DE737843C

DE737843C - Injection molding machine for thermoformable materials

Info

Publication number: DE737843C
Application number: DEB190212D
Authority: DE
Inventors: Emil Hempel
Original assignee: FRANZ BRAUN AG
Current assignee: FRANZ BRAUN AG
Priority date: 1940-03-20
Filing date: 1940-03-20
Publication date: 1943-07-26

Description

Spritzgußmaschine für wärmeformbare Stoffe Zusatz zum Patent 731 723 Der Gegenstand des Hauptpatents ist eine Spritzgußmaschine zum Verarbeiten wärme formbare Massen, bei welcher die Spritzdüse, die sich nach Beendigung des Spritzvorganges von der Form abhebt, als Abschlußschieber für den Düsenkanal ausgebildet ist. Nach Beendigung des Spritzvorganges wird dieser Abschlußschieber so verstellt, daß seine Düsenmündung durch die untere Wandung der Aussparung des Düsenmundstückes, die den Abschlußschieber aufnimmt, verschlossen wird.Injection molding machine for thermoformable materials. Addition to patent 731 723 The subject of the main patent is an injection molding machine for processing heat malleable masses, in which the spray nozzle, which is after the end of the spraying process stands out from the shape, is designed as a closing slide for the nozzle channel. To Completion of the injection process, this slide valve is adjusted so that its Nozzle orifice through the lower wall of the recess of the nozzle mouthpiece, which the Closing slide receives, is closed.

Zweck dieser Anordnung ist es, zu verhinderen, daß aus der Düse, wenn diese nach Bleendigung des Spritzvorganges von der Form zurückgezogen wird, ein Rest der Spritzmasse austritt und Fäden bildet, die dann abkühlen und erstarren und beim nächsten Spritzvorgang hinderlich sind. The purpose of this arrangement is to prevent the nozzle, if this is withdrawn from the mold after the injection process has ended, a remainder of the spray compound emerges and forms threads, which then cool and solidify and are a hindrance to the next spraying process.

Es müssen dabei Vorkehrungen getroffen werden, um sicherzustellen, daß die im Düsenkanal eingeschlossene Masse plastisch bleibt, während sich die Düse in Absperrstellung befindet. Zu diesem Zweck ist bei dem im Hauptpatent beschriebenen Ausfährungsbeispiel der Abschlußschieher mit einer Heizvorrichtung versehen. Precautions must be taken to ensure that that the mass enclosed in the nozzle channel remains plastic while the nozzle is is in the shut-off position. For this purpose is described in the main patent The final slider is provided with a heating device.

Die vorliegende Erfindung schlägt hierfür eine andere Lösung vor. Die Anordnung wird so getroffen, daß die Bohrung des Abschlußschiebers in ständiger Verbindung mit dem Spritzkanal steht. Es findet daher ein ständiger Wärmeaustausch zwischen der Masse innerhalb der Spritzdüse und der Masse in den Kanälen des Mundstücken statt. The present invention proposes a different solution for this. The arrangement is made so that the bore of the final slide in constant Connection with the spray channel is. There is therefore a constant exchange of heat between the mass inside the spray nozzle and the mass in the channels of the mouthpiece instead of.

Vorzugsweise erweitert sich die Bohrung des Abschlußschiebers nach dem Spritzkanal hin. Preferably, the bore of the closing slide widens towards the spray channel.

In der Zeichnung ist ein bevorzugtes Ausführungsbeispiel der Erfindung veranschaulicht, und. zwar zeigt Fig. I einen Längsschnitt durch das Düsenmundstück und eine zur Form gehörige Buchse, wobei sich der Düsenschieber in Absperrstellung b;efindet, Fig. 2 eine der Fig. 1 entsprechende Darstellung mit geöffneter Düse, Fig. 3 den Schnitt nach der Linie 3-3 der Fig. 2, und Fig. 4 den Düsenschieber für sich allein in Ansicht von oben veranschaulicht.In the drawing is a preferred embodiment of the invention illustrates, and. although Fig. I shows a longitudinal section through the nozzle mouthpiece and a socket belonging to the mold, the nozzle slide being in the shut-off position b; e finds FIG. 2 shows a representation corresponding to FIG. 1 open nozzle, FIG. 3 shows the section along the line 3-3 of FIG. 2, and FIG. 4 shows the Illustrated nozzle slide on its own in a top view.

Claims

As in the main patent, the nozzle valve is a rotary valve 121 formed. It is in a horizontal bore 120 of the nozzle mouthpiece 116 stored. This has a recess below with beveled walls I23, which exposes the nozzle slide 121 from below, so that an approach I24 on the Form can apply to the circumference of the rotary valve I2I.

The approach I24 has the shape of a socket with a conical Edge, which at the same time rests against the wall 123 in a sealing manner.

The spray nozzle is supported by a recess 122 in the rotary valve I2I educated. As Fig. I shows, the lower mouth of the nozzle I22 is in the shut-off position closed by the lower wall 119 of the bore 120. The upper mouth of the According to the invention, nozzle I22 is here with the spray channel 117 of the nozzle mouthpiece in connection.

In the illustrated embodiment, this is made possible by that the conical nozzle channel 122 has a lateral extension a. It becomes through it achieves that the mass located in the nozzle channel 122 with that in the spray channel 117 located hot mass is in constant heat exchange and therefore not so easily stiffens. A special heating device for the gate valve 121 is therefore may be dispensable.

The mode of action corresponds to that described in the main patent. the Nozzle is opened in that a not illustrated, by the dash-dotted line Line I44 indicated arm of the rotary valve 121 pivoted to the position I44 ' will. As a result, the nozzle channel 122 comes into the position of FIG. 2, so that the softened Material from the heating cylinder 13 through the socket I24 into the mold can flow in. After the injection process has ended, the rotary slide valve 121 is again rotated into the position of FIG. When this has happened, the slide moves with socket I24 downwards. In doing so, the mass in the socket is released without residue from the smooth peripheral surface of the rotary valve 121, so that no The thread is pulled out and no residues of the mass remain on the nozzle, that could get cold and hard.

The invention can also be used when the nozzle slide is not rotatable but slidable.

P A T E N T A N S P R U C H: Injection molding machine for thermoformable Substances in which the one that stands out from the mold after the end of the injection molding process Spray nozzle is designed as a slide valve for the nozzle channel, according to patent 73I723, characterized. that also in the final position of the closing slide the inner part of the bore, e.g. B. as a result of an expansion of the bore of the closing slide towards the spray channel, is in connection with the spray channel.