EP0856465B1 - Tray conveyor moving in the opposite direction to the picker system - Google Patents

Abstract

The production line has a first storage surface for the single products (2), and a second storage surface for the containers (3). At least one pick-up device (4a,4b) transfers the single products from the first storage surface to the containers. The first and second surfaces, in the form of conveyor belts (6,7), move in contra-flow. The speed of the first and second surfaces is controlled in relation to each other. A first camera scans the entire width of the products-belt and is connected to a calculator(11).

Description

The invention relates to a picker line, as used to implement Individual products can be used in containers that have a certain number of Can record individual products.

The individual products are usually on a product line and the containers are delivered on a container belt and in a fixed position guided pickers along.

So far, it has been done so that the container on a first Container belt was delivered and mostly accumulated there, from the first Container belt were transferred to a second container belt on which the filling was done with the individual products, and after complete filling on a third container belt for the removal of the filled containers was passed again.

Furthermore, DE 42 08 818 C2 already shows an insertion device of products in containers, the products being delivered irregularly and can be inserted into the containers by means of pickers. However, it is not a picker line in the sense of the present invention, that is with several pickers one behind the other that can be moved independently, but two pickers mechanically coupled in their movement. Furthermore, the special advantage of the counterflow of Direction of delivery of products on the one hand and containers to be filled on the other hand recognized.

Furthermore, a picker line is known from EP 0 749 902, in which The container belt and the product belt run in parallel, side by side are, the containers are jammed, and a line scan camera in front of the Picker route The number and position of the products on the product belt determined. From this document is known according to claim 7 there, the container belt to run so fast that in time the one on the container belt located container needed to go through the work area, straight on the product belt, a filling number of individual products within the gripping range of the Pickers reaches or leaves. A control depending on the complete Filling of containers by the last picker in the direction of the container shows this writing just as little as a counter rotation of the container belt and Product tape.

In addition, control engineering measures can be taken if the Product belt to container belt are used, not on the counter-rotating principle transferred because there the thinning of the products on the Product band on the one hand and the degree of filling of the containers on the Container belt, on the other hand, run in reverse to each other.

It is therefore the object according to the present invention, a method and to create an associated device, in which the effort for the handling of the containers to be filled is reduced without the efficiency of the Facility to deteriorate.

The following is a solution with the same running direction of the container and described individual product that is not the subject of the present Is patent and serves only for explanation:

By arranging a counter for the individual products on the product line At the beginning of the picker area it is possible to always empty the container to release and drive into the area of the picker, if a filling number of the individual products was determined. This is only one the only container belt required, with a stopper for accumulating the empty one Container which is controlled by the counting device.

Preferably, the container belt is driven at the same speed as that Product belt, and preferably at a constant speed.

A particularly simple design results when the product band and Container belt are driven by a common drive, or can be combined into a one-piece conveyor belt, for example in the longitudinal direction separated by a standing wall in a transport area for the individual products and for the containers.

Depending on the position of the counter in the direction of transport compared to the Picker area and opposite the arrangement of the stopper on the - in the Rule parallel to the product belt - running container belt becomes a time offset intended for the release of the next empty container to the filling container approximately parallel to the products intended for it to transport the product belt.

It can completely fill a container with just one picker take place, or - depending on the running speed and the density of the Individual products per unit length of the product belt - over several in Direction of transport along the belt arranged picker.

The counting device is preferably a line by line scanning camera, preferably with a CCD sensor, the scanning line extends across the product belt, preferably at right angles.

It is already known from the prior art, the picker (s) to connect on the one hand with a computer and on the other hand with a image-recording unit, for example a CCD camera, here again with a line scan camera, the recording area across the Product band runs.

With the help of this line camera for the control of the picker is during the Passage of the product belt at a defined point, namely that of line scanned by the camera, the position of each in front of the picker area individual product on the product line and its location determined, and in Calculator taking into account the transport speed of the products and the distance between the scanned line and the picker position further processed to pinpoint the picker for gripping the individual products and transfer to the container including the necessary rotation of the Product control.

In the present case, the first camera can preferably be used for counting the Individual products arriving on the product line to control the Container feed on the one hand and the second camera for controlling the picker on the other hand, can be combined in a single camera, provided that this is arranged sufficiently far before the start of the picker area to a timely release of the next container on the container belt enable.

In addition to the counting device for the products and the Stopper for the delivered empty containers also all existing ones Picker of a product band via a data bus with the control computer connected so that from the originally from the camera to the picker control positions and orientations of the individual products the product volume is updated, which individual product has already been implemented by the picker.

This means that the next picker has to be at the start of each new work area Control of this picker is known in which originally occupied product positions there is still a product on the product belt.

This prevents empty movements of the picker and also empty filling processes on the container, the incompletely filled containers and carry out mechanical rework or committee.

If with the described procedure on the product belt various individual products are delivered randomly arranged in a jumble be by means of the counting device and by means of the camera for the Picker control can be distinguished and assigned in defined Positions of the containers are filled, the next one is released empty container only when the necessary for each container Minimum number of each variety of different products in the Containers should find receptacle that have passed the counting device.

However, this leads to the fact that - in contrast to the implementation of only one Kind of products of a product line - after filling the container that Product belt is not completely empty as the release of the containers is delayed which has to orientate itself to the comparatively rarest delivered product type.

With the help of the aforementioned method, it is also possible, for. B. only one product band on both sides of this product band in parallel Various container belts - separately or in one piece with the product belt executed - to operate. This is not only for such product tapes sensible, the high number of individual products per unit length transport, i.e. they are appropriately broadly trained and closely loaded, but also for reasons of the most efficient use of the picker:

If the entire system is connected to a common control computer or a data bus is connected to one another in terms of control technology it is possible to use one and the same picker not only for filling one but alternately use one or the other conveyor belt.

Especially when there are different individuals on the product line Products, it is also conceivable to use one of the two container belts with a maximum possible speed to run the other container belt on the other hand at a significantly reduced speed, so that the Containers of the second container belt, so to speak, as a buffer for the distributed differently on the product belt, different serve individual products. This results in an optimal degree of emptying of the Product range.

Another significant simplification in terms of construction and control can be achieved in that the container belt and the product belt not be moved in parallel, but in the opposite direction (as in the present Claims under protection). Theoretically, too crossing variants of product belt and container belt possible, albeit the parallel movement in the opposite direction is the most efficient form.

Due to the counterflow of containers and individual products, the initial counting of individual products and releasing the containers depending on Number of individual products counted.

The speed of containers on the one hand and individual products on the other relative to each other is only controlled so that no container The work area of the implementation leaves without being completely filled. In addition, the goal is to move in the opposite direction Product band no more individual products as soon as that Product range the implementation area, i.e. the work area of the individual or leaves the picker working in succession on the same containers.

Whether one of the speeds, e.g. B. is specified by the product belt, and then only the other tape at the current speed is controlled, or both bands are controlled so that the maximum Working speed of the picker working on it can be fully utilized may depend on the previous work steps that are carried out on the product belt or on the Container belt must be completed from. Whether both partial goals, on the one hand complete filling of all containers leaving the transfer area and complete emptying of the product belt at the same time, realizable at the same time depends, among other things, on whether there is only one type of product is present on the product belt and implemented in the container must, or whether several varieties are mixed on the product belt become. In this case, it is hardly possible to achieve both goals at the same time possible, unless the composition of the products on the Product belt according to the individual types can be controlled in terms of quantity, or there is no specific composition according to products within the Container necessary.

The advantages of such a counter-current operation are manifold: the costs for the creation of the system are reduced and the susceptibility to failure also, because this counterflow primarily means the number of required Photocells, for example at no longer available stopping points for the Containers etc. reduced to about a tenth of the need for the direct current principle becomes.

The control effort is also drastically reduced because the counting of the incoming individual products no longer exist before reaching the implementation area:

The relation of the speeds of the containers on the one hand and the individual products on the other hand, readjustments are made during the function as required, to only discharge completely filled containers from the transfer area. Depending on the route of implementation and thus the time required by the picker etc., this is also the case better optimization of the conversion performance possible if one of the belts, e.g. B. the product belt, specified at a constant speed must be driven. This is not possible with DC operation.

Another advantage is that transport chains, ie means of transport in which the containers are at fixed intervals the means of transport are arranged, can be used.

Other functional advantages are that - in the direction of the container considered - always a vacancy at the beginning of the implementation area so-called "nest" is available in the container, and towards the end of Implementation area - especially if different on the product line Products are delivered mixed, the probability is greatest is that a single product just needed in the work area Direction of the container of the last picker is located. So that's the probability extremely low that a not completely filled container Leaves the implementation area or a necessary slowdown or Stopping the container belt can be reduced to a minimum.

If the containers are arranged at fixed intervals and therefore at fixed intervals Ideally, positions of the container belt is not a photocell at all Checking the container and checking whether there are certain nests in the container are free, necessary because starting from the fixed existing Empty positions at the beginning of the implementation area by the system control is known at which position - both relatively within a container as also absolutely along the container belt - a free nest for which kind of Individual products are available.

Countercurrent operation is therefore particularly suitable for use together with two-armed robots as pickers.

Fig. 1:

eine Aufsicht auf eine Pickerstraße gemäß dem Stand der Technik im Gleichstrombetrieb, und

Fig. 2:

eine Aufsicht auf eine Pickerstraße im Gegenstrombetrieb.

An embodiment according to the invention is described below with reference to the figures. Show it:

Fig. 1:

a supervision of a picker line according to the prior art in DC operation, and

Fig. 2:

a supervision of a picker road in counter-current operation.

In Fig. 1, a picker line 1 is shown in the top view, which is in the running direction 20, from left to right, individual products 2 that are arbitrarily on one Pass through product belt 6 arranged under pickers 4a, b.

As shown in the left half of the figure, run parallel to the product belt 6 on container belts 7a, b empty containers 3 parallel to the product belt 6.

Before the first picker begins, one is passed across the product belt 6 running line scanned by a first line camera 8. The Line camera 8 is like each of the pickers 4a, b with a central one Controller 11, which comprises a computer, connected.

On the container belt 7, the empty containers 3 are transported and by means of a stopper 17 running across the container belt 7, against which the foremost empty container bumps. The stopper 17 is also connected to the controller 11.

The first pent-up empty container 3 is always released, as soon as such a number of under the first line camera 8 Individual products 2 has passed through on the product belt 6, as is the case Filling number of a container 3 corresponds.

So that the next container 3 to be filled with these individual products 2 the release runs approximately parallel to the products 2 intended for him preferably the first line camera 8 or its scanning line approximately the height of the rear edge of the foremost jammed, at the stop 17 adjacent, container 3 are located or even in the direction of 20th set back to the container approximately in the middle of the longitudinal area of the To let product tape 6 run in parallel, in which the corresponding Products lie.

Since preferably the container belt 7 about the same speed as the product band 6 has, is in the right half of the figure with a solution one-piece product and container belt shown.

The pickers 4a, 4b are - as is known per se - mostly with one over at least the product belt 6 extending, bridge-like base frame formed on which the picker arm 5 is articulated.

The picker arm 5 usually consists of an upper arm 13a, b via a shoulder joint 15 on the base frame by an essentially vertical axis is pivotally attached.

At the free end of the upper arm 13a, 13b, there is a forearm 12a, 12b also in turn fastened pivotable about an approximately vertical axis. The The forearm 12a, 12b is moved via a forearm parallelogram 14a, 14b, one parallel strut of which the upper arm 13a, 13b represents.

A sucker 16 is attached to the free end of the forearm 12a, 12b, the - after activation of a defined position in the horizontal plane through the control 11 - to an individual product 2 located there lowered, this then lifts and into the container 3 after rotation by one vertical axis according to the desired, correct orientation lowers.

So that the sucker 16a, 16b of the picker 4a the individual positions on the know the constantly moving product belt 6 that must be started up, is by means of a second line camera assigned to the first picker 4a when passing through the individual products 2 under the scanning line of these Line camera 10 any position at which a single product 2 is located registered and the rotational position of the individual product, and in the controller 11 saved as well as taking into account the belt speed in the Practice is not always constant, calculated further.

Furthermore, the control 11 detects what has already been removed from the product belt 6 Individual product 2 also taken into account, so that each still existing and to be implemented products from the subsequent picker movements or subsequent pickers 4b, etc. can be implemented.

In a preferred embodiment, the first line camera 8 does not register only the number of individual products passing under it 2, but - instead of the second line camera 10 - its orientation and immediately Position, so that only a single line scan camera is necessary.

A separate container belt 7 has the advantage that its speed Regardless of which of the product volume 6 can be regulated:

For example, the container belt 7 can be moved faster than that Product belt 6, so that in the area of the picker 4a, b, the container 3 them overtake assigned individual products 2.

As long as the differential speed is not too high, so that the overtaking process So it’s not over before the area of the only one or the area of the entire filling of the container has passed through the required picker the faster running of the container belt a desired quick removal of the completely filled container.

Separate container belts 7a, b can also be used to - as in the shown left part of the figure - two separate container belts 7a, b on both sides the product belt 6 to run on which there are different Containers 3 or containers to be filled differently.

Likewise, the container tapes 7a, b can also be different from one another Speeds run so that the one product belt 7a primary is to be filled while the second, slower running product belt 7b than Buffer if there are not enough empty containers on the first one Conveyor belt serves or - what z. B. with different on the product belt 6 incoming individual products 2 the case is - these individual products are not in the correct quantity relation to each other.

A further possibility is to use line scan cameras 8, 10 not only to have the area of the product belt 6 scanned, but also the area of the container belt 7, and the stopper 17 for the container belt 7 in the direction of travel only after the scanning line of the corresponding line scan camera to arrange:

This makes it possible, for example, to have different on the container belt 7 randomly arriving containers 3, or their different To grasp orientation or their different, partially filling, which makes the picker line particularly flexible to use.

2 run - in contrast to the 1 - the product belt 6 and the container belt 7 in the opposite direction parallel to each other.

There is no longer a line scan camera for counting the products, and usually also no stop for damming the container 3 on the Container belt 7, of which there are two container belts in Fig. 2, which are parallel and in the same direction are moved, there on both sides of the product belt 6. However, the two container belts 7a, 7b do not have to be the same Speed are driven. Only on the upper container belt 7a Motor 19 shown, which also with the controller 11 of the system in Connection is established, and its speed and thus the transport speed the container on this container belt is regulated accordingly.

As an alternative to a central controller 11, the speed of the Container belt 7 - in relation to that at a given speed running product belt 6 - through in the running direction 21 of the container belt 7 last picker 4a or its separate control can be controlled:

As soon as the control of this picker 4a recognizes that there is a risk that an incompletely filled container could leave the transfer area, the control of this picker 4a causes the speed to be reduced of the container belt 7. Should this - in the running direction 20 of the container belt 7 last - Picker 4a fail, the last one takes over this function Functional picker 4b.

Even at irregular intervals the container 3 is on a container belt it is sufficient, only the speed of this container belt and not also the relative distance between the containers on the container belt Taxes:

Because if to fill the container shortly before leaving the Conversion area, that is to say by the last picker 4a in this direction the container belt z. B. 7b temporarily reduced in speed must, this only means that those containers 3b, 3c that are in Direction of travel of the container belt 7 in the working area of the previous pickers 4b, 4c are to be filled to a higher degree, and thus on one earlier point within the implementation area are completely filled.

The controller 11 thus controls the speed of the container belts 7a, 7b and usually also the working speed of the pickers 4a, 4b, 4c - die Speed of the product belt 6 is mostly due to the production of the individual products delivered on it are predetermined - in such a way that the implementation area, thus the gripping area of the container belt 7 in the direction of travel 21 last pickers 4a leaving container z. B. 3a just completely can be filled. This makes the system's efficiency optimal exploited, and with sufficient working speed from the picker 4a, 4b can - if only one type of individual products 2 on the Product tape 6 is delivered - can be achieved that at the right end of Fig. 2, that is, when leaving the product belt 6 in its running direction 20 and Run out of the area of implementation of the last one in this direction Pickers 4c no longer have individual products 2 on product belt 6 are after the density of the individual products 2 during the run of the transfer area, that is, the working areas of the pickers 4a, 4b, 4c constantly has decreased. Should individual products still exist in the implementation area are present, they will be placed in a circle in front of the transfer area on the Product volume 6 returned.

This procedure can also be used with only a single picker 4 be, so that the implementation area exclusively from the work area of this single picker.

The principle of operation can also work with the product belt running at an angle to one another 6 and container belt 7 are applied as long as the crossing area is large enough, although through this crossing and thus in different ways Running and covering each other of the individual transport units Disadvantages have to be accepted.

REFERENCE SIGN LIST

1

Pickerstrasse

2nd

Single product

3rd

container

4a, 4b

Picker

5

Picker arm

6

Product tape

7

Container belt

8th

1. Line camera

9

Stop

10th

2. Line camera

11

control

12th

forearm

13

upper arm

14

Forearm parallelogram

15

Shoulder joint

16

Mammal

17th

stopper

19th

engine

20th

Direction of product belt

21

Direction of movement of the conveyor belt

Claims (14)

1. Method for placing individual products (2) into containers (3) which accommodate a particular filling quantity of individual products (2) by means of a picker system, wherein the individual products (2) are conveyed irregularly and the position and rotational position of each individual product is determined in order to individually pick it up and displace it,
   characterized in that,

   the individual products (2) and the containers (3) are conveyed in counterflow,

   depending on the supply of the required number of individual products (2) the supply of the subsequent container (3) to be filled to the working area of the pickers (4a, 4b) is controlled.
2. Method for placing individual products (2) into containers (3) which accommodate a particular filling quantity of individual products (2) by means of a picker system, wherein the individual products (2) are conveyed irregularly and the position and rotational position of each individual product is determined in order to individually pick it up and displace it,
   characterized in that,

   the individual products (2) and the containers (3) are conveyed in counterflow,

   the supply of the containers (3) to be filled to the working area of the pickers (4a, 4b) is controlled by controlling the relative speed of the supplied individual products (2) to the supplied containers (3) by means of the control of the last picker (4a) located in the moving direction (21) of the container belt (7) such that only completely filled containers leave the working area of this last working picker (4a).
3. Method according to any one of the preceding claims,
   characterized in that
   the picking up of the individual products (2) and the placing into the containers (3) occurs with moving individual products (2) and containers (3).
4. Method according to any one of the preceding claims,
   characterized in that
   at a predetermined speed of the supply of the individual products the conveying speed of the containers and/or the working speed of the pickers is controlled such that the containers leaving the working area of the last picker (4a) located in the conveying direction of the container are just filled to completion with the corresponding products and that there are no individual products present any more on the conveying device for the individual products upon leaving the working area of the last picker (4c) located in the conveying direction of the individual products.
5. Method according to any one of the preceding claims,
   characterized in that
   at a predetermined speed of the supply of the containers the speed of the supply of the individual products and/or the working speed of the pickers is controlled such that the containers leaving the working area of the last picker (4a) located in the conveying direction of the container are just filled to completion with the corresponding products and/or that there are no individual products present any more on the conveying device for the individual products upon leaving the working area of the last picker (4c) located in the conveying direction of the individual products.
6. Method according to any one of the preceding claims,
   characterized in that
   upon starting the picker system at a predetermined speed of the supply of the individual products the speed of the supply of the containers is increased in accordance with the fact that the first container to be filled is not successively filled by all pickers working in series (4a, 4b, 4c) but only by the last ones, in particular by the last picker (4a), while the filling of the subsequent containers (3b, 3c, ...) is effected by an increasing number of the pickers working in series (4a, 4b, 4c).
7. Picker system for placing individual products (2) into containers (3) which accommodate a particular filling quantity of individual products (2), comprising

   a first storage area for the irregularly supplied individual products (2),

   a second storage area for the containers (3),

   means for determining the position and rotational position of each individual product (2),

   at least one picker (4 a,b) for individually displacing the individual products from the first storage area into the containers (3),

   control and driving devices for moving the first storage area, the second storage area and the picker base, respectively, relative to each other and

   control and driving means for the movement of the picker arm, in particular for performing the method according to claim 1 to 6,

   characterized in that

   the first storage area for the individual products (2) and the second storage area for the containers (3) are moved in counterflow to each other and

   the speed of the first storage area for the individual products (2) and of the second storage area for the containers (3), respectively, are controlled relative to each other such that the containers (3) are completely filled with individual products upon leaving the working area of the last picker (4a) located in the conveying direction (21) of the second storage area for the containers (3).
8. Picker system according to claim 7,
   characterized in that
   the control of the last picker (4a) located in the moving direction (21) of the container belt (7) controls the supply of the containers (3) to be filled by controlling the relative speed of the supplied individual products (2) to the supplied containers (3) such that only completely filled containers (3) leave the working area of this last working picker (4a).
9. Picker system according to claim 7 or 8,
   characterized in that
   the control of the last operating picker (4a) located in the moving direction (21) of the container belt (7) is a separate control of this picker (4a).
10. Picker system according to claim 7,
    characterized in that
    upon leaving the working area of the last picker located in the moving direction (20) of the first storage area for the individual products there are no individual products present any more on this storage area.
11. Picker system according to any one of the preceding device claims,
    characterized in that
    the first storage area for the individual products is a conveyer belt (product belt 6) and that the second storage area is also a conveyer belt (container belt 7).
12. Picker system according to any one of the preceding device claims,
    characterized in that
    the container belt (7) runs at such a speed that in the time that a container (3) present on the container belt (7) requires for passing through the working area of the picker or pickers (4a,b) a filling quantity of individual products (2) located on the product belt (6) is just reaching or leaving the picking area of the picker (4).
13. Picker system according to any one of the preceding device claims,
    characterized in that
    on the pickers (4 a,b) at least one device for recording the position of all individual products located on the product belt (6) as well as a control (11) taking into account the conveying speed of the product belt (6) and the position of the pickers is provided for controlling the pickers (4).
14. Picker system according to any one of the preceding device claims,
    characterized in that
    the device for recording the positions of the individual products (2) located on the product belt (6) comprises a line camera (10) scanning across the entire width of the product belt (6).

Images