DE102021104860B4 - Method and device for providing preforms and method and system for producing containers - Google Patents

Abstract

Method for providing and feeding preforms to a device for the production of containers by forming the preforms by pressurizing them with a fluid, comprising:a) placing the preforms in a filling container (18) in a transfer device (19) for transferring the preforms into one Storage container (12), b) monitoring a fill level (29) in the storage container (12), c) automatically emptying the filling container (18) into the storage container (12) when the fill level (29) in the storage container (12) reaches a first limit value ( 31), d) removal of the preforms from the storage container (12) in a conveying stream, characterized in that a second limit value (32) of the fill level (29) is monitored on the storage container (12), the second limit value (32) being larger or is equal to the first limit value (31), that a filling state (30) is determined at the filling container (18), and that if the second limit value (32) in the storage container (12) is undershot, the filling state (30) in the filling container (18) is evaluated to control filling of the filling container (18) or replacing it with a filled filling container (18).

Description

The invention relates to a method for providing and feeding preforms according to the preamble of claim 1. The invention further relates to a device according to the preamble of claim 14, in particular for carrying out the method.

Plastic containers are produced by forming preforms by applying pressure with a fluid, i.e. pneumatically or hydraulically, in particular in a blow molding or stretch blow molding process or in the so-called form-fill process. In particular, these are containers made of PET, preferably bottles.

The preforms are kept ready as bulk material in a storage container and removed from it in a conveying stream. The flow leads to a heating device in which the preforms are thermally conditioned. The preforms are transferred from the heating device to a device with blow molds using a transfer conveyor.

An unintentional interruption of the flow from the storage container should be avoided. The contents or fill level of the storage container is therefore monitored. As soon as a first limit value is undershot, preforms are automatically transferred from a filling container into the storage container. The filling container is then immediately refilled or replaced with a filled one. This means that each time the preforms are transferred from the filling container to the storage container, the filling container is also refilled or replaced. This shows such a state of the art EP 3 239 077 A1 .

The object of the present invention is to create a method with which the overall effort involved can be reduced.

1. a) Platzieren der Vorformlinge in einem Füllbehälter in einer Umfüllvorrichtung zum Umfüllen der Vorformlinge in einen Vorratsbehälter,
2. b) Überwachen eines Füllstands im Vorratsbehälter,
3. c) automatisches Entleeren des Füllbehälters in den Vorratsbehälter, wenn der Füllstand im Vorratsbehälter einen ersten Grenzwert unterschreitet,
4. d) Entnahme der Vorformlinge aus dem Vorratsbehälter in einem Förderstrom,

umfassenden Ablauf, ist insbesondere vorgesehen, dass am Vorratsbehälter ein zweiter Grenzwert des Füllstands überwacht wird, wobei der zweite Grenzwert größer oder gleich dem ersten Grenzwert ist, dass am Füllbehälter ein Befüllungszustand bestimmt wird und dass bei Unterschreiten des zweiten Grenzwerts im Vorratsbehälter der Befüllungszustand im Füllbehälter ausgewertet wird, um eine Befüllung des Füllbehälters oder einen Ersatz desselben durch einen befüllten Füllbehälter zu steuern. Demnach wird der zweite Grenzwert vor dem ersten Grenzwert zusätzlich berücksichtigt. Dadurch können die Befüllung oder der Austausch des Füllbehälters noch besser und vorausschauender geplant und durchgeführt werden. Das erfindungsgemäße Verfahren wird vorzugsweise für die Herstellung von Behältern in einem Blasprozess oder im Form-Fill-Verfahren verwendet, jeweils mit oder ohne Reckstange.To solve the problem, the method according to the invention has the features of claim 1. Starting from one the steps

1. a) placing the preforms in a filling container in a transfer device for transferring the preforms into a storage container,
2. b) monitoring a fill level in the storage container,
3. c) automatic emptying of the filling container into the storage container when the fill level in the storage container falls below a first limit value,
4. d) removing the preforms from the storage container in a conveying stream,

Comprehensive process, it is in particular provided that a second limit value of the fill level is monitored on the storage container, the second limit value being greater than or equal to the first limit value, that a filling state is determined on the filling container and that if the second limit value in the storage container is undershot, the filling state in the filling container is evaluated in order to control filling of the filling container or a replacement of the same with a filled filling container. Accordingly, the second limit value is also taken into account before the first limit value. This means that the filling or replacement of the filling container can be planned and carried out even better and more proactively. The method according to the invention is preferably used for the production of containers in a blowing process or in the form-fill process, in each case with or without a stretch rod.

• - bei Unterschreiten des zweiten Grenzwerts im Vorratsbehälter und zugleich leerem Füllbehälter der Füllbehälter gefüllt wird oder durch einen gefüllten Füllbehälter ersetzt wird,
• - der gefüllte Füllbehälter automatisch in den Vorratsbehälter entleert wird,
• - und der nun wieder leere Füllbehälter gefüllt oder durch einen gefüllten Füllbehälter ersetzt wird, ohne das Unterschreiten eines der Grenzwerte des Füllstands abzuwarten.

According to a further idea of the invention it can be provided that

• - if the storage container falls below the second limit value and the filling container is empty at the same time, the filling container is filled or is replaced by a filled filling container,
• - the filled filling container is automatically emptied into the storage container,
• - and the now empty filling container is filled or replaced by a filled filling container without waiting for the fill level to fall below one of the limit values.

The filling container is therefore only filled again when the storage container is almost empty again, namely its fill level falls below the second limit value. In this way, the effort required to fill the filling container can be almost halved. A complete halving of the effort is not possible because filling the filling container and the storage container cannot be carried out in an arbitrarily short time and the preforms are continuously conveyed out of the storage container.

1. a) der Füllstand im Vorratsbehälter den zweiten Grenzwert unterschreitet und zugleich der Füllbehälter leer ist, oder
2. b) das Füllen oder Ersetzen des zuvor automatisch in den Vorratsbehälter entleerten Füllbehälters nicht innerhalb einer definierten Zeitspanne erfolgt.

According to a further idea of the invention, a signal can at least be generated if

1. a) the filling level in the storage container falls below the second limit value and at the same time the filling container is empty, or
2. b) the filling or replacement of the filling container that was previously automatically emptied into the storage container does not take place within a defined period of time.

The signal according to a) signals to the operating personnel the need to refill the filling container. Transferring from the filling container into The storage container is automatically filled by a corresponding transfer device when the fill level in the storage container falls below the first limit value.

The signal according to b) ensures that the previously emptied filling container is refilled. The time period also depends on the speed of movement of the filling container and the time required to fill or replace the filling container and is preferably between one and five minutes.

Of course, the signal can also be provided for both cases a) and b).

According to a further idea of the invention, the signal can be an optical and/or acoustic signal. The signal is preferably output by a buzzer, a horn, a loudspeaker, a light, a signal lamp. For the purposes of the invention, an indication on a display is also an optical signal.

According to a further idea of the invention, it can be provided that the filling container is used as a transport container and the filled transport container is fed to the decanting device and emptied transport containers are removed. The filling container therefore has a dual function. Alternatively, the filling container is installed at the location of the transfer device or is part of the transfer device and is filled cyclically.

According to a further idea of the invention, the fill level in the storage container can be determined by one or more light barrier measurements on the storage container. This is a well-known and established technique for determining the filling level.

According to a further idea of the invention, the limit values can be monitored by optical sensors. Optical sensors are proven, easy to handle and control. In particular, these are cameras, infrared sensors and light barriers.

According to a further idea of the invention, the optical sensors can monitor at least two linear areas in the storage container, the areas lying one above the other at a distance and in particular running transversely to one another. The linear areas preferably run approximately in the middle or within a middle third of the storage container, based on the length and width of the storage container. One of the linear areas advantageously extends parallel to the conveying direction of a discharge conveyor, which is arranged under the storage container.

According to a further idea of the invention, the fill level in the storage container can be determined by measuring the weight of the storage container. By determining the weight of the storage container, the filling level can be determined relatively precisely since the preforms are formed with the same mass.

According to a further idea of the invention, a distinction should only be made between “full” and “empty” for the filling status of the filling container. This simplifies the control of the process. The filling status can be saved in a control device and used to control the process.

According to a further idea of the invention, a “full” filling state can be determined for the filling container by determining or detecting the insertion of the filling container into the decanting device. It is not the content of the filling container that is detected, but rather its presence in the decanting device. This also simplifies the process. “Full” can be noted in the control unit until a different filling status is detected.

• - ein Kippvorgang des Füllbehälters,
• - ein Verlassen einer Ausgangsstellung des Füllbehälters,
• - eine Bewegung des Füllbehälters aus der Ausgangsstellung in eine Übergabestellung,
• - ein Erreichen der Übergabestellung,
• - ein Verlassen der Übergabestellung,
• - eine Rückbewegung in die Ausgangsstellung oder
• - ein Erreichen der Ausgangsstellung

festgestellt oder detektiert werden. Der Füllbehälter ist zwischen Ausgangsstellung und Übergabestellung bewegbar. In der Übergabestellung fallen die Vorformlinge in den Vorratsbehälter, in der Ausgangsstellung ist der Füllbehälter in Bereitschaft und die Vorformlinge können nicht in den Vorratsbehälter fallen. Der Befüllungszustand „leer“ wird angenommen, sobald eine oder mehrere der genannten Bedingungen erfüllt sind, insbesondere sofern bisher der Befüllungszustand „voll“ galt oder in der Steuerung vorlag.According to a further idea of the invention, an “empty” filling state can be determined for the filling container by:

• - a tilting process of the filling container,
• - leaving a starting position of the filling container,
• - a movement of the filling container from the starting position into a transfer position,
• - reaching the handover position,
• - leaving the transfer position,
• - a return movement to the starting position or
• - reaching the starting position

be determined or detected. The filling container can be moved between the starting position and the transfer position. In the transfer position the preforms fall into the storage container, in the starting position the filling container is on standby and the preforms cannot fall into the storage container. The filling state “empty” is assumed as soon as one or more of the conditions mentioned are met, especially if the filling state was previously “full” or was present in the control.

The invention also relates to a method according to claim 13, namely for producing containers by providing preforms, feeding the preforms in a conveying stream, thermal conditioning of the preforms and subsequent forming by applying pressure with a fluid, in particular into containers in a blow molding or stretch blow molding process or in the form-fill process. According to the invention, the method described above for providing and feeding the preforms is used.

1. a) einen Vorratsbehälter, aus dem die Vorformlinge in einem Förderstrom entnehmbar sind,
2. b) eine erste Überwachungseinrichtung zum Überwachen eines Füllstands an Vorformlingen in Vorratsbehältern,
3. c) einen Füllbehälter, in dem die Vorformlinge platziert werden,
4. d) eine Umfüllvorrichtung zum automatischen Umfüllen der Vorformlinge aus dem Füllbehälter in den Vorratsbehälter in Abhängigkeit von einem ersten Grenzwert des Füllstands im Vorratsbehälter.

The invention also relates to a device according to claim 14. The device is intended for providing preforms for a device for producing containers by forming the preforms by pressurizing them with a fluid, in particular in a blow molding process or stretch blow molding process or in the form-fill process, and includes in particular:

1. a) a storage container from which the preforms can be removed in a conveying stream,
2. b) a first monitoring device for monitoring a fill level of preforms in storage containers,
3. c) a filling container in which the preforms are placed,
4. d) a transfer device for automatically transferring the preforms from the filling container into the storage container depending on a first limit value of the fill level in the storage container.

According to the invention, the device in particular has a second monitoring device for determining the filling state in the filling container. With the device, the method according to the invention can be carried out advantageously, even according to all the features of the embodiments of the method subclaims. The second monitoring device ensures that the filling state of the filling container can preferably be determined qualitatively or even recorded quantitatively. The second monitoring device can also be integrated into a controller, in particular into a control device.

According to the invention, the first monitoring device for monitoring the first limit value is also provided for monitoring a second limit value of the fill level in the storage container. Monitoring two limit values enables predictive process control.

1. a) der Füllstand im Vorratsbehälter den zweiten Grenzwert unterschreitet und zugleich der Füllbehälter leer ist, oder
2. b) das Füllen oder Ersetzen zuvor des automatisch in den Vorratsbehälter entleerten Füllbehälters nicht innerhalb einer definierten Zeitspanne erfolgt.

According to a further idea of the invention, a signaling device can be provided with which a signal can be output at least when

1. a) the filling level in the storage container falls below the second limit value and at the same time the filling container is empty, or
2. b) the filling or replacement of the filling container that was automatically emptied into the storage container does not take place within a defined period of time.

The signaling device outputs a signal in one of cases a), b) or in both cases. The signaling device can be controlled by an appropriately set up control device.

According to a further idea of the invention, the signaling device can output an optical and/or acoustic signal. The specific design of the signaling device should depend on the environmental conditions at the location of the device and on the intended work processes. The optical signal can also be a representation on a display.

According to a further idea of the invention, it can be provided that the first monitoring device contains at least one optical sensor. In particular, it is a light barrier. An optical sensor in the sense of the invention is also a camera with image processing.

According to a further idea of the invention, the monitoring device can have a first sensor for monitoring the first limit value and a second sensor for monitoring the second limit value. By splitting them into two sensors, they can be designed more simply.

According to a further idea of the invention, the particularly optical sensors can monitor at least a first line-shaped area for the first limit value and a second line-shaped area for the second limit value.

According to a further idea of the invention, the two linear areas can run transversely to one another. The linear areas preferably extend in a horizontal plane.

According to a further idea of the invention, the first linear region can run in the direction of the conveying flow, in particular parallel to it. The flow rate is the quantity of preforms on a discharge conveyor arranged below the storage container. The preforms fall from a gap onto the discharge conveyor, the gap preferably extending on an underside of the storage container and in particular over its length.

According to a further idea of the invention, the first monitoring device can contain at least one sensor for determining a weight of the storage container. The weight determination allows relatively precise conclusions to be drawn about the number of preforms still in the storage container.

According to a further idea of the invention, an optical sensor can be provided to determine the filling status in the filling container. This is also preferably a light barrier or a camera with image processing.

According to a further idea of the invention, a sensor for determining a weight of the filling container can be provided to determine the filling state in the filling container. The number of preforms in the filling container can also be determined relatively precisely in this way.

According to a further idea of the invention, the filling container can also be provided and suitable as a transport container. This makes it possible to fill the filling container or transport container outside the device and then transport it to the location of the device for decanting.

According to a further idea of the invention, a control can be provided, at least for evaluating the filling level in the storage container, the filling status in the filling container and for controlling the transfer device for automatically transferring the preforms from the filling container into the storage container. The control recognizes or determines whether the filling container is full or empty, the fill level in the storage container falls below one of the limit values and controls the decanting device. The controller preferably also controls the signaling device.

The invention also relates to a system according to claim 27, namely with a device according to the invention. The latter is then part of a larger system in which the preforms are stored, separated, thermally conditioned and then formed into containers by applying pressure with a fluid, in particular in a blow molding or stretch blow molding process or in the form-fill process.

The device and/or system are provided with an electronic control device which controls the transfer device, in particular individual, several or all of the processes listed below: the automatic emptying of the filling container into the storage container, monitoring the filling level in the storage container, determining the filling status in the filling container, etc Defined conditions control a signaling device to output a signal. The control device is provided with suitable software for this purpose.

• 1 bis 8 Füllbehälter und Vorratsbehälter im Zeitablauf mit unterschiedlichen Positionen des Füllbehälters,
• 9 eine schematische Darstellung einer Anlage zum Herstellen von Behältern in der Draufsicht,
• 10 bis 15 einen aufrechten Schnitt durch den Vorratsbehälter mit im Zeitverlauf unterschiedlichen Füllständen.

Further features of the invention emerge from the description and from the claims. Advantageous exemplary embodiments of the invention are explained in more detail below with reference to drawings. Show it:

• 1 to 8 Filling containers and storage containers over time with different positions of the filling container,
• 9 a schematic representation of a system for producing containers in a top view,
• 10 to 15 an upright section through the storage container with different filling levels over time.

Reference is first made to 9 . Shown schematically is a system 10 for producing plastic containers from preforms, namely in a blow molding or stretch blow molding process. The forming process takes place in molds held on the circumference of a rotating work wheel 11. Arrows show the path of the preforms through the system 10. The description of blow molding and stretch blow molding processes is given without restriction of generality. In the same way, the processes and sequences described below could be implemented in methods and devices in which a liquid forming fluid is used.

The individual preforms are removed from or conveyed away from a storage container 12 in a quasi-continuous conveying stream 13. In the area of a subsequent separating unit 14, the preforms are brought to a defined distance and transferred to a temperature control device 15. The latter is connected to a transfer conveyor 16, which feeds the preforms to the work wheel 11. In the molds of the work wheel 11, the preforms are formed into containers by the blow molding or stretch blow molding process and are finally conveyed out of the area of the work wheel 11 by a removal conveyor 17 and transferred to a discharge conveyor, not shown. Such a system is, for example, in the DE 10 2018 107 676 A1 shown (without storage container).

• Im Vorratsbehälter 12 werden die Vorformlinge als Schüttgut bereitgehalten. Bei der Abförderung im Förderstrom 13 werden die Vorformlinge vorzugsweise ausgerichtet. Für den ungestörten Ablauf der Anlage ist der ununterbrochene Förderstrom 13 von Bedeutung. Um dies sicherzustellen, wird der Vorratsbehälter 12 zyklisch aus einem Füllbehälter 18 mittels einer Umfüllvorrichtung 19 befüllt. Während der Vorratsbehälter 12 stationär ist, kann der Füllbehälter 18 stationär in der Umfüllvorrichtung 19 angeordnet oder als Transportbehälter von der Umfüllvorrichtung 19 aufnehmbar sein.

The filling of the storage container 12 is based on the following 1 to 8 explains:

• The preforms are kept ready as bulk material in the storage container 12. At the discharge The preforms are preferably aligned in the conveying stream 13. The uninterrupted flow 13 is important for the undisturbed operation of the system. To ensure this, the storage container 12 is filled cyclically from a filling container 18 using a transfer device 19. While the storage container 12 is stationary, the filling container 18 can be arranged stationary in the decanting device 19 or can be received as a transport container by the decanting device 19.

The storage container 12 is equipped with a monitoring device 20 with which a fill level in the storage container 12 can be determined. The monitoring device 20 is preferably an optical sensor or a light barrier, a camera with image processing or a scale for determining the weight of the storage container. It is important that the monitoring device 20 can not only distinguish between “filled” and “empty”. What is required is the detection of different filling levels in order to compare them with one or more limit values.

In a similar manner, a monitoring device 21 is provided on the transfer device 19, with which the contents or the presence of the filling container 18 can be detected. However, a distinction between “filled” and “empty” or “available” and “not available” is sufficient here. The monitoring device 21 can preferably be a button, a light barrier, a camera with image processing or a scale.

The decanting device 19 is controlled by an electronic control device 22, in particular depending on the values determined in the monitoring devices 20, 21. In addition, the control device 22 controls a signaling device 23 for outputting an optical or acoustic signal. Finally, the control device 22 can also be connected to conveyors of the flow 13, for example to control the drive or to detect a condition. Furthermore, the control device 22 can also be provided for controlling the other components of the system 10 or can be connected to a central control device for this purpose.

In the 1 to 8 Electrical lines 24, 25, 26, 27, 28 are shown between the control unit 22 and the system components 13, 19, 20, 21, 23 mentioned. Depending on the task of the relevant part of the system, information and/or instructions can be transmitted.

• Zum Zeitpunkt 1 gemäß 1 sind Vorratsbehälter 12 und Füllbehälter 18 mit Vorformlingen gefüllt, siehe Füllstand 29 und Befüllungszustand 30. Mit dem Förderstrom 13 werden die Vorformlinge quasi-kontinuierlich aus dem Vorratsbehälter 12 entnommen. Entsprechend verringert sich der Füllstand 29 kontinuierlich.

The following process occurs when the system is operating properly:

• At time 1 according to 1 storage container 12 and filling container 18 are filled with preforms, see filling level 29 and filling state 30. With the conveying flow 13, the preforms are removed from the storage container 12 quasi-continuously. Accordingly, the fill level 29 decreases continuously.

At time 2 according to 2 Most of the preforms have been removed from the storage container 12, so that the fill level 29 has fallen to a first limit value 31. The filling container 18 is still full.

Due to the first limit value 31 reached in the storage container 12, the control device 22 controls the transfer device 19 to empty the filling container 18, so that the contents of the filling container 18 are emptied into the storage container 12 and the highest filling level 29 is briefly reached again, see point in time 3 3 . The preforms are removed from the storage container 12 during the entire time.

At time 4 according to 4 is the filling container 18 from the tilted transfer position 3 moved back to its upright starting position and remains empty until further notice, while the fill level 29 in the storage container 12 drops. After moving the filling container 18 back to the starting position, or beforehand when emptying the filling container 18, the control device 22 receives a specific signal B from the monitoring device 21. The signal B is interpreted by the control device 22 as “filling container empty” and is deleted in the control device 22 any other signal that may still be present.

At time 5 according to 5 the fill level 29 in the storage container 12 has fallen to a second limit value 32, which here is above the first limit value 31. The control device 22 then controls the signaling device 23 to output a filling signal. The filling container 18 is then filled by the operating personnel or the empty filling container 18 is exchanged for a full filling container. After replacing the filling container 18 or after filling it, the control device 22 receives a specific signal A from the monitoring device 21. The signal A is interpreted by the control device 22 as “filling container full” and deletes any other signal that may still be present in the control device 22.

A full filling container 18 is then available in the starting position, while the storage container 12 is almost empty, see point in time 6 6 with fill level 29, which here reaches the limit value 31 rather by chance but can also be below or above it.

So that the storage container 12 is not completely emptied, the filling container 18 is immediately emptied into the storage container 12 by means of the transfer device 19, see point in time 7 7 . The control unit 22 again receives the signal B “filling container empty”. The storage container 12 briefly reaches its highest level 29, as in 1 and 3 .

Finally, the filling container 18 is filled again or replaced with a full filling container, see point 8 according to 8th . The control unit 22 again receives the signal A “filling container full”. The storage container 12 is still almost full and continues to empty.

In the further course the phases of 2 to 8 run through again or several times.

The sequence of phases from time 5 to time 8 is particularly important. These phases follow one another immediately and without waiting time. During these phases, the filling container 18 is filled twice or exchanged for a full filling container, although the filling container 18 is only emptied into the storage container 12 once in the sequence of times 5 to 8. The other or, depending on the perspective, the first or second emptying takes place after time 2, namely after the fill level 29 in the storage container 12 has reached its first limit value 31.

With the method or device shown, the effort associated with handling the filling container 18 can be reduced. At least the breaks between handling the filling container 18 are significantly longer.

The two limit values 31, 32 can theoretically also correspond. Preferably, the second limit value 32 is above the first limit value 31 so that there is a time buffer for filling the filling container 18, because after reaching the second limit value 32 and before filling the storage container 12, the filling container 18 must first be filled or replaced.

What is important in this context is the function of the control device 22. After the second limit value 32 in the storage container 12 is undershot, this recognizes the refilling and replacement of the filling container 18, controls the emptying of the filling container 18 into the storage container 12 and expects the subsequent filling or replacement to occur as soon as possible of the filling container 18. As mentioned at the beginning, the filling state of the filling container 18 is monitored by the monitoring device 21. If the control unit 22 determines that the filling container 18 has not been refilled or replaced within a short, defined period of time, a signal is output via the signaling device 23. Such a short period of time is, for example, in the minute range.

In other words: The storage container 12 is cyclically filled with preforms, while the preforms are continuously removed in the conveying stream 13. In contrast, the filling container 18 is only emptied in one period and filled, emptied and filled again in another period. The cycles of filling the filling container 18 therefore differ from the cycles of emptying the filling container 18 or filling the storage container 12.

Detecting the fill level 29 in the storage container 12 by weighing it also enables an exact determination of the preforms that still need to be filled in at the end of production. The number of fully formed containers delivered from the work wheel 11 is already known because the machines used generally record this. The number of preforms located in front of the work wheel 11, i.e. in the conveying stream 13 up to the transfer conveyor 16, as well as the number of preforms that may have been discharged are generally also known. From this, the number of preforms that still need to be poured for a total production quantity of containers required can be calculated. Accordingly, the filling container 18 is only filled with the required amount of preforms.

Alternatively, only the required amount of preforms is filled from the filling container 18 into the storage container 12. This can be controlled by weighing the storage container 12 in conjunction with a signal or by automatically pivoting the filling container 18 back. For example, an optical traffic light display can be provided, which indicates when the storage container 12 has reached the required filling level and no further filling is required more should be done. Finally, the weighing of the storage container 12 can be replaced by a light barrier. The measurement is then just less precise.

Based on 10 to 15 An example of the method according to the invention is explained below with a representation of the fill level 29 in the storage container 12. The fill level 29 refers to the preforms present as filling material in the storage container 12.

Shown is an upright section through the storage container 12. The latter is open at the top and has a gap on its underside that cannot be seen in this view, parallel to a discharge conveyor 33 arranged underneath, with which the filling material can be conveyed from right to left, up to one Transfer area 34. The preforms are there from the conveyor 33 to the in the 10 to 15 conveyor 13, not shown.

Within the storage container 12, a roof-shaped guide profile 35 is arranged at a distance from the discharge conveyor 33, which extends from an end face 36 to the end face 37 on the transfer side. The guide profile 35 prevents the entire load of the preforms present in the storage container 12 from acting on the discharge conveyor 33. The preforms can only slide onto the discharge conveyor 33 from a lateral direction, i.e. perpendicular to the conveying direction 38 onto the discharge conveyor 33. For this purpose, the storage container 12 also has a bottom 39 that is inclined towards the discharge conveyor 33.

While in the 1 to 8 the monitoring device 20 is shown rather abstractly, are in the 10 to 15 More concrete measures are shown, namely a first light barrier 40 above the guide profile 35 and parallel to the conveying direction 38. The light barrier 40 defines a line-shaped area 41 of the monitoring.

In addition, a second light barrier 42 is arranged above, at a distance from the first light barrier 40 and perpendicular to it. The second light barrier 42 defines a line-shaped area 43 which extends perpendicular to the image plane, i.e. runs approximately in the horizontal direction and therefore in the 10 to 15 is only shown as a point.

The two light barriers 40, 42 form the in the exemplary embodiment 10 to 15 those in the 1 to 8 monitoring device 20 shown or are at least part of it. With the two light barriers 40, 42, the two limit values 31, 32 for the fill level 29 are monitored or the reaching of the two limit values 31, 32 is detected.

In 10 the storage container 12 is half full, in 11 almost complete. The level 29 in 11 corresponds approximately 1 .

During the ongoing production process, the preforms gradually slide onto the discharge conveyor 33 and are conveyed away in the conveying direction 38 from right to left. As a result, the fill level 29 decreases asymmetrically, primarily on the right side near the end face 36, see 12 . The filling level 29 drops below the level of the second light barrier 42.

At this point it is still assumed that the filling container 18 is filled. The control device 22 controls the transfer device 19 and the contents of the filling container 18 are emptied into the storage container 12, so that the filling level 29 is set above the second light barrier 42, as in 13 recognizable and analogous to 3 . The filling container 18 remains empty, as in 4 shown.

As the process progresses, the fill level 29 in the storage container 12 drops again below the second light barrier 42, see 14 . The control device 22 then controls the signaling device 23 and a signal is output there, see 5 . An operator fills the filling container 18 or replaces the empty filling container 18 with a full filling container. At the same time, the fill level 29 continues to drop until it reaches or below the first light barrier 40, see 15 and as well 6 .

The control device 22 recognizes the full filling container 18 and controls the transfer device 19. The filling container 18 is emptied into the storage container 12, so that the filling level 29 again 10 or even according to 11 sets. The filling container 18 is then filled again or replaced by operating personnel. The control device 22 again detects the full filling container 18. If the filling level 29 then falls below the second light barrier 42 again, the filling container 18 can be automatically emptied into the storage container 12 by the transfer device 19, without intervention by the operating personnel.

When filling the storage container 12 in the transition from 15 to 10 and 11 , it may also be useful or necessary to fill or replace the filling container 18 a total of three times, depending on the capacity. After the first filling or replacement and emptying into the storage container 12, the fill level 29 results 10 . After the second emptying or replacement and filling of the storage container 12, the filling level is 29 in 11 and with the third filling or replacement of the filling container 18, the latter is in the waiting position for the interim filling according to the transition from 12 to 13 .

Reference symbols

10

Attachment

11

work bike

12

storage container

13

Sponsor

14

Separation unit

15

Temperature control device

16

Transfer conveyor

17

removal conveyor

18

Filling container (transport container)

19

Transfer device

20

Monitoring device (storage container)

21

Monitoring device (filling container)

22

Control unit

23

Signaling device

24

Signaling device

25

electrical line

26

electrical line

27

electrical line

28

electrical line

29

Filling level of the storage container

30

Filling status of the filling container

31

first limit

32

second limit

33

conveyor

34

Handover area

35

Lead profile

36

front side

37

front side

38

Direction of conveyance

39

inclined floor

40

first light barrier

41

linear area

42

second light barrier

43

linear area

Claims (27)

Method for providing and feeding preforms to a device for the production of containers by forming the preforms by pressurizing them with a fluid, comprising: a) placing the preforms in a filling container (18) in a transfer device (19) for transferring the preforms into one Storage container (12), b) monitoring a fill level (29) in the storage container (12), c) automatically emptying the filling container (18) into the storage container (12) when the fill level (29) in the storage container (12) reaches a first limit value ( 31), d) removal of the preforms from the storage container (12) in a conveying stream, characterized in that a second limit value (32) of the fill level (29) is monitored on the storage container (12), the second limit value (32) being greater or is equal to the first limit value (31), that a filling state (30) is determined at the filling container (18), and that if the second limit value (32) in the storage container (12) is undershot, the filling state (30) in the filling container (18) is evaluated to control filling of the filling container (18) or replacing it with a filled filling container (18). Procedure according to Claim 1 , characterized in that if the storage container (12) falls below the second limit value (32) and at the same time the filling container (18) is empty, the filling container (18) is filled or is replaced by a filled filling container (18), the filled filling container (18) automatically is emptied into the storage container (12), and the now empty filling container (18) is filled or replaced by a filled filling container (18) without waiting for the fill level to fall below one of the limit values (31, 32). Procedure according to Claim 1 or 2 , characterized in that a signal is generated at least when a) the fill level in the storage container (12) falls below the second limit value (32) and at the same time the filling container (18) is empty, or b) the filling or replacement of the container is automatically filled Storage container (12) emptied filling container (18) does not take place within a defined period of time. Procedure according to Claim 3 , characterized in that the signal is an optical or acoustic signal. Procedure according to one of the Claims 1 until 4 , characterized in that the filling container (18) is used as a transport container and that filled transport containers are fed to the decanting device (19) and emptied transport containers are removed. Procedure according to one of the Claims 1 until 5 , characterized in that the fill level in the storage container (12) is determined by one or more light barrier measurements on the storage container (12). Procedure according to one of the Claims 1 until 6 , characterized in that the limit values (31, 32) are monitored by optical sensors (40, 42). Procedure according to one of the Claim 7 , characterized in that the optical sensors (40, 42) monitor at least two linear areas (41, 43) in the storage container (12), which lie at a distance one above the other and in particular run transversely to one another. Procedure according to one of the Claims 1 until 5 , characterized in that the fill level in the storage container (12) is determined by a weight measurement on the storage container (12). Procedure according to one of the Claims 1 until 9 , characterized in that for the filling status of the filling container (18) a distinction is only made between “full” and “empty”. Procedure according to one of the Claims 1 until 10 , characterized in that a “full” filling state is determined for the filling container (18) by determining or detecting insertion of the filling container (18) into the transfer device (19). Procedure according to one of the Claims 1 until 11 , characterized in that an “empty” filling state is determined for the filling container (18) by - a tilting process of the filling container (18), - leaving a starting position of the filling container (18), - a movement of the filling container (18) from the Starting position into a transfer position, - reaching the transfer position, - leaving the transfer position, - a return movement to the starting position or - reaching the starting position can be determined or detected. Method for producing containers by providing preforms, feeding the preforms in a conveying stream, thermally conditioning the preforms and then forming them into containers by pressurizing them with a fluid, characterized by a method for providing and feeding the preforms according to one of Claims 1 until 12 . Device for providing preforms for a device for producing containers by forming the preforms by pressurizing them with a fluid, comprising: a) a storage container (12) from which the preforms can be removed in a conveying stream, b) a first monitoring device (20) for monitoring a fill level (29) of preforms in the storage container (12), c) a filling container (18) in which the preforms are placed, d) a transfer device (19) for automatically transferring the preforms from the filling container (18) into the Storage container (12) depending on a first limit value (31) of the fill level (29) in the storage container (12), characterized by a second monitoring device (21) for determining a filling state in the filling container (18), the first monitoring device (20) for Monitoring of the first limit value (31) and a second limit value (32) of the fill level (29) is provided. Device according to Claim 14 , characterized by a signaling device (23) with which a signal can be output at least when a) the fill level (29) in the storage container (12) falls below the second limit value (32) and at the same time the filling container (18) is empty, or b ) the filling container (18), which is automatically emptied into the storage container (12), is not filled or replaced within a defined period of time. Device according to Claim 15 , characterized in that the signaling device (23) outputs an optical or acoustic signal. Device according to one of the Claims 14 until 16 , characterized in that the first monitoring device (20) contains at least one optical sensor. Device according to one of the Claims 14 until 17 , characterized in that the monitoring device (20) has a first sensor (40) for monitoring the first limit value (31) and a second sensor (42) for monitoring the second limit value (32). Device according to Claim 18 , characterized in that the particularly optical sensors (40, 42) monitor at least a first line-shaped area (41) for the first limit value (31) and a second line-shaped area (43) for the second limit value (32). Device according to Claim 19 , characterized in that the two linear areas (41, 43) run transversely to one another. Device according to Claim 19 or 20 , characterized in that the first linear region (41) runs in the direction (38) of the flow. Device according to one of the Claims 14 until 21 , characterized in that the first monitoring device (20) contains at least one sensor for determining a weight of the storage container (12). Device according to one of the Claims 14 until 22 , characterized in that an optical sensor is provided to determine the filling status in the filling container (18). Device according to one of the Claims 14 until 22 , characterized in that to determine the filling status in the filling container (18) a sensor is provided for determining a weight of the filling container (18). Device according to one of the Claims 14 until 24 , characterized in that the filling container (18) is also provided and suitable as a transport container. Device according to one of the Claims 14 until 25 , characterized by a control (22) at least for evaluating the fill level (29) in the storage container (12), the filling status (30) in the filling container (18) and for controlling the transfer device for automatically transferring the preforms from the filling container (18) into the Storage container (12). Plant (10) for producing containers by providing preforms, feeding the preforms in a conveying stream (13), thermally conditioning the preforms and then forming them into containers by pressurizing them with a fluid, characterized by a device according to one of the Claims 14 until 26 .

Images