WO2012122632A1

WO2012122632A1 - Density regulation system and method thereof

Info

Publication number: WO2012122632A1
Application number: PCT/CA2012/000234
Authority: WO
Inventors: Franck Klotz
Original assignee: Sidel (Canada) Inc.
Priority date: 2011-03-11
Filing date: 2012-03-12
Publication date: 2012-09-20

Abstract

A single file combiner includes conveyor assembly conveying a plurality of items in bulk into a single file. A method of regulating a density of the items on the combiner includes detecting by a sensor at least some of the items; calculating by at least one controller in communication with the sensor a density of the at least some of the items; comparing the density to a predetermined density; controlling a speed of the at least one motor based on the comparison; and adjusting a flow rate of the plurality of items on the conveyor assembly as a result of controlling the speed of the at least one motor by the at least one controller. The density is related to a percentage of presence of the at least some of the plurality of items during one of a time interval and a distance interval.

Description

Our ref. : 266268.43

DENSITY REGULATION SYSTEM AND METHOD THEREOF

CROSS-REFERENCE

[0001] This application claims priority to United States Provisional Application Serial No. 61/451,646, filed March 11, 2011, entitled 'Density Regulation System for Regulating Density of a Flow of Articles', the entirety of which is incorporated herein by reference.

TECHNICAL FIELD

[0002] The present relates to density regulation systems and method thereof, and more specifically to density regulation systems and method of regulating a density of a flow of items on a single file combiner.

BACKGROUND

[0003] Single file combiners are used in manufacturing and/or packaging processes to convey items, such as plastic bottles or aluminum cans, from a first location to a second location. Items are received in bulk at a first end of the single file combiner at the first location and are carried towards a second end of the single file combiner to the second location. The single file combiner is further configured to align the items in one or more single files as they move from the first end of the single file combiner to the second end of the single file combiner, such that they can be delivered in this configuration from the second end of the single file combiner to the second location. When the items are disposed in a single file, the items are lined up one after the other so as to form a single row. An example of multiple single files combiner is described in US Patent No. 6,206,174.

[0004] Taking the example of a particular type of single file combiner, namely a pressure free combiner, the pressure free combiner comprises a plurality of movable surfaces (also named tracks) onto which the items are received. The movable surfaces are typically

D _MTU266268-00043/2763695.1 1 Our ref. : 266268.43

pluralities of belts. The pluralities of belts are adjacent to each other in the longitudinal direction, and each plurality includes several belts adjacent to each other in the lateral direction. The belts are actuated by motors so as to move in the longitudinal direction, ^' thereby creating the movable surfaces. Each belt is driven at a specific speed. The speeds are selected so as to form a longitudinal and transversal "speed gradient" over the pressure free combiner.

[0005] The pressure free combiner is usually provided with a guide rail which extends generally obliquely across the belts. The guide rail is positioned at a distance vertically over the tracks to enable the items conveyed on the tracks to contact the guide rail, but to prevent the guide rail from contacting the tracks. The guide rail is further slanted from the first end towards the second end of the pressure free combiner to guide the items, which are pushed against the guide rail by movement of the belts, from the slowest belt towards the fastest belt. The items are then pulled or pushed into a single file by the speed gradient and the guide rail.

[0006] The predetermined speeds of the motors associated with the belts and responsible for the speed gradients are generally determined by performing trial runs (or bench tests). Improper speed settings may result in the items being positioned in a multiple-row configuration, where they should have been positioned in a single file configuration instead. Improper speed settings may also result in the items being spaced apart from each other by a distance greater than desired, thereby decreasing the flow of items delivered at the second end of the pressure free combiner and slowing down the manufacturing and/or packaging process.

[0007] Other conditions may cause a variation in the flow of items from the first end to the second end of the pressure free combiner. For example, during the operating life of the pressure free combiner, the different mechanical parts of the pressure free combiner, such as the belts, motors driving the belts and chains operatively connecting the motors to the belts, may be subject to wear. Also, the operation of the pressure free combiner may be influenced by the quality level of lubrication provided in the pressure free combiner.

DM_MTL/266268-00043/2763695.1 2 Our ref. : 266268.43

[0008] Additionally, the pressure free combiners are usually configured according to the characteristics of a specific type of item, e.g. its shape and/or size. As a consequence, the speeds of the motors must be adjusted to function with each different type of items.

[0009] Currently, to configure the pressure free combiner for any new item to be processed or for maintenance reasons, the pressure free combiner has to be stopped and a series of manual adjustments are performed. An operator or maintenance specialist usually performs tests and adjusts each motor by trial and error. This type of adjustment could result in non precise and delayed adjustments, which in turn would result in non optimal functioning of the pressure free combiner.

[00010] There is therefore a need for a system and/or a method which would allow reconfigurations of the conveying system of a single file combiner when the flow of items is variable.

BRIEF SUMMARY

[0001 1] It is an object of the present to overcome at least some of the inconvenience mentioned above.

[00012] In a first aspect, a method of regulating a density of a plurality of items on a single file combiner is provided. The single file combiner includes an inlet adapted to receive the plurality of items in bulk, and an outlet adapted to receive the plurality of items in a single file. The single file combiner has a conveyor assembly adapted to convey the plurality of items from the inlet to the outlet. The conveyor assembly is actuated by at least one motor. The method comprises detecting by a sensor at least some of the plurality of items; calculating by at least one controller in communication with the sensor a density of the at least some of the plurality of items. The density is related to a percentage of presence of the at least some of the plurality of items during one of a time interval and a distance interval. The method comprises comparing by the at least one controller the density to a

DM TL/266268-00043/2763695.1 3 Our ref. : 266268.43

predetermined density threshold; controlling by the at least one controller a speed of the at least one motor based on the comparison; and adjusting a flow rate of the plurality of items on the conveyor assembly as a result of controlling the speed of the at least one motor by the at least one controller.

[00013] In a further aspect, the time interval is proportionally linked to the distance interval by a speed of at least a portion of the conveyor assembly.

[00014] In an additional aspect, the one of the time interval and the distance interval is predetermined.

[00015] In a further aspect, the at least one controller controls the speed of the at least one motor until the density reaches a target density.

[00016] In an additional aspect, the at least one controller controls the speed of the at least one motor by a factor proportional to a difference between the density and the target density.

[00017] In a further aspect, the target density is predetermined.

[00018] In an additional aspect, the conveyor includes a first belt and at least a second belt. The first belt is disposed at the inlet. The at least second belt is disposed toward the outlet. The at least one motor includes a first motor associated with the first belt and at least a second motor associated with the at least second belt. Controlling by the at least one controller the speed of the at least one motor includes controlling by the at least one controller the speed of the first motor.

[00019] In a further aspect, the sensor is disposed by the single file. The at least some of the plurality of items are disposed in a single file as they are detected by the sensor.

[00020] In an additional aspect, controlling by the at least one controller a speed of the at least one motor based on the comparison includes: when the density is below a

D _ TL/266268-00043/2763695.1 4 Our ref. : 266268.43

predetermined threshold, the at least one controller increasing the speed of the at least one motor.

[00021] In a further aspect, the at least one controller controls the speed of the at least one motor until the density reaches a target density, the target density being greater than the threshold density.

[00022] In an additional aspect, the at least some of the plurality of items is a plurality of excess items discarded from the single file; and the sensor senses the plurality of excess items.

[00023] In a further aspect, controlling by the at least one controller a speed of the at least one motor based on the comparison includes: when the density is above a predetermined threshold, the at least one controller decreasing the speed of the at least one motor.

[00024] In an additional aspect, the at least one controller controls the speed of the at least one motor until the density reaches a target density. The target density is lesser than the threshold density.

[00025] In a further aspect, the single file combiner is a pressure free combiner.

[00026] In yet another aspect, a density regulation system for a single file combiner is provided. The single file combiner comprises an inlet adapted to receive a plurality of items in bulk, and an outlet adapted to receive the plurality of items in a single-file. The single file combiner has a conveyor assembly conveying the plurality of items from the inlet to the outlet. The conveyor assembly is actuated by at least one motor. The density regulation system comprises a sensor detecting at least some of the plurality of items, and at least one controller in communication with the sensor and the at least one motor. The at least controller determines a density of the at least some of the plurality of items based on information sent by the sensor. The density is related to a percentage of presence of the at least some of the plurality of items during one of a time interval and a distance interval. The at least one

D _ TU266268-00043/2763695.1 5 Our ref. : 266268.43

controller compares the density to a predetermined threshold. The at least one controller controls a speed of the at least one motor based on the comparison. A flow rate of the plurality of items on the conveyor assembly is adjusted as a result of controlling the speed of the at least one motor the at least one controller.

[00027] In a further aspect, the at least one controller controls the speed of the at least one motor until the density reaches a target density.

[00028] In an additional aspect, the sensor is disposed by the single file. The at least some of the plurality of items are disposed in a single-file as they are detected by the sensor.

[00029] In a further aspect, the density is below a predetermined threshold. The at least one controller increases the speed of the at least one motor.

[00030] In an additional aspect, the at least some of the plurality of items is a plurality of excess items discarded from the single file. The sensor senses the plurality of excess items.

[00031] In a further aspect, when the density is above a predetermined threshold, the at least one controller decreasing the speed of the at least one motor.

[00032] Embodiments of the present can have at least one of the above-mentioned aspects, but do not necessarily have all of them.

[00033] Additional and/or alternative features, aspects, and advantages of embodiments of the present will become apparent from the following description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[00034] For a better understanding of the present, as well as other aspects, and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where;

DM_ MTU2S6268-00043/2763695.1 6 Our ref. : 266268.43

[00035] FIG. 1 is a top right side perspective view of a pressure free combiner;

[00036] FIG. 2 is a top plan view of the pressure combiner shown in FIG. 1 shown in connection with a machine;

[00037] FIG. 3 is the top plan view of FIG. 2 shown conveying a plurality of items;

[00038] FIG. 4 is a top plan view of a pressure combiner according to a second embodiment;

[00039] FIG. 5 A to 5C are schematics of side views of items on the pressure free combiner at different distances from each other, resulting in different densities;

[00040] FIG. 6 is a flow chart of a method of regulating a density of items for the pressure free combiner of FIG. 1 ; and

[00041] FIG. 7 is a flow chart of a method of regulating a number of excess items for the pressure free combiner of FIG. 1.

DETAILED DESCRIPTION

[00042] Referring to FIGs. 1 to 3, on a pressure free combiner 100 conveying a plurality of items 200 will be described. Although a pressure free combiner 100 is described herein, it should understood that single file combiners other than a pressure free combiner could be used. For example, a pressure combiner could be used. Also, although the pressure free combiner 100 is shown in isolation, it is contemplated that two or more pressure free combiners 100 could be used simultaneously or in partial or full alternative. For example, two pressure free combiners 100 could be facing each other and share some of their components.

[00043] Furthermore, in the embodiments described herein, the items 200 are substantially identical plastic bottles of 60 mm (2.362 inches) of diameter each. It is

D _MTL/266268-00043/2763695.1 7 Our ref. : 266268.43

contemplated however that items other than bottles could be conveyed by the pressure free combiner 100. For example, aluminums cans, or glass bottles could be used. It is also contemplated that bottles having a diameter more or less than 60 mm or bottles having a different shape than the one shown herein could be used.

[00044] The pressure free combiner 100 comprises an inlet portion 104 and an outlet portion 106 disposed opposite to the inlet portion 104 in a longitudinal direction 14 (shown in FIG. 2). Although the pressure free combiner 100 extends in the longitudinal direction 14, it is contemplated that the pressure free combiner 100 could have a different shape. For example, as shown in FIG. 4, a pressure free combiner 100' has a U-shaped configuration. An inlet 104' of the pressure free combiner 100' is disposed next to an outlet 106' of the pressure free combiner 100'. The pressure free combiner 100' also has a discontinued guide rail 150'. In another example, the pressure free combiner 100 could be S-shaped.

[00045] As best shown in FIG. 2, the inlet portion 104 of the pressure free combiner 100 receives the items 200 disposed in a multi-row configuration or bulk. By bulk, one should understand items 200 disposed side-by-side not necessarily touching each other and disposed so that they form more than one row. Throughout the pressure free combiner 102, the items can occasionally be lied down as illustrated by item 201 in FIG. 2. At the inlet 104, the items 200 form an arranged quincunx. It is contemplated that the items 200 could be disposed in bulk in a fashion other than in an arranged quincunx. For example, the items 200 could be disposed in arranged rows aligned with one another, or the items 200 could be pell-mell.

[00046] The outlet portion 106 delivers the items 200 in a single file (also sometimes referred as 'single-row') to a machine 204 (shown in FIG. 2). The machine 204 is a labeler. It is contemplated that the machine 204 could be instead a filler, a rinser, an inspector, a snifer, a full or empty bottle inspector, or any other type of machine that accepts items in a single file. It is contemplated that the machine 204 could be omitted.

D _MTL/266268-00043/2763695.1 8 Our ref. : 266268.43

[00047] The pressure free combiner 100 comprises a conveyor assembly 108conveyor assembly 108 onto which are disposed the items 200. As best seen in FIG. 2, the conveyor assembly 108conveyor assembly 108 comprises a first plurality of belts 108a, a second plurality of belts 108b disposed adjacent longitudinally to the first plurality of belts 108a, a third plurality of belts 108c disposed adjacent longitudinally to the second plurality of belts 108b, and a fourth plurality of belts 108d disposed adjacent longitudinally to the third plurality of belts 108c. Each plurality of belts 108a,b,c,d comprises several belts 110. It is contemplated that the conveyor assembly 108conveyor assembly 108 could have more or less than four pluralities of belts.

[00048] The pluralities of belts 108a,b,c,d are disposed in a stepped configuration relative to a transverse direction 12. The plurality of belts 108a,b,c,d have only a transverse portion common with their respective adjacent plurality of belts 108b,c,d. It is contemplated that the first, second, third and fourth belts 108a, 108b, 108c, 108d could be disposed transversally in line without a stepped configuration. The stepped configuration follows a curvature of a guide rail 150 (described below) and allows to reduce a number of belts 1 10 that would not be used.

[00049] Each of the plurality of belts 108a,b,c,d has a different number of belts 110. As best shown in FIG. 1, the first plurality of belts 108a has 19 belts 110. The second plurality of belts 108b has 15 belts 110. The third plurality of belts 108c has 6 belts 110. The fourth plurality of belts 108d has 1 belt 110 (hereof to sometimes referred as "fourth belt 108d" for clarity). It is contemplated that some or all of the plurality of belts 108a,b,c,d could have a same of belts 110. It is also contemplated that each of the plurality of belts 108a,b,c,d could have a number of belts 110 different than the ones recited above.

[00050] Still referring to FIG. 2, the belts 1 10 of the first, second, third and fourth plurality of belts 108a, 108b, 108c, 108d are endless belts and extend each between essentially two pulleys (not shown) in the longitudinal direction 14. For simplicity, we will consider the portion of the belt 1 10 that extends between the two pulleys to be a "length" of

DM_MTL/266268-00043/2763695.1 9 Our ref. : 266268.43

the belt 110. The pluralities of belts 108a,b,c,d each of a different length 1 14a,b,c,d in the longitudinal direction 14. The lengths 1 14a,b,c,d of the belts 108a,b,c,d are increasing longitudinally from the inlet 104 to the outlet 106, the first plurality of belts 108a being the shortest and the fourth plurality of beltsl08d being the longest. It is contemplated that the pluralities of belts 108a,b,c,d could all have a same length 114a,b,c,d or could have different lengths in a manner different from the one described above.

[00051] The first, second, third and fourth plurality of belts 108a, 108b, 108c, 108d have all a same width 112 in the transverse direction 12. It is contemplated that some or all of the pluralities of belts 108a,b,c,d could have different widths 112. The fourth belt 108d, which delivers the items 200 in a single file, is wide enough for a single item 200 to be disposed onto. The fourth belt 108d has a width 112 of 89 mm (3.5 inches). It is contemplated that the fourth belt 108d could be narrower than a single item 200. It is also contemplated that some or all of the belts 1 10 could have a width 1 12 larger or smaller than 89 mm (3.5 inches).

[00052] Each belt 110 is made of plastic. It is contemplated that the belts 1 10 could be made of a material other than plastic. For example, the belts 110 could be made of stainless steel.

[00053] A lubrication system (not shown) of water and soap is used to decrease friction between the belts 1 10 and the items 200. It is contemplated that the lubrication system could be of a type other than water and soap. For example, a dry lubrication system could be used. It is contemplated that the lubrication system could be omitted.

[00054] Each of the pluralities of belts 108a,b,c,d is actuated by a corresponding one of first, second, third and fourth motors 120a, 120b, 120c, 120d, respectively. Under the action of the motors 120a,b,c,d the position of the corresponding belts 108a,b,c,d, extending between the two pulleys form a movable surface which moves the items 200 in the longitudinal direction 14. The motors 120a,b,c,d are variable frequency drive (VFD) motors. It is contemplated that more or less than four motors 120a,b,c,d could be used. It is also

DM_MTL/266268-00043/2763695.1 10 Our ref. : 266268.43

contemplated that motors other than VFD motors could be used. For example, servo drive, vector controlled drive, or permanent magnet drive motors could be used.

[00055] Each of the motors 120a,b,c,d is connected to an associated control unit (not shown) which commands changes of speeds. The control units are in communication with a controller 130 (shown in FIG.l). The controller 130 will be described below. It is contemplates that the control units could be omitted and that the controller 130 (or a plurality of controllers) could directly command an operation of the motors 120a,b,c,d.

[00056] In order to convey the items 200 from the inlet 104 in the multi-row (or bulk) configuration to the outlet 106 in the single file, the motors 120a,b,c,d are adjusted at different speeds so as to accelerate the item 200 along the longitudinal direction 14. A first gradient of speed of the belts 110 in the longitudinal direction 14 accelerates the item 200 as they travel from the inlet 104 to the outlet 106. To do so, an operator inputs via a touch screen display 140 (shown in FIG. 1) a first motor speed to the first motor 120a, a second motor speed, higher than the first motor speed to the second motor 120b, a third motor speed higher than the second motor speed to the third motor 120c, a fourth motor speed higher than the third motor speed to the fourth motor 120d. The controller 130 relays the inputted information to the control units of each motor 120a,b,c,d. For example, the first motor speed is set to run at 10 m/s, the second motor speed is set to run at 20 m/s, the third motor speed is set to run at 30 m/s, and the fourth motor speed is set to run at 40 m/s. It is contemplated that the display 140 could not be touchscreen. For example, a keyboard could be connected to a conventional display. It is also contemplated that the display 140 could be omitted, and the speed of the motors 120a,b,c,d could be inputted by a removable device, such as a laptop. It is also contemplated that the motors 120a,b,c,d could be programmed to run at speeds other than the ones recited above. In one example, some or all of the motors 120a,b,c,d could have a same speed.

[00057] A series of pinions and clutch (not shown) associated with each motor 120a,b,c,d allows to create a second gradient of speed of the belts 1 10 in the transverse direction 12. The

DM_MTL/266268-00043/2763695.1 1 1 Our ref. : 266268.43

pinions and clutches are set up such that the belts 110 of a given plurality of belts 108a,b,c,d closer to the guide rail 150 travel faster than the belts 110 of that given plurality of belts 108a,b,c,d further away the guide rail 150. As illustrated in FIG. 2, the plurality of belts 108b actuated by the second motor 120b is set up along a transverse segment 13 to run the belt 110a the closer to the guide rail 150 faster than the belt 1 10b further away from the guide rail 1 0. It is contemplated that the gradient of speed of the belts 110 in the transverse direction 12 could be achieved in a manner different from using pinions and clutches. For example, each belt 110 could be controlled electronically.

[00058] The guide rail 150 will now be described. The guide rail 150 is disposed obliquely across the conveyor assembly 108 and has a curved shape toward the inlet 104 which transitions smoothly to a line shape toward the outlet 106. The shape of the guide rail 1 0 has been designed so that when the pluralities of belts 108a,b,c,d are actuated, the items 200 disposed on the belts 108a,b,c,d are continuously directed towards the guide rail 150. Using the transversal and longitudinal speed gradients of the belts 110, the items 200 are pushed against the guide rail 150. In turn, the bulk disposition on the first belt 108a is transformed into a single file of items 200 on the fourth belt 108d.

[00059] The guide rail 150 is spaced vertically above the conveyor assembly 108 so that it does not contact the conveyor assembly 108. The guide rail 150 is fixed while the conveyor assembly 108 moves under the action of the motors 120a,b,c,d, and the space (not shown) between the guide rail 150 and the conveyor assembly 108 allows to at least reduce friction between the guide rail 150 and the conveyor assembly 108. The space is also large enough to let a lying down item 203 (shown in FIG. 2) pass between the belts 110 and the guide rail 150. It is contemplated that the space could be so small to not accommodate the lying down item 203 between the belts 1 10 and the guide rail 150.

[00060] A chute 160 is disposed on a lateral left side of the pressure free combiner 100 and collects excess items 204. The items 200 of the third belt 108c which are in a multi-row configuration are urged onto the fourth belt 108d in a single file by the guide rail 150. Excess

DM_MTL/266268-00043/2763695.1 12 Our ref. : 266268.43

items 204 are pushed off the third plurality of belts 108c into the chute 160. The chute 160 is configured to automatically redirect the excess items 204 back onto the inlet portion 104 of the pressure free combiner 100 (not shown). It is contemplated that the excess items 204 may be collected by an operator and placed back in the inlet portion 104 of the pressure free combiner 100. It is also contemplated that the chute 160 could be disposed elsewhere on the pressure free combiner 100. For example, the chute 160 could be disposed longitudinally about the second plurality of belts 108b. It is also contemplated that the chute 160 could be omitted.

[00061] A sensor 162 (shown in FIG. 2) detects and counts the excess items 204 falling into the chute 160. The sensor 162 is positioned such it only counts the excess items 204 that are upright items. That way, only those items 200 that could not fit into the single file are counted and not the items 203 that have fall over during the conveying. It is contemplated that the sensor 162 could sense items 200 other than just the upright ones. The sensor 162 is in communication with the controller 130. A method 400 of regulating the excess items 204 will be described below.

[00062] A chute 170 is disposed on a lateral right side of the pressure free combiner 100 and collects the excess items 203 that have gone beneath the guide rail 150. It is contemplated that the chute 170 could be disposed elsewhere on the pressure free combiner 100. It is also contemplated that the chute 170 could be omitted.

[00063] A sensing assembly 180 is disposed at the fourth belt 108d near the outlet portion 106 of the pressure free combiner 100. The sensing assembly 180 is in communication with the controller 130. The sensing assembly 180 counts a number of items 200 in the single file during a predetermined time interval Atl . The information collected by the sensing assembly 180 is processed by the controller 130 to determine a density of the items 200 in the single file. The predetermined time interval Atl will be described below.

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[00064] The density expresses a rate of occupation of the items 200 when in the single file. The density expresses the percentage of presence of items 200 in the single file within a predetermined time interval Atl (also expressible as a percentage of occupation of bottles on the conveyor assembly 108 over a predetermined length). As illustrated in FIGs. 5A to 5C, the items 200 can be disposed on the fourth plurality of belts 108d at various distances from each other. In FIG. 5 A for example, the items 200 are disposed at a constant space 107a from each other representing a density of 70%. In FIG. 5B, the items are disposed at a constant space 107b from each other smaller than the space 107a, and representing a density of 85%. In FIG. 5C, the items are disposed at a variable space 107c from each other different from the space 107byet representing a same density of 85%. The predetermined time interval Δίΐ will be described below. A method 300 of regulating the density of the items 200 using the sensing assembly 180 will be described below.

[00065] As shown in FIG. 2, the sensing assembly 180 includes an optical sensor 182 positioned on one side of the fourth belt 108d and a reflector 184 positioned opposite to the one side. It is contemplated that positions of the optical sensor 182 and the reflector 184 could be different than the ones shown in FIG. 2. It is also contemplated that the sensing assembly 180 system could comprise sensors other than the optical sensor 182. For example, the sensing assembly 180 could include one or more of laser sensors, capacitive or inductive proximity sensor, sonic sensors, camera or video camera (such as a high speed high resolution camera), a light curtain, a source of radio waves, microwaves or other radiations.

[00066] The sensing assembly 180 functions as follows. In operation, a beam of light is emitted towards the reflector 184. If an item 200 is present between the optical sensor 182 and the reflector 184 when the beam of light is emitted, the beam of light will not be reflected towards the optical sensor 182. If no item 200 is present between the optical sensor 182 and the reflector 184 when the beam of light is emitted, the beam of light is reflected towards the optical sensor 182 by the reflector 184. The optical sensor 182 thereby obtains a "measurement" indicating whether or not an item 200 is present between the optical sensor

DM_MTU266268-00043/2763695.1 14 Our ref. : 266268.43

182 and the reflector 184. The measurement is then transmitted to the controller 130. The time needed by the sensing assembly 180 to perform the measurement is fixed. Each measurement takes 0.005 seconds to be performed. The fixed time the sensing assembly 180 needs to perform each measurement is depending on the sensing assembly 180 and is not controllable by the operator. The relationship between a measurement and an individual item 200 is not one-to-one. Two consecutive measurements could detect the presence of the same item 200. Since the sensing assembly 180 does not count the number of items 200 but rather the density of the items 200, the sensing system 180 takes measurements at a speed greater than the speed of the fourth plurality of belts 108d. It is contemplated however that some sensing system could be used where such sensing systems could allow a selection of the fixed time needed to perform a measurement. It is contemplated that the measurements could take less or more than 0.005 seconds to be performed. Is it possible that the relationship between the measurements and an individual item 200 in the single file could be one-to-one.

[00067] The optical sensor 182 and the reflector 184 are positioned so that the beam of light is perpendicular to the fourth plurality of belts 108d. It is contemplated however that the optical sensor 182 and the reflector 184 could be positioned so that the beam of light could be at an angle other than being perpendicular to the fourth plurality of belts 108d.

[00068] Turning now to FIG. 6, the method 300 of regulating the density of the items 200 will now be described. Although the method 300 is described in combination with the pressure free combiner 100, it is contemplated that the method 300 could be applied to a type of single file combiner other than a pressure free combiner.

[00069] The method 300 starts at step 302. From step 302, the method 300 goes to step 304.

[00070] At step 304, a counter is set to zero. From step 304, the method 300 goes to step 306.

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[00071] At step 306, the counter is added a unit. From step 306, the method 300 goes to step 308.

[00072] At step 308, the sensing assembly 180 records a presence of the items 200 in the single file onto the fourth plurality of belts 108c during a predetermined time interval Atl . The predetermined time interval Atl lasts 6 seconds. It is contemplated that the predetermined time interval Atl could last less or more than 6 seconds. Deciding elements for the choice of the length of the predetermined time interval Δίΐ will be described below.

[00073] During the predetermined time interval Atl, the sensing assembly 180 performs a predetermined number of measurements. As mentioned above, the sensing assembly 180 does not record the presence of the items 200 in a continuous manner, but rather by performing subsequent measurements where each measurement takes up a fixed time to be performed. Thus, in the predetermined time interval Atl, there is a maximum number of measurements possible, which is determined to be the predetermined number of measurements. The predetermined time interval lasting 6 seconds and each measurement taking 0.005 seconds to be performed, the predetermined number of measurements is 1200. It is contemplated however that the predetermined number of measurements could be less than the maximum number of measurements possible within the predetermined time interval Atl . It is contemplated that the sensing assembly 180 could record the presence of the items 200 in a continuous manner, such that one could not define a predetermined number of measurements during tire predetermined time interval.

[00074] The predetermined time interval Atl and the predetermined number of measurements are determined during bench tests prior to performing the method 300 and are imputed by the operator to the controller 130 via the touch screen display 140. Criteria for determining these two values include a compromise between a precision of the measurements by the sensing assembly 180 and a measurement collection time needed to obtain such precision. Regarding the precision of the measurements, in general the higher the number of measurements during the smaller time interval, the better the precision may be. However, the

DM_MTU266268-00043/2763695.1 16 Our ref. : 266268.43

number of measurements during a given time interval is constrained by the physical capacity of the sensing assembly 180. For example the physical capacity of the sensing assembly 180 is the fixed time of 0.005 seconds needed to perform a single measurement. Furthermore, a higher time interval may be preferred to a smaller time interval in order to obtain an overall higher number of measurements. But, using a high time interval has the consequence to induce a long response time for potential actions to be performed as a consequence of the information sensed by the sensing assembly 180.

[00075] To determine the predetermined number of measurements (the predetermined time interval Δίΐ being a result of the predetermined number of measurements and the time needed by the sensing assembly 180 to perform a measurement), the work sampling method is used. It is contemplated that methods other than the work sampling method could be used. For example, real measurement and calculation of density on video cameras could be used. The work sampling method is a known statistical method, usually used to measure productivity of workers. Applied to the embodiments described herein, the work sampling method enables calculation of the predetermined number of measurements required for calculating an experimental density (N in Equation 1 below), based on a desired precision rate (S in Equation 1 below, expressed in percentage) and a theoretical (or target) density (P in Equation 1 below):

[00076] Ν - ^ί^ (Equation 1).

S x P

[00077] For example, if one desires a measured density with a desired precision S of 1 % and a target density P of 90%, 4444.4 measurements would be needed, and the first predetermined number of measurements would be 44445. In order to perform 44445 measurements knowing that each measurement lasts 0.005 seconds, the first predetermined time interval will be 22 seconds.

[00078] From step 308, the method 300 goes to step 310.

DMJV1TL/266268-00043/2763695.1 17 Our ref. : 266268.43

[00079] At step 310, the sensing assembly 180 communicates the sensed information with the controller 130 and the controller 130 calculates the density of the items 200 during the predetermined time interval Atl . The sensing assembly 180 communicates in real-time with the controller 130, i.e. after each of the measurements. The controller 130 stores in a database (not shown) the information received from the sensing assembly 180 until the predetermined time interval Atl (or the predetermined number of measurements) has elapsed. It is contemplated that the sensing assembly 180 could have a storage unit to store the measurements until the predetermined time interval Atl has elapsed, and only then could send the information to the controller 130.

[00080] To calculate the density, the controller 130 is program as follows. If for example, for a predetermined number of measurements of 1200 the presence (i.e. the predetermined time interval Atl is 6s) of the items 200 has been recorded 1000 times, the density is of 83.33 %. Once the density is calculated, the controller 130 stores the information in the database.

[00081] From step 310, the method 300 goes to step 312.

[00082] At step 312, the count is compared with an end value. The end value prior to the method 300 is inputted by the operator via the display 140. The end value corresponds to the number of times the controller 130 will calculate a density before averaging it at step 314. The end value is set up to be 50, which corresponds to measurements made during 5 minutes. Deciding elements for the choice of the end value are similar to the ones described above with respect to the predetermined time interval Atl . It is contemplated that the end value could be less or more than 50. For example, the end value could be 1 , and steps 304, 306 and 312 could be omitted.

[00083] If, at step 312, the count is not the end value, the method 300 goes back to step 306. If, however, at step 312, the count is the end value, the method 300 goes to step 314.

DM_MTL/266268-00043/2763695.1 18 Our ref. : 266268.43

[00084] At step 314, the controller 130 averages the past 50 densities calculated at step 310 and stores the average density in the database. From step 314, the method 300 goes to step 316.

[00085] At step 316, the controller 130 compares the average density calculated at step 314 with a predetermined threshold. The predetermined threshold is determined during bench tests and inputted by the operator using the touchscreen display 140. The predetermined threshold corresponds to a value of the density below which the pressure free combiner 100 is deemed to not operate at a desired level of efficiency. For example, a density of 60% could indicate that the items 200 are too spaced with respect to each other, and that additional items 200 need to be conveyed by the pressure free combiner 100 so as to reduce a distance between the items. In another example, a density of 60% could indicate a large gap between two items 200 resulting for example from lying items 203, the rest of the items 200 being spaced at a much smaller distance. The predetermined threshold is 85%. It is contemplated that the predetermined threshold could be a density of more or less than 85%.

[00086] If the density calculated at step 316 is above the predetermined threshold, the method 300 goes back to step 318 and stops.

[00087] If the density calculated at step 316 is on or below the predetermined threshold, the method 300 goes to step 320.

[00088] At step 320, the controller 130 controls the motor 120a so as to increase the number of items 200 conveyed. In order to do so, the controller 130 increases the speed of the motor 120a by an amount directly proportional to a difference between the density calculated at step 304 and a target density. The proportionality between the speed of the motor 120a and the difference between the density calculated at step 304 and a target density depends on a plurality of factors. These factors include the arrangement of the items 200 onto the first plurality of belts 108a (e.g. quincunx as opposed to arranged rows) and the lubrication. Other factors may be considered. It is contemplated that none or some of the

DM_ TL7266268-00043/2763695.1 19 Our ref. : 266268.43

above factors may be considered. It is contemplated that the motor 120a could be controlled differently than described above. For example, the controller 130 could increase the speed of the motor 120a by a predetermined amount related yet not proportional to the difference between the calculated density and the target density. In another example, the controller 130 could increase the speed of the motor 120a by a predetermined amount independently of the difference between the calculated density and the target density. It is contemplated that the motor 120a could be controlled proportionally to the difference of densities only for some speed. For example, a speed limit could be predetermined or calculated in real time such that above a certain speed, the motor 120a may not be increased.

[00089] The target density is determined prior to the method 300 taking into account various factors. The target density is inputted by the operator using the touchscreen display 140. Factors to determine the target density include non exhaustively the type of items 200 conveyed and/or the types of operations which may be performed on the items 200 delivered from the pressure free combiner 100 (e.g. labeling and packaging). The target density is calculated by the controller 130 based on the threshold density. The target density is predetermined to be a density 3% above the threshold density (i.e. 88%). It is also contemplated that the target density could be the threshold density. It is contemplated that the target density could be calculated by a way other than applying 3% to the threshold density.

[00090] From step 320, the method 300 goes to step 322. Given that the step 302 is continuously performed, the method 300 is constantly sensing the items 200 in the single file, calculating the density and adjusting the speed of the motor 120a accordingly, thereby providing a feedback control on the motor 120a and adjusting a flow rate of the plurality of items 200 on the pressure free combiner 100.

[00091] Although the above method 300 has been described with the controller 130 controlling solely the motor 120a, it is contemplated that the method 300 could control either one of the motors 120a,b,c,d alone or in combinations. It is also contemplated that the controller 130 could control the speed of only one or some of the belts 1 10 of the first

DM_MTL/266268-00043/2763695.1 20 Our ref. : 266268.43

plurality of belts 108a,b,c,d associated with the motors 120a,b,c,d controlled by the method 300.

[00092] Turning now to FIG. 7, the method 400 of controlling the excess items 204 will now be described. Although the method 400 is described in combination with the pressure free combiner 100, it is contemplated that the method 400 could be applied to a type of single file combiner other than a pressure free combiner. Also, although the method 400 is described in association with the method 300, it is contemplated that the methods 300 and 400 could be performed independently from each other.

[00093] The method 400 starts at step 402. From step 402, the method 400 goes to step 404.

[00094] At step 404, a counter is set to zero. From step 404, the method 400 goes to step 406.

[00095] At step 406, the counter is added a unit. From step 406, the method 400 goes to step 408.

[00096] At step 408, the sensor 162 detects the excess items 204 falling to the chute 160 during a predetermined time interval Δΐ2. As mentioned above, the sensor 162 counts only the excess items 204 that are upright items so that only those items 200 that could not fit into the single file are counted and not the items 203 that have fall over during the conveying. The predetermined time interval Δί2 lasts 6 seconds. It is contemplated that the predetermined time interval Δί2 could last less or more than 6 seconds. Deciding elements for the choice of the length of the predetermined time interval Δΐ2 are similar to the ones described above with respect to the predetermined time interval Atl and will not be repeated. Although the predetermined time interval At2 is of a same length than the predetermined time interval Δίΐ for synchronization purposes, it is contemplated that they could be different. From step 408, the method 400 goes to step 410.

DM_ TL 266268-00043/2763695.1 21 Our ref. : 266268.43

[00097] At step 410, the sensor 160 communicates the information regarding the excess items 204 detected as falling into the chute 160 to the controller 130. The controller 130 calculates a number of excess items 204 during the predetermined time interval Δί2. It is contemplated that given that the controller 130 also has information about the items 200 that did reached the fourth belt 108d and did fit into the single file, the controller 130 can express the number of excess items 204 per predetermined time interval Δί2 into a percentage of efficiency of the pressure free combiner 100. It is also contemplated that knowing a size of the items 200 at a point where they are sensed by the sensor 162, the controller could calculate a density. It is also contemplated that the controller 130 could compute a value representative of the amount of excess items 204 discarded from the single file other than by calculating the number of excess items 204 per time interval Δί2. From step 410, the method 400 goes to step 412.

[00098] At step 412, the count is compared with an end value. The end value is inputted by the operator via the display 140. The end value corresponds to the number of times the controller 130 will calculate the number of excess items 204 per predetermined time interval Δί2 before averaging it at step 414. The end value is set up to be 5 (i.e. measurements are being made during 30s, and a number of excess items 204 is calculated every 6 s). Deciding elements for the choice of the end value are similar to the ones described above with respect to the end value associated with predetermined time interval Atl and will not be repeated. It is contemplated that the end value could be less or more than 5. For example, the end value could be 1, and steps 404, 406 and 412 could be omitted.

[00099] If, at step 412, the count is not the end value, the method 400 goes back to step 406. If, however, at step 412, the count is the end value, the method 400 goes to step 414.

[000100] At step 414, the controller 130 averages the past 5 times where the number of items 206 per time interval Δί2 has been calculated at step 410. From step 414, the method 400 goes to step 416.

DM_MTU2662S8-00043/2763695.1 22 Our ref. : 266268.43

[000101] At step 416, the controller 130 compares the numbers calculated at step 414 with a predetermined threshold. The predetermined threshold is a number of excess items 204 per time interval At2 above which the pressure free combiner 100 is deemed to be operating inefficiently. If a too great number of items 200 is discarded as excess items 204 and pushed into the chute 160, the pressure free combiner 100 is deemed to be inefficient as it conveys too many items 200 too fast towards the single file on the fourth plurality of belts 108d. As mentioned above, these numbers could be expressed differently, for example as percentages of efficiency or densities, and the comparison could be made with respect to predetermined threshold of percentages of efficiency or densities. The predetermined threshold is determined by the operator. The predetermined threshold is determined taking into account the fact that the method 300 is performed concomitantly to the method 400, so that the controller 130 does not receives conflicting instructions from the methods 300 and 400. For example, the method 400 is priority over the method 300. It is contemplated however that the method 300 could instead be priority with respect to the method 400, or that a decision criterion other than the ones described above could be used. The predetermined threshold is inputted by the operator via the display 140 before the start of the method 400. The predetermined threshold is 6 items per 30 seconds (the predetermined time interval Δΐ2 being 6 seconds). It is also contemplated that the predetermined threshold could not be determined taking into account the fact that the method 300. This could be the case when, for example, the method 300 not performed. From step 414, the method 400 goes to step 416.

[000102] If, at step 416, the average number of excess items 204 detected during the predetermined time interval At2 is less than the predetermined excess items threshold, the method 400 goes to step 418 and stops.

[000103] If, however, at step 416 the average number of excess items 204 detected during the predetermined time interval M2 is more than the predetermined excess items threshold, the method 400 goes to step 420.

DM_MTL/266268-00043/2763695.1 23 Our ref. : 266268.43

[000104] At step 420, the controller 130 controls the control unit of the motor 120a to decrease the speed of the motor 120a in order to decrease the flow of the items 200. The controller 130 decreases the speed of the motor 120a by an amount directly proportional to a difference between the number of excess items 204 detected and the predetermined excess items threshold. It is contemplated that the motor 120a could be controlled differently than described above. The controller 130 could decrease the speed of the motor 120a by a predetermined amount independently of the difference between the number of excess items 204 detected and the predetermined excess items threshold. For example, a fixed amount of speed decrease could be applied by the controller 130 to the motor 120a no matter what the difference between the number of excess items 204 detected and the predetermined excess items threshold is. For step 406, the method 400 goes back to step 402, thereby providing a constant feedback loop.

[000105] From step 420, the method 400 goes to step 422. Given that the step 402 is continuously performed, the method 400 is constantly sensing the excess items 204 falling into the chute 160, calculating their number per time interval Δΐ2 and adjusting the speed of the motor 120a accordingly, thereby providing a feedback control on the motor 120a and adjusting the flow rate of the plurality of items 200 on the pressure free combiner 100.

[000106] Although the above method 400 has been described with the controller 130 controlling solely the motor 120a, it is contemplated that the method 400 could control either one of the motors 120a,b,c,d alone or in combinations. It is also contemplated that the controller 130 could control the speed of only one or some of the belts 110 of the first plurality of belts 108a associated with the motor 120a. It is contemplated that the method 300 and 400 could control different motors 120a,b,c,d from one another.

[000107] It will be appreciated that the pressure free combiner 100 may have other configurations, depending on various factors such as the type of items conveyed, the space available and, if the pressure free combiner is used in series with other machines and/or conveyors, the location of the other machines and/or conveyors.

DM_MTL/266268-00043/2763695.1 24 Our ref. : 266268.43

[000108] Modifications and improvements to the above-described embodiments of the present may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the present is therefore intended to be limited solely by the scope of the appended claims.

D _ TL7266268-00043/2763695.1 25

Claims

Our ref. : 266268.43 What is claimed is:

1. A method of regulating a density of a plurality of items on a single file combiner, the single file combiner including an inlet adapted to receive the plurality of items in bulk, and an outlet adapted to receive the plurality of items in a single file, the single file combiner having a conveyor assembly adapted to convey the plurality of items from the inlet to the outlet, the conveyor assembly being actuated by at least one motor, the method comprising: detecting by a sensor at least some of the plurality of items;

calculating by at least one controller in communication with the sensor a density of the at least some of the plurality of items, the density being related to a percentage of presence of the at least some of the plurality of items during one of a time interval and a distance interval;

comparing by the at least one controller the density to a predetermined density threshold;

controlling by the at least one controller a speed of the at least one motor based on the comparison; and

adjusting a flow rate of the plurality of items on the conveyor assembly as a result of controlling the speed of the at least one motor by the at least one controller.

2. The method of claim 1, wherein the time interval is proportionally linked to the distance interval by a speed of at least a portion of the conveyor assembly.

3. The method of any one of claims 1 and 2, wherein the one of the time interval and the distance interval is predetermined.

4. The method of any one of claims 1 to 3, wherein the at least one controller controls the speed of the at least one motor until the density reaches a target density.

D _MTL/266268-00043/2763695.1 26 Our ref. : 266268.43

5. The method of claim 4, wherein the at least one controller controls the speed of the at least one motor by a factor proportional to a difference between the density and the target density.

6. The method of any one of claims 4 and 5, wherein the target density is predetermined.

7. The method of any one of claims 1 to 6, wherein the conveyor includes a first belt and at least a second belt;

the first belt is disposed at the inlet,

the at least second belt is disposed toward the outlet;

the at least one motor includes a first motor associated with the first belt and at least a second motor associated with the at least second belt; and

controlling by the at least one controller the speed of the at least one motor includes controlling by the at least one controller the speed of the first motor.

8. The method of any one of claims 1 to 7, wherein the sensor is disposed by the single file; and

the at least some of the plurality of items are disposed in a single file as they are detected by the sensor.

9. The method of claim 8, wherein controlling by the at least one controller a speed of the at least one motor based on the comparison includes:

when the density is below a predetermined threshold, the at least one controller increasing the speed of the at least one motor.

10. The method of any one of claim 9, wherein the at least one controller controls the speed of the at least one motor until the density reaches a target density, the target density being greater than the threshold density.

D _MTL/266268-00043/2763695.1 27 Our ref. : 266268.43

11. The method of any one of claims 1 to 8, wherein the at least some of the plurality of items is a plurality of excess items discarded from the single file; and

the sensor senses the plurality of excess items.

12. The method of claim 11 , wherein controlling by the at least one controller a speed of the at least one motor based on the comparison includes:

when the density is above a predetermined threshold, the at least one controller decreasing the speed of the at least one motor.

13. The method of claim 12, wherein the at least one controller controls the speed of the at least one motor until the density reaches a target density, the target density being lesser than the threshold density.

14. The density regulation system of any one of claims 1 to 13, wherein the single file combiner is a pressure free combiner.

15. A density regulation system for a single file combiner, the single file combiner comprising an inlet adapted to receive a plurality of items in bulk, and an outlet adapted to receive the plurality of items in a single-file, the single file combiner having a conveyor assembly conveying the plurality of items from the inlet to the outlet, the conveyor assembly being actuated by at least one motor, the density regulation system comprising:

a sensor detecting at least some of the plurality of items; and

at least one controller in communication with the sensor and the at least one motor, the at least controller determining a density of the at least some of the plurality of items based on information sent by the sensor, the density being related to a percentage of presence of the at least some of the plurality of items during one of a time interval and a distance interval, the at least one controller comparing the density to a predetermined threshold, the at least one controller controlling a speed of the at least one motor based on the comparison, a

DM_ TL/266268-00043/2763695.1 28 Our ref. : 266268.43

flow rate of the plurality of items on the conveyor assembly being adjusted as a result of controlling the speed of the at least one motor the at least one controller.

16. The method of claim 12, wherein the at least one controller controls the speed of the at least one motor until the density reaches a target density.

17. The method of any one of claims 15 and 16, wherein the sensor is disposed by the single file; and

the at least some of the plurality of items are disposed in a single-file as they are detected by the sensor.

18. The method of claim 17, wherein when the density is below a predetermined threshold, the at least one controller increasing the speed of the at least one motor.

19. The method of any one of claims 15 and 16, wherein the at least some of the plurality of items is a plurality of excess items discarded from the single file; and

the sensor senses the plurality of excess items.

20. The method of claim 19, wherein when the density is above a predetermined threshold, the at least one controller decreasing the speed of the at least one motor.

D _MTL/266268-00043/2763695.1 29