Note: Descriptions are shown in the official language in which they were submitted.
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A Process and a Device for the Filling
of Vessels
Specification
The invention relates to a process for the filling of a
vessel, which has the fe,atures of the preamble o~ claim
1 and a device ~or carrying out the process, which has
the features of the preamble of claim 7.
Such a process and such a device are known from DE-OS
32 ~5 731. Liquid is filled there into a vessel under
counter-pressure. In order to avoid that the liquids
get into the return gas section, probes are disposed
below the return gas line/ which stop the supply o~
uid via a valve. Thus, the filling process is
stopped shortly before the reaching of the opening of
the return gas line. If the liquid or the foam produced
by the filling reaches the first probe, the supply of
liquid is reduced by means of a throttling means so
that the filling process is continued at reduced speed.
If the liquid or the foam reaches the upper probe, the
valve is closed and the supply of liguid is s~opped.
The process forming the genus and a device for carrying
out this pxocess are also known from US-PS 3 918 475.
The device has a long filling ~ube with two valves ~or
a rapid and a slow supply o~ liquid. The filling tube
is provided with two probes. ~or terminating the
~illing pro~ess taking place at atmospheric pressure
the valve controlling the rapid ~low is closed via a
first prob~ when the liquid or the foam reaches a ~irst
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filling level and then, the valve controlling the slow
flow i~ closed upon the reaching of the second probe.
The known processes and devices are not suited for
filling open vessels with liquids tending to form foam,
in particular not in the case of the use of short
filling tubes, since the desixed final filling level of
the liquid can only he precletermilled inaccurately upon
the ~topping of the fillin~ process. I~ liquids such a~,
water are fi:LlPd, ambient air gets in~.o the vessel at
the same time with the liquid. Due to this a foam and
bubble formakion occurs du.ring the filling process to
which the probes respond although th~ liquid level has
not reached the final filling level a~ yet. The extenk
of the error depends on the size of tha foam and bubble
formation, which is of differing siza for dif~erent
liquids. This error makes itself felt quite clearly in
the case of specific water~. A similar effect can al80
occur during filling under counter-pressure.
In view of this prior art, the invention is based on
the object of creating a process for the f;lling o~ a
vessel and a device for carrying out this process, with
which the accuracy of the final filling level is
improved in simple fashion.
~his object is attained according to the invention by a
process with the features of claim 1 and a device with
the features of claim 7.
Due to tha waiting time after the stopping of the first
supply o~ liquid it is achieved that the foam which was
formed on the surface of the liquid during the supply
of the liquid is decomposed again. Due to this, a
smooth surface of the liquid is formed which i5 located
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below the first probe. Since, after this waiting time,
liquid is supplied again, until one of the probes
responds again and the supply o~ liquid is then
stopped, the vessel can be filled to the desired ~inal
filling level with greal acuracy. Since the second
.filling process is only very short, no new ~oam is
formed on the sur~ace of the liquid so that the final
filling level is achieved by the ~act that the liquid
itself and not the foam causes the second responds of
one of the probes. Thus, the desired final ~illinq
level is precisely reachecl.
According to an advantageous further development oP the
invention, the supply of liquid is immediately inter-
rupted upon the first response of the probe. This
simplifies thè control of the device, since a reduction
of the flow of liquid and the device necessary ~or
this, are then not required.
A further simplification of the device can be ~chieved
by the fact that only one probe is used for measuring
the filling level. The supply of liquid is then stopped
for the first time upon the response of the probe due
to the foam on the surface of the liquid. The same
probe responds the second time, if, after the waiting
time, during which the Poam is decomposed, liquid is
again supplied and the surface of the liquid which is
now ~ree from foam reaches the pro~e again.
It may also be advantageous if two probes are provided,
the second probe being disposed above the first probe.
The distance of the two probes can be adapted to the
filling conditions here. This is in particular oP
advantage in the case o~ a rapid supply of liquid or
not too great a foam formation of the liquid.
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It is furthermore advantageous i~ the probes are
disposed on the outer side of the filling tube. The
height of the probes can then be controlled in an
especially simple fashion b~ the immersion depth o~ the
filling tube into the vessel. Moreover, the probes are
easily accessible for control and repair. It is also
advantageous if t}le probes have a metal core connected
to a voltage source, whlich is insulated from the
filli.ng tube by an insulat,ing casing~ These probes can
be di.sposed in simple fashion on the filling tube, have
a high measuriny accuracy and a rapid response time.
It is also advantacJeous if the probes are surrounded by
a protectiny tube, which only spares the lower ends of
the probes. Since then the probes are prokected against
detrimental influences of the ~nvironment, e.g,
scratching by being pushed ag~inst somethinq or soiling
due to liquids or air. The free ends define the
response points which react to the rising liquid or the
foam formed thereon. ThP casing surface o~ the ~illing
tube may advantageously ha~e recesses into which the
probes are inserted in such fashion that the outer
surface o~ the probes is substantially in alignment
with the casing surface of the ~illing tube. It is
achieved due to this that the probes do not project
beyond the casing surface of the ~illing tube, and
damage to the probes is thus avoided.
It is furthermore advantageous if the valve is disposed
in the filling tube. Thus the amount of liquid still
located in the filling tube upon the closing of the
valve can be kept small. It is also of advantage if the
filling tube has a reduced inner diameter below tha
opening of the liquid feed line, the transition area to
the reduced inner diameter forming an edg~less valve
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seat on which the valve rests sealingly in closed
condition. Due to the continuous transition it i6 made
possible in simple fashion that the valve can adopt
various open positions, in which a differenk thxough-
flow of liquid can be controlled by the differing
distance of the valve fro~ the filling tube wall.
~ccording to an advantageous further development o~ the
invention, a pneumatic actuator connected to the
control means i5 provided for the opening and closing
of the valve. A pneumatic cylinder is customarily used.
Thus, a simple, reliably controllable opening and
closing of the valve is made po~sible. The pneumatic
actuator is advantageously designed as a multi-posikion
cylinder. Due to dif~erent positions of the multi-
position cylinder different Plows of liquid can then be
achiev~d. A smaller flow o~ liquid can then in parti-
cular be selected in the second supply of liquid so
that a still more precise stopping at the desired final
filling level can take place.
According to an advantagaou~ urther development of the
invention, a protective gas line is provided which
leads into a protective gas sleeve surrounding the
~illing tube above the vessel to be filled. This is of
special advantage i~ the filling tube is introduced
into the vessel without contact and sealing in order to
avoid a contamination of the opening of the vessel. A
protective gas can be supplied to the vessel in the
area of its opening during the filling process so that
the vessel is protected against the penetration of
ambient air into its opening during the entire filling
process. Moreover, protective ~as line and protective
gas sleeve can be used for cleaning the filling tube
from the outside and to sterilize it, e.g. by the
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introduction of water, hot water, vapour, etc., during
the time during which no vessel is filled.
The invenkion is explained in qreater detail by means
of the drawings in the following.
Fig. 1 shows a cross-section through a first example of
embodiment of the device according to the invention and
Fiy. 2 shows a cross-section through a second example
of embodiment of the device according to the invention.
Fig. 1 shows an example of embodiment of a filling
device 1 in cross-section, below whi~h a vessel 2 is
disposed in the form o~ a bottle to be filled with a
liquid, e.g. mineral water. The filling device
comprises a filling tube 3 whose lower end project.s
into the openiny 4 of the vessel 20 A liquid feed line
5 opens into the filling tube 3. The ~illing tube 3 has
a reduced inner diameter below the opening of the
liquid feed line. The transition area in the filling
tube to the end with the reduced inner diameter forms
an edgeless valve seat 6, on which a valve 7 rests
sealingly in closed condition so that th~ flow of
liquid through the filling tube 3 is interrupted. A
pneumatic cylin~er 8 is disposed for controlling the
valve 7, which opens and closes ~he valve 7 via the
pressure line 90 The pneumatic cylinder 8 can be
designed as a multi~position cylinder so that different
opening positions o the valve 7 are possible, in which
dif~erently large ~lows of liquid can be flow into the
vessel 2 through the filling tube 3.
At the low~r end of the filling tube 3 which projects
into the vessel 2; a recess 10 is formed in the casing
r~ 3
surface of the ~illing tube 3 into which a probe 11 is
inserted. The probe 11 comprises a metal core 12 and an
insulating casing 13 connected to a control means 17 by
means of a line 23 and is disposed in such ~ashi~n in
the recess 10 that its surface is substantially in
alignment with the casing surface o~ the filling tube
3. For the further protection of the probe 11 it is
surrounded by a protecting tube 14 which only leaves
the lower end 15 o~ the probe ll uncovered. Due to
this, the prohe 11 is completely protected against
soiling and the response point of the probe 11 is
exactly defined. :
In the following the process :is described by means o~
the operation of the device according to Fig. 1. The
vessel 2 is filled with l~iquid through the filling tube
3, until the foam formed during filling reaches the
lower end 15 of the probe 11. A signal is supplied to
the control means 17 via the probe 11, due to which th~
pneumatic cyllnder i~ ~ctuated vla the pre~sure lin~ g
so that the filling proaes~ i~ terminated b~ alo5ing
the valve 7.
Due to this, the sur~ace o~ the liquid i~ located below
the lower end 15 of the probe 11. After a predetermined
waiting time of e.~. one second, within which the ~oam
is decomposed, the filling process is started ayain by
opening the valve. This second filling process is then
stopped again, when the liquid reaches the lower snd 15
of the probe 11 for the second time. The signal is
transmitted to the control means 17 via the probe 11,
which actuates the pneumatic cylinder 8 and thus closes
the valve 7. Since, due to the short duration, ~o ~oam
is formed during the second filling proces~, the level
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of tha surface o~ the liquid now corresponds to the
height of th~ response point 15 of the probe 11.
Fig. 2 shows a second example o~ embodiment of the
device according to the invention. The parts of the
device designated with the same reference numerals
correspond to those o~ ~ig. 1 and comply with the
functioning described in this connection inasmuch as
nothing else is explained in the ~ollowing.
Thus, only the differences with respect to the first
example of embodiment are described in the following.
In addition to the recess lO in the casi.ng sur~ace o~
the lower end oP the filling tube 3 into which the
probe is inserted, a recess 10' is pro~ided in the
casing surface, into which the second probe 11' is
inserted. The probe 11' comprises a m~tal core 12'
conn~cted to the control means 17, which is insulated
from the ~illing tube 3 by an insulating casing 13'.
The surface of the probe 11' is furthermore substan-
tially in alignment with the casing surface of the
filling tube 3~ The probe 11' is surrounded by the
protecting tube 14 as is the probe 11. The protecting
tube 14 has a second interruption which leaves the
lower end l9 of the probe 11' ~ree and thus defines the
second response point.
During the filling process, the lower end 15 o~ the
probe 11 responds to the rising surface of the li~uid
or its foam, whereby the valve 7 is closed via tha
control means 17, the pressure line 9 and the pneumatic
cylinder 8. During a predetermined waiting time, tha
~oam settles on the sur~ace of the liquid so that it is
below the lower end 15 of the probe 11. After the
predetarmined waiting time during which the foam has
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settled the filling process begins again as it was
already described in connection with Fig. '. As opposed
to the example of embodiment of Fig. 1, the f illing
process, however, i5 only stopped when the surface of
the liquid which increases again has reached the lower
end 19 of the second probe 11'. A signal is tran~mitted
to the control means 17 via the probe 11', which then
closes the valve 7 via the pneumatic cylinder 8 and the
pressure line 9. Since during the second, only very
short ~illing process no further bubbles or foam are
formed, the level o~ the surface of the liquid
corresponds exactly to the height of the lower end lg
of the probe 11', by means of which the predetermined
filling level is defined.
The device 1 is furthermore mounted on a supporting
plate 20 in this example o~ embodiment. The supporting
plat~ 20 can be designed as a rotating plate and
receive several ~illing devices so that sPveral vessels
2 can be filled at the same time. For this, the support
of the vessel 2 is vertically movable so that the
filling tube 3 can be guided out of the v~ssel 2 and
positioned again in the next vessel 2 at the desixed
height.
The filling deYice 1 comprises furthermore a protectiY~.
gas feed line 21, which opens into a protective gas
sleeve 33 surrounding the ~illing tube 3 above the
vessel 2 to be filled. The opening 4 of the vessel 2
can be prote~ted against contamination during the
~illing process by the supply o~ protective gas via ~he
protective gas line 21 and the protective gas sleeve
22. Moreover, the filling tube can be cleaned at the
out~ide via the protective gas line 21 and the pro-
tective g,as sleeve 22 by means of the introduction of
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water, hot water, vapour, etc., if no ~essels 2 are
filled.
The process according to the invention is described by
means of Fig. 2 in the following. A vessel 2 is fed to
the ~illing device 1 disposed on the supporting plate
20 and positioned at a predetermined suited height with
respect to the filling tllbe 3. This height is selected
in such fashion that the lower end 19 of the second
probe 11' comes to rest in such fashion with respect to
the vessel 2 that the desir~d final height is to be
present there. The valve 7 is opened via the cont,rol
means 17, the pressure line 9 and the pneumatic cylin~
ner 8 so that the liquid to be filled, e.g. water, gets
into the lower end o~ the filling tube 3 and thus into
the vessel 2 via the liquid ~eed line 5 through the gap
formed between the valve 7 and thQ valve seat 6. The
liquid rises in the vessel 2 until the liquid or the
foam on the surface of the liquid reaches the lower end
15 of the probe 11 . The probe 11 which responds to the
liquid or the foam on the surface of the liquid trans-
mits a signal to the control mean~ 17 which closes the
valve 7 via the pressure line 9 and the pneumatic
cylinder 8. The supply of liquid from the liquid feed
line 5 into the vessel 2 is thus interrupted. Due to
the ~illing process via the short filling tube 3 into
the open opening 4 of the ves~el 2 that much air ha~
gotten into the vessel 2 with the liquid or the water
that the surface o~ the liquid consists of foam and
bubbles. During a waiting time aftar the stopping of
the filling process, foam and bubbles are decomposed on
th surfac~ of the liquid so that the surface o~ the
liquid is below the lower end 15 of the probe 11. After
the waiting time which is sufficient for the decomposi-
tion of the foam on the surface of th~ liquid, the
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11
valve 7 is opened automatically again by the control
means 17 via khe pressur,e line 9 and the pneumatic
cylinder 8. The opening of the valve 7 is either
effected in the original position duriny the preceding
filling process or in an intermediate position, in
which the passage between the valve 7 and the valve
seat 6 is smaller than during the first filling pro-
cess. The refilling process is stoppecl when the lower
end 19 o~ the second probe 11' re~ponds to the surface
of the li~uid which rises again. Then the valve 7 i5
clo~ed again by the control means 17 via the pressure
line 9 and the pneumatic cyl.inder 8. Si.nce the refill~
ing process is only very short, thers is no renewed
foam and bubble formation on the surface of the liquid
so that the level of the surface of the liquid corres-
ponds exactly to the predetPrmined filling level which
is determined by the lower end 19 of the probe 11l. ThP
filling tub 3 is removed ~rom the opening 4 of the
vessel 2 by a lowering of the vessel 2 or a lifting of
the filling device 1. Then the vessel 2 is guided ~o
the closing station, and a further vessel 2 is brought
into the filling position so that the filling proces~
described above can hegin anew.
