Conveyor system and method

Abstract

A method can include defining a path of movement for articles with a plurality of drive rollers mounted on one or more framing systems. The method can also include conveying a first article of the plurality of the articles along the path of movement with the drive rollers. The method can also include determining a length, along the path of movement, of the first article. The method can also include continuously monitoring a position of the first article along the path of movement during the conveying. The method can also include directly driving each of the drive rollers in rotation with a respective motor of a plurality of motors. The method can also include controlling, during the conveying, a group of motors of the plurality of motors that are respectively driving drive rollers that are directly under the first article to rotate uniformly at a first speed of rotation.

Description

CONVEYOR SYSTEM AND METHODBACKGROUND1. Field

[0001] The present disclosure relates to systems for conveying and transporting articles, such as having roller driving components, and control devices therefore, such as classified in Cooperative Patent Classification class B65.2. Description of Related Prior Art

[0002] U.S. Pat. No. 7063206 discloses an accumulating conveyor system and method of accumulating articles includes providing an accumulation assembly that is adapted to accumulating a plurality of articles into a slug of articles. Slugs of articles are discharged to a transport line which transports the slugs and accumulates the slugs as required. The accumulation assembly is made up of a slug forming section which forms slug portions and discharges slug portions into slugs. The accumulation assembly accumulates articles in zones and reduces gaps between articles in sequence from upstream gaps to downstream gaps.

[0003] U.S. Pat. No. 7542823 discloses a zone controlled conveyor system and a zone controller for use therein that aims to provide a zone controlled conveyor system including a plurality of zones for control. A zone controlled conveyor system, while conveyance of any article from a zone to a downstream zone is forbidden, (a) starts operation of a driving roller in the zone at a first conveying speed slower than a prescribed standard conveying speed upon detection of a presence of an article from an immediately upstream zone of the zone, (b) operates the driving roller at a second conveying speed slower than the first conveying speed after arrival of the article at a predetermined position in the zone, and (c) halts operation of the driving roller upon detection of a presence of the article in the zone. Thereby, the system enables to stop articles at a target position accurately.

[0004] U.S. Pat. No. 7631747 discloses a conveyor induct system, a method and apparatus for controlling gaps between articles traveling on a conveyor system includes providing a plurality of tandem conveying surfaces defining a series of sequentially arranged conveying surface interfaces. At least one of the conveying surfaces associated with each of said conveying surface interfaces is an adjustable-speed conveying surface. At least one article sensor is provided adjacent at least one of the conveying surface interfaces. The article sensor provides information on positions of the articles. The speeds of the tandem conveying surfaces are controlled in a manner that establishes controlled gaps between articles, by identifying a controllable gap that can be adjusted between articles at aparticular conveying surface interface and adjusting the controllable gap at the particular conveying surface interface. The control adjusts the controllable gap by adjusting the speed of the adjustable speed conveying surface associated with the particular conveying surface interface using a feedback controller. Gaps between articles are sequentially adjusted at the series of sequentially arranged conveying surface interfaces.

[0005] U.S. Pat. No. 8028817 discloses a conveyor and conveyor controller. The conveyor, which has an area in its conveyor line and for adjusting intervals between articles, includes (1) a plurality of zones constituting the area and each having at least one driving motor and an article sensor, (2) structure for measuring either an interval between adjacent articles in the conveying direction or a difference of time points when adjacent articles in the conveying direction pass the sensor, and (3) a motor controller for each of the zones and for varying a rotational speed of the driving motor. When the measuring structure measures either the interval or the difference upon reception of signals from the sensor, the motor controller either accelerates or slows down the rotational speed of the driving motor in a zone where the article is placed.

[0006] U.S. Pat. No. 8695786 discloses singulated release for zoned conveyor systems. The disclosure describes zoned conveyor systems that provide singulated package release control based on a defined displacement distance using motor revolution data of a downstream conveyor zone.

[0007] U.S. Pat. No. 8757363 discloses conveyor controllers. Various methods, apparatuses, and program products that are used to control at least a portion of a conveyor, determine information about an article conveyed by the conveyor, or otherwise operate a conveyor are provided. One method includes detecting whether a second conveyor controller is connected to the first conveyor controller and, in response to detecting that there is a second conveyor controller connected to the first conveyor controller, identifying whether the second conveyor controller is connected to a predetermined network interface of the first conveyor controller. The method further includes configuring the first conveyor controller to rotate a motorized roller in a first predetermined direction if a second conveyor controller is connected to the predetermined network interface and configuring the first conveyor controller to rotate the motorized roller in a second predetermined direction if a second conveyor controller is not connected to the predetermined network interface.

[0008] U.S. Pat. No. 9321598 discloses a conveyor and weight sensing method using the conveyor with an object of providing a conveyor which estimates weight of a transport object while it is carried without using devices such as a load cell which directly measures weight. The conveyor has a plurality of zones forming a series of carriage ways. An approach-run zone and a weightmeasurement zone are arranged adjacently in the conveying direction and are provided with differentdrive motors. The drive motor of the approach-run zone and the drive motor of the weightmeasurement zone are controlled with respectively different predetermined rotation speeds as their target rotation speeds. A rotation speed sensing means obtains the change of rotation speed of the drive motor in the weight-measurement zone when a transport object is conveyed into the weightmeasurement zone from the approach-run zone, and a weight sensing means then calculates the weight of the transport object based on the change of the rotation speed.

[0009] U.S. Pub. No. 20200299068A1 discloses a method for monitoring the state of a conveyor system, and a control unit, a motorized roller, and a conveyor system for carrying out the method. The method for state monitoring in a conveyor system, and also to a control unit, to a motorized roller, to a conveyor zone, to a conveyor section and to a conveyor system for carrying out this method. The method comprises checking for the presence of a reference operating state, determining a current of the motorized roller if the reference operating state is present, and comparing the determined current of the motorized roller with a reference value for the reference operating state.

[0010] U.S. Pub. No. 20220009722A1 discloses a Conveyor Arrangement with Integrated Sensor Function Unit. The conveyor arrangement for conveying a conveyed material, comprising a motor-driven conveyor roller, comprising a roller body mounted so as to be able to rotate about a roller axis, a drive unit arranged inside the roller body, coupled mechanically to the roller body and an axle element and designed to generate a torque between the axle element and the roller body, a sensor function unit arranged inside the roller body and designed to sense a conveyed material to be conveyed by the motor-driven conveyor roller, and a control unit that is connected to the sensor function unit in order to transmit signals, wherein the control unit is designed to receive a sensor signal from the sensor function unit and to transmit a control signal to the drive unit depending on the sensor signal, wherein the control signal contains data for driving the motor-driven conveyor roller, in a conveyor mode, with a characteristic profile that is predefined by the control signal.

[0011] Figure l is a schematic representation of a conveying system 38 according to the prior art. The conveying system 38 includes a framing system 40 and rollers 1 - 36 mounted on the framing system 40 for rotation relative thereto. The rollers 1 - 36 are arranged in a plurality of zones, including zones A - D. Rollers 1 - 9 define zone A, rollers 10 - 18 define zone B, rollers 19 - 27 define zone C, and rollers 28 - 36 define zone D. Rollers 5, 14, 23, and 32 are drive rollers and are thus driven directly by a respective or dedicated motor (not shown). The rollers 5, 14, 23, and 32 can contain within themselves a motor, gearbox, and electronic motor controllers. Each of the exemplary rollers 5, 14, 23, and 32 can be characterized as the prime mover for the rollers in its zone. It is notedthat there are conveyor systems in the art wherein the motors are not in the rollers but are located under the rollers with belted connections. This is not illustrated in Figure 1.

[0012] Rollers 1 - 4 and 6 - 9 are indirectly driven in rotation by roller 5 through the use of belts. The belts are visually represented similarly in Figure 1. An exemplary belt is referenced by number 42. Similarly, rollers 10 - 13 and 15 — 18 are indirectly driven in rotation by the roller 14 through the use of belts. Rollers 19 - 22 and 24 - 27 are indirectly driven in rotation by the roller 23 through the use of belts. Rollers 28 - 31 and 33 - 36 are indirectly driven in rotation by the roller 32 through the use of belts.

[0013] The conveying system 38 also includes sensors that can detect an article moving along the conveyor system 38. The sensors are represented similarly in Figure 1 and one is referenced at 44. Each zone is monitored and controlled by a zone controller, such as zone A controller 46. Each zone controller can be similarly configured and operate similarly. The zone A controller 46 can receive signals from the sensor 44 and control the motor of the drive roller 5 in response to the signals received from the sensor 44. The conveying system 38 also includes multi -zone controllers, such as multi-zone controller 48. Each multi-zone controller can be similarly configured and operate similarly. Each multi-zone controller can control the operations of the zone controllers within its multi-zone. The conveying system 38 also includes a system controller 50 configured to control all of the multi-zone controllers.

[0014] The background description provided herein is for the purpose of generally presenting background context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.SUMMARY

[0015] This section provides a simplified summary in order to provide a basic understanding of some aspects described herein. This summary is not an extensive overview and is not intended to identify “key” or “critical” elements of the present disclosure or to delineate the scope of the various aspects described herein. The purpose of this portion of the document is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0016] A method can include defining a path of movement for a plurality of articles with a plurality of drive rollers mounted on one or more framing systems. The method can also include conveying a first article of the plurality of the articles along the path of movement with the pluralityof drive rollers. The method can also include determining a length, along the path of movement, of the first article of the plurality of the articles. The method can also include continuously monitoring a position of the first article of the plurality of the articles along the path of movement during said conveying. The method can also include directly driving each of the plurality of drive rollers in rotation with a respective one motor of a plurality of motors. The method can also include controlling, during said conveying, a group of motors of the plurality of motors that are respectively driving a group of drive rollers that are directly under the first article to rotate uniformly at a first speed of rotation.

[0017] According to other features, the method can also include rotating at least one drive roller of the plurality of drive rollers that is outside of the group of drive rollers directly under the first article with a motor of the plurality of motors that is outside of the group of motors, at a second speed different than the first speed.

[0018] In other features, the method can also include conveying a second article of the plurality of the articles along the path of movement with the plurality of drive rollers. The method can also include determining a length, along the path of movement, of the second article of the plurality of the articles. The method can also include continuously monitoring a position of the second article of the plurality of the articles along the path of movement during said conveying. The method can also include controlling a second group of motors of the plurality of motors that are respectively driving a second group of drive rollers that are directly under the second article to rotate uniformly at the second speed of rotation.

[0019] According to additional features, the controlling can include continuously changing the drive rollers of the plurality of drive rollers that are in the group of rollers during the conveying as the first article moves along the path of movement. The continuously changing can further include adding a first drive roller of the plurality of drive rollers to the group of drive rollers during the conveying and after the group of drive rollers is initially defined. The adding can occur when the first article comes to be directly above the first drive roller. The adding can be further defined as adding the first drive roller to the group in response to a change in an operating characteristic of a first motor of the plurality of motors that is directly driving the first drive roller.

[0020] According to other features, the continuously changing can include removing a second drive roller from the group of drive rollers during the conveying and after the group of drive rollers is initially defined. The removing can occur when the first article comes out of contact with the second drive roller. The removing can be further defined as removing the second drive roller fromthe group of drive rollers in response to a change in an operating characteristic of a second motor of the plurality of motors that is directly driving the second drive roller.

[0021] In other features, the continuously changing can be further defined as continuously changing drive rollers of the plurality of drive rollers that are in the group of drive rollers during the conveying as the first article moves along the path of movement in real-time.

[0022] According to additional features, the defining of the path of movement can be further defined defining the path of movement for the plurality of articles only with the plurality of drive rollers mounted on the one or more framing systems. Alternatively, the defining can be further defined as defining the path of movement for the plurality of articles with the plurality of drive rollers and with a plurality of freely rotating gravity roller. The plurality of drive rollers and the plurality of freely-rotating gravity rollers can be altematingly arranged along the path of movement and mounted on the one or more framing systems.

[0023] According to other features, the continuously monitoring can include detecting a leading edge of the first article. The continuously monitoring can also include collecting a plurality of values each respectively corresponding to an operating parameter of one of the plurality of motors. The plurality of values can include at least one operating parameter of all of the plurality of motors. The continuously monitoring can also include determining the position of the first article in response to the detecting and the collecting.

[0024] In other features, the determining of the position can further comprise ascertaining that the first article has slipped across at least one drive roller of the group of drive rollers in real-time in response to the plurality of values collected from the group of motors during the collecting. The determining of the position can further comprise ascertaining the position of the first article based on at least one operating parameter of one of the plurality of motors that is not in the group of motors.

[0025] According to additional features, the directly driving can be further defined as directly driving each of the plurality of drive rollers with the respective one motor of the plurality of motors and without a gear box positioned between any of the plurality of drive rollers and the respective one motor.

[0026] According to other features, the method can also include communicating, from each of the plurality of motors to a region controller, a plurality of operating characteristics of the respective motor over a wireless or wired network. The method can also include assigning a respective address on the wireless or wired network to each of the plurality of motors that is based on a relative position of the respective motor along the path of movement.

[0027] A conveyor system can include one or more framing systems, a plurality of drive rollers, a plurality of motors, at least one sensor, and a region controller. The plurality of drive rollers can define a path of movement for a plurality of articles and can be mounted on the one or more framing systems. The plurality of motors can each directly drive one of the plurality of the drive rollers in rotation. The plurality of motors and the plurality of drive rollers can be configured to convey each of the plurality of the articles along the path of movement. The at least one sensor can be mounted on the one or more framing systems along the path of movement and can be configured to detect proximity of at least one of the plurality of articles within a predetermined distance. The region controller can be configured to determine a length, along the path of movement, of each of the plurality of the articles moving along the path of movement. The region controller can also be configured to continuously monitor respective positions of each of the plurality of the articles moving along the path of movement. The region controller can also be configured to control all of the plurality of motors such that a group of drive rollers that are directly under a first article rotate uniformly at a first speed of rotation and such that the group of drive rollers is continuously changing as the first article moves along the path of movement.

[0028] In other features, the region controller can be configured to communicate through a wired network with each of the plurality of motors. Alternatively, the region controller can be configured to communicate with the plurality of motors wirelessly. The region controller can also be configured to continuously receive operating data from each of the plurality of motors. The region controller can also be configured to transmit operating commands to each of the plurality of motors based at least in part on the operating data received.

[0029] According to additional features, the path of movement may only by defined by the plurality of drive rollers, each directly driven by one of the plurality of motors, without a gear box positioned between any of the plurality of drive rollers and a single motor of the plurality of motors. Each of the plurality of rollers can include an anti-skid coating.BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The detailed description set forth below references the following drawings:

[0031] Figure l is a schematic representation of a conveyor system according to the prior art;

[0032] Figure 2 is a schematic representation of a conveyor system according to a first exemplary embodiment of the present disclosure; and

[0033] Figure 3 is a schematic representation of a conveyor system according to a second exemplary embodiment of the present disclosure.DETAILED DESCRIPTION

[0034] A plurality of different embodiments of the present disclosure is shown in the Figures of the application. Similar features are shown in the various embodiments of the present disclosure. Similar features across different embodiments have been numbered with a common reference numeral and have been differentiated by an alphabetic suffix. Also, to enhance consistency, the structures in any particular drawing share the same alphabetic suffix even if a particular feature is shown in less than all embodiments. Similar features are structured similarly, operate similarly, and / or have the same function unless otherwise indicated by the drawings or this specification. Furthermore, particular features of one embodiment can replace corresponding features in another embodiment or can supplement other embodiments unless otherwise indicated by the drawings or this specification.

[0035] The present disclosure, as demonstrated by the exemplary embodiment described below, can provide an enhanced conveyor system and method. In the embodiments disclosed herein, the controlling of motorized drive rollers (“MDRs”) is dynamic in that a number of MDRs that are controlled jointly (controlled to rotate at a similar speed) is determined based on the size of a present or immediate article that is being moved and the location of the article along the path of movement. The MDRs that are jointly controlled define a zone and this zone can change dynamically, in real time, as the article moves along the conveyor system. MDRs can be added to the zone and dropped from the zone as the article moves. This dynamic zone control enhances the efficiency of moving articles along the conveyor system. In contrast, the inventors have perceived that the prior art discloses fixedly defined “zones” of rollers, some of which may be MDRs and some of which may be indirectly driven rollers. Any particular roller in the prior art, directly or indirectly driven, is thus part of an unchanging zone or group of rollers.

[0036] The present disclosure provides a system in which a zone can be dynamically defined and thus changeable in real-time as an article moves along a conveying path. As a result, a conveyor system according to the present disclosure can maximize a pack ratio. The conveyor system pack ratio, as that term is used herein, is the length along the conveyor system that is occupied by articles over the total length along the conveyor system. In a facility that handles a large range of package or article sizes, the zone length (or number of rollers coupled together along the path of movement) is selected to accommodate the largest-sized package in a single zone. Because of this, the conveyor pack ratio in the prior art can be quite low, perhaps fifty percent in some cases, meaning that only half of the conveyor surface contains a package at any one time. Embodiments of the present disclosure can increase the conveyor pack ratio to as high as ninety -five percent.

[0037] Further, when a fixed-zone conveyor system senses an article that is being conveyed it inherently has uncertainty regarding where, within the current zone, the article is. The fixed-zone conveyor system may be able to sense the time that an article enters a particular zone, but if slippage occurs within that zone then the system cannot predict when it will leave the zone and enter the next zone. This problem is significant when it is desired to maintain or achieve relatively little space between articles.

[0038] Referring now to Figure 2, an exemplary conveyor system 52 includes one or more framing systems, such as exemplary framing system 54. The exemplary frame system 54 is depicted schematically, but can include beams, bars, fasteners, or any other structures to define a framework for supporting other structures. The exemplary frame system 54 can be modular and expandable.

[0039] The exemplary conveyor system 52 also includes a plurality of drive rollers defining a path of movement for a plurality of articles and mounted on the one or more exemplary framing systems. Exemplary drive rollers are represented similarly in Figure 2 and are configured similarly. Several of the exemplary drive rollers are referenced in Figure 2, at 56, 58, 60, 62, 64. The exemplary drive rollers 56, 58, 60, 62, 64 are mounted on the exemplary framing system 54 for rotation. The exemplary path is referenced at 66 in Figure 2. Each of the exemplary drive rollers 56, 58, 60, 62, 64 is a “drive” roller in that it is driven directly in rotation by a motor (which will be more fully explained below). It is noted that the path 66 can be a subpart of a larger path of movement; a plurality of iterations of the exemplary conveyor system 52 can be arranged in series or the exemplary conveyor system 52 can be arranged in a series with other, differently configured conveying systems.

[0040] The exemplary conveyor system 52 also includes a plurality of motors each directly driving one of the plurality of the drive rollers in rotation. The plurality of motors and the plurality of drive rollers are configured to convey each of the plurality of the articles along the path 66 of movement. Exemplary motors are represented similarly in Figure 2 and are configured similarly. Several of the drive motors are referenced in Figure 2, at 68, 70, 72, 74, 76. The exemplary motors 68, 70, 72, 74, 76 are respectively mounted within one of the exemplary rollers 56, 58, 60, 62, 64. A pair consisting of a drive roller and a motor (such as drive roller 56 and motor 68) can be referred to as a motorized drive roller (“MDR”) assembly. The exemplary motors 68, 70, 72, 74, 76 are brushless, direct current (“BLDC”) electric motors. In various embodiments of the present disclosure, the exemplary motors can be BLDC motors, DC motors, induction motors, or any other form of motor technology that is consistent with operation of the exemplary conveyor system 52.

[0041] The exemplary conveyor system 52 also includes at least one sensor mounted on the exemplary framing system 54 along the path 66 of movement. An exemplary sensor is referenced inFigure 2 at 78. The exemplary sensor 78 is configured to detect proximity of an article on the path 66. The exemplary sensor 78 is configured to emit a detection signal when an article is sensed and emits the detection signal as long as the article is proximate. The exemplary sensor 78 has a known range of detection so that, when the presence of an article is sensed, it can be determined that the article is a predetermined distance from the exemplary sensor 78. Various sensing methodologies can be applied in embodiments of the present disclosure. The exemplary sensor 78 can be a photoeye sensor, but other physical properties can be the basis of detection. While only one sensor is shown in Figure 2, embodiments of the present disclosure can include sensors located periodically along the length of the path, every ten or twenty feet for example.

[0042] The exemplary conveyor system 52 also includes a region controller 80. An exemplary controller that can be utilized, after appropriate programming to accomplished the activity set forth herein, is a Beagle Bone Black PN#102110420 by BeagleBoard by Seed Studio. The exemplary region controller 80 can communicate with the sensor 78 and with each of the motors associated with the drive rollers. The exemplary region controller 80 can receive the detection signal from the sensor 78. The exemplary region controller 80 transmits control signals to control the operation of each motor, such as controlling the speed of rotation for each motor and thus controlling the speed of rotation of each drive roller. The exemplary region controller 80 can also receive operational data from each motor. The exemplary region controller 80 can collect a plurality of values from the motors. Each of the plurality values can respectively correspond to an operating parameter of one of the plurality of motors. The plurality of values can include at least one operating parameter of all of the plurality of motors.

[0043] Figure 2 displays a bus-like line element referenced at 82 to represent communication between the exemplary region controller 80 and the sensor 78 and between the exemplary region controller 80 and the exemplary motors, including motors 68, 70, 72, 74, 76. While it is certainly possible for each motor and physical presence sensor to directly connect to the region controller, it does present an issue of a significant amount of cable to exist in the framing system of the conveyor system 52 and adds significant cost. In a preferred embodiment, the motors and physical presence sensors such as sensor 78 can make use of a network connection to reduce the cost and installation problems that direct connection methods present. The exemplary region controller 80 is configured to communicate with each of the plurality of motors and the sensor 78 over a wired network, but could be configured to communicate wirelessly. In such a system, the region controller 80 can serve as the network master and the network provides the path through which all data and commands are transferred between the region controller and the motors and sensors. The exemplary regioncontroller 80 is configured to continuously receive operating data from each of the plurality of motors and to transmit operating commands to each of the plurality of motors based at least in part on the operating data that is received. Each of the motors can be assigned a respective address on the network that is based on the relative position of the respective motor along the path 66 of movement. In this context, a motor is defined to include the electromagnetics such as a stator and a rotor and also include the control electronics such as communication electronics, commutation electronics for the BLDC, and speed / current control loops. While BLDC technology is the preferred embodiment, DC motors and induction motors could also be used as could any other motor technology. One aspect of this network communication is an association between network address and physical relative position of each node in the network. In other words, the region controller 80 can be configured to have knowledge of the relative physical position of each addressed roller and physical package presence sensor associated with its network address. It should be noted that each region controller is enabled to communicate via a second network that contains a system controller 88 that is configured to communicate high level conveyance requirements such as maximum conveyance speed and acceleration, accumulation advance commands such as advance forward one package at a time when triggered, and package grouping transport such as convey a group of two or more packages as a unit. Furthermore, this second network can be further enabled to allow one region controller to “hand-off’ a package to another region controller. This hand-off could include a simple binary trigger indicating that package position control is handed from one region to the next or this could further include package information. By establishing communications at the roller level, the region controller 80 can take the place of numerous, traditional zone controllers, from thirty to one hundred traditional zone controllers replaced by a single region controller as set forth herein.

[0044] The exemplary region controller 80 is configured to recognize a leading edge of an article in response to input from the sensor 78. In particular, the exemplary region controller 80 is configured to recognize the leading edge of the article in response to receiving the detection signal. Further, the exemplary region controller 80 is configured to determine a length of the article, along the path 66 of movement, based on the time period during which the detection signal is received as well as the speed of rotation of the drive rollers proximate to the sensor 78. For example, the exemplary region controller 80 receives data from a motor 84 indicative of the speed of rotation of the motor 84. The exemplary region controller 80 can include a memory in which is stored dimensional data of the drive rollers so that, for example, the speed of rotation of the motor 84 can be converted to a rotational speed of a roller 86. Further, the rotational speed of the roller 86 can be converted to a rectilinear velocity, along the path 66, of an article being moved by the roller 86. Thus,the length of the article is the time of the detection signal multiplied by the velocity of the article along the path 66.

[0045] The exemplary region controller 80 is further configured to continuously monitor the respective positions of each of the plurality of the articles that is moving along the path 66 of movement. The determination of the position of each of the plurality of the articles moving along the path 66 of movement is based on, or in response to, the initial detecting of each article and also the continuous collecting of operating data from all of the motors. The exemplary conveyor system 52 can utilize operational data received by the exemplary region controller 80 from the motors to determine the position of each of the plurality of the articles moving along the path 66 of movement after the initial detection occurs. This data is utilized to confirm or correct the determination of the position of each of the plurality of the articles as movement continues along the path 66 since it is possible that slippage can occur during movement along the path 66 after an article has passed the sensor 78.

[0046] Various forms of operational data that can be communicated to the region controller 80 can be utilized by the region controller 80 to confirm or correct the position of an article along the path 66. These forms include, by way of example and not limitation, motor current levels, proportional-integral-derivative (“PID”) loop error, motor speed in open loop control, or input current. However, it should be understood that the physical presence sensors such as sensor 78 could be placed much closer together and complete the function without the motor feedback. Alternatively, the physical presence sensors could be removed altogether and the motor feedback could complete the monitoring / determination function by itself. In still other embodiments, the package presence data can be supplied by a visual imaging system based on camera technology. In the case wherein the system makes use of motor parameter monitoring from one or more motors, the accuracy of the data can be increased by increasing the friction between the drive roller and the packages being conveyed. In one embodiment, this can be accomplished with an anti-skid coating, such as a urethane coating, being applied to the drive roller.

[0047] The exemplary region controller 80 is configured to ascertain whether that the first article has slipped across at least one drive roller in real-time in response to the plurality of values collected from the group of motors during the collecting. If the exemplary region controller 80 determines that the article has slipped, the exemplary region controller 80 is configured to correct or revise the determined position of the article along the path 66. A position of a package or article is sensed first when a package appears in the system along path 66. When it is sensed again, after the first time it is sensed, a new position is understood. In addition, the package position is advanced inthe software based on the conveyance speed. When the expected position, based on the conveyance speed, does not match the new package position then slippage has occurred. When slippage is detected the system can simply track the slippage and continue to convey the package at the previous speed. The system can also react to the slippage detection by increasing the speed of the package conveyance to make up for the slippage. This slippage reaction can be accomplished open-loop by simply increasing the speed for a specific duration. Slippage reaction can also be accomplished in a closed-loop manner wherein the system uses changes in conveyance speed as well as subsequent package position measurements as feedback to correct the position.

[0048] The exemplary region controller 80 is configured to control all of the plurality of motors such that a group of drive rollers that are directly under a first article rotate uniformly at a first speed of rotation. “Directly under” refers to drive rollers on which the article rests. With reference to Figure 2, the drive rollers 58, 60 and 62 are directly under the article 90. Further, MDRs defined by drive roller 58 - motor 70, drive roller 60 - motor 72, and drive roller 62 - motor 74 are moving the article 90 along the path 66. It is noted that the first speed of rotation can be selected as desired but is typically maximized. The size of the group of drive rollers can be variable as needed based on the length of the article along the path 66. The exemplary region controller 80 is directing the motors 70, 72, 74 to rotate the drive rollers 58, 60, 62 as a group, to rotate uniformly, to rotate together at the same speed. Rollers outside the group can rotate differently or not rotate.

[0049] The group of drive rollers is continuously changing as the article moves along the path 66. The changes of the group can be made in real-time. For example, the exemplary region controller 80 can add the drive roller 64 to the group during the conveying and after the group of drive rollers is initially defined as including drive rollers 58, 60, 62. The exemplary region controller 80 can add the drive roller 64 to the group rotating uniformly when the article 90 comes to be directly above the drive roller 64. The exemplary region controller 80 can determine when to add the drive roller 64 (and determine when the article 90 is on the driver roller 64) in response to a change in an operating characteristic of the motor 76.

[0050] Similarly, the exemplary region controller 80 can remove the drive roller 58 from the group during the conveying and after the group of drive rollers is initially defined as including drive rollers 58, 60, 62. The exemplary region controller 80 can remove the drive roller 58 from the group rotating uniformly when the article 90 comes out of contact with the drive roller 58. The exemplary region controller 80 can determine when to remove the drive roller 58 (and determine when the article 90 is no longer on the driver roller 58) in response to a change in an operating characteristic of the motor 70.

[0051] It is noted that the drive rollers that are not supporting / moving the article 90 can be rotated at a second speed different than the first speed. For example, driver rollers 92, 94, 96, 98 can be rotated as the second speed to convey the article 100 along the path 66. Movement of articles at different speeds can be utilized to form slugs along the path 66. A “slug” is a series of articles arranged as close together as desired.

[0052] Each of the exemplary drive rollers is directly driven by one of the plurality of motors, without a gear box positioned between any of the plurality of drive rollers and the corresponding, single motor of the plurality of motors. Relatively significant amounts of energy are required to convey package flows through one motor and thus necessitates a gearbox to better make use of the traditional BLDC or DC motor design speed ranges. Moreover, the presence of a gearbox requires fairly significant rotational damping to prevent failures due to shock loading from frequent start / stop behaviors with heavy, applied loads and yet there are still failures of gearboxes in the products. Thus, omitting gearbox(es) reduces cost and rotational damping means as well.

[0053] In the embodiment of the present disclosure shown in Figure 2, the path 66 of movement is defined only with a plurality of drive rollers. Referring now to Figure 3, an exemplary conveyor system 52a includes an exemplary framing system 54a, a plurality of drive rollers, and a plurality of freely rotating gravity rollers. The plurality of drive rollers and the plurality of freely rotating gravity rollers define a path 66a of movement for a plurality of articles and are mounted on the exemplary framing system 54a for rotation.

[0054] Exemplary drive rollers are represented similarly in Figure 3 and are configured similarly. Several of the exemplary drive rollers are referenced in Figure 3 at 56a, 60a, 64a. Exemplary freely rotating gravity rollers are represented similarly in Figure 3 and are configured similarly. Examples of the exemplary freely rotating gravity rollers are referenced in Figure 3 at 58a and 62a. The exemplary rollers 58a and 62a are freely rotatable and not driven in rotation, such as by a motor or a belt. The plurality of drive rollers and the plurality of freely-rotating gravity rollers are altematingly arranged along the path 66a of movement, as shown in Figure 3.

[0055] Another feature of the first embodiment shown in Figure 2 that may not be readily apparent is an ability to maintain high levels of functionality in the presence of a failed motor. Without a gearbox and without power applied, the rolling resistance (otherwise known as cogging torque or back-drive torque) of the roller is very low compared to a traditional MDR. Therefore, when the motor fails it effectively becomes a gravity roller and except for very small packages; the functionality of dynamic zone control of the first embodiment remains and rough package handling is avoided. If it were the case that package sizes were so small that there were less than three rollers under thepackage at any one time, there could be some minor loss of functionality but MDR conveyors are not typically used unless three rollers can be used for each package. In an extreme case of two failed motors in a row or at least powering the same package, the benefit is smaller in that the package would need to have a length of at least four rollers. In the context of the second embodiment shown in Figure 3, the risk is higher because it would mean that three rollers in a row were effectively gravity rollers. In this case, the uninterrupted function with a failed motor would only apply to packages have at least six rollers under them.

[0056] What has been described above includes examples of the subject innovation. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the disclosed subject matter, but many further combinations and permutations of the subject innovation are possible. The use of any and all examples, or exemplary language (e g., “such as”) provided herein is intended merely to be illustrative and does not pose a limitation on the scope of any innovation disclosed herein unless otherwise claimed. The word “exemplary” is used to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word “exemplary” is intended to present concepts in a concrete fashion. Further, any statements set forth within the Detailed Description of this document and addressing a prior art device(s) are the observations of the inventors and such statements themselves are not prior art or admissions as to what is prior art.

[0057] As used herein, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Unless indicated otherwise by context, the term “or” is to be understood as an inclusive “or.” Terms such as “first”, “second”, “third”, etc. when used to describe multiple devices or elements, are so used only to convey the relative actions, positioning and / or functions of the separate devices, and do not necessitate either a specific order for such devices or elements, or any specific quantity or ranking of such devices or elements. Use of the terms “about” or “approximately” are intended to cover values that are above and / or below a stated value or range, or within manufacturing tolerances, as would be understood by one having ordinary skill in the art in the respective context. In some instances, this may encompass values in a range of approx. + / -10%; in other instances there may be encompassed values in a range of approx. + / -5%; in yet other instances values in a range of approx. + / -2% may be encompassed; and in yet further instances, this may encompass values in a range of approx. + / -1%.

[0058] It will be understood that the terms “comprises” and / or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / orcomponents, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof, unless indicated herein or otherwise clearly contradicted by context. Recitations of a value range herein, unless indicated otherwise, serves as a shorthand for referring individually to each separate value falling within the stated range, including the endpoints of the range, each separate value within the range, and all intermediate ranges subsumed by the overall range, with each incorporated into the specification as if individually recited herein. Unless indicated otherwise, or clearly contradicted by context, methods described herein can be performed with the individual steps executed in any suitable order, including: the precise order disclosed, without any intermediate steps or with one or more further steps interposed between the disclosed steps; with the disclosed steps performed in an order other than the exact order disclosed; with one or more steps performed simultaneously; and with one or more disclosed steps omitted, unless expressly contradicted by the text herein or context.

[0059] While the present disclosure has been described with reference to one or more exemplary embodiments, it is to be understood that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure is not limited to a particular embodiment disclosed herein as the best mode contemplated for carrying out this present disclosure, but that the present disclosure will be viewed as covering any embodiment falling within the scope of the appended claims. Various aspects or features described herein may be implemented as a method, apparatus, or article of manufacture using standard programming and / or engineering techniques.

[0060] Also, the right to claim for patent coverage a particular sub-feature, a sub-component, or a sub-element of any disclosed embodiment, singularly or in one or more sub-combinations with any other sub-feature(s), sub-component(s), or sub-element(s), is hereby unconditionally reserved by the Applicant. Also, particular sub-feature(s), sub-component(s), and sub -el emen t(s) of one embodiment that is disclosed herein can replace particular sub-features, sub-components, and subelements of another embodiment disclosed herein or can supplement and be added to another embodiment unless expressly indicated otherwise by the drawings or this specification. The inventors also assert that any of the claims set forth after this detailed description can be combined with any other claim or claims regardless of whether or not there is a direct line of dependency, unless there is an express indication in this text or the drawings unambiguously indicating that such a combination is not possible. The order of the claims and the lines of dependency are irrelevant to the various waysthat the features, elements, sub-elements, components, sub-components, etc. ofthe present disclosure can be combined and thus claimed. Further, the use of the word “can” in this document is not an assertion that the subject preceding the word “can” is unimportant or unnecessary or “not critical” relative to anything else in this document. The word “can” is used herein in a positive and affirming sense and no other motive should be presumed. More than one patentable “invention” may be disclosed in the present disclosure and it is noted that an “invention” is defined by the content of a patent claim and not by the content of descriptive text or drawings.

Claims

CLAIMSWhat is claimed is:

1. A method comprising: defining a path of movement for a plurality of articles with a plurality of drive rollers mounted on one or more framing systems; conveying a first article of the plurality of the articles along the path of movement with the plurality of drive rollers; determining a length, along the path of movement, of the first article of the plurality of the articles; continuously monitoring a position of the first article of the plurality of the articles along the path of movement during said conveying; directly driving each of the plurality of drive rollers in rotation with a respective one motor of a plurality of motors; and controlling, during said conveying, a group of motors of the plurality of motors that are respectively driving a group of drive rollers that are directly under the first article to rotate uniformly at a first speed of rotation.

2. The method of claim 1 further comprising: rotating at least one drive roller of the plurality of drive rollers that is outside of the group of drive rollers directly under the first article with a motor of the plurality of motors that is outside of the group of motors, at a second speed different than the first speed.

3. The method of claim 2 further comprising: conveying a second article of the plurality of the articles along the path of movement with the plurality of drive rollers; determining a length, along the path of movement, of the second article of the plurality of the articles; continuously monitoring a position of the second article of the plurality of the articles along the path of movement during said conveying; and controlling a second group of motors of the plurality of motors that are respectively driving a second group of drive rollers that are directly under the second article to rotate uniformly at the second speed of rotation.

4. The method of claim 1 wherein said controlling further comprises: continuously changing the drive rollers of the plurality of drive rollers that are in the group of drive rollers during said conveying as the first article moves along the path of movement.

5. The method of claim 4 wherein said continuously changing further comprises: adding a first drive roller of the plurality of drive rollers to the group of drive rollers during said conveying and after the group of drive rollers is initially defined, said adding occurring when the first article comes to be directly above the first drive roller.

6. The method of claim 5 wherein said adding is further defined as: adding the first drive roller to the group of drive rollers in response to a change in an operating characteristic of a first motor of the plurality of motors that is directly driving the first drive roller.

7. The method of claim 4 wherein said continuously changing further comprises: removing a second drive roller from the group of drive rollers during said conveying and after the group of drive rollers is initially defined, said removing occurring when the first article comes out of contact with the second drive roller.

8. The method of claim 7 wherein said removing is further defined as: removing the second drive roller from the group of drive rollers in response to a change in an operating characteristic of a second motor of the plurality of motors that is directly driving the second drive roller.

9. The method of claim 4 wherein said continuously changing is further defined as: continuously changing drive rollers of the plurality of drive rollers that are in the group of drive rollers during said conveying as the first article moves along the path of movement in realtime.

10. The method of claim 1 wherein said defining is further defined as: defining the path of movement for the plurality of articles only with the plurality of drive rollers mounted on the one or more framing systems.

11. The method of claim 1 wherein said defining is further defined as: defining the path of movement for the plurality of articles with the plurality of drive rollers and with a plurality of freely rotating gravity rollers, the plurality of drive rollers and the plurality of freely rotating gravity rollers altematingly arranged along the path of movement and mounted on the one or more framing systems.

12. The method of claim 1 wherein said continuously monitoring further comprises: detecting a leading edge of the first article; collecting a plurality of values each respectively corresponding to an operating parameter of one of the plurality of motors and the plurality of values including at least one operating parameter of all of the plurality of motors; and determining the position of the first article in response to said detecting and said collecting.

13. The method of claim 12 wherein said determining the position further comprises: ascertaining that the first article has slipped across at least one driver roller of the group of drive rollers in real-time in response to the plurality of values collected from the group of motors during said collecting.

14. The method of claim 12 wherein said determining the position further comprises: ascertaining the position of the first article based on at least one operating parameter of one of the plurality of motors that is not in the group of motors.

15. The method of claim 1 wherein said directly driving further comprises: directly driving each of the plurality of drive rollers with the respective one motor of the plurality of motors and without a gear box positioned between any of the plurality of drive rollers and the respective one motor.

16. The method of claim 1 further comprising: communicating, from each of the plurality of motors to a region controller, a plurality of operating characteristics of the respective motor over a network; and assigning a respective address on the network to each of the plurality of motors that is based on a relative position of the respective motor along the path of movement.

17. A conveyor system comprising: one or more framing systems; a plurality of drive rollers defining a path of movement for a plurality of articles and mounted on said one or more framing systems; a plurality of motors each directly driving one of said plurality of said drive rollers in rotation, said plurality of motors and said plurality of drive rollers configured to convey each of the plurality of the articles along the path of movement; at least one sensor mounted on said one or more framing systems along said path of movement and configured to detect proximity of at least one of the plurality of articles within a predetermined distance; and a region controller configured to complete at least one of: determine a length, along the path of movement, of each of the plurality of the articles moving along said path movement, continuously monitor respective positions of each of the plurality of the articles moving along said path of movement, and control all of said plurality of motors such that a group of drive rollers that are directly under a first article rotate uniformly at a first speed of rotation and such that thegroup of drive rollers is continuously changing as the first article moves along the path of movement.

18. The conveyor system of claim 17 wherein said region controller is configured to communicate directly with each of said plurality of motors over a network, to continuously receive operating data from each of said plurality of motors, and to transmit operating commands to each of the plurality of motors based at least in part on the operating data received.

19. The conveyor system of claim 17 wherein the path of movement is only defined by the plurality of drive rollers, each directly driven by one of the plurality of motors, without a gear box positioned between any of the plurality of drive rollers and a single motor of the plurality of motors.

20. The conveyor system of claim 17 wherein one or more of the plurality of rollers includes an anti-skid coating.

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