GB2201647A

GB2201647A - Process and apparatus for placing articles in a packaging unit in predetermined alignment and position

Info

Publication number: GB2201647A
Application number: GB08803073A
Authority: GB
Inventors: Hans-Bernd Lesch
Original assignee: LESCH HANS BERND
Current assignee: LESCH HANS BERND
Priority date: 1987-02-12
Filing date: 1988-02-10
Publication date: 1988-09-07
Anticipated expiration: 2008-02-10
Also published as: DE3704423A1; CH675233A5; GB8803073D0; DD289503A5; NL8800217A; GB2201647B; IT8803326A0; IT1227144B

Description

2 22' 0 16 4 7 PROCESS AND APPARATUS FOR THE FULLY AUTOMATIC PLACING OF

ARTICLES, IN PARTICULAR SWEETS, IN A PACKAGING UNIT The invention relatps to a process and apparatus for the fully automatic placing of articles, in particular sweets, in a packaging unit, with predetermined alignment in identical positions. Such an apparatus is comprised of at least one feeding unit for the articles, conveying devices for transporting the articles to the placement station, as well as a placing device for transferring such articles from the conveying device into predetermined positions in the packaging unit.

With a known apparatus of said type, the articles are pushed from a tray onto a conveyor belt, pulled apart thereon with the help of spacing devices, and arranged in arow, so that finally, the articles can be transferred from wide segregating belts - on which they are disposed one after the other in defined positions - to a narrow feeding belt, on which the article disposed in the foremost position is, in each case, centered by a stop means and, from this exactly defined position, transferred and placed in the packaging unit by a mechanically driven.placing head by means of a sucking or gripping device. Sich an apparatus is necessarily afflicted with a number of serious drawbacks. For example, the placing head can be changed to another placement position only through costly mechanical resetting. In practical life, the resetting times for changing a packaging line with 20 to 40 placement heads may amount to several days, with negative effects on the packaging cost. Moreover, the site of placement of an individual placing arm with the sucking or gripping device supported thereon can be varied only within very narrow limits due to the process conditions involving mechanical resetting. No free selection of the 1 placement position is possible. Furthermore, on the segregating belts, the articles come into frictional contact with one another and with the lateral guides of the spacing devices and feeding belts, which may adversely affect the quality of articles with a sensitive surface such as, for example, sweets. Finally, reliable automatic segregation by means of spacing devices is not possible with certain outlines of the goods such as, for example, a triangular outline. on the other hand, in the prior art, the arrangement of the articles on the tray or on a conveyor belt onto which such articles are pushed from the tray - is registered by means of an optical system and analyzed by a computer. With the help of a robot, the articles are directly picked from the tray or conveyor belt and placed in their intended positions in the packaging unit. Even though such articles are carefully treated in such a system and their site of placement can be freely selected by pushbutton, such an arrangement, too, has unavoidable serious drawbacks. The automatic devices, if they are to selectively gain access to any position in the packaging unit, require an operating range having at least the size of the outline of the packaging unit. In practical application, a robot requires as its operating range about 1500 to 2000 mm of the distance over which the packaging unit is transported. This means that the placement lines, which may comprise.20 to 40 automatic article placement systems, are necessarily very long, which, in turn, is costly in terms of operating and control personnel requirements. Furthermore, the cycle time, i.e., the output of a placement line, is determined by the robot traveling the longest distance for placing the article. Consequently such robot represents the weakest link in the chain, for which the other automatic devices have to "wait". Optimization of the production output is, therefore, possible

7 1 only on conditions.

Recognizing the problems outlined above, the invention is based on the problem of further developing the process and apparatus of the aforementioned type in a way such that the articles can be fed to the placement device at high operating speed and safety, in a manner protecting such articles and with their correct positioning at predetermined intervals, while avoiding the drawbacks outlined above. According to the invention, said problem is resolved by the features specified in the claim, with reference being made to the features contained in the subclaims with respect to preferred embodiments.

According to the invention, the spatial position of the articles within the feeding zone is acquired mathematically, the articles are aligned in a predetermined way and transferred at regular intervals to a conveying system feeding such articles to the placement zone. Within the zone of the feeding unit, the apparatus has a detection system permitting the position and alignment of the articles to be determined, as well as an automatic handling device that is freely programmable in three axes, by means of which device the articles can be picked from the zone of the feeding unit, aligned in the predetermined position and deposited on the conveying deVice a regular intervals.

The detection system, which preferably is an optical position detection device, detects the spatial position and the position of the articles as the latter are being slowly passed beneath the system. Such position data are transmitted by the detection system to the computer of the control system of the handling device and the computer computes the optimal sequence of pick-up for the individual articles. The automatic handling device subsequently picks up the articles in the computed sequence, aligns such articles and deposits the latter on the conveying device always in the same spatial position, and the articles are then fed to the placement zone. Thus the article, as it is being transferred, is simultaneously turned into the position in which it is to be placed later in the packaging unit. For this purpose, the sucking or gripping device mounted on the automatic handling unit is supported rotatably. Usefully, the angle of rotation is adjusted by motor power in accordance with the data supplied by the detection system.

According to a preferred embodiment of the invention, the feeding unit consists of a slowly controiled feeding belt, onto which the articles are pushed from a tray. The articles are slowly passed -under the position detection system before being fed to the pick-up zone of the automatic handling device.

on the other hand, the feeding unit may consist of a conveying device for trays designed for depositing on a reservoir for the conveying device. Preferably, such a reservoir is a lift by which the trays are guided on. toothed belts for further conveyance, which toothed belts slowly pass the trays directly under the position detection system. Thus the handling device is capable of directly picking the articles from the trays.

Both embodiments assure protective handling of the articles, whose surfaces are not damaged either by frictional contact with one another or by bumping against the spacing elements.

The handling device always deposits the articles in a spatially fixed position on the conveying device, which is usefully located in the center of the belt. This considerably reduces the switching path or distance as compared to the placement robot, which directly places the articles in the packaging unit. The placement pro duction of the individual handling device and thus the output of a complete placement i 1 1 J line, therefore, can be significantly increased.

By using the narrow feeding belts, several placement devices can be combined to form compact product placement stations for a number of differently shaped articles. For example, in practical life, it is possible to design such a placement station for eight different individual articles, which station can be monitored and fed by one single operator.

The direct placement procedure, in which the articles are.picked from the conveying device and placed in the packaging unit, may be'accomplished by-means of conventional placement mechanisms. Suitable is, by way of example, a cam-controlled placement mechanism operating simultaneously with a number of sucking or gripping devices for several articles, as the narrow belts permit the articles to be closely brought together in the pick-up location. A suitable placement device is described in the European Patent Application 84.104.796.2. 'The placing heads described therein permit selective positioning of the goods in the packaging unit, which, in turn, permit building a completely flexible pro- -duct placement line.

According to another advantageous embodiment of the invention, the conveying device is provided in the form of a suction belt, with holes in the center line of the belt, such holes being arranged spaced from one another and connected with a vacuum rail supported beneath the belt. In this way, it is assured that the articles are prevented from turning or being displaced on the conveyor belt. On the lat ter, the articles are fed in their correct position, so that turning or rotation of the suction or gripping device on the placi ng head is not required.

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i Usefully, the suction belt is driven via a spike roller whose spikes engage the holes provided in the conveyor belt along its center line. Such formlocked engagement assures a positive belt drive and, at the same timep serves for cent ering as well as for keeping such holes free from dirt.

Each individual automatic handling device may be associated with two conveyor systems, which are fed simultaneously. This may be accomplished via an individual work cycle of the automatic handling system, or each of such conveyor systems may be equipped with two suction heads or gripping devices, which embodiment is to be viewed as another advantageous embodiment of the apparatus according to the invention.

Additional details, advantages and features essential to the invention can be derived from the following descr ' iption of one embodiment of the inv&ntion involving the placement of sweets by way of example only. Such embodiment is explained in greater detail by reference to the drawing, in which:

Fig. 1 shows a top view of an embodiment of the placing device according to the invention, with a schematic diagram of the individual placing heads; Fig. 2 is a lateral view of the device shown in Fig. 1, also shown in a schematic diagram; Fig. 3 is a top view of the placing device according to Fig. 1, with a multi-placement head; Fig. 4 is a schematic view of a placement station with eight placement units; Fig. 5 shows a vertical section through a conveying device designed as a suction belt; Fig. 6 is a front view of an embodiment of the feeding unit with a reservoir for the trays carrying the goods; and Fig. 7 is a lateral view of the reservoir shown in Fig. 6.

7 1 W 1 A Fig. 1 shows a combination of-three feeding units each being denoted in its en. tirety by reference numeral 10, which feedihg units serve the placement site by way of the four conveyor belts 11 to 14. According to one embodiment, the feeding unit is comprised of a slowly moving transporting belt 15r on which the articles, in the present case the sweets 16, are deposited in a manner not shown in detail, for example on trays. The sweets 16, which are disposed on the transporting belt 15 without any order, are slowly passed b.eneath gn optical position detection system 17 of the type sufficiently known with respect to its structure and mode.of operation.

The position detection system 17 is followed downstream by an automatic handling device 18, which is freely programmable in three axes. At the outer end of its arm, the automatic handling device 18 supports a sucking orgripping device 19 for handling the sweets 16. The position data are transmitted by the detection system to a computer - not shown in the drawing - of the control of the automatic handling device, and the computer computes the optimal sequence for the individual sweets. Subsequently, with its sucking or gripping device 19,.the automatic handling unit picks the sweets in the computed sequence from the slowly moving, controlled feeding belt and deposits such sweets in always constant spatial depositing positions on the conveyor belt 11 to 14 leading to the placement zone.

As they are being transferred, the sweets are simultaneously turned into the position in which they are to be placed later in the packaging unit, as this is shown in Fig. 1. For this purpose, the sucking or gripping device 19 is rotatably supported on the,automatic handling device 18. The angle of rotation is adjusted by a motor in accordance with 1 1 the data transmitted by the detection system.

Fig. 1 shows that the suitably rated automatic handling device 18 is capable of simultaneously feeding two transporting belts 11 and 12.

The conveyor belts 11 to 14 convey the sweets 16 to the placement location, where such belts meet with a conveyor unit 20 which continues to move the containers or trays 21 substantially at right angles in the direction indicaed by the arrow 22. The conveyor unit 20 comprises one or several chains 23 with stops or latch noses 24, against which the containers 21 rest in precisely defined positions.

In the embodiment shown, one-placement head 25 is associated with each conveyor-belt 11 to 14 in the placement zone. The placement heads 25 transfer the sweets 16, for example by means of cam-controlled suckers or grippers, from the conveyor belts 11 to 14 into the predetermined positions within the tray 21.

The transfer of the sweets 16 from the transporting belt 15 to the conveyor belts 11 to i4 by the automatic handling device 18, as well as the placement of the sweets 16 in the trays 21 may take place in each case during a brief stop of the conveyor belts 11 to 14.

Fig. 2 shows a side view of the apparatus, which is supported by a rack or frame 26. The suction device 27, which is guided by the placing head 25, transfers the sweets 16 from;-.the conveyor belt 11 to the container 21along the patb-of movement indicated by a dash-dotted line, such container 21 being supported by the chains 23 and passed on. The position detection system-17 detects the total width of the transporting belt 15 of the feeding unit 10. Fig. 2 shows only one feeding unit 10, however, one placement location or site may comprise, for example about eight conveyor 1 - 9 belts 11 to 14 with associated feeding units 10.

The conveyor belts 11 to 14 may be designed as suction belts, in the way explained in greater detail in the following by reference to Figs. 2 and 5. 1 A vacuum strip 28 having a U-shaped cross section and being connected with a vacuum system (not shown in the drawing) via a connection 29 is disposed beneath the conveyor belt 11. The latter is designed in the form of a toothed belt with a toothing 30 beneath the belt, such toothing being engaged by a driving unit. Along its center line, the belt 11 is provided at regular intervals with holes each forming a point of deposit for the sweets 16 for the automatic handling unit 18. The vacuum strip 28 is sealed at both face sides, so that a suction effect is acting on the holes 31 guided within the zone of the strip. Due to such suction effect, the sweets 16 are safely prevented from turning or sliding as they are being conveyed to the placement station.

Fig. 2 shows, furthermore, that the conveyor belt 11 is guided via a spiked roller 32 with the spikes 33 being spaced from one another along the circumference in a way such that their spacing conforms to the linear spacing between the holes 31 of the belt 11. The spikes 33 engage such holes and serve for driving and centering the belt 11.

By fully penetrating the holes, the spikes keep the latter free from dirt at the same time. If the spiked roller 32 is driven, the toothing 30 serving as a driving means can be dispensed with.

The apparatus according to Fig. 3 substantially conforms to the structure explained by reference to Fig. 1, so that no detailed description of the former -is required. A special feature of the device of Fig. 3, however, is a double sucking or double gripping device 34, with which one of the automatic handling devices 18 is equipped. Thus the latter

1 is capable of simultaneously serving two conveyor belts 11 and 12.

Another special feature of the.embodiment shown in Fig. 3 is a multiplacement head.35, which, controlled by cams, is. capable of placing the sweets 16 supplied via the conveyor belts 11 to 14 in the container 21 with exact positioning of such sweets.

rig. 4 shows a schematic view of a placement station in which, in a spacesaving way, eight conveyor belts 11 to 14 and 36 to 39 are associated with one'placement location. Said conveyor belts-are grouped around a work station 40, so that one operator is able to monitor and feed this product placement station with eight feed lines. 'Such station may be equippped with the individual placement head 25 or multi-placement heads.

Another embodiment of the feeding unit is shown in Pigs. 6 and 7. The optical detection system 17 and the automatic handling device 18, which transfers the sweets 16 to the conveyor belt 11, conform with the embodiment described in the foregoing. However, instead of the feeding belt 15, the present embodiment has the conveyor chains 41, which pass the tray 43 with the sweets 16 disposed on such tray which tray was directly picked from a reservoir 42 slowly under the detection system 17. The reservoir 42 is designed as a lift. The trays 43 rest on angular straps 45 supported on vertical belts. When needed, the vertical belts 44 are put into motion and advance in the direction shown in rig. 7 by the arrows 46, and the next tray 43 is deposited on the conveyor chains 41., Thus an overall space-saving product placement apparatus is obtained that is capable of operating at high speed and high functional safety.

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Claims

CLAIMS:

1. Process for the fully automatic placing of articles, in particular sweets, in a packaging unit with predetermined alignment and in identical positions, characterized in that in the feeding zone, the spatial position of the articles is mathematically acquired, the articles are aligned in a predetermined wayand transferred with regular spacings to a conveying system feeding such articles to the placement zone.

2. Apparatus for carrying out the process defined in claim l,' with at least one feeding unit for the articles, conveying devices for transporting the articles to the placement location, as well as with a placing device for transferring the articles from the conveying device into predetermined positions in the packaging unit, characterized in that within the zone of the feeding unit. provision is made for a detection device by means of which the position and alignment of the-articles.-i are determinable, as well as for an automatic handling device,..the latter being freely programmable in three axes and capable of picking the articles from the zone of the feeding unit, aligning such articles in the predetermined direction and depositing the latter with regular spacings on the conveyor device.

3. Apparatus as defined in claim 2, characterized in that the detection device consists of an optical position detection system,

4. Apparatus as defined in claim 2, characterized in that the feeding unit moving, controlled feeding belt.

comprises a slowly

5. Apparatus as defined in claim 2, characterized in that the feeding unit system. 1 for trays on the conveying system consists of a conveying designed for depositing. from a reservoir.

a h I--

6. Apparatus as defined in claim 5, characterized in that the reservoir is designed as a lift.

7. Apparatus as defined in claim 2, characterized in that the conveying system is designed as a suction belt with holes centrally arranged therein with regular spacings between one another, and connected with a vacuum strip arranged beneath the belt.

8. Apparatus as defined in claim 7, characterized in that for driving the suction belt provision is made for a spike roller, the spikes thereof fully engaging the holes of th& conveyor belt.

9. Apparatus as defined in claim 2, characterized in that two conveyor devices are associated with the automatic handling device.

10. Apparatus as defined in claim 2, characterized in that the automatic handling device is equipped with two suction heads or gripping devices.

11. A process for automatically placing articles in a packaging unit with predetermined alignment and in identical relative positions substantially as hereinbefore described with reference to Figures 1 and 2, or 3 or 4 alone or as modified by any one of Figures 5 to 7 of the accompanying drawings.

12. Apparatus for automatically placing articles in a packaging unit with predetermined alignment and in identical relative positions substantially as hereinbefore described with reference to figures 1 and 2 or 3 or 4 alone or as modified by any one of Figures 5 to 7 of the accompanying drawings.

Published 1988 at The Patent Office, State House, 86171 High Holborn, London WC1R 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3F.D. Printed by Multiplex techniques ltd, St Mary Cray, Kent. Con. 1/87.