DE102014011370B3 - Apparatus and method for blow molding containers - Google Patents

Abstract

The invention relates to a device for blow-molding containers made of a thermoplastic material with at least two treatment stations (1, 2) with tools (42, 55) for receiving and holding preforms (10), for example a heating device (2) for heating the preforms (2). 10), and a blowing device (1) for forming containers of preforms (10) provided with blowing stations, with at least one transfer device (23) for transferring the preforms (10) from one treatment station (1, 2) to another Treatment station (1, 2) with tools (42, 55) for removing the preforms (10) from the treatment station (1, 2), the transport of the preforms (10) to the further treatment station (1, 2) and for delivering the Preforms (10) to the further treatment station (1, 2) are designed, wherein at least one of the treatment stations (1, 2) and / or the at least one transfer device (23) at least one mechanical Steue in that the tools (42, 55) have an engagement region (56) in relation to one another and are arranged relative to one another such that the movement of the tools (42, 55 ) is effected without contact in a normal operation, and wherein the drive of the treatment stations (1, 2) and / or the transfer device (23) takes place by means of individual drives which are synchronized in terms of control, wherein the tools (42, 55) of at least one of the treatment stations (1, 2) and / or the transfer device (23) are movable out of the engagement area in the event of a malfunction by a movement of at least one section (50, 51) of the control device (44).

Description

The invention relates to a device for blow molding containers made of a thermoplastic material with at least two treatment stations with tools for holding and holding preforms, for example a heater for heating the preforms, and a blower for forming containers from preforms, which is provided with blow molding stations, with at least one transfer device for transferring the preforms from one treatment station to another treatment station with tools designed to remove the preforms from the treatment station, transport the preforms to the further treatment station and deliver the preforms to the further treatment station, wherein at least one of Treatment stations and / or the at least one transfer device have at least one mechanical control device for specifying the movement of the tools, wherein the tools in their movement towards each other an egg Have ngriffsbereich and are arranged to each other that the movement of the tools in a normal operation is carried out without contact, and wherein the drive of the movement of the tools of the treatment stations and / or the transfer device by means of individual drives, which are synchronized control technology, and a method for securing tools for transporting preforms or containers, preferably mandrels or pliers, in such a device.

Containers are used for packaging liquid foods and beverages. These are in particular bottles made of glass or plastic or so-called pouches, but in this application containers are also understood to mean preforms, closures or the like. The containers are created in a manufacturing process on different devices and then filled in another device. During the manufacturing and filling process, it is necessary to transport the containers and transfer them from one station to the other between the individual process stages.

As an example, the production of containers made of plastic in a blowing device may be mentioned here. In a container molding by blowing pressure preforms of a thermoplastic material, such as preforms made of PET (polyethylene terephthalate), supplied to different processing stations within a blow molding machine. Typically, such a blow molding machine has a heating device and a blowing device, in the region of which the previously tempered preform is expanded by biaxial orientation to form a container. The expansion takes place with the aid of compressed air, which is introduced into the preform to be expanded. The procedural sequence in such an expansion of the preform is in the DE 43 40 291 A1 explained. The introductory mentioned introduction of the pressurized gas also includes the introduction of compressed gas into the developing container bubble and the introduction of compressed gas into the preform at the beginning of the blowing process.

The basic structure of a blowing station for container molding is in the DE 42 12 583 A1 described. Possibilities for tempering the preforms are in the DE 23 52 926 A1 explained.

Within the blow molding apparatus, the preforms as well as the blown containers can be transported by means of different handling devices. In particular, the use of transport mandrels, onto which the preforms are plugged, has proven to be useful. The preforms can also be handled with other support devices. The use of gripper tongs for handling preforms and the use of expansion mandrels which are insertable into a muzzle region of the preform for mounting are also among the available constructions.

Handling of containers using transfer wheels, for example, in the DE 199 06 438 A1 described in an arrangement of the transfer wheel as a transfer station between a blowing wheel and an output path.

Originally, the transport devices in such a processing machine, especially those that had to work very closely together at high speed, for example, exact pitch or synchronously, coupled purely mechanically with each other. For example, the inlet and outlet stars of a filler or a labeling machine by direct, slip-free drive connection, ie by gears, timing belt and pulleys, with each other so rigidly "pitch true" connected. In this solution, an accident, such as a power failure, led only to a machine downtime, but not to a loss of synchronous operation of the interconnected machine components.

For cost reasons is dispensed with a rigid coupling, which can be dispensed with high-priced, installation-intensive and wear-friendly gearbox, drive shafts, etc. Instead, the individual components such as inlet star, outlet star, rotor of the treatment machine, etc., each provided with their own drive motors, wherein the drive motors are, for example, servo motors, which are preferably also equipped with encoders. Rotary encoders report the true actual angle of rotation back to the controller. In the case of deviations between the setpoint and the actual rotation angle, a correction takes place automatically so that the motor reaches the setpoint rotation angle. This applies to "static" positioning tasks in which a motor is to achieve a setpoint rotation angle and then remains without further rotation until it comes to a renewed change in the target rotation angle. Furthermore, this also applies to "dynamic" positioning tasks in which rotational movements over several hours with each other should run simultaneously and synchronously to each other.

In the presence of a fault that deviates from the rotational synchronism rotary element is switched without drive and freely rotatable. At the same time, the entire system is brought to a standstill. Due to the presence of the residual energy inherent in the freely connected rotary element, which is degraded more slowly than that of the actively braked rotary element, it can correspondingly result in a "overtaking" by the released element and thus in a collision. According to DE 10 2013 014 618 A1 are used as controls pinion gears and gears, each with a control is attached to a transfer wheel. In the event of a deviation from the rotational synchronism, an excessive offset is mechanically limited by positive locking when the bolt and flank of the respective control element come into contact.

The object of the present invention is to improve an apparatus and method for blow-molding of containers of the aforementioned type, that to reduce the risk of damage in case of loss of synchrony in case of failure.

The object is achieved according to the invention in terms of the device in that the tools of at least one of the treatment stations and / or the transfer device are movable out of the engagement region in a fault by a movement of at least a portion of the control device.

This causes a collision of the tools is avoided when a loss of synchrony, for example, the drives and thus the tools occurs.

An advantageous teaching of the invention provides that the mechanical control is a cam control. This represents a preferred simple control option.

An advantageous teaching of the invention provides that the portion of the cam control is designed to be movable corresponding to the engagement region, wherein it is preferably a vertical movement. It has been found that this implementation is particularly effective and inexpensive

An advantageous teaching of the invention provides that movement of the control device via a drive, preferably via hydraulic cylinders. An advantageous teaching of the invention provides that it is the tools around mandrels or pliers.

An advantageous teaching of the invention provides that a plurality of sections are provided, which are coupled mechanically in their movement.

An advantageous teaching of the invention provides that the treatment stations are a heating device, a blowing device, a sterilization device, a cooling device, an additional heating device, a cleaning device, a labeling device, and / or a filling device.

The object is achieved according to the invention with regard to the method in that the tools of at least one of the treatment stations and / or the transfer device are moved out of the engagement region in the event of a malfunction by a movement of at least one section of the control device.

An advantageous teaching of the invention provides that the portion of the cam control is moved corresponding to the engagement region, which is preferably a vertical movement.

In the drawing, an embodiment of the invention is shown schematically. Show it:

1 an overview of a device for blow molding of containers, which has a heating device, provided with blowing stations rotating blowing wheel and various transfer devices,

2 a spatial representation of a transfer device with mounted tools,

3 a spatial representation of a transfer section of a heater in engagement with an indicated by their tools transfer device whose tools are in engagement with the tools of the heater,

4 a representation too 3 without preforms,

5 a spatial representation of a transfer section of a heater in engagement with an implied by their tools transfer device whose tools are not in engagement with the tools of the heater, and

6 a representation too 5 without preforms.

1 shows the basic structure of a blow molding machine, with a rotating blowing wheel 1 and a heater 2 is equipped for preforms to be tempered. Along a circumference of the blowing wheel 1 are blowing stations 3 arranged, each mold carrier 4 . 5 exhibit. The mold carriers 4 . 5 are used for positioning of mold elements, typically of mold halves 8th . 9 , The mold carriers 4 . 5 are over pivot bearings 12 . 13 rotatable with the mold carriers 4 . 5 coupled. The blowing wheel 1 rotates relative to a Blasradachse 14 ,

At the in 1 illustrated embodiment, the heater 2 with a transport chain 18 provided, which are the preforms to be heated along heating elements 16 transported. The heating elements 16 For example, they can be designed as IR radiators. But it is also possible to provide operating in other frequency ranges spotlights or convection heating. In the illustrated embodiment, the heating elements are along the transport path of the preforms 16 arranged on one side and the heating elements 16 Opposite are reflectors 17 intended. Basically, a two-sided arrangement of heating elements 16 realizable. In the area of the transport chain 18 are the preforms of carrying devices or tools (in 1 not shown) held. This may be, for example, a holder of the preforms via pliers or expanding mandrels

An input of the preforms can About a feeder 20 respectively. The feeder 20 is through a transfer wheel 23 with the heater 2 coupled.

The heater 2 is from a transfer wheel 25 with the blowing wheel 1 coupled and in the field of blowing stations 3 ready-blown containers are blown off 1 to a picking wheel 26 to hand over. The picking wheel 26 is with an output wheel 27 coupled to the blown container in the area of a discharge line 29 transferred. In the area of the output wheel 27 If necessary, a change in the spatial orientation of the blown containers can be performed.

In order to allow a high heat input into the preforms without the risk of overheating of the outer surface, it is possible in the region of the heater 2 in addition to the heating elements 16 To arrange blower, the cooling air in the area of the preforms lead. For example, it is possible, in the transport direction of the preforms alternately heating elements 16 and to position fans one after the other.

In order to be able to transform a preform into a container in such a way that the container has material properties which ensure a long usability of foods filled inside the container, in particular of beverages, special process steps must be followed in the heating and orientation of the preforms. In addition, advantageous effects can be achieved by adhering to special dimensioning regulations.

As a thermoplastic material different plastics can be used. For example, PET, PEN or PP can be used.

The expansion of the preform during the orientation process is carried out by compressed air supply. The compressed air supply is in a Vorblasphase in which gas, for example, compressed air, is supplied at a low pressure level and a subsequent main blowing phase divided, is supplied to the gas at a higher pressure level. During the pre-blowing phase, compressed air is typically used at a pressure in the interval of 10 bar to 25 bar and during the main blowing phase compressed air is supplied at a pressure in the interval of 25 bar to 40 bar.

2 shows a spatial representation of the transfer wheel in an analogous or alternative embodiment of the aforementioned transfer wheels 23 . 25 . 26 with a servo motor arranged on the transfer wheel 28 ,

The transfer wheel 25 sits on a bearing housing 30 , in which also the drive shaft (not shown) is mounted. The transfer wheel 25 has a carrier 31 on, on which the receiving elements in the form of pliers 32 are arranged for the container / preforms. The transfer wheel 25 has a first and a second control cam 33 . 34 on, about the movement of the pliers 32 with rollers arranged in connection with the cams 35 to be controlled. The pliers 32 are either pivoted or moved forward / backward to provide the necessary at a transfer point division in the transfer.

3 shows a transfer section 40 a heating device 2 , This has a guide wheel 41 on that the curve guidance of the carrying devices / tools 42 in the form of thorns 42 takes over. At the thorns 42 are preforms 10 arranged on the inside held by a clamping mechanism 43 (see also 4 ). The transfer section 40 has a control wheel 44 on, at which a first curve control 45 and a second curve control 46 are arranged. The first curve control 45 has a curve 47 , and the second curve control 46 has a curve 48 on. Within the curves 47 . 48 are control roles 49 arranged over the mechanically with the mandrel 42 are coupled, so that the vertical movement of the mandrels 42 and the opening and closing of the clamping mechanism 43 is controlled. This is the thorn 42 against a spring 50 vertically movably mounted. The first turn 47 present role 49 is connected to a fork (not shown), which is in the mandrel 42 engages and above it the thorn 42 vertically depending on the position of the curve 47 shifts. The second turn 48 present role 49 is with the clamping mechanism 43 connected. If the roller is lowered vertically, the clamping mechanism opens 43 and gives the tense preform 10 free.

When transporting the mandrels through the heater 2 in the heating area, the curves show 47 . 48 a constant horizontal shape, so that the vertical position of the spines 42 does not change and the preforms 10 in the clamping mechanisms 43 are locked. In the transfer section 40 show the curves 47 . 48 a section 51 . 52 on, in which the curves 47 . 48 as a bow 53 . 54 are formed, which points downwards, so that in the curves 47 . 48 located roles 49 undergo a change in position down, causing the spines 42 vertically according to the shape of the bow 53 be moved, and the clamping mechanism 43 according to bow 54 is opened.

By the down procedure, the preforms become 10 in the correct position for the intervention in the appropriate area provided with the tools 55 the transfer wheel 23 brought. At the tools 55 they are pliers 55 , These are in the 3 to 6 representative of the transfer wheel 23 shown. The pliers 55 resort to taking over the preforms 10 the preform 10 for example, below a prefabricated estuarine area 11 of the preform 10 from the outside. The pliers 55 rotate in the direction of movement B, where they are on the transfer wheel 23 be pivoted so that they are in the intervention area 56 between thorns 42 and pliers 55 additionally be pivoted so that they correspond with the arrangement of the dome. As in 3 can be seen, includes the right of the three pliers shown 55 at the thorn 42 locked preform 10 below its mouth area 11 in the open state. Subsequently, the thorn 42 with the preform 10 lowered (middle pliers 55 ), then the pliers 55 around the preform 10 closed so that these are the preform 10 engages, the clamping mechanism 43 solved and the thorn 42 raised (left tongs 55 ). The preform 10 is thus out of the heater 2 taken and to the transfer wheel 23 to hand over. The movement of the mandrels and the pliers is synchronized, so that the two tools 42 . 55 in the intervention area 56 however, do not touch while the synchronization is in progress.

If this synchronization is lost, for example due to a drive fault or the like, the tools would become 42 . 55 touch and it would come to damage. To avoid this, the invention provides that the curve sections 51 . 52 , which is a lowering movement of the spines 42 in the engagement area and the opening of the clamping mechanism 43 and thus the release of the preform 10 cause it to move, so that it is possible to turn the curve sections 50 . 51 so move out of their operational position that the spines 42 no longer in the intervention area 56 arrive and thus no contact with the pliers 55 can arise and consequently no damage to the tools 42 . 56 can be done.

Alternatively or additionally, corresponding sections (not shown) of the curves 33 . 34 on the transfer wheel 23 that the pliers 55 in the range of motion 56 be carried out, so that it is possible to move the curve sections so from their operating position that the pliers 55 no longer in the intervention area 56 reach and thus no contact and consequently no damage to the tools 42 . 55 can be done. This is not shown in the figures, the expert can analogously to the following, the alternative embodiment or an adaptation of the invention to the transfer of the preforms to the blowing stations 3 the blowing wheel 1 or the transfer of the containers from the blowing stations 3 the blowing wheel 1 to the output wheel 27 to carry out his professional activity as part of his work.

To move the curve sections 51 . 52 These are mechanically with each other over a plate 57 connected with guide rods 58 vertically guided movable in the direction of movement C is arranged on this. Furthermore, there is a drive 60 provided by a connection 59 with the plate 55 connected is. In 3 and 4 is the plate 57 presented in the operating situation in which the tools 42 in the intervention area 56 are located. In 5 and 6 is the plate 57 represented in the fault situation, for example, loss of synchrony, in which the tools 42 outside the intervention area 56 are located.

The vertical stroke of the curve sections 51 . 52 the curves 47 . 48 the curve control 45 . 46 causes the spines 42 at the transport level of the heater 2 remain and thus the tips of the spines 42 on which the clamping mechanisms 43 are not in the intervention area 56 be lowered, bringing a touch with the pliers 55 is excluded. Like here in 5 is shown, are the at the thorns 42 located preforms 10 in this embodiment, still in the intervention area 56 , In the case of loss of synchrony there is still the possibility that the pliers 55 and preforms 10 touch. In this case, it would possibly lead to a knocking off of the preforms 10 from the clamping mechanism 43 but not to damage the pliers 55 / mandrels 42 ,

LIST OF REFERENCE NUMBERS

1

blow wheel

2

heater

3

blowing station

4

mold carrier

5

mold carrier

8th

mold

9

mold

10

preform

11

mouth area

12

pivot bearing

13

pivot bearing

14

Blasradachse

16

heating element

17

reflector

18

transport chain

20

feeding

23

transfer wheel

26

extraction wheel

27

output wheel

28

servomotor

29

delivery line

30

bearing housing

31

carrier

32

tongs

33

cam

34

cam

35

role

40

Transfer section

41

guide wheel

42

Support means / tool / mandrel

43

clamping mechanism

44

control wheel

45

cam control

46

cam control

47

Curve

48

Curve

49

role

50

feather

51

curve section

52

curve section

53

bow

54

bow

55

Tool / pliers

56

engagement area

57

plate

58

guide rod

59

connection

60

drive

61

A

Transport direction mandrels

B

Movement direction pliers

C

Direction of movement plate

Claims (9)

Device for the blow-molding of containers made of a thermoplastic material with at least two treatment stations ( 1 . 2 ) with tools ( 42 . 55 ) for receiving and holding preforms ( 10 ), for example a heating device ( 2 ) for heating the preforms ( 10 ), and a blowing device ( 1 ) for forming containers from preforms ( 10 ), which is provided with blowing stations, with at least one transfer device ( 23 ) for the transfer of the preforms ( 10 ) from a treatment station ( 1 . 2 ) to another treatment station ( 1 . 2 ) with tools ( 42 . 55 ) used to remove the preforms ( 10 ) from the treatment station ( 1 . 2 ), the transport of the preforms ( 10 ) to the further treatment station ( 1 . 2 ) and for the delivery of the preforms ( 10 ) to the further treatment station ( 1 . 2 ), wherein at least one of the treatment stations ( 1 . 2 ) and / or the at least one transfer device ( 23 ) at least one mechanical control device ( 44 ) for specifying the movement of the tools ( 42 . 55 ), the tools ( 42 . 55 ) in their movement to each other an intervention area ( 56 ) and are arranged to one another such that the movement of the tools ( 42 . 55 ) occurs in a normal operation without contact, and wherein the drive of the treatment stations ( 1 . 2 ) and / or the transfer device ( 23 ) is effected by means of individual drives which are synchronized in terms of control technology, characterized in that the tools ( 42 . 55 ) at least one of the treatment stations ( 1 . 2 ) and / or the transfer device ( 23 ) in a fault by moving at least one section ( 50 . 51 ) of the control device ( 44 ) are movable out of the engagement area. Device according to claim 1, characterized in that the mechanical control is a cam control ( 45 . 46 ). Device according to claim 2, characterized in that the section ( 51 . 52 ) of the cam control ( 45 . 46 ) corresponding to the engagement area ( 56 ) is made movable, which is preferably a vertical movement (C). Device according to one of claims 2 to 3, characterized in that the movement of the Control via a drive ( 60 ), preferably via pneumatic cylinder. Device according to one of Claims 1 to 4, characterized in that the tools are mandrels ( 42 ) or pliers ( 55 ). Device according to one of claims 2 to 4, characterized in that several sections ( 51 . 52 ) are provided, which are mechanically coupled with each other in their movement. Device according to one of claims 1 to 6, characterized in that it is at the treatment stations to a heating device ( 2 ), a blowing device ( 1 ), a sterilization device, a cooling device, an additional heating device, cleaning device, labeling device, and / or filling device. Method for securing tools ( 42 . 55 ) for receiving and transporting preforms ( 10 ) or containers, preferably mandrels or pliers, in blow molding apparatus, in particular according to one of claims 1 to 7, of a thermoplastic material having at least two treatment stations ( 1 . 2 ), for example a heating device ( 1 ) for heating preforms ( 10 ), and / or a blowing device ( 2 ) for forming containers from preforms ( 10 ), which is provided with blowing stations, and with at least one transfer device ( 23 ) for the transfer of the preforms ( 10 ) from a treatment station ( 1 . 2 ) to another treatment station ( 1 . 2 ) with tools, with which the preforms ( 10 ) from the treatment station ( 1 . 2 ), to the further treatment station ( 1 . 2 ) and to the further treatment station ( 1 . 2 ), whereby the movement of the treatment stations ( 1 . 2 ), and / or the transfer device ( 23 ) is carried out by means of individual drives which are synchronized in terms of control technology, the tools ( 42 . 55 ) in their movement to each other an intervention area ( 56 ) and are arranged to one another such that the movement of the tools ( 42 . 55 ) in a normal operation without contact, and wherein the movement of the tools ( 42 . 55 ) by a mechanical control ( 44 ), preferably a cam control ( 45 . 46 ), characterized in that the tools ( 42 . 55 ) at least one of the treatment stations ( 1 . 2 ) and / or the transfer device ( 23 ) in a fault by moving at least one section ( 51 . 52 ) of the control device ( 44 ) out of the intervention area ( 56 ) are moved out. Method according to claim 8, characterized in that the section ( 51 . 52 ) of the cam control ( 45 . 46 ) corresponding to the engagement area ( 56 ), which is preferably a vertical movement (C).

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