step so that the molding rests on the hollow floor . This process is carried out in such a way that the hose walls can not touch and welding or sticking of the wall is avoided. However, the blank must be closed by means of a pincer-like lever device, the lever of which, when pressed, compresses the open end of the hose and thereby welds it together. This device thus requires a precisely working, adjustable pincer-like lever device and its constant checking. Furthermore, this device requires that the separately working bottom part receives the blank in such a way that it does not overlap laterally on the still moving bottom part, since otherwise the material will be squeezed off and damaged when the mold is closed

can. Finally, the movable bottom part must be accurate on the one hand fit into the shape and be firmly closed with it, on the other hand

i must be able to separate in the next step « These functions require a very precise setting of the shape and significant maintenance and control of the entire device,

The aim and task of the present- Erfiudipig, was- it. therefore,

also with that. Blowing process- material occurring near the ground «·"!

Avoid dilution and dapflBai? htaams n & oh possibility- a-el · '''"*

■ Certain material accumulation on the heavily used container bottom. share including transition zones to reach. A further aim of the present invention was to set up a person who works as simply as possible, which is easy to check and control. Device “Ultimately, the aim was to eliminate the need for an additional pincer-like lever for closing and connecting the end of the hose. Furthermore, it should also be possible to use hollow bodies with undercut or strongly recessed

produce stogenem bottoms that can be demolded without damage »Another aim of the invention was the production of hollow bodies which are also suitable for receiving pressurized liquids and which also have a certain stability even when filled with pressurized products ensure a longer period of time.

- * "'-. ■' ■■■ '■
ι According to the invention, it was found that these assigned tasks are easily solved by using an apparatus and method for the production of plastic articles by blow ■■ * "SEN> ■■! if you want a 3" comparable preferably 4 or multi-part form J) * turns at least two molded parts across or at an angle of; Approx. 90 sum of the blank are movably arranged, which squeeze the hose when they interlock or press against one another and support the pinched end of the hose. The bottom parts of the total 3- »preferably 4- or multi-part shape are thus formed at least in two parts as a squeeze shape according to the invention and additionally arranged to be movable transversely to the emerging arts fabric blank. In the multi-part bottom mold, elevations are added approximately perpendicular to the mold parting plane, which lead to depressions in the bottom edge of the prefabricated part. The combined working range is particularly advantageous both in the transverse direction and

• additionally in the direction or opposite direction of the exiting Hose movable floor parts. By means of this device, a plastic hanging between the molded parts is first achieved Hose squeezed off at the lower end by means of the molded bottom parts. The molded parts for the container body then also close around the hose. The tube is cut off in the usual way above the mold. Then the bottom part of the mold is raised » As a result, the hose is compressed in the mold near the floor, which in the subsequent inflation process leads to an accumulation of material ' ι leads to the bottom of the container including transition zones.

According to a particularly advantageous embodiment, a two-part Bottom or squeeze shape used, which, in addition to the bottom, also includes part of the vessel or hollow body membrane with »Particularly The use of an at least two-part bottom form has proven expedient in combination with a two-part vessel jacket or hollow body shape. The bottom and vessel shell shapes can also be three or more parts. Ee is not absolutely necessary; that the Gefäßmante'lform consists of the same partial number as the bottom or, squeeze shape; however, it has proven to be useful the same partial numbers of the bottom or squeeze shape with the vessel shell or to combine hollow body shape. An additional accumulation of material near the ground can also be achieved by

that after the hose is squeezed off, the formo closes

ο halve and the separation of the hose is delayed and the to

U opened plastic tube runs up close to the ground before the cycle ^ continues. (Picture 5 of the drawing). ,

—3 ■ ■ '-

"" * Scrr.it are the shell molded parts only then closed and the 10..Is-UaI ", = ivzz i & nn exr ^ tro-nnt, when the tube is one for the hollow

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body has exceeded the required length. It continued to prove as particularly expedient to arrange or design the bottom molding so that it can be folded down or lowered so that deeper undercuts at the bottom of the hollow body and a damage-free removal of the hollow body from the mold are made possible.

An exemplary embodiment is described schematically in the accompanying drawing. The shape used in the example consists of four parts (see Fig. 1). The warm plastic mass emerges from the extruder nozzle (1) in the form of the plastic hose (2). The tube (2) hangs between the mold halves and is _{squeezed or welded on the bottom (} or squeeze mold (3)) at the lower end, as shown in Figure 2. Then the vessel jacket or hollow body shapes (4) close around the tube The tube is finally cut above the mold by a cutting knife etc. (5) The subsequent lifting of the bottom or squeeze shape is shown in Figure 4. This process, which takes place after the squeezing off, leads to a compression of the tube in the mold The movements shown one after the other in Figure 3 and Figure 4 can also be carried out at the same time it is possible to remove containers with deep undercuts on the bottom).

° According to a particularly advantageous embodiment, the two ££ Divide the mold approximately perpendicular to the mold parting plane, with elevations · *. brings them to indentations in the ground, preferably in the bottom edge - "- * lead bead of the plastic part. Through this in the soil form

o ^: ■ ·

~ * share located increases that allows an interruption

the edge bulge, e.g. of the flashlight bottom, is at an angle of approximately 90 °, d. H. it is achieved that especially when under pressure

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standing filled containers (e.g. beer bottles) through the interruption of the bead at the point * where the largest AyBd

_m 9

of the filled vessel takes place, the stability is not impaired} will. . ·

009825/1701

c ORIGINAL INSPECTED

Claims (1)

Claims ι It process and device for the production of plastic containers • \ and iiohlen Kunstetoffartikel by blowing, whereby a. ^ Tubular blank is filled into a divided mold, the tubular blank is separated and expanded with the help of a blowing device for its final shape, characterized in that the squeezing off and welding the tube is carried out by a ih the transverse direction turn Hohling movable multi-part base mold, Bind mounted in üer approximately perpendicular to the mold parting plane increases, resulting in depressions in the Bodenrandwuiit of the finished part, and after the closing of the bottom form an association , the vessel jacket or hollow body shape takes place, the tube above the mold is separated with a separator and the like, then the bottom part of the mold is raised and the blow pin or the like is introduced for the subsequent blowing process. 2 »Method and device for the production of plastic containers and hollow plastic objects in the blow molding process according to claim 1, characterized in that a 3, preferably 4 or multi-part mold is used, in which at least 2 molded parts transversely or at an angle of approximately 90 ° are movably arranged to the blank, which squeeze off the hose when they interlock or press against one another and support the pinched end of the hose. 3. The method and device for the production of plastic containers according to claim 1 and 2, characterized in that the dia at least two-part, formed as a ^ uetschform Bcänenfoiv /. can also be moved in the direction or opposite direction of the exiting hose. 009825/1701 Oiiffm ^: iA ^ röAD ORIGINAL <ί. Method and device for the production of plastic containers according to claims 1-3 *, characterized in that the hose is intended for further stiffening due to its excess length Part of the cabbage body experiences favorable thickening before it is separated. -j. Method and device for producing plastic containers according to claims 1-4, characterized in that the Ilantel molded parts are only closed and the hose is only separated when the hose has exceeded the length required for the hollow body. ι.-. Method and device for the production of plastic containers according to claim 1 - 5 * characterized in that a two, or multi-part bottom or squeeze shape is used which, in addition to the bottom, also includes a part of the vessel or hollow body jacket. , '. Method and device for the production of plastic containers according to claims 1 - 6, characterized in that a two-part bottom or squeeze shape and a two-part vessel jacket or ί: oilIbody shape is used. ^. Method and device for the production of plastic containers according to claims 1-7, dadurca ~ ekannzeiciinct, caü the bottom or ^ uetsc.ifo. ¹ .'.-. .der die Gefä2man-telfrriri in three parts or rr.ehr ^ eili ^ i- '· - DEUTOCHE oC
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