DE19646365A1 - Method and device for transferring moldings - Google Patents

Abstract

The inventive method and device are intended for transferring castings to the area of a blow-forming unit designed to produce thermoplastic containers. A blank is fed to at least one heat producing unit for the purposes of preliminary heating and to at least one blow-forming unit. On at least one section of the path, the blanks are held by a gripping device (33) and the casting (32) positioned by a holding member (23), relative to which a positioning device (24) is fixedly mounted, just as a direction setting device is mounted fixedly relative to the holding member (23). In the case of a relative motion by the gripping member (33) in the direction of the casting (32) to be gripped, the direction setting device (17) is so positioned relative to the positioning member (24) that the gripping member (33) is also positioned relative to the casting (32). The method enables material degradations and rubbing off to be prevented.

Description

The invention relates to a method for transferring Moldings in the area of a device for blow molding of containers made of a thermoplastic material, at which is a preform of at least one heating device for temperature control and at least one blow molding station Blow molding is supplied and in which the moldings along at least part of their route are held by a gripping element.

The invention also relates to a device for the transfer of moldings in the area of a facility device for blow molding containers from a thermo plastic material in which the device for blowing forming a heating device for tempering  Preforms and at least one blowing station for blowing deformation of the preforms and with is provided at least one gripping element which Preforms along at least part of their Transport route within the facility for blowing formation holds.

Such devices are used to preform linge from a thermoplastic material, for example white preforms made of PET (polyethylene terephthalate) Different processing within a blow molding machine supply stations. Typically one such blowing machine a heater and a Blower device in the area of the previously tempe preformed by biaxial orientation to one Container is expanded. The expansion takes place with Using compressed air to expand into the Preform is initiated. The procedural Procedure for such an expansion of the preform is explained in DE-OS 43 40 291. The device can also be used to finish blown Take the container out of the blower.

The basic structure of a blowing station for loading Container shaping is described in DE-OS 42 12 583 and options for tempering the preforms are explained in DE-OS 23 52 926.

Within the blow molding device, the Preforms as well as the blown containers with the help different handling devices transport be animals. The Ver turning of mandrels on which the preforms be plugged on.  

The use of support bodies for handling the Preforms have the advantage that the preform linge with their mouth on a coupling element of the Support body can be plugged in and that during of the further transport movements the Trans used port elements only on the support body and not act directly on the preform. This will Damage and deformation due to warming soft preform avoided. In addition, a Material removal through direct-acting gripping elements, the for example, could lead to dust generation, avoided.

The known support body in the form of transport mandrels have high mechanical strength and thereby requires high reliability and a long time Lifespan. Especially when using rotating transport devices, however, run away forces that affect the handling speed pregnant.

The use of gripping pliers for handling Preforms are used, for example, in the FR-OS 27 20 679. An expanding mandrel that holds Insert into a mouth area of the preform bar is explained in WO 95 33 616.

According to the state of the art, it is not sufficient way possible the properties of a low Weight of the device for handling the moldings, high operational reliability and a gentle hand to combine the shapes.

The object of the present invention is therefore a Device of the type mentioned in the introduction  improve that with a light weight a gentle Handling of the moldings is guaranteed.

This object is achieved in that the molding before the gripping element is accessed by a holding element is positioned relative to the a positioning element is arranged stationary that an alignment element fixed relative to the gripping element is arranged and that with a relative movement of the Gripping element in the direction of the to be gripped Shaped the alignment element relative to the positioning element and thus also the gripping element relative to the Molding is positioned.

Another object of the present invention is a Ver device of the type mentioned in the introduction improve that careful handling of the moldings with a low construction weight of the device is supported.

This object is achieved in that the gripping element rigid with an alignment element ge is coupling that in the area of the molding load-bearing element is a positioning element is arranged and that the alignment element and the gripping element relative to each other so adapted and relative are arranged to each other in such a way that in a rela active movement of the gripping element in the direction of that Holding elements by contact between the alignment ment and the positioning element an alignment of Gripping device is given relative to the molding.

A typical handling process can go through leads that the gripping element from a handover wheel is positioned.  

To facilitate handover of the molding, struck that the gripping element relative to the handover Rad can be positioned in the radial direction.

According to a variant of the method it is provided that Holding element arranged in the area of the blowing station becomes.

It is also possible that the holding element in the loading rich the heater is arranged.

This enables two-dimensional positioning be supported by a tapering Guidance when the alignment element interacts and the positioning element positioning transversely to a direction of movement of the gripping element is led and that by an effective Stop additionally positioning in motion direction of the gripping element takes place.

To provide a smooth adjustment provided that the positioning element roll-like is used.

Alignment is supported by the fact that the straightening element is used like a fork.

According to another embodiment it is provided that the positioning element is used like a fork.

Adapted to this, it is appropriate that the alignment ment is used in a roll-like manner.  

A possible application is that the Form standing with a vertical mouth Is handled in a downward direction.

In particular, the method is also used characterized in that the molding hanging with a mouth in a vertical direction upwards is handled.

According to a typical container forming procedure it is provided that the molding within the blow station after a handover from a high bar rod is stretched in the longitudinal direction.

To perform a biaxial orientation provided that the molding after one Delivery within the blowing station from one below Pressurized medium expands and biaxially orien is tiert.

Exemplary embodiments of the invention are shown in the drawing shown schematically. Show it:

Fig. 1 is a schematic plan view of a Vorrich tung for blow molding of thermoplastic materials,

Fig. 2 is a plan view of an alignment member that is not recognizable at this viewing direction above a gripping element is arranged,

Fig. 3 shows a cross section along section line III-III in Fig. 1 with associated positioning element and

Fig. 4 is a schematic representation to illustrate an arrangement of the alignment element in the region of a molding and the assignment of the alignment element to the gripping element.

In the embodiment shown in FIG. 1, the device for blow molding containers has a heating wheel ( 1 ) and a blowing wheel ( 2 ). Preforms to be processed are fed via a feed rail ( 3 ) into the area of a turning device ( 4 ) and transported by transfer wheels ( 5 , 6 , 7 ) into the area of the heating wheel ( 1 ). In this variant, the preforms are hung with their mouths oriented upwards along the feed rail ( 1 ) and rotated by the turning device ( 4 ) by 180 °. Heating in the area of the heating wheel ( 1 ) takes place in such a way that the preforms are oriented upright with their mouths facing downward. But it is also conceivable to carry out a hanging heater without previous turns of the preforms.

Heating devices ( 8 ) and cooling devices ( 9 ) are arranged along the heating wheel ( 1 ). Preferably, a cooling device ( 9 ) is arranged between two heating devices ( 8 ). The heating devices ( 8 ) heat the preforms with the help of IR radiation and the cooling devices ( 9 ) blow to the surface cooling calls to the surfaces of the heated preforms.

After completion of the heating and passing through a cooling section, the tempered preforms are transported from a transfer wheel ( 10 ) to the blowing wheel ( 2 ) and used here in molds ( 11 ) which are held by blowing stations ( 12 ). The blowing stations ( 12 ) can be opened and closed like a book. After the blowing process has been completed, completely blown containers are removed from the blowing station ( 12 ) and fed to a delivery section ( 15 ) by transfer wheels ( 13 , 6 , 14 ). In a blow molding of the preforms in the area of the blowing wheel ( 2 ) with a muzzle orientation downward, it is particularly intended to arrange a further turning device between the blowing wheel ( 2 ) and the discharge section ( 15 ), so that the blown container is suspended in the area Output route ( 15 ) can be transported.

Fig. 2 shows a plan view of the transfer wheel ( 10 ), which inserts the preforms into the blowing stations ( 12 ) in the area of the heating wheel ( 1 ). In the associated embodiment, it is in particular contemplated to expand the preforms with their mouths oriented upward in the area of the blowing station ( 12 ) to form a finished container. To ensure precise insertion of the preforms into the blowing station ( 12 ), alignment elements ( 17 ) are arranged in the region of transfer arms ( 16 ) of the transfer wheel ( 10 ). The alignment element ( 17 ) has a fork-like centering seat ( 18 ).

The transfer arms ( 16 ) consist of an arm base ( 19 ) rigidly connected to the transfer wheel ( 10 ) and a telescopic arm extension ( 20 ) which, among other things, carries the alignment element ( 17 ). The transfer arms ( 16 ) are pivotally limited relative to an arm axis of rotation ( 21 ) rotatably mounted. Typically, the rotatable bearing is re alized such that there is only a slight play that enables circumferential evasive movements of approximately +/- 1 mm to be carried out in the region of the centering receptacle ( 18 ). A clearance of +/- 0.5 mm is usually sufficient.

In Fig. 2, an assembly aid element ( 22 ) is additionally arranged in the substantially horizontally running transfer wheel ( 10 ), which prevents a relative movement of the arm extension ( 20 ) to the arm base ( 19 ) during assembly. It can also be seen that the centering receptacle ( 18 ) widens in a direction facing away from the arm rotation axis ( 21 ) in order to support a funnel-like threading.

Fig. 3 shows a cross section according to section line III-III in Fig. 2 in dissolved relative to the alignment member (17) mounting auxiliary member (22) and at such a retracted arm extension (20), that the illustration in Fig. 2, the alignment member (17 relative ) approximated to the arm base ( 19 ).

In the embodiment according to FIG. 3, a holding element ( 23 ) is provided for fixing the molding in the area of the blowing wheel ( 2 ). The holding element ( 23 ) is not recognizable in Fig. 3 due to its mounting position. One of the holding element ( 23 ) fixedly assigned positioning element ( 24 ) is used to align the alignment element ( 17 ) with a relative approach. In the FIG. 2 embodiment of the fork-like Ausrichtele mentes (17) the positioning element (24) may be example be designed as a roller (25). The roller ( 25 ) can, for example, be formed as a rotatable sleeve which is rotatably supported by a stretching rod guide ( 26 ). The stretching rod guide ( 26 ) is used to guide a stretching rod ( 27 ) and to lead it through a connecting piston ( 28 ) to the compressed air line in the area of the molding.

To enable compressed air to be supplied to the molding, the connecting piston ( 28 ) has an air supply ( 30 ) and various seals ( 29 ). Inside the connecting piston ( 28 ), the compressed air is passed through an annular gap ( 31 ) surrounding the stretching rod ( 27 ).

FIG. 4 shows the assignment of the components according to FIG. 3 in another image detail, which in particular also clarifies the mounting of the molded part ( 32 ). In the processing state shown, the molding ( 32 ) is designed as a preform, which has already been tempered for subsequent biaxial orientation, but which has not yet been subjected to compressed air.

The molding ( 32 ) is held above the blowing station ( 12 ) by a gripping device ( 33 ) which is arranged in a stationary manner relative to the alignment element ( 17 ). The gripping device ( 33 ) is thus positioned by the transfer arm ( 16 ) together with the alignment element ( 17 ).

For height positioning, the connecting piston ( 28 ) is provided with a guide roller ( 34 ) which can be positioned by an assigned cam control.

The alignment process and thus indexing is carried out in such a way that when the gripping device ( 33 ) moves together with the molding ( 32 ) in the direction of the holding element ( 23 ) through the positioning element ( 24 ), the alignment element ( 17 ) is aligned . Due to the fixed assignment of the alignment element ( 17 ) to the gripping device ( 33 ) and the positioning element ( 24 ) to the holding element ( 23 ), the preform is transferred to the holding element ( 23 ) in a precisely defined manner. An analogous process follows after inflating and orienting the preform to the finished container, which is removed from the blowing station ( 12 ) by a comparable gripping device ( 33 ). Here, too, an exact positioning of the gripping device ( 33 ) relative to the molding ( 32 ) is ensured, so that rubbing or grinding of gripping jaws of the gripping device ( 33 ) on the material of the molding ( 32 ) can be avoided.

The combination of the gripping device ( 33 ), the straightening element ( 17 ), the holding element ( 23 ) and the positioning element ( 24 ) can be used in modified forms from any position of the blow molding machine, at the transfers of the molding ( 32 ) it follows . In particular, it can also be used when the molding ( 32 ) is transferred to the heating wheel ( 1 ) and when the molding ( 32 ) is transferred from the heating wheel ( 1 ) to a further transfer device.

In a constructive realization of the aligning element ( 17 ) and the positioning element ( 24 ), both the described realization of the aligning element ( 17 ) as a funnel-like fork and the positioning element ( 24 ) as a roller-like part can take place, but it is also possible for the gripping device ( 33 ) to be provided with a suitably positioned roller which is inserted into a tapering receiving element associated with the holding element ( 23 ). Other variants of the described direct mechanical alignment of the parts relative to one another are also conceivable, for example non-contact alignment due to magnetic fields acting on them.

Claims (19)

1. A method for transferring moldings in the area of a device for blow molding containers made of a thermoplastic material, in which a preform is fed to at least one heating device for temperature control and at least one blow molding station for blow molding and in which the moldings are moved along by at least part of their transport path Gripping element are held, characterized in that the molded article ( 32 ) is positioned before an access of the gripping element ( 33 ) by a holding element ( 23 ), relative to the stationary a positioning element ( 24 ) is arranged that relative to the gripping element ( 33 ) a aligning element ( 17 ) is arranged in a fixed position and that with a relative movement of the gripping element ( 33 ) in the direction of the molding ( 32 ) to be gripped, the aligning element ( 17 ) relative to the positioning element ( 24 ) and thus also the gripping element ( 33 ) relative is positioned to the molding ( 32 ). 2. The method according to claim 1, characterized in that the gripping element ( 33 ) is positioned by a transfer wheel ( 5 , 6 , 7 , 13 , 17 ). 3. The method according to claim 1 or 2, characterized in that the gripping element ( 33 ) is positioned relative to the transfer wheel ( 5 , 6 , 7 , 13 , 14 ) in the radial direction. 4. The method according to any one of claims 1 to 3, characterized in that the holding element ( 23 ) in the loading area of the blowing station ( 12 ) is arranged. 5. The method according to any one of claims 1 to 3, characterized in that the holding element ( 23 ) is arranged in the region of the heating device ( 8 ). 6. The method according to any one of claims 1 to 5, characterized in that positioning is carried out transversely to a direction of movement of the gripping element ( 33 ) by a tapered guide in cooperation of the Ausrichtele element ( 17 ) and the positioning element ( 24 ) and that positioning becomes effective in the direction of movement of the gripping element ( 33 ) by an effective stop. 7. The method according to any one of claims 1 to 6, characterized in that the positioning element ( 24 ) is used in a roll-like manner. 8. The method according to any one of claims 1 to 7, characterized in that the alignment element ( 17 ) is used like a fork. 9. The method according to any one of claims 1 to 6, characterized in that the positioning element ( 24 ) is used like a fork. 10. The method according to any one of claims 1 to 6, characterized in that the alignment element ( 17 ) is used in a roll-like manner. 11. The method according to any one of claims 1 to 10, characterized in that the molding ( 32 ) is handled standing with a mouth oriented vertically downwards. 12. The method according to any one of claims 1 to 10, characterized in that the molding ( 32 ) is handled hanging with a mouth oriented vertically upwards. 13. The method according to any one of claims 1 to 12, characterized in that the molding ( 32 ) within the blowing station ( 12 ) after a transfer from a stretching rod ( 27 ) is stretched in the longitudinal direction. 14. The method according to any one of claims 1 to 13, characterized in that the molding ( 32 ) after a transfer within the blowing station ( 12 ) from a pressurized medium is expanded and biaxially oriented. 15. Device for transferring moldings in the area of a device for blow molding containers made of a thermoplastic material, in which the device for blow molding has a heating device for tempering preforms and at least one blow molding station for blow molding the preforms and which is provided with at least one gripping element which holds the moldings along at least part of their transport path within the device for blow molding, characterized in that the gripping element ( 33 ) is rigidly coupled to an alignment element ( 17 ) that in the area of a holding element ( 32 ) supporting the molding ( 32 ) 23 ) a positioning element ( 24 ) is angeord net and that the alignment element ( 17 ) and the gripping element ( 33 ) relative to each other is designed to fit and are arranged relative to each other in such a way that with a relative movement of the gripping element ( 33 ) in the direction of that Haltele element ( 23 ) by contact between rule the Ausrichtele element ( 17 ) and the positioning element ( 24 ) from the direction of the gripping element ( 33 ) relative to the molding ( 32 ) is predetermined. 16. The apparatus according to claim 15, characterized in that the alignment element ( 17 ) as a widening fork and the positioning element ( 24 ) is designed as a roller. 17. The apparatus according to claim 15, characterized in that the alignment element ( 17 ) is designed as a roller-like element and the positioning element ( 24 ) as an expanding fork. 18. Device according to one of claims 15 to 17, characterized in that the gripping element ( 33 ) is coupled to a stop for limiting a movement path. 19. Device according to one of claims 15 to 17, characterized in that in the region of a handle of the alignment element ( 17 ) in the positioning element ( 24 ) a decreasing play is provided for carrying out a constant alignment.