U.S. patent application number 14/065153 was filed with the patent office on 2014-02-27 for blow moulding machine with arrangement for cleaning the blow mould.
This patent application is currently assigned to KRONES AG. The applicant listed for this patent is KRONES AG. Invention is credited to Jochen Hirdina.
Application Number | 20140054812 14/065153 |
Document ID | / |
Family ID | 43014194 |
Filed Date | 2014-02-27 |
United States Patent
Application |
20140054812 |
Kind Code |
A1 |
Hirdina; Jochen |
February 27, 2014 |
BLOW MOULDING MACHINE WITH ARRANGEMENT FOR CLEANING THE BLOW
MOULD
Abstract
An apparatus for transforming plastic preforms into containers,
includes at least one blow mould which forms a cavity, inside which
the plastic preforms can be transformed into containers. The
apparatus includes an opening and closing mechanism for opening and
closing the blow mould, and a cleaning device for cleaning regions
of the blow mould. The cleaning device includes at least a first
cleaning element for cleaning an inner wall of the blow mould,
which cleaning element is arranged at least at times outside the
blow mould.
Inventors: |
Hirdina; Jochen;
(Regensburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KRONES AG |
NEUTRAUBLING |
|
DE |
|
|
Assignee: |
KRONES AG
NEUTRAUBLING
DE
|
Family ID: |
43014194 |
Appl. No.: |
14/065153 |
Filed: |
October 28, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12853162 |
Aug 9, 2010 |
8580166 |
|
|
14065153 |
|
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Current U.S.
Class: |
264/39 ; 425/226;
425/229 |
Current CPC
Class: |
B08B 9/00 20130101; B29C
2049/4694 20130101; B29C 49/06 20130101; B29L 2031/7158 20130101;
B29C 49/4273 20130101; B29C 49/36 20130101; B29C 33/72 20130101;
B29C 49/42 20130101; B29C 49/12 20130101 |
Class at
Publication: |
264/39 ; 425/229;
425/226 |
International
Class: |
B29C 49/42 20060101
B29C049/42 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 11, 2009 |
DE |
10 2009 036 920.1 |
Claims
1-14. (canceled)
15. An apparatus for transforming plastic preforms into containers,
comprising at least one blow mould which forms a cavity, inside
which the plastic preforms can be transformed into containers,
comprising a pressure application device for applying a medium to
the plastic preforms in order to expand the latter against an inner
wall of the blow mould delimiting the cavity, comprising a
stretching rod for stretching the plastic preforms in the
longitudinal direction (L) thereof, and comprising an opening and
closing mechanism for opening and closing the blow mould, wherein
the apparatus comprises a cleaning device for cleaning regions of
the blow mould, wherein the cleaning device comprises at least a
first cleaning element for cleaning the inner wall of the blow
mould, and this cleaning element is arranged at least at times
outside the blow mould and is movable by a robotic arm.
16. The apparatus according to claim 15, wherein the apparatus
comprises a transport device which transports the blow moulds along
a predefined transport path.
17. The apparatus according to claim 15, wherein the blow mould is
arranged such as to be movable relative to the cleaning device.
18. The apparatus according to claim 15, wherein at least one
cleaning element is a cleaning nozzle which applies a liquid
cleaning medium to the inner wall.
19. The apparatus according to claim 15, wherein the cleaning
device comprises a mechanical cleaning element which can be brought
into contact with the inner wall.
20. The apparatus according to claim 18, wherein the mechanical
cleaning element is arranged after the cleaning nozzle in the
transport direction of the blow moulds.
21. The apparatus according to claim 20, wherein the second
cleaning element is spaced apart from the cleaning nozzle in the
transport direction of the blow moulds.
22. The apparatus according to claim 15, wherein the apparatus
comprises a rotatable carrier, on which a plurality of blow moulds
are arranged.
23. The apparatus according to claim 15, wherein the apparatus
comprises a rinsing device for rinsing the blow moulds.
24. A method for transforming plastic preforms into plastic
containers, wherein the plastic preforms are expanded inside a
cavity through the application of a medium to form plastic
preforms, and wherein this cavity (is formed by at least one inner
wall of a blow mould, and the blow mould can be transferred from an
open state to a closed state, wherein a cleaning mode is provided,
in which no plastic container is accommodated inside the blow mould
and at least one region of the blow mould is cleaned, wherein the
cleaning takes place in an open state of the blow mould and a first
cleaning element for cleaning the inner wall of the blow mould is
arranged at least at times outside the blow mould and is moved by a
robotic arm.
25. The method according to claim 24, wherein the blow mould is
opened and a liquid cleaning agent is applied to the inner wall in
the open state.
26. The method according to claim 24, wherein the inner wall is
cleaned by a mechanical cleaning element in an open state of the
blow mould.
27. The method according to claim 25, wherein the cleaning fluid is
left on the inner wall for a predefined period of time in order to
act thereon.
28. The method according to claim 10, wherein a rinsing mode is
provided, in which the inner wall is rinsed.
29. The apparatus according to claim 15, wherein the cleaning
element has a spray head which is movable by a robotic arm.
30. The apparatus according to claim 28, wherein the spray head is
guidable over the inner surface and is spraying the inner
surface.
31. The method according to claim 24, wherein the cleaning element
has a spray head which is moved by a robotic arm.
32. The method according to claim 31, wherein the spray head is
guided over the inner surface and sprays the inner surface.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. application Ser.
No. 12/853,162, filed Aug. 9, 2010, which is entirely incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to apparatuses for
transforming plastic preforms into plastic containers, and in
particular to blow moulding machines. Such blow moulding machines
have long been known from the prior art. They usually comprise a
blow mould, inside which the plastic preforms are expanded through
the application of pressure to form plastic containers. During this
stretch-blow moulding of plastic containers, so-called oligomers,
i.e. short-chain molecules or foreign substances, are excreted onto
the blow mould from the plastic of the plastic preforms. The
surface of these blow moulds therefore becomes dull and in the
extreme case rough as it becomes increasingly soiled. However, this
has negative effects on the bottle quality, since this may lead to
the situation whereby the bottle appearance may become cloudy on
account of the dull blow moulds or else the cooling on the mould
surface is reduced as a result of the roughness.
[0003] Since both of these problems are unacceptable, the blow
moulds must be cleaned and usually polished at regular intervals.
Particularly high degrees of soiling by oligomers occur when
working with high mould temperatures for process reasons (e.g. in
the case of hot fill processes), since soiling is much faster with
hot moulds and the cleaning of the moulds in the hot state can be
carried out only with a safety risk due to the risk of burning.
Particularly in the case of a so-called hot filling installation
with a blow moulding machine and a filler block, this cleaning of
the moulds is often a very negative aspect.
[0004] A container production apparatus and a production method for
moulded bodies are known from WO 2008 125216 A2. In this case, a
radiation device is arranged at or on the blow moulding machine,
the radiation being directed at least onto one region of the blow
moulding machine.
[0005] The object of the present invention is therefore to simplify
the cleaning of such blow moulding machines. The object of the
invention is also to provide an automated method for cleaning blow
moulds.
SUMMARY OF THE INVENTION
[0006] An apparatus according to the invention for transforming
plastic preforms into containers comprises at least one blow mould
which forms a cavity, inside which the plastic preforms can be
transformed into containers. The apparatus also comprises a
pressure application device for applying a medium to the plastic
preforms in order to expand the latter against an inner wall of the
blow mould delimiting the cavity. The apparatus advantageously also
comprises a stretching rod for stretching the plastic preforms in
the longitudinal direction thereof, and also an opening and closing
mechanism for opening and closing the blow mould. The apparatus
also comprises a cleaning device for cleaning regions of the blow
mould.
[0007] According to the invention, the cleaning device comprises at
least a first cleaning element for cleaning the inner wall of the
blow mould, and this cleaning element is arranged at least at times
outside the blow mould.
[0008] Advantageously, the cleaning device allows an automated
cleaning of the blow mould. For example, a special cleaning mode
may be provided, in which the blow mould or the inner wall thereof
is cleaned. However, the present invention is also applicable to
blow moulding machines which have no stretching rod.
[0009] It is therefore proposed according to the invention to use a
cleaning system and in particular a so-called CIP
(Cleaning-In-Place) cleaning system to clean the inner wall of the
blow mould. Particularly during the times in which the cleaning
element is not carrying out any cleaning, said cleaning element is
arranged outside the blow mould. The opening and closing mechanism
is advantageously also used to load a blow mould with new plastic
preforms and to remove blow-moulded containers from the blow
mould.
[0010] In one advantageous embodiment, the apparatus comprises a
transport device which transports the blow moulds along a
predefined transport path. Advantageously, a plurality of blow
moulds are arranged on a rotatable carrier and particularly
preferably on a circular carrier. This is preferably the same
carrier on which the blow moulds can also be arranged during normal
operation of the apparatus. The apparatus advantageously has a
cleaning mode for carrying out the cleaning of the blow moulds.
[0011] The blow moulds are advantageously arranged such as to be
movable relative to the cleaning device. To this end, it is
possible that the cleaning devices or cleaning elements are
arranged in a stationary manner along the transport path of the
blow moulds in the normal operating mode. However, it would also be
possible that the cleaning device together with the blow moulds is
arranged on a carrier and this carrier transports both the blow
moulds and the cleaning elements.
[0012] In a further advantageous embodiment, at least one cleaning
element is a cleaning nozzle which applies a liquid cleaning medium
to the inner wall.
[0013] Suitable cleaning agents are those substances which can be
used to clean (CIP cleaning) the outside and inside of machines and
installations in the beverage-bottling industry. Examples of such
cleaning agents are sodium hydroxide (NaOH), acidic cleaning agents
based on phosphoric acid, acidic cleaning agents based on nitric
acid, disinfecting agents based on acetic acid, ozone, hydrogen
peroxide, chloralkali cleaning agents, hot water or steam. In
addition, chlorine dioxide could also be used as the cleaning
agent.
[0014] In a further advantageous embodiment, the cleaning device
comprises a second, mechanical cleaning element which can be
brought into contact with the inner wall. This cleaning element may
be for example a brush device which is advantageously arranged such
as to be able to rotate. This second cleaning element is preferably
also arranged outside the blow mould in a closed state of the
latter. Advantageously, the first cleaning element can be
controlled independently of the second cleaning element. The first
cleaning element and the second cleaning element preferably act in
different ways on the inner wall of the blow mould.
[0015] In a further advantageous embodiment, the mechanical
cleaning element is arranged after the cleaning nozzle in the
transport direction of the blow moulds. It is thus possible that
the inner wall is first sprayed with the cleaning medium and then
cleaned and/or polished by the cleaning brush.
[0016] In a further advantageous embodiment, the cleaning element,
for example the brush, is spaced apart from the cleaning nozzle in
the transport direction of the blow moulds. In this way, in the
cleaning mode, a predefined period of time elapses between the
application of the cleaning medium to the inner wall and the
subsequent polishing with the brush, so that the cleaning medium is
left to act for a certain period of time. However, it would also be
possible that, for example while the blow mould is stationary,
firstly a cleaning nozzle and then a cleaning brush enters the blow
mould.
[0017] Preferably, transport devices are provided for moving the
cleaning nozzles or cleaning brushes. These may be transport
devices which move the nozzles or the brushes for example
perpendicular to the longitudinal direction of the blow mould.
However, it would also be possible that said elements are
introduced into the blow mould in the longitudinal direction of the
blow mould.
[0018] In a further advantageous embodiment, the apparatus
comprises a rotatable carrier, on which a plurality of blow moulds
are arranged.
[0019] Advantageously, the apparatus also comprises a rinsing
device for rinsing the blow moulds. This rinsing device is in this
case preferably provided between a cleaning nozzle and a second
cleaning element in the form of a polishing means such as a brush.
However, it would also be possible that the rinsing device is
provided in the region of the brush, or even after the latter.
[0020] The present invention also relates to a method for
transforming plastic preforms into plastic containers, wherein the
plastic preforms are expanded inside a cavity through the
application of a medium to form plastic preforms, and wherein this
cavity is formed by at least one inner wall of the blow mould, and
the blow mould can be transferred from an open state to a closed
state. Furthermore, a cleaning mode is provided, in which no
plastic container is accommodated inside the blow mould and at
least one region of the blow mould is cleaned.
[0021] According to the invention, the cleaning takes place at
least partially and preferably entirely in an open state of the
blow mould and a first cleaning element for cleaning the inner wall
of the blow mould is arranged at least at times outside the blow
mould. This element is provided outside the blow mould in
particular in a conventional operating mode, i.e. in a mode other
than the cleaning mode. Preferably, this cleaning element is
provided outside the blow mould in a closed state of the
latter.
[0022] However, such a cleaning element is not provided exclusively
for use in blow moulding machines. Cleaning by means of a CIP
apparatus ("CIP cleaning") is possible in particular in apparatuses
for treating plastic preforms and/or plastic containers. The CIP
cleaning of the preferential heating module via an insertable rod
or an automaton from outside would be conceivable. In this
connection, a preferential heating module is understood to mean a
device suitable for controlling the temperature of at least one
plastic preform in such a way that it has a temperature profile in
one direction of expansion. If, for example, the temperature
profile extends around the circumference, it is possible during a
subsequent expansion of the plastic preform to expand hotter
regions to a greater extent than cooler regions. It is thus
possible in a simple manner to produce for example plastic
containers which have an oval cross section at least in some
parts.
[0023] The cleaning of other treatment units by means of a CIP
apparatus is also possible, such as sterilisation apparatuses for
example. By way of example, the CIP cleaning of an H.sub.2O.sub.2
module (hydrogen peroxide sterilisation module) via an insertable
rod or an automaton from outside is conceivable.
[0024] In one advantageous method, the blow mould is opened and a
liquid cleaning agent is applied to the inner wall in the open
state.
[0025] In a further advantageous method, the inner wall is cleaned
by a mechanical cleaning element in an open state of the blow
mould. This cleaning by the mechanical cleaning element takes place
in particular after the application of the fluid.
[0026] The blow mould is advantageously transported, namely both
during the operating mode and in particular also during the
cleaning mode.
[0027] In a further advantageous method, the cleaning fluid is left
on the inner wall of the blow mould for a predefined period of time
in order to act thereon.
[0028] Advantageously, a rinsing mode is also provided, in which
the inner wall is rinsed. This rinsing mode is advantageously
provided after the application of the cleaning agent and before or
after the polishing or cleaning of the inner wall with the brush or
the cleaning element. In a further preferred method, the brush or
the cleaning element is laterally inserted during this, i.e. in a
direction perpendicular to the longitudinal direction of the blow
mould.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Further advantages and embodiments will emerge from the
appended figures:
[0030] In the figures:
[0031] FIG. 1 shows a perspective view of an apparatus for the
transformation; and
[0032] FIG. 2 shows a schematic view of an installation according
to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] FIG. 1 shows an apparatus for transforming plastic preforms
(not shown) into plastic containers (not shown). This apparatus
comprises a main carrier 11, on which a blow mould 2 is arranged in
a blow mould carrier 3 (in each case shown only partially).
[0034] Formed inside the blow mould 2 is a cavity 4, inside which
the plastic preforms are expanded through the application of
compressed air to form plastic containers. Furthermore, the
apparatus comprises a stretching rod 12, which is movable here in
the longitudinal direction L in order to stretch the plastic
preforms. Reference 22 denotes a first blow mould half and
reference 24 denotes a second blow mould half. In addition, the
blow mould also has a bottom or a bottom part which closes the
cavity 4 in the downward direction during operation. Reference 14
denotes a pressure application device or blowing nozzle which
applies compressed air to the plastic preforms.
[0035] FIG. 2 shows a schematic view to illustrate a cleaning
procedure. This shows in detail a machine in a preferably special
cleaning mode. More specifically, this is an automatic cleaning
process which nevertheless can be incorporated on machines that are
already in development and on mould changing machines that have
already been developed by the applicant. This mould changing device
already has the ability to open the mould carrier automatically and
also to loosen appropriate fixing screws and tighten these again.
This arrangement also already allows an automatic closing of the
mould carrier.
[0036] For use as a cleaning device, in particular the fixing
functions are replaced by the cleaning function. In this case, the
mould is unlocked and opened in a first stage or the region denoted
by reference A. A spray head 16 applies a cleaning agent to the
inner wall of the open blow mould 2. For this purpose, this spray
head 10 may be moved (arrow P1) by means of a transport or
displacement device into the inner region of the blow mould 2,
which is now open, or else can be guided over the inner surface 8
of the blow mould by means of a special device, such as a robotic
arm for example, and can spray said surface.
[0037] It would also be possible that a plurality of such spray
heads are provided. For example, use could be made of spray heads
which are set in rotation by the cleaning medium passing through,
and which thus dispense the cleaning agent in the full
circumferential direction. A plurality of such spray heads could
also be arranged one above the other in the longitudinal direction
L of the blow moulds 2 shown in FIG. 1.
[0038] In the region denoted by reference B, the cleaning agent
acts on the inner surface 8 of the blow mould 2 (cf. FIG. 1). It
would also be possible to close the blow mould again in this
region, but in the embodiment shown in FIG. 2 the blow mould 2
remains open in this state. In the section denoted by reference C,
a second cleaning element 18 is used which mechanically cleans the
sprayed inner surface. This may be for example a rotating polishing
head which cleans the inner surface. At the same time as this
polishing process, the rinsing liquid, such as distilled water for
example, may also be applied to the inner surface. However, this
application of distilled water could also take place at the end of
the region B, or after the polishing process.
[0039] The cleaning element 18 is also moved into the inner region
of the open blow mould 2 for cleaning purposes. However, it would
also be possible that a corresponding cleaning element is moved
into the blow mould from above or from below. Depending on the
geometric dimensions, two polishing elements in the form of two
parallel brushes would also be conceivable, which mechanically
clean the inner wall 8.
[0040] After the region C, the blow mould is closed again.
Reference 15 denotes the rotating carrier (arrow P2) on which the
blow moulds 2 are arranged, and reference 10 denotes the cleaning
device in its entirety. In addition, the apparatus may have cams
(not shown) which bring about the opening and closing of the blow
moulds 2. Cams which move the cleaning elements 16 and 18 into the
open blow mould and out of the latter may additionally also be
provided. However, these movements may also be brought about by
electric motors and in particular by servo motors.
[0041] By virtue of the mould cleaning according to the invention,
there is no need for manual cleaning which is very complicated in
the prior art. For example, the moulds must at present be placed
into a cleaning fluid during storage in a mould changing carriage.
Furthermore, there is the advantage that this automatic mould
cleaning can be carried out even while the blow moulds are still
very hot in parts, which is not possible in the case of manual
cleaning due to the risk of injury to the user. However, these
increased temperatures, particularly of the inner surfaces 8, offer
the advantage of a possible greater efficiency of the cleaning
agent and of the cleaning process per se. Preferably, the apparatus
according to the invention has a special cleaning mode, which may
be provided for example as an interval circuit. Furthermore,
removal or opening of the blow moulds by the user is no longer
necessary, and the safety risk is reduced since the protection
circuit of the machine remains closed even during the cleaning.
[0042] Furthermore, as mentioned above, an increased temperature of
the blow mould can be maintained even during the cleaning, or the
blow mould may also be temperature-controlled or cooled during the
cleaning. This ensures a quicker restart after the cleaning
process.
[0043] It is pointed out that the cleaning arrangement according to
the invention can also be retrofitted on already existing
installations. As shown in FIG. 2, both the cleaning element 16 or
the spray head 16 and the cleaning element 18 are arranged in a
stationary manner relative to the direction of rotation of the
carrier 15. However, it would also be possible to arrange these
elements 16, 18 in a movable manner, for example on the carrier 15.
In a cleaning mode, the individual blow moulds 2 can be moved
(preferably in cycles), so that for example a specific blow mould
remains in a correct position and then the cleaning processes are
carried out.
[0044] All of the features disclosed in the application documents
are claimed as essential to the invention in so far as they are
novel individually or in combination with respect to the prior
art.
LIST OF REFERENCES
[0045] 1 apparatus [0046] 2 blow mould [0047] 3 blow mould carrier
[0048] 4 cavity [0049] 8 inner surface [0050] 10 cleaning device
[0051] 11 main carrier [0052] 12 stretching rod [0053] 14 pressure
application device [0054] 15 carrier [0055] 16 first cleaning
element, spray head [0056] 18 cleaning element [0057] 22 first blow
mould half [0058] 24 second blow mould half [0059] 26 bottom part
[0060] A, B, C region [0061] L longitudinal direction [0062] P1, P2
arrows
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