Method and device for producing containers filled with liquid filling material from heat-treated preforms

Abstract

A method for producing a container filled with a liquid filler from a heat-treated preform, wherein the filler is introduced into the preform under pressure through a filling valve at a molding and filling station, wherein the filler is provided by a filler source and is pumped into the preform by a positive displacement pump arranged between the filler source and the molding and filling station when the filling valve is open, wherein at least two molding and filling stations (11, 12, 13, 14, 32, 33) are assigned to each positive displacement pump (23, 24, 36), and the filler is supplied to the at least two molding and filling stations by the positive displacement pump (23, 24, 36), in particular in sequence.

Description

Technical Field

[0001] The invention relates to a method and a device for producing containers filled with a liquid filling material from heat-treated preforms. Background Art

[0002] Methods and devices of this type are used in container forming and filling plants. In such plants, a heat-treated preform is expanded into the desired container shape and the formed container is filled by simultaneously introducing a liquid filler under high pressure at a forming and filling station. During the forming and filling process, the preform is arranged in a mold of the forming and filling station, which mold predetermines the final desired container shape.

[0003] The thermal treatment of the preform takes place, for example, in a heating tunnel or heating zone, as described, for example, in document WO 2012 / 083910 A1.

[0004] Such a molding and filling device is known in the prior art. For this purpose, reference is made to document DE 10 2010 007541A1.

[0005] The forming and filling device is intended to replace conventional devices in which a separate blow-molding station and a separate filling station are provided, in which the heat-treated parisons are first shaped in two steps in the blow-molding station by introducing gas under high pressure into a finished container, which is filled in the next step in the filling station.

[0006] In the molding and filling devices mentioned here, molding and filling are achieved in one step. As mentioned above, for this purpose, the filler is introduced into the preform under high pressure at the desired metering rate and the desired number of cycles. Typical filling times are in the range of 100-150 milliseconds, which requires a volume flow of up to 20 liters / second and a pressure of up to 40 bar.

[0007] In view of these requirements, in known molding and filling plants, for example, devices of this type are provided which are intended to enable the required pressures and volume flows to be achieved.

[0008] The filler material is provided by a filler material source, usually a filler material reservoir, which is connected via an inlet line to a filling valve which controls the inflow to the parison.

[0009] The charge reservoir is usually a pressure reservoir which is acted upon by a pressure pump and which delivers the charge at a defined pressure into the supply line.

[0010] In the known device, a positive displacement pump is also provided between the filling source and the filling valve. The filling source is fluidically connected to the positive displacement pump via a first inlet-side section of the feed line, which in turn is connected to the filling valve via a second outlet-side section of the feed line.

[0011] The positive displacement pump is used, in particular, to provide the required pressure and volume flow, so that the filler material can be delivered via the second section of the supply line into the preform or into the formed container when the filling valve is open.

[0012] In this type of method and device, it is provided that a positive displacement pump is assigned to each molding and filling station. This constitutes a relatively high structural cost and is also maintenance-intensive. Such prior art is shown in documents WO 2018 / 141347 A1 and DE 10 2018 106 930 A1. Summary of the invention

[0013] The object of the present invention is to provide a method by which the effort can be reduced. Another object is to provide a device which requires less installation space and can be operated more cost-effectively.

[0014] These objects are achieved by a method having the features of the invention and by a device having the features of the invention.

[0015] As is known from the prior art, the method according to the invention operates with a filler source which provides the desired filler quantity.

[0016] A filler source is fluidly connected to the forming and filling station.

[0017] Furthermore, a positive displacement pump is provided between the filler source and the forming and filling station, which generates the pressure and volume flow required when filling and forming the parison or the required different volume flows. Usually, the filling and forming of the parison is not carried out with a constant volume flow. Often, a smaller volume flow, for example 2 liters / second, is first applied; then a higher volume flow, for example 5 liters / second, is applied; and finally a low volume flow, for example 2 liters / second, is applied again. This is only an example value. Depending on the material and volume of the parison, other volume flow characteristics with, for example, a suction speed of up to 20 liters / second can also be applied. These other volume flow characteristics can be easily realized by corresponding control of the positive displacement pump.

[0018] The term filler source can be interpreted broadly. A filler source can be, for example, a dispensing station on a device for producing fillers. If the device is located, for example, in another location, a filler reservoir is usually used as a source.

[0019] Delivery of filler from the filler source may be achieved without pressure or under pressure.

[0020] In the case of no pressure output, the volumetric pump must be designed so that it can draw the filler. Alternatively, it is also conceivable that another pump is provided in the feed line, with which the filler can be drawn from a filler source to the volumetric pump.

[0021] Preferably, a filling source is provided which discharges the filling material under pressure. This can be, for example, a filling pressure reservoir which is supplied with filling material under pressure, for example by a continuously operating pump. The use of a filling source which discharges the filling material under pressure has hydraulic advantages and allows, for example, a smaller design of a positive displacement pump.

[0022] According to the invention, it is now provided that each positive displacement pump is assigned at least two molding and filling stations at which the positive displacement pump can pump filler material into the preforms.

[0023] The pumping process can be seen as follows: First, the pump is started and the filling valve of the associated forming and filling station is opened. Subsequently, the pump applies the charge to the parison with the desired volume flow characteristics and pressure, and after the forming and filling process is completed, the filling valve is closed again and the pump is stopped. This process shall also be referred to as "feeding" hereinafter.

[0024] It is conceivable that the volumetric pump supplies the at least two associated forming and filling stations in parallel or overlapping in time. For this purpose, it is sufficient to adapt the filling quantity to the suction power of the volumetric pump accordingly. Naturally, in industrial processes, the forming and filling stations of the device are supplied with heat-treated preforms in sequence and are further processed as soon as possible in order to prevent the preforms from cooling too much before forming.

[0025] This may be a cyclically operated machine or preferably also a machine according to the circular rotor principle, in which the forming and filling stations are arranged on an annular running wheel. In any case, in such a process, two preforms are not available for filling and forming at the same time interval. The parallel filling of these two preforms, which are staggered by at least one cycle or staggered in time, with coordinated volume flow characteristics and with pumps is therefore problematic in industrial processes. Only filling with constant volume flow that overlaps in time is possible.

[0026] It is therefore preferably provided that the positive displacement pump supplies the molding and filling stations assigned to it in sequence.

[0027] It is also preferably provided that a plurality of positive displacement pumps are provided, which supply a plurality of forming and filling stations in a defined sequence. In this design, it is provided that between a forming and filling station supplied by a positive displacement pump there is at least one forming and filling station supplied by another positive displacement pump. In this way, a higher number of cycles or a higher rotation speed can be achieved in an apparatus with a running wheel. For example, it is conceivable that a positive displacement pump supplies successively each of the first forming and filling stations assigned to it, and then accordingly supplies at least one further configured forming and filling station. In the last-mentioned design, then a temporally overlapping filling of the parisons is also possible.

[0028] If, as an example, a working wheel with a cycle time of 1800 milliseconds is taken, on which the forming and filling stations are arranged, then 6 stations can be supplied in succession using a pump which requires 300 milliseconds for a forming and filling process. 12 stations can be supplied using 2 pumps which each supply successive stations alternately, 18 stations can be supplied using 3 pumps, and so on.

[0029] Furthermore, the invention relates to a device for producing containers to be filled with a liquid filling material.

[0030] As is known from the prior art, in this device, filler is delivered from a filler source into an inlet line to a filling valve of a molding and filling station. A positive displacement pump is provided between the filler source and the molding and filling station, which is connected to the filler source via a section of the inlet side of the inlet line and to the filling valve of the molding and filling station via a section of the outlet side of the inlet line. The positive displacement pump is designed in such a way that it can pump the filler provided by the filler source into the preform with the desired volume flow characteristics and pressure.

[0031] With regard to the designation of the term “fill source”, reference is made to the above-described embodiments. In addition, it should also be mentioned that the fill source, for example a reservoir or a pressure reservoir, can be part of the device, but can also be provided separately, ie externally thereto.

[0032] According to the invention, it is provided that the positive displacement pump is fluidically connected to at least two molding and filling stations and is controlled and designed in such a way that it supplies the stations with the required filler quantity, in particular successively, at the desired rate.

[0033] Compared to devices known from the prior art, in which a positive displacement pump is assigned to each molding and filling station, the device according to the invention achieves considerable structural savings.

[0034] It is conceivable that the positive displacement pump is a reciprocating piston pump which each performs a partial stroke for supplying the configured forming and filling stations. A disadvantage of reciprocating piston pumps is that they first have to be filled with a filling quantity and then discharge this filling quantity in a second step. The filling of the piston pump takes place via a pressure boost valve, which makes the design relatively expensive and slow.

[0035] Preferably, therefore, a rotary pump is provided as a positive displacement pump, which has, for example, pistons or gears operating in an interlocking manner, in particular a screw pump, a circulating pump or a rotary piston pump. A rotary pump does not require a pressure boost valve and can usually be cleaned without residue by means of flushing or the like. This makes CIP cleaning (cleaning in place) possible. In addition, a rotary pump can be easily conveyed forwards and backwards, which can be used, for example, after the forming and filling process to set the desired filling level in the container with a pressureless liquid source.

[0036] To supply the forming and filling stations, it is only necessary to switch on the pump and to generate the desired volume flow characteristics by setting, for example, a defined rotational speed of the intermeshing circles or of the rotary pistons.

[0037] Suitable pumps are known in the prior art and are available on the market in a number of different variants.

[0038] As known from the prior art, in the device according to the present invention, the molding and filling station is preferably arranged on the rotating working wheel. The volumetric pump can also be arranged on the working wheel. But it is also conceivable that the volumetric pump is arranged outside the working wheel and is connected to the working wheel and the molding and filling station arranged thereon through a swivel joint. This also applies to one or more filling material storage devices or filling material pressure storage devices. Moreover, the filling material storage device can be arranged outside the working wheel or be arranged to rotate with it. In addition, a filling material source can be configured for each volumetric pump. But it is also conceivable that a filling material source, for example a filling material pressure storage device with a corresponding design, is connected to a plurality of volumetric pumps. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention will be further explained below with reference to two drawings. In the drawings:

[0040] Figure 1 : illustrates an embodiment of the apparatus and method of the present invention; and

[0041] Figure 2 : Another embodiment is shown. DETAILED DESCRIPTION

[0042] Figure 1A device 10 is shown in which four forming and filling stations 11, 12, 13 and 14 are arranged on a running wheel 15, which rotates in the direction of the arrow. Usually, a plurality of forming and filling stations, for example 12, are arranged on a running wheel. For reasons of clarity, it is reduced to four stations. A heat-treated parison 28 is transferred to the running wheel or the forming and filling station arranged on the running wheel by a device not shown in a position. In the case shown, for example, it is the position where the forming and filling station 11 is located. The parison 28 is then formed into a container and filled (not shown) in the continued rotation of the running wheel 15, and the finished, filled container is transferred to another processing mechanism, such as a capping machine or a labeling machine, at the position where the forming and filling station 14 is located, for example.

[0043] Each of the forming and filling stations 11-14 has a filling valve 16 and a mold 17, which predetermines the final shape of the parison to be filled and formed. A filling pressure reservoir 20 is provided outside the running wheel 15, and the filling pressure reservoir is filled by a pump (not shown). As mentioned above, the filling pressure reservoir constitutes a preferred design of the filling source. However, other filling sources are of course also conceivable.

[0044] Filling pressure accumulator 20 is fluidically connected via inlet-side sections 21 and 22 of the inlet line to positive displacement pumps 23 and 24. Pumps 23 and 24 are in turn fluidically connected to molding and filling stations 11-14 via outlet-side sections 25 and 26 of the inlet line.

[0045] In the case shown, a positive displacement pump 23 is assigned to the forming and filling stations 12 and 14, while a positive displacement pump 24 supplies the forming and filling stations 11 and 13. The forming and filling station 11 is first supplied by the pump 24. With further rotation of the impeller 15, a new parison 28 is then placed in the forming and filling station 14 and this parison 28 is filled with another positive displacement pump 23. In the next step, the forming and filling station 13 follows, which is in turn supplied by the pump 24, and so on.

[0046] It goes without saying that, as mentioned above, additional forming and filling stations, for example 12, can be arranged on the impeller. At least two of these 12 forming and filling stations, but also more stations, can each be supplied by a positive displacement pump. For example, it is conceivable that in an impeller with 12 positions, four pumps are provided, each of which supplies three forming and filling stations. Supplying subsequent forming and filling stations by different positive displacement pumps has the advantage that a faster number of cycles or a rotation speed of the impeller can be achieved.

[0047] As mentioned above, in the case shown, the filler is provided under pressure via the pressure reservoir 20, while the positive displacement pumps 23 and 24 provide the required volume flow and pressure during the filling and forming of the parison. Volume flows of up to 20 liters / second are conceivable, for example. Usually, the volume flow changes during the filling. It is conceivable, for example, to start with a lower volume flow, then increase the volume flow, and reduce the volume flow again when the filling is almost finished. Of course, it is also conceivable to set other volume flow characteristics. This is basically related to the material of the parison, etc.

[0048] Figure 2 Basically, it shows Figure 1 A similar device 30.

[0049] Once again, the running wheel 31 can be seen, on which the forming and filling stations 32 and 33 are arranged. The preforms 28 are placed in the forming and filling station 32. Furthermore, a filling pressure accumulator 34 is provided here, which provides the filling material under pressure. The filling pressure accumulator 34 is connected to a positive displacement pump 36 via a section on the input side of an input line 35. The positive displacement pump 36 is itself connected to the filling stations 32 and 33 via a section 37 on the output side. Figure 1 The difference of the device shown in FIG. 3 is that the pressure accumulator 34 and the displacement pump 36 are arranged on the impeller 31 in a rotationally driven manner. The advantage is that the distance between the displacement pump and the filling valve is relatively short. On the other hand, it is also conceivable that the weight of the impeller 31 is increased by arranging components on the impeller 31, which may have structural disadvantages.

Claims

1. A method for producing a container filled with a liquid filler from a heat-treated parison, the method comprising: introducing a liquid filler under pressure into a first preform at a first forming and filling station through a first filling valve while the first filling valve is open; Subsequently, a liquid filler is introduced under pressure into the second preform at a second forming and filling station through a second filling valve while the second filling valve is open; wherein filler is provided by a filler source, wherein filler is pumped into the first parison by a first positive displacement pump, wherein, in turn, filler is pumped into the second parison by the same first positive displacement pump that previously pumped filler into the first parison, and Wherein, the first positive displacement pump is arranged between the filler source and the first forming and filling station and the second forming and filling station.

2. The method according to claim 1, characterized in that The filler source is a filler reservoir.

3. The method according to claim 1, characterized in that A plurality of positive displacement pumps (23, 24) are provided which supply a plurality of forming and filling stations (11, 12, 13, 14) in a defined sequence, wherein between the forming and filling stations (12, 14) supplied by one positive displacement pump (23) there is at least one forming and filling station (13) supplied by another positive displacement pump (24).

4. The method according to claim 3, characterized in that The positive displacement pumps (23, 24) successively supply each first forming and filling station (11, 14) assigned to them and subsequently supply at least one further, assigned forming and filling station (13, 12).

5. The method according to any one of claims 1 to 4, characterized in that The forming and filling stations (11, 12, 13, 14, 32, 33) are supplied with filler material in a temporally overlapping manner.

6. The method according to any one of claims 1 to 4, characterized in that The forming and filling stations (11, 12, 13, 14, 32, 33) are arranged on running wheels (15, 31).

7. The method according to claim 1, characterized in that The fill source is a fill pressure reservoir (20, 34).

8. An apparatus for producing a container filled with a liquid filler from a heat-treated parison, the apparatus comprising: a first forming and filling station and a second forming and filling station; A filler source connected via a feed line to the corresponding filling valves of the first forming and filling station and the second forming and filling station; a positive displacement pump which is connected to the filler source via a section of the feed line on the feed side and to the corresponding filling valves of the first and second forming and filling stations via a section of the feed line on the feed side; wherein the positive displacement pump is designed such that it delivers the liquid filler into the outlet-side section of the supply line with the pressure and volume flow characteristics required for shaping the heat-treated preform into a container filled with the liquid filler, and The positive displacement pump is designed to supply liquid filler to the first forming and filling station and in turn to the second forming and filling station.

9. The device according to claim 8, characterized in that The filler source is a filler reservoir.

10. The device according to claim 8, characterized in that The positive displacement pumps (23, 24, 36) are rotary pumps.

11. The device according to any one of claims 8 to 10, characterized in that Each positive displacement pump (36) is provided with a fill source.

12. The device according to any one of claims 8 to 10, characterized in that The forming and filling stations (11, 12, 13, 14, 32, 33) are arranged on rotating working wheels (15, 31).

13. The device according to claim 12, characterized in that The positive displacement pump (23, 24) and / or the filler source are not arranged on the impeller.

14. The device according to claim 8, characterized in that The fill source is a fill pressure reservoir (20, 34).

15. The device according to claim 8, characterized in that The positive displacement pump (23, 24, 36) is a screw pump, a circulation pump or a rotary piston pump.

16. The device according to claim 11, characterized in that The fill source is a fill pressure reservoir (34).

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