WO2012047153A1

WO2012047153A1 - A system and arrangement for collecting packages

Info

Publication number: WO2012047153A1
Application number: PCT/SE2011/051168
Authority: WO
Inventors: Staffan LINDÉN; Ulf Mossberg; Jimmy Liljenberg
Original assignee: Tetra Laval Holdings & Finance S.A.
Priority date: 2010-10-05
Filing date: 2011-09-30
Publication date: 2012-04-12

Abstract

A transport system (100) comprising a conveyor belt (101) for conveying objects (102), a transport device (103) comprising a number of carrier elements(104) for carrying an object (102) each, is provided- The transport device (103) is placed next to said conveyor belt (101), such that said object(102)can be fed from said conveyor belt (101) to said transport device(103). A first sensor (106) for detecting said object on said conveyor belt(101), and a controller, configured to regulate a motion of said transport device(103)based on data from said first sensor,are provided, such that said object is timely received by one of said number of carrier elements(104).

Description

A SYSTEM AND ARRANGEMENT FOR COLLECTING PACKAGES

TECHNICAL FIELD

The present invention pertains to a system in a packaging machine for transferring packages from a conveyor belt to another packaging machine unit, said system comprising a conveyor belt, a guide bar, and a transport device in the end of the conveyor belt. TECHNICAL BACKGROUND

In the packaging industry, such as the industry for packaging food products, packages, such as packages with tetrahedral shape, are transported on different conveyors between filling and packaging units. In these instances there is a problem in package handling, owing to non-symmetrical flow of products and optionally in combination with shapes of packages being difficult to handle in a regulated way. Also, as in all manufacturing processes, time is of the essence. It has therefore hitherto been difficult to obtain an efficient handling process of packages, and specifically packages with tetrahedral shapes.

Previously, this problem was aimed to be solved by dividers, dividing a flow of packages into two separate flows, whereby the collectors at the end of the flows would get more time to handle the individual packages, thus alleviating the high capacity demands. However, the divider becomes a function that requires high functionality. Also, flow irregularities still needs to be addressed downstream in the system, in between the collector and the divider, and somewhere downstream, the divided streams of packages either has to be separately treated all the way to final packaging in secondary packages, or the divided streams once again has to be reunited into a singular stream, to allow for a single final packaging operation into secondary packages.

Furthermore, when the packages have a tetrahedral shape, the handling is further complicated, due to the irregular shape.

Hence, a new system for handling packages in a packaging machine would be advantageous, and especially a system allowing for reduced cost, higher capability, better functionality, and specifically suitable for packages with tetrahedral shapes.

SUMMARY OF THE INVENTION

Accordingly, the present invention preferably seeks to mitigate, alleviate or eliminate one or more of the above-identified deficiencies in the art and disadvantages singly or in any combination and solves at least the above mentioned problems e.g. by providing a transport system comprising a conveyor belt for conveying objects, a transport device comprising a number of carrier elements for carrying an object each, said transport device being placed next to said conveyor belt, such that said object can be fed from said conveyor belt to said transport device, a first sensor for detecting said object on said conveyor belt, and a controller, configured to regulate a motion of said transport device based on data from said first sensor, such that said object is timely received by one of said number of carrier elements.

Further advantages and preferred embodiments will be apparent from the dependent claims.

BRIEF DESCRIPTION OF DRAWINGS

These and other aspects, features and advantages of which the invention is capable of will be apparent and elucidated from the following description of

embodiments of the present invention, reference being made to the accompanying drawings, in which

Fig. 1 discloses a schematic top view of an embodiment of the present invention; and

Fig. 2 discloses schematic top view of another embodiment of the present invention,

Fig. 3 discloses a perspective view of two carrier elements according to another embodiment of the invention,

Fig. 4 discloses a schematic top view of the embodiment in Fig. 3, and

Fig. 5 is a schematic view from the side of a conveyor belt configuration according to one embodiment of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Several embodiments of the present invention will be described in more detail below with reference to the accompanying drawings, in order for those skilled in the art to be able to carry out the invention. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Fig. 1 illustrates a transport system 100 according to one embodiment of the present invention. The transport system 100 comprises a conveyor belt 101. The conveyor belt 101 is adapted and arranged to convey an object 102, such as a package, along its longitudinal extension. The conveyor belt 101 transports the packages towards a transport device 103. The transport device 103 transports/transfers the packages from the conveyor belt 103 to another conveyor belt or packaging machine unit (not shown) along a transport path. The transport device 103 may be a transferring wheel, with carrier elements 104, such as transferring slots, corresponding to the shape of the packages to be transported/transferred to another conveyor belt or packaging machine unit. The transport device 103 may also be a chain or belt with carrier elements 104, 114 having transferring slots 114d (Fig. 4), corresponding to the shape of the packages to be transported/transferred to another conveyor belt or packaging machine unit, said chain or belt optionally being an endless chain or belt, running on drive gears or wheels, see also Figs 3 and 4.

When the packages 102 reach the end of the conveyor belt 101, they enter the carrier elements 104, having transferring slots 114d. When the transport device 103 is a transferring wheel, the packages are rotated in the transferring slots over to another conveyor or machine unit. The transport device 103 moves perpendicular to and transversally of the transportation direction of the conveyor belt 101, from a first longitudinal side of the conveyor belt 101 to a second longitudinal side of the conveyor belt 101. Then, the carrier elements 104 sweep in the horizontal plane, in a direction substantially perpendicular to and transversally of the direction of transportation of the conveyor belt 101. Thus, when the packages are transported from the conveyor belt 101 to the transport device 103, they are moved transversally to another package machine unit along a transport path that might be straight, circular or any other shape. When the transport device 103 is a transferring wheel with transferring slots, the transferring wheel may rotate, such that packages are (i) picked up at the end of the conveyor belt 101, (ii) dropped off at another position, and (iii) thereafter the transferring slots are returned to the end of the conveyor belt 101. When the transport device 103 is a transferring wheel it is specifically suitable for picking up tetrahedral packages, since the transferring slots most suitably will have a triangular cross section, which are rotated around the central axis of the transferring wheel, said triangular cross section then being adapted in relation and according to the cross sectional triangular area of the tetrahedral packages.

The packages 102 are aligned on the conveyor belt 101 by a guiding bar 105. The guiding 105 bar serves the purpose of aligning the edge of the package with the transportation direction of the conveyor belt 101, such that the aligned edge is closer to the first longitudinal side of the conveyor belt lOlthan the second longitudinal side of the conveyor belt 101.

As disclosed in Fig. 2, the guiding bar 105 has a package aligned zone 105a upstream the transport device 103 and a package alignment zone 105b upstream the transport device 103 and the package aligned zone 105 a, in relation to the transportation direction of the conveyor belt 101. In the package aligned zone the guiding bar 105 is arranged to be substantially parallel with the direction of transportation of the conveyor belt 101. In this way, an already aligned package in the package alignment zone may be kept aligned with the guiding bar 105.

The packages 102 are aligned along the guiding bar 105 by the aligning zone

105b by arranging the guiding bar in the transportation path of the packages 102, such that the guiding bar 105 pushes the packages in a direction perpendicular to the transportation direction, until the packages subsequently align an edge of the package along the aligned zone 105a. This may be obtained by gradually forcing the packages into said aligned position with an S-shaped guiding bar 105 or a slightly slanted guiding bar from the first side of the conveyor belt 101, slanting medially.

When the packages have a tetrahedral shape, this arrangement of the guiding bar 105 is highly beneficial, since said shape inherently will ensure that the rearmost part of the package will be the rearmost end of the aligned edge. In this way, as soon as the rearmost end of the aligned edge has been displaced towards the second side of the conveyor belt by a first carrier element 104 of the transport device 103, the next package may freely enter a second carrier element 104 of the transport device. In this way, the distance between the packages may be decreased, while still allowing a controlled transfer of the packages from the conveyor belt 101, via the transport device 103, to a second conveyor belt or packaging machine unit.

The carrier element 104 may for example be transferring slots in a transferring wheel, according to above. When the carrier elements 104 are transferring slots in a transferring wheel, the transferring slots comprise an upstream wall 104a and a downstream wall 104b, as disclosed in Fig. 1. When the package 102 enters the transferring slots, the upstream wall 104a will drag the package 102 towards the second longitudinal side of the conveyor belt 101. To further increase the preciseness, and allow for an even decreased distance between the packages on the conveyor belt 101, the upstream wall 104a should be extending in a plane substantially parallel with the aligned edge of the package 102 and the extension of the guiding bar 105 in the aligned zone 105a, and substantially coinciding with said edge and guiding bar, when the transferring slot is in its dragging position, i.e. the position in which the upstream wall 104a contacts the package and the aligned edge thereof.

Upstream the package conveyor belt 101 a first sensor 106, a position sensor, may be arranged for detecting a package passing a first point. Said position sensor 106 may for example be a photo cell. A second sensor 107, such as a conveyor speed sensor or package speed sensor, may also be arranged along the conveyor belt 101 , to detect the speed of the packages v_p on the conveyor belt 101 , the speed of the packages being the same as the speed of the conveyor belt 101. The conveyor speed speed sensor 107 may for example be a rotating encoder. When a package passes the position sensor 106 a controller/regulating unit (not shown), such as a shift register, is informed, said regulating unit optionally simultaneously registering the speed of the conveyor belt 101 and thus the package by the speed sensor 107. The controller/regulating unit now knows the position of a package and the speed thereof this will trigger a calculation of the regulating/rotational speed of the transport device 103. All data is put into a shift register. From the obtained information from the position sensor 106 and the speed sensor 107, knowing the distance from the position sensor 106 to the transport device

103 it is now possible to calculate the actual distance between the packages close to the package collector, and how the transport device 103 should adjust its carrier elements

104 according to the flow of packages on the conveyor belt 101 , to ensure that a carrier element 104 will pick up a package when said package leaves the conveyor belt 101.

Thus it is possible to position a carrier element 104 in a position that will open up immediately after a prior package has been moved transversally. In other words, the next arriving package will not hit the walls 104a, 104b of the carrier element 104, until the package fin enters the open corner of a subsequent carrier element 104. For the above embodiment, it is important to time the speed of the transport device such that a constant clearance gi is achieved between the outward edge of the downstream wall 104b and the package 102.

Another embodiment of the invention can be seen in Figs. 3 and 4. Here, the carrier elements 1 14 are created with a wedge-shaped slot 1 14d, which is formed by two angled walls, an upstream wall 1 14a and a downstream wall 1 14b. The wedge-shaped slot is further provided with a groove 1 14c where the two walls 1 14a, 1 14b meet, in order to accommodate a front fin 102a of the package 102 to be conveyed by the transport device. The angled walls 1 14a, 1 14b of the carrier elements 1 14 are symmetrically arranged in relation to a back wall 1 14e, where the carrier element 114 is attached to a chain 120. An angle between a line that is perpendicular to the back wall 114e and the upstream wall 114a is denoted a. This embodiment is also configured to work in cooperation with the guiding bar 105 that can be seen in Fig. 2.

In order for the upstream wall 114a to be parallel to an aligned sidewall 102c of the packages 102, the chain 120 carrying the carrier elements 114 via the back wall 114e should be at an equal angle a to a line that is perpendicular to the conveying direction of the conveyor belt 101, as can be seen in Fig. 4. The chain 120 is further arranged along a straight path at the loading station, i.e. where the packages are transferred from the conveyor belt 101 to the transport device 103. The carrier elements 114 are hence conveyed by the chain 120 at an angle to the conveying direction of the conveyor belt 101 such that the upstream wall 114a is parallel with the aligned wall 102c of the packages 102. If the angle of the slots 114d matches the angle of the packages 102, the downstream wall 114b is parallel to the forward facing wall 102b of the package 102 (to the left in Fig. 4), after the packages 102 have been aligned by the guiding bar 105.

With the above configuration of the carrier elements 114, the packages 102 can be conveyed very close together, since only a small movement of a filled slot 114d, in the transport direction, is required for allowing a subsequent package 102 to enter the slot 114d of a downstream carrier element 114. The speed v_c of the transport device 103 should be set to match the speed v_p of the packages on the conveyor belt 101, such that a constant clearance g₂, between package wall 102b and downstream wall 114b, can be maintained during loading. In this way the package 102 is almost completely inside the slot 114d, without touching the angled walls 114a, 114b, until the upstream wall 114a contacts the aligned wall 102c of the package 102. The front fin 102a of the package has then entered the groove 114c in the carrier element 114. It is also possible to drive the packages 102 against the downstream wall 114b, such that the package follows that wall until the package is fully inside the slot 114d and the upstream wall 114a contacts the aligned package wall 102c.

The transport device 103 is given a background speed that corresponds to the calculated nominal speed, which is the required speed to catch a perfect flow of packages with the same distance d between each other. The speed of the transport device 103 is regulated around the nominal speed, by using servo technology. This gives a very smooth motion with few jerks.

It may be beneficiary to control the orientation of the front fin 102a of the package 102 such that it is vertical. In order to accomplish this, the final path of the conveyor belt 101 is angled downwards an angle β corresponding to half of the top angle of the package, see Fig. 5.

The package in Fig. 5 furthermore has one wall 102c aligned with the transport direction of the conveyor belt 101, so the package is slightly angled to the right, looking from the downstream end of the conveyor belt. Because of this, and the fact that the package is leaning downwards, the front fin is actually angled slightly to the left. If wanted, the conveyor belt 101 can hence also slightly be angled to the right, as seen from the downstream direction, i.e. the right side of the conveyor is lower than the left side of the conveyor as seen in Figs. 1 and 4, at the loading station, in order to have a front fin 102a that is more truly vertically aligned. This facilitates handling of the packages at a downstream station, where the packages are taken from the transport device 103 to e.g. a cardboard box.

In an alternative embodiment, the carrier element 114 is shaped with a slot 114d that is not symmetrical in relation to a line that is perpendicular to the back wall 114e. Instead, the slot is angled in relation to the back wall 114e such the chain 120 of the transport device 103 can be arranged at a 90 degree angle to the conveying direction of the packages. This then needs to be handled further downstream, since the packages are arranged symmetrically.

The first and second embodiments of the transport device 103, having slightly different configuration of the carrier elements 104, 114, can use the same control system for controlling the synchronization of the conveyor belt (with packages) and the transport device, can use the same sensors for detecting the passage and speed of packages, can use the guiding bar in the same way, and can have the same configuration of the conveyor belt, with regards to the angles etc.

Although the present invention has been described above with reference to specific embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the invention is limited only by the accompanying claims and, other embodiments than the specific above are equally possible within the scope of these appended claims.

In the claims, the term "comprises/comprising" does not exclude the presence of other elements or steps. Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by e.g. a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. The terms "a", "an", "first", "second" etc do not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.

Claims

1. A transport system (100) comprising a conveyor belt (101) for conveying objects (102), a transport device (103) comprising a number of carrier elements (104) for carrying an object (102) each, said transport device (103) being placed next to said conveyor belt (101), such that said object (102) can be fed from said conveyor belt (101) to said transport device (103) for transporting the object (102) along a transport path, a first sensor (106) for detecting said object on said conveyor belt (101), and a controller, configured to regulate a motion of said transport device (103) based on data from said first sensor, such that said object is timely received by one of said number of carrier elements (104).

2. The transport system according to claim 1 , further comprising a second sensor (107) for detecting a speed of said conveyor belt (101), and said controller being configured to regulate a motion of said transport device (103) based on data from said first sensor (106) and said second sensor (107).

3. The transport system according to claim 1 or 2, wherein said first sensor (106) is a photo cell.

4. The transport system according to any of the preceding claims, wherein said second sensor (107) is a rotating encoder.

5. The transport system according to any of the preceding claims, wherein a guiding bar (105) is arranged along said conveyor belt (101), such that objects (102) will be contacted by said guiding bar (105) and aligned with the direction of movement of the conveyor belt (101).

6. The transport system according to claim 5, wherein the guiding bar (105) has a guiding zone (105b), in which the guiding bar slants medially in the direction of movement in relation to the conveyor belt (101).

7. The transport system according to claim 5 or 6, wherein said guiding bar (105) is S-shaped.

8. The transport system according to claim 1, wherein the carrier elements (104, 114) are provided with angled walls (104a, 104b; 114a, 114b) matching the shape of the object (102) to be transported.

9. The transport system according to claim 8, wherein upstream walls (104a,

114a) of the carrier elements (104, 114) are aligned with the direction of movement of the conveyor belt (101) at a station where packages (102) are transferred from the conveyor belt (101) to the transport device (103).

10. The transport system according to claim 9, wherein the angled walls (104a, 104b; 114a, 114b) are arranged symmetrically in the carrier element (104, 114), in relation to a back wall (114e) of the carrier element (114).

11. The transport system according to claim 1, wherein the object (102) is a package with tetrahedral shape.