EP2746172A1 - Method and device for weighing containers on a transport device - Google Patents

Abstract

The method involves starting a weighing station with a container (20) to-be weighed by using a transport device. A weighing surface located at a load cell is positioned at the container located on transport device. Loads of the container is superimposed on the weighing surface. The container is weighed by using the load cell. The vertical loads of the container on the weighing surface is performed either by lifting of the container on transport device or by raising the weighing surface, so that the weight of container rests entirely on the weighing surface. An independent claim is included for a device for weighing containers located on transport device.

Description

I. Field of application

The invention relates to a method and a device for weighing containers, which are located on a transport device.

II. Technical background

Containers such as bottles or tubes, which are transported by means of a transport device and for example are to be filled, closed, printed, packaged or otherwise processed, often also have to be weighed, for example in order to check whether the filled container fulfills the specified conditions. Has reached weight, or for other reasons.

As transport devices are quite different solutions known, for example, a conventional conveyor belt or other known transport device.

In order to weigh the weight of a container located on the transport device, it has hitherto been known to lift the container from the transport device and place it on a weighing cell located laterally next to the transport device, for example, and then to return it to the transport device.

This two-time implementation requires on the one hand a considerable amount of time, and entails follow-up problems, for example, after resetting to the transport device, the correct positioning on the transport device, or when placing on the load cell, the necessary waiting time until the resulting from the settling movement bearing force on the load cell has subsided.

If then at the load cell, the container is not immediately closed - which is usually not due to cycle time reasons - the filled, but open container must be converted back to the transport device, which entails further difficulties and especially the risk of spillage of filling from the open container in itself.

Furthermore, the container should often be filled during weighing in order to achieve an exact filling quantity in the container. Therefore, the still empty container is first weighed by the load cell and thereby determines the tare weight of the container, and then filled the container while it is on the load cell, while continuously weighed so that one with the load cell and with the filling Device-related control ends the filling process as soon as the measured total weight minus the initially measured tare weight, ie the filling weight, has reached the predetermined desired value.

This procedure makes it possible to introduce an exact filling quantity into the container, in contrast to the procedure of starting from an always equal tare weight and only measuring the achievement of a specific total weight by weighing. Because then the variations in the weight of the empty container as well as other weight influences such as other weighed other parts in the weighted total weight and prevent adherence to an exact filling weight.

III. Presentation of the invention a) Technical task

It is therefore the object of the invention to provide a method and an apparatus for weighing of packages available, which despite a simple and flexible construction, a gripping the container and moving from the transport device on a weighing surface and back avoids.

b) Solution of the task

This object is solved by the features of claims 1 and 8 . Advantageous embodiments will be apparent from the dependent claims.

The solution consists in a procedure in which the container to be weighed is weighed on the transport device on a weighing platform by means of a load cell, which is usually located next to the transport device, or viewed in the supervision in the area of the transport device.

By starting the weighing cell on the transport device, where the load cell or several load cells are located, the container to be weighed is positioned by means of the transport device on the weighing surface of a load cell, and of course also stopped the transport device.

For weighing, the weighing surface must now be brought into contact with the container in such a way that the container is supported exclusively on the weighing surface, that is to say it is overloaded.

One possibility is to raise the weighing surface until it reaches the container and further raise it until the container except Engaged with the transport device and the weight of the container rests exclusively on the weighing surface.

Of course, the same effect can be achieved by instead the transport device is lowered with the container until the container lifts from the descending transport device and weighs only with its weight on the weighing surface.

In this case, the position of the container is maintained in the horizontal direction.

The container therefore does not have to be additionally moved in the horizontal direction, and above all not be transferred from the transport device to the side on a load cell located there.

The only vertical movement of weighing surface and / or container of the time required for the implementation of the container is saved and by such a horizontal movement additionally arising problems such as spillage of filling, etc., avoided.

As a rule, container receptacles designed to match the container to be handled are present on the neutrally designed transport device, on or in which the containers fit snugly. Then, in addition to the container and the container receptacle in which it sits, be wholly or partially raised with, and thus be weighed with.

The container receptacle is in each case designed so that it acts self-centering with respect to the male container and / or to the transport device, so that after lifting for the purpose of weighing and subsequent lowering of container and / or container receptacle, the container relative to the transport device back to the exactly the same position as before lifting.

• Entweder soll das momentane Gewicht des Gebindes ermittelt werden: Dann muss bei einem gemeinsamen Verwiegen von Gebinde und Gebinde-Aufnahme das in der Regel bekannte Gewicht der GebindeAufnahme rechnerisch abgezogen werden, was in der Regel eine angeschlossene Steuerung erledigt.
• Oder - was der häufigere Fall ist - es wird ein leeres Gebinde an die Wiegestelle gebracht, dort zunächst das leere Gebinde gewogen, um ein Tara-Gewicht zu erhalten, und anschließend im Wiege-Zustand, also bei fortlaufender weiterer Wiegung, an der Wiegestelle das Gebinde gefüllt. Da die Steuerung mit der Wiegezelle verbunden ist, und gleichzeitig mit der Befüllvorrichtung, beendet die Steuerung den BefüllVorgang, sobald das Soll-Füllgewicht erreicht ist, welches ständig aus der Differenz des aktuellen Wiege-Ergebnisses abzüglich des bekannten Tara-Gewichts ermittelt wird.

Depending on the task, the weighing result is evaluated differently:

• Either the instantaneous weight of the container is to be determined: Then, in the case of a common weighing of container and container receptacle, the generally known weight of the container receptacle must be deducted by calculation, which usually accomplishes a connected controller.
• Or - which is the more common case - it is an empty container brought to the weighing position, there first weighed the empty container to get a tare weight, and then in the weighing state, so with continuous further weighing, at the weighbridge the Filled containers. Since the controller is connected to the load cell, and simultaneously with the loader, the controller will terminate the fill operation as soon as the desired fill weight is reached, which is constantly determined from the difference in the current weighing result minus the known tare weight.

In this way, the filling weight can be achieved very precisely, and it is possible to dispense with an overfilling, that is to say an actual filling weight which is above the desired filling weight, as is necessary when e.g. Scatters from the weight of the container or the container intake must be compensated with, since only the total weight is determined.

In addition, when filling and the filling device is at least not moved in the horizontal direction, but then at most in the vertical direction, which is the probability of a filling material, which does not impinge in the container, but falsely outside of the container and a contamination and a later error Deflection can be very low.

In general, not only one container but several containers are weighed at the same time by a plurality of load cells are present in succession to the load cell in the direction of travel of the transport device, and are set to the distance to each other, the container or the container receptacles to each other on the transport device ,

Preferably, one or more packages are transported simultaneously on a transport device by means of individual transport carriages which are independent of one another, e.g. along a guideway, are movable, and with which the containers are transported before and after weighing and optionally additional filling to other processing stations such as closing, printing, packaging. Since these transport carriages can be moved independently of each other, different cycle times of the individual processing stations are easier to compensate for.

This procedure can be carried out with a device for weighing containers on a transport device, which on the one hand comprises the transport device with which the containers are transported, and on the transport device in particular also to the containers matching container receptacles.

Furthermore, the device comprises at least one weighing cell with a weighing surface at the weighing position, that is to say at a specific longitudinal position of the conveying device.

In this case, the weighing surface on the one hand and the transport device, in particular the container receptacle, on the other hand designed to be positioned and adapted to each other, either by lifting the weighing surface or by lowering the container, in particular together with the container receptacle, at least the container, preferably also the container intake, only weighs on the weighing surface and can be weighed by the load cell.

• So kann beispielsweise ein zur Seite hin offener Freiraum unterhalb des Gebindes, also zwischen der Transportvorrichtung und der Gebindeaufnahme, vorhanden sein, etwa indem die Gebindeaufnahmen zu einer Seite frei auskragen, aber sich immer noch im Ganzen innerhalb der Breite der Transportvorrichtung befindet. Die Wiegefläche der Wiegezelle kann von der Wiegezelle, die neben der Transportvorrichtung steht, zur Seite vorstehen in den Freiraum unter die Gebindeaufnahme hinein.
  Die Wiegezelle kann man auch so niedrig bauen, dass sie komplett in den Freiraum unterhalb der auskragenden z.B. Gebindeaufnahme passt, und sich damit die Wiegefläche auf der Oberseite der Wiegezelle befindet.
  Dies ist die kompakteste Lösung. Die Transportvorrichtung behält ihre ursprüngliche Breite bei und wird nicht verbreitert.
• Eine andere Lösung besteht darin, dass eine solche Gebindeaufnahme so weit einseitig auskragt, dass sie seitlich über die Transportvorrichtung vorsteht, und sich an der Wiegestelle über die Wiegefläche hinweg erstreckt, die neben der Transportvorrichtung angeordnet ist.

In order to make this possible, the weighing platform, if appropriate the entire load cell, is located below the container to be weighed. This can be achieved in different ways:

• Thus, for example, an open space to the side below the container, so between the transport device and the container receptacle, be present, such as by the container receptacles cantilevered to one side, but is still in the whole within the width of the transport device. The weighing surface of the load cell can project from the load cell, which is adjacent to the transport device, to the side into the free space under the container receptacle.
  The load cell can also be built so low that it fits completely in the free space below the cantilever eg container receptacle, and thus the weighing surface is located on the top of the load cell.
  This is the most compact solution. The transport device retains its original width and is not widened.
• Another solution is that such a container receptacle protrudes on one side so far that it protrudes laterally over the transport device, and extends at the weighing position on the weighing surface away, which is arranged next to the transport device.

In both cases, by pure vertical movement, the weighing surface can be brought into contact with the container or the container receptacle and weighed.

To shorten the cycle time, not only one, but several load cells are located in the direction of passage of the transport device at a weighing position one behind the other, and the load cells are adjusted to the distance that the products to be weighed currently take on the transport device to each other.

For this purpose, the load cells are continuously movable and fixable on a weighing base body in the longitudinal direction.

If the containers are also to be filled at the load cell, a filling device is also present at the load cell, for example a filling robot whose outlet openings can be positioned above the containers located in the weighing position or even within these containers.

The load cell as well as the filling device are then connected to a controller, which constantly receives the total weight of the weighbridge during the filling process, and deducted from the known tare weight, ie empty container and possibly the co-weighed container intake, the current filling weight calculated and Upon reaching the desired filling weight, the filling device controls so that the filling process at the right time, ie at the right actual filling weight, is terminated.

In this case, individual transport carriages which can be moved independently of one another along a guideway are preferably used as the transport device, so that a single transport carriage, e.g. carries a certain number of containers, depending on the work to be performed on a workstation for different lengths of the workstation can stop and can drive at different speeds between the individual workstations.

The guideway is preferably located on a track body having two or more guideways, preferably one for the forward direction of travel and one for the rearward direction of travel. The railway body is formed of individual Bahnkörpermodulen, with individual movable modules, in particular the Bahnkörpermodule at the beginning and at the end of the track body, can be relocated so that each of their guideways can optionally be brought into alignment with each guideway of the adjacent Bahnkörpermoduls, which is not movable in the rule.

For example, a cross-sectionally approximately rectangular web body on the top or bottom each have a guideway, and the movable web body module, the so-called inverter can be rotated by 180 ° about its longitudinal axis, so that a first arranged on the upper guide rail transport carriage thereafter this rotatable Bahnkörpermodul depends down and aligned with the lower track of the adjacent track body and can move on this.

As a rule, the overhead guideway is used as a forward guideway, in which the containers are also transported, while on the lower guideway on which the transport carriages hang, the empty transport carriages are transported back to the starting point. Of course, the transport carriages are designed in such a way that they do not fall off the latter when hanging on the lower guideway.

Regardless of lifting at least the container receptacle is possible on the upper guide track at least on the load cell by appropriate design of the guide rail and / or the transport carriage without the longitudinal drive device of the transport carriage relative to the guide path disengaged, so the transport carriage on its track not the longitudinal position changed.

The container receptacle is designed so that it then has the same position on the transport carriage by lifting and then lowering, as before.

Such a transport carriage usually consists of a guide member which is adapted to the guideway and in particular the guideway positively engages around, as well as a mounted on the guide member, but easily removable support member, which is adapted to the particular task, and either itself represents the container receptacle or a suitable container receptacle carries.

c) embodiments

Fig. 1a-c:

den Transportschlitten einer Transportvorrichtung,

Fig. 2a,b:

eine Wägeeinheit in perspektivischer Ansicht,

Fig.3a-c:

die Wägeeinheit in Aufsicht und Seitenansichten,

Fig. 4a, b:

das Zusammenwirken von Wägeeinheit und Transportvorrichtung.

Embodiments according to the invention are described in more detail below by way of example. Show it:

Fig. 1 a-c:

the transport carriage of a transport device,

2 a, b:

a weighing unit in perspective view,

3 a-c:

the weighing unit in top view and side views,

4 a, b:

the interaction of weighing unit and transport device.

As FIG. 4b shows, on the transport carriage 6 of the transport device 1 in the direction of passage 10 consecutively several, in this case eight, to be weighed container 20, in this case tubes 20, present at a location of the transport device 1, the weighing rack 9, weighed and usually also to be filled.

As in Fig. 1b shown, the transport carriage 6 has its own drive with a downwardly projecting pinion 16 (see FIG. 4 b ), which is in engagement with a rack 18 which extends in the direction of passage 10 along the guideway 7 a, on which the transport carriage 6 moves.

At the weighing rack 9, the transport carriage 6 cooperates with a weighing unit 12 , which stands next to the transport device 1.

First, based on the FIGS. 1a, b, c the structure of the transport carriage 6 described, the details best in the sectional view of Fig. 1b to recognize are:

The guide carriage 6 initially consists of a plate-shaped guide member 5, which runs on the guide track 7 a and this has the corresponding sliding shoes on its underside. In the longitudinal center of the guide member 5 , the downwardly projecting pinion 16 can be seen, which is driven by a motor, not shown in the transport carriage 6 and the passage along the guideway 7 a and the correct positioning of the transport carriage 6 in the longitudinal direction 10 causes.

At a distance above the guide member 5 is also a plate-shaped support part 4, each of which is adapted to the load to be transported. The support member 4 is held by spacers 15 at a distance from the guide member 5 , wherein the guide blocks 15 are outside the longitudinal center only on one side of the transport carriage 6 , so that from the other side, in the representation of Fig. 1b from the left, the space between the support member 4 and guide member 5 is freely accessible.

The support member 4 carries in this case in the longitudinal direction 10 in a row eight container receptacles 19, wherein in each container receptacle a not yet filled, at its rear end open and thus upwardly projecting tube 20 sits, which is to be filled. The container receptacle 19 is used in order to replace only the container receptacle 19 when switching to a new container, and not the entire support member 4, as well as for better ways to weigh the container 20:

Because the container receptacle 19 has three downwardly projecting centering cone 13 , each of which sits in a correspondingly shaped frusto-conical through hole of the support member 4 , so that the tips of the centering 13 protrude downward from the support member 4 and are connected there via a connecting plate 14 . Characterized is any container receptacle 19 on a three-point bearing in the supporting member. 4

If you push the connecting plate 14 upwards, and then let them fall again, the centering cone 13 will first lift off their frustoconical recordings and load the full weight of the container receptacle 19 including the container 20 received therein on the connecting plate 14 .

If the connecting plate 14 is then lowered again, the centering cones 13 and thus also the container 20 are centered again in their original position in the frustoconical through openings in both transverse directions, and the container 20 is reliably again in the longitudinal and transverse direction at the same relative Position to the support member 4 as before the pushing up of the connection plate 14th

How best that Fig. 1c shows, the individual container receptacles 19 are mounted with their connecting plates 14 each independently and at a distance from each other in the support member 4 .

• Denn dadurch ist es möglich, die auf die richtige Höhe und die richtige Querposition eingestellte Wiegezelle 2 mit ihrer Wiegefläche 3 in den Zwischenraum zwischen Tragteil 4 und Führungsteil 5 des Transportschlittens 6 ragen zu lassen.

For weighing of the unit comprising container receptacle 19 and container 20 are respectively a load cell 2 is used, in which the weighing platform 3 is not located above the load cell 2, but to the side of the latter in one direction, ie transversely to the longitudinal direction 10, is cantilevered, as best seen in Fig. 4a seen:

• Because this makes it possible, set to the correct height and the correct transverse position load cell 2 with its weighing surface 3 in the space between support part 4 and guide part 5 of the transport carriage 6 protrude.

By ramping up the weighing platform 3, the weighing platform 3 push up the connecting plate 14, so that the overall weight of container receptacle 19 and container 20 only rests on the weighing surface 3, and this weight can be determined by the weighing cell. 2

• Die Wägeeinheit 12 umfasst ein kastenförmiges Gehäuse 21, welches über in der Höhe einzeln einstellbare Standfüße 22 auf dem Untergrund steht.

The load cell 2 is part of a weighing unit 12, as in the FIGS. 2 a, b and 3 a - c is shown:

• The weighing unit 12 comprises a box-shaped housing 21, which stands on the stand individually adjustable in height stand 22 on the ground.

Above the housing 21 is a weighing table 23 which is adjustable over at least two vertical punches 25 in its distance from the housing 21 .

On the weighing table 23 , two longitudinal guides 24 run along which the weighing cells 2 which are present on the weighing table 23 , in this case eight, are displaceable and fixable.

How best Fig. 4b shows, the weighing unit 12 is provided at the intended weighing 9 so next to the transport device 1 that the longitudinal guides 24 parallel to the direction of passage 10 of the transport device 1 , both viewed in the plan view and viewed in the side view.

In addition, the load cells 2 are distributed along the longitudinal guides 24 and positioned so that they occupy the same distance from each other as the container receptacles 19 on the transport carriage 6.

In height, the housing 21 is leveled by means of the feet 22 and adjusted to such a height that in the initial state, the weighing surfaces 3 protrude into the space between the support member 4 and guide member 5 without touching them, so neither on the bottom nor on the top the weighing surface 3. The weighing surfaces 3 extend to below the spacer blocks 15 facing the end edge of the connecting plates 14th

How best Fig. 3c shows, by means of a lifting device which is housed inside the housing 21 , and a lifting motor 26, a gear 27 and eccentrically mounted on a gear shaft lever 28 , the vertical punch 25 and thus the weighing table 23 with all weighing surfaces 3 by such a degree be raised, that on each of the weighing surfaces 3, the total weight of each container receptacle 19 loads together with 20 containers.

In each of a weighing cell 2 associated electronics 30 , the result is processed and forwarded to a controller 17 in real time.

• Zu diesem Zweck befindet sich an der Mess-Stelle 9 - wie in Fig. 4a dargestellt - oberhalb der oben offenen Tuben 20 jeweils eine Auslass-Öffnung einer Befüllvorrichtung 11, wobei jede Auslass-Öffnung einzeln durch Ansteuern von der Steuerung 17 verschließbar ist.

Because usually not only the current weight of container receptacle 19 and 20 containers to be weighed, but by means of the load cells 2 , a correct filling process, ie a correct filling quantity, the container, in this case, the tube 20 can be achieved:

• For this purpose is located at the measuring point 9 - as in Fig. 4a shown - above the open-top tubes 20 each have an outlet opening of a filling device 11, wherein each outlet opening is individually closed by driving from the controller 17 .

After the empty tubes 20 are positioned by means of the transport device 1 at the measuring point 9 , therefore, the weight of the individual container receptacles 19 plus the empty tube 20 standing therein is first determined by lifting the weighing table 23 .

In this weighing state, that is, while we weigh continuously continued, then the filling of the tubes 20 is carried out from above, and as soon as the controller 17 for a single tube 20 communicated the exact reaching the filling weight of the electronics 30 of the corresponding load cell 2 is - calculated from the currently measured total weight minus the initially determined weight of container receptacle 19 and empty tube 20 - the filling process of this tube 20 is terminated by the controller 17 .

In this way, overfilling reliably avoided, which saves the manufacturer high additional costs.

LIST OF REFERENCE NUMBERS

1

transport device

2

Load cell

3

weighing surface

4

supporting part

5

guide part

6

transport carriage

7 a, b

guideway

8th

roadbed

8 a, b

Roadbed module

9

weighing station

10

Longitudinal direction, passage direction

11

filling

12

weighing unit

13

centering

14

connecting plate

15

spacer block

16

pinion

17

control

18

rack

19

Container Recording

20

Container, tube

21

casing

22

stand

23

Wägetisch

24

longitudinal guide

25

vertical temple

26

Lifting motor

27

transmission

28

lever

30

electronics

Claims (15)

A method of weighing containers (20) located on a transport device (1) by: - Approaching a weighing cell (9) with the container to be weighed (20) by means of the transport device (1), marked by Positioning a weighing surface (3) of a load cell (2) under the container (20) located on the transport device (1 ), - loading the container (20) on the weighing surface (3), - weighing the container (20) by means of the load cell (2). Method according to claim 1,
characterized in that
the loading of the container (20) on the weighing surface (3) is carried out by - either lifting of the container (20) by the transport device (1) by raising the cradle surface (3), so that the weight of the container fully rests on the weighing surface, - or lifting the container (20) from the transport device ( 1) by lowering the container (20), so that the weight of the container (20) completely on the weighing surface (3) rests, Method according to one of the preceding claims,
characterized in that
the position of the container (20) in the horizontal direction is maintained during lifting and weighing. Method according to one of the preceding claims,
characterized in that - The container (20) together with a container receptacle (19), in which it is located, is lifted, and / or - Several containers at the same time by one weighing surface (3) each have a load cell (2) are raised at the load cell. Method according to one of the preceding claims,
characterized in that
after weighing the empty container (20) in the weighing state, the container (20) to the cradle body (9) is filled thereby dad container (20) is weighed continuously, and the filling of fill weight transmitted in dependence of a control (17) is terminated. Method according to one of the preceding claims,
characterized in that
the weight determined by the load cell (2) is constantly reported to a controller (17) controlling the filling device. Method according to one of the preceding claims,
characterized in that
before starting the weighing operations, the weighing surfaces (3) of the load cells (2) are set to a distance in the direction of passage (10) of the transport device (1) , which corresponds to the distance of the container receptacle (19) on the transport device (1) . Device for weighing containers (20) on a transport device (1), with - A transport device (1), in particular has container receptacles (19) for containers (20) , a weighing cell (9) on the transport device ( 1), on which there is at least one weighing cell (2) with a weighing surface (3) , - wherein the cradle surface (3) and container receptacle (19) are adapted and positioned so that by relative movement of the weighing surface (3) to the container receptacle (19) the container (20) by the transport device (1) with its entire weight (on the weighing platform 3 ) . Device according to claim 8,
characterized in that
one or more containers (20) are moved by means of independently movable transport carriage as a transport device. Device according to one of the preceding device claims,
characterized in that - There are a plurality of load cells (2) on the weighing platform (9) which are adjustable in their distance in the direction of passage (10) of the transport device ( 1) to the distance of the containers (20) on the transport device (1). - the load platform (3) is located at the weighing point (9) each having a weighing cell (2) below a container receptacle (19) and by raising the cradle surface (3), the container receptacle (19) of the transport device (1) is lifted. Device according to one of the preceding device claims,
characterized in that - The container receptacle (19) in the transport device ( 1) and / or the container (20) in the container receptacle (19) are arranged self-centering in the horizontal directions. - The transport device comprises a plurality of transport carriages (6) which are independently movable on at least one guideway (7 a ) . Device according to one of the preceding device claims,
characterized in that - The transport device (1) comprises a support member (4) in which the at least one container receptacle (19) sits, and the support member (4) freely cantilevered to one side, and / or - The weighing surface (3) on the top of the load cell (2) and the load cell (2) is so low that it can retract under the support part (4) of the transport device (1) , and / or Device according to one of the preceding device claims,
characterized in that
the weighing surface (3) projects horizontally from the load cell (2) and the weighing surface (3) protrudes at the load cell (9) below the container receptacle (19), in particular below the supporting part (4), and in particular the load cells (2) when viewed in the supervision next to the transport device (1) are located. Device according to one of the preceding device claims,
characterized in that - The at least one guideway (7 a ) on a track body (8) is formed, which has at least two extending in the same direction guideways ( 7 a, b), in particular on opposite sides of the sheet body, such as top and bottom, and / or - the sheet body (8) in the direction of passage (10) adjoining track body modules (8 a, b), and at least one of the sheet body modules (8a) is so displaced that each of its guideways (7 a, b) in alignment Position to each of the guideways of the adjacent railway body modules ( 8 b) can be brought. Device according to one of the preceding device claims,
characterized in that - At the load cell (9) a filling device (11), in particular a filling robot, is present, and / or - each weighing cell (2) is connected to a controller (17) which is constantly communicated measured by said weighing cell (2) weight, and the controller (17) to the filling device (11) is connected to and controls.

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