CONVEYOR SYSTEM COMPRISING AN ALIGNER FOR ALIGNING ITEMS

Abstract

A conveyor system for luggage or parcel items comprises an item conveyor for conveying the items and an aligner for aligning the items, the aligner comprising alignment means, such as tilted or slanted belts capable of changing an initial orientation of an item to a subsequent orientation of the item while the item is being conveyed along a general conveying direction of the aligner. A control system is provided for controlling the first and second conveyor elements which are arranged alongside each other and capable of simultaneously engaging an item engaging surface of the item, and individually controllable by the control system to convey at individual speeds to effect rotation of the item around an upright axis.

Claims

1. A conveyor system for luggage or parcel items, the conveyor system comprising an item conveyor for conveying the items and an aligner for aligning the items, the item conveyor being arranged to convey the items onto the aligner, wherein the aligner comprises alignment means capable of changing an initial orientation of an item to a subsequent orientation of the item while the item is being conveyed along a general conveying direction of the aligner, the alignment means comprising at least a first conveyor element and a second conveyor element and a control system for controlling the first and second conveyor elements, wherein the first conveyor element and the second conveyor element are: arranged alongside each other; capable of simultaneously engaging an item engaging surface with the item; and individually controllable by the control system to convey at individual speeds.

2. A conveyor system according to claim 1, wherein the conveyor system comprises first detection means capable of detecting the initial orientation of the item and/or second detection means capable of detecting the subsequent orientation of the item.

3. A conveyor system according to claim 2, wherein the first detection means and/or the second detection means comprise at least one laser emitter arranged to illuminate a laser pattern on at least one of the conveyor elements of the aligner and the items engaged by the at least one conveyor element, and at least one camera for capturing said laser pattern, and wherein the control system is configured to perform image analysis of the laser pattern captured by the at least one camera in order to detect the initial and/or subsequent orientation of the item.

4. A conveyor system according to claim 3, wherein the at least one laser emitter is configured to emit a laser line or a laser plane, the laser line or plane extending transversely to the general conveying direction of the aligner.

5. A conveyor system according to claim 3, wherein the camera is arranged such that a first line intersecting a focal center of a lens of the camera and a center of the laser pattern formed by the laser on the conveying element forms an acute angle with the laser line or laser plane.

6. A conveyor system according to claim 1, wherein the control system is configured to compare the initial orientation with a first set of predetermined orientations, and/or compare the subsequent orientation with a second set of predetermined orientations, and to control the first and second conveyor elements according to a first predefined control scheme if the initial orientation matches the first set of predetermined orientations and/or according to a second predefined control scheme if the subsequent orientation matches the second set of predetermined orientations.

7. A conveyor system according to claim 1, wherein the item engaging surfaces of the first and second conveyor elements are tilted towards each other to form a V-shape when seen in cross section.

8. A conveyor system according to claim 1, wherein the aligner comprises a housing with an open inlet end and an open outlet end, the housing forming at least part of a tunnel enclosing at least part of the first and second conveyor elements and arranged to limit the amount of light entering the tunnel and/or escaping the tunnel.

9. A conveyor system according to claim 1, wherein the conveyor system further comprises a centering device arranged to transversely displace items on the item conveyor, and wherein the centering device comprises: sensors for sensing an item on the item conveyor; and at least two pusher elements for engaging an item on the conveyor, the pusher elements being arranged on opposing sides of the item conveyor, and the pusher elements being drivable at least in a direction transverse a conveying direction defined by the item conveyor.

10. A conveyor system according to claim 9, wherein an item engaging surface of the item conveyor defines a first coefficient of friction, and item engaging surfaces of the pusher elements define a second coefficient of friction, and wherein the first coefficient of friction is larger than the second coefficient of friction.

11. A conveyor system according to claim 9, wherein the pusher elements comprise vertically arranged drivable conveyor belts for engaging the item on the item conveyor.

12. A conveyor system according to claim 9, wherein the centering device comprises third detection means for detected a force exerted on each of the pusher elements.

13. A conveyor system according to claim 12, wherein the transverse movement of each of the pusher elements are driven by an individual electric motor, and wherein the third detection means comprises a motor load sensor for each motor.

14. A method of conveying luggage or parcel items by use of a conveyor system, the conveyor system comprising an item conveyor for conveying the items and an aligner for aligning the items, the aligner comprising at least a first conveyor element and a second conveyor element and a control system for controlling the first and second conveyor elements, the method comprising the steps of: the item conveyor conveying an item in an initial orientation onto the aligner; engaging an item engaging surface of each of the first and second alignment elements with the item; and the control system individually controlling the speed of first and second conveyor elements to enable change of the initial orientation to a subsequent orientation.

15. A method according to claim 14, wherein the conveyor system comprises a centering device, the centering device comprising a sensor, two pusher elements arranged on opposing sides of the item conveyor, and wherein the method comprises the steps of: the sensor sensing an item on the item conveyor; the pusher elements being driven in a direction transverse a conveying direction of the item conveyor towards the centerline of the item conveyor; and the at least two pusher elements engaging the item to push it towards the centerline of the item conveyor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Embodiments of the invention will now be further described with reference to the drawings, wherein:

[0049] FIGS. 1-4 illustrate an embodiment of a conveyor system according to the invention;

[0050] FIGS. 5 and 6 illustrate the embodiment of FIGS. 1-4 including its control system; and

[0051] FIGS. 7-12 illustrate an embodiment of a conveyor system comprising a centering device according to the invention.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

[0052] The conveyor system 100 shown in the drawings comprises an item conveyor 104, by which items 102, such as parcel or luggage items 102 are conveyed to an aligner 106 for changing an orientation of the items 102 relative to a general conveying direction 108 of the item conveyor 104 and/or of the aligner 106. The aligner 106 comprises first and second conveyor elements 110, 112 in the form of tilted or slanted conveyor elements arranged alongside each other to form a V-shape when seen in cross-section.

[0053] The conveyor system 100 further comprises a first laser emitter 116 arranged at a distance from, and preferably above, the item conveyor 104, and second laser emitters 118, 122 arranged at a distance from, and preferably above, the aligner 106, notably near a downstream end section thereof. The first and second laser emitters 116, 118, 122 are arranged to illuminate laser patterns onto the item conveyor 104 and the conveyor elements 110, 112 of the aligner 106, respectively. First and second cameras 114, 120 arranged offset from the first and second laser emitters 116, 118, 122 are provided for capturing laser patterns reflected by the items 102, item conveyor 104, and the first and second conveyor elements 110, 112 of the aligner 106. A housing 124 forming at least a part of a tunnel is provided for shielding off and/or otherwise protecting the item conveyor 104 and the aligner 106, notably with a view to excluding portions of surrounding light to enhance optical light contrasts of laser light reflected by the item 102, the item conveyor 104 and/or the first and second conveyor elements 110, 112. Operation of the conveyor elements 110, 112 is controlled by control system 126.

[0054] In operation, the orientation and optionally further the size of an incoming item 102 is detected by the first camera 114 on the basis of light emitted by the first laser 116 and reflected by an upper surface of the item conveyor 104 and an upper surface of the item 102. The weight of the item may optionally further be acquired by means of a weighing unit (not shown). On the basis of the detected image, the control system 126 defines an operating scheme for the tilted conveyor elements 110, 112 of the aligner 106. More specifically, the conveyor elements 110, 112 are individually controllable by the control system 126 at individual speeds, so that the item's orientation relative to the conveyor elements 110, 112 can be altered when both of the conveyor elements 110, 112 simultaneously engage a portion of a bottom surface of the item 102. For example, the initial item orientation shown in FIG. 1 may be changed into the subsequent item orientation shown in FIG. 2 by operating the first conveyor element 110 at a higher speed than the second conveyor element 112, while the item 102 rests on the conveyor elements 110, 112, with one portion of its bottom surface resting on the first conveyor element 110 and another portion of its bottom surface resting on the second conveyor element 112.

[0055] FIG. 5 illustrates an embodiment of the control system, in which a central processing unit (CPU) 1 is provided for receiving input from the first and/or camera 114, 116 and optionally also from control elements (not shown) controlling the item conveyor 104 and/or the first and second conveyor elements 110, 112. On the basis of such inputs, the initial orientation and optionally also size and/or weight of the item 102 may be determined or estimated. A sub-PLC (programmable logic controller) 2 determines a control scheme for operation of the first and second conveyor elements 110, 112 for changing the orientation of the item 102 from initial orientation shown in FIG. 1 into the subsequent orientation shown in FIG. 2. CPU 1 and sub-PLC 2 communicate with a main PLC 3, which in turn communicates with a further control element 4 provided, e.g., for communication of sorting or other item-related data to further control elements of the control system 126 or external control units.

[0056] In the control system 126 shown in FIG. 6, the first camera 114 and optional belt motor control elements generally denoted B communicate (as indicated by arrow 1) to the CPU A. Once the CPU A has calculated a control scheme for the first and second conveyor elements 110, 112 of the aligner 106 to effect (as indicated by arrow 2) a change of orientation of the item 102 as described above, the second cameras 118, 122, forming part of a camera/laser setup generally denoted D, communicate (as indicated by arrow 3) data indicative of an orientation of the item 102 at C to the CPU A. As indicated by arrow 4, CPU A communicates data to further control element E provided, e.g., for communication of sorting or other item-related data to further control elements of the control system 126 or external control units.

[0057] FIG. 7 illustrates a centering device 200 according to an embodiment of the invention. The centering device 200 is arranged just upstream of the aligner 106 to transversely displace an item 102 on the item conveyor 104 before the item 102 is conveyed onto the first and second conveyor elements 110, 112 of the aligner 106. The item 102 is displaced towards a centerline 128 (marked in FIGS. 1, 2 and 4) defined between the first and second conveyor elements 110, 112. The centering device 200 comprises sensors 202 in the form of photo sensors for sensing an item 102 on the item conveyor 104. As an item 102 is sensed by the sensors 202, pusher elements 204 are activated and displaced towards the centerline of the item conveyor 104 coinciding with the centerline 128 between the first and second conveyor elements 110, 112.

[0058] In the embodiment illustrated in FIG. 7, the pusher elements 204 each comprises a pusher plate 208 for engaging items 102 on the item conveyor 104. Item engaging surfaces 210 of the pusher plates 208 define a second coefficient of friction smaller than a first coefficient of friction of an item engaging surface of the item conveyor 104. The relatively low coefficient of friction on the item engaging surfaces 210 of the pusher plates 208 decreases the likelihood of the pusher plates 208 decreasing the conveying speed of the item 102 on the item conveyor 104. The pusher plates 208 are coupled to pivot arms 212, which in turn are coupled to individual electric motors 214 via shafts 216. Accordingly, the torque applied by the electric motors 214 is transferred to the pivot arms 212 effectuating transverse movement, as well movement along the item conveyor 104, of the pusher plates 208 as illustrated in FIG. 8. Third detection means of the centering device 200 in the form of motor load sensors enables measurement of the force exerted on the pusher plates 208. Accordingly, the pusher plates 208 are stopped and retracted when a threshold force is reached and the item 102 has approached the centerline 128 of the aligner 106.

[0059] The functionality of the centering device 200 according to an embodiment of the invention is further illustrated in FIGS. 9-12. In FIG. 9 the sensors 202 in the form of photo sensors sense an item 102 on the item conveyor 104. This activates the electric motors 214 causing movement of the pusher elements 204 towards the item 102 as illustrated in FIG. 10. In FIG. 11 both pusher plates 208 are engaged with the centered item 102 and the threshold force is reached. In FIG. 12 the pusher elements 204 are retracting while the item 102 is conveyed onwards and onto the first and second conveyor elements 110, 112 of the aligner 106.