The invention relates to a filling element according to the preamble of claim 1, to an insert for use with filling elements according to the preamble of claim 8 and to a filling machine according to the preamble of claim 10. Filling elements for the filling of bottles or similar containers are known in a variety of embodiments, in particular in an embodiment having the features of the preamble of claim 1, i.e. having an insert that acts as a gas barrier and/or swirl body for the filling material and that is located in the liquid channel in the direction of flow of the filling material upstream of the valve seat of the liquid valve to improve the filling material flow when the liquid valve is open or during the filling phase (EP 1 593 648 B1, EP 0 546 346 A1, DE 41 40 524 A1). What this prior art has in common is that the respective insert moves with the liquid valve when the latter opens and closes, this having among other things the disadvantage that when the liquid valve closes, a motion component or acceleration in the direction of the discharge opening, and additionally amplified by the insert, is imparted to the volume of the liquid filling material that is present at this time between the discharge opening and the valve body or insert. This then means an increased residual volume that is additionally introduced into the respective already filled container with increased motion energy and which in the case of a carbonated filling material in particular leads to an agitation of the filling material in the container with a consequential release of CO2 gas and an additional frothing.
The object of the invention is to disclose a filling element which avoids the disadvantages of known filling elements while retaining the fundamental advantages of an insert embodied as and/or acting as a gas barrier and/or swirl body.
A filling element according to patent claim 1 is configured to resolve this object. An insert for use with filling elements is the subject-matter of claim 8. A filling machine for filling bottles or similar containers is the subject-matter of claim 10.
Surprisingly it has been found that the inventive embodiment can significantly enhance the properties of a filling element, in particular also as regards reducing the size and velocity or acceleration of the residual or overrun volume that is still being introduced into the respective container during the closing of the liquid valve.
Further embodiments, advantages and possible applications of the invention arise out of the following description of embodiments and out of the figures. All of the described and/or pictorially represented attributes whether alone or in any desired combination are fundamentally the subject matter of the invention independently of their synopsis in the claims or a retroactive application thereof. The content of the claims is also made an integral part of the description.
The invention is explained in detail below through the use of an embodiment example with reference to the figures.
The filling valve shown in
During filling, in particular pressure filling, the respective container is in sealed position against filling element 1, i.e. it lies with its mouth edge or mouth bead, which surrounds the container mouth, against a seal 6 provided at the base of the filling element housing and which annularly encircles discharge opening 5 and which in the depicted embodiment forms part of a centering tulip 7 for centering the respective container relative to filling element 1.
On the same axis as filling element axis FA is provided a valve tube or gas tube 8 which projects downwards by its lower open gas tube end 8.1 beyond discharge opening 5 and ring seal 6, extends over part of its length through liquid channel 3 and which at the top of liquid channel 8 [sic] is guided out of liquid channel 3 sealed by means of a seal 9 configured for example as a membrane.
On the same axis as filling element axis FA is further provided a rod-like probe 10 which determines the fill level during filling of the respective container, which extends through gas tube 8 and whose lower probe end projects out of the lower open gas tube end 8.1 forming an annular gas channel 11 (return gas channel) encircling probe 10 inside gas tube 8. This gas channel 11 is open at lower gas tube end 8.1 and at the upper end of gas tube 8 opens out into a chamber 12 which like gas channel 11 is part of the gas paths of filling element 1 which control the respective filling process in the manner also known to the skilled person.
In liquid channel 3 there is provided a liquid valve 13 which is opened and closed for the controlled dispensing of the liquid filling material as a function among other things of the signal of probe 10. For liquid valve 13, gas tube 8 is configured, over a lower partial length which is relatively short and accommodated in liquid channel 3, as valve body 14 which engages with a valve seat 15 which is formed on the conical interior surface 16 of the tapering lower section of recess 3.1. For the opening and closing of liquid valve 13, gas tube 8 can be moved up and down in a controlled fashion in the manner of a valve stem in the direction of axis FA by a for example pneumatic actuating device 17 (double arrow A). Valve body 14 is executed with a section having a circular-cylindrical peripheral surface which concentrically encloses filling element axis FA.
The filling of the respective container with filling element 1 is effected with a filling method known to the skilled person, for example with a pressure or counter-pressure filling method in which the container present in sealed position against the filling element—for example after a pre-evacuating and/or purging with inert gas (CO2 gas)—is pre-stressed, pressure-filled and at the end of the filling process at least partially let down to ambient pressure by gas channel 11.
A particular feature of filling element 1 is in the insert generally indicated by 18 in the figures and shown in detail in
As depicted in particular in
Insert 18 is moreover shaped so that ring section 19 is proud by a part-region 19.1 of the top of bladed structure 21 which on the underside of insert 18 forms a conical outer contour following the line of tapered surface 16 and on the periphery of insert 18 forms a circular-cylindrical outer contour concentrically encircling axis EA and following the circular-cylindrical cross-section of recess 3.1. Like wall sections 20, bladed structure 21 is also proud of the underside of ring section 19. In between interspaced wall sections 20, bladed structure 21 forms a plurality of flow channels which are open on the periphery and on the underside of annular insert 18 as well as on the top and inside of annular insert 18 (outside ring section 19).
In detail, insert 18 is inserted in recess 3.1 forming liquid channel 3 in such a way that bladed structure 21 lies with its conical underside against surface 16 and with its periphery against the interior surface of recess 3.1 in front of the conically narrowing section of this recess, as shown in
Surprisingly it has also been found that the residual volume of filling material which is accelerated by valve body 14 which moves as liquid valve 13 closes is significantly reduced through the use of insert 18 and especially through its non-moving arrangement. This is due among other things to the fact that when liquid valve 13 is open, the liquid filling material leaving the flow channels of bladed structure 21 flows from the side into the part of liquid channel 3 which is located beneath opened valve body 14 and which opens into discharge opening 5, and that the filling material stream leaving the flow channels of bladed structure 21 is therefore interrupted by valve body 14 moving square to the direction of flow as liquid valve 13 closes.
The beneficial effects which are achieved with fixed insert 18 are particularly marked when wall sections 20 which form bladed structure 21 are as closely adjacent to one another as possible with their edges or narrow sides of a circular-cylindrical plane of motion lying on the inside relative to axis EA and preferably oriented parallel to that axis, in which (plane) that section of valve body 14 which has the circular-cylindrical peripheral surface moves, so that at least when liquid valve 13 is open the entire flow cross-section of the flow channels formed between wall sections 20 of insert 18 is essentially greater than the flow cross-section of a gap which may exist between the peripheral surface of valve body 14 and the interior surface of insert 18. The distance of the inside edges or narrow sides of wall sections 20 from this plane of motion is preferably no more than 0.5 mm. During the closing of liquid valve 13 therefore the radially inside discharge openings of the flow channels formed between wall sections 20 are occluded increasingly and tightly, or at least to the greatest possible extent tightly, by valve body 14. Moreover the inside edges or narrow sides of wall sections 20 are arranged for example on a common notional circular-cylindrical surface which is then preferably also the circular-cylindrical surface of the inside of ring section 19.
The invention has been described hereinbefore by reference to one embodiment. It goes without saying that numerous variations as well as modifications are possible without departing from the inventive concept underlying the invention.
It is for example of particular benefit if a gas barrier is used in conjunction with a restricting of the return gas flow. Surprisingly a considerable improvement in the fill level accuracy of the filled containers comes about when such a method is applied. There is in particular a significant reduction in the standard deviation of the measured actual fill levels.
According to the current level of knowledge, restricting the return gas makes for a more even inflow of the filling material into the container, or a more even, i.e. more turbulence-free, flowing of the filling material through the gas barrier. As a result of these improved flow conditions, the (after-flowing) filling material is arrested almost immediately and almost completely by the gas barrier at the instant when the desired fill level is reached. The quantity of filling material still flowing after the desired fill level is reached is at any rate significantly reduced.
Number | Date | Country | Kind |
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10 2010 022 875.3 | Jun 2010 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP11/02231 | 5/5/2011 | WO | 00 | 12/5/2012 |