The invention relates to a metering apparatus for the volumetric metering of pourable filler.
Volumetric metering is commonly undertaken for the metering of dry, pourable filler, such as powder, granulated material or the like, in particular in the area of washing and cleaning detergents, pharmaceutics or food supplements, by means of which volumetric metering a part quantity of the filler is volumetrically delimited and then transferred into a target cavity (container, capsule, et cetera).
In the case of so-called chamber metering, a housing and a metering slide, which is movable relative to the housing, are provided for this purpose, the housing and the metering slide together defining a metering chamber. The filler, in this case, flows into the metering chamber which determines the quantity of powder or granulated material to be dosed as a result of its volume. The metering slide is movable horizontally in the usual configurations of such metering apparatuses. A feed opening present in the housing is closed, in this connection, as a result of the metering slide moving horizontally and at the same time the metering chamber moving away from the feed opening. By way of the same horizontal movement, the metering chamber is moved to coincide with an outflow opening of the surrounding housing, as a result of which the metering chamber is open at the bottom. The filler flows or trickles out of the chamber into the receptacle to be filled.
As a result of the horizontal movement, a lateral offset is necessary between the feed and outflow openings in which the filler is completely delimited and consequently dosed, which entails a considerable amount of space required at the side. In the case of multi-row filling points for the simultaneous filling of target containers that are arranged in several rows, the use of such a doser is consequently limited or even excluded. In addition, it must be mentioned that a small quantity of powder always escapes to the side during the horizontal movement. The quantity accumulates and has to be sucked up manually again and again at certain time intervals, which results in a reduction in production times. Adapting the volume of the metering chambers to the desired target volumes of the powder or of the granulated material when requirements change is costly in time and money. Between the horizontally moved metering slide and the housing are large-area sliding surfaces which rub against one another during the named relative movement. Powder or dust is able to pass between the sliding surfaces, which increases friction and promotes wear. When the filler in the cavity to be filled has additionally to be compacted, this is also difficult in the case of metering with a horizontal closure. In addition, it is not always possible to avoid the filler trickling in an unwanted manner out of the metering chamber.
It is an object of the invention to provide a metering apparatus having a more compact configuration wherein the need for cleaning is reduced.
According to the invention, it is provided that the metering slide is developed as a vertical slide with a stroke axis that is vertical in a usual operating position, that the housing includes a guide surface for the metering slide which extends in the direction of the stroke axis, and that the metering slide includes a boundary surface which corresponds with the guide surface and abuts in a sliding manner against the guide surface. Proceeding from the boundary surface a metering recess is introduced into the metering slide and/or proceeding from the guide surface a metering recess is introduced into the housing, wherein with the metering slide in a stroke position in which the metering recess is covered by the guide surface and/or by the boundary surface, the metering chamber is formed by the metering recess, the guide surface and/or the boundary surface.
In a corresponding operating method according to the invention, the metering slide, which is realized as a vertical slide, is first of all moved into a starting position in which the metering recess is at least in part not covered by the guide surface and/or the boundary surface. With the vertical slide in the starting position, the granulated material or a similar filler trickles out of a storage container into the metering recess. Proceeding from this, the vertical slide is first of all moved into a middle position in which the open side of the metering recess is completely covered by the guide surface and/or by the boundary surface. At the same time, the guide surface abuts in a sealing manner against the boundary surface of the metering or vertical slide above and below the metering recess. In this state, a metering chamber which is precisely defined geometrically with regard to its volume is formed by the metering recess and the inner guide surface which is completely filled with the pourable filler. As a result, a part quantity of the filler is defined, the volume of which corresponds to the volume of the metering chamber.
As a result of a further vertical stroke movement of the metering slide into a third position, the metering recess exits from its cover at least in part such that the measured part quantity of the filler contained in the metering recess is able to trickle out completely and passes as a volumetrically dosed unit quantity into a target cavity located below it. The metering slide is then moved back again into its starting position described above, from which a further metering operation can be carried out with the above-described method steps.
The metering apparatus according to the invention is simple in configuration and can be produced in a cost-efficient manner. As just a vertical stroke movement of the metering slide is necessary, the arrangement with regard to its lateral directions, which are located transversely with respect to the vertical stroke axis, is very compact. As no space is necessary for lateral stroke movements, several combinations of vertical slides and associated guide openings can be arranged closely side by side. Target containers that are located close together are able to be filled at the same time. The aforementioned applies to all lateral directions such that even several rows of target containers that are located close together, for example in a matrix-shaped arrangement, are able to be filled at the same time.
On account of the pure vertical movement of the metering slide, only small-area friction pairings are generated between the inner guide surface of the guide opening realized in the housing and the outer boundary surface of the metering slide. The corresponding surfaces can be matched precisely to one another geometrically at little expense such that the ingress of wear-increasing powder or dust can be suppressed, at least, however, reduced to a minimum. It must also be emphasized that as a result of the configuration according to the invention being closed in the lateral and radial direction, no powder can be lost in the lateral direction as in the prior art. Maintenance and cleaning expenditure are reduced to a minimum. The yield of the prepared filler is maximized.
Less wear is generated overall. Over and above this, the vertical slide is smaller and consequently its mass is smaller compared to horizontal slides according to the prior art such that high cycle rates are able to be run.
In a preferred embodiment, a guide opening, which extends along the named stroke axis, is realized in the housing with an inner guide surface for the metering slide. The metering slide comprises an outer boundary surface which corresponds with the inner guide surface. A metering recess is introduced into the metering slide proceeding from the outer boundary surface. With the metering slide in a stroke position in which the metering recess is completely covered by the inner guide surface, the metering chamber is formed by the metering recess together with the inner guide surface. A compact, coaxial configuration is created where the metering slide can also be used as a compaction element. Where little space is required at the side, a plurality of individual metering apparatuses can be arranged close together in order in this way to fill target cavities which are located close together.
In a further advantageous embodiment, the housing includes a central metering journal, which extends along the stroke axis, with an outer guide surface for the metering slide, wherein the metering slide is realized as a metering sleeve which surrounds the metering journal in the circumferential direction and comprises an inner boundary surface which corresponds with the outer guide surface. Proceeding from the outer guide surface, the metering recess is introduced into the guide journal, wherein with the metering sleeve in a stroke position in which the metering recess is covered by the inner boundary surface, the metering chamber is formed by the metering recess and the inner boundary surface. The metering stroke movement of the outside metering sleeve is separate from a subsequent compaction operation. An optional compaction movement of the central guide journal has no disadvantageous reciprocal effect on the filling and metering operation.
In the case of a further expedient embodiment, realized in the housing is an annular gap, which extends along the stroke axis and is defined on the inside by a central guide journal with an outer guide surface as well as on the outside by a housing outside part with an inner guide surface for the metering slide. The metering slide is realized as a metering sleeve which is guided in a sliding manner in the annular gap and comprises an inner boundary surface which corresponds with the outer guide surface as well as an outer boundary surface which corresponds with the inner guide surface. At least one metering recess is formed by a window which breaks through the metering sleeve, wherein with the metering sleeve in a stroke position in which the at least one metering recess is covered by the inner and the outer guide surface, the metering chamber is formed by the metering recess, the inner guide surface and the outer guide surface. An outflow channel which corresponds with the window is realized in the housing outside part. In this case too, the potentially disadvantageous reciprocal effect between, on the one hand, metering and filling and, on the other hand, compaction is non-existent. In addition, several target cavities can be filled simultaneously and the filling compacted or homogenized using only one metering apparatus.
It can be expedient to produce the metering slide, which is realized as a vertical slide, for example from a flat material with a rectangular cross section. In this connection, the possibility arises of arranging one or several metering recesses on one or two sides which are located opposite with reference to the stroke axis. In a preferred manner, the metering slide is realized as a rotation body with reference to the stroke axis, wherein it extends around the metering recess in a ring-shaped manner and, in this case, divides the boundary surface and/or the guide surface into a bottom surface portion and a top surface portion. Accordingly, the corresponding guide surface or the corresponding boundary surface is developed in a cylindrical manner. As a result of the development as a rotation body, very precise production tolerances can be achieved at little expense. As a result, the desired metering volume is adjustable in a precise manner. Then again, on account of the high level of production accuracy and on account of the lack of corners and edges, precisely defined friction pairings can be produced between the guide surface and the boundary surface and these comprise further reduced wear in operation.
Different, almost arbitrary forms can be considered for the geometric development of the metering recess. In a preferred manner, the metering recess comprises a bottom cover surface and a top cover surface, when viewed in the longitudinal section of the metering apparatus, the bottom cover surface runs out of the metering recess at an angle and/or the top cover surface runs into the metering recess at an angle. In the case of a top cover surface which is angled in such a manner, with the metering slide in the inflow position, the flow of the pourable filler into the metering recess is promoted, whereas with the metering slide in the outflow position, the flow of the filler out of the metering recess is also promoted by the angled bottom cover surface.
In an advantageous further embodiment of the invention, a sealing seat is provided below the guide opening in the housing, wherein a sealing surface, which corresponds to the sealing seat, in a preferred manner is angled and in particular conical, is realized below the metering recess on the metering slide. As once the metering and filling of the target cavity have been carried out, the metering slide is raised again to its starting position, the sealing surface thereof then abuts against the sealing seat. Powder residue trickling out is reliably suppressed such that the metering accuracy is able to be increased even further. Such powder residue is additionally prevented from trickling, for example, onto sealing surfaces of blister packages or the like such that once the metering and filling has been carried out, the target container can be closed in a reliable and sealed manner. In addition, the angled sealing surface and the angled sealing seat are self-cleaning as the corresponding top surfaces are angled in the direction of flow of the filler and the filler consequently automatically follows gravity.
In an advantageous embodiment, the housing and/or the metering slide includes a bottom slide part and a top slide part, wherein a bottom cover surface of the metering recess is realized on the bottom slide part and a top cover surface of the metering recess is realized on the top slide part. The relative positions of the bottom slide part (18) and the top slide part (19) are adjustable with respect to one another measured in the direction of the stroke axis (5). As a result, a volume of the metering recess or of the metering chamber, and consequently of the metering quantity of the filler, is able to be adapted with simple means in dependence on the requirement.
Depending on the requirement, it can be practical for the metering slide to include a compaction punch on its bottom end. As a result of a corresponding vertical stroke of the metering slide, the metering product already filled into the target cavity can be compacted by a desired amount within the same operating cycle.
The invention will now be described with reference to the drawings wherein:
The metering apparatus includes a housing 2 and a metering slide 3 which is movable relative to the housing 2. The housing 2 is positioned in a stationary manner. The initially empty target cavity 23 is prepared below the housing 2 for the metering and filling operation and once filling has been effected, is replaced for another empty target cavity 23. The arrangement shown, made up of the metering apparatus and the target cavity 23, is shown in its usual operating position. A vertical stroke axis 5 is located almost approximately in the direction of the working load or parallel thereto. The metering slide 3 is realized as a vertical slide, extends along the vertical stroke axis 5 and is displaceable up and down relative to the housing 2 in the direction of the vertical stroke axis 5.
A guide opening 6, which extends along the stroke axis 5 and comprises a constant cross section with a closed circumferential inner guide surface 7 along the stroke axis 5, is realized in the housing 2. The cross section of the guide opening 6 can be, for example, rectangular or polygonal and in the shown preferred embodiment is circular. A cylindrical development of the guide opening 6 follows from the circular cross section in conjunction with the constant cross section along the vertical stroke axis 5.
The metering slide 3 includes an outer boundary surface 8 which corresponds geometrically with the inner guide surface 7 and is surrounded by the inner guide surface 7 completely in the circumferential direction and in part in the direction of the stroke axis 5. In the region of the uninterrupted boundary surface 8, the cross section of the metering slide 3 is therefore identical to the cross section of the guide opening 6, in this case therefore circular. In the case of a vertical stroke movement of the metering slide 3, the outer boundary surface 8 slides in an at least approximately gap-free and play-free manner along the inner guide surface 7 realized in the housing 2.
Proceeding from the outer boundary surface 8, a metering recess 9 is introduced into the metering slide 3. The metering recess 9 can be shaped one side relative to the stroke axis 5. However, several metering recesses 9 can also be provided in the direction of the stroke axis 5 one above another and/or on different sides relative to the stroke axis 5. In the embodiment shown, the metering slide 3 is realized as a rotation body with reference to the stroke axis 5. The metering recess 9 extends around the stroke axis 5 in a ring-shaped manner and at the same time divides the boundary surface 8 into a bottom surface portion 10 and a top surface portion 11. Consequently, the metering recess 9 is defined with reference to the stroke axis 5 at the bottom by a bottom cover surface 12 which proceeds from the bottom surface portion 10, at the top by a top cover surface 13 which proceeds from the top surface portion 11 and radially inward by an inside surface 22. The bottom cover surface 12, the top cover surface 13 and the inside surface 22 extend around the stroke axis 5. Proceeding from the bottom surface portion 10 of the boundary surface 8, the bottom cover surface 12 extends radially inward in the longitudinal section shown and at the same time at an upward angle to the inside surface 22. Consequently, the bottom cover surface 12 runs out of the metering recess 9 at an angle for the subsequent emptying operation for the filler described further below. Proceeding from the top surface portion 11, the top cover surface 13 extends radially inward and at a downward angle to the inside surface 22. Consequently, the top cover surface 13 runs into the metering recess 9 at an angle for the initial filling operation for the filler described further below. It can be practical for only one of the two cover surfaces (12, 13) or none of them to comprise the angled progression. As a result of the angled progression shown, the metering recess 9 is tapered toward the stroke axis 5 proceeding from the outer boundary surface 8 along the stroke axis 5 in the longitudinal section shown.
Along with further structural details, another metering and filling method according to the invention for the granulated material 2 is described below. In a first method step, the metering slide 3 is raised into a top starting position, as is shown in
In addition, the storage chamber 14 includes a bottom 15 which runs radially from out to in and additionally also at a downward angle toward the guide opening 6. This also facilitates the inflow of filler into the metering recess 9 especially in conjunction with the angled top cover surface 13. The angles of inclination of the two cover surfaces (12, 13) and of the bottom 15 relative to the stroke axis 5 are approximately 45° in the embodiment shown and in a preferred manner in each case can be within a range of between 30° and 60°. However, other angles of inclination can also be practical.
Proceeding from the starting position according to
It can be practical as an option for the metering slide 3 to include on its bottom end 20 a compaction punch 21 which is provided in this case with a flat pressing surface located perpendicularly or transversely with respect to the stroke axis 5.
Proceeding from the position according to
It can be also seen with renewed reference to
In its top region, the metering sleeve 28 surrounds the mid region of metering journal 27 at a radial spacing, inside which the storage chamber 14 for the granulated material 1, not shown in any detail, is formed. Here too, the storage chamber 14 includes a ring-shaped circumferential bottom 15 which is realized on the metering sleeve 28 and runs down to the metering recess 9′ at an angle.
Comparable to the embodiment according to
When comparing the embodiment according to
The metering journal 27, which extends centrally along the stroke axis 5, includes an outer guide surface 7′, while the metering sleeve 28, which surrounds the metering journal 27 in the circumferential direction, includes an inner boundary surface 8′ which corresponds with the outer guide surface 7′. Accordingly, proceeding from the outer guide surface 7′, the metering recess 9′ is introduced into the metering journal 27. The metering slide 3, which is realized as the metering sleeve 28, and also the metering journal 27 as part of the housing 2 are realized in each case with reference to the stroke axis 5 as rotation bodies, the metering recess 9′ extending around the metering journal 27 in a ring-shaped manner. Because of the ring-shaped development of the metering recess 9′, the outer guide surface 7′ is divided into a bottom surface portion 37 and a top surface portion 38, while the corresponding inner boundary surface 8′ is developed continuously in a cylindrical manner overall.
In a first method step and in the starting position according to
In the next method step, proceeding from the representation according to
In an analogous manner to the embodiment according to
However, in the embodiment shown no use is made of the aforementioned option. Rather, the metering apparatus includes on its bottom surface a bridging sleeve 35 which, proceeding from the metering sleeve 28, extends downward and reaches up to the edge of the target cavity located below it. The cross sectional format of the metering apparatus does not consequently have to be in accordance with the outline format of the target cavity 23 such that different target cavities 23 with different forms are able to be filled using the same metering apparatus. In each case, the bridging sleeve 35 ensures that the measured granulated material 1 passes completely into the target cavity 23 irrespective of its format. The compaction of the granulated material 1 inside the target cavity 23 is effected then in a separate method step at a subsequent processing station not shown here.
In contrast to the aforementioned embodiments, realized in the housing 2 is an annular gap 29, which extends along the stroke axis 5 and is defined on the inside by a central guide journal 36, which is also associated with the housing 2, with an outer guide surface 7′ as well as on the outside by a housing outside part 30 with an inner guide surface 7. The guide surfaces (7, 7′) are developed as coaxial cylinders. The metering slide 3 is realized as a metering sleeve 28 which is guided in a sliding manner in the named annular gap 29 and comprises an inner boundary surface 8′ which corresponds with the outer guide surface 7′ as well as an outer boundary surface 8 which corresponds with the inner guide surface 7.
At least one metering recess 9, which is developed here as a window 31 which breaks through the metering sleeve 28, is formed in the metering sleeve 28. With the metering sleeve 28 in a middle stroke position shown in
In an analogous manner to the embodiments looked at beforehand, a storage chamber 14 for the filler is realized above the metering chamber 4 in the housing 2, a bottom 15 of the storage chamber 14 running down at an angle to the metering recesses 9. With consideration to the number of the several metering recesses 9, the angled bottom 15 is developed in a conical manner in the embodiment shown, but can also be developed in the manner of a pyramid or analogously with individual angled surfaces.
Continuing the analogy with the remaining embodiments, the metering slide 3 or the metering sleeve 28 includes a bottom slide part 18 as well as a top slide part 19 with associated top and bottom cover surfaces (12, 13), the relative position of the bottom slide part 18 and the top slide part 19 with reference to one another measured in the direction of the stroke axis 5 being adjustable, and as a result of which the volume of the metering chamber 4 is adjustable in the manner described previously.
In the next method step according to
In the subsequent method step, the metering sleeve 28 is lowered further according to the arrow 34, as is shown in
In an optional, subordinate method step according to
Unless expressly mentioned otherwise, the remaining features, references, method steps and application options of the embodiments shown here are consistent with one another.
It is understood that the foregoing description is that of the preferred embodiments of the invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
20 2013 008 523.1 | Sep 2013 | DE | national |
This application is a continuation application of international patent application PCT/EP2014/002603, filed Sep. 25, 2014, designating the United States and claiming priority from German application 20 2013 008 523.1, filed Sep. 25, 2013, and the entire content of both applications is incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
Parent | PCT/EP2014/002603 | Sep 2014 | US |
Child | 15081725 | US |